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 dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
305 struct ipv6hdr *rxip6h;
306 const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
307 sizeof(struct dccp_hdr_ext) +
308 sizeof(struct dccp_hdr_reset);
313 if (rxdh->dccph_type == DCCP_PKT_RESET)
316 if (!ipv6_unicast_destination(rxskb))
319 skb = alloc_skb(dccp_v6_ctl_socket->sk->sk_prot->max_header,
324 skb_reserve(skb, dccp_v6_ctl_socket->sk->sk_prot->max_header);
326 dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len);
328 /* Swap the send and the receive. */
329 dh->dccph_type = DCCP_PKT_RESET;
330 dh->dccph_sport = rxdh->dccph_dport;
331 dh->dccph_dport = rxdh->dccph_sport;
332 dh->dccph_doff = dccp_hdr_reset_len / 4;
334 dccp_hdr_reset(skb)->dccph_reset_code =
335 DCCP_SKB_CB(rxskb)->dccpd_reset_code;
337 /* See "8.3.1. Abnormal Termination" in RFC 4340 */
338 if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
339 dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
341 dccp_hdr_set_seq(dh, seqno);
342 dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq);
344 dccp_csum_outgoing(skb);
345 rxip6h = ipv6_hdr(rxskb);
346 dh->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
349 memset(&fl, 0, sizeof(fl));
350 ipv6_addr_copy(&fl.fl6_dst, &rxip6h->saddr);
351 ipv6_addr_copy(&fl.fl6_src, &rxip6h->daddr);
353 fl.proto = IPPROTO_DCCP;
354 fl.oif = inet6_iif(rxskb);
355 fl.fl_ip_dport = dh->dccph_dport;
356 fl.fl_ip_sport = dh->dccph_sport;
357 security_skb_classify_flow(rxskb, &fl);
359 /* sk = NULL, but it is safe for now. RST socket required. */
360 if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) {
361 if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) {
362 ip6_xmit(dccp_v6_ctl_socket->sk, skb, &fl, NULL, 0);
363 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
364 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
372 static struct request_sock_ops dccp6_request_sock_ops = {
374 .obj_size = sizeof(struct dccp6_request_sock),
375 .rtx_syn_ack = dccp_v6_send_response,
376 .send_ack = dccp_reqsk_send_ack,
377 .destructor = dccp_v6_reqsk_destructor,
378 .send_reset = dccp_v6_ctl_send_reset,
381 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
383 const struct dccp_hdr *dh = dccp_hdr(skb);
384 const struct ipv6hdr *iph = ipv6_hdr(skb);
386 struct request_sock **prev;
387 /* Find possible connection requests. */
388 struct request_sock *req = inet6_csk_search_req(sk, &prev,
394 return dccp_check_req(sk, skb, req, prev);
396 nsk = __inet6_lookup_established(&dccp_hashinfo,
397 &iph->saddr, dh->dccph_sport,
398 &iph->daddr, ntohs(dh->dccph_dport),
401 if (nsk->sk_state != DCCP_TIME_WAIT) {
405 inet_twsk_put(inet_twsk(nsk));
412 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
414 struct request_sock *req;
415 struct dccp_request_sock *dreq;
416 struct inet6_request_sock *ireq6;
417 struct ipv6_pinfo *np = inet6_sk(sk);
418 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
419 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
420 __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
422 if (skb->protocol == htons(ETH_P_IP))
423 return dccp_v4_conn_request(sk, skb);
425 if (!ipv6_unicast_destination(skb))
428 if (dccp_bad_service_code(sk, service)) {
429 reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
433 * There are no SYN attacks on IPv6, yet...
435 if (inet_csk_reqsk_queue_is_full(sk))
438 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
441 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
445 if (dccp_parse_options(sk, skb))
448 dccp_reqsk_init(req, skb);
450 if (security_inet_conn_request(sk, skb, req))
453 ireq6 = inet6_rsk(req);
454 ipv6_addr_copy(&ireq6->rmt_addr, &ipv6_hdr(skb)->saddr);
455 ipv6_addr_copy(&ireq6->loc_addr, &ipv6_hdr(skb)->daddr);
456 ireq6->pktopts = NULL;
458 if (ipv6_opt_accepted(sk, skb) ||
459 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
460 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
461 atomic_inc(&skb->users);
462 ireq6->pktopts = skb;
464 ireq6->iif = sk->sk_bound_dev_if;
466 /* So that link locals have meaning */
467 if (!sk->sk_bound_dev_if &&
468 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
469 ireq6->iif = inet6_iif(skb);
472 * Step 3: Process LISTEN state
474 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
476 * In fact we defer setting S.GSR, S.SWL, S.SWH to
477 * dccp_create_openreq_child.
479 dreq = dccp_rsk(req);
480 dreq->dreq_isr = dcb->dccpd_seq;
481 dreq->dreq_iss = dccp_v6_init_sequence(skb);
482 dreq->dreq_service = service;
484 if (dccp_v6_send_response(sk, req, NULL))
487 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
493 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
494 dcb->dccpd_reset_code = reset_code;
498 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
500 struct request_sock *req,
501 struct dst_entry *dst)
503 struct inet6_request_sock *ireq6 = inet6_rsk(req);
504 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
505 struct inet_sock *newinet;
506 struct dccp_sock *newdp;
507 struct dccp6_sock *newdp6;
509 struct ipv6_txoptions *opt;
511 if (skb->protocol == htons(ETH_P_IP)) {
515 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
519 newdp6 = (struct dccp6_sock *)newsk;
520 newdp = dccp_sk(newsk);
521 newinet = inet_sk(newsk);
522 newinet->pinet6 = &newdp6->inet6;
523 newnp = inet6_sk(newsk);
525 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
527 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
530 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
533 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
535 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
536 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
537 newnp->pktoptions = NULL;
539 newnp->mcast_oif = inet6_iif(skb);
540 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
543 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
544 * here, dccp_create_openreq_child now does this for us, see the comment in
545 * that function for the gory details. -acme
548 /* It is tricky place. Until this moment IPv4 tcp
549 worked with IPv6 icsk.icsk_af_ops.
552 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
559 if (sk_acceptq_is_full(sk))
563 struct in6_addr *final_p = NULL, final;
566 memset(&fl, 0, sizeof(fl));
567 fl.proto = IPPROTO_DCCP;
568 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
569 if (opt != NULL && opt->srcrt != NULL) {
570 const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
572 ipv6_addr_copy(&final, &fl.fl6_dst);
573 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
576 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
577 fl.oif = sk->sk_bound_dev_if;
578 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
579 fl.fl_ip_sport = inet_sk(sk)->sport;
580 security_sk_classify_flow(sk, &fl);
582 if (ip6_dst_lookup(sk, &dst, &fl))
586 ipv6_addr_copy(&fl.fl6_dst, final_p);
588 if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
592 newsk = dccp_create_openreq_child(sk, req, skb);
597 * No need to charge this sock to the relevant IPv6 refcnt debug socks
598 * count here, dccp_create_openreq_child now does this for us, see the
599 * comment in that function for the gory details. -acme
602 __ip6_dst_store(newsk, dst, NULL, NULL);
603 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
605 newdp6 = (struct dccp6_sock *)newsk;
606 newinet = inet_sk(newsk);
607 newinet->pinet6 = &newdp6->inet6;
608 newdp = dccp_sk(newsk);
609 newnp = inet6_sk(newsk);
611 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
613 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
614 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
615 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
616 newsk->sk_bound_dev_if = ireq6->iif;
618 /* Now IPv6 options...
620 First: no IPv4 options.
625 newnp->rxopt.all = np->rxopt.all;
627 /* Clone pktoptions received with SYN */
628 newnp->pktoptions = NULL;
629 if (ireq6->pktopts != NULL) {
630 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
631 kfree_skb(ireq6->pktopts);
632 ireq6->pktopts = NULL;
633 if (newnp->pktoptions)
634 skb_set_owner_r(newnp->pktoptions, newsk);
637 newnp->mcast_oif = inet6_iif(skb);
638 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
641 * Clone native IPv6 options from listening socket (if any)
643 * Yes, keeping reference count would be much more clever, but we make
644 * one more one thing there: reattach optmem to newsk.
647 newnp->opt = ipv6_dup_options(newsk, opt);
649 sock_kfree_s(sk, opt, opt->tot_len);
652 inet_csk(newsk)->icsk_ext_hdr_len = 0;
653 if (newnp->opt != NULL)
654 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
655 newnp->opt->opt_flen);
657 dccp_sync_mss(newsk, dst_mtu(dst));
659 newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
661 __inet6_hash(&dccp_hashinfo, newsk);
662 inet_inherit_port(&dccp_hashinfo, sk, newsk);
667 NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
669 NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
670 if (opt != NULL && opt != np->opt)
671 sock_kfree_s(sk, opt, opt->tot_len);
676 /* The socket must have it's spinlock held when we get
679 * We have a potential double-lock case here, so even when
680 * doing backlog processing we use the BH locking scheme.
681 * This is because we cannot sleep with the original spinlock
684 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
686 struct ipv6_pinfo *np = inet6_sk(sk);
687 struct sk_buff *opt_skb = NULL;
689 /* Imagine: socket is IPv6. IPv4 packet arrives,
690 goes to IPv4 receive handler and backlogged.
691 From backlog it always goes here. Kerboom...
692 Fortunately, dccp_rcv_established and rcv_established
693 handle them correctly, but it is not case with
694 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
697 if (skb->protocol == htons(ETH_P_IP))
698 return dccp_v4_do_rcv(sk, skb);
700 if (sk_filter(sk, skb))
704 * socket locking is here for SMP purposes as backlog rcv is currently
705 * called with bh processing disabled.
708 /* Do Stevens' IPV6_PKTOPTIONS.
710 Yes, guys, it is the only place in our code, where we
711 may make it not affecting IPv4.
712 The rest of code is protocol independent,
713 and I do not like idea to uglify IPv4.
715 Actually, all the idea behind IPV6_PKTOPTIONS
716 looks not very well thought. For now we latch
717 options, received in the last packet, enqueued
718 by tcp. Feel free to propose better solution.
723 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
724 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
726 opt_skb = skb_clone(skb, GFP_ATOMIC);
728 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
729 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
732 /* XXX This is where we would goto ipv6_pktoptions. */
733 __kfree_skb(opt_skb);
739 * Step 3: Process LISTEN state
740 * If S.state == LISTEN,
741 * If P.type == Request or P contains a valid Init Cookie option,
742 * (* Must scan the packet's options to check for Init
743 * Cookies. Only Init Cookies are processed here,
744 * however; other options are processed in Step 8. This
745 * scan need only be performed if the endpoint uses Init
747 * (* Generate a new socket and switch to that socket *)
748 * Set S := new socket for this port pair
750 * Choose S.ISS (initial seqno) or set from Init Cookies
751 * Initialize S.GAR := S.ISS
752 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
753 * Continue with S.state == RESPOND
754 * (* A Response packet will be generated in Step 11 *)
756 * Generate Reset(No Connection) unless P.type == Reset
757 * Drop packet and return
759 * NOTE: the check for the packet types is done in
760 * dccp_rcv_state_process
762 if (sk->sk_state == DCCP_LISTEN) {
763 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
768 * Queue it on the new socket if the new socket is active,
769 * otherwise we just shortcircuit this and continue with
773 if (dccp_child_process(sk, nsk, skb))
776 __kfree_skb(opt_skb);
781 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
784 /* XXX This is where we would goto ipv6_pktoptions. */
785 __kfree_skb(opt_skb);
790 dccp_v6_ctl_send_reset(sk, skb);
793 __kfree_skb(opt_skb);
798 static int dccp_v6_rcv(struct sk_buff **pskb)
800 const struct dccp_hdr *dh;
801 struct sk_buff *skb = *pskb;
805 /* Step 1: Check header basics */
807 if (dccp_invalid_packet(skb))
810 /* Step 1: If header checksum is incorrect, drop packet and return. */
811 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
812 &ipv6_hdr(skb)->daddr)) {
813 DCCP_WARN("dropped packet with invalid checksum\n");
819 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
820 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
822 if (dccp_packet_without_ack(skb))
823 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
825 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
828 * Look up flow ID in table and get corresponding socket */
829 sk = __inet6_lookup(&dccp_hashinfo, &ipv6_hdr(skb)->saddr,
831 &ipv6_hdr(skb)->daddr, ntohs(dh->dccph_dport),
838 dccp_pr_debug("failed to look up flow ID in table and "
839 "get corresponding socket\n");
845 * ... or S.state == TIMEWAIT,
846 * Generate Reset(No Connection) unless P.type == Reset
847 * Drop packet and return
849 if (sk->sk_state == DCCP_TIME_WAIT) {
850 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
851 inet_twsk_put(inet_twsk(sk));
856 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
857 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
858 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
860 min_cov = dccp_sk(sk)->dccps_pcrlen;
861 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
862 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
863 dh->dccph_cscov, min_cov);
864 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
865 goto discard_and_relse;
868 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
869 goto discard_and_relse;
871 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
874 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
879 * Generate Reset(No Connection) unless P.type == Reset
880 * Drop packet and return
882 if (dh->dccph_type != DCCP_PKT_RESET) {
883 DCCP_SKB_CB(skb)->dccpd_reset_code =
884 DCCP_RESET_CODE_NO_CONNECTION;
885 dccp_v6_ctl_send_reset(sk, skb);
897 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
900 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
901 struct inet_connection_sock *icsk = inet_csk(sk);
902 struct inet_sock *inet = inet_sk(sk);
903 struct ipv6_pinfo *np = inet6_sk(sk);
904 struct dccp_sock *dp = dccp_sk(sk);
905 struct in6_addr *saddr = NULL, *final_p = NULL, final;
907 struct dst_entry *dst;
911 dp->dccps_role = DCCP_ROLE_CLIENT;
913 if (addr_len < SIN6_LEN_RFC2133)
916 if (usin->sin6_family != AF_INET6)
917 return -EAFNOSUPPORT;
919 memset(&fl, 0, sizeof(fl));
922 fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
923 IP6_ECN_flow_init(fl.fl6_flowlabel);
924 if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) {
925 struct ip6_flowlabel *flowlabel;
926 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
927 if (flowlabel == NULL)
929 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
930 fl6_sock_release(flowlabel);
934 * connect() to INADDR_ANY means loopback (BSD'ism).
936 if (ipv6_addr_any(&usin->sin6_addr))
937 usin->sin6_addr.s6_addr[15] = 1;
939 addr_type = ipv6_addr_type(&usin->sin6_addr);
941 if (addr_type & IPV6_ADDR_MULTICAST)
944 if (addr_type & IPV6_ADDR_LINKLOCAL) {
945 if (addr_len >= sizeof(struct sockaddr_in6) &&
946 usin->sin6_scope_id) {
947 /* If interface is set while binding, indices
950 if (sk->sk_bound_dev_if &&
951 sk->sk_bound_dev_if != usin->sin6_scope_id)
954 sk->sk_bound_dev_if = usin->sin6_scope_id;
957 /* Connect to link-local address requires an interface */
958 if (!sk->sk_bound_dev_if)
962 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
963 np->flow_label = fl.fl6_flowlabel;
968 if (addr_type == IPV6_ADDR_MAPPED) {
969 u32 exthdrlen = icsk->icsk_ext_hdr_len;
970 struct sockaddr_in sin;
972 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
974 if (__ipv6_only_sock(sk))
977 sin.sin_family = AF_INET;
978 sin.sin_port = usin->sin6_port;
979 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
981 icsk->icsk_af_ops = &dccp_ipv6_mapped;
982 sk->sk_backlog_rcv = dccp_v4_do_rcv;
984 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
986 icsk->icsk_ext_hdr_len = exthdrlen;
987 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
988 sk->sk_backlog_rcv = dccp_v6_do_rcv;
991 ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
993 ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
1000 if (!ipv6_addr_any(&np->rcv_saddr))
1001 saddr = &np->rcv_saddr;
1003 fl.proto = IPPROTO_DCCP;
1004 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1005 ipv6_addr_copy(&fl.fl6_src, saddr ? saddr : &np->saddr);
1006 fl.oif = sk->sk_bound_dev_if;
1007 fl.fl_ip_dport = usin->sin6_port;
1008 fl.fl_ip_sport = inet->sport;
1009 security_sk_classify_flow(sk, &fl);
1011 if (np->opt != NULL && np->opt->srcrt != NULL) {
1012 const struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
1014 ipv6_addr_copy(&final, &fl.fl6_dst);
1015 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1019 err = ip6_dst_lookup(sk, &dst, &fl);
1024 ipv6_addr_copy(&fl.fl6_dst, final_p);
1026 err = __xfrm_lookup(&dst, &fl, sk, 1);
1028 if (err == -EREMOTE)
1029 err = ip6_dst_blackhole(sk, &dst, &fl);
1034 if (saddr == NULL) {
1035 saddr = &fl.fl6_src;
1036 ipv6_addr_copy(&np->rcv_saddr, saddr);
1039 /* set the source address */
1040 ipv6_addr_copy(&np->saddr, saddr);
1041 inet->rcv_saddr = LOOPBACK4_IPV6;
1043 __ip6_dst_store(sk, dst, NULL, NULL);
1045 icsk->icsk_ext_hdr_len = 0;
1046 if (np->opt != NULL)
1047 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
1048 np->opt->opt_nflen);
1050 inet->dport = usin->sin6_port;
1052 dccp_set_state(sk, DCCP_REQUESTING);
1053 err = inet6_hash_connect(&dccp_death_row, sk);
1057 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
1058 np->daddr.s6_addr32,
1059 inet->sport, inet->dport);
1060 err = dccp_connect(sk);
1067 dccp_set_state(sk, DCCP_CLOSED);
1071 sk->sk_route_caps = 0;
1075 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1076 .queue_xmit = inet6_csk_xmit,
1077 .send_check = dccp_v6_send_check,
1078 .rebuild_header = inet6_sk_rebuild_header,
1079 .conn_request = dccp_v6_conn_request,
1080 .syn_recv_sock = dccp_v6_request_recv_sock,
1081 .net_header_len = sizeof(struct ipv6hdr),
1082 .setsockopt = ipv6_setsockopt,
1083 .getsockopt = ipv6_getsockopt,
1084 .addr2sockaddr = inet6_csk_addr2sockaddr,
1085 .sockaddr_len = sizeof(struct sockaddr_in6),
1086 #ifdef CONFIG_COMPAT
1087 .compat_setsockopt = compat_ipv6_setsockopt,
1088 .compat_getsockopt = compat_ipv6_getsockopt,
1093 * DCCP over IPv4 via INET6 API
1095 static struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1096 .queue_xmit = ip_queue_xmit,
1097 .send_check = dccp_v4_send_check,
1098 .rebuild_header = inet_sk_rebuild_header,
1099 .conn_request = dccp_v6_conn_request,
1100 .syn_recv_sock = dccp_v6_request_recv_sock,
1101 .net_header_len = sizeof(struct iphdr),
1102 .setsockopt = ipv6_setsockopt,
1103 .getsockopt = ipv6_getsockopt,
1104 .addr2sockaddr = inet6_csk_addr2sockaddr,
1105 .sockaddr_len = sizeof(struct sockaddr_in6),
1106 #ifdef CONFIG_COMPAT
1107 .compat_setsockopt = compat_ipv6_setsockopt,
1108 .compat_getsockopt = compat_ipv6_getsockopt,
1112 /* NOTE: A lot of things set to zero explicitly by call to
1113 * sk_alloc() so need not be done here.
1115 static int dccp_v6_init_sock(struct sock *sk)
1117 static __u8 dccp_v6_ctl_sock_initialized;
1118 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1121 if (unlikely(!dccp_v6_ctl_sock_initialized))
1122 dccp_v6_ctl_sock_initialized = 1;
1123 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1129 static int dccp_v6_destroy_sock(struct sock *sk)
1131 dccp_destroy_sock(sk);
1132 return inet6_destroy_sock(sk);
1135 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1136 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1139 static struct proto dccp_v6_prot = {
1141 .owner = THIS_MODULE,
1142 .close = dccp_close,
1143 .connect = dccp_v6_connect,
1144 .disconnect = dccp_disconnect,
1145 .ioctl = dccp_ioctl,
1146 .init = dccp_v6_init_sock,
1147 .setsockopt = dccp_setsockopt,
1148 .getsockopt = dccp_getsockopt,
1149 .sendmsg = dccp_sendmsg,
1150 .recvmsg = dccp_recvmsg,
1151 .backlog_rcv = dccp_v6_do_rcv,
1152 .hash = dccp_v6_hash,
1153 .unhash = dccp_unhash,
1154 .accept = inet_csk_accept,
1155 .get_port = dccp_v6_get_port,
1156 .shutdown = dccp_shutdown,
1157 .destroy = dccp_v6_destroy_sock,
1158 .orphan_count = &dccp_orphan_count,
1159 .max_header = MAX_DCCP_HEADER,
1160 .obj_size = sizeof(struct dccp6_sock),
1161 .rsk_prot = &dccp6_request_sock_ops,
1162 .twsk_prot = &dccp6_timewait_sock_ops,
1163 #ifdef CONFIG_COMPAT
1164 .compat_setsockopt = compat_dccp_setsockopt,
1165 .compat_getsockopt = compat_dccp_getsockopt,
1169 static struct inet6_protocol dccp_v6_protocol = {
1170 .handler = dccp_v6_rcv,
1171 .err_handler = dccp_v6_err,
1172 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1175 static struct proto_ops inet6_dccp_ops = {
1177 .owner = THIS_MODULE,
1178 .release = inet6_release,
1180 .connect = inet_stream_connect,
1181 .socketpair = sock_no_socketpair,
1182 .accept = inet_accept,
1183 .getname = inet6_getname,
1185 .ioctl = inet6_ioctl,
1186 .listen = inet_dccp_listen,
1187 .shutdown = inet_shutdown,
1188 .setsockopt = sock_common_setsockopt,
1189 .getsockopt = sock_common_getsockopt,
1190 .sendmsg = inet_sendmsg,
1191 .recvmsg = sock_common_recvmsg,
1192 .mmap = sock_no_mmap,
1193 .sendpage = sock_no_sendpage,
1194 #ifdef CONFIG_COMPAT
1195 .compat_setsockopt = compat_sock_common_setsockopt,
1196 .compat_getsockopt = compat_sock_common_getsockopt,
1200 static struct inet_protosw dccp_v6_protosw = {
1202 .protocol = IPPROTO_DCCP,
1203 .prot = &dccp_v6_prot,
1204 .ops = &inet6_dccp_ops,
1206 .flags = INET_PROTOSW_ICSK,
1209 static int __init dccp_v6_init(void)
1211 int err = proto_register(&dccp_v6_prot, 1);
1216 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1218 goto out_unregister_proto;
1220 inet6_register_protosw(&dccp_v6_protosw);
1222 err = inet_csk_ctl_sock_create(&dccp_v6_ctl_socket, PF_INET6,
1223 SOCK_DCCP, IPPROTO_DCCP);
1225 goto out_unregister_protosw;
1228 out_unregister_protosw:
1229 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1230 inet6_unregister_protosw(&dccp_v6_protosw);
1231 out_unregister_proto:
1232 proto_unregister(&dccp_v6_prot);
1236 static void __exit dccp_v6_exit(void)
1238 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1239 inet6_unregister_protosw(&dccp_v6_protosw);
1240 proto_unregister(&dccp_v6_prot);
1243 module_init(dccp_v6_init);
1244 module_exit(dccp_v6_exit);
1247 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1248 * values directly, Also cover the case where the protocol is not specified,
1249 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1251 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-33-type-6");
1252 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-0-type-6");
1253 MODULE_LICENSE("GPL");
1254 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1255 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");