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>
28 #include <net/protocol.h>
29 #include <net/transp_v6.h>
30 #include <net/ip6_checksum.h>
32 #include <net/secure_seq.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) {
51 __inet6_hash(sk, NULL);
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, &np->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);
88 struct ipv6_pinfo *np;
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),
101 sk = inet6_lookup(net, &dccp_hashinfo,
102 &hdr->daddr, dh->dccph_dport,
103 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
106 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
111 if (sk->sk_state == DCCP_TIME_WAIT) {
112 inet_twsk_put(inet_twsk(sk));
117 if (sock_owned_by_user(sk))
118 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
120 if (sk->sk_state == DCCP_CLOSED)
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);
133 if (type == ICMPV6_PKT_TOOBIG) {
134 struct dst_entry *dst = NULL;
136 if (sock_owned_by_user(sk))
138 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
141 /* icmp should have updated the destination cache entry */
142 dst = __sk_dst_check(sk, np->dst_cookie);
144 struct inet_sock *inet = inet_sk(sk);
147 /* BUGGG_FUTURE: Again, it is not clear how
148 to handle rthdr case. Ignore this complexity
151 memset(&fl6, 0, sizeof(fl6));
152 fl6.flowi6_proto = IPPROTO_DCCP;
153 fl6.daddr = np->daddr;
154 fl6.saddr = np->saddr;
155 fl6.flowi6_oif = sk->sk_bound_dev_if;
156 fl6.fl6_dport = inet->inet_dport;
157 fl6.fl6_sport = inet->inet_sport;
158 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
160 dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
162 sk->sk_err_soft = -PTR_ERR(dst);
168 dst->ops->update_pmtu(dst, ntohl(info));
170 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
171 dccp_sync_mss(sk, dst_mtu(dst));
172 } /* else let the usual retransmit timer handle it */
177 icmpv6_err_convert(type, code, &err);
179 /* Might be for an request_sock */
180 switch (sk->sk_state) {
181 struct request_sock *req, **prev;
183 if (sock_owned_by_user(sk))
186 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
187 &hdr->daddr, &hdr->saddr,
193 * ICMPs are not backlogged, hence we cannot get an established
196 WARN_ON(req->sk != NULL);
198 if (!between48(seq, dccp_rsk(req)->dreq_iss,
199 dccp_rsk(req)->dreq_gss)) {
200 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
204 inet_csk_reqsk_queue_drop(sk, req, prev);
207 case DCCP_REQUESTING:
208 case DCCP_RESPOND: /* Cannot happen.
209 It can, it SYNs are crossed. --ANK */
210 if (!sock_owned_by_user(sk)) {
211 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
214 * Wake people up to see the error
215 * (see connect in sock.c)
217 sk->sk_error_report(sk);
220 sk->sk_err_soft = err;
224 if (!sock_owned_by_user(sk) && np->recverr) {
226 sk->sk_error_report(sk);
228 sk->sk_err_soft = err;
236 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
237 struct request_values *rv_unused)
239 struct inet6_request_sock *ireq6 = inet6_rsk(req);
240 struct ipv6_pinfo *np = inet6_sk(sk);
242 struct in6_addr *final_p, final;
245 struct dst_entry *dst;
247 memset(&fl6, 0, sizeof(fl6));
248 fl6.flowi6_proto = IPPROTO_DCCP;
249 fl6.daddr = ireq6->rmt_addr;
250 fl6.saddr = ireq6->loc_addr;
252 fl6.flowi6_oif = ireq6->iif;
253 fl6.fl6_dport = inet_rsk(req)->rmt_port;
254 fl6.fl6_sport = inet_rsk(req)->loc_port;
255 security_req_classify_flow(req, flowi6_to_flowi(&fl6));
258 final_p = fl6_update_dst(&fl6, np->opt, &final);
260 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
267 skb = dccp_make_response(sk, dst, req);
269 struct dccp_hdr *dh = dccp_hdr(skb);
271 dh->dccph_checksum = dccp_v6_csum_finish(skb,
274 fl6.daddr = ireq6->rmt_addr;
275 err = ip6_xmit(sk, skb, &fl6, np->opt, np->tclass);
276 err = net_xmit_eval(err);
284 static void dccp_v6_reqsk_destructor(struct request_sock *req)
286 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
287 if (inet6_rsk(req)->pktopts != NULL)
288 kfree_skb(inet6_rsk(req)->pktopts);
291 static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
293 const struct ipv6hdr *rxip6h;
296 struct net *net = dev_net(skb_dst(rxskb)->dev);
297 struct sock *ctl_sk = net->dccp.v6_ctl_sk;
298 struct dst_entry *dst;
300 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
303 if (!ipv6_unicast_destination(rxskb))
306 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
310 rxip6h = ipv6_hdr(rxskb);
311 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
314 memset(&fl6, 0, sizeof(fl6));
315 fl6.daddr = rxip6h->saddr;
316 fl6.saddr = rxip6h->daddr;
318 fl6.flowi6_proto = IPPROTO_DCCP;
319 fl6.flowi6_oif = inet6_iif(rxskb);
320 fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
321 fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
322 security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
324 /* sk = NULL, but it is safe for now. RST socket required. */
325 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false);
327 skb_dst_set(skb, dst);
328 ip6_xmit(ctl_sk, skb, &fl6, NULL, 0);
329 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
330 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
337 static struct request_sock_ops dccp6_request_sock_ops = {
339 .obj_size = sizeof(struct dccp6_request_sock),
340 .rtx_syn_ack = dccp_v6_send_response,
341 .send_ack = dccp_reqsk_send_ack,
342 .destructor = dccp_v6_reqsk_destructor,
343 .send_reset = dccp_v6_ctl_send_reset,
344 .syn_ack_timeout = dccp_syn_ack_timeout,
347 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
349 const struct dccp_hdr *dh = dccp_hdr(skb);
350 const struct ipv6hdr *iph = ipv6_hdr(skb);
352 struct request_sock **prev;
353 /* Find possible connection requests. */
354 struct request_sock *req = inet6_csk_search_req(sk, &prev,
360 return dccp_check_req(sk, skb, req, prev);
362 nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo,
363 &iph->saddr, dh->dccph_sport,
364 &iph->daddr, ntohs(dh->dccph_dport),
367 if (nsk->sk_state != DCCP_TIME_WAIT) {
371 inet_twsk_put(inet_twsk(nsk));
378 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
380 struct request_sock *req;
381 struct dccp_request_sock *dreq;
382 struct inet6_request_sock *ireq6;
383 struct ipv6_pinfo *np = inet6_sk(sk);
384 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
385 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
387 if (skb->protocol == htons(ETH_P_IP))
388 return dccp_v4_conn_request(sk, skb);
390 if (!ipv6_unicast_destination(skb))
391 return 0; /* discard, don't send a reset here */
393 if (dccp_bad_service_code(sk, service)) {
394 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
398 * There are no SYN attacks on IPv6, yet...
400 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
401 if (inet_csk_reqsk_queue_is_full(sk))
404 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
407 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
411 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
414 dreq = dccp_rsk(req);
415 if (dccp_parse_options(sk, dreq, skb))
418 if (security_inet_conn_request(sk, skb, req))
421 ireq6 = inet6_rsk(req);
422 ireq6->rmt_addr = ipv6_hdr(skb)->saddr;
423 ireq6->loc_addr = ipv6_hdr(skb)->daddr;
425 if (ipv6_opt_accepted(sk, skb) ||
426 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
427 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
428 atomic_inc(&skb->users);
429 ireq6->pktopts = skb;
431 ireq6->iif = sk->sk_bound_dev_if;
433 /* So that link locals have meaning */
434 if (!sk->sk_bound_dev_if &&
435 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
436 ireq6->iif = inet6_iif(skb);
439 * Step 3: Process LISTEN state
441 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
443 * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
445 dreq->dreq_isr = dcb->dccpd_seq;
446 dreq->dreq_gsr = dreq->dreq_isr;
447 dreq->dreq_iss = dccp_v6_init_sequence(skb);
448 dreq->dreq_gss = dreq->dreq_iss;
449 dreq->dreq_service = service;
451 if (dccp_v6_send_response(sk, req, NULL))
454 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
460 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
464 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
466 struct request_sock *req,
467 struct dst_entry *dst)
469 struct inet6_request_sock *ireq6 = inet6_rsk(req);
470 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
471 struct inet_sock *newinet;
472 struct dccp6_sock *newdp6;
475 if (skb->protocol == htons(ETH_P_IP)) {
479 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
483 newdp6 = (struct dccp6_sock *)newsk;
484 newinet = inet_sk(newsk);
485 newinet->pinet6 = &newdp6->inet6;
486 newnp = inet6_sk(newsk);
488 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
490 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr);
492 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
494 newnp->rcv_saddr = newnp->saddr;
496 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
497 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
498 newnp->pktoptions = NULL;
500 newnp->mcast_oif = inet6_iif(skb);
501 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
504 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
505 * here, dccp_create_openreq_child now does this for us, see the comment in
506 * that function for the gory details. -acme
509 /* It is tricky place. Until this moment IPv4 tcp
510 worked with IPv6 icsk.icsk_af_ops.
513 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
519 if (sk_acceptq_is_full(sk))
523 struct in6_addr *final_p, final;
526 memset(&fl6, 0, sizeof(fl6));
527 fl6.flowi6_proto = IPPROTO_DCCP;
528 fl6.daddr = ireq6->rmt_addr;
529 final_p = fl6_update_dst(&fl6, np->opt, &final);
530 fl6.saddr = ireq6->loc_addr;
531 fl6.flowi6_oif = sk->sk_bound_dev_if;
532 fl6.fl6_dport = inet_rsk(req)->rmt_port;
533 fl6.fl6_sport = inet_rsk(req)->loc_port;
534 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
536 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
541 newsk = dccp_create_openreq_child(sk, req, skb);
546 * No need to charge this sock to the relevant IPv6 refcnt debug socks
547 * count here, dccp_create_openreq_child now does this for us, see the
548 * comment in that function for the gory details. -acme
551 __ip6_dst_store(newsk, dst, NULL, NULL);
552 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
554 newdp6 = (struct dccp6_sock *)newsk;
555 newinet = inet_sk(newsk);
556 newinet->pinet6 = &newdp6->inet6;
557 newnp = inet6_sk(newsk);
559 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
561 newnp->daddr = ireq6->rmt_addr;
562 newnp->saddr = ireq6->loc_addr;
563 newnp->rcv_saddr = ireq6->loc_addr;
564 newsk->sk_bound_dev_if = ireq6->iif;
566 /* Now IPv6 options...
568 First: no IPv4 options.
570 newinet->inet_opt = NULL;
573 newnp->rxopt.all = np->rxopt.all;
575 /* Clone pktoptions received with SYN */
576 newnp->pktoptions = NULL;
577 if (ireq6->pktopts != NULL) {
578 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
579 consume_skb(ireq6->pktopts);
580 ireq6->pktopts = NULL;
581 if (newnp->pktoptions)
582 skb_set_owner_r(newnp->pktoptions, newsk);
585 newnp->mcast_oif = inet6_iif(skb);
586 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
589 * Clone native IPv6 options from listening socket (if any)
591 * Yes, keeping reference count would be much more clever, but we make
592 * one more one thing there: reattach optmem to newsk.
595 newnp->opt = ipv6_dup_options(newsk, np->opt);
597 inet_csk(newsk)->icsk_ext_hdr_len = 0;
598 if (newnp->opt != NULL)
599 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
600 newnp->opt->opt_flen);
602 dccp_sync_mss(newsk, dst_mtu(dst));
604 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
605 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
607 if (__inet_inherit_port(sk, newsk) < 0) {
611 __inet6_hash(newsk, NULL);
616 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
620 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
624 /* The socket must have it's spinlock held when we get
627 * We have a potential double-lock case here, so even when
628 * doing backlog processing we use the BH locking scheme.
629 * This is because we cannot sleep with the original spinlock
632 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
634 struct ipv6_pinfo *np = inet6_sk(sk);
635 struct sk_buff *opt_skb = NULL;
637 /* Imagine: socket is IPv6. IPv4 packet arrives,
638 goes to IPv4 receive handler and backlogged.
639 From backlog it always goes here. Kerboom...
640 Fortunately, dccp_rcv_established and rcv_established
641 handle them correctly, but it is not case with
642 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
645 if (skb->protocol == htons(ETH_P_IP))
646 return dccp_v4_do_rcv(sk, skb);
648 if (sk_filter(sk, skb))
652 * socket locking is here for SMP purposes as backlog rcv is currently
653 * called with bh processing disabled.
656 /* Do Stevens' IPV6_PKTOPTIONS.
658 Yes, guys, it is the only place in our code, where we
659 may make it not affecting IPv4.
660 The rest of code is protocol independent,
661 and I do not like idea to uglify IPv4.
663 Actually, all the idea behind IPV6_PKTOPTIONS
664 looks not very well thought. For now we latch
665 options, received in the last packet, enqueued
666 by tcp. Feel free to propose better solution.
671 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
672 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
674 opt_skb = skb_clone(skb, GFP_ATOMIC);
676 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
677 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
680 /* XXX This is where we would goto ipv6_pktoptions. */
681 __kfree_skb(opt_skb);
687 * Step 3: Process LISTEN state
688 * If S.state == LISTEN,
689 * If P.type == Request or P contains a valid Init Cookie option,
690 * (* Must scan the packet's options to check for Init
691 * Cookies. Only Init Cookies are processed here,
692 * however; other options are processed in Step 8. This
693 * scan need only be performed if the endpoint uses Init
695 * (* Generate a new socket and switch to that socket *)
696 * Set S := new socket for this port pair
698 * Choose S.ISS (initial seqno) or set from Init Cookies
699 * Initialize S.GAR := S.ISS
700 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
701 * Continue with S.state == RESPOND
702 * (* A Response packet will be generated in Step 11 *)
704 * Generate Reset(No Connection) unless P.type == Reset
705 * Drop packet and return
707 * NOTE: the check for the packet types is done in
708 * dccp_rcv_state_process
710 if (sk->sk_state == DCCP_LISTEN) {
711 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
716 * Queue it on the new socket if the new socket is active,
717 * otherwise we just shortcircuit this and continue with
721 if (dccp_child_process(sk, nsk, skb))
724 __kfree_skb(opt_skb);
729 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
732 /* XXX This is where we would goto ipv6_pktoptions. */
733 __kfree_skb(opt_skb);
738 dccp_v6_ctl_send_reset(sk, skb);
741 __kfree_skb(opt_skb);
746 static int dccp_v6_rcv(struct sk_buff *skb)
748 const struct dccp_hdr *dh;
752 /* Step 1: Check header basics */
754 if (dccp_invalid_packet(skb))
757 /* Step 1: If header checksum is incorrect, drop packet and return. */
758 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
759 &ipv6_hdr(skb)->daddr)) {
760 DCCP_WARN("dropped packet with invalid checksum\n");
766 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
767 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
769 if (dccp_packet_without_ack(skb))
770 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
772 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
775 * Look up flow ID in table and get corresponding socket */
776 sk = __inet6_lookup_skb(&dccp_hashinfo, skb,
777 dh->dccph_sport, dh->dccph_dport);
783 dccp_pr_debug("failed to look up flow ID in table and "
784 "get corresponding socket\n");
790 * ... or S.state == TIMEWAIT,
791 * Generate Reset(No Connection) unless P.type == Reset
792 * Drop packet and return
794 if (sk->sk_state == DCCP_TIME_WAIT) {
795 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
796 inet_twsk_put(inet_twsk(sk));
801 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
802 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
803 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
805 min_cov = dccp_sk(sk)->dccps_pcrlen;
806 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
807 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
808 dh->dccph_cscov, min_cov);
809 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
810 goto discard_and_relse;
813 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
814 goto discard_and_relse;
816 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
819 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
824 * Generate Reset(No Connection) unless P.type == Reset
825 * Drop packet and return
827 if (dh->dccph_type != DCCP_PKT_RESET) {
828 DCCP_SKB_CB(skb)->dccpd_reset_code =
829 DCCP_RESET_CODE_NO_CONNECTION;
830 dccp_v6_ctl_send_reset(sk, skb);
842 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
845 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
846 struct inet_connection_sock *icsk = inet_csk(sk);
847 struct inet_sock *inet = inet_sk(sk);
848 struct ipv6_pinfo *np = inet6_sk(sk);
849 struct dccp_sock *dp = dccp_sk(sk);
850 struct in6_addr *saddr = NULL, *final_p, final;
852 struct dst_entry *dst;
856 dp->dccps_role = DCCP_ROLE_CLIENT;
858 if (addr_len < SIN6_LEN_RFC2133)
861 if (usin->sin6_family != AF_INET6)
862 return -EAFNOSUPPORT;
864 memset(&fl6, 0, sizeof(fl6));
867 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
868 IP6_ECN_flow_init(fl6.flowlabel);
869 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
870 struct ip6_flowlabel *flowlabel;
871 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
872 if (flowlabel == NULL)
874 usin->sin6_addr = flowlabel->dst;
875 fl6_sock_release(flowlabel);
879 * connect() to INADDR_ANY means loopback (BSD'ism).
881 if (ipv6_addr_any(&usin->sin6_addr))
882 usin->sin6_addr.s6_addr[15] = 1;
884 addr_type = ipv6_addr_type(&usin->sin6_addr);
886 if (addr_type & IPV6_ADDR_MULTICAST)
889 if (addr_type & IPV6_ADDR_LINKLOCAL) {
890 if (addr_len >= sizeof(struct sockaddr_in6) &&
891 usin->sin6_scope_id) {
892 /* If interface is set while binding, indices
895 if (sk->sk_bound_dev_if &&
896 sk->sk_bound_dev_if != usin->sin6_scope_id)
899 sk->sk_bound_dev_if = usin->sin6_scope_id;
902 /* Connect to link-local address requires an interface */
903 if (!sk->sk_bound_dev_if)
907 np->daddr = usin->sin6_addr;
908 np->flow_label = fl6.flowlabel;
913 if (addr_type == IPV6_ADDR_MAPPED) {
914 u32 exthdrlen = icsk->icsk_ext_hdr_len;
915 struct sockaddr_in sin;
917 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
919 if (__ipv6_only_sock(sk))
922 sin.sin_family = AF_INET;
923 sin.sin_port = usin->sin6_port;
924 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
926 icsk->icsk_af_ops = &dccp_ipv6_mapped;
927 sk->sk_backlog_rcv = dccp_v4_do_rcv;
929 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
931 icsk->icsk_ext_hdr_len = exthdrlen;
932 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
933 sk->sk_backlog_rcv = dccp_v6_do_rcv;
936 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
937 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &np->rcv_saddr);
942 if (!ipv6_addr_any(&np->rcv_saddr))
943 saddr = &np->rcv_saddr;
945 fl6.flowi6_proto = IPPROTO_DCCP;
946 fl6.daddr = np->daddr;
947 fl6.saddr = saddr ? *saddr : np->saddr;
948 fl6.flowi6_oif = sk->sk_bound_dev_if;
949 fl6.fl6_dport = usin->sin6_port;
950 fl6.fl6_sport = inet->inet_sport;
951 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
953 final_p = fl6_update_dst(&fl6, np->opt, &final);
955 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
963 np->rcv_saddr = *saddr;
966 /* set the source address */
968 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
970 __ip6_dst_store(sk, dst, NULL, NULL);
972 icsk->icsk_ext_hdr_len = 0;
974 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
977 inet->inet_dport = usin->sin6_port;
979 dccp_set_state(sk, DCCP_REQUESTING);
980 err = inet6_hash_connect(&dccp_death_row, sk);
984 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
988 err = dccp_connect(sk);
995 dccp_set_state(sk, DCCP_CLOSED);
998 inet->inet_dport = 0;
999 sk->sk_route_caps = 0;
1003 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1004 .queue_xmit = inet6_csk_xmit,
1005 .send_check = dccp_v6_send_check,
1006 .rebuild_header = inet6_sk_rebuild_header,
1007 .conn_request = dccp_v6_conn_request,
1008 .syn_recv_sock = dccp_v6_request_recv_sock,
1009 .net_header_len = sizeof(struct ipv6hdr),
1010 .setsockopt = ipv6_setsockopt,
1011 .getsockopt = ipv6_getsockopt,
1012 .addr2sockaddr = inet6_csk_addr2sockaddr,
1013 .sockaddr_len = sizeof(struct sockaddr_in6),
1014 .bind_conflict = inet6_csk_bind_conflict,
1015 #ifdef CONFIG_COMPAT
1016 .compat_setsockopt = compat_ipv6_setsockopt,
1017 .compat_getsockopt = compat_ipv6_getsockopt,
1022 * DCCP over IPv4 via INET6 API
1024 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1025 .queue_xmit = ip_queue_xmit,
1026 .send_check = dccp_v4_send_check,
1027 .rebuild_header = inet_sk_rebuild_header,
1028 .conn_request = dccp_v6_conn_request,
1029 .syn_recv_sock = dccp_v6_request_recv_sock,
1030 .net_header_len = sizeof(struct iphdr),
1031 .setsockopt = ipv6_setsockopt,
1032 .getsockopt = ipv6_getsockopt,
1033 .addr2sockaddr = inet6_csk_addr2sockaddr,
1034 .sockaddr_len = sizeof(struct sockaddr_in6),
1035 #ifdef CONFIG_COMPAT
1036 .compat_setsockopt = compat_ipv6_setsockopt,
1037 .compat_getsockopt = compat_ipv6_getsockopt,
1041 /* NOTE: A lot of things set to zero explicitly by call to
1042 * sk_alloc() so need not be done here.
1044 static int dccp_v6_init_sock(struct sock *sk)
1046 static __u8 dccp_v6_ctl_sock_initialized;
1047 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1050 if (unlikely(!dccp_v6_ctl_sock_initialized))
1051 dccp_v6_ctl_sock_initialized = 1;
1052 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1058 static void dccp_v6_destroy_sock(struct sock *sk)
1060 dccp_destroy_sock(sk);
1061 inet6_destroy_sock(sk);
1064 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1065 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1068 static struct proto dccp_v6_prot = {
1070 .owner = THIS_MODULE,
1071 .close = dccp_close,
1072 .connect = dccp_v6_connect,
1073 .disconnect = dccp_disconnect,
1074 .ioctl = dccp_ioctl,
1075 .init = dccp_v6_init_sock,
1076 .setsockopt = dccp_setsockopt,
1077 .getsockopt = dccp_getsockopt,
1078 .sendmsg = dccp_sendmsg,
1079 .recvmsg = dccp_recvmsg,
1080 .backlog_rcv = dccp_v6_do_rcv,
1081 .hash = dccp_v6_hash,
1082 .unhash = inet_unhash,
1083 .accept = inet_csk_accept,
1084 .get_port = inet_csk_get_port,
1085 .shutdown = dccp_shutdown,
1086 .destroy = dccp_v6_destroy_sock,
1087 .orphan_count = &dccp_orphan_count,
1088 .max_header = MAX_DCCP_HEADER,
1089 .obj_size = sizeof(struct dccp6_sock),
1090 .slab_flags = SLAB_DESTROY_BY_RCU,
1091 .rsk_prot = &dccp6_request_sock_ops,
1092 .twsk_prot = &dccp6_timewait_sock_ops,
1093 .h.hashinfo = &dccp_hashinfo,
1094 #ifdef CONFIG_COMPAT
1095 .compat_setsockopt = compat_dccp_setsockopt,
1096 .compat_getsockopt = compat_dccp_getsockopt,
1100 static const struct inet6_protocol dccp_v6_protocol = {
1101 .handler = dccp_v6_rcv,
1102 .err_handler = dccp_v6_err,
1103 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1106 static const struct proto_ops inet6_dccp_ops = {
1108 .owner = THIS_MODULE,
1109 .release = inet6_release,
1111 .connect = inet_stream_connect,
1112 .socketpair = sock_no_socketpair,
1113 .accept = inet_accept,
1114 .getname = inet6_getname,
1116 .ioctl = inet6_ioctl,
1117 .listen = inet_dccp_listen,
1118 .shutdown = inet_shutdown,
1119 .setsockopt = sock_common_setsockopt,
1120 .getsockopt = sock_common_getsockopt,
1121 .sendmsg = inet_sendmsg,
1122 .recvmsg = sock_common_recvmsg,
1123 .mmap = sock_no_mmap,
1124 .sendpage = sock_no_sendpage,
1125 #ifdef CONFIG_COMPAT
1126 .compat_setsockopt = compat_sock_common_setsockopt,
1127 .compat_getsockopt = compat_sock_common_getsockopt,
1131 static struct inet_protosw dccp_v6_protosw = {
1133 .protocol = IPPROTO_DCCP,
1134 .prot = &dccp_v6_prot,
1135 .ops = &inet6_dccp_ops,
1136 .flags = INET_PROTOSW_ICSK,
1139 static int __net_init dccp_v6_init_net(struct net *net)
1141 if (dccp_hashinfo.bhash == NULL)
1142 return -ESOCKTNOSUPPORT;
1144 return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6,
1145 SOCK_DCCP, IPPROTO_DCCP, net);
1148 static void __net_exit dccp_v6_exit_net(struct net *net)
1150 inet_ctl_sock_destroy(net->dccp.v6_ctl_sk);
1153 static struct pernet_operations dccp_v6_ops = {
1154 .init = dccp_v6_init_net,
1155 .exit = dccp_v6_exit_net,
1158 static int __init dccp_v6_init(void)
1160 int err = proto_register(&dccp_v6_prot, 1);
1165 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1167 goto out_unregister_proto;
1169 inet6_register_protosw(&dccp_v6_protosw);
1171 err = register_pernet_subsys(&dccp_v6_ops);
1173 goto out_destroy_ctl_sock;
1177 out_destroy_ctl_sock:
1178 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1179 inet6_unregister_protosw(&dccp_v6_protosw);
1180 out_unregister_proto:
1181 proto_unregister(&dccp_v6_prot);
1185 static void __exit dccp_v6_exit(void)
1187 unregister_pernet_subsys(&dccp_v6_ops);
1188 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1189 inet6_unregister_protosw(&dccp_v6_protosw);
1190 proto_unregister(&dccp_v6_prot);
1193 module_init(dccp_v6_init);
1194 module_exit(dccp_v6_exit);
1197 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1198 * values directly, Also cover the case where the protocol is not specified,
1199 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1201 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1202 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1203 MODULE_LICENSE("GPL");
1204 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1205 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");