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 | |
410e27a4 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; | |
410e27a4 GR |
29 | int sysctl_dccp_feat_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR; |
30 | int sysctl_dccp_feat_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT; | |
31 | ||
32 | static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len) | |
7c657876 | 33 | { |
410e27a4 | 34 | u32 value = 0; |
7c657876 ACM |
35 | |
36 | if (len > 3) | |
410e27a4 | 37 | value += *bf++ << 24; |
7c657876 | 38 | if (len > 2) |
410e27a4 | 39 | value += *bf++ << 16; |
7c657876 | 40 | if (len > 1) |
410e27a4 | 41 | value += *bf++ << 8; |
7c657876 ACM |
42 | if (len > 0) |
43 | value += *bf; | |
44 | ||
45 | return value; | |
46 | } | |
47 | ||
8b819412 GR |
48 | /** |
49 | * dccp_parse_options - Parse DCCP options present in @skb | |
50 | * @sk: client|server|listening dccp socket (when @dreq != NULL) | |
51 | * @dreq: request socket to use during connection setup, or NULL | |
52 | */ | |
53 | int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, | |
54 | struct sk_buff *skb) | |
7c657876 ACM |
55 | { |
56 | struct dccp_sock *dp = dccp_sk(sk); | |
7c657876 ACM |
57 | const struct dccp_hdr *dh = dccp_hdr(skb); |
58 | const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type; | |
410e27a4 | 59 | u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; |
7c657876 ACM |
60 | unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb); |
61 | unsigned char *opt_ptr = options; | |
7690af3f ACM |
62 | const unsigned char *opt_end = (unsigned char *)dh + |
63 | (dh->dccph_doff * 4); | |
7c657876 ACM |
64 | struct dccp_options_received *opt_recv = &dp->dccps_options_received; |
65 | unsigned char opt, len; | |
66 | unsigned char *value; | |
1c14ac0a | 67 | u32 elapsed_time; |
76fd1e87 | 68 | __be32 opt_val; |
afe00251 AB |
69 | int rc; |
70 | int mandatory = 0; | |
7c657876 ACM |
71 | |
72 | memset(opt_recv, 0, sizeof(*opt_recv)); | |
73 | ||
fb950496 | 74 | opt = len = 0; |
7c657876 ACM |
75 | while (opt_ptr != opt_end) { |
76 | opt = *opt_ptr++; | |
77 | len = 0; | |
78 | value = NULL; | |
79 | ||
80 | /* Check if this isn't a single byte option */ | |
81 | if (opt > DCCPO_MAX_RESERVED) { | |
82 | if (opt_ptr == opt_end) | |
faf61c33 | 83 | goto out_nonsensical_length; |
7c657876 ACM |
84 | |
85 | len = *opt_ptr++; | |
faf61c33 GR |
86 | if (len < 2) |
87 | goto out_nonsensical_length; | |
7c657876 ACM |
88 | /* |
89 | * Remove the type and len fields, leaving | |
90 | * just the value size | |
91 | */ | |
92 | len -= 2; | |
93 | value = opt_ptr; | |
94 | opt_ptr += len; | |
95 | ||
96 | if (opt_ptr > opt_end) | |
faf61c33 | 97 | goto out_nonsensical_length; |
7c657876 ACM |
98 | } |
99 | ||
8b819412 | 100 | /* |
410e27a4 GR |
101 | * CCID-Specific Options (from RFC 4340, sec. 10.3): |
102 | * | |
103 | * Option numbers 128 through 191 are for options sent from the | |
104 | * HC-Sender to the HC-Receiver; option numbers 192 through 255 | |
105 | * are for options sent from the HC-Receiver to the HC-Sender. | |
106 | * | |
8b819412 GR |
107 | * CCID-specific options are ignored during connection setup, as |
108 | * negotiation may still be in progress (see RFC 4340, 10.3). | |
65907a43 | 109 | * The same applies to Ack Vectors, as these depend on the CCID. |
410e27a4 | 110 | * |
8b819412 | 111 | */ |
410e27a4 | 112 | if (dreq != NULL && (opt >= 128 || |
65907a43 | 113 | opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1)) |
8b819412 GR |
114 | goto ignore_option; |
115 | ||
7c657876 ACM |
116 | switch (opt) { |
117 | case DCCPO_PADDING: | |
118 | break; | |
afe00251 AB |
119 | case DCCPO_MANDATORY: |
120 | if (mandatory) | |
121 | goto out_invalid_option; | |
6df9424a ACM |
122 | if (pkt_type != DCCP_PKT_DATA) |
123 | mandatory = 1; | |
afe00251 | 124 | break; |
7c657876 | 125 | case DCCPO_NDP_COUNT: |
5b5d0e70 | 126 | if (len > 6) |
7c657876 ACM |
127 | goto out_invalid_option; |
128 | ||
129 | opt_recv->dccpor_ndp = dccp_decode_value_var(value, len); | |
5b5d0e70 GR |
130 | dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk), |
131 | (unsigned long long)opt_recv->dccpor_ndp); | |
7c657876 | 132 | break; |
410e27a4 GR |
133 | case DCCPO_CHANGE_L: |
134 | /* fall through */ | |
135 | case DCCPO_CHANGE_R: | |
136 | if (pkt_type == DCCP_PKT_DATA) | |
cf86314c | 137 | break; |
410e27a4 GR |
138 | if (len < 2) |
139 | goto out_invalid_option; | |
140 | rc = dccp_feat_change_recv(sk, opt, *value, value + 1, | |
141 | len - 1); | |
142 | /* | |
143 | * When there is a change error, change_recv is | |
144 | * responsible for dealing with it. i.e. reply with an | |
145 | * empty confirm. | |
146 | * If the change was mandatory, then we need to die. | |
147 | */ | |
148 | if (rc && mandatory) | |
149 | goto out_invalid_option; | |
150 | break; | |
151 | case DCCPO_CONFIRM_L: | |
152 | /* fall through */ | |
153 | case DCCPO_CONFIRM_R: | |
154 | if (pkt_type == DCCP_PKT_DATA) | |
155 | break; | |
156 | if (len < 2) /* FIXME this disallows empty confirm */ | |
157 | goto out_invalid_option; | |
158 | if (dccp_feat_confirm_recv(sk, opt, *value, | |
159 | value + 1, len - 1)) | |
160 | goto out_invalid_option; | |
161 | break; | |
162 | case DCCPO_ACK_VECTOR_0: | |
163 | case DCCPO_ACK_VECTOR_1: | |
164 | if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ | |
165 | break; | |
166 | ||
167 | if (dccp_msk(sk)->dccpms_send_ack_vector && | |
168 | dccp_ackvec_parse(sk, skb, &ackno, opt, value, len)) | |
169 | goto out_invalid_option; | |
afe00251 | 170 | break; |
7c657876 ACM |
171 | case DCCPO_TIMESTAMP: |
172 | if (len != 4) | |
173 | goto out_invalid_option; | |
b4d4f7c7 GR |
174 | /* |
175 | * RFC 4340 13.1: "The precise time corresponding to | |
176 | * Timestamp Value zero is not specified". We use | |
177 | * zero to indicate absence of a meaningful timestamp. | |
178 | */ | |
76fd1e87 | 179 | opt_val = get_unaligned((__be32 *)value); |
b4d4f7c7 GR |
180 | if (unlikely(opt_val == 0)) { |
181 | DCCP_WARN("Timestamp with zero value\n"); | |
182 | break; | |
183 | } | |
7c657876 | 184 | |
b4d4f7c7 GR |
185 | if (dreq != NULL) { |
186 | dreq->dreq_timestamp_echo = ntohl(opt_val); | |
187 | dreq->dreq_timestamp_time = dccp_timestamp(); | |
188 | } else { | |
189 | opt_recv->dccpor_timestamp = | |
190 | dp->dccps_timestamp_echo = ntohl(opt_val); | |
191 | dp->dccps_timestamp_time = dccp_timestamp(); | |
192 | } | |
09dbc389 | 193 | dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", |
b4d4f7c7 | 194 | dccp_role(sk), ntohl(opt_val), |
f6ccf554 | 195 | (unsigned long long) |
7c657876 ACM |
196 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
197 | break; | |
198 | case DCCPO_TIMESTAMP_ECHO: | |
1bc09869 | 199 | if (len != 4 && len != 6 && len != 8) |
7c657876 ACM |
200 | goto out_invalid_option; |
201 | ||
76fd1e87 GR |
202 | opt_val = get_unaligned((__be32 *)value); |
203 | opt_recv->dccpor_timestamp_echo = ntohl(opt_val); | |
7c657876 | 204 | |
09dbc389 | 205 | dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, " |
f73f7097 | 206 | "ackno=%llu", dccp_role(sk), |
7690af3f | 207 | opt_recv->dccpor_timestamp_echo, |
f6ccf554 DM |
208 | len + 2, |
209 | (unsigned long long) | |
1bc09869 IM |
210 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
211 | ||
76fd1e87 | 212 | value += 4; |
1bc09869 | 213 | |
76fd1e87 | 214 | if (len == 4) { /* no elapsed time included */ |
f73f7097 | 215 | dccp_pr_debug_cat("\n"); |
1c14ac0a | 216 | break; |
f73f7097 | 217 | } |
1c14ac0a | 218 | |
76fd1e87 GR |
219 | if (len == 6) { /* 2-byte elapsed time */ |
220 | __be16 opt_val2 = get_unaligned((__be16 *)value); | |
221 | elapsed_time = ntohs(opt_val2); | |
222 | } else { /* 4-byte elapsed time */ | |
223 | opt_val = get_unaligned((__be32 *)value); | |
224 | elapsed_time = ntohl(opt_val); | |
225 | } | |
1c14ac0a | 226 | |
dcad856f | 227 | dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time); |
f73f7097 | 228 | |
1c14ac0a ACM |
229 | /* Give precedence to the biggest ELAPSED_TIME */ |
230 | if (elapsed_time > opt_recv->dccpor_elapsed_time) | |
231 | opt_recv->dccpor_elapsed_time = elapsed_time; | |
7c657876 ACM |
232 | break; |
233 | case DCCPO_ELAPSED_TIME: | |
c86ab2b6 GR |
234 | if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ |
235 | break; | |
1bc09869 | 236 | |
76fd1e87 GR |
237 | if (len == 2) { |
238 | __be16 opt_val2 = get_unaligned((__be16 *)value); | |
239 | elapsed_time = ntohs(opt_val2); | |
c86ab2b6 | 240 | } else if (len == 4) { |
76fd1e87 GR |
241 | opt_val = get_unaligned((__be32 *)value); |
242 | elapsed_time = ntohl(opt_val); | |
c86ab2b6 GR |
243 | } else { |
244 | goto out_invalid_option; | |
76fd1e87 | 245 | } |
1c14ac0a ACM |
246 | |
247 | if (elapsed_time > opt_recv->dccpor_elapsed_time) | |
248 | opt_recv->dccpor_elapsed_time = elapsed_time; | |
1bc09869 | 249 | |
09dbc389 GR |
250 | dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", |
251 | dccp_role(sk), elapsed_time); | |
7c657876 | 252 | break; |
410e27a4 GR |
253 | case 128 ... 191: { |
254 | const u16 idx = value - options; | |
255 | ||
7690af3f | 256 | if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk, |
410e27a4 GR |
257 | opt, len, idx, |
258 | value) != 0) | |
7c657876 | 259 | goto out_invalid_option; |
410e27a4 | 260 | } |
7c657876 | 261 | break; |
410e27a4 GR |
262 | case 192 ... 255: { |
263 | const u16 idx = value - options; | |
264 | ||
7690af3f | 265 | if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk, |
410e27a4 GR |
266 | opt, len, idx, |
267 | value) != 0) | |
7c657876 | 268 | goto out_invalid_option; |
410e27a4 | 269 | } |
7c657876 ACM |
270 | break; |
271 | default: | |
59348b19 GR |
272 | DCCP_CRIT("DCCP(%p): option %d(len=%d) not " |
273 | "implemented, ignoring", sk, opt, len); | |
7c657876 | 274 | break; |
c9eaf173 | 275 | } |
8b819412 | 276 | ignore_option: |
afe00251 AB |
277 | if (opt != DCCPO_MANDATORY) |
278 | mandatory = 0; | |
7c657876 ACM |
279 | } |
280 | ||
6df9424a ACM |
281 | /* mandatory was the last byte in option list -> reset connection */ |
282 | if (mandatory) | |
283 | goto out_invalid_option; | |
284 | ||
faf61c33 GR |
285 | out_nonsensical_length: |
286 | /* RFC 4340, 5.8: ignore option and all remaining option space */ | |
7c657876 ACM |
287 | return 0; |
288 | ||
289 | out_invalid_option: | |
290 | DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT); | |
410e27a4 GR |
291 | DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR; |
292 | DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len); | |
eac7726b GR |
293 | DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt; |
294 | DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0; | |
295 | DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0; | |
7c657876 ACM |
296 | return -1; |
297 | } | |
298 | ||
b61fafc4 ACM |
299 | EXPORT_SYMBOL_GPL(dccp_parse_options); |
300 | ||
410e27a4 GR |
301 | static void dccp_encode_value_var(const u32 value, unsigned char *to, |
302 | const unsigned int len) | |
7c657876 ACM |
303 | { |
304 | if (len > 3) | |
305 | *to++ = (value & 0xFF000000) >> 24; | |
306 | if (len > 2) | |
307 | *to++ = (value & 0xFF0000) >> 16; | |
308 | if (len > 1) | |
309 | *to++ = (value & 0xFF00) >> 8; | |
310 | if (len > 0) | |
311 | *to++ = (value & 0xFF); | |
312 | } | |
313 | ||
5b5d0e70 | 314 | static inline u8 dccp_ndp_len(const u64 ndp) |
7c657876 | 315 | { |
5b5d0e70 GR |
316 | if (likely(ndp <= 0xFF)) |
317 | return 1; | |
318 | return likely(ndp <= USHORT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6); | |
7c657876 ACM |
319 | } |
320 | ||
2d0817d1 | 321 | int dccp_insert_option(struct sock *sk, struct sk_buff *skb, |
7c657876 ACM |
322 | const unsigned char option, |
323 | const void *value, const unsigned char len) | |
324 | { | |
325 | unsigned char *to; | |
326 | ||
2d0817d1 ACM |
327 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) |
328 | return -1; | |
7c657876 ACM |
329 | |
330 | DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2; | |
331 | ||
332 | to = skb_push(skb, len + 2); | |
333 | *to++ = option; | |
334 | *to++ = len + 2; | |
335 | ||
336 | memcpy(to, value, len); | |
2d0817d1 | 337 | return 0; |
7c657876 ACM |
338 | } |
339 | ||
340 | EXPORT_SYMBOL_GPL(dccp_insert_option); | |
341 | ||
2d0817d1 | 342 | static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
343 | { |
344 | struct dccp_sock *dp = dccp_sk(sk); | |
5b5d0e70 | 345 | u64 ndp = dp->dccps_ndp_count; |
7c657876 ACM |
346 | |
347 | if (dccp_non_data_packet(skb)) | |
348 | ++dp->dccps_ndp_count; | |
349 | else | |
350 | dp->dccps_ndp_count = 0; | |
351 | ||
352 | if (ndp > 0) { | |
353 | unsigned char *ptr; | |
354 | const int ndp_len = dccp_ndp_len(ndp); | |
355 | const int len = ndp_len + 2; | |
356 | ||
357 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) | |
2d0817d1 | 358 | return -1; |
7c657876 ACM |
359 | |
360 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
361 | ||
362 | ptr = skb_push(skb, len); | |
363 | *ptr++ = DCCPO_NDP_COUNT; | |
364 | *ptr++ = len; | |
365 | dccp_encode_value_var(ndp, ptr, ndp_len); | |
366 | } | |
2d0817d1 ACM |
367 | |
368 | return 0; | |
7c657876 ACM |
369 | } |
370 | ||
371 | static inline int dccp_elapsed_time_len(const u32 elapsed_time) | |
372 | { | |
b1c9fe7b | 373 | return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; |
7c657876 ACM |
374 | } |
375 | ||
2d0817d1 ACM |
376 | int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb, |
377 | u32 elapsed_time) | |
7c657876 | 378 | { |
7c657876 ACM |
379 | const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); |
380 | const int len = 2 + elapsed_time_len; | |
381 | unsigned char *to; | |
382 | ||
1bc09869 | 383 | if (elapsed_time_len == 0) |
2d0817d1 | 384 | return 0; |
7c657876 | 385 | |
2d0817d1 ACM |
386 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) |
387 | return -1; | |
7c657876 ACM |
388 | |
389 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
390 | ||
391 | to = skb_push(skb, len); | |
392 | *to++ = DCCPO_ELAPSED_TIME; | |
393 | *to++ = len; | |
394 | ||
1bc09869 | 395 | if (elapsed_time_len == 2) { |
60fe62e7 | 396 | const __be16 var16 = htons((u16)elapsed_time); |
1bc09869 IM |
397 | memcpy(to, &var16, 2); |
398 | } else { | |
60fe62e7 | 399 | const __be32 var32 = htonl(elapsed_time); |
1bc09869 IM |
400 | memcpy(to, &var32, 4); |
401 | } | |
7c657876 | 402 | |
2d0817d1 | 403 | return 0; |
7c657876 ACM |
404 | } |
405 | ||
d4b81ff7 | 406 | EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); |
7c657876 | 407 | |
2d0817d1 | 408 | int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb) |
7c657876 | 409 | { |
4c70f383 | 410 | __be32 now = htonl(dccp_timestamp()); |
1bc09869 IM |
411 | /* yes this will overflow but that is the point as we want a |
412 | * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ | |
413 | ||
2d0817d1 | 414 | return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now)); |
7c657876 ACM |
415 | } |
416 | ||
d4b81ff7 ACM |
417 | EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp); |
418 | ||
b4d4f7c7 GR |
419 | static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, |
420 | struct dccp_request_sock *dreq, | |
2d0817d1 | 421 | struct sk_buff *skb) |
7c657876 | 422 | { |
60fe62e7 | 423 | __be32 tstamp_echo; |
7c657876 | 424 | unsigned char *to; |
b4d4f7c7 GR |
425 | u32 elapsed_time, elapsed_time_len, len; |
426 | ||
427 | if (dreq != NULL) { | |
428 | elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; | |
429 | tstamp_echo = htonl(dreq->dreq_timestamp_echo); | |
430 | dreq->dreq_timestamp_echo = 0; | |
431 | } else { | |
432 | elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; | |
433 | tstamp_echo = htonl(dp->dccps_timestamp_echo); | |
434 | dp->dccps_timestamp_echo = 0; | |
435 | } | |
436 | ||
b0e56780 ACM |
437 | elapsed_time_len = dccp_elapsed_time_len(elapsed_time); |
438 | len = 6 + elapsed_time_len; | |
439 | ||
2d0817d1 ACM |
440 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) |
441 | return -1; | |
7c657876 ACM |
442 | |
443 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; | |
444 | ||
445 | to = skb_push(skb, len); | |
446 | *to++ = DCCPO_TIMESTAMP_ECHO; | |
447 | *to++ = len; | |
448 | ||
7c657876 ACM |
449 | memcpy(to, &tstamp_echo, 4); |
450 | to += 4; | |
afe00251 | 451 | |
1bc09869 | 452 | if (elapsed_time_len == 2) { |
60fe62e7 | 453 | const __be16 var16 = htons((u16)elapsed_time); |
1bc09869 IM |
454 | memcpy(to, &var16, 2); |
455 | } else if (elapsed_time_len == 4) { | |
60fe62e7 | 456 | const __be32 var32 = htonl(elapsed_time); |
1bc09869 IM |
457 | memcpy(to, &var32, 4); |
458 | } | |
7c657876 | 459 | |
2d0817d1 | 460 | return 0; |
7c657876 ACM |
461 | } |
462 | ||
410e27a4 GR |
463 | static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat, |
464 | u8 *val, u8 len) | |
4829007c | 465 | { |
410e27a4 | 466 | u8 *to; |
4829007c | 467 | |
410e27a4 GR |
468 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) { |
469 | DCCP_WARN("packet too small for feature %d option!\n", feat); | |
4829007c | 470 | return -1; |
c2f42077 | 471 | } |
4829007c | 472 | |
410e27a4 | 473 | DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3; |
4829007c | 474 | |
410e27a4 GR |
475 | to = skb_push(skb, len + 3); |
476 | *to++ = type; | |
477 | *to++ = len + 3; | |
478 | *to++ = feat; | |
4829007c | 479 | |
410e27a4 GR |
480 | if (len) |
481 | memcpy(to, val, len); | |
d0440ee6 | 482 | |
410e27a4 GR |
483 | dccp_pr_debug("%s(%s (%d), ...), length %d\n", |
484 | dccp_feat_typename(type), | |
485 | dccp_feat_name(feat), feat, len); | |
d0440ee6 GR |
486 | return 0; |
487 | } | |
488 | ||
410e27a4 | 489 | static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb) |
afe00251 | 490 | { |
410e27a4 GR |
491 | struct dccp_minisock *dmsk = dccp_msk(sk); |
492 | struct dccp_opt_pend *opt, *next; | |
493 | int change = 0; | |
494 | ||
495 | /* confirm any options [NN opts] */ | |
496 | list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) { | |
497 | dccp_insert_feat_opt(skb, opt->dccpop_type, | |
498 | opt->dccpop_feat, opt->dccpop_val, | |
499 | opt->dccpop_len); | |
500 | /* fear empty confirms */ | |
501 | if (opt->dccpop_val) | |
502 | kfree(opt->dccpop_val); | |
503 | kfree(opt); | |
504 | } | |
505 | INIT_LIST_HEAD(&dmsk->dccpms_conf); | |
506 | ||
507 | /* see which features we need to send */ | |
508 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { | |
509 | /* see if we need to send any confirm */ | |
510 | if (opt->dccpop_sc) { | |
511 | dccp_insert_feat_opt(skb, opt->dccpop_type + 1, | |
512 | opt->dccpop_feat, | |
513 | opt->dccpop_sc->dccpoc_val, | |
514 | opt->dccpop_sc->dccpoc_len); | |
515 | ||
516 | BUG_ON(!opt->dccpop_sc->dccpoc_val); | |
517 | kfree(opt->dccpop_sc->dccpoc_val); | |
518 | kfree(opt->dccpop_sc); | |
519 | opt->dccpop_sc = NULL; | |
520 | } | |
afe00251 | 521 | |
410e27a4 GR |
522 | /* any option not confirmed, re-send it */ |
523 | if (!opt->dccpop_conf) { | |
524 | dccp_insert_feat_opt(skb, opt->dccpop_type, | |
525 | opt->dccpop_feat, opt->dccpop_val, | |
526 | opt->dccpop_len); | |
527 | change++; | |
528 | } | |
afe00251 AB |
529 | } |
530 | ||
afe00251 AB |
531 | return 0; |
532 | } | |
533 | ||
af3b867e GR |
534 | /* The length of all options needs to be a multiple of 4 (5.8) */ |
535 | static void dccp_insert_option_padding(struct sk_buff *skb) | |
536 | { | |
537 | int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; | |
538 | ||
539 | if (padding != 0) { | |
540 | padding = 4 - padding; | |
541 | memset(skb_push(skb, padding), 0, padding); | |
542 | DCCP_SKB_CB(skb)->dccpd_opt_len += padding; | |
543 | } | |
544 | } | |
545 | ||
2d0817d1 | 546 | int dccp_insert_options(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
547 | { |
548 | struct dccp_sock *dp = dccp_sk(sk); | |
410e27a4 | 549 | struct dccp_minisock *dmsk = dccp_msk(sk); |
7c657876 ACM |
550 | |
551 | DCCP_SKB_CB(skb)->dccpd_opt_len = 0; | |
552 | ||
410e27a4 GR |
553 | if (dmsk->dccpms_send_ndp_count && |
554 | dccp_insert_option_ndp(sk, skb)) | |
2d0817d1 | 555 | return -1; |
7c657876 | 556 | |
410e27a4 GR |
557 | if (!dccp_packet_without_ack(skb)) { |
558 | if (dmsk->dccpms_send_ack_vector && | |
559 | dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) && | |
560 | dccp_insert_option_ackvec(sk, skb)) | |
2d0817d1 | 561 | return -1; |
7c657876 ACM |
562 | } |
563 | ||
507d37cf | 564 | if (dp->dccps_hc_rx_insert_options) { |
2d0817d1 ACM |
565 | if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb)) |
566 | return -1; | |
507d37cf ACM |
567 | dp->dccps_hc_rx_insert_options = 0; |
568 | } | |
7c657876 | 569 | |
410e27a4 GR |
570 | /* Feature negotiation */ |
571 | /* Data packets can't do feat negotiation */ | |
572 | if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA && | |
573 | DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK && | |
574 | dccp_insert_options_feat(sk, skb)) | |
575 | return -1; | |
576 | ||
577 | /* | |
578 | * Obtain RTT sample from Request/Response exchange. | |
579 | * This is currently used in CCID 3 initialisation. | |
580 | */ | |
581 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST && | |
582 | dccp_insert_option_timestamp(sk, skb)) | |
583 | return -1; | |
584 | ||
b4d4f7c7 GR |
585 | if (dp->dccps_timestamp_echo != 0 && |
586 | dccp_insert_option_timestamp_echo(dp, NULL, skb)) | |
587 | return -1; | |
588 | ||
af3b867e GR |
589 | dccp_insert_option_padding(skb); |
590 | return 0; | |
591 | } | |
7c657876 | 592 | |
af3b867e GR |
593 | int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) |
594 | { | |
595 | DCCP_SKB_CB(skb)->dccpd_opt_len = 0; | |
7c657876 | 596 | |
af3b867e GR |
597 | if (dreq->dreq_timestamp_echo != 0 && |
598 | dccp_insert_option_timestamp_echo(NULL, dreq, skb)) | |
599 | return -1; | |
2d0817d1 | 600 | |
af3b867e | 601 | dccp_insert_option_padding(skb); |
2d0817d1 | 602 | return 0; |
7c657876 | 603 | } |