4 * An implementation of the DCCP protocol
5 * Andrea Bittau <a.bittau@cs.ucl.ac.uk>
9 * o Feature negotiation is coordinated with connection setup (as in TCP), wild
10 * changes of parameters of an established connection are not supported.
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.
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.
21 #include <linux/module.h>
26 #define DCCP_FEAT_SP_NOAGREE (-123)
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 */
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 * +--------------------------+----+-----+----+----+---------+-----------+
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 },
63 #define DCCP_FEAT_SUPPORTED_MAX ARRAY_SIZE(dccp_feat_table)
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.
69 static int dccp_feat_index(u8 feat_num
)
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
)
76 * Other features: add cases for new feature types here after adding
77 * them to the above table.
80 case DCCPF_SEND_LEV_RATE
:
81 return DCCP_FEAT_SUPPORTED_MAX
- 1;
86 static u8
dccp_feat_type(u8 feat_num
)
88 int idx
= dccp_feat_index(feat_num
);
92 return dccp_feat_table
[idx
].reconciliation
;
95 static int dccp_feat_default_value(u8 feat_num
)
97 int idx
= dccp_feat_index(feat_num
);
99 * There are no default values for unknown features, so encountering a
100 * negative index here indicates a serious problem somewhere else.
102 DCCP_BUG_ON(idx
< 0);
104 return idx
< 0 ? 0 : dccp_feat_table
[idx
].default_value
;
107 /* copy constructor, fval must not already contain allocated memory */
108 static int dccp_feat_clone_sp_val(dccp_feat_val
*fval
, u8
const *val
, u8 len
)
111 if (fval
->sp
.len
> 0) {
112 fval
->sp
.vec
= kmemdup(val
, len
, gfp_any());
113 if (fval
->sp
.vec
== NULL
) {
121 static void dccp_feat_val_destructor(u8 feat_num
, dccp_feat_val
*val
)
123 if (unlikely(val
== NULL
))
125 if (dccp_feat_type(feat_num
) == FEAT_SP
)
127 memset(val
, 0, sizeof(*val
));
130 static struct dccp_feat_entry
*
131 dccp_feat_clone_entry(struct dccp_feat_entry
const *original
)
133 struct dccp_feat_entry
*new;
134 u8 type
= dccp_feat_type(original
->feat_num
);
136 if (type
== FEAT_UNKNOWN
)
139 new = kmemdup(original
, sizeof(struct dccp_feat_entry
), gfp_any());
143 if (type
== FEAT_SP
&& dccp_feat_clone_sp_val(&new->val
,
144 original
->val
.sp
.vec
,
145 original
->val
.sp
.len
)) {
152 static void dccp_feat_entry_destructor(struct dccp_feat_entry
*entry
)
155 dccp_feat_val_destructor(entry
->feat_num
, &entry
->val
);
161 * List management functions
163 * Feature negotiation lists rely on and maintain the following invariants:
164 * - each feat_num in the list is known, i.e. we know its type and default value
165 * - each feat_num/is_local combination is unique (old entries are overwritten)
166 * - SP values are always freshly allocated
167 * - list is sorted in increasing order of feature number (faster lookup)
171 * dccp_feat_entry_new - Central list update routine (called by all others)
172 * @head: list to add to
173 * @feat: feature number
174 * @local: whether the local (1) or remote feature with number @feat is meant
175 * This is the only constructor and serves to ensure the above invariants.
177 static struct dccp_feat_entry
*
178 dccp_feat_entry_new(struct list_head
*head
, u8 feat
, bool local
)
180 struct dccp_feat_entry
*entry
;
182 list_for_each_entry(entry
, head
, node
)
183 if (entry
->feat_num
== feat
&& entry
->is_local
== local
) {
184 dccp_feat_val_destructor(entry
->feat_num
, &entry
->val
);
186 } else if (entry
->feat_num
> feat
) {
191 entry
= kmalloc(sizeof(*entry
), gfp_any());
193 entry
->feat_num
= feat
;
194 entry
->is_local
= local
;
195 list_add_tail(&entry
->node
, head
);
201 * dccp_feat_push_change - Add/overwrite a Change option in the list
202 * @fn_list: feature-negotiation list to update
203 * @feat: one of %dccp_feature_numbers
204 * @local: whether local (1) or remote (0) @feat_num is meant
205 * @needs_mandatory: whether to use Mandatory feature negotiation options
206 * @fval: pointer to NN/SP value to be inserted (will be copied)
208 static int dccp_feat_push_change(struct list_head
*fn_list
, u8 feat
, u8 local
,
209 u8 mandatory
, dccp_feat_val
*fval
)
211 struct dccp_feat_entry
*new = dccp_feat_entry_new(fn_list
, feat
, local
);
216 new->feat_num
= feat
;
217 new->is_local
= local
;
218 new->state
= FEAT_INITIALISING
;
219 new->needs_confirm
= 0;
220 new->empty_confirm
= 0;
222 new->needs_mandatory
= mandatory
;
227 static inline void dccp_feat_list_pop(struct dccp_feat_entry
*entry
)
229 list_del(&entry
->node
);
230 dccp_feat_entry_destructor(entry
);
233 void dccp_feat_list_purge(struct list_head
*fn_list
)
235 struct dccp_feat_entry
*entry
, *next
;
237 list_for_each_entry_safe(entry
, next
, fn_list
, node
)
238 dccp_feat_entry_destructor(entry
);
239 INIT_LIST_HEAD(fn_list
);
241 EXPORT_SYMBOL_GPL(dccp_feat_list_purge
);
243 /* generate @to as full clone of @from - @to must not contain any nodes */
244 int dccp_feat_clone_list(struct list_head
const *from
, struct list_head
*to
)
246 struct dccp_feat_entry
*entry
, *new;
249 list_for_each_entry(entry
, from
, node
) {
250 new = dccp_feat_clone_entry(entry
);
253 list_add_tail(&new->node
, to
);
258 dccp_feat_list_purge(to
);
262 static u8
dccp_feat_is_valid_nn_val(u8 feat_num
, u64 val
)
265 case DCCPF_ACK_RATIO
:
266 return val
<= DCCPF_ACK_RATIO_MAX
;
267 case DCCPF_SEQUENCE_WINDOW
:
268 return val
>= DCCPF_SEQ_WMIN
&& val
<= DCCPF_SEQ_WMAX
;
270 return 0; /* feature unknown - so we can't tell */
273 /* check that SP values are within the ranges defined in RFC 4340 */
274 static u8
dccp_feat_is_valid_sp_val(u8 feat_num
, u8 val
)
278 return val
== DCCPC_CCID2
|| val
== DCCPC_CCID3
;
279 /* Type-check Boolean feature values: */
280 case DCCPF_SHORT_SEQNOS
:
281 case DCCPF_ECN_INCAPABLE
:
282 case DCCPF_SEND_ACK_VECTOR
:
283 case DCCPF_SEND_NDP_COUNT
:
284 case DCCPF_DATA_CHECKSUM
:
285 case DCCPF_SEND_LEV_RATE
:
287 case DCCPF_MIN_CSUM_COVER
:
290 return 0; /* feature unknown */
293 static u8
dccp_feat_sp_list_ok(u8 feat_num
, u8
const *sp_list
, u8 sp_len
)
295 if (sp_list
== NULL
|| sp_len
< 1)
298 if (!dccp_feat_is_valid_sp_val(feat_num
, *sp_list
++))
304 * __feat_register_nn - Register new NN value on socket
305 * @fn: feature-negotiation list to register with
306 * @feat: an NN feature from %dccp_feature_numbers
307 * @mandatory: use Mandatory option if 1
308 * @nn_val: value to register (restricted to 4 bytes)
309 * Note that NN features are local by definition (RFC 4340, 6.3.2).
311 static int __feat_register_nn(struct list_head
*fn
, u8 feat
,
312 u8 mandatory
, u64 nn_val
)
314 dccp_feat_val fval
= { .nn
= nn_val
};
316 if (dccp_feat_type(feat
) != FEAT_NN
||
317 !dccp_feat_is_valid_nn_val(feat
, nn_val
))
320 /* Don't bother with default values, they will be activated anyway. */
321 if (nn_val
- (u64
)dccp_feat_default_value(feat
) == 0)
324 return dccp_feat_push_change(fn
, feat
, 1, mandatory
, &fval
);
328 * __feat_register_sp - Register new SP value/list on socket
329 * @fn: feature-negotiation list to register with
330 * @feat: an SP feature from %dccp_feature_numbers
331 * @is_local: whether the local (1) or the remote (0) @feat is meant
332 * @mandatory: use Mandatory option if 1
333 * @sp_val: SP value followed by optional preference list
334 * @sp_len: length of @sp_val in bytes
336 static int __feat_register_sp(struct list_head
*fn
, u8 feat
, u8 is_local
,
337 u8 mandatory
, u8
const *sp_val
, u8 sp_len
)
341 if (dccp_feat_type(feat
) != FEAT_SP
||
342 !dccp_feat_sp_list_ok(feat
, sp_val
, sp_len
))
345 /* Avoid negotiating alien CCIDs by only advertising supported ones */
346 if (feat
== DCCPF_CCID
&& !ccid_support_check(sp_val
, sp_len
))
349 if (dccp_feat_clone_sp_val(&fval
, sp_val
, sp_len
))
352 return dccp_feat_push_change(fn
, feat
, is_local
, mandatory
, &fval
);
355 int dccp_feat_change(struct dccp_minisock
*dmsk
, u8 type
, u8 feature
,
356 u8
*val
, u8 len
, gfp_t gfp
)
358 struct dccp_opt_pend
*opt
;
360 dccp_feat_debug(type
, feature
, *val
);
363 DCCP_WARN("invalid length %d\n", len
);
366 /* XXX add further sanity checks */
368 /* check if that feature is already being negotiated */
369 list_for_each_entry(opt
, &dmsk
->dccpms_pending
, dccpop_node
) {
370 /* ok we found a negotiation for this option already */
371 if (opt
->dccpop_feat
== feature
&& opt
->dccpop_type
== type
) {
372 dccp_pr_debug("Replacing old\n");
374 BUG_ON(opt
->dccpop_val
== NULL
);
375 kfree(opt
->dccpop_val
);
376 opt
->dccpop_val
= val
;
377 opt
->dccpop_len
= len
;
378 opt
->dccpop_conf
= 0;
383 /* negotiation for a new feature */
384 opt
= kmalloc(sizeof(*opt
), gfp
);
388 opt
->dccpop_type
= type
;
389 opt
->dccpop_feat
= feature
;
390 opt
->dccpop_len
= len
;
391 opt
->dccpop_val
= val
;
392 opt
->dccpop_conf
= 0;
393 opt
->dccpop_sc
= NULL
;
395 BUG_ON(opt
->dccpop_val
== NULL
);
397 list_add_tail(&opt
->dccpop_node
, &dmsk
->dccpms_pending
);
401 EXPORT_SYMBOL_GPL(dccp_feat_change
);
403 static int dccp_feat_update_ccid(struct sock
*sk
, u8 type
, u8 new_ccid_nr
)
405 struct dccp_sock
*dp
= dccp_sk(sk
);
406 struct dccp_minisock
*dmsk
= dccp_msk(sk
);
407 /* figure out if we are changing our CCID or the peer's */
408 const int rx
= type
== DCCPO_CHANGE_R
;
409 const u8 ccid_nr
= rx
? dmsk
->dccpms_rx_ccid
: dmsk
->dccpms_tx_ccid
;
410 struct ccid
*new_ccid
;
412 /* Check if nothing is being changed. */
413 if (ccid_nr
== new_ccid_nr
)
416 new_ccid
= ccid_new(new_ccid_nr
, sk
, rx
, GFP_ATOMIC
);
417 if (new_ccid
== NULL
)
421 ccid_hc_rx_delete(dp
->dccps_hc_rx_ccid
, sk
);
422 dp
->dccps_hc_rx_ccid
= new_ccid
;
423 dmsk
->dccpms_rx_ccid
= new_ccid_nr
;
425 ccid_hc_tx_delete(dp
->dccps_hc_tx_ccid
, sk
);
426 dp
->dccps_hc_tx_ccid
= new_ccid
;
427 dmsk
->dccpms_tx_ccid
= new_ccid_nr
;
433 static int dccp_feat_update(struct sock
*sk
, u8 type
, u8 feat
, u8 val
)
435 dccp_feat_debug(type
, feat
, val
);
439 return dccp_feat_update_ccid(sk
, type
, val
);
441 dccp_pr_debug("UNIMPLEMENTED: %s(%d, ...)\n",
442 dccp_feat_typename(type
), feat
);
448 static int dccp_feat_reconcile(struct sock
*sk
, struct dccp_opt_pend
*opt
,
451 struct dccp_sock
*dp
= dccp_sk(sk
);
452 u8
*spref
, slen
, *res
= NULL
;
453 int i
, j
, rc
, agree
= 1;
455 BUG_ON(rpref
== NULL
);
457 /* check if we are the black sheep */
458 if (dp
->dccps_role
== DCCP_ROLE_CLIENT
) {
461 rpref
= opt
->dccpop_val
;
462 rlen
= opt
->dccpop_len
;
464 spref
= opt
->dccpop_val
;
465 slen
= opt
->dccpop_len
;
468 * Now we have server preference list in spref and client preference in
471 BUG_ON(spref
== NULL
);
472 BUG_ON(rpref
== NULL
);
474 /* FIXME sanity check vals */
476 /* Are values in any order? XXX Lame "algorithm" here */
477 for (i
= 0; i
< slen
; i
++) {
478 for (j
= 0; j
< rlen
; j
++) {
479 if (spref
[i
] == rpref
[j
]) {
488 /* we didn't agree on anything */
490 /* confirm previous value */
491 switch (opt
->dccpop_feat
) {
493 /* XXX did i get this right? =P */
494 if (opt
->dccpop_type
== DCCPO_CHANGE_L
)
495 res
= &dccp_msk(sk
)->dccpms_tx_ccid
;
497 res
= &dccp_msk(sk
)->dccpms_rx_ccid
;
501 DCCP_BUG("Fell through, feat=%d", opt
->dccpop_feat
);
502 /* XXX implement res */
506 dccp_pr_debug("Don't agree... reconfirming %d\n", *res
);
507 agree
= 0; /* this is used for mandatory options... */
510 /* need to put result and our preference list */
511 rlen
= 1 + opt
->dccpop_len
;
512 rpref
= kmalloc(rlen
, GFP_ATOMIC
);
517 memcpy(&rpref
[1], opt
->dccpop_val
, opt
->dccpop_len
);
519 /* put it in the "confirm queue" */
520 if (opt
->dccpop_sc
== NULL
) {
521 opt
->dccpop_sc
= kmalloc(sizeof(*opt
->dccpop_sc
), GFP_ATOMIC
);
522 if (opt
->dccpop_sc
== NULL
) {
527 /* recycle the confirm slot */
528 BUG_ON(opt
->dccpop_sc
->dccpoc_val
== NULL
);
529 kfree(opt
->dccpop_sc
->dccpoc_val
);
530 dccp_pr_debug("recycling confirm slot\n");
532 memset(opt
->dccpop_sc
, 0, sizeof(*opt
->dccpop_sc
));
534 opt
->dccpop_sc
->dccpoc_val
= rpref
;
535 opt
->dccpop_sc
->dccpoc_len
= rlen
;
537 /* update the option on our side [we are about to send the confirm] */
538 rc
= dccp_feat_update(sk
, opt
->dccpop_type
, opt
->dccpop_feat
, *res
);
540 kfree(opt
->dccpop_sc
->dccpoc_val
);
541 kfree(opt
->dccpop_sc
);
542 opt
->dccpop_sc
= NULL
;
546 dccp_pr_debug("Will confirm %d\n", *rpref
);
548 /* say we want to change to X but we just got a confirm X, suppress our
551 if (!opt
->dccpop_conf
) {
552 if (*opt
->dccpop_val
== *res
)
553 opt
->dccpop_conf
= 1;
554 dccp_pr_debug("won't ask for change of same feature\n");
557 return agree
? 0 : DCCP_FEAT_SP_NOAGREE
; /* used for mandatory opts */
560 static int dccp_feat_sp(struct sock
*sk
, u8 type
, u8 feature
, u8
*val
, u8 len
)
562 struct dccp_minisock
*dmsk
= dccp_msk(sk
);
563 struct dccp_opt_pend
*opt
;
568 * We received a CHANGE. We gotta match it against our own preference
569 * list. If we got a CHANGE_R it means it's a change for us, so we need
570 * to compare our CHANGE_L list.
572 if (type
== DCCPO_CHANGE_L
)
577 /* find our preference list for this feature */
578 list_for_each_entry(opt
, &dmsk
->dccpms_pending
, dccpop_node
) {
579 if (opt
->dccpop_type
!= t
|| opt
->dccpop_feat
!= feature
)
582 /* find the winner from the two preference lists */
583 rc
= dccp_feat_reconcile(sk
, opt
, val
, len
);
587 /* We didn't deal with the change. This can happen if we have no
588 * preference list for the feature. In fact, it just shouldn't
589 * happen---if we understand a feature, we should have a preference list
590 * with at least the default value.
597 static int dccp_feat_nn(struct sock
*sk
, u8 type
, u8 feature
, u8
*val
, u8 len
)
599 struct dccp_opt_pend
*opt
;
600 struct dccp_minisock
*dmsk
= dccp_msk(sk
);
604 /* NN features must be Change L (sec. 6.3.2) */
605 if (type
!= DCCPO_CHANGE_L
) {
606 dccp_pr_debug("received %s for NN feature %d\n",
607 dccp_feat_typename(type
), feature
);
611 /* XXX sanity check opt val */
613 /* copy option so we can confirm it */
614 opt
= kzalloc(sizeof(*opt
), GFP_ATOMIC
);
618 copy
= kmemdup(val
, len
, GFP_ATOMIC
);
624 opt
->dccpop_type
= DCCPO_CONFIRM_R
; /* NN can only confirm R */
625 opt
->dccpop_feat
= feature
;
626 opt
->dccpop_val
= copy
;
627 opt
->dccpop_len
= len
;
630 rc
= dccp_feat_update(sk
, type
, feature
, *val
);
632 kfree(opt
->dccpop_val
);
637 dccp_feat_debug(type
, feature
, *copy
);
639 list_add_tail(&opt
->dccpop_node
, &dmsk
->dccpms_conf
);
644 static void dccp_feat_empty_confirm(struct dccp_minisock
*dmsk
,
647 /* XXX check if other confirms for that are queued and recycle slot */
648 struct dccp_opt_pend
*opt
= kzalloc(sizeof(*opt
), GFP_ATOMIC
);
651 /* XXX what do we do? Ignoring should be fine. It's a change
659 opt
->dccpop_type
= DCCPO_CONFIRM_R
;
662 opt
->dccpop_type
= DCCPO_CONFIRM_L
;
665 DCCP_WARN("invalid type %d\n", type
);
669 opt
->dccpop_feat
= feature
;
670 opt
->dccpop_val
= NULL
;
674 dccp_pr_debug("Empty %s(%d)\n", dccp_feat_typename(type
), feature
);
676 list_add_tail(&opt
->dccpop_node
, &dmsk
->dccpms_conf
);
679 static void dccp_feat_flush_confirm(struct sock
*sk
)
681 struct dccp_minisock
*dmsk
= dccp_msk(sk
);
682 /* Check if there is anything to confirm in the first place */
683 int yes
= !list_empty(&dmsk
->dccpms_conf
);
686 struct dccp_opt_pend
*opt
;
688 list_for_each_entry(opt
, &dmsk
->dccpms_pending
, dccpop_node
) {
689 if (opt
->dccpop_conf
) {
699 /* OK there is something to confirm... */
700 /* XXX check if packet is in flight? Send delayed ack?? */
701 if (sk
->sk_state
== DCCP_OPEN
)
705 int dccp_feat_change_recv(struct sock
*sk
, u8 type
, u8 feature
, u8
*val
, u8 len
)
709 /* Ignore Change requests other than during connection setup */
710 if (sk
->sk_state
!= DCCP_LISTEN
&& sk
->sk_state
!= DCCP_REQUESTING
)
712 dccp_feat_debug(type
, feature
, *val
);
714 /* figure out if it's SP or NN feature */
716 /* deal with SP features */
718 rc
= dccp_feat_sp(sk
, type
, feature
, val
, len
);
721 /* deal with NN features */
722 case DCCPF_ACK_RATIO
:
723 rc
= dccp_feat_nn(sk
, type
, feature
, val
, len
);
726 /* XXX implement other features */
728 dccp_pr_debug("UNIMPLEMENTED: not handling %s(%d, ...)\n",
729 dccp_feat_typename(type
), feature
);
734 /* check if there were problems changing features */
736 /* If we don't agree on SP, we sent a confirm for old value.
737 * However we propagate rc to caller in case option was
740 if (rc
!= DCCP_FEAT_SP_NOAGREE
)
741 dccp_feat_empty_confirm(dccp_msk(sk
), type
, feature
);
744 /* generate the confirm [if required] */
745 dccp_feat_flush_confirm(sk
);
750 EXPORT_SYMBOL_GPL(dccp_feat_change_recv
);
752 int dccp_feat_confirm_recv(struct sock
*sk
, u8 type
, u8 feature
,
756 struct dccp_opt_pend
*opt
;
757 struct dccp_minisock
*dmsk
= dccp_msk(sk
);
759 int all_confirmed
= 1;
761 /* Ignore Confirm options other than during connection setup */
762 if (sk
->sk_state
!= DCCP_LISTEN
&& sk
->sk_state
!= DCCP_REQUESTING
)
764 dccp_feat_debug(type
, feature
, *val
);
766 /* locate our change request */
768 case DCCPO_CONFIRM_L
: t
= DCCPO_CHANGE_R
; break;
769 case DCCPO_CONFIRM_R
: t
= DCCPO_CHANGE_L
; break;
770 default: DCCP_WARN("invalid type %d\n", type
);
774 /* XXX sanity check feature value */
776 list_for_each_entry(opt
, &dmsk
->dccpms_pending
, dccpop_node
) {
777 if (!opt
->dccpop_conf
&& opt
->dccpop_type
== t
&&
778 opt
->dccpop_feat
== feature
) {
780 dccp_pr_debug("feature %d found\n", opt
->dccpop_feat
);
782 /* XXX do sanity check */
784 opt
->dccpop_conf
= 1;
786 /* We got a confirmation---change the option */
787 dccp_feat_update(sk
, opt
->dccpop_type
,
788 opt
->dccpop_feat
, *val
);
790 /* XXX check the return value of dccp_feat_update */
794 if (!opt
->dccpop_conf
)
799 dccp_pr_debug("%s(%d, ...) never requested\n",
800 dccp_feat_typename(type
), feature
);
804 EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv
);
806 void dccp_feat_clean(struct dccp_minisock
*dmsk
)
808 struct dccp_opt_pend
*opt
, *next
;
810 list_for_each_entry_safe(opt
, next
, &dmsk
->dccpms_pending
,
812 BUG_ON(opt
->dccpop_val
== NULL
);
813 kfree(opt
->dccpop_val
);
815 if (opt
->dccpop_sc
!= NULL
) {
816 BUG_ON(opt
->dccpop_sc
->dccpoc_val
== NULL
);
817 kfree(opt
->dccpop_sc
->dccpoc_val
);
818 kfree(opt
->dccpop_sc
);
823 INIT_LIST_HEAD(&dmsk
->dccpms_pending
);
825 list_for_each_entry_safe(opt
, next
, &dmsk
->dccpms_conf
, dccpop_node
) {
827 if (opt
->dccpop_val
!= NULL
)
828 kfree(opt
->dccpop_val
);
831 INIT_LIST_HEAD(&dmsk
->dccpms_conf
);
834 EXPORT_SYMBOL_GPL(dccp_feat_clean
);
836 /* this is to be called only when a listening sock creates its child. It is
837 * assumed by the function---the confirm is not duplicated, but rather it is
840 int dccp_feat_clone(struct sock
*oldsk
, struct sock
*newsk
)
842 struct dccp_minisock
*olddmsk
= dccp_msk(oldsk
);
843 struct dccp_minisock
*newdmsk
= dccp_msk(newsk
);
844 struct dccp_opt_pend
*opt
;
847 INIT_LIST_HEAD(&newdmsk
->dccpms_pending
);
848 INIT_LIST_HEAD(&newdmsk
->dccpms_conf
);
850 list_for_each_entry(opt
, &olddmsk
->dccpms_pending
, dccpop_node
) {
851 struct dccp_opt_pend
*newopt
;
852 /* copy the value of the option */
853 u8
*val
= kmemdup(opt
->dccpop_val
, opt
->dccpop_len
, GFP_ATOMIC
);
858 newopt
= kmemdup(opt
, sizeof(*newopt
), GFP_ATOMIC
);
859 if (newopt
== NULL
) {
864 /* insert the option */
865 newopt
->dccpop_val
= val
;
866 list_add_tail(&newopt
->dccpop_node
, &newdmsk
->dccpms_pending
);
868 /* XXX what happens with backlogs and multiple connections at
871 /* the master socket no longer needs to worry about confirms */
872 opt
->dccpop_sc
= NULL
; /* it's not a memleak---new socket has it */
874 /* reset state for a new socket */
875 opt
->dccpop_conf
= 0;
878 /* XXX not doing anything about the conf queue */
884 dccp_feat_clean(newdmsk
);
889 EXPORT_SYMBOL_GPL(dccp_feat_clone
);
891 int dccp_feat_init(struct sock
*sk
)
893 struct dccp_sock
*dp
= dccp_sk(sk
);
894 struct dccp_minisock
*dmsk
= dccp_msk(sk
);
897 INIT_LIST_HEAD(&dmsk
->dccpms_pending
); /* XXX no longer used */
898 INIT_LIST_HEAD(&dmsk
->dccpms_conf
); /* XXX no longer used */
901 rc
= __feat_register_sp(&dp
->dccps_featneg
, DCCPF_CCID
, 1, 0,
902 &dmsk
->dccpms_tx_ccid
, 1);
907 rc
= __feat_register_sp(&dp
->dccps_featneg
, DCCPF_CCID
, 0, 0,
908 &dmsk
->dccpms_rx_ccid
, 1);
913 rc
= __feat_register_nn(&dp
->dccps_featneg
, DCCPF_ACK_RATIO
, 0,
914 dmsk
->dccpms_ack_ratio
);
919 EXPORT_SYMBOL_GPL(dccp_feat_init
);
921 #ifdef CONFIG_IP_DCCP_DEBUG
922 const char *dccp_feat_typename(const u8 type
)
925 case DCCPO_CHANGE_L
: return("ChangeL");
926 case DCCPO_CONFIRM_L
: return("ConfirmL");
927 case DCCPO_CHANGE_R
: return("ChangeR");
928 case DCCPO_CONFIRM_R
: return("ConfirmR");
929 /* the following case must not appear in feature negotation */
930 default: dccp_pr_debug("unknown type %d [BUG!]\n", type
);
935 EXPORT_SYMBOL_GPL(dccp_feat_typename
);
937 const char *dccp_feat_name(const u8 feat
)
939 static const char *feature_names
[] = {
940 [DCCPF_RESERVED
] = "Reserved",
941 [DCCPF_CCID
] = "CCID",
942 [DCCPF_SHORT_SEQNOS
] = "Allow Short Seqnos",
943 [DCCPF_SEQUENCE_WINDOW
] = "Sequence Window",
944 [DCCPF_ECN_INCAPABLE
] = "ECN Incapable",
945 [DCCPF_ACK_RATIO
] = "Ack Ratio",
946 [DCCPF_SEND_ACK_VECTOR
] = "Send ACK Vector",
947 [DCCPF_SEND_NDP_COUNT
] = "Send NDP Count",
948 [DCCPF_MIN_CSUM_COVER
] = "Min. Csum Coverage",
949 [DCCPF_DATA_CHECKSUM
] = "Send Data Checksum",
951 if (feat
> DCCPF_DATA_CHECKSUM
&& feat
< DCCPF_MIN_CCID_SPECIFIC
)
952 return feature_names
[DCCPF_RESERVED
];
954 if (feat
== DCCPF_SEND_LEV_RATE
)
955 return "Send Loss Event Rate";
956 if (feat
>= DCCPF_MIN_CCID_SPECIFIC
)
957 return "CCID-specific";
959 return feature_names
[feat
];
962 EXPORT_SYMBOL_GPL(dccp_feat_name
);
963 #endif /* CONFIG_IP_DCCP_DEBUG */