PM: Clean up PM_TRACE dependencies and drop unnecessary Kconfig option
[linux/fpc-iii.git] / net / dccp / ipv6.c
blobdca711df9b60cea9e8ecf259cfdfc3909c60d3bb
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>
33 #include "dccp.h"
34 #include "ipv6.h"
35 #include "feat.h"
37 /* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */
39 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped;
40 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
42 static void dccp_v6_hash(struct sock *sk)
44 if (sk->sk_state != DCCP_CLOSED) {
45 if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) {
46 inet_hash(sk);
47 return;
49 local_bh_disable();
50 __inet6_hash(sk, NULL);
51 local_bh_enable();
55 /* add pseudo-header to DCCP checksum stored in skb->csum */
56 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
57 struct in6_addr *saddr,
58 struct in6_addr *daddr)
60 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
63 static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
65 struct ipv6_pinfo *np = inet6_sk(sk);
66 struct dccp_hdr *dh = dccp_hdr(skb);
68 dccp_csum_outgoing(skb);
69 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &np->daddr);
72 static inline __u32 secure_dccpv6_sequence_number(__be32 *saddr, __be32 *daddr,
73 __be16 sport, __be16 dport )
75 return secure_tcpv6_sequence_number(saddr, daddr, sport, dport);
78 static inline __u32 dccp_v6_init_sequence(struct sk_buff *skb)
80 return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
81 ipv6_hdr(skb)->saddr.s6_addr32,
82 dccp_hdr(skb)->dccph_dport,
83 dccp_hdr(skb)->dccph_sport );
87 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
88 u8 type, u8 code, int offset, __be32 info)
90 struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data;
91 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
92 struct dccp_sock *dp;
93 struct ipv6_pinfo *np;
94 struct sock *sk;
95 int err;
96 __u64 seq;
97 struct net *net = dev_net(skb->dev);
99 if (skb->len < offset + sizeof(*dh) ||
100 skb->len < offset + __dccp_basic_hdr_len(dh)) {
101 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
102 ICMP6_MIB_INERRORS);
103 return;
106 sk = inet6_lookup(net, &dccp_hashinfo,
107 &hdr->daddr, dh->dccph_dport,
108 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
110 if (sk == NULL) {
111 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
112 ICMP6_MIB_INERRORS);
113 return;
116 if (sk->sk_state == DCCP_TIME_WAIT) {
117 inet_twsk_put(inet_twsk(sk));
118 return;
121 bh_lock_sock(sk);
122 if (sock_owned_by_user(sk))
123 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
125 if (sk->sk_state == DCCP_CLOSED)
126 goto out;
128 dp = dccp_sk(sk);
129 seq = dccp_hdr_seq(dh);
130 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
131 !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
132 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
133 goto out;
136 np = inet6_sk(sk);
138 if (type == ICMPV6_PKT_TOOBIG) {
139 struct dst_entry *dst = NULL;
141 if (sock_owned_by_user(sk))
142 goto out;
143 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
144 goto out;
146 /* icmp should have updated the destination cache entry */
147 dst = __sk_dst_check(sk, np->dst_cookie);
148 if (dst == NULL) {
149 struct inet_sock *inet = inet_sk(sk);
150 struct flowi fl;
152 /* BUGGG_FUTURE: Again, it is not clear how
153 to handle rthdr case. Ignore this complexity
154 for now.
156 memset(&fl, 0, sizeof(fl));
157 fl.proto = IPPROTO_DCCP;
158 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
159 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
160 fl.oif = sk->sk_bound_dev_if;
161 fl.fl_ip_dport = inet->inet_dport;
162 fl.fl_ip_sport = inet->inet_sport;
163 security_sk_classify_flow(sk, &fl);
165 err = ip6_dst_lookup(sk, &dst, &fl);
166 if (err) {
167 sk->sk_err_soft = -err;
168 goto out;
171 err = xfrm_lookup(net, &dst, &fl, sk, 0);
172 if (err < 0) {
173 sk->sk_err_soft = -err;
174 goto out;
176 } else
177 dst_hold(dst);
179 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
180 dccp_sync_mss(sk, dst_mtu(dst));
181 } /* else let the usual retransmit timer handle it */
182 dst_release(dst);
183 goto out;
186 icmpv6_err_convert(type, code, &err);
188 /* Might be for an request_sock */
189 switch (sk->sk_state) {
190 struct request_sock *req, **prev;
191 case DCCP_LISTEN:
192 if (sock_owned_by_user(sk))
193 goto out;
195 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
196 &hdr->daddr, &hdr->saddr,
197 inet6_iif(skb));
198 if (req == NULL)
199 goto out;
202 * ICMPs are not backlogged, hence we cannot get an established
203 * socket here.
205 WARN_ON(req->sk != NULL);
207 if (seq != dccp_rsk(req)->dreq_iss) {
208 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
209 goto out;
212 inet_csk_reqsk_queue_drop(sk, req, prev);
213 goto out;
215 case DCCP_REQUESTING:
216 case DCCP_RESPOND: /* Cannot happen.
217 It can, it SYNs are crossed. --ANK */
218 if (!sock_owned_by_user(sk)) {
219 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
220 sk->sk_err = err;
222 * Wake people up to see the error
223 * (see connect in sock.c)
225 sk->sk_error_report(sk);
226 dccp_done(sk);
227 } else
228 sk->sk_err_soft = err;
229 goto out;
232 if (!sock_owned_by_user(sk) && np->recverr) {
233 sk->sk_err = err;
234 sk->sk_error_report(sk);
235 } else
236 sk->sk_err_soft = err;
238 out:
239 bh_unlock_sock(sk);
240 sock_put(sk);
244 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
245 struct request_values *rv_unused)
247 struct inet6_request_sock *ireq6 = inet6_rsk(req);
248 struct ipv6_pinfo *np = inet6_sk(sk);
249 struct sk_buff *skb;
250 struct ipv6_txoptions *opt = NULL;
251 struct in6_addr *final_p, final;
252 struct flowi fl;
253 int err = -1;
254 struct dst_entry *dst;
256 memset(&fl, 0, sizeof(fl));
257 fl.proto = IPPROTO_DCCP;
258 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
259 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
260 fl.fl6_flowlabel = 0;
261 fl.oif = ireq6->iif;
262 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
263 fl.fl_ip_sport = inet_rsk(req)->loc_port;
264 security_req_classify_flow(req, &fl);
266 opt = np->opt;
268 final_p = fl6_update_dst(&fl, opt, &final);
270 err = ip6_dst_lookup(sk, &dst, &fl);
271 if (err)
272 goto done;
274 if (final_p)
275 ipv6_addr_copy(&fl.fl6_dst, final_p);
277 err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0);
278 if (err < 0)
279 goto done;
281 skb = dccp_make_response(sk, dst, req);
282 if (skb != NULL) {
283 struct dccp_hdr *dh = dccp_hdr(skb);
285 dh->dccph_checksum = dccp_v6_csum_finish(skb,
286 &ireq6->loc_addr,
287 &ireq6->rmt_addr);
288 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
289 err = ip6_xmit(sk, skb, &fl, opt);
290 err = net_xmit_eval(err);
293 done:
294 if (opt != NULL && opt != np->opt)
295 sock_kfree_s(sk, opt, opt->tot_len);
296 dst_release(dst);
297 return err;
300 static void dccp_v6_reqsk_destructor(struct request_sock *req)
302 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
303 if (inet6_rsk(req)->pktopts != NULL)
304 kfree_skb(inet6_rsk(req)->pktopts);
307 static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
309 struct ipv6hdr *rxip6h;
310 struct sk_buff *skb;
311 struct flowi fl;
312 struct net *net = dev_net(skb_dst(rxskb)->dev);
313 struct sock *ctl_sk = net->dccp.v6_ctl_sk;
314 struct dst_entry *dst;
316 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
317 return;
319 if (!ipv6_unicast_destination(rxskb))
320 return;
322 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
323 if (skb == NULL)
324 return;
326 rxip6h = ipv6_hdr(rxskb);
327 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
328 &rxip6h->daddr);
330 memset(&fl, 0, sizeof(fl));
331 ipv6_addr_copy(&fl.fl6_dst, &rxip6h->saddr);
332 ipv6_addr_copy(&fl.fl6_src, &rxip6h->daddr);
334 fl.proto = IPPROTO_DCCP;
335 fl.oif = inet6_iif(rxskb);
336 fl.fl_ip_dport = dccp_hdr(skb)->dccph_dport;
337 fl.fl_ip_sport = dccp_hdr(skb)->dccph_sport;
338 security_skb_classify_flow(rxskb, &fl);
340 /* sk = NULL, but it is safe for now. RST socket required. */
341 if (!ip6_dst_lookup(ctl_sk, &dst, &fl)) {
342 if (xfrm_lookup(net, &dst, &fl, NULL, 0) >= 0) {
343 skb_dst_set(skb, dst);
344 ip6_xmit(ctl_sk, skb, &fl, NULL);
345 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
346 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
347 return;
351 kfree_skb(skb);
354 static struct request_sock_ops dccp6_request_sock_ops = {
355 .family = AF_INET6,
356 .obj_size = sizeof(struct dccp6_request_sock),
357 .rtx_syn_ack = dccp_v6_send_response,
358 .send_ack = dccp_reqsk_send_ack,
359 .destructor = dccp_v6_reqsk_destructor,
360 .send_reset = dccp_v6_ctl_send_reset,
363 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
365 const struct dccp_hdr *dh = dccp_hdr(skb);
366 const struct ipv6hdr *iph = ipv6_hdr(skb);
367 struct sock *nsk;
368 struct request_sock **prev;
369 /* Find possible connection requests. */
370 struct request_sock *req = inet6_csk_search_req(sk, &prev,
371 dh->dccph_sport,
372 &iph->saddr,
373 &iph->daddr,
374 inet6_iif(skb));
375 if (req != NULL)
376 return dccp_check_req(sk, skb, req, prev);
378 nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo,
379 &iph->saddr, dh->dccph_sport,
380 &iph->daddr, ntohs(dh->dccph_dport),
381 inet6_iif(skb));
382 if (nsk != NULL) {
383 if (nsk->sk_state != DCCP_TIME_WAIT) {
384 bh_lock_sock(nsk);
385 return nsk;
387 inet_twsk_put(inet_twsk(nsk));
388 return NULL;
391 return sk;
394 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
396 struct request_sock *req;
397 struct dccp_request_sock *dreq;
398 struct inet6_request_sock *ireq6;
399 struct ipv6_pinfo *np = inet6_sk(sk);
400 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
401 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
403 if (skb->protocol == htons(ETH_P_IP))
404 return dccp_v4_conn_request(sk, skb);
406 if (!ipv6_unicast_destination(skb))
407 return 0; /* discard, don't send a reset here */
409 if (dccp_bad_service_code(sk, service)) {
410 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
411 goto drop;
414 * There are no SYN attacks on IPv6, yet...
416 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
417 if (inet_csk_reqsk_queue_is_full(sk))
418 goto drop;
420 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
421 goto drop;
423 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
424 if (req == NULL)
425 goto drop;
427 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
428 goto drop_and_free;
430 dreq = dccp_rsk(req);
431 if (dccp_parse_options(sk, dreq, skb))
432 goto drop_and_free;
434 if (security_inet_conn_request(sk, skb, req))
435 goto drop_and_free;
437 ireq6 = inet6_rsk(req);
438 ipv6_addr_copy(&ireq6->rmt_addr, &ipv6_hdr(skb)->saddr);
439 ipv6_addr_copy(&ireq6->loc_addr, &ipv6_hdr(skb)->daddr);
441 if (ipv6_opt_accepted(sk, skb) ||
442 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
443 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
444 atomic_inc(&skb->users);
445 ireq6->pktopts = skb;
447 ireq6->iif = sk->sk_bound_dev_if;
449 /* So that link locals have meaning */
450 if (!sk->sk_bound_dev_if &&
451 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
452 ireq6->iif = inet6_iif(skb);
455 * Step 3: Process LISTEN state
457 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
459 * In fact we defer setting S.GSR, S.SWL, S.SWH to
460 * dccp_create_openreq_child.
462 dreq->dreq_isr = dcb->dccpd_seq;
463 dreq->dreq_iss = dccp_v6_init_sequence(skb);
464 dreq->dreq_service = service;
466 if (dccp_v6_send_response(sk, req, NULL))
467 goto drop_and_free;
469 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
470 return 0;
472 drop_and_free:
473 reqsk_free(req);
474 drop:
475 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
476 return -1;
479 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
480 struct sk_buff *skb,
481 struct request_sock *req,
482 struct dst_entry *dst)
484 struct inet6_request_sock *ireq6 = inet6_rsk(req);
485 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
486 struct inet_sock *newinet;
487 struct dccp_sock *newdp;
488 struct dccp6_sock *newdp6;
489 struct sock *newsk;
490 struct ipv6_txoptions *opt;
492 if (skb->protocol == htons(ETH_P_IP)) {
494 * v6 mapped
496 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
497 if (newsk == NULL)
498 return NULL;
500 newdp6 = (struct dccp6_sock *)newsk;
501 newdp = dccp_sk(newsk);
502 newinet = inet_sk(newsk);
503 newinet->pinet6 = &newdp6->inet6;
504 newnp = inet6_sk(newsk);
506 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
508 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr);
510 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
512 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
514 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
515 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
516 newnp->pktoptions = NULL;
517 newnp->opt = NULL;
518 newnp->mcast_oif = inet6_iif(skb);
519 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
522 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
523 * here, dccp_create_openreq_child now does this for us, see the comment in
524 * that function for the gory details. -acme
527 /* It is tricky place. Until this moment IPv4 tcp
528 worked with IPv6 icsk.icsk_af_ops.
529 Sync it now.
531 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
533 return newsk;
536 opt = np->opt;
538 if (sk_acceptq_is_full(sk))
539 goto out_overflow;
541 if (dst == NULL) {
542 struct in6_addr *final_p, final;
543 struct flowi fl;
545 memset(&fl, 0, sizeof(fl));
546 fl.proto = IPPROTO_DCCP;
547 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
548 final_p = fl6_update_dst(&fl, opt, &final);
549 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
550 fl.oif = sk->sk_bound_dev_if;
551 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
552 fl.fl_ip_sport = inet_rsk(req)->loc_port;
553 security_sk_classify_flow(sk, &fl);
555 if (ip6_dst_lookup(sk, &dst, &fl))
556 goto out;
558 if (final_p)
559 ipv6_addr_copy(&fl.fl6_dst, final_p);
561 if ((xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0)
562 goto out;
565 newsk = dccp_create_openreq_child(sk, req, skb);
566 if (newsk == NULL)
567 goto out_nonewsk;
570 * No need to charge this sock to the relevant IPv6 refcnt debug socks
571 * count here, dccp_create_openreq_child now does this for us, see the
572 * comment in that function for the gory details. -acme
575 __ip6_dst_store(newsk, dst, NULL, NULL);
576 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
577 NETIF_F_TSO);
578 newdp6 = (struct dccp6_sock *)newsk;
579 newinet = inet_sk(newsk);
580 newinet->pinet6 = &newdp6->inet6;
581 newdp = dccp_sk(newsk);
582 newnp = inet6_sk(newsk);
584 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
586 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
587 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
588 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
589 newsk->sk_bound_dev_if = ireq6->iif;
591 /* Now IPv6 options...
593 First: no IPv4 options.
595 newinet->opt = NULL;
597 /* Clone RX bits */
598 newnp->rxopt.all = np->rxopt.all;
600 /* Clone pktoptions received with SYN */
601 newnp->pktoptions = NULL;
602 if (ireq6->pktopts != NULL) {
603 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
604 kfree_skb(ireq6->pktopts);
605 ireq6->pktopts = NULL;
606 if (newnp->pktoptions)
607 skb_set_owner_r(newnp->pktoptions, newsk);
609 newnp->opt = NULL;
610 newnp->mcast_oif = inet6_iif(skb);
611 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
614 * Clone native IPv6 options from listening socket (if any)
616 * Yes, keeping reference count would be much more clever, but we make
617 * one more one thing there: reattach optmem to newsk.
619 if (opt != NULL) {
620 newnp->opt = ipv6_dup_options(newsk, opt);
621 if (opt != np->opt)
622 sock_kfree_s(sk, opt, opt->tot_len);
625 inet_csk(newsk)->icsk_ext_hdr_len = 0;
626 if (newnp->opt != NULL)
627 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
628 newnp->opt->opt_flen);
630 dccp_sync_mss(newsk, dst_mtu(dst));
632 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
633 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
635 if (__inet_inherit_port(sk, newsk) < 0) {
636 sock_put(newsk);
637 goto out;
639 __inet6_hash(newsk, NULL);
641 return newsk;
643 out_overflow:
644 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
645 out_nonewsk:
646 dst_release(dst);
647 out:
648 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
649 if (opt != NULL && opt != np->opt)
650 sock_kfree_s(sk, opt, opt->tot_len);
651 return NULL;
654 /* The socket must have it's spinlock held when we get
655 * here.
657 * We have a potential double-lock case here, so even when
658 * doing backlog processing we use the BH locking scheme.
659 * This is because we cannot sleep with the original spinlock
660 * held.
662 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
664 struct ipv6_pinfo *np = inet6_sk(sk);
665 struct sk_buff *opt_skb = NULL;
667 /* Imagine: socket is IPv6. IPv4 packet arrives,
668 goes to IPv4 receive handler and backlogged.
669 From backlog it always goes here. Kerboom...
670 Fortunately, dccp_rcv_established and rcv_established
671 handle them correctly, but it is not case with
672 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
675 if (skb->protocol == htons(ETH_P_IP))
676 return dccp_v4_do_rcv(sk, skb);
678 if (sk_filter(sk, skb))
679 goto discard;
682 * socket locking is here for SMP purposes as backlog rcv is currently
683 * called with bh processing disabled.
686 /* Do Stevens' IPV6_PKTOPTIONS.
688 Yes, guys, it is the only place in our code, where we
689 may make it not affecting IPv4.
690 The rest of code is protocol independent,
691 and I do not like idea to uglify IPv4.
693 Actually, all the idea behind IPV6_PKTOPTIONS
694 looks not very well thought. For now we latch
695 options, received in the last packet, enqueued
696 by tcp. Feel free to propose better solution.
697 --ANK (980728)
699 if (np->rxopt.all)
701 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
702 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
704 opt_skb = skb_clone(skb, GFP_ATOMIC);
706 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
707 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
708 goto reset;
709 if (opt_skb) {
710 /* XXX This is where we would goto ipv6_pktoptions. */
711 __kfree_skb(opt_skb);
713 return 0;
717 * Step 3: Process LISTEN state
718 * If S.state == LISTEN,
719 * If P.type == Request or P contains a valid Init Cookie option,
720 * (* Must scan the packet's options to check for Init
721 * Cookies. Only Init Cookies are processed here,
722 * however; other options are processed in Step 8. This
723 * scan need only be performed if the endpoint uses Init
724 * Cookies *)
725 * (* Generate a new socket and switch to that socket *)
726 * Set S := new socket for this port pair
727 * S.state = RESPOND
728 * Choose S.ISS (initial seqno) or set from Init Cookies
729 * Initialize S.GAR := S.ISS
730 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
731 * Continue with S.state == RESPOND
732 * (* A Response packet will be generated in Step 11 *)
733 * Otherwise,
734 * Generate Reset(No Connection) unless P.type == Reset
735 * Drop packet and return
737 * NOTE: the check for the packet types is done in
738 * dccp_rcv_state_process
740 if (sk->sk_state == DCCP_LISTEN) {
741 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
743 if (nsk == NULL)
744 goto discard;
746 * Queue it on the new socket if the new socket is active,
747 * otherwise we just shortcircuit this and continue with
748 * the new socket..
750 if (nsk != sk) {
751 if (dccp_child_process(sk, nsk, skb))
752 goto reset;
753 if (opt_skb != NULL)
754 __kfree_skb(opt_skb);
755 return 0;
759 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
760 goto reset;
761 if (opt_skb) {
762 /* XXX This is where we would goto ipv6_pktoptions. */
763 __kfree_skb(opt_skb);
765 return 0;
767 reset:
768 dccp_v6_ctl_send_reset(sk, skb);
769 discard:
770 if (opt_skb != NULL)
771 __kfree_skb(opt_skb);
772 kfree_skb(skb);
773 return 0;
776 static int dccp_v6_rcv(struct sk_buff *skb)
778 const struct dccp_hdr *dh;
779 struct sock *sk;
780 int min_cov;
782 /* Step 1: Check header basics */
784 if (dccp_invalid_packet(skb))
785 goto discard_it;
787 /* Step 1: If header checksum is incorrect, drop packet and return. */
788 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
789 &ipv6_hdr(skb)->daddr)) {
790 DCCP_WARN("dropped packet with invalid checksum\n");
791 goto discard_it;
794 dh = dccp_hdr(skb);
796 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
797 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
799 if (dccp_packet_without_ack(skb))
800 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
801 else
802 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
804 /* Step 2:
805 * Look up flow ID in table and get corresponding socket */
806 sk = __inet6_lookup_skb(&dccp_hashinfo, skb,
807 dh->dccph_sport, dh->dccph_dport);
809 * Step 2:
810 * If no socket ...
812 if (sk == NULL) {
813 dccp_pr_debug("failed to look up flow ID in table and "
814 "get corresponding socket\n");
815 goto no_dccp_socket;
819 * Step 2:
820 * ... or S.state == TIMEWAIT,
821 * Generate Reset(No Connection) unless P.type == Reset
822 * Drop packet and return
824 if (sk->sk_state == DCCP_TIME_WAIT) {
825 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
826 inet_twsk_put(inet_twsk(sk));
827 goto no_dccp_socket;
831 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
832 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
833 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
835 min_cov = dccp_sk(sk)->dccps_pcrlen;
836 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
837 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
838 dh->dccph_cscov, min_cov);
839 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
840 goto discard_and_relse;
843 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
844 goto discard_and_relse;
846 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
848 no_dccp_socket:
849 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
850 goto discard_it;
852 * Step 2:
853 * If no socket ...
854 * Generate Reset(No Connection) unless P.type == Reset
855 * Drop packet and return
857 if (dh->dccph_type != DCCP_PKT_RESET) {
858 DCCP_SKB_CB(skb)->dccpd_reset_code =
859 DCCP_RESET_CODE_NO_CONNECTION;
860 dccp_v6_ctl_send_reset(sk, skb);
863 discard_it:
864 kfree_skb(skb);
865 return 0;
867 discard_and_relse:
868 sock_put(sk);
869 goto discard_it;
872 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
873 int addr_len)
875 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
876 struct inet_connection_sock *icsk = inet_csk(sk);
877 struct inet_sock *inet = inet_sk(sk);
878 struct ipv6_pinfo *np = inet6_sk(sk);
879 struct dccp_sock *dp = dccp_sk(sk);
880 struct in6_addr *saddr = NULL, *final_p, final;
881 struct flowi fl;
882 struct dst_entry *dst;
883 int addr_type;
884 int err;
886 dp->dccps_role = DCCP_ROLE_CLIENT;
888 if (addr_len < SIN6_LEN_RFC2133)
889 return -EINVAL;
891 if (usin->sin6_family != AF_INET6)
892 return -EAFNOSUPPORT;
894 memset(&fl, 0, sizeof(fl));
896 if (np->sndflow) {
897 fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
898 IP6_ECN_flow_init(fl.fl6_flowlabel);
899 if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) {
900 struct ip6_flowlabel *flowlabel;
901 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
902 if (flowlabel == NULL)
903 return -EINVAL;
904 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
905 fl6_sock_release(flowlabel);
909 * connect() to INADDR_ANY means loopback (BSD'ism).
911 if (ipv6_addr_any(&usin->sin6_addr))
912 usin->sin6_addr.s6_addr[15] = 1;
914 addr_type = ipv6_addr_type(&usin->sin6_addr);
916 if (addr_type & IPV6_ADDR_MULTICAST)
917 return -ENETUNREACH;
919 if (addr_type & IPV6_ADDR_LINKLOCAL) {
920 if (addr_len >= sizeof(struct sockaddr_in6) &&
921 usin->sin6_scope_id) {
922 /* If interface is set while binding, indices
923 * must coincide.
925 if (sk->sk_bound_dev_if &&
926 sk->sk_bound_dev_if != usin->sin6_scope_id)
927 return -EINVAL;
929 sk->sk_bound_dev_if = usin->sin6_scope_id;
932 /* Connect to link-local address requires an interface */
933 if (!sk->sk_bound_dev_if)
934 return -EINVAL;
937 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
938 np->flow_label = fl.fl6_flowlabel;
941 * DCCP over IPv4
943 if (addr_type == IPV6_ADDR_MAPPED) {
944 u32 exthdrlen = icsk->icsk_ext_hdr_len;
945 struct sockaddr_in sin;
947 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
949 if (__ipv6_only_sock(sk))
950 return -ENETUNREACH;
952 sin.sin_family = AF_INET;
953 sin.sin_port = usin->sin6_port;
954 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
956 icsk->icsk_af_ops = &dccp_ipv6_mapped;
957 sk->sk_backlog_rcv = dccp_v4_do_rcv;
959 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
960 if (err) {
961 icsk->icsk_ext_hdr_len = exthdrlen;
962 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
963 sk->sk_backlog_rcv = dccp_v6_do_rcv;
964 goto failure;
966 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
967 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &np->rcv_saddr);
969 return err;
972 if (!ipv6_addr_any(&np->rcv_saddr))
973 saddr = &np->rcv_saddr;
975 fl.proto = IPPROTO_DCCP;
976 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
977 ipv6_addr_copy(&fl.fl6_src, saddr ? saddr : &np->saddr);
978 fl.oif = sk->sk_bound_dev_if;
979 fl.fl_ip_dport = usin->sin6_port;
980 fl.fl_ip_sport = inet->inet_sport;
981 security_sk_classify_flow(sk, &fl);
983 final_p = fl6_update_dst(&fl, np->opt, &final);
985 err = ip6_dst_lookup(sk, &dst, &fl);
986 if (err)
987 goto failure;
989 if (final_p)
990 ipv6_addr_copy(&fl.fl6_dst, final_p);
992 err = __xfrm_lookup(sock_net(sk), &dst, &fl, sk, XFRM_LOOKUP_WAIT);
993 if (err < 0) {
994 if (err == -EREMOTE)
995 err = ip6_dst_blackhole(sk, &dst, &fl);
996 if (err < 0)
997 goto failure;
1000 if (saddr == NULL) {
1001 saddr = &fl.fl6_src;
1002 ipv6_addr_copy(&np->rcv_saddr, saddr);
1005 /* set the source address */
1006 ipv6_addr_copy(&np->saddr, saddr);
1007 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
1009 __ip6_dst_store(sk, dst, NULL, NULL);
1011 icsk->icsk_ext_hdr_len = 0;
1012 if (np->opt != NULL)
1013 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
1014 np->opt->opt_nflen);
1016 inet->inet_dport = usin->sin6_port;
1018 dccp_set_state(sk, DCCP_REQUESTING);
1019 err = inet6_hash_connect(&dccp_death_row, sk);
1020 if (err)
1021 goto late_failure;
1023 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
1024 np->daddr.s6_addr32,
1025 inet->inet_sport,
1026 inet->inet_dport);
1027 err = dccp_connect(sk);
1028 if (err)
1029 goto late_failure;
1031 return 0;
1033 late_failure:
1034 dccp_set_state(sk, DCCP_CLOSED);
1035 __sk_dst_reset(sk);
1036 failure:
1037 inet->inet_dport = 0;
1038 sk->sk_route_caps = 0;
1039 return err;
1042 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1043 .queue_xmit = inet6_csk_xmit,
1044 .send_check = dccp_v6_send_check,
1045 .rebuild_header = inet6_sk_rebuild_header,
1046 .conn_request = dccp_v6_conn_request,
1047 .syn_recv_sock = dccp_v6_request_recv_sock,
1048 .net_header_len = sizeof(struct ipv6hdr),
1049 .setsockopt = ipv6_setsockopt,
1050 .getsockopt = ipv6_getsockopt,
1051 .addr2sockaddr = inet6_csk_addr2sockaddr,
1052 .sockaddr_len = sizeof(struct sockaddr_in6),
1053 .bind_conflict = inet6_csk_bind_conflict,
1054 #ifdef CONFIG_COMPAT
1055 .compat_setsockopt = compat_ipv6_setsockopt,
1056 .compat_getsockopt = compat_ipv6_getsockopt,
1057 #endif
1061 * DCCP over IPv4 via INET6 API
1063 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1064 .queue_xmit = ip_queue_xmit,
1065 .send_check = dccp_v4_send_check,
1066 .rebuild_header = inet_sk_rebuild_header,
1067 .conn_request = dccp_v6_conn_request,
1068 .syn_recv_sock = dccp_v6_request_recv_sock,
1069 .net_header_len = sizeof(struct iphdr),
1070 .setsockopt = ipv6_setsockopt,
1071 .getsockopt = ipv6_getsockopt,
1072 .addr2sockaddr = inet6_csk_addr2sockaddr,
1073 .sockaddr_len = sizeof(struct sockaddr_in6),
1074 #ifdef CONFIG_COMPAT
1075 .compat_setsockopt = compat_ipv6_setsockopt,
1076 .compat_getsockopt = compat_ipv6_getsockopt,
1077 #endif
1080 /* NOTE: A lot of things set to zero explicitly by call to
1081 * sk_alloc() so need not be done here.
1083 static int dccp_v6_init_sock(struct sock *sk)
1085 static __u8 dccp_v6_ctl_sock_initialized;
1086 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1088 if (err == 0) {
1089 if (unlikely(!dccp_v6_ctl_sock_initialized))
1090 dccp_v6_ctl_sock_initialized = 1;
1091 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1094 return err;
1097 static void dccp_v6_destroy_sock(struct sock *sk)
1099 dccp_destroy_sock(sk);
1100 inet6_destroy_sock(sk);
1103 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1104 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1107 static struct proto dccp_v6_prot = {
1108 .name = "DCCPv6",
1109 .owner = THIS_MODULE,
1110 .close = dccp_close,
1111 .connect = dccp_v6_connect,
1112 .disconnect = dccp_disconnect,
1113 .ioctl = dccp_ioctl,
1114 .init = dccp_v6_init_sock,
1115 .setsockopt = dccp_setsockopt,
1116 .getsockopt = dccp_getsockopt,
1117 .sendmsg = dccp_sendmsg,
1118 .recvmsg = dccp_recvmsg,
1119 .backlog_rcv = dccp_v6_do_rcv,
1120 .hash = dccp_v6_hash,
1121 .unhash = inet_unhash,
1122 .accept = inet_csk_accept,
1123 .get_port = inet_csk_get_port,
1124 .shutdown = dccp_shutdown,
1125 .destroy = dccp_v6_destroy_sock,
1126 .orphan_count = &dccp_orphan_count,
1127 .max_header = MAX_DCCP_HEADER,
1128 .obj_size = sizeof(struct dccp6_sock),
1129 .slab_flags = SLAB_DESTROY_BY_RCU,
1130 .rsk_prot = &dccp6_request_sock_ops,
1131 .twsk_prot = &dccp6_timewait_sock_ops,
1132 .h.hashinfo = &dccp_hashinfo,
1133 #ifdef CONFIG_COMPAT
1134 .compat_setsockopt = compat_dccp_setsockopt,
1135 .compat_getsockopt = compat_dccp_getsockopt,
1136 #endif
1139 static const struct inet6_protocol dccp_v6_protocol = {
1140 .handler = dccp_v6_rcv,
1141 .err_handler = dccp_v6_err,
1142 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1145 static const struct proto_ops inet6_dccp_ops = {
1146 .family = PF_INET6,
1147 .owner = THIS_MODULE,
1148 .release = inet6_release,
1149 .bind = inet6_bind,
1150 .connect = inet_stream_connect,
1151 .socketpair = sock_no_socketpair,
1152 .accept = inet_accept,
1153 .getname = inet6_getname,
1154 .poll = dccp_poll,
1155 .ioctl = inet6_ioctl,
1156 .listen = inet_dccp_listen,
1157 .shutdown = inet_shutdown,
1158 .setsockopt = sock_common_setsockopt,
1159 .getsockopt = sock_common_getsockopt,
1160 .sendmsg = inet_sendmsg,
1161 .recvmsg = sock_common_recvmsg,
1162 .mmap = sock_no_mmap,
1163 .sendpage = sock_no_sendpage,
1164 #ifdef CONFIG_COMPAT
1165 .compat_setsockopt = compat_sock_common_setsockopt,
1166 .compat_getsockopt = compat_sock_common_getsockopt,
1167 #endif
1170 static struct inet_protosw dccp_v6_protosw = {
1171 .type = SOCK_DCCP,
1172 .protocol = IPPROTO_DCCP,
1173 .prot = &dccp_v6_prot,
1174 .ops = &inet6_dccp_ops,
1175 .flags = INET_PROTOSW_ICSK,
1178 static int __net_init dccp_v6_init_net(struct net *net)
1180 if (dccp_hashinfo.bhash == NULL)
1181 return -ESOCKTNOSUPPORT;
1183 return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6,
1184 SOCK_DCCP, IPPROTO_DCCP, net);
1187 static void __net_exit dccp_v6_exit_net(struct net *net)
1189 inet_ctl_sock_destroy(net->dccp.v6_ctl_sk);
1192 static struct pernet_operations dccp_v6_ops = {
1193 .init = dccp_v6_init_net,
1194 .exit = dccp_v6_exit_net,
1197 static int __init dccp_v6_init(void)
1199 int err = proto_register(&dccp_v6_prot, 1);
1201 if (err != 0)
1202 goto out;
1204 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1205 if (err != 0)
1206 goto out_unregister_proto;
1208 inet6_register_protosw(&dccp_v6_protosw);
1210 err = register_pernet_subsys(&dccp_v6_ops);
1211 if (err != 0)
1212 goto out_destroy_ctl_sock;
1213 out:
1214 return err;
1216 out_destroy_ctl_sock:
1217 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1218 inet6_unregister_protosw(&dccp_v6_protosw);
1219 out_unregister_proto:
1220 proto_unregister(&dccp_v6_prot);
1221 goto out;
1224 static void __exit dccp_v6_exit(void)
1226 unregister_pernet_subsys(&dccp_v6_ops);
1227 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1228 inet6_unregister_protosw(&dccp_v6_protosw);
1229 proto_unregister(&dccp_v6_prot);
1232 module_init(dccp_v6_init);
1233 module_exit(dccp_v6_exit);
1236 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1237 * values directly, Also cover the case where the protocol is not specified,
1238 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1240 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1241 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1242 MODULE_LICENSE("GPL");
1243 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1244 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");