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Vlad Yasevich60c778b2008-01-11 09:57:09 -05001/* SCTP kernel implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 * Copyright (c) 2002 Nokia Corp.
7 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -05008 * This is part of the SCTP Linux Kernel Implementation.
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 *
10 * These are the state functions for the state machine.
11 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -050012 * This SCTP implementation is free software;
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -050018 * This SCTP implementation is distributed in the hope that it
Linus Torvalds1da177e2005-04-16 15:20:36 -070019 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
Jeff Kirsher4b2f13a2013-12-06 06:28:48 -080025 * along with GNU CC; see the file COPYING. If not, see
26 * <http://www.gnu.org/licenses/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 *
28 * Please send any bug reports or fixes you make to the
29 * email address(es):
Daniel Borkmann91705c62013-07-23 14:51:47 +020030 * lksctp developers <linux-sctp@vger.kernel.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 * Written or modified by:
33 * La Monte H.P. Yarroll <piggy@acm.org>
34 * Karl Knutson <karl@athena.chicago.il.us>
35 * Mathew Kotowsky <kotowsky@sctp.org>
36 * Sridhar Samudrala <samudrala@us.ibm.com>
37 * Jon Grimm <jgrimm@us.ibm.com>
38 * Hui Huang <hui.huang@nokia.com>
39 * Dajiang Zhang <dajiang.zhang@nokia.com>
40 * Daisy Chang <daisyc@us.ibm.com>
41 * Ardelle Fan <ardelle.fan@intel.com>
42 * Ryan Layer <rmlayer@us.ibm.com>
43 * Kevin Gao <kevin.gao@intel.com>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044 */
45
Joe Perches145ce502010-08-24 13:21:08 +000046#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
47
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <linux/types.h>
49#include <linux/kernel.h>
50#include <linux/ip.h>
51#include <linux/ipv6.h>
52#include <linux/net.h>
53#include <linux/inet.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090054#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070055#include <net/sock.h>
56#include <net/inet_ecn.h>
57#include <linux/skbuff.h>
58#include <net/sctp/sctp.h>
59#include <net/sctp/sm.h>
60#include <net/sctp/structs.h>
61
Eric W. Biederman24cb81a2012-08-07 07:28:09 +000062static struct sctp_packet *sctp_abort_pkt_new(struct net *net,
63 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 const struct sctp_association *asoc,
65 struct sctp_chunk *chunk,
66 const void *payload,
67 size_t paylen);
68static int sctp_eat_data(const struct sctp_association *asoc,
69 struct sctp_chunk *chunk,
70 sctp_cmd_seq_t *commands);
Eric W. Biederman2ce95502012-08-06 08:43:06 +000071static struct sctp_packet *sctp_ootb_pkt_new(struct net *net,
72 const struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 const struct sctp_chunk *chunk);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +000074static void sctp_send_stale_cookie_err(struct net *net,
75 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 const struct sctp_association *asoc,
77 const struct sctp_chunk *chunk,
78 sctp_cmd_seq_t *commands,
79 struct sctp_chunk *err_chunk);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +000080static sctp_disposition_t sctp_sf_do_5_2_6_stale(struct net *net,
81 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 const struct sctp_association *asoc,
83 const sctp_subtype_t type,
84 void *arg,
85 sctp_cmd_seq_t *commands);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +000086static sctp_disposition_t sctp_sf_shut_8_4_5(struct net *net,
87 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 const struct sctp_association *asoc,
89 const sctp_subtype_t type,
90 void *arg,
91 sctp_cmd_seq_t *commands);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +000092static sctp_disposition_t sctp_sf_tabort_8_4_8(struct net *net,
93 const struct sctp_endpoint *ep,
Vlad Yasevichece25df2007-09-07 16:30:54 -040094 const struct sctp_association *asoc,
95 const sctp_subtype_t type,
96 void *arg,
97 sctp_cmd_seq_t *commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk);
99
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000100static sctp_disposition_t sctp_stop_t1_and_abort(struct net *net,
101 sctp_cmd_seq_t *commands,
Al Virof94c0192006-11-20 17:00:25 -0800102 __be16 error, int sk_err,
Adrian Bunk52c1da32005-06-23 22:05:33 -0700103 const struct sctp_association *asoc,
104 struct sctp_transport *transport);
105
Wei Yongjunaecedea2007-08-02 16:57:44 +0800106static sctp_disposition_t sctp_sf_abort_violation(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000107 struct net *net,
Vlad Yasevichece25df2007-09-07 16:30:54 -0400108 const struct sctp_endpoint *ep,
Wei Yongjunaecedea2007-08-02 16:57:44 +0800109 const struct sctp_association *asoc,
110 void *arg,
111 sctp_cmd_seq_t *commands,
112 const __u8 *payload,
113 const size_t paylen);
114
Adrian Bunk52c1da32005-06-23 22:05:33 -0700115static sctp_disposition_t sctp_sf_violation_chunklen(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000116 struct net *net,
Adrian Bunk52c1da32005-06-23 22:05:33 -0700117 const struct sctp_endpoint *ep,
118 const struct sctp_association *asoc,
119 const sctp_subtype_t type,
120 void *arg,
121 sctp_cmd_seq_t *commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122
Wei Yongjun6f4c6182007-09-19 17:19:52 +0800123static sctp_disposition_t sctp_sf_violation_paramlen(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000124 struct net *net,
Wei Yongjun6f4c6182007-09-19 17:19:52 +0800125 const struct sctp_endpoint *ep,
126 const struct sctp_association *asoc,
127 const sctp_subtype_t type,
Wei Yongjunba016672008-09-30 05:32:24 -0700128 void *arg, void *ext,
Wei Yongjun6f4c6182007-09-19 17:19:52 +0800129 sctp_cmd_seq_t *commands);
130
Wei Yongjunaecedea2007-08-02 16:57:44 +0800131static sctp_disposition_t sctp_sf_violation_ctsn(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000132 struct net *net,
Wei Yongjunaecedea2007-08-02 16:57:44 +0800133 const struct sctp_endpoint *ep,
134 const struct sctp_association *asoc,
135 const sctp_subtype_t type,
136 void *arg,
137 sctp_cmd_seq_t *commands);
138
Vlad Yasevichece25df2007-09-07 16:30:54 -0400139static sctp_disposition_t sctp_sf_violation_chunk(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000140 struct net *net,
Vlad Yasevichece25df2007-09-07 16:30:54 -0400141 const struct sctp_endpoint *ep,
142 const struct sctp_association *asoc,
143 const sctp_subtype_t type,
144 void *arg,
145 sctp_cmd_seq_t *commands);
146
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000147static sctp_ierror_t sctp_sf_authenticate(struct net *net,
148 const struct sctp_endpoint *ep,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700149 const struct sctp_association *asoc,
150 const sctp_subtype_t type,
151 struct sctp_chunk *chunk);
152
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000153static sctp_disposition_t __sctp_sf_do_9_1_abort(struct net *net,
154 const struct sctp_endpoint *ep,
Vlad Yasevich75205f42007-12-20 14:12:59 -0800155 const struct sctp_association *asoc,
156 const sctp_subtype_t type,
157 void *arg,
158 sctp_cmd_seq_t *commands);
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160/* Small helper function that checks if the chunk length
161 * is of the appropriate length. The 'required_length' argument
162 * is set to be the size of a specific chunk we are testing.
163 * Return Values: 1 = Valid length
164 * 0 = Invalid length
165 *
166 */
167static inline int
168sctp_chunk_length_valid(struct sctp_chunk *chunk,
169 __u16 required_length)
170{
171 __u16 chunk_length = ntohs(chunk->chunk_hdr->length);
172
Daniel Borkmann26b87c72014-10-09 22:55:33 +0200173 /* Previously already marked? */
174 if (unlikely(chunk->pdiscard))
175 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 if (unlikely(chunk_length < required_length))
177 return 0;
178
179 return 1;
180}
181
182/**********************************************************
183 * These are the state functions for handling chunk events.
184 **********************************************************/
185
186/*
187 * Process the final SHUTDOWN COMPLETE.
188 *
189 * Section: 4 (C) (diagram), 9.2
190 * Upon reception of the SHUTDOWN COMPLETE chunk the endpoint will verify
191 * that it is in SHUTDOWN-ACK-SENT state, if it is not the chunk should be
192 * discarded. If the endpoint is in the SHUTDOWN-ACK-SENT state the endpoint
193 * should stop the T2-shutdown timer and remove all knowledge of the
194 * association (and thus the association enters the CLOSED state).
195 *
Jerome Forissier047a2422005-04-28 11:58:43 -0700196 * Verification Tag: 8.5.1(C), sctpimpguide 2.41.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 * C) Rules for packet carrying SHUTDOWN COMPLETE:
198 * ...
Jerome Forissier047a2422005-04-28 11:58:43 -0700199 * - The receiver of a SHUTDOWN COMPLETE shall accept the packet
200 * if the Verification Tag field of the packet matches its own tag and
201 * the T bit is not set
202 * OR
203 * it is set to its peer's tag and the T bit is set in the Chunk
204 * Flags.
205 * Otherwise, the receiver MUST silently discard the packet
206 * and take no further action. An endpoint MUST ignore the
207 * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 *
209 * Inputs
210 * (endpoint, asoc, chunk)
211 *
212 * Outputs
213 * (asoc, reply_msg, msg_up, timers, counters)
214 *
215 * The return value is the disposition of the chunk.
216 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000217sctp_disposition_t sctp_sf_do_4_C(struct net *net,
218 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 const struct sctp_association *asoc,
220 const sctp_subtype_t type,
221 void *arg,
222 sctp_cmd_seq_t *commands)
223{
224 struct sctp_chunk *chunk = arg;
225 struct sctp_ulpevent *ev;
226
Vlad Yasevichece25df2007-09-07 16:30:54 -0400227 if (!sctp_vtag_verify_either(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000228 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Vlad Yasevichece25df2007-09-07 16:30:54 -0400229
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 /* RFC 2960 6.10 Bundling
231 *
232 * An endpoint MUST NOT bundle INIT, INIT ACK or
233 * SHUTDOWN COMPLETE with any other chunks.
234 */
235 if (!chunk->singleton)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000236 return sctp_sf_violation_chunk(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237
Vlad Yasevichece25df2007-09-07 16:30:54 -0400238 /* Make sure that the SHUTDOWN_COMPLETE chunk has a valid length. */
239 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000240 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -0400241 commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242
243 /* RFC 2960 10.2 SCTP-to-ULP
244 *
245 * H) SHUTDOWN COMPLETE notification
246 *
247 * When SCTP completes the shutdown procedures (section 9.2) this
248 * notification is passed to the upper layer.
249 */
250 ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP,
Vlad Yasevicha5a35e72007-03-23 11:34:08 -0700251 0, 0, 0, NULL, GFP_ATOMIC);
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700252 if (ev)
253 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900254 SCTP_ULPEVENT(ev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
256 /* Upon reception of the SHUTDOWN COMPLETE chunk the endpoint
257 * will verify that it is in SHUTDOWN-ACK-SENT state, if it is
258 * not the chunk should be discarded. If the endpoint is in
259 * the SHUTDOWN-ACK-SENT state the endpoint should stop the
260 * T2-shutdown timer and remove all knowledge of the
261 * association (and thus the association enters the CLOSED
262 * state).
263 */
264 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
265 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
266
267 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
268 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
269
270 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
271 SCTP_STATE(SCTP_STATE_CLOSED));
272
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000273 SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS);
274 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275
276 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
277
278 return SCTP_DISPOSITION_DELETE_TCB;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279}
280
281/*
282 * Respond to a normal INIT chunk.
283 * We are the side that is being asked for an association.
284 *
285 * Section: 5.1 Normal Establishment of an Association, B
286 * B) "Z" shall respond immediately with an INIT ACK chunk. The
287 * destination IP address of the INIT ACK MUST be set to the source
288 * IP address of the INIT to which this INIT ACK is responding. In
289 * the response, besides filling in other parameters, "Z" must set the
290 * Verification Tag field to Tag_A, and also provide its own
291 * Verification Tag (Tag_Z) in the Initiate Tag field.
292 *
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900293 * Verification Tag: Must be 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 *
295 * Inputs
296 * (endpoint, asoc, chunk)
297 *
298 * Outputs
299 * (asoc, reply_msg, msg_up, timers, counters)
300 *
301 * The return value is the disposition of the chunk.
302 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000303sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
304 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 const struct sctp_association *asoc,
306 const sctp_subtype_t type,
307 void *arg,
308 sctp_cmd_seq_t *commands)
309{
310 struct sctp_chunk *chunk = arg;
311 struct sctp_chunk *repl;
312 struct sctp_association *new_asoc;
313 struct sctp_chunk *err_chunk;
314 struct sctp_packet *packet;
315 sctp_unrecognized_param_t *unk_param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 int len;
317
318 /* 6.10 Bundling
319 * An endpoint MUST NOT bundle INIT, INIT ACK or
320 * SHUTDOWN COMPLETE with any other chunks.
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900321 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 * IG Section 2.11.2
323 * Furthermore, we require that the receiver of an INIT chunk MUST
324 * enforce these rules by silently discarding an arriving packet
325 * with an INIT chunk that is bundled with other chunks.
326 */
327 if (!chunk->singleton)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000328 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329
330 /* If the packet is an OOTB packet which is temporarily on the
331 * control endpoint, respond with an ABORT.
332 */
Eric W. Biederman2ce95502012-08-06 08:43:06 +0000333 if (ep == sctp_sk(net->sctp.ctl_sock)->ep) {
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000334 SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000335 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Wei Yongjun8190f892008-09-08 12:13:55 +0800336 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 /* 3.1 A packet containing an INIT chunk MUST have a zero Verification
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900339 * Tag.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 */
341 if (chunk->sctp_hdr->vtag != 0)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000342 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343
344 /* Make sure that the INIT chunk has a valid length.
345 * Normally, this would cause an ABORT with a Protocol Violation
346 * error, but since we don't have an association, we'll
347 * just discard the packet.
348 */
349 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000350 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351
Vlad Yasevichbec96402009-07-30 18:08:28 -0400352 /* If the INIT is coming toward a closing socket, we'll send back
353 * and ABORT. Essentially, this catches the race of INIT being
354 * backloged to the socket at the same time as the user isses close().
355 * Since the socket and all its associations are going away, we
356 * can treat this OOTB
357 */
358 if (sctp_sstate(ep->base.sk, CLOSING))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000359 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Vlad Yasevichbec96402009-07-30 18:08:28 -0400360
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 /* Verify the INIT chunk before processing it. */
362 err_chunk = NULL;
Vlad Yasevichb14878c2014-04-17 17:26:50 +0200363 if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 (sctp_init_chunk_t *)chunk->chunk_hdr, chunk,
365 &err_chunk)) {
366 /* This chunk contains fatal error. It is to be discarded.
367 * Send an ABORT, with causes if there is any.
368 */
369 if (err_chunk) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000370 packet = sctp_abort_pkt_new(net, ep, asoc, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 (__u8 *)(err_chunk->chunk_hdr) +
372 sizeof(sctp_chunkhdr_t),
373 ntohs(err_chunk->chunk_hdr->length) -
374 sizeof(sctp_chunkhdr_t));
375
376 sctp_chunk_free(err_chunk);
377
378 if (packet) {
379 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
380 SCTP_PACKET(packet));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000381 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 return SCTP_DISPOSITION_CONSUME;
383 } else {
384 return SCTP_DISPOSITION_NOMEM;
385 }
386 } else {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000387 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 commands);
389 }
390 }
391
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900392 /* Grab the INIT header. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 chunk->subh.init_hdr = (sctp_inithdr_t *)chunk->skb->data;
394
395 /* Tag the variable length parameters. */
396 chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t));
397
398 new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC);
399 if (!new_asoc)
400 goto nomem;
401
Vlad Yasevich409b95a2009-11-10 08:57:34 +0000402 if (sctp_assoc_set_bind_addr_from_ep(new_asoc,
403 sctp_scope(sctp_source(chunk)),
404 GFP_ATOMIC) < 0)
405 goto nomem_init;
406
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 /* The call, sctp_process_init(), can fail on memory allocation. */
Wei Yongjunde6becd2011-04-19 21:30:51 +0000408 if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 (sctp_init_chunk_t *)chunk->chunk_hdr,
410 GFP_ATOMIC))
411 goto nomem_init;
412
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 /* B) "Z" shall respond immediately with an INIT ACK chunk. */
414
415 /* If there are errors need to be reported for unknown parameters,
416 * make sure to reserve enough room in the INIT ACK for them.
417 */
418 len = 0;
419 if (err_chunk)
420 len = ntohs(err_chunk->chunk_hdr->length) -
421 sizeof(sctp_chunkhdr_t);
422
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len);
424 if (!repl)
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700425 goto nomem_init;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426
427 /* If there are errors need to be reported for unknown parameters,
428 * include them in the outgoing INIT ACK as "Unrecognized parameter"
429 * parameter.
430 */
431 if (err_chunk) {
432 /* Get the "Unrecognized parameter" parameter(s) out of the
433 * ERROR chunk generated by sctp_verify_init(). Since the
434 * error cause code for "unknown parameter" and the
435 * "Unrecognized parameter" type is the same, we can
436 * construct the parameters in INIT ACK by copying the
437 * ERROR causes over.
438 */
439 unk_param = (sctp_unrecognized_param_t *)
440 ((__u8 *)(err_chunk->chunk_hdr) +
441 sizeof(sctp_chunkhdr_t));
442 /* Replace the cause code with the "Unrecognized parameter"
443 * parameter type.
444 */
445 sctp_addto_chunk(repl, len, unk_param);
446 sctp_chunk_free(err_chunk);
447 }
448
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700449 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
450
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
452
453 /*
454 * Note: After sending out INIT ACK with the State Cookie parameter,
455 * "Z" MUST NOT allocate any resources, nor keep any states for the
456 * new association. Otherwise, "Z" will be vulnerable to resource
457 * attacks.
458 */
459 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
460
461 return SCTP_DISPOSITION_DELETE_TCB;
462
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463nomem_init:
464 sctp_association_free(new_asoc);
465nomem:
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700466 if (err_chunk)
467 sctp_chunk_free(err_chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 return SCTP_DISPOSITION_NOMEM;
469}
470
471/*
472 * Respond to a normal INIT ACK chunk.
473 * We are the side that is initiating the association.
474 *
475 * Section: 5.1 Normal Establishment of an Association, C
476 * C) Upon reception of the INIT ACK from "Z", "A" shall stop the T1-init
477 * timer and leave COOKIE-WAIT state. "A" shall then send the State
478 * Cookie received in the INIT ACK chunk in a COOKIE ECHO chunk, start
479 * the T1-cookie timer, and enter the COOKIE-ECHOED state.
480 *
481 * Note: The COOKIE ECHO chunk can be bundled with any pending outbound
482 * DATA chunks, but it MUST be the first chunk in the packet and
483 * until the COOKIE ACK is returned the sender MUST NOT send any
484 * other packets to the peer.
485 *
486 * Verification Tag: 3.3.3
487 * If the value of the Initiate Tag in a received INIT ACK chunk is
488 * found to be 0, the receiver MUST treat it as an error and close the
489 * association by transmitting an ABORT.
490 *
491 * Inputs
492 * (endpoint, asoc, chunk)
493 *
494 * Outputs
495 * (asoc, reply_msg, msg_up, timers, counters)
496 *
497 * The return value is the disposition of the chunk.
498 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000499sctp_disposition_t sctp_sf_do_5_1C_ack(struct net *net,
500 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 const struct sctp_association *asoc,
502 const sctp_subtype_t type,
503 void *arg,
504 sctp_cmd_seq_t *commands)
505{
506 struct sctp_chunk *chunk = arg;
507 sctp_init_chunk_t *initchunk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 struct sctp_chunk *err_chunk;
509 struct sctp_packet *packet;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
511 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000512 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 /* 6.10 Bundling
515 * An endpoint MUST NOT bundle INIT, INIT ACK or
516 * SHUTDOWN COMPLETE with any other chunks.
517 */
518 if (!chunk->singleton)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000519 return sctp_sf_violation_chunk(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520
Vlad Yasevichece25df2007-09-07 16:30:54 -0400521 /* Make sure that the INIT-ACK chunk has a valid length */
522 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_initack_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000523 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -0400524 commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 /* Grab the INIT header. */
526 chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data;
527
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 /* Verify the INIT chunk before processing it. */
529 err_chunk = NULL;
Vlad Yasevichb14878c2014-04-17 17:26:50 +0200530 if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 (sctp_init_chunk_t *)chunk->chunk_hdr, chunk,
532 &err_chunk)) {
533
Vlad Yasevich853f4b52008-01-20 06:10:46 -0800534 sctp_error_t error = SCTP_ERROR_NO_RESOURCE;
535
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 /* This chunk contains fatal error. It is to be discarded.
Vlad Yasevichd6701192007-12-20 14:13:31 -0800537 * Send an ABORT, with causes. If there are no causes,
538 * then there wasn't enough memory. Just terminate
539 * the association.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 */
541 if (err_chunk) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000542 packet = sctp_abort_pkt_new(net, ep, asoc, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 (__u8 *)(err_chunk->chunk_hdr) +
544 sizeof(sctp_chunkhdr_t),
545 ntohs(err_chunk->chunk_hdr->length) -
546 sizeof(sctp_chunkhdr_t));
547
548 sctp_chunk_free(err_chunk);
549
550 if (packet) {
551 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
552 SCTP_PACKET(packet));
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000553 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Sridhar Samudrala8de8c872006-05-19 10:58:12 -0700554 error = SCTP_ERROR_INV_PARAM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 }
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700557
558 /* SCTP-AUTH, Section 6.3:
559 * It should be noted that if the receiver wants to tear
560 * down an association in an authenticated way only, the
561 * handling of malformed packets should not result in
562 * tearing down the association.
563 *
564 * This means that if we only want to abort associations
565 * in an authenticated way (i.e AUTH+ABORT), then we
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300566 * can't destroy this association just because the packet
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700567 * was malformed.
568 */
569 if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000570 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700571
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000572 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
573 return sctp_stop_t1_and_abort(net, commands, error, ECONNREFUSED,
Sridhar Samudrala8de8c872006-05-19 10:58:12 -0700574 asoc, chunk->transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 }
576
577 /* Tag the variable length parameters. Note that we never
578 * convert the parameters in an INIT chunk.
579 */
580 chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t));
581
582 initchunk = (sctp_init_chunk_t *) chunk->chunk_hdr;
583
584 sctp_add_cmd_sf(commands, SCTP_CMD_PEER_INIT,
585 SCTP_PEER_INIT(initchunk));
586
Frank Filz3f7a87d2005-06-20 13:14:57 -0700587 /* Reset init error count upon receipt of INIT-ACK. */
588 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL());
589
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 /* 5.1 C) "A" shall stop the T1-init timer and leave
591 * COOKIE-WAIT state. "A" shall then ... start the T1-cookie
592 * timer, and enter the COOKIE-ECHOED state.
593 */
594 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
595 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
596 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
597 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
598 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
599 SCTP_STATE(SCTP_STATE_COOKIE_ECHOED));
600
Vlad Yasevich730fc3d2007-09-16 19:32:11 -0700601 /* SCTP-AUTH: genereate the assocition shared keys so that
602 * we can potentially signe the COOKIE-ECHO.
603 */
604 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_SHKEY, SCTP_NULL());
605
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 /* 5.1 C) "A" shall then send the State Cookie received in the
607 * INIT ACK chunk in a COOKIE ECHO chunk, ...
608 */
609 /* If there is any errors to report, send the ERROR chunk generated
610 * for unknown parameters as well.
611 */
612 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_COOKIE_ECHO,
613 SCTP_CHUNK(err_chunk));
614
615 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616}
617
618/*
619 * Respond to a normal COOKIE ECHO chunk.
620 * We are the side that is being asked for an association.
621 *
622 * Section: 5.1 Normal Establishment of an Association, D
623 * D) Upon reception of the COOKIE ECHO chunk, Endpoint "Z" will reply
624 * with a COOKIE ACK chunk after building a TCB and moving to
625 * the ESTABLISHED state. A COOKIE ACK chunk may be bundled with
626 * any pending DATA chunks (and/or SACK chunks), but the COOKIE ACK
627 * chunk MUST be the first chunk in the packet.
628 *
629 * IMPLEMENTATION NOTE: An implementation may choose to send the
630 * Communication Up notification to the SCTP user upon reception
631 * of a valid COOKIE ECHO chunk.
632 *
633 * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules
634 * D) Rules for packet carrying a COOKIE ECHO
635 *
636 * - When sending a COOKIE ECHO, the endpoint MUST use the value of the
637 * Initial Tag received in the INIT ACK.
638 *
639 * - The receiver of a COOKIE ECHO follows the procedures in Section 5.
640 *
641 * Inputs
642 * (endpoint, asoc, chunk)
643 *
644 * Outputs
645 * (asoc, reply_msg, msg_up, timers, counters)
646 *
647 * The return value is the disposition of the chunk.
648 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000649sctp_disposition_t sctp_sf_do_5_1D_ce(struct net *net,
650 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 const struct sctp_association *asoc,
652 const sctp_subtype_t type, void *arg,
653 sctp_cmd_seq_t *commands)
654{
655 struct sctp_chunk *chunk = arg;
656 struct sctp_association *new_asoc;
657 sctp_init_chunk_t *peer_init;
658 struct sctp_chunk *repl;
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700659 struct sctp_ulpevent *ev, *ai_ev = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 int error = 0;
661 struct sctp_chunk *err_chk_p;
Vlad Yasevich609ee462007-08-31 03:10:59 +0900662 struct sock *sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663
664 /* If the packet is an OOTB packet which is temporarily on the
665 * control endpoint, respond with an ABORT.
666 */
Eric W. Biederman2ce95502012-08-06 08:43:06 +0000667 if (ep == sctp_sk(net->sctp.ctl_sock)->ep) {
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000668 SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000669 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Wei Yongjun8190f892008-09-08 12:13:55 +0800670 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671
672 /* Make sure that the COOKIE_ECHO chunk has a valid length.
673 * In this case, we check that we have enough for at least a
674 * chunk header. More detailed verification is done
675 * in sctp_unpack_cookie().
676 */
677 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000678 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679
Vlad Yasevich609ee462007-08-31 03:10:59 +0900680 /* If the endpoint is not listening or if the number of associations
681 * on the TCP-style socket exceed the max backlog, respond with an
682 * ABORT.
683 */
684 sk = ep->base.sk;
685 if (!sctp_sstate(sk, LISTENING) ||
686 (sctp_style(sk, TCP) && sk_acceptq_is_full(sk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000687 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Vlad Yasevich609ee462007-08-31 03:10:59 +0900688
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 /* "Decode" the chunk. We have no optional parameters so we
690 * are in good shape.
691 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900692 chunk->subh.cookie_hdr =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 (struct sctp_signed_cookie *)chunk->skb->data;
Sridhar Samudrala62b08082006-05-05 17:04:43 -0700694 if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) -
695 sizeof(sctp_chunkhdr_t)))
696 goto nomem;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697
698 /* 5.1 D) Upon reception of the COOKIE ECHO chunk, Endpoint
699 * "Z" will reply with a COOKIE ACK chunk after building a TCB
700 * and moving to the ESTABLISHED state.
701 */
702 new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error,
703 &err_chk_p);
704
705 /* FIXME:
706 * If the re-build failed, what is the proper error path
707 * from here?
708 *
709 * [We should abort the association. --piggy]
710 */
711 if (!new_asoc) {
712 /* FIXME: Several errors are possible. A bad cookie should
713 * be silently discarded, but think about logging it too.
714 */
715 switch (error) {
716 case -SCTP_IERROR_NOMEM:
717 goto nomem;
718
719 case -SCTP_IERROR_STALE_COOKIE:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000720 sctp_send_stale_cookie_err(net, ep, asoc, chunk, commands,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 err_chk_p);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000722 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723
724 case -SCTP_IERROR_BAD_SIG:
725 default:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000726 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700727 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 }
729
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700731 /* Delay state machine commands until later.
732 *
733 * Re-build the bind address for the association is done in
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 * the sctp_unpack_cookie() already.
735 */
736 /* This is a brand-new association, so these are not yet side
737 * effects--it is safe to run them here.
738 */
739 peer_init = &chunk->subh.cookie_hdr->c.peer_init[0];
740
Wei Yongjunde6becd2011-04-19 21:30:51 +0000741 if (!sctp_process_init(new_asoc, chunk,
Al Viro6a1e5f32006-11-20 17:12:25 -0800742 &chunk->subh.cookie_hdr->c.peer_addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 peer_init, GFP_ATOMIC))
744 goto nomem_init;
745
Vlad Yasevich730fc3d2007-09-16 19:32:11 -0700746 /* SCTP-AUTH: Now that we've populate required fields in
747 * sctp_process_init, set up the assocaition shared keys as
748 * necessary so that we can potentially authenticate the ACK
749 */
750 error = sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC);
751 if (error)
752 goto nomem_init;
753
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700754 /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo
755 * is supposed to be authenticated and we have to do delayed
756 * authentication. We've just recreated the association using
757 * the information in the cookie and now it's much easier to
758 * do the authentication.
759 */
760 if (chunk->auth_chunk) {
761 struct sctp_chunk auth;
762 sctp_ierror_t ret;
763
Daniel Borkmannec0223e2014-03-03 17:23:04 +0100764 /* Make sure that we and the peer are AUTH capable */
765 if (!net->sctp.auth_enable || !new_asoc->peer.auth_capable) {
Daniel Borkmannec0223e2014-03-03 17:23:04 +0100766 sctp_association_free(new_asoc);
767 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
768 }
769
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700770 /* set-up our fake chunk so that we can process it */
771 auth.skb = chunk->auth_chunk;
772 auth.asoc = chunk->asoc;
773 auth.sctp_hdr = chunk->sctp_hdr;
774 auth.chunk_hdr = (sctp_chunkhdr_t *)skb_push(chunk->auth_chunk,
775 sizeof(sctp_chunkhdr_t));
776 skb_pull(chunk->auth_chunk, sizeof(sctp_chunkhdr_t));
777 auth.transport = chunk->transport;
778
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000779 ret = sctp_sf_authenticate(net, ep, new_asoc, type, &auth);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700780 if (ret != SCTP_IERROR_NO_ERROR) {
781 sctp_association_free(new_asoc);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000782 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -0700783 }
784 }
785
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 repl = sctp_make_cookie_ack(new_asoc, chunk);
787 if (!repl)
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700788 goto nomem_init;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
790 /* RFC 2960 5.1 Normal Establishment of an Association
791 *
792 * D) IMPLEMENTATION NOTE: An implementation may choose to
793 * send the Communication Up notification to the SCTP user
794 * upon reception of a valid COOKIE ECHO chunk.
795 */
796 ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0,
797 new_asoc->c.sinit_num_ostreams,
798 new_asoc->c.sinit_max_instreams,
Vlad Yasevicha5a35e72007-03-23 11:34:08 -0700799 NULL, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 if (!ev)
801 goto nomem_ev;
802
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900803 /* Sockets API Draft Section 5.3.1.6
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -0800804 * When a peer sends a Adaptation Layer Indication parameter , SCTP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 * delivers this notification to inform the application that of the
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -0800806 * peers requested adaptation layer.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807 */
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -0800808 if (new_asoc->peer.adaptation_ind) {
809 ai_ev = sctp_ulpevent_make_adaptation_indication(new_asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 GFP_ATOMIC);
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700811 if (!ai_ev)
812 goto nomem_aiev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 }
814
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700815 /* Add all the state machine commands now since we've created
816 * everything. This way we don't introduce memory corruptions
817 * during side-effect processing and correclty count established
818 * associations.
819 */
820 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
821 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
822 SCTP_STATE(SCTP_STATE_ESTABLISHED));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000823 SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB);
824 SCTP_INC_STATS(net, SCTP_MIB_PASSIVEESTABS);
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700825 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL());
826
Neil Horman9f70f462013-12-10 06:48:15 -0500827 if (new_asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE])
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700828 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
829 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
830
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700831 /* This will send the COOKIE ACK */
832 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
833
834 /* Queue the ASSOC_CHANGE event */
835 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
836
837 /* Send up the Adaptation Layer Indication event */
838 if (ai_ev)
839 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
840 SCTP_ULPEVENT(ai_ev));
841
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 return SCTP_DISPOSITION_CONSUME;
843
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -0700844nomem_aiev:
845 sctp_ulpevent_free(ev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846nomem_ev:
847 sctp_chunk_free(repl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848nomem_init:
849 sctp_association_free(new_asoc);
850nomem:
851 return SCTP_DISPOSITION_NOMEM;
852}
853
854/*
855 * Respond to a normal COOKIE ACK chunk.
Marcelo Ricardo Leitnerb52effd2015-07-17 13:50:21 -0300856 * We are the side that is asking for an association.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 *
858 * RFC 2960 5.1 Normal Establishment of an Association
859 *
860 * E) Upon reception of the COOKIE ACK, endpoint "A" will move from the
861 * COOKIE-ECHOED state to the ESTABLISHED state, stopping the T1-cookie
862 * timer. It may also notify its ULP about the successful
863 * establishment of the association with a Communication Up
864 * notification (see Section 10).
865 *
866 * Verification Tag:
867 * Inputs
868 * (endpoint, asoc, chunk)
869 *
870 * Outputs
871 * (asoc, reply_msg, msg_up, timers, counters)
872 *
873 * The return value is the disposition of the chunk.
874 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000875sctp_disposition_t sctp_sf_do_5_1E_ca(struct net *net,
876 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 const struct sctp_association *asoc,
878 const sctp_subtype_t type, void *arg,
879 sctp_cmd_seq_t *commands)
880{
881 struct sctp_chunk *chunk = arg;
882 struct sctp_ulpevent *ev;
883
884 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000885 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886
887 /* Verify that the chunk length for the COOKIE-ACK is OK.
888 * If we don't do this, any bundled chunks may be junked.
889 */
890 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000891 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 commands);
893
894 /* Reset init error count upon receipt of COOKIE-ACK,
895 * to avoid problems with the managemement of this
896 * counter in stale cookie situations when a transition back
897 * from the COOKIE-ECHOED state to the COOKIE-WAIT
898 * state is performed.
899 */
Frank Filz3f7a87d2005-06-20 13:14:57 -0700900 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL());
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
902 /* RFC 2960 5.1 Normal Establishment of an Association
903 *
904 * E) Upon reception of the COOKIE ACK, endpoint "A" will move
905 * from the COOKIE-ECHOED state to the ESTABLISHED state,
906 * stopping the T1-cookie timer.
907 */
908 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
909 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
910 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
911 SCTP_STATE(SCTP_STATE_ESTABLISHED));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000912 SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB);
913 SCTP_INC_STATS(net, SCTP_MIB_ACTIVEESTABS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL());
Neil Horman9f70f462013-12-10 06:48:15 -0500915 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE])
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
917 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918
919 /* It may also notify its ULP about the successful
920 * establishment of the association with a Communication Up
921 * notification (see Section 10).
922 */
923 ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP,
924 0, asoc->c.sinit_num_ostreams,
925 asoc->c.sinit_max_instreams,
Vlad Yasevicha5a35e72007-03-23 11:34:08 -0700926 NULL, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
928 if (!ev)
929 goto nomem;
930
931 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
932
933 /* Sockets API Draft Section 5.3.1.6
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -0800934 * When a peer sends a Adaptation Layer Indication parameter , SCTP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935 * delivers this notification to inform the application that of the
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -0800936 * peers requested adaptation layer.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700937 */
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -0800938 if (asoc->peer.adaptation_ind) {
939 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940 if (!ev)
941 goto nomem;
942
943 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
944 SCTP_ULPEVENT(ev));
945 }
946
947 return SCTP_DISPOSITION_CONSUME;
948nomem:
949 return SCTP_DISPOSITION_NOMEM;
950}
951
952/* Generate and sendout a heartbeat packet. */
953static sctp_disposition_t sctp_sf_heartbeat(const struct sctp_endpoint *ep,
954 const struct sctp_association *asoc,
955 const sctp_subtype_t type,
956 void *arg,
957 sctp_cmd_seq_t *commands)
958{
959 struct sctp_transport *transport = (struct sctp_transport *) arg;
960 struct sctp_chunk *reply;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961
962 /* Send a heartbeat to our peer. */
Wei Yongjun92c73af2011-04-19 21:31:47 +0000963 reply = sctp_make_heartbeat(asoc, transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964 if (!reply)
965 return SCTP_DISPOSITION_NOMEM;
966
967 /* Set rto_pending indicating that an RTT measurement
968 * is started with this heartbeat chunk.
969 */
970 sctp_add_cmd_sf(commands, SCTP_CMD_RTO_PENDING,
971 SCTP_TRANSPORT(transport));
972
973 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
974 return SCTP_DISPOSITION_CONSUME;
975}
976
977/* Generate a HEARTBEAT packet on the given transport. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +0000978sctp_disposition_t sctp_sf_sendbeat_8_3(struct net *net,
979 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 const struct sctp_association *asoc,
981 const sctp_subtype_t type,
982 void *arg,
983 sctp_cmd_seq_t *commands)
984{
985 struct sctp_transport *transport = (struct sctp_transport *) arg;
986
Vlad Yasevichb9f84782009-08-26 09:36:25 -0400987 if (asoc->overall_error_count >= asoc->max_retrans) {
Sridhar Samudrala8de8c872006-05-19 10:58:12 -0700988 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
989 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990 /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
991 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -0800992 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +0000993 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
994 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 return SCTP_DISPOSITION_DELETE_TCB;
996 }
997
998 /* Section 3.3.5.
999 * The Sender-specific Heartbeat Info field should normally include
1000 * information about the sender's current time when this HEARTBEAT
1001 * chunk is sent and the destination transport address to which this
1002 * HEARTBEAT is sent (see Section 8.3).
1003 */
1004
Frank Filz52ccb8e2005-12-22 11:36:46 -08001005 if (transport->param_flags & SPP_HB_ENABLE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 if (SCTP_DISPOSITION_NOMEM ==
1007 sctp_sf_heartbeat(ep, asoc, type, arg,
1008 commands))
1009 return SCTP_DISPOSITION_NOMEM;
Vlad Yasevich245cba72009-11-23 15:53:58 -05001010
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 /* Set transport error counter and association error counter
1012 * when sending heartbeat.
1013 */
Vlad Yasevich7e990132009-03-02 09:46:14 +00001014 sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 SCTP_TRANSPORT(transport));
1016 }
Vlad Yasevich245cba72009-11-23 15:53:58 -05001017 sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_IDLE,
1018 SCTP_TRANSPORT(transport));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMER_UPDATE,
1020 SCTP_TRANSPORT(transport));
1021
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001022 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001023}
1024
1025/*
1026 * Process an heartbeat request.
1027 *
1028 * Section: 8.3 Path Heartbeat
1029 * The receiver of the HEARTBEAT should immediately respond with a
1030 * HEARTBEAT ACK that contains the Heartbeat Information field copied
1031 * from the received HEARTBEAT chunk.
1032 *
1033 * Verification Tag: 8.5 Verification Tag [Normal verification]
1034 * When receiving an SCTP packet, the endpoint MUST ensure that the
1035 * value in the Verification Tag field of the received SCTP packet
1036 * matches its own Tag. If the received Verification Tag value does not
1037 * match the receiver's own tag value, the receiver shall silently
1038 * discard the packet and shall not process it any further except for
1039 * those cases listed in Section 8.5.1 below.
1040 *
1041 * Inputs
1042 * (endpoint, asoc, chunk)
1043 *
1044 * Outputs
1045 * (asoc, reply_msg, msg_up, timers, counters)
1046 *
1047 * The return value is the disposition of the chunk.
1048 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001049sctp_disposition_t sctp_sf_beat_8_3(struct net *net,
1050 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 const struct sctp_association *asoc,
1052 const sctp_subtype_t type,
1053 void *arg,
1054 sctp_cmd_seq_t *commands)
1055{
Thomas Graf06a31e22012-11-30 02:16:27 +00001056 sctp_paramhdr_t *param_hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057 struct sctp_chunk *chunk = arg;
1058 struct sctp_chunk *reply;
1059 size_t paylen = 0;
1060
1061 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001062 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001063
1064 /* Make sure that the HEARTBEAT chunk has a valid length. */
1065 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001066 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 commands);
1068
1069 /* 8.3 The receiver of the HEARTBEAT should immediately
1070 * respond with a HEARTBEAT ACK that contains the Heartbeat
1071 * Information field copied from the received HEARTBEAT chunk.
1072 */
1073 chunk->subh.hb_hdr = (sctp_heartbeathdr_t *) chunk->skb->data;
Thomas Graf06a31e22012-11-30 02:16:27 +00001074 param_hdr = (sctp_paramhdr_t *) chunk->subh.hb_hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 paylen = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
Thomas Graf06a31e22012-11-30 02:16:27 +00001076
1077 if (ntohs(param_hdr->length) > paylen)
1078 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
1079 param_hdr, commands);
1080
Sridhar Samudrala62b08082006-05-05 17:04:43 -07001081 if (!pskb_pull(chunk->skb, paylen))
1082 goto nomem;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083
Thomas Graf06a31e22012-11-30 02:16:27 +00001084 reply = sctp_make_heartbeat_ack(asoc, chunk, param_hdr, paylen);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085 if (!reply)
1086 goto nomem;
1087
1088 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
1089 return SCTP_DISPOSITION_CONSUME;
1090
1091nomem:
1092 return SCTP_DISPOSITION_NOMEM;
1093}
1094
1095/*
1096 * Process the returning HEARTBEAT ACK.
1097 *
1098 * Section: 8.3 Path Heartbeat
1099 * Upon the receipt of the HEARTBEAT ACK, the sender of the HEARTBEAT
1100 * should clear the error counter of the destination transport
1101 * address to which the HEARTBEAT was sent, and mark the destination
1102 * transport address as active if it is not so marked. The endpoint may
1103 * optionally report to the upper layer when an inactive destination
1104 * address is marked as active due to the reception of the latest
1105 * HEARTBEAT ACK. The receiver of the HEARTBEAT ACK must also
1106 * clear the association overall error count as well (as defined
1107 * in section 8.1).
1108 *
1109 * The receiver of the HEARTBEAT ACK should also perform an RTT
1110 * measurement for that destination transport address using the time
1111 * value carried in the HEARTBEAT ACK chunk.
1112 *
1113 * Verification Tag: 8.5 Verification Tag [Normal verification]
1114 *
1115 * Inputs
1116 * (endpoint, asoc, chunk)
1117 *
1118 * Outputs
1119 * (asoc, reply_msg, msg_up, timers, counters)
1120 *
1121 * The return value is the disposition of the chunk.
1122 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001123sctp_disposition_t sctp_sf_backbeat_8_3(struct net *net,
1124 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125 const struct sctp_association *asoc,
1126 const sctp_subtype_t type,
1127 void *arg,
1128 sctp_cmd_seq_t *commands)
1129{
1130 struct sctp_chunk *chunk = arg;
1131 union sctp_addr from_addr;
1132 struct sctp_transport *link;
1133 sctp_sender_hb_info_t *hbinfo;
1134 unsigned long max_interval;
1135
1136 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001137 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138
1139 /* Make sure that the HEARTBEAT-ACK chunk has a valid length. */
Wei Yongjundadb50c2009-08-22 11:27:37 +08001140 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t) +
1141 sizeof(sctp_sender_hb_info_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001142 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143 commands);
1144
1145 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
Vladislav Yasevicha6012662006-05-19 14:25:53 -07001146 /* Make sure that the length of the parameter is what we expect */
1147 if (ntohs(hbinfo->param_hdr.length) !=
1148 sizeof(sctp_sender_hb_info_t)) {
1149 return SCTP_DISPOSITION_DISCARD;
1150 }
1151
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 from_addr = hbinfo->daddr;
Al Viro63de08f2006-11-20 17:07:25 -08001153 link = sctp_assoc_lookup_paddr(asoc, &from_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154
1155 /* This should never happen, but lets log it if so. */
Frank Filz3f7a87d2005-06-20 13:14:57 -07001156 if (unlikely(!link)) {
1157 if (from_addr.sa.sa_family == AF_INET6) {
Joe Perchese87cc472012-05-13 21:56:26 +00001158 net_warn_ratelimited("%s association %p could not find address %pI6\n",
1159 __func__,
1160 asoc,
1161 &from_addr.v6.sin6_addr);
Frank Filz3f7a87d2005-06-20 13:14:57 -07001162 } else {
Joe Perchese87cc472012-05-13 21:56:26 +00001163 net_warn_ratelimited("%s association %p could not find address %pI4\n",
1164 __func__,
1165 asoc,
1166 &from_addr.v4.sin_addr.s_addr);
Frank Filz3f7a87d2005-06-20 13:14:57 -07001167 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168 return SCTP_DISPOSITION_DISCARD;
1169 }
1170
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001171 /* Validate the 64-bit random nonce. */
1172 if (hbinfo->hb_nonce != link->hb_nonce)
1173 return SCTP_DISPOSITION_DISCARD;
1174
Frank Filz52ccb8e2005-12-22 11:36:46 -08001175 max_interval = link->hbinterval + link->rto;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176
1177 /* Check if the timestamp looks valid. */
1178 if (time_after(hbinfo->sent_at, jiffies) ||
1179 time_after(jiffies, hbinfo->sent_at + max_interval)) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02001180 pr_debug("%s: HEARTBEAT ACK with invalid timestamp received "
1181 "for transport:%p\n", __func__, link);
1182
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183 return SCTP_DISPOSITION_DISCARD;
1184 }
1185
1186 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of
1187 * the HEARTBEAT should clear the error counter of the
1188 * destination transport address to which the HEARTBEAT was
1189 * sent and mark the destination transport address as active if
1190 * it is not so marked.
1191 */
1192 sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_ON, SCTP_TRANSPORT(link));
1193
1194 return SCTP_DISPOSITION_CONSUME;
1195}
1196
1197/* Helper function to send out an abort for the restart
1198 * condition.
1199 */
Eric W. Biederman2ce95502012-08-06 08:43:06 +00001200static int sctp_sf_send_restart_abort(struct net *net, union sctp_addr *ssa,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001201 struct sctp_chunk *init,
1202 sctp_cmd_seq_t *commands)
1203{
1204 int len;
1205 struct sctp_packet *pkt;
1206 union sctp_addr_param *addrparm;
1207 struct sctp_errhdr *errhdr;
1208 struct sctp_endpoint *ep;
1209 char buffer[sizeof(struct sctp_errhdr)+sizeof(union sctp_addr_param)];
1210 struct sctp_af *af = sctp_get_af_specific(ssa->v4.sin_family);
1211
1212 /* Build the error on the stack. We are way to malloc crazy
1213 * throughout the code today.
1214 */
1215 errhdr = (struct sctp_errhdr *)buffer;
1216 addrparm = (union sctp_addr_param *)errhdr->variable;
1217
1218 /* Copy into a parm format. */
1219 len = af->to_addr_param(ssa, addrparm);
1220 len += sizeof(sctp_errhdr_t);
1221
1222 errhdr->cause = SCTP_ERROR_RESTART;
1223 errhdr->length = htons(len);
1224
1225 /* Assign to the control socket. */
Eric W. Biederman2ce95502012-08-06 08:43:06 +00001226 ep = sctp_sk(net->sctp.ctl_sock)->ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227
1228 /* Association is NULL since this may be a restart attack and we
1229 * want to send back the attacker's vtag.
1230 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001231 pkt = sctp_abort_pkt_new(net, ep, NULL, init, errhdr, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232
1233 if (!pkt)
1234 goto out;
1235 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(pkt));
1236
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00001237 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238
1239 /* Discard the rest of the inbound packet. */
1240 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
1241
1242out:
1243 /* Even if there is no memory, treat as a failure so
1244 * the packet will get dropped.
1245 */
1246 return 0;
1247}
1248
Joe Perches123031c2010-09-08 11:04:21 +00001249static bool list_has_sctp_addr(const struct list_head *list,
1250 union sctp_addr *ipaddr)
1251{
1252 struct sctp_transport *addr;
1253
1254 list_for_each_entry(addr, list, transports) {
1255 if (sctp_cmp_addr_exact(ipaddr, &addr->ipaddr))
1256 return true;
1257 }
1258
1259 return false;
1260}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001261/* A restart is occurring, check to make sure no new addresses
1262 * are being added as we may be under a takeover attack.
1263 */
1264static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc,
1265 const struct sctp_association *asoc,
1266 struct sctp_chunk *init,
1267 sctp_cmd_seq_t *commands)
1268{
Eric W. Biederman2ce95502012-08-06 08:43:06 +00001269 struct net *net = sock_net(new_asoc->base.sk);
Joe Perches123031c2010-09-08 11:04:21 +00001270 struct sctp_transport *new_addr;
1271 int ret = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272
Joe Perches123031c2010-09-08 11:04:21 +00001273 /* Implementor's Guide - Section 5.2.2
Linus Torvalds1da177e2005-04-16 15:20:36 -07001274 * ...
1275 * Before responding the endpoint MUST check to see if the
1276 * unexpected INIT adds new addresses to the association. If new
1277 * addresses are added to the association, the endpoint MUST respond
1278 * with an ABORT..
1279 */
1280
1281 /* Search through all current addresses and make sure
1282 * we aren't adding any new ones.
1283 */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001284 list_for_each_entry(new_addr, &new_asoc->peer.transport_addr_list,
Joe Perches123031c2010-09-08 11:04:21 +00001285 transports) {
1286 if (!list_has_sctp_addr(&asoc->peer.transport_addr_list,
1287 &new_addr->ipaddr)) {
Eric W. Biederman2ce95502012-08-06 08:43:06 +00001288 sctp_sf_send_restart_abort(net, &new_addr->ipaddr, init,
Joe Perches123031c2010-09-08 11:04:21 +00001289 commands);
1290 ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 break;
Joe Perches123031c2010-09-08 11:04:21 +00001292 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293 }
1294
1295 /* Return success if all addresses were found. */
Joe Perches123031c2010-09-08 11:04:21 +00001296 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001297}
1298
1299/* Populate the verification/tie tags based on overlapping INIT
1300 * scenario.
1301 *
1302 * Note: Do not use in CLOSED or SHUTDOWN-ACK-SENT state.
1303 */
1304static void sctp_tietags_populate(struct sctp_association *new_asoc,
1305 const struct sctp_association *asoc)
1306{
1307 switch (asoc->state) {
1308
1309 /* 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State */
1310
1311 case SCTP_STATE_COOKIE_WAIT:
1312 new_asoc->c.my_vtag = asoc->c.my_vtag;
1313 new_asoc->c.my_ttag = asoc->c.my_vtag;
1314 new_asoc->c.peer_ttag = 0;
1315 break;
1316
1317 case SCTP_STATE_COOKIE_ECHOED:
1318 new_asoc->c.my_vtag = asoc->c.my_vtag;
1319 new_asoc->c.my_ttag = asoc->c.my_vtag;
1320 new_asoc->c.peer_ttag = asoc->c.peer_vtag;
1321 break;
1322
1323 /* 5.2.2 Unexpected INIT in States Other than CLOSED, COOKIE-ECHOED,
1324 * COOKIE-WAIT and SHUTDOWN-ACK-SENT
1325 */
1326 default:
1327 new_asoc->c.my_ttag = asoc->c.my_vtag;
1328 new_asoc->c.peer_ttag = asoc->c.peer_vtag;
1329 break;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07001330 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331
1332 /* Other parameters for the endpoint SHOULD be copied from the
1333 * existing parameters of the association (e.g. number of
1334 * outbound streams) into the INIT ACK and cookie.
1335 */
1336 new_asoc->rwnd = asoc->rwnd;
1337 new_asoc->c.sinit_num_ostreams = asoc->c.sinit_num_ostreams;
1338 new_asoc->c.sinit_max_instreams = asoc->c.sinit_max_instreams;
1339 new_asoc->c.initial_tsn = asoc->c.initial_tsn;
1340}
1341
1342/*
1343 * Compare vtag/tietag values to determine unexpected COOKIE-ECHO
1344 * handling action.
1345 *
1346 * RFC 2960 5.2.4 Handle a COOKIE ECHO when a TCB exists.
1347 *
1348 * Returns value representing action to be taken. These action values
1349 * correspond to Action/Description values in RFC 2960, Table 2.
1350 */
1351static char sctp_tietags_compare(struct sctp_association *new_asoc,
1352 const struct sctp_association *asoc)
1353{
1354 /* In this case, the peer may have restarted. */
1355 if ((asoc->c.my_vtag != new_asoc->c.my_vtag) &&
1356 (asoc->c.peer_vtag != new_asoc->c.peer_vtag) &&
1357 (asoc->c.my_vtag == new_asoc->c.my_ttag) &&
1358 (asoc->c.peer_vtag == new_asoc->c.peer_ttag))
1359 return 'A';
1360
1361 /* Collision case B. */
1362 if ((asoc->c.my_vtag == new_asoc->c.my_vtag) &&
1363 ((asoc->c.peer_vtag != new_asoc->c.peer_vtag) ||
1364 (0 == asoc->c.peer_vtag))) {
1365 return 'B';
1366 }
1367
1368 /* Collision case D. */
1369 if ((asoc->c.my_vtag == new_asoc->c.my_vtag) &&
1370 (asoc->c.peer_vtag == new_asoc->c.peer_vtag))
1371 return 'D';
1372
1373 /* Collision case C. */
1374 if ((asoc->c.my_vtag != new_asoc->c.my_vtag) &&
1375 (asoc->c.peer_vtag == new_asoc->c.peer_vtag) &&
1376 (0 == new_asoc->c.my_ttag) &&
1377 (0 == new_asoc->c.peer_ttag))
1378 return 'C';
1379
1380 /* No match to any of the special cases; discard this packet. */
1381 return 'E';
1382}
1383
1384/* Common helper routine for both duplicate and simulataneous INIT
1385 * chunk handling.
1386 */
1387static sctp_disposition_t sctp_sf_do_unexpected_init(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001388 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389 const struct sctp_endpoint *ep,
1390 const struct sctp_association *asoc,
1391 const sctp_subtype_t type,
1392 void *arg, sctp_cmd_seq_t *commands)
1393{
1394 sctp_disposition_t retval;
1395 struct sctp_chunk *chunk = arg;
1396 struct sctp_chunk *repl;
1397 struct sctp_association *new_asoc;
1398 struct sctp_chunk *err_chunk;
1399 struct sctp_packet *packet;
1400 sctp_unrecognized_param_t *unk_param;
1401 int len;
1402
1403 /* 6.10 Bundling
1404 * An endpoint MUST NOT bundle INIT, INIT ACK or
1405 * SHUTDOWN COMPLETE with any other chunks.
1406 *
1407 * IG Section 2.11.2
1408 * Furthermore, we require that the receiver of an INIT chunk MUST
1409 * enforce these rules by silently discarding an arriving packet
1410 * with an INIT chunk that is bundled with other chunks.
1411 */
1412 if (!chunk->singleton)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001413 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001414
1415 /* 3.1 A packet containing an INIT chunk MUST have a zero Verification
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001416 * Tag.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 */
1418 if (chunk->sctp_hdr->vtag != 0)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001419 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001420
1421 /* Make sure that the INIT chunk has a valid length.
1422 * In this case, we generate a protocol violation since we have
1423 * an association established.
1424 */
1425 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001426 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001427 commands);
1428 /* Grab the INIT header. */
1429 chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data;
1430
1431 /* Tag the variable length parameters. */
1432 chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t));
1433
1434 /* Verify the INIT chunk before processing it. */
1435 err_chunk = NULL;
Vlad Yasevichb14878c2014-04-17 17:26:50 +02001436 if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001437 (sctp_init_chunk_t *)chunk->chunk_hdr, chunk,
1438 &err_chunk)) {
1439 /* This chunk contains fatal error. It is to be discarded.
1440 * Send an ABORT, with causes if there is any.
1441 */
1442 if (err_chunk) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001443 packet = sctp_abort_pkt_new(net, ep, asoc, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001444 (__u8 *)(err_chunk->chunk_hdr) +
1445 sizeof(sctp_chunkhdr_t),
1446 ntohs(err_chunk->chunk_hdr->length) -
1447 sizeof(sctp_chunkhdr_t));
1448
1449 if (packet) {
1450 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
1451 SCTP_PACKET(packet));
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001452 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001453 retval = SCTP_DISPOSITION_CONSUME;
1454 } else {
1455 retval = SCTP_DISPOSITION_NOMEM;
1456 }
1457 goto cleanup;
1458 } else {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001459 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001460 commands);
1461 }
1462 }
1463
1464 /*
1465 * Other parameters for the endpoint SHOULD be copied from the
1466 * existing parameters of the association (e.g. number of
1467 * outbound streams) into the INIT ACK and cookie.
1468 * FIXME: We are copying parameters from the endpoint not the
1469 * association.
1470 */
1471 new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC);
1472 if (!new_asoc)
1473 goto nomem;
1474
Vlad Yasevich409b95a2009-11-10 08:57:34 +00001475 if (sctp_assoc_set_bind_addr_from_ep(new_asoc,
1476 sctp_scope(sctp_source(chunk)), GFP_ATOMIC) < 0)
1477 goto nomem;
1478
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479 /* In the outbound INIT ACK the endpoint MUST copy its current
1480 * Verification Tag and Peers Verification tag into a reserved
1481 * place (local tie-tag and per tie-tag) within the state cookie.
1482 */
Wei Yongjunde6becd2011-04-19 21:30:51 +00001483 if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk),
Linus Torvalds1da177e2005-04-16 15:20:36 -07001484 (sctp_init_chunk_t *)chunk->chunk_hdr,
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001485 GFP_ATOMIC))
1486 goto nomem;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487
1488 /* Make sure no new addresses are being added during the
1489 * restart. Do not do this check for COOKIE-WAIT state,
1490 * since there are no peer addresses to check against.
1491 * Upon return an ABORT will have been sent if needed.
1492 */
1493 if (!sctp_state(asoc, COOKIE_WAIT)) {
1494 if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk,
1495 commands)) {
1496 retval = SCTP_DISPOSITION_CONSUME;
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001497 goto nomem_retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 }
1499 }
1500
1501 sctp_tietags_populate(new_asoc, asoc);
1502
1503 /* B) "Z" shall respond immediately with an INIT ACK chunk. */
1504
1505 /* If there are errors need to be reported for unknown parameters,
1506 * make sure to reserve enough room in the INIT ACK for them.
1507 */
1508 len = 0;
1509 if (err_chunk) {
1510 len = ntohs(err_chunk->chunk_hdr->length) -
1511 sizeof(sctp_chunkhdr_t);
1512 }
1513
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514 repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len);
1515 if (!repl)
1516 goto nomem;
1517
1518 /* If there are errors need to be reported for unknown parameters,
1519 * include them in the outgoing INIT ACK as "Unrecognized parameter"
1520 * parameter.
1521 */
1522 if (err_chunk) {
1523 /* Get the "Unrecognized parameter" parameter(s) out of the
1524 * ERROR chunk generated by sctp_verify_init(). Since the
1525 * error cause code for "unknown parameter" and the
1526 * "Unrecognized parameter" type is the same, we can
1527 * construct the parameters in INIT ACK by copying the
1528 * ERROR causes over.
1529 */
1530 unk_param = (sctp_unrecognized_param_t *)
1531 ((__u8 *)(err_chunk->chunk_hdr) +
1532 sizeof(sctp_chunkhdr_t));
1533 /* Replace the cause code with the "Unrecognized parameter"
1534 * parameter type.
1535 */
1536 sctp_addto_chunk(repl, len, unk_param);
1537 }
1538
1539 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
1540 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
1541
1542 /*
1543 * Note: After sending out INIT ACK with the State Cookie parameter,
1544 * "Z" MUST NOT allocate any resources for this new association.
1545 * Otherwise, "Z" will be vulnerable to resource attacks.
1546 */
1547 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
1548 retval = SCTP_DISPOSITION_CONSUME;
1549
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001550 return retval;
1551
1552nomem:
1553 retval = SCTP_DISPOSITION_NOMEM;
1554nomem_retval:
1555 if (new_asoc)
1556 sctp_association_free(new_asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557cleanup:
1558 if (err_chunk)
1559 sctp_chunk_free(err_chunk);
1560 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561}
1562
1563/*
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001564 * Handle simultaneous INIT.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001565 * This means we started an INIT and then we got an INIT request from
1566 * our peer.
1567 *
1568 * Section: 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State (Item B)
1569 * This usually indicates an initialization collision, i.e., each
1570 * endpoint is attempting, at about the same time, to establish an
1571 * association with the other endpoint.
1572 *
1573 * Upon receipt of an INIT in the COOKIE-WAIT or COOKIE-ECHOED state, an
1574 * endpoint MUST respond with an INIT ACK using the same parameters it
1575 * sent in its original INIT chunk (including its Verification Tag,
1576 * unchanged). These original parameters are combined with those from the
1577 * newly received INIT chunk. The endpoint shall also generate a State
1578 * Cookie with the INIT ACK. The endpoint uses the parameters sent in its
1579 * INIT to calculate the State Cookie.
1580 *
1581 * After that, the endpoint MUST NOT change its state, the T1-init
1582 * timer shall be left running and the corresponding TCB MUST NOT be
1583 * destroyed. The normal procedures for handling State Cookies when
1584 * a TCB exists will resolve the duplicate INITs to a single association.
1585 *
1586 * For an endpoint that is in the COOKIE-ECHOED state it MUST populate
1587 * its Tie-Tags with the Tag information of itself and its peer (see
1588 * section 5.2.2 for a description of the Tie-Tags).
1589 *
1590 * Verification Tag: Not explicit, but an INIT can not have a valid
1591 * verification tag, so we skip the check.
1592 *
1593 * Inputs
1594 * (endpoint, asoc, chunk)
1595 *
1596 * Outputs
1597 * (asoc, reply_msg, msg_up, timers, counters)
1598 *
1599 * The return value is the disposition of the chunk.
1600 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001601sctp_disposition_t sctp_sf_do_5_2_1_siminit(struct net *net,
1602 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001603 const struct sctp_association *asoc,
1604 const sctp_subtype_t type,
1605 void *arg,
1606 sctp_cmd_seq_t *commands)
1607{
1608 /* Call helper to do the real work for both simulataneous and
1609 * duplicate INIT chunk handling.
1610 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001611 return sctp_sf_do_unexpected_init(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612}
1613
1614/*
1615 * Handle duplicated INIT messages. These are usually delayed
1616 * restransmissions.
1617 *
1618 * Section: 5.2.2 Unexpected INIT in States Other than CLOSED,
1619 * COOKIE-ECHOED and COOKIE-WAIT
1620 *
1621 * Unless otherwise stated, upon reception of an unexpected INIT for
1622 * this association, the endpoint shall generate an INIT ACK with a
1623 * State Cookie. In the outbound INIT ACK the endpoint MUST copy its
1624 * current Verification Tag and peer's Verification Tag into a reserved
1625 * place within the state cookie. We shall refer to these locations as
1626 * the Peer's-Tie-Tag and the Local-Tie-Tag. The outbound SCTP packet
1627 * containing this INIT ACK MUST carry a Verification Tag value equal to
1628 * the Initiation Tag found in the unexpected INIT. And the INIT ACK
1629 * MUST contain a new Initiation Tag (randomly generated see Section
1630 * 5.3.1). Other parameters for the endpoint SHOULD be copied from the
1631 * existing parameters of the association (e.g. number of outbound
1632 * streams) into the INIT ACK and cookie.
1633 *
1634 * After sending out the INIT ACK, the endpoint shall take no further
1635 * actions, i.e., the existing association, including its current state,
1636 * and the corresponding TCB MUST NOT be changed.
1637 *
1638 * Note: Only when a TCB exists and the association is not in a COOKIE-
1639 * WAIT state are the Tie-Tags populated. For a normal association INIT
1640 * (i.e. the endpoint is in a COOKIE-WAIT state), the Tie-Tags MUST be
1641 * set to 0 (indicating that no previous TCB existed). The INIT ACK and
1642 * State Cookie are populated as specified in section 5.2.1.
1643 *
1644 * Verification Tag: Not specified, but an INIT has no way of knowing
1645 * what the verification tag could be, so we ignore it.
1646 *
1647 * Inputs
1648 * (endpoint, asoc, chunk)
1649 *
1650 * Outputs
1651 * (asoc, reply_msg, msg_up, timers, counters)
1652 *
1653 * The return value is the disposition of the chunk.
1654 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001655sctp_disposition_t sctp_sf_do_5_2_2_dupinit(struct net *net,
1656 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 const struct sctp_association *asoc,
1658 const sctp_subtype_t type,
1659 void *arg,
1660 sctp_cmd_seq_t *commands)
1661{
1662 /* Call helper to do the real work for both simulataneous and
1663 * duplicate INIT chunk handling.
1664 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001665 return sctp_sf_do_unexpected_init(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666}
1667
1668
Vlad Yasevich610ab732007-01-15 19:18:30 -08001669/*
1670 * Unexpected INIT-ACK handler.
1671 *
1672 * Section 5.2.3
1673 * If an INIT ACK received by an endpoint in any state other than the
1674 * COOKIE-WAIT state, the endpoint should discard the INIT ACK chunk.
1675 * An unexpected INIT ACK usually indicates the processing of an old or
1676 * duplicated INIT chunk.
1677*/
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001678sctp_disposition_t sctp_sf_do_5_2_3_initack(struct net *net,
1679 const struct sctp_endpoint *ep,
Vlad Yasevich610ab732007-01-15 19:18:30 -08001680 const struct sctp_association *asoc,
1681 const sctp_subtype_t type,
1682 void *arg, sctp_cmd_seq_t *commands)
1683{
1684 /* Per the above section, we'll discard the chunk if we have an
1685 * endpoint. If this is an OOTB INIT-ACK, treat it as such.
1686 */
Eric W. Biederman2ce95502012-08-06 08:43:06 +00001687 if (ep == sctp_sk(net->sctp.ctl_sock)->ep)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001688 return sctp_sf_ootb(net, ep, asoc, type, arg, commands);
Vlad Yasevich610ab732007-01-15 19:18:30 -08001689 else
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001690 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich610ab732007-01-15 19:18:30 -08001691}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001692
1693/* Unexpected COOKIE-ECHO handler for peer restart (Table 2, action 'A')
1694 *
1695 * Section 5.2.4
1696 * A) In this case, the peer may have restarted.
1697 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001698static sctp_disposition_t sctp_sf_do_dupcook_a(struct net *net,
1699 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001700 const struct sctp_association *asoc,
1701 struct sctp_chunk *chunk,
1702 sctp_cmd_seq_t *commands,
1703 struct sctp_association *new_asoc)
1704{
1705 sctp_init_chunk_t *peer_init;
1706 struct sctp_ulpevent *ev;
1707 struct sctp_chunk *repl;
1708 struct sctp_chunk *err;
1709 sctp_disposition_t disposition;
1710
1711 /* new_asoc is a brand-new association, so these are not yet
1712 * side effects--it is safe to run them here.
1713 */
1714 peer_init = &chunk->subh.cookie_hdr->c.peer_init[0];
1715
Wei Yongjunde6becd2011-04-19 21:30:51 +00001716 if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001717 GFP_ATOMIC))
1718 goto nomem;
1719
1720 /* Make sure no new addresses are being added during the
1721 * restart. Though this is a pretty complicated attack
1722 * since you'd have to get inside the cookie.
1723 */
1724 if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) {
1725 return SCTP_DISPOSITION_CONSUME;
1726 }
1727
1728 /* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes
1729 * the peer has restarted (Action A), it MUST NOT setup a new
1730 * association but instead resend the SHUTDOWN ACK and send an ERROR
1731 * chunk with a "Cookie Received while Shutting Down" error cause to
1732 * its peer.
1733 */
1734 if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001735 disposition = sctp_sf_do_9_2_reshutack(net, ep, asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001736 SCTP_ST_CHUNK(chunk->chunk_hdr->type),
1737 chunk, commands);
1738 if (SCTP_DISPOSITION_NOMEM == disposition)
1739 goto nomem;
1740
1741 err = sctp_make_op_error(asoc, chunk,
1742 SCTP_ERROR_COOKIE_IN_SHUTDOWN,
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05001743 NULL, 0, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001744 if (err)
1745 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1746 SCTP_CHUNK(err));
1747
1748 return SCTP_DISPOSITION_CONSUME;
1749 }
1750
Wei Yongjuna000c012011-05-29 23:23:36 +00001751 /* For now, stop pending T3-rtx and SACK timers, fail any unsent/unacked
1752 * data. Consider the optional choice of resending of this data.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001753 */
Wei Yongjuna000c012011-05-29 23:23:36 +00001754 sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL());
1755 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
1756 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001757 sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL());
1758
Wei Yongjuna000c012011-05-29 23:23:36 +00001759 /* Stop pending T4-rto timer, teardown ASCONF queue, ASCONF-ACK queue
1760 * and ASCONF-ACK cache.
1761 */
1762 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
1763 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
1764 sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_ASCONF_QUEUE, SCTP_NULL());
1765
Linus Torvalds1da177e2005-04-16 15:20:36 -07001766 repl = sctp_make_cookie_ack(new_asoc, chunk);
1767 if (!repl)
1768 goto nomem;
1769
Linus Torvalds1da177e2005-04-16 15:20:36 -07001770 /* Report association restart to upper layer. */
1771 ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0,
1772 new_asoc->c.sinit_num_ostreams,
1773 new_asoc->c.sinit_max_instreams,
Vlad Yasevicha5a35e72007-03-23 11:34:08 -07001774 NULL, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001775 if (!ev)
1776 goto nomem_ev;
1777
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001778 /* Update the content of current association. */
1779 sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001780 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
Vlad Yasevichbdf6fa52014-10-03 18:16:20 -04001781 if (sctp_state(asoc, SHUTDOWN_PENDING) &&
1782 (sctp_sstate(asoc->base.sk, CLOSING) ||
1783 sock_flag(asoc->base.sk, SOCK_DEAD))) {
1784 /* if were currently in SHUTDOWN_PENDING, but the socket
1785 * has been closed by user, don't transition to ESTABLISHED.
1786 * Instead trigger SHUTDOWN bundled with COOKIE_ACK.
1787 */
1788 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
1789 return sctp_sf_do_9_2_start_shutdown(net, ep, asoc,
1790 SCTP_ST_CHUNK(0), NULL,
1791 commands);
1792 } else {
1793 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
1794 SCTP_STATE(SCTP_STATE_ESTABLISHED));
1795 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
1796 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001797 return SCTP_DISPOSITION_CONSUME;
1798
1799nomem_ev:
1800 sctp_chunk_free(repl);
1801nomem:
1802 return SCTP_DISPOSITION_NOMEM;
1803}
1804
1805/* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'B')
1806 *
1807 * Section 5.2.4
1808 * B) In this case, both sides may be attempting to start an association
1809 * at about the same time but the peer endpoint started its INIT
1810 * after responding to the local endpoint's INIT
1811 */
1812/* This case represents an initialization collision. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001813static sctp_disposition_t sctp_sf_do_dupcook_b(struct net *net,
1814 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001815 const struct sctp_association *asoc,
1816 struct sctp_chunk *chunk,
1817 sctp_cmd_seq_t *commands,
1818 struct sctp_association *new_asoc)
1819{
1820 sctp_init_chunk_t *peer_init;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001821 struct sctp_chunk *repl;
1822
1823 /* new_asoc is a brand-new association, so these are not yet
1824 * side effects--it is safe to run them here.
1825 */
1826 peer_init = &chunk->subh.cookie_hdr->c.peer_init[0];
Wei Yongjunde6becd2011-04-19 21:30:51 +00001827 if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001828 GFP_ATOMIC))
1829 goto nomem;
1830
1831 /* Update the content of current association. */
1832 sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc));
1833 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
1834 SCTP_STATE(SCTP_STATE_ESTABLISHED));
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001835 SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001836 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL());
1837
1838 repl = sctp_make_cookie_ack(new_asoc, chunk);
1839 if (!repl)
1840 goto nomem;
1841
1842 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001843
1844 /* RFC 2960 5.1 Normal Establishment of an Association
1845 *
1846 * D) IMPLEMENTATION NOTE: An implementation may choose to
1847 * send the Communication Up notification to the SCTP user
1848 * upon reception of a valid COOKIE ECHO chunk.
Vlad Yasevich07d93962007-05-04 13:55:27 -07001849 *
1850 * Sadly, this needs to be implemented as a side-effect, because
1851 * we are not guaranteed to have set the association id of the real
1852 * association and so these notifications need to be delayed until
1853 * the association id is allocated.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001854 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001855
Vlad Yasevich07d93962007-05-04 13:55:27 -07001856 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_CHANGE, SCTP_U8(SCTP_COMM_UP));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001857
1858 /* Sockets API Draft Section 5.3.1.6
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -08001859 * When a peer sends a Adaptation Layer Indication parameter , SCTP
Linus Torvalds1da177e2005-04-16 15:20:36 -07001860 * delivers this notification to inform the application that of the
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -08001861 * peers requested adaptation layer.
Vlad Yasevich07d93962007-05-04 13:55:27 -07001862 *
1863 * This also needs to be done as a side effect for the same reason as
1864 * above.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001865 */
Vlad Yasevich07d93962007-05-04 13:55:27 -07001866 if (asoc->peer.adaptation_ind)
1867 sctp_add_cmd_sf(commands, SCTP_CMD_ADAPTATION_IND, SCTP_NULL());
Linus Torvalds1da177e2005-04-16 15:20:36 -07001868
1869 return SCTP_DISPOSITION_CONSUME;
1870
Linus Torvalds1da177e2005-04-16 15:20:36 -07001871nomem:
1872 return SCTP_DISPOSITION_NOMEM;
1873}
1874
1875/* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'C')
1876 *
1877 * Section 5.2.4
1878 * C) In this case, the local endpoint's cookie has arrived late.
1879 * Before it arrived, the local endpoint sent an INIT and received an
1880 * INIT-ACK and finally sent a COOKIE ECHO with the peer's same tag
1881 * but a new tag of its own.
1882 */
1883/* This case represents an initialization collision. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001884static sctp_disposition_t sctp_sf_do_dupcook_c(struct net *net,
1885 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001886 const struct sctp_association *asoc,
1887 struct sctp_chunk *chunk,
1888 sctp_cmd_seq_t *commands,
1889 struct sctp_association *new_asoc)
1890{
1891 /* The cookie should be silently discarded.
1892 * The endpoint SHOULD NOT change states and should leave
1893 * any timers running.
1894 */
1895 return SCTP_DISPOSITION_DISCARD;
1896}
1897
1898/* Unexpected COOKIE-ECHO handler lost chunk (Table 2, action 'D')
1899 *
1900 * Section 5.2.4
1901 *
1902 * D) When both local and remote tags match the endpoint should always
1903 * enter the ESTABLISHED state, if it has not already done so.
1904 */
1905/* This case represents an initialization collision. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001906static sctp_disposition_t sctp_sf_do_dupcook_d(struct net *net,
1907 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001908 const struct sctp_association *asoc,
1909 struct sctp_chunk *chunk,
1910 sctp_cmd_seq_t *commands,
1911 struct sctp_association *new_asoc)
1912{
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001913 struct sctp_ulpevent *ev = NULL, *ai_ev = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001914 struct sctp_chunk *repl;
1915
1916 /* Clarification from Implementor's Guide:
1917 * D) When both local and remote tags match the endpoint should
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001918 * enter the ESTABLISHED state, if it is in the COOKIE-ECHOED state.
1919 * It should stop any cookie timer that may be running and send
1920 * a COOKIE ACK.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001921 */
1922
1923 /* Don't accidentally move back into established state. */
1924 if (asoc->state < SCTP_STATE_ESTABLISHED) {
1925 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
1926 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1927 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
1928 SCTP_STATE(SCTP_STATE_ESTABLISHED));
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00001929 SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001930 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START,
1931 SCTP_NULL());
1932
1933 /* RFC 2960 5.1 Normal Establishment of an Association
1934 *
1935 * D) IMPLEMENTATION NOTE: An implementation may choose
1936 * to send the Communication Up notification to the
1937 * SCTP user upon reception of a valid COOKIE
1938 * ECHO chunk.
1939 */
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001940 ev = sctp_ulpevent_make_assoc_change(asoc, 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001941 SCTP_COMM_UP, 0,
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001942 asoc->c.sinit_num_ostreams,
1943 asoc->c.sinit_max_instreams,
YOSHIFUJI Hideaki9cbcbf42007-07-19 10:44:50 +09001944 NULL, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001945 if (!ev)
1946 goto nomem;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001947
1948 /* Sockets API Draft Section 5.3.1.6
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -08001949 * When a peer sends a Adaptation Layer Indication parameter,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001950 * SCTP delivers this notification to inform the application
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -08001951 * that of the peers requested adaptation layer.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001952 */
Ivan Skytte Jorgensen0f3fffd2006-12-20 16:07:04 -08001953 if (asoc->peer.adaptation_ind) {
1954 ai_ev = sctp_ulpevent_make_adaptation_indication(asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001955 GFP_ATOMIC);
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001956 if (!ai_ev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001957 goto nomem;
1958
Linus Torvalds1da177e2005-04-16 15:20:36 -07001959 }
1960 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001961
1962 repl = sctp_make_cookie_ack(new_asoc, chunk);
1963 if (!repl)
1964 goto nomem;
1965
Vlad Yasevich2e3216c2008-06-19 16:08:18 -07001966 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
1967
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001968 if (ev)
1969 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
1970 SCTP_ULPEVENT(ev));
1971 if (ai_ev)
1972 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
1973 SCTP_ULPEVENT(ai_ev));
1974
Linus Torvalds1da177e2005-04-16 15:20:36 -07001975 return SCTP_DISPOSITION_CONSUME;
1976
1977nomem:
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07001978 if (ai_ev)
1979 sctp_ulpevent_free(ai_ev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001980 if (ev)
1981 sctp_ulpevent_free(ev);
1982 return SCTP_DISPOSITION_NOMEM;
1983}
1984
1985/*
1986 * Handle a duplicate COOKIE-ECHO. This usually means a cookie-carrying
1987 * chunk was retransmitted and then delayed in the network.
1988 *
1989 * Section: 5.2.4 Handle a COOKIE ECHO when a TCB exists
1990 *
1991 * Verification Tag: None. Do cookie validation.
1992 *
1993 * Inputs
1994 * (endpoint, asoc, chunk)
1995 *
1996 * Outputs
1997 * (asoc, reply_msg, msg_up, timers, counters)
1998 *
1999 * The return value is the disposition of the chunk.
2000 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002001sctp_disposition_t sctp_sf_do_5_2_4_dupcook(struct net *net,
2002 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002003 const struct sctp_association *asoc,
2004 const sctp_subtype_t type,
2005 void *arg,
2006 sctp_cmd_seq_t *commands)
2007{
2008 sctp_disposition_t retval;
2009 struct sctp_chunk *chunk = arg;
2010 struct sctp_association *new_asoc;
2011 int error = 0;
2012 char action;
2013 struct sctp_chunk *err_chk_p;
2014
2015 /* Make sure that the chunk has a valid length from the protocol
2016 * perspective. In this case check to make sure we have at least
2017 * enough for the chunk header. Cookie length verification is
2018 * done later.
2019 */
2020 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002021 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002022 commands);
2023
2024 /* "Decode" the chunk. We have no optional parameters so we
2025 * are in good shape.
2026 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09002027 chunk->subh.cookie_hdr = (struct sctp_signed_cookie *)chunk->skb->data;
Sridhar Samudrala62b08082006-05-05 17:04:43 -07002028 if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) -
2029 sizeof(sctp_chunkhdr_t)))
2030 goto nomem;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002031
2032 /* In RFC 2960 5.2.4 3, if both Verification Tags in the State Cookie
2033 * of a duplicate COOKIE ECHO match the Verification Tags of the
2034 * current association, consider the State Cookie valid even if
2035 * the lifespan is exceeded.
2036 */
2037 new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error,
2038 &err_chk_p);
2039
2040 /* FIXME:
2041 * If the re-build failed, what is the proper error path
2042 * from here?
2043 *
2044 * [We should abort the association. --piggy]
2045 */
2046 if (!new_asoc) {
2047 /* FIXME: Several errors are possible. A bad cookie should
2048 * be silently discarded, but think about logging it too.
2049 */
2050 switch (error) {
2051 case -SCTP_IERROR_NOMEM:
2052 goto nomem;
2053
2054 case -SCTP_IERROR_STALE_COOKIE:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002055 sctp_send_stale_cookie_err(net, ep, asoc, chunk, commands,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002056 err_chk_p);
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002057 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002058 case -SCTP_IERROR_BAD_SIG:
2059 default:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002060 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07002061 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002062 }
2063
2064 /* Compare the tie_tag in cookie with the verification tag of
2065 * current association.
2066 */
2067 action = sctp_tietags_compare(new_asoc, asoc);
2068
2069 switch (action) {
2070 case 'A': /* Association restart. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002071 retval = sctp_sf_do_dupcook_a(net, ep, asoc, chunk, commands,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002072 new_asoc);
2073 break;
2074
2075 case 'B': /* Collision case B. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002076 retval = sctp_sf_do_dupcook_b(net, ep, asoc, chunk, commands,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002077 new_asoc);
2078 break;
2079
2080 case 'C': /* Collision case C. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002081 retval = sctp_sf_do_dupcook_c(net, ep, asoc, chunk, commands,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002082 new_asoc);
2083 break;
2084
2085 case 'D': /* Collision case D. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002086 retval = sctp_sf_do_dupcook_d(net, ep, asoc, chunk, commands,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002087 new_asoc);
2088 break;
2089
2090 default: /* Discard packet for all others. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002091 retval = sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002092 break;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07002093 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002094
2095 /* Delete the tempory new association. */
Vlad Yasevichf2815632013-03-12 15:53:23 +00002096 sctp_add_cmd_sf(commands, SCTP_CMD_SET_ASOC, SCTP_ASOC(new_asoc));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002097 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
2098
Max Matveevd5ccd492011-08-29 21:02:24 +00002099 /* Restore association pointer to provide SCTP command interpeter
2100 * with a valid context in case it needs to manipulate
2101 * the queues */
2102 sctp_add_cmd_sf(commands, SCTP_CMD_SET_ASOC,
2103 SCTP_ASOC((struct sctp_association *)asoc));
2104
Linus Torvalds1da177e2005-04-16 15:20:36 -07002105 return retval;
2106
2107nomem:
2108 return SCTP_DISPOSITION_NOMEM;
2109}
2110
2111/*
2112 * Process an ABORT. (SHUTDOWN-PENDING state)
2113 *
2114 * See sctp_sf_do_9_1_abort().
2115 */
2116sctp_disposition_t sctp_sf_shutdown_pending_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002117 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002118 const struct sctp_endpoint *ep,
2119 const struct sctp_association *asoc,
2120 const sctp_subtype_t type,
2121 void *arg,
2122 sctp_cmd_seq_t *commands)
2123{
2124 struct sctp_chunk *chunk = arg;
2125
2126 if (!sctp_vtag_verify_either(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002127 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002128
2129 /* Make sure that the ABORT chunk has a valid length.
2130 * Since this is an ABORT chunk, we have to discard it
2131 * because of the following text:
2132 * RFC 2960, Section 3.3.7
2133 * If an endpoint receives an ABORT with a format error or for an
2134 * association that doesn't exist, it MUST silently discard it.
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002135 * Because the length is "invalid", we can't really discard just
Linus Torvalds1da177e2005-04-16 15:20:36 -07002136 * as we do not know its true length. So, to be safe, discard the
2137 * packet.
2138 */
2139 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002140 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002141
Vlad Yasevich75205f42007-12-20 14:12:59 -08002142 /* ADD-IP: Special case for ABORT chunks
2143 * F4) One special consideration is that ABORT Chunks arriving
2144 * destined to the IP address being deleted MUST be
2145 * ignored (see Section 5.3.1 for further details).
2146 */
2147 if (SCTP_ADDR_DEL ==
2148 sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002149 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich75205f42007-12-20 14:12:59 -08002150
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002151 return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002152}
2153
2154/*
2155 * Process an ABORT. (SHUTDOWN-SENT state)
2156 *
2157 * See sctp_sf_do_9_1_abort().
2158 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002159sctp_disposition_t sctp_sf_shutdown_sent_abort(struct net *net,
2160 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002161 const struct sctp_association *asoc,
2162 const sctp_subtype_t type,
2163 void *arg,
2164 sctp_cmd_seq_t *commands)
2165{
2166 struct sctp_chunk *chunk = arg;
2167
2168 if (!sctp_vtag_verify_either(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002169 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002170
2171 /* Make sure that the ABORT chunk has a valid length.
2172 * Since this is an ABORT chunk, we have to discard it
2173 * because of the following text:
2174 * RFC 2960, Section 3.3.7
2175 * If an endpoint receives an ABORT with a format error or for an
2176 * association that doesn't exist, it MUST silently discard it.
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002177 * Because the length is "invalid", we can't really discard just
Linus Torvalds1da177e2005-04-16 15:20:36 -07002178 * as we do not know its true length. So, to be safe, discard the
2179 * packet.
2180 */
2181 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002182 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002183
Vlad Yasevich75205f42007-12-20 14:12:59 -08002184 /* ADD-IP: Special case for ABORT chunks
2185 * F4) One special consideration is that ABORT Chunks arriving
2186 * destined to the IP address being deleted MUST be
2187 * ignored (see Section 5.3.1 for further details).
2188 */
2189 if (SCTP_ADDR_DEL ==
2190 sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002191 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich75205f42007-12-20 14:12:59 -08002192
Linus Torvalds1da177e2005-04-16 15:20:36 -07002193 /* Stop the T2-shutdown timer. */
2194 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
2195 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
2196
2197 /* Stop the T5-shutdown guard timer. */
2198 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
2199 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
2200
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002201 return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002202}
2203
2204/*
2205 * Process an ABORT. (SHUTDOWN-ACK-SENT state)
2206 *
2207 * See sctp_sf_do_9_1_abort().
2208 */
2209sctp_disposition_t sctp_sf_shutdown_ack_sent_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002210 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002211 const struct sctp_endpoint *ep,
2212 const struct sctp_association *asoc,
2213 const sctp_subtype_t type,
2214 void *arg,
2215 sctp_cmd_seq_t *commands)
2216{
2217 /* The same T2 timer, so we should be able to use
2218 * common function with the SHUTDOWN-SENT state.
2219 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002220 return sctp_sf_shutdown_sent_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002221}
2222
2223/*
2224 * Handle an Error received in COOKIE_ECHOED state.
2225 *
2226 * Only handle the error type of stale COOKIE Error, the other errors will
2227 * be ignored.
2228 *
2229 * Inputs
2230 * (endpoint, asoc, chunk)
2231 *
2232 * Outputs
2233 * (asoc, reply_msg, msg_up, timers, counters)
2234 *
2235 * The return value is the disposition of the chunk.
2236 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002237sctp_disposition_t sctp_sf_cookie_echoed_err(struct net *net,
2238 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002239 const struct sctp_association *asoc,
2240 const sctp_subtype_t type,
2241 void *arg,
2242 sctp_cmd_seq_t *commands)
2243{
2244 struct sctp_chunk *chunk = arg;
2245 sctp_errhdr_t *err;
2246
2247 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002248 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002249
2250 /* Make sure that the ERROR chunk has a valid length.
2251 * The parameter walking depends on this as well.
2252 */
2253 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002254 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002255 commands);
2256
2257 /* Process the error here */
2258 /* FUTURE FIXME: When PR-SCTP related and other optional
2259 * parms are emitted, this will have to change to handle multiple
2260 * errors.
2261 */
2262 sctp_walk_errors(err, chunk->chunk_hdr) {
2263 if (SCTP_ERROR_STALE_COOKIE == err->cause)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002264 return sctp_sf_do_5_2_6_stale(net, ep, asoc, type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002265 arg, commands);
2266 }
2267
2268 /* It is possible to have malformed error causes, and that
2269 * will cause us to end the walk early. However, since
2270 * we are discarding the packet, there should be no adverse
2271 * affects.
2272 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002273 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002274}
2275
2276/*
2277 * Handle a Stale COOKIE Error
2278 *
2279 * Section: 5.2.6 Handle Stale COOKIE Error
2280 * If the association is in the COOKIE-ECHOED state, the endpoint may elect
2281 * one of the following three alternatives.
2282 * ...
2283 * 3) Send a new INIT chunk to the endpoint, adding a Cookie
2284 * Preservative parameter requesting an extension to the lifetime of
2285 * the State Cookie. When calculating the time extension, an
2286 * implementation SHOULD use the RTT information measured based on the
2287 * previous COOKIE ECHO / ERROR exchange, and should add no more
2288 * than 1 second beyond the measured RTT, due to long State Cookie
2289 * lifetimes making the endpoint more subject to a replay attack.
2290 *
2291 * Verification Tag: Not explicit, but safe to ignore.
2292 *
2293 * Inputs
2294 * (endpoint, asoc, chunk)
2295 *
2296 * Outputs
2297 * (asoc, reply_msg, msg_up, timers, counters)
2298 *
2299 * The return value is the disposition of the chunk.
2300 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002301static sctp_disposition_t sctp_sf_do_5_2_6_stale(struct net *net,
2302 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002303 const struct sctp_association *asoc,
2304 const sctp_subtype_t type,
2305 void *arg,
2306 sctp_cmd_seq_t *commands)
2307{
2308 struct sctp_chunk *chunk = arg;
Arnd Bergmann3ef0a252015-09-30 13:26:40 +02002309 u32 stale;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002310 sctp_cookie_preserve_param_t bht;
2311 sctp_errhdr_t *err;
2312 struct sctp_chunk *reply;
2313 struct sctp_bind_addr *bp;
Frank Filz3f7a87d2005-06-20 13:14:57 -07002314 int attempts = asoc->init_err_counter + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002315
Vlad Yasevich81845c22006-01-30 15:59:54 -08002316 if (attempts > asoc->max_init_attempts) {
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07002317 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
2318 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002319 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08002320 SCTP_PERR(SCTP_ERROR_STALE_COOKIE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002321 return SCTP_DISPOSITION_DELETE_TCB;
2322 }
2323
2324 err = (sctp_errhdr_t *)(chunk->skb->data);
2325
2326 /* When calculating the time extension, an implementation
2327 * SHOULD use the RTT information measured based on the
2328 * previous COOKIE ECHO / ERROR exchange, and should add no
2329 * more than 1 second beyond the measured RTT, due to long
2330 * State Cookie lifetimes making the endpoint more subject to
2331 * a replay attack.
2332 * Measure of Staleness's unit is usec. (1/1000000 sec)
2333 * Suggested Cookie Life-span Increment's unit is msec.
2334 * (1/1000 sec)
2335 * In general, if you use the suggested cookie life, the value
2336 * found in the field of measure of staleness should be doubled
2337 * to give ample time to retransmit the new cookie and thus
2338 * yield a higher probability of success on the reattempt.
2339 */
Al Viro34bcca22006-11-20 17:27:15 -08002340 stale = ntohl(*(__be32 *)((u8 *)err + sizeof(sctp_errhdr_t)));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002341 stale = (stale * 2) / 1000;
2342
2343 bht.param_hdr.type = SCTP_PARAM_COOKIE_PRESERVATIVE;
2344 bht.param_hdr.length = htons(sizeof(bht));
2345 bht.lifespan_increment = htonl(stale);
2346
2347 /* Build that new INIT chunk. */
2348 bp = (struct sctp_bind_addr *) &asoc->base.bind_addr;
2349 reply = sctp_make_init(asoc, bp, GFP_ATOMIC, sizeof(bht));
2350 if (!reply)
2351 goto nomem;
2352
2353 sctp_addto_chunk(reply, sizeof(bht), &bht);
2354
2355 /* Clear peer's init_tag cached in assoc as we are sending a new INIT */
2356 sctp_add_cmd_sf(commands, SCTP_CMD_CLEAR_INIT_TAG, SCTP_NULL());
2357
2358 /* Stop pending T3-rtx and heartbeat timers */
2359 sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL());
2360 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL());
2361
2362 /* Delete non-primary peer ip addresses since we are transitioning
2363 * back to the COOKIE-WAIT state
2364 */
2365 sctp_add_cmd_sf(commands, SCTP_CMD_DEL_NON_PRIMARY, SCTP_NULL());
2366
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09002367 /* If we've sent any data bundled with COOKIE-ECHO we will need to
2368 * resend
Linus Torvalds1da177e2005-04-16 15:20:36 -07002369 */
Vlad Yasevichb6157d82007-10-24 15:59:16 -04002370 sctp_add_cmd_sf(commands, SCTP_CMD_T1_RETRAN,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002371 SCTP_TRANSPORT(asoc->peer.primary_path));
2372
2373 /* Cast away the const modifier, as we want to just
2374 * rerun it through as a sideffect.
2375 */
Frank Filz3f7a87d2005-06-20 13:14:57 -07002376 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_INC, SCTP_NULL());
Linus Torvalds1da177e2005-04-16 15:20:36 -07002377
2378 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
2379 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
2380 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
2381 SCTP_STATE(SCTP_STATE_COOKIE_WAIT));
2382 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
2383 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
2384
2385 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
2386
2387 return SCTP_DISPOSITION_CONSUME;
2388
2389nomem:
2390 return SCTP_DISPOSITION_NOMEM;
2391}
2392
2393/*
2394 * Process an ABORT.
2395 *
2396 * Section: 9.1
2397 * After checking the Verification Tag, the receiving endpoint shall
2398 * remove the association from its record, and shall report the
2399 * termination to its upper layer.
2400 *
2401 * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules
2402 * B) Rules for packet carrying ABORT:
2403 *
2404 * - The endpoint shall always fill in the Verification Tag field of the
2405 * outbound packet with the destination endpoint's tag value if it
2406 * is known.
2407 *
2408 * - If the ABORT is sent in response to an OOTB packet, the endpoint
2409 * MUST follow the procedure described in Section 8.4.
2410 *
2411 * - The receiver MUST accept the packet if the Verification Tag
2412 * matches either its own tag, OR the tag of its peer. Otherwise, the
2413 * receiver MUST silently discard the packet and take no further
2414 * action.
2415 *
2416 * Inputs
2417 * (endpoint, asoc, chunk)
2418 *
2419 * Outputs
2420 * (asoc, reply_msg, msg_up, timers, counters)
2421 *
2422 * The return value is the disposition of the chunk.
2423 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002424sctp_disposition_t sctp_sf_do_9_1_abort(struct net *net,
2425 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002426 const struct sctp_association *asoc,
2427 const sctp_subtype_t type,
2428 void *arg,
2429 sctp_cmd_seq_t *commands)
2430{
2431 struct sctp_chunk *chunk = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002432
2433 if (!sctp_vtag_verify_either(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002434 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002435
2436 /* Make sure that the ABORT chunk has a valid length.
2437 * Since this is an ABORT chunk, we have to discard it
2438 * because of the following text:
2439 * RFC 2960, Section 3.3.7
2440 * If an endpoint receives an ABORT with a format error or for an
2441 * association that doesn't exist, it MUST silently discard it.
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002442 * Because the length is "invalid", we can't really discard just
Linus Torvalds1da177e2005-04-16 15:20:36 -07002443 * as we do not know its true length. So, to be safe, discard the
2444 * packet.
2445 */
2446 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002447 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002448
Vlad Yasevich75205f42007-12-20 14:12:59 -08002449 /* ADD-IP: Special case for ABORT chunks
2450 * F4) One special consideration is that ABORT Chunks arriving
2451 * destined to the IP address being deleted MUST be
2452 * ignored (see Section 5.3.1 for further details).
2453 */
2454 if (SCTP_ADDR_DEL ==
2455 sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002456 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich75205f42007-12-20 14:12:59 -08002457
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002458 return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands);
Vlad Yasevich75205f42007-12-20 14:12:59 -08002459}
2460
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002461static sctp_disposition_t __sctp_sf_do_9_1_abort(struct net *net,
2462 const struct sctp_endpoint *ep,
Vlad Yasevich75205f42007-12-20 14:12:59 -08002463 const struct sctp_association *asoc,
2464 const sctp_subtype_t type,
2465 void *arg,
2466 sctp_cmd_seq_t *commands)
2467{
2468 struct sctp_chunk *chunk = arg;
Eric Dumazet95c96172012-04-15 05:58:06 +00002469 unsigned int len;
Vlad Yasevich75205f42007-12-20 14:12:59 -08002470 __be16 error = SCTP_ERROR_NO_ERROR;
2471
Linus Torvalds1da177e2005-04-16 15:20:36 -07002472 /* See if we have an error cause code in the chunk. */
2473 len = ntohs(chunk->chunk_hdr->length);
Shan Wei96ca4682011-04-19 21:26:26 +00002474 if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) {
2475
2476 sctp_errhdr_t *err;
2477 sctp_walk_errors(err, chunk->chunk_hdr);
2478 if ((void *)err != (void *)chunk->chunk_end)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002479 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Shan Wei96ca4682011-04-19 21:26:26 +00002480
Linus Torvalds1da177e2005-04-16 15:20:36 -07002481 error = ((sctp_errhdr_t *)chunk->skb->data)->cause;
Shan Wei96ca4682011-04-19 21:26:26 +00002482 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002483
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07002484 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET));
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09002485 /* ASSOC_FAILED will DELETE_TCB. */
Al Viro5be291f2006-11-20 17:01:06 -08002486 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_PERR(error));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00002487 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
2488 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002489
2490 return SCTP_DISPOSITION_ABORT;
2491}
2492
2493/*
2494 * Process an ABORT. (COOKIE-WAIT state)
2495 *
2496 * See sctp_sf_do_9_1_abort() above.
2497 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002498sctp_disposition_t sctp_sf_cookie_wait_abort(struct net *net,
2499 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002500 const struct sctp_association *asoc,
2501 const sctp_subtype_t type,
2502 void *arg,
2503 sctp_cmd_seq_t *commands)
2504{
2505 struct sctp_chunk *chunk = arg;
Eric Dumazet95c96172012-04-15 05:58:06 +00002506 unsigned int len;
Al Virof94c0192006-11-20 17:00:25 -08002507 __be16 error = SCTP_ERROR_NO_ERROR;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002508
2509 if (!sctp_vtag_verify_either(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002510 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002511
2512 /* Make sure that the ABORT chunk has a valid length.
2513 * Since this is an ABORT chunk, we have to discard it
2514 * because of the following text:
2515 * RFC 2960, Section 3.3.7
2516 * If an endpoint receives an ABORT with a format error or for an
2517 * association that doesn't exist, it MUST silently discard it.
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002518 * Because the length is "invalid", we can't really discard just
Linus Torvalds1da177e2005-04-16 15:20:36 -07002519 * as we do not know its true length. So, to be safe, discard the
2520 * packet.
2521 */
2522 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002523 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002524
2525 /* See if we have an error cause code in the chunk. */
2526 len = ntohs(chunk->chunk_hdr->length);
2527 if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr))
2528 error = ((sctp_errhdr_t *)chunk->skb->data)->cause;
2529
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002530 return sctp_stop_t1_and_abort(net, commands, error, ECONNREFUSED, asoc,
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07002531 chunk->transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002532}
2533
2534/*
2535 * Process an incoming ICMP as an ABORT. (COOKIE-WAIT state)
2536 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002537sctp_disposition_t sctp_sf_cookie_wait_icmp_abort(struct net *net,
2538 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002539 const struct sctp_association *asoc,
2540 const sctp_subtype_t type,
2541 void *arg,
2542 sctp_cmd_seq_t *commands)
2543{
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002544 return sctp_stop_t1_and_abort(net, commands, SCTP_ERROR_NO_ERROR,
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07002545 ENOPROTOOPT, asoc,
Frank Filz3f7a87d2005-06-20 13:14:57 -07002546 (struct sctp_transport *)arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002547}
2548
2549/*
2550 * Process an ABORT. (COOKIE-ECHOED state)
2551 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002552sctp_disposition_t sctp_sf_cookie_echoed_abort(struct net *net,
2553 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002554 const struct sctp_association *asoc,
2555 const sctp_subtype_t type,
2556 void *arg,
2557 sctp_cmd_seq_t *commands)
2558{
2559 /* There is a single T1 timer, so we should be able to use
2560 * common function with the COOKIE-WAIT state.
2561 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002562 return sctp_sf_cookie_wait_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002563}
2564
2565/*
2566 * Stop T1 timer and abort association with "INIT failed".
2567 *
2568 * This is common code called by several sctp_sf_*_abort() functions above.
2569 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002570static sctp_disposition_t sctp_stop_t1_and_abort(struct net *net,
2571 sctp_cmd_seq_t *commands,
Al Virof94c0192006-11-20 17:00:25 -08002572 __be16 error, int sk_err,
Frank Filz3f7a87d2005-06-20 13:14:57 -07002573 const struct sctp_association *asoc,
2574 struct sctp_transport *transport)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002575{
Daniel Borkmannbb333812013-06-28 19:49:40 +02002576 pr_debug("%s: ABORT received (INIT)\n", __func__);
2577
Linus Torvalds1da177e2005-04-16 15:20:36 -07002578 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
2579 SCTP_STATE(SCTP_STATE_CLOSED));
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002580 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002581 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
2582 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07002583 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002584 /* CMD_INIT_FAILED will DELETE_TCB. */
2585 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08002586 SCTP_PERR(error));
Daniel Borkmannbb333812013-06-28 19:49:40 +02002587
Frank Filz3f7a87d2005-06-20 13:14:57 -07002588 return SCTP_DISPOSITION_ABORT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002589}
2590
2591/*
2592 * sctp_sf_do_9_2_shut
2593 *
2594 * Section: 9.2
2595 * Upon the reception of the SHUTDOWN, the peer endpoint shall
2596 * - enter the SHUTDOWN-RECEIVED state,
2597 *
2598 * - stop accepting new data from its SCTP user
2599 *
2600 * - verify, by checking the Cumulative TSN Ack field of the chunk,
2601 * that all its outstanding DATA chunks have been received by the
2602 * SHUTDOWN sender.
2603 *
2604 * Once an endpoint as reached the SHUTDOWN-RECEIVED state it MUST NOT
2605 * send a SHUTDOWN in response to a ULP request. And should discard
2606 * subsequent SHUTDOWN chunks.
2607 *
2608 * If there are still outstanding DATA chunks left, the SHUTDOWN
2609 * receiver shall continue to follow normal data transmission
2610 * procedures defined in Section 6 until all outstanding DATA chunks
2611 * are acknowledged; however, the SHUTDOWN receiver MUST NOT accept
2612 * new data from its SCTP user.
2613 *
2614 * Verification Tag: 8.5 Verification Tag [Normal verification]
2615 *
2616 * Inputs
2617 * (endpoint, asoc, chunk)
2618 *
2619 * Outputs
2620 * (asoc, reply_msg, msg_up, timers, counters)
2621 *
2622 * The return value is the disposition of the chunk.
2623 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002624sctp_disposition_t sctp_sf_do_9_2_shutdown(struct net *net,
2625 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002626 const struct sctp_association *asoc,
2627 const sctp_subtype_t type,
2628 void *arg,
2629 sctp_cmd_seq_t *commands)
2630{
2631 struct sctp_chunk *chunk = arg;
2632 sctp_shutdownhdr_t *sdh;
2633 sctp_disposition_t disposition;
2634 struct sctp_ulpevent *ev;
Wei Yongjundf10eec2008-10-23 01:00:21 -07002635 __u32 ctsn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002636
2637 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002638 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002639
2640 /* Make sure that the SHUTDOWN chunk has a valid length. */
2641 if (!sctp_chunk_length_valid(chunk,
2642 sizeof(struct sctp_shutdown_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002643 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002644 commands);
2645
2646 /* Convert the elaborate header. */
2647 sdh = (sctp_shutdownhdr_t *)chunk->skb->data;
2648 skb_pull(chunk->skb, sizeof(sctp_shutdownhdr_t));
2649 chunk->subh.shutdown_hdr = sdh;
Wei Yongjundf10eec2008-10-23 01:00:21 -07002650 ctsn = ntohl(sdh->cum_tsn_ack);
2651
Wei Yongjuna2f36ee2009-08-22 11:24:00 +08002652 if (TSN_lt(ctsn, asoc->ctsn_ack_point)) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02002653 pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn,
2654 asoc->ctsn_ack_point);
2655
Wei Yongjuna2f36ee2009-08-22 11:24:00 +08002656 return SCTP_DISPOSITION_DISCARD;
2657 }
2658
Wei Yongjundf10eec2008-10-23 01:00:21 -07002659 /* If Cumulative TSN Ack beyond the max tsn currently
2660 * send, terminating the association and respond to the
2661 * sender with an ABORT.
2662 */
2663 if (!TSN_lt(ctsn, asoc->next_tsn))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002664 return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002665
Sridhar Samudralaeb0e0072005-09-22 23:48:38 -07002666 /* API 5.3.1.5 SCTP_SHUTDOWN_EVENT
2667 * When a peer sends a SHUTDOWN, SCTP delivers this notification to
2668 * inform the application that it should cease sending data.
2669 */
2670 ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC);
2671 if (!ev) {
2672 disposition = SCTP_DISPOSITION_NOMEM;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09002673 goto out;
Sridhar Samudralaeb0e0072005-09-22 23:48:38 -07002674 }
2675 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
2676
Linus Torvalds1da177e2005-04-16 15:20:36 -07002677 /* Upon the reception of the SHUTDOWN, the peer endpoint shall
2678 * - enter the SHUTDOWN-RECEIVED state,
2679 * - stop accepting new data from its SCTP user
2680 *
2681 * [This is implicit in the new state.]
2682 */
2683 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
2684 SCTP_STATE(SCTP_STATE_SHUTDOWN_RECEIVED));
2685 disposition = SCTP_DISPOSITION_CONSUME;
2686
2687 if (sctp_outq_is_empty(&asoc->outqueue)) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002688 disposition = sctp_sf_do_9_2_shutdown_ack(net, ep, asoc, type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002689 arg, commands);
2690 }
2691
2692 if (SCTP_DISPOSITION_NOMEM == disposition)
2693 goto out;
2694
2695 /* - verify, by checking the Cumulative TSN Ack field of the
2696 * chunk, that all its outstanding DATA chunks have been
2697 * received by the SHUTDOWN sender.
2698 */
2699 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN,
Al Viro2178eda2006-11-20 17:26:53 -08002700 SCTP_BE32(chunk->subh.shutdown_hdr->cum_tsn_ack));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002701
Linus Torvalds1da177e2005-04-16 15:20:36 -07002702out:
2703 return disposition;
2704}
2705
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002706/*
2707 * sctp_sf_do_9_2_shut_ctsn
2708 *
2709 * Once an endpoint has reached the SHUTDOWN-RECEIVED state,
2710 * it MUST NOT send a SHUTDOWN in response to a ULP request.
2711 * The Cumulative TSN Ack of the received SHUTDOWN chunk
2712 * MUST be processed.
2713 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002714sctp_disposition_t sctp_sf_do_9_2_shut_ctsn(struct net *net,
2715 const struct sctp_endpoint *ep,
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002716 const struct sctp_association *asoc,
2717 const sctp_subtype_t type,
2718 void *arg,
2719 sctp_cmd_seq_t *commands)
2720{
2721 struct sctp_chunk *chunk = arg;
2722 sctp_shutdownhdr_t *sdh;
Wei Yongjuna2f36ee2009-08-22 11:24:00 +08002723 __u32 ctsn;
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002724
2725 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002726 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002727
2728 /* Make sure that the SHUTDOWN chunk has a valid length. */
2729 if (!sctp_chunk_length_valid(chunk,
2730 sizeof(struct sctp_shutdown_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002731 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002732 commands);
2733
2734 sdh = (sctp_shutdownhdr_t *)chunk->skb->data;
Wei Yongjuna2f36ee2009-08-22 11:24:00 +08002735 ctsn = ntohl(sdh->cum_tsn_ack);
2736
2737 if (TSN_lt(ctsn, asoc->ctsn_ack_point)) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02002738 pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn,
2739 asoc->ctsn_ack_point);
2740
Wei Yongjuna2f36ee2009-08-22 11:24:00 +08002741 return SCTP_DISPOSITION_DISCARD;
2742 }
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002743
2744 /* If Cumulative TSN Ack beyond the max tsn currently
2745 * send, terminating the association and respond to the
2746 * sender with an ABORT.
2747 */
Wei Yongjuna2f36ee2009-08-22 11:24:00 +08002748 if (!TSN_lt(ctsn, asoc->next_tsn))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002749 return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands);
Wei Yongjun2e3f92d2008-10-23 01:01:18 -07002750
2751 /* verify, by checking the Cumulative TSN Ack field of the
2752 * chunk, that all its outstanding DATA chunks have been
2753 * received by the SHUTDOWN sender.
2754 */
2755 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN,
2756 SCTP_BE32(sdh->cum_tsn_ack));
2757
2758 return SCTP_DISPOSITION_CONSUME;
2759}
2760
Linus Torvalds1da177e2005-04-16 15:20:36 -07002761/* RFC 2960 9.2
2762 * If an endpoint is in SHUTDOWN-ACK-SENT state and receives an INIT chunk
2763 * (e.g., if the SHUTDOWN COMPLETE was lost) with source and destination
2764 * transport addresses (either in the IP addresses or in the INIT chunk)
2765 * that belong to this association, it should discard the INIT chunk and
2766 * retransmit the SHUTDOWN ACK chunk.
2767 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002768sctp_disposition_t sctp_sf_do_9_2_reshutack(struct net *net,
2769 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002770 const struct sctp_association *asoc,
2771 const sctp_subtype_t type,
2772 void *arg,
2773 sctp_cmd_seq_t *commands)
2774{
2775 struct sctp_chunk *chunk = (struct sctp_chunk *) arg;
2776 struct sctp_chunk *reply;
2777
Vlad Yasevichece25df2007-09-07 16:30:54 -04002778 /* Make sure that the chunk has a valid length */
2779 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002780 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04002781 commands);
2782
Linus Torvalds1da177e2005-04-16 15:20:36 -07002783 /* Since we are not going to really process this INIT, there
2784 * is no point in verifying chunk boundries. Just generate
2785 * the SHUTDOWN ACK.
2786 */
2787 reply = sctp_make_shutdown_ack(asoc, chunk);
2788 if (NULL == reply)
2789 goto nomem;
2790
2791 /* Set the transport for the SHUTDOWN ACK chunk and the timeout for
2792 * the T2-SHUTDOWN timer.
2793 */
2794 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
2795
2796 /* and restart the T2-shutdown timer. */
2797 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
2798 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
2799
2800 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
2801
2802 return SCTP_DISPOSITION_CONSUME;
2803nomem:
2804 return SCTP_DISPOSITION_NOMEM;
2805}
2806
2807/*
2808 * sctp_sf_do_ecn_cwr
2809 *
2810 * Section: Appendix A: Explicit Congestion Notification
2811 *
2812 * CWR:
2813 *
2814 * RFC 2481 details a specific bit for a sender to send in the header of
2815 * its next outbound TCP segment to indicate to its peer that it has
2816 * reduced its congestion window. This is termed the CWR bit. For
2817 * SCTP the same indication is made by including the CWR chunk.
2818 * This chunk contains one data element, i.e. the TSN number that
2819 * was sent in the ECNE chunk. This element represents the lowest
2820 * TSN number in the datagram that was originally marked with the
2821 * CE bit.
2822 *
2823 * Verification Tag: 8.5 Verification Tag [Normal verification]
2824 * Inputs
2825 * (endpoint, asoc, chunk)
2826 *
2827 * Outputs
2828 * (asoc, reply_msg, msg_up, timers, counters)
2829 *
2830 * The return value is the disposition of the chunk.
2831 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002832sctp_disposition_t sctp_sf_do_ecn_cwr(struct net *net,
2833 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002834 const struct sctp_association *asoc,
2835 const sctp_subtype_t type,
2836 void *arg,
2837 sctp_cmd_seq_t *commands)
2838{
2839 sctp_cwrhdr_t *cwr;
2840 struct sctp_chunk *chunk = arg;
Al Viro34bcca22006-11-20 17:27:15 -08002841 u32 lowest_tsn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002842
2843 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002844 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002845
2846 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002847 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002848 commands);
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09002849
Linus Torvalds1da177e2005-04-16 15:20:36 -07002850 cwr = (sctp_cwrhdr_t *) chunk->skb->data;
2851 skb_pull(chunk->skb, sizeof(sctp_cwrhdr_t));
2852
Al Viro34bcca22006-11-20 17:27:15 -08002853 lowest_tsn = ntohl(cwr->lowest_tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002854
2855 /* Does this CWR ack the last sent congestion notification? */
Al Viro34bcca22006-11-20 17:27:15 -08002856 if (TSN_lte(asoc->last_ecne_tsn, lowest_tsn)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002857 /* Stop sending ECNE. */
2858 sctp_add_cmd_sf(commands,
2859 SCTP_CMD_ECN_CWR,
Al Viro34bcca22006-11-20 17:27:15 -08002860 SCTP_U32(lowest_tsn));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002861 }
2862 return SCTP_DISPOSITION_CONSUME;
2863}
2864
2865/*
2866 * sctp_sf_do_ecne
2867 *
2868 * Section: Appendix A: Explicit Congestion Notification
2869 *
2870 * ECN-Echo
2871 *
2872 * RFC 2481 details a specific bit for a receiver to send back in its
2873 * TCP acknowledgements to notify the sender of the Congestion
2874 * Experienced (CE) bit having arrived from the network. For SCTP this
2875 * same indication is made by including the ECNE chunk. This chunk
2876 * contains one data element, i.e. the lowest TSN associated with the IP
2877 * datagram marked with the CE bit.....
2878 *
2879 * Verification Tag: 8.5 Verification Tag [Normal verification]
2880 * Inputs
2881 * (endpoint, asoc, chunk)
2882 *
2883 * Outputs
2884 * (asoc, reply_msg, msg_up, timers, counters)
2885 *
2886 * The return value is the disposition of the chunk.
2887 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002888sctp_disposition_t sctp_sf_do_ecne(struct net *net,
2889 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002890 const struct sctp_association *asoc,
2891 const sctp_subtype_t type,
2892 void *arg,
2893 sctp_cmd_seq_t *commands)
2894{
2895 sctp_ecnehdr_t *ecne;
2896 struct sctp_chunk *chunk = arg;
2897
2898 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002899 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002900
2901 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002902 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002903 commands);
2904
2905 ecne = (sctp_ecnehdr_t *) chunk->skb->data;
2906 skb_pull(chunk->skb, sizeof(sctp_ecnehdr_t));
2907
2908 /* If this is a newer ECNE than the last CWR packet we sent out */
2909 sctp_add_cmd_sf(commands, SCTP_CMD_ECN_ECNE,
2910 SCTP_U32(ntohl(ecne->lowest_tsn)));
2911
2912 return SCTP_DISPOSITION_CONSUME;
2913}
2914
2915/*
2916 * Section: 6.2 Acknowledgement on Reception of DATA Chunks
2917 *
2918 * The SCTP endpoint MUST always acknowledge the reception of each valid
2919 * DATA chunk.
2920 *
2921 * The guidelines on delayed acknowledgement algorithm specified in
2922 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an
2923 * acknowledgement SHOULD be generated for at least every second packet
2924 * (not every second DATA chunk) received, and SHOULD be generated within
2925 * 200 ms of the arrival of any unacknowledged DATA chunk. In some
2926 * situations it may be beneficial for an SCTP transmitter to be more
2927 * conservative than the algorithms detailed in this document allow.
2928 * However, an SCTP transmitter MUST NOT be more aggressive than the
2929 * following algorithms allow.
2930 *
2931 * A SCTP receiver MUST NOT generate more than one SACK for every
2932 * incoming packet, other than to update the offered window as the
2933 * receiving application consumes new data.
2934 *
2935 * Verification Tag: 8.5 Verification Tag [Normal verification]
2936 *
2937 * Inputs
2938 * (endpoint, asoc, chunk)
2939 *
2940 * Outputs
2941 * (asoc, reply_msg, msg_up, timers, counters)
2942 *
2943 * The return value is the disposition of the chunk.
2944 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002945sctp_disposition_t sctp_sf_eat_data_6_2(struct net *net,
2946 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002947 const struct sctp_association *asoc,
2948 const sctp_subtype_t type,
2949 void *arg,
2950 sctp_cmd_seq_t *commands)
2951{
2952 struct sctp_chunk *chunk = arg;
Wei Yongjun6dc76942009-11-23 15:53:53 -05002953 sctp_arg_t force = SCTP_NOFORCE();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002954 int error;
2955
2956 if (!sctp_vtag_verify(chunk, asoc)) {
2957 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
2958 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002959 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09002960 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002961
2962 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002963 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002964 commands);
2965
wangweidongcb3f8372013-12-23 12:16:50 +08002966 error = sctp_eat_data(asoc, chunk, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002967 switch (error) {
2968 case SCTP_IERROR_NO_ERROR:
2969 break;
2970 case SCTP_IERROR_HIGH_TSN:
2971 case SCTP_IERROR_BAD_STREAM:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002972 SCTP_INC_STATS(net, SCTP_MIB_IN_DATA_CHUNK_DISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002973 goto discard_noforce;
2974 case SCTP_IERROR_DUP_TSN:
2975 case SCTP_IERROR_IGNORE_TSN:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002976 SCTP_INC_STATS(net, SCTP_MIB_IN_DATA_CHUNK_DISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002977 goto discard_force;
2978 case SCTP_IERROR_NO_DATA:
Marcelo Ricardo Leitner649621e2016-01-08 11:00:54 -02002979 return SCTP_DISPOSITION_ABORT;
Vlad Yasevichf1751c52009-09-04 18:21:03 -04002980 case SCTP_IERROR_PROTO_VIOLATION:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00002981 return sctp_sf_abort_violation(net, ep, asoc, chunk, commands,
Vlad Yasevichf1751c52009-09-04 18:21:03 -04002982 (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002983 default:
2984 BUG();
2985 }
2986
Wei Yongjun6dc76942009-11-23 15:53:53 -05002987 if (chunk->chunk_hdr->flags & SCTP_DATA_SACK_IMM)
2988 force = SCTP_FORCE();
2989
Neil Horman9f70f462013-12-10 06:48:15 -05002990 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002991 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
2992 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
2993 }
2994
2995 /* If this is the last chunk in a packet, we need to count it
2996 * toward sack generation. Note that we need to SACK every
2997 * OTHER packet containing data chunks, EVEN IF WE DISCARD
2998 * THEM. We elect to NOT generate SACK's if the chunk fails
2999 * the verification tag test.
3000 *
3001 * RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks
3002 *
3003 * The SCTP endpoint MUST always acknowledge the reception of
3004 * each valid DATA chunk.
3005 *
3006 * The guidelines on delayed acknowledgement algorithm
3007 * specified in Section 4.2 of [RFC2581] SHOULD be followed.
3008 * Specifically, an acknowledgement SHOULD be generated for at
3009 * least every second packet (not every second DATA chunk)
3010 * received, and SHOULD be generated within 200 ms of the
3011 * arrival of any unacknowledged DATA chunk. In some
3012 * situations it may be beneficial for an SCTP transmitter to
3013 * be more conservative than the algorithms detailed in this
3014 * document allow. However, an SCTP transmitter MUST NOT be
3015 * more aggressive than the following algorithms allow.
3016 */
Frank Filz52ccb8e2005-12-22 11:36:46 -08003017 if (chunk->end_of_packet)
Wei Yongjun6dc76942009-11-23 15:53:53 -05003018 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003019
Linus Torvalds1da177e2005-04-16 15:20:36 -07003020 return SCTP_DISPOSITION_CONSUME;
3021
3022discard_force:
3023 /* RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks
3024 *
3025 * When a packet arrives with duplicate DATA chunk(s) and with
3026 * no new DATA chunk(s), the endpoint MUST immediately send a
3027 * SACK with no delay. If a packet arrives with duplicate
3028 * DATA chunk(s) bundled with new DATA chunks, the endpoint
3029 * MAY immediately send a SACK. Normally receipt of duplicate
3030 * DATA chunks will occur when the original SACK chunk was lost
3031 * and the peer's RTO has expired. The duplicate TSN number(s)
3032 * SHOULD be reported in the SACK as duplicate.
3033 */
3034 /* In our case, we split the MAY SACK advice up whether or not
3035 * the last chunk is a duplicate.'
3036 */
3037 if (chunk->end_of_packet)
3038 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
3039 return SCTP_DISPOSITION_DISCARD;
3040
3041discard_noforce:
Frank Filz52ccb8e2005-12-22 11:36:46 -08003042 if (chunk->end_of_packet)
Wei Yongjun6dc76942009-11-23 15:53:53 -05003043 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003044
Linus Torvalds1da177e2005-04-16 15:20:36 -07003045 return SCTP_DISPOSITION_DISCARD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003046}
3047
3048/*
3049 * sctp_sf_eat_data_fast_4_4
3050 *
3051 * Section: 4 (4)
3052 * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received
3053 * DATA chunks without delay.
3054 *
3055 * Verification Tag: 8.5 Verification Tag [Normal verification]
3056 * Inputs
3057 * (endpoint, asoc, chunk)
3058 *
3059 * Outputs
3060 * (asoc, reply_msg, msg_up, timers, counters)
3061 *
3062 * The return value is the disposition of the chunk.
3063 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003064sctp_disposition_t sctp_sf_eat_data_fast_4_4(struct net *net,
3065 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003066 const struct sctp_association *asoc,
3067 const sctp_subtype_t type,
3068 void *arg,
3069 sctp_cmd_seq_t *commands)
3070{
3071 struct sctp_chunk *chunk = arg;
3072 int error;
3073
3074 if (!sctp_vtag_verify(chunk, asoc)) {
3075 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3076 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003077 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003078 }
3079
3080 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003081 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003082 commands);
3083
wangweidongcb3f8372013-12-23 12:16:50 +08003084 error = sctp_eat_data(asoc, chunk, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003085 switch (error) {
3086 case SCTP_IERROR_NO_ERROR:
3087 case SCTP_IERROR_HIGH_TSN:
3088 case SCTP_IERROR_DUP_TSN:
3089 case SCTP_IERROR_IGNORE_TSN:
3090 case SCTP_IERROR_BAD_STREAM:
3091 break;
3092 case SCTP_IERROR_NO_DATA:
Marcelo Ricardo Leitner649621e2016-01-08 11:00:54 -02003093 return SCTP_DISPOSITION_ABORT;
Vlad Yasevichf1751c52009-09-04 18:21:03 -04003094 case SCTP_IERROR_PROTO_VIOLATION:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003095 return sctp_sf_abort_violation(net, ep, asoc, chunk, commands,
Vlad Yasevichf1751c52009-09-04 18:21:03 -04003096 (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003097 default:
3098 BUG();
3099 }
3100
3101 /* Go a head and force a SACK, since we are shutting down. */
3102
3103 /* Implementor's Guide.
3104 *
3105 * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately
3106 * respond to each received packet containing one or more DATA chunk(s)
3107 * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer
3108 */
3109 if (chunk->end_of_packet) {
3110 /* We must delay the chunk creation since the cumulative
3111 * TSN has not been updated yet.
3112 */
3113 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL());
3114 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
3115 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
3116 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
3117 }
3118
Linus Torvalds1da177e2005-04-16 15:20:36 -07003119 return SCTP_DISPOSITION_CONSUME;
3120}
3121
3122/*
3123 * Section: 6.2 Processing a Received SACK
3124 * D) Any time a SACK arrives, the endpoint performs the following:
3125 *
3126 * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point,
3127 * then drop the SACK. Since Cumulative TSN Ack is monotonically
3128 * increasing, a SACK whose Cumulative TSN Ack is less than the
3129 * Cumulative TSN Ack Point indicates an out-of-order SACK.
3130 *
3131 * ii) Set rwnd equal to the newly received a_rwnd minus the number
3132 * of bytes still outstanding after processing the Cumulative TSN Ack
3133 * and the Gap Ack Blocks.
3134 *
3135 * iii) If the SACK is missing a TSN that was previously
3136 * acknowledged via a Gap Ack Block (e.g., the data receiver
3137 * reneged on the data), then mark the corresponding DATA chunk
3138 * as available for retransmit: Mark it as missing for fast
3139 * retransmit as described in Section 7.2.4 and if no retransmit
3140 * timer is running for the destination address to which the DATA
3141 * chunk was originally transmitted, then T3-rtx is started for
3142 * that destination address.
3143 *
3144 * Verification Tag: 8.5 Verification Tag [Normal verification]
3145 *
3146 * Inputs
3147 * (endpoint, asoc, chunk)
3148 *
3149 * Outputs
3150 * (asoc, reply_msg, msg_up, timers, counters)
3151 *
3152 * The return value is the disposition of the chunk.
3153 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003154sctp_disposition_t sctp_sf_eat_sack_6_2(struct net *net,
3155 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003156 const struct sctp_association *asoc,
3157 const sctp_subtype_t type,
3158 void *arg,
3159 sctp_cmd_seq_t *commands)
3160{
3161 struct sctp_chunk *chunk = arg;
3162 sctp_sackhdr_t *sackh;
3163 __u32 ctsn;
3164
3165 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003166 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003167
3168 /* Make sure that the SACK chunk has a valid length. */
3169 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_sack_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003170 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003171 commands);
3172
3173 /* Pull the SACK chunk from the data buffer */
3174 sackh = sctp_sm_pull_sack(chunk);
3175 /* Was this a bogus SACK? */
3176 if (!sackh)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003177 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003178 chunk->subh.sack_hdr = sackh;
3179 ctsn = ntohl(sackh->cum_tsn_ack);
3180
3181 /* i) If Cumulative TSN Ack is less than the Cumulative TSN
3182 * Ack Point, then drop the SACK. Since Cumulative TSN
3183 * Ack is monotonically increasing, a SACK whose
3184 * Cumulative TSN Ack is less than the Cumulative TSN Ack
3185 * Point indicates an out-of-order SACK.
3186 */
3187 if (TSN_lt(ctsn, asoc->ctsn_ack_point)) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02003188 pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn,
3189 asoc->ctsn_ack_point);
3190
Linus Torvalds1da177e2005-04-16 15:20:36 -07003191 return SCTP_DISPOSITION_DISCARD;
3192 }
3193
Wei Yongjunaecedea2007-08-02 16:57:44 +08003194 /* If Cumulative TSN Ack beyond the max tsn currently
3195 * send, terminating the association and respond to the
3196 * sender with an ABORT.
3197 */
3198 if (!TSN_lt(ctsn, asoc->next_tsn))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003199 return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands);
Wei Yongjunaecedea2007-08-02 16:57:44 +08003200
Linus Torvalds1da177e2005-04-16 15:20:36 -07003201 /* Return this SACK for further processing. */
Nicolas Dichteledfee032012-10-03 05:43:22 +00003202 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_CHUNK(chunk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003203
3204 /* Note: We do the rest of the work on the PROCESS_SACK
3205 * sideeffect.
3206 */
3207 return SCTP_DISPOSITION_CONSUME;
3208}
3209
3210/*
3211 * Generate an ABORT in response to a packet.
3212 *
Jerome Forissier047a2422005-04-28 11:58:43 -07003213 * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41
Linus Torvalds1da177e2005-04-16 15:20:36 -07003214 *
Jerome Forissier047a2422005-04-28 11:58:43 -07003215 * 8) The receiver should respond to the sender of the OOTB packet with
3216 * an ABORT. When sending the ABORT, the receiver of the OOTB packet
3217 * MUST fill in the Verification Tag field of the outbound packet
3218 * with the value found in the Verification Tag field of the OOTB
3219 * packet and set the T-bit in the Chunk Flags to indicate that the
3220 * Verification Tag is reflected. After sending this ABORT, the
3221 * receiver of the OOTB packet shall discard the OOTB packet and take
3222 * no further action.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003223 *
3224 * Verification Tag:
3225 *
3226 * The return value is the disposition of the chunk.
3227*/
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003228static sctp_disposition_t sctp_sf_tabort_8_4_8(struct net *net,
3229 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003230 const struct sctp_association *asoc,
3231 const sctp_subtype_t type,
3232 void *arg,
3233 sctp_cmd_seq_t *commands)
3234{
3235 struct sctp_packet *packet = NULL;
3236 struct sctp_chunk *chunk = arg;
3237 struct sctp_chunk *abort;
3238
Eric W. Biederman2ce95502012-08-06 08:43:06 +00003239 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003240
3241 if (packet) {
3242 /* Make an ABORT. The T bit will be set if the asoc
3243 * is NULL.
3244 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003245 abort = sctp_make_abort(asoc, chunk, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003246 if (!abort) {
3247 sctp_ootb_pkt_free(packet);
3248 return SCTP_DISPOSITION_NOMEM;
3249 }
3250
Jerome Forissier047a2422005-04-28 11:58:43 -07003251 /* Reflect vtag if T-Bit is set */
3252 if (sctp_test_T_bit(abort))
3253 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
3254
Linus Torvalds1da177e2005-04-16 15:20:36 -07003255 /* Set the skb to the belonging sock for accounting. */
3256 abort->skb->sk = ep->base.sk;
3257
3258 sctp_packet_append_chunk(packet, abort);
3259
3260 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
3261 SCTP_PACKET(packet));
3262
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003263 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003264
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003265 sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003266 return SCTP_DISPOSITION_CONSUME;
3267 }
3268
3269 return SCTP_DISPOSITION_NOMEM;
3270}
3271
3272/*
3273 * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR
3274 * event as ULP notification for each cause included in the chunk.
3275 *
3276 * API 5.3.1.3 - SCTP_REMOTE_ERROR
3277 *
3278 * The return value is the disposition of the chunk.
3279*/
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003280sctp_disposition_t sctp_sf_operr_notify(struct net *net,
3281 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003282 const struct sctp_association *asoc,
3283 const sctp_subtype_t type,
3284 void *arg,
3285 sctp_cmd_seq_t *commands)
3286{
3287 struct sctp_chunk *chunk = arg;
Shan Wei8a00be12011-04-19 21:25:40 +00003288 sctp_errhdr_t *err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003289
3290 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003291 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003292
3293 /* Make sure that the ERROR chunk has a valid length. */
3294 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003295 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003296 commands);
Shan Wei8a00be12011-04-19 21:25:40 +00003297 sctp_walk_errors(err, chunk->chunk_hdr);
3298 if ((void *)err != (void *)chunk->chunk_end)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003299 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
Shan Wei8a00be12011-04-19 21:25:40 +00003300 (void *)err, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003301
Wei Yongjun3df26782009-03-02 06:46:51 +00003302 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR,
3303 SCTP_CHUNK(chunk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003304
Linus Torvalds1da177e2005-04-16 15:20:36 -07003305 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003306}
3307
3308/*
3309 * Process an inbound SHUTDOWN ACK.
3310 *
3311 * From Section 9.2:
3312 * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall
3313 * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its
3314 * peer, and remove all record of the association.
3315 *
3316 * The return value is the disposition.
3317 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003318sctp_disposition_t sctp_sf_do_9_2_final(struct net *net,
3319 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003320 const struct sctp_association *asoc,
3321 const sctp_subtype_t type,
3322 void *arg,
3323 sctp_cmd_seq_t *commands)
3324{
3325 struct sctp_chunk *chunk = arg;
3326 struct sctp_chunk *reply;
3327 struct sctp_ulpevent *ev;
3328
3329 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003330 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003331
3332 /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */
3333 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003334 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003335 commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003336 /* 10.2 H) SHUTDOWN COMPLETE notification
3337 *
3338 * When SCTP completes the shutdown procedures (section 9.2) this
3339 * notification is passed to the upper layer.
3340 */
3341 ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP,
Vlad Yasevicha5a35e72007-03-23 11:34:08 -07003342 0, 0, 0, NULL, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003343 if (!ev)
3344 goto nomem;
3345
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07003346 /* ...send a SHUTDOWN COMPLETE chunk to its peer, */
3347 reply = sctp_make_shutdown_complete(asoc, chunk);
3348 if (!reply)
3349 goto nomem_chunk;
3350
3351 /* Do all the commands now (after allocation), so that we
3352 * have consistent state if memory allocation failes
3353 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003354 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
3355
3356 /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall
3357 * stop the T2-shutdown timer,
3358 */
3359 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3360 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
3361
3362 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3363 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
3364
Linus Torvalds1da177e2005-04-16 15:20:36 -07003365 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
3366 SCTP_STATE(SCTP_STATE_CLOSED));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003367 SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS);
3368 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003369 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
3370
3371 /* ...and remove all record of the association. */
3372 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
3373 return SCTP_DISPOSITION_DELETE_TCB;
3374
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07003375nomem_chunk:
3376 sctp_ulpevent_free(ev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003377nomem:
3378 return SCTP_DISPOSITION_NOMEM;
3379}
3380
3381/*
Jerome Forissier047a2422005-04-28 11:58:43 -07003382 * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41.
3383 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07003384 * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should
3385 * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE.
3386 * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB
3387 * packet must fill in the Verification Tag field of the outbound
3388 * packet with the Verification Tag received in the SHUTDOWN ACK and
Jerome Forissier047a2422005-04-28 11:58:43 -07003389 * set the T-bit in the Chunk Flags to indicate that the Verification
3390 * Tag is reflected.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003391 *
3392 * 8) The receiver should respond to the sender of the OOTB packet with
3393 * an ABORT. When sending the ABORT, the receiver of the OOTB packet
3394 * MUST fill in the Verification Tag field of the outbound packet
3395 * with the value found in the Verification Tag field of the OOTB
Jerome Forissier047a2422005-04-28 11:58:43 -07003396 * packet and set the T-bit in the Chunk Flags to indicate that the
3397 * Verification Tag is reflected. After sending this ABORT, the
3398 * receiver of the OOTB packet shall discard the OOTB packet and take
3399 * no further action.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003400 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003401sctp_disposition_t sctp_sf_ootb(struct net *net,
3402 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003403 const struct sctp_association *asoc,
3404 const sctp_subtype_t type,
3405 void *arg,
3406 sctp_cmd_seq_t *commands)
3407{
3408 struct sctp_chunk *chunk = arg;
3409 struct sk_buff *skb = chunk->skb;
3410 sctp_chunkhdr_t *ch;
Shan Wei85c5ed42011-04-19 21:30:01 +00003411 sctp_errhdr_t *err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003412 __u8 *ch_end;
3413 int ootb_shut_ack = 0;
Shan Wei85c5ed42011-04-19 21:30:01 +00003414 int ootb_cookie_ack = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003415
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003416 SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003417
3418 ch = (sctp_chunkhdr_t *) chunk->chunk_hdr;
3419 do {
Vlad Yasevichece25df2007-09-07 16:30:54 -04003420 /* Report violation if the chunk is less then minimal */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003421 if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003422 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04003423 commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003424
Marcelo Ricardo Leitnerbf911e92016-10-25 14:27:39 -02003425 /* Report violation if chunk len overflows */
3426 ch_end = ((__u8 *)ch) + SCTP_PAD4(ntohs(ch->length));
3427 if (ch_end > skb_tail_pointer(skb))
3428 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
3429 commands);
3430
Vlad Yasevichece25df2007-09-07 16:30:54 -04003431 /* Now that we know we at least have a chunk header,
3432 * do things that are type appropriate.
3433 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003434 if (SCTP_CID_SHUTDOWN_ACK == ch->type)
3435 ootb_shut_ack = 1;
3436
3437 /* RFC 2960, Section 3.3.7
3438 * Moreover, under any circumstances, an endpoint that
3439 * receives an ABORT MUST NOT respond to that ABORT by
3440 * sending an ABORT of its own.
3441 */
3442 if (SCTP_CID_ABORT == ch->type)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003443 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003444
Shan Wei85c5ed42011-04-19 21:30:01 +00003445 /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR
3446 * or a COOKIE ACK the SCTP Packet should be silently
3447 * discarded.
3448 */
3449
3450 if (SCTP_CID_COOKIE_ACK == ch->type)
3451 ootb_cookie_ack = 1;
3452
3453 if (SCTP_CID_ERROR == ch->type) {
3454 sctp_walk_errors(err, ch) {
3455 if (SCTP_ERROR_STALE_COOKIE == err->cause) {
3456 ootb_cookie_ack = 1;
3457 break;
3458 }
3459 }
3460 }
3461
Linus Torvalds1da177e2005-04-16 15:20:36 -07003462 ch = (sctp_chunkhdr_t *) ch_end;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07003463 } while (ch_end < skb_tail_pointer(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003464
3465 if (ootb_shut_ack)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003466 return sctp_sf_shut_8_4_5(net, ep, asoc, type, arg, commands);
Shan Wei85c5ed42011-04-19 21:30:01 +00003467 else if (ootb_cookie_ack)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003468 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003469 else
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003470 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003471}
3472
3473/*
3474 * Handle an "Out of the blue" SHUTDOWN ACK.
3475 *
Jerome Forissier047a2422005-04-28 11:58:43 -07003476 * Section: 8.4 5, sctpimpguide 2.41.
3477 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07003478 * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should
Jerome Forissier047a2422005-04-28 11:58:43 -07003479 * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE.
3480 * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB
3481 * packet must fill in the Verification Tag field of the outbound
3482 * packet with the Verification Tag received in the SHUTDOWN ACK and
3483 * set the T-bit in the Chunk Flags to indicate that the Verification
3484 * Tag is reflected.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003485 *
3486 * Inputs
3487 * (endpoint, asoc, type, arg, commands)
3488 *
3489 * Outputs
3490 * (sctp_disposition_t)
3491 *
3492 * The return value is the disposition of the chunk.
3493 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003494static sctp_disposition_t sctp_sf_shut_8_4_5(struct net *net,
3495 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003496 const struct sctp_association *asoc,
3497 const sctp_subtype_t type,
3498 void *arg,
3499 sctp_cmd_seq_t *commands)
3500{
3501 struct sctp_packet *packet = NULL;
3502 struct sctp_chunk *chunk = arg;
3503 struct sctp_chunk *shut;
3504
Eric W. Biederman2ce95502012-08-06 08:43:06 +00003505 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003506
3507 if (packet) {
3508 /* Make an SHUTDOWN_COMPLETE.
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003509 * The T bit will be set if the asoc is NULL.
3510 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003511 shut = sctp_make_shutdown_complete(asoc, chunk);
3512 if (!shut) {
3513 sctp_ootb_pkt_free(packet);
3514 return SCTP_DISPOSITION_NOMEM;
3515 }
3516
Jerome Forissier047a2422005-04-28 11:58:43 -07003517 /* Reflect vtag if T-Bit is set */
3518 if (sctp_test_T_bit(shut))
3519 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
3520
Linus Torvalds1da177e2005-04-16 15:20:36 -07003521 /* Set the skb to the belonging sock for accounting. */
3522 shut->skb->sk = ep->base.sk;
3523
3524 sctp_packet_append_chunk(packet, shut);
3525
3526 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
3527 SCTP_PACKET(packet));
3528
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003529 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003530
3531 /* If the chunk length is invalid, we don't want to process
3532 * the reset of the packet.
3533 */
3534 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003535 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003536
Vlad Yasevichd3f25962007-09-07 11:47:45 -04003537 /* We need to discard the rest of the packet to prevent
3538 * potential bomming attacks from additional bundled chunks.
3539 * This is documented in SCTP Threats ID.
3540 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003541 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003542 }
3543
3544 return SCTP_DISPOSITION_NOMEM;
3545}
3546
3547/*
3548 * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state.
3549 *
3550 * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK
3551 * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the
3552 * procedures in section 8.4 SHOULD be followed, in other words it
3553 * should be treated as an Out Of The Blue packet.
3554 * [This means that we do NOT check the Verification Tag on these
3555 * chunks. --piggy ]
3556 *
3557 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003558sctp_disposition_t sctp_sf_do_8_5_1_E_sa(struct net *net,
3559 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003560 const struct sctp_association *asoc,
3561 const sctp_subtype_t type,
3562 void *arg,
3563 sctp_cmd_seq_t *commands)
3564{
Vlad Yasevichece25df2007-09-07 16:30:54 -04003565 struct sctp_chunk *chunk = arg;
3566
3567 /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */
3568 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003569 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04003570 commands);
3571
Linus Torvalds1da177e2005-04-16 15:20:36 -07003572 /* Although we do have an association in this case, it corresponds
3573 * to a restarted association. So the packet is treated as an OOTB
3574 * packet and the state function that handles OOTB SHUTDOWN_ACK is
3575 * called with a NULL association.
3576 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003577 SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
Wei Yongjun8190f892008-09-08 12:13:55 +08003578
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003579 return sctp_sf_shut_8_4_5(net, ep, NULL, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003580}
3581
3582/* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003583sctp_disposition_t sctp_sf_do_asconf(struct net *net,
3584 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003585 const struct sctp_association *asoc,
3586 const sctp_subtype_t type, void *arg,
3587 sctp_cmd_seq_t *commands)
3588{
3589 struct sctp_chunk *chunk = arg;
3590 struct sctp_chunk *asconf_ack = NULL;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003591 struct sctp_paramhdr *err_param = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003592 sctp_addiphdr_t *hdr;
3593 __u32 serial;
3594
3595 if (!sctp_vtag_verify(chunk, asoc)) {
3596 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3597 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003598 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003599 }
3600
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003601 /* ADD-IP: Section 4.1.1
3602 * This chunk MUST be sent in an authenticated way by using
3603 * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk
3604 * is received unauthenticated it MUST be silently discarded as
3605 * described in [I-D.ietf-tsvwg-sctp-auth].
3606 */
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00003607 if (!net->sctp.addip_noauth && !chunk->auth)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003608 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003609
Linus Torvalds1da177e2005-04-16 15:20:36 -07003610 /* Make sure that the ASCONF ADDIP chunk has a valid length. */
3611 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003612 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003613 commands);
3614
3615 hdr = (sctp_addiphdr_t *)chunk->skb->data;
3616 serial = ntohl(hdr->serial);
3617
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003618 /* Verify the ASCONF chunk before processing it. */
Daniel Borkmann9de79222014-10-09 22:55:31 +02003619 if (!sctp_verify_asconf(asoc, chunk, true, &err_param))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003620 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
Wei Yongjunba016672008-09-30 05:32:24 -07003621 (void *)err_param, commands);
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003622
Vlad Yasevicha08de642007-12-20 14:11:47 -08003623 /* ADDIP 5.2 E1) Compare the value of the serial number to the value
Linus Torvalds1da177e2005-04-16 15:20:36 -07003624 * the endpoint stored in a new association variable
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003625 * 'Peer-Serial-Number'.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003626 */
3627 if (serial == asoc->peer.addip_serial + 1) {
Vlad Yasevicha08de642007-12-20 14:11:47 -08003628 /* If this is the first instance of ASCONF in the packet,
3629 * we can clean our old ASCONF-ACKs.
3630 */
3631 if (!chunk->has_asconf)
3632 sctp_assoc_clean_asconf_ack_cache(asoc);
3633
3634 /* ADDIP 5.2 E4) When the Sequence Number matches the next one
3635 * expected, process the ASCONF as described below and after
3636 * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to
3637 * the response packet and cache a copy of it (in the event it
3638 * later needs to be retransmitted).
3639 *
3640 * Essentially, do V1-V5.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003641 */
3642 asconf_ack = sctp_process_asconf((struct sctp_association *)
3643 asoc, chunk);
3644 if (!asconf_ack)
3645 return SCTP_DISPOSITION_NOMEM;
Vlad Yasevicha08de642007-12-20 14:11:47 -08003646 } else if (serial < asoc->peer.addip_serial + 1) {
3647 /* ADDIP 5.2 E2)
3648 * If the value found in the Sequence Number is less than the
3649 * ('Peer- Sequence-Number' + 1), simply skip to the next
3650 * ASCONF, and include in the outbound response packet
3651 * any previously cached ASCONF-ACK response that was
3652 * sent and saved that matches the Sequence Number of the
3653 * ASCONF. Note: It is possible that no cached ASCONF-ACK
3654 * Chunk exists. This will occur when an older ASCONF
3655 * arrives out of order. In such a case, the receiver
3656 * should skip the ASCONF Chunk and not include ASCONF-ACK
3657 * Chunk for that chunk.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003658 */
Vlad Yasevicha08de642007-12-20 14:11:47 -08003659 asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial);
3660 if (!asconf_ack)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003661 return SCTP_DISPOSITION_DISCARD;
Vlad Yasevich31b02e12009-09-04 18:21:00 -04003662
3663 /* Reset the transport so that we select the correct one
3664 * this time around. This is to make sure that we don't
3665 * accidentally use a stale transport that's been removed.
3666 */
3667 asconf_ack->transport = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003668 } else {
Vlad Yasevicha08de642007-12-20 14:11:47 -08003669 /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since
Linus Torvalds1da177e2005-04-16 15:20:36 -07003670 * it must be either a stale packet or from an attacker.
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003671 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003672 return SCTP_DISPOSITION_DISCARD;
3673 }
3674
Vlad Yasevicha08de642007-12-20 14:11:47 -08003675 /* ADDIP 5.2 E6) The destination address of the SCTP packet
3676 * containing the ASCONF-ACK Chunks MUST be the source address of
3677 * the SCTP packet that held the ASCONF Chunks.
3678 *
3679 * To do this properly, we'll set the destination address of the chunk
3680 * and at the transmit time, will try look up the transport to use.
3681 * Since ASCONFs may be bundled, the correct transport may not be
Thadeu Lima de Souza Cascardo94e2bd62009-10-16 15:20:49 +02003682 * created until we process the entire packet, thus this workaround.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003683 */
Vlad Yasevicha08de642007-12-20 14:11:47 -08003684 asconf_ack->dest = chunk->source;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003685 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack));
Michio Honda6af29cc2011-06-16 17:14:34 +09003686 if (asoc->new_transport) {
wangweidongf7010e62013-12-23 12:16:52 +08003687 sctp_sf_heartbeat(ep, asoc, type, asoc->new_transport, commands);
Michio Honda6af29cc2011-06-16 17:14:34 +09003688 ((struct sctp_association *)asoc)->new_transport = NULL;
3689 }
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003690
Linus Torvalds1da177e2005-04-16 15:20:36 -07003691 return SCTP_DISPOSITION_CONSUME;
3692}
3693
3694/*
3695 * ADDIP Section 4.3 General rules for address manipulation
3696 * When building TLV parameters for the ASCONF Chunk that will add or
3697 * delete IP addresses the D0 to D13 rules should be applied:
3698 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003699sctp_disposition_t sctp_sf_do_asconf_ack(struct net *net,
3700 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003701 const struct sctp_association *asoc,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003702 const sctp_subtype_t type, void *arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003703 sctp_cmd_seq_t *commands)
3704{
3705 struct sctp_chunk *asconf_ack = arg;
3706 struct sctp_chunk *last_asconf = asoc->addip_last_asconf;
3707 struct sctp_chunk *abort;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003708 struct sctp_paramhdr *err_param = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003709 sctp_addiphdr_t *addip_hdr;
3710 __u32 sent_serial, rcvd_serial;
3711
3712 if (!sctp_vtag_verify(asconf_ack, asoc)) {
3713 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3714 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003715 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003716 }
3717
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003718 /* ADD-IP, Section 4.1.2:
3719 * This chunk MUST be sent in an authenticated way by using
3720 * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk
3721 * is received unauthenticated it MUST be silently discarded as
3722 * described in [I-D.ietf-tsvwg-sctp-auth].
3723 */
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00003724 if (!net->sctp.addip_noauth && !asconf_ack->auth)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003725 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003726
Linus Torvalds1da177e2005-04-16 15:20:36 -07003727 /* Make sure that the ADDIP chunk has a valid length. */
3728 if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003729 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003730 commands);
3731
3732 addip_hdr = (sctp_addiphdr_t *)asconf_ack->skb->data;
3733 rcvd_serial = ntohl(addip_hdr->serial);
3734
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003735 /* Verify the ASCONF-ACK chunk before processing it. */
Daniel Borkmann9de79222014-10-09 22:55:31 +02003736 if (!sctp_verify_asconf(asoc, asconf_ack, false, &err_param))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003737 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
Wei Yongjunba016672008-09-30 05:32:24 -07003738 (void *)err_param, commands);
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003739
Linus Torvalds1da177e2005-04-16 15:20:36 -07003740 if (last_asconf) {
3741 addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr;
3742 sent_serial = ntohl(addip_hdr->serial);
3743 } else {
3744 sent_serial = asoc->addip_serial - 1;
3745 }
3746
3747 /* D0) If an endpoint receives an ASCONF-ACK that is greater than or
3748 * equal to the next serial number to be used but no ASCONF chunk is
3749 * outstanding the endpoint MUST ABORT the association. Note that a
3750 * sequence number is greater than if it is no more than 2^^31-1
3751 * larger than the current sequence number (using serial arithmetic).
3752 */
3753 if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) &&
3754 !(asoc->addip_last_asconf)) {
3755 abort = sctp_make_abort(asoc, asconf_ack,
3756 sizeof(sctp_errhdr_t));
3757 if (abort) {
Wei Yongjun00f1c2d2007-08-21 15:50:01 +08003758 sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003759 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
3760 SCTP_CHUNK(abort));
3761 }
3762 /* We are going to ABORT, so we might as well stop
3763 * processing the rest of the chunks in the packet.
3764 */
3765 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3766 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
wangweidongcb3f8372013-12-23 12:16:50 +08003767 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07003768 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003769 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003770 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08003771 SCTP_PERR(SCTP_ERROR_ASCONF_ACK));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003772 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
3773 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003774 return SCTP_DISPOSITION_ABORT;
3775 }
3776
3777 if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) {
3778 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3779 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
3780
3781 if (!sctp_process_asconf_ack((struct sctp_association *)asoc,
Vlad Yasevichc0786692010-04-28 08:47:22 +00003782 asconf_ack)) {
3783 /* Successfully processed ASCONF_ACK. We can
3784 * release the next asconf if we have one.
3785 */
3786 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_NEXT_ASCONF,
3787 SCTP_NULL());
Linus Torvalds1da177e2005-04-16 15:20:36 -07003788 return SCTP_DISPOSITION_CONSUME;
Vlad Yasevichc0786692010-04-28 08:47:22 +00003789 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003790
3791 abort = sctp_make_abort(asoc, asconf_ack,
3792 sizeof(sctp_errhdr_t));
3793 if (abort) {
Wei Yongjun00f1c2d2007-08-21 15:50:01 +08003794 sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003795 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
3796 SCTP_CHUNK(abort));
3797 }
3798 /* We are going to ABORT, so we might as well stop
3799 * processing the rest of the chunks in the packet.
3800 */
wangweidongcb3f8372013-12-23 12:16:50 +08003801 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07003802 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003803 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003804 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08003805 SCTP_PERR(SCTP_ERROR_ASCONF_ACK));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003806 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
3807 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003808 return SCTP_DISPOSITION_ABORT;
3809 }
3810
3811 return SCTP_DISPOSITION_DISCARD;
3812}
3813
3814/*
3815 * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP
3816 *
3817 * When a FORWARD TSN chunk arrives, the data receiver MUST first update
3818 * its cumulative TSN point to the value carried in the FORWARD TSN
3819 * chunk, and then MUST further advance its cumulative TSN point locally
3820 * if possible.
3821 * After the above processing, the data receiver MUST stop reporting any
3822 * missing TSNs earlier than or equal to the new cumulative TSN point.
3823 *
3824 * Verification Tag: 8.5 Verification Tag [Normal verification]
3825 *
3826 * The return value is the disposition of the chunk.
3827 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003828sctp_disposition_t sctp_sf_eat_fwd_tsn(struct net *net,
3829 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003830 const struct sctp_association *asoc,
3831 const sctp_subtype_t type,
3832 void *arg,
3833 sctp_cmd_seq_t *commands)
3834{
3835 struct sctp_chunk *chunk = arg;
3836 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003837 struct sctp_fwdtsn_skip *skip;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003838 __u16 len;
3839 __u32 tsn;
3840
3841 if (!sctp_vtag_verify(chunk, asoc)) {
3842 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3843 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003844 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003845 }
3846
3847 /* Make sure that the FORWARD_TSN chunk has valid length. */
3848 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003849 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003850 commands);
3851
3852 fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data;
3853 chunk->subh.fwdtsn_hdr = fwdtsn_hdr;
3854 len = ntohs(chunk->chunk_hdr->length);
3855 len -= sizeof(struct sctp_chunkhdr);
3856 skb_pull(chunk->skb, len);
3857
3858 tsn = ntohl(fwdtsn_hdr->new_cum_tsn);
Daniel Borkmannbb333812013-06-28 19:49:40 +02003859 pr_debug("%s: TSN 0x%x\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003860
3861 /* The TSN is too high--silently discard the chunk and count on it
3862 * getting retransmitted later.
3863 */
3864 if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0)
3865 goto discard_noforce;
3866
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003867 /* Silently discard the chunk if stream-id is not valid */
3868 sctp_walk_fwdtsn(skip, chunk) {
3869 if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams)
3870 goto discard_noforce;
3871 }
3872
Linus Torvalds1da177e2005-04-16 15:20:36 -07003873 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn));
3874 if (len > sizeof(struct sctp_fwdtsn_hdr))
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003875 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003876 SCTP_CHUNK(chunk));
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003877
Linus Torvalds1da177e2005-04-16 15:20:36 -07003878 /* Count this as receiving DATA. */
Neil Horman9f70f462013-12-10 06:48:15 -05003879 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003880 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
3881 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
3882 }
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003883
Linus Torvalds1da177e2005-04-16 15:20:36 -07003884 /* FIXME: For now send a SACK, but DATA processing may
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003885 * send another.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003886 */
3887 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE());
Linus Torvalds1da177e2005-04-16 15:20:36 -07003888
3889 return SCTP_DISPOSITION_CONSUME;
3890
3891discard_noforce:
3892 return SCTP_DISPOSITION_DISCARD;
3893}
3894
3895sctp_disposition_t sctp_sf_eat_fwd_tsn_fast(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003896 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003897 const struct sctp_endpoint *ep,
3898 const struct sctp_association *asoc,
3899 const sctp_subtype_t type,
3900 void *arg,
3901 sctp_cmd_seq_t *commands)
3902{
3903 struct sctp_chunk *chunk = arg;
3904 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003905 struct sctp_fwdtsn_skip *skip;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003906 __u16 len;
3907 __u32 tsn;
3908
3909 if (!sctp_vtag_verify(chunk, asoc)) {
3910 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3911 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003912 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003913 }
3914
3915 /* Make sure that the FORWARD_TSN chunk has a valid length. */
3916 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003917 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003918 commands);
3919
3920 fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data;
3921 chunk->subh.fwdtsn_hdr = fwdtsn_hdr;
3922 len = ntohs(chunk->chunk_hdr->length);
3923 len -= sizeof(struct sctp_chunkhdr);
3924 skb_pull(chunk->skb, len);
3925
3926 tsn = ntohl(fwdtsn_hdr->new_cum_tsn);
Daniel Borkmannbb333812013-06-28 19:49:40 +02003927 pr_debug("%s: TSN 0x%x\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003928
3929 /* The TSN is too high--silently discard the chunk and count on it
3930 * getting retransmitted later.
3931 */
3932 if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0)
3933 goto gen_shutdown;
3934
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003935 /* Silently discard the chunk if stream-id is not valid */
3936 sctp_walk_fwdtsn(skip, chunk) {
3937 if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams)
3938 goto gen_shutdown;
3939 }
3940
Linus Torvalds1da177e2005-04-16 15:20:36 -07003941 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn));
3942 if (len > sizeof(struct sctp_fwdtsn_hdr))
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003943 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003944 SCTP_CHUNK(chunk));
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003945
Linus Torvalds1da177e2005-04-16 15:20:36 -07003946 /* Go a head and force a SACK, since we are shutting down. */
3947gen_shutdown:
3948 /* Implementor's Guide.
3949 *
3950 * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately
3951 * respond to each received packet containing one or more DATA chunk(s)
3952 * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer
3953 */
3954 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL());
3955 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
3956 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
3957 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
3958
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003959 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003960}
3961
3962/*
Lucas De Marchi25985ed2011-03-30 22:57:33 -03003963 * SCTP-AUTH Section 6.3 Receiving authenticated chukns
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07003964 *
3965 * The receiver MUST use the HMAC algorithm indicated in the HMAC
3966 * Identifier field. If this algorithm was not specified by the
3967 * receiver in the HMAC-ALGO parameter in the INIT or INIT-ACK chunk
3968 * during association setup, the AUTH chunk and all chunks after it MUST
3969 * be discarded and an ERROR chunk SHOULD be sent with the error cause
3970 * defined in Section 4.1.
3971 *
3972 * If an endpoint with no shared key receives a Shared Key Identifier
3973 * other than 0, it MUST silently discard all authenticated chunks. If
3974 * the endpoint has at least one endpoint pair shared key for the peer,
3975 * it MUST use the key specified by the Shared Key Identifier if a
3976 * key has been configured for that Shared Key Identifier. If no
3977 * endpoint pair shared key has been configured for that Shared Key
3978 * Identifier, all authenticated chunks MUST be silently discarded.
3979 *
3980 * Verification Tag: 8.5 Verification Tag [Normal verification]
3981 *
3982 * The return value is the disposition of the chunk.
3983 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003984static sctp_ierror_t sctp_sf_authenticate(struct net *net,
3985 const struct sctp_endpoint *ep,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07003986 const struct sctp_association *asoc,
3987 const sctp_subtype_t type,
3988 struct sctp_chunk *chunk)
3989{
3990 struct sctp_authhdr *auth_hdr;
3991 struct sctp_hmac *hmac;
3992 unsigned int sig_len;
3993 __u16 key_id;
3994 __u8 *save_digest;
3995 __u8 *digest;
3996
3997 /* Pull in the auth header, so we can do some more verification */
3998 auth_hdr = (struct sctp_authhdr *)chunk->skb->data;
3999 chunk->subh.auth_hdr = auth_hdr;
4000 skb_pull(chunk->skb, sizeof(struct sctp_authhdr));
4001
Masanari Iida02582e92012-08-22 19:11:26 +09004002 /* Make sure that we support the HMAC algorithm from the auth
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004003 * chunk.
4004 */
4005 if (!sctp_auth_asoc_verify_hmac_id(asoc, auth_hdr->hmac_id))
4006 return SCTP_IERROR_AUTH_BAD_HMAC;
4007
4008 /* Make sure that the provided shared key identifier has been
4009 * configured
4010 */
4011 key_id = ntohs(auth_hdr->shkey_id);
4012 if (key_id != asoc->active_key_id && !sctp_auth_get_shkey(asoc, key_id))
4013 return SCTP_IERROR_AUTH_BAD_KEYID;
4014
4015
4016 /* Make sure that the length of the signature matches what
4017 * we expect.
4018 */
4019 sig_len = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_auth_chunk_t);
4020 hmac = sctp_auth_get_hmac(ntohs(auth_hdr->hmac_id));
4021 if (sig_len != hmac->hmac_len)
4022 return SCTP_IERROR_PROTO_VIOLATION;
4023
4024 /* Now that we've done validation checks, we can compute and
4025 * verify the hmac. The steps involved are:
4026 * 1. Save the digest from the chunk.
4027 * 2. Zero out the digest in the chunk.
4028 * 3. Compute the new digest
4029 * 4. Compare saved and new digests.
4030 */
4031 digest = auth_hdr->hmac;
4032 skb_pull(chunk->skb, sig_len);
4033
4034 save_digest = kmemdup(digest, sig_len, GFP_ATOMIC);
4035 if (!save_digest)
4036 goto nomem;
4037
4038 memset(digest, 0, sig_len);
4039
4040 sctp_auth_calculate_hmac(asoc, chunk->skb,
4041 (struct sctp_auth_chunk *)chunk->chunk_hdr,
4042 GFP_ATOMIC);
4043
4044 /* Discard the packet if the digests do not match */
4045 if (memcmp(save_digest, digest, sig_len)) {
4046 kfree(save_digest);
4047 return SCTP_IERROR_BAD_SIG;
4048 }
4049
4050 kfree(save_digest);
4051 chunk->auth = 1;
4052
4053 return SCTP_IERROR_NO_ERROR;
4054nomem:
4055 return SCTP_IERROR_NOMEM;
4056}
4057
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004058sctp_disposition_t sctp_sf_eat_auth(struct net *net,
4059 const struct sctp_endpoint *ep,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004060 const struct sctp_association *asoc,
4061 const sctp_subtype_t type,
4062 void *arg,
4063 sctp_cmd_seq_t *commands)
4064{
4065 struct sctp_authhdr *auth_hdr;
4066 struct sctp_chunk *chunk = arg;
4067 struct sctp_chunk *err_chunk;
4068 sctp_ierror_t error;
4069
Wei Yongjund2f19fa2008-02-05 03:02:26 -08004070 /* Make sure that the peer has AUTH capable */
4071 if (!asoc->peer.auth_capable)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004072 return sctp_sf_unk_chunk(net, ep, asoc, type, arg, commands);
Wei Yongjund2f19fa2008-02-05 03:02:26 -08004073
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004074 if (!sctp_vtag_verify(chunk, asoc)) {
4075 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
4076 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004077 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004078 }
4079
4080 /* Make sure that the AUTH chunk has valid length. */
4081 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_auth_chunk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004082 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004083 commands);
4084
4085 auth_hdr = (struct sctp_authhdr *)chunk->skb->data;
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004086 error = sctp_sf_authenticate(net, ep, asoc, type, chunk);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004087 switch (error) {
Joe Perches7fd71b12011-07-01 09:43:11 +00004088 case SCTP_IERROR_AUTH_BAD_HMAC:
4089 /* Generate the ERROR chunk and discard the rest
4090 * of the packet
4091 */
4092 err_chunk = sctp_make_op_error(asoc, chunk,
4093 SCTP_ERROR_UNSUP_HMAC,
4094 &auth_hdr->hmac_id,
4095 sizeof(__u16), 0);
4096 if (err_chunk) {
4097 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
4098 SCTP_CHUNK(err_chunk));
4099 }
4100 /* Fall Through */
4101 case SCTP_IERROR_AUTH_BAD_KEYID:
4102 case SCTP_IERROR_BAD_SIG:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004103 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Joe Perches7fd71b12011-07-01 09:43:11 +00004104
4105 case SCTP_IERROR_PROTO_VIOLATION:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004106 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Joe Perches7fd71b12011-07-01 09:43:11 +00004107 commands);
4108
4109 case SCTP_IERROR_NOMEM:
4110 return SCTP_DISPOSITION_NOMEM;
4111
4112 default: /* Prevent gcc warnings */
4113 break;
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004114 }
4115
Vlad Yasevich65b07e52007-09-16 19:34:00 -07004116 if (asoc->active_key_id != ntohs(auth_hdr->shkey_id)) {
4117 struct sctp_ulpevent *ev;
4118
4119 ev = sctp_ulpevent_make_authkey(asoc, ntohs(auth_hdr->shkey_id),
4120 SCTP_AUTH_NEWKEY, GFP_ATOMIC);
4121
4122 if (!ev)
4123 return -ENOMEM;
4124
4125 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
4126 SCTP_ULPEVENT(ev));
4127 }
4128
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004129 return SCTP_DISPOSITION_CONSUME;
4130}
4131
4132/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07004133 * Process an unknown chunk.
4134 *
4135 * Section: 3.2. Also, 2.1 in the implementor's guide.
4136 *
4137 * Chunk Types are encoded such that the highest-order two bits specify
4138 * the action that must be taken if the processing endpoint does not
4139 * recognize the Chunk Type.
4140 *
4141 * 00 - Stop processing this SCTP packet and discard it, do not process
4142 * any further chunks within it.
4143 *
4144 * 01 - Stop processing this SCTP packet and discard it, do not process
4145 * any further chunks within it, and report the unrecognized
4146 * chunk in an 'Unrecognized Chunk Type'.
4147 *
4148 * 10 - Skip this chunk and continue processing.
4149 *
4150 * 11 - Skip this chunk and continue processing, but report in an ERROR
4151 * Chunk using the 'Unrecognized Chunk Type' cause of error.
4152 *
4153 * The return value is the disposition of the chunk.
4154 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004155sctp_disposition_t sctp_sf_unk_chunk(struct net *net,
4156 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004157 const struct sctp_association *asoc,
4158 const sctp_subtype_t type,
4159 void *arg,
4160 sctp_cmd_seq_t *commands)
4161{
4162 struct sctp_chunk *unk_chunk = arg;
4163 struct sctp_chunk *err_chunk;
4164 sctp_chunkhdr_t *hdr;
4165
Daniel Borkmannbb333812013-06-28 19:49:40 +02004166 pr_debug("%s: processing unknown chunk id:%d\n", __func__, type.chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004167
4168 if (!sctp_vtag_verify(unk_chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004169 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004170
4171 /* Make sure that the chunk has a valid length.
4172 * Since we don't know the chunk type, we use a general
4173 * chunkhdr structure to make a comparison.
4174 */
4175 if (!sctp_chunk_length_valid(unk_chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004176 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004177 commands);
4178
4179 switch (type.chunk & SCTP_CID_ACTION_MASK) {
4180 case SCTP_CID_ACTION_DISCARD:
4181 /* Discard the packet. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004182 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004183 case SCTP_CID_ACTION_DISCARD_ERR:
Linus Torvalds1da177e2005-04-16 15:20:36 -07004184 /* Generate an ERROR chunk as response. */
4185 hdr = unk_chunk->chunk_hdr;
4186 err_chunk = sctp_make_op_error(asoc, unk_chunk,
4187 SCTP_ERROR_UNKNOWN_CHUNK, hdr,
Marcelo Ricardo Leitnere2f036a2016-09-21 08:45:55 -03004188 SCTP_PAD4(ntohs(hdr->length)),
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05004189 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004190 if (err_chunk) {
4191 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
4192 SCTP_CHUNK(err_chunk));
4193 }
Vlad Yasevich2e3216c2008-06-19 16:08:18 -07004194
4195 /* Discard the packet. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004196 sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004197 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004198 case SCTP_CID_ACTION_SKIP:
4199 /* Skip the chunk. */
4200 return SCTP_DISPOSITION_DISCARD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004201 case SCTP_CID_ACTION_SKIP_ERR:
4202 /* Generate an ERROR chunk as response. */
4203 hdr = unk_chunk->chunk_hdr;
4204 err_chunk = sctp_make_op_error(asoc, unk_chunk,
4205 SCTP_ERROR_UNKNOWN_CHUNK, hdr,
Marcelo Ricardo Leitnere2f036a2016-09-21 08:45:55 -03004206 SCTP_PAD4(ntohs(hdr->length)),
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05004207 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004208 if (err_chunk) {
4209 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
4210 SCTP_CHUNK(err_chunk));
4211 }
4212 /* Skip the chunk. */
4213 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004214 default:
4215 break;
4216 }
4217
4218 return SCTP_DISPOSITION_DISCARD;
4219}
4220
4221/*
4222 * Discard the chunk.
4223 *
4224 * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2
4225 * [Too numerous to mention...]
4226 * Verification Tag: No verification needed.
4227 * Inputs
4228 * (endpoint, asoc, chunk)
4229 *
4230 * Outputs
4231 * (asoc, reply_msg, msg_up, timers, counters)
4232 *
4233 * The return value is the disposition of the chunk.
4234 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004235sctp_disposition_t sctp_sf_discard_chunk(struct net *net,
4236 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004237 const struct sctp_association *asoc,
4238 const sctp_subtype_t type,
4239 void *arg,
4240 sctp_cmd_seq_t *commands)
4241{
Vlad Yasevichece25df2007-09-07 16:30:54 -04004242 struct sctp_chunk *chunk = arg;
4243
4244 /* Make sure that the chunk has a valid length.
4245 * Since we don't know the chunk type, we use a general
4246 * chunkhdr structure to make a comparison.
4247 */
4248 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004249 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004250 commands);
4251
Daniel Borkmannbb333812013-06-28 19:49:40 +02004252 pr_debug("%s: chunk:%d is discarded\n", __func__, type.chunk);
4253
Linus Torvalds1da177e2005-04-16 15:20:36 -07004254 return SCTP_DISPOSITION_DISCARD;
4255}
4256
4257/*
4258 * Discard the whole packet.
4259 *
4260 * Section: 8.4 2)
4261 *
4262 * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST
4263 * silently discard the OOTB packet and take no further action.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004264 *
4265 * Verification Tag: No verification necessary
4266 *
4267 * Inputs
4268 * (endpoint, asoc, chunk)
4269 *
4270 * Outputs
4271 * (asoc, reply_msg, msg_up, timers, counters)
4272 *
4273 * The return value is the disposition of the chunk.
4274 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004275sctp_disposition_t sctp_sf_pdiscard(struct net *net,
4276 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004277 const struct sctp_association *asoc,
4278 const sctp_subtype_t type,
4279 void *arg,
4280 sctp_cmd_seq_t *commands)
4281{
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004282 SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_DISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004283 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
4284
4285 return SCTP_DISPOSITION_CONSUME;
4286}
4287
4288
4289/*
4290 * The other end is violating protocol.
4291 *
4292 * Section: Not specified
4293 * Verification Tag: Not specified
4294 * Inputs
4295 * (endpoint, asoc, chunk)
4296 *
4297 * Outputs
4298 * (asoc, reply_msg, msg_up, timers, counters)
4299 *
4300 * We simply tag the chunk as a violation. The state machine will log
4301 * the violation and continue.
4302 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004303sctp_disposition_t sctp_sf_violation(struct net *net,
4304 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004305 const struct sctp_association *asoc,
4306 const sctp_subtype_t type,
4307 void *arg,
4308 sctp_cmd_seq_t *commands)
4309{
Vlad Yasevichece25df2007-09-07 16:30:54 -04004310 struct sctp_chunk *chunk = arg;
4311
4312 /* Make sure that the chunk has a valid length. */
4313 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004314 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004315 commands);
4316
Linus Torvalds1da177e2005-04-16 15:20:36 -07004317 return SCTP_DISPOSITION_VIOLATION;
4318}
4319
Linus Torvalds1da177e2005-04-16 15:20:36 -07004320/*
Wei Yongjunaecedea2007-08-02 16:57:44 +08004321 * Common function to handle a protocol violation.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004322 */
Wei Yongjunaecedea2007-08-02 16:57:44 +08004323static sctp_disposition_t sctp_sf_abort_violation(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004324 struct net *net,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004325 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004326 const struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004327 void *arg,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004328 sctp_cmd_seq_t *commands,
4329 const __u8 *payload,
4330 const size_t paylen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004331{
Vlad Yasevichece25df2007-09-07 16:30:54 -04004332 struct sctp_packet *packet = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004333 struct sctp_chunk *chunk = arg;
4334 struct sctp_chunk *abort = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004335
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004336 /* SCTP-AUTH, Section 6.3:
4337 * It should be noted that if the receiver wants to tear
4338 * down an association in an authenticated way only, the
4339 * handling of malformed packets should not result in
4340 * tearing down the association.
4341 *
4342 * This means that if we only want to abort associations
4343 * in an authenticated way (i.e AUTH+ABORT), then we
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004344 * can't destroy this association just because the packet
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004345 * was malformed.
4346 */
4347 if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc))
4348 goto discard;
4349
Jesper Juhl9abed242007-11-11 23:57:49 +01004350 /* Make the abort chunk. */
4351 abort = sctp_make_abort_violation(asoc, chunk, payload, paylen);
4352 if (!abort)
4353 goto nomem;
4354
Vlad Yasevichece25df2007-09-07 16:30:54 -04004355 if (asoc) {
Gui Jianfengf4ad85c2008-04-12 18:39:34 -07004356 /* Treat INIT-ACK as a special case during COOKIE-WAIT. */
4357 if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK &&
4358 !asoc->peer.i.init_tag) {
4359 sctp_initack_chunk_t *initack;
4360
4361 initack = (sctp_initack_chunk_t *)chunk->chunk_hdr;
4362 if (!sctp_chunk_length_valid(chunk,
4363 sizeof(sctp_initack_chunk_t)))
4364 abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T;
4365 else {
4366 unsigned int inittag;
4367
4368 inittag = ntohl(initack->init_hdr.init_tag);
4369 sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG,
4370 SCTP_U32(inittag));
4371 }
4372 }
4373
Vlad Yasevichece25df2007-09-07 16:30:54 -04004374 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004375 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004376
Vlad Yasevichece25df2007-09-07 16:30:54 -04004377 if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) {
4378 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
4379 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4380 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4381 SCTP_ERROR(ECONNREFUSED));
4382 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
4383 SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION));
4384 } else {
4385 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4386 SCTP_ERROR(ECONNABORTED));
4387 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
4388 SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004389 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Vlad Yasevichece25df2007-09-07 16:30:54 -04004390 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004391 } else {
Eric W. Biederman2ce95502012-08-06 08:43:06 +00004392 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Vlad Yasevichece25df2007-09-07 16:30:54 -04004393
4394 if (!packet)
4395 goto nomem_pkt;
4396
4397 if (sctp_test_T_bit(abort))
4398 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
4399
4400 abort->skb->sk = ep->base.sk;
4401
4402 sctp_packet_append_chunk(packet, abort);
4403
4404 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
4405 SCTP_PACKET(packet));
4406
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004407 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004408 }
4409
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004410 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09004411
Vlad Yasevich56eb82b2008-10-09 14:33:01 -07004412discard:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004413 sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004414 return SCTP_DISPOSITION_ABORT;
4415
Vlad Yasevichece25df2007-09-07 16:30:54 -04004416nomem_pkt:
4417 sctp_chunk_free(abort);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004418nomem:
4419 return SCTP_DISPOSITION_NOMEM;
4420}
4421
Wei Yongjunaecedea2007-08-02 16:57:44 +08004422/*
4423 * Handle a protocol violation when the chunk length is invalid.
Frederik Schwarzer025dfda2008-10-16 19:02:37 +02004424 * "Invalid" length is identified as smaller than the minimal length a
Wei Yongjunaecedea2007-08-02 16:57:44 +08004425 * given chunk can be. For example, a SACK chunk has invalid length
Frederik Schwarzer025dfda2008-10-16 19:02:37 +02004426 * if its length is set to be smaller than the size of sctp_sack_chunk_t.
Wei Yongjunaecedea2007-08-02 16:57:44 +08004427 *
4428 * We inform the other end by sending an ABORT with a Protocol Violation
4429 * error code.
4430 *
4431 * Section: Not specified
4432 * Verification Tag: Nothing to do
4433 * Inputs
4434 * (endpoint, asoc, chunk)
4435 *
4436 * Outputs
4437 * (reply_msg, msg_up, counters)
4438 *
4439 * Generate an ABORT chunk and terminate the association.
4440 */
4441static sctp_disposition_t sctp_sf_violation_chunklen(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004442 struct net *net,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004443 const struct sctp_endpoint *ep,
4444 const struct sctp_association *asoc,
4445 const sctp_subtype_t type,
4446 void *arg,
4447 sctp_cmd_seq_t *commands)
4448{
wangweidongcb3f8372013-12-23 12:16:50 +08004449 static const char err_str[] = "The following chunk had invalid length:";
Wei Yongjunaecedea2007-08-02 16:57:44 +08004450
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004451 return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004452 sizeof(err_str));
4453}
4454
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004455/*
4456 * Handle a protocol violation when the parameter length is invalid.
Shan Wei33c7cfd2011-04-18 19:11:01 +00004457 * If the length is smaller than the minimum length of a given parameter,
4458 * or accumulated length in multi parameters exceeds the end of the chunk,
4459 * the length is considered as invalid.
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004460 */
4461static sctp_disposition_t sctp_sf_violation_paramlen(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004462 struct net *net,
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004463 const struct sctp_endpoint *ep,
4464 const struct sctp_association *asoc,
4465 const sctp_subtype_t type,
Wei Yongjunba016672008-09-30 05:32:24 -07004466 void *arg, void *ext,
4467 sctp_cmd_seq_t *commands)
4468{
4469 struct sctp_chunk *chunk = arg;
4470 struct sctp_paramhdr *param = ext;
4471 struct sctp_chunk *abort = NULL;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004472
Wei Yongjunba016672008-09-30 05:32:24 -07004473 if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc))
4474 goto discard;
4475
4476 /* Make the abort chunk. */
4477 abort = sctp_make_violation_paramlen(asoc, chunk, param);
4478 if (!abort)
4479 goto nomem;
4480
4481 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004482 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Wei Yongjunba016672008-09-30 05:32:24 -07004483
4484 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4485 SCTP_ERROR(ECONNABORTED));
4486 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
4487 SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004488 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
4489 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
Wei Yongjunba016672008-09-30 05:32:24 -07004490
4491discard:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004492 sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands);
Wei Yongjunba016672008-09-30 05:32:24 -07004493 return SCTP_DISPOSITION_ABORT;
4494nomem:
4495 return SCTP_DISPOSITION_NOMEM;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004496}
4497
Wei Yongjunaecedea2007-08-02 16:57:44 +08004498/* Handle a protocol violation when the peer trying to advance the
4499 * cumulative tsn ack to a point beyond the max tsn currently sent.
4500 *
4501 * We inform the other end by sending an ABORT with a Protocol Violation
4502 * error code.
4503 */
4504static sctp_disposition_t sctp_sf_violation_ctsn(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004505 struct net *net,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004506 const struct sctp_endpoint *ep,
4507 const struct sctp_association *asoc,
4508 const sctp_subtype_t type,
4509 void *arg,
4510 sctp_cmd_seq_t *commands)
4511{
wangweidongcb3f8372013-12-23 12:16:50 +08004512 static const char err_str[] = "The cumulative tsn ack beyond the max tsn currently sent:";
Wei Yongjunaecedea2007-08-02 16:57:44 +08004513
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004514 return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004515 sizeof(err_str));
4516}
4517
Vlad Yasevichece25df2007-09-07 16:30:54 -04004518/* Handle protocol violation of an invalid chunk bundling. For example,
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004519 * when we have an association and we receive bundled INIT-ACK, or
Vlad Yasevichece25df2007-09-07 16:30:54 -04004520 * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle"
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004521 * statement from the specs. Additionally, there might be an attacker
Vlad Yasevichece25df2007-09-07 16:30:54 -04004522 * on the path and we may not want to continue this communication.
4523 */
4524static sctp_disposition_t sctp_sf_violation_chunk(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004525 struct net *net,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004526 const struct sctp_endpoint *ep,
4527 const struct sctp_association *asoc,
4528 const sctp_subtype_t type,
4529 void *arg,
4530 sctp_cmd_seq_t *commands)
4531{
wangweidongcb3f8372013-12-23 12:16:50 +08004532 static const char err_str[] = "The following chunk violates protocol:";
Vlad Yasevichece25df2007-09-07 16:30:54 -04004533
4534 if (!asoc)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004535 return sctp_sf_violation(net, ep, asoc, type, arg, commands);
Vlad Yasevichece25df2007-09-07 16:30:54 -04004536
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004537 return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004538 sizeof(err_str));
4539}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004540/***************************************************************************
4541 * These are the state functions for handling primitive (Section 10) events.
4542 ***************************************************************************/
4543/*
4544 * sctp_sf_do_prm_asoc
4545 *
4546 * Section: 10.1 ULP-to-SCTP
4547 * B) Associate
4548 *
4549 * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
4550 * outbound stream count)
4551 * -> association id [,destination transport addr list] [,outbound stream
4552 * count]
4553 *
4554 * This primitive allows the upper layer to initiate an association to a
4555 * specific peer endpoint.
4556 *
4557 * The peer endpoint shall be specified by one of the transport addresses
4558 * which defines the endpoint (see Section 1.4). If the local SCTP
4559 * instance has not been initialized, the ASSOCIATE is considered an
4560 * error.
4561 * [This is not relevant for the kernel implementation since we do all
4562 * initialization at boot time. It we hadn't initialized we wouldn't
4563 * get anywhere near this code.]
4564 *
4565 * An association id, which is a local handle to the SCTP association,
4566 * will be returned on successful establishment of the association. If
4567 * SCTP is not able to open an SCTP association with the peer endpoint,
4568 * an error is returned.
4569 * [In the kernel implementation, the struct sctp_association needs to
4570 * be created BEFORE causing this primitive to run.]
4571 *
4572 * Other association parameters may be returned, including the
4573 * complete destination transport addresses of the peer as well as the
4574 * outbound stream count of the local endpoint. One of the transport
4575 * address from the returned destination addresses will be selected by
4576 * the local endpoint as default primary path for sending SCTP packets
4577 * to this peer. The returned "destination transport addr list" can
4578 * be used by the ULP to change the default primary path or to force
4579 * sending a packet to a specific transport address. [All of this
4580 * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING
4581 * function.]
4582 *
4583 * Mandatory attributes:
4584 *
4585 * o local SCTP instance name - obtained from the INITIALIZE operation.
4586 * [This is the argument asoc.]
4587 * o destination transport addr - specified as one of the transport
4588 * addresses of the peer endpoint with which the association is to be
4589 * established.
4590 * [This is asoc->peer.active_path.]
4591 * o outbound stream count - the number of outbound streams the ULP
4592 * would like to open towards this peer endpoint.
4593 * [BUG: This is not currently implemented.]
4594 * Optional attributes:
4595 *
4596 * None.
4597 *
4598 * The return value is a disposition.
4599 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004600sctp_disposition_t sctp_sf_do_prm_asoc(struct net *net,
4601 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004602 const struct sctp_association *asoc,
4603 const sctp_subtype_t type,
4604 void *arg,
4605 sctp_cmd_seq_t *commands)
4606{
4607 struct sctp_chunk *repl;
wangweidong26ac8e52013-12-23 12:16:51 +08004608 struct sctp_association *my_asoc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004609
4610 /* The comment below says that we enter COOKIE-WAIT AFTER
4611 * sending the INIT, but that doesn't actually work in our
4612 * implementation...
4613 */
4614 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4615 SCTP_STATE(SCTP_STATE_COOKIE_WAIT));
4616
4617 /* RFC 2960 5.1 Normal Establishment of an Association
4618 *
4619 * A) "A" first sends an INIT chunk to "Z". In the INIT, "A"
4620 * must provide its Verification Tag (Tag_A) in the Initiate
4621 * Tag field. Tag_A SHOULD be a random number in the range of
4622 * 1 to 4294967295 (see 5.3.1 for Tag value selection). ...
4623 */
4624
4625 repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0);
4626 if (!repl)
4627 goto nomem;
4628
Daniel Borkmann405426f2013-06-14 18:24:05 +02004629 /* Choose transport for INIT. */
4630 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT,
4631 SCTP_CHUNK(repl));
4632
Linus Torvalds1da177e2005-04-16 15:20:36 -07004633 /* Cast away the const modifier, as we want to just
4634 * rerun it through as a sideffect.
4635 */
Vlad Yasevichab38fb02008-04-12 18:40:06 -07004636 my_asoc = (struct sctp_association *)asoc;
4637 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(my_asoc));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004638
4639 /* After sending the INIT, "A" starts the T1-init timer and
4640 * enters the COOKIE-WAIT state.
4641 */
4642 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
4643 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4644 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
4645 return SCTP_DISPOSITION_CONSUME;
4646
4647nomem:
4648 return SCTP_DISPOSITION_NOMEM;
4649}
4650
4651/*
4652 * Process the SEND primitive.
4653 *
4654 * Section: 10.1 ULP-to-SCTP
4655 * E) Send
4656 *
4657 * Format: SEND(association id, buffer address, byte count [,context]
4658 * [,stream id] [,life time] [,destination transport address]
4659 * [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
4660 * -> result
4661 *
4662 * This is the main method to send user data via SCTP.
4663 *
4664 * Mandatory attributes:
4665 *
4666 * o association id - local handle to the SCTP association
4667 *
4668 * o buffer address - the location where the user message to be
4669 * transmitted is stored;
4670 *
4671 * o byte count - The size of the user data in number of bytes;
4672 *
4673 * Optional attributes:
4674 *
4675 * o context - an optional 32 bit integer that will be carried in the
4676 * sending failure notification to the ULP if the transportation of
4677 * this User Message fails.
4678 *
4679 * o stream id - to indicate which stream to send the data on. If not
4680 * specified, stream 0 will be used.
4681 *
4682 * o life time - specifies the life time of the user data. The user data
4683 * will not be sent by SCTP after the life time expires. This
4684 * parameter can be used to avoid efforts to transmit stale
4685 * user messages. SCTP notifies the ULP if the data cannot be
4686 * initiated to transport (i.e. sent to the destination via SCTP's
4687 * send primitive) within the life time variable. However, the
4688 * user data will be transmitted if SCTP has attempted to transmit a
4689 * chunk before the life time expired.
4690 *
4691 * o destination transport address - specified as one of the destination
4692 * transport addresses of the peer endpoint to which this packet
4693 * should be sent. Whenever possible, SCTP should use this destination
4694 * transport address for sending the packets, instead of the current
4695 * primary path.
4696 *
4697 * o unorder flag - this flag, if present, indicates that the user
4698 * would like the data delivered in an unordered fashion to the peer
4699 * (i.e., the U flag is set to 1 on all DATA chunks carrying this
4700 * message).
4701 *
4702 * o no-bundle flag - instructs SCTP not to bundle this user data with
4703 * other outbound DATA chunks. SCTP MAY still bundle even when
4704 * this flag is present, when faced with network congestion.
4705 *
4706 * o payload protocol-id - A 32 bit unsigned integer that is to be
4707 * passed to the peer indicating the type of payload protocol data
4708 * being transmitted. This value is passed as opaque data by SCTP.
4709 *
4710 * The return value is the disposition.
4711 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004712sctp_disposition_t sctp_sf_do_prm_send(struct net *net,
4713 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004714 const struct sctp_association *asoc,
4715 const sctp_subtype_t type,
4716 void *arg,
4717 sctp_cmd_seq_t *commands)
4718{
Vlad Yasevich9c5c62b2009-08-10 13:51:03 -04004719 struct sctp_datamsg *msg = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004720
Vlad Yasevich9c5c62b2009-08-10 13:51:03 -04004721 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_MSG, SCTP_DATAMSG(msg));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004722 return SCTP_DISPOSITION_CONSUME;
4723}
4724
4725/*
4726 * Process the SHUTDOWN primitive.
4727 *
4728 * Section: 10.1:
4729 * C) Shutdown
4730 *
4731 * Format: SHUTDOWN(association id)
4732 * -> result
4733 *
4734 * Gracefully closes an association. Any locally queued user data
4735 * will be delivered to the peer. The association will be terminated only
4736 * after the peer acknowledges all the SCTP packets sent. A success code
4737 * will be returned on successful termination of the association. If
4738 * attempting to terminate the association results in a failure, an error
4739 * code shall be returned.
4740 *
4741 * Mandatory attributes:
4742 *
4743 * o association id - local handle to the SCTP association
4744 *
4745 * Optional attributes:
4746 *
4747 * None.
4748 *
4749 * The return value is the disposition.
4750 */
4751sctp_disposition_t sctp_sf_do_9_2_prm_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004752 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004753 const struct sctp_endpoint *ep,
4754 const struct sctp_association *asoc,
4755 const sctp_subtype_t type,
4756 void *arg,
4757 sctp_cmd_seq_t *commands)
4758{
4759 int disposition;
4760
4761 /* From 9.2 Shutdown of an Association
4762 * Upon receipt of the SHUTDOWN primitive from its upper
4763 * layer, the endpoint enters SHUTDOWN-PENDING state and
4764 * remains there until all outstanding data has been
4765 * acknowledged by its peer. The endpoint accepts no new data
4766 * from its upper layer, but retransmits data to the far end
4767 * if necessary to fill gaps.
4768 */
4769 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4770 SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING));
4771
Linus Torvalds1da177e2005-04-16 15:20:36 -07004772 disposition = SCTP_DISPOSITION_CONSUME;
4773 if (sctp_outq_is_empty(&asoc->outqueue)) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004774 disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004775 arg, commands);
4776 }
4777 return disposition;
4778}
4779
4780/*
4781 * Process the ABORT primitive.
4782 *
4783 * Section: 10.1:
4784 * C) Abort
4785 *
4786 * Format: Abort(association id [, cause code])
4787 * -> result
4788 *
4789 * Ungracefully closes an association. Any locally queued user data
4790 * will be discarded and an ABORT chunk is sent to the peer. A success code
4791 * will be returned on successful abortion of the association. If
4792 * attempting to abort the association results in a failure, an error
4793 * code shall be returned.
4794 *
4795 * Mandatory attributes:
4796 *
4797 * o association id - local handle to the SCTP association
4798 *
4799 * Optional attributes:
4800 *
4801 * o cause code - reason of the abort to be passed to the peer
4802 *
4803 * None.
4804 *
4805 * The return value is the disposition.
4806 */
4807sctp_disposition_t sctp_sf_do_9_1_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004808 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004809 const struct sctp_endpoint *ep,
4810 const struct sctp_association *asoc,
4811 const sctp_subtype_t type,
4812 void *arg,
4813 sctp_cmd_seq_t *commands)
4814{
4815 /* From 9.1 Abort of an Association
4816 * Upon receipt of the ABORT primitive from its upper
4817 * layer, the endpoint enters CLOSED state and
4818 * discard all outstanding data has been
4819 * acknowledged by its peer. The endpoint accepts no new data
4820 * from its upper layer, but retransmits data to the far end
4821 * if necessary to fill gaps.
4822 */
Sridhar Samudralac164a9b2006-08-22 11:50:39 -07004823 struct sctp_chunk *abort = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004824
Xin Long068d8bd2015-12-29 17:49:25 +08004825 if (abort)
4826 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004827
4828 /* Even if we can't send the ABORT due to low memory delete the
4829 * TCB. This is a departure from our typical NOMEM handling.
4830 */
4831
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07004832 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4833 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004834 /* Delete the established association. */
4835 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08004836 SCTP_PERR(SCTP_ERROR_USER_ABORT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004837
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004838 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
4839 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004840
Marcelo Ricardo Leitner649621e2016-01-08 11:00:54 -02004841 return SCTP_DISPOSITION_ABORT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004842}
4843
4844/* We tried an illegal operation on an association which is closed. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004845sctp_disposition_t sctp_sf_error_closed(struct net *net,
4846 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004847 const struct sctp_association *asoc,
4848 const sctp_subtype_t type,
4849 void *arg,
4850 sctp_cmd_seq_t *commands)
4851{
4852 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL));
4853 return SCTP_DISPOSITION_CONSUME;
4854}
4855
4856/* We tried an illegal operation on an association which is shutting
4857 * down.
4858 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004859sctp_disposition_t sctp_sf_error_shutdown(struct net *net,
4860 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004861 const struct sctp_association *asoc,
4862 const sctp_subtype_t type,
4863 void *arg,
4864 sctp_cmd_seq_t *commands)
4865{
4866 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR,
4867 SCTP_ERROR(-ESHUTDOWN));
4868 return SCTP_DISPOSITION_CONSUME;
4869}
4870
4871/*
4872 * sctp_cookie_wait_prm_shutdown
4873 *
4874 * Section: 4 Note: 2
4875 * Verification Tag:
4876 * Inputs
4877 * (endpoint, asoc)
4878 *
4879 * The RFC does not explicitly address this issue, but is the route through the
4880 * state table when someone issues a shutdown while in COOKIE_WAIT state.
4881 *
4882 * Outputs
4883 * (timers)
4884 */
4885sctp_disposition_t sctp_sf_cookie_wait_prm_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004886 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004887 const struct sctp_endpoint *ep,
4888 const struct sctp_association *asoc,
4889 const sctp_subtype_t type,
4890 void *arg,
4891 sctp_cmd_seq_t *commands)
4892{
4893 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
4894 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4895
4896 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4897 SCTP_STATE(SCTP_STATE_CLOSED));
4898
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004899 SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004900
4901 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
4902
4903 return SCTP_DISPOSITION_DELETE_TCB;
4904}
4905
4906/*
4907 * sctp_cookie_echoed_prm_shutdown
4908 *
4909 * Section: 4 Note: 2
4910 * Verification Tag:
4911 * Inputs
4912 * (endpoint, asoc)
4913 *
4914 * The RFC does not explcitly address this issue, but is the route through the
4915 * state table when someone issues a shutdown while in COOKIE_ECHOED state.
4916 *
4917 * Outputs
4918 * (timers)
4919 */
4920sctp_disposition_t sctp_sf_cookie_echoed_prm_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004921 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004922 const struct sctp_endpoint *ep,
4923 const struct sctp_association *asoc,
4924 const sctp_subtype_t type,
4925 void *arg, sctp_cmd_seq_t *commands)
4926{
4927 /* There is a single T1 timer, so we should be able to use
4928 * common function with the COOKIE-WAIT state.
4929 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004930 return sctp_sf_cookie_wait_prm_shutdown(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004931}
4932
4933/*
4934 * sctp_sf_cookie_wait_prm_abort
4935 *
4936 * Section: 4 Note: 2
4937 * Verification Tag:
4938 * Inputs
4939 * (endpoint, asoc)
4940 *
4941 * The RFC does not explicitly address this issue, but is the route through the
4942 * state table when someone issues an abort while in COOKIE_WAIT state.
4943 *
4944 * Outputs
4945 * (timers)
4946 */
4947sctp_disposition_t sctp_sf_cookie_wait_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004948 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004949 const struct sctp_endpoint *ep,
4950 const struct sctp_association *asoc,
4951 const sctp_subtype_t type,
4952 void *arg,
4953 sctp_cmd_seq_t *commands)
4954{
Sridhar Samudralac164a9b2006-08-22 11:50:39 -07004955 struct sctp_chunk *abort = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004956
4957 /* Stop T1-init timer */
4958 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
4959 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004960
Xin Long068d8bd2015-12-29 17:49:25 +08004961 if (abort)
4962 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004963
4964 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4965 SCTP_STATE(SCTP_STATE_CLOSED));
4966
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004967 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004968
4969 /* Even if we can't send the ABORT due to low memory delete the
4970 * TCB. This is a departure from our typical NOMEM handling.
4971 */
4972
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07004973 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4974 SCTP_ERROR(ECONNREFUSED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004975 /* Delete the established association. */
4976 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08004977 SCTP_PERR(SCTP_ERROR_USER_ABORT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004978
Marcelo Ricardo Leitner649621e2016-01-08 11:00:54 -02004979 return SCTP_DISPOSITION_ABORT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004980}
4981
4982/*
4983 * sctp_sf_cookie_echoed_prm_abort
4984 *
4985 * Section: 4 Note: 3
4986 * Verification Tag:
4987 * Inputs
4988 * (endpoint, asoc)
4989 *
4990 * The RFC does not explcitly address this issue, but is the route through the
4991 * state table when someone issues an abort while in COOKIE_ECHOED state.
4992 *
4993 * Outputs
4994 * (timers)
4995 */
4996sctp_disposition_t sctp_sf_cookie_echoed_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004997 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004998 const struct sctp_endpoint *ep,
4999 const struct sctp_association *asoc,
5000 const sctp_subtype_t type,
5001 void *arg,
5002 sctp_cmd_seq_t *commands)
5003{
5004 /* There is a single T1 timer, so we should be able to use
5005 * common function with the COOKIE-WAIT state.
5006 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005007 return sctp_sf_cookie_wait_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005008}
5009
5010/*
5011 * sctp_sf_shutdown_pending_prm_abort
5012 *
5013 * Inputs
5014 * (endpoint, asoc)
5015 *
5016 * The RFC does not explicitly address this issue, but is the route through the
5017 * state table when someone issues an abort while in SHUTDOWN-PENDING state.
5018 *
5019 * Outputs
5020 * (timers)
5021 */
5022sctp_disposition_t sctp_sf_shutdown_pending_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005023 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005024 const struct sctp_endpoint *ep,
5025 const struct sctp_association *asoc,
5026 const sctp_subtype_t type,
5027 void *arg,
5028 sctp_cmd_seq_t *commands)
5029{
5030 /* Stop the T5-shutdown guard timer. */
5031 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5032 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5033
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005034 return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005035}
5036
5037/*
5038 * sctp_sf_shutdown_sent_prm_abort
5039 *
5040 * Inputs
5041 * (endpoint, asoc)
5042 *
5043 * The RFC does not explicitly address this issue, but is the route through the
5044 * state table when someone issues an abort while in SHUTDOWN-SENT state.
5045 *
5046 * Outputs
5047 * (timers)
5048 */
5049sctp_disposition_t sctp_sf_shutdown_sent_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005050 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005051 const struct sctp_endpoint *ep,
5052 const struct sctp_association *asoc,
5053 const sctp_subtype_t type,
5054 void *arg,
5055 sctp_cmd_seq_t *commands)
5056{
5057 /* Stop the T2-shutdown timer. */
5058 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5059 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5060
5061 /* Stop the T5-shutdown guard timer. */
5062 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5063 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5064
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005065 return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005066}
5067
5068/*
5069 * sctp_sf_cookie_echoed_prm_abort
5070 *
5071 * Inputs
5072 * (endpoint, asoc)
5073 *
5074 * The RFC does not explcitly address this issue, but is the route through the
5075 * state table when someone issues an abort while in COOKIE_ECHOED state.
5076 *
5077 * Outputs
5078 * (timers)
5079 */
5080sctp_disposition_t sctp_sf_shutdown_ack_sent_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005081 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005082 const struct sctp_endpoint *ep,
5083 const struct sctp_association *asoc,
5084 const sctp_subtype_t type,
5085 void *arg,
5086 sctp_cmd_seq_t *commands)
5087{
5088 /* The same T2 timer, so we should be able to use
5089 * common function with the SHUTDOWN-SENT state.
5090 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005091 return sctp_sf_shutdown_sent_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005092}
5093
5094/*
5095 * Process the REQUESTHEARTBEAT primitive
5096 *
5097 * 10.1 ULP-to-SCTP
5098 * J) Request Heartbeat
5099 *
5100 * Format: REQUESTHEARTBEAT(association id, destination transport address)
5101 *
5102 * -> result
5103 *
5104 * Instructs the local endpoint to perform a HeartBeat on the specified
5105 * destination transport address of the given association. The returned
5106 * result should indicate whether the transmission of the HEARTBEAT
5107 * chunk to the destination address is successful.
5108 *
5109 * Mandatory attributes:
5110 *
5111 * o association id - local handle to the SCTP association
5112 *
5113 * o destination transport address - the transport address of the
5114 * association on which a heartbeat should be issued.
5115 */
5116sctp_disposition_t sctp_sf_do_prm_requestheartbeat(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005117 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005118 const struct sctp_endpoint *ep,
5119 const struct sctp_association *asoc,
5120 const sctp_subtype_t type,
5121 void *arg,
5122 sctp_cmd_seq_t *commands)
5123{
Vlad Yasevichfb785252007-03-19 17:02:03 -07005124 if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type,
5125 (struct sctp_transport *)arg, commands))
5126 return SCTP_DISPOSITION_NOMEM;
5127
5128 /*
5129 * RFC 2960 (bis), section 8.3
5130 *
5131 * D) Request an on-demand HEARTBEAT on a specific destination
5132 * transport address of a given association.
5133 *
5134 * The endpoint should increment the respective error counter of
5135 * the destination transport address each time a HEARTBEAT is sent
5136 * to that address and not acknowledged within one RTO.
5137 *
5138 */
Vlad Yasevich7e990132009-03-02 09:46:14 +00005139 sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT,
Vlad Yasevichfb785252007-03-19 17:02:03 -07005140 SCTP_TRANSPORT(arg));
5141 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005142}
5143
5144/*
5145 * ADDIP Section 4.1 ASCONF Chunk Procedures
5146 * When an endpoint has an ASCONF signaled change to be sent to the
5147 * remote endpoint it should do A1 to A9
5148 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005149sctp_disposition_t sctp_sf_do_prm_asconf(struct net *net,
5150 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005151 const struct sctp_association *asoc,
5152 const sctp_subtype_t type,
5153 void *arg,
5154 sctp_cmd_seq_t *commands)
5155{
5156 struct sctp_chunk *chunk = arg;
5157
5158 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk));
5159 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
5160 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
5161 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk));
5162 return SCTP_DISPOSITION_CONSUME;
5163}
5164
5165/*
5166 * Ignore the primitive event
5167 *
5168 * The return value is the disposition of the primitive.
5169 */
5170sctp_disposition_t sctp_sf_ignore_primitive(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005171 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005172 const struct sctp_endpoint *ep,
5173 const struct sctp_association *asoc,
5174 const sctp_subtype_t type,
5175 void *arg,
5176 sctp_cmd_seq_t *commands)
5177{
Daniel Borkmannbb333812013-06-28 19:49:40 +02005178 pr_debug("%s: primitive type:%d is ignored\n", __func__,
5179 type.primitive);
5180
Linus Torvalds1da177e2005-04-16 15:20:36 -07005181 return SCTP_DISPOSITION_DISCARD;
5182}
5183
5184/***************************************************************************
5185 * These are the state functions for the OTHER events.
5186 ***************************************************************************/
5187
5188/*
Wei Yongjune1cdd552011-04-17 17:29:03 +00005189 * When the SCTP stack has no more user data to send or retransmit, this
5190 * notification is given to the user. Also, at the time when a user app
5191 * subscribes to this event, if there is no data to be sent or
5192 * retransmit, the stack will immediately send up this notification.
5193 */
5194sctp_disposition_t sctp_sf_do_no_pending_tsn(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005195 struct net *net,
Wei Yongjune1cdd552011-04-17 17:29:03 +00005196 const struct sctp_endpoint *ep,
5197 const struct sctp_association *asoc,
5198 const sctp_subtype_t type,
5199 void *arg,
5200 sctp_cmd_seq_t *commands)
5201{
5202 struct sctp_ulpevent *event;
5203
5204 event = sctp_ulpevent_make_sender_dry_event(asoc, GFP_ATOMIC);
5205 if (!event)
5206 return SCTP_DISPOSITION_NOMEM;
5207
5208 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event));
5209
5210 return SCTP_DISPOSITION_CONSUME;
5211}
5212
5213/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07005214 * Start the shutdown negotiation.
5215 *
5216 * From Section 9.2:
5217 * Once all its outstanding data has been acknowledged, the endpoint
5218 * shall send a SHUTDOWN chunk to its peer including in the Cumulative
5219 * TSN Ack field the last sequential TSN it has received from the peer.
5220 * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT
5221 * state. If the timer expires, the endpoint must re-send the SHUTDOWN
5222 * with the updated last sequential TSN received from its peer.
5223 *
5224 * The return value is the disposition.
5225 */
5226sctp_disposition_t sctp_sf_do_9_2_start_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005227 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005228 const struct sctp_endpoint *ep,
5229 const struct sctp_association *asoc,
5230 const sctp_subtype_t type,
5231 void *arg,
5232 sctp_cmd_seq_t *commands)
5233{
5234 struct sctp_chunk *reply;
5235
5236 /* Once all its outstanding data has been acknowledged, the
5237 * endpoint shall send a SHUTDOWN chunk to its peer including
5238 * in the Cumulative TSN Ack field the last sequential TSN it
5239 * has received from the peer.
5240 */
5241 reply = sctp_make_shutdown(asoc, NULL);
5242 if (!reply)
5243 goto nomem;
5244
5245 /* Set the transport for the SHUTDOWN chunk and the timeout for the
5246 * T2-shutdown timer.
5247 */
5248 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
5249
5250 /* It shall then start the T2-shutdown timer */
5251 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
5252 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5253
Wei Yongjun536428a2008-09-05 08:55:26 +08005254 /* RFC 4960 Section 9.2
5255 * The sender of the SHUTDOWN MAY also start an overall guard timer
5256 * 'T5-shutdown-guard' to bound the overall time for shutdown sequence.
5257 */
Thomas Graff8d96052011-07-07 00:28:35 +00005258 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
Wei Yongjun536428a2008-09-05 08:55:26 +08005259 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5260
Neil Horman9f70f462013-12-10 06:48:15 -05005261 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE])
Linus Torvalds1da177e2005-04-16 15:20:36 -07005262 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5263 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
5264
5265 /* and enter the SHUTDOWN-SENT state. */
5266 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
5267 SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT));
5268
5269 /* sctp-implguide 2.10 Issues with Heartbeating and failover
5270 *
5271 * HEARTBEAT ... is discontinued after sending either SHUTDOWN
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09005272 * or SHUTDOWN-ACK.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005273 */
5274 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL());
5275
5276 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
5277
5278 return SCTP_DISPOSITION_CONSUME;
5279
5280nomem:
5281 return SCTP_DISPOSITION_NOMEM;
5282}
5283
5284/*
5285 * Generate a SHUTDOWN ACK now that everything is SACK'd.
5286 *
5287 * From Section 9.2:
5288 *
5289 * If it has no more outstanding DATA chunks, the SHUTDOWN receiver
5290 * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own,
5291 * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the
5292 * endpoint must re-send the SHUTDOWN ACK.
5293 *
5294 * The return value is the disposition.
5295 */
5296sctp_disposition_t sctp_sf_do_9_2_shutdown_ack(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005297 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005298 const struct sctp_endpoint *ep,
5299 const struct sctp_association *asoc,
5300 const sctp_subtype_t type,
5301 void *arg,
5302 sctp_cmd_seq_t *commands)
5303{
5304 struct sctp_chunk *chunk = (struct sctp_chunk *) arg;
5305 struct sctp_chunk *reply;
5306
5307 /* There are 2 ways of getting here:
5308 * 1) called in response to a SHUTDOWN chunk
5309 * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued.
5310 *
5311 * For the case (2), the arg parameter is set to NULL. We need
5312 * to check that we have a chunk before accessing it's fields.
5313 */
5314 if (chunk) {
5315 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005316 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005317
5318 /* Make sure that the SHUTDOWN chunk has a valid length. */
5319 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005320 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005321 commands);
5322 }
5323
5324 /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver
5325 * shall send a SHUTDOWN ACK ...
5326 */
5327 reply = sctp_make_shutdown_ack(asoc, chunk);
5328 if (!reply)
5329 goto nomem;
5330
5331 /* Set the transport for the SHUTDOWN ACK chunk and the timeout for
5332 * the T2-shutdown timer.
5333 */
5334 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
5335
5336 /* and start/restart a T2-shutdown timer of its own, */
5337 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
5338 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5339
Neil Horman9f70f462013-12-10 06:48:15 -05005340 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE])
Linus Torvalds1da177e2005-04-16 15:20:36 -07005341 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5342 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
5343
5344 /* Enter the SHUTDOWN-ACK-SENT state. */
5345 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
5346 SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT));
5347
5348 /* sctp-implguide 2.10 Issues with Heartbeating and failover
5349 *
5350 * HEARTBEAT ... is discontinued after sending either SHUTDOWN
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09005351 * or SHUTDOWN-ACK.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005352 */
5353 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL());
5354
5355 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
5356
5357 return SCTP_DISPOSITION_CONSUME;
5358
5359nomem:
5360 return SCTP_DISPOSITION_NOMEM;
5361}
5362
5363/*
5364 * Ignore the event defined as other
5365 *
5366 * The return value is the disposition of the event.
5367 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005368sctp_disposition_t sctp_sf_ignore_other(struct net *net,
5369 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005370 const struct sctp_association *asoc,
5371 const sctp_subtype_t type,
5372 void *arg,
5373 sctp_cmd_seq_t *commands)
5374{
Daniel Borkmannbb333812013-06-28 19:49:40 +02005375 pr_debug("%s: the event other type:%d is ignored\n",
5376 __func__, type.other);
5377
Linus Torvalds1da177e2005-04-16 15:20:36 -07005378 return SCTP_DISPOSITION_DISCARD;
5379}
5380
5381/************************************************************
5382 * These are the state functions for handling timeout events.
5383 ************************************************************/
5384
5385/*
5386 * RTX Timeout
5387 *
5388 * Section: 6.3.3 Handle T3-rtx Expiration
5389 *
5390 * Whenever the retransmission timer T3-rtx expires for a destination
5391 * address, do the following:
5392 * [See below]
5393 *
5394 * The return value is the disposition of the chunk.
5395 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005396sctp_disposition_t sctp_sf_do_6_3_3_rtx(struct net *net,
5397 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005398 const struct sctp_association *asoc,
5399 const sctp_subtype_t type,
5400 void *arg,
5401 sctp_cmd_seq_t *commands)
5402{
5403 struct sctp_transport *transport = arg;
5404
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005405 SCTP_INC_STATS(net, SCTP_MIB_T3_RTX_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005406
Linus Torvalds1da177e2005-04-16 15:20:36 -07005407 if (asoc->overall_error_count >= asoc->max_retrans) {
lucien8a0d19c2015-12-05 15:35:36 +08005408 if (asoc->peer.zero_window_announced &&
5409 asoc->state == SCTP_STATE_SHUTDOWN_PENDING) {
Thomas Graff8d96052011-07-07 00:28:35 +00005410 /*
5411 * We are here likely because the receiver had its rwnd
5412 * closed for a while and we have not been able to
5413 * transmit the locally queued data within the maximum
5414 * retransmission attempts limit. Start the T5
5415 * shutdown guard timer to give the receiver one last
5416 * chance and some additional time to recover before
5417 * aborting.
5418 */
5419 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START_ONCE,
5420 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5421 } else {
5422 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5423 SCTP_ERROR(ETIMEDOUT));
5424 /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
5425 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
5426 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005427 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5428 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Thomas Graff8d96052011-07-07 00:28:35 +00005429 return SCTP_DISPOSITION_DELETE_TCB;
5430 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005431 }
5432
5433 /* E1) For the destination address for which the timer
5434 * expires, adjust its ssthresh with rules defined in Section
5435 * 7.2.3 and set the cwnd <- MTU.
5436 */
5437
5438 /* E2) For the destination address for which the timer
5439 * expires, set RTO <- RTO * 2 ("back off the timer"). The
5440 * maximum value discussed in rule C7 above (RTO.max) may be
5441 * used to provide an upper bound to this doubling operation.
5442 */
5443
5444 /* E3) Determine how many of the earliest (i.e., lowest TSN)
5445 * outstanding DATA chunks for the address for which the
5446 * T3-rtx has expired will fit into a single packet, subject
5447 * to the MTU constraint for the path corresponding to the
5448 * destination transport address to which the retransmission
5449 * is being sent (this may be different from the address for
5450 * which the timer expires [see Section 6.4]). Call this
5451 * value K. Bundle and retransmit those K DATA chunks in a
5452 * single packet to the destination endpoint.
5453 *
5454 * Note: Any DATA chunks that were sent to the address for
5455 * which the T3-rtx timer expired but did not fit in one MTU
5456 * (rule E3 above), should be marked for retransmission and
5457 * sent as soon as cwnd allows (normally when a SACK arrives).
5458 */
5459
Linus Torvalds1da177e2005-04-16 15:20:36 -07005460 /* Do some failure management (Section 8.2). */
5461 sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport));
5462
Vlad Yasevich1845a572007-02-21 02:06:19 -08005463 /* NB: Rules E4 and F1 are implicit in R1. */
5464 sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport));
5465
Linus Torvalds1da177e2005-04-16 15:20:36 -07005466 return SCTP_DISPOSITION_CONSUME;
5467}
5468
5469/*
5470 * Generate delayed SACK on timeout
5471 *
5472 * Section: 6.2 Acknowledgement on Reception of DATA Chunks
5473 *
5474 * The guidelines on delayed acknowledgement algorithm specified in
5475 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an
5476 * acknowledgement SHOULD be generated for at least every second packet
5477 * (not every second DATA chunk) received, and SHOULD be generated
5478 * within 200 ms of the arrival of any unacknowledged DATA chunk. In
5479 * some situations it may be beneficial for an SCTP transmitter to be
5480 * more conservative than the algorithms detailed in this document
5481 * allow. However, an SCTP transmitter MUST NOT be more aggressive than
5482 * the following algorithms allow.
5483 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005484sctp_disposition_t sctp_sf_do_6_2_sack(struct net *net,
5485 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005486 const struct sctp_association *asoc,
5487 const sctp_subtype_t type,
5488 void *arg,
5489 sctp_cmd_seq_t *commands)
5490{
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005491 SCTP_INC_STATS(net, SCTP_MIB_DELAY_SACK_EXPIREDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005492 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
5493 return SCTP_DISPOSITION_CONSUME;
5494}
5495
5496/*
Frank Filz3f7a87d2005-06-20 13:14:57 -07005497 * sctp_sf_t1_init_timer_expire
Linus Torvalds1da177e2005-04-16 15:20:36 -07005498 *
5499 * Section: 4 Note: 2
5500 * Verification Tag:
5501 * Inputs
5502 * (endpoint, asoc)
5503 *
5504 * RFC 2960 Section 4 Notes
5505 * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT
5506 * and re-start the T1-init timer without changing state. This MUST
5507 * be repeated up to 'Max.Init.Retransmits' times. After that, the
5508 * endpoint MUST abort the initialization process and report the
5509 * error to SCTP user.
5510 *
Frank Filz3f7a87d2005-06-20 13:14:57 -07005511 * Outputs
5512 * (timers, events)
5513 *
5514 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005515sctp_disposition_t sctp_sf_t1_init_timer_expire(struct net *net,
5516 const struct sctp_endpoint *ep,
Frank Filz3f7a87d2005-06-20 13:14:57 -07005517 const struct sctp_association *asoc,
5518 const sctp_subtype_t type,
5519 void *arg,
5520 sctp_cmd_seq_t *commands)
5521{
5522 struct sctp_chunk *repl = NULL;
5523 struct sctp_bind_addr *bp;
5524 int attempts = asoc->init_err_counter + 1;
5525
Daniel Borkmannbb333812013-06-28 19:49:40 +02005526 pr_debug("%s: timer T1 expired (INIT)\n", __func__);
5527
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005528 SCTP_INC_STATS(net, SCTP_MIB_T1_INIT_EXPIREDS);
Frank Filz3f7a87d2005-06-20 13:14:57 -07005529
Vlad Yasevich81845c22006-01-30 15:59:54 -08005530 if (attempts <= asoc->max_init_attempts) {
Frank Filz3f7a87d2005-06-20 13:14:57 -07005531 bp = (struct sctp_bind_addr *) &asoc->base.bind_addr;
5532 repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0);
5533 if (!repl)
5534 return SCTP_DISPOSITION_NOMEM;
5535
5536 /* Choose transport for INIT. */
5537 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT,
5538 SCTP_CHUNK(repl));
5539
5540 /* Issue a sideeffect to do the needed accounting. */
5541 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART,
5542 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
5543
5544 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
5545 } else {
Daniel Borkmannbb333812013-06-28 19:49:40 +02005546 pr_debug("%s: giving up on INIT, attempts:%d "
5547 "max_init_attempts:%d\n", __func__, attempts,
5548 asoc->max_init_attempts);
5549
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005550 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5551 SCTP_ERROR(ETIMEDOUT));
Frank Filz3f7a87d2005-06-20 13:14:57 -07005552 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08005553 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Frank Filz3f7a87d2005-06-20 13:14:57 -07005554 return SCTP_DISPOSITION_DELETE_TCB;
5555 }
5556
5557 return SCTP_DISPOSITION_CONSUME;
5558}
5559
5560/*
5561 * sctp_sf_t1_cookie_timer_expire
5562 *
5563 * Section: 4 Note: 2
5564 * Verification Tag:
5565 * Inputs
5566 * (endpoint, asoc)
5567 *
5568 * RFC 2960 Section 4 Notes
5569 * 3) If the T1-cookie timer expires, the endpoint MUST retransmit
Linus Torvalds1da177e2005-04-16 15:20:36 -07005570 * COOKIE ECHO and re-start the T1-cookie timer without changing
5571 * state. This MUST be repeated up to 'Max.Init.Retransmits' times.
5572 * After that, the endpoint MUST abort the initialization process and
5573 * report the error to SCTP user.
5574 *
5575 * Outputs
5576 * (timers, events)
5577 *
5578 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005579sctp_disposition_t sctp_sf_t1_cookie_timer_expire(struct net *net,
5580 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005581 const struct sctp_association *asoc,
5582 const sctp_subtype_t type,
5583 void *arg,
5584 sctp_cmd_seq_t *commands)
5585{
Frank Filz3f7a87d2005-06-20 13:14:57 -07005586 struct sctp_chunk *repl = NULL;
5587 int attempts = asoc->init_err_counter + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005588
Daniel Borkmannbb333812013-06-28 19:49:40 +02005589 pr_debug("%s: timer T1 expired (COOKIE-ECHO)\n", __func__);
5590
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005591 SCTP_INC_STATS(net, SCTP_MIB_T1_COOKIE_EXPIREDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005592
Vlad Yasevich81845c22006-01-30 15:59:54 -08005593 if (attempts <= asoc->max_init_attempts) {
Frank Filz3f7a87d2005-06-20 13:14:57 -07005594 repl = sctp_make_cookie_echo(asoc, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005595 if (!repl)
Frank Filz3f7a87d2005-06-20 13:14:57 -07005596 return SCTP_DISPOSITION_NOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005597
Vlad Yasevich96cd0d32008-09-08 14:00:26 -04005598 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT,
5599 SCTP_CHUNK(repl));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005600 /* Issue a sideeffect to do the needed accounting. */
Frank Filz3f7a87d2005-06-20 13:14:57 -07005601 sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART,
5602 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
5603
Linus Torvalds1da177e2005-04-16 15:20:36 -07005604 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
5605 } else {
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005606 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5607 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005608 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08005609 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005610 return SCTP_DISPOSITION_DELETE_TCB;
5611 }
5612
5613 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005614}
5615
5616/* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN
5617 * with the updated last sequential TSN received from its peer.
5618 *
5619 * An endpoint should limit the number of retransmissions of the
5620 * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'.
5621 * If this threshold is exceeded the endpoint should destroy the TCB and
5622 * MUST report the peer endpoint unreachable to the upper layer (and
5623 * thus the association enters the CLOSED state). The reception of any
5624 * packet from its peer (i.e. as the peer sends all of its queued DATA
5625 * chunks) should clear the endpoint's retransmission count and restart
5626 * the T2-Shutdown timer, giving its peer ample opportunity to transmit
5627 * all of its queued DATA chunks that have not yet been sent.
5628 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005629sctp_disposition_t sctp_sf_t2_timer_expire(struct net *net,
5630 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005631 const struct sctp_association *asoc,
5632 const sctp_subtype_t type,
5633 void *arg,
5634 sctp_cmd_seq_t *commands)
5635{
5636 struct sctp_chunk *reply = NULL;
5637
Daniel Borkmannbb333812013-06-28 19:49:40 +02005638 pr_debug("%s: timer T2 expired\n", __func__);
5639
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005640 SCTP_INC_STATS(net, SCTP_MIB_T2_SHUTDOWN_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005641
Neil Horman58fbbed2008-02-29 11:40:56 -08005642 ((struct sctp_association *)asoc)->shutdown_retries++;
5643
Linus Torvalds1da177e2005-04-16 15:20:36 -07005644 if (asoc->overall_error_count >= asoc->max_retrans) {
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005645 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5646 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005647 /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
5648 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08005649 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005650 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5651 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005652 return SCTP_DISPOSITION_DELETE_TCB;
5653 }
5654
5655 switch (asoc->state) {
5656 case SCTP_STATE_SHUTDOWN_SENT:
5657 reply = sctp_make_shutdown(asoc, NULL);
5658 break;
5659
5660 case SCTP_STATE_SHUTDOWN_ACK_SENT:
5661 reply = sctp_make_shutdown_ack(asoc, NULL);
5662 break;
5663
5664 default:
5665 BUG();
5666 break;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07005667 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005668
5669 if (!reply)
5670 goto nomem;
5671
Wei Yongjun6345b192009-04-26 23:13:35 +08005672 /* Do some failure management (Section 8.2).
5673 * If we remove the transport an SHUTDOWN was last sent to, don't
5674 * do failure management.
5675 */
5676 if (asoc->shutdown_last_sent_to)
5677 sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE,
5678 SCTP_TRANSPORT(asoc->shutdown_last_sent_to));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005679
5680 /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for
5681 * the T2-shutdown timer.
5682 */
5683 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
5684
5685 /* Restart the T2-shutdown timer. */
5686 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
5687 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5688 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
5689 return SCTP_DISPOSITION_CONSUME;
5690
5691nomem:
5692 return SCTP_DISPOSITION_NOMEM;
5693}
5694
5695/*
5696 * ADDIP Section 4.1 ASCONF CHunk Procedures
5697 * If the T4 RTO timer expires the endpoint should do B1 to B5
5698 */
5699sctp_disposition_t sctp_sf_t4_timer_expire(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005700 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005701 const struct sctp_endpoint *ep,
5702 const struct sctp_association *asoc,
5703 const sctp_subtype_t type,
5704 void *arg,
5705 sctp_cmd_seq_t *commands)
5706{
5707 struct sctp_chunk *chunk = asoc->addip_last_asconf;
5708 struct sctp_transport *transport = chunk->transport;
5709
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005710 SCTP_INC_STATS(net, SCTP_MIB_T4_RTO_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005711
Linus Torvalds1da177e2005-04-16 15:20:36 -07005712 /* ADDIP 4.1 B1) Increment the error counters and perform path failure
5713 * detection on the appropriate destination address as defined in
5714 * RFC2960 [5] section 8.1 and 8.2.
5715 */
Wei Yongjun10a43ce2009-04-26 23:14:42 +08005716 if (transport)
5717 sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE,
5718 SCTP_TRANSPORT(transport));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005719
5720 /* Reconfig T4 timer and transport. */
5721 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk));
5722
5723 /* ADDIP 4.1 B2) Increment the association error counters and perform
5724 * endpoint failure detection on the association as defined in
5725 * RFC2960 [5] section 8.1 and 8.2.
5726 * association error counter is incremented in SCTP_CMD_STRIKE.
5727 */
5728 if (asoc->overall_error_count >= asoc->max_retrans) {
5729 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5730 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005731 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5732 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005733 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08005734 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005735 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5736 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005737 return SCTP_DISPOSITION_ABORT;
5738 }
5739
5740 /* ADDIP 4.1 B3) Back-off the destination address RTO value to which
5741 * the ASCONF chunk was sent by doubling the RTO timer value.
5742 * This is done in SCTP_CMD_STRIKE.
5743 */
5744
5745 /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible
5746 * choose an alternate destination address (please refer to RFC2960
5747 * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09005748 * chunk, it MUST be the same (including its serial number) as the last
Linus Torvalds1da177e2005-04-16 15:20:36 -07005749 * ASCONF sent.
5750 */
5751 sctp_chunk_hold(asoc->addip_last_asconf);
5752 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
5753 SCTP_CHUNK(asoc->addip_last_asconf));
5754
5755 /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different
5756 * destination is selected, then the RTO used will be that of the new
5757 * destination address.
5758 */
5759 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
5760 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
5761
5762 return SCTP_DISPOSITION_CONSUME;
5763}
5764
5765/* sctpimpguide-05 Section 2.12.2
5766 * The sender of the SHUTDOWN MAY also start an overall guard timer
5767 * 'T5-shutdown-guard' to bound the overall time for shutdown sequence.
5768 * At the expiration of this timer the sender SHOULD abort the association
5769 * by sending an ABORT chunk.
5770 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005771sctp_disposition_t sctp_sf_t5_timer_expire(struct net *net,
5772 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005773 const struct sctp_association *asoc,
5774 const sctp_subtype_t type,
5775 void *arg,
5776 sctp_cmd_seq_t *commands)
5777{
5778 struct sctp_chunk *reply = NULL;
5779
Daniel Borkmannbb333812013-06-28 19:49:40 +02005780 pr_debug("%s: timer T5 expired\n", __func__);
5781
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005782 SCTP_INC_STATS(net, SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005783
5784 reply = sctp_make_abort(asoc, NULL, 0);
5785 if (!reply)
5786 goto nomem;
5787
5788 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005789 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5790 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005791 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08005792 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005793
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005794 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5795 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Vlad Yasevicha1080a82008-10-09 14:33:26 -07005796
Linus Torvalds1da177e2005-04-16 15:20:36 -07005797 return SCTP_DISPOSITION_DELETE_TCB;
5798nomem:
5799 return SCTP_DISPOSITION_NOMEM;
5800}
5801
5802/* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires,
5803 * the association is automatically closed by starting the shutdown process.
5804 * The work that needs to be done is same as when SHUTDOWN is initiated by
5805 * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown().
5806 */
5807sctp_disposition_t sctp_sf_autoclose_timer_expire(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005808 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005809 const struct sctp_endpoint *ep,
5810 const struct sctp_association *asoc,
5811 const sctp_subtype_t type,
5812 void *arg,
5813 sctp_cmd_seq_t *commands)
5814{
5815 int disposition;
5816
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005817 SCTP_INC_STATS(net, SCTP_MIB_AUTOCLOSE_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005818
Linus Torvalds1da177e2005-04-16 15:20:36 -07005819 /* From 9.2 Shutdown of an Association
5820 * Upon receipt of the SHUTDOWN primitive from its upper
5821 * layer, the endpoint enters SHUTDOWN-PENDING state and
5822 * remains there until all outstanding data has been
5823 * acknowledged by its peer. The endpoint accepts no new data
5824 * from its upper layer, but retransmits data to the far end
5825 * if necessary to fill gaps.
5826 */
5827 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
5828 SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING));
5829
Linus Torvalds1da177e2005-04-16 15:20:36 -07005830 disposition = SCTP_DISPOSITION_CONSUME;
5831 if (sctp_outq_is_empty(&asoc->outqueue)) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005832 disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005833 arg, commands);
5834 }
5835 return disposition;
5836}
5837
5838/*****************************************************************************
5839 * These are sa state functions which could apply to all types of events.
5840 ****************************************************************************/
5841
5842/*
5843 * This table entry is not implemented.
5844 *
5845 * Inputs
5846 * (endpoint, asoc, chunk)
5847 *
5848 * The return value is the disposition of the chunk.
5849 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005850sctp_disposition_t sctp_sf_not_impl(struct net *net,
5851 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005852 const struct sctp_association *asoc,
5853 const sctp_subtype_t type,
5854 void *arg,
5855 sctp_cmd_seq_t *commands)
5856{
5857 return SCTP_DISPOSITION_NOT_IMPL;
5858}
5859
5860/*
5861 * This table entry represents a bug.
5862 *
5863 * Inputs
5864 * (endpoint, asoc, chunk)
5865 *
5866 * The return value is the disposition of the chunk.
5867 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005868sctp_disposition_t sctp_sf_bug(struct net *net,
5869 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005870 const struct sctp_association *asoc,
5871 const sctp_subtype_t type,
5872 void *arg,
5873 sctp_cmd_seq_t *commands)
5874{
5875 return SCTP_DISPOSITION_BUG;
5876}
5877
5878/*
5879 * This table entry represents the firing of a timer in the wrong state.
5880 * Since timer deletion cannot be guaranteed a timer 'may' end up firing
5881 * when the association is in the wrong state. This event should
5882 * be ignored, so as to prevent any rearming of the timer.
5883 *
5884 * Inputs
5885 * (endpoint, asoc, chunk)
5886 *
5887 * The return value is the disposition of the chunk.
5888 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005889sctp_disposition_t sctp_sf_timer_ignore(struct net *net,
5890 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005891 const struct sctp_association *asoc,
5892 const sctp_subtype_t type,
5893 void *arg,
5894 sctp_cmd_seq_t *commands)
5895{
Daniel Borkmannbb333812013-06-28 19:49:40 +02005896 pr_debug("%s: timer %d ignored\n", __func__, type.chunk);
5897
Linus Torvalds1da177e2005-04-16 15:20:36 -07005898 return SCTP_DISPOSITION_CONSUME;
5899}
5900
5901/********************************************************************
5902 * 2nd Level Abstractions
5903 ********************************************************************/
5904
5905/* Pull the SACK chunk based on the SACK header. */
5906static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk)
5907{
5908 struct sctp_sackhdr *sack;
5909 unsigned int len;
5910 __u16 num_blocks;
5911 __u16 num_dup_tsns;
5912
5913 /* Protect ourselves from reading too far into
5914 * the skb from a bogus sender.
5915 */
5916 sack = (struct sctp_sackhdr *) chunk->skb->data;
5917
5918 num_blocks = ntohs(sack->num_gap_ack_blocks);
5919 num_dup_tsns = ntohs(sack->num_dup_tsns);
5920 len = sizeof(struct sctp_sackhdr);
5921 len += (num_blocks + num_dup_tsns) * sizeof(__u32);
5922 if (len > chunk->skb->len)
5923 return NULL;
5924
5925 skb_pull(chunk->skb, len);
5926
5927 return sack;
5928}
5929
5930/* Create an ABORT packet to be sent as a response, with the specified
5931 * error causes.
5932 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005933static struct sctp_packet *sctp_abort_pkt_new(struct net *net,
5934 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005935 const struct sctp_association *asoc,
5936 struct sctp_chunk *chunk,
5937 const void *payload,
5938 size_t paylen)
5939{
5940 struct sctp_packet *packet;
5941 struct sctp_chunk *abort;
5942
Eric W. Biederman2ce95502012-08-06 08:43:06 +00005943 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005944
5945 if (packet) {
5946 /* Make an ABORT.
5947 * The T bit will be set if the asoc is NULL.
5948 */
5949 abort = sctp_make_abort(asoc, chunk, paylen);
5950 if (!abort) {
5951 sctp_ootb_pkt_free(packet);
5952 return NULL;
5953 }
Jerome Forissier047a2422005-04-28 11:58:43 -07005954
5955 /* Reflect vtag if T-Bit is set */
5956 if (sctp_test_T_bit(abort))
5957 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
5958
Linus Torvalds1da177e2005-04-16 15:20:36 -07005959 /* Add specified error causes, i.e., payload, to the
5960 * end of the chunk.
5961 */
5962 sctp_addto_chunk(abort, paylen, payload);
5963
5964 /* Set the skb to the belonging sock for accounting. */
5965 abort->skb->sk = ep->base.sk;
5966
5967 sctp_packet_append_chunk(packet, abort);
5968
5969 }
5970
5971 return packet;
5972}
5973
5974/* Allocate a packet for responding in the OOTB conditions. */
Eric W. Biederman2ce95502012-08-06 08:43:06 +00005975static struct sctp_packet *sctp_ootb_pkt_new(struct net *net,
5976 const struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005977 const struct sctp_chunk *chunk)
5978{
5979 struct sctp_packet *packet;
5980 struct sctp_transport *transport;
5981 __u16 sport;
5982 __u16 dport;
5983 __u32 vtag;
5984
5985 /* Get the source and destination port from the inbound packet. */
5986 sport = ntohs(chunk->sctp_hdr->dest);
5987 dport = ntohs(chunk->sctp_hdr->source);
5988
5989 /* The V-tag is going to be the same as the inbound packet if no
5990 * association exists, otherwise, use the peer's vtag.
5991 */
5992 if (asoc) {
Wei Yongjun02c4e122007-08-31 10:03:58 +08005993 /* Special case the INIT-ACK as there is no peer's vtag
5994 * yet.
5995 */
wangweidongcb3f8372013-12-23 12:16:50 +08005996 switch (chunk->chunk_hdr->type) {
Wei Yongjun02c4e122007-08-31 10:03:58 +08005997 case SCTP_CID_INIT_ACK:
5998 {
5999 sctp_initack_chunk_t *initack;
6000
6001 initack = (sctp_initack_chunk_t *)chunk->chunk_hdr;
6002 vtag = ntohl(initack->init_hdr.init_tag);
6003 break;
6004 }
6005 default:
6006 vtag = asoc->peer.i.init_tag;
6007 break;
6008 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07006009 } else {
6010 /* Special case the INIT and stale COOKIE_ECHO as there is no
6011 * vtag yet.
6012 */
wangweidongcb3f8372013-12-23 12:16:50 +08006013 switch (chunk->chunk_hdr->type) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07006014 case SCTP_CID_INIT:
6015 {
6016 sctp_init_chunk_t *init;
6017
6018 init = (sctp_init_chunk_t *)chunk->chunk_hdr;
6019 vtag = ntohl(init->init_hdr.init_tag);
6020 break;
6021 }
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09006022 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -07006023 vtag = ntohl(chunk->sctp_hdr->vtag);
6024 break;
6025 }
6026 }
6027
6028 /* Make a transport for the bucket, Eliza... */
Eric W. Biederman89bf3452012-08-07 07:26:14 +00006029 transport = sctp_transport_new(net, sctp_source(chunk), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006030 if (!transport)
6031 goto nomem;
6032
6033 /* Cache a route for the transport with the chunk's destination as
6034 * the source address.
6035 */
Al Viro16b0a032006-11-20 17:13:38 -08006036 sctp_transport_route(transport, (union sctp_addr *)&chunk->dest,
Eric W. Biederman2ce95502012-08-06 08:43:06 +00006037 sctp_sk(net->sctp.ctl_sock));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006038
6039 packet = sctp_packet_init(&transport->packet, transport, sport, dport);
6040 packet = sctp_packet_config(packet, vtag, 0);
6041
6042 return packet;
6043
6044nomem:
6045 return NULL;
6046}
6047
6048/* Free the packet allocated earlier for responding in the OOTB condition. */
6049void sctp_ootb_pkt_free(struct sctp_packet *packet)
6050{
6051 sctp_transport_free(packet->transport);
6052}
6053
6054/* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00006055static void sctp_send_stale_cookie_err(struct net *net,
6056 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07006057 const struct sctp_association *asoc,
6058 const struct sctp_chunk *chunk,
6059 sctp_cmd_seq_t *commands,
6060 struct sctp_chunk *err_chunk)
6061{
6062 struct sctp_packet *packet;
6063
6064 if (err_chunk) {
Eric W. Biederman2ce95502012-08-06 08:43:06 +00006065 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006066 if (packet) {
6067 struct sctp_signed_cookie *cookie;
6068
6069 /* Override the OOTB vtag from the cookie. */
6070 cookie = chunk->subh.cookie_hdr;
6071 packet->vtag = cookie->c.peer_vtag;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09006072
Linus Torvalds1da177e2005-04-16 15:20:36 -07006073 /* Set the skb to the belonging sock for accounting. */
6074 err_chunk->skb->sk = ep->base.sk;
6075 sctp_packet_append_chunk(packet, err_chunk);
6076 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
6077 SCTP_PACKET(packet));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006078 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006079 } else
6080 sctp_chunk_free (err_chunk);
6081 }
6082}
6083
6084
6085/* Process a data chunk */
6086static int sctp_eat_data(const struct sctp_association *asoc,
6087 struct sctp_chunk *chunk,
6088 sctp_cmd_seq_t *commands)
6089{
6090 sctp_datahdr_t *data_hdr;
6091 struct sctp_chunk *err;
6092 size_t datalen;
6093 sctp_verb_t deliver;
6094 int tmp;
6095 __u32 tsn;
Neil Horman7c3ceb4f2006-05-05 17:02:09 -07006096 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
Neil Horman049b3ff2005-11-11 16:08:24 -08006097 struct sock *sk = asoc->base.sk;
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00006098 struct net *net = sock_net(sk);
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006099 u16 ssn;
6100 u16 sid;
6101 u8 ordered = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07006102
6103 data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data;
6104 skb_pull(chunk->skb, sizeof(sctp_datahdr_t));
6105
6106 tsn = ntohl(data_hdr->tsn);
Daniel Borkmannbb333812013-06-28 19:49:40 +02006107 pr_debug("%s: TSN 0x%x\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006108
6109 /* ASSERT: Now skb->data is really the user data. */
6110
Linus Torvalds1da177e2005-04-16 15:20:36 -07006111 /* Process ECN based congestion.
6112 *
6113 * Since the chunk structure is reused for all chunks within
6114 * a packet, we use ecn_ce_done to track if we've already
6115 * done CE processing for this packet.
6116 *
6117 * We need to do ECN processing even if we plan to discard the
6118 * chunk later.
6119 */
6120
Marcelo Ricardo Leitner2d47fd12016-07-13 15:09:00 -03006121 if (asoc->peer.ecn_capable && !chunk->ecn_ce_done) {
Marcelo Ricardo Leitnere7487c82016-07-13 15:08:58 -03006122 struct sctp_af *af = SCTP_INPUT_CB(chunk->skb)->af;
Linus Torvalds1da177e2005-04-16 15:20:36 -07006123 chunk->ecn_ce_done = 1;
6124
Marcelo Ricardo Leitner2d47fd12016-07-13 15:09:00 -03006125 if (af->is_ce(sctp_gso_headskb(chunk->skb))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07006126 /* Do real work as sideffect. */
6127 sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE,
6128 SCTP_U32(tsn));
6129 }
6130 }
6131
6132 tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn);
6133 if (tmp < 0) {
6134 /* The TSN is too high--silently discard the chunk and
6135 * count on it getting retransmitted later.
6136 */
Michele Baldessari196d6752012-12-01 04:49:42 +00006137 if (chunk->asoc)
6138 chunk->asoc->stats.outofseqtsns++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07006139 return SCTP_IERROR_HIGH_TSN;
6140 } else if (tmp > 0) {
6141 /* This is a duplicate. Record it. */
6142 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn));
6143 return SCTP_IERROR_DUP_TSN;
6144 }
6145
6146 /* This is a new TSN. */
6147
6148 /* Discard if there is no room in the receive window.
6149 * Actually, allow a little bit of overflow (up to a MTU).
6150 */
6151 datalen = ntohs(chunk->chunk_hdr->length);
6152 datalen -= sizeof(sctp_data_chunk_t);
6153
6154 deliver = SCTP_CMD_CHUNK_ULP;
6155
6156 /* Think about partial delivery. */
6157 if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) {
6158
6159 /* Even if we don't accept this chunk there is
6160 * memory pressure.
6161 */
6162 sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL());
6163 }
6164
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09006165 /* Spill over rwnd a little bit. Note: While allowed, this spill over
Linus Torvalds1da177e2005-04-16 15:20:36 -07006166 * seems a bit troublesome in that frag_point varies based on
6167 * PMTU. In cases, such as loopback, this might be a rather
6168 * large spill over.
6169 */
Daniel Borkmann362d5202014-04-14 21:45:17 +02006170 if ((!chunk->data_accepted) && (!asoc->rwnd || asoc->rwnd_over ||
Neil Horman4d93df02007-08-15 16:07:44 -07006171 (datalen > asoc->rwnd + asoc->frag_point))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07006172
6173 /* If this is the next TSN, consider reneging to make
6174 * room. Note: Playing nice with a confused sender. A
6175 * malicious sender can still eat up all our buffer
6176 * space and in the future we may want to detect and
6177 * do more drastic reneging.
6178 */
Neil Horman7c3ceb4f2006-05-05 17:02:09 -07006179 if (sctp_tsnmap_has_gap(map) &&
6180 (sctp_tsnmap_get_ctsn(map) + 1) == tsn) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02006181 pr_debug("%s: reneging for tsn:%u\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006182 deliver = SCTP_CMD_RENEGE;
6183 } else {
Daniel Borkmannbb333812013-06-28 19:49:40 +02006184 pr_debug("%s: discard tsn:%u len:%zu, rwnd:%d\n",
6185 __func__, tsn, datalen, asoc->rwnd);
6186
Linus Torvalds1da177e2005-04-16 15:20:36 -07006187 return SCTP_IERROR_IGNORE_TSN;
6188 }
6189 }
6190
6191 /*
Neil Horman4d93df02007-08-15 16:07:44 -07006192 * Also try to renege to limit our memory usage in the event that
6193 * we are under memory pressure
Hideo Aoki3ab224b2007-12-31 00:11:19 -08006194 * If we can't renege, don't worry about it, the sk_rmem_schedule
Neil Horman4d93df02007-08-15 16:07:44 -07006195 * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our
6196 * memory usage too much
6197 */
6198 if (*sk->sk_prot_creator->memory_pressure) {
6199 if (sctp_tsnmap_has_gap(map) &&
wangweidongf7010e62013-12-23 12:16:52 +08006200 (sctp_tsnmap_get_ctsn(map) + 1) == tsn) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02006201 pr_debug("%s: under pressure, reneging for tsn:%u\n",
6202 __func__, tsn);
Neil Horman4d93df02007-08-15 16:07:44 -07006203 deliver = SCTP_CMD_RENEGE;
6204 }
6205 }
6206
6207 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07006208 * Section 3.3.10.9 No User Data (9)
6209 *
6210 * Cause of error
6211 * ---------------
6212 * No User Data: This error cause is returned to the originator of a
6213 * DATA chunk if a received DATA chunk has no user data.
6214 */
6215 if (unlikely(0 == datalen)) {
6216 err = sctp_make_abort_no_data(asoc, chunk, tsn);
6217 if (err) {
6218 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
6219 SCTP_CHUNK(err));
6220 }
6221 /* We are going to ABORT, so we might as well stop
6222 * processing the rest of the chunks in the packet.
6223 */
wangweidongcb3f8372013-12-23 12:16:50 +08006224 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07006225 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
6226 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006227 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08006228 SCTP_PERR(SCTP_ERROR_NO_DATA));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006229 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
6230 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006231 return SCTP_IERROR_NO_DATA;
6232 }
6233
Sridhar Samudrala9faa7302006-07-21 14:49:07 -07006234 chunk->data_accepted = 1;
6235
Linus Torvalds1da177e2005-04-16 15:20:36 -07006236 /* Note: Some chunks may get overcounted (if we drop) or overcounted
6237 * if we renege and the chunk arrives again.
6238 */
Michele Baldessari196d6752012-12-01 04:49:42 +00006239 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006240 SCTP_INC_STATS(net, SCTP_MIB_INUNORDERCHUNKS);
Michele Baldessari196d6752012-12-01 04:49:42 +00006241 if (chunk->asoc)
6242 chunk->asoc->stats.iuodchunks++;
6243 } else {
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006244 SCTP_INC_STATS(net, SCTP_MIB_INORDERCHUNKS);
Michele Baldessari196d6752012-12-01 04:49:42 +00006245 if (chunk->asoc)
6246 chunk->asoc->stats.iodchunks++;
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006247 ordered = 1;
6248 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07006249
6250 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
6251 *
6252 * If an endpoint receive a DATA chunk with an invalid stream
6253 * identifier, it shall acknowledge the reception of the DATA chunk
6254 * following the normal procedure, immediately send an ERROR chunk
6255 * with cause set to "Invalid Stream Identifier" (See Section 3.3.10)
6256 * and discard the DATA chunk.
6257 */
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006258 sid = ntohs(data_hdr->stream);
6259 if (sid >= asoc->c.sinit_max_instreams) {
Vlad Yasevich3888e9e2008-07-08 02:28:39 -07006260 /* Mark tsn as received even though we drop it */
6261 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn));
6262
Linus Torvalds1da177e2005-04-16 15:20:36 -07006263 err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM,
6264 &data_hdr->stream,
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05006265 sizeof(data_hdr->stream),
6266 sizeof(u16));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006267 if (err)
6268 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
6269 SCTP_CHUNK(err));
6270 return SCTP_IERROR_BAD_STREAM;
6271 }
6272
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006273 /* Check to see if the SSN is possible for this TSN.
6274 * The biggest gap we can record is 4K wide. Since SSNs wrap
6275 * at an unsigned short, there is no way that an SSN can
6276 * wrap and for a valid TSN. We can simply check if the current
6277 * SSN is smaller then the next expected one. If it is, it wrapped
6278 * and is invalid.
6279 */
6280 ssn = ntohs(data_hdr->ssn);
6281 if (ordered && SSN_lt(ssn, sctp_ssn_peek(&asoc->ssnmap->in, sid))) {
6282 return SCTP_IERROR_PROTO_VIOLATION;
6283 }
6284
Linus Torvalds1da177e2005-04-16 15:20:36 -07006285 /* Send the data up to the user. Note: Schedule the
6286 * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK
6287 * chunk needs the updated rwnd.
6288 */
6289 sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk));
6290
6291 return SCTP_IERROR_NO_ERROR;
6292}