Commit | Line | Data |
---|---|---|
7c657876 ACM |
1 | /* |
2 | * net/dccp/options.c | |
3 | * | |
4 | * An implementation of the DCCP protocol | |
1bc09869 IM |
5 | * Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org> |
6 | * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net> | |
e6bccd35 | 7 | * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz> |
7c657876 ACM |
8 | * |
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 | */ | |
7c657876 ACM |
14 | #include <linux/dccp.h> |
15 | #include <linux/module.h> | |
16 | #include <linux/types.h> | |
76fd1e87 | 17 | #include <asm/unaligned.h> |
7c657876 ACM |
18 | #include <linux/kernel.h> |
19 | #include <linux/skbuff.h> | |
20 | ||
ae31c339 | 21 | #include "ackvec.h" |
7c657876 ACM |
22 | #include "ccid.h" |
23 | #include "dccp.h" | |
afe00251 | 24 | #include "feat.h" |
7c657876 | 25 | |
afb0a34d GR |
26 | int sysctl_dccp_feat_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW; |
27 | int sysctl_dccp_feat_rx_ccid = DCCPF_INITIAL_CCID; | |
28 | int sysctl_dccp_feat_tx_ccid = DCCPF_INITIAL_CCID; | |
29 | int sysctl_dccp_feat_ack_ratio = DCCPF_INITIAL_ACK_RATIO; | |
30 | int sysctl_dccp_feat_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR; | |
31 | int sysctl_dccp_feat_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT; | |
7c657876 | 32 | |
7c657876 ACM |
33 | static 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 | ||
8b819412 GR |
49 | /** |
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 | */ | |
54 | int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, | |
55 | struct sk_buff *skb) | |
7c657876 ACM |
56 | { |
57 | struct dccp_sock *dp = dccp_sk(sk); | |
7c657876 ACM |
58 | const struct dccp_hdr *dh = dccp_hdr(skb); |
59 | const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type; | |
bdf13d20 | 60 | u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; |
7c657876 ACM |
61 | unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb); |
62 | unsigned char *opt_ptr = options; | |
7690af3f ACM |
63 | const unsigned char *opt_end = (unsigned char *)dh + |
64 | (dh->dccph_doff * 4); | |
7c657876 ACM |
65 | struct dccp_options_received *opt_recv = &dp->dccps_options_received; |
66 | unsigned char opt, len; | |
67 | unsigned char *value; | |
1c14ac0a | 68 | u32 elapsed_time; |
76fd1e87 | 69 | __be32 opt_val; |
afe00251 AB |
70 | int rc; |
71 | int mandatory = 0; | |
7c657876 ACM |
72 | |
73 | memset(opt_recv, 0, sizeof(*opt_recv)); | |
74 | ||
fb950496 | 75 | opt = len = 0; |
7c657876 ACM |
76 | 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 | ||
8b819412 GR |
101 | /* |
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 | ||
7c657876 ACM |
115 | switch (opt) { |
116 | case DCCPO_PADDING: | |
117 | break; | |
afe00251 AB |
118 | case DCCPO_MANDATORY: |
119 | if (mandatory) | |
120 | goto out_invalid_option; | |
6df9424a ACM |
121 | if (pkt_type != DCCP_PKT_DATA) |
122 | mandatory = 1; | |
afe00251 | 123 | break; |
7c657876 ACM |
124 | 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); | |
09dbc389 | 129 | dccp_pr_debug("%s rx opt: NDP count=%d\n", dccp_role(sk), |
7690af3f | 130 | opt_recv->dccpor_ndp); |
7c657876 | 131 | break; |
afe00251 AB |
132 | case DCCPO_CHANGE_L: |
133 | /* fall through */ | |
134 | case DCCPO_CHANGE_R: | |
135 | if (len < 2) | |
136 | goto out_invalid_option; | |
137 | rc = dccp_feat_change_recv(sk, opt, *value, value + 1, | |
138 | len - 1); | |
139 | /* | |
140 | * When there is a change error, change_recv is | |
141 | * responsible for dealing with it. i.e. reply with an | |
142 | * empty confirm. | |
143 | * If the change was mandatory, then we need to die. | |
144 | */ | |
145 | if (rc && mandatory) | |
146 | goto out_invalid_option; | |
147 | break; | |
148 | case DCCPO_CONFIRM_L: | |
149 | /* fall through */ | |
150 | case DCCPO_CONFIRM_R: | |
151 | if (len < 2) | |
152 | goto out_invalid_option; | |
153 | if (dccp_feat_confirm_recv(sk, opt, *value, | |
154 | value + 1, len - 1)) | |
155 | goto out_invalid_option; | |
156 | break; | |
7c657876 | 157 | case DCCPO_ACK_VECTOR_0: |
ae31c339 | 158 | case DCCPO_ACK_VECTOR_1: |
c86ab2b6 | 159 | if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ |
e5a6de91 | 160 | break; |
7c657876 | 161 | |
a4bf3902 | 162 | if (dccp_msk(sk)->dccpms_send_ack_vector && |
bdf13d20 | 163 | dccp_ackvec_parse(sk, skb, &ackno, opt, value, len)) |
ae31c339 | 164 | goto out_invalid_option; |
7c657876 ACM |
165 | break; |
166 | case DCCPO_TIMESTAMP: | |
167 | if (len != 4) | |
168 | goto out_invalid_option; | |
b4d4f7c7 GR |
169 | /* |
170 | * RFC 4340 13.1: "The precise time corresponding to | |
171 | * Timestamp Value zero is not specified". We use | |
172 | * zero to indicate absence of a meaningful timestamp. | |
173 | */ | |
76fd1e87 | 174 | opt_val = get_unaligned((__be32 *)value); |
b4d4f7c7 GR |
175 | if (unlikely(opt_val == 0)) { |
176 | DCCP_WARN("Timestamp with zero value\n"); | |
177 | break; | |
178 | } | |
7c657876 | 179 | |
b4d4f7c7 GR |
180 | if (dreq != NULL) { |
181 | dreq->dreq_timestamp_echo = ntohl(opt_val); | |
182 | dreq->dreq_timestamp_time = dccp_timestamp(); | |
183 | } else { | |
184 | opt_recv->dccpor_timestamp = | |
185 | dp->dccps_timestamp_echo = ntohl(opt_val); | |
186 | dp->dccps_timestamp_time = dccp_timestamp(); | |
187 | } | |
09dbc389 | 188 | dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", |
b4d4f7c7 | 189 | dccp_role(sk), ntohl(opt_val), |
f6ccf554 | 190 | (unsigned long long) |
7c657876 ACM |
191 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
192 | break; | |
193 | case DCCPO_TIMESTAMP_ECHO: | |
1bc09869 | 194 | if (len != 4 && len != 6 && len != 8) |
7c657876 ACM |
195 | goto out_invalid_option; |
196 | ||
76fd1e87 GR |
197 | opt_val = get_unaligned((__be32 *)value); |
198 | opt_recv->dccpor_timestamp_echo = ntohl(opt_val); | |
7c657876 | 199 | |
09dbc389 | 200 | dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, " |
f73f7097 | 201 | "ackno=%llu", dccp_role(sk), |
7690af3f | 202 | opt_recv->dccpor_timestamp_echo, |
f6ccf554 DM |
203 | len + 2, |
204 | (unsigned long long) | |
1bc09869 IM |
205 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
206 | ||
76fd1e87 | 207 | value += 4; |
1bc09869 | 208 | |
76fd1e87 | 209 | if (len == 4) { /* no elapsed time included */ |
f73f7097 | 210 | dccp_pr_debug_cat("\n"); |
1c14ac0a | 211 | break; |
f73f7097 | 212 | } |
1c14ac0a | 213 | |
76fd1e87 GR |
214 | if (len == 6) { /* 2-byte elapsed time */ |
215 | __be16 opt_val2 = get_unaligned((__be16 *)value); | |
216 | elapsed_time = ntohs(opt_val2); | |
217 | } else { /* 4-byte elapsed time */ | |
218 | opt_val = get_unaligned((__be32 *)value); | |
219 | elapsed_time = ntohl(opt_val); | |
220 | } | |
1c14ac0a | 221 | |
dcad856f | 222 | dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time); |
f73f7097 | 223 | |
1c14ac0a ACM |
224 | /* Give precedence to the biggest ELAPSED_TIME */ |
225 | if (elapsed_time > opt_recv->dccpor_elapsed_time) | |
226 | opt_recv->dccpor_elapsed_time = elapsed_time; | |
7c657876 ACM |
227 | break; |
228 | case DCCPO_ELAPSED_TIME: | |
c86ab2b6 GR |
229 | if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ |
230 | break; | |
1bc09869 | 231 | |
76fd1e87 GR |
232 | if (len == 2) { |
233 | __be16 opt_val2 = get_unaligned((__be16 *)value); | |
234 | elapsed_time = ntohs(opt_val2); | |
c86ab2b6 | 235 | } else if (len == 4) { |
76fd1e87 GR |
236 | opt_val = get_unaligned((__be32 *)value); |
237 | elapsed_time = ntohl(opt_val); | |
c86ab2b6 GR |
238 | } else { |
239 | goto out_invalid_option; | |
76fd1e87 | 240 | } |
1c14ac0a ACM |
241 | |
242 | if (elapsed_time > opt_recv->dccpor_elapsed_time) | |
243 | opt_recv->dccpor_elapsed_time = elapsed_time; | |
1bc09869 | 244 | |
09dbc389 GR |
245 | dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", |
246 | dccp_role(sk), elapsed_time); | |
7c657876 | 247 | break; |
7c657876 ACM |
248 | case 128 ... 191: { |
249 | const u16 idx = value - options; | |
250 | ||
7690af3f ACM |
251 | if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk, |
252 | opt, len, idx, | |
253 | value) != 0) | |
7c657876 ACM |
254 | goto out_invalid_option; |
255 | } | |
256 | break; | |
257 | case 192 ... 255: { | |
258 | const u16 idx = value - options; | |
259 | ||
7690af3f ACM |
260 | if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk, |
261 | opt, len, idx, | |
262 | value) != 0) | |
7c657876 ACM |
263 | goto out_invalid_option; |
264 | } | |
265 | break; | |
266 | default: | |
59348b19 GR |
267 | DCCP_CRIT("DCCP(%p): option %d(len=%d) not " |
268 | "implemented, ignoring", sk, opt, len); | |
7c657876 | 269 | break; |
c9eaf173 | 270 | } |
8b819412 | 271 | ignore_option: |
afe00251 AB |
272 | if (opt != DCCPO_MANDATORY) |
273 | mandatory = 0; | |
7c657876 ACM |
274 | } |
275 | ||
6df9424a ACM |
276 | /* mandatory was the last byte in option list -> reset connection */ |
277 | if (mandatory) | |
278 | goto out_invalid_option; | |
279 | ||
7c657876 ACM |
280 | return 0; |
281 | ||
282 | out_invalid_option: | |
283 | DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT); | |
284 | DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR; | |
59348b19 | 285 | DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len); |
7c657876 ACM |
286 | return -1; |
287 | } | |
288 | ||
b61fafc4 ACM |
289 | EXPORT_SYMBOL_GPL(dccp_parse_options); |
290 | ||
7c657876 ACM |
291 | static void dccp_encode_value_var(const u32 value, unsigned char *to, |
292 | const unsigned int len) | |
293 | { | |
294 | if (len > 3) | |
295 | *to++ = (value & 0xFF000000) >> 24; | |
296 | if (len > 2) | |
297 | *to++ = (value & 0xFF0000) >> 16; | |
298 | if (len > 1) | |
299 | *to++ = (value & 0xFF00) >> 8; | |
300 | if (len > 0) | |
301 | *to++ = (value & 0xFF); | |
302 | } | |
303 | ||
304 | static inline int dccp_ndp_len(const int ndp) | |
305 | { | |
306 | return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3; | |
307 | } | |
308 | ||
2d0817d1 | 309 | int dccp_insert_option(struct sock *sk, struct sk_buff *skb, |
7c657876 ACM |
310 | const unsigned char option, |
311 | const void *value, const unsigned char len) | |
312 | { | |
313 | unsigned char *to; | |
314 | ||
2d0817d1 ACM |
315 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) |
316 | return -1; | |
7c657876 ACM |
317 | |
318 | DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2; | |
319 | ||
320 | to = skb_push(skb, len + 2); | |
321 | *to++ = option; | |
322 | *to++ = len + 2; | |
323 | ||
324 | memcpy(to, value, len); | |
2d0817d1 | 325 | return 0; |
7c657876 ACM |
326 | } |
327 | ||
328 | EXPORT_SYMBOL_GPL(dccp_insert_option); | |
329 | ||
2d0817d1 | 330 | static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
331 | { |
332 | struct dccp_sock *dp = dccp_sk(sk); | |
333 | int ndp = dp->dccps_ndp_count; | |
334 | ||
335 | if (dccp_non_data_packet(skb)) | |
336 | ++dp->dccps_ndp_count; | |
337 | else | |
338 | dp->dccps_ndp_count = 0; | |
339 | ||
340 | if (ndp > 0) { | |
341 | unsigned char *ptr; | |
342 | const int ndp_len = dccp_ndp_len(ndp); | |
343 | const int len = ndp_len + 2; | |
344 | ||
345 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) | |
2d0817d1 | 346 | return -1; |
7c657876 ACM |
347 | |
348 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
349 | ||
350 | ptr = skb_push(skb, len); | |
351 | *ptr++ = DCCPO_NDP_COUNT; | |
352 | *ptr++ = len; | |
353 | dccp_encode_value_var(ndp, ptr, ndp_len); | |
354 | } | |
2d0817d1 ACM |
355 | |
356 | return 0; | |
7c657876 ACM |
357 | } |
358 | ||
359 | static inline int dccp_elapsed_time_len(const u32 elapsed_time) | |
360 | { | |
b1c9fe7b | 361 | return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; |
7c657876 ACM |
362 | } |
363 | ||
2d0817d1 ACM |
364 | int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb, |
365 | u32 elapsed_time) | |
7c657876 | 366 | { |
7c657876 ACM |
367 | const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); |
368 | const int len = 2 + elapsed_time_len; | |
369 | unsigned char *to; | |
370 | ||
1bc09869 | 371 | if (elapsed_time_len == 0) |
2d0817d1 | 372 | return 0; |
7c657876 | 373 | |
2d0817d1 ACM |
374 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) |
375 | return -1; | |
7c657876 ACM |
376 | |
377 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
378 | ||
379 | to = skb_push(skb, len); | |
380 | *to++ = DCCPO_ELAPSED_TIME; | |
381 | *to++ = len; | |
382 | ||
1bc09869 | 383 | if (elapsed_time_len == 2) { |
60fe62e7 | 384 | const __be16 var16 = htons((u16)elapsed_time); |
1bc09869 IM |
385 | memcpy(to, &var16, 2); |
386 | } else { | |
60fe62e7 | 387 | const __be32 var32 = htonl(elapsed_time); |
1bc09869 IM |
388 | memcpy(to, &var32, 4); |
389 | } | |
7c657876 | 390 | |
2d0817d1 | 391 | return 0; |
7c657876 ACM |
392 | } |
393 | ||
d4b81ff7 | 394 | EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); |
7c657876 | 395 | |
2d0817d1 | 396 | int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb) |
7c657876 | 397 | { |
4c70f383 | 398 | __be32 now = htonl(dccp_timestamp()); |
1bc09869 IM |
399 | /* yes this will overflow but that is the point as we want a |
400 | * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ | |
401 | ||
2d0817d1 | 402 | return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now)); |
7c657876 ACM |
403 | } |
404 | ||
d4b81ff7 ACM |
405 | EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp); |
406 | ||
b4d4f7c7 GR |
407 | static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, |
408 | struct dccp_request_sock *dreq, | |
2d0817d1 | 409 | struct sk_buff *skb) |
7c657876 | 410 | { |
60fe62e7 | 411 | __be32 tstamp_echo; |
7c657876 | 412 | unsigned char *to; |
b4d4f7c7 GR |
413 | u32 elapsed_time, elapsed_time_len, len; |
414 | ||
415 | if (dreq != NULL) { | |
416 | elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; | |
417 | tstamp_echo = htonl(dreq->dreq_timestamp_echo); | |
418 | dreq->dreq_timestamp_echo = 0; | |
419 | } else { | |
420 | elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; | |
421 | tstamp_echo = htonl(dp->dccps_timestamp_echo); | |
422 | dp->dccps_timestamp_echo = 0; | |
423 | } | |
424 | ||
b0e56780 ACM |
425 | elapsed_time_len = dccp_elapsed_time_len(elapsed_time); |
426 | len = 6 + elapsed_time_len; | |
427 | ||
2d0817d1 ACM |
428 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) |
429 | return -1; | |
7c657876 ACM |
430 | |
431 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
432 | ||
433 | to = skb_push(skb, len); | |
434 | *to++ = DCCPO_TIMESTAMP_ECHO; | |
435 | *to++ = len; | |
436 | ||
7c657876 ACM |
437 | memcpy(to, &tstamp_echo, 4); |
438 | to += 4; | |
afe00251 | 439 | |
1bc09869 | 440 | if (elapsed_time_len == 2) { |
60fe62e7 | 441 | const __be16 var16 = htons((u16)elapsed_time); |
1bc09869 IM |
442 | memcpy(to, &var16, 2); |
443 | } else if (elapsed_time_len == 4) { | |
60fe62e7 | 444 | const __be32 var32 = htonl(elapsed_time); |
1bc09869 IM |
445 | memcpy(to, &var32, 4); |
446 | } | |
7c657876 | 447 | |
2d0817d1 | 448 | return 0; |
7c657876 ACM |
449 | } |
450 | ||
afe00251 | 451 | static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat, |
c9eaf173 | 452 | u8 *val, u8 len) |
afe00251 AB |
453 | { |
454 | u8 *to; | |
455 | ||
456 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) { | |
59348b19 | 457 | DCCP_WARN("packet too small for feature %d option!\n", feat); |
afe00251 AB |
458 | return -1; |
459 | } | |
460 | ||
461 | DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3; | |
462 | ||
463 | to = skb_push(skb, len + 3); | |
464 | *to++ = type; | |
465 | *to++ = len + 3; | |
466 | *to++ = feat; | |
467 | ||
468 | if (len) | |
469 | memcpy(to, val, len); | |
afe00251 | 470 | |
c02fdc0e GR |
471 | dccp_pr_debug("%s(%s (%d), ...), length %d\n", |
472 | dccp_feat_typename(type), | |
473 | dccp_feat_name(feat), feat, len); | |
afe00251 AB |
474 | return 0; |
475 | } | |
476 | ||
2d0817d1 | 477 | static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb) |
afe00251 AB |
478 | { |
479 | struct dccp_sock *dp = dccp_sk(sk); | |
a4bf3902 | 480 | struct dccp_minisock *dmsk = dccp_msk(sk); |
afe00251 AB |
481 | struct dccp_opt_pend *opt, *next; |
482 | int change = 0; | |
483 | ||
484 | /* confirm any options [NN opts] */ | |
a4bf3902 | 485 | list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) { |
afe00251 AB |
486 | dccp_insert_feat_opt(skb, opt->dccpop_type, |
487 | opt->dccpop_feat, opt->dccpop_val, | |
488 | opt->dccpop_len); | |
489 | /* fear empty confirms */ | |
490 | if (opt->dccpop_val) | |
491 | kfree(opt->dccpop_val); | |
492 | kfree(opt); | |
493 | } | |
a4bf3902 | 494 | INIT_LIST_HEAD(&dmsk->dccpms_conf); |
afe00251 AB |
495 | |
496 | /* see which features we need to send */ | |
a4bf3902 | 497 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
498 | /* see if we need to send any confirm */ |
499 | if (opt->dccpop_sc) { | |
500 | dccp_insert_feat_opt(skb, opt->dccpop_type + 1, | |
501 | opt->dccpop_feat, | |
502 | opt->dccpop_sc->dccpoc_val, | |
503 | opt->dccpop_sc->dccpoc_len); | |
504 | ||
505 | BUG_ON(!opt->dccpop_sc->dccpoc_val); | |
506 | kfree(opt->dccpop_sc->dccpoc_val); | |
507 | kfree(opt->dccpop_sc); | |
508 | opt->dccpop_sc = NULL; | |
509 | } | |
510 | ||
511 | /* any option not confirmed, re-send it */ | |
512 | if (!opt->dccpop_conf) { | |
513 | dccp_insert_feat_opt(skb, opt->dccpop_type, | |
514 | opt->dccpop_feat, opt->dccpop_val, | |
515 | opt->dccpop_len); | |
516 | change++; | |
517 | } | |
518 | } | |
519 | ||
520 | /* Retransmit timer. | |
521 | * If this is the master listening sock, we don't set a timer on it. It | |
522 | * should be fine because if the dude doesn't receive our RESPONSE | |
523 | * [which will contain the CHANGE] he will send another REQUEST which | |
524 | * will "retrnasmit" the change. | |
525 | */ | |
526 | if (change && dp->dccps_role != DCCP_ROLE_LISTEN) { | |
527 | dccp_pr_debug("reset feat negotiation timer %p\n", sk); | |
528 | ||
529 | /* XXX don't reset the timer on re-transmissions. I.e. reset it | |
530 | * only when sending new stuff i guess. Currently the timer | |
531 | * never backs off because on re-transmission it just resets it! | |
532 | */ | |
533 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, | |
534 | inet_csk(sk)->icsk_rto, DCCP_RTO_MAX); | |
535 | } | |
2d0817d1 ACM |
536 | |
537 | return 0; | |
afe00251 AB |
538 | } |
539 | ||
af3b867e GR |
540 | /* The length of all options needs to be a multiple of 4 (5.8) */ |
541 | static void dccp_insert_option_padding(struct sk_buff *skb) | |
542 | { | |
543 | int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; | |
544 | ||
545 | if (padding != 0) { | |
546 | padding = 4 - padding; | |
547 | memset(skb_push(skb, padding), 0, padding); | |
548 | DCCP_SKB_CB(skb)->dccpd_opt_len += padding; | |
549 | } | |
550 | } | |
551 | ||
2d0817d1 | 552 | int dccp_insert_options(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
553 | { |
554 | struct dccp_sock *dp = dccp_sk(sk); | |
a4bf3902 | 555 | struct dccp_minisock *dmsk = dccp_msk(sk); |
7c657876 ACM |
556 | |
557 | DCCP_SKB_CB(skb)->dccpd_opt_len = 0; | |
558 | ||
a4bf3902 | 559 | if (dmsk->dccpms_send_ndp_count && |
2d0817d1 ACM |
560 | dccp_insert_option_ndp(sk, skb)) |
561 | return -1; | |
7c657876 ACM |
562 | |
563 | if (!dccp_packet_without_ack(skb)) { | |
a4bf3902 | 564 | if (dmsk->dccpms_send_ack_vector && |
2d0817d1 ACM |
565 | dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) && |
566 | dccp_insert_option_ackvec(sk, skb)) | |
567 | return -1; | |
7c657876 ACM |
568 | } |
569 | ||
507d37cf | 570 | if (dp->dccps_hc_rx_insert_options) { |
2d0817d1 ACM |
571 | if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb)) |
572 | return -1; | |
507d37cf ACM |
573 | dp->dccps_hc_rx_insert_options = 0; |
574 | } | |
7c657876 | 575 | |
afe00251 | 576 | /* Feature negotiation */ |
2d0817d1 ACM |
577 | /* Data packets can't do feat negotiation */ |
578 | if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA && | |
579 | DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK && | |
580 | dccp_insert_options_feat(sk, skb)) | |
581 | return -1; | |
afe00251 | 582 | |
89560b53 GR |
583 | /* |
584 | * Obtain RTT sample from Request/Response exchange. | |
585 | * This is currently used in CCID 3 initialisation. | |
586 | */ | |
587 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST && | |
588 | dccp_insert_option_timestamp(sk, skb)) | |
589 | return -1; | |
590 | ||
b4d4f7c7 GR |
591 | if (dp->dccps_timestamp_echo != 0 && |
592 | dccp_insert_option_timestamp_echo(dp, NULL, skb)) | |
593 | return -1; | |
594 | ||
af3b867e GR |
595 | dccp_insert_option_padding(skb); |
596 | return 0; | |
597 | } | |
7c657876 | 598 | |
af3b867e GR |
599 | int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) |
600 | { | |
601 | DCCP_SKB_CB(skb)->dccpd_opt_len = 0; | |
7c657876 | 602 | |
af3b867e GR |
603 | if (dreq->dreq_timestamp_echo != 0 && |
604 | dccp_insert_option_timestamp_echo(NULL, dreq, skb)) | |
605 | return -1; | |
2d0817d1 | 606 | |
af3b867e | 607 | dccp_insert_option_padding(skb); |
2d0817d1 | 608 | return 0; |
7c657876 | 609 | } |