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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.
856 * We are the side that is being asked for an association.
857 *
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;
2309 time_t stale;
2310 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:
2979 goto consume;
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;
3046consume:
3047 return SCTP_DISPOSITION_CONSUME;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003048
Linus Torvalds1da177e2005-04-16 15:20:36 -07003049}
3050
3051/*
3052 * sctp_sf_eat_data_fast_4_4
3053 *
3054 * Section: 4 (4)
3055 * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received
3056 * DATA chunks without delay.
3057 *
3058 * Verification Tag: 8.5 Verification Tag [Normal verification]
3059 * Inputs
3060 * (endpoint, asoc, chunk)
3061 *
3062 * Outputs
3063 * (asoc, reply_msg, msg_up, timers, counters)
3064 *
3065 * The return value is the disposition of the chunk.
3066 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003067sctp_disposition_t sctp_sf_eat_data_fast_4_4(struct net *net,
3068 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003069 const struct sctp_association *asoc,
3070 const sctp_subtype_t type,
3071 void *arg,
3072 sctp_cmd_seq_t *commands)
3073{
3074 struct sctp_chunk *chunk = arg;
3075 int error;
3076
3077 if (!sctp_vtag_verify(chunk, asoc)) {
3078 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3079 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003080 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003081 }
3082
3083 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003084 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003085 commands);
3086
wangweidongcb3f8372013-12-23 12:16:50 +08003087 error = sctp_eat_data(asoc, chunk, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003088 switch (error) {
3089 case SCTP_IERROR_NO_ERROR:
3090 case SCTP_IERROR_HIGH_TSN:
3091 case SCTP_IERROR_DUP_TSN:
3092 case SCTP_IERROR_IGNORE_TSN:
3093 case SCTP_IERROR_BAD_STREAM:
3094 break;
3095 case SCTP_IERROR_NO_DATA:
3096 goto consume;
Vlad Yasevichf1751c52009-09-04 18:21:03 -04003097 case SCTP_IERROR_PROTO_VIOLATION:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003098 return sctp_sf_abort_violation(net, ep, asoc, chunk, commands,
Vlad Yasevichf1751c52009-09-04 18:21:03 -04003099 (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003100 default:
3101 BUG();
3102 }
3103
3104 /* Go a head and force a SACK, since we are shutting down. */
3105
3106 /* Implementor's Guide.
3107 *
3108 * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately
3109 * respond to each received packet containing one or more DATA chunk(s)
3110 * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer
3111 */
3112 if (chunk->end_of_packet) {
3113 /* We must delay the chunk creation since the cumulative
3114 * TSN has not been updated yet.
3115 */
3116 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL());
3117 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
3118 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
3119 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
3120 }
3121
3122consume:
3123 return SCTP_DISPOSITION_CONSUME;
3124}
3125
3126/*
3127 * Section: 6.2 Processing a Received SACK
3128 * D) Any time a SACK arrives, the endpoint performs the following:
3129 *
3130 * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point,
3131 * then drop the SACK. Since Cumulative TSN Ack is monotonically
3132 * increasing, a SACK whose Cumulative TSN Ack is less than the
3133 * Cumulative TSN Ack Point indicates an out-of-order SACK.
3134 *
3135 * ii) Set rwnd equal to the newly received a_rwnd minus the number
3136 * of bytes still outstanding after processing the Cumulative TSN Ack
3137 * and the Gap Ack Blocks.
3138 *
3139 * iii) If the SACK is missing a TSN that was previously
3140 * acknowledged via a Gap Ack Block (e.g., the data receiver
3141 * reneged on the data), then mark the corresponding DATA chunk
3142 * as available for retransmit: Mark it as missing for fast
3143 * retransmit as described in Section 7.2.4 and if no retransmit
3144 * timer is running for the destination address to which the DATA
3145 * chunk was originally transmitted, then T3-rtx is started for
3146 * that destination address.
3147 *
3148 * Verification Tag: 8.5 Verification Tag [Normal verification]
3149 *
3150 * Inputs
3151 * (endpoint, asoc, chunk)
3152 *
3153 * Outputs
3154 * (asoc, reply_msg, msg_up, timers, counters)
3155 *
3156 * The return value is the disposition of the chunk.
3157 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003158sctp_disposition_t sctp_sf_eat_sack_6_2(struct net *net,
3159 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003160 const struct sctp_association *asoc,
3161 const sctp_subtype_t type,
3162 void *arg,
3163 sctp_cmd_seq_t *commands)
3164{
3165 struct sctp_chunk *chunk = arg;
3166 sctp_sackhdr_t *sackh;
3167 __u32 ctsn;
3168
3169 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003170 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003171
3172 /* Make sure that the SACK chunk has a valid length. */
3173 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_sack_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003174 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003175 commands);
3176
3177 /* Pull the SACK chunk from the data buffer */
3178 sackh = sctp_sm_pull_sack(chunk);
3179 /* Was this a bogus SACK? */
3180 if (!sackh)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003181 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003182 chunk->subh.sack_hdr = sackh;
3183 ctsn = ntohl(sackh->cum_tsn_ack);
3184
3185 /* i) If Cumulative TSN Ack is less than the Cumulative TSN
3186 * Ack Point, then drop the SACK. Since Cumulative TSN
3187 * Ack is monotonically increasing, a SACK whose
3188 * Cumulative TSN Ack is less than the Cumulative TSN Ack
3189 * Point indicates an out-of-order SACK.
3190 */
3191 if (TSN_lt(ctsn, asoc->ctsn_ack_point)) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02003192 pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn,
3193 asoc->ctsn_ack_point);
3194
Linus Torvalds1da177e2005-04-16 15:20:36 -07003195 return SCTP_DISPOSITION_DISCARD;
3196 }
3197
Wei Yongjunaecedea2007-08-02 16:57:44 +08003198 /* If Cumulative TSN Ack beyond the max tsn currently
3199 * send, terminating the association and respond to the
3200 * sender with an ABORT.
3201 */
3202 if (!TSN_lt(ctsn, asoc->next_tsn))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003203 return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands);
Wei Yongjunaecedea2007-08-02 16:57:44 +08003204
Linus Torvalds1da177e2005-04-16 15:20:36 -07003205 /* Return this SACK for further processing. */
Nicolas Dichteledfee032012-10-03 05:43:22 +00003206 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_CHUNK(chunk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003207
3208 /* Note: We do the rest of the work on the PROCESS_SACK
3209 * sideeffect.
3210 */
3211 return SCTP_DISPOSITION_CONSUME;
3212}
3213
3214/*
3215 * Generate an ABORT in response to a packet.
3216 *
Jerome Forissier047a2422005-04-28 11:58:43 -07003217 * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41
Linus Torvalds1da177e2005-04-16 15:20:36 -07003218 *
Jerome Forissier047a2422005-04-28 11:58:43 -07003219 * 8) The receiver should respond to the sender of the OOTB packet with
3220 * an ABORT. When sending the ABORT, the receiver of the OOTB packet
3221 * MUST fill in the Verification Tag field of the outbound packet
3222 * with the value found in the Verification Tag field of the OOTB
3223 * packet and set the T-bit in the Chunk Flags to indicate that the
3224 * Verification Tag is reflected. After sending this ABORT, the
3225 * receiver of the OOTB packet shall discard the OOTB packet and take
3226 * no further action.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003227 *
3228 * Verification Tag:
3229 *
3230 * The return value is the disposition of the chunk.
3231*/
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003232static sctp_disposition_t sctp_sf_tabort_8_4_8(struct net *net,
3233 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003234 const struct sctp_association *asoc,
3235 const sctp_subtype_t type,
3236 void *arg,
3237 sctp_cmd_seq_t *commands)
3238{
3239 struct sctp_packet *packet = NULL;
3240 struct sctp_chunk *chunk = arg;
3241 struct sctp_chunk *abort;
3242
Eric W. Biederman2ce95502012-08-06 08:43:06 +00003243 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003244
3245 if (packet) {
3246 /* Make an ABORT. The T bit will be set if the asoc
3247 * is NULL.
3248 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003249 abort = sctp_make_abort(asoc, chunk, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003250 if (!abort) {
3251 sctp_ootb_pkt_free(packet);
3252 return SCTP_DISPOSITION_NOMEM;
3253 }
3254
Jerome Forissier047a2422005-04-28 11:58:43 -07003255 /* Reflect vtag if T-Bit is set */
3256 if (sctp_test_T_bit(abort))
3257 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
3258
Linus Torvalds1da177e2005-04-16 15:20:36 -07003259 /* Set the skb to the belonging sock for accounting. */
3260 abort->skb->sk = ep->base.sk;
3261
3262 sctp_packet_append_chunk(packet, abort);
3263
3264 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
3265 SCTP_PACKET(packet));
3266
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003267 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003268
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003269 sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003270 return SCTP_DISPOSITION_CONSUME;
3271 }
3272
3273 return SCTP_DISPOSITION_NOMEM;
3274}
3275
3276/*
3277 * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR
3278 * event as ULP notification for each cause included in the chunk.
3279 *
3280 * API 5.3.1.3 - SCTP_REMOTE_ERROR
3281 *
3282 * The return value is the disposition of the chunk.
3283*/
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003284sctp_disposition_t sctp_sf_operr_notify(struct net *net,
3285 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003286 const struct sctp_association *asoc,
3287 const sctp_subtype_t type,
3288 void *arg,
3289 sctp_cmd_seq_t *commands)
3290{
3291 struct sctp_chunk *chunk = arg;
Shan Wei8a00be12011-04-19 21:25:40 +00003292 sctp_errhdr_t *err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003293
3294 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003295 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003296
3297 /* Make sure that the ERROR chunk has a valid length. */
3298 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003299 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003300 commands);
Shan Wei8a00be12011-04-19 21:25:40 +00003301 sctp_walk_errors(err, chunk->chunk_hdr);
3302 if ((void *)err != (void *)chunk->chunk_end)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003303 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
Shan Wei8a00be12011-04-19 21:25:40 +00003304 (void *)err, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003305
Wei Yongjun3df26782009-03-02 06:46:51 +00003306 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR,
3307 SCTP_CHUNK(chunk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003308
Linus Torvalds1da177e2005-04-16 15:20:36 -07003309 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003310}
3311
3312/*
3313 * Process an inbound SHUTDOWN ACK.
3314 *
3315 * From Section 9.2:
3316 * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall
3317 * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its
3318 * peer, and remove all record of the association.
3319 *
3320 * The return value is the disposition.
3321 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003322sctp_disposition_t sctp_sf_do_9_2_final(struct net *net,
3323 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003324 const struct sctp_association *asoc,
3325 const sctp_subtype_t type,
3326 void *arg,
3327 sctp_cmd_seq_t *commands)
3328{
3329 struct sctp_chunk *chunk = arg;
3330 struct sctp_chunk *reply;
3331 struct sctp_ulpevent *ev;
3332
3333 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003334 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003335
3336 /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */
3337 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003338 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003339 commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003340 /* 10.2 H) SHUTDOWN COMPLETE notification
3341 *
3342 * When SCTP completes the shutdown procedures (section 9.2) this
3343 * notification is passed to the upper layer.
3344 */
3345 ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP,
Vlad Yasevicha5a35e72007-03-23 11:34:08 -07003346 0, 0, 0, NULL, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003347 if (!ev)
3348 goto nomem;
3349
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07003350 /* ...send a SHUTDOWN COMPLETE chunk to its peer, */
3351 reply = sctp_make_shutdown_complete(asoc, chunk);
3352 if (!reply)
3353 goto nomem_chunk;
3354
3355 /* Do all the commands now (after allocation), so that we
3356 * have consistent state if memory allocation failes
3357 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003358 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
3359
3360 /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall
3361 * stop the T2-shutdown timer,
3362 */
3363 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3364 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
3365
3366 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3367 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
3368
Linus Torvalds1da177e2005-04-16 15:20:36 -07003369 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
3370 SCTP_STATE(SCTP_STATE_CLOSED));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003371 SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS);
3372 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003373 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
3374
3375 /* ...and remove all record of the association. */
3376 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
3377 return SCTP_DISPOSITION_DELETE_TCB;
3378
Vladislav Yasevichdf7deeb2006-08-22 00:19:51 -07003379nomem_chunk:
3380 sctp_ulpevent_free(ev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003381nomem:
3382 return SCTP_DISPOSITION_NOMEM;
3383}
3384
3385/*
Jerome Forissier047a2422005-04-28 11:58:43 -07003386 * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41.
3387 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07003388 * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should
3389 * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE.
3390 * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB
3391 * packet must fill in the Verification Tag field of the outbound
3392 * packet with the Verification Tag received in the SHUTDOWN ACK and
Jerome Forissier047a2422005-04-28 11:58:43 -07003393 * set the T-bit in the Chunk Flags to indicate that the Verification
3394 * Tag is reflected.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003395 *
3396 * 8) The receiver should respond to the sender of the OOTB packet with
3397 * an ABORT. When sending the ABORT, the receiver of the OOTB packet
3398 * MUST fill in the Verification Tag field of the outbound packet
3399 * with the value found in the Verification Tag field of the OOTB
Jerome Forissier047a2422005-04-28 11:58:43 -07003400 * packet and set the T-bit in the Chunk Flags to indicate that the
3401 * Verification Tag is reflected. After sending this ABORT, the
3402 * receiver of the OOTB packet shall discard the OOTB packet and take
3403 * no further action.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003404 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003405sctp_disposition_t sctp_sf_ootb(struct net *net,
3406 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003407 const struct sctp_association *asoc,
3408 const sctp_subtype_t type,
3409 void *arg,
3410 sctp_cmd_seq_t *commands)
3411{
3412 struct sctp_chunk *chunk = arg;
3413 struct sk_buff *skb = chunk->skb;
3414 sctp_chunkhdr_t *ch;
Shan Wei85c5ed42011-04-19 21:30:01 +00003415 sctp_errhdr_t *err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003416 __u8 *ch_end;
3417 int ootb_shut_ack = 0;
Shan Wei85c5ed42011-04-19 21:30:01 +00003418 int ootb_cookie_ack = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003419
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003420 SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003421
3422 ch = (sctp_chunkhdr_t *) chunk->chunk_hdr;
3423 do {
Vlad Yasevichece25df2007-09-07 16:30:54 -04003424 /* Report violation if the chunk is less then minimal */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003425 if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003426 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04003427 commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003428
Vlad Yasevichece25df2007-09-07 16:30:54 -04003429 /* Now that we know we at least have a chunk header,
3430 * do things that are type appropriate.
3431 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003432 if (SCTP_CID_SHUTDOWN_ACK == ch->type)
3433 ootb_shut_ack = 1;
3434
3435 /* RFC 2960, Section 3.3.7
3436 * Moreover, under any circumstances, an endpoint that
3437 * receives an ABORT MUST NOT respond to that ABORT by
3438 * sending an ABORT of its own.
3439 */
3440 if (SCTP_CID_ABORT == ch->type)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003441 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003442
Shan Wei85c5ed42011-04-19 21:30:01 +00003443 /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR
3444 * or a COOKIE ACK the SCTP Packet should be silently
3445 * discarded.
3446 */
3447
3448 if (SCTP_CID_COOKIE_ACK == ch->type)
3449 ootb_cookie_ack = 1;
3450
3451 if (SCTP_CID_ERROR == ch->type) {
3452 sctp_walk_errors(err, ch) {
3453 if (SCTP_ERROR_STALE_COOKIE == err->cause) {
3454 ootb_cookie_ack = 1;
3455 break;
3456 }
3457 }
3458 }
3459
Vlad Yasevichece25df2007-09-07 16:30:54 -04003460 /* Report violation if chunk len overflows */
3461 ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
3462 if (ch_end > skb_tail_pointer(skb))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003463 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04003464 commands);
3465
Linus Torvalds1da177e2005-04-16 15:20:36 -07003466 ch = (sctp_chunkhdr_t *) ch_end;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07003467 } while (ch_end < skb_tail_pointer(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003468
3469 if (ootb_shut_ack)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003470 return sctp_sf_shut_8_4_5(net, ep, asoc, type, arg, commands);
Shan Wei85c5ed42011-04-19 21:30:01 +00003471 else if (ootb_cookie_ack)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003472 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003473 else
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003474 return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003475}
3476
3477/*
3478 * Handle an "Out of the blue" SHUTDOWN ACK.
3479 *
Jerome Forissier047a2422005-04-28 11:58:43 -07003480 * Section: 8.4 5, sctpimpguide 2.41.
3481 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07003482 * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should
Jerome Forissier047a2422005-04-28 11:58:43 -07003483 * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE.
3484 * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB
3485 * packet must fill in the Verification Tag field of the outbound
3486 * packet with the Verification Tag received in the SHUTDOWN ACK and
3487 * set the T-bit in the Chunk Flags to indicate that the Verification
3488 * Tag is reflected.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003489 *
3490 * Inputs
3491 * (endpoint, asoc, type, arg, commands)
3492 *
3493 * Outputs
3494 * (sctp_disposition_t)
3495 *
3496 * The return value is the disposition of the chunk.
3497 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003498static sctp_disposition_t sctp_sf_shut_8_4_5(struct net *net,
3499 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003500 const struct sctp_association *asoc,
3501 const sctp_subtype_t type,
3502 void *arg,
3503 sctp_cmd_seq_t *commands)
3504{
3505 struct sctp_packet *packet = NULL;
3506 struct sctp_chunk *chunk = arg;
3507 struct sctp_chunk *shut;
3508
Eric W. Biederman2ce95502012-08-06 08:43:06 +00003509 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003510
3511 if (packet) {
3512 /* Make an SHUTDOWN_COMPLETE.
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003513 * The T bit will be set if the asoc is NULL.
3514 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003515 shut = sctp_make_shutdown_complete(asoc, chunk);
3516 if (!shut) {
3517 sctp_ootb_pkt_free(packet);
3518 return SCTP_DISPOSITION_NOMEM;
3519 }
3520
Jerome Forissier047a2422005-04-28 11:58:43 -07003521 /* Reflect vtag if T-Bit is set */
3522 if (sctp_test_T_bit(shut))
3523 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
3524
Linus Torvalds1da177e2005-04-16 15:20:36 -07003525 /* Set the skb to the belonging sock for accounting. */
3526 shut->skb->sk = ep->base.sk;
3527
3528 sctp_packet_append_chunk(packet, shut);
3529
3530 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
3531 SCTP_PACKET(packet));
3532
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003533 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003534
3535 /* If the chunk length is invalid, we don't want to process
3536 * the reset of the packet.
3537 */
3538 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003539 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003540
Vlad Yasevichd3f25962007-09-07 11:47:45 -04003541 /* We need to discard the rest of the packet to prevent
3542 * potential bomming attacks from additional bundled chunks.
3543 * This is documented in SCTP Threats ID.
3544 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003545 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003546 }
3547
3548 return SCTP_DISPOSITION_NOMEM;
3549}
3550
3551/*
3552 * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state.
3553 *
3554 * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK
3555 * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the
3556 * procedures in section 8.4 SHOULD be followed, in other words it
3557 * should be treated as an Out Of The Blue packet.
3558 * [This means that we do NOT check the Verification Tag on these
3559 * chunks. --piggy ]
3560 *
3561 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003562sctp_disposition_t sctp_sf_do_8_5_1_E_sa(struct net *net,
3563 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003564 const struct sctp_association *asoc,
3565 const sctp_subtype_t type,
3566 void *arg,
3567 sctp_cmd_seq_t *commands)
3568{
Vlad Yasevichece25df2007-09-07 16:30:54 -04003569 struct sctp_chunk *chunk = arg;
3570
3571 /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */
3572 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003573 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04003574 commands);
3575
Linus Torvalds1da177e2005-04-16 15:20:36 -07003576 /* Although we do have an association in this case, it corresponds
3577 * to a restarted association. So the packet is treated as an OOTB
3578 * packet and the state function that handles OOTB SHUTDOWN_ACK is
3579 * called with a NULL association.
3580 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003581 SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
Wei Yongjun8190f892008-09-08 12:13:55 +08003582
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003583 return sctp_sf_shut_8_4_5(net, ep, NULL, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003584}
3585
3586/* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003587sctp_disposition_t sctp_sf_do_asconf(struct net *net,
3588 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003589 const struct sctp_association *asoc,
3590 const sctp_subtype_t type, void *arg,
3591 sctp_cmd_seq_t *commands)
3592{
3593 struct sctp_chunk *chunk = arg;
3594 struct sctp_chunk *asconf_ack = NULL;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003595 struct sctp_paramhdr *err_param = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003596 sctp_addiphdr_t *hdr;
3597 __u32 serial;
3598
3599 if (!sctp_vtag_verify(chunk, asoc)) {
3600 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3601 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003602 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003603 }
3604
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003605 /* ADD-IP: Section 4.1.1
3606 * This chunk MUST be sent in an authenticated way by using
3607 * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk
3608 * is received unauthenticated it MUST be silently discarded as
3609 * described in [I-D.ietf-tsvwg-sctp-auth].
3610 */
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00003611 if (!net->sctp.addip_noauth && !chunk->auth)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003612 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003613
Linus Torvalds1da177e2005-04-16 15:20:36 -07003614 /* Make sure that the ASCONF ADDIP chunk has a valid length. */
3615 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003616 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003617 commands);
3618
3619 hdr = (sctp_addiphdr_t *)chunk->skb->data;
3620 serial = ntohl(hdr->serial);
3621
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003622 /* Verify the ASCONF chunk before processing it. */
Daniel Borkmann9de79222014-10-09 22:55:31 +02003623 if (!sctp_verify_asconf(asoc, chunk, true, &err_param))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003624 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
Wei Yongjunba016672008-09-30 05:32:24 -07003625 (void *)err_param, commands);
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003626
Vlad Yasevicha08de642007-12-20 14:11:47 -08003627 /* ADDIP 5.2 E1) Compare the value of the serial number to the value
Linus Torvalds1da177e2005-04-16 15:20:36 -07003628 * the endpoint stored in a new association variable
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003629 * 'Peer-Serial-Number'.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003630 */
3631 if (serial == asoc->peer.addip_serial + 1) {
Vlad Yasevicha08de642007-12-20 14:11:47 -08003632 /* If this is the first instance of ASCONF in the packet,
3633 * we can clean our old ASCONF-ACKs.
3634 */
3635 if (!chunk->has_asconf)
3636 sctp_assoc_clean_asconf_ack_cache(asoc);
3637
3638 /* ADDIP 5.2 E4) When the Sequence Number matches the next one
3639 * expected, process the ASCONF as described below and after
3640 * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to
3641 * the response packet and cache a copy of it (in the event it
3642 * later needs to be retransmitted).
3643 *
3644 * Essentially, do V1-V5.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003645 */
3646 asconf_ack = sctp_process_asconf((struct sctp_association *)
3647 asoc, chunk);
3648 if (!asconf_ack)
3649 return SCTP_DISPOSITION_NOMEM;
Vlad Yasevicha08de642007-12-20 14:11:47 -08003650 } else if (serial < asoc->peer.addip_serial + 1) {
3651 /* ADDIP 5.2 E2)
3652 * If the value found in the Sequence Number is less than the
3653 * ('Peer- Sequence-Number' + 1), simply skip to the next
3654 * ASCONF, and include in the outbound response packet
3655 * any previously cached ASCONF-ACK response that was
3656 * sent and saved that matches the Sequence Number of the
3657 * ASCONF. Note: It is possible that no cached ASCONF-ACK
3658 * Chunk exists. This will occur when an older ASCONF
3659 * arrives out of order. In such a case, the receiver
3660 * should skip the ASCONF Chunk and not include ASCONF-ACK
3661 * Chunk for that chunk.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003662 */
Vlad Yasevicha08de642007-12-20 14:11:47 -08003663 asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial);
3664 if (!asconf_ack)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003665 return SCTP_DISPOSITION_DISCARD;
Vlad Yasevich31b02e12009-09-04 18:21:00 -04003666
3667 /* Reset the transport so that we select the correct one
3668 * this time around. This is to make sure that we don't
3669 * accidentally use a stale transport that's been removed.
3670 */
3671 asconf_ack->transport = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003672 } else {
Vlad Yasevicha08de642007-12-20 14:11:47 -08003673 /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since
Linus Torvalds1da177e2005-04-16 15:20:36 -07003674 * it must be either a stale packet or from an attacker.
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003675 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003676 return SCTP_DISPOSITION_DISCARD;
3677 }
3678
Vlad Yasevicha08de642007-12-20 14:11:47 -08003679 /* ADDIP 5.2 E6) The destination address of the SCTP packet
3680 * containing the ASCONF-ACK Chunks MUST be the source address of
3681 * the SCTP packet that held the ASCONF Chunks.
3682 *
3683 * To do this properly, we'll set the destination address of the chunk
3684 * and at the transmit time, will try look up the transport to use.
3685 * Since ASCONFs may be bundled, the correct transport may not be
Thadeu Lima de Souza Cascardo94e2bd62009-10-16 15:20:49 +02003686 * created until we process the entire packet, thus this workaround.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003687 */
Vlad Yasevicha08de642007-12-20 14:11:47 -08003688 asconf_ack->dest = chunk->source;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003689 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack));
Michio Honda6af29cc2011-06-16 17:14:34 +09003690 if (asoc->new_transport) {
wangweidongf7010e62013-12-23 12:16:52 +08003691 sctp_sf_heartbeat(ep, asoc, type, asoc->new_transport, commands);
Michio Honda6af29cc2011-06-16 17:14:34 +09003692 ((struct sctp_association *)asoc)->new_transport = NULL;
3693 }
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003694
Linus Torvalds1da177e2005-04-16 15:20:36 -07003695 return SCTP_DISPOSITION_CONSUME;
3696}
3697
3698/*
3699 * ADDIP Section 4.3 General rules for address manipulation
3700 * When building TLV parameters for the ASCONF Chunk that will add or
3701 * delete IP addresses the D0 to D13 rules should be applied:
3702 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003703sctp_disposition_t sctp_sf_do_asconf_ack(struct net *net,
3704 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003705 const struct sctp_association *asoc,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003706 const sctp_subtype_t type, void *arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003707 sctp_cmd_seq_t *commands)
3708{
3709 struct sctp_chunk *asconf_ack = arg;
3710 struct sctp_chunk *last_asconf = asoc->addip_last_asconf;
3711 struct sctp_chunk *abort;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003712 struct sctp_paramhdr *err_param = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003713 sctp_addiphdr_t *addip_hdr;
3714 __u32 sent_serial, rcvd_serial;
3715
3716 if (!sctp_vtag_verify(asconf_ack, asoc)) {
3717 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3718 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003719 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003720 }
3721
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003722 /* ADD-IP, Section 4.1.2:
3723 * This chunk MUST be sent in an authenticated way by using
3724 * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk
3725 * is received unauthenticated it MUST be silently discarded as
3726 * described in [I-D.ietf-tsvwg-sctp-auth].
3727 */
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00003728 if (!net->sctp.addip_noauth && !asconf_ack->auth)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003729 return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands);
Vlad Yasevich6afd2e82007-12-20 14:08:04 -08003730
Linus Torvalds1da177e2005-04-16 15:20:36 -07003731 /* Make sure that the ADDIP chunk has a valid length. */
3732 if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003733 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003734 commands);
3735
3736 addip_hdr = (sctp_addiphdr_t *)asconf_ack->skb->data;
3737 rcvd_serial = ntohl(addip_hdr->serial);
3738
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003739 /* Verify the ASCONF-ACK chunk before processing it. */
Daniel Borkmann9de79222014-10-09 22:55:31 +02003740 if (!sctp_verify_asconf(asoc, asconf_ack, false, &err_param))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003741 return sctp_sf_violation_paramlen(net, ep, asoc, type, arg,
Wei Yongjunba016672008-09-30 05:32:24 -07003742 (void *)err_param, commands);
Wei Yongjun6f4c6182007-09-19 17:19:52 +08003743
Linus Torvalds1da177e2005-04-16 15:20:36 -07003744 if (last_asconf) {
3745 addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr;
3746 sent_serial = ntohl(addip_hdr->serial);
3747 } else {
3748 sent_serial = asoc->addip_serial - 1;
3749 }
3750
3751 /* D0) If an endpoint receives an ASCONF-ACK that is greater than or
3752 * equal to the next serial number to be used but no ASCONF chunk is
3753 * outstanding the endpoint MUST ABORT the association. Note that a
3754 * sequence number is greater than if it is no more than 2^^31-1
3755 * larger than the current sequence number (using serial arithmetic).
3756 */
3757 if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) &&
3758 !(asoc->addip_last_asconf)) {
3759 abort = sctp_make_abort(asoc, asconf_ack,
3760 sizeof(sctp_errhdr_t));
3761 if (abort) {
Wei Yongjun00f1c2d2007-08-21 15:50:01 +08003762 sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003763 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
3764 SCTP_CHUNK(abort));
3765 }
3766 /* We are going to ABORT, so we might as well stop
3767 * processing the rest of the chunks in the packet.
3768 */
3769 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3770 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
wangweidongcb3f8372013-12-23 12:16:50 +08003771 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07003772 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003773 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003774 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08003775 SCTP_PERR(SCTP_ERROR_ASCONF_ACK));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003776 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
3777 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003778 return SCTP_DISPOSITION_ABORT;
3779 }
3780
3781 if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) {
3782 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
3783 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
3784
3785 if (!sctp_process_asconf_ack((struct sctp_association *)asoc,
Vlad Yasevichc0786692010-04-28 08:47:22 +00003786 asconf_ack)) {
3787 /* Successfully processed ASCONF_ACK. We can
3788 * release the next asconf if we have one.
3789 */
3790 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_NEXT_ASCONF,
3791 SCTP_NULL());
Linus Torvalds1da177e2005-04-16 15:20:36 -07003792 return SCTP_DISPOSITION_CONSUME;
Vlad Yasevichc0786692010-04-28 08:47:22 +00003793 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003794
3795 abort = sctp_make_abort(asoc, asconf_ack,
3796 sizeof(sctp_errhdr_t));
3797 if (abort) {
Wei Yongjun00f1c2d2007-08-21 15:50:01 +08003798 sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003799 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
3800 SCTP_CHUNK(abort));
3801 }
3802 /* We are going to ABORT, so we might as well stop
3803 * processing the rest of the chunks in the packet.
3804 */
wangweidongcb3f8372013-12-23 12:16:50 +08003805 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07003806 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003807 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003808 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08003809 SCTP_PERR(SCTP_ERROR_ASCONF_ACK));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00003810 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
3811 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003812 return SCTP_DISPOSITION_ABORT;
3813 }
3814
3815 return SCTP_DISPOSITION_DISCARD;
3816}
3817
3818/*
3819 * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP
3820 *
3821 * When a FORWARD TSN chunk arrives, the data receiver MUST first update
3822 * its cumulative TSN point to the value carried in the FORWARD TSN
3823 * chunk, and then MUST further advance its cumulative TSN point locally
3824 * if possible.
3825 * After the above processing, the data receiver MUST stop reporting any
3826 * missing TSNs earlier than or equal to the new cumulative TSN point.
3827 *
3828 * Verification Tag: 8.5 Verification Tag [Normal verification]
3829 *
3830 * The return value is the disposition of the chunk.
3831 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003832sctp_disposition_t sctp_sf_eat_fwd_tsn(struct net *net,
3833 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003834 const struct sctp_association *asoc,
3835 const sctp_subtype_t type,
3836 void *arg,
3837 sctp_cmd_seq_t *commands)
3838{
3839 struct sctp_chunk *chunk = arg;
3840 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003841 struct sctp_fwdtsn_skip *skip;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003842 __u16 len;
3843 __u32 tsn;
3844
3845 if (!sctp_vtag_verify(chunk, asoc)) {
3846 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3847 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003848 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003849 }
3850
3851 /* Make sure that the FORWARD_TSN chunk has valid length. */
3852 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003853 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003854 commands);
3855
3856 fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data;
3857 chunk->subh.fwdtsn_hdr = fwdtsn_hdr;
3858 len = ntohs(chunk->chunk_hdr->length);
3859 len -= sizeof(struct sctp_chunkhdr);
3860 skb_pull(chunk->skb, len);
3861
3862 tsn = ntohl(fwdtsn_hdr->new_cum_tsn);
Daniel Borkmannbb333812013-06-28 19:49:40 +02003863 pr_debug("%s: TSN 0x%x\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003864
3865 /* The TSN is too high--silently discard the chunk and count on it
3866 * getting retransmitted later.
3867 */
3868 if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0)
3869 goto discard_noforce;
3870
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003871 /* Silently discard the chunk if stream-id is not valid */
3872 sctp_walk_fwdtsn(skip, chunk) {
3873 if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams)
3874 goto discard_noforce;
3875 }
3876
Linus Torvalds1da177e2005-04-16 15:20:36 -07003877 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn));
3878 if (len > sizeof(struct sctp_fwdtsn_hdr))
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003879 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003880 SCTP_CHUNK(chunk));
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003881
Linus Torvalds1da177e2005-04-16 15:20:36 -07003882 /* Count this as receiving DATA. */
Neil Horman9f70f462013-12-10 06:48:15 -05003883 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003884 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
3885 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
3886 }
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003887
Linus Torvalds1da177e2005-04-16 15:20:36 -07003888 /* FIXME: For now send a SACK, but DATA processing may
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003889 * send another.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003890 */
3891 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE());
Linus Torvalds1da177e2005-04-16 15:20:36 -07003892
3893 return SCTP_DISPOSITION_CONSUME;
3894
3895discard_noforce:
3896 return SCTP_DISPOSITION_DISCARD;
3897}
3898
3899sctp_disposition_t sctp_sf_eat_fwd_tsn_fast(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003900 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003901 const struct sctp_endpoint *ep,
3902 const struct sctp_association *asoc,
3903 const sctp_subtype_t type,
3904 void *arg,
3905 sctp_cmd_seq_t *commands)
3906{
3907 struct sctp_chunk *chunk = arg;
3908 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003909 struct sctp_fwdtsn_skip *skip;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003910 __u16 len;
3911 __u32 tsn;
3912
3913 if (!sctp_vtag_verify(chunk, asoc)) {
3914 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
3915 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003916 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003917 }
3918
3919 /* Make sure that the FORWARD_TSN chunk has a valid length. */
3920 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003921 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003922 commands);
3923
3924 fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data;
3925 chunk->subh.fwdtsn_hdr = fwdtsn_hdr;
3926 len = ntohs(chunk->chunk_hdr->length);
3927 len -= sizeof(struct sctp_chunkhdr);
3928 skb_pull(chunk->skb, len);
3929
3930 tsn = ntohl(fwdtsn_hdr->new_cum_tsn);
Daniel Borkmannbb333812013-06-28 19:49:40 +02003931 pr_debug("%s: TSN 0x%x\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003932
3933 /* The TSN is too high--silently discard the chunk and count on it
3934 * getting retransmitted later.
3935 */
3936 if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0)
3937 goto gen_shutdown;
3938
Wei Yongjun9fcb95a2008-12-25 16:58:11 -08003939 /* Silently discard the chunk if stream-id is not valid */
3940 sctp_walk_fwdtsn(skip, chunk) {
3941 if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams)
3942 goto gen_shutdown;
3943 }
3944
Linus Torvalds1da177e2005-04-16 15:20:36 -07003945 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn));
3946 if (len > sizeof(struct sctp_fwdtsn_hdr))
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003947 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003948 SCTP_CHUNK(chunk));
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003949
Linus Torvalds1da177e2005-04-16 15:20:36 -07003950 /* Go a head and force a SACK, since we are shutting down. */
3951gen_shutdown:
3952 /* Implementor's Guide.
3953 *
3954 * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately
3955 * respond to each received packet containing one or more DATA chunk(s)
3956 * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer
3957 */
3958 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL());
3959 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
3960 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
3961 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
3962
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09003963 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003964}
3965
3966/*
Lucas De Marchi25985ed2011-03-30 22:57:33 -03003967 * SCTP-AUTH Section 6.3 Receiving authenticated chukns
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07003968 *
3969 * The receiver MUST use the HMAC algorithm indicated in the HMAC
3970 * Identifier field. If this algorithm was not specified by the
3971 * receiver in the HMAC-ALGO parameter in the INIT or INIT-ACK chunk
3972 * during association setup, the AUTH chunk and all chunks after it MUST
3973 * be discarded and an ERROR chunk SHOULD be sent with the error cause
3974 * defined in Section 4.1.
3975 *
3976 * If an endpoint with no shared key receives a Shared Key Identifier
3977 * other than 0, it MUST silently discard all authenticated chunks. If
3978 * the endpoint has at least one endpoint pair shared key for the peer,
3979 * it MUST use the key specified by the Shared Key Identifier if a
3980 * key has been configured for that Shared Key Identifier. If no
3981 * endpoint pair shared key has been configured for that Shared Key
3982 * Identifier, all authenticated chunks MUST be silently discarded.
3983 *
3984 * Verification Tag: 8.5 Verification Tag [Normal verification]
3985 *
3986 * The return value is the disposition of the chunk.
3987 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00003988static sctp_ierror_t sctp_sf_authenticate(struct net *net,
3989 const struct sctp_endpoint *ep,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07003990 const struct sctp_association *asoc,
3991 const sctp_subtype_t type,
3992 struct sctp_chunk *chunk)
3993{
3994 struct sctp_authhdr *auth_hdr;
3995 struct sctp_hmac *hmac;
3996 unsigned int sig_len;
3997 __u16 key_id;
3998 __u8 *save_digest;
3999 __u8 *digest;
4000
4001 /* Pull in the auth header, so we can do some more verification */
4002 auth_hdr = (struct sctp_authhdr *)chunk->skb->data;
4003 chunk->subh.auth_hdr = auth_hdr;
4004 skb_pull(chunk->skb, sizeof(struct sctp_authhdr));
4005
Masanari Iida02582e92012-08-22 19:11:26 +09004006 /* Make sure that we support the HMAC algorithm from the auth
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004007 * chunk.
4008 */
4009 if (!sctp_auth_asoc_verify_hmac_id(asoc, auth_hdr->hmac_id))
4010 return SCTP_IERROR_AUTH_BAD_HMAC;
4011
4012 /* Make sure that the provided shared key identifier has been
4013 * configured
4014 */
4015 key_id = ntohs(auth_hdr->shkey_id);
4016 if (key_id != asoc->active_key_id && !sctp_auth_get_shkey(asoc, key_id))
4017 return SCTP_IERROR_AUTH_BAD_KEYID;
4018
4019
4020 /* Make sure that the length of the signature matches what
4021 * we expect.
4022 */
4023 sig_len = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_auth_chunk_t);
4024 hmac = sctp_auth_get_hmac(ntohs(auth_hdr->hmac_id));
4025 if (sig_len != hmac->hmac_len)
4026 return SCTP_IERROR_PROTO_VIOLATION;
4027
4028 /* Now that we've done validation checks, we can compute and
4029 * verify the hmac. The steps involved are:
4030 * 1. Save the digest from the chunk.
4031 * 2. Zero out the digest in the chunk.
4032 * 3. Compute the new digest
4033 * 4. Compare saved and new digests.
4034 */
4035 digest = auth_hdr->hmac;
4036 skb_pull(chunk->skb, sig_len);
4037
4038 save_digest = kmemdup(digest, sig_len, GFP_ATOMIC);
4039 if (!save_digest)
4040 goto nomem;
4041
4042 memset(digest, 0, sig_len);
4043
4044 sctp_auth_calculate_hmac(asoc, chunk->skb,
4045 (struct sctp_auth_chunk *)chunk->chunk_hdr,
4046 GFP_ATOMIC);
4047
4048 /* Discard the packet if the digests do not match */
4049 if (memcmp(save_digest, digest, sig_len)) {
4050 kfree(save_digest);
4051 return SCTP_IERROR_BAD_SIG;
4052 }
4053
4054 kfree(save_digest);
4055 chunk->auth = 1;
4056
4057 return SCTP_IERROR_NO_ERROR;
4058nomem:
4059 return SCTP_IERROR_NOMEM;
4060}
4061
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004062sctp_disposition_t sctp_sf_eat_auth(struct net *net,
4063 const struct sctp_endpoint *ep,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004064 const struct sctp_association *asoc,
4065 const sctp_subtype_t type,
4066 void *arg,
4067 sctp_cmd_seq_t *commands)
4068{
4069 struct sctp_authhdr *auth_hdr;
4070 struct sctp_chunk *chunk = arg;
4071 struct sctp_chunk *err_chunk;
4072 sctp_ierror_t error;
4073
Wei Yongjund2f19fa2008-02-05 03:02:26 -08004074 /* Make sure that the peer has AUTH capable */
4075 if (!asoc->peer.auth_capable)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004076 return sctp_sf_unk_chunk(net, ep, asoc, type, arg, commands);
Wei Yongjund2f19fa2008-02-05 03:02:26 -08004077
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004078 if (!sctp_vtag_verify(chunk, asoc)) {
4079 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG,
4080 SCTP_NULL());
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004081 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004082 }
4083
4084 /* Make sure that the AUTH chunk has valid length. */
4085 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_auth_chunk)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004086 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004087 commands);
4088
4089 auth_hdr = (struct sctp_authhdr *)chunk->skb->data;
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004090 error = sctp_sf_authenticate(net, ep, asoc, type, chunk);
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004091 switch (error) {
Joe Perches7fd71b12011-07-01 09:43:11 +00004092 case SCTP_IERROR_AUTH_BAD_HMAC:
4093 /* Generate the ERROR chunk and discard the rest
4094 * of the packet
4095 */
4096 err_chunk = sctp_make_op_error(asoc, chunk,
4097 SCTP_ERROR_UNSUP_HMAC,
4098 &auth_hdr->hmac_id,
4099 sizeof(__u16), 0);
4100 if (err_chunk) {
4101 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
4102 SCTP_CHUNK(err_chunk));
4103 }
4104 /* Fall Through */
4105 case SCTP_IERROR_AUTH_BAD_KEYID:
4106 case SCTP_IERROR_BAD_SIG:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004107 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Joe Perches7fd71b12011-07-01 09:43:11 +00004108
4109 case SCTP_IERROR_PROTO_VIOLATION:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004110 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Joe Perches7fd71b12011-07-01 09:43:11 +00004111 commands);
4112
4113 case SCTP_IERROR_NOMEM:
4114 return SCTP_DISPOSITION_NOMEM;
4115
4116 default: /* Prevent gcc warnings */
4117 break;
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004118 }
4119
Vlad Yasevich65b07e52007-09-16 19:34:00 -07004120 if (asoc->active_key_id != ntohs(auth_hdr->shkey_id)) {
4121 struct sctp_ulpevent *ev;
4122
4123 ev = sctp_ulpevent_make_authkey(asoc, ntohs(auth_hdr->shkey_id),
4124 SCTP_AUTH_NEWKEY, GFP_ATOMIC);
4125
4126 if (!ev)
4127 return -ENOMEM;
4128
4129 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
4130 SCTP_ULPEVENT(ev));
4131 }
4132
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004133 return SCTP_DISPOSITION_CONSUME;
4134}
4135
4136/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07004137 * Process an unknown chunk.
4138 *
4139 * Section: 3.2. Also, 2.1 in the implementor's guide.
4140 *
4141 * Chunk Types are encoded such that the highest-order two bits specify
4142 * the action that must be taken if the processing endpoint does not
4143 * recognize the Chunk Type.
4144 *
4145 * 00 - Stop processing this SCTP packet and discard it, do not process
4146 * any further chunks within it.
4147 *
4148 * 01 - Stop processing this SCTP packet and discard it, do not process
4149 * any further chunks within it, and report the unrecognized
4150 * chunk in an 'Unrecognized Chunk Type'.
4151 *
4152 * 10 - Skip this chunk and continue processing.
4153 *
4154 * 11 - Skip this chunk and continue processing, but report in an ERROR
4155 * Chunk using the 'Unrecognized Chunk Type' cause of error.
4156 *
4157 * The return value is the disposition of the chunk.
4158 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004159sctp_disposition_t sctp_sf_unk_chunk(struct net *net,
4160 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004161 const struct sctp_association *asoc,
4162 const sctp_subtype_t type,
4163 void *arg,
4164 sctp_cmd_seq_t *commands)
4165{
4166 struct sctp_chunk *unk_chunk = arg;
4167 struct sctp_chunk *err_chunk;
4168 sctp_chunkhdr_t *hdr;
4169
Daniel Borkmannbb333812013-06-28 19:49:40 +02004170 pr_debug("%s: processing unknown chunk id:%d\n", __func__, type.chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004171
4172 if (!sctp_vtag_verify(unk_chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004173 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004174
4175 /* Make sure that the chunk has a valid length.
4176 * Since we don't know the chunk type, we use a general
4177 * chunkhdr structure to make a comparison.
4178 */
4179 if (!sctp_chunk_length_valid(unk_chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004180 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004181 commands);
4182
4183 switch (type.chunk & SCTP_CID_ACTION_MASK) {
4184 case SCTP_CID_ACTION_DISCARD:
4185 /* Discard the packet. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004186 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004187 case SCTP_CID_ACTION_DISCARD_ERR:
Linus Torvalds1da177e2005-04-16 15:20:36 -07004188 /* Generate an ERROR chunk as response. */
4189 hdr = unk_chunk->chunk_hdr;
4190 err_chunk = sctp_make_op_error(asoc, unk_chunk,
4191 SCTP_ERROR_UNKNOWN_CHUNK, hdr,
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05004192 WORD_ROUND(ntohs(hdr->length)),
4193 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004194 if (err_chunk) {
4195 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
4196 SCTP_CHUNK(err_chunk));
4197 }
Vlad Yasevich2e3216c2008-06-19 16:08:18 -07004198
4199 /* Discard the packet. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004200 sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004201 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004202 case SCTP_CID_ACTION_SKIP:
4203 /* Skip the chunk. */
4204 return SCTP_DISPOSITION_DISCARD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004205 case SCTP_CID_ACTION_SKIP_ERR:
4206 /* Generate an ERROR chunk as response. */
4207 hdr = unk_chunk->chunk_hdr;
4208 err_chunk = sctp_make_op_error(asoc, unk_chunk,
4209 SCTP_ERROR_UNKNOWN_CHUNK, hdr,
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05004210 WORD_ROUND(ntohs(hdr->length)),
4211 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004212 if (err_chunk) {
4213 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
4214 SCTP_CHUNK(err_chunk));
4215 }
4216 /* Skip the chunk. */
4217 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004218 default:
4219 break;
4220 }
4221
4222 return SCTP_DISPOSITION_DISCARD;
4223}
4224
4225/*
4226 * Discard the chunk.
4227 *
4228 * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2
4229 * [Too numerous to mention...]
4230 * Verification Tag: No verification needed.
4231 * Inputs
4232 * (endpoint, asoc, chunk)
4233 *
4234 * Outputs
4235 * (asoc, reply_msg, msg_up, timers, counters)
4236 *
4237 * The return value is the disposition of the chunk.
4238 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004239sctp_disposition_t sctp_sf_discard_chunk(struct net *net,
4240 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004241 const struct sctp_association *asoc,
4242 const sctp_subtype_t type,
4243 void *arg,
4244 sctp_cmd_seq_t *commands)
4245{
Vlad Yasevichece25df2007-09-07 16:30:54 -04004246 struct sctp_chunk *chunk = arg;
4247
4248 /* Make sure that the chunk has a valid length.
4249 * Since we don't know the chunk type, we use a general
4250 * chunkhdr structure to make a comparison.
4251 */
4252 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004253 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004254 commands);
4255
Daniel Borkmannbb333812013-06-28 19:49:40 +02004256 pr_debug("%s: chunk:%d is discarded\n", __func__, type.chunk);
4257
Linus Torvalds1da177e2005-04-16 15:20:36 -07004258 return SCTP_DISPOSITION_DISCARD;
4259}
4260
4261/*
4262 * Discard the whole packet.
4263 *
4264 * Section: 8.4 2)
4265 *
4266 * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST
4267 * silently discard the OOTB packet and take no further action.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004268 *
4269 * Verification Tag: No verification necessary
4270 *
4271 * Inputs
4272 * (endpoint, asoc, chunk)
4273 *
4274 * Outputs
4275 * (asoc, reply_msg, msg_up, timers, counters)
4276 *
4277 * The return value is the disposition of the chunk.
4278 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004279sctp_disposition_t sctp_sf_pdiscard(struct net *net,
4280 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004281 const struct sctp_association *asoc,
4282 const sctp_subtype_t type,
4283 void *arg,
4284 sctp_cmd_seq_t *commands)
4285{
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004286 SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_DISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004287 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
4288
4289 return SCTP_DISPOSITION_CONSUME;
4290}
4291
4292
4293/*
4294 * The other end is violating protocol.
4295 *
4296 * Section: Not specified
4297 * Verification Tag: Not specified
4298 * Inputs
4299 * (endpoint, asoc, chunk)
4300 *
4301 * Outputs
4302 * (asoc, reply_msg, msg_up, timers, counters)
4303 *
4304 * We simply tag the chunk as a violation. The state machine will log
4305 * the violation and continue.
4306 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004307sctp_disposition_t sctp_sf_violation(struct net *net,
4308 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004309 const struct sctp_association *asoc,
4310 const sctp_subtype_t type,
4311 void *arg,
4312 sctp_cmd_seq_t *commands)
4313{
Vlad Yasevichece25df2007-09-07 16:30:54 -04004314 struct sctp_chunk *chunk = arg;
4315
4316 /* Make sure that the chunk has a valid length. */
4317 if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004318 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004319 commands);
4320
Linus Torvalds1da177e2005-04-16 15:20:36 -07004321 return SCTP_DISPOSITION_VIOLATION;
4322}
4323
Linus Torvalds1da177e2005-04-16 15:20:36 -07004324/*
Wei Yongjunaecedea2007-08-02 16:57:44 +08004325 * Common function to handle a protocol violation.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004326 */
Wei Yongjunaecedea2007-08-02 16:57:44 +08004327static sctp_disposition_t sctp_sf_abort_violation(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004328 struct net *net,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004329 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004330 const struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004331 void *arg,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004332 sctp_cmd_seq_t *commands,
4333 const __u8 *payload,
4334 const size_t paylen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004335{
Vlad Yasevichece25df2007-09-07 16:30:54 -04004336 struct sctp_packet *packet = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004337 struct sctp_chunk *chunk = arg;
4338 struct sctp_chunk *abort = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004339
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004340 /* SCTP-AUTH, Section 6.3:
4341 * It should be noted that if the receiver wants to tear
4342 * down an association in an authenticated way only, the
4343 * handling of malformed packets should not result in
4344 * tearing down the association.
4345 *
4346 * This means that if we only want to abort associations
4347 * in an authenticated way (i.e AUTH+ABORT), then we
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004348 * can't destroy this association just because the packet
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07004349 * was malformed.
4350 */
4351 if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc))
4352 goto discard;
4353
Jesper Juhl9abed242007-11-11 23:57:49 +01004354 /* Make the abort chunk. */
4355 abort = sctp_make_abort_violation(asoc, chunk, payload, paylen);
4356 if (!abort)
4357 goto nomem;
4358
Vlad Yasevichece25df2007-09-07 16:30:54 -04004359 if (asoc) {
Gui Jianfengf4ad85c2008-04-12 18:39:34 -07004360 /* Treat INIT-ACK as a special case during COOKIE-WAIT. */
4361 if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK &&
4362 !asoc->peer.i.init_tag) {
4363 sctp_initack_chunk_t *initack;
4364
4365 initack = (sctp_initack_chunk_t *)chunk->chunk_hdr;
4366 if (!sctp_chunk_length_valid(chunk,
4367 sizeof(sctp_initack_chunk_t)))
4368 abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T;
4369 else {
4370 unsigned int inittag;
4371
4372 inittag = ntohl(initack->init_hdr.init_tag);
4373 sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG,
4374 SCTP_U32(inittag));
4375 }
4376 }
4377
Vlad Yasevichece25df2007-09-07 16:30:54 -04004378 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004379 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004380
Vlad Yasevichece25df2007-09-07 16:30:54 -04004381 if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) {
4382 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
4383 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4384 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4385 SCTP_ERROR(ECONNREFUSED));
4386 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
4387 SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION));
4388 } else {
4389 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4390 SCTP_ERROR(ECONNABORTED));
4391 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
4392 SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004393 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Vlad Yasevichece25df2007-09-07 16:30:54 -04004394 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004395 } else {
Eric W. Biederman2ce95502012-08-06 08:43:06 +00004396 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Vlad Yasevichece25df2007-09-07 16:30:54 -04004397
4398 if (!packet)
4399 goto nomem_pkt;
4400
4401 if (sctp_test_T_bit(abort))
4402 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
4403
4404 abort->skb->sk = ep->base.sk;
4405
4406 sctp_packet_append_chunk(packet, abort);
4407
4408 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
4409 SCTP_PACKET(packet));
4410
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004411 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004412 }
4413
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004414 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09004415
Vlad Yasevich56eb82b2008-10-09 14:33:01 -07004416discard:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004417 sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004418 return SCTP_DISPOSITION_ABORT;
4419
Vlad Yasevichece25df2007-09-07 16:30:54 -04004420nomem_pkt:
4421 sctp_chunk_free(abort);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004422nomem:
4423 return SCTP_DISPOSITION_NOMEM;
4424}
4425
Wei Yongjunaecedea2007-08-02 16:57:44 +08004426/*
4427 * Handle a protocol violation when the chunk length is invalid.
Frederik Schwarzer025dfda2008-10-16 19:02:37 +02004428 * "Invalid" length is identified as smaller than the minimal length a
Wei Yongjunaecedea2007-08-02 16:57:44 +08004429 * given chunk can be. For example, a SACK chunk has invalid length
Frederik Schwarzer025dfda2008-10-16 19:02:37 +02004430 * if its length is set to be smaller than the size of sctp_sack_chunk_t.
Wei Yongjunaecedea2007-08-02 16:57:44 +08004431 *
4432 * We inform the other end by sending an ABORT with a Protocol Violation
4433 * error code.
4434 *
4435 * Section: Not specified
4436 * Verification Tag: Nothing to do
4437 * Inputs
4438 * (endpoint, asoc, chunk)
4439 *
4440 * Outputs
4441 * (reply_msg, msg_up, counters)
4442 *
4443 * Generate an ABORT chunk and terminate the association.
4444 */
4445static sctp_disposition_t sctp_sf_violation_chunklen(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004446 struct net *net,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004447 const struct sctp_endpoint *ep,
4448 const struct sctp_association *asoc,
4449 const sctp_subtype_t type,
4450 void *arg,
4451 sctp_cmd_seq_t *commands)
4452{
wangweidongcb3f8372013-12-23 12:16:50 +08004453 static const char err_str[] = "The following chunk had invalid length:";
Wei Yongjunaecedea2007-08-02 16:57:44 +08004454
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004455 return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004456 sizeof(err_str));
4457}
4458
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004459/*
4460 * Handle a protocol violation when the parameter length is invalid.
Shan Wei33c7cfd2011-04-18 19:11:01 +00004461 * If the length is smaller than the minimum length of a given parameter,
4462 * or accumulated length in multi parameters exceeds the end of the chunk,
4463 * the length is considered as invalid.
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004464 */
4465static sctp_disposition_t sctp_sf_violation_paramlen(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004466 struct net *net,
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004467 const struct sctp_endpoint *ep,
4468 const struct sctp_association *asoc,
4469 const sctp_subtype_t type,
Wei Yongjunba016672008-09-30 05:32:24 -07004470 void *arg, void *ext,
4471 sctp_cmd_seq_t *commands)
4472{
4473 struct sctp_chunk *chunk = arg;
4474 struct sctp_paramhdr *param = ext;
4475 struct sctp_chunk *abort = NULL;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004476
Wei Yongjunba016672008-09-30 05:32:24 -07004477 if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc))
4478 goto discard;
4479
4480 /* Make the abort chunk. */
4481 abort = sctp_make_violation_paramlen(asoc, chunk, param);
4482 if (!abort)
4483 goto nomem;
4484
4485 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004486 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Wei Yongjunba016672008-09-30 05:32:24 -07004487
4488 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4489 SCTP_ERROR(ECONNABORTED));
4490 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
4491 SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004492 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
4493 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
Wei Yongjunba016672008-09-30 05:32:24 -07004494
4495discard:
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004496 sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands);
Wei Yongjunba016672008-09-30 05:32:24 -07004497 return SCTP_DISPOSITION_ABORT;
4498nomem:
4499 return SCTP_DISPOSITION_NOMEM;
Wei Yongjun6f4c6182007-09-19 17:19:52 +08004500}
4501
Wei Yongjunaecedea2007-08-02 16:57:44 +08004502/* Handle a protocol violation when the peer trying to advance the
4503 * cumulative tsn ack to a point beyond the max tsn currently sent.
4504 *
4505 * We inform the other end by sending an ABORT with a Protocol Violation
4506 * error code.
4507 */
4508static sctp_disposition_t sctp_sf_violation_ctsn(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004509 struct net *net,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004510 const struct sctp_endpoint *ep,
4511 const struct sctp_association *asoc,
4512 const sctp_subtype_t type,
4513 void *arg,
4514 sctp_cmd_seq_t *commands)
4515{
wangweidongcb3f8372013-12-23 12:16:50 +08004516 static const char err_str[] = "The cumulative tsn ack beyond the max tsn currently sent:";
Wei Yongjunaecedea2007-08-02 16:57:44 +08004517
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004518 return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
Wei Yongjunaecedea2007-08-02 16:57:44 +08004519 sizeof(err_str));
4520}
4521
Vlad Yasevichece25df2007-09-07 16:30:54 -04004522/* Handle protocol violation of an invalid chunk bundling. For example,
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004523 * when we have an association and we receive bundled INIT-ACK, or
Vlad Yasevichece25df2007-09-07 16:30:54 -04004524 * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle"
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004525 * statement from the specs. Additionally, there might be an attacker
Vlad Yasevichece25df2007-09-07 16:30:54 -04004526 * on the path and we may not want to continue this communication.
4527 */
4528static sctp_disposition_t sctp_sf_violation_chunk(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004529 struct net *net,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004530 const struct sctp_endpoint *ep,
4531 const struct sctp_association *asoc,
4532 const sctp_subtype_t type,
4533 void *arg,
4534 sctp_cmd_seq_t *commands)
4535{
wangweidongcb3f8372013-12-23 12:16:50 +08004536 static const char err_str[] = "The following chunk violates protocol:";
Vlad Yasevichece25df2007-09-07 16:30:54 -04004537
4538 if (!asoc)
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004539 return sctp_sf_violation(net, ep, asoc, type, arg, commands);
Vlad Yasevichece25df2007-09-07 16:30:54 -04004540
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004541 return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
Vlad Yasevichece25df2007-09-07 16:30:54 -04004542 sizeof(err_str));
4543}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004544/***************************************************************************
4545 * These are the state functions for handling primitive (Section 10) events.
4546 ***************************************************************************/
4547/*
4548 * sctp_sf_do_prm_asoc
4549 *
4550 * Section: 10.1 ULP-to-SCTP
4551 * B) Associate
4552 *
4553 * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
4554 * outbound stream count)
4555 * -> association id [,destination transport addr list] [,outbound stream
4556 * count]
4557 *
4558 * This primitive allows the upper layer to initiate an association to a
4559 * specific peer endpoint.
4560 *
4561 * The peer endpoint shall be specified by one of the transport addresses
4562 * which defines the endpoint (see Section 1.4). If the local SCTP
4563 * instance has not been initialized, the ASSOCIATE is considered an
4564 * error.
4565 * [This is not relevant for the kernel implementation since we do all
4566 * initialization at boot time. It we hadn't initialized we wouldn't
4567 * get anywhere near this code.]
4568 *
4569 * An association id, which is a local handle to the SCTP association,
4570 * will be returned on successful establishment of the association. If
4571 * SCTP is not able to open an SCTP association with the peer endpoint,
4572 * an error is returned.
4573 * [In the kernel implementation, the struct sctp_association needs to
4574 * be created BEFORE causing this primitive to run.]
4575 *
4576 * Other association parameters may be returned, including the
4577 * complete destination transport addresses of the peer as well as the
4578 * outbound stream count of the local endpoint. One of the transport
4579 * address from the returned destination addresses will be selected by
4580 * the local endpoint as default primary path for sending SCTP packets
4581 * to this peer. The returned "destination transport addr list" can
4582 * be used by the ULP to change the default primary path or to force
4583 * sending a packet to a specific transport address. [All of this
4584 * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING
4585 * function.]
4586 *
4587 * Mandatory attributes:
4588 *
4589 * o local SCTP instance name - obtained from the INITIALIZE operation.
4590 * [This is the argument asoc.]
4591 * o destination transport addr - specified as one of the transport
4592 * addresses of the peer endpoint with which the association is to be
4593 * established.
4594 * [This is asoc->peer.active_path.]
4595 * o outbound stream count - the number of outbound streams the ULP
4596 * would like to open towards this peer endpoint.
4597 * [BUG: This is not currently implemented.]
4598 * Optional attributes:
4599 *
4600 * None.
4601 *
4602 * The return value is a disposition.
4603 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004604sctp_disposition_t sctp_sf_do_prm_asoc(struct net *net,
4605 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004606 const struct sctp_association *asoc,
4607 const sctp_subtype_t type,
4608 void *arg,
4609 sctp_cmd_seq_t *commands)
4610{
4611 struct sctp_chunk *repl;
wangweidong26ac8e52013-12-23 12:16:51 +08004612 struct sctp_association *my_asoc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004613
4614 /* The comment below says that we enter COOKIE-WAIT AFTER
4615 * sending the INIT, but that doesn't actually work in our
4616 * implementation...
4617 */
4618 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4619 SCTP_STATE(SCTP_STATE_COOKIE_WAIT));
4620
4621 /* RFC 2960 5.1 Normal Establishment of an Association
4622 *
4623 * A) "A" first sends an INIT chunk to "Z". In the INIT, "A"
4624 * must provide its Verification Tag (Tag_A) in the Initiate
4625 * Tag field. Tag_A SHOULD be a random number in the range of
4626 * 1 to 4294967295 (see 5.3.1 for Tag value selection). ...
4627 */
4628
4629 repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0);
4630 if (!repl)
4631 goto nomem;
4632
Daniel Borkmann405426f2013-06-14 18:24:05 +02004633 /* Choose transport for INIT. */
4634 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT,
4635 SCTP_CHUNK(repl));
4636
Linus Torvalds1da177e2005-04-16 15:20:36 -07004637 /* Cast away the const modifier, as we want to just
4638 * rerun it through as a sideffect.
4639 */
Vlad Yasevichab38fb02008-04-12 18:40:06 -07004640 my_asoc = (struct sctp_association *)asoc;
4641 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(my_asoc));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004642
4643 /* After sending the INIT, "A" starts the T1-init timer and
4644 * enters the COOKIE-WAIT state.
4645 */
4646 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
4647 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4648 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
4649 return SCTP_DISPOSITION_CONSUME;
4650
4651nomem:
4652 return SCTP_DISPOSITION_NOMEM;
4653}
4654
4655/*
4656 * Process the SEND primitive.
4657 *
4658 * Section: 10.1 ULP-to-SCTP
4659 * E) Send
4660 *
4661 * Format: SEND(association id, buffer address, byte count [,context]
4662 * [,stream id] [,life time] [,destination transport address]
4663 * [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
4664 * -> result
4665 *
4666 * This is the main method to send user data via SCTP.
4667 *
4668 * Mandatory attributes:
4669 *
4670 * o association id - local handle to the SCTP association
4671 *
4672 * o buffer address - the location where the user message to be
4673 * transmitted is stored;
4674 *
4675 * o byte count - The size of the user data in number of bytes;
4676 *
4677 * Optional attributes:
4678 *
4679 * o context - an optional 32 bit integer that will be carried in the
4680 * sending failure notification to the ULP if the transportation of
4681 * this User Message fails.
4682 *
4683 * o stream id - to indicate which stream to send the data on. If not
4684 * specified, stream 0 will be used.
4685 *
4686 * o life time - specifies the life time of the user data. The user data
4687 * will not be sent by SCTP after the life time expires. This
4688 * parameter can be used to avoid efforts to transmit stale
4689 * user messages. SCTP notifies the ULP if the data cannot be
4690 * initiated to transport (i.e. sent to the destination via SCTP's
4691 * send primitive) within the life time variable. However, the
4692 * user data will be transmitted if SCTP has attempted to transmit a
4693 * chunk before the life time expired.
4694 *
4695 * o destination transport address - specified as one of the destination
4696 * transport addresses of the peer endpoint to which this packet
4697 * should be sent. Whenever possible, SCTP should use this destination
4698 * transport address for sending the packets, instead of the current
4699 * primary path.
4700 *
4701 * o unorder flag - this flag, if present, indicates that the user
4702 * would like the data delivered in an unordered fashion to the peer
4703 * (i.e., the U flag is set to 1 on all DATA chunks carrying this
4704 * message).
4705 *
4706 * o no-bundle flag - instructs SCTP not to bundle this user data with
4707 * other outbound DATA chunks. SCTP MAY still bundle even when
4708 * this flag is present, when faced with network congestion.
4709 *
4710 * o payload protocol-id - A 32 bit unsigned integer that is to be
4711 * passed to the peer indicating the type of payload protocol data
4712 * being transmitted. This value is passed as opaque data by SCTP.
4713 *
4714 * The return value is the disposition.
4715 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004716sctp_disposition_t sctp_sf_do_prm_send(struct net *net,
4717 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004718 const struct sctp_association *asoc,
4719 const sctp_subtype_t type,
4720 void *arg,
4721 sctp_cmd_seq_t *commands)
4722{
Vlad Yasevich9c5c62b2009-08-10 13:51:03 -04004723 struct sctp_datamsg *msg = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004724
Vlad Yasevich9c5c62b2009-08-10 13:51:03 -04004725 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_MSG, SCTP_DATAMSG(msg));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004726 return SCTP_DISPOSITION_CONSUME;
4727}
4728
4729/*
4730 * Process the SHUTDOWN primitive.
4731 *
4732 * Section: 10.1:
4733 * C) Shutdown
4734 *
4735 * Format: SHUTDOWN(association id)
4736 * -> result
4737 *
4738 * Gracefully closes an association. Any locally queued user data
4739 * will be delivered to the peer. The association will be terminated only
4740 * after the peer acknowledges all the SCTP packets sent. A success code
4741 * will be returned on successful termination of the association. If
4742 * attempting to terminate the association results in a failure, an error
4743 * code shall be returned.
4744 *
4745 * Mandatory attributes:
4746 *
4747 * o association id - local handle to the SCTP association
4748 *
4749 * Optional attributes:
4750 *
4751 * None.
4752 *
4753 * The return value is the disposition.
4754 */
4755sctp_disposition_t sctp_sf_do_9_2_prm_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004756 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004757 const struct sctp_endpoint *ep,
4758 const struct sctp_association *asoc,
4759 const sctp_subtype_t type,
4760 void *arg,
4761 sctp_cmd_seq_t *commands)
4762{
4763 int disposition;
4764
4765 /* From 9.2 Shutdown of an Association
4766 * Upon receipt of the SHUTDOWN primitive from its upper
4767 * layer, the endpoint enters SHUTDOWN-PENDING state and
4768 * remains there until all outstanding data has been
4769 * acknowledged by its peer. The endpoint accepts no new data
4770 * from its upper layer, but retransmits data to the far end
4771 * if necessary to fill gaps.
4772 */
4773 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4774 SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING));
4775
Linus Torvalds1da177e2005-04-16 15:20:36 -07004776 disposition = SCTP_DISPOSITION_CONSUME;
4777 if (sctp_outq_is_empty(&asoc->outqueue)) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004778 disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004779 arg, commands);
4780 }
4781 return disposition;
4782}
4783
4784/*
4785 * Process the ABORT primitive.
4786 *
4787 * Section: 10.1:
4788 * C) Abort
4789 *
4790 * Format: Abort(association id [, cause code])
4791 * -> result
4792 *
4793 * Ungracefully closes an association. Any locally queued user data
4794 * will be discarded and an ABORT chunk is sent to the peer. A success code
4795 * will be returned on successful abortion of the association. If
4796 * attempting to abort the association results in a failure, an error
4797 * code shall be returned.
4798 *
4799 * Mandatory attributes:
4800 *
4801 * o association id - local handle to the SCTP association
4802 *
4803 * Optional attributes:
4804 *
4805 * o cause code - reason of the abort to be passed to the peer
4806 *
4807 * None.
4808 *
4809 * The return value is the disposition.
4810 */
4811sctp_disposition_t sctp_sf_do_9_1_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004812 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004813 const struct sctp_endpoint *ep,
4814 const struct sctp_association *asoc,
4815 const sctp_subtype_t type,
4816 void *arg,
4817 sctp_cmd_seq_t *commands)
4818{
4819 /* From 9.1 Abort of an Association
4820 * Upon receipt of the ABORT primitive from its upper
4821 * layer, the endpoint enters CLOSED state and
4822 * discard all outstanding data has been
4823 * acknowledged by its peer. The endpoint accepts no new data
4824 * from its upper layer, but retransmits data to the far end
4825 * if necessary to fill gaps.
4826 */
Sridhar Samudralac164a9b2006-08-22 11:50:39 -07004827 struct sctp_chunk *abort = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004828 sctp_disposition_t retval;
4829
4830 retval = SCTP_DISPOSITION_CONSUME;
4831
Sridhar Samudralac164a9b2006-08-22 11:50:39 -07004832 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004833
4834 /* Even if we can't send the ABORT due to low memory delete the
4835 * TCB. This is a departure from our typical NOMEM handling.
4836 */
4837
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07004838 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4839 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004840 /* Delete the established association. */
4841 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08004842 SCTP_PERR(SCTP_ERROR_USER_ABORT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004843
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004844 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
4845 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004846
4847 return retval;
4848}
4849
4850/* We tried an illegal operation on an association which is closed. */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004851sctp_disposition_t sctp_sf_error_closed(struct net *net,
4852 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004853 const struct sctp_association *asoc,
4854 const sctp_subtype_t type,
4855 void *arg,
4856 sctp_cmd_seq_t *commands)
4857{
4858 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL));
4859 return SCTP_DISPOSITION_CONSUME;
4860}
4861
4862/* We tried an illegal operation on an association which is shutting
4863 * down.
4864 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004865sctp_disposition_t sctp_sf_error_shutdown(struct net *net,
4866 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004867 const struct sctp_association *asoc,
4868 const sctp_subtype_t type,
4869 void *arg,
4870 sctp_cmd_seq_t *commands)
4871{
4872 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR,
4873 SCTP_ERROR(-ESHUTDOWN));
4874 return SCTP_DISPOSITION_CONSUME;
4875}
4876
4877/*
4878 * sctp_cookie_wait_prm_shutdown
4879 *
4880 * Section: 4 Note: 2
4881 * Verification Tag:
4882 * Inputs
4883 * (endpoint, asoc)
4884 *
4885 * The RFC does not explicitly address this issue, but is the route through the
4886 * state table when someone issues a shutdown while in COOKIE_WAIT state.
4887 *
4888 * Outputs
4889 * (timers)
4890 */
4891sctp_disposition_t sctp_sf_cookie_wait_prm_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004892 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004893 const struct sctp_endpoint *ep,
4894 const struct sctp_association *asoc,
4895 const sctp_subtype_t type,
4896 void *arg,
4897 sctp_cmd_seq_t *commands)
4898{
4899 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
4900 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4901
4902 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4903 SCTP_STATE(SCTP_STATE_CLOSED));
4904
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004905 SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004906
4907 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
4908
4909 return SCTP_DISPOSITION_DELETE_TCB;
4910}
4911
4912/*
4913 * sctp_cookie_echoed_prm_shutdown
4914 *
4915 * Section: 4 Note: 2
4916 * Verification Tag:
4917 * Inputs
4918 * (endpoint, asoc)
4919 *
4920 * The RFC does not explcitly address this issue, but is the route through the
4921 * state table when someone issues a shutdown while in COOKIE_ECHOED state.
4922 *
4923 * Outputs
4924 * (timers)
4925 */
4926sctp_disposition_t sctp_sf_cookie_echoed_prm_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004927 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004928 const struct sctp_endpoint *ep,
4929 const struct sctp_association *asoc,
4930 const sctp_subtype_t type,
4931 void *arg, sctp_cmd_seq_t *commands)
4932{
4933 /* There is a single T1 timer, so we should be able to use
4934 * common function with the COOKIE-WAIT state.
4935 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004936 return sctp_sf_cookie_wait_prm_shutdown(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004937}
4938
4939/*
4940 * sctp_sf_cookie_wait_prm_abort
4941 *
4942 * Section: 4 Note: 2
4943 * Verification Tag:
4944 * Inputs
4945 * (endpoint, asoc)
4946 *
4947 * The RFC does not explicitly address this issue, but is the route through the
4948 * state table when someone issues an abort while in COOKIE_WAIT state.
4949 *
4950 * Outputs
4951 * (timers)
4952 */
4953sctp_disposition_t sctp_sf_cookie_wait_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00004954 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004955 const struct sctp_endpoint *ep,
4956 const struct sctp_association *asoc,
4957 const sctp_subtype_t type,
4958 void *arg,
4959 sctp_cmd_seq_t *commands)
4960{
Sridhar Samudralac164a9b2006-08-22 11:50:39 -07004961 struct sctp_chunk *abort = arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004962 sctp_disposition_t retval;
4963
4964 /* Stop T1-init timer */
4965 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
4966 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
4967 retval = SCTP_DISPOSITION_CONSUME;
4968
Sridhar Samudralac164a9b2006-08-22 11:50:39 -07004969 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004970
4971 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
4972 SCTP_STATE(SCTP_STATE_CLOSED));
4973
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00004974 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004975
4976 /* Even if we can't send the ABORT due to low memory delete the
4977 * TCB. This is a departure from our typical NOMEM handling.
4978 */
4979
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07004980 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
4981 SCTP_ERROR(ECONNREFUSED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004982 /* Delete the established association. */
4983 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08004984 SCTP_PERR(SCTP_ERROR_USER_ABORT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07004985
4986 return retval;
4987}
4988
4989/*
4990 * sctp_sf_cookie_echoed_prm_abort
4991 *
4992 * Section: 4 Note: 3
4993 * Verification Tag:
4994 * Inputs
4995 * (endpoint, asoc)
4996 *
4997 * The RFC does not explcitly address this issue, but is the route through the
4998 * state table when someone issues an abort while in COOKIE_ECHOED state.
4999 *
5000 * Outputs
5001 * (timers)
5002 */
5003sctp_disposition_t sctp_sf_cookie_echoed_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005004 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005005 const struct sctp_endpoint *ep,
5006 const struct sctp_association *asoc,
5007 const sctp_subtype_t type,
5008 void *arg,
5009 sctp_cmd_seq_t *commands)
5010{
5011 /* There is a single T1 timer, so we should be able to use
5012 * common function with the COOKIE-WAIT state.
5013 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005014 return sctp_sf_cookie_wait_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005015}
5016
5017/*
5018 * sctp_sf_shutdown_pending_prm_abort
5019 *
5020 * Inputs
5021 * (endpoint, asoc)
5022 *
5023 * The RFC does not explicitly address this issue, but is the route through the
5024 * state table when someone issues an abort while in SHUTDOWN-PENDING state.
5025 *
5026 * Outputs
5027 * (timers)
5028 */
5029sctp_disposition_t sctp_sf_shutdown_pending_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005030 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005031 const struct sctp_endpoint *ep,
5032 const struct sctp_association *asoc,
5033 const sctp_subtype_t type,
5034 void *arg,
5035 sctp_cmd_seq_t *commands)
5036{
5037 /* Stop the T5-shutdown guard timer. */
5038 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5039 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5040
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005041 return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005042}
5043
5044/*
5045 * sctp_sf_shutdown_sent_prm_abort
5046 *
5047 * Inputs
5048 * (endpoint, asoc)
5049 *
5050 * The RFC does not explicitly address this issue, but is the route through the
5051 * state table when someone issues an abort while in SHUTDOWN-SENT state.
5052 *
5053 * Outputs
5054 * (timers)
5055 */
5056sctp_disposition_t sctp_sf_shutdown_sent_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005057 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005058 const struct sctp_endpoint *ep,
5059 const struct sctp_association *asoc,
5060 const sctp_subtype_t type,
5061 void *arg,
5062 sctp_cmd_seq_t *commands)
5063{
5064 /* Stop the T2-shutdown timer. */
5065 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5066 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5067
5068 /* Stop the T5-shutdown guard timer. */
5069 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5070 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5071
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005072 return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005073}
5074
5075/*
5076 * sctp_sf_cookie_echoed_prm_abort
5077 *
5078 * Inputs
5079 * (endpoint, asoc)
5080 *
5081 * The RFC does not explcitly address this issue, but is the route through the
5082 * state table when someone issues an abort while in COOKIE_ECHOED state.
5083 *
5084 * Outputs
5085 * (timers)
5086 */
5087sctp_disposition_t sctp_sf_shutdown_ack_sent_prm_abort(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005088 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005089 const struct sctp_endpoint *ep,
5090 const struct sctp_association *asoc,
5091 const sctp_subtype_t type,
5092 void *arg,
5093 sctp_cmd_seq_t *commands)
5094{
5095 /* The same T2 timer, so we should be able to use
5096 * common function with the SHUTDOWN-SENT state.
5097 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005098 return sctp_sf_shutdown_sent_prm_abort(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005099}
5100
5101/*
5102 * Process the REQUESTHEARTBEAT primitive
5103 *
5104 * 10.1 ULP-to-SCTP
5105 * J) Request Heartbeat
5106 *
5107 * Format: REQUESTHEARTBEAT(association id, destination transport address)
5108 *
5109 * -> result
5110 *
5111 * Instructs the local endpoint to perform a HeartBeat on the specified
5112 * destination transport address of the given association. The returned
5113 * result should indicate whether the transmission of the HEARTBEAT
5114 * chunk to the destination address is successful.
5115 *
5116 * Mandatory attributes:
5117 *
5118 * o association id - local handle to the SCTP association
5119 *
5120 * o destination transport address - the transport address of the
5121 * association on which a heartbeat should be issued.
5122 */
5123sctp_disposition_t sctp_sf_do_prm_requestheartbeat(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005124 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005125 const struct sctp_endpoint *ep,
5126 const struct sctp_association *asoc,
5127 const sctp_subtype_t type,
5128 void *arg,
5129 sctp_cmd_seq_t *commands)
5130{
Vlad Yasevichfb785252007-03-19 17:02:03 -07005131 if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type,
5132 (struct sctp_transport *)arg, commands))
5133 return SCTP_DISPOSITION_NOMEM;
5134
5135 /*
5136 * RFC 2960 (bis), section 8.3
5137 *
5138 * D) Request an on-demand HEARTBEAT on a specific destination
5139 * transport address of a given association.
5140 *
5141 * The endpoint should increment the respective error counter of
5142 * the destination transport address each time a HEARTBEAT is sent
5143 * to that address and not acknowledged within one RTO.
5144 *
5145 */
Vlad Yasevich7e990132009-03-02 09:46:14 +00005146 sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT,
Vlad Yasevichfb785252007-03-19 17:02:03 -07005147 SCTP_TRANSPORT(arg));
5148 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005149}
5150
5151/*
5152 * ADDIP Section 4.1 ASCONF Chunk Procedures
5153 * When an endpoint has an ASCONF signaled change to be sent to the
5154 * remote endpoint it should do A1 to A9
5155 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005156sctp_disposition_t sctp_sf_do_prm_asconf(struct net *net,
5157 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005158 const struct sctp_association *asoc,
5159 const sctp_subtype_t type,
5160 void *arg,
5161 sctp_cmd_seq_t *commands)
5162{
5163 struct sctp_chunk *chunk = arg;
5164
5165 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk));
5166 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
5167 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
5168 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk));
5169 return SCTP_DISPOSITION_CONSUME;
5170}
5171
5172/*
5173 * Ignore the primitive event
5174 *
5175 * The return value is the disposition of the primitive.
5176 */
5177sctp_disposition_t sctp_sf_ignore_primitive(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005178 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005179 const struct sctp_endpoint *ep,
5180 const struct sctp_association *asoc,
5181 const sctp_subtype_t type,
5182 void *arg,
5183 sctp_cmd_seq_t *commands)
5184{
Daniel Borkmannbb333812013-06-28 19:49:40 +02005185 pr_debug("%s: primitive type:%d is ignored\n", __func__,
5186 type.primitive);
5187
Linus Torvalds1da177e2005-04-16 15:20:36 -07005188 return SCTP_DISPOSITION_DISCARD;
5189}
5190
5191/***************************************************************************
5192 * These are the state functions for the OTHER events.
5193 ***************************************************************************/
5194
5195/*
Wei Yongjune1cdd552011-04-17 17:29:03 +00005196 * When the SCTP stack has no more user data to send or retransmit, this
5197 * notification is given to the user. Also, at the time when a user app
5198 * subscribes to this event, if there is no data to be sent or
5199 * retransmit, the stack will immediately send up this notification.
5200 */
5201sctp_disposition_t sctp_sf_do_no_pending_tsn(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005202 struct net *net,
Wei Yongjune1cdd552011-04-17 17:29:03 +00005203 const struct sctp_endpoint *ep,
5204 const struct sctp_association *asoc,
5205 const sctp_subtype_t type,
5206 void *arg,
5207 sctp_cmd_seq_t *commands)
5208{
5209 struct sctp_ulpevent *event;
5210
5211 event = sctp_ulpevent_make_sender_dry_event(asoc, GFP_ATOMIC);
5212 if (!event)
5213 return SCTP_DISPOSITION_NOMEM;
5214
5215 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event));
5216
5217 return SCTP_DISPOSITION_CONSUME;
5218}
5219
5220/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07005221 * Start the shutdown negotiation.
5222 *
5223 * From Section 9.2:
5224 * Once all its outstanding data has been acknowledged, the endpoint
5225 * shall send a SHUTDOWN chunk to its peer including in the Cumulative
5226 * TSN Ack field the last sequential TSN it has received from the peer.
5227 * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT
5228 * state. If the timer expires, the endpoint must re-send the SHUTDOWN
5229 * with the updated last sequential TSN received from its peer.
5230 *
5231 * The return value is the disposition.
5232 */
5233sctp_disposition_t sctp_sf_do_9_2_start_shutdown(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005234 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005235 const struct sctp_endpoint *ep,
5236 const struct sctp_association *asoc,
5237 const sctp_subtype_t type,
5238 void *arg,
5239 sctp_cmd_seq_t *commands)
5240{
5241 struct sctp_chunk *reply;
5242
5243 /* Once all its outstanding data has been acknowledged, the
5244 * endpoint shall send a SHUTDOWN chunk to its peer including
5245 * in the Cumulative TSN Ack field the last sequential TSN it
5246 * has received from the peer.
5247 */
5248 reply = sctp_make_shutdown(asoc, NULL);
5249 if (!reply)
5250 goto nomem;
5251
5252 /* Set the transport for the SHUTDOWN chunk and the timeout for the
5253 * T2-shutdown timer.
5254 */
5255 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
5256
5257 /* It shall then start the T2-shutdown timer */
5258 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
5259 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5260
Wei Yongjun536428a2008-09-05 08:55:26 +08005261 /* RFC 4960 Section 9.2
5262 * The sender of the SHUTDOWN MAY also start an overall guard timer
5263 * 'T5-shutdown-guard' to bound the overall time for shutdown sequence.
5264 */
Thomas Graff8d96052011-07-07 00:28:35 +00005265 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
Wei Yongjun536428a2008-09-05 08:55:26 +08005266 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5267
Neil Horman9f70f462013-12-10 06:48:15 -05005268 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE])
Linus Torvalds1da177e2005-04-16 15:20:36 -07005269 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5270 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
5271
5272 /* and enter the SHUTDOWN-SENT state. */
5273 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
5274 SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT));
5275
5276 /* sctp-implguide 2.10 Issues with Heartbeating and failover
5277 *
5278 * HEARTBEAT ... is discontinued after sending either SHUTDOWN
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09005279 * or SHUTDOWN-ACK.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005280 */
5281 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL());
5282
5283 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
5284
5285 return SCTP_DISPOSITION_CONSUME;
5286
5287nomem:
5288 return SCTP_DISPOSITION_NOMEM;
5289}
5290
5291/*
5292 * Generate a SHUTDOWN ACK now that everything is SACK'd.
5293 *
5294 * From Section 9.2:
5295 *
5296 * If it has no more outstanding DATA chunks, the SHUTDOWN receiver
5297 * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own,
5298 * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the
5299 * endpoint must re-send the SHUTDOWN ACK.
5300 *
5301 * The return value is the disposition.
5302 */
5303sctp_disposition_t sctp_sf_do_9_2_shutdown_ack(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005304 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005305 const struct sctp_endpoint *ep,
5306 const struct sctp_association *asoc,
5307 const sctp_subtype_t type,
5308 void *arg,
5309 sctp_cmd_seq_t *commands)
5310{
5311 struct sctp_chunk *chunk = (struct sctp_chunk *) arg;
5312 struct sctp_chunk *reply;
5313
5314 /* There are 2 ways of getting here:
5315 * 1) called in response to a SHUTDOWN chunk
5316 * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued.
5317 *
5318 * For the case (2), the arg parameter is set to NULL. We need
5319 * to check that we have a chunk before accessing it's fields.
5320 */
5321 if (chunk) {
5322 if (!sctp_vtag_verify(chunk, asoc))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005323 return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005324
5325 /* Make sure that the SHUTDOWN chunk has a valid length. */
5326 if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk_t)))
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005327 return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005328 commands);
5329 }
5330
5331 /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver
5332 * shall send a SHUTDOWN ACK ...
5333 */
5334 reply = sctp_make_shutdown_ack(asoc, chunk);
5335 if (!reply)
5336 goto nomem;
5337
5338 /* Set the transport for the SHUTDOWN ACK chunk and the timeout for
5339 * the T2-shutdown timer.
5340 */
5341 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
5342
5343 /* and start/restart a T2-shutdown timer of its own, */
5344 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
5345 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5346
Neil Horman9f70f462013-12-10 06:48:15 -05005347 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE])
Linus Torvalds1da177e2005-04-16 15:20:36 -07005348 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5349 SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));
5350
5351 /* Enter the SHUTDOWN-ACK-SENT state. */
5352 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
5353 SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT));
5354
5355 /* sctp-implguide 2.10 Issues with Heartbeating and failover
5356 *
5357 * HEARTBEAT ... is discontinued after sending either SHUTDOWN
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09005358 * or SHUTDOWN-ACK.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005359 */
5360 sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL());
5361
5362 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
5363
5364 return SCTP_DISPOSITION_CONSUME;
5365
5366nomem:
5367 return SCTP_DISPOSITION_NOMEM;
5368}
5369
5370/*
5371 * Ignore the event defined as other
5372 *
5373 * The return value is the disposition of the event.
5374 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005375sctp_disposition_t sctp_sf_ignore_other(struct net *net,
5376 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005377 const struct sctp_association *asoc,
5378 const sctp_subtype_t type,
5379 void *arg,
5380 sctp_cmd_seq_t *commands)
5381{
Daniel Borkmannbb333812013-06-28 19:49:40 +02005382 pr_debug("%s: the event other type:%d is ignored\n",
5383 __func__, type.other);
5384
Linus Torvalds1da177e2005-04-16 15:20:36 -07005385 return SCTP_DISPOSITION_DISCARD;
5386}
5387
5388/************************************************************
5389 * These are the state functions for handling timeout events.
5390 ************************************************************/
5391
5392/*
5393 * RTX Timeout
5394 *
5395 * Section: 6.3.3 Handle T3-rtx Expiration
5396 *
5397 * Whenever the retransmission timer T3-rtx expires for a destination
5398 * address, do the following:
5399 * [See below]
5400 *
5401 * The return value is the disposition of the chunk.
5402 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005403sctp_disposition_t sctp_sf_do_6_3_3_rtx(struct net *net,
5404 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005405 const struct sctp_association *asoc,
5406 const sctp_subtype_t type,
5407 void *arg,
5408 sctp_cmd_seq_t *commands)
5409{
5410 struct sctp_transport *transport = arg;
5411
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005412 SCTP_INC_STATS(net, SCTP_MIB_T3_RTX_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005413
Linus Torvalds1da177e2005-04-16 15:20:36 -07005414 if (asoc->overall_error_count >= asoc->max_retrans) {
Thomas Graff8d96052011-07-07 00:28:35 +00005415 if (asoc->state == SCTP_STATE_SHUTDOWN_PENDING) {
5416 /*
5417 * We are here likely because the receiver had its rwnd
5418 * closed for a while and we have not been able to
5419 * transmit the locally queued data within the maximum
5420 * retransmission attempts limit. Start the T5
5421 * shutdown guard timer to give the receiver one last
5422 * chance and some additional time to recover before
5423 * aborting.
5424 */
5425 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START_ONCE,
5426 SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));
5427 } else {
5428 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5429 SCTP_ERROR(ETIMEDOUT));
5430 /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
5431 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
5432 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005433 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5434 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Thomas Graff8d96052011-07-07 00:28:35 +00005435 return SCTP_DISPOSITION_DELETE_TCB;
5436 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005437 }
5438
5439 /* E1) For the destination address for which the timer
5440 * expires, adjust its ssthresh with rules defined in Section
5441 * 7.2.3 and set the cwnd <- MTU.
5442 */
5443
5444 /* E2) For the destination address for which the timer
5445 * expires, set RTO <- RTO * 2 ("back off the timer"). The
5446 * maximum value discussed in rule C7 above (RTO.max) may be
5447 * used to provide an upper bound to this doubling operation.
5448 */
5449
5450 /* E3) Determine how many of the earliest (i.e., lowest TSN)
5451 * outstanding DATA chunks for the address for which the
5452 * T3-rtx has expired will fit into a single packet, subject
5453 * to the MTU constraint for the path corresponding to the
5454 * destination transport address to which the retransmission
5455 * is being sent (this may be different from the address for
5456 * which the timer expires [see Section 6.4]). Call this
5457 * value K. Bundle and retransmit those K DATA chunks in a
5458 * single packet to the destination endpoint.
5459 *
5460 * Note: Any DATA chunks that were sent to the address for
5461 * which the T3-rtx timer expired but did not fit in one MTU
5462 * (rule E3 above), should be marked for retransmission and
5463 * sent as soon as cwnd allows (normally when a SACK arrives).
5464 */
5465
Linus Torvalds1da177e2005-04-16 15:20:36 -07005466 /* Do some failure management (Section 8.2). */
5467 sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport));
5468
Vlad Yasevich1845a572007-02-21 02:06:19 -08005469 /* NB: Rules E4 and F1 are implicit in R1. */
5470 sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport));
5471
Linus Torvalds1da177e2005-04-16 15:20:36 -07005472 return SCTP_DISPOSITION_CONSUME;
5473}
5474
5475/*
5476 * Generate delayed SACK on timeout
5477 *
5478 * Section: 6.2 Acknowledgement on Reception of DATA Chunks
5479 *
5480 * The guidelines on delayed acknowledgement algorithm specified in
5481 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an
5482 * acknowledgement SHOULD be generated for at least every second packet
5483 * (not every second DATA chunk) received, and SHOULD be generated
5484 * within 200 ms of the arrival of any unacknowledged DATA chunk. In
5485 * some situations it may be beneficial for an SCTP transmitter to be
5486 * more conservative than the algorithms detailed in this document
5487 * allow. However, an SCTP transmitter MUST NOT be more aggressive than
5488 * the following algorithms allow.
5489 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005490sctp_disposition_t sctp_sf_do_6_2_sack(struct net *net,
5491 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005492 const struct sctp_association *asoc,
5493 const sctp_subtype_t type,
5494 void *arg,
5495 sctp_cmd_seq_t *commands)
5496{
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005497 SCTP_INC_STATS(net, SCTP_MIB_DELAY_SACK_EXPIREDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005498 sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
5499 return SCTP_DISPOSITION_CONSUME;
5500}
5501
5502/*
Frank Filz3f7a87d2005-06-20 13:14:57 -07005503 * sctp_sf_t1_init_timer_expire
Linus Torvalds1da177e2005-04-16 15:20:36 -07005504 *
5505 * Section: 4 Note: 2
5506 * Verification Tag:
5507 * Inputs
5508 * (endpoint, asoc)
5509 *
5510 * RFC 2960 Section 4 Notes
5511 * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT
5512 * and re-start the T1-init timer without changing state. This MUST
5513 * be repeated up to 'Max.Init.Retransmits' times. After that, the
5514 * endpoint MUST abort the initialization process and report the
5515 * error to SCTP user.
5516 *
Frank Filz3f7a87d2005-06-20 13:14:57 -07005517 * Outputs
5518 * (timers, events)
5519 *
5520 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005521sctp_disposition_t sctp_sf_t1_init_timer_expire(struct net *net,
5522 const struct sctp_endpoint *ep,
Frank Filz3f7a87d2005-06-20 13:14:57 -07005523 const struct sctp_association *asoc,
5524 const sctp_subtype_t type,
5525 void *arg,
5526 sctp_cmd_seq_t *commands)
5527{
5528 struct sctp_chunk *repl = NULL;
5529 struct sctp_bind_addr *bp;
5530 int attempts = asoc->init_err_counter + 1;
5531
Daniel Borkmannbb333812013-06-28 19:49:40 +02005532 pr_debug("%s: timer T1 expired (INIT)\n", __func__);
5533
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005534 SCTP_INC_STATS(net, SCTP_MIB_T1_INIT_EXPIREDS);
Frank Filz3f7a87d2005-06-20 13:14:57 -07005535
Vlad Yasevich81845c22006-01-30 15:59:54 -08005536 if (attempts <= asoc->max_init_attempts) {
Frank Filz3f7a87d2005-06-20 13:14:57 -07005537 bp = (struct sctp_bind_addr *) &asoc->base.bind_addr;
5538 repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0);
5539 if (!repl)
5540 return SCTP_DISPOSITION_NOMEM;
5541
5542 /* Choose transport for INIT. */
5543 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT,
5544 SCTP_CHUNK(repl));
5545
5546 /* Issue a sideeffect to do the needed accounting. */
5547 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART,
5548 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
5549
5550 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
5551 } else {
Daniel Borkmannbb333812013-06-28 19:49:40 +02005552 pr_debug("%s: giving up on INIT, attempts:%d "
5553 "max_init_attempts:%d\n", __func__, attempts,
5554 asoc->max_init_attempts);
5555
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005556 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5557 SCTP_ERROR(ETIMEDOUT));
Frank Filz3f7a87d2005-06-20 13:14:57 -07005558 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08005559 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Frank Filz3f7a87d2005-06-20 13:14:57 -07005560 return SCTP_DISPOSITION_DELETE_TCB;
5561 }
5562
5563 return SCTP_DISPOSITION_CONSUME;
5564}
5565
5566/*
5567 * sctp_sf_t1_cookie_timer_expire
5568 *
5569 * Section: 4 Note: 2
5570 * Verification Tag:
5571 * Inputs
5572 * (endpoint, asoc)
5573 *
5574 * RFC 2960 Section 4 Notes
5575 * 3) If the T1-cookie timer expires, the endpoint MUST retransmit
Linus Torvalds1da177e2005-04-16 15:20:36 -07005576 * COOKIE ECHO and re-start the T1-cookie timer without changing
5577 * state. This MUST be repeated up to 'Max.Init.Retransmits' times.
5578 * After that, the endpoint MUST abort the initialization process and
5579 * report the error to SCTP user.
5580 *
5581 * Outputs
5582 * (timers, events)
5583 *
5584 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005585sctp_disposition_t sctp_sf_t1_cookie_timer_expire(struct net *net,
5586 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005587 const struct sctp_association *asoc,
5588 const sctp_subtype_t type,
5589 void *arg,
5590 sctp_cmd_seq_t *commands)
5591{
Frank Filz3f7a87d2005-06-20 13:14:57 -07005592 struct sctp_chunk *repl = NULL;
5593 int attempts = asoc->init_err_counter + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005594
Daniel Borkmannbb333812013-06-28 19:49:40 +02005595 pr_debug("%s: timer T1 expired (COOKIE-ECHO)\n", __func__);
5596
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005597 SCTP_INC_STATS(net, SCTP_MIB_T1_COOKIE_EXPIREDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005598
Vlad Yasevich81845c22006-01-30 15:59:54 -08005599 if (attempts <= asoc->max_init_attempts) {
Frank Filz3f7a87d2005-06-20 13:14:57 -07005600 repl = sctp_make_cookie_echo(asoc, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005601 if (!repl)
Frank Filz3f7a87d2005-06-20 13:14:57 -07005602 return SCTP_DISPOSITION_NOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005603
Vlad Yasevich96cd0d32008-09-08 14:00:26 -04005604 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT,
5605 SCTP_CHUNK(repl));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005606 /* Issue a sideeffect to do the needed accounting. */
Frank Filz3f7a87d2005-06-20 13:14:57 -07005607 sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART,
5608 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
5609
Linus Torvalds1da177e2005-04-16 15:20:36 -07005610 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
5611 } else {
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005612 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5613 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005614 sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
Al Virodc251b22006-11-20 17:00:44 -08005615 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005616 return SCTP_DISPOSITION_DELETE_TCB;
5617 }
5618
5619 return SCTP_DISPOSITION_CONSUME;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005620}
5621
5622/* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN
5623 * with the updated last sequential TSN received from its peer.
5624 *
5625 * An endpoint should limit the number of retransmissions of the
5626 * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'.
5627 * If this threshold is exceeded the endpoint should destroy the TCB and
5628 * MUST report the peer endpoint unreachable to the upper layer (and
5629 * thus the association enters the CLOSED state). The reception of any
5630 * packet from its peer (i.e. as the peer sends all of its queued DATA
5631 * chunks) should clear the endpoint's retransmission count and restart
5632 * the T2-Shutdown timer, giving its peer ample opportunity to transmit
5633 * all of its queued DATA chunks that have not yet been sent.
5634 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005635sctp_disposition_t sctp_sf_t2_timer_expire(struct net *net,
5636 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005637 const struct sctp_association *asoc,
5638 const sctp_subtype_t type,
5639 void *arg,
5640 sctp_cmd_seq_t *commands)
5641{
5642 struct sctp_chunk *reply = NULL;
5643
Daniel Borkmannbb333812013-06-28 19:49:40 +02005644 pr_debug("%s: timer T2 expired\n", __func__);
5645
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005646 SCTP_INC_STATS(net, SCTP_MIB_T2_SHUTDOWN_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005647
Neil Horman58fbbed2008-02-29 11:40:56 -08005648 ((struct sctp_association *)asoc)->shutdown_retries++;
5649
Linus Torvalds1da177e2005-04-16 15:20:36 -07005650 if (asoc->overall_error_count >= asoc->max_retrans) {
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005651 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5652 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005653 /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
5654 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08005655 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005656 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5657 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005658 return SCTP_DISPOSITION_DELETE_TCB;
5659 }
5660
5661 switch (asoc->state) {
5662 case SCTP_STATE_SHUTDOWN_SENT:
5663 reply = sctp_make_shutdown(asoc, NULL);
5664 break;
5665
5666 case SCTP_STATE_SHUTDOWN_ACK_SENT:
5667 reply = sctp_make_shutdown_ack(asoc, NULL);
5668 break;
5669
5670 default:
5671 BUG();
5672 break;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07005673 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005674
5675 if (!reply)
5676 goto nomem;
5677
Wei Yongjun6345b192009-04-26 23:13:35 +08005678 /* Do some failure management (Section 8.2).
5679 * If we remove the transport an SHUTDOWN was last sent to, don't
5680 * do failure management.
5681 */
5682 if (asoc->shutdown_last_sent_to)
5683 sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE,
5684 SCTP_TRANSPORT(asoc->shutdown_last_sent_to));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005685
5686 /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for
5687 * the T2-shutdown timer.
5688 */
5689 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply));
5690
5691 /* Restart the T2-shutdown timer. */
5692 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
5693 SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
5694 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
5695 return SCTP_DISPOSITION_CONSUME;
5696
5697nomem:
5698 return SCTP_DISPOSITION_NOMEM;
5699}
5700
5701/*
5702 * ADDIP Section 4.1 ASCONF CHunk Procedures
5703 * If the T4 RTO timer expires the endpoint should do B1 to B5
5704 */
5705sctp_disposition_t sctp_sf_t4_timer_expire(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005706 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005707 const struct sctp_endpoint *ep,
5708 const struct sctp_association *asoc,
5709 const sctp_subtype_t type,
5710 void *arg,
5711 sctp_cmd_seq_t *commands)
5712{
5713 struct sctp_chunk *chunk = asoc->addip_last_asconf;
5714 struct sctp_transport *transport = chunk->transport;
5715
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005716 SCTP_INC_STATS(net, SCTP_MIB_T4_RTO_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005717
Linus Torvalds1da177e2005-04-16 15:20:36 -07005718 /* ADDIP 4.1 B1) Increment the error counters and perform path failure
5719 * detection on the appropriate destination address as defined in
5720 * RFC2960 [5] section 8.1 and 8.2.
5721 */
Wei Yongjun10a43ce2009-04-26 23:14:42 +08005722 if (transport)
5723 sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE,
5724 SCTP_TRANSPORT(transport));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005725
5726 /* Reconfig T4 timer and transport. */
5727 sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk));
5728
5729 /* ADDIP 4.1 B2) Increment the association error counters and perform
5730 * endpoint failure detection on the association as defined in
5731 * RFC2960 [5] section 8.1 and 8.2.
5732 * association error counter is incremented in SCTP_CMD_STRIKE.
5733 */
5734 if (asoc->overall_error_count >= asoc->max_retrans) {
5735 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
5736 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005737 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5738 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005739 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08005740 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005741 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5742 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005743 return SCTP_DISPOSITION_ABORT;
5744 }
5745
5746 /* ADDIP 4.1 B3) Back-off the destination address RTO value to which
5747 * the ASCONF chunk was sent by doubling the RTO timer value.
5748 * This is done in SCTP_CMD_STRIKE.
5749 */
5750
5751 /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible
5752 * choose an alternate destination address (please refer to RFC2960
5753 * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09005754 * chunk, it MUST be the same (including its serial number) as the last
Linus Torvalds1da177e2005-04-16 15:20:36 -07005755 * ASCONF sent.
5756 */
5757 sctp_chunk_hold(asoc->addip_last_asconf);
5758 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
5759 SCTP_CHUNK(asoc->addip_last_asconf));
5760
5761 /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different
5762 * destination is selected, then the RTO used will be that of the new
5763 * destination address.
5764 */
5765 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
5766 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
5767
5768 return SCTP_DISPOSITION_CONSUME;
5769}
5770
5771/* sctpimpguide-05 Section 2.12.2
5772 * The sender of the SHUTDOWN MAY also start an overall guard timer
5773 * 'T5-shutdown-guard' to bound the overall time for shutdown sequence.
5774 * At the expiration of this timer the sender SHOULD abort the association
5775 * by sending an ABORT chunk.
5776 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005777sctp_disposition_t sctp_sf_t5_timer_expire(struct net *net,
5778 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005779 const struct sctp_association *asoc,
5780 const sctp_subtype_t type,
5781 void *arg,
5782 sctp_cmd_seq_t *commands)
5783{
5784 struct sctp_chunk *reply = NULL;
5785
Daniel Borkmannbb333812013-06-28 19:49:40 +02005786 pr_debug("%s: timer T5 expired\n", __func__);
5787
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005788 SCTP_INC_STATS(net, SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005789
5790 reply = sctp_make_abort(asoc, NULL, 0);
5791 if (!reply)
5792 goto nomem;
5793
5794 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07005795 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
5796 SCTP_ERROR(ETIMEDOUT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005797 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08005798 SCTP_PERR(SCTP_ERROR_NO_ERROR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005799
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005800 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
5801 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Vlad Yasevicha1080a82008-10-09 14:33:26 -07005802
Linus Torvalds1da177e2005-04-16 15:20:36 -07005803 return SCTP_DISPOSITION_DELETE_TCB;
5804nomem:
5805 return SCTP_DISPOSITION_NOMEM;
5806}
5807
5808/* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires,
5809 * the association is automatically closed by starting the shutdown process.
5810 * The work that needs to be done is same as when SHUTDOWN is initiated by
5811 * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown().
5812 */
5813sctp_disposition_t sctp_sf_autoclose_timer_expire(
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005814 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005815 const struct sctp_endpoint *ep,
5816 const struct sctp_association *asoc,
5817 const sctp_subtype_t type,
5818 void *arg,
5819 sctp_cmd_seq_t *commands)
5820{
5821 int disposition;
5822
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00005823 SCTP_INC_STATS(net, SCTP_MIB_AUTOCLOSE_EXPIREDS);
Sridhar Samudralaac0b0462006-08-22 00:15:33 -07005824
Linus Torvalds1da177e2005-04-16 15:20:36 -07005825 /* From 9.2 Shutdown of an Association
5826 * Upon receipt of the SHUTDOWN primitive from its upper
5827 * layer, the endpoint enters SHUTDOWN-PENDING state and
5828 * remains there until all outstanding data has been
5829 * acknowledged by its peer. The endpoint accepts no new data
5830 * from its upper layer, but retransmits data to the far end
5831 * if necessary to fill gaps.
5832 */
5833 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
5834 SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING));
5835
Linus Torvalds1da177e2005-04-16 15:20:36 -07005836 disposition = SCTP_DISPOSITION_CONSUME;
5837 if (sctp_outq_is_empty(&asoc->outqueue)) {
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005838 disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005839 arg, commands);
5840 }
5841 return disposition;
5842}
5843
5844/*****************************************************************************
5845 * These are sa state functions which could apply to all types of events.
5846 ****************************************************************************/
5847
5848/*
5849 * This table entry is not implemented.
5850 *
5851 * Inputs
5852 * (endpoint, asoc, chunk)
5853 *
5854 * The return value is the disposition of the chunk.
5855 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005856sctp_disposition_t sctp_sf_not_impl(struct net *net,
5857 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005858 const struct sctp_association *asoc,
5859 const sctp_subtype_t type,
5860 void *arg,
5861 sctp_cmd_seq_t *commands)
5862{
5863 return SCTP_DISPOSITION_NOT_IMPL;
5864}
5865
5866/*
5867 * This table entry represents a bug.
5868 *
5869 * Inputs
5870 * (endpoint, asoc, chunk)
5871 *
5872 * The return value is the disposition of the chunk.
5873 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005874sctp_disposition_t sctp_sf_bug(struct net *net,
5875 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005876 const struct sctp_association *asoc,
5877 const sctp_subtype_t type,
5878 void *arg,
5879 sctp_cmd_seq_t *commands)
5880{
5881 return SCTP_DISPOSITION_BUG;
5882}
5883
5884/*
5885 * This table entry represents the firing of a timer in the wrong state.
5886 * Since timer deletion cannot be guaranteed a timer 'may' end up firing
5887 * when the association is in the wrong state. This event should
5888 * be ignored, so as to prevent any rearming of the timer.
5889 *
5890 * Inputs
5891 * (endpoint, asoc, chunk)
5892 *
5893 * The return value is the disposition of the chunk.
5894 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005895sctp_disposition_t sctp_sf_timer_ignore(struct net *net,
5896 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005897 const struct sctp_association *asoc,
5898 const sctp_subtype_t type,
5899 void *arg,
5900 sctp_cmd_seq_t *commands)
5901{
Daniel Borkmannbb333812013-06-28 19:49:40 +02005902 pr_debug("%s: timer %d ignored\n", __func__, type.chunk);
5903
Linus Torvalds1da177e2005-04-16 15:20:36 -07005904 return SCTP_DISPOSITION_CONSUME;
5905}
5906
5907/********************************************************************
5908 * 2nd Level Abstractions
5909 ********************************************************************/
5910
5911/* Pull the SACK chunk based on the SACK header. */
5912static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk)
5913{
5914 struct sctp_sackhdr *sack;
5915 unsigned int len;
5916 __u16 num_blocks;
5917 __u16 num_dup_tsns;
5918
5919 /* Protect ourselves from reading too far into
5920 * the skb from a bogus sender.
5921 */
5922 sack = (struct sctp_sackhdr *) chunk->skb->data;
5923
5924 num_blocks = ntohs(sack->num_gap_ack_blocks);
5925 num_dup_tsns = ntohs(sack->num_dup_tsns);
5926 len = sizeof(struct sctp_sackhdr);
5927 len += (num_blocks + num_dup_tsns) * sizeof(__u32);
5928 if (len > chunk->skb->len)
5929 return NULL;
5930
5931 skb_pull(chunk->skb, len);
5932
5933 return sack;
5934}
5935
5936/* Create an ABORT packet to be sent as a response, with the specified
5937 * error causes.
5938 */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00005939static struct sctp_packet *sctp_abort_pkt_new(struct net *net,
5940 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005941 const struct sctp_association *asoc,
5942 struct sctp_chunk *chunk,
5943 const void *payload,
5944 size_t paylen)
5945{
5946 struct sctp_packet *packet;
5947 struct sctp_chunk *abort;
5948
Eric W. Biederman2ce95502012-08-06 08:43:06 +00005949 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005950
5951 if (packet) {
5952 /* Make an ABORT.
5953 * The T bit will be set if the asoc is NULL.
5954 */
5955 abort = sctp_make_abort(asoc, chunk, paylen);
5956 if (!abort) {
5957 sctp_ootb_pkt_free(packet);
5958 return NULL;
5959 }
Jerome Forissier047a2422005-04-28 11:58:43 -07005960
5961 /* Reflect vtag if T-Bit is set */
5962 if (sctp_test_T_bit(abort))
5963 packet->vtag = ntohl(chunk->sctp_hdr->vtag);
5964
Linus Torvalds1da177e2005-04-16 15:20:36 -07005965 /* Add specified error causes, i.e., payload, to the
5966 * end of the chunk.
5967 */
5968 sctp_addto_chunk(abort, paylen, payload);
5969
5970 /* Set the skb to the belonging sock for accounting. */
5971 abort->skb->sk = ep->base.sk;
5972
5973 sctp_packet_append_chunk(packet, abort);
5974
5975 }
5976
5977 return packet;
5978}
5979
5980/* Allocate a packet for responding in the OOTB conditions. */
Eric W. Biederman2ce95502012-08-06 08:43:06 +00005981static struct sctp_packet *sctp_ootb_pkt_new(struct net *net,
5982 const struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005983 const struct sctp_chunk *chunk)
5984{
5985 struct sctp_packet *packet;
5986 struct sctp_transport *transport;
5987 __u16 sport;
5988 __u16 dport;
5989 __u32 vtag;
5990
5991 /* Get the source and destination port from the inbound packet. */
5992 sport = ntohs(chunk->sctp_hdr->dest);
5993 dport = ntohs(chunk->sctp_hdr->source);
5994
5995 /* The V-tag is going to be the same as the inbound packet if no
5996 * association exists, otherwise, use the peer's vtag.
5997 */
5998 if (asoc) {
Wei Yongjun02c4e122007-08-31 10:03:58 +08005999 /* Special case the INIT-ACK as there is no peer's vtag
6000 * yet.
6001 */
wangweidongcb3f8372013-12-23 12:16:50 +08006002 switch (chunk->chunk_hdr->type) {
Wei Yongjun02c4e122007-08-31 10:03:58 +08006003 case SCTP_CID_INIT_ACK:
6004 {
6005 sctp_initack_chunk_t *initack;
6006
6007 initack = (sctp_initack_chunk_t *)chunk->chunk_hdr;
6008 vtag = ntohl(initack->init_hdr.init_tag);
6009 break;
6010 }
6011 default:
6012 vtag = asoc->peer.i.init_tag;
6013 break;
6014 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07006015 } else {
6016 /* Special case the INIT and stale COOKIE_ECHO as there is no
6017 * vtag yet.
6018 */
wangweidongcb3f8372013-12-23 12:16:50 +08006019 switch (chunk->chunk_hdr->type) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07006020 case SCTP_CID_INIT:
6021 {
6022 sctp_init_chunk_t *init;
6023
6024 init = (sctp_init_chunk_t *)chunk->chunk_hdr;
6025 vtag = ntohl(init->init_hdr.init_tag);
6026 break;
6027 }
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09006028 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -07006029 vtag = ntohl(chunk->sctp_hdr->vtag);
6030 break;
6031 }
6032 }
6033
6034 /* Make a transport for the bucket, Eliza... */
Eric W. Biederman89bf3452012-08-07 07:26:14 +00006035 transport = sctp_transport_new(net, sctp_source(chunk), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006036 if (!transport)
6037 goto nomem;
6038
6039 /* Cache a route for the transport with the chunk's destination as
6040 * the source address.
6041 */
Al Viro16b0a032006-11-20 17:13:38 -08006042 sctp_transport_route(transport, (union sctp_addr *)&chunk->dest,
Eric W. Biederman2ce95502012-08-06 08:43:06 +00006043 sctp_sk(net->sctp.ctl_sock));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006044
6045 packet = sctp_packet_init(&transport->packet, transport, sport, dport);
6046 packet = sctp_packet_config(packet, vtag, 0);
6047
6048 return packet;
6049
6050nomem:
6051 return NULL;
6052}
6053
6054/* Free the packet allocated earlier for responding in the OOTB condition. */
6055void sctp_ootb_pkt_free(struct sctp_packet *packet)
6056{
6057 sctp_transport_free(packet->transport);
6058}
6059
6060/* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00006061static void sctp_send_stale_cookie_err(struct net *net,
6062 const struct sctp_endpoint *ep,
Linus Torvalds1da177e2005-04-16 15:20:36 -07006063 const struct sctp_association *asoc,
6064 const struct sctp_chunk *chunk,
6065 sctp_cmd_seq_t *commands,
6066 struct sctp_chunk *err_chunk)
6067{
6068 struct sctp_packet *packet;
6069
6070 if (err_chunk) {
Eric W. Biederman2ce95502012-08-06 08:43:06 +00006071 packet = sctp_ootb_pkt_new(net, asoc, chunk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006072 if (packet) {
6073 struct sctp_signed_cookie *cookie;
6074
6075 /* Override the OOTB vtag from the cookie. */
6076 cookie = chunk->subh.cookie_hdr;
6077 packet->vtag = cookie->c.peer_vtag;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09006078
Linus Torvalds1da177e2005-04-16 15:20:36 -07006079 /* Set the skb to the belonging sock for accounting. */
6080 err_chunk->skb->sk = ep->base.sk;
6081 sctp_packet_append_chunk(packet, err_chunk);
6082 sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT,
6083 SCTP_PACKET(packet));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006084 SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006085 } else
6086 sctp_chunk_free (err_chunk);
6087 }
6088}
6089
6090
6091/* Process a data chunk */
6092static int sctp_eat_data(const struct sctp_association *asoc,
6093 struct sctp_chunk *chunk,
6094 sctp_cmd_seq_t *commands)
6095{
6096 sctp_datahdr_t *data_hdr;
6097 struct sctp_chunk *err;
6098 size_t datalen;
6099 sctp_verb_t deliver;
6100 int tmp;
6101 __u32 tsn;
Neil Horman7c3ceb4f2006-05-05 17:02:09 -07006102 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
Neil Horman049b3ff2005-11-11 16:08:24 -08006103 struct sock *sk = asoc->base.sk;
Eric W. Biederman24cb81a2012-08-07 07:28:09 +00006104 struct net *net = sock_net(sk);
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006105 u16 ssn;
6106 u16 sid;
6107 u8 ordered = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07006108
6109 data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data;
6110 skb_pull(chunk->skb, sizeof(sctp_datahdr_t));
6111
6112 tsn = ntohl(data_hdr->tsn);
Daniel Borkmannbb333812013-06-28 19:49:40 +02006113 pr_debug("%s: TSN 0x%x\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006114
6115 /* ASSERT: Now skb->data is really the user data. */
6116
Linus Torvalds1da177e2005-04-16 15:20:36 -07006117 /* Process ECN based congestion.
6118 *
6119 * Since the chunk structure is reused for all chunks within
6120 * a packet, we use ecn_ce_done to track if we've already
6121 * done CE processing for this packet.
6122 *
6123 * We need to do ECN processing even if we plan to discard the
6124 * chunk later.
6125 */
6126
6127 if (!chunk->ecn_ce_done) {
6128 struct sctp_af *af;
6129 chunk->ecn_ce_done = 1;
6130
6131 af = sctp_get_af_specific(
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07006132 ipver2af(ip_hdr(chunk->skb)->version));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006133
6134 if (af && af->is_ce(chunk->skb) && asoc->peer.ecn_capable) {
6135 /* Do real work as sideffect. */
6136 sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE,
6137 SCTP_U32(tsn));
6138 }
6139 }
6140
6141 tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn);
6142 if (tmp < 0) {
6143 /* The TSN is too high--silently discard the chunk and
6144 * count on it getting retransmitted later.
6145 */
Michele Baldessari196d6752012-12-01 04:49:42 +00006146 if (chunk->asoc)
6147 chunk->asoc->stats.outofseqtsns++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07006148 return SCTP_IERROR_HIGH_TSN;
6149 } else if (tmp > 0) {
6150 /* This is a duplicate. Record it. */
6151 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn));
6152 return SCTP_IERROR_DUP_TSN;
6153 }
6154
6155 /* This is a new TSN. */
6156
6157 /* Discard if there is no room in the receive window.
6158 * Actually, allow a little bit of overflow (up to a MTU).
6159 */
6160 datalen = ntohs(chunk->chunk_hdr->length);
6161 datalen -= sizeof(sctp_data_chunk_t);
6162
6163 deliver = SCTP_CMD_CHUNK_ULP;
6164
6165 /* Think about partial delivery. */
6166 if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) {
6167
6168 /* Even if we don't accept this chunk there is
6169 * memory pressure.
6170 */
6171 sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL());
6172 }
6173
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09006174 /* Spill over rwnd a little bit. Note: While allowed, this spill over
Linus Torvalds1da177e2005-04-16 15:20:36 -07006175 * seems a bit troublesome in that frag_point varies based on
6176 * PMTU. In cases, such as loopback, this might be a rather
6177 * large spill over.
6178 */
Daniel Borkmann362d5202014-04-14 21:45:17 +02006179 if ((!chunk->data_accepted) && (!asoc->rwnd || asoc->rwnd_over ||
Neil Horman4d93df02007-08-15 16:07:44 -07006180 (datalen > asoc->rwnd + asoc->frag_point))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07006181
6182 /* If this is the next TSN, consider reneging to make
6183 * room. Note: Playing nice with a confused sender. A
6184 * malicious sender can still eat up all our buffer
6185 * space and in the future we may want to detect and
6186 * do more drastic reneging.
6187 */
Neil Horman7c3ceb4f2006-05-05 17:02:09 -07006188 if (sctp_tsnmap_has_gap(map) &&
6189 (sctp_tsnmap_get_ctsn(map) + 1) == tsn) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02006190 pr_debug("%s: reneging for tsn:%u\n", __func__, tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006191 deliver = SCTP_CMD_RENEGE;
6192 } else {
Daniel Borkmannbb333812013-06-28 19:49:40 +02006193 pr_debug("%s: discard tsn:%u len:%zu, rwnd:%d\n",
6194 __func__, tsn, datalen, asoc->rwnd);
6195
Linus Torvalds1da177e2005-04-16 15:20:36 -07006196 return SCTP_IERROR_IGNORE_TSN;
6197 }
6198 }
6199
6200 /*
Neil Horman4d93df02007-08-15 16:07:44 -07006201 * Also try to renege to limit our memory usage in the event that
6202 * we are under memory pressure
Hideo Aoki3ab224b2007-12-31 00:11:19 -08006203 * If we can't renege, don't worry about it, the sk_rmem_schedule
Neil Horman4d93df02007-08-15 16:07:44 -07006204 * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our
6205 * memory usage too much
6206 */
6207 if (*sk->sk_prot_creator->memory_pressure) {
6208 if (sctp_tsnmap_has_gap(map) &&
wangweidongf7010e62013-12-23 12:16:52 +08006209 (sctp_tsnmap_get_ctsn(map) + 1) == tsn) {
Daniel Borkmannbb333812013-06-28 19:49:40 +02006210 pr_debug("%s: under pressure, reneging for tsn:%u\n",
6211 __func__, tsn);
Neil Horman4d93df02007-08-15 16:07:44 -07006212 deliver = SCTP_CMD_RENEGE;
6213 }
6214 }
6215
6216 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07006217 * Section 3.3.10.9 No User Data (9)
6218 *
6219 * Cause of error
6220 * ---------------
6221 * No User Data: This error cause is returned to the originator of a
6222 * DATA chunk if a received DATA chunk has no user data.
6223 */
6224 if (unlikely(0 == datalen)) {
6225 err = sctp_make_abort_no_data(asoc, chunk, tsn);
6226 if (err) {
6227 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
6228 SCTP_CHUNK(err));
6229 }
6230 /* We are going to ABORT, so we might as well stop
6231 * processing the rest of the chunks in the packet.
6232 */
wangweidongcb3f8372013-12-23 12:16:50 +08006233 sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL());
Sridhar Samudrala8de8c872006-05-19 10:58:12 -07006234 sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
6235 SCTP_ERROR(ECONNABORTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006236 sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
Al Viro5be291f2006-11-20 17:01:06 -08006237 SCTP_PERR(SCTP_ERROR_NO_DATA));
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006238 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
6239 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006240 return SCTP_IERROR_NO_DATA;
6241 }
6242
Sridhar Samudrala9faa7302006-07-21 14:49:07 -07006243 chunk->data_accepted = 1;
6244
Linus Torvalds1da177e2005-04-16 15:20:36 -07006245 /* Note: Some chunks may get overcounted (if we drop) or overcounted
6246 * if we renege and the chunk arrives again.
6247 */
Michele Baldessari196d6752012-12-01 04:49:42 +00006248 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006249 SCTP_INC_STATS(net, SCTP_MIB_INUNORDERCHUNKS);
Michele Baldessari196d6752012-12-01 04:49:42 +00006250 if (chunk->asoc)
6251 chunk->asoc->stats.iuodchunks++;
6252 } else {
Eric W. Biedermanb01a2402012-08-06 08:47:55 +00006253 SCTP_INC_STATS(net, SCTP_MIB_INORDERCHUNKS);
Michele Baldessari196d6752012-12-01 04:49:42 +00006254 if (chunk->asoc)
6255 chunk->asoc->stats.iodchunks++;
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006256 ordered = 1;
6257 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07006258
6259 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
6260 *
6261 * If an endpoint receive a DATA chunk with an invalid stream
6262 * identifier, it shall acknowledge the reception of the DATA chunk
6263 * following the normal procedure, immediately send an ERROR chunk
6264 * with cause set to "Invalid Stream Identifier" (See Section 3.3.10)
6265 * and discard the DATA chunk.
6266 */
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006267 sid = ntohs(data_hdr->stream);
6268 if (sid >= asoc->c.sinit_max_instreams) {
Vlad Yasevich3888e9e2008-07-08 02:28:39 -07006269 /* Mark tsn as received even though we drop it */
6270 sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn));
6271
Linus Torvalds1da177e2005-04-16 15:20:36 -07006272 err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM,
6273 &data_hdr->stream,
Vlad Yasevich6383cfb2009-11-23 15:53:56 -05006274 sizeof(data_hdr->stream),
6275 sizeof(u16));
Linus Torvalds1da177e2005-04-16 15:20:36 -07006276 if (err)
6277 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
6278 SCTP_CHUNK(err));
6279 return SCTP_IERROR_BAD_STREAM;
6280 }
6281
Vlad Yasevichf1751c52009-09-04 18:21:03 -04006282 /* Check to see if the SSN is possible for this TSN.
6283 * The biggest gap we can record is 4K wide. Since SSNs wrap
6284 * at an unsigned short, there is no way that an SSN can
6285 * wrap and for a valid TSN. We can simply check if the current
6286 * SSN is smaller then the next expected one. If it is, it wrapped
6287 * and is invalid.
6288 */
6289 ssn = ntohs(data_hdr->ssn);
6290 if (ordered && SSN_lt(ssn, sctp_ssn_peek(&asoc->ssnmap->in, sid))) {
6291 return SCTP_IERROR_PROTO_VIOLATION;
6292 }
6293
Linus Torvalds1da177e2005-04-16 15:20:36 -07006294 /* Send the data up to the user. Note: Schedule the
6295 * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK
6296 * chunk needs the updated rwnd.
6297 */
6298 sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk));
6299
6300 return SCTP_IERROR_NO_ERROR;
6301}