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>
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/netdma.h>
63 #include <net/inet_common.h>
64 #include <net/secure_seq.h>
65 #include <net/tcp_memcontrol.h>
67 #include <asm/uaccess.h>
69 #include <linux/proc_fs.h>
70 #include <linux/seq_file.h>
72 #include <linux/crypto.h>
73 #include <linux/scatterlist.h>
75 static void tcp_v6_send_reset(struct sock
*sk
, struct sk_buff
*skb
);
76 static void tcp_v6_reqsk_send_ack(struct sock
*sk
, struct sk_buff
*skb
,
77 struct request_sock
*req
);
79 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
);
81 static const struct inet_connection_sock_af_ops ipv6_mapped
;
82 static const struct inet_connection_sock_af_ops ipv6_specific
;
83 #ifdef CONFIG_TCP_MD5SIG
84 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
;
85 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
;
87 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(struct sock
*sk
,
88 const struct in6_addr
*addr
)
94 static void inet6_sk_rx_dst_set(struct sock
*sk
, const struct sk_buff
*skb
)
96 struct dst_entry
*dst
= skb_dst(skb
);
97 const struct rt6_info
*rt
= (const struct rt6_info
*)dst
;
101 inet_sk(sk
)->rx_dst_ifindex
= skb
->skb_iif
;
103 inet6_sk(sk
)->rx_dst_cookie
= rt
->rt6i_node
->fn_sernum
;
106 static void tcp_v6_hash(struct sock
*sk
)
108 if (sk
->sk_state
!= TCP_CLOSE
) {
109 if (inet_csk(sk
)->icsk_af_ops
== &ipv6_mapped
) {
114 __inet6_hash(sk
, NULL
);
119 static __u32
tcp_v6_init_sequence(const struct sk_buff
*skb
)
121 return secure_tcpv6_sequence_number(ipv6_hdr(skb
)->daddr
.s6_addr32
,
122 ipv6_hdr(skb
)->saddr
.s6_addr32
,
124 tcp_hdr(skb
)->source
);
127 static int tcp_v6_connect(struct sock
*sk
, struct sockaddr
*uaddr
,
130 struct sockaddr_in6
*usin
= (struct sockaddr_in6
*) uaddr
;
131 struct inet_sock
*inet
= inet_sk(sk
);
132 struct inet_connection_sock
*icsk
= inet_csk(sk
);
133 struct ipv6_pinfo
*np
= inet6_sk(sk
);
134 struct tcp_sock
*tp
= tcp_sk(sk
);
135 struct in6_addr
*saddr
= NULL
, *final_p
, final
;
138 struct dst_entry
*dst
;
142 if (addr_len
< SIN6_LEN_RFC2133
)
145 if (usin
->sin6_family
!= AF_INET6
)
146 return -EAFNOSUPPORT
;
148 memset(&fl6
, 0, sizeof(fl6
));
151 fl6
.flowlabel
= usin
->sin6_flowinfo
&IPV6_FLOWINFO_MASK
;
152 IP6_ECN_flow_init(fl6
.flowlabel
);
153 if (fl6
.flowlabel
&IPV6_FLOWLABEL_MASK
) {
154 struct ip6_flowlabel
*flowlabel
;
155 flowlabel
= fl6_sock_lookup(sk
, fl6
.flowlabel
);
156 if (flowlabel
== NULL
)
158 usin
->sin6_addr
= flowlabel
->dst
;
159 fl6_sock_release(flowlabel
);
164 * connect() to INADDR_ANY means loopback (BSD'ism).
167 if(ipv6_addr_any(&usin
->sin6_addr
))
168 usin
->sin6_addr
.s6_addr
[15] = 0x1;
170 addr_type
= ipv6_addr_type(&usin
->sin6_addr
);
172 if(addr_type
& IPV6_ADDR_MULTICAST
)
175 if (addr_type
&IPV6_ADDR_LINKLOCAL
) {
176 if (addr_len
>= sizeof(struct sockaddr_in6
) &&
177 usin
->sin6_scope_id
) {
178 /* If interface is set while binding, indices
181 if (sk
->sk_bound_dev_if
&&
182 sk
->sk_bound_dev_if
!= usin
->sin6_scope_id
)
185 sk
->sk_bound_dev_if
= usin
->sin6_scope_id
;
188 /* Connect to link-local address requires an interface */
189 if (!sk
->sk_bound_dev_if
)
193 if (tp
->rx_opt
.ts_recent_stamp
&&
194 !ipv6_addr_equal(&np
->daddr
, &usin
->sin6_addr
)) {
195 tp
->rx_opt
.ts_recent
= 0;
196 tp
->rx_opt
.ts_recent_stamp
= 0;
200 np
->daddr
= usin
->sin6_addr
;
201 np
->flow_label
= fl6
.flowlabel
;
207 if (addr_type
== IPV6_ADDR_MAPPED
) {
208 u32 exthdrlen
= icsk
->icsk_ext_hdr_len
;
209 struct sockaddr_in sin
;
211 SOCK_DEBUG(sk
, "connect: ipv4 mapped\n");
213 if (__ipv6_only_sock(sk
))
216 sin
.sin_family
= AF_INET
;
217 sin
.sin_port
= usin
->sin6_port
;
218 sin
.sin_addr
.s_addr
= usin
->sin6_addr
.s6_addr32
[3];
220 icsk
->icsk_af_ops
= &ipv6_mapped
;
221 sk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
222 #ifdef CONFIG_TCP_MD5SIG
223 tp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
226 err
= tcp_v4_connect(sk
, (struct sockaddr
*)&sin
, sizeof(sin
));
229 icsk
->icsk_ext_hdr_len
= exthdrlen
;
230 icsk
->icsk_af_ops
= &ipv6_specific
;
231 sk
->sk_backlog_rcv
= tcp_v6_do_rcv
;
232 #ifdef CONFIG_TCP_MD5SIG
233 tp
->af_specific
= &tcp_sock_ipv6_specific
;
237 ipv6_addr_set_v4mapped(inet
->inet_saddr
, &np
->saddr
);
238 ipv6_addr_set_v4mapped(inet
->inet_rcv_saddr
,
245 if (!ipv6_addr_any(&np
->rcv_saddr
))
246 saddr
= &np
->rcv_saddr
;
248 fl6
.flowi6_proto
= IPPROTO_TCP
;
249 fl6
.daddr
= np
->daddr
;
250 fl6
.saddr
= saddr
? *saddr
: np
->saddr
;
251 fl6
.flowi6_oif
= sk
->sk_bound_dev_if
;
252 fl6
.flowi6_mark
= sk
->sk_mark
;
253 fl6
.fl6_dport
= usin
->sin6_port
;
254 fl6
.fl6_sport
= inet
->inet_sport
;
256 final_p
= fl6_update_dst(&fl6
, np
->opt
, &final
);
258 security_sk_classify_flow(sk
, flowi6_to_flowi(&fl6
));
260 dst
= ip6_dst_lookup_flow(sk
, &fl6
, final_p
, true);
268 np
->rcv_saddr
= *saddr
;
271 /* set the source address */
273 inet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
275 sk
->sk_gso_type
= SKB_GSO_TCPV6
;
276 __ip6_dst_store(sk
, dst
, NULL
, NULL
);
278 rt
= (struct rt6_info
*) dst
;
279 if (tcp_death_row
.sysctl_tw_recycle
&&
280 !tp
->rx_opt
.ts_recent_stamp
&&
281 ipv6_addr_equal(&rt
->rt6i_dst
.addr
, &np
->daddr
))
282 tcp_fetch_timewait_stamp(sk
, dst
);
284 icsk
->icsk_ext_hdr_len
= 0;
286 icsk
->icsk_ext_hdr_len
= (np
->opt
->opt_flen
+
289 tp
->rx_opt
.mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) - sizeof(struct ipv6hdr
);
291 inet
->inet_dport
= usin
->sin6_port
;
293 tcp_set_state(sk
, TCP_SYN_SENT
);
294 err
= inet6_hash_connect(&tcp_death_row
, sk
);
298 if (!tp
->write_seq
&& likely(!tp
->repair
))
299 tp
->write_seq
= secure_tcpv6_sequence_number(np
->saddr
.s6_addr32
,
304 err
= tcp_connect(sk
);
311 tcp_set_state(sk
, TCP_CLOSE
);
314 inet
->inet_dport
= 0;
315 sk
->sk_route_caps
= 0;
319 static void tcp_v6_mtu_reduced(struct sock
*sk
)
321 struct dst_entry
*dst
;
323 if ((1 << sk
->sk_state
) & (TCPF_LISTEN
| TCPF_CLOSE
))
326 dst
= inet6_csk_update_pmtu(sk
, tcp_sk(sk
)->mtu_info
);
330 if (inet_csk(sk
)->icsk_pmtu_cookie
> dst_mtu(dst
)) {
331 tcp_sync_mss(sk
, dst_mtu(dst
));
332 tcp_simple_retransmit(sk
);
336 static void tcp_v6_err(struct sk_buff
*skb
, struct inet6_skb_parm
*opt
,
337 u8 type
, u8 code
, int offset
, __be32 info
)
339 const struct ipv6hdr
*hdr
= (const struct ipv6hdr
*)skb
->data
;
340 const struct tcphdr
*th
= (struct tcphdr
*)(skb
->data
+offset
);
341 struct ipv6_pinfo
*np
;
346 struct net
*net
= dev_net(skb
->dev
);
348 sk
= inet6_lookup(net
, &tcp_hashinfo
, &hdr
->daddr
,
349 th
->dest
, &hdr
->saddr
, th
->source
, skb
->dev
->ifindex
);
352 ICMP6_INC_STATS_BH(net
, __in6_dev_get(skb
->dev
),
357 if (sk
->sk_state
== TCP_TIME_WAIT
) {
358 inet_twsk_put(inet_twsk(sk
));
363 if (sock_owned_by_user(sk
) && type
!= ICMPV6_PKT_TOOBIG
)
364 NET_INC_STATS_BH(net
, LINUX_MIB_LOCKDROPPEDICMPS
);
366 if (sk
->sk_state
== TCP_CLOSE
)
369 if (ipv6_hdr(skb
)->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
370 NET_INC_STATS_BH(net
, LINUX_MIB_TCPMINTTLDROP
);
375 seq
= ntohl(th
->seq
);
376 if (sk
->sk_state
!= TCP_LISTEN
&&
377 !between(seq
, tp
->snd_una
, tp
->snd_nxt
)) {
378 NET_INC_STATS_BH(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
384 if (type
== NDISC_REDIRECT
) {
385 struct dst_entry
*dst
= __sk_dst_check(sk
, np
->dst_cookie
);
388 dst
->ops
->redirect(dst
, sk
, skb
);
391 if (type
== ICMPV6_PKT_TOOBIG
) {
392 tp
->mtu_info
= ntohl(info
);
393 if (!sock_owned_by_user(sk
))
394 tcp_v6_mtu_reduced(sk
);
395 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED
,
401 icmpv6_err_convert(type
, code
, &err
);
403 /* Might be for an request_sock */
404 switch (sk
->sk_state
) {
405 struct request_sock
*req
, **prev
;
407 if (sock_owned_by_user(sk
))
410 req
= inet6_csk_search_req(sk
, &prev
, th
->dest
, &hdr
->daddr
,
411 &hdr
->saddr
, inet6_iif(skb
));
415 /* ICMPs are not backlogged, hence we cannot get
416 * an established socket here.
418 WARN_ON(req
->sk
!= NULL
);
420 if (seq
!= tcp_rsk(req
)->snt_isn
) {
421 NET_INC_STATS_BH(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
425 inet_csk_reqsk_queue_drop(sk
, req
, prev
);
429 case TCP_SYN_RECV
: /* Cannot happen.
430 It can, it SYNs are crossed. --ANK */
431 if (!sock_owned_by_user(sk
)) {
433 sk
->sk_error_report(sk
); /* Wake people up to see the error (see connect in sock.c) */
437 sk
->sk_err_soft
= err
;
441 if (!sock_owned_by_user(sk
) && np
->recverr
) {
443 sk
->sk_error_report(sk
);
445 sk
->sk_err_soft
= err
;
453 static int tcp_v6_send_synack(struct sock
*sk
, struct dst_entry
*dst
,
455 struct request_sock
*req
,
456 struct request_values
*rvp
,
459 struct inet6_request_sock
*treq
= inet6_rsk(req
);
460 struct ipv6_pinfo
*np
= inet6_sk(sk
);
461 struct sk_buff
* skb
;
464 /* First, grab a route. */
465 if (!dst
&& (dst
= inet6_csk_route_req(sk
, fl6
, req
)) == NULL
)
468 skb
= tcp_make_synack(sk
, dst
, req
, rvp
, NULL
);
471 __tcp_v6_send_check(skb
, &treq
->loc_addr
, &treq
->rmt_addr
);
473 fl6
->daddr
= treq
->rmt_addr
;
474 skb_set_queue_mapping(skb
, queue_mapping
);
475 err
= ip6_xmit(sk
, skb
, fl6
, np
->opt
, np
->tclass
);
476 err
= net_xmit_eval(err
);
483 static int tcp_v6_rtx_synack(struct sock
*sk
, struct request_sock
*req
,
484 struct request_values
*rvp
)
489 res
= tcp_v6_send_synack(sk
, NULL
, &fl6
, req
, rvp
, 0);
491 TCP_INC_STATS_BH(sock_net(sk
), TCP_MIB_RETRANSSEGS
);
495 static void tcp_v6_reqsk_destructor(struct request_sock
*req
)
497 kfree_skb(inet6_rsk(req
)->pktopts
);
500 #ifdef CONFIG_TCP_MD5SIG
501 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(struct sock
*sk
,
502 const struct in6_addr
*addr
)
504 return tcp_md5_do_lookup(sk
, (union tcp_md5_addr
*)addr
, AF_INET6
);
507 static struct tcp_md5sig_key
*tcp_v6_md5_lookup(struct sock
*sk
,
508 struct sock
*addr_sk
)
510 return tcp_v6_md5_do_lookup(sk
, &inet6_sk(addr_sk
)->daddr
);
513 static struct tcp_md5sig_key
*tcp_v6_reqsk_md5_lookup(struct sock
*sk
,
514 struct request_sock
*req
)
516 return tcp_v6_md5_do_lookup(sk
, &inet6_rsk(req
)->rmt_addr
);
519 static int tcp_v6_parse_md5_keys (struct sock
*sk
, char __user
*optval
,
522 struct tcp_md5sig cmd
;
523 struct sockaddr_in6
*sin6
= (struct sockaddr_in6
*)&cmd
.tcpm_addr
;
525 if (optlen
< sizeof(cmd
))
528 if (copy_from_user(&cmd
, optval
, sizeof(cmd
)))
531 if (sin6
->sin6_family
!= AF_INET6
)
534 if (!cmd
.tcpm_keylen
) {
535 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
536 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
538 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
542 if (cmd
.tcpm_keylen
> TCP_MD5SIG_MAXKEYLEN
)
545 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
546 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
547 AF_INET
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
549 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
550 AF_INET6
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
553 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool
*hp
,
554 const struct in6_addr
*daddr
,
555 const struct in6_addr
*saddr
, int nbytes
)
557 struct tcp6_pseudohdr
*bp
;
558 struct scatterlist sg
;
560 bp
= &hp
->md5_blk
.ip6
;
561 /* 1. TCP pseudo-header (RFC2460) */
564 bp
->protocol
= cpu_to_be32(IPPROTO_TCP
);
565 bp
->len
= cpu_to_be32(nbytes
);
567 sg_init_one(&sg
, bp
, sizeof(*bp
));
568 return crypto_hash_update(&hp
->md5_desc
, &sg
, sizeof(*bp
));
571 static int tcp_v6_md5_hash_hdr(char *md5_hash
, struct tcp_md5sig_key
*key
,
572 const struct in6_addr
*daddr
, struct in6_addr
*saddr
,
573 const struct tcphdr
*th
)
575 struct tcp_md5sig_pool
*hp
;
576 struct hash_desc
*desc
;
578 hp
= tcp_get_md5sig_pool();
580 goto clear_hash_noput
;
581 desc
= &hp
->md5_desc
;
583 if (crypto_hash_init(desc
))
585 if (tcp_v6_md5_hash_pseudoheader(hp
, daddr
, saddr
, th
->doff
<< 2))
587 if (tcp_md5_hash_header(hp
, th
))
589 if (tcp_md5_hash_key(hp
, key
))
591 if (crypto_hash_final(desc
, md5_hash
))
594 tcp_put_md5sig_pool();
598 tcp_put_md5sig_pool();
600 memset(md5_hash
, 0, 16);
604 static int tcp_v6_md5_hash_skb(char *md5_hash
, struct tcp_md5sig_key
*key
,
605 const struct sock
*sk
,
606 const struct request_sock
*req
,
607 const struct sk_buff
*skb
)
609 const struct in6_addr
*saddr
, *daddr
;
610 struct tcp_md5sig_pool
*hp
;
611 struct hash_desc
*desc
;
612 const struct tcphdr
*th
= tcp_hdr(skb
);
615 saddr
= &inet6_sk(sk
)->saddr
;
616 daddr
= &inet6_sk(sk
)->daddr
;
618 saddr
= &inet6_rsk(req
)->loc_addr
;
619 daddr
= &inet6_rsk(req
)->rmt_addr
;
621 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
622 saddr
= &ip6h
->saddr
;
623 daddr
= &ip6h
->daddr
;
626 hp
= tcp_get_md5sig_pool();
628 goto clear_hash_noput
;
629 desc
= &hp
->md5_desc
;
631 if (crypto_hash_init(desc
))
634 if (tcp_v6_md5_hash_pseudoheader(hp
, daddr
, saddr
, skb
->len
))
636 if (tcp_md5_hash_header(hp
, th
))
638 if (tcp_md5_hash_skb_data(hp
, skb
, th
->doff
<< 2))
640 if (tcp_md5_hash_key(hp
, key
))
642 if (crypto_hash_final(desc
, md5_hash
))
645 tcp_put_md5sig_pool();
649 tcp_put_md5sig_pool();
651 memset(md5_hash
, 0, 16);
655 static int tcp_v6_inbound_md5_hash(struct sock
*sk
, const struct sk_buff
*skb
)
657 const __u8
*hash_location
= NULL
;
658 struct tcp_md5sig_key
*hash_expected
;
659 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
660 const struct tcphdr
*th
= tcp_hdr(skb
);
664 hash_expected
= tcp_v6_md5_do_lookup(sk
, &ip6h
->saddr
);
665 hash_location
= tcp_parse_md5sig_option(th
);
667 /* We've parsed the options - do we have a hash? */
668 if (!hash_expected
&& !hash_location
)
671 if (hash_expected
&& !hash_location
) {
672 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_TCPMD5NOTFOUND
);
676 if (!hash_expected
&& hash_location
) {
677 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_TCPMD5UNEXPECTED
);
681 /* check the signature */
682 genhash
= tcp_v6_md5_hash_skb(newhash
,
686 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0) {
687 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
688 genhash
? "failed" : "mismatch",
689 &ip6h
->saddr
, ntohs(th
->source
),
690 &ip6h
->daddr
, ntohs(th
->dest
));
697 struct request_sock_ops tcp6_request_sock_ops __read_mostly
= {
699 .obj_size
= sizeof(struct tcp6_request_sock
),
700 .rtx_syn_ack
= tcp_v6_rtx_synack
,
701 .send_ack
= tcp_v6_reqsk_send_ack
,
702 .destructor
= tcp_v6_reqsk_destructor
,
703 .send_reset
= tcp_v6_send_reset
,
704 .syn_ack_timeout
= tcp_syn_ack_timeout
,
707 #ifdef CONFIG_TCP_MD5SIG
708 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops
= {
709 .md5_lookup
= tcp_v6_reqsk_md5_lookup
,
710 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
714 static void tcp_v6_send_response(struct sk_buff
*skb
, u32 seq
, u32 ack
, u32 win
,
715 u32 ts
, struct tcp_md5sig_key
*key
, int rst
, u8 tclass
)
717 const struct tcphdr
*th
= tcp_hdr(skb
);
719 struct sk_buff
*buff
;
721 struct net
*net
= dev_net(skb_dst(skb
)->dev
);
722 struct sock
*ctl_sk
= net
->ipv6
.tcp_sk
;
723 unsigned int tot_len
= sizeof(struct tcphdr
);
724 struct dst_entry
*dst
;
728 tot_len
+= TCPOLEN_TSTAMP_ALIGNED
;
729 #ifdef CONFIG_TCP_MD5SIG
731 tot_len
+= TCPOLEN_MD5SIG_ALIGNED
;
734 buff
= alloc_skb(MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
,
739 skb_reserve(buff
, MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
);
741 t1
= (struct tcphdr
*) skb_push(buff
, tot_len
);
742 skb_reset_transport_header(buff
);
744 /* Swap the send and the receive. */
745 memset(t1
, 0, sizeof(*t1
));
746 t1
->dest
= th
->source
;
747 t1
->source
= th
->dest
;
748 t1
->doff
= tot_len
/ 4;
749 t1
->seq
= htonl(seq
);
750 t1
->ack_seq
= htonl(ack
);
751 t1
->ack
= !rst
|| !th
->ack
;
753 t1
->window
= htons(win
);
755 topt
= (__be32
*)(t1
+ 1);
758 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
759 (TCPOPT_TIMESTAMP
<< 8) | TCPOLEN_TIMESTAMP
);
760 *topt
++ = htonl(tcp_time_stamp
);
764 #ifdef CONFIG_TCP_MD5SIG
766 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
767 (TCPOPT_MD5SIG
<< 8) | TCPOLEN_MD5SIG
);
768 tcp_v6_md5_hash_hdr((__u8
*)topt
, key
,
769 &ipv6_hdr(skb
)->saddr
,
770 &ipv6_hdr(skb
)->daddr
, t1
);
774 memset(&fl6
, 0, sizeof(fl6
));
775 fl6
.daddr
= ipv6_hdr(skb
)->saddr
;
776 fl6
.saddr
= ipv6_hdr(skb
)->daddr
;
778 buff
->ip_summed
= CHECKSUM_PARTIAL
;
781 __tcp_v6_send_check(buff
, &fl6
.saddr
, &fl6
.daddr
);
783 fl6
.flowi6_proto
= IPPROTO_TCP
;
784 if (ipv6_addr_type(&fl6
.daddr
) & IPV6_ADDR_LINKLOCAL
)
785 fl6
.flowi6_oif
= inet6_iif(skb
);
786 fl6
.fl6_dport
= t1
->dest
;
787 fl6
.fl6_sport
= t1
->source
;
788 security_skb_classify_flow(skb
, flowi6_to_flowi(&fl6
));
790 /* Pass a socket to ip6_dst_lookup either it is for RST
791 * Underlying function will use this to retrieve the network
794 dst
= ip6_dst_lookup_flow(ctl_sk
, &fl6
, NULL
, false);
796 skb_dst_set(buff
, dst
);
797 ip6_xmit(ctl_sk
, buff
, &fl6
, NULL
, tclass
);
798 TCP_INC_STATS_BH(net
, TCP_MIB_OUTSEGS
);
800 TCP_INC_STATS_BH(net
, TCP_MIB_OUTRSTS
);
807 static void tcp_v6_send_reset(struct sock
*sk
, struct sk_buff
*skb
)
809 const struct tcphdr
*th
= tcp_hdr(skb
);
810 u32 seq
= 0, ack_seq
= 0;
811 struct tcp_md5sig_key
*key
= NULL
;
812 #ifdef CONFIG_TCP_MD5SIG
813 const __u8
*hash_location
= NULL
;
814 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
815 unsigned char newhash
[16];
817 struct sock
*sk1
= NULL
;
823 if (!ipv6_unicast_destination(skb
))
826 #ifdef CONFIG_TCP_MD5SIG
827 hash_location
= tcp_parse_md5sig_option(th
);
828 if (!sk
&& hash_location
) {
830 * active side is lost. Try to find listening socket through
831 * source port, and then find md5 key through listening socket.
832 * we are not loose security here:
833 * Incoming packet is checked with md5 hash with finding key,
834 * no RST generated if md5 hash doesn't match.
836 sk1
= inet6_lookup_listener(dev_net(skb_dst(skb
)->dev
),
837 &tcp_hashinfo
, &ipv6h
->daddr
,
838 ntohs(th
->source
), inet6_iif(skb
));
843 key
= tcp_v6_md5_do_lookup(sk1
, &ipv6h
->saddr
);
847 genhash
= tcp_v6_md5_hash_skb(newhash
, key
, NULL
, NULL
, skb
);
848 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0)
851 key
= sk
? tcp_v6_md5_do_lookup(sk
, &ipv6h
->saddr
) : NULL
;
856 seq
= ntohl(th
->ack_seq
);
858 ack_seq
= ntohl(th
->seq
) + th
->syn
+ th
->fin
+ skb
->len
-
861 tcp_v6_send_response(skb
, seq
, ack_seq
, 0, 0, key
, 1, 0);
863 #ifdef CONFIG_TCP_MD5SIG
872 static void tcp_v6_send_ack(struct sk_buff
*skb
, u32 seq
, u32 ack
, u32 win
, u32 ts
,
873 struct tcp_md5sig_key
*key
, u8 tclass
)
875 tcp_v6_send_response(skb
, seq
, ack
, win
, ts
, key
, 0, tclass
);
878 static void tcp_v6_timewait_ack(struct sock
*sk
, struct sk_buff
*skb
)
880 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
881 struct tcp_timewait_sock
*tcptw
= tcp_twsk(sk
);
883 tcp_v6_send_ack(skb
, tcptw
->tw_snd_nxt
, tcptw
->tw_rcv_nxt
,
884 tcptw
->tw_rcv_wnd
>> tw
->tw_rcv_wscale
,
885 tcptw
->tw_ts_recent
, tcp_twsk_md5_key(tcptw
),
891 static void tcp_v6_reqsk_send_ack(struct sock
*sk
, struct sk_buff
*skb
,
892 struct request_sock
*req
)
894 tcp_v6_send_ack(skb
, tcp_rsk(req
)->snt_isn
+ 1, tcp_rsk(req
)->rcv_isn
+ 1, req
->rcv_wnd
, req
->ts_recent
,
895 tcp_v6_md5_do_lookup(sk
, &ipv6_hdr(skb
)->daddr
), 0);
899 static struct sock
*tcp_v6_hnd_req(struct sock
*sk
,struct sk_buff
*skb
)
901 struct request_sock
*req
, **prev
;
902 const struct tcphdr
*th
= tcp_hdr(skb
);
905 /* Find possible connection requests. */
906 req
= inet6_csk_search_req(sk
, &prev
, th
->source
,
907 &ipv6_hdr(skb
)->saddr
,
908 &ipv6_hdr(skb
)->daddr
, inet6_iif(skb
));
910 return tcp_check_req(sk
, skb
, req
, prev
, false);
912 nsk
= __inet6_lookup_established(sock_net(sk
), &tcp_hashinfo
,
913 &ipv6_hdr(skb
)->saddr
, th
->source
,
914 &ipv6_hdr(skb
)->daddr
, ntohs(th
->dest
), inet6_iif(skb
));
917 if (nsk
->sk_state
!= TCP_TIME_WAIT
) {
921 inet_twsk_put(inet_twsk(nsk
));
925 #ifdef CONFIG_SYN_COOKIES
927 sk
= cookie_v6_check(sk
, skb
);
932 /* FIXME: this is substantially similar to the ipv4 code.
933 * Can some kind of merge be done? -- erics
935 static int tcp_v6_conn_request(struct sock
*sk
, struct sk_buff
*skb
)
937 struct tcp_extend_values tmp_ext
;
938 struct tcp_options_received tmp_opt
;
939 const u8
*hash_location
;
940 struct request_sock
*req
;
941 struct inet6_request_sock
*treq
;
942 struct ipv6_pinfo
*np
= inet6_sk(sk
);
943 struct tcp_sock
*tp
= tcp_sk(sk
);
944 __u32 isn
= TCP_SKB_CB(skb
)->when
;
945 struct dst_entry
*dst
= NULL
;
947 bool want_cookie
= false;
949 if (skb
->protocol
== htons(ETH_P_IP
))
950 return tcp_v4_conn_request(sk
, skb
);
952 if (!ipv6_unicast_destination(skb
))
955 if (inet_csk_reqsk_queue_is_full(sk
) && !isn
) {
956 want_cookie
= tcp_syn_flood_action(sk
, skb
, "TCPv6");
961 if (sk_acceptq_is_full(sk
) && inet_csk_reqsk_queue_young(sk
) > 1)
964 req
= inet6_reqsk_alloc(&tcp6_request_sock_ops
);
968 #ifdef CONFIG_TCP_MD5SIG
969 tcp_rsk(req
)->af_specific
= &tcp_request_sock_ipv6_ops
;
972 tcp_clear_options(&tmp_opt
);
973 tmp_opt
.mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) - sizeof(struct ipv6hdr
);
974 tmp_opt
.user_mss
= tp
->rx_opt
.user_mss
;
975 tcp_parse_options(skb
, &tmp_opt
, &hash_location
, 0, NULL
);
977 if (tmp_opt
.cookie_plus
> 0 &&
978 tmp_opt
.saw_tstamp
&&
979 !tp
->rx_opt
.cookie_out_never
&&
980 (sysctl_tcp_cookie_size
> 0 ||
981 (tp
->cookie_values
!= NULL
&&
982 tp
->cookie_values
->cookie_desired
> 0))) {
985 u32
*mess
= &tmp_ext
.cookie_bakery
[COOKIE_DIGEST_WORDS
];
986 int l
= tmp_opt
.cookie_plus
- TCPOLEN_COOKIE_BASE
;
988 if (tcp_cookie_generator(&tmp_ext
.cookie_bakery
[0]) != 0)
991 /* Secret recipe starts with IP addresses */
992 d
= (__force u32
*)&ipv6_hdr(skb
)->daddr
.s6_addr32
[0];
997 d
= (__force u32
*)&ipv6_hdr(skb
)->saddr
.s6_addr32
[0];
1003 /* plus variable length Initiator Cookie */
1006 *c
++ ^= *hash_location
++;
1008 want_cookie
= false; /* not our kind of cookie */
1009 tmp_ext
.cookie_out_never
= 0; /* false */
1010 tmp_ext
.cookie_plus
= tmp_opt
.cookie_plus
;
1011 } else if (!tp
->rx_opt
.cookie_in_always
) {
1012 /* redundant indications, but ensure initialization. */
1013 tmp_ext
.cookie_out_never
= 1; /* true */
1014 tmp_ext
.cookie_plus
= 0;
1018 tmp_ext
.cookie_in_always
= tp
->rx_opt
.cookie_in_always
;
1020 if (want_cookie
&& !tmp_opt
.saw_tstamp
)
1021 tcp_clear_options(&tmp_opt
);
1023 tmp_opt
.tstamp_ok
= tmp_opt
.saw_tstamp
;
1024 tcp_openreq_init(req
, &tmp_opt
, skb
);
1026 treq
= inet6_rsk(req
);
1027 treq
->rmt_addr
= ipv6_hdr(skb
)->saddr
;
1028 treq
->loc_addr
= ipv6_hdr(skb
)->daddr
;
1029 if (!want_cookie
|| tmp_opt
.tstamp_ok
)
1030 TCP_ECN_create_request(req
, skb
);
1032 treq
->iif
= sk
->sk_bound_dev_if
;
1034 /* So that link locals have meaning */
1035 if (!sk
->sk_bound_dev_if
&&
1036 ipv6_addr_type(&treq
->rmt_addr
) & IPV6_ADDR_LINKLOCAL
)
1037 treq
->iif
= inet6_iif(skb
);
1040 if (ipv6_opt_accepted(sk
, skb
) ||
1041 np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
||
1042 np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
) {
1043 atomic_inc(&skb
->users
);
1044 treq
->pktopts
= skb
;
1048 isn
= cookie_v6_init_sequence(sk
, skb
, &req
->mss
);
1049 req
->cookie_ts
= tmp_opt
.tstamp_ok
;
1053 /* VJ's idea. We save last timestamp seen
1054 * from the destination in peer table, when entering
1055 * state TIME-WAIT, and check against it before
1056 * accepting new connection request.
1058 * If "isn" is not zero, this request hit alive
1059 * timewait bucket, so that all the necessary checks
1060 * are made in the function processing timewait state.
1062 if (tmp_opt
.saw_tstamp
&&
1063 tcp_death_row
.sysctl_tw_recycle
&&
1064 (dst
= inet6_csk_route_req(sk
, &fl6
, req
)) != NULL
) {
1065 if (!tcp_peer_is_proven(req
, dst
, true)) {
1066 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_PAWSPASSIVEREJECTED
);
1067 goto drop_and_release
;
1070 /* Kill the following clause, if you dislike this way. */
1071 else if (!sysctl_tcp_syncookies
&&
1072 (sysctl_max_syn_backlog
- inet_csk_reqsk_queue_len(sk
) <
1073 (sysctl_max_syn_backlog
>> 2)) &&
1074 !tcp_peer_is_proven(req
, dst
, false)) {
1075 /* Without syncookies last quarter of
1076 * backlog is filled with destinations,
1077 * proven to be alive.
1078 * It means that we continue to communicate
1079 * to destinations, already remembered
1080 * to the moment of synflood.
1082 LIMIT_NETDEBUG(KERN_DEBUG
"TCP: drop open request from %pI6/%u\n",
1083 &treq
->rmt_addr
, ntohs(tcp_hdr(skb
)->source
));
1084 goto drop_and_release
;
1087 isn
= tcp_v6_init_sequence(skb
);
1090 tcp_rsk(req
)->snt_isn
= isn
;
1092 if (security_inet_conn_request(sk
, skb
, req
))
1093 goto drop_and_release
;
1095 if (tcp_v6_send_synack(sk
, dst
, &fl6
, req
,
1096 (struct request_values
*)&tmp_ext
,
1097 skb_get_queue_mapping(skb
)) ||
1101 tcp_rsk(req
)->snt_synack
= tcp_time_stamp
;
1102 tcp_rsk(req
)->listener
= NULL
;
1103 inet6_csk_reqsk_queue_hash_add(sk
, req
, TCP_TIMEOUT_INIT
);
1111 return 0; /* don't send reset */
1114 static struct sock
* tcp_v6_syn_recv_sock(struct sock
*sk
, struct sk_buff
*skb
,
1115 struct request_sock
*req
,
1116 struct dst_entry
*dst
)
1118 struct inet6_request_sock
*treq
;
1119 struct ipv6_pinfo
*newnp
, *np
= inet6_sk(sk
);
1120 struct tcp6_sock
*newtcp6sk
;
1121 struct inet_sock
*newinet
;
1122 struct tcp_sock
*newtp
;
1124 #ifdef CONFIG_TCP_MD5SIG
1125 struct tcp_md5sig_key
*key
;
1129 if (skb
->protocol
== htons(ETH_P_IP
)) {
1134 newsk
= tcp_v4_syn_recv_sock(sk
, skb
, req
, dst
);
1139 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1140 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1142 newinet
= inet_sk(newsk
);
1143 newnp
= inet6_sk(newsk
);
1144 newtp
= tcp_sk(newsk
);
1146 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1148 ipv6_addr_set_v4mapped(newinet
->inet_daddr
, &newnp
->daddr
);
1150 ipv6_addr_set_v4mapped(newinet
->inet_saddr
, &newnp
->saddr
);
1152 newnp
->rcv_saddr
= newnp
->saddr
;
1154 inet_csk(newsk
)->icsk_af_ops
= &ipv6_mapped
;
1155 newsk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
1156 #ifdef CONFIG_TCP_MD5SIG
1157 newtp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
1160 newnp
->ipv6_ac_list
= NULL
;
1161 newnp
->ipv6_fl_list
= NULL
;
1162 newnp
->pktoptions
= NULL
;
1164 newnp
->mcast_oif
= inet6_iif(skb
);
1165 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1166 newnp
->rcv_tclass
= ipv6_tclass(ipv6_hdr(skb
));
1169 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1170 * here, tcp_create_openreq_child now does this for us, see the comment in
1171 * that function for the gory details. -acme
1174 /* It is tricky place. Until this moment IPv4 tcp
1175 worked with IPv6 icsk.icsk_af_ops.
1178 tcp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
1183 treq
= inet6_rsk(req
);
1185 if (sk_acceptq_is_full(sk
))
1189 dst
= inet6_csk_route_req(sk
, &fl6
, req
);
1194 newsk
= tcp_create_openreq_child(sk
, req
, skb
);
1199 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1200 * count here, tcp_create_openreq_child now does this for us, see the
1201 * comment in that function for the gory details. -acme
1204 newsk
->sk_gso_type
= SKB_GSO_TCPV6
;
1205 __ip6_dst_store(newsk
, dst
, NULL
, NULL
);
1206 inet6_sk_rx_dst_set(newsk
, skb
);
1208 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1209 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1211 newtp
= tcp_sk(newsk
);
1212 newinet
= inet_sk(newsk
);
1213 newnp
= inet6_sk(newsk
);
1215 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1217 newnp
->daddr
= treq
->rmt_addr
;
1218 newnp
->saddr
= treq
->loc_addr
;
1219 newnp
->rcv_saddr
= treq
->loc_addr
;
1220 newsk
->sk_bound_dev_if
= treq
->iif
;
1222 /* Now IPv6 options...
1224 First: no IPv4 options.
1226 newinet
->inet_opt
= NULL
;
1227 newnp
->ipv6_ac_list
= NULL
;
1228 newnp
->ipv6_fl_list
= NULL
;
1231 newnp
->rxopt
.all
= np
->rxopt
.all
;
1233 /* Clone pktoptions received with SYN */
1234 newnp
->pktoptions
= NULL
;
1235 if (treq
->pktopts
!= NULL
) {
1236 newnp
->pktoptions
= skb_clone(treq
->pktopts
,
1237 sk_gfp_atomic(sk
, GFP_ATOMIC
));
1238 consume_skb(treq
->pktopts
);
1239 treq
->pktopts
= NULL
;
1240 if (newnp
->pktoptions
)
1241 skb_set_owner_r(newnp
->pktoptions
, newsk
);
1244 newnp
->mcast_oif
= inet6_iif(skb
);
1245 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1246 newnp
->rcv_tclass
= ipv6_tclass(ipv6_hdr(skb
));
1248 /* Clone native IPv6 options from listening socket (if any)
1250 Yes, keeping reference count would be much more clever,
1251 but we make one more one thing there: reattach optmem
1255 newnp
->opt
= ipv6_dup_options(newsk
, np
->opt
);
1257 inet_csk(newsk
)->icsk_ext_hdr_len
= 0;
1259 inet_csk(newsk
)->icsk_ext_hdr_len
= (newnp
->opt
->opt_nflen
+
1260 newnp
->opt
->opt_flen
);
1262 tcp_mtup_init(newsk
);
1263 tcp_sync_mss(newsk
, dst_mtu(dst
));
1264 newtp
->advmss
= dst_metric_advmss(dst
);
1265 if (tcp_sk(sk
)->rx_opt
.user_mss
&&
1266 tcp_sk(sk
)->rx_opt
.user_mss
< newtp
->advmss
)
1267 newtp
->advmss
= tcp_sk(sk
)->rx_opt
.user_mss
;
1269 tcp_initialize_rcv_mss(newsk
);
1270 tcp_synack_rtt_meas(newsk
, req
);
1271 newtp
->total_retrans
= req
->num_retrans
;
1273 newinet
->inet_daddr
= newinet
->inet_saddr
= LOOPBACK4_IPV6
;
1274 newinet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
1276 #ifdef CONFIG_TCP_MD5SIG
1277 /* Copy over the MD5 key from the original socket */
1278 if ((key
= tcp_v6_md5_do_lookup(sk
, &newnp
->daddr
)) != NULL
) {
1279 /* We're using one, so create a matching key
1280 * on the newsk structure. If we fail to get
1281 * memory, then we end up not copying the key
1284 tcp_md5_do_add(newsk
, (union tcp_md5_addr
*)&newnp
->daddr
,
1285 AF_INET6
, key
->key
, key
->keylen
,
1286 sk_gfp_atomic(sk
, GFP_ATOMIC
));
1290 if (__inet_inherit_port(sk
, newsk
) < 0) {
1291 inet_csk_prepare_forced_close(newsk
);
1295 __inet6_hash(newsk
, NULL
);
1300 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
1304 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENDROPS
);
1308 static __sum16
tcp_v6_checksum_init(struct sk_buff
*skb
)
1310 if (skb
->ip_summed
== CHECKSUM_COMPLETE
) {
1311 if (!tcp_v6_check(skb
->len
, &ipv6_hdr(skb
)->saddr
,
1312 &ipv6_hdr(skb
)->daddr
, skb
->csum
)) {
1313 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
1318 skb
->csum
= ~csum_unfold(tcp_v6_check(skb
->len
,
1319 &ipv6_hdr(skb
)->saddr
,
1320 &ipv6_hdr(skb
)->daddr
, 0));
1322 if (skb
->len
<= 76) {
1323 return __skb_checksum_complete(skb
);
1328 /* The socket must have it's spinlock held when we get
1331 * We have a potential double-lock case here, so even when
1332 * doing backlog processing we use the BH locking scheme.
1333 * This is because we cannot sleep with the original spinlock
1336 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
)
1338 struct ipv6_pinfo
*np
= inet6_sk(sk
);
1339 struct tcp_sock
*tp
;
1340 struct sk_buff
*opt_skb
= NULL
;
1342 /* Imagine: socket is IPv6. IPv4 packet arrives,
1343 goes to IPv4 receive handler and backlogged.
1344 From backlog it always goes here. Kerboom...
1345 Fortunately, tcp_rcv_established and rcv_established
1346 handle them correctly, but it is not case with
1347 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1350 if (skb
->protocol
== htons(ETH_P_IP
))
1351 return tcp_v4_do_rcv(sk
, skb
);
1353 #ifdef CONFIG_TCP_MD5SIG
1354 if (tcp_v6_inbound_md5_hash (sk
, skb
))
1358 if (sk_filter(sk
, skb
))
1362 * socket locking is here for SMP purposes as backlog rcv
1363 * is currently called with bh processing disabled.
1366 /* Do Stevens' IPV6_PKTOPTIONS.
1368 Yes, guys, it is the only place in our code, where we
1369 may make it not affecting IPv4.
1370 The rest of code is protocol independent,
1371 and I do not like idea to uglify IPv4.
1373 Actually, all the idea behind IPV6_PKTOPTIONS
1374 looks not very well thought. For now we latch
1375 options, received in the last packet, enqueued
1376 by tcp. Feel free to propose better solution.
1380 opt_skb
= skb_clone(skb
, sk_gfp_atomic(sk
, GFP_ATOMIC
));
1382 if (sk
->sk_state
== TCP_ESTABLISHED
) { /* Fast path */
1383 struct dst_entry
*dst
= sk
->sk_rx_dst
;
1385 sock_rps_save_rxhash(sk
, skb
);
1387 if (inet_sk(sk
)->rx_dst_ifindex
!= skb
->skb_iif
||
1388 dst
->ops
->check(dst
, np
->rx_dst_cookie
) == NULL
) {
1390 sk
->sk_rx_dst
= NULL
;
1394 if (tcp_rcv_established(sk
, skb
, tcp_hdr(skb
), skb
->len
))
1397 goto ipv6_pktoptions
;
1401 if (skb
->len
< tcp_hdrlen(skb
) || tcp_checksum_complete(skb
))
1404 if (sk
->sk_state
== TCP_LISTEN
) {
1405 struct sock
*nsk
= tcp_v6_hnd_req(sk
, skb
);
1410 * Queue it on the new socket if the new socket is active,
1411 * otherwise we just shortcircuit this and continue with
1415 sock_rps_save_rxhash(nsk
, skb
);
1416 if (tcp_child_process(sk
, nsk
, skb
))
1419 __kfree_skb(opt_skb
);
1423 sock_rps_save_rxhash(sk
, skb
);
1425 if (tcp_rcv_state_process(sk
, skb
, tcp_hdr(skb
), skb
->len
))
1428 goto ipv6_pktoptions
;
1432 tcp_v6_send_reset(sk
, skb
);
1435 __kfree_skb(opt_skb
);
1439 TCP_INC_STATS_BH(sock_net(sk
), TCP_MIB_INERRS
);
1444 /* Do you ask, what is it?
1446 1. skb was enqueued by tcp.
1447 2. skb is added to tail of read queue, rather than out of order.
1448 3. socket is not in passive state.
1449 4. Finally, it really contains options, which user wants to receive.
1452 if (TCP_SKB_CB(opt_skb
)->end_seq
== tp
->rcv_nxt
&&
1453 !((1 << sk
->sk_state
) & (TCPF_CLOSE
| TCPF_LISTEN
))) {
1454 if (np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
)
1455 np
->mcast_oif
= inet6_iif(opt_skb
);
1456 if (np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
)
1457 np
->mcast_hops
= ipv6_hdr(opt_skb
)->hop_limit
;
1458 if (np
->rxopt
.bits
.rxtclass
)
1459 np
->rcv_tclass
= ipv6_tclass(ipv6_hdr(skb
));
1460 if (ipv6_opt_accepted(sk
, opt_skb
)) {
1461 skb_set_owner_r(opt_skb
, sk
);
1462 opt_skb
= xchg(&np
->pktoptions
, opt_skb
);
1464 __kfree_skb(opt_skb
);
1465 opt_skb
= xchg(&np
->pktoptions
, NULL
);
1473 static int tcp_v6_rcv(struct sk_buff
*skb
)
1475 const struct tcphdr
*th
;
1476 const struct ipv6hdr
*hdr
;
1479 struct net
*net
= dev_net(skb
->dev
);
1481 if (skb
->pkt_type
!= PACKET_HOST
)
1485 * Count it even if it's bad.
1487 TCP_INC_STATS_BH(net
, TCP_MIB_INSEGS
);
1489 if (!pskb_may_pull(skb
, sizeof(struct tcphdr
)))
1494 if (th
->doff
< sizeof(struct tcphdr
)/4)
1496 if (!pskb_may_pull(skb
, th
->doff
*4))
1499 if (!skb_csum_unnecessary(skb
) && tcp_v6_checksum_init(skb
))
1503 hdr
= ipv6_hdr(skb
);
1504 TCP_SKB_CB(skb
)->seq
= ntohl(th
->seq
);
1505 TCP_SKB_CB(skb
)->end_seq
= (TCP_SKB_CB(skb
)->seq
+ th
->syn
+ th
->fin
+
1506 skb
->len
- th
->doff
*4);
1507 TCP_SKB_CB(skb
)->ack_seq
= ntohl(th
->ack_seq
);
1508 TCP_SKB_CB(skb
)->when
= 0;
1509 TCP_SKB_CB(skb
)->ip_dsfield
= ipv6_get_dsfield(hdr
);
1510 TCP_SKB_CB(skb
)->sacked
= 0;
1512 sk
= __inet6_lookup_skb(&tcp_hashinfo
, skb
, th
->source
, th
->dest
);
1517 if (sk
->sk_state
== TCP_TIME_WAIT
)
1520 if (hdr
->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
1521 NET_INC_STATS_BH(net
, LINUX_MIB_TCPMINTTLDROP
);
1522 goto discard_and_relse
;
1525 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
1526 goto discard_and_relse
;
1528 if (sk_filter(sk
, skb
))
1529 goto discard_and_relse
;
1533 bh_lock_sock_nested(sk
);
1535 if (!sock_owned_by_user(sk
)) {
1536 #ifdef CONFIG_NET_DMA
1537 struct tcp_sock
*tp
= tcp_sk(sk
);
1538 if (!tp
->ucopy
.dma_chan
&& tp
->ucopy
.pinned_list
)
1539 tp
->ucopy
.dma_chan
= net_dma_find_channel();
1540 if (tp
->ucopy
.dma_chan
)
1541 ret
= tcp_v6_do_rcv(sk
, skb
);
1545 if (!tcp_prequeue(sk
, skb
))
1546 ret
= tcp_v6_do_rcv(sk
, skb
);
1548 } else if (unlikely(sk_add_backlog(sk
, skb
,
1549 sk
->sk_rcvbuf
+ sk
->sk_sndbuf
))) {
1551 NET_INC_STATS_BH(net
, LINUX_MIB_TCPBACKLOGDROP
);
1552 goto discard_and_relse
;
1557 return ret
? -1 : 0;
1560 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
1563 if (skb
->len
< (th
->doff
<<2) || tcp_checksum_complete(skb
)) {
1565 TCP_INC_STATS_BH(net
, TCP_MIB_INERRS
);
1567 tcp_v6_send_reset(NULL
, skb
);
1584 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
)) {
1585 inet_twsk_put(inet_twsk(sk
));
1589 if (skb
->len
< (th
->doff
<<2) || tcp_checksum_complete(skb
)) {
1590 TCP_INC_STATS_BH(net
, TCP_MIB_INERRS
);
1591 inet_twsk_put(inet_twsk(sk
));
1595 switch (tcp_timewait_state_process(inet_twsk(sk
), skb
, th
)) {
1600 sk2
= inet6_lookup_listener(dev_net(skb
->dev
), &tcp_hashinfo
,
1601 &ipv6_hdr(skb
)->daddr
,
1602 ntohs(th
->dest
), inet6_iif(skb
));
1604 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
1605 inet_twsk_deschedule(tw
, &tcp_death_row
);
1610 /* Fall through to ACK */
1613 tcp_v6_timewait_ack(sk
, skb
);
1617 case TCP_TW_SUCCESS
:;
1622 static void tcp_v6_early_demux(struct sk_buff
*skb
)
1624 const struct ipv6hdr
*hdr
;
1625 const struct tcphdr
*th
;
1628 if (skb
->pkt_type
!= PACKET_HOST
)
1631 if (!pskb_may_pull(skb
, skb_transport_offset(skb
) + sizeof(struct tcphdr
)))
1634 hdr
= ipv6_hdr(skb
);
1637 if (th
->doff
< sizeof(struct tcphdr
) / 4)
1640 sk
= __inet6_lookup_established(dev_net(skb
->dev
), &tcp_hashinfo
,
1641 &hdr
->saddr
, th
->source
,
1642 &hdr
->daddr
, ntohs(th
->dest
),
1646 skb
->destructor
= sock_edemux
;
1647 if (sk
->sk_state
!= TCP_TIME_WAIT
) {
1648 struct dst_entry
*dst
= sk
->sk_rx_dst
;
1651 dst
= dst_check(dst
, inet6_sk(sk
)->rx_dst_cookie
);
1653 inet_sk(sk
)->rx_dst_ifindex
== skb
->skb_iif
)
1654 skb_dst_set_noref(skb
, dst
);
1659 static struct timewait_sock_ops tcp6_timewait_sock_ops
= {
1660 .twsk_obj_size
= sizeof(struct tcp6_timewait_sock
),
1661 .twsk_unique
= tcp_twsk_unique
,
1662 .twsk_destructor
= tcp_twsk_destructor
,
1665 static const struct inet_connection_sock_af_ops ipv6_specific
= {
1666 .queue_xmit
= inet6_csk_xmit
,
1667 .send_check
= tcp_v6_send_check
,
1668 .rebuild_header
= inet6_sk_rebuild_header
,
1669 .sk_rx_dst_set
= inet6_sk_rx_dst_set
,
1670 .conn_request
= tcp_v6_conn_request
,
1671 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1672 .net_header_len
= sizeof(struct ipv6hdr
),
1673 .net_frag_header_len
= sizeof(struct frag_hdr
),
1674 .setsockopt
= ipv6_setsockopt
,
1675 .getsockopt
= ipv6_getsockopt
,
1676 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1677 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1678 .bind_conflict
= inet6_csk_bind_conflict
,
1679 #ifdef CONFIG_COMPAT
1680 .compat_setsockopt
= compat_ipv6_setsockopt
,
1681 .compat_getsockopt
= compat_ipv6_getsockopt
,
1685 #ifdef CONFIG_TCP_MD5SIG
1686 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
= {
1687 .md5_lookup
= tcp_v6_md5_lookup
,
1688 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
1689 .md5_parse
= tcp_v6_parse_md5_keys
,
1694 * TCP over IPv4 via INET6 API
1697 static const struct inet_connection_sock_af_ops ipv6_mapped
= {
1698 .queue_xmit
= ip_queue_xmit
,
1699 .send_check
= tcp_v4_send_check
,
1700 .rebuild_header
= inet_sk_rebuild_header
,
1701 .sk_rx_dst_set
= inet_sk_rx_dst_set
,
1702 .conn_request
= tcp_v6_conn_request
,
1703 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1704 .net_header_len
= sizeof(struct iphdr
),
1705 .setsockopt
= ipv6_setsockopt
,
1706 .getsockopt
= ipv6_getsockopt
,
1707 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1708 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1709 .bind_conflict
= inet6_csk_bind_conflict
,
1710 #ifdef CONFIG_COMPAT
1711 .compat_setsockopt
= compat_ipv6_setsockopt
,
1712 .compat_getsockopt
= compat_ipv6_getsockopt
,
1716 #ifdef CONFIG_TCP_MD5SIG
1717 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
= {
1718 .md5_lookup
= tcp_v4_md5_lookup
,
1719 .calc_md5_hash
= tcp_v4_md5_hash_skb
,
1720 .md5_parse
= tcp_v6_parse_md5_keys
,
1724 /* NOTE: A lot of things set to zero explicitly by call to
1725 * sk_alloc() so need not be done here.
1727 static int tcp_v6_init_sock(struct sock
*sk
)
1729 struct inet_connection_sock
*icsk
= inet_csk(sk
);
1733 icsk
->icsk_af_ops
= &ipv6_specific
;
1735 #ifdef CONFIG_TCP_MD5SIG
1736 tcp_sk(sk
)->af_specific
= &tcp_sock_ipv6_specific
;
1742 static void tcp_v6_destroy_sock(struct sock
*sk
)
1744 tcp_v4_destroy_sock(sk
);
1745 inet6_destroy_sock(sk
);
1748 #ifdef CONFIG_PROC_FS
1749 /* Proc filesystem TCPv6 sock list dumping. */
1750 static void get_openreq6(struct seq_file
*seq
,
1751 const struct sock
*sk
, struct request_sock
*req
, int i
, kuid_t uid
)
1753 int ttd
= req
->expires
- jiffies
;
1754 const struct in6_addr
*src
= &inet6_rsk(req
)->loc_addr
;
1755 const struct in6_addr
*dest
= &inet6_rsk(req
)->rmt_addr
;
1761 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1762 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
1764 src
->s6_addr32
[0], src
->s6_addr32
[1],
1765 src
->s6_addr32
[2], src
->s6_addr32
[3],
1766 ntohs(inet_rsk(req
)->loc_port
),
1767 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1768 dest
->s6_addr32
[2], dest
->s6_addr32
[3],
1769 ntohs(inet_rsk(req
)->rmt_port
),
1771 0,0, /* could print option size, but that is af dependent. */
1772 1, /* timers active (only the expire timer) */
1773 jiffies_to_clock_t(ttd
),
1775 from_kuid_munged(seq_user_ns(seq
), uid
),
1776 0, /* non standard timer */
1777 0, /* open_requests have no inode */
1781 static void get_tcp6_sock(struct seq_file
*seq
, struct sock
*sp
, int i
)
1783 const struct in6_addr
*dest
, *src
;
1786 unsigned long timer_expires
;
1787 const struct inet_sock
*inet
= inet_sk(sp
);
1788 const struct tcp_sock
*tp
= tcp_sk(sp
);
1789 const struct inet_connection_sock
*icsk
= inet_csk(sp
);
1790 const struct ipv6_pinfo
*np
= inet6_sk(sp
);
1793 src
= &np
->rcv_saddr
;
1794 destp
= ntohs(inet
->inet_dport
);
1795 srcp
= ntohs(inet
->inet_sport
);
1797 if (icsk
->icsk_pending
== ICSK_TIME_RETRANS
) {
1799 timer_expires
= icsk
->icsk_timeout
;
1800 } else if (icsk
->icsk_pending
== ICSK_TIME_PROBE0
) {
1802 timer_expires
= icsk
->icsk_timeout
;
1803 } else if (timer_pending(&sp
->sk_timer
)) {
1805 timer_expires
= sp
->sk_timer
.expires
;
1808 timer_expires
= jiffies
;
1812 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1813 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %lu %lu %u %u %d\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
,
1820 tp
->write_seq
-tp
->snd_una
,
1821 (sp
->sk_state
== TCP_LISTEN
) ? sp
->sk_ack_backlog
: (tp
->rcv_nxt
- tp
->copied_seq
),
1823 jiffies_delta_to_clock_t(timer_expires
- jiffies
),
1824 icsk
->icsk_retransmits
,
1825 from_kuid_munged(seq_user_ns(seq
), sock_i_uid(sp
)),
1826 icsk
->icsk_probes_out
,
1828 atomic_read(&sp
->sk_refcnt
), sp
,
1829 jiffies_to_clock_t(icsk
->icsk_rto
),
1830 jiffies_to_clock_t(icsk
->icsk_ack
.ato
),
1831 (icsk
->icsk_ack
.quick
<< 1 ) | icsk
->icsk_ack
.pingpong
,
1833 tcp_in_initial_slowstart(tp
) ? -1 : tp
->snd_ssthresh
1837 static void get_timewait6_sock(struct seq_file
*seq
,
1838 struct inet_timewait_sock
*tw
, int i
)
1840 const struct in6_addr
*dest
, *src
;
1842 const struct inet6_timewait_sock
*tw6
= inet6_twsk((struct sock
*)tw
);
1843 long delta
= tw
->tw_ttd
- jiffies
;
1845 dest
= &tw6
->tw_v6_daddr
;
1846 src
= &tw6
->tw_v6_rcv_saddr
;
1847 destp
= ntohs(tw
->tw_dport
);
1848 srcp
= ntohs(tw
->tw_sport
);
1851 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1852 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
1854 src
->s6_addr32
[0], src
->s6_addr32
[1],
1855 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1856 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1857 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1858 tw
->tw_substate
, 0, 0,
1859 3, jiffies_delta_to_clock_t(delta
), 0, 0, 0, 0,
1860 atomic_read(&tw
->tw_refcnt
), tw
);
1863 static int tcp6_seq_show(struct seq_file
*seq
, void *v
)
1865 struct tcp_iter_state
*st
;
1867 if (v
== SEQ_START_TOKEN
) {
1872 "st tx_queue rx_queue tr tm->when retrnsmt"
1873 " uid timeout inode\n");
1878 switch (st
->state
) {
1879 case TCP_SEQ_STATE_LISTENING
:
1880 case TCP_SEQ_STATE_ESTABLISHED
:
1881 get_tcp6_sock(seq
, v
, st
->num
);
1883 case TCP_SEQ_STATE_OPENREQ
:
1884 get_openreq6(seq
, st
->syn_wait_sk
, v
, st
->num
, st
->uid
);
1886 case TCP_SEQ_STATE_TIME_WAIT
:
1887 get_timewait6_sock(seq
, v
, st
->num
);
1894 static const struct file_operations tcp6_afinfo_seq_fops
= {
1895 .owner
= THIS_MODULE
,
1896 .open
= tcp_seq_open
,
1898 .llseek
= seq_lseek
,
1899 .release
= seq_release_net
1902 static struct tcp_seq_afinfo tcp6_seq_afinfo
= {
1905 .seq_fops
= &tcp6_afinfo_seq_fops
,
1907 .show
= tcp6_seq_show
,
1911 int __net_init
tcp6_proc_init(struct net
*net
)
1913 return tcp_proc_register(net
, &tcp6_seq_afinfo
);
1916 void tcp6_proc_exit(struct net
*net
)
1918 tcp_proc_unregister(net
, &tcp6_seq_afinfo
);
1922 struct proto tcpv6_prot
= {
1924 .owner
= THIS_MODULE
,
1926 .connect
= tcp_v6_connect
,
1927 .disconnect
= tcp_disconnect
,
1928 .accept
= inet_csk_accept
,
1930 .init
= tcp_v6_init_sock
,
1931 .destroy
= tcp_v6_destroy_sock
,
1932 .shutdown
= tcp_shutdown
,
1933 .setsockopt
= tcp_setsockopt
,
1934 .getsockopt
= tcp_getsockopt
,
1935 .recvmsg
= tcp_recvmsg
,
1936 .sendmsg
= tcp_sendmsg
,
1937 .sendpage
= tcp_sendpage
,
1938 .backlog_rcv
= tcp_v6_do_rcv
,
1939 .release_cb
= tcp_release_cb
,
1940 .mtu_reduced
= tcp_v6_mtu_reduced
,
1941 .hash
= tcp_v6_hash
,
1942 .unhash
= inet_unhash
,
1943 .get_port
= inet_csk_get_port
,
1944 .enter_memory_pressure
= tcp_enter_memory_pressure
,
1945 .sockets_allocated
= &tcp_sockets_allocated
,
1946 .memory_allocated
= &tcp_memory_allocated
,
1947 .memory_pressure
= &tcp_memory_pressure
,
1948 .orphan_count
= &tcp_orphan_count
,
1949 .sysctl_wmem
= sysctl_tcp_wmem
,
1950 .sysctl_rmem
= sysctl_tcp_rmem
,
1951 .max_header
= MAX_TCP_HEADER
,
1952 .obj_size
= sizeof(struct tcp6_sock
),
1953 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1954 .twsk_prot
= &tcp6_timewait_sock_ops
,
1955 .rsk_prot
= &tcp6_request_sock_ops
,
1956 .h
.hashinfo
= &tcp_hashinfo
,
1957 .no_autobind
= true,
1958 #ifdef CONFIG_COMPAT
1959 .compat_setsockopt
= compat_tcp_setsockopt
,
1960 .compat_getsockopt
= compat_tcp_getsockopt
,
1962 #ifdef CONFIG_MEMCG_KMEM
1963 .proto_cgroup
= tcp_proto_cgroup
,
1967 static const struct inet6_protocol tcpv6_protocol
= {
1968 .early_demux
= tcp_v6_early_demux
,
1969 .handler
= tcp_v6_rcv
,
1970 .err_handler
= tcp_v6_err
,
1971 .flags
= INET6_PROTO_NOPOLICY
|INET6_PROTO_FINAL
,
1974 static struct inet_protosw tcpv6_protosw
= {
1975 .type
= SOCK_STREAM
,
1976 .protocol
= IPPROTO_TCP
,
1977 .prot
= &tcpv6_prot
,
1978 .ops
= &inet6_stream_ops
,
1980 .flags
= INET_PROTOSW_PERMANENT
|
1984 static int __net_init
tcpv6_net_init(struct net
*net
)
1986 return inet_ctl_sock_create(&net
->ipv6
.tcp_sk
, PF_INET6
,
1987 SOCK_RAW
, IPPROTO_TCP
, net
);
1990 static void __net_exit
tcpv6_net_exit(struct net
*net
)
1992 inet_ctl_sock_destroy(net
->ipv6
.tcp_sk
);
1995 static void __net_exit
tcpv6_net_exit_batch(struct list_head
*net_exit_list
)
1997 inet_twsk_purge(&tcp_hashinfo
, &tcp_death_row
, AF_INET6
);
2000 static struct pernet_operations tcpv6_net_ops
= {
2001 .init
= tcpv6_net_init
,
2002 .exit
= tcpv6_net_exit
,
2003 .exit_batch
= tcpv6_net_exit_batch
,
2006 int __init
tcpv6_init(void)
2010 ret
= inet6_add_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
2014 /* register inet6 protocol */
2015 ret
= inet6_register_protosw(&tcpv6_protosw
);
2017 goto out_tcpv6_protocol
;
2019 ret
= register_pernet_subsys(&tcpv6_net_ops
);
2021 goto out_tcpv6_protosw
;
2026 inet6_unregister_protosw(&tcpv6_protosw
);
2028 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
2032 void tcpv6_exit(void)
2034 unregister_pernet_subsys(&tcpv6_net_ops
);
2035 inet6_unregister_protosw(&tcpv6_protosw
);
2036 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);