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>
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) {
50 __inet6_hash(sk, NULL);
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);
93 struct ipv6_pinfo *np;
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),
106 sk = inet6_lookup(net, &dccp_hashinfo,
107 &hdr->daddr, dh->dccph_dport,
108 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
111 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
116 if (sk->sk_state == DCCP_TIME_WAIT) {
117 inet_twsk_put(inet_twsk(sk));
122 if (sock_owned_by_user(sk))
123 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
125 if (sk->sk_state == DCCP_CLOSED)
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);
138 if (type == ICMPV6_PKT_TOOBIG) {
139 struct dst_entry *dst = NULL;
141 if (sock_owned_by_user(sk))
143 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
146 /* icmp should have updated the destination cache entry */
147 dst = __sk_dst_check(sk, np->dst_cookie);
149 struct inet_sock *inet = inet_sk(sk);
152 /* BUGGG_FUTURE: Again, it is not clear how
153 to handle rthdr case. Ignore this complexity
156 memset(&fl6, 0, sizeof(fl6));
157 fl6.flowi6_proto = IPPROTO_DCCP;
158 ipv6_addr_copy(&fl6.daddr, &np->daddr);
159 ipv6_addr_copy(&fl6.saddr, &np->saddr);
160 fl6.flowi6_oif = sk->sk_bound_dev_if;
161 fl6.fl6_dport = inet->inet_dport;
162 fl6.fl6_sport = inet->inet_sport;
163 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
165 dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
167 sk->sk_err_soft = -PTR_ERR(dst);
173 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
174 dccp_sync_mss(sk, dst_mtu(dst));
175 } /* else let the usual retransmit timer handle it */
180 icmpv6_err_convert(type, code, &err);
182 /* Might be for an request_sock */
183 switch (sk->sk_state) {
184 struct request_sock *req, **prev;
186 if (sock_owned_by_user(sk))
189 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
190 &hdr->daddr, &hdr->saddr,
196 * ICMPs are not backlogged, hence we cannot get an established
199 WARN_ON(req->sk != NULL);
201 if (seq != dccp_rsk(req)->dreq_iss) {
202 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
206 inet_csk_reqsk_queue_drop(sk, req, prev);
209 case DCCP_REQUESTING:
210 case DCCP_RESPOND: /* Cannot happen.
211 It can, it SYNs are crossed. --ANK */
212 if (!sock_owned_by_user(sk)) {
213 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
216 * Wake people up to see the error
217 * (see connect in sock.c)
219 sk->sk_error_report(sk);
222 sk->sk_err_soft = err;
226 if (!sock_owned_by_user(sk) && np->recverr) {
228 sk->sk_error_report(sk);
230 sk->sk_err_soft = err;
238 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
239 struct request_values *rv_unused)
241 struct inet6_request_sock *ireq6 = inet6_rsk(req);
242 struct ipv6_pinfo *np = inet6_sk(sk);
244 struct ipv6_txoptions *opt = NULL;
245 struct in6_addr *final_p, final;
248 struct dst_entry *dst;
250 memset(&fl6, 0, sizeof(fl6));
251 fl6.flowi6_proto = IPPROTO_DCCP;
252 ipv6_addr_copy(&fl6.daddr, &ireq6->rmt_addr);
253 ipv6_addr_copy(&fl6.saddr, &ireq6->loc_addr);
255 fl6.flowi6_oif = ireq6->iif;
256 fl6.fl6_dport = inet_rsk(req)->rmt_port;
257 fl6.fl6_sport = inet_rsk(req)->loc_port;
258 security_req_classify_flow(req, flowi6_to_flowi(&fl6));
262 final_p = fl6_update_dst(&fl6, opt, &final);
264 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
271 skb = dccp_make_response(sk, dst, req);
273 struct dccp_hdr *dh = dccp_hdr(skb);
275 dh->dccph_checksum = dccp_v6_csum_finish(skb,
278 ipv6_addr_copy(&fl6.daddr, &ireq6->rmt_addr);
279 err = ip6_xmit(sk, skb, &fl6, opt);
280 err = net_xmit_eval(err);
284 if (opt != NULL && opt != np->opt)
285 sock_kfree_s(sk, opt, opt->tot_len);
290 static void dccp_v6_reqsk_destructor(struct request_sock *req)
292 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
293 if (inet6_rsk(req)->pktopts != NULL)
294 kfree_skb(inet6_rsk(req)->pktopts);
297 static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
299 struct ipv6hdr *rxip6h;
302 struct net *net = dev_net(skb_dst(rxskb)->dev);
303 struct sock *ctl_sk = net->dccp.v6_ctl_sk;
304 struct dst_entry *dst;
306 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
309 if (!ipv6_unicast_destination(rxskb))
312 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
316 rxip6h = ipv6_hdr(rxskb);
317 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
320 memset(&fl6, 0, sizeof(fl6));
321 ipv6_addr_copy(&fl6.daddr, &rxip6h->saddr);
322 ipv6_addr_copy(&fl6.saddr, &rxip6h->daddr);
324 fl6.flowi6_proto = IPPROTO_DCCP;
325 fl6.flowi6_oif = inet6_iif(rxskb);
326 fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
327 fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
328 security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
330 /* sk = NULL, but it is safe for now. RST socket required. */
331 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false);
333 skb_dst_set(skb, dst);
334 ip6_xmit(ctl_sk, skb, &fl6, NULL);
335 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
336 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
343 static struct request_sock_ops dccp6_request_sock_ops = {
345 .obj_size = sizeof(struct dccp6_request_sock),
346 .rtx_syn_ack = dccp_v6_send_response,
347 .send_ack = dccp_reqsk_send_ack,
348 .destructor = dccp_v6_reqsk_destructor,
349 .send_reset = dccp_v6_ctl_send_reset,
352 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
354 const struct dccp_hdr *dh = dccp_hdr(skb);
355 const struct ipv6hdr *iph = ipv6_hdr(skb);
357 struct request_sock **prev;
358 /* Find possible connection requests. */
359 struct request_sock *req = inet6_csk_search_req(sk, &prev,
365 return dccp_check_req(sk, skb, req, prev);
367 nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo,
368 &iph->saddr, dh->dccph_sport,
369 &iph->daddr, ntohs(dh->dccph_dport),
372 if (nsk->sk_state != DCCP_TIME_WAIT) {
376 inet_twsk_put(inet_twsk(nsk));
383 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
385 struct request_sock *req;
386 struct dccp_request_sock *dreq;
387 struct inet6_request_sock *ireq6;
388 struct ipv6_pinfo *np = inet6_sk(sk);
389 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
390 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
392 if (skb->protocol == htons(ETH_P_IP))
393 return dccp_v4_conn_request(sk, skb);
395 if (!ipv6_unicast_destination(skb))
396 return 0; /* discard, don't send a reset here */
398 if (dccp_bad_service_code(sk, service)) {
399 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
403 * There are no SYN attacks on IPv6, yet...
405 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
406 if (inet_csk_reqsk_queue_is_full(sk))
409 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
412 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
416 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
419 dreq = dccp_rsk(req);
420 if (dccp_parse_options(sk, dreq, 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);
430 if (ipv6_opt_accepted(sk, skb) ||
431 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
432 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
433 atomic_inc(&skb->users);
434 ireq6->pktopts = skb;
436 ireq6->iif = sk->sk_bound_dev_if;
438 /* So that link locals have meaning */
439 if (!sk->sk_bound_dev_if &&
440 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
441 ireq6->iif = inet6_iif(skb);
444 * Step 3: Process LISTEN state
446 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
448 * In fact we defer setting S.GSR, S.SWL, S.SWH to
449 * dccp_create_openreq_child.
451 dreq->dreq_isr = dcb->dccpd_seq;
452 dreq->dreq_iss = dccp_v6_init_sequence(skb);
453 dreq->dreq_service = service;
455 if (dccp_v6_send_response(sk, req, NULL))
458 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
464 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
468 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
470 struct request_sock *req,
471 struct dst_entry *dst)
473 struct inet6_request_sock *ireq6 = inet6_rsk(req);
474 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
475 struct inet_sock *newinet;
476 struct dccp6_sock *newdp6;
478 struct ipv6_txoptions *opt;
480 if (skb->protocol == htons(ETH_P_IP)) {
484 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
488 newdp6 = (struct dccp6_sock *)newsk;
489 newinet = inet_sk(newsk);
490 newinet->pinet6 = &newdp6->inet6;
491 newnp = inet6_sk(newsk);
493 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
495 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr);
497 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
499 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
501 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
502 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
503 newnp->pktoptions = NULL;
505 newnp->mcast_oif = inet6_iif(skb);
506 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
509 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
510 * here, dccp_create_openreq_child now does this for us, see the comment in
511 * that function for the gory details. -acme
514 /* It is tricky place. Until this moment IPv4 tcp
515 worked with IPv6 icsk.icsk_af_ops.
518 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
525 if (sk_acceptq_is_full(sk))
529 struct in6_addr *final_p, final;
532 memset(&fl6, 0, sizeof(fl6));
533 fl6.flowi6_proto = IPPROTO_DCCP;
534 ipv6_addr_copy(&fl6.daddr, &ireq6->rmt_addr);
535 final_p = fl6_update_dst(&fl6, opt, &final);
536 ipv6_addr_copy(&fl6.saddr, &ireq6->loc_addr);
537 fl6.flowi6_oif = sk->sk_bound_dev_if;
538 fl6.fl6_dport = inet_rsk(req)->rmt_port;
539 fl6.fl6_sport = inet_rsk(req)->loc_port;
540 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
542 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
547 newsk = dccp_create_openreq_child(sk, req, skb);
552 * No need to charge this sock to the relevant IPv6 refcnt debug socks
553 * count here, dccp_create_openreq_child now does this for us, see the
554 * comment in that function for the gory details. -acme
557 __ip6_dst_store(newsk, dst, NULL, NULL);
558 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
560 newdp6 = (struct dccp6_sock *)newsk;
561 newinet = inet_sk(newsk);
562 newinet->pinet6 = &newdp6->inet6;
563 newnp = inet6_sk(newsk);
565 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
567 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
568 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
569 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
570 newsk->sk_bound_dev_if = ireq6->iif;
572 /* Now IPv6 options...
574 First: no IPv4 options.
579 newnp->rxopt.all = np->rxopt.all;
581 /* Clone pktoptions received with SYN */
582 newnp->pktoptions = NULL;
583 if (ireq6->pktopts != NULL) {
584 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
585 kfree_skb(ireq6->pktopts);
586 ireq6->pktopts = NULL;
587 if (newnp->pktoptions)
588 skb_set_owner_r(newnp->pktoptions, newsk);
591 newnp->mcast_oif = inet6_iif(skb);
592 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
595 * Clone native IPv6 options from listening socket (if any)
597 * Yes, keeping reference count would be much more clever, but we make
598 * one more one thing there: reattach optmem to newsk.
601 newnp->opt = ipv6_dup_options(newsk, opt);
603 sock_kfree_s(sk, opt, opt->tot_len);
606 inet_csk(newsk)->icsk_ext_hdr_len = 0;
607 if (newnp->opt != NULL)
608 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
609 newnp->opt->opt_flen);
611 dccp_sync_mss(newsk, dst_mtu(dst));
613 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
614 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
616 if (__inet_inherit_port(sk, newsk) < 0) {
620 __inet6_hash(newsk, NULL);
625 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
629 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
630 if (opt != NULL && opt != np->opt)
631 sock_kfree_s(sk, opt, opt->tot_len);
635 /* The socket must have it's spinlock held when we get
638 * We have a potential double-lock case here, so even when
639 * doing backlog processing we use the BH locking scheme.
640 * This is because we cannot sleep with the original spinlock
643 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
645 struct ipv6_pinfo *np = inet6_sk(sk);
646 struct sk_buff *opt_skb = NULL;
648 /* Imagine: socket is IPv6. IPv4 packet arrives,
649 goes to IPv4 receive handler and backlogged.
650 From backlog it always goes here. Kerboom...
651 Fortunately, dccp_rcv_established and rcv_established
652 handle them correctly, but it is not case with
653 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
656 if (skb->protocol == htons(ETH_P_IP))
657 return dccp_v4_do_rcv(sk, skb);
659 if (sk_filter(sk, skb))
663 * socket locking is here for SMP purposes as backlog rcv is currently
664 * called with bh processing disabled.
667 /* Do Stevens' IPV6_PKTOPTIONS.
669 Yes, guys, it is the only place in our code, where we
670 may make it not affecting IPv4.
671 The rest of code is protocol independent,
672 and I do not like idea to uglify IPv4.
674 Actually, all the idea behind IPV6_PKTOPTIONS
675 looks not very well thought. For now we latch
676 options, received in the last packet, enqueued
677 by tcp. Feel free to propose better solution.
682 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
683 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
685 opt_skb = skb_clone(skb, GFP_ATOMIC);
687 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
688 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
691 /* XXX This is where we would goto ipv6_pktoptions. */
692 __kfree_skb(opt_skb);
698 * Step 3: Process LISTEN state
699 * If S.state == LISTEN,
700 * If P.type == Request or P contains a valid Init Cookie option,
701 * (* Must scan the packet's options to check for Init
702 * Cookies. Only Init Cookies are processed here,
703 * however; other options are processed in Step 8. This
704 * scan need only be performed if the endpoint uses Init
706 * (* Generate a new socket and switch to that socket *)
707 * Set S := new socket for this port pair
709 * Choose S.ISS (initial seqno) or set from Init Cookies
710 * Initialize S.GAR := S.ISS
711 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
712 * Continue with S.state == RESPOND
713 * (* A Response packet will be generated in Step 11 *)
715 * Generate Reset(No Connection) unless P.type == Reset
716 * Drop packet and return
718 * NOTE: the check for the packet types is done in
719 * dccp_rcv_state_process
721 if (sk->sk_state == DCCP_LISTEN) {
722 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
727 * Queue it on the new socket if the new socket is active,
728 * otherwise we just shortcircuit this and continue with
732 if (dccp_child_process(sk, nsk, skb))
735 __kfree_skb(opt_skb);
740 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
743 /* XXX This is where we would goto ipv6_pktoptions. */
744 __kfree_skb(opt_skb);
749 dccp_v6_ctl_send_reset(sk, skb);
752 __kfree_skb(opt_skb);
757 static int dccp_v6_rcv(struct sk_buff *skb)
759 const struct dccp_hdr *dh;
763 /* Step 1: Check header basics */
765 if (dccp_invalid_packet(skb))
768 /* Step 1: If header checksum is incorrect, drop packet and return. */
769 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
770 &ipv6_hdr(skb)->daddr)) {
771 DCCP_WARN("dropped packet with invalid checksum\n");
777 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
778 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
780 if (dccp_packet_without_ack(skb))
781 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
783 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
786 * Look up flow ID in table and get corresponding socket */
787 sk = __inet6_lookup_skb(&dccp_hashinfo, skb,
788 dh->dccph_sport, dh->dccph_dport);
794 dccp_pr_debug("failed to look up flow ID in table and "
795 "get corresponding socket\n");
801 * ... or S.state == TIMEWAIT,
802 * Generate Reset(No Connection) unless P.type == Reset
803 * Drop packet and return
805 if (sk->sk_state == DCCP_TIME_WAIT) {
806 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
807 inet_twsk_put(inet_twsk(sk));
812 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
813 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
814 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
816 min_cov = dccp_sk(sk)->dccps_pcrlen;
817 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
818 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
819 dh->dccph_cscov, min_cov);
820 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
821 goto discard_and_relse;
824 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
825 goto discard_and_relse;
827 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
830 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
835 * Generate Reset(No Connection) unless P.type == Reset
836 * Drop packet and return
838 if (dh->dccph_type != DCCP_PKT_RESET) {
839 DCCP_SKB_CB(skb)->dccpd_reset_code =
840 DCCP_RESET_CODE_NO_CONNECTION;
841 dccp_v6_ctl_send_reset(sk, skb);
853 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
856 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
857 struct inet_connection_sock *icsk = inet_csk(sk);
858 struct inet_sock *inet = inet_sk(sk);
859 struct ipv6_pinfo *np = inet6_sk(sk);
860 struct dccp_sock *dp = dccp_sk(sk);
861 struct in6_addr *saddr = NULL, *final_p, final;
863 struct dst_entry *dst;
867 dp->dccps_role = DCCP_ROLE_CLIENT;
869 if (addr_len < SIN6_LEN_RFC2133)
872 if (usin->sin6_family != AF_INET6)
873 return -EAFNOSUPPORT;
875 memset(&fl6, 0, sizeof(fl6));
878 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
879 IP6_ECN_flow_init(fl6.flowlabel);
880 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
881 struct ip6_flowlabel *flowlabel;
882 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
883 if (flowlabel == NULL)
885 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
886 fl6_sock_release(flowlabel);
890 * connect() to INADDR_ANY means loopback (BSD'ism).
892 if (ipv6_addr_any(&usin->sin6_addr))
893 usin->sin6_addr.s6_addr[15] = 1;
895 addr_type = ipv6_addr_type(&usin->sin6_addr);
897 if (addr_type & IPV6_ADDR_MULTICAST)
900 if (addr_type & IPV6_ADDR_LINKLOCAL) {
901 if (addr_len >= sizeof(struct sockaddr_in6) &&
902 usin->sin6_scope_id) {
903 /* If interface is set while binding, indices
906 if (sk->sk_bound_dev_if &&
907 sk->sk_bound_dev_if != usin->sin6_scope_id)
910 sk->sk_bound_dev_if = usin->sin6_scope_id;
913 /* Connect to link-local address requires an interface */
914 if (!sk->sk_bound_dev_if)
918 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
919 np->flow_label = fl6.flowlabel;
924 if (addr_type == IPV6_ADDR_MAPPED) {
925 u32 exthdrlen = icsk->icsk_ext_hdr_len;
926 struct sockaddr_in sin;
928 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
930 if (__ipv6_only_sock(sk))
933 sin.sin_family = AF_INET;
934 sin.sin_port = usin->sin6_port;
935 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
937 icsk->icsk_af_ops = &dccp_ipv6_mapped;
938 sk->sk_backlog_rcv = dccp_v4_do_rcv;
940 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
942 icsk->icsk_ext_hdr_len = exthdrlen;
943 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
944 sk->sk_backlog_rcv = dccp_v6_do_rcv;
947 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
948 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &np->rcv_saddr);
953 if (!ipv6_addr_any(&np->rcv_saddr))
954 saddr = &np->rcv_saddr;
956 fl6.flowi6_proto = IPPROTO_DCCP;
957 ipv6_addr_copy(&fl6.daddr, &np->daddr);
958 ipv6_addr_copy(&fl6.saddr, saddr ? saddr : &np->saddr);
959 fl6.flowi6_oif = sk->sk_bound_dev_if;
960 fl6.fl6_dport = usin->sin6_port;
961 fl6.fl6_sport = inet->inet_sport;
962 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
964 final_p = fl6_update_dst(&fl6, np->opt, &final);
966 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
974 ipv6_addr_copy(&np->rcv_saddr, saddr);
977 /* set the source address */
978 ipv6_addr_copy(&np->saddr, saddr);
979 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
981 __ip6_dst_store(sk, dst, NULL, NULL);
983 icsk->icsk_ext_hdr_len = 0;
985 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
988 inet->inet_dport = usin->sin6_port;
990 dccp_set_state(sk, DCCP_REQUESTING);
991 err = inet6_hash_connect(&dccp_death_row, sk);
995 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
999 err = dccp_connect(sk);
1006 dccp_set_state(sk, DCCP_CLOSED);
1009 inet->inet_dport = 0;
1010 sk->sk_route_caps = 0;
1014 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1015 .queue_xmit = inet6_csk_xmit,
1016 .send_check = dccp_v6_send_check,
1017 .rebuild_header = inet6_sk_rebuild_header,
1018 .conn_request = dccp_v6_conn_request,
1019 .syn_recv_sock = dccp_v6_request_recv_sock,
1020 .net_header_len = sizeof(struct ipv6hdr),
1021 .setsockopt = ipv6_setsockopt,
1022 .getsockopt = ipv6_getsockopt,
1023 .addr2sockaddr = inet6_csk_addr2sockaddr,
1024 .sockaddr_len = sizeof(struct sockaddr_in6),
1025 .bind_conflict = inet6_csk_bind_conflict,
1026 #ifdef CONFIG_COMPAT
1027 .compat_setsockopt = compat_ipv6_setsockopt,
1028 .compat_getsockopt = compat_ipv6_getsockopt,
1033 * DCCP over IPv4 via INET6 API
1035 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1036 .queue_xmit = ip_queue_xmit,
1037 .send_check = dccp_v4_send_check,
1038 .rebuild_header = inet_sk_rebuild_header,
1039 .conn_request = dccp_v6_conn_request,
1040 .syn_recv_sock = dccp_v6_request_recv_sock,
1041 .net_header_len = sizeof(struct iphdr),
1042 .setsockopt = ipv6_setsockopt,
1043 .getsockopt = ipv6_getsockopt,
1044 .addr2sockaddr = inet6_csk_addr2sockaddr,
1045 .sockaddr_len = sizeof(struct sockaddr_in6),
1046 #ifdef CONFIG_COMPAT
1047 .compat_setsockopt = compat_ipv6_setsockopt,
1048 .compat_getsockopt = compat_ipv6_getsockopt,
1052 /* NOTE: A lot of things set to zero explicitly by call to
1053 * sk_alloc() so need not be done here.
1055 static int dccp_v6_init_sock(struct sock *sk)
1057 static __u8 dccp_v6_ctl_sock_initialized;
1058 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1061 if (unlikely(!dccp_v6_ctl_sock_initialized))
1062 dccp_v6_ctl_sock_initialized = 1;
1063 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1069 static void dccp_v6_destroy_sock(struct sock *sk)
1071 dccp_destroy_sock(sk);
1072 inet6_destroy_sock(sk);
1075 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1076 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1079 static struct proto dccp_v6_prot = {
1081 .owner = THIS_MODULE,
1082 .close = dccp_close,
1083 .connect = dccp_v6_connect,
1084 .disconnect = dccp_disconnect,
1085 .ioctl = dccp_ioctl,
1086 .init = dccp_v6_init_sock,
1087 .setsockopt = dccp_setsockopt,
1088 .getsockopt = dccp_getsockopt,
1089 .sendmsg = dccp_sendmsg,
1090 .recvmsg = dccp_recvmsg,
1091 .backlog_rcv = dccp_v6_do_rcv,
1092 .hash = dccp_v6_hash,
1093 .unhash = inet_unhash,
1094 .accept = inet_csk_accept,
1095 .get_port = inet_csk_get_port,
1096 .shutdown = dccp_shutdown,
1097 .destroy = dccp_v6_destroy_sock,
1098 .orphan_count = &dccp_orphan_count,
1099 .max_header = MAX_DCCP_HEADER,
1100 .obj_size = sizeof(struct dccp6_sock),
1101 .slab_flags = SLAB_DESTROY_BY_RCU,
1102 .rsk_prot = &dccp6_request_sock_ops,
1103 .twsk_prot = &dccp6_timewait_sock_ops,
1104 .h.hashinfo = &dccp_hashinfo,
1105 #ifdef CONFIG_COMPAT
1106 .compat_setsockopt = compat_dccp_setsockopt,
1107 .compat_getsockopt = compat_dccp_getsockopt,
1111 static const struct inet6_protocol dccp_v6_protocol = {
1112 .handler = dccp_v6_rcv,
1113 .err_handler = dccp_v6_err,
1114 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1117 static const struct proto_ops inet6_dccp_ops = {
1119 .owner = THIS_MODULE,
1120 .release = inet6_release,
1122 .connect = inet_stream_connect,
1123 .socketpair = sock_no_socketpair,
1124 .accept = inet_accept,
1125 .getname = inet6_getname,
1127 .ioctl = inet6_ioctl,
1128 .listen = inet_dccp_listen,
1129 .shutdown = inet_shutdown,
1130 .setsockopt = sock_common_setsockopt,
1131 .getsockopt = sock_common_getsockopt,
1132 .sendmsg = inet_sendmsg,
1133 .recvmsg = sock_common_recvmsg,
1134 .mmap = sock_no_mmap,
1135 .sendpage = sock_no_sendpage,
1136 #ifdef CONFIG_COMPAT
1137 .compat_setsockopt = compat_sock_common_setsockopt,
1138 .compat_getsockopt = compat_sock_common_getsockopt,
1142 static struct inet_protosw dccp_v6_protosw = {
1144 .protocol = IPPROTO_DCCP,
1145 .prot = &dccp_v6_prot,
1146 .ops = &inet6_dccp_ops,
1147 .flags = INET_PROTOSW_ICSK,
1150 static int __net_init dccp_v6_init_net(struct net *net)
1152 if (dccp_hashinfo.bhash == NULL)
1153 return -ESOCKTNOSUPPORT;
1155 return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6,
1156 SOCK_DCCP, IPPROTO_DCCP, net);
1159 static void __net_exit dccp_v6_exit_net(struct net *net)
1161 inet_ctl_sock_destroy(net->dccp.v6_ctl_sk);
1164 static struct pernet_operations dccp_v6_ops = {
1165 .init = dccp_v6_init_net,
1166 .exit = dccp_v6_exit_net,
1169 static int __init dccp_v6_init(void)
1171 int err = proto_register(&dccp_v6_prot, 1);
1176 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1178 goto out_unregister_proto;
1180 inet6_register_protosw(&dccp_v6_protosw);
1182 err = register_pernet_subsys(&dccp_v6_ops);
1184 goto out_destroy_ctl_sock;
1188 out_destroy_ctl_sock:
1189 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1190 inet6_unregister_protosw(&dccp_v6_protosw);
1191 out_unregister_proto:
1192 proto_unregister(&dccp_v6_prot);
1196 static void __exit dccp_v6_exit(void)
1198 unregister_pernet_subsys(&dccp_v6_ops);
1199 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1200 inet6_unregister_protosw(&dccp_v6_protosw);
1201 proto_unregister(&dccp_v6_prot);
1204 module_init(dccp_v6_init);
1205 module_exit(dccp_v6_exit);
1208 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1209 * values directly, Also cover the case where the protocol is not specified,
1210 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1212 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1213 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1214 MODULE_LICENSE("GPL");
1215 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1216 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");