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Commit | Line | Data |
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afe00251 AB |
1 | /* |
2 | * net/dccp/feat.c | |
3 | * | |
4 | * An implementation of the DCCP protocol | |
5 | * Andrea Bittau <a.bittau@cs.ucl.ac.uk> | |
6 | * | |
5cdae198 GR |
7 | * ASSUMPTIONS |
8 | * ----------- | |
f74e91b6 GR |
9 | * o Feature negotiation is coordinated with connection setup (as in TCP), wild |
10 | * changes of parameters of an established connection are not supported. | |
5cdae198 GR |
11 | * o All currently known SP features have 1-byte quantities. If in the future |
12 | * extensions of RFCs 4340..42 define features with item lengths larger than | |
13 | * one byte, a feature-specific extension of the code will be required. | |
14 | * | |
15 | * This program is free software; you can redistribute it and/or | |
16 | * modify it under the terms of the GNU General Public License | |
17 | * as published by the Free Software Foundation; either version | |
18 | * 2 of the License, or (at your option) any later version. | |
afe00251 AB |
19 | */ |
20 | ||
afe00251 AB |
21 | #include <linux/module.h> |
22 | ||
6ffd30fb | 23 | #include "ccid.h" |
afe00251 AB |
24 | #include "feat.h" |
25 | ||
26 | #define DCCP_FEAT_SP_NOAGREE (-123) | |
27 | ||
7d43d1a0 GR |
28 | static const struct { |
29 | u8 feat_num; /* DCCPF_xxx */ | |
30 | enum dccp_feat_type rxtx; /* RX or TX */ | |
31 | enum dccp_feat_type reconciliation; /* SP or NN */ | |
32 | u8 default_value; /* as in 6.4 */ | |
33 | /* | |
34 | * Lookup table for location and type of features (from RFC 4340/4342) | |
35 | * +--------------------------+----+-----+----+----+---------+-----------+ | |
36 | * | Feature | Location | Reconc. | Initial | Section | | |
37 | * | | RX | TX | SP | NN | Value | Reference | | |
38 | * +--------------------------+----+-----+----+----+---------+-----------+ | |
39 | * | DCCPF_CCID | | X | X | | 2 | 10 | | |
40 | * | DCCPF_SHORT_SEQNOS | | X | X | | 0 | 7.6.1 | | |
41 | * | DCCPF_SEQUENCE_WINDOW | | X | | X | 100 | 7.5.2 | | |
42 | * | DCCPF_ECN_INCAPABLE | X | | X | | 0 | 12.1 | | |
43 | * | DCCPF_ACK_RATIO | | X | | X | 2 | 11.3 | | |
44 | * | DCCPF_SEND_ACK_VECTOR | X | | X | | 0 | 11.5 | | |
45 | * | DCCPF_SEND_NDP_COUNT | | X | X | | 0 | 7.7.2 | | |
46 | * | DCCPF_MIN_CSUM_COVER | X | | X | | 0 | 9.2.1 | | |
47 | * | DCCPF_DATA_CHECKSUM | X | | X | | 0 | 9.3.1 | | |
48 | * | DCCPF_SEND_LEV_RATE | X | | X | | 0 | 4342/8.4 | | |
49 | * +--------------------------+----+-----+----+----+---------+-----------+ | |
50 | */ | |
51 | } dccp_feat_table[] = { | |
52 | { DCCPF_CCID, FEAT_AT_TX, FEAT_SP, 2 }, | |
53 | { DCCPF_SHORT_SEQNOS, FEAT_AT_TX, FEAT_SP, 0 }, | |
54 | { DCCPF_SEQUENCE_WINDOW, FEAT_AT_TX, FEAT_NN, 100 }, | |
55 | { DCCPF_ECN_INCAPABLE, FEAT_AT_RX, FEAT_SP, 0 }, | |
56 | { DCCPF_ACK_RATIO, FEAT_AT_TX, FEAT_NN, 2 }, | |
57 | { DCCPF_SEND_ACK_VECTOR, FEAT_AT_RX, FEAT_SP, 0 }, | |
58 | { DCCPF_SEND_NDP_COUNT, FEAT_AT_TX, FEAT_SP, 0 }, | |
59 | { DCCPF_MIN_CSUM_COVER, FEAT_AT_RX, FEAT_SP, 0 }, | |
60 | { DCCPF_DATA_CHECKSUM, FEAT_AT_RX, FEAT_SP, 0 }, | |
61 | { DCCPF_SEND_LEV_RATE, FEAT_AT_RX, FEAT_SP, 0 }, | |
62 | }; | |
63 | #define DCCP_FEAT_SUPPORTED_MAX ARRAY_SIZE(dccp_feat_table) | |
64 | ||
61e6473e GR |
65 | /** |
66 | * dccp_feat_index - Hash function to map feature number into array position | |
67 | * Returns consecutive array index or -1 if the feature is not understood. | |
68 | */ | |
69 | static int dccp_feat_index(u8 feat_num) | |
70 | { | |
71 | /* The first 9 entries are occupied by the types from RFC 4340, 6.4 */ | |
72 | if (feat_num > DCCPF_RESERVED && feat_num <= DCCPF_DATA_CHECKSUM) | |
73 | return feat_num - 1; | |
74 | ||
75 | /* | |
76 | * Other features: add cases for new feature types here after adding | |
77 | * them to the above table. | |
78 | */ | |
79 | switch (feat_num) { | |
80 | case DCCPF_SEND_LEV_RATE: | |
81 | return DCCP_FEAT_SUPPORTED_MAX - 1; | |
82 | } | |
83 | return -1; | |
84 | } | |
85 | ||
86 | static u8 dccp_feat_type(u8 feat_num) | |
87 | { | |
88 | int idx = dccp_feat_index(feat_num); | |
89 | ||
90 | if (idx < 0) | |
91 | return FEAT_UNKNOWN; | |
92 | return dccp_feat_table[idx].reconciliation; | |
93 | } | |
94 | ||
ac75773c GR |
95 | /* copy constructor, fval must not already contain allocated memory */ |
96 | static int dccp_feat_clone_sp_val(dccp_feat_val *fval, u8 const *val, u8 len) | |
97 | { | |
98 | fval->sp.len = len; | |
99 | if (fval->sp.len > 0) { | |
100 | fval->sp.vec = kmemdup(val, len, gfp_any()); | |
101 | if (fval->sp.vec == NULL) { | |
102 | fval->sp.len = 0; | |
103 | return -ENOBUFS; | |
104 | } | |
105 | } | |
106 | return 0; | |
107 | } | |
108 | ||
61e6473e GR |
109 | static void dccp_feat_val_destructor(u8 feat_num, dccp_feat_val *val) |
110 | { | |
111 | if (unlikely(val == NULL)) | |
112 | return; | |
113 | if (dccp_feat_type(feat_num) == FEAT_SP) | |
114 | kfree(val->sp.vec); | |
115 | memset(val, 0, sizeof(*val)); | |
116 | } | |
117 | ||
ac75773c GR |
118 | static struct dccp_feat_entry * |
119 | dccp_feat_clone_entry(struct dccp_feat_entry const *original) | |
120 | { | |
121 | struct dccp_feat_entry *new; | |
122 | u8 type = dccp_feat_type(original->feat_num); | |
123 | ||
124 | if (type == FEAT_UNKNOWN) | |
125 | return NULL; | |
126 | ||
127 | new = kmemdup(original, sizeof(struct dccp_feat_entry), gfp_any()); | |
128 | if (new == NULL) | |
129 | return NULL; | |
130 | ||
131 | if (type == FEAT_SP && dccp_feat_clone_sp_val(&new->val, | |
132 | original->val.sp.vec, | |
133 | original->val.sp.len)) { | |
134 | kfree(new); | |
135 | return NULL; | |
136 | } | |
137 | return new; | |
138 | } | |
139 | ||
61e6473e GR |
140 | static void dccp_feat_entry_destructor(struct dccp_feat_entry *entry) |
141 | { | |
142 | if (entry != NULL) { | |
143 | dccp_feat_val_destructor(entry->feat_num, &entry->val); | |
144 | kfree(entry); | |
145 | } | |
146 | } | |
147 | ||
148 | /* | |
149 | * List management functions | |
150 | * | |
151 | * Feature negotiation lists rely on and maintain the following invariants: | |
152 | * - each feat_num in the list is known, i.e. we know its type and default value | |
153 | * - each feat_num/is_local combination is unique (old entries are overwritten) | |
154 | * - SP values are always freshly allocated | |
155 | * - list is sorted in increasing order of feature number (faster lookup) | |
156 | */ | |
157 | ||
158 | static inline void dccp_feat_list_pop(struct dccp_feat_entry *entry) | |
159 | { | |
160 | list_del(&entry->node); | |
161 | dccp_feat_entry_destructor(entry); | |
162 | } | |
163 | ||
164 | void dccp_feat_list_purge(struct list_head *fn_list) | |
165 | { | |
166 | struct dccp_feat_entry *entry, *next; | |
167 | ||
168 | list_for_each_entry_safe(entry, next, fn_list, node) | |
169 | dccp_feat_entry_destructor(entry); | |
170 | INIT_LIST_HEAD(fn_list); | |
171 | } | |
172 | EXPORT_SYMBOL_GPL(dccp_feat_list_purge); | |
173 | ||
ac75773c GR |
174 | /* generate @to as full clone of @from - @to must not contain any nodes */ |
175 | int dccp_feat_clone_list(struct list_head const *from, struct list_head *to) | |
176 | { | |
177 | struct dccp_feat_entry *entry, *new; | |
178 | ||
179 | INIT_LIST_HEAD(to); | |
180 | list_for_each_entry(entry, from, node) { | |
181 | new = dccp_feat_clone_entry(entry); | |
182 | if (new == NULL) | |
183 | goto cloning_failed; | |
184 | list_add_tail(&new->node, to); | |
185 | } | |
186 | return 0; | |
187 | ||
188 | cloning_failed: | |
189 | dccp_feat_list_purge(to); | |
190 | return -ENOMEM; | |
191 | } | |
192 | ||
8ca0d17b ACM |
193 | int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature, |
194 | u8 *val, u8 len, gfp_t gfp) | |
afe00251 | 195 | { |
afe00251 AB |
196 | struct dccp_opt_pend *opt; |
197 | ||
c02fdc0e | 198 | dccp_feat_debug(type, feature, *val); |
afe00251 | 199 | |
dd6303df | 200 | if (len > 3) { |
59348b19 | 201 | DCCP_WARN("invalid length %d\n", len); |
19443178 | 202 | return -EINVAL; |
c02fdc0e GR |
203 | } |
204 | /* XXX add further sanity checks */ | |
6ffd30fb | 205 | |
afe00251 | 206 | /* check if that feature is already being negotiated */ |
a4bf3902 | 207 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
208 | /* ok we found a negotiation for this option already */ |
209 | if (opt->dccpop_feat == feature && opt->dccpop_type == type) { | |
210 | dccp_pr_debug("Replacing old\n"); | |
211 | /* replace */ | |
212 | BUG_ON(opt->dccpop_val == NULL); | |
213 | kfree(opt->dccpop_val); | |
214 | opt->dccpop_val = val; | |
215 | opt->dccpop_len = len; | |
216 | opt->dccpop_conf = 0; | |
217 | return 0; | |
218 | } | |
219 | } | |
220 | ||
221 | /* negotiation for a new feature */ | |
222 | opt = kmalloc(sizeof(*opt), gfp); | |
223 | if (opt == NULL) | |
224 | return -ENOMEM; | |
225 | ||
226 | opt->dccpop_type = type; | |
227 | opt->dccpop_feat = feature; | |
228 | opt->dccpop_len = len; | |
229 | opt->dccpop_val = val; | |
230 | opt->dccpop_conf = 0; | |
231 | opt->dccpop_sc = NULL; | |
232 | ||
233 | BUG_ON(opt->dccpop_val == NULL); | |
234 | ||
a4bf3902 | 235 | list_add_tail(&opt->dccpop_node, &dmsk->dccpms_pending); |
afe00251 AB |
236 | return 0; |
237 | } | |
238 | ||
239 | EXPORT_SYMBOL_GPL(dccp_feat_change); | |
240 | ||
6ffd30fb AB |
241 | static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr) |
242 | { | |
243 | struct dccp_sock *dp = dccp_sk(sk); | |
a4bf3902 | 244 | struct dccp_minisock *dmsk = dccp_msk(sk); |
6ffd30fb AB |
245 | /* figure out if we are changing our CCID or the peer's */ |
246 | const int rx = type == DCCPO_CHANGE_R; | |
a4bf3902 | 247 | const u8 ccid_nr = rx ? dmsk->dccpms_rx_ccid : dmsk->dccpms_tx_ccid; |
6ffd30fb AB |
248 | struct ccid *new_ccid; |
249 | ||
250 | /* Check if nothing is being changed. */ | |
251 | if (ccid_nr == new_ccid_nr) | |
252 | return 0; | |
253 | ||
254 | new_ccid = ccid_new(new_ccid_nr, sk, rx, GFP_ATOMIC); | |
255 | if (new_ccid == NULL) | |
256 | return -ENOMEM; | |
257 | ||
258 | if (rx) { | |
259 | ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); | |
260 | dp->dccps_hc_rx_ccid = new_ccid; | |
a4bf3902 | 261 | dmsk->dccpms_rx_ccid = new_ccid_nr; |
6ffd30fb AB |
262 | } else { |
263 | ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); | |
264 | dp->dccps_hc_tx_ccid = new_ccid; | |
a4bf3902 | 265 | dmsk->dccpms_tx_ccid = new_ccid_nr; |
6ffd30fb AB |
266 | } |
267 | ||
268 | return 0; | |
269 | } | |
270 | ||
afe00251 AB |
271 | static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val) |
272 | { | |
c02fdc0e | 273 | dccp_feat_debug(type, feat, val); |
6ffd30fb AB |
274 | |
275 | switch (feat) { | |
276 | case DCCPF_CCID: | |
277 | return dccp_feat_update_ccid(sk, type, val); | |
278 | default: | |
c02fdc0e GR |
279 | dccp_pr_debug("UNIMPLEMENTED: %s(%d, ...)\n", |
280 | dccp_feat_typename(type), feat); | |
6ffd30fb AB |
281 | break; |
282 | } | |
afe00251 AB |
283 | return 0; |
284 | } | |
285 | ||
286 | static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt, | |
287 | u8 *rpref, u8 rlen) | |
288 | { | |
289 | struct dccp_sock *dp = dccp_sk(sk); | |
290 | u8 *spref, slen, *res = NULL; | |
291 | int i, j, rc, agree = 1; | |
292 | ||
293 | BUG_ON(rpref == NULL); | |
294 | ||
295 | /* check if we are the black sheep */ | |
296 | if (dp->dccps_role == DCCP_ROLE_CLIENT) { | |
297 | spref = rpref; | |
298 | slen = rlen; | |
299 | rpref = opt->dccpop_val; | |
300 | rlen = opt->dccpop_len; | |
301 | } else { | |
302 | spref = opt->dccpop_val; | |
303 | slen = opt->dccpop_len; | |
304 | } | |
305 | /* | |
306 | * Now we have server preference list in spref and client preference in | |
307 | * rpref | |
308 | */ | |
309 | BUG_ON(spref == NULL); | |
310 | BUG_ON(rpref == NULL); | |
311 | ||
312 | /* FIXME sanity check vals */ | |
313 | ||
314 | /* Are values in any order? XXX Lame "algorithm" here */ | |
afe00251 AB |
315 | for (i = 0; i < slen; i++) { |
316 | for (j = 0; j < rlen; j++) { | |
317 | if (spref[i] == rpref[j]) { | |
318 | res = &spref[i]; | |
319 | break; | |
320 | } | |
321 | } | |
322 | if (res) | |
323 | break; | |
324 | } | |
325 | ||
326 | /* we didn't agree on anything */ | |
327 | if (res == NULL) { | |
328 | /* confirm previous value */ | |
329 | switch (opt->dccpop_feat) { | |
330 | case DCCPF_CCID: | |
331 | /* XXX did i get this right? =P */ | |
332 | if (opt->dccpop_type == DCCPO_CHANGE_L) | |
a4bf3902 | 333 | res = &dccp_msk(sk)->dccpms_tx_ccid; |
afe00251 | 334 | else |
a4bf3902 | 335 | res = &dccp_msk(sk)->dccpms_rx_ccid; |
afe00251 AB |
336 | break; |
337 | ||
338 | default: | |
59348b19 GR |
339 | DCCP_BUG("Fell through, feat=%d", opt->dccpop_feat); |
340 | /* XXX implement res */ | |
afe00251 AB |
341 | return -EFAULT; |
342 | } | |
343 | ||
344 | dccp_pr_debug("Don't agree... reconfirming %d\n", *res); | |
345 | agree = 0; /* this is used for mandatory options... */ | |
346 | } | |
347 | ||
348 | /* need to put result and our preference list */ | |
afe00251 AB |
349 | rlen = 1 + opt->dccpop_len; |
350 | rpref = kmalloc(rlen, GFP_ATOMIC); | |
351 | if (rpref == NULL) | |
352 | return -ENOMEM; | |
353 | ||
354 | *rpref = *res; | |
355 | memcpy(&rpref[1], opt->dccpop_val, opt->dccpop_len); | |
356 | ||
357 | /* put it in the "confirm queue" */ | |
358 | if (opt->dccpop_sc == NULL) { | |
359 | opt->dccpop_sc = kmalloc(sizeof(*opt->dccpop_sc), GFP_ATOMIC); | |
360 | if (opt->dccpop_sc == NULL) { | |
361 | kfree(rpref); | |
362 | return -ENOMEM; | |
363 | } | |
364 | } else { | |
365 | /* recycle the confirm slot */ | |
366 | BUG_ON(opt->dccpop_sc->dccpoc_val == NULL); | |
367 | kfree(opt->dccpop_sc->dccpoc_val); | |
368 | dccp_pr_debug("recycling confirm slot\n"); | |
369 | } | |
370 | memset(opt->dccpop_sc, 0, sizeof(*opt->dccpop_sc)); | |
371 | ||
372 | opt->dccpop_sc->dccpoc_val = rpref; | |
373 | opt->dccpop_sc->dccpoc_len = rlen; | |
374 | ||
375 | /* update the option on our side [we are about to send the confirm] */ | |
376 | rc = dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *res); | |
377 | if (rc) { | |
378 | kfree(opt->dccpop_sc->dccpoc_val); | |
379 | kfree(opt->dccpop_sc); | |
68907dad | 380 | opt->dccpop_sc = NULL; |
afe00251 AB |
381 | return rc; |
382 | } | |
383 | ||
384 | dccp_pr_debug("Will confirm %d\n", *rpref); | |
385 | ||
386 | /* say we want to change to X but we just got a confirm X, suppress our | |
387 | * change | |
388 | */ | |
389 | if (!opt->dccpop_conf) { | |
390 | if (*opt->dccpop_val == *res) | |
391 | opt->dccpop_conf = 1; | |
392 | dccp_pr_debug("won't ask for change of same feature\n"); | |
393 | } | |
394 | ||
395 | return agree ? 0 : DCCP_FEAT_SP_NOAGREE; /* used for mandatory opts */ | |
396 | } | |
397 | ||
398 | static int dccp_feat_sp(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) | |
399 | { | |
a4bf3902 | 400 | struct dccp_minisock *dmsk = dccp_msk(sk); |
afe00251 AB |
401 | struct dccp_opt_pend *opt; |
402 | int rc = 1; | |
403 | u8 t; | |
404 | ||
405 | /* | |
406 | * We received a CHANGE. We gotta match it against our own preference | |
407 | * list. If we got a CHANGE_R it means it's a change for us, so we need | |
408 | * to compare our CHANGE_L list. | |
409 | */ | |
410 | if (type == DCCPO_CHANGE_L) | |
411 | t = DCCPO_CHANGE_R; | |
412 | else | |
413 | t = DCCPO_CHANGE_L; | |
414 | ||
415 | /* find our preference list for this feature */ | |
a4bf3902 | 416 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
417 | if (opt->dccpop_type != t || opt->dccpop_feat != feature) |
418 | continue; | |
419 | ||
420 | /* find the winner from the two preference lists */ | |
421 | rc = dccp_feat_reconcile(sk, opt, val, len); | |
422 | break; | |
423 | } | |
424 | ||
425 | /* We didn't deal with the change. This can happen if we have no | |
426 | * preference list for the feature. In fact, it just shouldn't | |
427 | * happen---if we understand a feature, we should have a preference list | |
428 | * with at least the default value. | |
429 | */ | |
430 | BUG_ON(rc == 1); | |
431 | ||
432 | return rc; | |
433 | } | |
434 | ||
435 | static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) | |
436 | { | |
437 | struct dccp_opt_pend *opt; | |
a4bf3902 | 438 | struct dccp_minisock *dmsk = dccp_msk(sk); |
afe00251 AB |
439 | u8 *copy; |
440 | int rc; | |
441 | ||
c02fdc0e GR |
442 | /* NN features must be Change L (sec. 6.3.2) */ |
443 | if (type != DCCPO_CHANGE_L) { | |
444 | dccp_pr_debug("received %s for NN feature %d\n", | |
445 | dccp_feat_typename(type), feature); | |
afe00251 AB |
446 | return -EFAULT; |
447 | } | |
448 | ||
449 | /* XXX sanity check opt val */ | |
450 | ||
451 | /* copy option so we can confirm it */ | |
452 | opt = kzalloc(sizeof(*opt), GFP_ATOMIC); | |
453 | if (opt == NULL) | |
454 | return -ENOMEM; | |
455 | ||
eed73417 | 456 | copy = kmemdup(val, len, GFP_ATOMIC); |
afe00251 AB |
457 | if (copy == NULL) { |
458 | kfree(opt); | |
459 | return -ENOMEM; | |
460 | } | |
afe00251 AB |
461 | |
462 | opt->dccpop_type = DCCPO_CONFIRM_R; /* NN can only confirm R */ | |
463 | opt->dccpop_feat = feature; | |
464 | opt->dccpop_val = copy; | |
465 | opt->dccpop_len = len; | |
466 | ||
467 | /* change feature */ | |
468 | rc = dccp_feat_update(sk, type, feature, *val); | |
469 | if (rc) { | |
470 | kfree(opt->dccpop_val); | |
471 | kfree(opt); | |
472 | return rc; | |
473 | } | |
474 | ||
c02fdc0e GR |
475 | dccp_feat_debug(type, feature, *copy); |
476 | ||
a4bf3902 | 477 | list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf); |
afe00251 AB |
478 | |
479 | return 0; | |
480 | } | |
481 | ||
8ca0d17b ACM |
482 | static void dccp_feat_empty_confirm(struct dccp_minisock *dmsk, |
483 | u8 type, u8 feature) | |
afe00251 | 484 | { |
afe00251 AB |
485 | /* XXX check if other confirms for that are queued and recycle slot */ |
486 | struct dccp_opt_pend *opt = kzalloc(sizeof(*opt), GFP_ATOMIC); | |
487 | ||
488 | if (opt == NULL) { | |
489 | /* XXX what do we do? Ignoring should be fine. It's a change | |
490 | * after all =P | |
491 | */ | |
492 | return; | |
493 | } | |
494 | ||
c02fdc0e | 495 | switch (type) { |
e576de82 JJ |
496 | case DCCPO_CHANGE_L: |
497 | opt->dccpop_type = DCCPO_CONFIRM_R; | |
498 | break; | |
499 | case DCCPO_CHANGE_R: | |
500 | opt->dccpop_type = DCCPO_CONFIRM_L; | |
501 | break; | |
502 | default: | |
503 | DCCP_WARN("invalid type %d\n", type); | |
504 | kfree(opt); | |
505 | return; | |
c02fdc0e | 506 | } |
afe00251 | 507 | opt->dccpop_feat = feature; |
68907dad | 508 | opt->dccpop_val = NULL; |
afe00251 AB |
509 | opt->dccpop_len = 0; |
510 | ||
511 | /* change feature */ | |
c02fdc0e GR |
512 | dccp_pr_debug("Empty %s(%d)\n", dccp_feat_typename(type), feature); |
513 | ||
a4bf3902 | 514 | list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf); |
afe00251 AB |
515 | } |
516 | ||
517 | static void dccp_feat_flush_confirm(struct sock *sk) | |
518 | { | |
a4bf3902 | 519 | struct dccp_minisock *dmsk = dccp_msk(sk); |
afe00251 | 520 | /* Check if there is anything to confirm in the first place */ |
a4bf3902 | 521 | int yes = !list_empty(&dmsk->dccpms_conf); |
afe00251 AB |
522 | |
523 | if (!yes) { | |
524 | struct dccp_opt_pend *opt; | |
525 | ||
a4bf3902 | 526 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
527 | if (opt->dccpop_conf) { |
528 | yes = 1; | |
529 | break; | |
530 | } | |
531 | } | |
532 | } | |
533 | ||
534 | if (!yes) | |
535 | return; | |
536 | ||
537 | /* OK there is something to confirm... */ | |
538 | /* XXX check if packet is in flight? Send delayed ack?? */ | |
539 | if (sk->sk_state == DCCP_OPEN) | |
540 | dccp_send_ack(sk); | |
541 | } | |
542 | ||
543 | int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) | |
544 | { | |
545 | int rc; | |
546 | ||
f74e91b6 GR |
547 | /* Ignore Change requests other than during connection setup */ |
548 | if (sk->sk_state != DCCP_LISTEN && sk->sk_state != DCCP_REQUESTING) | |
549 | return 0; | |
c02fdc0e | 550 | dccp_feat_debug(type, feature, *val); |
afe00251 AB |
551 | |
552 | /* figure out if it's SP or NN feature */ | |
553 | switch (feature) { | |
554 | /* deal with SP features */ | |
555 | case DCCPF_CCID: | |
556 | rc = dccp_feat_sp(sk, type, feature, val, len); | |
557 | break; | |
558 | ||
559 | /* deal with NN features */ | |
560 | case DCCPF_ACK_RATIO: | |
561 | rc = dccp_feat_nn(sk, type, feature, val, len); | |
562 | break; | |
563 | ||
564 | /* XXX implement other features */ | |
565 | default: | |
c02fdc0e GR |
566 | dccp_pr_debug("UNIMPLEMENTED: not handling %s(%d, ...)\n", |
567 | dccp_feat_typename(type), feature); | |
afe00251 AB |
568 | rc = -EFAULT; |
569 | break; | |
570 | } | |
571 | ||
572 | /* check if there were problems changing features */ | |
573 | if (rc) { | |
574 | /* If we don't agree on SP, we sent a confirm for old value. | |
575 | * However we propagate rc to caller in case option was | |
576 | * mandatory | |
577 | */ | |
578 | if (rc != DCCP_FEAT_SP_NOAGREE) | |
8ca0d17b | 579 | dccp_feat_empty_confirm(dccp_msk(sk), type, feature); |
afe00251 AB |
580 | } |
581 | ||
582 | /* generate the confirm [if required] */ | |
583 | dccp_feat_flush_confirm(sk); | |
584 | ||
585 | return rc; | |
586 | } | |
587 | ||
588 | EXPORT_SYMBOL_GPL(dccp_feat_change_recv); | |
589 | ||
590 | int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature, | |
591 | u8 *val, u8 len) | |
592 | { | |
593 | u8 t; | |
594 | struct dccp_opt_pend *opt; | |
a4bf3902 | 595 | struct dccp_minisock *dmsk = dccp_msk(sk); |
c02fdc0e | 596 | int found = 0; |
afe00251 AB |
597 | int all_confirmed = 1; |
598 | ||
f74e91b6 GR |
599 | /* Ignore Confirm options other than during connection setup */ |
600 | if (sk->sk_state != DCCP_LISTEN && sk->sk_state != DCCP_REQUESTING) | |
601 | return 0; | |
c02fdc0e | 602 | dccp_feat_debug(type, feature, *val); |
afe00251 AB |
603 | |
604 | /* locate our change request */ | |
c02fdc0e GR |
605 | switch (type) { |
606 | case DCCPO_CONFIRM_L: t = DCCPO_CHANGE_R; break; | |
607 | case DCCPO_CONFIRM_R: t = DCCPO_CHANGE_L; break; | |
8109b02b | 608 | default: DCCP_WARN("invalid type %d\n", type); |
c02fdc0e GR |
609 | return 1; |
610 | ||
611 | } | |
612 | /* XXX sanity check feature value */ | |
afe00251 | 613 | |
a4bf3902 | 614 | list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
615 | if (!opt->dccpop_conf && opt->dccpop_type == t && |
616 | opt->dccpop_feat == feature) { | |
c02fdc0e GR |
617 | found = 1; |
618 | dccp_pr_debug("feature %d found\n", opt->dccpop_feat); | |
619 | ||
afe00251 AB |
620 | /* XXX do sanity check */ |
621 | ||
622 | opt->dccpop_conf = 1; | |
623 | ||
624 | /* We got a confirmation---change the option */ | |
625 | dccp_feat_update(sk, opt->dccpop_type, | |
626 | opt->dccpop_feat, *val); | |
627 | ||
c02fdc0e | 628 | /* XXX check the return value of dccp_feat_update */ |
afe00251 AB |
629 | break; |
630 | } | |
631 | ||
632 | if (!opt->dccpop_conf) | |
633 | all_confirmed = 0; | |
634 | } | |
635 | ||
c02fdc0e GR |
636 | if (!found) |
637 | dccp_pr_debug("%s(%d, ...) never requested\n", | |
638 | dccp_feat_typename(type), feature); | |
afe00251 AB |
639 | return 0; |
640 | } | |
641 | ||
642 | EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv); | |
643 | ||
8ca0d17b | 644 | void dccp_feat_clean(struct dccp_minisock *dmsk) |
afe00251 | 645 | { |
afe00251 AB |
646 | struct dccp_opt_pend *opt, *next; |
647 | ||
a4bf3902 | 648 | list_for_each_entry_safe(opt, next, &dmsk->dccpms_pending, |
afe00251 | 649 | dccpop_node) { |
c9eaf173 YH |
650 | BUG_ON(opt->dccpop_val == NULL); |
651 | kfree(opt->dccpop_val); | |
afe00251 AB |
652 | |
653 | if (opt->dccpop_sc != NULL) { | |
654 | BUG_ON(opt->dccpop_sc->dccpoc_val == NULL); | |
655 | kfree(opt->dccpop_sc->dccpoc_val); | |
656 | kfree(opt->dccpop_sc); | |
657 | } | |
658 | ||
c9eaf173 YH |
659 | kfree(opt); |
660 | } | |
a4bf3902 | 661 | INIT_LIST_HEAD(&dmsk->dccpms_pending); |
afe00251 | 662 | |
a4bf3902 | 663 | list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) { |
afe00251 AB |
664 | BUG_ON(opt == NULL); |
665 | if (opt->dccpop_val != NULL) | |
666 | kfree(opt->dccpop_val); | |
667 | kfree(opt); | |
668 | } | |
a4bf3902 | 669 | INIT_LIST_HEAD(&dmsk->dccpms_conf); |
afe00251 AB |
670 | } |
671 | ||
672 | EXPORT_SYMBOL_GPL(dccp_feat_clean); | |
673 | ||
674 | /* this is to be called only when a listening sock creates its child. It is | |
675 | * assumed by the function---the confirm is not duplicated, but rather it is | |
676 | * "passed on". | |
677 | */ | |
678 | int dccp_feat_clone(struct sock *oldsk, struct sock *newsk) | |
679 | { | |
a4bf3902 ACM |
680 | struct dccp_minisock *olddmsk = dccp_msk(oldsk); |
681 | struct dccp_minisock *newdmsk = dccp_msk(newsk); | |
afe00251 AB |
682 | struct dccp_opt_pend *opt; |
683 | int rc = 0; | |
684 | ||
a4bf3902 ACM |
685 | INIT_LIST_HEAD(&newdmsk->dccpms_pending); |
686 | INIT_LIST_HEAD(&newdmsk->dccpms_conf); | |
afe00251 | 687 | |
a4bf3902 | 688 | list_for_each_entry(opt, &olddmsk->dccpms_pending, dccpop_node) { |
afe00251 AB |
689 | struct dccp_opt_pend *newopt; |
690 | /* copy the value of the option */ | |
eed73417 | 691 | u8 *val = kmemdup(opt->dccpop_val, opt->dccpop_len, GFP_ATOMIC); |
afe00251 AB |
692 | |
693 | if (val == NULL) | |
694 | goto out_clean; | |
afe00251 | 695 | |
eed73417 | 696 | newopt = kmemdup(opt, sizeof(*newopt), GFP_ATOMIC); |
afe00251 AB |
697 | if (newopt == NULL) { |
698 | kfree(val); | |
699 | goto out_clean; | |
700 | } | |
701 | ||
702 | /* insert the option */ | |
afe00251 | 703 | newopt->dccpop_val = val; |
a4bf3902 | 704 | list_add_tail(&newopt->dccpop_node, &newdmsk->dccpms_pending); |
afe00251 AB |
705 | |
706 | /* XXX what happens with backlogs and multiple connections at | |
707 | * once... | |
708 | */ | |
709 | /* the master socket no longer needs to worry about confirms */ | |
68907dad | 710 | opt->dccpop_sc = NULL; /* it's not a memleak---new socket has it */ |
afe00251 AB |
711 | |
712 | /* reset state for a new socket */ | |
713 | opt->dccpop_conf = 0; | |
714 | } | |
715 | ||
716 | /* XXX not doing anything about the conf queue */ | |
717 | ||
718 | out: | |
719 | return rc; | |
720 | ||
721 | out_clean: | |
8ca0d17b | 722 | dccp_feat_clean(newdmsk); |
afe00251 AB |
723 | rc = -ENOMEM; |
724 | goto out; | |
725 | } | |
726 | ||
727 | EXPORT_SYMBOL_GPL(dccp_feat_clone); | |
728 | ||
8ca0d17b ACM |
729 | static int __dccp_feat_init(struct dccp_minisock *dmsk, u8 type, u8 feat, |
730 | u8 *val, u8 len) | |
afe00251 AB |
731 | { |
732 | int rc = -ENOMEM; | |
eed73417 | 733 | u8 *copy = kmemdup(val, len, GFP_KERNEL); |
afe00251 AB |
734 | |
735 | if (copy != NULL) { | |
8ca0d17b | 736 | rc = dccp_feat_change(dmsk, type, feat, copy, len, GFP_KERNEL); |
afe00251 AB |
737 | if (rc) |
738 | kfree(copy); | |
739 | } | |
740 | return rc; | |
741 | } | |
742 | ||
8ca0d17b | 743 | int dccp_feat_init(struct dccp_minisock *dmsk) |
afe00251 | 744 | { |
afe00251 AB |
745 | int rc; |
746 | ||
a4bf3902 ACM |
747 | INIT_LIST_HEAD(&dmsk->dccpms_pending); |
748 | INIT_LIST_HEAD(&dmsk->dccpms_conf); | |
afe00251 AB |
749 | |
750 | /* CCID L */ | |
8ca0d17b | 751 | rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_CCID, |
a4bf3902 | 752 | &dmsk->dccpms_tx_ccid, 1); |
afe00251 AB |
753 | if (rc) |
754 | goto out; | |
755 | ||
756 | /* CCID R */ | |
8ca0d17b | 757 | rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_R, DCCPF_CCID, |
a4bf3902 | 758 | &dmsk->dccpms_rx_ccid, 1); |
afe00251 AB |
759 | if (rc) |
760 | goto out; | |
761 | ||
762 | /* Ack ratio */ | |
8ca0d17b | 763 | rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO, |
a4bf3902 | 764 | &dmsk->dccpms_ack_ratio, 1); |
afe00251 AB |
765 | out: |
766 | return rc; | |
767 | } | |
768 | ||
769 | EXPORT_SYMBOL_GPL(dccp_feat_init); | |
c02fdc0e GR |
770 | |
771 | #ifdef CONFIG_IP_DCCP_DEBUG | |
772 | const char *dccp_feat_typename(const u8 type) | |
773 | { | |
774 | switch(type) { | |
775 | case DCCPO_CHANGE_L: return("ChangeL"); | |
776 | case DCCPO_CONFIRM_L: return("ConfirmL"); | |
777 | case DCCPO_CHANGE_R: return("ChangeR"); | |
778 | case DCCPO_CONFIRM_R: return("ConfirmR"); | |
779 | /* the following case must not appear in feature negotation */ | |
8109b02b | 780 | default: dccp_pr_debug("unknown type %d [BUG!]\n", type); |
c02fdc0e GR |
781 | } |
782 | return NULL; | |
783 | } | |
784 | ||
785 | EXPORT_SYMBOL_GPL(dccp_feat_typename); | |
786 | ||
787 | const char *dccp_feat_name(const u8 feat) | |
788 | { | |
789 | static const char *feature_names[] = { | |
790 | [DCCPF_RESERVED] = "Reserved", | |
791 | [DCCPF_CCID] = "CCID", | |
792 | [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos", | |
793 | [DCCPF_SEQUENCE_WINDOW] = "Sequence Window", | |
794 | [DCCPF_ECN_INCAPABLE] = "ECN Incapable", | |
795 | [DCCPF_ACK_RATIO] = "Ack Ratio", | |
796 | [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector", | |
797 | [DCCPF_SEND_NDP_COUNT] = "Send NDP Count", | |
798 | [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage", | |
799 | [DCCPF_DATA_CHECKSUM] = "Send Data Checksum", | |
800 | }; | |
dd6303df GR |
801 | if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC) |
802 | return feature_names[DCCPF_RESERVED]; | |
803 | ||
7d43d1a0 GR |
804 | if (feat == DCCPF_SEND_LEV_RATE) |
805 | return "Send Loss Event Rate"; | |
c02fdc0e GR |
806 | if (feat >= DCCPF_MIN_CCID_SPECIFIC) |
807 | return "CCID-specific"; | |
808 | ||
c02fdc0e GR |
809 | return feature_names[feat]; |
810 | } | |
811 | ||
812 | EXPORT_SYMBOL_GPL(dccp_feat_name); | |
813 | #endif /* CONFIG_IP_DCCP_DEBUG */ |