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
)
106 return secure_tcpv6_sequence_number(ipv6_hdr(skb
)->daddr
.s6_addr32
,
107 ipv6_hdr(skb
)->saddr
.s6_addr32
,
109 tcp_hdr(skb
)->source
);
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
;
237 opt
= rcu_dereference_protected(np
->opt
, lockdep_sock_is_held(sk
));
238 final_p
= fl6_update_dst(&fl6
, opt
, &final
);
240 security_sk_classify_flow(sk
, flowi6_to_flowi(&fl6
));
242 dst
= ip6_dst_lookup_flow(sk
, &fl6
, final_p
);
250 sk
->sk_v6_rcv_saddr
= *saddr
;
253 /* set the source address */
255 inet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
257 sk
->sk_gso_type
= SKB_GSO_TCPV6
;
258 ip6_dst_store(sk
, dst
, NULL
, NULL
);
260 if (tcp_death_row
.sysctl_tw_recycle
&&
261 !tp
->rx_opt
.ts_recent_stamp
&&
262 ipv6_addr_equal(&fl6
.daddr
, &sk
->sk_v6_daddr
))
263 tcp_fetch_timewait_stamp(sk
, dst
);
265 icsk
->icsk_ext_hdr_len
= 0;
267 icsk
->icsk_ext_hdr_len
= opt
->opt_flen
+
270 tp
->rx_opt
.mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) - sizeof(struct ipv6hdr
);
272 inet
->inet_dport
= usin
->sin6_port
;
274 tcp_set_state(sk
, TCP_SYN_SENT
);
275 err
= inet6_hash_connect(&tcp_death_row
, sk
);
281 if (!tp
->write_seq
&& likely(!tp
->repair
))
282 tp
->write_seq
= secure_tcpv6_sequence_number(np
->saddr
.s6_addr32
,
283 sk
->sk_v6_daddr
.s6_addr32
,
287 err
= tcp_connect(sk
);
294 tcp_set_state(sk
, TCP_CLOSE
);
297 inet
->inet_dport
= 0;
298 sk
->sk_route_caps
= 0;
302 static void tcp_v6_mtu_reduced(struct sock
*sk
)
304 struct dst_entry
*dst
;
306 if ((1 << sk
->sk_state
) & (TCPF_LISTEN
| TCPF_CLOSE
))
309 dst
= inet6_csk_update_pmtu(sk
, tcp_sk(sk
)->mtu_info
);
313 if (inet_csk(sk
)->icsk_pmtu_cookie
> dst_mtu(dst
)) {
314 tcp_sync_mss(sk
, dst_mtu(dst
));
315 tcp_simple_retransmit(sk
);
319 static void tcp_v6_err(struct sk_buff
*skb
, struct inet6_skb_parm
*opt
,
320 u8 type
, u8 code
, int offset
, __be32 info
)
322 const struct ipv6hdr
*hdr
= (const struct ipv6hdr
*)skb
->data
;
323 const struct tcphdr
*th
= (struct tcphdr
*)(skb
->data
+offset
);
324 struct net
*net
= dev_net(skb
->dev
);
325 struct request_sock
*fastopen
;
326 struct ipv6_pinfo
*np
;
333 sk
= __inet6_lookup_established(net
, &tcp_hashinfo
,
334 &hdr
->daddr
, th
->dest
,
335 &hdr
->saddr
, ntohs(th
->source
),
339 __ICMP6_INC_STATS(net
, __in6_dev_get(skb
->dev
),
344 if (sk
->sk_state
== TCP_TIME_WAIT
) {
345 inet_twsk_put(inet_twsk(sk
));
348 seq
= ntohl(th
->seq
);
349 fatal
= icmpv6_err_convert(type
, code
, &err
);
350 if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
351 return tcp_req_err(sk
, seq
, fatal
);
354 if (sock_owned_by_user(sk
) && type
!= ICMPV6_PKT_TOOBIG
)
355 __NET_INC_STATS(net
, LINUX_MIB_LOCKDROPPEDICMPS
);
357 if (sk
->sk_state
== TCP_CLOSE
)
360 if (ipv6_hdr(skb
)->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
361 __NET_INC_STATS(net
, LINUX_MIB_TCPMINTTLDROP
);
366 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
367 fastopen
= tp
->fastopen_rsk
;
368 snd_una
= fastopen
? tcp_rsk(fastopen
)->snt_isn
: tp
->snd_una
;
369 if (sk
->sk_state
!= TCP_LISTEN
&&
370 !between(seq
, snd_una
, tp
->snd_nxt
)) {
371 __NET_INC_STATS(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
377 if (type
== NDISC_REDIRECT
) {
378 struct dst_entry
*dst
= __sk_dst_check(sk
, np
->dst_cookie
);
381 dst
->ops
->redirect(dst
, sk
, skb
);
385 if (type
== ICMPV6_PKT_TOOBIG
) {
386 /* We are not interested in TCP_LISTEN and open_requests
387 * (SYN-ACKs send out by Linux are always <576bytes so
388 * they should go through unfragmented).
390 if (sk
->sk_state
== TCP_LISTEN
)
393 if (!ip6_sk_accept_pmtu(sk
))
396 tp
->mtu_info
= ntohl(info
);
397 if (!sock_owned_by_user(sk
))
398 tcp_v6_mtu_reduced(sk
);
399 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED
,
406 /* Might be for an request_sock */
407 switch (sk
->sk_state
) {
410 /* Only in fast or simultaneous open. If a fast open socket is
411 * is already accepted it is treated as a connected one below.
413 if (fastopen
&& !fastopen
->sk
)
416 if (!sock_owned_by_user(sk
)) {
418 sk
->sk_error_report(sk
); /* Wake people up to see the error (see connect in sock.c) */
422 sk
->sk_err_soft
= err
;
426 if (!sock_owned_by_user(sk
) && np
->recverr
) {
428 sk
->sk_error_report(sk
);
430 sk
->sk_err_soft
= err
;
438 static int tcp_v6_send_synack(const struct sock
*sk
, struct dst_entry
*dst
,
440 struct request_sock
*req
,
441 struct tcp_fastopen_cookie
*foc
,
442 enum tcp_synack_type synack_type
)
444 struct inet_request_sock
*ireq
= inet_rsk(req
);
445 struct ipv6_pinfo
*np
= inet6_sk(sk
);
446 struct flowi6
*fl6
= &fl
->u
.ip6
;
450 /* First, grab a route. */
451 if (!dst
&& (dst
= inet6_csk_route_req(sk
, fl6
, req
,
452 IPPROTO_TCP
)) == NULL
)
455 skb
= tcp_make_synack(sk
, dst
, req
, foc
, synack_type
);
458 __tcp_v6_send_check(skb
, &ireq
->ir_v6_loc_addr
,
459 &ireq
->ir_v6_rmt_addr
);
461 fl6
->daddr
= ireq
->ir_v6_rmt_addr
;
462 if (np
->repflow
&& ireq
->pktopts
)
463 fl6
->flowlabel
= ip6_flowlabel(ipv6_hdr(ireq
->pktopts
));
466 err
= ip6_xmit(sk
, skb
, fl6
, rcu_dereference(np
->opt
),
469 err
= net_xmit_eval(err
);
477 static void tcp_v6_reqsk_destructor(struct request_sock
*req
)
479 kfree_skb(inet_rsk(req
)->pktopts
);
482 #ifdef CONFIG_TCP_MD5SIG
483 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(const struct sock
*sk
,
484 const struct in6_addr
*addr
)
486 return tcp_md5_do_lookup(sk
, (union tcp_md5_addr
*)addr
, AF_INET6
);
489 static struct tcp_md5sig_key
*tcp_v6_md5_lookup(const struct sock
*sk
,
490 const struct sock
*addr_sk
)
492 return tcp_v6_md5_do_lookup(sk
, &addr_sk
->sk_v6_daddr
);
495 static int tcp_v6_parse_md5_keys(struct sock
*sk
, char __user
*optval
,
498 struct tcp_md5sig cmd
;
499 struct sockaddr_in6
*sin6
= (struct sockaddr_in6
*)&cmd
.tcpm_addr
;
501 if (optlen
< sizeof(cmd
))
504 if (copy_from_user(&cmd
, optval
, sizeof(cmd
)))
507 if (sin6
->sin6_family
!= AF_INET6
)
510 if (!cmd
.tcpm_keylen
) {
511 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
512 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
514 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
518 if (cmd
.tcpm_keylen
> TCP_MD5SIG_MAXKEYLEN
)
521 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
522 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
523 AF_INET
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
525 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
526 AF_INET6
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
529 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool
*hp
,
530 const struct in6_addr
*daddr
,
531 const struct in6_addr
*saddr
, int nbytes
)
533 struct tcp6_pseudohdr
*bp
;
534 struct scatterlist sg
;
536 bp
= &hp
->md5_blk
.ip6
;
537 /* 1. TCP pseudo-header (RFC2460) */
540 bp
->protocol
= cpu_to_be32(IPPROTO_TCP
);
541 bp
->len
= cpu_to_be32(nbytes
);
543 sg_init_one(&sg
, bp
, sizeof(*bp
));
544 ahash_request_set_crypt(hp
->md5_req
, &sg
, NULL
, sizeof(*bp
));
545 return crypto_ahash_update(hp
->md5_req
);
548 static int tcp_v6_md5_hash_hdr(char *md5_hash
, struct tcp_md5sig_key
*key
,
549 const struct in6_addr
*daddr
, struct in6_addr
*saddr
,
550 const struct tcphdr
*th
)
552 struct tcp_md5sig_pool
*hp
;
553 struct ahash_request
*req
;
555 hp
= tcp_get_md5sig_pool();
557 goto clear_hash_noput
;
560 if (crypto_ahash_init(req
))
562 if (tcp_v6_md5_hash_pseudoheader(hp
, daddr
, saddr
, th
->doff
<< 2))
564 if (tcp_md5_hash_header(hp
, th
))
566 if (tcp_md5_hash_key(hp
, key
))
568 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
569 if (crypto_ahash_final(req
))
572 tcp_put_md5sig_pool();
576 tcp_put_md5sig_pool();
578 memset(md5_hash
, 0, 16);
582 static int tcp_v6_md5_hash_skb(char *md5_hash
,
583 const struct tcp_md5sig_key
*key
,
584 const struct sock
*sk
,
585 const struct sk_buff
*skb
)
587 const struct in6_addr
*saddr
, *daddr
;
588 struct tcp_md5sig_pool
*hp
;
589 struct ahash_request
*req
;
590 const struct tcphdr
*th
= tcp_hdr(skb
);
592 if (sk
) { /* valid for establish/request sockets */
593 saddr
= &sk
->sk_v6_rcv_saddr
;
594 daddr
= &sk
->sk_v6_daddr
;
596 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
597 saddr
= &ip6h
->saddr
;
598 daddr
= &ip6h
->daddr
;
601 hp
= tcp_get_md5sig_pool();
603 goto clear_hash_noput
;
606 if (crypto_ahash_init(req
))
609 if (tcp_v6_md5_hash_pseudoheader(hp
, daddr
, saddr
, skb
->len
))
611 if (tcp_md5_hash_header(hp
, th
))
613 if (tcp_md5_hash_skb_data(hp
, skb
, th
->doff
<< 2))
615 if (tcp_md5_hash_key(hp
, key
))
617 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
618 if (crypto_ahash_final(req
))
621 tcp_put_md5sig_pool();
625 tcp_put_md5sig_pool();
627 memset(md5_hash
, 0, 16);
633 static bool tcp_v6_inbound_md5_hash(const struct sock
*sk
,
634 const struct sk_buff
*skb
)
636 #ifdef CONFIG_TCP_MD5SIG
637 const __u8
*hash_location
= NULL
;
638 struct tcp_md5sig_key
*hash_expected
;
639 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
640 const struct tcphdr
*th
= tcp_hdr(skb
);
644 hash_expected
= tcp_v6_md5_do_lookup(sk
, &ip6h
->saddr
);
645 hash_location
= tcp_parse_md5sig_option(th
);
647 /* We've parsed the options - do we have a hash? */
648 if (!hash_expected
&& !hash_location
)
651 if (hash_expected
&& !hash_location
) {
652 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5NOTFOUND
);
656 if (!hash_expected
&& hash_location
) {
657 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5UNEXPECTED
);
661 /* check the signature */
662 genhash
= tcp_v6_md5_hash_skb(newhash
,
666 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0) {
667 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
668 genhash
? "failed" : "mismatch",
669 &ip6h
->saddr
, ntohs(th
->source
),
670 &ip6h
->daddr
, ntohs(th
->dest
));
677 static void tcp_v6_init_req(struct request_sock
*req
,
678 const struct sock
*sk_listener
,
681 struct inet_request_sock
*ireq
= inet_rsk(req
);
682 const struct ipv6_pinfo
*np
= inet6_sk(sk_listener
);
684 ireq
->ir_v6_rmt_addr
= ipv6_hdr(skb
)->saddr
;
685 ireq
->ir_v6_loc_addr
= ipv6_hdr(skb
)->daddr
;
687 /* So that link locals have meaning */
688 if (!sk_listener
->sk_bound_dev_if
&&
689 ipv6_addr_type(&ireq
->ir_v6_rmt_addr
) & IPV6_ADDR_LINKLOCAL
)
690 ireq
->ir_iif
= tcp_v6_iif(skb
);
692 if (!TCP_SKB_CB(skb
)->tcp_tw_isn
&&
693 (ipv6_opt_accepted(sk_listener
, skb
, &TCP_SKB_CB(skb
)->header
.h6
) ||
694 np
->rxopt
.bits
.rxinfo
||
695 np
->rxopt
.bits
.rxoinfo
|| np
->rxopt
.bits
.rxhlim
||
696 np
->rxopt
.bits
.rxohlim
|| np
->repflow
)) {
697 atomic_inc(&skb
->users
);
702 static struct dst_entry
*tcp_v6_route_req(const struct sock
*sk
,
704 const struct request_sock
*req
,
709 return inet6_csk_route_req(sk
, &fl
->u
.ip6
, req
, IPPROTO_TCP
);
712 struct request_sock_ops tcp6_request_sock_ops __read_mostly
= {
714 .obj_size
= sizeof(struct tcp6_request_sock
),
715 .rtx_syn_ack
= tcp_rtx_synack
,
716 .send_ack
= tcp_v6_reqsk_send_ack
,
717 .destructor
= tcp_v6_reqsk_destructor
,
718 .send_reset
= tcp_v6_send_reset
,
719 .syn_ack_timeout
= tcp_syn_ack_timeout
,
722 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops
= {
723 .mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) -
724 sizeof(struct ipv6hdr
),
725 #ifdef CONFIG_TCP_MD5SIG
726 .req_md5_lookup
= tcp_v6_md5_lookup
,
727 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
729 .init_req
= tcp_v6_init_req
,
730 #ifdef CONFIG_SYN_COOKIES
731 .cookie_init_seq
= cookie_v6_init_sequence
,
733 .route_req
= tcp_v6_route_req
,
734 .init_seq
= tcp_v6_init_sequence
,
735 .send_synack
= tcp_v6_send_synack
,
738 static void tcp_v6_send_response(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
739 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
,
740 int oif
, struct tcp_md5sig_key
*key
, int rst
,
741 u8 tclass
, u32 label
)
743 const struct tcphdr
*th
= tcp_hdr(skb
);
745 struct sk_buff
*buff
;
747 struct net
*net
= sk
? sock_net(sk
) : dev_net(skb_dst(skb
)->dev
);
748 struct sock
*ctl_sk
= net
->ipv6
.tcp_sk
;
749 unsigned int tot_len
= sizeof(struct tcphdr
);
750 struct dst_entry
*dst
;
754 tot_len
+= TCPOLEN_TSTAMP_ALIGNED
;
755 #ifdef CONFIG_TCP_MD5SIG
757 tot_len
+= TCPOLEN_MD5SIG_ALIGNED
;
760 buff
= alloc_skb(MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
,
765 skb_reserve(buff
, MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
);
767 t1
= (struct tcphdr
*) skb_push(buff
, tot_len
);
768 skb_reset_transport_header(buff
);
770 /* Swap the send and the receive. */
771 memset(t1
, 0, sizeof(*t1
));
772 t1
->dest
= th
->source
;
773 t1
->source
= th
->dest
;
774 t1
->doff
= tot_len
/ 4;
775 t1
->seq
= htonl(seq
);
776 t1
->ack_seq
= htonl(ack
);
777 t1
->ack
= !rst
|| !th
->ack
;
779 t1
->window
= htons(win
);
781 topt
= (__be32
*)(t1
+ 1);
784 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
785 (TCPOPT_TIMESTAMP
<< 8) | TCPOLEN_TIMESTAMP
);
786 *topt
++ = htonl(tsval
);
787 *topt
++ = htonl(tsecr
);
790 #ifdef CONFIG_TCP_MD5SIG
792 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
793 (TCPOPT_MD5SIG
<< 8) | TCPOLEN_MD5SIG
);
794 tcp_v6_md5_hash_hdr((__u8
*)topt
, key
,
795 &ipv6_hdr(skb
)->saddr
,
796 &ipv6_hdr(skb
)->daddr
, t1
);
800 memset(&fl6
, 0, sizeof(fl6
));
801 fl6
.daddr
= ipv6_hdr(skb
)->saddr
;
802 fl6
.saddr
= ipv6_hdr(skb
)->daddr
;
803 fl6
.flowlabel
= label
;
805 buff
->ip_summed
= CHECKSUM_PARTIAL
;
808 __tcp_v6_send_check(buff
, &fl6
.saddr
, &fl6
.daddr
);
810 fl6
.flowi6_proto
= IPPROTO_TCP
;
811 if (rt6_need_strict(&fl6
.daddr
) && !oif
)
812 fl6
.flowi6_oif
= tcp_v6_iif(skb
);
814 if (!oif
&& netif_index_is_l3_master(net
, skb
->skb_iif
))
817 fl6
.flowi6_oif
= oif
;
820 fl6
.flowi6_mark
= IP6_REPLY_MARK(net
, skb
->mark
);
821 fl6
.fl6_dport
= t1
->dest
;
822 fl6
.fl6_sport
= t1
->source
;
823 security_skb_classify_flow(skb
, flowi6_to_flowi(&fl6
));
825 /* Pass a socket to ip6_dst_lookup either it is for RST
826 * Underlying function will use this to retrieve the network
829 dst
= ip6_dst_lookup_flow(ctl_sk
, &fl6
, NULL
);
831 skb_dst_set(buff
, dst
);
832 ip6_xmit(ctl_sk
, buff
, &fl6
, NULL
, tclass
);
833 TCP_INC_STATS(net
, TCP_MIB_OUTSEGS
);
835 TCP_INC_STATS(net
, TCP_MIB_OUTRSTS
);
842 static void tcp_v6_send_reset(const struct sock
*sk
, struct sk_buff
*skb
)
844 const struct tcphdr
*th
= tcp_hdr(skb
);
845 u32 seq
= 0, ack_seq
= 0;
846 struct tcp_md5sig_key
*key
= NULL
;
847 #ifdef CONFIG_TCP_MD5SIG
848 const __u8
*hash_location
= NULL
;
849 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
850 unsigned char newhash
[16];
852 struct sock
*sk1
= NULL
;
859 /* If sk not NULL, it means we did a successful lookup and incoming
860 * route had to be correct. prequeue might have dropped our dst.
862 if (!sk
&& !ipv6_unicast_destination(skb
))
865 #ifdef CONFIG_TCP_MD5SIG
867 hash_location
= tcp_parse_md5sig_option(th
);
868 if (sk
&& sk_fullsock(sk
)) {
869 key
= tcp_v6_md5_do_lookup(sk
, &ipv6h
->saddr
);
870 } else if (hash_location
) {
872 * active side is lost. Try to find listening socket through
873 * source port, and then find md5 key through listening socket.
874 * we are not loose security here:
875 * Incoming packet is checked with md5 hash with finding key,
876 * no RST generated if md5 hash doesn't match.
878 sk1
= inet6_lookup_listener(dev_net(skb_dst(skb
)->dev
),
879 &tcp_hashinfo
, NULL
, 0,
881 th
->source
, &ipv6h
->daddr
,
882 ntohs(th
->source
), tcp_v6_iif(skb
));
886 key
= tcp_v6_md5_do_lookup(sk1
, &ipv6h
->saddr
);
890 genhash
= tcp_v6_md5_hash_skb(newhash
, key
, NULL
, skb
);
891 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0)
897 seq
= ntohl(th
->ack_seq
);
899 ack_seq
= ntohl(th
->seq
) + th
->syn
+ th
->fin
+ skb
->len
-
902 oif
= sk
? sk
->sk_bound_dev_if
: 0;
903 tcp_v6_send_response(sk
, skb
, seq
, ack_seq
, 0, 0, 0, oif
, key
, 1, 0, 0);
905 #ifdef CONFIG_TCP_MD5SIG
911 static void tcp_v6_send_ack(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
912 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
, int oif
,
913 struct tcp_md5sig_key
*key
, u8 tclass
,
916 tcp_v6_send_response(sk
, skb
, seq
, ack
, win
, tsval
, tsecr
, oif
, key
, 0,
920 static void tcp_v6_timewait_ack(struct sock
*sk
, struct sk_buff
*skb
)
922 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
923 struct tcp_timewait_sock
*tcptw
= tcp_twsk(sk
);
925 tcp_v6_send_ack(sk
, skb
, tcptw
->tw_snd_nxt
, tcptw
->tw_rcv_nxt
,
926 tcptw
->tw_rcv_wnd
>> tw
->tw_rcv_wscale
,
927 tcp_time_stamp
+ tcptw
->tw_ts_offset
,
928 tcptw
->tw_ts_recent
, tw
->tw_bound_dev_if
, tcp_twsk_md5_key(tcptw
),
929 tw
->tw_tclass
, cpu_to_be32(tw
->tw_flowlabel
));
934 static void tcp_v6_reqsk_send_ack(const struct sock
*sk
, struct sk_buff
*skb
,
935 struct request_sock
*req
)
937 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
938 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
940 tcp_v6_send_ack(sk
, skb
, (sk
->sk_state
== TCP_LISTEN
) ?
941 tcp_rsk(req
)->snt_isn
+ 1 : tcp_sk(sk
)->snd_nxt
,
942 tcp_rsk(req
)->rcv_nxt
, req
->rsk_rcv_wnd
,
943 tcp_time_stamp
, req
->ts_recent
, sk
->sk_bound_dev_if
,
944 tcp_v6_md5_do_lookup(sk
, &ipv6_hdr(skb
)->daddr
),
949 static struct sock
*tcp_v6_cookie_check(struct sock
*sk
, struct sk_buff
*skb
)
951 #ifdef CONFIG_SYN_COOKIES
952 const struct tcphdr
*th
= tcp_hdr(skb
);
955 sk
= cookie_v6_check(sk
, skb
);
960 static int tcp_v6_conn_request(struct sock
*sk
, struct sk_buff
*skb
)
962 if (skb
->protocol
== htons(ETH_P_IP
))
963 return tcp_v4_conn_request(sk
, skb
);
965 if (!ipv6_unicast_destination(skb
))
968 return tcp_conn_request(&tcp6_request_sock_ops
,
969 &tcp_request_sock_ipv6_ops
, sk
, skb
);
973 return 0; /* don't send reset */
976 static struct sock
*tcp_v6_syn_recv_sock(const struct sock
*sk
, struct sk_buff
*skb
,
977 struct request_sock
*req
,
978 struct dst_entry
*dst
,
979 struct request_sock
*req_unhash
,
982 struct inet_request_sock
*ireq
;
983 struct ipv6_pinfo
*newnp
;
984 const struct ipv6_pinfo
*np
= inet6_sk(sk
);
985 struct ipv6_txoptions
*opt
;
986 struct tcp6_sock
*newtcp6sk
;
987 struct inet_sock
*newinet
;
988 struct tcp_sock
*newtp
;
990 #ifdef CONFIG_TCP_MD5SIG
991 struct tcp_md5sig_key
*key
;
995 if (skb
->protocol
== htons(ETH_P_IP
)) {
1000 newsk
= tcp_v4_syn_recv_sock(sk
, skb
, req
, dst
,
1001 req_unhash
, own_req
);
1006 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1007 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1009 newinet
= inet_sk(newsk
);
1010 newnp
= inet6_sk(newsk
);
1011 newtp
= tcp_sk(newsk
);
1013 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1015 newnp
->saddr
= newsk
->sk_v6_rcv_saddr
;
1017 inet_csk(newsk
)->icsk_af_ops
= &ipv6_mapped
;
1018 newsk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
1019 #ifdef CONFIG_TCP_MD5SIG
1020 newtp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
1023 newnp
->ipv6_ac_list
= NULL
;
1024 newnp
->ipv6_fl_list
= NULL
;
1025 newnp
->pktoptions
= NULL
;
1027 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1028 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1029 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1031 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1034 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1035 * here, tcp_create_openreq_child now does this for us, see the comment in
1036 * that function for the gory details. -acme
1039 /* It is tricky place. Until this moment IPv4 tcp
1040 worked with IPv6 icsk.icsk_af_ops.
1043 tcp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
1048 ireq
= inet_rsk(req
);
1050 if (sk_acceptq_is_full(sk
))
1054 dst
= inet6_csk_route_req(sk
, &fl6
, req
, IPPROTO_TCP
);
1059 newsk
= tcp_create_openreq_child(sk
, req
, skb
);
1064 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1065 * count here, tcp_create_openreq_child now does this for us, see the
1066 * comment in that function for the gory details. -acme
1069 newsk
->sk_gso_type
= SKB_GSO_TCPV6
;
1070 ip6_dst_store(newsk
, dst
, NULL
, NULL
);
1071 inet6_sk_rx_dst_set(newsk
, skb
);
1073 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1074 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1076 newtp
= tcp_sk(newsk
);
1077 newinet
= inet_sk(newsk
);
1078 newnp
= inet6_sk(newsk
);
1080 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1082 newsk
->sk_v6_daddr
= ireq
->ir_v6_rmt_addr
;
1083 newnp
->saddr
= ireq
->ir_v6_loc_addr
;
1084 newsk
->sk_v6_rcv_saddr
= ireq
->ir_v6_loc_addr
;
1085 newsk
->sk_bound_dev_if
= ireq
->ir_iif
;
1087 /* Now IPv6 options...
1089 First: no IPv4 options.
1091 newinet
->inet_opt
= NULL
;
1092 newnp
->ipv6_ac_list
= NULL
;
1093 newnp
->ipv6_fl_list
= NULL
;
1096 newnp
->rxopt
.all
= np
->rxopt
.all
;
1098 newnp
->pktoptions
= NULL
;
1100 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1101 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1102 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1104 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1106 /* Clone native IPv6 options from listening socket (if any)
1108 Yes, keeping reference count would be much more clever,
1109 but we make one more one thing there: reattach optmem
1112 opt
= rcu_dereference(np
->opt
);
1114 opt
= ipv6_dup_options(newsk
, opt
);
1115 RCU_INIT_POINTER(newnp
->opt
, opt
);
1117 inet_csk(newsk
)->icsk_ext_hdr_len
= 0;
1119 inet_csk(newsk
)->icsk_ext_hdr_len
= opt
->opt_nflen
+
1122 tcp_ca_openreq_child(newsk
, dst
);
1124 tcp_sync_mss(newsk
, dst_mtu(dst
));
1125 newtp
->advmss
= dst_metric_advmss(dst
);
1126 if (tcp_sk(sk
)->rx_opt
.user_mss
&&
1127 tcp_sk(sk
)->rx_opt
.user_mss
< newtp
->advmss
)
1128 newtp
->advmss
= tcp_sk(sk
)->rx_opt
.user_mss
;
1130 tcp_initialize_rcv_mss(newsk
);
1132 newinet
->inet_daddr
= newinet
->inet_saddr
= LOOPBACK4_IPV6
;
1133 newinet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
1135 #ifdef CONFIG_TCP_MD5SIG
1136 /* Copy over the MD5 key from the original socket */
1137 key
= tcp_v6_md5_do_lookup(sk
, &newsk
->sk_v6_daddr
);
1139 /* We're using one, so create a matching key
1140 * on the newsk structure. If we fail to get
1141 * memory, then we end up not copying the key
1144 tcp_md5_do_add(newsk
, (union tcp_md5_addr
*)&newsk
->sk_v6_daddr
,
1145 AF_INET6
, key
->key
, key
->keylen
,
1146 sk_gfp_mask(sk
, GFP_ATOMIC
));
1150 if (__inet_inherit_port(sk
, newsk
) < 0) {
1151 inet_csk_prepare_forced_close(newsk
);
1155 *own_req
= inet_ehash_nolisten(newsk
, req_to_sk(req_unhash
));
1157 tcp_move_syn(newtp
, req
);
1159 /* Clone pktoptions received with SYN, if we own the req */
1160 if (ireq
->pktopts
) {
1161 newnp
->pktoptions
= skb_clone(ireq
->pktopts
,
1162 sk_gfp_mask(sk
, GFP_ATOMIC
));
1163 consume_skb(ireq
->pktopts
);
1164 ireq
->pktopts
= NULL
;
1165 if (newnp
->pktoptions
)
1166 skb_set_owner_r(newnp
->pktoptions
, newsk
);
1173 __NET_INC_STATS(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
1181 /* The socket must have it's spinlock held when we get
1182 * here, unless it is a TCP_LISTEN socket.
1184 * We have a potential double-lock case here, so even when
1185 * doing backlog processing we use the BH locking scheme.
1186 * This is because we cannot sleep with the original spinlock
1189 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
)
1191 struct ipv6_pinfo
*np
= inet6_sk(sk
);
1192 struct tcp_sock
*tp
;
1193 struct sk_buff
*opt_skb
= NULL
;
1195 /* Imagine: socket is IPv6. IPv4 packet arrives,
1196 goes to IPv4 receive handler and backlogged.
1197 From backlog it always goes here. Kerboom...
1198 Fortunately, tcp_rcv_established and rcv_established
1199 handle them correctly, but it is not case with
1200 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1203 if (skb
->protocol
== htons(ETH_P_IP
))
1204 return tcp_v4_do_rcv(sk
, skb
);
1206 if (sk_filter(sk
, skb
))
1210 * socket locking is here for SMP purposes as backlog rcv
1211 * is currently called with bh processing disabled.
1214 /* Do Stevens' IPV6_PKTOPTIONS.
1216 Yes, guys, it is the only place in our code, where we
1217 may make it not affecting IPv4.
1218 The rest of code is protocol independent,
1219 and I do not like idea to uglify IPv4.
1221 Actually, all the idea behind IPV6_PKTOPTIONS
1222 looks not very well thought. For now we latch
1223 options, received in the last packet, enqueued
1224 by tcp. Feel free to propose better solution.
1228 opt_skb
= skb_clone(skb
, sk_gfp_mask(sk
, GFP_ATOMIC
));
1230 if (sk
->sk_state
== TCP_ESTABLISHED
) { /* Fast path */
1231 struct dst_entry
*dst
= sk
->sk_rx_dst
;
1233 sock_rps_save_rxhash(sk
, skb
);
1234 sk_mark_napi_id(sk
, skb
);
1236 if (inet_sk(sk
)->rx_dst_ifindex
!= skb
->skb_iif
||
1237 dst
->ops
->check(dst
, np
->rx_dst_cookie
) == NULL
) {
1239 sk
->sk_rx_dst
= NULL
;
1243 tcp_rcv_established(sk
, skb
, tcp_hdr(skb
), skb
->len
);
1245 goto ipv6_pktoptions
;
1249 if (tcp_checksum_complete(skb
))
1252 if (sk
->sk_state
== TCP_LISTEN
) {
1253 struct sock
*nsk
= tcp_v6_cookie_check(sk
, skb
);
1259 sock_rps_save_rxhash(nsk
, skb
);
1260 sk_mark_napi_id(nsk
, skb
);
1261 if (tcp_child_process(sk
, nsk
, skb
))
1264 __kfree_skb(opt_skb
);
1268 sock_rps_save_rxhash(sk
, skb
);
1270 if (tcp_rcv_state_process(sk
, skb
))
1273 goto ipv6_pktoptions
;
1277 tcp_v6_send_reset(sk
, skb
);
1280 __kfree_skb(opt_skb
);
1284 TCP_INC_STATS(sock_net(sk
), TCP_MIB_CSUMERRORS
);
1285 TCP_INC_STATS(sock_net(sk
), TCP_MIB_INERRS
);
1290 /* Do you ask, what is it?
1292 1. skb was enqueued by tcp.
1293 2. skb is added to tail of read queue, rather than out of order.
1294 3. socket is not in passive state.
1295 4. Finally, it really contains options, which user wants to receive.
1298 if (TCP_SKB_CB(opt_skb
)->end_seq
== tp
->rcv_nxt
&&
1299 !((1 << sk
->sk_state
) & (TCPF_CLOSE
| TCPF_LISTEN
))) {
1300 if (np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
)
1301 np
->mcast_oif
= tcp_v6_iif(opt_skb
);
1302 if (np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
)
1303 np
->mcast_hops
= ipv6_hdr(opt_skb
)->hop_limit
;
1304 if (np
->rxopt
.bits
.rxflow
|| np
->rxopt
.bits
.rxtclass
)
1305 np
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(opt_skb
));
1307 np
->flow_label
= ip6_flowlabel(ipv6_hdr(opt_skb
));
1308 if (ipv6_opt_accepted(sk
, opt_skb
, &TCP_SKB_CB(opt_skb
)->header
.h6
)) {
1309 skb_set_owner_r(opt_skb
, sk
);
1310 opt_skb
= xchg(&np
->pktoptions
, opt_skb
);
1312 __kfree_skb(opt_skb
);
1313 opt_skb
= xchg(&np
->pktoptions
, NULL
);
1321 static void tcp_v6_fill_cb(struct sk_buff
*skb
, const struct ipv6hdr
*hdr
,
1322 const struct tcphdr
*th
)
1324 /* This is tricky: we move IP6CB at its correct location into
1325 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because
1326 * _decode_session6() uses IP6CB().
1327 * barrier() makes sure compiler won't play aliasing games.
1329 memmove(&TCP_SKB_CB(skb
)->header
.h6
, IP6CB(skb
),
1330 sizeof(struct inet6_skb_parm
));
1333 TCP_SKB_CB(skb
)->seq
= ntohl(th
->seq
);
1334 TCP_SKB_CB(skb
)->end_seq
= (TCP_SKB_CB(skb
)->seq
+ th
->syn
+ th
->fin
+
1335 skb
->len
- th
->doff
*4);
1336 TCP_SKB_CB(skb
)->ack_seq
= ntohl(th
->ack_seq
);
1337 TCP_SKB_CB(skb
)->tcp_flags
= tcp_flag_byte(th
);
1338 TCP_SKB_CB(skb
)->tcp_tw_isn
= 0;
1339 TCP_SKB_CB(skb
)->ip_dsfield
= ipv6_get_dsfield(hdr
);
1340 TCP_SKB_CB(skb
)->sacked
= 0;
1343 static void tcp_v6_restore_cb(struct sk_buff
*skb
)
1345 /* We need to move header back to the beginning if xfrm6_policy_check()
1346 * and tcp_v6_fill_cb() are going to be called again.
1348 memmove(IP6CB(skb
), &TCP_SKB_CB(skb
)->header
.h6
,
1349 sizeof(struct inet6_skb_parm
));
1352 static int tcp_v6_rcv(struct sk_buff
*skb
)
1354 const struct tcphdr
*th
;
1355 const struct ipv6hdr
*hdr
;
1359 struct net
*net
= dev_net(skb
->dev
);
1361 if (skb
->pkt_type
!= PACKET_HOST
)
1365 * Count it even if it's bad.
1367 __TCP_INC_STATS(net
, TCP_MIB_INSEGS
);
1369 if (!pskb_may_pull(skb
, sizeof(struct tcphdr
)))
1372 th
= (const struct tcphdr
*)skb
->data
;
1374 if (unlikely(th
->doff
< sizeof(struct tcphdr
)/4))
1376 if (!pskb_may_pull(skb
, th
->doff
*4))
1379 if (skb_checksum_init(skb
, IPPROTO_TCP
, ip6_compute_pseudo
))
1382 th
= (const struct tcphdr
*)skb
->data
;
1383 hdr
= ipv6_hdr(skb
);
1386 sk
= __inet6_lookup_skb(&tcp_hashinfo
, skb
, __tcp_hdrlen(th
),
1387 th
->source
, th
->dest
, inet6_iif(skb
),
1393 if (sk
->sk_state
== TCP_TIME_WAIT
)
1396 if (sk
->sk_state
== TCP_NEW_SYN_RECV
) {
1397 struct request_sock
*req
= inet_reqsk(sk
);
1400 sk
= req
->rsk_listener
;
1401 tcp_v6_fill_cb(skb
, hdr
, th
);
1402 if (tcp_v6_inbound_md5_hash(sk
, skb
)) {
1406 if (unlikely(sk
->sk_state
!= TCP_LISTEN
)) {
1407 inet_csk_reqsk_queue_drop_and_put(sk
, req
);
1412 nsk
= tcp_check_req(sk
, skb
, req
, false);
1415 goto discard_and_relse
;
1419 tcp_v6_restore_cb(skb
);
1420 } else if (tcp_child_process(sk
, nsk
, skb
)) {
1421 tcp_v6_send_reset(nsk
, skb
);
1422 goto discard_and_relse
;
1428 if (hdr
->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
1429 __NET_INC_STATS(net
, LINUX_MIB_TCPMINTTLDROP
);
1430 goto discard_and_relse
;
1433 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
1434 goto discard_and_relse
;
1436 tcp_v6_fill_cb(skb
, hdr
, th
);
1438 if (tcp_v6_inbound_md5_hash(sk
, skb
))
1439 goto discard_and_relse
;
1441 if (sk_filter(sk
, skb
))
1442 goto discard_and_relse
;
1446 if (sk
->sk_state
== TCP_LISTEN
) {
1447 ret
= tcp_v6_do_rcv(sk
, skb
);
1448 goto put_and_return
;
1451 sk_incoming_cpu_update(sk
);
1453 bh_lock_sock_nested(sk
);
1454 tcp_segs_in(tcp_sk(sk
), skb
);
1456 if (!sock_owned_by_user(sk
)) {
1457 if (!tcp_prequeue(sk
, skb
))
1458 ret
= tcp_v6_do_rcv(sk
, skb
);
1459 } else if (unlikely(sk_add_backlog(sk
, skb
,
1460 sk
->sk_rcvbuf
+ sk
->sk_sndbuf
))) {
1462 __NET_INC_STATS(net
, LINUX_MIB_TCPBACKLOGDROP
);
1463 goto discard_and_relse
;
1470 return ret
? -1 : 0;
1473 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
1476 tcp_v6_fill_cb(skb
, hdr
, th
);
1478 if (tcp_checksum_complete(skb
)) {
1480 __TCP_INC_STATS(net
, TCP_MIB_CSUMERRORS
);
1482 __TCP_INC_STATS(net
, TCP_MIB_INERRS
);
1484 tcp_v6_send_reset(NULL
, skb
);
1492 sk_drops_add(sk
, skb
);
1498 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
)) {
1499 inet_twsk_put(inet_twsk(sk
));
1503 tcp_v6_fill_cb(skb
, hdr
, th
);
1505 if (tcp_checksum_complete(skb
)) {
1506 inet_twsk_put(inet_twsk(sk
));
1510 switch (tcp_timewait_state_process(inet_twsk(sk
), skb
, th
)) {
1515 sk2
= inet6_lookup_listener(dev_net(skb
->dev
), &tcp_hashinfo
,
1516 skb
, __tcp_hdrlen(th
),
1517 &ipv6_hdr(skb
)->saddr
, th
->source
,
1518 &ipv6_hdr(skb
)->daddr
,
1519 ntohs(th
->dest
), tcp_v6_iif(skb
));
1521 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
1522 inet_twsk_deschedule_put(tw
);
1524 tcp_v6_restore_cb(skb
);
1528 /* Fall through to ACK */
1531 tcp_v6_timewait_ack(sk
, skb
);
1534 tcp_v6_restore_cb(skb
);
1535 tcp_v6_send_reset(sk
, skb
);
1536 inet_twsk_deschedule_put(inet_twsk(sk
));
1538 case TCP_TW_SUCCESS
:
1544 static void tcp_v6_early_demux(struct sk_buff
*skb
)
1546 const struct ipv6hdr
*hdr
;
1547 const struct tcphdr
*th
;
1550 if (skb
->pkt_type
!= PACKET_HOST
)
1553 if (!pskb_may_pull(skb
, skb_transport_offset(skb
) + sizeof(struct tcphdr
)))
1556 hdr
= ipv6_hdr(skb
);
1559 if (th
->doff
< sizeof(struct tcphdr
) / 4)
1562 /* Note : We use inet6_iif() here, not tcp_v6_iif() */
1563 sk
= __inet6_lookup_established(dev_net(skb
->dev
), &tcp_hashinfo
,
1564 &hdr
->saddr
, th
->source
,
1565 &hdr
->daddr
, ntohs(th
->dest
),
1569 skb
->destructor
= sock_edemux
;
1570 if (sk_fullsock(sk
)) {
1571 struct dst_entry
*dst
= READ_ONCE(sk
->sk_rx_dst
);
1574 dst
= dst_check(dst
, inet6_sk(sk
)->rx_dst_cookie
);
1576 inet_sk(sk
)->rx_dst_ifindex
== skb
->skb_iif
)
1577 skb_dst_set_noref(skb
, dst
);
1582 static struct timewait_sock_ops tcp6_timewait_sock_ops
= {
1583 .twsk_obj_size
= sizeof(struct tcp6_timewait_sock
),
1584 .twsk_unique
= tcp_twsk_unique
,
1585 .twsk_destructor
= tcp_twsk_destructor
,
1588 static const struct inet_connection_sock_af_ops ipv6_specific
= {
1589 .queue_xmit
= inet6_csk_xmit
,
1590 .send_check
= tcp_v6_send_check
,
1591 .rebuild_header
= inet6_sk_rebuild_header
,
1592 .sk_rx_dst_set
= inet6_sk_rx_dst_set
,
1593 .conn_request
= tcp_v6_conn_request
,
1594 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1595 .net_header_len
= sizeof(struct ipv6hdr
),
1596 .net_frag_header_len
= sizeof(struct frag_hdr
),
1597 .setsockopt
= ipv6_setsockopt
,
1598 .getsockopt
= ipv6_getsockopt
,
1599 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1600 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1601 .bind_conflict
= inet6_csk_bind_conflict
,
1602 #ifdef CONFIG_COMPAT
1603 .compat_setsockopt
= compat_ipv6_setsockopt
,
1604 .compat_getsockopt
= compat_ipv6_getsockopt
,
1606 .mtu_reduced
= tcp_v6_mtu_reduced
,
1609 #ifdef CONFIG_TCP_MD5SIG
1610 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
= {
1611 .md5_lookup
= tcp_v6_md5_lookup
,
1612 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
1613 .md5_parse
= tcp_v6_parse_md5_keys
,
1618 * TCP over IPv4 via INET6 API
1620 static const struct inet_connection_sock_af_ops ipv6_mapped
= {
1621 .queue_xmit
= ip_queue_xmit
,
1622 .send_check
= tcp_v4_send_check
,
1623 .rebuild_header
= inet_sk_rebuild_header
,
1624 .sk_rx_dst_set
= inet_sk_rx_dst_set
,
1625 .conn_request
= tcp_v6_conn_request
,
1626 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1627 .net_header_len
= sizeof(struct iphdr
),
1628 .setsockopt
= ipv6_setsockopt
,
1629 .getsockopt
= ipv6_getsockopt
,
1630 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1631 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1632 .bind_conflict
= inet6_csk_bind_conflict
,
1633 #ifdef CONFIG_COMPAT
1634 .compat_setsockopt
= compat_ipv6_setsockopt
,
1635 .compat_getsockopt
= compat_ipv6_getsockopt
,
1637 .mtu_reduced
= tcp_v4_mtu_reduced
,
1640 #ifdef CONFIG_TCP_MD5SIG
1641 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
= {
1642 .md5_lookup
= tcp_v4_md5_lookup
,
1643 .calc_md5_hash
= tcp_v4_md5_hash_skb
,
1644 .md5_parse
= tcp_v6_parse_md5_keys
,
1648 /* NOTE: A lot of things set to zero explicitly by call to
1649 * sk_alloc() so need not be done here.
1651 static int tcp_v6_init_sock(struct sock
*sk
)
1653 struct inet_connection_sock
*icsk
= inet_csk(sk
);
1657 icsk
->icsk_af_ops
= &ipv6_specific
;
1659 #ifdef CONFIG_TCP_MD5SIG
1660 tcp_sk(sk
)->af_specific
= &tcp_sock_ipv6_specific
;
1666 static void tcp_v6_destroy_sock(struct sock
*sk
)
1668 tcp_v4_destroy_sock(sk
);
1669 inet6_destroy_sock(sk
);
1672 #ifdef CONFIG_PROC_FS
1673 /* Proc filesystem TCPv6 sock list dumping. */
1674 static void get_openreq6(struct seq_file
*seq
,
1675 const struct request_sock
*req
, int i
)
1677 long ttd
= req
->rsk_timer
.expires
- jiffies
;
1678 const struct in6_addr
*src
= &inet_rsk(req
)->ir_v6_loc_addr
;
1679 const struct in6_addr
*dest
= &inet_rsk(req
)->ir_v6_rmt_addr
;
1685 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1686 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n",
1688 src
->s6_addr32
[0], src
->s6_addr32
[1],
1689 src
->s6_addr32
[2], src
->s6_addr32
[3],
1690 inet_rsk(req
)->ir_num
,
1691 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1692 dest
->s6_addr32
[2], dest
->s6_addr32
[3],
1693 ntohs(inet_rsk(req
)->ir_rmt_port
),
1695 0, 0, /* could print option size, but that is af dependent. */
1696 1, /* timers active (only the expire timer) */
1697 jiffies_to_clock_t(ttd
),
1699 from_kuid_munged(seq_user_ns(seq
),
1700 sock_i_uid(req
->rsk_listener
)),
1701 0, /* non standard timer */
1702 0, /* open_requests have no inode */
1706 static void get_tcp6_sock(struct seq_file
*seq
, struct sock
*sp
, int i
)
1708 const struct in6_addr
*dest
, *src
;
1711 unsigned long timer_expires
;
1712 const struct inet_sock
*inet
= inet_sk(sp
);
1713 const struct tcp_sock
*tp
= tcp_sk(sp
);
1714 const struct inet_connection_sock
*icsk
= inet_csk(sp
);
1715 const struct fastopen_queue
*fastopenq
= &icsk
->icsk_accept_queue
.fastopenq
;
1719 dest
= &sp
->sk_v6_daddr
;
1720 src
= &sp
->sk_v6_rcv_saddr
;
1721 destp
= ntohs(inet
->inet_dport
);
1722 srcp
= ntohs(inet
->inet_sport
);
1724 if (icsk
->icsk_pending
== ICSK_TIME_RETRANS
) {
1726 timer_expires
= icsk
->icsk_timeout
;
1727 } else if (icsk
->icsk_pending
== ICSK_TIME_PROBE0
) {
1729 timer_expires
= icsk
->icsk_timeout
;
1730 } else if (timer_pending(&sp
->sk_timer
)) {
1732 timer_expires
= sp
->sk_timer
.expires
;
1735 timer_expires
= jiffies
;
1738 state
= sk_state_load(sp
);
1739 if (state
== TCP_LISTEN
)
1740 rx_queue
= sp
->sk_ack_backlog
;
1742 /* Because we don't lock the socket,
1743 * we might find a transient negative value.
1745 rx_queue
= max_t(int, tp
->rcv_nxt
- tp
->copied_seq
, 0);
1748 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1749 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
1751 src
->s6_addr32
[0], src
->s6_addr32
[1],
1752 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1753 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1754 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1756 tp
->write_seq
- tp
->snd_una
,
1759 jiffies_delta_to_clock_t(timer_expires
- jiffies
),
1760 icsk
->icsk_retransmits
,
1761 from_kuid_munged(seq_user_ns(seq
), sock_i_uid(sp
)),
1762 icsk
->icsk_probes_out
,
1764 atomic_read(&sp
->sk_refcnt
), sp
,
1765 jiffies_to_clock_t(icsk
->icsk_rto
),
1766 jiffies_to_clock_t(icsk
->icsk_ack
.ato
),
1767 (icsk
->icsk_ack
.quick
<< 1) | icsk
->icsk_ack
.pingpong
,
1769 state
== TCP_LISTEN
?
1770 fastopenq
->max_qlen
:
1771 (tcp_in_initial_slowstart(tp
) ? -1 : tp
->snd_ssthresh
)
1775 static void get_timewait6_sock(struct seq_file
*seq
,
1776 struct inet_timewait_sock
*tw
, int i
)
1778 long delta
= tw
->tw_timer
.expires
- jiffies
;
1779 const struct in6_addr
*dest
, *src
;
1782 dest
= &tw
->tw_v6_daddr
;
1783 src
= &tw
->tw_v6_rcv_saddr
;
1784 destp
= ntohs(tw
->tw_dport
);
1785 srcp
= ntohs(tw
->tw_sport
);
1788 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1789 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
1791 src
->s6_addr32
[0], src
->s6_addr32
[1],
1792 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1793 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1794 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1795 tw
->tw_substate
, 0, 0,
1796 3, jiffies_delta_to_clock_t(delta
), 0, 0, 0, 0,
1797 atomic_read(&tw
->tw_refcnt
), tw
);
1800 static int tcp6_seq_show(struct seq_file
*seq
, void *v
)
1802 struct tcp_iter_state
*st
;
1803 struct sock
*sk
= v
;
1805 if (v
== SEQ_START_TOKEN
) {
1810 "st tx_queue rx_queue tr tm->when retrnsmt"
1811 " uid timeout inode\n");
1816 if (sk
->sk_state
== TCP_TIME_WAIT
)
1817 get_timewait6_sock(seq
, v
, st
->num
);
1818 else if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
1819 get_openreq6(seq
, v
, st
->num
);
1821 get_tcp6_sock(seq
, v
, st
->num
);
1826 static const struct file_operations tcp6_afinfo_seq_fops
= {
1827 .owner
= THIS_MODULE
,
1828 .open
= tcp_seq_open
,
1830 .llseek
= seq_lseek
,
1831 .release
= seq_release_net
1834 static struct tcp_seq_afinfo tcp6_seq_afinfo
= {
1837 .seq_fops
= &tcp6_afinfo_seq_fops
,
1839 .show
= tcp6_seq_show
,
1843 int __net_init
tcp6_proc_init(struct net
*net
)
1845 return tcp_proc_register(net
, &tcp6_seq_afinfo
);
1848 void tcp6_proc_exit(struct net
*net
)
1850 tcp_proc_unregister(net
, &tcp6_seq_afinfo
);
1854 static void tcp_v6_clear_sk(struct sock
*sk
, int size
)
1856 struct inet_sock
*inet
= inet_sk(sk
);
1858 /* we do not want to clear pinet6 field, because of RCU lookups */
1859 sk_prot_clear_nulls(sk
, offsetof(struct inet_sock
, pinet6
));
1861 size
-= offsetof(struct inet_sock
, pinet6
) + sizeof(inet
->pinet6
);
1862 memset(&inet
->pinet6
+ 1, 0, size
);
1865 struct proto tcpv6_prot
= {
1867 .owner
= THIS_MODULE
,
1869 .connect
= tcp_v6_connect
,
1870 .disconnect
= tcp_disconnect
,
1871 .accept
= inet_csk_accept
,
1873 .init
= tcp_v6_init_sock
,
1874 .destroy
= tcp_v6_destroy_sock
,
1875 .shutdown
= tcp_shutdown
,
1876 .setsockopt
= tcp_setsockopt
,
1877 .getsockopt
= tcp_getsockopt
,
1878 .recvmsg
= tcp_recvmsg
,
1879 .sendmsg
= tcp_sendmsg
,
1880 .sendpage
= tcp_sendpage
,
1881 .backlog_rcv
= tcp_v6_do_rcv
,
1882 .release_cb
= tcp_release_cb
,
1884 .unhash
= inet_unhash
,
1885 .get_port
= inet_csk_get_port
,
1886 .enter_memory_pressure
= tcp_enter_memory_pressure
,
1887 .stream_memory_free
= tcp_stream_memory_free
,
1888 .sockets_allocated
= &tcp_sockets_allocated
,
1889 .memory_allocated
= &tcp_memory_allocated
,
1890 .memory_pressure
= &tcp_memory_pressure
,
1891 .orphan_count
= &tcp_orphan_count
,
1892 .sysctl_mem
= sysctl_tcp_mem
,
1893 .sysctl_wmem
= sysctl_tcp_wmem
,
1894 .sysctl_rmem
= sysctl_tcp_rmem
,
1895 .max_header
= MAX_TCP_HEADER
,
1896 .obj_size
= sizeof(struct tcp6_sock
),
1897 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1898 .twsk_prot
= &tcp6_timewait_sock_ops
,
1899 .rsk_prot
= &tcp6_request_sock_ops
,
1900 .h
.hashinfo
= &tcp_hashinfo
,
1901 .no_autobind
= true,
1902 #ifdef CONFIG_COMPAT
1903 .compat_setsockopt
= compat_tcp_setsockopt
,
1904 .compat_getsockopt
= compat_tcp_getsockopt
,
1906 .clear_sk
= tcp_v6_clear_sk
,
1907 .diag_destroy
= tcp_abort
,
1910 static const struct inet6_protocol tcpv6_protocol
= {
1911 .early_demux
= tcp_v6_early_demux
,
1912 .handler
= tcp_v6_rcv
,
1913 .err_handler
= tcp_v6_err
,
1914 .flags
= INET6_PROTO_NOPOLICY
|INET6_PROTO_FINAL
,
1917 static struct inet_protosw tcpv6_protosw
= {
1918 .type
= SOCK_STREAM
,
1919 .protocol
= IPPROTO_TCP
,
1920 .prot
= &tcpv6_prot
,
1921 .ops
= &inet6_stream_ops
,
1922 .flags
= INET_PROTOSW_PERMANENT
|
1926 static int __net_init
tcpv6_net_init(struct net
*net
)
1928 return inet_ctl_sock_create(&net
->ipv6
.tcp_sk
, PF_INET6
,
1929 SOCK_RAW
, IPPROTO_TCP
, net
);
1932 static void __net_exit
tcpv6_net_exit(struct net
*net
)
1934 inet_ctl_sock_destroy(net
->ipv6
.tcp_sk
);
1937 static void __net_exit
tcpv6_net_exit_batch(struct list_head
*net_exit_list
)
1939 inet_twsk_purge(&tcp_hashinfo
, &tcp_death_row
, AF_INET6
);
1942 static struct pernet_operations tcpv6_net_ops
= {
1943 .init
= tcpv6_net_init
,
1944 .exit
= tcpv6_net_exit
,
1945 .exit_batch
= tcpv6_net_exit_batch
,
1948 int __init
tcpv6_init(void)
1952 ret
= inet6_add_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1956 /* register inet6 protocol */
1957 ret
= inet6_register_protosw(&tcpv6_protosw
);
1959 goto out_tcpv6_protocol
;
1961 ret
= register_pernet_subsys(&tcpv6_net_ops
);
1963 goto out_tcpv6_protosw
;
1968 inet6_unregister_protosw(&tcpv6_protosw
);
1970 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1974 void tcpv6_exit(void)
1976 unregister_pernet_subsys(&tcpv6_net_ops
);
1977 inet6_unregister_protosw(&tcpv6_protosw
);
1978 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);