Bluetooth: Gracefully response to enabling LE on LE only devices
[linux/fpc-iii.git] / net / dccp / ipv6.c
blob5166b0043f95171f3d761274201ec7da0558fa02
1 /*
2 * DCCP over IPv6
3 * Linux INET6 implementation
5 * Based on net/dccp6/ipv6.c
7 * Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
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.
15 #include <linux/module.h>
16 #include <linux/random.h>
17 #include <linux/slab.h>
18 #include <linux/xfrm.h>
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>
34 #include "dccp.h"
35 #include "ipv6.h"
36 #include "feat.h"
38 /* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */
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;
43 static void dccp_v6_hash(struct sock *sk)
45 if (sk->sk_state != DCCP_CLOSED) {
46 if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) {
47 inet_hash(sk);
48 return;
50 local_bh_disable();
51 __inet6_hash(sk, NULL);
52 local_bh_enable();
56 /* add pseudo-header to DCCP checksum stored in skb->csum */
57 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
58 const struct in6_addr *saddr,
59 const struct in6_addr *daddr)
61 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
64 static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
66 struct ipv6_pinfo *np = inet6_sk(sk);
67 struct dccp_hdr *dh = dccp_hdr(skb);
69 dccp_csum_outgoing(skb);
70 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr);
73 static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb)
75 return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
76 ipv6_hdr(skb)->saddr.s6_addr32,
77 dccp_hdr(skb)->dccph_dport,
78 dccp_hdr(skb)->dccph_sport );
82 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
83 u8 type, u8 code, int offset, __be32 info)
85 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
86 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
87 struct dccp_sock *dp;
88 struct ipv6_pinfo *np;
89 struct sock *sk;
90 int err;
91 __u64 seq;
92 struct net *net = dev_net(skb->dev);
94 if (skb->len < offset + sizeof(*dh) ||
95 skb->len < offset + __dccp_basic_hdr_len(dh)) {
96 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
97 ICMP6_MIB_INERRORS);
98 return;
101 sk = inet6_lookup(net, &dccp_hashinfo,
102 &hdr->daddr, dh->dccph_dport,
103 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
105 if (sk == NULL) {
106 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
107 ICMP6_MIB_INERRORS);
108 return;
111 if (sk->sk_state == DCCP_TIME_WAIT) {
112 inet_twsk_put(inet_twsk(sk));
113 return;
116 bh_lock_sock(sk);
117 if (sock_owned_by_user(sk))
118 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
120 if (sk->sk_state == DCCP_CLOSED)
121 goto out;
123 dp = dccp_sk(sk);
124 seq = dccp_hdr_seq(dh);
125 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
126 !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
127 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
128 goto out;
131 np = inet6_sk(sk);
133 if (type == NDISC_REDIRECT) {
134 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
136 if (dst)
137 dst->ops->redirect(dst, sk, skb);
138 goto out;
141 if (type == ICMPV6_PKT_TOOBIG) {
142 struct dst_entry *dst = NULL;
144 if (!ip6_sk_accept_pmtu(sk))
145 goto out;
147 if (sock_owned_by_user(sk))
148 goto out;
149 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
150 goto out;
152 dst = inet6_csk_update_pmtu(sk, ntohl(info));
153 if (!dst)
154 goto out;
156 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
157 dccp_sync_mss(sk, dst_mtu(dst));
158 goto out;
161 icmpv6_err_convert(type, code, &err);
163 /* Might be for an request_sock */
164 switch (sk->sk_state) {
165 struct request_sock *req, **prev;
166 case DCCP_LISTEN:
167 if (sock_owned_by_user(sk))
168 goto out;
170 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
171 &hdr->daddr, &hdr->saddr,
172 inet6_iif(skb));
173 if (req == NULL)
174 goto out;
177 * ICMPs are not backlogged, hence we cannot get an established
178 * socket here.
180 WARN_ON(req->sk != NULL);
182 if (!between48(seq, dccp_rsk(req)->dreq_iss,
183 dccp_rsk(req)->dreq_gss)) {
184 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
185 goto out;
188 inet_csk_reqsk_queue_drop(sk, req, prev);
189 goto out;
191 case DCCP_REQUESTING:
192 case DCCP_RESPOND: /* Cannot happen.
193 It can, it SYNs are crossed. --ANK */
194 if (!sock_owned_by_user(sk)) {
195 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
196 sk->sk_err = err;
198 * Wake people up to see the error
199 * (see connect in sock.c)
201 sk->sk_error_report(sk);
202 dccp_done(sk);
203 } else
204 sk->sk_err_soft = err;
205 goto out;
208 if (!sock_owned_by_user(sk) && np->recverr) {
209 sk->sk_err = err;
210 sk->sk_error_report(sk);
211 } else
212 sk->sk_err_soft = err;
214 out:
215 bh_unlock_sock(sk);
216 sock_put(sk);
220 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req)
222 struct inet_request_sock *ireq = inet_rsk(req);
223 struct ipv6_pinfo *np = inet6_sk(sk);
224 struct sk_buff *skb;
225 struct in6_addr *final_p, final;
226 struct flowi6 fl6;
227 int err = -1;
228 struct dst_entry *dst;
230 memset(&fl6, 0, sizeof(fl6));
231 fl6.flowi6_proto = IPPROTO_DCCP;
232 fl6.daddr = ireq->ir_v6_rmt_addr;
233 fl6.saddr = ireq->ir_v6_loc_addr;
234 fl6.flowlabel = 0;
235 fl6.flowi6_oif = ireq->ir_iif;
236 fl6.fl6_dport = ireq->ir_rmt_port;
237 fl6.fl6_sport = htons(ireq->ir_num);
238 security_req_classify_flow(req, flowi6_to_flowi(&fl6));
241 final_p = fl6_update_dst(&fl6, np->opt, &final);
243 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
244 if (IS_ERR(dst)) {
245 err = PTR_ERR(dst);
246 dst = NULL;
247 goto done;
250 skb = dccp_make_response(sk, dst, req);
251 if (skb != NULL) {
252 struct dccp_hdr *dh = dccp_hdr(skb);
254 dh->dccph_checksum = dccp_v6_csum_finish(skb,
255 &ireq->ir_v6_loc_addr,
256 &ireq->ir_v6_rmt_addr);
257 fl6.daddr = ireq->ir_v6_rmt_addr;
258 err = ip6_xmit(sk, skb, &fl6, np->opt, np->tclass);
259 err = net_xmit_eval(err);
262 done:
263 dst_release(dst);
264 return err;
267 static void dccp_v6_reqsk_destructor(struct request_sock *req)
269 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
270 kfree_skb(inet_rsk(req)->pktopts);
273 static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
275 const struct ipv6hdr *rxip6h;
276 struct sk_buff *skb;
277 struct flowi6 fl6;
278 struct net *net = dev_net(skb_dst(rxskb)->dev);
279 struct sock *ctl_sk = net->dccp.v6_ctl_sk;
280 struct dst_entry *dst;
282 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
283 return;
285 if (!ipv6_unicast_destination(rxskb))
286 return;
288 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
289 if (skb == NULL)
290 return;
292 rxip6h = ipv6_hdr(rxskb);
293 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
294 &rxip6h->daddr);
296 memset(&fl6, 0, sizeof(fl6));
297 fl6.daddr = rxip6h->saddr;
298 fl6.saddr = rxip6h->daddr;
300 fl6.flowi6_proto = IPPROTO_DCCP;
301 fl6.flowi6_oif = inet6_iif(rxskb);
302 fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
303 fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
304 security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
306 /* sk = NULL, but it is safe for now. RST socket required. */
307 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL);
308 if (!IS_ERR(dst)) {
309 skb_dst_set(skb, dst);
310 ip6_xmit(ctl_sk, skb, &fl6, NULL, 0);
311 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
312 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
313 return;
316 kfree_skb(skb);
319 static struct request_sock_ops dccp6_request_sock_ops = {
320 .family = AF_INET6,
321 .obj_size = sizeof(struct dccp6_request_sock),
322 .rtx_syn_ack = dccp_v6_send_response,
323 .send_ack = dccp_reqsk_send_ack,
324 .destructor = dccp_v6_reqsk_destructor,
325 .send_reset = dccp_v6_ctl_send_reset,
326 .syn_ack_timeout = dccp_syn_ack_timeout,
329 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
331 const struct dccp_hdr *dh = dccp_hdr(skb);
332 const struct ipv6hdr *iph = ipv6_hdr(skb);
333 struct sock *nsk;
334 struct request_sock **prev;
335 /* Find possible connection requests. */
336 struct request_sock *req = inet6_csk_search_req(sk, &prev,
337 dh->dccph_sport,
338 &iph->saddr,
339 &iph->daddr,
340 inet6_iif(skb));
341 if (req != NULL)
342 return dccp_check_req(sk, skb, req, prev);
344 nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo,
345 &iph->saddr, dh->dccph_sport,
346 &iph->daddr, ntohs(dh->dccph_dport),
347 inet6_iif(skb));
348 if (nsk != NULL) {
349 if (nsk->sk_state != DCCP_TIME_WAIT) {
350 bh_lock_sock(nsk);
351 return nsk;
353 inet_twsk_put(inet_twsk(nsk));
354 return NULL;
357 return sk;
360 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
362 struct request_sock *req;
363 struct dccp_request_sock *dreq;
364 struct inet_request_sock *ireq;
365 struct ipv6_pinfo *np = inet6_sk(sk);
366 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
367 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
369 if (skb->protocol == htons(ETH_P_IP))
370 return dccp_v4_conn_request(sk, skb);
372 if (!ipv6_unicast_destination(skb))
373 return 0; /* discard, don't send a reset here */
375 if (dccp_bad_service_code(sk, service)) {
376 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
377 goto drop;
380 * There are no SYN attacks on IPv6, yet...
382 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
383 if (inet_csk_reqsk_queue_is_full(sk))
384 goto drop;
386 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
387 goto drop;
389 req = inet_reqsk_alloc(&dccp6_request_sock_ops);
390 if (req == NULL)
391 goto drop;
393 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
394 goto drop_and_free;
396 dreq = dccp_rsk(req);
397 if (dccp_parse_options(sk, dreq, skb))
398 goto drop_and_free;
400 if (security_inet_conn_request(sk, skb, req))
401 goto drop_and_free;
403 ireq = inet_rsk(req);
404 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
405 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
406 write_pnet(&ireq->ireq_net, sock_net(sk));
407 ireq->ireq_family = AF_INET6;
409 if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
410 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
411 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
412 atomic_inc(&skb->users);
413 ireq->pktopts = skb;
415 ireq->ir_iif = sk->sk_bound_dev_if;
417 /* So that link locals have meaning */
418 if (!sk->sk_bound_dev_if &&
419 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
420 ireq->ir_iif = inet6_iif(skb);
423 * Step 3: Process LISTEN state
425 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
427 * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
429 dreq->dreq_isr = dcb->dccpd_seq;
430 dreq->dreq_gsr = dreq->dreq_isr;
431 dreq->dreq_iss = dccp_v6_init_sequence(skb);
432 dreq->dreq_gss = dreq->dreq_iss;
433 dreq->dreq_service = service;
435 if (dccp_v6_send_response(sk, req))
436 goto drop_and_free;
438 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
439 return 0;
441 drop_and_free:
442 reqsk_free(req);
443 drop:
444 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
445 return -1;
448 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
449 struct sk_buff *skb,
450 struct request_sock *req,
451 struct dst_entry *dst)
453 struct inet_request_sock *ireq = inet_rsk(req);
454 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
455 struct inet_sock *newinet;
456 struct dccp6_sock *newdp6;
457 struct sock *newsk;
459 if (skb->protocol == htons(ETH_P_IP)) {
461 * v6 mapped
463 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
464 if (newsk == NULL)
465 return NULL;
467 newdp6 = (struct dccp6_sock *)newsk;
468 newinet = inet_sk(newsk);
469 newinet->pinet6 = &newdp6->inet6;
470 newnp = inet6_sk(newsk);
472 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
474 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newsk->sk_v6_daddr);
476 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
478 newsk->sk_v6_rcv_saddr = newnp->saddr;
480 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
481 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
482 newnp->pktoptions = NULL;
483 newnp->opt = NULL;
484 newnp->mcast_oif = inet6_iif(skb);
485 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
488 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
489 * here, dccp_create_openreq_child now does this for us, see the comment in
490 * that function for the gory details. -acme
493 /* It is tricky place. Until this moment IPv4 tcp
494 worked with IPv6 icsk.icsk_af_ops.
495 Sync it now.
497 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
499 return newsk;
503 if (sk_acceptq_is_full(sk))
504 goto out_overflow;
506 if (dst == NULL) {
507 struct in6_addr *final_p, final;
508 struct flowi6 fl6;
510 memset(&fl6, 0, sizeof(fl6));
511 fl6.flowi6_proto = IPPROTO_DCCP;
512 fl6.daddr = ireq->ir_v6_rmt_addr;
513 final_p = fl6_update_dst(&fl6, np->opt, &final);
514 fl6.saddr = ireq->ir_v6_loc_addr;
515 fl6.flowi6_oif = sk->sk_bound_dev_if;
516 fl6.fl6_dport = ireq->ir_rmt_port;
517 fl6.fl6_sport = htons(ireq->ir_num);
518 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
520 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
521 if (IS_ERR(dst))
522 goto out;
525 newsk = dccp_create_openreq_child(sk, req, skb);
526 if (newsk == NULL)
527 goto out_nonewsk;
530 * No need to charge this sock to the relevant IPv6 refcnt debug socks
531 * count here, dccp_create_openreq_child now does this for us, see the
532 * comment in that function for the gory details. -acme
535 __ip6_dst_store(newsk, dst, NULL, NULL);
536 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
537 NETIF_F_TSO);
538 newdp6 = (struct dccp6_sock *)newsk;
539 newinet = inet_sk(newsk);
540 newinet->pinet6 = &newdp6->inet6;
541 newnp = inet6_sk(newsk);
543 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
545 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr;
546 newnp->saddr = ireq->ir_v6_loc_addr;
547 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
548 newsk->sk_bound_dev_if = ireq->ir_iif;
550 /* Now IPv6 options...
552 First: no IPv4 options.
554 newinet->inet_opt = NULL;
556 /* Clone RX bits */
557 newnp->rxopt.all = np->rxopt.all;
559 /* Clone pktoptions received with SYN */
560 newnp->pktoptions = NULL;
561 if (ireq->pktopts != NULL) {
562 newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC);
563 consume_skb(ireq->pktopts);
564 ireq->pktopts = NULL;
565 if (newnp->pktoptions)
566 skb_set_owner_r(newnp->pktoptions, newsk);
568 newnp->opt = NULL;
569 newnp->mcast_oif = inet6_iif(skb);
570 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
573 * Clone native IPv6 options from listening socket (if any)
575 * Yes, keeping reference count would be much more clever, but we make
576 * one more one thing there: reattach optmem to newsk.
578 if (np->opt != NULL)
579 newnp->opt = ipv6_dup_options(newsk, np->opt);
581 inet_csk(newsk)->icsk_ext_hdr_len = 0;
582 if (newnp->opt != NULL)
583 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
584 newnp->opt->opt_flen);
586 dccp_sync_mss(newsk, dst_mtu(dst));
588 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
589 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
591 if (__inet_inherit_port(sk, newsk) < 0) {
592 inet_csk_prepare_forced_close(newsk);
593 dccp_done(newsk);
594 goto out;
596 __inet6_hash(newsk, NULL);
598 return newsk;
600 out_overflow:
601 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
602 out_nonewsk:
603 dst_release(dst);
604 out:
605 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
606 return NULL;
609 /* The socket must have it's spinlock held when we get
610 * here.
612 * We have a potential double-lock case here, so even when
613 * doing backlog processing we use the BH locking scheme.
614 * This is because we cannot sleep with the original spinlock
615 * held.
617 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
619 struct ipv6_pinfo *np = inet6_sk(sk);
620 struct sk_buff *opt_skb = NULL;
622 /* Imagine: socket is IPv6. IPv4 packet arrives,
623 goes to IPv4 receive handler and backlogged.
624 From backlog it always goes here. Kerboom...
625 Fortunately, dccp_rcv_established and rcv_established
626 handle them correctly, but it is not case with
627 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
630 if (skb->protocol == htons(ETH_P_IP))
631 return dccp_v4_do_rcv(sk, skb);
633 if (sk_filter(sk, skb))
634 goto discard;
637 * socket locking is here for SMP purposes as backlog rcv is currently
638 * called with bh processing disabled.
641 /* Do Stevens' IPV6_PKTOPTIONS.
643 Yes, guys, it is the only place in our code, where we
644 may make it not affecting IPv4.
645 The rest of code is protocol independent,
646 and I do not like idea to uglify IPv4.
648 Actually, all the idea behind IPV6_PKTOPTIONS
649 looks not very well thought. For now we latch
650 options, received in the last packet, enqueued
651 by tcp. Feel free to propose better solution.
652 --ANK (980728)
654 if (np->rxopt.all)
656 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
657 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
659 opt_skb = skb_clone(skb, GFP_ATOMIC);
661 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
662 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
663 goto reset;
664 if (opt_skb) {
665 /* XXX This is where we would goto ipv6_pktoptions. */
666 __kfree_skb(opt_skb);
668 return 0;
672 * Step 3: Process LISTEN state
673 * If S.state == LISTEN,
674 * If P.type == Request or P contains a valid Init Cookie option,
675 * (* Must scan the packet's options to check for Init
676 * Cookies. Only Init Cookies are processed here,
677 * however; other options are processed in Step 8. This
678 * scan need only be performed if the endpoint uses Init
679 * Cookies *)
680 * (* Generate a new socket and switch to that socket *)
681 * Set S := new socket for this port pair
682 * S.state = RESPOND
683 * Choose S.ISS (initial seqno) or set from Init Cookies
684 * Initialize S.GAR := S.ISS
685 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
686 * Continue with S.state == RESPOND
687 * (* A Response packet will be generated in Step 11 *)
688 * Otherwise,
689 * Generate Reset(No Connection) unless P.type == Reset
690 * Drop packet and return
692 * NOTE: the check for the packet types is done in
693 * dccp_rcv_state_process
695 if (sk->sk_state == DCCP_LISTEN) {
696 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
698 if (nsk == NULL)
699 goto discard;
701 * Queue it on the new socket if the new socket is active,
702 * otherwise we just shortcircuit this and continue with
703 * the new socket..
705 if (nsk != sk) {
706 if (dccp_child_process(sk, nsk, skb))
707 goto reset;
708 if (opt_skb != NULL)
709 __kfree_skb(opt_skb);
710 return 0;
714 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
715 goto reset;
716 if (opt_skb) {
717 /* XXX This is where we would goto ipv6_pktoptions. */
718 __kfree_skb(opt_skb);
720 return 0;
722 reset:
723 dccp_v6_ctl_send_reset(sk, skb);
724 discard:
725 if (opt_skb != NULL)
726 __kfree_skb(opt_skb);
727 kfree_skb(skb);
728 return 0;
731 static int dccp_v6_rcv(struct sk_buff *skb)
733 const struct dccp_hdr *dh;
734 struct sock *sk;
735 int min_cov;
737 /* Step 1: Check header basics */
739 if (dccp_invalid_packet(skb))
740 goto discard_it;
742 /* Step 1: If header checksum is incorrect, drop packet and return. */
743 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
744 &ipv6_hdr(skb)->daddr)) {
745 DCCP_WARN("dropped packet with invalid checksum\n");
746 goto discard_it;
749 dh = dccp_hdr(skb);
751 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
752 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
754 if (dccp_packet_without_ack(skb))
755 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
756 else
757 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
759 /* Step 2:
760 * Look up flow ID in table and get corresponding socket */
761 sk = __inet6_lookup_skb(&dccp_hashinfo, skb,
762 dh->dccph_sport, dh->dccph_dport,
763 inet6_iif(skb));
765 * Step 2:
766 * If no socket ...
768 if (sk == NULL) {
769 dccp_pr_debug("failed to look up flow ID in table and "
770 "get corresponding socket\n");
771 goto no_dccp_socket;
775 * Step 2:
776 * ... or S.state == TIMEWAIT,
777 * Generate Reset(No Connection) unless P.type == Reset
778 * Drop packet and return
780 if (sk->sk_state == DCCP_TIME_WAIT) {
781 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
782 inet_twsk_put(inet_twsk(sk));
783 goto no_dccp_socket;
787 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
788 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
789 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
791 min_cov = dccp_sk(sk)->dccps_pcrlen;
792 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
793 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
794 dh->dccph_cscov, min_cov);
795 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
796 goto discard_and_relse;
799 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
800 goto discard_and_relse;
802 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
804 no_dccp_socket:
805 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
806 goto discard_it;
808 * Step 2:
809 * If no socket ...
810 * Generate Reset(No Connection) unless P.type == Reset
811 * Drop packet and return
813 if (dh->dccph_type != DCCP_PKT_RESET) {
814 DCCP_SKB_CB(skb)->dccpd_reset_code =
815 DCCP_RESET_CODE_NO_CONNECTION;
816 dccp_v6_ctl_send_reset(sk, skb);
819 discard_it:
820 kfree_skb(skb);
821 return 0;
823 discard_and_relse:
824 sock_put(sk);
825 goto discard_it;
828 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
829 int addr_len)
831 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
832 struct inet_connection_sock *icsk = inet_csk(sk);
833 struct inet_sock *inet = inet_sk(sk);
834 struct ipv6_pinfo *np = inet6_sk(sk);
835 struct dccp_sock *dp = dccp_sk(sk);
836 struct in6_addr *saddr = NULL, *final_p, final;
837 struct flowi6 fl6;
838 struct dst_entry *dst;
839 int addr_type;
840 int err;
842 dp->dccps_role = DCCP_ROLE_CLIENT;
844 if (addr_len < SIN6_LEN_RFC2133)
845 return -EINVAL;
847 if (usin->sin6_family != AF_INET6)
848 return -EAFNOSUPPORT;
850 memset(&fl6, 0, sizeof(fl6));
852 if (np->sndflow) {
853 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
854 IP6_ECN_flow_init(fl6.flowlabel);
855 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
856 struct ip6_flowlabel *flowlabel;
857 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
858 if (flowlabel == NULL)
859 return -EINVAL;
860 fl6_sock_release(flowlabel);
864 * connect() to INADDR_ANY means loopback (BSD'ism).
866 if (ipv6_addr_any(&usin->sin6_addr))
867 usin->sin6_addr.s6_addr[15] = 1;
869 addr_type = ipv6_addr_type(&usin->sin6_addr);
871 if (addr_type & IPV6_ADDR_MULTICAST)
872 return -ENETUNREACH;
874 if (addr_type & IPV6_ADDR_LINKLOCAL) {
875 if (addr_len >= sizeof(struct sockaddr_in6) &&
876 usin->sin6_scope_id) {
877 /* If interface is set while binding, indices
878 * must coincide.
880 if (sk->sk_bound_dev_if &&
881 sk->sk_bound_dev_if != usin->sin6_scope_id)
882 return -EINVAL;
884 sk->sk_bound_dev_if = usin->sin6_scope_id;
887 /* Connect to link-local address requires an interface */
888 if (!sk->sk_bound_dev_if)
889 return -EINVAL;
892 sk->sk_v6_daddr = usin->sin6_addr;
893 np->flow_label = fl6.flowlabel;
896 * DCCP over IPv4
898 if (addr_type == IPV6_ADDR_MAPPED) {
899 u32 exthdrlen = icsk->icsk_ext_hdr_len;
900 struct sockaddr_in sin;
902 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
904 if (__ipv6_only_sock(sk))
905 return -ENETUNREACH;
907 sin.sin_family = AF_INET;
908 sin.sin_port = usin->sin6_port;
909 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
911 icsk->icsk_af_ops = &dccp_ipv6_mapped;
912 sk->sk_backlog_rcv = dccp_v4_do_rcv;
914 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
915 if (err) {
916 icsk->icsk_ext_hdr_len = exthdrlen;
917 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
918 sk->sk_backlog_rcv = dccp_v6_do_rcv;
919 goto failure;
921 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
922 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &sk->sk_v6_rcv_saddr);
924 return err;
927 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr))
928 saddr = &sk->sk_v6_rcv_saddr;
930 fl6.flowi6_proto = IPPROTO_DCCP;
931 fl6.daddr = sk->sk_v6_daddr;
932 fl6.saddr = saddr ? *saddr : np->saddr;
933 fl6.flowi6_oif = sk->sk_bound_dev_if;
934 fl6.fl6_dport = usin->sin6_port;
935 fl6.fl6_sport = inet->inet_sport;
936 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
938 final_p = fl6_update_dst(&fl6, np->opt, &final);
940 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
941 if (IS_ERR(dst)) {
942 err = PTR_ERR(dst);
943 goto failure;
946 if (saddr == NULL) {
947 saddr = &fl6.saddr;
948 sk->sk_v6_rcv_saddr = *saddr;
951 /* set the source address */
952 np->saddr = *saddr;
953 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
955 __ip6_dst_store(sk, dst, NULL, NULL);
957 icsk->icsk_ext_hdr_len = 0;
958 if (np->opt != NULL)
959 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
960 np->opt->opt_nflen);
962 inet->inet_dport = usin->sin6_port;
964 dccp_set_state(sk, DCCP_REQUESTING);
965 err = inet6_hash_connect(&dccp_death_row, sk);
966 if (err)
967 goto late_failure;
969 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
970 sk->sk_v6_daddr.s6_addr32,
971 inet->inet_sport,
972 inet->inet_dport);
973 err = dccp_connect(sk);
974 if (err)
975 goto late_failure;
977 return 0;
979 late_failure:
980 dccp_set_state(sk, DCCP_CLOSED);
981 __sk_dst_reset(sk);
982 failure:
983 inet->inet_dport = 0;
984 sk->sk_route_caps = 0;
985 return err;
988 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
989 .queue_xmit = inet6_csk_xmit,
990 .send_check = dccp_v6_send_check,
991 .rebuild_header = inet6_sk_rebuild_header,
992 .conn_request = dccp_v6_conn_request,
993 .syn_recv_sock = dccp_v6_request_recv_sock,
994 .net_header_len = sizeof(struct ipv6hdr),
995 .setsockopt = ipv6_setsockopt,
996 .getsockopt = ipv6_getsockopt,
997 .addr2sockaddr = inet6_csk_addr2sockaddr,
998 .sockaddr_len = sizeof(struct sockaddr_in6),
999 .bind_conflict = inet6_csk_bind_conflict,
1000 #ifdef CONFIG_COMPAT
1001 .compat_setsockopt = compat_ipv6_setsockopt,
1002 .compat_getsockopt = compat_ipv6_getsockopt,
1003 #endif
1007 * DCCP over IPv4 via INET6 API
1009 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1010 .queue_xmit = ip_queue_xmit,
1011 .send_check = dccp_v4_send_check,
1012 .rebuild_header = inet_sk_rebuild_header,
1013 .conn_request = dccp_v6_conn_request,
1014 .syn_recv_sock = dccp_v6_request_recv_sock,
1015 .net_header_len = sizeof(struct iphdr),
1016 .setsockopt = ipv6_setsockopt,
1017 .getsockopt = ipv6_getsockopt,
1018 .addr2sockaddr = inet6_csk_addr2sockaddr,
1019 .sockaddr_len = sizeof(struct sockaddr_in6),
1020 #ifdef CONFIG_COMPAT
1021 .compat_setsockopt = compat_ipv6_setsockopt,
1022 .compat_getsockopt = compat_ipv6_getsockopt,
1023 #endif
1026 /* NOTE: A lot of things set to zero explicitly by call to
1027 * sk_alloc() so need not be done here.
1029 static int dccp_v6_init_sock(struct sock *sk)
1031 static __u8 dccp_v6_ctl_sock_initialized;
1032 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1034 if (err == 0) {
1035 if (unlikely(!dccp_v6_ctl_sock_initialized))
1036 dccp_v6_ctl_sock_initialized = 1;
1037 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1040 return err;
1043 static void dccp_v6_destroy_sock(struct sock *sk)
1045 dccp_destroy_sock(sk);
1046 inet6_destroy_sock(sk);
1049 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1050 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1053 static struct proto dccp_v6_prot = {
1054 .name = "DCCPv6",
1055 .owner = THIS_MODULE,
1056 .close = dccp_close,
1057 .connect = dccp_v6_connect,
1058 .disconnect = dccp_disconnect,
1059 .ioctl = dccp_ioctl,
1060 .init = dccp_v6_init_sock,
1061 .setsockopt = dccp_setsockopt,
1062 .getsockopt = dccp_getsockopt,
1063 .sendmsg = dccp_sendmsg,
1064 .recvmsg = dccp_recvmsg,
1065 .backlog_rcv = dccp_v6_do_rcv,
1066 .hash = dccp_v6_hash,
1067 .unhash = inet_unhash,
1068 .accept = inet_csk_accept,
1069 .get_port = inet_csk_get_port,
1070 .shutdown = dccp_shutdown,
1071 .destroy = dccp_v6_destroy_sock,
1072 .orphan_count = &dccp_orphan_count,
1073 .max_header = MAX_DCCP_HEADER,
1074 .obj_size = sizeof(struct dccp6_sock),
1075 .slab_flags = SLAB_DESTROY_BY_RCU,
1076 .rsk_prot = &dccp6_request_sock_ops,
1077 .twsk_prot = &dccp6_timewait_sock_ops,
1078 .h.hashinfo = &dccp_hashinfo,
1079 #ifdef CONFIG_COMPAT
1080 .compat_setsockopt = compat_dccp_setsockopt,
1081 .compat_getsockopt = compat_dccp_getsockopt,
1082 #endif
1085 static const struct inet6_protocol dccp_v6_protocol = {
1086 .handler = dccp_v6_rcv,
1087 .err_handler = dccp_v6_err,
1088 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1091 static const struct proto_ops inet6_dccp_ops = {
1092 .family = PF_INET6,
1093 .owner = THIS_MODULE,
1094 .release = inet6_release,
1095 .bind = inet6_bind,
1096 .connect = inet_stream_connect,
1097 .socketpair = sock_no_socketpair,
1098 .accept = inet_accept,
1099 .getname = inet6_getname,
1100 .poll = dccp_poll,
1101 .ioctl = inet6_ioctl,
1102 .listen = inet_dccp_listen,
1103 .shutdown = inet_shutdown,
1104 .setsockopt = sock_common_setsockopt,
1105 .getsockopt = sock_common_getsockopt,
1106 .sendmsg = inet_sendmsg,
1107 .recvmsg = sock_common_recvmsg,
1108 .mmap = sock_no_mmap,
1109 .sendpage = sock_no_sendpage,
1110 #ifdef CONFIG_COMPAT
1111 .compat_setsockopt = compat_sock_common_setsockopt,
1112 .compat_getsockopt = compat_sock_common_getsockopt,
1113 #endif
1116 static struct inet_protosw dccp_v6_protosw = {
1117 .type = SOCK_DCCP,
1118 .protocol = IPPROTO_DCCP,
1119 .prot = &dccp_v6_prot,
1120 .ops = &inet6_dccp_ops,
1121 .flags = INET_PROTOSW_ICSK,
1124 static int __net_init dccp_v6_init_net(struct net *net)
1126 if (dccp_hashinfo.bhash == NULL)
1127 return -ESOCKTNOSUPPORT;
1129 return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6,
1130 SOCK_DCCP, IPPROTO_DCCP, net);
1133 static void __net_exit dccp_v6_exit_net(struct net *net)
1135 inet_ctl_sock_destroy(net->dccp.v6_ctl_sk);
1138 static struct pernet_operations dccp_v6_ops = {
1139 .init = dccp_v6_init_net,
1140 .exit = dccp_v6_exit_net,
1143 static int __init dccp_v6_init(void)
1145 int err = proto_register(&dccp_v6_prot, 1);
1147 if (err != 0)
1148 goto out;
1150 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1151 if (err != 0)
1152 goto out_unregister_proto;
1154 inet6_register_protosw(&dccp_v6_protosw);
1156 err = register_pernet_subsys(&dccp_v6_ops);
1157 if (err != 0)
1158 goto out_destroy_ctl_sock;
1159 out:
1160 return err;
1162 out_destroy_ctl_sock:
1163 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1164 inet6_unregister_protosw(&dccp_v6_protosw);
1165 out_unregister_proto:
1166 proto_unregister(&dccp_v6_prot);
1167 goto out;
1170 static void __exit dccp_v6_exit(void)
1172 unregister_pernet_subsys(&dccp_v6_ops);
1173 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1174 inet6_unregister_protosw(&dccp_v6_protosw);
1175 proto_unregister(&dccp_v6_prot);
1178 module_init(dccp_v6_init);
1179 module_exit(dccp_v6_exit);
1182 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1183 * values directly, Also cover the case where the protocol is not specified,
1184 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1186 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1187 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1188 MODULE_LICENSE("GPL");
1189 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1190 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");