1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * Linux INET6 implementation
6 * Based on net/dccp6/ipv6.c
8 * Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
11 #include <linux/module.h>
12 #include <linux/random.h>
13 #include <linux/slab.h>
14 #include <linux/xfrm.h>
15 #include <linux/string.h>
17 #include <net/addrconf.h>
18 #include <net/inet_common.h>
19 #include <net/inet_hashtables.h>
20 #include <net/inet_sock.h>
21 #include <net/inet6_connection_sock.h>
22 #include <net/inet6_hashtables.h>
23 #include <net/ip6_route.h>
25 #include <net/protocol.h>
26 #include <net/transp_v6.h>
27 #include <net/ip6_checksum.h>
29 #include <net/secure_seq.h>
30 #include <net/netns/generic.h>
37 struct dccp_v6_pernet {
38 struct sock *v6_ctl_sk;
41 static unsigned int dccp_v6_pernet_id __read_mostly;
43 /* The per-net v6_ctl_sk is used for sending RSTs and ACKs */
45 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped;
46 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
48 /* add pseudo-header to DCCP checksum stored in skb->csum */
49 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
50 const struct in6_addr *saddr,
51 const struct in6_addr *daddr)
53 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
56 static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
58 struct ipv6_pinfo *np = inet6_sk(sk);
59 struct dccp_hdr *dh = dccp_hdr(skb);
61 dccp_csum_outgoing(skb);
62 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr);
65 static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb)
67 return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
68 ipv6_hdr(skb)->saddr.s6_addr32,
69 dccp_hdr(skb)->dccph_dport,
70 dccp_hdr(skb)->dccph_sport );
74 static int dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
75 u8 type, u8 code, int offset, __be32 info)
77 const struct ipv6hdr *hdr;
78 const struct dccp_hdr *dh;
80 struct ipv6_pinfo *np;
84 struct net *net = dev_net(skb->dev);
86 if (!pskb_may_pull(skb, offset + sizeof(*dh)))
88 dh = (struct dccp_hdr *)(skb->data + offset);
89 if (!pskb_may_pull(skb, offset + __dccp_basic_hdr_len(dh)))
91 hdr = (const struct ipv6hdr *)skb->data;
92 dh = (struct dccp_hdr *)(skb->data + offset);
94 sk = __inet6_lookup_established(net, &dccp_hashinfo,
95 &hdr->daddr, dh->dccph_dport,
96 &hdr->saddr, ntohs(dh->dccph_sport),
100 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
105 if (sk->sk_state == DCCP_TIME_WAIT) {
106 inet_twsk_put(inet_twsk(sk));
109 seq = dccp_hdr_seq(dh);
110 if (sk->sk_state == DCCP_NEW_SYN_RECV) {
111 dccp_req_err(sk, seq);
116 if (sock_owned_by_user(sk))
117 __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
119 if (sk->sk_state == DCCP_CLOSED)
123 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
124 !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
125 __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
131 if (type == NDISC_REDIRECT) {
132 if (!sock_owned_by_user(sk)) {
133 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
136 dst->ops->redirect(dst, sk, skb);
141 if (type == ICMPV6_PKT_TOOBIG) {
142 struct dst_entry *dst = NULL;
144 if (!ip6_sk_accept_pmtu(sk))
147 if (sock_owned_by_user(sk))
149 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
152 dst = inet6_csk_update_pmtu(sk, ntohl(info));
156 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
157 dccp_sync_mss(sk, dst_mtu(dst));
161 icmpv6_err_convert(type, code, &err);
163 /* Might be for an request_sock */
164 switch (sk->sk_state) {
165 case DCCP_REQUESTING:
166 case DCCP_RESPOND: /* Cannot happen.
167 It can, it SYNs are crossed. --ANK */
168 if (!sock_owned_by_user(sk)) {
169 __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS);
172 * Wake people up to see the error
173 * (see connect in sock.c)
178 sk->sk_err_soft = err;
182 if (!sock_owned_by_user(sk) && np->recverr) {
186 sk->sk_err_soft = err;
195 static int dccp_v6_send_response(const struct sock *sk, struct request_sock *req)
197 struct inet_request_sock *ireq = inet_rsk(req);
198 struct ipv6_pinfo *np = inet6_sk(sk);
200 struct in6_addr *final_p, final;
203 struct dst_entry *dst;
205 memset(&fl6, 0, sizeof(fl6));
206 fl6.flowi6_proto = IPPROTO_DCCP;
207 fl6.daddr = ireq->ir_v6_rmt_addr;
208 fl6.saddr = ireq->ir_v6_loc_addr;
210 fl6.flowi6_oif = ireq->ir_iif;
211 fl6.fl6_dport = ireq->ir_rmt_port;
212 fl6.fl6_sport = htons(ireq->ir_num);
213 security_req_classify_flow(req, flowi6_to_flowi_common(&fl6));
217 final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt), &final);
220 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
227 skb = dccp_make_response(sk, dst, req);
229 struct dccp_hdr *dh = dccp_hdr(skb);
230 struct ipv6_txoptions *opt;
232 dh->dccph_checksum = dccp_v6_csum_finish(skb,
233 &ireq->ir_v6_loc_addr,
234 &ireq->ir_v6_rmt_addr);
235 fl6.daddr = ireq->ir_v6_rmt_addr;
237 opt = ireq->ipv6_opt;
239 opt = rcu_dereference(np->opt);
240 err = ip6_xmit(sk, skb, &fl6, READ_ONCE(sk->sk_mark), opt,
241 np->tclass, sk->sk_priority);
243 err = net_xmit_eval(err);
251 static void dccp_v6_reqsk_destructor(struct request_sock *req)
253 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
254 kfree(inet_rsk(req)->ipv6_opt);
255 kfree_skb(inet_rsk(req)->pktopts);
258 static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
260 const struct ipv6hdr *rxip6h;
263 struct net *net = dev_net(skb_dst(rxskb)->dev);
264 struct dccp_v6_pernet *pn;
266 struct dst_entry *dst;
268 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
271 if (!ipv6_unicast_destination(rxskb))
274 pn = net_generic(net, dccp_v6_pernet_id);
275 ctl_sk = pn->v6_ctl_sk;
276 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
280 rxip6h = ipv6_hdr(rxskb);
281 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
284 memset(&fl6, 0, sizeof(fl6));
285 fl6.daddr = rxip6h->saddr;
286 fl6.saddr = rxip6h->daddr;
288 fl6.flowi6_proto = IPPROTO_DCCP;
289 fl6.flowi6_oif = inet6_iif(rxskb);
290 fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
291 fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
292 security_skb_classify_flow(rxskb, flowi6_to_flowi_common(&fl6));
294 /* sk = NULL, but it is safe for now. RST socket required. */
295 dst = ip6_dst_lookup_flow(sock_net(ctl_sk), ctl_sk, &fl6, NULL);
297 skb_dst_set(skb, dst);
298 ip6_xmit(ctl_sk, skb, &fl6, 0, NULL, 0, 0);
299 DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
300 DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
307 static struct request_sock_ops dccp6_request_sock_ops = {
309 .obj_size = sizeof(struct dccp6_request_sock),
310 .rtx_syn_ack = dccp_v6_send_response,
311 .send_ack = dccp_reqsk_send_ack,
312 .destructor = dccp_v6_reqsk_destructor,
313 .send_reset = dccp_v6_ctl_send_reset,
314 .syn_ack_timeout = dccp_syn_ack_timeout,
317 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
319 struct request_sock *req;
320 struct dccp_request_sock *dreq;
321 struct inet_request_sock *ireq;
322 struct ipv6_pinfo *np = inet6_sk(sk);
323 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
324 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
326 if (skb->protocol == htons(ETH_P_IP))
327 return dccp_v4_conn_request(sk, skb);
329 if (!ipv6_unicast_destination(skb))
330 return 0; /* discard, don't send a reset here */
332 if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
333 __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
337 if (dccp_bad_service_code(sk, service)) {
338 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
342 * There are no SYN attacks on IPv6, yet...
344 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
345 if (inet_csk_reqsk_queue_is_full(sk))
348 if (sk_acceptq_is_full(sk))
351 req = inet_reqsk_alloc(&dccp6_request_sock_ops, sk, true);
355 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
358 dreq = dccp_rsk(req);
359 if (dccp_parse_options(sk, dreq, skb))
362 ireq = inet_rsk(req);
363 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
364 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
365 ireq->ireq_family = AF_INET6;
366 ireq->ir_mark = inet_request_mark(sk, skb);
368 if (security_inet_conn_request(sk, skb, req))
371 if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
372 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
373 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
374 refcount_inc(&skb->users);
377 ireq->ir_iif = READ_ONCE(sk->sk_bound_dev_if);
379 /* So that link locals have meaning */
381 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
382 ireq->ir_iif = inet6_iif(skb);
385 * Step 3: Process LISTEN state
387 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
389 * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
391 dreq->dreq_isr = dcb->dccpd_seq;
392 dreq->dreq_gsr = dreq->dreq_isr;
393 dreq->dreq_iss = dccp_v6_init_sequence(skb);
394 dreq->dreq_gss = dreq->dreq_iss;
395 dreq->dreq_service = service;
397 if (dccp_v6_send_response(sk, req))
400 inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
407 __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS);
411 static struct sock *dccp_v6_request_recv_sock(const struct sock *sk,
413 struct request_sock *req,
414 struct dst_entry *dst,
415 struct request_sock *req_unhash,
418 struct inet_request_sock *ireq = inet_rsk(req);
419 struct ipv6_pinfo *newnp;
420 const struct ipv6_pinfo *np = inet6_sk(sk);
421 struct ipv6_txoptions *opt;
422 struct inet_sock *newinet;
423 struct dccp6_sock *newdp6;
426 if (skb->protocol == htons(ETH_P_IP)) {
430 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst,
431 req_unhash, own_req);
435 newdp6 = (struct dccp6_sock *)newsk;
436 newinet = inet_sk(newsk);
437 newinet->pinet6 = &newdp6->inet6;
438 newnp = inet6_sk(newsk);
440 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
442 newnp->saddr = newsk->sk_v6_rcv_saddr;
444 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
445 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
446 newnp->pktoptions = NULL;
448 newnp->ipv6_mc_list = NULL;
449 newnp->ipv6_ac_list = NULL;
450 newnp->ipv6_fl_list = NULL;
451 newnp->mcast_oif = inet_iif(skb);
452 newnp->mcast_hops = ip_hdr(skb)->ttl;
455 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
456 * here, dccp_create_openreq_child now does this for us, see the comment in
457 * that function for the gory details. -acme
460 /* It is tricky place. Until this moment IPv4 tcp
461 worked with IPv6 icsk.icsk_af_ops.
464 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
470 if (sk_acceptq_is_full(sk))
476 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_DCCP);
481 newsk = dccp_create_openreq_child(sk, req, skb);
486 * No need to charge this sock to the relevant IPv6 refcnt debug socks
487 * count here, dccp_create_openreq_child now does this for us, see the
488 * comment in that function for the gory details. -acme
491 ip6_dst_store(newsk, dst, NULL, NULL);
492 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
494 newdp6 = (struct dccp6_sock *)newsk;
495 newinet = inet_sk(newsk);
496 newinet->pinet6 = &newdp6->inet6;
497 newnp = inet6_sk(newsk);
499 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
501 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr;
502 newnp->saddr = ireq->ir_v6_loc_addr;
503 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
504 newsk->sk_bound_dev_if = ireq->ir_iif;
506 /* Now IPv6 options...
508 First: no IPv4 options.
510 newinet->inet_opt = NULL;
513 newnp->rxopt.all = np->rxopt.all;
515 newnp->ipv6_mc_list = NULL;
516 newnp->ipv6_ac_list = NULL;
517 newnp->ipv6_fl_list = NULL;
518 newnp->pktoptions = NULL;
520 newnp->mcast_oif = inet6_iif(skb);
521 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
524 * Clone native IPv6 options from listening socket (if any)
526 * Yes, keeping reference count would be much more clever, but we make
527 * one more one thing there: reattach optmem to newsk.
529 opt = ireq->ipv6_opt;
531 opt = rcu_dereference(np->opt);
533 opt = ipv6_dup_options(newsk, opt);
534 RCU_INIT_POINTER(newnp->opt, opt);
536 inet_csk(newsk)->icsk_ext_hdr_len = 0;
538 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen +
541 dccp_sync_mss(newsk, dst_mtu(dst));
543 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
544 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
546 if (__inet_inherit_port(sk, newsk) < 0) {
547 inet_csk_prepare_forced_close(newsk);
551 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash), NULL);
552 /* Clone pktoptions received with SYN, if we own the req */
553 if (*own_req && ireq->pktopts) {
554 newnp->pktoptions = skb_clone_and_charge_r(ireq->pktopts, newsk);
555 consume_skb(ireq->pktopts);
556 ireq->pktopts = NULL;
562 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
566 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS);
570 /* The socket must have it's spinlock held when we get
573 * We have a potential double-lock case here, so even when
574 * doing backlog processing we use the BH locking scheme.
575 * This is because we cannot sleep with the original spinlock
578 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
580 struct ipv6_pinfo *np = inet6_sk(sk);
581 struct sk_buff *opt_skb = NULL;
583 /* Imagine: socket is IPv6. IPv4 packet arrives,
584 goes to IPv4 receive handler and backlogged.
585 From backlog it always goes here. Kerboom...
586 Fortunately, dccp_rcv_established and rcv_established
587 handle them correctly, but it is not case with
588 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
591 if (skb->protocol == htons(ETH_P_IP))
592 return dccp_v4_do_rcv(sk, skb);
594 if (sk_filter(sk, skb))
598 * socket locking is here for SMP purposes as backlog rcv is currently
599 * called with bh processing disabled.
602 /* Do Stevens' IPV6_PKTOPTIONS.
604 Yes, guys, it is the only place in our code, where we
605 may make it not affecting IPv4.
606 The rest of code is protocol independent,
607 and I do not like idea to uglify IPv4.
609 Actually, all the idea behind IPV6_PKTOPTIONS
610 looks not very well thought. For now we latch
611 options, received in the last packet, enqueued
612 by tcp. Feel free to propose better solution.
616 opt_skb = skb_clone_and_charge_r(skb, sk);
618 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
619 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
622 goto ipv6_pktoptions;
627 * Step 3: Process LISTEN state
628 * If S.state == LISTEN,
629 * If P.type == Request or P contains a valid Init Cookie option,
630 * (* Must scan the packet's options to check for Init
631 * Cookies. Only Init Cookies are processed here,
632 * however; other options are processed in Step 8. This
633 * scan need only be performed if the endpoint uses Init
635 * (* Generate a new socket and switch to that socket *)
636 * Set S := new socket for this port pair
638 * Choose S.ISS (initial seqno) or set from Init Cookies
639 * Initialize S.GAR := S.ISS
640 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
641 * Continue with S.state == RESPOND
642 * (* A Response packet will be generated in Step 11 *)
644 * Generate Reset(No Connection) unless P.type == Reset
645 * Drop packet and return
647 * NOTE: the check for the packet types is done in
648 * dccp_rcv_state_process
651 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
654 goto ipv6_pktoptions;
658 dccp_v6_ctl_send_reset(sk, skb);
661 __kfree_skb(opt_skb);
665 /* Handling IPV6_PKTOPTIONS skb the similar
666 * way it's done for net/ipv6/tcp_ipv6.c
669 if (!((1 << sk->sk_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) {
670 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
671 np->mcast_oif = inet6_iif(opt_skb);
672 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
673 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
674 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)
675 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
677 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
678 if (ipv6_opt_accepted(sk, opt_skb,
679 &DCCP_SKB_CB(opt_skb)->header.h6)) {
680 memmove(IP6CB(opt_skb),
681 &DCCP_SKB_CB(opt_skb)->header.h6,
682 sizeof(struct inet6_skb_parm));
683 opt_skb = xchg(&np->pktoptions, opt_skb);
685 __kfree_skb(opt_skb);
686 opt_skb = xchg(&np->pktoptions, NULL);
694 static int dccp_v6_rcv(struct sk_buff *skb)
696 const struct dccp_hdr *dh;
701 /* Step 1: Check header basics */
703 if (dccp_invalid_packet(skb))
706 /* Step 1: If header checksum is incorrect, drop packet and return. */
707 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
708 &ipv6_hdr(skb)->daddr)) {
709 DCCP_WARN("dropped packet with invalid checksum\n");
715 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
716 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
718 if (dccp_packet_without_ack(skb))
719 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
721 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
724 sk = __inet6_lookup_skb(&dccp_hashinfo, skb, __dccp_hdr_len(dh),
725 dh->dccph_sport, dh->dccph_dport,
726 inet6_iif(skb), 0, &refcounted);
728 dccp_pr_debug("failed to look up flow ID in table and "
729 "get corresponding socket\n");
735 * ... or S.state == TIMEWAIT,
736 * Generate Reset(No Connection) unless P.type == Reset
737 * Drop packet and return
739 if (sk->sk_state == DCCP_TIME_WAIT) {
740 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
741 inet_twsk_put(inet_twsk(sk));
745 if (sk->sk_state == DCCP_NEW_SYN_RECV) {
746 struct request_sock *req = inet_reqsk(sk);
749 sk = req->rsk_listener;
750 if (unlikely(sk->sk_state != DCCP_LISTEN)) {
751 inet_csk_reqsk_queue_drop_and_put(sk, req);
756 nsk = dccp_check_req(sk, skb, req);
759 goto discard_and_relse;
763 } else if (dccp_child_process(sk, nsk, skb)) {
764 dccp_v6_ctl_send_reset(sk, skb);
765 goto discard_and_relse;
772 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
773 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
774 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
776 min_cov = dccp_sk(sk)->dccps_pcrlen;
777 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
778 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
779 dh->dccph_cscov, min_cov);
780 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
781 goto discard_and_relse;
784 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
785 goto discard_and_relse;
788 return __sk_receive_skb(sk, skb, 1, dh->dccph_doff * 4,
789 refcounted) ? -1 : 0;
792 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
797 * Generate Reset(No Connection) unless P.type == Reset
798 * Drop packet and return
800 if (dh->dccph_type != DCCP_PKT_RESET) {
801 DCCP_SKB_CB(skb)->dccpd_reset_code =
802 DCCP_RESET_CODE_NO_CONNECTION;
803 dccp_v6_ctl_send_reset(sk, skb);
816 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
819 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
820 struct inet_connection_sock *icsk = inet_csk(sk);
821 struct inet_sock *inet = inet_sk(sk);
822 struct ipv6_pinfo *np = inet6_sk(sk);
823 struct dccp_sock *dp = dccp_sk(sk);
824 struct in6_addr *saddr = NULL, *final_p, final;
825 struct ipv6_txoptions *opt;
827 struct dst_entry *dst;
831 dp->dccps_role = DCCP_ROLE_CLIENT;
833 if (addr_len < SIN6_LEN_RFC2133)
836 if (usin->sin6_family != AF_INET6)
837 return -EAFNOSUPPORT;
839 memset(&fl6, 0, sizeof(fl6));
842 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
843 IP6_ECN_flow_init(fl6.flowlabel);
844 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
845 struct ip6_flowlabel *flowlabel;
846 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
847 if (IS_ERR(flowlabel))
849 fl6_sock_release(flowlabel);
853 * connect() to INADDR_ANY means loopback (BSD'ism).
855 if (ipv6_addr_any(&usin->sin6_addr))
856 usin->sin6_addr.s6_addr[15] = 1;
858 addr_type = ipv6_addr_type(&usin->sin6_addr);
860 if (addr_type & IPV6_ADDR_MULTICAST)
863 if (addr_type & IPV6_ADDR_LINKLOCAL) {
864 if (addr_len >= sizeof(struct sockaddr_in6) &&
865 usin->sin6_scope_id) {
866 /* If interface is set while binding, indices
869 if (sk->sk_bound_dev_if &&
870 sk->sk_bound_dev_if != usin->sin6_scope_id)
873 sk->sk_bound_dev_if = usin->sin6_scope_id;
876 /* Connect to link-local address requires an interface */
877 if (!sk->sk_bound_dev_if)
881 sk->sk_v6_daddr = usin->sin6_addr;
882 np->flow_label = fl6.flowlabel;
887 if (addr_type == IPV6_ADDR_MAPPED) {
888 u32 exthdrlen = icsk->icsk_ext_hdr_len;
889 struct sockaddr_in sin;
891 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
893 if (ipv6_only_sock(sk))
896 sin.sin_family = AF_INET;
897 sin.sin_port = usin->sin6_port;
898 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
900 icsk->icsk_af_ops = &dccp_ipv6_mapped;
901 sk->sk_backlog_rcv = dccp_v4_do_rcv;
903 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
905 icsk->icsk_ext_hdr_len = exthdrlen;
906 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
907 sk->sk_backlog_rcv = dccp_v6_do_rcv;
910 np->saddr = sk->sk_v6_rcv_saddr;
914 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr))
915 saddr = &sk->sk_v6_rcv_saddr;
917 fl6.flowi6_proto = IPPROTO_DCCP;
918 fl6.daddr = sk->sk_v6_daddr;
919 fl6.saddr = saddr ? *saddr : np->saddr;
920 fl6.flowi6_oif = sk->sk_bound_dev_if;
921 fl6.fl6_dport = usin->sin6_port;
922 fl6.fl6_sport = inet->inet_sport;
923 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
925 opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
926 final_p = fl6_update_dst(&fl6, opt, &final);
928 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
937 err = inet_bhash2_update_saddr(sk, saddr, AF_INET6);
942 /* set the source address */
944 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
946 ip6_dst_store(sk, dst, NULL, NULL);
948 icsk->icsk_ext_hdr_len = 0;
950 icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
952 inet->inet_dport = usin->sin6_port;
954 dccp_set_state(sk, DCCP_REQUESTING);
955 err = inet6_hash_connect(&dccp_death_row, sk);
959 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
960 sk->sk_v6_daddr.s6_addr32,
963 err = dccp_connect(sk);
970 dccp_set_state(sk, DCCP_CLOSED);
971 inet_bhash2_reset_saddr(sk);
974 inet->inet_dport = 0;
975 sk->sk_route_caps = 0;
979 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
980 .queue_xmit = inet6_csk_xmit,
981 .send_check = dccp_v6_send_check,
982 .rebuild_header = inet6_sk_rebuild_header,
983 .conn_request = dccp_v6_conn_request,
984 .syn_recv_sock = dccp_v6_request_recv_sock,
985 .net_header_len = sizeof(struct ipv6hdr),
986 .setsockopt = ipv6_setsockopt,
987 .getsockopt = ipv6_getsockopt,
988 .addr2sockaddr = inet6_csk_addr2sockaddr,
989 .sockaddr_len = sizeof(struct sockaddr_in6),
993 * DCCP over IPv4 via INET6 API
995 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
996 .queue_xmit = ip_queue_xmit,
997 .send_check = dccp_v4_send_check,
998 .rebuild_header = inet_sk_rebuild_header,
999 .conn_request = dccp_v6_conn_request,
1000 .syn_recv_sock = dccp_v6_request_recv_sock,
1001 .net_header_len = sizeof(struct iphdr),
1002 .setsockopt = ipv6_setsockopt,
1003 .getsockopt = ipv6_getsockopt,
1004 .addr2sockaddr = inet6_csk_addr2sockaddr,
1005 .sockaddr_len = sizeof(struct sockaddr_in6),
1008 static void dccp_v6_sk_destruct(struct sock *sk)
1010 dccp_destruct_common(sk);
1011 inet6_sock_destruct(sk);
1014 /* NOTE: A lot of things set to zero explicitly by call to
1015 * sk_alloc() so need not be done here.
1017 static int dccp_v6_init_sock(struct sock *sk)
1019 static __u8 dccp_v6_ctl_sock_initialized;
1020 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1023 if (unlikely(!dccp_v6_ctl_sock_initialized))
1024 dccp_v6_ctl_sock_initialized = 1;
1025 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1026 sk->sk_destruct = dccp_v6_sk_destruct;
1032 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1033 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1036 static struct proto dccp_v6_prot = {
1038 .owner = THIS_MODULE,
1039 .close = dccp_close,
1040 .connect = dccp_v6_connect,
1041 .disconnect = dccp_disconnect,
1042 .ioctl = dccp_ioctl,
1043 .init = dccp_v6_init_sock,
1044 .setsockopt = dccp_setsockopt,
1045 .getsockopt = dccp_getsockopt,
1046 .sendmsg = dccp_sendmsg,
1047 .recvmsg = dccp_recvmsg,
1048 .backlog_rcv = dccp_v6_do_rcv,
1050 .unhash = inet_unhash,
1051 .accept = inet_csk_accept,
1052 .get_port = inet_csk_get_port,
1053 .shutdown = dccp_shutdown,
1054 .destroy = dccp_destroy_sock,
1055 .orphan_count = &dccp_orphan_count,
1056 .max_header = MAX_DCCP_HEADER,
1057 .obj_size = sizeof(struct dccp6_sock),
1058 .slab_flags = SLAB_TYPESAFE_BY_RCU,
1059 .rsk_prot = &dccp6_request_sock_ops,
1060 .twsk_prot = &dccp6_timewait_sock_ops,
1061 .h.hashinfo = &dccp_hashinfo,
1064 static const struct inet6_protocol dccp_v6_protocol = {
1065 .handler = dccp_v6_rcv,
1066 .err_handler = dccp_v6_err,
1067 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1070 static const struct proto_ops inet6_dccp_ops = {
1072 .owner = THIS_MODULE,
1073 .release = inet6_release,
1075 .connect = inet_stream_connect,
1076 .socketpair = sock_no_socketpair,
1077 .accept = inet_accept,
1078 .getname = inet6_getname,
1080 .ioctl = inet6_ioctl,
1081 .gettstamp = sock_gettstamp,
1082 .listen = inet_dccp_listen,
1083 .shutdown = inet_shutdown,
1084 .setsockopt = sock_common_setsockopt,
1085 .getsockopt = sock_common_getsockopt,
1086 .sendmsg = inet_sendmsg,
1087 .recvmsg = sock_common_recvmsg,
1088 .mmap = sock_no_mmap,
1089 .sendpage = sock_no_sendpage,
1090 #ifdef CONFIG_COMPAT
1091 .compat_ioctl = inet6_compat_ioctl,
1095 static struct inet_protosw dccp_v6_protosw = {
1097 .protocol = IPPROTO_DCCP,
1098 .prot = &dccp_v6_prot,
1099 .ops = &inet6_dccp_ops,
1100 .flags = INET_PROTOSW_ICSK,
1103 static int __net_init dccp_v6_init_net(struct net *net)
1105 struct dccp_v6_pernet *pn = net_generic(net, dccp_v6_pernet_id);
1107 if (dccp_hashinfo.bhash == NULL)
1108 return -ESOCKTNOSUPPORT;
1110 return inet_ctl_sock_create(&pn->v6_ctl_sk, PF_INET6,
1111 SOCK_DCCP, IPPROTO_DCCP, net);
1114 static void __net_exit dccp_v6_exit_net(struct net *net)
1116 struct dccp_v6_pernet *pn = net_generic(net, dccp_v6_pernet_id);
1118 inet_ctl_sock_destroy(pn->v6_ctl_sk);
1121 static void __net_exit dccp_v6_exit_batch(struct list_head *net_exit_list)
1123 inet_twsk_purge(&dccp_hashinfo, AF_INET6);
1126 static struct pernet_operations dccp_v6_ops = {
1127 .init = dccp_v6_init_net,
1128 .exit = dccp_v6_exit_net,
1129 .exit_batch = dccp_v6_exit_batch,
1130 .id = &dccp_v6_pernet_id,
1131 .size = sizeof(struct dccp_v6_pernet),
1134 static int __init dccp_v6_init(void)
1136 int err = proto_register(&dccp_v6_prot, 1);
1141 inet6_register_protosw(&dccp_v6_protosw);
1143 err = register_pernet_subsys(&dccp_v6_ops);
1145 goto out_destroy_ctl_sock;
1147 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1149 goto out_unregister_proto;
1153 out_unregister_proto:
1154 unregister_pernet_subsys(&dccp_v6_ops);
1155 out_destroy_ctl_sock:
1156 inet6_unregister_protosw(&dccp_v6_protosw);
1157 proto_unregister(&dccp_v6_prot);
1161 static void __exit dccp_v6_exit(void)
1163 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1164 unregister_pernet_subsys(&dccp_v6_ops);
1165 inet6_unregister_protosw(&dccp_v6_protosw);
1166 proto_unregister(&dccp_v6_prot);
1169 module_init(dccp_v6_init);
1170 module_exit(dccp_v6_exit);
1173 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1174 * values directly, Also cover the case where the protocol is not specified,
1175 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1177 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1178 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1179 MODULE_LICENSE("GPL");
1180 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1181 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");