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/xfrm.h>
19 #include <net/addrconf.h>
20 #include <net/inet_common.h>
21 #include <net/inet_hashtables.h>
22 #include <net/inet_sock.h>
23 #include <net/inet6_connection_sock.h>
24 #include <net/inet6_hashtables.h>
25 #include <net/ip6_route.h>
27 #include <net/protocol.h>
28 #include <net/transp_v6.h>
29 #include <net/ip6_checksum.h>
36 /* Socket used for sending RSTs and ACKs */
37 static struct socket *dccp_v6_ctl_socket;
39 static struct inet_connection_sock_af_ops dccp_ipv6_mapped;
40 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
42 static int dccp_v6_get_port(struct sock *sk, unsigned short snum)
44 return inet_csk_get_port(&dccp_hashinfo, sk, snum,
45 inet6_csk_bind_conflict);
48 static void dccp_v6_hash(struct sock *sk)
50 if (sk->sk_state != DCCP_CLOSED) {
51 if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) {
56 __inet6_hash(&dccp_hashinfo, sk);
61 /* add pseudo-header to DCCP checksum stored in skb->csum */
62 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
63 struct in6_addr *saddr,
64 struct in6_addr *daddr)
66 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
69 static inline void dccp_v6_send_check(struct sock *sk, int unused_value,
72 struct ipv6_pinfo *np = inet6_sk(sk);
73 struct dccp_hdr *dh = dccp_hdr(skb);
75 dccp_csum_outgoing(skb);
76 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &np->daddr);
79 static inline __u32 secure_dccpv6_sequence_number(__be32 *saddr, __be32 *daddr,
80 __be16 sport, __be16 dport )
82 return secure_tcpv6_sequence_number(saddr, daddr, sport, dport);
85 static inline __u32 dccp_v6_init_sequence(struct sk_buff *skb)
87 return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
88 ipv6_hdr(skb)->saddr.s6_addr32,
89 dccp_hdr(skb)->dccph_dport,
90 dccp_hdr(skb)->dccph_sport );
94 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
95 int type, int code, int offset, __be32 info)
97 struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data;
98 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
99 struct ipv6_pinfo *np;
104 sk = inet6_lookup(&dccp_hashinfo, &hdr->daddr, dh->dccph_dport,
105 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
108 ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
112 if (sk->sk_state == DCCP_TIME_WAIT) {
113 inet_twsk_put(inet_twsk(sk));
118 if (sock_owned_by_user(sk))
119 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
121 if (sk->sk_state == DCCP_CLOSED)
126 if (type == ICMPV6_PKT_TOOBIG) {
127 struct dst_entry *dst = NULL;
129 if (sock_owned_by_user(sk))
131 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
134 /* icmp should have updated the destination cache entry */
135 dst = __sk_dst_check(sk, np->dst_cookie);
137 struct inet_sock *inet = inet_sk(sk);
140 /* BUGGG_FUTURE: Again, it is not clear how
141 to handle rthdr case. Ignore this complexity
144 memset(&fl, 0, sizeof(fl));
145 fl.proto = IPPROTO_DCCP;
146 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
147 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
148 fl.oif = sk->sk_bound_dev_if;
149 fl.fl_ip_dport = inet->dport;
150 fl.fl_ip_sport = inet->sport;
151 security_sk_classify_flow(sk, &fl);
153 err = ip6_dst_lookup(sk, &dst, &fl);
155 sk->sk_err_soft = -err;
159 err = xfrm_lookup(&dst, &fl, sk, 0);
161 sk->sk_err_soft = -err;
167 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
168 dccp_sync_mss(sk, dst_mtu(dst));
169 } /* else let the usual retransmit timer handle it */
174 icmpv6_err_convert(type, code, &err);
176 seq = DCCP_SKB_CB(skb)->dccpd_seq;
177 /* Might be for an request_sock */
178 switch (sk->sk_state) {
179 struct request_sock *req, **prev;
181 if (sock_owned_by_user(sk))
184 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
185 &hdr->daddr, &hdr->saddr,
191 * ICMPs are not backlogged, hence we cannot get an established
194 BUG_TRAP(req->sk == NULL);
196 if (seq != dccp_rsk(req)->dreq_iss) {
197 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
201 inet_csk_reqsk_queue_drop(sk, req, prev);
204 case DCCP_REQUESTING:
205 case DCCP_RESPOND: /* Cannot happen.
206 It can, it SYNs are crossed. --ANK */
207 if (!sock_owned_by_user(sk)) {
208 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
211 * Wake people up to see the error
212 * (see connect in sock.c)
214 sk->sk_error_report(sk);
217 sk->sk_err_soft = err;
221 if (!sock_owned_by_user(sk) && np->recverr) {
223 sk->sk_error_report(sk);
225 sk->sk_err_soft = err;
233 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
234 struct dst_entry *dst)
236 struct inet6_request_sock *ireq6 = inet6_rsk(req);
237 struct ipv6_pinfo *np = inet6_sk(sk);
239 struct ipv6_txoptions *opt = NULL;
240 struct in6_addr *final_p = NULL, final;
244 memset(&fl, 0, sizeof(fl));
245 fl.proto = IPPROTO_DCCP;
246 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
247 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
248 fl.fl6_flowlabel = 0;
250 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
251 fl.fl_ip_sport = inet_sk(sk)->sport;
252 security_req_classify_flow(req, &fl);
257 if (opt != NULL && opt->srcrt != NULL) {
258 const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
260 ipv6_addr_copy(&final, &fl.fl6_dst);
261 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
265 err = ip6_dst_lookup(sk, &dst, &fl);
270 ipv6_addr_copy(&fl.fl6_dst, final_p);
272 err = xfrm_lookup(&dst, &fl, sk, 0);
277 skb = dccp_make_response(sk, dst, req);
279 struct dccp_hdr *dh = dccp_hdr(skb);
281 dh->dccph_checksum = dccp_v6_csum_finish(skb,
284 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
285 err = ip6_xmit(sk, skb, &fl, opt, 0);
286 err = net_xmit_eval(err);
290 if (opt != NULL && opt != np->opt)
291 sock_kfree_s(sk, opt, opt->tot_len);
296 static void dccp_v6_reqsk_destructor(struct request_sock *req)
298 if (inet6_rsk(req)->pktopts != NULL)
299 kfree_skb(inet6_rsk(req)->pktopts);
302 static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
304 struct ipv6hdr *rxip6h;
308 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
311 if (!ipv6_unicast_destination(rxskb))
314 skb = dccp_ctl_make_reset(dccp_v6_ctl_socket, rxskb);
318 rxip6h = ipv6_hdr(rxskb);
319 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
322 memset(&fl, 0, sizeof(fl));
323 ipv6_addr_copy(&fl.fl6_dst, &rxip6h->saddr);
324 ipv6_addr_copy(&fl.fl6_src, &rxip6h->daddr);
326 fl.proto = IPPROTO_DCCP;
327 fl.oif = inet6_iif(rxskb);
328 fl.fl_ip_dport = dccp_hdr(skb)->dccph_dport;
329 fl.fl_ip_sport = dccp_hdr(skb)->dccph_sport;
330 security_skb_classify_flow(rxskb, &fl);
332 /* sk = NULL, but it is safe for now. RST socket required. */
333 if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) {
334 if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) {
335 ip6_xmit(dccp_v6_ctl_socket->sk, skb, &fl, NULL, 0);
336 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
337 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
345 static struct request_sock_ops dccp6_request_sock_ops = {
347 .obj_size = sizeof(struct dccp6_request_sock),
348 .rtx_syn_ack = dccp_v6_send_response,
349 .send_ack = dccp_reqsk_send_ack,
350 .destructor = dccp_v6_reqsk_destructor,
351 .send_reset = dccp_v6_ctl_send_reset,
354 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
356 const struct dccp_hdr *dh = dccp_hdr(skb);
357 const struct ipv6hdr *iph = ipv6_hdr(skb);
359 struct request_sock **prev;
360 /* Find possible connection requests. */
361 struct request_sock *req = inet6_csk_search_req(sk, &prev,
367 return dccp_check_req(sk, skb, req, prev);
369 nsk = __inet6_lookup_established(&dccp_hashinfo,
370 &iph->saddr, dh->dccph_sport,
371 &iph->daddr, ntohs(dh->dccph_dport),
374 if (nsk->sk_state != DCCP_TIME_WAIT) {
378 inet_twsk_put(inet_twsk(nsk));
385 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
387 struct request_sock *req;
388 struct dccp_request_sock *dreq;
389 struct inet6_request_sock *ireq6;
390 struct ipv6_pinfo *np = inet6_sk(sk);
391 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
392 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
394 if (skb->protocol == htons(ETH_P_IP))
395 return dccp_v4_conn_request(sk, skb);
397 if (!ipv6_unicast_destination(skb))
398 return 0; /* discard, don't send a reset here */
400 if (dccp_bad_service_code(sk, service)) {
401 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
405 * There are no SYN attacks on IPv6, yet...
407 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
408 if (inet_csk_reqsk_queue_is_full(sk))
411 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
414 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
418 if (dccp_parse_options(sk, skb))
421 dccp_reqsk_init(req, skb);
423 if (security_inet_conn_request(sk, skb, req))
426 ireq6 = inet6_rsk(req);
427 ipv6_addr_copy(&ireq6->rmt_addr, &ipv6_hdr(skb)->saddr);
428 ipv6_addr_copy(&ireq6->loc_addr, &ipv6_hdr(skb)->daddr);
429 ireq6->pktopts = NULL;
431 if (ipv6_opt_accepted(sk, skb) ||
432 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
433 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
434 atomic_inc(&skb->users);
435 ireq6->pktopts = skb;
437 ireq6->iif = sk->sk_bound_dev_if;
439 /* So that link locals have meaning */
440 if (!sk->sk_bound_dev_if &&
441 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
442 ireq6->iif = inet6_iif(skb);
445 * Step 3: Process LISTEN state
447 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
449 * In fact we defer setting S.GSR, S.SWL, S.SWH to
450 * dccp_create_openreq_child.
452 dreq = dccp_rsk(req);
453 dreq->dreq_isr = dcb->dccpd_seq;
454 dreq->dreq_iss = dccp_v6_init_sequence(skb);
455 dreq->dreq_service = service;
457 if (dccp_v6_send_response(sk, req, NULL))
460 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
466 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
470 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
472 struct request_sock *req,
473 struct dst_entry *dst)
475 struct inet6_request_sock *ireq6 = inet6_rsk(req);
476 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
477 struct inet_sock *newinet;
478 struct dccp_sock *newdp;
479 struct dccp6_sock *newdp6;
481 struct ipv6_txoptions *opt;
483 if (skb->protocol == htons(ETH_P_IP)) {
487 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
491 newdp6 = (struct dccp6_sock *)newsk;
492 newdp = dccp_sk(newsk);
493 newinet = inet_sk(newsk);
494 newinet->pinet6 = &newdp6->inet6;
495 newnp = inet6_sk(newsk);
497 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
499 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
502 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
505 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
507 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
508 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
509 newnp->pktoptions = NULL;
511 newnp->mcast_oif = inet6_iif(skb);
512 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
515 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
516 * here, dccp_create_openreq_child now does this for us, see the comment in
517 * that function for the gory details. -acme
520 /* It is tricky place. Until this moment IPv4 tcp
521 worked with IPv6 icsk.icsk_af_ops.
524 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
531 if (sk_acceptq_is_full(sk))
535 struct in6_addr *final_p = NULL, final;
538 memset(&fl, 0, sizeof(fl));
539 fl.proto = IPPROTO_DCCP;
540 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
541 if (opt != NULL && opt->srcrt != NULL) {
542 const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
544 ipv6_addr_copy(&final, &fl.fl6_dst);
545 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
548 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
549 fl.oif = sk->sk_bound_dev_if;
550 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
551 fl.fl_ip_sport = inet_sk(sk)->sport;
552 security_sk_classify_flow(sk, &fl);
554 if (ip6_dst_lookup(sk, &dst, &fl))
558 ipv6_addr_copy(&fl.fl6_dst, final_p);
560 if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
564 newsk = dccp_create_openreq_child(sk, req, skb);
569 * No need to charge this sock to the relevant IPv6 refcnt debug socks
570 * count here, dccp_create_openreq_child now does this for us, see the
571 * comment in that function for the gory details. -acme
574 __ip6_dst_store(newsk, dst, NULL, NULL);
575 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
577 newdp6 = (struct dccp6_sock *)newsk;
578 newinet = inet_sk(newsk);
579 newinet->pinet6 = &newdp6->inet6;
580 newdp = dccp_sk(newsk);
581 newnp = inet6_sk(newsk);
583 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
585 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
586 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
587 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
588 newsk->sk_bound_dev_if = ireq6->iif;
590 /* Now IPv6 options...
592 First: no IPv4 options.
597 newnp->rxopt.all = np->rxopt.all;
599 /* Clone pktoptions received with SYN */
600 newnp->pktoptions = NULL;
601 if (ireq6->pktopts != NULL) {
602 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
603 kfree_skb(ireq6->pktopts);
604 ireq6->pktopts = NULL;
605 if (newnp->pktoptions)
606 skb_set_owner_r(newnp->pktoptions, newsk);
609 newnp->mcast_oif = inet6_iif(skb);
610 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
613 * Clone native IPv6 options from listening socket (if any)
615 * Yes, keeping reference count would be much more clever, but we make
616 * one more one thing there: reattach optmem to newsk.
619 newnp->opt = ipv6_dup_options(newsk, opt);
621 sock_kfree_s(sk, opt, opt->tot_len);
624 inet_csk(newsk)->icsk_ext_hdr_len = 0;
625 if (newnp->opt != NULL)
626 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
627 newnp->opt->opt_flen);
629 dccp_sync_mss(newsk, dst_mtu(dst));
631 newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
633 __inet6_hash(&dccp_hashinfo, newsk);
634 inet_inherit_port(&dccp_hashinfo, sk, newsk);
639 NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
641 NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
642 if (opt != NULL && opt != np->opt)
643 sock_kfree_s(sk, opt, opt->tot_len);
648 /* The socket must have it's spinlock held when we get
651 * We have a potential double-lock case here, so even when
652 * doing backlog processing we use the BH locking scheme.
653 * This is because we cannot sleep with the original spinlock
656 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
658 struct ipv6_pinfo *np = inet6_sk(sk);
659 struct sk_buff *opt_skb = NULL;
661 /* Imagine: socket is IPv6. IPv4 packet arrives,
662 goes to IPv4 receive handler and backlogged.
663 From backlog it always goes here. Kerboom...
664 Fortunately, dccp_rcv_established and rcv_established
665 handle them correctly, but it is not case with
666 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
669 if (skb->protocol == htons(ETH_P_IP))
670 return dccp_v4_do_rcv(sk, skb);
672 if (sk_filter(sk, skb))
676 * socket locking is here for SMP purposes as backlog rcv is currently
677 * called with bh processing disabled.
680 /* Do Stevens' IPV6_PKTOPTIONS.
682 Yes, guys, it is the only place in our code, where we
683 may make it not affecting IPv4.
684 The rest of code is protocol independent,
685 and I do not like idea to uglify IPv4.
687 Actually, all the idea behind IPV6_PKTOPTIONS
688 looks not very well thought. For now we latch
689 options, received in the last packet, enqueued
690 by tcp. Feel free to propose better solution.
695 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
696 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
698 opt_skb = skb_clone(skb, GFP_ATOMIC);
700 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
701 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
704 /* XXX This is where we would goto ipv6_pktoptions. */
705 __kfree_skb(opt_skb);
711 * Step 3: Process LISTEN state
712 * If S.state == LISTEN,
713 * If P.type == Request or P contains a valid Init Cookie option,
714 * (* Must scan the packet's options to check for Init
715 * Cookies. Only Init Cookies are processed here,
716 * however; other options are processed in Step 8. This
717 * scan need only be performed if the endpoint uses Init
719 * (* Generate a new socket and switch to that socket *)
720 * Set S := new socket for this port pair
722 * Choose S.ISS (initial seqno) or set from Init Cookies
723 * Initialize S.GAR := S.ISS
724 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
725 * Continue with S.state == RESPOND
726 * (* A Response packet will be generated in Step 11 *)
728 * Generate Reset(No Connection) unless P.type == Reset
729 * Drop packet and return
731 * NOTE: the check for the packet types is done in
732 * dccp_rcv_state_process
734 if (sk->sk_state == DCCP_LISTEN) {
735 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
740 * Queue it on the new socket if the new socket is active,
741 * otherwise we just shortcircuit this and continue with
745 if (dccp_child_process(sk, nsk, skb))
748 __kfree_skb(opt_skb);
753 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
756 /* XXX This is where we would goto ipv6_pktoptions. */
757 __kfree_skb(opt_skb);
762 dccp_v6_ctl_send_reset(sk, skb);
765 __kfree_skb(opt_skb);
770 static int dccp_v6_rcv(struct sk_buff **pskb)
772 const struct dccp_hdr *dh;
773 struct sk_buff *skb = *pskb;
777 /* Step 1: Check header basics */
779 if (dccp_invalid_packet(skb))
782 /* Step 1: If header checksum is incorrect, drop packet and return. */
783 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
784 &ipv6_hdr(skb)->daddr)) {
785 DCCP_WARN("dropped packet with invalid checksum\n");
791 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
792 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
794 if (dccp_packet_without_ack(skb))
795 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
797 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
800 * Look up flow ID in table and get corresponding socket */
801 sk = __inet6_lookup(&dccp_hashinfo, &ipv6_hdr(skb)->saddr,
803 &ipv6_hdr(skb)->daddr, ntohs(dh->dccph_dport),
810 dccp_pr_debug("failed to look up flow ID in table and "
811 "get corresponding socket\n");
817 * ... or S.state == TIMEWAIT,
818 * Generate Reset(No Connection) unless P.type == Reset
819 * Drop packet and return
821 if (sk->sk_state == DCCP_TIME_WAIT) {
822 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
823 inet_twsk_put(inet_twsk(sk));
828 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
829 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
830 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
832 min_cov = dccp_sk(sk)->dccps_pcrlen;
833 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
834 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
835 dh->dccph_cscov, min_cov);
836 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
837 goto discard_and_relse;
840 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
841 goto discard_and_relse;
843 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
846 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
851 * Generate Reset(No Connection) unless P.type == Reset
852 * Drop packet and return
854 if (dh->dccph_type != DCCP_PKT_RESET) {
855 DCCP_SKB_CB(skb)->dccpd_reset_code =
856 DCCP_RESET_CODE_NO_CONNECTION;
857 dccp_v6_ctl_send_reset(sk, skb);
869 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
872 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
873 struct inet_connection_sock *icsk = inet_csk(sk);
874 struct inet_sock *inet = inet_sk(sk);
875 struct ipv6_pinfo *np = inet6_sk(sk);
876 struct dccp_sock *dp = dccp_sk(sk);
877 struct in6_addr *saddr = NULL, *final_p = NULL, final;
879 struct dst_entry *dst;
883 dp->dccps_role = DCCP_ROLE_CLIENT;
885 if (addr_len < SIN6_LEN_RFC2133)
888 if (usin->sin6_family != AF_INET6)
889 return -EAFNOSUPPORT;
891 memset(&fl, 0, sizeof(fl));
894 fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
895 IP6_ECN_flow_init(fl.fl6_flowlabel);
896 if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) {
897 struct ip6_flowlabel *flowlabel;
898 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
899 if (flowlabel == NULL)
901 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
902 fl6_sock_release(flowlabel);
906 * connect() to INADDR_ANY means loopback (BSD'ism).
908 if (ipv6_addr_any(&usin->sin6_addr))
909 usin->sin6_addr.s6_addr[15] = 1;
911 addr_type = ipv6_addr_type(&usin->sin6_addr);
913 if (addr_type & IPV6_ADDR_MULTICAST)
916 if (addr_type & IPV6_ADDR_LINKLOCAL) {
917 if (addr_len >= sizeof(struct sockaddr_in6) &&
918 usin->sin6_scope_id) {
919 /* If interface is set while binding, indices
922 if (sk->sk_bound_dev_if &&
923 sk->sk_bound_dev_if != usin->sin6_scope_id)
926 sk->sk_bound_dev_if = usin->sin6_scope_id;
929 /* Connect to link-local address requires an interface */
930 if (!sk->sk_bound_dev_if)
934 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
935 np->flow_label = fl.fl6_flowlabel;
940 if (addr_type == IPV6_ADDR_MAPPED) {
941 u32 exthdrlen = icsk->icsk_ext_hdr_len;
942 struct sockaddr_in sin;
944 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
946 if (__ipv6_only_sock(sk))
949 sin.sin_family = AF_INET;
950 sin.sin_port = usin->sin6_port;
951 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
953 icsk->icsk_af_ops = &dccp_ipv6_mapped;
954 sk->sk_backlog_rcv = dccp_v4_do_rcv;
956 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
958 icsk->icsk_ext_hdr_len = exthdrlen;
959 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
960 sk->sk_backlog_rcv = dccp_v6_do_rcv;
963 ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
965 ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
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->sport;
981 security_sk_classify_flow(sk, &fl);
983 if (np->opt != NULL && np->opt->srcrt != NULL) {
984 const struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
986 ipv6_addr_copy(&final, &fl.fl6_dst);
987 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
991 err = ip6_dst_lookup(sk, &dst, &fl);
996 ipv6_addr_copy(&fl.fl6_dst, final_p);
998 err = __xfrm_lookup(&dst, &fl, sk, 1);
1000 if (err == -EREMOTE)
1001 err = ip6_dst_blackhole(sk, &dst, &fl);
1006 if (saddr == NULL) {
1007 saddr = &fl.fl6_src;
1008 ipv6_addr_copy(&np->rcv_saddr, saddr);
1011 /* set the source address */
1012 ipv6_addr_copy(&np->saddr, saddr);
1013 inet->rcv_saddr = LOOPBACK4_IPV6;
1015 __ip6_dst_store(sk, dst, NULL, NULL);
1017 icsk->icsk_ext_hdr_len = 0;
1018 if (np->opt != NULL)
1019 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
1020 np->opt->opt_nflen);
1022 inet->dport = usin->sin6_port;
1024 dccp_set_state(sk, DCCP_REQUESTING);
1025 err = inet6_hash_connect(&dccp_death_row, sk);
1029 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
1030 np->daddr.s6_addr32,
1031 inet->sport, inet->dport);
1032 err = dccp_connect(sk);
1039 dccp_set_state(sk, DCCP_CLOSED);
1043 sk->sk_route_caps = 0;
1047 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1048 .queue_xmit = inet6_csk_xmit,
1049 .send_check = dccp_v6_send_check,
1050 .rebuild_header = inet6_sk_rebuild_header,
1051 .conn_request = dccp_v6_conn_request,
1052 .syn_recv_sock = dccp_v6_request_recv_sock,
1053 .net_header_len = sizeof(struct ipv6hdr),
1054 .setsockopt = ipv6_setsockopt,
1055 .getsockopt = ipv6_getsockopt,
1056 .addr2sockaddr = inet6_csk_addr2sockaddr,
1057 .sockaddr_len = sizeof(struct sockaddr_in6),
1058 #ifdef CONFIG_COMPAT
1059 .compat_setsockopt = compat_ipv6_setsockopt,
1060 .compat_getsockopt = compat_ipv6_getsockopt,
1065 * DCCP over IPv4 via INET6 API
1067 static struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1068 .queue_xmit = ip_queue_xmit,
1069 .send_check = dccp_v4_send_check,
1070 .rebuild_header = inet_sk_rebuild_header,
1071 .conn_request = dccp_v6_conn_request,
1072 .syn_recv_sock = dccp_v6_request_recv_sock,
1073 .net_header_len = sizeof(struct iphdr),
1074 .setsockopt = ipv6_setsockopt,
1075 .getsockopt = ipv6_getsockopt,
1076 .addr2sockaddr = inet6_csk_addr2sockaddr,
1077 .sockaddr_len = sizeof(struct sockaddr_in6),
1078 #ifdef CONFIG_COMPAT
1079 .compat_setsockopt = compat_ipv6_setsockopt,
1080 .compat_getsockopt = compat_ipv6_getsockopt,
1084 /* NOTE: A lot of things set to zero explicitly by call to
1085 * sk_alloc() so need not be done here.
1087 static int dccp_v6_init_sock(struct sock *sk)
1089 static __u8 dccp_v6_ctl_sock_initialized;
1090 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1093 if (unlikely(!dccp_v6_ctl_sock_initialized))
1094 dccp_v6_ctl_sock_initialized = 1;
1095 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1101 static int dccp_v6_destroy_sock(struct sock *sk)
1103 dccp_destroy_sock(sk);
1104 return inet6_destroy_sock(sk);
1107 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1108 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1111 static struct proto dccp_v6_prot = {
1113 .owner = THIS_MODULE,
1114 .close = dccp_close,
1115 .connect = dccp_v6_connect,
1116 .disconnect = dccp_disconnect,
1117 .ioctl = dccp_ioctl,
1118 .init = dccp_v6_init_sock,
1119 .setsockopt = dccp_setsockopt,
1120 .getsockopt = dccp_getsockopt,
1121 .sendmsg = dccp_sendmsg,
1122 .recvmsg = dccp_recvmsg,
1123 .backlog_rcv = dccp_v6_do_rcv,
1124 .hash = dccp_v6_hash,
1125 .unhash = dccp_unhash,
1126 .accept = inet_csk_accept,
1127 .get_port = dccp_v6_get_port,
1128 .shutdown = dccp_shutdown,
1129 .destroy = dccp_v6_destroy_sock,
1130 .orphan_count = &dccp_orphan_count,
1131 .max_header = MAX_DCCP_HEADER,
1132 .obj_size = sizeof(struct dccp6_sock),
1133 .rsk_prot = &dccp6_request_sock_ops,
1134 .twsk_prot = &dccp6_timewait_sock_ops,
1135 #ifdef CONFIG_COMPAT
1136 .compat_setsockopt = compat_dccp_setsockopt,
1137 .compat_getsockopt = compat_dccp_getsockopt,
1141 static struct inet6_protocol dccp_v6_protocol = {
1142 .handler = dccp_v6_rcv,
1143 .err_handler = dccp_v6_err,
1144 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1147 static struct proto_ops inet6_dccp_ops = {
1149 .owner = THIS_MODULE,
1150 .release = inet6_release,
1152 .connect = inet_stream_connect,
1153 .socketpair = sock_no_socketpair,
1154 .accept = inet_accept,
1155 .getname = inet6_getname,
1157 .ioctl = inet6_ioctl,
1158 .listen = inet_dccp_listen,
1159 .shutdown = inet_shutdown,
1160 .setsockopt = sock_common_setsockopt,
1161 .getsockopt = sock_common_getsockopt,
1162 .sendmsg = inet_sendmsg,
1163 .recvmsg = sock_common_recvmsg,
1164 .mmap = sock_no_mmap,
1165 .sendpage = sock_no_sendpage,
1166 #ifdef CONFIG_COMPAT
1167 .compat_setsockopt = compat_sock_common_setsockopt,
1168 .compat_getsockopt = compat_sock_common_getsockopt,
1172 static struct inet_protosw dccp_v6_protosw = {
1174 .protocol = IPPROTO_DCCP,
1175 .prot = &dccp_v6_prot,
1176 .ops = &inet6_dccp_ops,
1178 .flags = INET_PROTOSW_ICSK,
1181 static int __init dccp_v6_init(void)
1183 int err = proto_register(&dccp_v6_prot, 1);
1188 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1190 goto out_unregister_proto;
1192 inet6_register_protosw(&dccp_v6_protosw);
1194 err = inet_csk_ctl_sock_create(&dccp_v6_ctl_socket, PF_INET6,
1195 SOCK_DCCP, IPPROTO_DCCP);
1197 goto out_unregister_protosw;
1200 out_unregister_protosw:
1201 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1202 inet6_unregister_protosw(&dccp_v6_protosw);
1203 out_unregister_proto:
1204 proto_unregister(&dccp_v6_prot);
1208 static void __exit dccp_v6_exit(void)
1210 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1211 inet6_unregister_protosw(&dccp_v6_protosw);
1212 proto_unregister(&dccp_v6_prot);
1215 module_init(dccp_v6_init);
1216 module_exit(dccp_v6_exit);
1219 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1220 * values directly, Also cover the case where the protocol is not specified,
1221 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1223 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-33-type-6");
1224 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-0-type-6");
1225 MODULE_LICENSE("GPL");
1226 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1227 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");