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Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001/*
2 * net/dccp/options.c
3 *
4 * An implementation of the DCCP protocol
Ian McDonald1bc09862005-08-20 00:23:43 -03005 * Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
6 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Ian McDonalde6bccd32006-08-26 19:01:30 -07007 * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz>
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07008 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070014#include <linux/dccp.h>
15#include <linux/module.h>
16#include <linux/types.h>
Gerrit Renker76fd1e82007-10-24 10:46:58 -020017#include <asm/unaligned.h>
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070018#include <linux/kernel.h>
19#include <linux/skbuff.h>
20
Arnaldo Carvalho de Meloae31c332005-09-18 00:17:51 -070021#include "ackvec.h"
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070022#include "ccid.h"
23#include "dccp.h"
Andrea Bittauafe00252006-03-20 17:43:56 -080024#include "feat.h"
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070025
Gerrit Renkerafb0a34d2006-11-13 13:25:41 -020026int sysctl_dccp_feat_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW;
27int sysctl_dccp_feat_rx_ccid = DCCPF_INITIAL_CCID;
28int sysctl_dccp_feat_tx_ccid = DCCPF_INITIAL_CCID;
29int sysctl_dccp_feat_ack_ratio = DCCPF_INITIAL_ACK_RATIO;
30int sysctl_dccp_feat_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR;
31int sysctl_dccp_feat_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070032
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070033static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
34{
35 u32 value = 0;
36
37 if (len > 3)
38 value += *bf++ << 24;
39 if (len > 2)
40 value += *bf++ << 16;
41 if (len > 1)
42 value += *bf++ << 8;
43 if (len > 0)
44 value += *bf;
45
46 return value;
47}
48
Gerrit Renker8b819412007-12-13 12:29:24 -020049/**
50 * dccp_parse_options - Parse DCCP options present in @skb
51 * @sk: client|server|listening dccp socket (when @dreq != NULL)
52 * @dreq: request socket to use during connection setup, or NULL
53 */
54int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
55 struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070056{
57 struct dccp_sock *dp = dccp_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070058 const struct dccp_hdr *dh = dccp_hdr(skb);
59 const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
Andrea Bittaubdf13d22006-11-24 13:02:42 -020060 u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070061 unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
62 unsigned char *opt_ptr = options;
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -030063 const unsigned char *opt_end = (unsigned char *)dh +
64 (dh->dccph_doff * 4);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070065 struct dccp_options_received *opt_recv = &dp->dccps_options_received;
66 unsigned char opt, len;
67 unsigned char *value;
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -030068 u32 elapsed_time;
Gerrit Renker76fd1e82007-10-24 10:46:58 -020069 __be32 opt_val;
Andrea Bittauafe00252006-03-20 17:43:56 -080070 int rc;
71 int mandatory = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070072
73 memset(opt_recv, 0, sizeof(*opt_recv));
74
David S. Millerfb950492006-03-20 22:36:01 -080075 opt = len = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070076 while (opt_ptr != opt_end) {
77 opt = *opt_ptr++;
78 len = 0;
79 value = NULL;
80
81 /* Check if this isn't a single byte option */
82 if (opt > DCCPO_MAX_RESERVED) {
83 if (opt_ptr == opt_end)
84 goto out_invalid_option;
85
86 len = *opt_ptr++;
87 if (len < 3)
88 goto out_invalid_option;
89 /*
90 * Remove the type and len fields, leaving
91 * just the value size
92 */
93 len -= 2;
94 value = opt_ptr;
95 opt_ptr += len;
96
97 if (opt_ptr > opt_end)
98 goto out_invalid_option;
99 }
100
Gerrit Renker8b819412007-12-13 12:29:24 -0200101 /*
102 * CCID-Specific Options (from RFC 4340, sec. 10.3):
103 *
104 * Option numbers 128 through 191 are for options sent from the
105 * HC-Sender to the HC-Receiver; option numbers 192 through 255
106 * are for options sent from the HC-Receiver to the HC-Sender.
107 *
108 * CCID-specific options are ignored during connection setup, as
109 * negotiation may still be in progress (see RFC 4340, 10.3).
110 *
111 */
112 if (dreq != NULL && opt >= 128)
113 goto ignore_option;
114
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700115 switch (opt) {
116 case DCCPO_PADDING:
117 break;
Andrea Bittauafe00252006-03-20 17:43:56 -0800118 case DCCPO_MANDATORY:
119 if (mandatory)
120 goto out_invalid_option;
Arnaldo Carvalho de Melo6df94242006-03-20 22:06:02 -0800121 if (pkt_type != DCCP_PKT_DATA)
122 mandatory = 1;
Andrea Bittauafe00252006-03-20 17:43:56 -0800123 break;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700124 case DCCPO_NDP_COUNT:
125 if (len > 3)
126 goto out_invalid_option;
127
128 opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
Gerrit Renker09dbc382006-11-14 12:57:34 -0200129 dccp_pr_debug("%s rx opt: NDP count=%d\n", dccp_role(sk),
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300130 opt_recv->dccpor_ndp);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700131 break;
Andrea Bittauafe00252006-03-20 17:43:56 -0800132 case DCCPO_CHANGE_L:
133 /* fall through */
134 case DCCPO_CHANGE_R:
Gerrit Renkercf863142007-12-13 12:48:19 -0200135 if (pkt_type == DCCP_PKT_DATA)
136 break;
Andrea Bittauafe00252006-03-20 17:43:56 -0800137 if (len < 2)
138 goto out_invalid_option;
139 rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
140 len - 1);
141 /*
142 * When there is a change error, change_recv is
143 * responsible for dealing with it. i.e. reply with an
144 * empty confirm.
145 * If the change was mandatory, then we need to die.
146 */
147 if (rc && mandatory)
148 goto out_invalid_option;
149 break;
150 case DCCPO_CONFIRM_L:
151 /* fall through */
152 case DCCPO_CONFIRM_R:
Gerrit Renkercf863142007-12-13 12:48:19 -0200153 if (pkt_type == DCCP_PKT_DATA)
154 break;
155 if (len < 2) /* FIXME this disallows empty confirm */
Andrea Bittauafe00252006-03-20 17:43:56 -0800156 goto out_invalid_option;
157 if (dccp_feat_confirm_recv(sk, opt, *value,
158 value + 1, len - 1))
159 goto out_invalid_option;
160 break;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700161 case DCCPO_ACK_VECTOR_0:
Arnaldo Carvalho de Meloae31c332005-09-18 00:17:51 -0700162 case DCCPO_ACK_VECTOR_1:
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200163 if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
Arnaldo Carvalho de Meloe5a6de92006-03-20 22:30:51 -0800164 break;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700165
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800166 if (dccp_msk(sk)->dccpms_send_ack_vector &&
Andrea Bittaubdf13d22006-11-24 13:02:42 -0200167 dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
Arnaldo Carvalho de Meloae31c332005-09-18 00:17:51 -0700168 goto out_invalid_option;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700169 break;
170 case DCCPO_TIMESTAMP:
171 if (len != 4)
172 goto out_invalid_option;
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200173 /*
174 * RFC 4340 13.1: "The precise time corresponding to
175 * Timestamp Value zero is not specified". We use
176 * zero to indicate absence of a meaningful timestamp.
177 */
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200178 opt_val = get_unaligned((__be32 *)value);
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200179 if (unlikely(opt_val == 0)) {
180 DCCP_WARN("Timestamp with zero value\n");
181 break;
182 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700183
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200184 if (dreq != NULL) {
185 dreq->dreq_timestamp_echo = ntohl(opt_val);
186 dreq->dreq_timestamp_time = dccp_timestamp();
187 } else {
188 opt_recv->dccpor_timestamp =
189 dp->dccps_timestamp_echo = ntohl(opt_val);
190 dp->dccps_timestamp_time = dccp_timestamp();
191 }
Gerrit Renker09dbc382006-11-14 12:57:34 -0200192 dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200193 dccp_role(sk), ntohl(opt_val),
David S. Millerf6ccf552005-08-09 20:27:14 -0700194 (unsigned long long)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700195 DCCP_SKB_CB(skb)->dccpd_ack_seq);
196 break;
197 case DCCPO_TIMESTAMP_ECHO:
Ian McDonald1bc09862005-08-20 00:23:43 -0300198 if (len != 4 && len != 6 && len != 8)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700199 goto out_invalid_option;
200
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200201 opt_val = get_unaligned((__be32 *)value);
202 opt_recv->dccpor_timestamp_echo = ntohl(opt_val);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700203
Gerrit Renker09dbc382006-11-14 12:57:34 -0200204 dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700205 "ackno=%llu", dccp_role(sk),
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300206 opt_recv->dccpor_timestamp_echo,
David S. Millerf6ccf552005-08-09 20:27:14 -0700207 len + 2,
208 (unsigned long long)
Ian McDonald1bc09862005-08-20 00:23:43 -0300209 DCCP_SKB_CB(skb)->dccpd_ack_seq);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700210
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200211 value += 4;
Ian McDonald1bc09862005-08-20 00:23:43 -0300212
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200213 if (len == 4) { /* no elapsed time included */
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700214 dccp_pr_debug_cat("\n");
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300215 break;
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700216 }
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300217
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200218 if (len == 6) { /* 2-byte elapsed time */
219 __be16 opt_val2 = get_unaligned((__be16 *)value);
220 elapsed_time = ntohs(opt_val2);
221 } else { /* 4-byte elapsed time */
222 opt_val = get_unaligned((__be32 *)value);
223 elapsed_time = ntohl(opt_val);
224 }
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300225
Gerrit Renkerdcad8562007-10-04 14:44:01 -0700226 dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time);
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700227
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300228 /* Give precedence to the biggest ELAPSED_TIME */
229 if (elapsed_time > opt_recv->dccpor_elapsed_time)
230 opt_recv->dccpor_elapsed_time = elapsed_time;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700231 break;
232 case DCCPO_ELAPSED_TIME:
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200233 if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */
234 break;
Ian McDonald1bc09862005-08-20 00:23:43 -0300235
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200236 if (len == 2) {
237 __be16 opt_val2 = get_unaligned((__be16 *)value);
238 elapsed_time = ntohs(opt_val2);
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200239 } else if (len == 4) {
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200240 opt_val = get_unaligned((__be32 *)value);
241 elapsed_time = ntohl(opt_val);
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200242 } else {
243 goto out_invalid_option;
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200244 }
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300245
246 if (elapsed_time > opt_recv->dccpor_elapsed_time)
247 opt_recv->dccpor_elapsed_time = elapsed_time;
Ian McDonald1bc09862005-08-20 00:23:43 -0300248
Gerrit Renker09dbc382006-11-14 12:57:34 -0200249 dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
250 dccp_role(sk), elapsed_time);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700251 break;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700252 case 128 ... 191: {
253 const u16 idx = value - options;
254
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300255 if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
256 opt, len, idx,
257 value) != 0)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700258 goto out_invalid_option;
259 }
260 break;
261 case 192 ... 255: {
262 const u16 idx = value - options;
263
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300264 if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
265 opt, len, idx,
266 value) != 0)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700267 goto out_invalid_option;
268 }
269 break;
270 default:
Gerrit Renker59348b12006-11-20 18:39:23 -0200271 DCCP_CRIT("DCCP(%p): option %d(len=%d) not "
272 "implemented, ignoring", sk, opt, len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700273 break;
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900274 }
Gerrit Renker8b819412007-12-13 12:29:24 -0200275ignore_option:
Andrea Bittauafe00252006-03-20 17:43:56 -0800276 if (opt != DCCPO_MANDATORY)
277 mandatory = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700278 }
279
Arnaldo Carvalho de Melo6df94242006-03-20 22:06:02 -0800280 /* mandatory was the last byte in option list -> reset connection */
281 if (mandatory)
282 goto out_invalid_option;
283
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700284 return 0;
285
286out_invalid_option:
287 DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
288 DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
Gerrit Renker59348b12006-11-20 18:39:23 -0200289 DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700290 return -1;
291}
292
Arnaldo Carvalho de Melob61fafc2006-03-20 21:25:11 -0800293EXPORT_SYMBOL_GPL(dccp_parse_options);
294
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700295static void dccp_encode_value_var(const u32 value, unsigned char *to,
296 const unsigned int len)
297{
298 if (len > 3)
299 *to++ = (value & 0xFF000000) >> 24;
300 if (len > 2)
301 *to++ = (value & 0xFF0000) >> 16;
302 if (len > 1)
303 *to++ = (value & 0xFF00) >> 8;
304 if (len > 0)
305 *to++ = (value & 0xFF);
306}
307
308static inline int dccp_ndp_len(const int ndp)
309{
310 return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
311}
312
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800313int dccp_insert_option(struct sock *sk, struct sk_buff *skb,
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700314 const unsigned char option,
315 const void *value, const unsigned char len)
316{
317 unsigned char *to;
318
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800319 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN)
320 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700321
322 DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;
323
324 to = skb_push(skb, len + 2);
325 *to++ = option;
326 *to++ = len + 2;
327
328 memcpy(to, value, len);
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800329 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700330}
331
332EXPORT_SYMBOL_GPL(dccp_insert_option);
333
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800334static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700335{
336 struct dccp_sock *dp = dccp_sk(sk);
337 int ndp = dp->dccps_ndp_count;
338
339 if (dccp_non_data_packet(skb))
340 ++dp->dccps_ndp_count;
341 else
342 dp->dccps_ndp_count = 0;
343
344 if (ndp > 0) {
345 unsigned char *ptr;
346 const int ndp_len = dccp_ndp_len(ndp);
347 const int len = ndp_len + 2;
348
349 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800350 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700351
352 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
353
354 ptr = skb_push(skb, len);
355 *ptr++ = DCCPO_NDP_COUNT;
356 *ptr++ = len;
357 dccp_encode_value_var(ndp, ptr, ndp_len);
358 }
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800359
360 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700361}
362
363static inline int dccp_elapsed_time_len(const u32 elapsed_time)
364{
Ian McDonaldb1c9fe72005-08-18 20:45:29 -0300365 return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700366}
367
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800368int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb,
369 u32 elapsed_time)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700370{
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700371 const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
372 const int len = 2 + elapsed_time_len;
373 unsigned char *to;
374
Ian McDonald1bc09862005-08-20 00:23:43 -0300375 if (elapsed_time_len == 0)
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800376 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700377
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800378 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
379 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700380
381 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
382
383 to = skb_push(skb, len);
384 *to++ = DCCPO_ELAPSED_TIME;
385 *to++ = len;
386
Ian McDonald1bc09862005-08-20 00:23:43 -0300387 if (elapsed_time_len == 2) {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800388 const __be16 var16 = htons((u16)elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300389 memcpy(to, &var16, 2);
390 } else {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800391 const __be32 var32 = htonl(elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300392 memcpy(to, &var32, 4);
393 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700394
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800395 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700396}
397
Arnaldo Carvalho de Melod4b81ff2005-08-23 21:51:36 -0700398EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700399
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800400int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700401{
Gerrit Renker4c70f382007-09-25 22:40:13 -0700402 __be32 now = htonl(dccp_timestamp());
Ian McDonald1bc09862005-08-20 00:23:43 -0300403 /* yes this will overflow but that is the point as we want a
404 * 10 usec 32 bit timer which mean it wraps every 11.9 hours */
405
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800406 return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700407}
408
Arnaldo Carvalho de Melod4b81ff2005-08-23 21:51:36 -0700409EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
410
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200411static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
412 struct dccp_request_sock *dreq,
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800413 struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700414{
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800415 __be32 tstamp_echo;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700416 unsigned char *to;
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200417 u32 elapsed_time, elapsed_time_len, len;
418
419 if (dreq != NULL) {
420 elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
421 tstamp_echo = htonl(dreq->dreq_timestamp_echo);
422 dreq->dreq_timestamp_echo = 0;
423 } else {
424 elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
425 tstamp_echo = htonl(dp->dccps_timestamp_echo);
426 dp->dccps_timestamp_echo = 0;
427 }
428
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300429 elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
430 len = 6 + elapsed_time_len;
431
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800432 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
433 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700434
435 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
436
437 to = skb_push(skb, len);
438 *to++ = DCCPO_TIMESTAMP_ECHO;
439 *to++ = len;
440
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700441 memcpy(to, &tstamp_echo, 4);
442 to += 4;
Andrea Bittauafe00252006-03-20 17:43:56 -0800443
Ian McDonald1bc09862005-08-20 00:23:43 -0300444 if (elapsed_time_len == 2) {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800445 const __be16 var16 = htons((u16)elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300446 memcpy(to, &var16, 2);
447 } else if (elapsed_time_len == 4) {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800448 const __be32 var32 = htonl(elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300449 memcpy(to, &var32, 4);
450 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700451
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800452 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700453}
454
Andrea Bittauafe00252006-03-20 17:43:56 -0800455static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900456 u8 *val, u8 len)
Andrea Bittauafe00252006-03-20 17:43:56 -0800457{
458 u8 *to;
459
460 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) {
Gerrit Renker59348b12006-11-20 18:39:23 -0200461 DCCP_WARN("packet too small for feature %d option!\n", feat);
Andrea Bittauafe00252006-03-20 17:43:56 -0800462 return -1;
463 }
464
465 DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
466
467 to = skb_push(skb, len + 3);
468 *to++ = type;
469 *to++ = len + 3;
470 *to++ = feat;
471
472 if (len)
473 memcpy(to, val, len);
Andrea Bittauafe00252006-03-20 17:43:56 -0800474
Gerrit Renkerc02fdc02006-11-14 12:48:10 -0200475 dccp_pr_debug("%s(%s (%d), ...), length %d\n",
476 dccp_feat_typename(type),
477 dccp_feat_name(feat), feat, len);
Andrea Bittauafe00252006-03-20 17:43:56 -0800478 return 0;
479}
480
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800481static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
Andrea Bittauafe00252006-03-20 17:43:56 -0800482{
483 struct dccp_sock *dp = dccp_sk(sk);
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800484 struct dccp_minisock *dmsk = dccp_msk(sk);
Andrea Bittauafe00252006-03-20 17:43:56 -0800485 struct dccp_opt_pend *opt, *next;
486 int change = 0;
487
488 /* confirm any options [NN opts] */
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800489 list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
Andrea Bittauafe00252006-03-20 17:43:56 -0800490 dccp_insert_feat_opt(skb, opt->dccpop_type,
491 opt->dccpop_feat, opt->dccpop_val,
492 opt->dccpop_len);
493 /* fear empty confirms */
494 if (opt->dccpop_val)
495 kfree(opt->dccpop_val);
496 kfree(opt);
497 }
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800498 INIT_LIST_HEAD(&dmsk->dccpms_conf);
Andrea Bittauafe00252006-03-20 17:43:56 -0800499
500 /* see which features we need to send */
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800501 list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
Andrea Bittauafe00252006-03-20 17:43:56 -0800502 /* see if we need to send any confirm */
503 if (opt->dccpop_sc) {
504 dccp_insert_feat_opt(skb, opt->dccpop_type + 1,
505 opt->dccpop_feat,
506 opt->dccpop_sc->dccpoc_val,
507 opt->dccpop_sc->dccpoc_len);
508
509 BUG_ON(!opt->dccpop_sc->dccpoc_val);
510 kfree(opt->dccpop_sc->dccpoc_val);
511 kfree(opt->dccpop_sc);
512 opt->dccpop_sc = NULL;
513 }
514
515 /* any option not confirmed, re-send it */
516 if (!opt->dccpop_conf) {
517 dccp_insert_feat_opt(skb, opt->dccpop_type,
518 opt->dccpop_feat, opt->dccpop_val,
519 opt->dccpop_len);
520 change++;
521 }
522 }
523
524 /* Retransmit timer.
525 * If this is the master listening sock, we don't set a timer on it. It
526 * should be fine because if the dude doesn't receive our RESPONSE
527 * [which will contain the CHANGE] he will send another REQUEST which
528 * will "retrnasmit" the change.
529 */
530 if (change && dp->dccps_role != DCCP_ROLE_LISTEN) {
531 dccp_pr_debug("reset feat negotiation timer %p\n", sk);
532
533 /* XXX don't reset the timer on re-transmissions. I.e. reset it
534 * only when sending new stuff i guess. Currently the timer
535 * never backs off because on re-transmission it just resets it!
536 */
537 inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
538 inet_csk(sk)->icsk_rto, DCCP_RTO_MAX);
539 }
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800540
541 return 0;
Andrea Bittauafe00252006-03-20 17:43:56 -0800542}
543
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200544/* The length of all options needs to be a multiple of 4 (5.8) */
545static void dccp_insert_option_padding(struct sk_buff *skb)
546{
547 int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
548
549 if (padding != 0) {
550 padding = 4 - padding;
551 memset(skb_push(skb, padding), 0, padding);
552 DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
553 }
554}
555
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800556int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700557{
558 struct dccp_sock *dp = dccp_sk(sk);
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800559 struct dccp_minisock *dmsk = dccp_msk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700560
561 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
562
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800563 if (dmsk->dccpms_send_ndp_count &&
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800564 dccp_insert_option_ndp(sk, skb))
565 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700566
567 if (!dccp_packet_without_ack(skb)) {
Arnaldo Carvalho de Meloa4bf3902006-03-20 22:50:58 -0800568 if (dmsk->dccpms_send_ack_vector &&
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800569 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
570 dccp_insert_option_ackvec(sk, skb))
571 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700572 }
573
Arnaldo Carvalho de Melo507d37c2005-09-09 02:30:07 -0300574 if (dp->dccps_hc_rx_insert_options) {
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800575 if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
576 return -1;
Arnaldo Carvalho de Melo507d37c2005-09-09 02:30:07 -0300577 dp->dccps_hc_rx_insert_options = 0;
578 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700579
Andrea Bittauafe00252006-03-20 17:43:56 -0800580 /* Feature negotiation */
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800581 /* Data packets can't do feat negotiation */
582 if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA &&
583 DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK &&
584 dccp_insert_options_feat(sk, skb))
585 return -1;
Andrea Bittauafe00252006-03-20 17:43:56 -0800586
Gerrit Renker89560b52007-03-20 15:27:17 -0300587 /*
588 * Obtain RTT sample from Request/Response exchange.
589 * This is currently used in CCID 3 initialisation.
590 */
591 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST &&
592 dccp_insert_option_timestamp(sk, skb))
593 return -1;
594
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200595 if (dp->dccps_timestamp_echo != 0 &&
596 dccp_insert_option_timestamp_echo(dp, NULL, skb))
597 return -1;
598
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200599 dccp_insert_option_padding(skb);
600 return 0;
601}
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700602
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200603int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
604{
605 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700606
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200607 if (dreq->dreq_timestamp_echo != 0 &&
608 dccp_insert_option_timestamp_echo(NULL, dreq, skb))
609 return -1;
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800610
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200611 dccp_insert_option_padding(skb);
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800612 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700613}