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). | |
65907a43 | 110 | * The same applies to Ack Vectors, as these depend on the CCID. |
8b819412 GR |
111 | * |
112 | */ | |
65907a43 GR |
113 | if (dreq != NULL && (opt >= 128 || |
114 | opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1)) | |
8b819412 GR |
115 | goto ignore_option; |
116 | ||
7c657876 ACM |
117 | switch (opt) { |
118 | case DCCPO_PADDING: | |
119 | break; | |
afe00251 AB |
120 | case DCCPO_MANDATORY: |
121 | if (mandatory) | |
122 | goto out_invalid_option; | |
6df9424a ACM |
123 | if (pkt_type != DCCP_PKT_DATA) |
124 | mandatory = 1; | |
afe00251 | 125 | break; |
7c657876 | 126 | case DCCPO_NDP_COUNT: |
5b5d0e70 | 127 | if (len > 6) |
7c657876 ACM |
128 | goto out_invalid_option; |
129 | ||
130 | opt_recv->dccpor_ndp = dccp_decode_value_var(value, len); | |
5b5d0e70 GR |
131 | dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk), |
132 | (unsigned long long)opt_recv->dccpor_ndp); | |
7c657876 | 133 | break; |
afe00251 AB |
134 | case DCCPO_CHANGE_L: |
135 | /* fall through */ | |
136 | case DCCPO_CHANGE_R: | |
cf86314c GR |
137 | if (pkt_type == DCCP_PKT_DATA) |
138 | break; | |
afe00251 AB |
139 | if (len < 2) |
140 | goto out_invalid_option; | |
141 | rc = dccp_feat_change_recv(sk, opt, *value, value + 1, | |
142 | len - 1); | |
143 | /* | |
144 | * When there is a change error, change_recv is | |
145 | * responsible for dealing with it. i.e. reply with an | |
146 | * empty confirm. | |
147 | * If the change was mandatory, then we need to die. | |
148 | */ | |
149 | if (rc && mandatory) | |
150 | goto out_invalid_option; | |
151 | break; | |
152 | case DCCPO_CONFIRM_L: | |
153 | /* fall through */ | |
154 | case DCCPO_CONFIRM_R: | |
cf86314c GR |
155 | if (pkt_type == DCCP_PKT_DATA) |
156 | break; | |
157 | if (len < 2) /* FIXME this disallows empty confirm */ | |
afe00251 AB |
158 | goto out_invalid_option; |
159 | if (dccp_feat_confirm_recv(sk, opt, *value, | |
160 | value + 1, len - 1)) | |
161 | goto out_invalid_option; | |
162 | break; | |
7c657876 | 163 | case DCCPO_ACK_VECTOR_0: |
ae31c339 | 164 | case DCCPO_ACK_VECTOR_1: |
c86ab2b6 | 165 | if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ |
e5a6de91 | 166 | break; |
7c657876 | 167 | |
a4bf3902 | 168 | if (dccp_msk(sk)->dccpms_send_ack_vector && |
bdf13d20 | 169 | dccp_ackvec_parse(sk, skb, &ackno, opt, value, len)) |
ae31c339 | 170 | goto out_invalid_option; |
7c657876 ACM |
171 | break; |
172 | case DCCPO_TIMESTAMP: | |
173 | if (len != 4) | |
174 | goto out_invalid_option; | |
b4d4f7c7 GR |
175 | /* |
176 | * RFC 4340 13.1: "The precise time corresponding to | |
177 | * Timestamp Value zero is not specified". We use | |
178 | * zero to indicate absence of a meaningful timestamp. | |
179 | */ | |
76fd1e87 | 180 | opt_val = get_unaligned((__be32 *)value); |
b4d4f7c7 GR |
181 | if (unlikely(opt_val == 0)) { |
182 | DCCP_WARN("Timestamp with zero value\n"); | |
183 | break; | |
184 | } | |
7c657876 | 185 | |
b4d4f7c7 GR |
186 | if (dreq != NULL) { |
187 | dreq->dreq_timestamp_echo = ntohl(opt_val); | |
188 | dreq->dreq_timestamp_time = dccp_timestamp(); | |
189 | } else { | |
190 | opt_recv->dccpor_timestamp = | |
191 | dp->dccps_timestamp_echo = ntohl(opt_val); | |
192 | dp->dccps_timestamp_time = dccp_timestamp(); | |
193 | } | |
09dbc389 | 194 | dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", |
b4d4f7c7 | 195 | dccp_role(sk), ntohl(opt_val), |
f6ccf554 | 196 | (unsigned long long) |
7c657876 ACM |
197 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
198 | break; | |
199 | case DCCPO_TIMESTAMP_ECHO: | |
1bc09869 | 200 | if (len != 4 && len != 6 && len != 8) |
7c657876 ACM |
201 | goto out_invalid_option; |
202 | ||
76fd1e87 GR |
203 | opt_val = get_unaligned((__be32 *)value); |
204 | opt_recv->dccpor_timestamp_echo = ntohl(opt_val); | |
7c657876 | 205 | |
09dbc389 | 206 | dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, " |
f73f7097 | 207 | "ackno=%llu", dccp_role(sk), |
7690af3f | 208 | opt_recv->dccpor_timestamp_echo, |
f6ccf554 DM |
209 | len + 2, |
210 | (unsigned long long) | |
1bc09869 IM |
211 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
212 | ||
76fd1e87 | 213 | value += 4; |
1bc09869 | 214 | |
76fd1e87 | 215 | if (len == 4) { /* no elapsed time included */ |
f73f7097 | 216 | dccp_pr_debug_cat("\n"); |
1c14ac0a | 217 | break; |
f73f7097 | 218 | } |
1c14ac0a | 219 | |
76fd1e87 GR |
220 | if (len == 6) { /* 2-byte elapsed time */ |
221 | __be16 opt_val2 = get_unaligned((__be16 *)value); | |
222 | elapsed_time = ntohs(opt_val2); | |
223 | } else { /* 4-byte elapsed time */ | |
224 | opt_val = get_unaligned((__be32 *)value); | |
225 | elapsed_time = ntohl(opt_val); | |
226 | } | |
1c14ac0a | 227 | |
dcad856f | 228 | dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time); |
f73f7097 | 229 | |
1c14ac0a ACM |
230 | /* Give precedence to the biggest ELAPSED_TIME */ |
231 | if (elapsed_time > opt_recv->dccpor_elapsed_time) | |
232 | opt_recv->dccpor_elapsed_time = elapsed_time; | |
7c657876 ACM |
233 | break; |
234 | case DCCPO_ELAPSED_TIME: | |
c86ab2b6 GR |
235 | if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ |
236 | break; | |
1bc09869 | 237 | |
76fd1e87 GR |
238 | if (len == 2) { |
239 | __be16 opt_val2 = get_unaligned((__be16 *)value); | |
240 | elapsed_time = ntohs(opt_val2); | |
c86ab2b6 | 241 | } else if (len == 4) { |
76fd1e87 GR |
242 | opt_val = get_unaligned((__be32 *)value); |
243 | elapsed_time = ntohl(opt_val); | |
c86ab2b6 GR |
244 | } else { |
245 | goto out_invalid_option; | |
76fd1e87 | 246 | } |
1c14ac0a ACM |
247 | |
248 | if (elapsed_time > opt_recv->dccpor_elapsed_time) | |
249 | opt_recv->dccpor_elapsed_time = elapsed_time; | |
1bc09869 | 250 | |
09dbc389 GR |
251 | dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", |
252 | dccp_role(sk), elapsed_time); | |
7c657876 | 253 | break; |
7c657876 ACM |
254 | case 128 ... 191: { |
255 | const u16 idx = value - options; | |
256 | ||
7690af3f ACM |
257 | if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk, |
258 | opt, len, idx, | |
259 | value) != 0) | |
7c657876 ACM |
260 | goto out_invalid_option; |
261 | } | |
262 | break; | |
263 | case 192 ... 255: { | |
264 | const u16 idx = value - options; | |
265 | ||
7690af3f ACM |
266 | if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk, |
267 | opt, len, idx, | |
268 | value) != 0) | |
7c657876 ACM |
269 | goto out_invalid_option; |
270 | } | |
271 | break; | |
272 | default: | |
59348b19 GR |
273 | DCCP_CRIT("DCCP(%p): option %d(len=%d) not " |
274 | "implemented, ignoring", sk, opt, len); | |
7c657876 | 275 | break; |
c9eaf173 | 276 | } |
8b819412 | 277 | ignore_option: |
afe00251 AB |
278 | if (opt != DCCPO_MANDATORY) |
279 | mandatory = 0; | |
7c657876 ACM |
280 | } |
281 | ||
6df9424a ACM |
282 | /* mandatory was the last byte in option list -> reset connection */ |
283 | if (mandatory) | |
284 | goto out_invalid_option; | |
285 | ||
7c657876 ACM |
286 | return 0; |
287 | ||
288 | out_invalid_option: | |
289 | DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT); | |
290 | DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR; | |
59348b19 | 291 | DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len); |
7c657876 ACM |
292 | return -1; |
293 | } | |
294 | ||
b61fafc4 ACM |
295 | EXPORT_SYMBOL_GPL(dccp_parse_options); |
296 | ||
7c657876 ACM |
297 | static void dccp_encode_value_var(const u32 value, unsigned char *to, |
298 | const unsigned int len) | |
299 | { | |
300 | if (len > 3) | |
301 | *to++ = (value & 0xFF000000) >> 24; | |
302 | if (len > 2) | |
303 | *to++ = (value & 0xFF0000) >> 16; | |
304 | if (len > 1) | |
305 | *to++ = (value & 0xFF00) >> 8; | |
306 | if (len > 0) | |
307 | *to++ = (value & 0xFF); | |
308 | } | |
309 | ||
5b5d0e70 | 310 | static inline u8 dccp_ndp_len(const u64 ndp) |
7c657876 | 311 | { |
5b5d0e70 GR |
312 | if (likely(ndp <= 0xFF)) |
313 | return 1; | |
314 | return likely(ndp <= USHORT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6); | |
7c657876 ACM |
315 | } |
316 | ||
2d0817d1 | 317 | int dccp_insert_option(struct sock *sk, struct sk_buff *skb, |
7c657876 ACM |
318 | const unsigned char option, |
319 | const void *value, const unsigned char len) | |
320 | { | |
321 | unsigned char *to; | |
322 | ||
2d0817d1 ACM |
323 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) |
324 | return -1; | |
7c657876 ACM |
325 | |
326 | DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2; | |
327 | ||
328 | to = skb_push(skb, len + 2); | |
329 | *to++ = option; | |
330 | *to++ = len + 2; | |
331 | ||
332 | memcpy(to, value, len); | |
2d0817d1 | 333 | return 0; |
7c657876 ACM |
334 | } |
335 | ||
336 | EXPORT_SYMBOL_GPL(dccp_insert_option); | |
337 | ||
2d0817d1 | 338 | static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
339 | { |
340 | struct dccp_sock *dp = dccp_sk(sk); | |
5b5d0e70 | 341 | u64 ndp = dp->dccps_ndp_count; |
7c657876 ACM |
342 | |
343 | if (dccp_non_data_packet(skb)) | |
344 | ++dp->dccps_ndp_count; | |
345 | else | |
346 | dp->dccps_ndp_count = 0; | |
347 | ||
348 | if (ndp > 0) { | |
349 | unsigned char *ptr; | |
350 | const int ndp_len = dccp_ndp_len(ndp); | |
351 | const int len = ndp_len + 2; | |
352 | ||
353 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) | |
2d0817d1 | 354 | return -1; |
7c657876 ACM |
355 | |
356 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
357 | ||
358 | ptr = skb_push(skb, len); | |
359 | *ptr++ = DCCPO_NDP_COUNT; | |
360 | *ptr++ = len; | |
361 | dccp_encode_value_var(ndp, ptr, ndp_len); | |
362 | } | |
2d0817d1 ACM |
363 | |
364 | return 0; | |
7c657876 ACM |
365 | } |
366 | ||
367 | static inline int dccp_elapsed_time_len(const u32 elapsed_time) | |
368 | { | |
b1c9fe7b | 369 | return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; |
7c657876 ACM |
370 | } |
371 | ||
2d0817d1 ACM |
372 | int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb, |
373 | u32 elapsed_time) | |
7c657876 | 374 | { |
7c657876 ACM |
375 | const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); |
376 | const int len = 2 + elapsed_time_len; | |
377 | unsigned char *to; | |
378 | ||
1bc09869 | 379 | if (elapsed_time_len == 0) |
2d0817d1 | 380 | return 0; |
7c657876 | 381 | |
2d0817d1 ACM |
382 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) |
383 | return -1; | |
7c657876 ACM |
384 | |
385 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
386 | ||
387 | to = skb_push(skb, len); | |
388 | *to++ = DCCPO_ELAPSED_TIME; | |
389 | *to++ = len; | |
390 | ||
1bc09869 | 391 | if (elapsed_time_len == 2) { |
60fe62e7 | 392 | const __be16 var16 = htons((u16)elapsed_time); |
1bc09869 IM |
393 | memcpy(to, &var16, 2); |
394 | } else { | |
60fe62e7 | 395 | const __be32 var32 = htonl(elapsed_time); |
1bc09869 IM |
396 | memcpy(to, &var32, 4); |
397 | } | |
7c657876 | 398 | |
2d0817d1 | 399 | return 0; |
7c657876 ACM |
400 | } |
401 | ||
d4b81ff7 | 402 | EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); |
7c657876 | 403 | |
2d0817d1 | 404 | int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb) |
7c657876 | 405 | { |
4c70f383 | 406 | __be32 now = htonl(dccp_timestamp()); |
1bc09869 IM |
407 | /* yes this will overflow but that is the point as we want a |
408 | * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ | |
409 | ||
2d0817d1 | 410 | return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now)); |
7c657876 ACM |
411 | } |
412 | ||
d4b81ff7 ACM |
413 | EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp); |
414 | ||
b4d4f7c7 GR |
415 | static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, |
416 | struct dccp_request_sock *dreq, | |
2d0817d1 | 417 | struct sk_buff *skb) |
7c657876 | 418 | { |
60fe62e7 | 419 | __be32 tstamp_echo; |
7c657876 | 420 | unsigned char *to; |
b4d4f7c7 GR |
421 | u32 elapsed_time, elapsed_time_len, len; |
422 | ||
423 | if (dreq != NULL) { | |
424 | elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; | |
425 | tstamp_echo = htonl(dreq->dreq_timestamp_echo); | |
426 | dreq->dreq_timestamp_echo = 0; | |
427 | } else { | |
428 | elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; | |
429 | tstamp_echo = htonl(dp->dccps_timestamp_echo); | |
430 | dp->dccps_timestamp_echo = 0; | |
431 | } | |
432 | ||
b0e56780 ACM |
433 | elapsed_time_len = dccp_elapsed_time_len(elapsed_time); |
434 | len = 6 + elapsed_time_len; | |
435 | ||
2d0817d1 ACM |
436 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) |
437 | return -1; | |
7c657876 ACM |
438 | |
439 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
440 | ||
441 | to = skb_push(skb, len); | |
442 | *to++ = DCCPO_TIMESTAMP_ECHO; | |
443 | *to++ = len; | |
444 | ||
7c657876 ACM |
445 | memcpy(to, &tstamp_echo, 4); |
446 | to += 4; | |
afe00251 | 447 | |
1bc09869 | 448 | if (elapsed_time_len == 2) { |
60fe62e7 | 449 | const __be16 var16 = htons((u16)elapsed_time); |
1bc09869 IM |
450 | memcpy(to, &var16, 2); |
451 | } else if (elapsed_time_len == 4) { | |
60fe62e7 | 452 | const __be32 var32 = htonl(elapsed_time); |
1bc09869 IM |
453 | memcpy(to, &var32, 4); |
454 | } | |
7c657876 | 455 | |
2d0817d1 | 456 | return 0; |
7c657876 ACM |
457 | } |
458 | ||
afe00251 | 459 | static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat, |
c9eaf173 | 460 | u8 *val, u8 len) |
afe00251 AB |
461 | { |
462 | u8 *to; | |
463 | ||
464 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) { | |
59348b19 | 465 | DCCP_WARN("packet too small for feature %d option!\n", feat); |
afe00251 AB |
466 | return -1; |
467 | } | |
468 | ||
469 | DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3; | |
470 | ||
471 | to = skb_push(skb, len + 3); | |
472 | *to++ = type; | |
473 | *to++ = len + 3; | |
474 | *to++ = feat; | |
475 | ||
476 | if (len) | |
477 | memcpy(to, val, len); | |
afe00251 | 478 | |
c02fdc0e GR |
479 | dccp_pr_debug("%s(%s (%d), ...), length %d\n", |
480 | dccp_feat_typename(type), | |
481 | dccp_feat_name(feat), feat, len); | |
afe00251 AB |
482 | return 0; |
483 | } | |
484 | ||
2d0817d1 | 485 | static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb) |
afe00251 AB |
486 | { |
487 | struct dccp_sock *dp = dccp_sk(sk); | |
a4bf3902 | 488 | struct dccp_minisock *dmsk = dccp_msk(sk); |
afe00251 AB |
489 | struct dccp_opt_pend *opt, *next; |
490 | int change = 0; | |
491 | ||
492 | /* confirm any options [NN opts] */ | |
a4bf3902 | 493 | list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) { |
afe00251 AB |
494 | dccp_insert_feat_opt(skb, opt->dccpop_type, |
495 | opt->dccpop_feat, opt->dccpop_val, | |
496 | opt->dccpop_len); | |
497 | /* fear empty confirms */ | |
498 | if (opt->dccpop_val) | |
499 | kfree(opt->dccpop_val); | |
500 | kfree(opt); | |
501 | } | |
a4bf3902 | 502 | INIT_LIST_HEAD(&dmsk->dccpms_conf); |
afe00251 AB |
503 | |
504 | /* see which features we need to send */ | |
a4bf3902 | 505 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
506 | /* see if we need to send any confirm */ |
507 | if (opt->dccpop_sc) { | |
508 | dccp_insert_feat_opt(skb, opt->dccpop_type + 1, | |
509 | opt->dccpop_feat, | |
510 | opt->dccpop_sc->dccpoc_val, | |
511 | opt->dccpop_sc->dccpoc_len); | |
512 | ||
513 | BUG_ON(!opt->dccpop_sc->dccpoc_val); | |
514 | kfree(opt->dccpop_sc->dccpoc_val); | |
515 | kfree(opt->dccpop_sc); | |
516 | opt->dccpop_sc = NULL; | |
517 | } | |
518 | ||
519 | /* any option not confirmed, re-send it */ | |
520 | if (!opt->dccpop_conf) { | |
521 | dccp_insert_feat_opt(skb, opt->dccpop_type, | |
522 | opt->dccpop_feat, opt->dccpop_val, | |
523 | opt->dccpop_len); | |
524 | change++; | |
525 | } | |
526 | } | |
527 | ||
528 | /* Retransmit timer. | |
529 | * If this is the master listening sock, we don't set a timer on it. It | |
530 | * should be fine because if the dude doesn't receive our RESPONSE | |
531 | * [which will contain the CHANGE] he will send another REQUEST which | |
532 | * will "retrnasmit" the change. | |
533 | */ | |
534 | if (change && dp->dccps_role != DCCP_ROLE_LISTEN) { | |
535 | dccp_pr_debug("reset feat negotiation timer %p\n", sk); | |
536 | ||
537 | /* XXX don't reset the timer on re-transmissions. I.e. reset it | |
538 | * only when sending new stuff i guess. Currently the timer | |
539 | * never backs off because on re-transmission it just resets it! | |
540 | */ | |
541 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, | |
542 | inet_csk(sk)->icsk_rto, DCCP_RTO_MAX); | |
543 | } | |
2d0817d1 ACM |
544 | |
545 | return 0; | |
afe00251 AB |
546 | } |
547 | ||
af3b867e GR |
548 | /* The length of all options needs to be a multiple of 4 (5.8) */ |
549 | static void dccp_insert_option_padding(struct sk_buff *skb) | |
550 | { | |
551 | int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; | |
552 | ||
553 | if (padding != 0) { | |
554 | padding = 4 - padding; | |
555 | memset(skb_push(skb, padding), 0, padding); | |
556 | DCCP_SKB_CB(skb)->dccpd_opt_len += padding; | |
557 | } | |
558 | } | |
559 | ||
2d0817d1 | 560 | int dccp_insert_options(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
561 | { |
562 | struct dccp_sock *dp = dccp_sk(sk); | |
a4bf3902 | 563 | struct dccp_minisock *dmsk = dccp_msk(sk); |
7c657876 ACM |
564 | |
565 | DCCP_SKB_CB(skb)->dccpd_opt_len = 0; | |
566 | ||
a4bf3902 | 567 | if (dmsk->dccpms_send_ndp_count && |
2d0817d1 ACM |
568 | dccp_insert_option_ndp(sk, skb)) |
569 | return -1; | |
7c657876 ACM |
570 | |
571 | if (!dccp_packet_without_ack(skb)) { | |
a4bf3902 | 572 | if (dmsk->dccpms_send_ack_vector && |
2d0817d1 ACM |
573 | dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) && |
574 | dccp_insert_option_ackvec(sk, skb)) | |
575 | return -1; | |
7c657876 ACM |
576 | } |
577 | ||
507d37cf | 578 | if (dp->dccps_hc_rx_insert_options) { |
2d0817d1 ACM |
579 | if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb)) |
580 | return -1; | |
507d37cf ACM |
581 | dp->dccps_hc_rx_insert_options = 0; |
582 | } | |
7c657876 | 583 | |
afe00251 | 584 | /* Feature negotiation */ |
2d0817d1 ACM |
585 | /* Data packets can't do feat negotiation */ |
586 | if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA && | |
587 | DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK && | |
588 | dccp_insert_options_feat(sk, skb)) | |
589 | return -1; | |
afe00251 | 590 | |
89560b53 GR |
591 | /* |
592 | * Obtain RTT sample from Request/Response exchange. | |
593 | * This is currently used in CCID 3 initialisation. | |
594 | */ | |
595 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST && | |
596 | dccp_insert_option_timestamp(sk, skb)) | |
597 | return -1; | |
598 | ||
b4d4f7c7 GR |
599 | if (dp->dccps_timestamp_echo != 0 && |
600 | dccp_insert_option_timestamp_echo(dp, NULL, skb)) | |
601 | return -1; | |
602 | ||
af3b867e GR |
603 | dccp_insert_option_padding(skb); |
604 | return 0; | |
605 | } | |
7c657876 | 606 | |
af3b867e GR |
607 | int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) |
608 | { | |
609 | DCCP_SKB_CB(skb)->dccpd_opt_len = 0; | |
7c657876 | 610 | |
af3b867e GR |
611 | if (dreq->dreq_timestamp_echo != 0 && |
612 | dccp_insert_option_timestamp_echo(NULL, dreq, skb)) | |
613 | return -1; | |
2d0817d1 | 614 | |
af3b867e | 615 | dccp_insert_option_padding(skb); |
2d0817d1 | 616 | return 0; |
7c657876 | 617 | } |