1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * Linux INET6 implementation
7 * Pedro Roque <roque@di.fc.ul.pt>
10 * linux/net/ipv4/tcp.c
11 * linux/net/ipv4/tcp_input.c
12 * linux/net/ipv4/tcp_output.c
15 * Hideaki YOSHIFUJI : sin6_scope_id support
16 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
17 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
18 * a single port at the same time.
19 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file.
22 #include <linux/bottom_half.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/jiffies.h>
31 #include <linux/in6.h>
32 #include <linux/netdevice.h>
33 #include <linux/init.h>
34 #include <linux/jhash.h>
35 #include <linux/ipsec.h>
36 #include <linux/times.h>
37 #include <linux/slab.h>
38 #include <linux/uaccess.h>
39 #include <linux/ipv6.h>
40 #include <linux/icmpv6.h>
41 #include <linux/random.h>
42 #include <linux/indirect_call_wrapper.h>
45 #include <net/ndisc.h>
46 #include <net/inet6_hashtables.h>
47 #include <net/inet6_connection_sock.h>
49 #include <net/transp_v6.h>
50 #include <net/addrconf.h>
51 #include <net/ip6_route.h>
52 #include <net/ip6_checksum.h>
53 #include <net/inet_ecn.h>
54 #include <net/protocol.h>
57 #include <net/dsfield.h>
58 #include <net/timewait_sock.h>
59 #include <net/inet_common.h>
60 #include <net/secure_seq.h>
61 #include <net/busy_poll.h>
63 #include <linux/proc_fs.h>
64 #include <linux/seq_file.h>
66 #include <crypto/hash.h>
67 #include <linux/scatterlist.h>
69 #include <trace/events/tcp.h>
71 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb);
72 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
73 struct request_sock *req);
75 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
77 static const struct inet_connection_sock_af_ops ipv6_mapped;
78 const struct inet_connection_sock_af_ops ipv6_specific;
79 #ifdef CONFIG_TCP_MD5SIG
80 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific;
81 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific;
83 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk,
84 const struct in6_addr *addr,
91 /* Helper returning the inet6 address from a given tcp socket.
92 * It can be used in TCP stack instead of inet6_sk(sk).
93 * This avoids a dereference and allow compiler optimizations.
94 * It is a specialized version of inet6_sk_generic().
96 static struct ipv6_pinfo *tcp_inet6_sk(const struct sock *sk)
98 unsigned int offset = sizeof(struct tcp6_sock) - sizeof(struct ipv6_pinfo);
100 return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
103 static void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
105 struct dst_entry *dst = skb_dst(skb);
107 if (dst && dst_hold_safe(dst)) {
108 const struct rt6_info *rt = (const struct rt6_info *)dst;
111 inet_sk(sk)->rx_dst_ifindex = skb->skb_iif;
112 tcp_inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
116 static u32 tcp_v6_init_seq(const struct sk_buff *skb)
118 return secure_tcpv6_seq(ipv6_hdr(skb)->daddr.s6_addr32,
119 ipv6_hdr(skb)->saddr.s6_addr32,
121 tcp_hdr(skb)->source);
124 static u32 tcp_v6_init_ts_off(const struct net *net, const struct sk_buff *skb)
126 return secure_tcpv6_ts_off(net, ipv6_hdr(skb)->daddr.s6_addr32,
127 ipv6_hdr(skb)->saddr.s6_addr32);
130 static int tcp_v6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
133 /* This check is replicated from tcp_v6_connect() and intended to
134 * prevent BPF program called below from accessing bytes that are out
135 * of the bound specified by user in addr_len.
137 if (addr_len < SIN6_LEN_RFC2133)
140 sock_owned_by_me(sk);
142 return BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr);
145 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
148 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
149 struct inet_sock *inet = inet_sk(sk);
150 struct inet_connection_sock *icsk = inet_csk(sk);
151 struct ipv6_pinfo *np = tcp_inet6_sk(sk);
152 struct tcp_sock *tp = tcp_sk(sk);
153 struct in6_addr *saddr = NULL, *final_p, final;
154 struct ipv6_txoptions *opt;
156 struct dst_entry *dst;
159 struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
161 if (addr_len < SIN6_LEN_RFC2133)
164 if (usin->sin6_family != AF_INET6)
165 return -EAFNOSUPPORT;
167 memset(&fl6, 0, sizeof(fl6));
170 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
171 IP6_ECN_flow_init(fl6.flowlabel);
172 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
173 struct ip6_flowlabel *flowlabel;
174 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
175 if (IS_ERR(flowlabel))
177 fl6_sock_release(flowlabel);
182 * connect() to INADDR_ANY means loopback (BSD'ism).
185 if (ipv6_addr_any(&usin->sin6_addr)) {
186 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
187 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
190 usin->sin6_addr = in6addr_loopback;
193 addr_type = ipv6_addr_type(&usin->sin6_addr);
195 if (addr_type & IPV6_ADDR_MULTICAST)
198 if (addr_type&IPV6_ADDR_LINKLOCAL) {
199 if (addr_len >= sizeof(struct sockaddr_in6) &&
200 usin->sin6_scope_id) {
201 /* If interface is set while binding, indices
204 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id))
207 sk->sk_bound_dev_if = usin->sin6_scope_id;
210 /* Connect to link-local address requires an interface */
211 if (!sk->sk_bound_dev_if)
215 if (tp->rx_opt.ts_recent_stamp &&
216 !ipv6_addr_equal(&sk->sk_v6_daddr, &usin->sin6_addr)) {
217 tp->rx_opt.ts_recent = 0;
218 tp->rx_opt.ts_recent_stamp = 0;
219 WRITE_ONCE(tp->write_seq, 0);
222 sk->sk_v6_daddr = usin->sin6_addr;
223 np->flow_label = fl6.flowlabel;
229 if (addr_type & IPV6_ADDR_MAPPED) {
230 u32 exthdrlen = icsk->icsk_ext_hdr_len;
231 struct sockaddr_in sin;
233 if (__ipv6_only_sock(sk))
236 sin.sin_family = AF_INET;
237 sin.sin_port = usin->sin6_port;
238 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
240 icsk->icsk_af_ops = &ipv6_mapped;
242 mptcpv6_handle_mapped(sk, true);
243 sk->sk_backlog_rcv = tcp_v4_do_rcv;
244 #ifdef CONFIG_TCP_MD5SIG
245 tp->af_specific = &tcp_sock_ipv6_mapped_specific;
248 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
251 icsk->icsk_ext_hdr_len = exthdrlen;
252 icsk->icsk_af_ops = &ipv6_specific;
254 mptcpv6_handle_mapped(sk, false);
255 sk->sk_backlog_rcv = tcp_v6_do_rcv;
256 #ifdef CONFIG_TCP_MD5SIG
257 tp->af_specific = &tcp_sock_ipv6_specific;
261 np->saddr = sk->sk_v6_rcv_saddr;
266 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr))
267 saddr = &sk->sk_v6_rcv_saddr;
269 fl6.flowi6_proto = IPPROTO_TCP;
270 fl6.daddr = sk->sk_v6_daddr;
271 fl6.saddr = saddr ? *saddr : np->saddr;
272 fl6.flowi6_oif = sk->sk_bound_dev_if;
273 fl6.flowi6_mark = sk->sk_mark;
274 fl6.fl6_dport = usin->sin6_port;
275 fl6.fl6_sport = inet->inet_sport;
276 fl6.flowi6_uid = sk->sk_uid;
278 opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
279 final_p = fl6_update_dst(&fl6, opt, &final);
281 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
283 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
291 sk->sk_v6_rcv_saddr = *saddr;
294 /* set the source address */
296 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
298 sk->sk_gso_type = SKB_GSO_TCPV6;
299 ip6_dst_store(sk, dst, NULL, NULL);
301 icsk->icsk_ext_hdr_len = 0;
303 icsk->icsk_ext_hdr_len = opt->opt_flen +
306 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
308 inet->inet_dport = usin->sin6_port;
310 tcp_set_state(sk, TCP_SYN_SENT);
311 err = inet6_hash_connect(tcp_death_row, sk);
317 if (likely(!tp->repair)) {
319 WRITE_ONCE(tp->write_seq,
320 secure_tcpv6_seq(np->saddr.s6_addr32,
321 sk->sk_v6_daddr.s6_addr32,
324 tp->tsoffset = secure_tcpv6_ts_off(sock_net(sk),
326 sk->sk_v6_daddr.s6_addr32);
329 if (tcp_fastopen_defer_connect(sk, &err))
334 err = tcp_connect(sk);
341 tcp_set_state(sk, TCP_CLOSE);
343 inet->inet_dport = 0;
344 sk->sk_route_caps = 0;
348 static void tcp_v6_mtu_reduced(struct sock *sk)
350 struct dst_entry *dst;
352 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
355 dst = inet6_csk_update_pmtu(sk, tcp_sk(sk)->mtu_info);
359 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
360 tcp_sync_mss(sk, dst_mtu(dst));
361 tcp_simple_retransmit(sk);
365 static int tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
366 u8 type, u8 code, int offset, __be32 info)
368 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
369 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
370 struct net *net = dev_net(skb->dev);
371 struct request_sock *fastopen;
372 struct ipv6_pinfo *np;
379 sk = __inet6_lookup_established(net, &tcp_hashinfo,
380 &hdr->daddr, th->dest,
381 &hdr->saddr, ntohs(th->source),
382 skb->dev->ifindex, inet6_sdif(skb));
385 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
390 if (sk->sk_state == TCP_TIME_WAIT) {
391 inet_twsk_put(inet_twsk(sk));
394 seq = ntohl(th->seq);
395 fatal = icmpv6_err_convert(type, code, &err);
396 if (sk->sk_state == TCP_NEW_SYN_RECV) {
397 tcp_req_err(sk, seq, fatal);
402 if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG)
403 __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
405 if (sk->sk_state == TCP_CLOSE)
408 if (ipv6_hdr(skb)->hop_limit < tcp_inet6_sk(sk)->min_hopcount) {
409 __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP);
414 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
415 fastopen = rcu_dereference(tp->fastopen_rsk);
416 snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;
417 if (sk->sk_state != TCP_LISTEN &&
418 !between(seq, snd_una, tp->snd_nxt)) {
419 __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
423 np = tcp_inet6_sk(sk);
425 if (type == NDISC_REDIRECT) {
426 if (!sock_owned_by_user(sk)) {
427 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
430 dst->ops->redirect(dst, sk, skb);
435 if (type == ICMPV6_PKT_TOOBIG) {
436 /* We are not interested in TCP_LISTEN and open_requests
437 * (SYN-ACKs send out by Linux are always <576bytes so
438 * they should go through unfragmented).
440 if (sk->sk_state == TCP_LISTEN)
443 if (!ip6_sk_accept_pmtu(sk))
446 tp->mtu_info = ntohl(info);
447 if (!sock_owned_by_user(sk))
448 tcp_v6_mtu_reduced(sk);
449 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED,
456 /* Might be for an request_sock */
457 switch (sk->sk_state) {
460 /* Only in fast or simultaneous open. If a fast open socket is
461 * already accepted it is treated as a connected one below.
463 if (fastopen && !fastopen->sk)
466 ipv6_icmp_error(sk, skb, err, th->dest, ntohl(info), (u8 *)th);
468 if (!sock_owned_by_user(sk)) {
470 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */
474 sk->sk_err_soft = err;
479 /* check if this ICMP message allows revert of backoff.
482 if (!fastopen && type == ICMPV6_DEST_UNREACH &&
483 code == ICMPV6_NOROUTE)
484 tcp_ld_RTO_revert(sk, seq);
487 if (!sock_owned_by_user(sk) && np->recverr) {
489 sk->sk_error_report(sk);
491 sk->sk_err_soft = err;
500 static int tcp_v6_send_synack(const struct sock *sk, struct dst_entry *dst,
502 struct request_sock *req,
503 struct tcp_fastopen_cookie *foc,
504 enum tcp_synack_type synack_type,
505 struct sk_buff *syn_skb)
507 struct inet_request_sock *ireq = inet_rsk(req);
508 struct ipv6_pinfo *np = tcp_inet6_sk(sk);
509 struct ipv6_txoptions *opt;
510 struct flowi6 *fl6 = &fl->u.ip6;
515 /* First, grab a route. */
516 if (!dst && (dst = inet6_csk_route_req(sk, fl6, req,
517 IPPROTO_TCP)) == NULL)
520 skb = tcp_make_synack(sk, dst, req, foc, synack_type, syn_skb);
523 __tcp_v6_send_check(skb, &ireq->ir_v6_loc_addr,
524 &ireq->ir_v6_rmt_addr);
526 fl6->daddr = ireq->ir_v6_rmt_addr;
527 if (np->repflow && ireq->pktopts)
528 fl6->flowlabel = ip6_flowlabel(ipv6_hdr(ireq->pktopts));
530 tclass = sock_net(sk)->ipv4.sysctl_tcp_reflect_tos ?
531 (tcp_rsk(req)->syn_tos & ~INET_ECN_MASK) |
532 (np->tclass & INET_ECN_MASK) :
535 if (!INET_ECN_is_capable(tclass) &&
536 tcp_bpf_ca_needs_ecn((struct sock *)req))
537 tclass |= INET_ECN_ECT_0;
540 opt = ireq->ipv6_opt;
542 opt = rcu_dereference(np->opt);
543 err = ip6_xmit(sk, skb, fl6, sk->sk_mark, opt,
544 tclass, sk->sk_priority);
546 err = net_xmit_eval(err);
554 static void tcp_v6_reqsk_destructor(struct request_sock *req)
556 kfree(inet_rsk(req)->ipv6_opt);
557 kfree_skb(inet_rsk(req)->pktopts);
560 #ifdef CONFIG_TCP_MD5SIG
561 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk,
562 const struct in6_addr *addr,
565 return tcp_md5_do_lookup(sk, l3index,
566 (union tcp_md5_addr *)addr, AF_INET6);
569 static struct tcp_md5sig_key *tcp_v6_md5_lookup(const struct sock *sk,
570 const struct sock *addr_sk)
574 l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
575 addr_sk->sk_bound_dev_if);
576 return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr,
580 static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
581 sockptr_t optval, int optlen)
583 struct tcp_md5sig cmd;
584 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr;
588 if (optlen < sizeof(cmd))
591 if (copy_from_sockptr(&cmd, optval, sizeof(cmd)))
594 if (sin6->sin6_family != AF_INET6)
597 if (optname == TCP_MD5SIG_EXT &&
598 cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) {
599 prefixlen = cmd.tcpm_prefixlen;
600 if (prefixlen > 128 || (ipv6_addr_v4mapped(&sin6->sin6_addr) &&
604 prefixlen = ipv6_addr_v4mapped(&sin6->sin6_addr) ? 32 : 128;
607 if (optname == TCP_MD5SIG_EXT &&
608 cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX) {
609 struct net_device *dev;
612 dev = dev_get_by_index_rcu(sock_net(sk), cmd.tcpm_ifindex);
613 if (dev && netif_is_l3_master(dev))
614 l3index = dev->ifindex;
617 /* ok to reference set/not set outside of rcu;
618 * right now device MUST be an L3 master
620 if (!dev || !l3index)
624 if (!cmd.tcpm_keylen) {
625 if (ipv6_addr_v4mapped(&sin6->sin6_addr))
626 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3],
629 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr,
630 AF_INET6, prefixlen, l3index);
633 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
636 if (ipv6_addr_v4mapped(&sin6->sin6_addr))
637 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3],
638 AF_INET, prefixlen, l3index,
639 cmd.tcpm_key, cmd.tcpm_keylen,
642 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr,
643 AF_INET6, prefixlen, l3index,
644 cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
647 static int tcp_v6_md5_hash_headers(struct tcp_md5sig_pool *hp,
648 const struct in6_addr *daddr,
649 const struct in6_addr *saddr,
650 const struct tcphdr *th, int nbytes)
652 struct tcp6_pseudohdr *bp;
653 struct scatterlist sg;
657 /* 1. TCP pseudo-header (RFC2460) */
660 bp->protocol = cpu_to_be32(IPPROTO_TCP);
661 bp->len = cpu_to_be32(nbytes);
663 _th = (struct tcphdr *)(bp + 1);
664 memcpy(_th, th, sizeof(*th));
667 sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th));
668 ahash_request_set_crypt(hp->md5_req, &sg, NULL,
669 sizeof(*bp) + sizeof(*th));
670 return crypto_ahash_update(hp->md5_req);
673 static int tcp_v6_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key,
674 const struct in6_addr *daddr, struct in6_addr *saddr,
675 const struct tcphdr *th)
677 struct tcp_md5sig_pool *hp;
678 struct ahash_request *req;
680 hp = tcp_get_md5sig_pool();
682 goto clear_hash_noput;
685 if (crypto_ahash_init(req))
687 if (tcp_v6_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2))
689 if (tcp_md5_hash_key(hp, key))
691 ahash_request_set_crypt(req, NULL, md5_hash, 0);
692 if (crypto_ahash_final(req))
695 tcp_put_md5sig_pool();
699 tcp_put_md5sig_pool();
701 memset(md5_hash, 0, 16);
705 static int tcp_v6_md5_hash_skb(char *md5_hash,
706 const struct tcp_md5sig_key *key,
707 const struct sock *sk,
708 const struct sk_buff *skb)
710 const struct in6_addr *saddr, *daddr;
711 struct tcp_md5sig_pool *hp;
712 struct ahash_request *req;
713 const struct tcphdr *th = tcp_hdr(skb);
715 if (sk) { /* valid for establish/request sockets */
716 saddr = &sk->sk_v6_rcv_saddr;
717 daddr = &sk->sk_v6_daddr;
719 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
720 saddr = &ip6h->saddr;
721 daddr = &ip6h->daddr;
724 hp = tcp_get_md5sig_pool();
726 goto clear_hash_noput;
729 if (crypto_ahash_init(req))
732 if (tcp_v6_md5_hash_headers(hp, daddr, saddr, th, skb->len))
734 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
736 if (tcp_md5_hash_key(hp, key))
738 ahash_request_set_crypt(req, NULL, md5_hash, 0);
739 if (crypto_ahash_final(req))
742 tcp_put_md5sig_pool();
746 tcp_put_md5sig_pool();
748 memset(md5_hash, 0, 16);
754 static bool tcp_v6_inbound_md5_hash(const struct sock *sk,
755 const struct sk_buff *skb,
758 #ifdef CONFIG_TCP_MD5SIG
759 const __u8 *hash_location = NULL;
760 struct tcp_md5sig_key *hash_expected;
761 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
762 const struct tcphdr *th = tcp_hdr(skb);
763 int genhash, l3index;
766 /* sdif set, means packet ingressed via a device
767 * in an L3 domain and dif is set to the l3mdev
769 l3index = sdif ? dif : 0;
771 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr, l3index);
772 hash_location = tcp_parse_md5sig_option(th);
774 /* We've parsed the options - do we have a hash? */
775 if (!hash_expected && !hash_location)
778 if (hash_expected && !hash_location) {
779 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
783 if (!hash_expected && hash_location) {
784 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
788 /* check the signature */
789 genhash = tcp_v6_md5_hash_skb(newhash,
793 if (genhash || memcmp(hash_location, newhash, 16) != 0) {
794 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE);
795 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u L3 index %d\n",
796 genhash ? "failed" : "mismatch",
797 &ip6h->saddr, ntohs(th->source),
798 &ip6h->daddr, ntohs(th->dest), l3index);
805 static void tcp_v6_init_req(struct request_sock *req,
806 const struct sock *sk_listener,
809 bool l3_slave = ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags);
810 struct inet_request_sock *ireq = inet_rsk(req);
811 const struct ipv6_pinfo *np = tcp_inet6_sk(sk_listener);
813 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
814 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
816 /* So that link locals have meaning */
817 if ((!sk_listener->sk_bound_dev_if || l3_slave) &&
818 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
819 ireq->ir_iif = tcp_v6_iif(skb);
821 if (!TCP_SKB_CB(skb)->tcp_tw_isn &&
822 (ipv6_opt_accepted(sk_listener, skb, &TCP_SKB_CB(skb)->header.h6) ||
823 np->rxopt.bits.rxinfo ||
824 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim ||
825 np->rxopt.bits.rxohlim || np->repflow)) {
826 refcount_inc(&skb->users);
831 static struct dst_entry *tcp_v6_route_req(const struct sock *sk,
834 struct request_sock *req)
836 tcp_v6_init_req(req, sk, skb);
838 if (security_inet_conn_request(sk, skb, req))
841 return inet6_csk_route_req(sk, &fl->u.ip6, req, IPPROTO_TCP);
844 struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
846 .obj_size = sizeof(struct tcp6_request_sock),
847 .rtx_syn_ack = tcp_rtx_synack,
848 .send_ack = tcp_v6_reqsk_send_ack,
849 .destructor = tcp_v6_reqsk_destructor,
850 .send_reset = tcp_v6_send_reset,
851 .syn_ack_timeout = tcp_syn_ack_timeout,
854 const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
855 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
856 sizeof(struct ipv6hdr),
857 #ifdef CONFIG_TCP_MD5SIG
858 .req_md5_lookup = tcp_v6_md5_lookup,
859 .calc_md5_hash = tcp_v6_md5_hash_skb,
861 #ifdef CONFIG_SYN_COOKIES
862 .cookie_init_seq = cookie_v6_init_sequence,
864 .route_req = tcp_v6_route_req,
865 .init_seq = tcp_v6_init_seq,
866 .init_ts_off = tcp_v6_init_ts_off,
867 .send_synack = tcp_v6_send_synack,
870 static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq,
871 u32 ack, u32 win, u32 tsval, u32 tsecr,
872 int oif, struct tcp_md5sig_key *key, int rst,
873 u8 tclass, __be32 label, u32 priority)
875 const struct tcphdr *th = tcp_hdr(skb);
877 struct sk_buff *buff;
879 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev);
880 struct sock *ctl_sk = net->ipv6.tcp_sk;
881 unsigned int tot_len = sizeof(struct tcphdr);
882 __be32 mrst = 0, *topt;
883 struct dst_entry *dst;
887 tot_len += TCPOLEN_TSTAMP_ALIGNED;
888 #ifdef CONFIG_TCP_MD5SIG
890 tot_len += TCPOLEN_MD5SIG_ALIGNED;
895 mrst = mptcp_reset_option(skb);
898 tot_len += sizeof(__be32);
902 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
907 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
909 t1 = skb_push(buff, tot_len);
910 skb_reset_transport_header(buff);
912 /* Swap the send and the receive. */
913 memset(t1, 0, sizeof(*t1));
914 t1->dest = th->source;
915 t1->source = th->dest;
916 t1->doff = tot_len / 4;
917 t1->seq = htonl(seq);
918 t1->ack_seq = htonl(ack);
919 t1->ack = !rst || !th->ack;
921 t1->window = htons(win);
923 topt = (__be32 *)(t1 + 1);
926 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
927 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
928 *topt++ = htonl(tsval);
929 *topt++ = htonl(tsecr);
935 #ifdef CONFIG_TCP_MD5SIG
937 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
938 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG);
939 tcp_v6_md5_hash_hdr((__u8 *)topt, key,
940 &ipv6_hdr(skb)->saddr,
941 &ipv6_hdr(skb)->daddr, t1);
945 memset(&fl6, 0, sizeof(fl6));
946 fl6.daddr = ipv6_hdr(skb)->saddr;
947 fl6.saddr = ipv6_hdr(skb)->daddr;
948 fl6.flowlabel = label;
950 buff->ip_summed = CHECKSUM_PARTIAL;
953 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr);
955 fl6.flowi6_proto = IPPROTO_TCP;
956 if (rt6_need_strict(&fl6.daddr) && !oif)
957 fl6.flowi6_oif = tcp_v6_iif(skb);
959 if (!oif && netif_index_is_l3_master(net, skb->skb_iif))
962 fl6.flowi6_oif = oif;
966 if (sk->sk_state == TCP_TIME_WAIT) {
967 mark = inet_twsk(sk)->tw_mark;
968 /* autoflowlabel relies on buff->hash */
969 skb_set_hash(buff, inet_twsk(sk)->tw_txhash,
974 buff->tstamp = tcp_transmit_time(sk);
976 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark) ?: mark;
977 fl6.fl6_dport = t1->dest;
978 fl6.fl6_sport = t1->source;
979 fl6.flowi6_uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
980 security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
982 /* Pass a socket to ip6_dst_lookup either it is for RST
983 * Underlying function will use this to retrieve the network
986 dst = ip6_dst_lookup_flow(sock_net(ctl_sk), ctl_sk, &fl6, NULL);
988 skb_dst_set(buff, dst);
989 ip6_xmit(ctl_sk, buff, &fl6, fl6.flowi6_mark, NULL,
990 tclass & ~INET_ECN_MASK, priority);
991 TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
993 TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
1000 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb)
1002 const struct tcphdr *th = tcp_hdr(skb);
1003 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1004 u32 seq = 0, ack_seq = 0;
1005 struct tcp_md5sig_key *key = NULL;
1006 #ifdef CONFIG_TCP_MD5SIG
1007 const __u8 *hash_location = NULL;
1008 unsigned char newhash[16];
1010 struct sock *sk1 = NULL;
1020 /* If sk not NULL, it means we did a successful lookup and incoming
1021 * route had to be correct. prequeue might have dropped our dst.
1023 if (!sk && !ipv6_unicast_destination(skb))
1026 net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev);
1027 #ifdef CONFIG_TCP_MD5SIG
1029 hash_location = tcp_parse_md5sig_option(th);
1030 if (sk && sk_fullsock(sk)) {
1033 /* sdif set, means packet ingressed via a device
1034 * in an L3 domain and inet_iif is set to it.
1036 l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0;
1037 key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr, l3index);
1038 } else if (hash_location) {
1039 int dif = tcp_v6_iif_l3_slave(skb);
1040 int sdif = tcp_v6_sdif(skb);
1044 * active side is lost. Try to find listening socket through
1045 * source port, and then find md5 key through listening socket.
1046 * we are not loose security here:
1047 * Incoming packet is checked with md5 hash with finding key,
1048 * no RST generated if md5 hash doesn't match.
1050 sk1 = inet6_lookup_listener(net,
1051 &tcp_hashinfo, NULL, 0,
1053 th->source, &ipv6h->daddr,
1054 ntohs(th->source), dif, sdif);
1058 /* sdif set, means packet ingressed via a device
1059 * in an L3 domain and dif is set to it.
1061 l3index = tcp_v6_sdif(skb) ? dif : 0;
1063 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr, l3index);
1067 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb);
1068 if (genhash || memcmp(hash_location, newhash, 16) != 0)
1074 seq = ntohl(th->ack_seq);
1076 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len -
1080 oif = sk->sk_bound_dev_if;
1081 if (sk_fullsock(sk)) {
1082 const struct ipv6_pinfo *np = tcp_inet6_sk(sk);
1084 trace_tcp_send_reset(sk, skb);
1086 label = ip6_flowlabel(ipv6h);
1087 priority = sk->sk_priority;
1089 if (sk->sk_state == TCP_TIME_WAIT) {
1090 label = cpu_to_be32(inet_twsk(sk)->tw_flowlabel);
1091 priority = inet_twsk(sk)->tw_priority;
1094 if (net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_TCP_RESET)
1095 label = ip6_flowlabel(ipv6h);
1098 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1,
1099 ipv6_get_dsfield(ipv6h), label, priority);
1101 #ifdef CONFIG_TCP_MD5SIG
1107 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq,
1108 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif,
1109 struct tcp_md5sig_key *key, u8 tclass,
1110 __be32 label, u32 priority)
1112 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0,
1113 tclass, label, priority);
1116 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
1118 struct inet_timewait_sock *tw = inet_twsk(sk);
1119 struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
1121 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
1122 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
1123 tcp_time_stamp_raw() + tcptw->tw_ts_offset,
1124 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw),
1125 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel), tw->tw_priority);
1130 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
1131 struct request_sock *req)
1135 l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0;
1137 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
1138 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
1141 * The window field (SEG.WND) of every outgoing segment, with the
1142 * exception of <SYN> segments, MUST be right-shifted by
1143 * Rcv.Wind.Shift bits:
1145 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ?
1146 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt,
1147 tcp_rsk(req)->rcv_nxt,
1148 req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale,
1149 tcp_time_stamp_raw() + tcp_rsk(req)->ts_off,
1150 req->ts_recent, sk->sk_bound_dev_if,
1151 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->saddr, l3index),
1152 ipv6_get_dsfield(ipv6_hdr(skb)), 0, sk->sk_priority);
1156 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb)
1158 #ifdef CONFIG_SYN_COOKIES
1159 const struct tcphdr *th = tcp_hdr(skb);
1162 sk = cookie_v6_check(sk, skb);
1167 u16 tcp_v6_get_syncookie(struct sock *sk, struct ipv6hdr *iph,
1168 struct tcphdr *th, u32 *cookie)
1171 #ifdef CONFIG_SYN_COOKIES
1172 mss = tcp_get_syncookie_mss(&tcp6_request_sock_ops,
1173 &tcp_request_sock_ipv6_ops, sk, th);
1175 *cookie = __cookie_v6_init_sequence(iph, th, &mss);
1176 tcp_synq_overflow(sk);
1182 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
1184 if (skb->protocol == htons(ETH_P_IP))
1185 return tcp_v4_conn_request(sk, skb);
1187 if (!ipv6_unicast_destination(skb))
1190 if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
1191 __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
1195 return tcp_conn_request(&tcp6_request_sock_ops,
1196 &tcp_request_sock_ipv6_ops, sk, skb);
1200 return 0; /* don't send reset */
1203 static void tcp_v6_restore_cb(struct sk_buff *skb)
1205 /* We need to move header back to the beginning if xfrm6_policy_check()
1206 * and tcp_v6_fill_cb() are going to be called again.
1207 * ip6_datagram_recv_specific_ctl() also expects IP6CB to be there.
1209 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6,
1210 sizeof(struct inet6_skb_parm));
1213 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
1214 struct request_sock *req,
1215 struct dst_entry *dst,
1216 struct request_sock *req_unhash,
1219 struct inet_request_sock *ireq;
1220 struct ipv6_pinfo *newnp;
1221 const struct ipv6_pinfo *np = tcp_inet6_sk(sk);
1222 struct ipv6_txoptions *opt;
1223 struct inet_sock *newinet;
1224 bool found_dup_sk = false;
1225 struct tcp_sock *newtp;
1227 #ifdef CONFIG_TCP_MD5SIG
1228 struct tcp_md5sig_key *key;
1233 if (skb->protocol == htons(ETH_P_IP)) {
1238 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst,
1239 req_unhash, own_req);
1244 inet_sk(newsk)->pinet6 = tcp_inet6_sk(newsk);
1246 newinet = inet_sk(newsk);
1247 newnp = tcp_inet6_sk(newsk);
1248 newtp = tcp_sk(newsk);
1250 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1252 newnp->saddr = newsk->sk_v6_rcv_saddr;
1254 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped;
1255 if (sk_is_mptcp(newsk))
1256 mptcpv6_handle_mapped(newsk, true);
1257 newsk->sk_backlog_rcv = tcp_v4_do_rcv;
1258 #ifdef CONFIG_TCP_MD5SIG
1259 newtp->af_specific = &tcp_sock_ipv6_mapped_specific;
1262 newnp->ipv6_mc_list = NULL;
1263 newnp->ipv6_ac_list = NULL;
1264 newnp->ipv6_fl_list = NULL;
1265 newnp->pktoptions = NULL;
1267 newnp->mcast_oif = inet_iif(skb);
1268 newnp->mcast_hops = ip_hdr(skb)->ttl;
1269 newnp->rcv_flowinfo = 0;
1271 newnp->flow_label = 0;
1274 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1275 * here, tcp_create_openreq_child now does this for us, see the comment in
1276 * that function for the gory details. -acme
1279 /* It is tricky place. Until this moment IPv4 tcp
1280 worked with IPv6 icsk.icsk_af_ops.
1283 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
1288 ireq = inet_rsk(req);
1290 if (sk_acceptq_is_full(sk))
1294 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP);
1299 newsk = tcp_create_openreq_child(sk, req, skb);
1304 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1305 * count here, tcp_create_openreq_child now does this for us, see the
1306 * comment in that function for the gory details. -acme
1309 newsk->sk_gso_type = SKB_GSO_TCPV6;
1310 ip6_dst_store(newsk, dst, NULL, NULL);
1311 inet6_sk_rx_dst_set(newsk, skb);
1313 inet_sk(newsk)->pinet6 = tcp_inet6_sk(newsk);
1315 newtp = tcp_sk(newsk);
1316 newinet = inet_sk(newsk);
1317 newnp = tcp_inet6_sk(newsk);
1319 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1321 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr;
1322 newnp->saddr = ireq->ir_v6_loc_addr;
1323 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
1324 newsk->sk_bound_dev_if = ireq->ir_iif;
1326 /* Now IPv6 options...
1328 First: no IPv4 options.
1330 newinet->inet_opt = NULL;
1331 newnp->ipv6_mc_list = NULL;
1332 newnp->ipv6_ac_list = NULL;
1333 newnp->ipv6_fl_list = NULL;
1336 newnp->rxopt.all = np->rxopt.all;
1338 newnp->pktoptions = NULL;
1340 newnp->mcast_oif = tcp_v6_iif(skb);
1341 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
1342 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb));
1344 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb));
1346 /* Set ToS of the new socket based upon the value of incoming SYN.
1347 * ECT bits are set later in tcp_init_transfer().
1349 if (sock_net(sk)->ipv4.sysctl_tcp_reflect_tos)
1350 newnp->tclass = tcp_rsk(req)->syn_tos & ~INET_ECN_MASK;
1352 /* Clone native IPv6 options from listening socket (if any)
1354 Yes, keeping reference count would be much more clever,
1355 but we make one more one thing there: reattach optmem
1358 opt = ireq->ipv6_opt;
1360 opt = rcu_dereference(np->opt);
1362 opt = ipv6_dup_options(newsk, opt);
1363 RCU_INIT_POINTER(newnp->opt, opt);
1365 inet_csk(newsk)->icsk_ext_hdr_len = 0;
1367 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen +
1370 tcp_ca_openreq_child(newsk, dst);
1372 tcp_sync_mss(newsk, dst_mtu(dst));
1373 newtp->advmss = tcp_mss_clamp(tcp_sk(sk), dst_metric_advmss(dst));
1375 tcp_initialize_rcv_mss(newsk);
1377 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
1378 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
1380 #ifdef CONFIG_TCP_MD5SIG
1381 l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
1383 /* Copy over the MD5 key from the original socket */
1384 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr, l3index);
1386 /* We're using one, so create a matching key
1387 * on the newsk structure. If we fail to get
1388 * memory, then we end up not copying the key
1391 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr,
1392 AF_INET6, 128, l3index, key->key, key->keylen,
1393 sk_gfp_mask(sk, GFP_ATOMIC));
1397 if (__inet_inherit_port(sk, newsk) < 0) {
1398 inet_csk_prepare_forced_close(newsk);
1402 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash),
1405 tcp_move_syn(newtp, req);
1407 /* Clone pktoptions received with SYN, if we own the req */
1408 if (ireq->pktopts) {
1409 newnp->pktoptions = skb_clone(ireq->pktopts,
1410 sk_gfp_mask(sk, GFP_ATOMIC));
1411 consume_skb(ireq->pktopts);
1412 ireq->pktopts = NULL;
1413 if (newnp->pktoptions) {
1414 tcp_v6_restore_cb(newnp->pktoptions);
1415 skb_set_owner_r(newnp->pktoptions, newsk);
1419 if (!req_unhash && found_dup_sk) {
1420 /* This code path should only be executed in the
1421 * syncookie case only
1423 bh_unlock_sock(newsk);
1432 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
1440 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
1442 /* The socket must have it's spinlock held when we get
1443 * here, unless it is a TCP_LISTEN socket.
1445 * We have a potential double-lock case here, so even when
1446 * doing backlog processing we use the BH locking scheme.
1447 * This is because we cannot sleep with the original spinlock
1450 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
1452 struct ipv6_pinfo *np = tcp_inet6_sk(sk);
1453 struct sk_buff *opt_skb = NULL;
1454 struct tcp_sock *tp;
1456 /* Imagine: socket is IPv6. IPv4 packet arrives,
1457 goes to IPv4 receive handler and backlogged.
1458 From backlog it always goes here. Kerboom...
1459 Fortunately, tcp_rcv_established and rcv_established
1460 handle them correctly, but it is not case with
1461 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1464 if (skb->protocol == htons(ETH_P_IP))
1465 return tcp_v4_do_rcv(sk, skb);
1468 * socket locking is here for SMP purposes as backlog rcv
1469 * is currently called with bh processing disabled.
1472 /* Do Stevens' IPV6_PKTOPTIONS.
1474 Yes, guys, it is the only place in our code, where we
1475 may make it not affecting IPv4.
1476 The rest of code is protocol independent,
1477 and I do not like idea to uglify IPv4.
1479 Actually, all the idea behind IPV6_PKTOPTIONS
1480 looks not very well thought. For now we latch
1481 options, received in the last packet, enqueued
1482 by tcp. Feel free to propose better solution.
1486 opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
1488 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
1489 struct dst_entry *dst = sk->sk_rx_dst;
1491 sock_rps_save_rxhash(sk, skb);
1492 sk_mark_napi_id(sk, skb);
1494 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
1495 INDIRECT_CALL_1(dst->ops->check, ip6_dst_check,
1496 dst, np->rx_dst_cookie) == NULL) {
1498 sk->sk_rx_dst = NULL;
1502 tcp_rcv_established(sk, skb);
1504 goto ipv6_pktoptions;
1508 if (tcp_checksum_complete(skb))
1511 if (sk->sk_state == TCP_LISTEN) {
1512 struct sock *nsk = tcp_v6_cookie_check(sk, skb);
1518 if (tcp_child_process(sk, nsk, skb))
1521 __kfree_skb(opt_skb);
1525 sock_rps_save_rxhash(sk, skb);
1527 if (tcp_rcv_state_process(sk, skb))
1530 goto ipv6_pktoptions;
1534 tcp_v6_send_reset(sk, skb);
1537 __kfree_skb(opt_skb);
1541 TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
1542 TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
1547 /* Do you ask, what is it?
1549 1. skb was enqueued by tcp.
1550 2. skb is added to tail of read queue, rather than out of order.
1551 3. socket is not in passive state.
1552 4. Finally, it really contains options, which user wants to receive.
1555 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
1556 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
1557 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
1558 np->mcast_oif = tcp_v6_iif(opt_skb);
1559 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
1560 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
1561 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)
1562 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
1564 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
1565 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) {
1566 skb_set_owner_r(opt_skb, sk);
1567 tcp_v6_restore_cb(opt_skb);
1568 opt_skb = xchg(&np->pktoptions, opt_skb);
1570 __kfree_skb(opt_skb);
1571 opt_skb = xchg(&np->pktoptions, NULL);
1579 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr,
1580 const struct tcphdr *th)
1582 /* This is tricky: we move IP6CB at its correct location into
1583 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because
1584 * _decode_session6() uses IP6CB().
1585 * barrier() makes sure compiler won't play aliasing games.
1587 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb),
1588 sizeof(struct inet6_skb_parm));
1591 TCP_SKB_CB(skb)->seq = ntohl(th->seq);
1592 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
1593 skb->len - th->doff*4);
1594 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
1595 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
1596 TCP_SKB_CB(skb)->tcp_tw_isn = 0;
1597 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr);
1598 TCP_SKB_CB(skb)->sacked = 0;
1599 TCP_SKB_CB(skb)->has_rxtstamp =
1600 skb->tstamp || skb_hwtstamps(skb)->hwtstamp;
1603 INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
1605 struct sk_buff *skb_to_free;
1606 int sdif = inet6_sdif(skb);
1607 int dif = inet6_iif(skb);
1608 const struct tcphdr *th;
1609 const struct ipv6hdr *hdr;
1613 struct net *net = dev_net(skb->dev);
1615 if (skb->pkt_type != PACKET_HOST)
1619 * Count it even if it's bad.
1621 __TCP_INC_STATS(net, TCP_MIB_INSEGS);
1623 if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
1626 th = (const struct tcphdr *)skb->data;
1628 if (unlikely(th->doff < sizeof(struct tcphdr)/4))
1630 if (!pskb_may_pull(skb, th->doff*4))
1633 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo))
1636 th = (const struct tcphdr *)skb->data;
1637 hdr = ipv6_hdr(skb);
1640 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th),
1641 th->source, th->dest, inet6_iif(skb), sdif,
1647 if (sk->sk_state == TCP_TIME_WAIT)
1650 if (sk->sk_state == TCP_NEW_SYN_RECV) {
1651 struct request_sock *req = inet_reqsk(sk);
1652 bool req_stolen = false;
1655 sk = req->rsk_listener;
1656 if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif)) {
1657 sk_drops_add(sk, skb);
1661 if (tcp_checksum_complete(skb)) {
1665 if (unlikely(sk->sk_state != TCP_LISTEN)) {
1666 inet_csk_reqsk_queue_drop_and_put(sk, req);
1672 if (!tcp_filter(sk, skb)) {
1673 th = (const struct tcphdr *)skb->data;
1674 hdr = ipv6_hdr(skb);
1675 tcp_v6_fill_cb(skb, hdr, th);
1676 nsk = tcp_check_req(sk, skb, req, false, &req_stolen);
1681 /* Another cpu got exclusive access to req
1682 * and created a full blown socket.
1683 * Try to feed this packet to this socket
1684 * instead of discarding it.
1686 tcp_v6_restore_cb(skb);
1690 goto discard_and_relse;
1694 tcp_v6_restore_cb(skb);
1695 } else if (tcp_child_process(sk, nsk, skb)) {
1696 tcp_v6_send_reset(nsk, skb);
1697 goto discard_and_relse;
1703 if (hdr->hop_limit < tcp_inet6_sk(sk)->min_hopcount) {
1704 __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP);
1705 goto discard_and_relse;
1708 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
1709 goto discard_and_relse;
1711 if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif))
1712 goto discard_and_relse;
1714 if (tcp_filter(sk, skb))
1715 goto discard_and_relse;
1716 th = (const struct tcphdr *)skb->data;
1717 hdr = ipv6_hdr(skb);
1718 tcp_v6_fill_cb(skb, hdr, th);
1722 if (sk->sk_state == TCP_LISTEN) {
1723 ret = tcp_v6_do_rcv(sk, skb);
1724 goto put_and_return;
1727 sk_incoming_cpu_update(sk);
1729 bh_lock_sock_nested(sk);
1730 tcp_segs_in(tcp_sk(sk), skb);
1732 if (!sock_owned_by_user(sk)) {
1733 skb_to_free = sk->sk_rx_skb_cache;
1734 sk->sk_rx_skb_cache = NULL;
1735 ret = tcp_v6_do_rcv(sk, skb);
1737 if (tcp_add_backlog(sk, skb))
1738 goto discard_and_relse;
1743 __kfree_skb(skb_to_free);
1747 return ret ? -1 : 0;
1750 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1753 tcp_v6_fill_cb(skb, hdr, th);
1755 if (tcp_checksum_complete(skb)) {
1757 __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
1759 __TCP_INC_STATS(net, TCP_MIB_INERRS);
1761 tcp_v6_send_reset(NULL, skb);
1769 sk_drops_add(sk, skb);
1775 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1776 inet_twsk_put(inet_twsk(sk));
1780 tcp_v6_fill_cb(skb, hdr, th);
1782 if (tcp_checksum_complete(skb)) {
1783 inet_twsk_put(inet_twsk(sk));
1787 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) {
1792 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo,
1793 skb, __tcp_hdrlen(th),
1794 &ipv6_hdr(skb)->saddr, th->source,
1795 &ipv6_hdr(skb)->daddr,
1797 tcp_v6_iif_l3_slave(skb),
1800 struct inet_timewait_sock *tw = inet_twsk(sk);
1801 inet_twsk_deschedule_put(tw);
1803 tcp_v6_restore_cb(skb);
1811 tcp_v6_timewait_ack(sk, skb);
1814 tcp_v6_send_reset(sk, skb);
1815 inet_twsk_deschedule_put(inet_twsk(sk));
1817 case TCP_TW_SUCCESS:
1823 INDIRECT_CALLABLE_SCOPE void tcp_v6_early_demux(struct sk_buff *skb)
1825 const struct ipv6hdr *hdr;
1826 const struct tcphdr *th;
1829 if (skb->pkt_type != PACKET_HOST)
1832 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr)))
1835 hdr = ipv6_hdr(skb);
1838 if (th->doff < sizeof(struct tcphdr) / 4)
1841 /* Note : We use inet6_iif() here, not tcp_v6_iif() */
1842 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo,
1843 &hdr->saddr, th->source,
1844 &hdr->daddr, ntohs(th->dest),
1845 inet6_iif(skb), inet6_sdif(skb));
1848 skb->destructor = sock_edemux;
1849 if (sk_fullsock(sk)) {
1850 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst);
1853 dst = dst_check(dst, tcp_inet6_sk(sk)->rx_dst_cookie);
1855 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif)
1856 skb_dst_set_noref(skb, dst);
1861 static struct timewait_sock_ops tcp6_timewait_sock_ops = {
1862 .twsk_obj_size = sizeof(struct tcp6_timewait_sock),
1863 .twsk_unique = tcp_twsk_unique,
1864 .twsk_destructor = tcp_twsk_destructor,
1867 INDIRECT_CALLABLE_SCOPE void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
1869 struct ipv6_pinfo *np = inet6_sk(sk);
1871 __tcp_v6_send_check(skb, &np->saddr, &sk->sk_v6_daddr);
1874 const struct inet_connection_sock_af_ops ipv6_specific = {
1875 .queue_xmit = inet6_csk_xmit,
1876 .send_check = tcp_v6_send_check,
1877 .rebuild_header = inet6_sk_rebuild_header,
1878 .sk_rx_dst_set = inet6_sk_rx_dst_set,
1879 .conn_request = tcp_v6_conn_request,
1880 .syn_recv_sock = tcp_v6_syn_recv_sock,
1881 .net_header_len = sizeof(struct ipv6hdr),
1882 .net_frag_header_len = sizeof(struct frag_hdr),
1883 .setsockopt = ipv6_setsockopt,
1884 .getsockopt = ipv6_getsockopt,
1885 .addr2sockaddr = inet6_csk_addr2sockaddr,
1886 .sockaddr_len = sizeof(struct sockaddr_in6),
1887 .mtu_reduced = tcp_v6_mtu_reduced,
1890 #ifdef CONFIG_TCP_MD5SIG
1891 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = {
1892 .md5_lookup = tcp_v6_md5_lookup,
1893 .calc_md5_hash = tcp_v6_md5_hash_skb,
1894 .md5_parse = tcp_v6_parse_md5_keys,
1899 * TCP over IPv4 via INET6 API
1901 static const struct inet_connection_sock_af_ops ipv6_mapped = {
1902 .queue_xmit = ip_queue_xmit,
1903 .send_check = tcp_v4_send_check,
1904 .rebuild_header = inet_sk_rebuild_header,
1905 .sk_rx_dst_set = inet_sk_rx_dst_set,
1906 .conn_request = tcp_v6_conn_request,
1907 .syn_recv_sock = tcp_v6_syn_recv_sock,
1908 .net_header_len = sizeof(struct iphdr),
1909 .setsockopt = ipv6_setsockopt,
1910 .getsockopt = ipv6_getsockopt,
1911 .addr2sockaddr = inet6_csk_addr2sockaddr,
1912 .sockaddr_len = sizeof(struct sockaddr_in6),
1913 .mtu_reduced = tcp_v4_mtu_reduced,
1916 #ifdef CONFIG_TCP_MD5SIG
1917 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = {
1918 .md5_lookup = tcp_v4_md5_lookup,
1919 .calc_md5_hash = tcp_v4_md5_hash_skb,
1920 .md5_parse = tcp_v6_parse_md5_keys,
1924 /* NOTE: A lot of things set to zero explicitly by call to
1925 * sk_alloc() so need not be done here.
1927 static int tcp_v6_init_sock(struct sock *sk)
1929 struct inet_connection_sock *icsk = inet_csk(sk);
1933 icsk->icsk_af_ops = &ipv6_specific;
1935 #ifdef CONFIG_TCP_MD5SIG
1936 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific;
1942 static void tcp_v6_destroy_sock(struct sock *sk)
1944 tcp_v4_destroy_sock(sk);
1945 inet6_destroy_sock(sk);
1948 #ifdef CONFIG_PROC_FS
1949 /* Proc filesystem TCPv6 sock list dumping. */
1950 static void get_openreq6(struct seq_file *seq,
1951 const struct request_sock *req, int i)
1953 long ttd = req->rsk_timer.expires - jiffies;
1954 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr;
1955 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr;
1961 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1962 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n",
1964 src->s6_addr32[0], src->s6_addr32[1],
1965 src->s6_addr32[2], src->s6_addr32[3],
1966 inet_rsk(req)->ir_num,
1967 dest->s6_addr32[0], dest->s6_addr32[1],
1968 dest->s6_addr32[2], dest->s6_addr32[3],
1969 ntohs(inet_rsk(req)->ir_rmt_port),
1971 0, 0, /* could print option size, but that is af dependent. */
1972 1, /* timers active (only the expire timer) */
1973 jiffies_to_clock_t(ttd),
1975 from_kuid_munged(seq_user_ns(seq),
1976 sock_i_uid(req->rsk_listener)),
1977 0, /* non standard timer */
1978 0, /* open_requests have no inode */
1982 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
1984 const struct in6_addr *dest, *src;
1987 unsigned long timer_expires;
1988 const struct inet_sock *inet = inet_sk(sp);
1989 const struct tcp_sock *tp = tcp_sk(sp);
1990 const struct inet_connection_sock *icsk = inet_csk(sp);
1991 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq;
1995 dest = &sp->sk_v6_daddr;
1996 src = &sp->sk_v6_rcv_saddr;
1997 destp = ntohs(inet->inet_dport);
1998 srcp = ntohs(inet->inet_sport);
2000 if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
2001 icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
2002 icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
2004 timer_expires = icsk->icsk_timeout;
2005 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
2007 timer_expires = icsk->icsk_timeout;
2008 } else if (timer_pending(&sp->sk_timer)) {
2010 timer_expires = sp->sk_timer.expires;
2013 timer_expires = jiffies;
2016 state = inet_sk_state_load(sp);
2017 if (state == TCP_LISTEN)
2018 rx_queue = READ_ONCE(sp->sk_ack_backlog);
2020 /* Because we don't lock the socket,
2021 * we might find a transient negative value.
2023 rx_queue = max_t(int, READ_ONCE(tp->rcv_nxt) -
2024 READ_ONCE(tp->copied_seq), 0);
2027 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2028 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
2030 src->s6_addr32[0], src->s6_addr32[1],
2031 src->s6_addr32[2], src->s6_addr32[3], srcp,
2032 dest->s6_addr32[0], dest->s6_addr32[1],
2033 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2035 READ_ONCE(tp->write_seq) - tp->snd_una,
2038 jiffies_delta_to_clock_t(timer_expires - jiffies),
2039 icsk->icsk_retransmits,
2040 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
2041 icsk->icsk_probes_out,
2043 refcount_read(&sp->sk_refcnt), sp,
2044 jiffies_to_clock_t(icsk->icsk_rto),
2045 jiffies_to_clock_t(icsk->icsk_ack.ato),
2046 (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sp),
2048 state == TCP_LISTEN ?
2049 fastopenq->max_qlen :
2050 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)
2054 static void get_timewait6_sock(struct seq_file *seq,
2055 struct inet_timewait_sock *tw, int i)
2057 long delta = tw->tw_timer.expires - jiffies;
2058 const struct in6_addr *dest, *src;
2061 dest = &tw->tw_v6_daddr;
2062 src = &tw->tw_v6_rcv_saddr;
2063 destp = ntohs(tw->tw_dport);
2064 srcp = ntohs(tw->tw_sport);
2067 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2068 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
2070 src->s6_addr32[0], src->s6_addr32[1],
2071 src->s6_addr32[2], src->s6_addr32[3], srcp,
2072 dest->s6_addr32[0], dest->s6_addr32[1],
2073 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2074 tw->tw_substate, 0, 0,
2075 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0,
2076 refcount_read(&tw->tw_refcnt), tw);
2079 static int tcp6_seq_show(struct seq_file *seq, void *v)
2081 struct tcp_iter_state *st;
2082 struct sock *sk = v;
2084 if (v == SEQ_START_TOKEN) {
2089 "st tx_queue rx_queue tr tm->when retrnsmt"
2090 " uid timeout inode\n");
2095 if (sk->sk_state == TCP_TIME_WAIT)
2096 get_timewait6_sock(seq, v, st->num);
2097 else if (sk->sk_state == TCP_NEW_SYN_RECV)
2098 get_openreq6(seq, v, st->num);
2100 get_tcp6_sock(seq, v, st->num);
2105 static const struct seq_operations tcp6_seq_ops = {
2106 .show = tcp6_seq_show,
2107 .start = tcp_seq_start,
2108 .next = tcp_seq_next,
2109 .stop = tcp_seq_stop,
2112 static struct tcp_seq_afinfo tcp6_seq_afinfo = {
2116 int __net_init tcp6_proc_init(struct net *net)
2118 if (!proc_create_net_data("tcp6", 0444, net->proc_net, &tcp6_seq_ops,
2119 sizeof(struct tcp_iter_state), &tcp6_seq_afinfo))
2124 void tcp6_proc_exit(struct net *net)
2126 remove_proc_entry("tcp6", net->proc_net);
2130 struct proto tcpv6_prot = {
2132 .owner = THIS_MODULE,
2134 .pre_connect = tcp_v6_pre_connect,
2135 .connect = tcp_v6_connect,
2136 .disconnect = tcp_disconnect,
2137 .accept = inet_csk_accept,
2139 .init = tcp_v6_init_sock,
2140 .destroy = tcp_v6_destroy_sock,
2141 .shutdown = tcp_shutdown,
2142 .setsockopt = tcp_setsockopt,
2143 .getsockopt = tcp_getsockopt,
2144 .bpf_bypass_getsockopt = tcp_bpf_bypass_getsockopt,
2145 .keepalive = tcp_set_keepalive,
2146 .recvmsg = tcp_recvmsg,
2147 .sendmsg = tcp_sendmsg,
2148 .sendpage = tcp_sendpage,
2149 .backlog_rcv = tcp_v6_do_rcv,
2150 .release_cb = tcp_release_cb,
2152 .unhash = inet_unhash,
2153 .get_port = inet_csk_get_port,
2154 #ifdef CONFIG_BPF_SYSCALL
2155 .psock_update_sk_prot = tcp_bpf_update_proto,
2157 .enter_memory_pressure = tcp_enter_memory_pressure,
2158 .leave_memory_pressure = tcp_leave_memory_pressure,
2159 .stream_memory_free = tcp_stream_memory_free,
2160 .sockets_allocated = &tcp_sockets_allocated,
2161 .memory_allocated = &tcp_memory_allocated,
2162 .memory_pressure = &tcp_memory_pressure,
2163 .orphan_count = &tcp_orphan_count,
2164 .sysctl_mem = sysctl_tcp_mem,
2165 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem),
2166 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem),
2167 .max_header = MAX_TCP_HEADER,
2168 .obj_size = sizeof(struct tcp6_sock),
2169 .slab_flags = SLAB_TYPESAFE_BY_RCU,
2170 .twsk_prot = &tcp6_timewait_sock_ops,
2171 .rsk_prot = &tcp6_request_sock_ops,
2172 .h.hashinfo = &tcp_hashinfo,
2173 .no_autobind = true,
2174 .diag_destroy = tcp_abort,
2176 EXPORT_SYMBOL_GPL(tcpv6_prot);
2178 /* thinking of making this const? Don't.
2179 * early_demux can change based on sysctl.
2181 static struct inet6_protocol tcpv6_protocol = {
2182 .early_demux = tcp_v6_early_demux,
2183 .early_demux_handler = tcp_v6_early_demux,
2184 .handler = tcp_v6_rcv,
2185 .err_handler = tcp_v6_err,
2186 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
2189 static struct inet_protosw tcpv6_protosw = {
2190 .type = SOCK_STREAM,
2191 .protocol = IPPROTO_TCP,
2192 .prot = &tcpv6_prot,
2193 .ops = &inet6_stream_ops,
2194 .flags = INET_PROTOSW_PERMANENT |
2198 static int __net_init tcpv6_net_init(struct net *net)
2200 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6,
2201 SOCK_RAW, IPPROTO_TCP, net);
2204 static void __net_exit tcpv6_net_exit(struct net *net)
2206 inet_ctl_sock_destroy(net->ipv6.tcp_sk);
2209 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
2211 inet_twsk_purge(&tcp_hashinfo, AF_INET6);
2214 static struct pernet_operations tcpv6_net_ops = {
2215 .init = tcpv6_net_init,
2216 .exit = tcpv6_net_exit,
2217 .exit_batch = tcpv6_net_exit_batch,
2220 int __init tcpv6_init(void)
2224 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP);
2228 /* register inet6 protocol */
2229 ret = inet6_register_protosw(&tcpv6_protosw);
2231 goto out_tcpv6_protocol;
2233 ret = register_pernet_subsys(&tcpv6_net_ops);
2235 goto out_tcpv6_protosw;
2237 ret = mptcpv6_init();
2239 goto out_tcpv6_pernet_subsys;
2244 out_tcpv6_pernet_subsys:
2245 unregister_pernet_subsys(&tcpv6_net_ops);
2247 inet6_unregister_protosw(&tcpv6_protosw);
2249 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);
2253 void tcpv6_exit(void)
2255 unregister_pernet_subsys(&tcpv6_net_ops);
2256 inet6_unregister_protosw(&tcpv6_protosw);
2257 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);