3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
10 * linux/net/ipv4/tcp_input.c
11 * linux/net/ipv4/tcp_output.c
14 * Hideaki YOSHIFUJI : sin6_scope_id support
15 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
16 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
17 * a single port at the same time.
18 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file.
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
26 #include <linux/bottom_half.h>
27 #include <linux/module.h>
28 #include <linux/errno.h>
29 #include <linux/types.h>
30 #include <linux/socket.h>
31 #include <linux/sockios.h>
32 #include <linux/net.h>
33 #include <linux/jiffies.h>
35 #include <linux/in6.h>
36 #include <linux/netdevice.h>
37 #include <linux/init.h>
38 #include <linux/jhash.h>
39 #include <linux/ipsec.h>
40 #include <linux/times.h>
41 #include <linux/slab.h>
42 #include <linux/uaccess.h>
43 #include <linux/ipv6.h>
44 #include <linux/icmpv6.h>
45 #include <linux/random.h>
48 #include <net/ndisc.h>
49 #include <net/inet6_hashtables.h>
50 #include <net/inet6_connection_sock.h>
52 #include <net/transp_v6.h>
53 #include <net/addrconf.h>
54 #include <net/ip6_route.h>
55 #include <net/ip6_checksum.h>
56 #include <net/inet_ecn.h>
57 #include <net/protocol.h>
60 #include <net/dsfield.h>
61 #include <net/timewait_sock.h>
62 #include <net/inet_common.h>
63 #include <net/secure_seq.h>
64 #include <net/busy_poll.h>
66 #include <linux/proc_fs.h>
67 #include <linux/seq_file.h>
69 #include <crypto/hash.h>
70 #include <linux/scatterlist.h>
72 static void tcp_v6_send_reset(const struct sock
*sk
, struct sk_buff
*skb
);
73 static void tcp_v6_reqsk_send_ack(const struct sock
*sk
, struct sk_buff
*skb
,
74 struct request_sock
*req
);
76 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
);
78 static const struct inet_connection_sock_af_ops ipv6_mapped
;
79 static const struct inet_connection_sock_af_ops ipv6_specific
;
80 #ifdef CONFIG_TCP_MD5SIG
81 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
;
82 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
;
84 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(const struct sock
*sk
,
85 const struct in6_addr
*addr
)
91 static void inet6_sk_rx_dst_set(struct sock
*sk
, const struct sk_buff
*skb
)
93 struct dst_entry
*dst
= skb_dst(skb
);
95 if (dst
&& dst_hold_safe(dst
)) {
96 const struct rt6_info
*rt
= (const struct rt6_info
*)dst
;
99 inet_sk(sk
)->rx_dst_ifindex
= skb
->skb_iif
;
100 inet6_sk(sk
)->rx_dst_cookie
= rt6_get_cookie(rt
);
104 static u32
tcp_v6_init_sequence(const struct sk_buff
*skb
, u32
*tsoff
)
106 return secure_tcpv6_sequence_number(ipv6_hdr(skb
)->daddr
.s6_addr32
,
107 ipv6_hdr(skb
)->saddr
.s6_addr32
,
109 tcp_hdr(skb
)->source
, tsoff
);
112 static int tcp_v6_connect(struct sock
*sk
, struct sockaddr
*uaddr
,
115 struct sockaddr_in6
*usin
= (struct sockaddr_in6
*) uaddr
;
116 struct inet_sock
*inet
= inet_sk(sk
);
117 struct inet_connection_sock
*icsk
= inet_csk(sk
);
118 struct ipv6_pinfo
*np
= inet6_sk(sk
);
119 struct tcp_sock
*tp
= tcp_sk(sk
);
120 struct in6_addr
*saddr
= NULL
, *final_p
, final
;
121 struct ipv6_txoptions
*opt
;
123 struct dst_entry
*dst
;
127 if (addr_len
< SIN6_LEN_RFC2133
)
130 if (usin
->sin6_family
!= AF_INET6
)
131 return -EAFNOSUPPORT
;
133 memset(&fl6
, 0, sizeof(fl6
));
136 fl6
.flowlabel
= usin
->sin6_flowinfo
&IPV6_FLOWINFO_MASK
;
137 IP6_ECN_flow_init(fl6
.flowlabel
);
138 if (fl6
.flowlabel
&IPV6_FLOWLABEL_MASK
) {
139 struct ip6_flowlabel
*flowlabel
;
140 flowlabel
= fl6_sock_lookup(sk
, fl6
.flowlabel
);
143 fl6_sock_release(flowlabel
);
148 * connect() to INADDR_ANY means loopback (BSD'ism).
151 if (ipv6_addr_any(&usin
->sin6_addr
))
152 usin
->sin6_addr
.s6_addr
[15] = 0x1;
154 addr_type
= ipv6_addr_type(&usin
->sin6_addr
);
156 if (addr_type
& IPV6_ADDR_MULTICAST
)
159 if (addr_type
&IPV6_ADDR_LINKLOCAL
) {
160 if (addr_len
>= sizeof(struct sockaddr_in6
) &&
161 usin
->sin6_scope_id
) {
162 /* If interface is set while binding, indices
165 if (sk
->sk_bound_dev_if
&&
166 sk
->sk_bound_dev_if
!= usin
->sin6_scope_id
)
169 sk
->sk_bound_dev_if
= usin
->sin6_scope_id
;
172 /* Connect to link-local address requires an interface */
173 if (!sk
->sk_bound_dev_if
)
177 if (tp
->rx_opt
.ts_recent_stamp
&&
178 !ipv6_addr_equal(&sk
->sk_v6_daddr
, &usin
->sin6_addr
)) {
179 tp
->rx_opt
.ts_recent
= 0;
180 tp
->rx_opt
.ts_recent_stamp
= 0;
184 sk
->sk_v6_daddr
= usin
->sin6_addr
;
185 np
->flow_label
= fl6
.flowlabel
;
191 if (addr_type
== IPV6_ADDR_MAPPED
) {
192 u32 exthdrlen
= icsk
->icsk_ext_hdr_len
;
193 struct sockaddr_in sin
;
195 SOCK_DEBUG(sk
, "connect: ipv4 mapped\n");
197 if (__ipv6_only_sock(sk
))
200 sin
.sin_family
= AF_INET
;
201 sin
.sin_port
= usin
->sin6_port
;
202 sin
.sin_addr
.s_addr
= usin
->sin6_addr
.s6_addr32
[3];
204 icsk
->icsk_af_ops
= &ipv6_mapped
;
205 sk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
206 #ifdef CONFIG_TCP_MD5SIG
207 tp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
210 err
= tcp_v4_connect(sk
, (struct sockaddr
*)&sin
, sizeof(sin
));
213 icsk
->icsk_ext_hdr_len
= exthdrlen
;
214 icsk
->icsk_af_ops
= &ipv6_specific
;
215 sk
->sk_backlog_rcv
= tcp_v6_do_rcv
;
216 #ifdef CONFIG_TCP_MD5SIG
217 tp
->af_specific
= &tcp_sock_ipv6_specific
;
221 np
->saddr
= sk
->sk_v6_rcv_saddr
;
226 if (!ipv6_addr_any(&sk
->sk_v6_rcv_saddr
))
227 saddr
= &sk
->sk_v6_rcv_saddr
;
229 fl6
.flowi6_proto
= IPPROTO_TCP
;
230 fl6
.daddr
= sk
->sk_v6_daddr
;
231 fl6
.saddr
= saddr
? *saddr
: np
->saddr
;
232 fl6
.flowi6_oif
= sk
->sk_bound_dev_if
;
233 fl6
.flowi6_mark
= sk
->sk_mark
;
234 fl6
.fl6_dport
= usin
->sin6_port
;
235 fl6
.fl6_sport
= inet
->inet_sport
;
236 fl6
.flowi6_uid
= sk
->sk_uid
;
238 opt
= rcu_dereference_protected(np
->opt
, lockdep_sock_is_held(sk
));
239 final_p
= fl6_update_dst(&fl6
, opt
, &final
);
241 security_sk_classify_flow(sk
, flowi6_to_flowi(&fl6
));
243 dst
= ip6_dst_lookup_flow(sk
, &fl6
, final_p
);
251 sk
->sk_v6_rcv_saddr
= *saddr
;
254 /* set the source address */
256 inet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
258 sk
->sk_gso_type
= SKB_GSO_TCPV6
;
259 ip6_dst_store(sk
, dst
, NULL
, NULL
);
261 if (tcp_death_row
.sysctl_tw_recycle
&&
262 !tp
->rx_opt
.ts_recent_stamp
&&
263 ipv6_addr_equal(&fl6
.daddr
, &sk
->sk_v6_daddr
))
264 tcp_fetch_timewait_stamp(sk
, dst
);
266 icsk
->icsk_ext_hdr_len
= 0;
268 icsk
->icsk_ext_hdr_len
= opt
->opt_flen
+
271 tp
->rx_opt
.mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) - sizeof(struct ipv6hdr
);
273 inet
->inet_dport
= usin
->sin6_port
;
275 tcp_set_state(sk
, TCP_SYN_SENT
);
276 err
= inet6_hash_connect(&tcp_death_row
, sk
);
282 if (!tp
->write_seq
&& likely(!tp
->repair
))
283 tp
->write_seq
= secure_tcpv6_sequence_number(np
->saddr
.s6_addr32
,
284 sk
->sk_v6_daddr
.s6_addr32
,
289 err
= tcp_connect(sk
);
296 tcp_set_state(sk
, TCP_CLOSE
);
299 inet
->inet_dport
= 0;
300 sk
->sk_route_caps
= 0;
304 static void tcp_v6_mtu_reduced(struct sock
*sk
)
306 struct dst_entry
*dst
;
308 if ((1 << sk
->sk_state
) & (TCPF_LISTEN
| TCPF_CLOSE
))
311 dst
= inet6_csk_update_pmtu(sk
, tcp_sk(sk
)->mtu_info
);
315 if (inet_csk(sk
)->icsk_pmtu_cookie
> dst_mtu(dst
)) {
316 tcp_sync_mss(sk
, dst_mtu(dst
));
317 tcp_simple_retransmit(sk
);
321 static void tcp_v6_err(struct sk_buff
*skb
, struct inet6_skb_parm
*opt
,
322 u8 type
, u8 code
, int offset
, __be32 info
)
324 const struct ipv6hdr
*hdr
= (const struct ipv6hdr
*)skb
->data
;
325 const struct tcphdr
*th
= (struct tcphdr
*)(skb
->data
+offset
);
326 struct net
*net
= dev_net(skb
->dev
);
327 struct request_sock
*fastopen
;
328 struct ipv6_pinfo
*np
;
335 sk
= __inet6_lookup_established(net
, &tcp_hashinfo
,
336 &hdr
->daddr
, th
->dest
,
337 &hdr
->saddr
, ntohs(th
->source
),
341 __ICMP6_INC_STATS(net
, __in6_dev_get(skb
->dev
),
346 if (sk
->sk_state
== TCP_TIME_WAIT
) {
347 inet_twsk_put(inet_twsk(sk
));
350 seq
= ntohl(th
->seq
);
351 fatal
= icmpv6_err_convert(type
, code
, &err
);
352 if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
353 return tcp_req_err(sk
, seq
, fatal
);
356 if (sock_owned_by_user(sk
) && type
!= ICMPV6_PKT_TOOBIG
)
357 __NET_INC_STATS(net
, LINUX_MIB_LOCKDROPPEDICMPS
);
359 if (sk
->sk_state
== TCP_CLOSE
)
362 if (ipv6_hdr(skb
)->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
363 __NET_INC_STATS(net
, LINUX_MIB_TCPMINTTLDROP
);
368 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
369 fastopen
= tp
->fastopen_rsk
;
370 snd_una
= fastopen
? tcp_rsk(fastopen
)->snt_isn
: tp
->snd_una
;
371 if (sk
->sk_state
!= TCP_LISTEN
&&
372 !between(seq
, snd_una
, tp
->snd_nxt
)) {
373 __NET_INC_STATS(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
379 if (type
== NDISC_REDIRECT
) {
380 struct dst_entry
*dst
= __sk_dst_check(sk
, np
->dst_cookie
);
383 dst
->ops
->redirect(dst
, sk
, skb
);
387 if (type
== ICMPV6_PKT_TOOBIG
) {
388 /* We are not interested in TCP_LISTEN and open_requests
389 * (SYN-ACKs send out by Linux are always <576bytes so
390 * they should go through unfragmented).
392 if (sk
->sk_state
== TCP_LISTEN
)
395 if (!ip6_sk_accept_pmtu(sk
))
398 tp
->mtu_info
= ntohl(info
);
399 if (!sock_owned_by_user(sk
))
400 tcp_v6_mtu_reduced(sk
);
401 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED
,
408 /* Might be for an request_sock */
409 switch (sk
->sk_state
) {
412 /* Only in fast or simultaneous open. If a fast open socket is
413 * is already accepted it is treated as a connected one below.
415 if (fastopen
&& !fastopen
->sk
)
418 if (!sock_owned_by_user(sk
)) {
420 sk
->sk_error_report(sk
); /* Wake people up to see the error (see connect in sock.c) */
424 sk
->sk_err_soft
= err
;
428 if (!sock_owned_by_user(sk
) && np
->recverr
) {
430 sk
->sk_error_report(sk
);
432 sk
->sk_err_soft
= err
;
440 static int tcp_v6_send_synack(const struct sock
*sk
, struct dst_entry
*dst
,
442 struct request_sock
*req
,
443 struct tcp_fastopen_cookie
*foc
,
444 enum tcp_synack_type synack_type
)
446 struct inet_request_sock
*ireq
= inet_rsk(req
);
447 struct ipv6_pinfo
*np
= inet6_sk(sk
);
448 struct ipv6_txoptions
*opt
;
449 struct flowi6
*fl6
= &fl
->u
.ip6
;
453 /* First, grab a route. */
454 if (!dst
&& (dst
= inet6_csk_route_req(sk
, fl6
, req
,
455 IPPROTO_TCP
)) == NULL
)
458 skb
= tcp_make_synack(sk
, dst
, req
, foc
, synack_type
);
461 __tcp_v6_send_check(skb
, &ireq
->ir_v6_loc_addr
,
462 &ireq
->ir_v6_rmt_addr
);
464 fl6
->daddr
= ireq
->ir_v6_rmt_addr
;
465 if (np
->repflow
&& ireq
->pktopts
)
466 fl6
->flowlabel
= ip6_flowlabel(ipv6_hdr(ireq
->pktopts
));
469 opt
= ireq
->ipv6_opt
;
471 opt
= rcu_dereference(np
->opt
);
472 err
= ip6_xmit(sk
, skb
, fl6
, opt
, np
->tclass
);
474 err
= net_xmit_eval(err
);
482 static void tcp_v6_reqsk_destructor(struct request_sock
*req
)
484 kfree(inet_rsk(req
)->ipv6_opt
);
485 kfree_skb(inet_rsk(req
)->pktopts
);
488 #ifdef CONFIG_TCP_MD5SIG
489 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(const struct sock
*sk
,
490 const struct in6_addr
*addr
)
492 return tcp_md5_do_lookup(sk
, (union tcp_md5_addr
*)addr
, AF_INET6
);
495 static struct tcp_md5sig_key
*tcp_v6_md5_lookup(const struct sock
*sk
,
496 const struct sock
*addr_sk
)
498 return tcp_v6_md5_do_lookup(sk
, &addr_sk
->sk_v6_daddr
);
501 static int tcp_v6_parse_md5_keys(struct sock
*sk
, char __user
*optval
,
504 struct tcp_md5sig cmd
;
505 struct sockaddr_in6
*sin6
= (struct sockaddr_in6
*)&cmd
.tcpm_addr
;
507 if (optlen
< sizeof(cmd
))
510 if (copy_from_user(&cmd
, optval
, sizeof(cmd
)))
513 if (sin6
->sin6_family
!= AF_INET6
)
516 if (!cmd
.tcpm_keylen
) {
517 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
518 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
520 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
524 if (cmd
.tcpm_keylen
> TCP_MD5SIG_MAXKEYLEN
)
527 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
528 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
529 AF_INET
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
531 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
532 AF_INET6
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
535 static int tcp_v6_md5_hash_headers(struct tcp_md5sig_pool
*hp
,
536 const struct in6_addr
*daddr
,
537 const struct in6_addr
*saddr
,
538 const struct tcphdr
*th
, int nbytes
)
540 struct tcp6_pseudohdr
*bp
;
541 struct scatterlist sg
;
545 /* 1. TCP pseudo-header (RFC2460) */
548 bp
->protocol
= cpu_to_be32(IPPROTO_TCP
);
549 bp
->len
= cpu_to_be32(nbytes
);
551 _th
= (struct tcphdr
*)(bp
+ 1);
552 memcpy(_th
, th
, sizeof(*th
));
555 sg_init_one(&sg
, bp
, sizeof(*bp
) + sizeof(*th
));
556 ahash_request_set_crypt(hp
->md5_req
, &sg
, NULL
,
557 sizeof(*bp
) + sizeof(*th
));
558 return crypto_ahash_update(hp
->md5_req
);
561 static int tcp_v6_md5_hash_hdr(char *md5_hash
, const struct tcp_md5sig_key
*key
,
562 const struct in6_addr
*daddr
, struct in6_addr
*saddr
,
563 const struct tcphdr
*th
)
565 struct tcp_md5sig_pool
*hp
;
566 struct ahash_request
*req
;
568 hp
= tcp_get_md5sig_pool();
570 goto clear_hash_noput
;
573 if (crypto_ahash_init(req
))
575 if (tcp_v6_md5_hash_headers(hp
, daddr
, saddr
, th
, th
->doff
<< 2))
577 if (tcp_md5_hash_key(hp
, key
))
579 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
580 if (crypto_ahash_final(req
))
583 tcp_put_md5sig_pool();
587 tcp_put_md5sig_pool();
589 memset(md5_hash
, 0, 16);
593 static int tcp_v6_md5_hash_skb(char *md5_hash
,
594 const struct tcp_md5sig_key
*key
,
595 const struct sock
*sk
,
596 const struct sk_buff
*skb
)
598 const struct in6_addr
*saddr
, *daddr
;
599 struct tcp_md5sig_pool
*hp
;
600 struct ahash_request
*req
;
601 const struct tcphdr
*th
= tcp_hdr(skb
);
603 if (sk
) { /* valid for establish/request sockets */
604 saddr
= &sk
->sk_v6_rcv_saddr
;
605 daddr
= &sk
->sk_v6_daddr
;
607 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
608 saddr
= &ip6h
->saddr
;
609 daddr
= &ip6h
->daddr
;
612 hp
= tcp_get_md5sig_pool();
614 goto clear_hash_noput
;
617 if (crypto_ahash_init(req
))
620 if (tcp_v6_md5_hash_headers(hp
, daddr
, saddr
, th
, skb
->len
))
622 if (tcp_md5_hash_skb_data(hp
, skb
, th
->doff
<< 2))
624 if (tcp_md5_hash_key(hp
, key
))
626 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
627 if (crypto_ahash_final(req
))
630 tcp_put_md5sig_pool();
634 tcp_put_md5sig_pool();
636 memset(md5_hash
, 0, 16);
642 static bool tcp_v6_inbound_md5_hash(const struct sock
*sk
,
643 const struct sk_buff
*skb
)
645 #ifdef CONFIG_TCP_MD5SIG
646 const __u8
*hash_location
= NULL
;
647 struct tcp_md5sig_key
*hash_expected
;
648 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
649 const struct tcphdr
*th
= tcp_hdr(skb
);
653 hash_expected
= tcp_v6_md5_do_lookup(sk
, &ip6h
->saddr
);
654 hash_location
= tcp_parse_md5sig_option(th
);
656 /* We've parsed the options - do we have a hash? */
657 if (!hash_expected
&& !hash_location
)
660 if (hash_expected
&& !hash_location
) {
661 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5NOTFOUND
);
665 if (!hash_expected
&& hash_location
) {
666 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5UNEXPECTED
);
670 /* check the signature */
671 genhash
= tcp_v6_md5_hash_skb(newhash
,
675 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0) {
676 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5FAILURE
);
677 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
678 genhash
? "failed" : "mismatch",
679 &ip6h
->saddr
, ntohs(th
->source
),
680 &ip6h
->daddr
, ntohs(th
->dest
));
687 static void tcp_v6_init_req(struct request_sock
*req
,
688 const struct sock
*sk_listener
,
691 struct inet_request_sock
*ireq
= inet_rsk(req
);
692 const struct ipv6_pinfo
*np
= inet6_sk(sk_listener
);
694 ireq
->ir_v6_rmt_addr
= ipv6_hdr(skb
)->saddr
;
695 ireq
->ir_v6_loc_addr
= ipv6_hdr(skb
)->daddr
;
697 /* So that link locals have meaning */
698 if (!sk_listener
->sk_bound_dev_if
&&
699 ipv6_addr_type(&ireq
->ir_v6_rmt_addr
) & IPV6_ADDR_LINKLOCAL
)
700 ireq
->ir_iif
= tcp_v6_iif(skb
);
702 if (!TCP_SKB_CB(skb
)->tcp_tw_isn
&&
703 (ipv6_opt_accepted(sk_listener
, skb
, &TCP_SKB_CB(skb
)->header
.h6
) ||
704 np
->rxopt
.bits
.rxinfo
||
705 np
->rxopt
.bits
.rxoinfo
|| np
->rxopt
.bits
.rxhlim
||
706 np
->rxopt
.bits
.rxohlim
|| np
->repflow
)) {
707 atomic_inc(&skb
->users
);
712 static struct dst_entry
*tcp_v6_route_req(const struct sock
*sk
,
714 const struct request_sock
*req
,
719 return inet6_csk_route_req(sk
, &fl
->u
.ip6
, req
, IPPROTO_TCP
);
722 struct request_sock_ops tcp6_request_sock_ops __read_mostly
= {
724 .obj_size
= sizeof(struct tcp6_request_sock
),
725 .rtx_syn_ack
= tcp_rtx_synack
,
726 .send_ack
= tcp_v6_reqsk_send_ack
,
727 .destructor
= tcp_v6_reqsk_destructor
,
728 .send_reset
= tcp_v6_send_reset
,
729 .syn_ack_timeout
= tcp_syn_ack_timeout
,
732 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops
= {
733 .mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) -
734 sizeof(struct ipv6hdr
),
735 #ifdef CONFIG_TCP_MD5SIG
736 .req_md5_lookup
= tcp_v6_md5_lookup
,
737 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
739 .init_req
= tcp_v6_init_req
,
740 #ifdef CONFIG_SYN_COOKIES
741 .cookie_init_seq
= cookie_v6_init_sequence
,
743 .route_req
= tcp_v6_route_req
,
744 .init_seq
= tcp_v6_init_sequence
,
745 .send_synack
= tcp_v6_send_synack
,
748 static void tcp_v6_send_response(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
749 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
,
750 int oif
, struct tcp_md5sig_key
*key
, int rst
,
751 u8 tclass
, __be32 label
)
753 const struct tcphdr
*th
= tcp_hdr(skb
);
755 struct sk_buff
*buff
;
757 struct net
*net
= sk
? sock_net(sk
) : dev_net(skb_dst(skb
)->dev
);
758 struct sock
*ctl_sk
= net
->ipv6
.tcp_sk
;
759 unsigned int tot_len
= sizeof(struct tcphdr
);
760 struct dst_entry
*dst
;
764 tot_len
+= TCPOLEN_TSTAMP_ALIGNED
;
765 #ifdef CONFIG_TCP_MD5SIG
767 tot_len
+= TCPOLEN_MD5SIG_ALIGNED
;
770 buff
= alloc_skb(MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
,
775 skb_reserve(buff
, MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
);
777 t1
= (struct tcphdr
*) skb_push(buff
, tot_len
);
778 skb_reset_transport_header(buff
);
780 /* Swap the send and the receive. */
781 memset(t1
, 0, sizeof(*t1
));
782 t1
->dest
= th
->source
;
783 t1
->source
= th
->dest
;
784 t1
->doff
= tot_len
/ 4;
785 t1
->seq
= htonl(seq
);
786 t1
->ack_seq
= htonl(ack
);
787 t1
->ack
= !rst
|| !th
->ack
;
789 t1
->window
= htons(win
);
791 topt
= (__be32
*)(t1
+ 1);
794 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
795 (TCPOPT_TIMESTAMP
<< 8) | TCPOLEN_TIMESTAMP
);
796 *topt
++ = htonl(tsval
);
797 *topt
++ = htonl(tsecr
);
800 #ifdef CONFIG_TCP_MD5SIG
802 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
803 (TCPOPT_MD5SIG
<< 8) | TCPOLEN_MD5SIG
);
804 tcp_v6_md5_hash_hdr((__u8
*)topt
, key
,
805 &ipv6_hdr(skb
)->saddr
,
806 &ipv6_hdr(skb
)->daddr
, t1
);
810 memset(&fl6
, 0, sizeof(fl6
));
811 fl6
.daddr
= ipv6_hdr(skb
)->saddr
;
812 fl6
.saddr
= ipv6_hdr(skb
)->daddr
;
813 fl6
.flowlabel
= label
;
815 buff
->ip_summed
= CHECKSUM_PARTIAL
;
818 __tcp_v6_send_check(buff
, &fl6
.saddr
, &fl6
.daddr
);
820 fl6
.flowi6_proto
= IPPROTO_TCP
;
821 if (rt6_need_strict(&fl6
.daddr
) && !oif
)
822 fl6
.flowi6_oif
= tcp_v6_iif(skb
);
824 if (!oif
&& netif_index_is_l3_master(net
, skb
->skb_iif
))
827 fl6
.flowi6_oif
= oif
;
830 fl6
.flowi6_mark
= IP6_REPLY_MARK(net
, skb
->mark
);
831 fl6
.fl6_dport
= t1
->dest
;
832 fl6
.fl6_sport
= t1
->source
;
833 fl6
.flowi6_uid
= sock_net_uid(net
, sk
&& sk_fullsock(sk
) ? sk
: NULL
);
834 security_skb_classify_flow(skb
, flowi6_to_flowi(&fl6
));
836 /* Pass a socket to ip6_dst_lookup either it is for RST
837 * Underlying function will use this to retrieve the network
840 dst
= ip6_dst_lookup_flow(ctl_sk
, &fl6
, NULL
);
842 skb_dst_set(buff
, dst
);
843 ip6_xmit(ctl_sk
, buff
, &fl6
, NULL
, tclass
);
844 TCP_INC_STATS(net
, TCP_MIB_OUTSEGS
);
846 TCP_INC_STATS(net
, TCP_MIB_OUTRSTS
);
853 static void tcp_v6_send_reset(const struct sock
*sk
, struct sk_buff
*skb
)
855 const struct tcphdr
*th
= tcp_hdr(skb
);
856 u32 seq
= 0, ack_seq
= 0;
857 struct tcp_md5sig_key
*key
= NULL
;
858 #ifdef CONFIG_TCP_MD5SIG
859 const __u8
*hash_location
= NULL
;
860 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
861 unsigned char newhash
[16];
863 struct sock
*sk1
= NULL
;
870 /* If sk not NULL, it means we did a successful lookup and incoming
871 * route had to be correct. prequeue might have dropped our dst.
873 if (!sk
&& !ipv6_unicast_destination(skb
))
876 #ifdef CONFIG_TCP_MD5SIG
878 hash_location
= tcp_parse_md5sig_option(th
);
879 if (sk
&& sk_fullsock(sk
)) {
880 key
= tcp_v6_md5_do_lookup(sk
, &ipv6h
->saddr
);
881 } else if (hash_location
) {
883 * active side is lost. Try to find listening socket through
884 * source port, and then find md5 key through listening socket.
885 * we are not loose security here:
886 * Incoming packet is checked with md5 hash with finding key,
887 * no RST generated if md5 hash doesn't match.
889 sk1
= inet6_lookup_listener(dev_net(skb_dst(skb
)->dev
),
890 &tcp_hashinfo
, NULL
, 0,
892 th
->source
, &ipv6h
->daddr
,
893 ntohs(th
->source
), tcp_v6_iif(skb
));
897 key
= tcp_v6_md5_do_lookup(sk1
, &ipv6h
->saddr
);
901 genhash
= tcp_v6_md5_hash_skb(newhash
, key
, NULL
, skb
);
902 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0)
908 seq
= ntohl(th
->ack_seq
);
910 ack_seq
= ntohl(th
->seq
) + th
->syn
+ th
->fin
+ skb
->len
-
913 oif
= sk
? sk
->sk_bound_dev_if
: 0;
914 tcp_v6_send_response(sk
, skb
, seq
, ack_seq
, 0, 0, 0, oif
, key
, 1, 0, 0);
916 #ifdef CONFIG_TCP_MD5SIG
922 static void tcp_v6_send_ack(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
923 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
, int oif
,
924 struct tcp_md5sig_key
*key
, u8 tclass
,
927 tcp_v6_send_response(sk
, skb
, seq
, ack
, win
, tsval
, tsecr
, oif
, key
, 0,
931 static void tcp_v6_timewait_ack(struct sock
*sk
, struct sk_buff
*skb
)
933 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
934 struct tcp_timewait_sock
*tcptw
= tcp_twsk(sk
);
936 tcp_v6_send_ack(sk
, skb
, tcptw
->tw_snd_nxt
, tcptw
->tw_rcv_nxt
,
937 tcptw
->tw_rcv_wnd
>> tw
->tw_rcv_wscale
,
938 tcp_time_stamp
+ tcptw
->tw_ts_offset
,
939 tcptw
->tw_ts_recent
, tw
->tw_bound_dev_if
, tcp_twsk_md5_key(tcptw
),
940 tw
->tw_tclass
, cpu_to_be32(tw
->tw_flowlabel
));
945 static void tcp_v6_reqsk_send_ack(const struct sock
*sk
, struct sk_buff
*skb
,
946 struct request_sock
*req
)
948 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
949 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
952 * The window field (SEG.WND) of every outgoing segment, with the
953 * exception of <SYN> segments, MUST be right-shifted by
954 * Rcv.Wind.Shift bits:
956 tcp_v6_send_ack(sk
, skb
, (sk
->sk_state
== TCP_LISTEN
) ?
957 tcp_rsk(req
)->snt_isn
+ 1 : tcp_sk(sk
)->snd_nxt
,
958 tcp_rsk(req
)->rcv_nxt
,
959 req
->rsk_rcv_wnd
>> inet_rsk(req
)->rcv_wscale
,
960 tcp_time_stamp
+ tcp_rsk(req
)->ts_off
,
961 req
->ts_recent
, sk
->sk_bound_dev_if
,
962 tcp_v6_md5_do_lookup(sk
, &ipv6_hdr(skb
)->daddr
),
967 static struct sock
*tcp_v6_cookie_check(struct sock
*sk
, struct sk_buff
*skb
)
969 #ifdef CONFIG_SYN_COOKIES
970 const struct tcphdr
*th
= tcp_hdr(skb
);
973 sk
= cookie_v6_check(sk
, skb
);
978 static int tcp_v6_conn_request(struct sock
*sk
, struct sk_buff
*skb
)
980 if (skb
->protocol
== htons(ETH_P_IP
))
981 return tcp_v4_conn_request(sk
, skb
);
983 if (!ipv6_unicast_destination(skb
))
986 return tcp_conn_request(&tcp6_request_sock_ops
,
987 &tcp_request_sock_ipv6_ops
, sk
, skb
);
991 return 0; /* don't send reset */
994 static struct sock
*tcp_v6_syn_recv_sock(const struct sock
*sk
, struct sk_buff
*skb
,
995 struct request_sock
*req
,
996 struct dst_entry
*dst
,
997 struct request_sock
*req_unhash
,
1000 struct inet_request_sock
*ireq
;
1001 struct ipv6_pinfo
*newnp
;
1002 const struct ipv6_pinfo
*np
= inet6_sk(sk
);
1003 struct ipv6_txoptions
*opt
;
1004 struct tcp6_sock
*newtcp6sk
;
1005 struct inet_sock
*newinet
;
1006 struct tcp_sock
*newtp
;
1008 #ifdef CONFIG_TCP_MD5SIG
1009 struct tcp_md5sig_key
*key
;
1013 if (skb
->protocol
== htons(ETH_P_IP
)) {
1018 newsk
= tcp_v4_syn_recv_sock(sk
, skb
, req
, dst
,
1019 req_unhash
, own_req
);
1024 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1025 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1027 newinet
= inet_sk(newsk
);
1028 newnp
= inet6_sk(newsk
);
1029 newtp
= tcp_sk(newsk
);
1031 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1033 newnp
->saddr
= newsk
->sk_v6_rcv_saddr
;
1035 inet_csk(newsk
)->icsk_af_ops
= &ipv6_mapped
;
1036 newsk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
1037 #ifdef CONFIG_TCP_MD5SIG
1038 newtp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
1041 newnp
->ipv6_ac_list
= NULL
;
1042 newnp
->ipv6_fl_list
= NULL
;
1043 newnp
->pktoptions
= NULL
;
1045 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1046 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1047 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1049 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1052 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1053 * here, tcp_create_openreq_child now does this for us, see the comment in
1054 * that function for the gory details. -acme
1057 /* It is tricky place. Until this moment IPv4 tcp
1058 worked with IPv6 icsk.icsk_af_ops.
1061 tcp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
1066 ireq
= inet_rsk(req
);
1068 if (sk_acceptq_is_full(sk
))
1072 dst
= inet6_csk_route_req(sk
, &fl6
, req
, IPPROTO_TCP
);
1077 newsk
= tcp_create_openreq_child(sk
, req
, skb
);
1082 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1083 * count here, tcp_create_openreq_child now does this for us, see the
1084 * comment in that function for the gory details. -acme
1087 newsk
->sk_gso_type
= SKB_GSO_TCPV6
;
1088 ip6_dst_store(newsk
, dst
, NULL
, NULL
);
1089 inet6_sk_rx_dst_set(newsk
, skb
);
1091 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1092 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1094 newtp
= tcp_sk(newsk
);
1095 newinet
= inet_sk(newsk
);
1096 newnp
= inet6_sk(newsk
);
1098 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1100 newsk
->sk_v6_daddr
= ireq
->ir_v6_rmt_addr
;
1101 newnp
->saddr
= ireq
->ir_v6_loc_addr
;
1102 newsk
->sk_v6_rcv_saddr
= ireq
->ir_v6_loc_addr
;
1103 newsk
->sk_bound_dev_if
= ireq
->ir_iif
;
1105 /* Now IPv6 options...
1107 First: no IPv4 options.
1109 newinet
->inet_opt
= NULL
;
1110 newnp
->ipv6_ac_list
= NULL
;
1111 newnp
->ipv6_fl_list
= NULL
;
1114 newnp
->rxopt
.all
= np
->rxopt
.all
;
1116 newnp
->pktoptions
= NULL
;
1118 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1119 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1120 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1122 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1124 /* Clone native IPv6 options from listening socket (if any)
1126 Yes, keeping reference count would be much more clever,
1127 but we make one more one thing there: reattach optmem
1130 opt
= ireq
->ipv6_opt
;
1132 opt
= rcu_dereference(np
->opt
);
1134 opt
= ipv6_dup_options(newsk
, opt
);
1135 RCU_INIT_POINTER(newnp
->opt
, opt
);
1137 inet_csk(newsk
)->icsk_ext_hdr_len
= 0;
1139 inet_csk(newsk
)->icsk_ext_hdr_len
= opt
->opt_nflen
+
1142 tcp_ca_openreq_child(newsk
, dst
);
1144 tcp_sync_mss(newsk
, dst_mtu(dst
));
1145 newtp
->advmss
= dst_metric_advmss(dst
);
1146 if (tcp_sk(sk
)->rx_opt
.user_mss
&&
1147 tcp_sk(sk
)->rx_opt
.user_mss
< newtp
->advmss
)
1148 newtp
->advmss
= tcp_sk(sk
)->rx_opt
.user_mss
;
1150 tcp_initialize_rcv_mss(newsk
);
1152 newinet
->inet_daddr
= newinet
->inet_saddr
= LOOPBACK4_IPV6
;
1153 newinet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
1155 #ifdef CONFIG_TCP_MD5SIG
1156 /* Copy over the MD5 key from the original socket */
1157 key
= tcp_v6_md5_do_lookup(sk
, &newsk
->sk_v6_daddr
);
1159 /* We're using one, so create a matching key
1160 * on the newsk structure. If we fail to get
1161 * memory, then we end up not copying the key
1164 tcp_md5_do_add(newsk
, (union tcp_md5_addr
*)&newsk
->sk_v6_daddr
,
1165 AF_INET6
, key
->key
, key
->keylen
,
1166 sk_gfp_mask(sk
, GFP_ATOMIC
));
1170 if (__inet_inherit_port(sk
, newsk
) < 0) {
1171 inet_csk_prepare_forced_close(newsk
);
1175 *own_req
= inet_ehash_nolisten(newsk
, req_to_sk(req_unhash
));
1177 tcp_move_syn(newtp
, req
);
1179 /* Clone pktoptions received with SYN, if we own the req */
1180 if (ireq
->pktopts
) {
1181 newnp
->pktoptions
= skb_clone(ireq
->pktopts
,
1182 sk_gfp_mask(sk
, GFP_ATOMIC
));
1183 consume_skb(ireq
->pktopts
);
1184 ireq
->pktopts
= NULL
;
1185 if (newnp
->pktoptions
)
1186 skb_set_owner_r(newnp
->pktoptions
, newsk
);
1193 __NET_INC_STATS(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
1201 static void tcp_v6_restore_cb(struct sk_buff
*skb
)
1203 /* We need to move header back to the beginning if xfrm6_policy_check()
1204 * and tcp_v6_fill_cb() are going to be called again.
1205 * ip6_datagram_recv_specific_ctl() also expects IP6CB to be there.
1207 memmove(IP6CB(skb
), &TCP_SKB_CB(skb
)->header
.h6
,
1208 sizeof(struct inet6_skb_parm
));
1211 /* The socket must have it's spinlock held when we get
1212 * here, unless it is a TCP_LISTEN socket.
1214 * We have a potential double-lock case here, so even when
1215 * doing backlog processing we use the BH locking scheme.
1216 * This is because we cannot sleep with the original spinlock
1219 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
)
1221 struct ipv6_pinfo
*np
= inet6_sk(sk
);
1222 struct tcp_sock
*tp
;
1223 struct sk_buff
*opt_skb
= NULL
;
1225 /* Imagine: socket is IPv6. IPv4 packet arrives,
1226 goes to IPv4 receive handler and backlogged.
1227 From backlog it always goes here. Kerboom...
1228 Fortunately, tcp_rcv_established and rcv_established
1229 handle them correctly, but it is not case with
1230 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1233 if (skb
->protocol
== htons(ETH_P_IP
))
1234 return tcp_v4_do_rcv(sk
, skb
);
1236 if (tcp_filter(sk
, skb
))
1240 * socket locking is here for SMP purposes as backlog rcv
1241 * is currently called with bh processing disabled.
1244 /* Do Stevens' IPV6_PKTOPTIONS.
1246 Yes, guys, it is the only place in our code, where we
1247 may make it not affecting IPv4.
1248 The rest of code is protocol independent,
1249 and I do not like idea to uglify IPv4.
1251 Actually, all the idea behind IPV6_PKTOPTIONS
1252 looks not very well thought. For now we latch
1253 options, received in the last packet, enqueued
1254 by tcp. Feel free to propose better solution.
1258 opt_skb
= skb_clone(skb
, sk_gfp_mask(sk
, GFP_ATOMIC
));
1260 if (sk
->sk_state
== TCP_ESTABLISHED
) { /* Fast path */
1261 struct dst_entry
*dst
= sk
->sk_rx_dst
;
1263 sock_rps_save_rxhash(sk
, skb
);
1264 sk_mark_napi_id(sk
, skb
);
1266 if (inet_sk(sk
)->rx_dst_ifindex
!= skb
->skb_iif
||
1267 dst
->ops
->check(dst
, np
->rx_dst_cookie
) == NULL
) {
1269 sk
->sk_rx_dst
= NULL
;
1273 tcp_rcv_established(sk
, skb
, tcp_hdr(skb
), skb
->len
);
1275 goto ipv6_pktoptions
;
1279 if (tcp_checksum_complete(skb
))
1282 if (sk
->sk_state
== TCP_LISTEN
) {
1283 struct sock
*nsk
= tcp_v6_cookie_check(sk
, skb
);
1289 sock_rps_save_rxhash(nsk
, skb
);
1290 sk_mark_napi_id(nsk
, skb
);
1291 if (tcp_child_process(sk
, nsk
, skb
))
1294 __kfree_skb(opt_skb
);
1298 sock_rps_save_rxhash(sk
, skb
);
1300 if (tcp_rcv_state_process(sk
, skb
))
1303 goto ipv6_pktoptions
;
1307 tcp_v6_send_reset(sk
, skb
);
1310 __kfree_skb(opt_skb
);
1314 TCP_INC_STATS(sock_net(sk
), TCP_MIB_CSUMERRORS
);
1315 TCP_INC_STATS(sock_net(sk
), TCP_MIB_INERRS
);
1320 /* Do you ask, what is it?
1322 1. skb was enqueued by tcp.
1323 2. skb is added to tail of read queue, rather than out of order.
1324 3. socket is not in passive state.
1325 4. Finally, it really contains options, which user wants to receive.
1328 if (TCP_SKB_CB(opt_skb
)->end_seq
== tp
->rcv_nxt
&&
1329 !((1 << sk
->sk_state
) & (TCPF_CLOSE
| TCPF_LISTEN
))) {
1330 if (np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
)
1331 np
->mcast_oif
= tcp_v6_iif(opt_skb
);
1332 if (np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
)
1333 np
->mcast_hops
= ipv6_hdr(opt_skb
)->hop_limit
;
1334 if (np
->rxopt
.bits
.rxflow
|| np
->rxopt
.bits
.rxtclass
)
1335 np
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(opt_skb
));
1337 np
->flow_label
= ip6_flowlabel(ipv6_hdr(opt_skb
));
1338 if (ipv6_opt_accepted(sk
, opt_skb
, &TCP_SKB_CB(opt_skb
)->header
.h6
)) {
1339 skb_set_owner_r(opt_skb
, sk
);
1340 tcp_v6_restore_cb(opt_skb
);
1341 opt_skb
= xchg(&np
->pktoptions
, opt_skb
);
1343 __kfree_skb(opt_skb
);
1344 opt_skb
= xchg(&np
->pktoptions
, NULL
);
1352 static void tcp_v6_fill_cb(struct sk_buff
*skb
, const struct ipv6hdr
*hdr
,
1353 const struct tcphdr
*th
)
1355 /* This is tricky: we move IP6CB at its correct location into
1356 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because
1357 * _decode_session6() uses IP6CB().
1358 * barrier() makes sure compiler won't play aliasing games.
1360 memmove(&TCP_SKB_CB(skb
)->header
.h6
, IP6CB(skb
),
1361 sizeof(struct inet6_skb_parm
));
1364 TCP_SKB_CB(skb
)->seq
= ntohl(th
->seq
);
1365 TCP_SKB_CB(skb
)->end_seq
= (TCP_SKB_CB(skb
)->seq
+ th
->syn
+ th
->fin
+
1366 skb
->len
- th
->doff
*4);
1367 TCP_SKB_CB(skb
)->ack_seq
= ntohl(th
->ack_seq
);
1368 TCP_SKB_CB(skb
)->tcp_flags
= tcp_flag_byte(th
);
1369 TCP_SKB_CB(skb
)->tcp_tw_isn
= 0;
1370 TCP_SKB_CB(skb
)->ip_dsfield
= ipv6_get_dsfield(hdr
);
1371 TCP_SKB_CB(skb
)->sacked
= 0;
1374 static int tcp_v6_rcv(struct sk_buff
*skb
)
1376 const struct tcphdr
*th
;
1377 const struct ipv6hdr
*hdr
;
1381 struct net
*net
= dev_net(skb
->dev
);
1383 if (skb
->pkt_type
!= PACKET_HOST
)
1387 * Count it even if it's bad.
1389 __TCP_INC_STATS(net
, TCP_MIB_INSEGS
);
1391 if (!pskb_may_pull(skb
, sizeof(struct tcphdr
)))
1394 th
= (const struct tcphdr
*)skb
->data
;
1396 if (unlikely(th
->doff
< sizeof(struct tcphdr
)/4))
1398 if (!pskb_may_pull(skb
, th
->doff
*4))
1401 if (skb_checksum_init(skb
, IPPROTO_TCP
, ip6_compute_pseudo
))
1404 th
= (const struct tcphdr
*)skb
->data
;
1405 hdr
= ipv6_hdr(skb
);
1408 sk
= __inet6_lookup_skb(&tcp_hashinfo
, skb
, __tcp_hdrlen(th
),
1409 th
->source
, th
->dest
, inet6_iif(skb
),
1415 if (sk
->sk_state
== TCP_TIME_WAIT
)
1418 if (sk
->sk_state
== TCP_NEW_SYN_RECV
) {
1419 struct request_sock
*req
= inet_reqsk(sk
);
1422 sk
= req
->rsk_listener
;
1423 tcp_v6_fill_cb(skb
, hdr
, th
);
1424 if (tcp_v6_inbound_md5_hash(sk
, skb
)) {
1425 sk_drops_add(sk
, skb
);
1429 if (unlikely(sk
->sk_state
!= TCP_LISTEN
)) {
1430 inet_csk_reqsk_queue_drop_and_put(sk
, req
);
1435 nsk
= tcp_check_req(sk
, skb
, req
, false);
1438 goto discard_and_relse
;
1442 tcp_v6_restore_cb(skb
);
1443 } else if (tcp_child_process(sk
, nsk
, skb
)) {
1444 tcp_v6_send_reset(nsk
, skb
);
1445 goto discard_and_relse
;
1451 if (hdr
->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
1452 __NET_INC_STATS(net
, LINUX_MIB_TCPMINTTLDROP
);
1453 goto discard_and_relse
;
1456 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
1457 goto discard_and_relse
;
1459 tcp_v6_fill_cb(skb
, hdr
, th
);
1461 if (tcp_v6_inbound_md5_hash(sk
, skb
))
1462 goto discard_and_relse
;
1464 if (tcp_filter(sk
, skb
))
1465 goto discard_and_relse
;
1466 th
= (const struct tcphdr
*)skb
->data
;
1467 hdr
= ipv6_hdr(skb
);
1471 if (sk
->sk_state
== TCP_LISTEN
) {
1472 ret
= tcp_v6_do_rcv(sk
, skb
);
1473 goto put_and_return
;
1476 sk_incoming_cpu_update(sk
);
1478 bh_lock_sock_nested(sk
);
1479 tcp_segs_in(tcp_sk(sk
), skb
);
1481 if (!sock_owned_by_user(sk
)) {
1482 if (!tcp_prequeue(sk
, skb
))
1483 ret
= tcp_v6_do_rcv(sk
, skb
);
1484 } else if (tcp_add_backlog(sk
, skb
)) {
1485 goto discard_and_relse
;
1492 return ret
? -1 : 0;
1495 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
1498 tcp_v6_fill_cb(skb
, hdr
, th
);
1500 if (tcp_checksum_complete(skb
)) {
1502 __TCP_INC_STATS(net
, TCP_MIB_CSUMERRORS
);
1504 __TCP_INC_STATS(net
, TCP_MIB_INERRS
);
1506 tcp_v6_send_reset(NULL
, skb
);
1514 sk_drops_add(sk
, skb
);
1520 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
)) {
1521 inet_twsk_put(inet_twsk(sk
));
1525 tcp_v6_fill_cb(skb
, hdr
, th
);
1527 if (tcp_checksum_complete(skb
)) {
1528 inet_twsk_put(inet_twsk(sk
));
1532 switch (tcp_timewait_state_process(inet_twsk(sk
), skb
, th
)) {
1537 sk2
= inet6_lookup_listener(dev_net(skb
->dev
), &tcp_hashinfo
,
1538 skb
, __tcp_hdrlen(th
),
1539 &ipv6_hdr(skb
)->saddr
, th
->source
,
1540 &ipv6_hdr(skb
)->daddr
,
1541 ntohs(th
->dest
), tcp_v6_iif(skb
));
1543 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
1544 inet_twsk_deschedule_put(tw
);
1546 tcp_v6_restore_cb(skb
);
1550 /* Fall through to ACK */
1553 tcp_v6_timewait_ack(sk
, skb
);
1556 tcp_v6_restore_cb(skb
);
1557 tcp_v6_send_reset(sk
, skb
);
1558 inet_twsk_deschedule_put(inet_twsk(sk
));
1560 case TCP_TW_SUCCESS
:
1566 static void tcp_v6_early_demux(struct sk_buff
*skb
)
1568 const struct ipv6hdr
*hdr
;
1569 const struct tcphdr
*th
;
1572 if (skb
->pkt_type
!= PACKET_HOST
)
1575 if (!pskb_may_pull(skb
, skb_transport_offset(skb
) + sizeof(struct tcphdr
)))
1578 hdr
= ipv6_hdr(skb
);
1581 if (th
->doff
< sizeof(struct tcphdr
) / 4)
1584 /* Note : We use inet6_iif() here, not tcp_v6_iif() */
1585 sk
= __inet6_lookup_established(dev_net(skb
->dev
), &tcp_hashinfo
,
1586 &hdr
->saddr
, th
->source
,
1587 &hdr
->daddr
, ntohs(th
->dest
),
1591 skb
->destructor
= sock_edemux
;
1592 if (sk_fullsock(sk
)) {
1593 struct dst_entry
*dst
= READ_ONCE(sk
->sk_rx_dst
);
1596 dst
= dst_check(dst
, inet6_sk(sk
)->rx_dst_cookie
);
1598 inet_sk(sk
)->rx_dst_ifindex
== skb
->skb_iif
)
1599 skb_dst_set_noref(skb
, dst
);
1604 static struct timewait_sock_ops tcp6_timewait_sock_ops
= {
1605 .twsk_obj_size
= sizeof(struct tcp6_timewait_sock
),
1606 .twsk_unique
= tcp_twsk_unique
,
1607 .twsk_destructor
= tcp_twsk_destructor
,
1610 static const struct inet_connection_sock_af_ops ipv6_specific
= {
1611 .queue_xmit
= inet6_csk_xmit
,
1612 .send_check
= tcp_v6_send_check
,
1613 .rebuild_header
= inet6_sk_rebuild_header
,
1614 .sk_rx_dst_set
= inet6_sk_rx_dst_set
,
1615 .conn_request
= tcp_v6_conn_request
,
1616 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1617 .net_header_len
= sizeof(struct ipv6hdr
),
1618 .net_frag_header_len
= sizeof(struct frag_hdr
),
1619 .setsockopt
= ipv6_setsockopt
,
1620 .getsockopt
= ipv6_getsockopt
,
1621 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1622 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1623 .bind_conflict
= inet6_csk_bind_conflict
,
1624 #ifdef CONFIG_COMPAT
1625 .compat_setsockopt
= compat_ipv6_setsockopt
,
1626 .compat_getsockopt
= compat_ipv6_getsockopt
,
1628 .mtu_reduced
= tcp_v6_mtu_reduced
,
1631 #ifdef CONFIG_TCP_MD5SIG
1632 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
= {
1633 .md5_lookup
= tcp_v6_md5_lookup
,
1634 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
1635 .md5_parse
= tcp_v6_parse_md5_keys
,
1640 * TCP over IPv4 via INET6 API
1642 static const struct inet_connection_sock_af_ops ipv6_mapped
= {
1643 .queue_xmit
= ip_queue_xmit
,
1644 .send_check
= tcp_v4_send_check
,
1645 .rebuild_header
= inet_sk_rebuild_header
,
1646 .sk_rx_dst_set
= inet_sk_rx_dst_set
,
1647 .conn_request
= tcp_v6_conn_request
,
1648 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1649 .net_header_len
= sizeof(struct iphdr
),
1650 .setsockopt
= ipv6_setsockopt
,
1651 .getsockopt
= ipv6_getsockopt
,
1652 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1653 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1654 .bind_conflict
= inet6_csk_bind_conflict
,
1655 #ifdef CONFIG_COMPAT
1656 .compat_setsockopt
= compat_ipv6_setsockopt
,
1657 .compat_getsockopt
= compat_ipv6_getsockopt
,
1659 .mtu_reduced
= tcp_v4_mtu_reduced
,
1662 #ifdef CONFIG_TCP_MD5SIG
1663 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
= {
1664 .md5_lookup
= tcp_v4_md5_lookup
,
1665 .calc_md5_hash
= tcp_v4_md5_hash_skb
,
1666 .md5_parse
= tcp_v6_parse_md5_keys
,
1670 /* NOTE: A lot of things set to zero explicitly by call to
1671 * sk_alloc() so need not be done here.
1673 static int tcp_v6_init_sock(struct sock
*sk
)
1675 struct inet_connection_sock
*icsk
= inet_csk(sk
);
1679 icsk
->icsk_af_ops
= &ipv6_specific
;
1681 #ifdef CONFIG_TCP_MD5SIG
1682 tcp_sk(sk
)->af_specific
= &tcp_sock_ipv6_specific
;
1688 static void tcp_v6_destroy_sock(struct sock
*sk
)
1690 tcp_v4_destroy_sock(sk
);
1691 inet6_destroy_sock(sk
);
1694 #ifdef CONFIG_PROC_FS
1695 /* Proc filesystem TCPv6 sock list dumping. */
1696 static void get_openreq6(struct seq_file
*seq
,
1697 const struct request_sock
*req
, int i
)
1699 long ttd
= req
->rsk_timer
.expires
- jiffies
;
1700 const struct in6_addr
*src
= &inet_rsk(req
)->ir_v6_loc_addr
;
1701 const struct in6_addr
*dest
= &inet_rsk(req
)->ir_v6_rmt_addr
;
1707 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1708 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n",
1710 src
->s6_addr32
[0], src
->s6_addr32
[1],
1711 src
->s6_addr32
[2], src
->s6_addr32
[3],
1712 inet_rsk(req
)->ir_num
,
1713 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1714 dest
->s6_addr32
[2], dest
->s6_addr32
[3],
1715 ntohs(inet_rsk(req
)->ir_rmt_port
),
1717 0, 0, /* could print option size, but that is af dependent. */
1718 1, /* timers active (only the expire timer) */
1719 jiffies_to_clock_t(ttd
),
1721 from_kuid_munged(seq_user_ns(seq
),
1722 sock_i_uid(req
->rsk_listener
)),
1723 0, /* non standard timer */
1724 0, /* open_requests have no inode */
1728 static void get_tcp6_sock(struct seq_file
*seq
, struct sock
*sp
, int i
)
1730 const struct in6_addr
*dest
, *src
;
1733 unsigned long timer_expires
;
1734 const struct inet_sock
*inet
= inet_sk(sp
);
1735 const struct tcp_sock
*tp
= tcp_sk(sp
);
1736 const struct inet_connection_sock
*icsk
= inet_csk(sp
);
1737 const struct fastopen_queue
*fastopenq
= &icsk
->icsk_accept_queue
.fastopenq
;
1741 dest
= &sp
->sk_v6_daddr
;
1742 src
= &sp
->sk_v6_rcv_saddr
;
1743 destp
= ntohs(inet
->inet_dport
);
1744 srcp
= ntohs(inet
->inet_sport
);
1746 if (icsk
->icsk_pending
== ICSK_TIME_RETRANS
||
1747 icsk
->icsk_pending
== ICSK_TIME_EARLY_RETRANS
||
1748 icsk
->icsk_pending
== ICSK_TIME_LOSS_PROBE
) {
1750 timer_expires
= icsk
->icsk_timeout
;
1751 } else if (icsk
->icsk_pending
== ICSK_TIME_PROBE0
) {
1753 timer_expires
= icsk
->icsk_timeout
;
1754 } else if (timer_pending(&sp
->sk_timer
)) {
1756 timer_expires
= sp
->sk_timer
.expires
;
1759 timer_expires
= jiffies
;
1762 state
= sk_state_load(sp
);
1763 if (state
== TCP_LISTEN
)
1764 rx_queue
= sp
->sk_ack_backlog
;
1766 /* Because we don't lock the socket,
1767 * we might find a transient negative value.
1769 rx_queue
= max_t(int, tp
->rcv_nxt
- tp
->copied_seq
, 0);
1772 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1773 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
1775 src
->s6_addr32
[0], src
->s6_addr32
[1],
1776 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1777 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1778 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1780 tp
->write_seq
- tp
->snd_una
,
1783 jiffies_delta_to_clock_t(timer_expires
- jiffies
),
1784 icsk
->icsk_retransmits
,
1785 from_kuid_munged(seq_user_ns(seq
), sock_i_uid(sp
)),
1786 icsk
->icsk_probes_out
,
1788 atomic_read(&sp
->sk_refcnt
), sp
,
1789 jiffies_to_clock_t(icsk
->icsk_rto
),
1790 jiffies_to_clock_t(icsk
->icsk_ack
.ato
),
1791 (icsk
->icsk_ack
.quick
<< 1) | icsk
->icsk_ack
.pingpong
,
1793 state
== TCP_LISTEN
?
1794 fastopenq
->max_qlen
:
1795 (tcp_in_initial_slowstart(tp
) ? -1 : tp
->snd_ssthresh
)
1799 static void get_timewait6_sock(struct seq_file
*seq
,
1800 struct inet_timewait_sock
*tw
, int i
)
1802 long delta
= tw
->tw_timer
.expires
- jiffies
;
1803 const struct in6_addr
*dest
, *src
;
1806 dest
= &tw
->tw_v6_daddr
;
1807 src
= &tw
->tw_v6_rcv_saddr
;
1808 destp
= ntohs(tw
->tw_dport
);
1809 srcp
= ntohs(tw
->tw_sport
);
1812 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1813 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
1815 src
->s6_addr32
[0], src
->s6_addr32
[1],
1816 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1817 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1818 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1819 tw
->tw_substate
, 0, 0,
1820 3, jiffies_delta_to_clock_t(delta
), 0, 0, 0, 0,
1821 atomic_read(&tw
->tw_refcnt
), tw
);
1824 static int tcp6_seq_show(struct seq_file
*seq
, void *v
)
1826 struct tcp_iter_state
*st
;
1827 struct sock
*sk
= v
;
1829 if (v
== SEQ_START_TOKEN
) {
1834 "st tx_queue rx_queue tr tm->when retrnsmt"
1835 " uid timeout inode\n");
1840 if (sk
->sk_state
== TCP_TIME_WAIT
)
1841 get_timewait6_sock(seq
, v
, st
->num
);
1842 else if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
1843 get_openreq6(seq
, v
, st
->num
);
1845 get_tcp6_sock(seq
, v
, st
->num
);
1850 static const struct file_operations tcp6_afinfo_seq_fops
= {
1851 .owner
= THIS_MODULE
,
1852 .open
= tcp_seq_open
,
1854 .llseek
= seq_lseek
,
1855 .release
= seq_release_net
1858 static struct tcp_seq_afinfo tcp6_seq_afinfo
= {
1861 .seq_fops
= &tcp6_afinfo_seq_fops
,
1863 .show
= tcp6_seq_show
,
1867 int __net_init
tcp6_proc_init(struct net
*net
)
1869 return tcp_proc_register(net
, &tcp6_seq_afinfo
);
1872 void tcp6_proc_exit(struct net
*net
)
1874 tcp_proc_unregister(net
, &tcp6_seq_afinfo
);
1878 struct proto tcpv6_prot
= {
1880 .owner
= THIS_MODULE
,
1882 .connect
= tcp_v6_connect
,
1883 .disconnect
= tcp_disconnect
,
1884 .accept
= inet_csk_accept
,
1886 .init
= tcp_v6_init_sock
,
1887 .destroy
= tcp_v6_destroy_sock
,
1888 .shutdown
= tcp_shutdown
,
1889 .setsockopt
= tcp_setsockopt
,
1890 .getsockopt
= tcp_getsockopt
,
1891 .recvmsg
= tcp_recvmsg
,
1892 .sendmsg
= tcp_sendmsg
,
1893 .sendpage
= tcp_sendpage
,
1894 .backlog_rcv
= tcp_v6_do_rcv
,
1895 .release_cb
= tcp_release_cb
,
1897 .unhash
= inet_unhash
,
1898 .get_port
= inet_csk_get_port
,
1899 .enter_memory_pressure
= tcp_enter_memory_pressure
,
1900 .stream_memory_free
= tcp_stream_memory_free
,
1901 .sockets_allocated
= &tcp_sockets_allocated
,
1902 .memory_allocated
= &tcp_memory_allocated
,
1903 .memory_pressure
= &tcp_memory_pressure
,
1904 .orphan_count
= &tcp_orphan_count
,
1905 .sysctl_mem
= sysctl_tcp_mem
,
1906 .sysctl_wmem
= sysctl_tcp_wmem
,
1907 .sysctl_rmem
= sysctl_tcp_rmem
,
1908 .max_header
= MAX_TCP_HEADER
,
1909 .obj_size
= sizeof(struct tcp6_sock
),
1910 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1911 .twsk_prot
= &tcp6_timewait_sock_ops
,
1912 .rsk_prot
= &tcp6_request_sock_ops
,
1913 .h
.hashinfo
= &tcp_hashinfo
,
1914 .no_autobind
= true,
1915 #ifdef CONFIG_COMPAT
1916 .compat_setsockopt
= compat_tcp_setsockopt
,
1917 .compat_getsockopt
= compat_tcp_getsockopt
,
1919 .diag_destroy
= tcp_abort
,
1922 static const struct inet6_protocol tcpv6_protocol
= {
1923 .early_demux
= tcp_v6_early_demux
,
1924 .handler
= tcp_v6_rcv
,
1925 .err_handler
= tcp_v6_err
,
1926 .flags
= INET6_PROTO_NOPOLICY
|INET6_PROTO_FINAL
,
1929 static struct inet_protosw tcpv6_protosw
= {
1930 .type
= SOCK_STREAM
,
1931 .protocol
= IPPROTO_TCP
,
1932 .prot
= &tcpv6_prot
,
1933 .ops
= &inet6_stream_ops
,
1934 .flags
= INET_PROTOSW_PERMANENT
|
1938 static int __net_init
tcpv6_net_init(struct net
*net
)
1940 return inet_ctl_sock_create(&net
->ipv6
.tcp_sk
, PF_INET6
,
1941 SOCK_RAW
, IPPROTO_TCP
, net
);
1944 static void __net_exit
tcpv6_net_exit(struct net
*net
)
1946 inet_ctl_sock_destroy(net
->ipv6
.tcp_sk
);
1949 static void __net_exit
tcpv6_net_exit_batch(struct list_head
*net_exit_list
)
1951 inet_twsk_purge(&tcp_hashinfo
, &tcp_death_row
, AF_INET6
);
1954 static struct pernet_operations tcpv6_net_ops
= {
1955 .init
= tcpv6_net_init
,
1956 .exit
= tcpv6_net_exit
,
1957 .exit_batch
= tcpv6_net_exit_batch
,
1960 int __init
tcpv6_init(void)
1964 ret
= inet6_add_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1968 /* register inet6 protocol */
1969 ret
= inet6_register_protosw(&tcpv6_protosw
);
1971 goto out_tcpv6_protocol
;
1973 ret
= register_pernet_subsys(&tcpv6_net_ops
);
1975 goto out_tcpv6_protosw
;
1980 inet6_unregister_protosw(&tcpv6_protosw
);
1982 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1986 void tcpv6_exit(void)
1988 unregister_pernet_subsys(&tcpv6_net_ops
);
1989 inet6_unregister_protosw(&tcpv6_protosw
);
1990 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);