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ALSA: hda - Adding one more ALC255 pin definition for headset problem
[linux/fpc-iii.git] / net / dccp / ipv6.c
blob3828f94b234c1104a3e745b3c0a76ab343aed4b6
1 /*
2 * DCCP over IPv6
3 * Linux INET6 implementation
4 *
5 * Based on net/dccp6/ipv6.c
6 *
7 * Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
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 */
14
15 #include <linux/module.h>
16 #include <linux/random.h>
17 #include <linux/slab.h>
18 #include <linux/xfrm.h>
19
20 #include <net/addrconf.h>
21 #include <net/inet_common.h>
22 #include <net/inet_hashtables.h>
23 #include <net/inet_sock.h>
24 #include <net/inet6_connection_sock.h>
25 #include <net/inet6_hashtables.h>
26 #include <net/ip6_route.h>
27 #include <net/ipv6.h>
28 #include <net/protocol.h>
29 #include <net/transp_v6.h>
30 #include <net/ip6_checksum.h>
31 #include <net/xfrm.h>
32 #include <net/secure_seq.h>
33
34 #include "dccp.h"
35 #include "ipv6.h"
36 #include "feat.h"
37
38 /* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */
39
40 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped;
41 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
42
43 /* add pseudo-header to DCCP checksum stored in skb->csum */
44 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
45 const struct in6_addr *saddr,
46 const struct in6_addr *daddr)
47 {
48 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
49 }
50
51 static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
52 {
53 struct ipv6_pinfo *np = inet6_sk(sk);
54 struct dccp_hdr *dh = dccp_hdr(skb);
55
56 dccp_csum_outgoing(skb);
57 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr);
58 }
59
60 static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb)
61 {
62 return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
63 ipv6_hdr(skb)->saddr.s6_addr32,
64 dccp_hdr(skb)->dccph_dport,
65 dccp_hdr(skb)->dccph_sport );
66
67 }
68
69 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
70 u8 type, u8 code, int offset, __be32 info)
71 {
72 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
73 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
74 struct dccp_sock *dp;
75 struct ipv6_pinfo *np;
76 struct sock *sk;
77 int err;
78 __u64 seq;
79 struct net *net = dev_net(skb->dev);
80
81 if (skb->len < offset + sizeof(*dh) ||
82 skb->len < offset + __dccp_basic_hdr_len(dh)) {
83 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
84 ICMP6_MIB_INERRORS);
85 return;
86 }
87
88 sk = __inet6_lookup_established(net, &dccp_hashinfo,
89 &hdr->daddr, dh->dccph_dport,
90 &hdr->saddr, ntohs(dh->dccph_sport),
91 inet6_iif(skb));
92
93 if (!sk) {
94 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
95 ICMP6_MIB_INERRORS);
96 return;
97 }
98
99 if (sk->sk_state == DCCP_TIME_WAIT) {
100 inet_twsk_put(inet_twsk(sk));
101 return;
102 }
103 seq = dccp_hdr_seq(dh);
104 if (sk->sk_state == DCCP_NEW_SYN_RECV)
105 return dccp_req_err(sk, seq);
106
107 bh_lock_sock(sk);
108 if (sock_owned_by_user(sk))
109 __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
110
111 if (sk->sk_state == DCCP_CLOSED)
112 goto out;
113
114 dp = dccp_sk(sk);
115 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
116 !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
117 __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
118 goto out;
119 }
120
121 np = inet6_sk(sk);
122
123 if (type == NDISC_REDIRECT) {
124 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
125
126 if (dst)
127 dst->ops->redirect(dst, sk, skb);
128 goto out;
129 }
130
131 if (type == ICMPV6_PKT_TOOBIG) {
132 struct dst_entry *dst = NULL;
133
134 if (!ip6_sk_accept_pmtu(sk))
135 goto out;
136
137 if (sock_owned_by_user(sk))
138 goto out;
139 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
140 goto out;
141
142 dst = inet6_csk_update_pmtu(sk, ntohl(info));
143 if (!dst)
144 goto out;
145
146 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
147 dccp_sync_mss(sk, dst_mtu(dst));
148 goto out;
149 }
150
151 icmpv6_err_convert(type, code, &err);
152
153 /* Might be for an request_sock */
154 switch (sk->sk_state) {
155 case DCCP_REQUESTING:
156 case DCCP_RESPOND: /* Cannot happen.
157 It can, it SYNs are crossed. --ANK */
158 if (!sock_owned_by_user(sk)) {
159 __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS);
160 sk->sk_err = err;
161 /*
162 * Wake people up to see the error
163 * (see connect in sock.c)
164 */
165 sk->sk_error_report(sk);
166 dccp_done(sk);
167 } else
168 sk->sk_err_soft = err;
169 goto out;
170 }
171
172 if (!sock_owned_by_user(sk) && np->recverr) {
173 sk->sk_err = err;
174 sk->sk_error_report(sk);
175 } else
176 sk->sk_err_soft = err;
177
178 out:
179 bh_unlock_sock(sk);
180 sock_put(sk);
181 }
182
183
184 static int dccp_v6_send_response(const struct sock *sk, struct request_sock *req)
185 {
186 struct inet_request_sock *ireq = inet_rsk(req);
187 struct ipv6_pinfo *np = inet6_sk(sk);
188 struct sk_buff *skb;
189 struct in6_addr *final_p, final;
190 struct flowi6 fl6;
191 int err = -1;
192 struct dst_entry *dst;
193
194 memset(&fl6, 0, sizeof(fl6));
195 fl6.flowi6_proto = IPPROTO_DCCP;
196 fl6.daddr = ireq->ir_v6_rmt_addr;
197 fl6.saddr = ireq->ir_v6_loc_addr;
198 fl6.flowlabel = 0;
199 fl6.flowi6_oif = ireq->ir_iif;
200 fl6.fl6_dport = ireq->ir_rmt_port;
201 fl6.fl6_sport = htons(ireq->ir_num);
202 security_req_classify_flow(req, flowi6_to_flowi(&fl6));
203
204
205 rcu_read_lock();
206 final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt), &final);
207 rcu_read_unlock();
208
209 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
210 if (IS_ERR(dst)) {
211 err = PTR_ERR(dst);
212 dst = NULL;
213 goto done;
214 }
215
216 skb = dccp_make_response(sk, dst, req);
217 if (skb != NULL) {
218 struct dccp_hdr *dh = dccp_hdr(skb);
219 struct ipv6_txoptions *opt;
220
221 dh->dccph_checksum = dccp_v6_csum_finish(skb,
222 &ireq->ir_v6_loc_addr,
223 &ireq->ir_v6_rmt_addr);
224 fl6.daddr = ireq->ir_v6_rmt_addr;
225 rcu_read_lock();
226 opt = ireq->ipv6_opt;
227 if (!opt)
228 opt = rcu_dereference(np->opt);
229 err = ip6_xmit(sk, skb, &fl6, opt, np->tclass);
230 rcu_read_unlock();
231 err = net_xmit_eval(err);
232 }
233
234 done:
235 dst_release(dst);
236 return err;
237 }
238
239 static void dccp_v6_reqsk_destructor(struct request_sock *req)
240 {
241 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
242 kfree(inet_rsk(req)->ipv6_opt);
243 kfree_skb(inet_rsk(req)->pktopts);
244 }
245
246 static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
247 {
248 const struct ipv6hdr *rxip6h;
249 struct sk_buff *skb;
250 struct flowi6 fl6;
251 struct net *net = dev_net(skb_dst(rxskb)->dev);
252 struct sock *ctl_sk = net->dccp.v6_ctl_sk;
253 struct dst_entry *dst;
254
255 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
256 return;
257
258 if (!ipv6_unicast_destination(rxskb))
259 return;
260
261 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
262 if (skb == NULL)
263 return;
264
265 rxip6h = ipv6_hdr(rxskb);
266 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
267 &rxip6h->daddr);
268
269 memset(&fl6, 0, sizeof(fl6));
270 fl6.daddr = rxip6h->saddr;
271 fl6.saddr = rxip6h->daddr;
272
273 fl6.flowi6_proto = IPPROTO_DCCP;
274 fl6.flowi6_oif = inet6_iif(rxskb);
275 fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
276 fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
277 security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
278
279 /* sk = NULL, but it is safe for now. RST socket required. */
280 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL);
281 if (!IS_ERR(dst)) {
282 skb_dst_set(skb, dst);
283 ip6_xmit(ctl_sk, skb, &fl6, NULL, 0);
284 DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
285 DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
286 return;
287 }
288
289 kfree_skb(skb);
290 }
291
292 static struct request_sock_ops dccp6_request_sock_ops = {
293 .family = AF_INET6,
294 .obj_size = sizeof(struct dccp6_request_sock),
295 .rtx_syn_ack = dccp_v6_send_response,
296 .send_ack = dccp_reqsk_send_ack,
297 .destructor = dccp_v6_reqsk_destructor,
298 .send_reset = dccp_v6_ctl_send_reset,
299 .syn_ack_timeout = dccp_syn_ack_timeout,
300 };
301
302 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
303 {
304 struct request_sock *req;
305 struct dccp_request_sock *dreq;
306 struct inet_request_sock *ireq;
307 struct ipv6_pinfo *np = inet6_sk(sk);
308 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
309 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
310
311 if (skb->protocol == htons(ETH_P_IP))
312 return dccp_v4_conn_request(sk, skb);
313
314 if (!ipv6_unicast_destination(skb))
315 return 0; /* discard, don't send a reset here */
316
317 if (dccp_bad_service_code(sk, service)) {
318 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
319 goto drop;
320 }
321 /*
322 * There are no SYN attacks on IPv6, yet...
323 */
324 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
325 if (inet_csk_reqsk_queue_is_full(sk))
326 goto drop;
327
328 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
329 goto drop;
330
331 req = inet_reqsk_alloc(&dccp6_request_sock_ops, sk, true);
332 if (req == NULL)
333 goto drop;
334
335 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
336 goto drop_and_free;
337
338 dreq = dccp_rsk(req);
339 if (dccp_parse_options(sk, dreq, skb))
340 goto drop_and_free;
341
342 if (security_inet_conn_request(sk, skb, req))
343 goto drop_and_free;
344
345 ireq = inet_rsk(req);
346 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
347 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
348 ireq->ireq_family = AF_INET6;
349
350 if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
351 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
352 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
353 atomic_inc(&skb->users);
354 ireq->pktopts = skb;
355 }
356 ireq->ir_iif = sk->sk_bound_dev_if;
357
358 /* So that link locals have meaning */
359 if (!sk->sk_bound_dev_if &&
360 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
361 ireq->ir_iif = inet6_iif(skb);
362
363 /*
364 * Step 3: Process LISTEN state
365 *
366 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
367 *
368 * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
369 */
370 dreq->dreq_isr = dcb->dccpd_seq;
371 dreq->dreq_gsr = dreq->dreq_isr;
372 dreq->dreq_iss = dccp_v6_init_sequence(skb);
373 dreq->dreq_gss = dreq->dreq_iss;
374 dreq->dreq_service = service;
375
376 if (dccp_v6_send_response(sk, req))
377 goto drop_and_free;
378
379 inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
380 return 0;
381
382 drop_and_free:
383 reqsk_free(req);
384 drop:
385 __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS);
386 return -1;
387 }
388
389 static struct sock *dccp_v6_request_recv_sock(const struct sock *sk,
390 struct sk_buff *skb,
391 struct request_sock *req,
392 struct dst_entry *dst,
393 struct request_sock *req_unhash,
394 bool *own_req)
395 {
396 struct inet_request_sock *ireq = inet_rsk(req);
397 struct ipv6_pinfo *newnp;
398 const struct ipv6_pinfo *np = inet6_sk(sk);
399 struct ipv6_txoptions *opt;
400 struct inet_sock *newinet;
401 struct dccp6_sock *newdp6;
402 struct sock *newsk;
403
404 if (skb->protocol == htons(ETH_P_IP)) {
405 /*
406 * v6 mapped
407 */
408 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst,
409 req_unhash, own_req);
410 if (newsk == NULL)
411 return NULL;
412
413 newdp6 = (struct dccp6_sock *)newsk;
414 newinet = inet_sk(newsk);
415 newinet->pinet6 = &newdp6->inet6;
416 newnp = inet6_sk(newsk);
417
418 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
419
420 newnp->saddr = newsk->sk_v6_rcv_saddr;
421
422 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
423 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
424 newnp->pktoptions = NULL;
425 newnp->opt = NULL;
426 newnp->mcast_oif = inet6_iif(skb);
427 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
428
429 /*
430 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
431 * here, dccp_create_openreq_child now does this for us, see the comment in
432 * that function for the gory details. -acme
433 */
434
435 /* It is tricky place. Until this moment IPv4 tcp
436 worked with IPv6 icsk.icsk_af_ops.
437 Sync it now.
438 */
439 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
440
441 return newsk;
442 }
443
444
445 if (sk_acceptq_is_full(sk))
446 goto out_overflow;
447
448 if (!dst) {
449 struct flowi6 fl6;
450
451 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_DCCP);
452 if (!dst)
453 goto out;
454 }
455
456 newsk = dccp_create_openreq_child(sk, req, skb);
457 if (newsk == NULL)
458 goto out_nonewsk;
459
460 /*
461 * No need to charge this sock to the relevant IPv6 refcnt debug socks
462 * count here, dccp_create_openreq_child now does this for us, see the
463 * comment in that function for the gory details. -acme
464 */
465
466 ip6_dst_store(newsk, dst, NULL, NULL);
467 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
468 NETIF_F_TSO);
469 newdp6 = (struct dccp6_sock *)newsk;
470 newinet = inet_sk(newsk);
471 newinet->pinet6 = &newdp6->inet6;
472 newnp = inet6_sk(newsk);
473
474 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
475
476 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr;
477 newnp->saddr = ireq->ir_v6_loc_addr;
478 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
479 newsk->sk_bound_dev_if = ireq->ir_iif;
480
481 /* Now IPv6 options...
482
483 First: no IPv4 options.
484 */
485 newinet->inet_opt = NULL;
486
487 /* Clone RX bits */
488 newnp->rxopt.all = np->rxopt.all;
489
490 newnp->pktoptions = NULL;
491 newnp->opt = NULL;
492 newnp->mcast_oif = inet6_iif(skb);
493 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
494
495 /*
496 * Clone native IPv6 options from listening socket (if any)
497 *
498 * Yes, keeping reference count would be much more clever, but we make
499 * one more one thing there: reattach optmem to newsk.
500 */
501 opt = ireq->ipv6_opt;
502 if (!opt)
503 opt = rcu_dereference(np->opt);
504 if (opt) {
505 opt = ipv6_dup_options(newsk, opt);
506 RCU_INIT_POINTER(newnp->opt, opt);
507 }
508 inet_csk(newsk)->icsk_ext_hdr_len = 0;
509 if (opt)
510 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen +
511 opt->opt_flen;
512
513 dccp_sync_mss(newsk, dst_mtu(dst));
514
515 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
516 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
517
518 if (__inet_inherit_port(sk, newsk) < 0) {
519 inet_csk_prepare_forced_close(newsk);
520 dccp_done(newsk);
521 goto out;
522 }
523 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash));
524 /* Clone pktoptions received with SYN, if we own the req */
525 if (*own_req && ireq->pktopts) {
526 newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC);
527 consume_skb(ireq->pktopts);
528 ireq->pktopts = NULL;
529 if (newnp->pktoptions)
530 skb_set_owner_r(newnp->pktoptions, newsk);
531 }
532
533 return newsk;
534
535 out_overflow:
536 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
537 out_nonewsk:
538 dst_release(dst);
539 out:
540 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS);
541 return NULL;
542 }
543
544 /* The socket must have it's spinlock held when we get
545 * here.
546 *
547 * We have a potential double-lock case here, so even when
548 * doing backlog processing we use the BH locking scheme.
549 * This is because we cannot sleep with the original spinlock
550 * held.
551 */
552 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
553 {
554 struct ipv6_pinfo *np = inet6_sk(sk);
555 struct sk_buff *opt_skb = NULL;
556
557 /* Imagine: socket is IPv6. IPv4 packet arrives,
558 goes to IPv4 receive handler and backlogged.
559 From backlog it always goes here. Kerboom...
560 Fortunately, dccp_rcv_established and rcv_established
561 handle them correctly, but it is not case with
562 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
563 */
564
565 if (skb->protocol == htons(ETH_P_IP))
566 return dccp_v4_do_rcv(sk, skb);
567
568 if (sk_filter(sk, skb))
569 goto discard;
570
571 /*
572 * socket locking is here for SMP purposes as backlog rcv is currently
573 * called with bh processing disabled.
574 */
575
576 /* Do Stevens' IPV6_PKTOPTIONS.
577
578 Yes, guys, it is the only place in our code, where we
579 may make it not affecting IPv4.
580 The rest of code is protocol independent,
581 and I do not like idea to uglify IPv4.
582
583 Actually, all the idea behind IPV6_PKTOPTIONS
584 looks not very well thought. For now we latch
585 options, received in the last packet, enqueued
586 by tcp. Feel free to propose better solution.
587 --ANK (980728)
588 */
589 if (np->rxopt.all)
590 /*
591 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
592 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
593 */
594 opt_skb = skb_clone(skb, GFP_ATOMIC);
595
596 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
597 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
598 goto reset;
599 if (opt_skb) {
600 /* XXX This is where we would goto ipv6_pktoptions. */
601 __kfree_skb(opt_skb);
602 }
603 return 0;
604 }
605
606 /*
607 * Step 3: Process LISTEN state
608 * If S.state == LISTEN,
609 * If P.type == Request or P contains a valid Init Cookie option,
610 * (* Must scan the packet's options to check for Init
611 * Cookies. Only Init Cookies are processed here,
612 * however; other options are processed in Step 8. This
613 * scan need only be performed if the endpoint uses Init
614 * Cookies *)
615 * (* Generate a new socket and switch to that socket *)
616 * Set S := new socket for this port pair
617 * S.state = RESPOND
618 * Choose S.ISS (initial seqno) or set from Init Cookies
619 * Initialize S.GAR := S.ISS
620 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
621 * Continue with S.state == RESPOND
622 * (* A Response packet will be generated in Step 11 *)
623 * Otherwise,
624 * Generate Reset(No Connection) unless P.type == Reset
625 * Drop packet and return
626 *
627 * NOTE: the check for the packet types is done in
628 * dccp_rcv_state_process
629 */
630
631 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
632 goto reset;
633 if (opt_skb) {
634 /* XXX This is where we would goto ipv6_pktoptions. */
635 __kfree_skb(opt_skb);
636 }
637 return 0;
638
639 reset:
640 dccp_v6_ctl_send_reset(sk, skb);
641 discard:
642 if (opt_skb != NULL)
643 __kfree_skb(opt_skb);
644 kfree_skb(skb);
645 return 0;
646 }
647
648 static int dccp_v6_rcv(struct sk_buff *skb)
649 {
650 const struct dccp_hdr *dh;
651 bool refcounted;
652 struct sock *sk;
653 int min_cov;
654
655 /* Step 1: Check header basics */
656
657 if (dccp_invalid_packet(skb))
658 goto discard_it;
659
660 /* Step 1: If header checksum is incorrect, drop packet and return. */
661 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
662 &ipv6_hdr(skb)->daddr)) {
663 DCCP_WARN("dropped packet with invalid checksum\n");
664 goto discard_it;
665 }
666
667 dh = dccp_hdr(skb);
668
669 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
670 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
671
672 if (dccp_packet_without_ack(skb))
673 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
674 else
675 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
676
677 lookup:
678 sk = __inet6_lookup_skb(&dccp_hashinfo, skb, __dccp_hdr_len(dh),
679 dh->dccph_sport, dh->dccph_dport,
680 inet6_iif(skb), &refcounted);
681 if (!sk) {
682 dccp_pr_debug("failed to look up flow ID in table and "
683 "get corresponding socket\n");
684 goto no_dccp_socket;
685 }
686
687 /*
688 * Step 2:
689 * ... or S.state == TIMEWAIT,
690 * Generate Reset(No Connection) unless P.type == Reset
691 * Drop packet and return
692 */
693 if (sk->sk_state == DCCP_TIME_WAIT) {
694 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
695 inet_twsk_put(inet_twsk(sk));
696 goto no_dccp_socket;
697 }
698
699 if (sk->sk_state == DCCP_NEW_SYN_RECV) {
700 struct request_sock *req = inet_reqsk(sk);
701 struct sock *nsk;
702
703 sk = req->rsk_listener;
704 if (unlikely(sk->sk_state != DCCP_LISTEN)) {
705 inet_csk_reqsk_queue_drop_and_put(sk, req);
706 goto lookup;
707 }
708 sock_hold(sk);
709 refcounted = true;
710 nsk = dccp_check_req(sk, skb, req);
711 if (!nsk) {
712 reqsk_put(req);
713 goto discard_and_relse;
714 }
715 if (nsk == sk) {
716 reqsk_put(req);
717 } else if (dccp_child_process(sk, nsk, skb)) {
718 dccp_v6_ctl_send_reset(sk, skb);
719 goto discard_and_relse;
720 } else {
721 sock_put(sk);
722 return 0;
723 }
724 }
725 /*
726 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
727 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
728 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
729 */
730 min_cov = dccp_sk(sk)->dccps_pcrlen;
731 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
732 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
733 dh->dccph_cscov, min_cov);
734 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
735 goto discard_and_relse;
736 }
737
738 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
739 goto discard_and_relse;
740
741 return __sk_receive_skb(sk, skb, 1, dh->dccph_doff * 4) ? -1 : 0;
742
743 no_dccp_socket:
744 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
745 goto discard_it;
746 /*
747 * Step 2:
748 * If no socket ...
749 * Generate Reset(No Connection) unless P.type == Reset
750 * Drop packet and return
751 */
752 if (dh->dccph_type != DCCP_PKT_RESET) {
753 DCCP_SKB_CB(skb)->dccpd_reset_code =
754 DCCP_RESET_CODE_NO_CONNECTION;
755 dccp_v6_ctl_send_reset(sk, skb);
756 }
757
758 discard_it:
759 kfree_skb(skb);
760 return 0;
761
762 discard_and_relse:
763 if (refcounted)
764 sock_put(sk);
765 goto discard_it;
766 }
767
768 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
769 int addr_len)
770 {
771 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
772 struct inet_connection_sock *icsk = inet_csk(sk);
773 struct inet_sock *inet = inet_sk(sk);
774 struct ipv6_pinfo *np = inet6_sk(sk);
775 struct dccp_sock *dp = dccp_sk(sk);
776 struct in6_addr *saddr = NULL, *final_p, final;
777 struct ipv6_txoptions *opt;
778 struct flowi6 fl6;
779 struct dst_entry *dst;
780 int addr_type;
781 int err;
782
783 dp->dccps_role = DCCP_ROLE_CLIENT;
784
785 if (addr_len < SIN6_LEN_RFC2133)
786 return -EINVAL;
787
788 if (usin->sin6_family != AF_INET6)
789 return -EAFNOSUPPORT;
790
791 memset(&fl6, 0, sizeof(fl6));
792
793 if (np->sndflow) {
794 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
795 IP6_ECN_flow_init(fl6.flowlabel);
796 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
797 struct ip6_flowlabel *flowlabel;
798 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
799 if (flowlabel == NULL)
800 return -EINVAL;
801 fl6_sock_release(flowlabel);
802 }
803 }
804 /*
805 * connect() to INADDR_ANY means loopback (BSD'ism).
806 */
807 if (ipv6_addr_any(&usin->sin6_addr))
808 usin->sin6_addr.s6_addr[15] = 1;
809
810 addr_type = ipv6_addr_type(&usin->sin6_addr);
811
812 if (addr_type & IPV6_ADDR_MULTICAST)
813 return -ENETUNREACH;
814
815 if (addr_type & IPV6_ADDR_LINKLOCAL) {
816 if (addr_len >= sizeof(struct sockaddr_in6) &&
817 usin->sin6_scope_id) {
818 /* If interface is set while binding, indices
819 * must coincide.
820 */
821 if (sk->sk_bound_dev_if &&
822 sk->sk_bound_dev_if != usin->sin6_scope_id)
823 return -EINVAL;
824
825 sk->sk_bound_dev_if = usin->sin6_scope_id;
826 }
827
828 /* Connect to link-local address requires an interface */
829 if (!sk->sk_bound_dev_if)
830 return -EINVAL;
831 }
832
833 sk->sk_v6_daddr = usin->sin6_addr;
834 np->flow_label = fl6.flowlabel;
835
836 /*
837 * DCCP over IPv4
838 */
839 if (addr_type == IPV6_ADDR_MAPPED) {
840 u32 exthdrlen = icsk->icsk_ext_hdr_len;
841 struct sockaddr_in sin;
842
843 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
844
845 if (__ipv6_only_sock(sk))
846 return -ENETUNREACH;
847
848 sin.sin_family = AF_INET;
849 sin.sin_port = usin->sin6_port;
850 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
851
852 icsk->icsk_af_ops = &dccp_ipv6_mapped;
853 sk->sk_backlog_rcv = dccp_v4_do_rcv;
854
855 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
856 if (err) {
857 icsk->icsk_ext_hdr_len = exthdrlen;
858 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
859 sk->sk_backlog_rcv = dccp_v6_do_rcv;
860 goto failure;
861 }
862 np->saddr = sk->sk_v6_rcv_saddr;
863 return err;
864 }
865
866 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr))
867 saddr = &sk->sk_v6_rcv_saddr;
868
869 fl6.flowi6_proto = IPPROTO_DCCP;
870 fl6.daddr = sk->sk_v6_daddr;
871 fl6.saddr = saddr ? *saddr : np->saddr;
872 fl6.flowi6_oif = sk->sk_bound_dev_if;
873 fl6.fl6_dport = usin->sin6_port;
874 fl6.fl6_sport = inet->inet_sport;
875 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
876
877 opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
878 final_p = fl6_update_dst(&fl6, opt, &final);
879
880 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
881 if (IS_ERR(dst)) {
882 err = PTR_ERR(dst);
883 goto failure;
884 }
885
886 if (saddr == NULL) {
887 saddr = &fl6.saddr;
888 sk->sk_v6_rcv_saddr = *saddr;
889 }
890
891 /* set the source address */
892 np->saddr = *saddr;
893 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
894
895 ip6_dst_store(sk, dst, NULL, NULL);
896
897 icsk->icsk_ext_hdr_len = 0;
898 if (opt)
899 icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
900
901 inet->inet_dport = usin->sin6_port;
902
903 dccp_set_state(sk, DCCP_REQUESTING);
904 err = inet6_hash_connect(&dccp_death_row, sk);
905 if (err)
906 goto late_failure;
907
908 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
909 sk->sk_v6_daddr.s6_addr32,
910 inet->inet_sport,
911 inet->inet_dport);
912 err = dccp_connect(sk);
913 if (err)
914 goto late_failure;
915
916 return 0;
917
918 late_failure:
919 dccp_set_state(sk, DCCP_CLOSED);
920 __sk_dst_reset(sk);
921 failure:
922 inet->inet_dport = 0;
923 sk->sk_route_caps = 0;
924 return err;
925 }
926
927 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
928 .queue_xmit = inet6_csk_xmit,
929 .send_check = dccp_v6_send_check,
930 .rebuild_header = inet6_sk_rebuild_header,
931 .conn_request = dccp_v6_conn_request,
932 .syn_recv_sock = dccp_v6_request_recv_sock,
933 .net_header_len = sizeof(struct ipv6hdr),
934 .setsockopt = ipv6_setsockopt,
935 .getsockopt = ipv6_getsockopt,
936 .addr2sockaddr = inet6_csk_addr2sockaddr,
937 .sockaddr_len = sizeof(struct sockaddr_in6),
938 .bind_conflict = inet6_csk_bind_conflict,
939 #ifdef CONFIG_COMPAT
940 .compat_setsockopt = compat_ipv6_setsockopt,
941 .compat_getsockopt = compat_ipv6_getsockopt,
942 #endif
943 };
944
945 /*
946 * DCCP over IPv4 via INET6 API
947 */
948 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
949 .queue_xmit = ip_queue_xmit,
950 .send_check = dccp_v4_send_check,
951 .rebuild_header = inet_sk_rebuild_header,
952 .conn_request = dccp_v6_conn_request,
953 .syn_recv_sock = dccp_v6_request_recv_sock,
954 .net_header_len = sizeof(struct iphdr),
955 .setsockopt = ipv6_setsockopt,
956 .getsockopt = ipv6_getsockopt,
957 .addr2sockaddr = inet6_csk_addr2sockaddr,
958 .sockaddr_len = sizeof(struct sockaddr_in6),
959 #ifdef CONFIG_COMPAT
960 .compat_setsockopt = compat_ipv6_setsockopt,
961 .compat_getsockopt = compat_ipv6_getsockopt,
962 #endif
963 };
964
965 /* NOTE: A lot of things set to zero explicitly by call to
966 * sk_alloc() so need not be done here.
967 */
968 static int dccp_v6_init_sock(struct sock *sk)
969 {
970 static __u8 dccp_v6_ctl_sock_initialized;
971 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
972
973 if (err == 0) {
974 if (unlikely(!dccp_v6_ctl_sock_initialized))
975 dccp_v6_ctl_sock_initialized = 1;
976 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
977 }
978
979 return err;
980 }
981
982 static void dccp_v6_destroy_sock(struct sock *sk)
983 {
984 dccp_destroy_sock(sk);
985 inet6_destroy_sock(sk);
986 }
987
988 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
989 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
990 };
991
992 static struct proto dccp_v6_prot = {
993 .name = "DCCPv6",
994 .owner = THIS_MODULE,
995 .close = dccp_close,
996 .connect = dccp_v6_connect,
997 .disconnect = dccp_disconnect,
998 .ioctl = dccp_ioctl,
999 .init = dccp_v6_init_sock,
1000 .setsockopt = dccp_setsockopt,
1001 .getsockopt = dccp_getsockopt,
1002 .sendmsg = dccp_sendmsg,
1003 .recvmsg = dccp_recvmsg,
1004 .backlog_rcv = dccp_v6_do_rcv,
1005 .hash = inet6_hash,
1006 .unhash = inet_unhash,
1007 .accept = inet_csk_accept,
1008 .get_port = inet_csk_get_port,
1009 .shutdown = dccp_shutdown,
1010 .destroy = dccp_v6_destroy_sock,
1011 .orphan_count = &dccp_orphan_count,
1012 .max_header = MAX_DCCP_HEADER,
1013 .obj_size = sizeof(struct dccp6_sock),
1014 .slab_flags = SLAB_DESTROY_BY_RCU,
1015 .rsk_prot = &dccp6_request_sock_ops,
1016 .twsk_prot = &dccp6_timewait_sock_ops,
1017 .h.hashinfo = &dccp_hashinfo,
1018 #ifdef CONFIG_COMPAT
1019 .compat_setsockopt = compat_dccp_setsockopt,
1020 .compat_getsockopt = compat_dccp_getsockopt,
1021 #endif
1022 };
1023
1024 static const struct inet6_protocol dccp_v6_protocol = {
1025 .handler = dccp_v6_rcv,
1026 .err_handler = dccp_v6_err,
1027 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1028 };
1029
1030 static const struct proto_ops inet6_dccp_ops = {
1031 .family = PF_INET6,
1032 .owner = THIS_MODULE,
1033 .release = inet6_release,
1034 .bind = inet6_bind,
1035 .connect = inet_stream_connect,
1036 .socketpair = sock_no_socketpair,
1037 .accept = inet_accept,
1038 .getname = inet6_getname,
1039 .poll = dccp_poll,
1040 .ioctl = inet6_ioctl,
1041 .listen = inet_dccp_listen,
1042 .shutdown = inet_shutdown,
1043 .setsockopt = sock_common_setsockopt,
1044 .getsockopt = sock_common_getsockopt,
1045 .sendmsg = inet_sendmsg,
1046 .recvmsg = sock_common_recvmsg,
1047 .mmap = sock_no_mmap,
1048 .sendpage = sock_no_sendpage,
1049 #ifdef CONFIG_COMPAT
1050 .compat_setsockopt = compat_sock_common_setsockopt,
1051 .compat_getsockopt = compat_sock_common_getsockopt,
1052 #endif
1053 };
1054
1055 static struct inet_protosw dccp_v6_protosw = {
1056 .type = SOCK_DCCP,
1057 .protocol = IPPROTO_DCCP,
1058 .prot = &dccp_v6_prot,
1059 .ops = &inet6_dccp_ops,
1060 .flags = INET_PROTOSW_ICSK,
1061 };
1062
1063 static int __net_init dccp_v6_init_net(struct net *net)
1064 {
1065 if (dccp_hashinfo.bhash == NULL)
1066 return -ESOCKTNOSUPPORT;
1067
1068 return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6,
1069 SOCK_DCCP, IPPROTO_DCCP, net);
1070 }
1071
1072 static void __net_exit dccp_v6_exit_net(struct net *net)
1073 {
1074 inet_ctl_sock_destroy(net->dccp.v6_ctl_sk);
1075 }
1076
1077 static struct pernet_operations dccp_v6_ops = {
1078 .init = dccp_v6_init_net,
1079 .exit = dccp_v6_exit_net,
1080 };
1081
1082 static int __init dccp_v6_init(void)
1083 {
1084 int err = proto_register(&dccp_v6_prot, 1);
1085
1086 if (err != 0)
1087 goto out;
1088
1089 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1090 if (err != 0)
1091 goto out_unregister_proto;
1092
1093 inet6_register_protosw(&dccp_v6_protosw);
1094
1095 err = register_pernet_subsys(&dccp_v6_ops);
1096 if (err != 0)
1097 goto out_destroy_ctl_sock;
1098 out:
1099 return err;
1100
1101 out_destroy_ctl_sock:
1102 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1103 inet6_unregister_protosw(&dccp_v6_protosw);
1104 out_unregister_proto:
1105 proto_unregister(&dccp_v6_prot);
1106 goto out;
1107 }
1108
1109 static void __exit dccp_v6_exit(void)
1110 {
1111 unregister_pernet_subsys(&dccp_v6_ops);
1112 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1113 inet6_unregister_protosw(&dccp_v6_protosw);
1114 proto_unregister(&dccp_v6_prot);
1115 }
1116
1117 module_init(dccp_v6_init);
1118 module_exit(dccp_v6_exit);
1119
1120 /*
1121 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1122 * values directly, Also cover the case where the protocol is not specified,
1123 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1124 */
1125 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1126 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1127 MODULE_LICENSE("GPL");
1128 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1129 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");
Linux with added FPC-III support