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/config.h>
16 #include <linux/module.h>
17 #include <linux/random.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/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>
34 static void dccp_v6_ctl_send_reset(struct sk_buff *skb);
35 static void dccp_v6_reqsk_send_ack(struct sk_buff *skb,
36 struct request_sock *req);
37 static void dccp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb);
39 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
41 static struct inet_connection_sock_af_ops dccp_ipv6_mapped;
42 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
44 static int dccp_v6_get_port(struct sock *sk, unsigned short snum)
46 return inet_csk_get_port(&dccp_hashinfo, sk, snum,
47 inet6_csk_bind_conflict);
50 static void dccp_v6_hash(struct sock *sk)
52 if (sk->sk_state != DCCP_CLOSED) {
53 if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) {
58 __inet6_hash(&dccp_hashinfo, sk);
63 static inline u16 dccp_v6_check(struct dccp_hdr *dh, int len,
64 struct in6_addr *saddr,
65 struct in6_addr *daddr,
68 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_DCCP, base);
71 static __u32 dccp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
73 const struct dccp_hdr *dh = dccp_hdr(skb);
75 if (skb->protocol == htons(ETH_P_IPV6))
76 return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32,
77 skb->nh.ipv6h->saddr.s6_addr32,
81 return secure_dccp_sequence_number(skb->nh.iph->daddr,
87 static int __dccp_v6_check_established(struct sock *sk, const __u16 lport,
88 struct inet_timewait_sock **twp)
90 struct inet_sock *inet = inet_sk(sk);
91 const struct ipv6_pinfo *np = inet6_sk(sk);
92 const struct in6_addr *daddr = &np->rcv_saddr;
93 const struct in6_addr *saddr = &np->daddr;
94 const int dif = sk->sk_bound_dev_if;
95 const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
96 const unsigned int hash = inet6_ehashfn(daddr, inet->num,
98 struct inet_ehash_bucket *head = inet_ehash_bucket(&dccp_hashinfo, hash);
100 const struct hlist_node *node;
101 struct inet_timewait_sock *tw;
103 prefetch(head->chain.first);
104 write_lock(&head->lock);
106 /* Check TIME-WAIT sockets first. */
107 sk_for_each(sk2, node, &(head + dccp_hashinfo.ehash_size)->chain) {
108 const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2);
112 if(*((__u32 *)&(tw->tw_dport)) == ports &&
113 sk2->sk_family == PF_INET6 &&
114 ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
115 ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
116 sk2->sk_bound_dev_if == sk->sk_bound_dev_if)
121 /* And established part... */
122 sk_for_each(sk2, node, &head->chain) {
123 if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif))
127 BUG_TRAP(sk_unhashed(sk));
128 __sk_add_node(sk, &head->chain);
130 sock_prot_inc_use(sk->sk_prot);
131 write_unlock(&head->lock);
135 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
137 /* Silly. Should hash-dance instead... */
138 inet_twsk_deschedule(tw, &dccp_death_row);
139 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
146 write_unlock(&head->lock);
147 return -EADDRNOTAVAIL;
150 static inline u32 dccp_v6_port_offset(const struct sock *sk)
152 const struct inet_sock *inet = inet_sk(sk);
153 const struct ipv6_pinfo *np = inet6_sk(sk);
155 return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32,
160 static int dccp_v6_hash_connect(struct sock *sk)
162 const unsigned short snum = inet_sk(sk)->num;
163 struct inet_bind_hashbucket *head;
164 struct inet_bind_bucket *tb;
168 int low = sysctl_local_port_range[0];
169 int high = sysctl_local_port_range[1];
170 int range = high - low;
174 u32 offset = hint + dccp_v6_port_offset(sk);
175 struct hlist_node *node;
176 struct inet_timewait_sock *tw = NULL;
179 for (i = 1; i <= range; i++) {
180 port = low + (i + offset) % range;
181 head = &dccp_hashinfo.bhash[inet_bhashfn(port,
182 dccp_hashinfo.bhash_size)];
183 spin_lock(&head->lock);
185 /* Does not bother with rcv_saddr checks,
186 * because the established check is already
189 inet_bind_bucket_for_each(tb, node, &head->chain) {
190 if (tb->port == port) {
191 BUG_TRAP(!hlist_empty(&tb->owners));
192 if (tb->fastreuse >= 0)
194 if (!__dccp_v6_check_established(sk,
202 tb = inet_bind_bucket_create(dccp_hashinfo.bind_bucket_cachep,
205 spin_unlock(&head->lock);
212 spin_unlock(&head->lock);
216 return -EADDRNOTAVAIL;
220 /* Head lock still held and bh's disabled */
221 inet_bind_hash(sk, tb, port);
222 if (sk_unhashed(sk)) {
223 inet_sk(sk)->sport = htons(port);
224 __inet6_hash(&dccp_hashinfo, sk);
226 spin_unlock(&head->lock);
229 inet_twsk_deschedule(tw, &dccp_death_row);
237 head = &dccp_hashinfo.bhash[inet_bhashfn(snum,
238 dccp_hashinfo.bhash_size)];
239 tb = inet_csk(sk)->icsk_bind_hash;
240 spin_lock_bh(&head->lock);
242 if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
243 __inet6_hash(&dccp_hashinfo, sk);
244 spin_unlock_bh(&head->lock);
247 spin_unlock(&head->lock);
248 /* No definite answer... Walk to established hash table */
249 ret = __dccp_v6_check_established(sk, snum, NULL);
256 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
259 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
260 struct inet_sock *inet = inet_sk(sk);
261 struct ipv6_pinfo *np = inet6_sk(sk);
262 struct dccp_sock *dp = dccp_sk(sk);
263 struct in6_addr *saddr = NULL, *final_p = NULL, final;
265 struct dst_entry *dst;
269 dp->dccps_role = DCCP_ROLE_CLIENT;
271 if (addr_len < SIN6_LEN_RFC2133)
274 if (usin->sin6_family != AF_INET6)
275 return -EAFNOSUPPORT;
277 memset(&fl, 0, sizeof(fl));
280 fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
281 IP6_ECN_flow_init(fl.fl6_flowlabel);
282 if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) {
283 struct ip6_flowlabel *flowlabel;
284 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
285 if (flowlabel == NULL)
287 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
288 fl6_sock_release(flowlabel);
293 * connect() to INADDR_ANY means loopback (BSD'ism).
296 if (ipv6_addr_any(&usin->sin6_addr))
297 usin->sin6_addr.s6_addr[15] = 0x1;
299 addr_type = ipv6_addr_type(&usin->sin6_addr);
301 if(addr_type & IPV6_ADDR_MULTICAST)
304 if (addr_type & IPV6_ADDR_LINKLOCAL) {
305 if (addr_len >= sizeof(struct sockaddr_in6) &&
306 usin->sin6_scope_id) {
307 /* If interface is set while binding, indices
310 if (sk->sk_bound_dev_if &&
311 sk->sk_bound_dev_if != usin->sin6_scope_id)
314 sk->sk_bound_dev_if = usin->sin6_scope_id;
317 /* Connect to link-local address requires an interface */
318 if (!sk->sk_bound_dev_if)
322 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
323 np->flow_label = fl.fl6_flowlabel;
329 if (addr_type == IPV6_ADDR_MAPPED) {
330 u32 exthdrlen = dp->dccps_ext_header_len;
331 struct sockaddr_in sin;
333 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
335 if (__ipv6_only_sock(sk))
338 sin.sin_family = AF_INET;
339 sin.sin_port = usin->sin6_port;
340 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
342 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_mapped;
343 sk->sk_backlog_rcv = dccp_v4_do_rcv;
345 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
348 dp->dccps_ext_header_len = exthdrlen;
349 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
350 sk->sk_backlog_rcv = dccp_v6_do_rcv;
353 ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
355 ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
362 if (!ipv6_addr_any(&np->rcv_saddr))
363 saddr = &np->rcv_saddr;
365 fl.proto = IPPROTO_DCCP;
366 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
367 ipv6_addr_copy(&fl.fl6_src, saddr ? saddr : &np->saddr);
368 fl.oif = sk->sk_bound_dev_if;
369 fl.fl_ip_dport = usin->sin6_port;
370 fl.fl_ip_sport = inet->sport;
372 if (np->opt && np->opt->srcrt) {
373 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
374 ipv6_addr_copy(&final, &fl.fl6_dst);
375 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
379 err = ip6_dst_lookup(sk, &dst, &fl);
383 ipv6_addr_copy(&fl.fl6_dst, final_p);
385 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
390 ipv6_addr_copy(&np->rcv_saddr, saddr);
393 /* set the source address */
394 ipv6_addr_copy(&np->saddr, saddr);
395 inet->rcv_saddr = LOOPBACK4_IPV6;
397 ip6_dst_store(sk, dst, NULL);
399 dp->dccps_ext_header_len = 0;
401 dp->dccps_ext_header_len = np->opt->opt_flen + np->opt->opt_nflen;
403 inet->dport = usin->sin6_port;
405 dccp_set_state(sk, DCCP_REQUESTING);
406 err = dccp_v6_hash_connect(sk);
411 dp->dccps_gar = secure_dccp_v6_sequence_number(np->saddr.s6_addr32,
416 err = dccp_connect(sk);
423 dccp_set_state(sk, DCCP_CLOSED);
427 sk->sk_route_caps = 0;
431 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
432 int type, int code, int offset, __u32 info)
434 struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data;
435 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
436 struct ipv6_pinfo *np;
441 sk = inet6_lookup(&dccp_hashinfo, &hdr->daddr, dh->dccph_dport,
442 &hdr->saddr, dh->dccph_sport, skb->dev->ifindex);
445 ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
449 if (sk->sk_state == DCCP_TIME_WAIT) {
450 inet_twsk_put((struct inet_timewait_sock *)sk);
455 if (sock_owned_by_user(sk))
456 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
458 if (sk->sk_state == DCCP_CLOSED)
463 if (type == ICMPV6_PKT_TOOBIG) {
464 struct dccp_sock *dp = dccp_sk(sk);
465 struct dst_entry *dst = NULL;
467 if (sock_owned_by_user(sk))
469 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
472 /* icmp should have updated the destination cache entry */
473 dst = __sk_dst_check(sk, np->dst_cookie);
476 struct inet_sock *inet = inet_sk(sk);
479 /* BUGGG_FUTURE: Again, it is not clear how
480 to handle rthdr case. Ignore this complexity
483 memset(&fl, 0, sizeof(fl));
484 fl.proto = IPPROTO_DCCP;
485 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
486 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
487 fl.oif = sk->sk_bound_dev_if;
488 fl.fl_ip_dport = inet->dport;
489 fl.fl_ip_sport = inet->sport;
491 if ((err = ip6_dst_lookup(sk, &dst, &fl))) {
492 sk->sk_err_soft = -err;
496 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
497 sk->sk_err_soft = -err;
504 if (dp->dccps_pmtu_cookie > dst_mtu(dst)) {
505 dccp_sync_mss(sk, dst_mtu(dst));
506 } /* else let the usual retransmit timer handle it */
511 icmpv6_err_convert(type, code, &err);
513 seq = DCCP_SKB_CB(skb)->dccpd_seq;
514 /* Might be for an request_sock */
515 switch (sk->sk_state) {
516 struct request_sock *req, **prev;
518 if (sock_owned_by_user(sk))
521 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
522 &hdr->daddr, &hdr->saddr,
527 /* ICMPs are not backlogged, hence we cannot get
528 * an established socket here.
530 BUG_TRAP(req->sk == NULL);
532 if (seq != dccp_rsk(req)->dreq_iss) {
533 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
537 inet_csk_reqsk_queue_drop(sk, req, prev);
540 case DCCP_REQUESTING:
541 case DCCP_RESPOND: /* Cannot happen.
542 It can, it SYNs are crossed. --ANK */
543 if (!sock_owned_by_user(sk)) {
544 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
547 * Wake people up to see the error
548 * (see connect in sock.c)
550 sk->sk_error_report(sk);
554 sk->sk_err_soft = err;
558 if (!sock_owned_by_user(sk) && np->recverr) {
560 sk->sk_error_report(sk);
562 sk->sk_err_soft = err;
570 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
571 struct dst_entry *dst)
573 struct inet6_request_sock *ireq6 = inet6_rsk(req);
574 struct ipv6_pinfo *np = inet6_sk(sk);
576 struct ipv6_txoptions *opt = NULL;
577 struct in6_addr *final_p = NULL, final;
581 memset(&fl, 0, sizeof(fl));
582 fl.proto = IPPROTO_DCCP;
583 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
584 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
585 fl.fl6_flowlabel = 0;
587 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
588 fl.fl_ip_sport = inet_sk(sk)->sport;
593 np->rxopt.bits.osrcrt == 2 &&
595 struct sk_buff *pktopts = ireq6->pktopts;
596 struct inet6_skb_parm *rxopt = IP6CB(pktopts);
598 opt = ipv6_invert_rthdr(sk,
599 (struct ipv6_rt_hdr *)(pktopts->nh.raw +
603 if (opt && opt->srcrt) {
604 struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
605 ipv6_addr_copy(&final, &fl.fl6_dst);
606 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
610 err = ip6_dst_lookup(sk, &dst, &fl);
614 ipv6_addr_copy(&fl.fl6_dst, final_p);
615 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
619 skb = dccp_make_response(sk, dst, req);
621 struct dccp_hdr *dh = dccp_hdr(skb);
622 dh->dccph_checksum = dccp_v6_check(dh, skb->len,
625 csum_partial((char *)dh,
628 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
629 err = ip6_xmit(sk, skb, &fl, opt, 0);
630 if (err == NET_XMIT_CN)
635 if (opt && opt != np->opt)
636 sock_kfree_s(sk, opt, opt->tot_len);
640 static void dccp_v6_reqsk_destructor(struct request_sock *req)
642 if (inet6_rsk(req)->pktopts != NULL)
643 kfree_skb(inet6_rsk(req)->pktopts);
646 static struct request_sock_ops dccp6_request_sock_ops = {
648 .obj_size = sizeof(struct dccp6_request_sock),
649 .rtx_syn_ack = dccp_v6_send_response,
650 .send_ack = dccp_v6_reqsk_send_ack,
651 .destructor = dccp_v6_reqsk_destructor,
652 .send_reset = dccp_v6_ctl_send_reset,
655 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
656 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
659 static void dccp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb)
661 struct ipv6_pinfo *np = inet6_sk(sk);
662 struct dccp_hdr *dh = dccp_hdr(skb);
664 dh->dccph_checksum = csum_ipv6_magic(&np->saddr, &np->daddr,
666 csum_partial((char *)dh,
671 static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb)
673 struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
674 const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
675 sizeof(struct dccp_hdr_ext) +
676 sizeof(struct dccp_hdr_reset);
681 if (rxdh->dccph_type == DCCP_PKT_RESET)
684 if (!ipv6_unicast_destination(rxskb))
688 * We need to grab some memory, and put together an RST,
689 * and then put it into the queue to be sent.
692 skb = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) +
693 dccp_hdr_reset_len, GFP_ATOMIC);
697 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr) +
700 skb->h.raw = skb_push(skb, dccp_hdr_reset_len);
702 memset(dh, 0, dccp_hdr_reset_len);
704 /* Swap the send and the receive. */
705 dh->dccph_type = DCCP_PKT_RESET;
706 dh->dccph_sport = rxdh->dccph_dport;
707 dh->dccph_dport = rxdh->dccph_sport;
708 dh->dccph_doff = dccp_hdr_reset_len / 4;
710 dccp_hdr_reset(skb)->dccph_reset_code =
711 DCCP_SKB_CB(rxskb)->dccpd_reset_code;
713 /* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */
715 if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
716 dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
718 dccp_hdr_set_seq(dh, seqno);
719 dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
720 DCCP_SKB_CB(rxskb)->dccpd_seq);
722 memset(&fl, 0, sizeof(fl));
723 ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr);
724 ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr);
725 dh->dccph_checksum = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
726 sizeof(*dh), IPPROTO_DCCP,
728 fl.proto = IPPROTO_DCCP;
729 fl.oif = inet6_iif(rxskb);
730 fl.fl_ip_dport = dh->dccph_dport;
731 fl.fl_ip_sport = dh->dccph_sport;
733 /* sk = NULL, but it is safe for now. RST socket required. */
734 if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) {
735 if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) {
736 ip6_xmit(NULL, skb, &fl, NULL, 0);
737 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
738 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
746 static void dccp_v6_ctl_send_ack(struct sk_buff *rxskb)
749 struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
750 const int dccp_hdr_ack_len = sizeof(struct dccp_hdr) +
751 sizeof(struct dccp_hdr_ext) +
752 sizeof(struct dccp_hdr_ack_bits);
755 skb = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) +
756 dccp_hdr_ack_len, GFP_ATOMIC);
760 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr) +
763 skb->h.raw = skb_push(skb, dccp_hdr_ack_len);
765 memset(dh, 0, dccp_hdr_ack_len);
767 /* Build DCCP header and checksum it. */
768 dh->dccph_type = DCCP_PKT_ACK;
769 dh->dccph_sport = rxdh->dccph_dport;
770 dh->dccph_dport = rxdh->dccph_sport;
771 dh->dccph_doff = dccp_hdr_ack_len / 4;
774 dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq);
775 dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
776 DCCP_SKB_CB(rxskb)->dccpd_seq);
778 memset(&fl, 0, sizeof(fl));
779 ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr);
780 ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr);
782 /* FIXME: calculate checksum, IPv4 also should... */
784 fl.proto = IPPROTO_DCCP;
785 fl.oif = inet6_iif(rxskb);
786 fl.fl_ip_dport = dh->dccph_dport;
787 fl.fl_ip_sport = dh->dccph_sport;
789 if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) {
790 if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) {
791 ip6_xmit(NULL, skb, &fl, NULL, 0);
792 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
800 static void dccp_v6_reqsk_send_ack(struct sk_buff *skb,
801 struct request_sock *req)
803 dccp_v6_ctl_send_ack(skb);
806 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
808 const struct dccp_hdr *dh = dccp_hdr(skb);
809 const struct ipv6hdr *iph = skb->nh.ipv6h;
811 struct request_sock **prev;
812 /* Find possible connection requests. */
813 struct request_sock *req = inet6_csk_search_req(sk, &prev,
819 return dccp_check_req(sk, skb, req, prev);
821 nsk = __inet6_lookup_established(&dccp_hashinfo,
822 &iph->saddr, dh->dccph_sport,
823 &iph->daddr, ntohs(dh->dccph_dport),
827 if (nsk->sk_state != DCCP_TIME_WAIT) {
831 inet_twsk_put((struct inet_timewait_sock *)nsk);
838 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
840 struct inet_request_sock *ireq;
842 struct request_sock *req;
843 struct dccp_request_sock *dreq;
844 struct inet6_request_sock *ireq6;
845 struct ipv6_pinfo *np = inet6_sk(sk);
846 const __u32 service = dccp_hdr_request(skb)->dccph_req_service;
847 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
848 __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
850 if (skb->protocol == htons(ETH_P_IP))
851 return dccp_v4_conn_request(sk, skb);
853 if (!ipv6_unicast_destination(skb))
856 if (dccp_bad_service_code(sk, service)) {
857 reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
861 * There are no SYN attacks on IPv6, yet...
863 if (inet_csk_reqsk_queue_is_full(sk))
866 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
869 req = inet6_reqsk_alloc(sk->sk_prot->rsk_prot);
873 /* FIXME: process options */
875 dccp_openreq_init(req, &dp, skb);
877 ireq6 = inet6_rsk(req);
878 ireq = inet_rsk(req);
879 ipv6_addr_copy(&ireq6->rmt_addr, &skb->nh.ipv6h->saddr);
880 ipv6_addr_copy(&ireq6->loc_addr, &skb->nh.ipv6h->daddr);
881 req->rcv_wnd = 100; /* Fake, option parsing will get the
883 ireq6->pktopts = NULL;
885 if (ipv6_opt_accepted(sk, skb) ||
886 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
887 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
888 atomic_inc(&skb->users);
889 ireq6->pktopts = skb;
891 ireq6->iif = sk->sk_bound_dev_if;
893 /* So that link locals have meaning */
894 if (!sk->sk_bound_dev_if &&
895 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
896 ireq6->iif = inet6_iif(skb);
899 * Step 3: Process LISTEN state
901 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
903 * In fact we defer setting S.GSR, S.SWL, S.SWH to
904 * dccp_create_openreq_child.
906 dreq = dccp_rsk(req);
907 dreq->dreq_isr = dcb->dccpd_seq;
908 dreq->dreq_iss = dccp_v6_init_sequence(sk, skb);
909 dreq->dreq_service = service;
911 if (dccp_v6_send_response(sk, req, NULL))
914 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
920 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
921 dcb->dccpd_reset_code = reset_code;
925 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
927 struct request_sock *req,
928 struct dst_entry *dst)
930 struct inet6_request_sock *ireq6 = inet6_rsk(req);
931 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
932 struct inet_sock *newinet;
933 struct dccp_sock *newdp;
934 struct dccp6_sock *newdp6;
936 struct ipv6_txoptions *opt;
938 if (skb->protocol == htons(ETH_P_IP)) {
943 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
947 newdp6 = (struct dccp6_sock *)newsk;
948 newdp = dccp_sk(newsk);
949 newinet = inet_sk(newsk);
950 newinet->pinet6 = &newdp6->inet6;
951 newnp = inet6_sk(newsk);
953 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
955 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
958 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
961 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
963 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
964 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
965 newnp->pktoptions = NULL;
967 newnp->mcast_oif = inet6_iif(skb);
968 newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
971 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
972 * here, dccp_create_openreq_child now does this for us, see the comment in
973 * that function for the gory details. -acme
976 /* It is tricky place. Until this moment IPv4 tcp
977 worked with IPv6 icsk.icsk_af_ops.
980 dccp_sync_mss(newsk, newdp->dccps_pmtu_cookie);
987 if (sk_acceptq_is_full(sk))
990 if (np->rxopt.bits.osrcrt == 2 &&
991 opt == NULL && ireq6->pktopts) {
992 struct inet6_skb_parm *rxopt = IP6CB(ireq6->pktopts);
994 opt = ipv6_invert_rthdr(sk,
995 (struct ipv6_rt_hdr *)(ireq6->pktopts->nh.raw +
1000 struct in6_addr *final_p = NULL, final;
1003 memset(&fl, 0, sizeof(fl));
1004 fl.proto = IPPROTO_DCCP;
1005 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
1006 if (opt && opt->srcrt) {
1007 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
1008 ipv6_addr_copy(&final, &fl.fl6_dst);
1009 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1012 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
1013 fl.oif = sk->sk_bound_dev_if;
1014 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
1015 fl.fl_ip_sport = inet_sk(sk)->sport;
1017 if (ip6_dst_lookup(sk, &dst, &fl))
1021 ipv6_addr_copy(&fl.fl6_dst, final_p);
1023 if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
1027 newsk = dccp_create_openreq_child(sk, req, skb);
1032 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1033 * count here, dccp_create_openreq_child now does this for us, see the
1034 * comment in that function for the gory details. -acme
1037 ip6_dst_store(newsk, dst, NULL);
1038 newsk->sk_route_caps = dst->dev->features &
1039 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1041 newdp6 = (struct dccp6_sock *)newsk;
1042 newinet = inet_sk(newsk);
1043 newinet->pinet6 = &newdp6->inet6;
1044 newdp = dccp_sk(newsk);
1045 newnp = inet6_sk(newsk);
1047 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1049 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
1050 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
1051 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
1052 newsk->sk_bound_dev_if = ireq6->iif;
1054 /* Now IPv6 options...
1056 First: no IPv4 options.
1058 newinet->opt = NULL;
1061 newnp->rxopt.all = np->rxopt.all;
1063 /* Clone pktoptions received with SYN */
1064 newnp->pktoptions = NULL;
1065 if (ireq6->pktopts != NULL) {
1066 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
1067 kfree_skb(ireq6->pktopts);
1068 ireq6->pktopts = NULL;
1069 if (newnp->pktoptions)
1070 skb_set_owner_r(newnp->pktoptions, newsk);
1073 newnp->mcast_oif = inet6_iif(skb);
1074 newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
1076 /* Clone native IPv6 options from listening socket (if any)
1078 Yes, keeping reference count would be much more clever,
1079 but we make one more one thing there: reattach optmem
1083 newnp->opt = ipv6_dup_options(newsk, opt);
1085 sock_kfree_s(sk, opt, opt->tot_len);
1088 newdp->dccps_ext_header_len = 0;
1090 newdp->dccps_ext_header_len = newnp->opt->opt_nflen +
1091 newnp->opt->opt_flen;
1093 dccp_sync_mss(newsk, dst_mtu(dst));
1095 newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
1097 __inet6_hash(&dccp_hashinfo, newsk);
1098 inet_inherit_port(&dccp_hashinfo, sk, newsk);
1103 NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
1105 NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
1106 if (opt && opt != np->opt)
1107 sock_kfree_s(sk, opt, opt->tot_len);
1112 /* The socket must have it's spinlock held when we get
1115 * We have a potential double-lock case here, so even when
1116 * doing backlog processing we use the BH locking scheme.
1117 * This is because we cannot sleep with the original spinlock
1120 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
1122 struct ipv6_pinfo *np = inet6_sk(sk);
1123 struct sk_buff *opt_skb = NULL;
1125 /* Imagine: socket is IPv6. IPv4 packet arrives,
1126 goes to IPv4 receive handler and backlogged.
1127 From backlog it always goes here. Kerboom...
1128 Fortunately, dccp_rcv_established and rcv_established
1129 handle them correctly, but it is not case with
1130 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
1133 if (skb->protocol == htons(ETH_P_IP))
1134 return dccp_v4_do_rcv(sk, skb);
1136 if (sk_filter(sk, skb, 0))
1140 * socket locking is here for SMP purposes as backlog rcv
1141 * is currently called with bh processing disabled.
1144 /* Do Stevens' IPV6_PKTOPTIONS.
1146 Yes, guys, it is the only place in our code, where we
1147 may make it not affecting IPv4.
1148 The rest of code is protocol independent,
1149 and I do not like idea to uglify IPv4.
1151 Actually, all the idea behind IPV6_PKTOPTIONS
1152 looks not very well thought. For now we latch
1153 options, received in the last packet, enqueued
1154 by tcp. Feel free to propose better solution.
1158 opt_skb = skb_clone(skb, GFP_ATOMIC);
1160 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
1161 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
1166 if (sk->sk_state == DCCP_LISTEN) {
1167 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
1172 * Queue it on the new socket if the new socket is active,
1173 * otherwise we just shortcircuit this and continue with
1177 if (dccp_child_process(sk, nsk, skb))
1180 __kfree_skb(opt_skb);
1185 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
1190 dccp_v6_ctl_send_reset(skb);
1193 __kfree_skb(opt_skb);
1198 static int dccp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
1200 const struct dccp_hdr *dh;
1201 struct sk_buff *skb = *pskb;
1205 /* Step 1: Check header basics: */
1207 if (dccp_invalid_packet(skb))
1212 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
1213 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
1215 if (dccp_packet_without_ack(skb))
1216 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
1218 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
1221 * Look up flow ID in table and get corresponding socket */
1222 sk = __inet6_lookup(&dccp_hashinfo, &skb->nh.ipv6h->saddr,
1224 &skb->nh.ipv6h->daddr, ntohs(dh->dccph_dport),
1229 * Generate Reset(No Connection) unless P.type == Reset
1230 * Drop packet and return
1233 goto no_dccp_socket;
1237 * ... or S.state == TIMEWAIT,
1238 * Generate Reset(No Connection) unless P.type == Reset
1239 * Drop packet and return
1242 if (sk->sk_state == DCCP_TIME_WAIT)
1245 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
1246 goto discard_and_relse;
1248 if (sk_filter(sk, skb, 0))
1249 goto discard_and_relse;
1255 if (!sock_owned_by_user(sk))
1256 rc = dccp_v6_do_rcv(sk, skb);
1258 sk_add_backlog(sk, skb);
1265 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1269 * Generate Reset(No Connection) unless P.type == Reset
1270 * Drop packet and return
1272 if (dh->dccph_type != DCCP_PKT_RESET) {
1273 DCCP_SKB_CB(skb)->dccpd_reset_code =
1274 DCCP_RESET_CODE_NO_CONNECTION;
1275 dccp_v6_ctl_send_reset(skb);
1291 inet_twsk_put((struct inet_timewait_sock *)sk);
1292 goto no_dccp_socket;
1295 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1296 .queue_xmit = inet6_csk_xmit,
1297 .send_check = dccp_v6_send_check,
1298 .rebuild_header = inet6_sk_rebuild_header,
1299 .conn_request = dccp_v6_conn_request,
1300 .syn_recv_sock = dccp_v6_request_recv_sock,
1301 .net_header_len = sizeof(struct ipv6hdr),
1302 .setsockopt = ipv6_setsockopt,
1303 .getsockopt = ipv6_getsockopt,
1304 .addr2sockaddr = inet6_csk_addr2sockaddr,
1305 .sockaddr_len = sizeof(struct sockaddr_in6)
1309 * DCCP over IPv4 via INET6 API
1311 static struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1312 .queue_xmit = ip_queue_xmit,
1313 .send_check = dccp_v4_send_check,
1314 .rebuild_header = inet_sk_rebuild_header,
1315 .conn_request = dccp_v6_conn_request,
1316 .syn_recv_sock = dccp_v6_request_recv_sock,
1317 .net_header_len = sizeof(struct iphdr),
1318 .setsockopt = ipv6_setsockopt,
1319 .getsockopt = ipv6_getsockopt,
1320 .addr2sockaddr = inet6_csk_addr2sockaddr,
1321 .sockaddr_len = sizeof(struct sockaddr_in6)
1324 /* NOTE: A lot of things set to zero explicitly by call to
1325 * sk_alloc() so need not be done here.
1327 static int dccp_v6_init_sock(struct sock *sk)
1329 int err = dccp_v4_init_sock(sk);
1332 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1337 static int dccp_v6_destroy_sock(struct sock *sk)
1339 dccp_v4_destroy_sock(sk);
1340 return inet6_destroy_sock(sk);
1343 static struct proto dccp_v6_prot = {
1345 .owner = THIS_MODULE,
1346 .close = dccp_close,
1347 .connect = dccp_v6_connect,
1348 .disconnect = dccp_disconnect,
1349 .ioctl = dccp_ioctl,
1350 .init = dccp_v6_init_sock,
1351 .setsockopt = dccp_setsockopt,
1352 .getsockopt = dccp_getsockopt,
1353 .sendmsg = dccp_sendmsg,
1354 .recvmsg = dccp_recvmsg,
1355 .backlog_rcv = dccp_v6_do_rcv,
1356 .hash = dccp_v6_hash,
1357 .unhash = dccp_unhash,
1358 .accept = inet_csk_accept,
1359 .get_port = dccp_v6_get_port,
1360 .shutdown = dccp_shutdown,
1361 .destroy = dccp_v6_destroy_sock,
1362 .orphan_count = &dccp_orphan_count,
1363 .max_header = MAX_DCCP_HEADER,
1364 .obj_size = sizeof(struct dccp6_sock),
1365 .rsk_prot = &dccp6_request_sock_ops,
1366 .twsk_prot = &dccp6_timewait_sock_ops,
1369 static struct inet6_protocol dccp_v6_protocol = {
1370 .handler = dccp_v6_rcv,
1371 .err_handler = dccp_v6_err,
1372 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1375 static struct proto_ops inet6_dccp_ops = {
1377 .owner = THIS_MODULE,
1378 .release = inet6_release,
1380 .connect = inet_stream_connect,
1381 .socketpair = sock_no_socketpair,
1382 .accept = inet_accept,
1383 .getname = inet6_getname,
1385 .ioctl = inet6_ioctl,
1386 .listen = inet_dccp_listen,
1387 .shutdown = inet_shutdown,
1388 .setsockopt = sock_common_setsockopt,
1389 .getsockopt = sock_common_getsockopt,
1390 .sendmsg = inet_sendmsg,
1391 .recvmsg = sock_common_recvmsg,
1392 .mmap = sock_no_mmap,
1393 .sendpage = sock_no_sendpage,
1396 static struct inet_protosw dccp_v6_protosw = {
1398 .protocol = IPPROTO_DCCP,
1399 .prot = &dccp_v6_prot,
1400 .ops = &inet6_dccp_ops,
1404 static int __init dccp_v6_init(void)
1406 int err = proto_register(&dccp_v6_prot, 1);
1411 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1413 goto out_unregister_proto;
1415 inet6_register_protosw(&dccp_v6_protosw);
1418 out_unregister_proto:
1419 proto_unregister(&dccp_v6_prot);
1423 static void __exit dccp_v6_exit(void)
1425 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1426 inet6_unregister_protosw(&dccp_v6_protosw);
1427 proto_unregister(&dccp_v6_prot);
1430 module_init(dccp_v6_init);
1431 module_exit(dccp_v6_exit);
1434 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1435 * values directly, Also cover the case where the protocol is not specified,
1436 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1438 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-33-type-6");
1439 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-0-type-6");
1440 MODULE_LICENSE("GPL");
1441 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1442 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");