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tcp: add const qualifiers where possible
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv6 / tcp_ipv6.c
blobda2ada881cfa324b1318bc6e039dd1b414bcf08d
1 /*
2 * TCP over IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * Based on:
9 * linux/net/ipv4/tcp.c
10 * linux/net/ipv4/tcp_input.c
11 * linux/net/ipv4/tcp_output.c
12 *
13 * Fixes:
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.
19 *
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.
24 */
25
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>
34 #include <linux/in.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
43 #include <linux/ipv6.h>
44 #include <linux/icmpv6.h>
45 #include <linux/random.h>
46
47 #include <net/tcp.h>
48 #include <net/ndisc.h>
49 #include <net/inet6_hashtables.h>
50 #include <net/inet6_connection_sock.h>
51 #include <net/ipv6.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>
58 #include <net/xfrm.h>
59 #include <net/snmp.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
66 #include <asm/uaccess.h>
67
68 #include <linux/proc_fs.h>
69 #include <linux/seq_file.h>
70
71 #include <linux/crypto.h>
72 #include <linux/scatterlist.h>
73
74 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb);
75 static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
76 struct request_sock *req);
77
78 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
79 static void __tcp_v6_send_check(struct sk_buff *skb,
80 const struct in6_addr *saddr,
81 const struct in6_addr *daddr);
82
83 static const struct inet_connection_sock_af_ops ipv6_mapped;
84 static const struct inet_connection_sock_af_ops ipv6_specific;
85 #ifdef CONFIG_TCP_MD5SIG
86 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific;
87 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific;
88 #else
89 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
90 const struct in6_addr *addr)
91 {
92 return NULL;
93 }
94 #endif
95
96 static void tcp_v6_hash(struct sock *sk)
97 {
98 if (sk->sk_state != TCP_CLOSE) {
99 if (inet_csk(sk)->icsk_af_ops == &ipv6_mapped) {
100 tcp_prot.hash(sk);
101 return;
102 }
103 local_bh_disable();
104 __inet6_hash(sk, NULL);
105 local_bh_enable();
106 }
107 }
108
109 static __inline__ __sum16 tcp_v6_check(int len,
110 const struct in6_addr *saddr,
111 const struct in6_addr *daddr,
112 __wsum base)
113 {
114 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
115 }
116
117 static __u32 tcp_v6_init_sequence(const struct sk_buff *skb)
118 {
119 return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
120 ipv6_hdr(skb)->saddr.s6_addr32,
121 tcp_hdr(skb)->dest,
122 tcp_hdr(skb)->source);
123 }
124
125 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
126 int addr_len)
127 {
128 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
129 struct inet_sock *inet = inet_sk(sk);
130 struct inet_connection_sock *icsk = inet_csk(sk);
131 struct ipv6_pinfo *np = inet6_sk(sk);
132 struct tcp_sock *tp = tcp_sk(sk);
133 struct in6_addr *saddr = NULL, *final_p, final;
134 struct rt6_info *rt;
135 struct flowi6 fl6;
136 struct dst_entry *dst;
137 int addr_type;
138 int err;
139
140 if (addr_len < SIN6_LEN_RFC2133)
141 return -EINVAL;
142
143 if (usin->sin6_family != AF_INET6)
144 return -EAFNOSUPPORT;
145
146 memset(&fl6, 0, sizeof(fl6));
147
148 if (np->sndflow) {
149 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
150 IP6_ECN_flow_init(fl6.flowlabel);
151 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
152 struct ip6_flowlabel *flowlabel;
153 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
154 if (flowlabel == NULL)
155 return -EINVAL;
156 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
157 fl6_sock_release(flowlabel);
158 }
159 }
160
161 /*
162 * connect() to INADDR_ANY means loopback (BSD'ism).
163 */
164
165 if(ipv6_addr_any(&usin->sin6_addr))
166 usin->sin6_addr.s6_addr[15] = 0x1;
167
168 addr_type = ipv6_addr_type(&usin->sin6_addr);
169
170 if(addr_type & IPV6_ADDR_MULTICAST)
171 return -ENETUNREACH;
172
173 if (addr_type&IPV6_ADDR_LINKLOCAL) {
174 if (addr_len >= sizeof(struct sockaddr_in6) &&
175 usin->sin6_scope_id) {
176 /* If interface is set while binding, indices
177 * must coincide.
178 */
179 if (sk->sk_bound_dev_if &&
180 sk->sk_bound_dev_if != usin->sin6_scope_id)
181 return -EINVAL;
182
183 sk->sk_bound_dev_if = usin->sin6_scope_id;
184 }
185
186 /* Connect to link-local address requires an interface */
187 if (!sk->sk_bound_dev_if)
188 return -EINVAL;
189 }
190
191 if (tp->rx_opt.ts_recent_stamp &&
192 !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) {
193 tp->rx_opt.ts_recent = 0;
194 tp->rx_opt.ts_recent_stamp = 0;
195 tp->write_seq = 0;
196 }
197
198 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
199 np->flow_label = fl6.flowlabel;
200
201 /*
202 * TCP over IPv4
203 */
204
205 if (addr_type == IPV6_ADDR_MAPPED) {
206 u32 exthdrlen = icsk->icsk_ext_hdr_len;
207 struct sockaddr_in sin;
208
209 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
210
211 if (__ipv6_only_sock(sk))
212 return -ENETUNREACH;
213
214 sin.sin_family = AF_INET;
215 sin.sin_port = usin->sin6_port;
216 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
217
218 icsk->icsk_af_ops = &ipv6_mapped;
219 sk->sk_backlog_rcv = tcp_v4_do_rcv;
220 #ifdef CONFIG_TCP_MD5SIG
221 tp->af_specific = &tcp_sock_ipv6_mapped_specific;
222 #endif
223
224 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
225
226 if (err) {
227 icsk->icsk_ext_hdr_len = exthdrlen;
228 icsk->icsk_af_ops = &ipv6_specific;
229 sk->sk_backlog_rcv = tcp_v6_do_rcv;
230 #ifdef CONFIG_TCP_MD5SIG
231 tp->af_specific = &tcp_sock_ipv6_specific;
232 #endif
233 goto failure;
234 } else {
235 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
236 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
237 &np->rcv_saddr);
238 }
239
240 return err;
241 }
242
243 if (!ipv6_addr_any(&np->rcv_saddr))
244 saddr = &np->rcv_saddr;
245
246 fl6.flowi6_proto = IPPROTO_TCP;
247 ipv6_addr_copy(&fl6.daddr, &np->daddr);
248 ipv6_addr_copy(&fl6.saddr,
249 (saddr ? saddr : &np->saddr));
250 fl6.flowi6_oif = sk->sk_bound_dev_if;
251 fl6.flowi6_mark = sk->sk_mark;
252 fl6.fl6_dport = usin->sin6_port;
253 fl6.fl6_sport = inet->inet_sport;
254
255 final_p = fl6_update_dst(&fl6, np->opt, &final);
256
257 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
258
259 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
260 if (IS_ERR(dst)) {
261 err = PTR_ERR(dst);
262 goto failure;
263 }
264
265 if (saddr == NULL) {
266 saddr = &fl6.saddr;
267 ipv6_addr_copy(&np->rcv_saddr, saddr);
268 }
269
270 /* set the source address */
271 ipv6_addr_copy(&np->saddr, saddr);
272 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
273
274 sk->sk_gso_type = SKB_GSO_TCPV6;
275 __ip6_dst_store(sk, dst, NULL, NULL);
276
277 rt = (struct rt6_info *) dst;
278 if (tcp_death_row.sysctl_tw_recycle &&
279 !tp->rx_opt.ts_recent_stamp &&
280 ipv6_addr_equal(&rt->rt6i_dst.addr, &np->daddr)) {
281 struct inet_peer *peer = rt6_get_peer(rt);
282 /*
283 * VJ's idea. We save last timestamp seen from
284 * the destination in peer table, when entering state
285 * TIME-WAIT * and initialize rx_opt.ts_recent from it,
286 * when trying new connection.
287 */
288 if (peer) {
289 inet_peer_refcheck(peer);
290 if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) {
291 tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp;
292 tp->rx_opt.ts_recent = peer->tcp_ts;
293 }
294 }
295 }
296
297 icsk->icsk_ext_hdr_len = 0;
298 if (np->opt)
299 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
300 np->opt->opt_nflen);
301
302 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
303
304 inet->inet_dport = usin->sin6_port;
305
306 tcp_set_state(sk, TCP_SYN_SENT);
307 err = inet6_hash_connect(&tcp_death_row, sk);
308 if (err)
309 goto late_failure;
310
311 if (!tp->write_seq)
312 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
313 np->daddr.s6_addr32,
314 inet->inet_sport,
315 inet->inet_dport);
316
317 err = tcp_connect(sk);
318 if (err)
319 goto late_failure;
320
321 return 0;
322
323 late_failure:
324 tcp_set_state(sk, TCP_CLOSE);
325 __sk_dst_reset(sk);
326 failure:
327 inet->inet_dport = 0;
328 sk->sk_route_caps = 0;
329 return err;
330 }
331
332 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
333 u8 type, u8 code, int offset, __be32 info)
334 {
335 const struct ipv6hdr *hdr = (const struct ipv6hdr*)skb->data;
336 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
337 struct ipv6_pinfo *np;
338 struct sock *sk;
339 int err;
340 struct tcp_sock *tp;
341 __u32 seq;
342 struct net *net = dev_net(skb->dev);
343
344 sk = inet6_lookup(net, &tcp_hashinfo, &hdr->daddr,
345 th->dest, &hdr->saddr, th->source, skb->dev->ifindex);
346
347 if (sk == NULL) {
348 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
349 ICMP6_MIB_INERRORS);
350 return;
351 }
352
353 if (sk->sk_state == TCP_TIME_WAIT) {
354 inet_twsk_put(inet_twsk(sk));
355 return;
356 }
357
358 bh_lock_sock(sk);
359 if (sock_owned_by_user(sk))
360 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
361
362 if (sk->sk_state == TCP_CLOSE)
363 goto out;
364
365 if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) {
366 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
367 goto out;
368 }
369
370 tp = tcp_sk(sk);
371 seq = ntohl(th->seq);
372 if (sk->sk_state != TCP_LISTEN &&
373 !between(seq, tp->snd_una, tp->snd_nxt)) {
374 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
375 goto out;
376 }
377
378 np = inet6_sk(sk);
379
380 if (type == ICMPV6_PKT_TOOBIG) {
381 struct dst_entry *dst;
382
383 if (sock_owned_by_user(sk))
384 goto out;
385 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
386 goto out;
387
388 /* icmp should have updated the destination cache entry */
389 dst = __sk_dst_check(sk, np->dst_cookie);
390
391 if (dst == NULL) {
392 struct inet_sock *inet = inet_sk(sk);
393 struct flowi6 fl6;
394
395 /* BUGGG_FUTURE: Again, it is not clear how
396 to handle rthdr case. Ignore this complexity
397 for now.
398 */
399 memset(&fl6, 0, sizeof(fl6));
400 fl6.flowi6_proto = IPPROTO_TCP;
401 ipv6_addr_copy(&fl6.daddr, &np->daddr);
402 ipv6_addr_copy(&fl6.saddr, &np->saddr);
403 fl6.flowi6_oif = sk->sk_bound_dev_if;
404 fl6.flowi6_mark = sk->sk_mark;
405 fl6.fl6_dport = inet->inet_dport;
406 fl6.fl6_sport = inet->inet_sport;
407 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
408
409 dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
410 if (IS_ERR(dst)) {
411 sk->sk_err_soft = -PTR_ERR(dst);
412 goto out;
413 }
414
415 } else
416 dst_hold(dst);
417
418 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
419 tcp_sync_mss(sk, dst_mtu(dst));
420 tcp_simple_retransmit(sk);
421 } /* else let the usual retransmit timer handle it */
422 dst_release(dst);
423 goto out;
424 }
425
426 icmpv6_err_convert(type, code, &err);
427
428 /* Might be for an request_sock */
429 switch (sk->sk_state) {
430 struct request_sock *req, **prev;
431 case TCP_LISTEN:
432 if (sock_owned_by_user(sk))
433 goto out;
434
435 req = inet6_csk_search_req(sk, &prev, th->dest, &hdr->daddr,
436 &hdr->saddr, inet6_iif(skb));
437 if (!req)
438 goto out;
439
440 /* ICMPs are not backlogged, hence we cannot get
441 * an established socket here.
442 */
443 WARN_ON(req->sk != NULL);
444
445 if (seq != tcp_rsk(req)->snt_isn) {
446 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
447 goto out;
448 }
449
450 inet_csk_reqsk_queue_drop(sk, req, prev);
451 goto out;
452
453 case TCP_SYN_SENT:
454 case TCP_SYN_RECV: /* Cannot happen.
455 It can, it SYNs are crossed. --ANK */
456 if (!sock_owned_by_user(sk)) {
457 sk->sk_err = err;
458 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */
459
460 tcp_done(sk);
461 } else
462 sk->sk_err_soft = err;
463 goto out;
464 }
465
466 if (!sock_owned_by_user(sk) && np->recverr) {
467 sk->sk_err = err;
468 sk->sk_error_report(sk);
469 } else
470 sk->sk_err_soft = err;
471
472 out:
473 bh_unlock_sock(sk);
474 sock_put(sk);
475 }
476
477
478 static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
479 struct request_values *rvp)
480 {
481 struct inet6_request_sock *treq = inet6_rsk(req);
482 struct ipv6_pinfo *np = inet6_sk(sk);
483 struct sk_buff * skb;
484 struct ipv6_txoptions *opt = NULL;
485 struct in6_addr * final_p, final;
486 struct flowi6 fl6;
487 struct dst_entry *dst;
488 int err;
489
490 memset(&fl6, 0, sizeof(fl6));
491 fl6.flowi6_proto = IPPROTO_TCP;
492 ipv6_addr_copy(&fl6.daddr, &treq->rmt_addr);
493 ipv6_addr_copy(&fl6.saddr, &treq->loc_addr);
494 fl6.flowlabel = 0;
495 fl6.flowi6_oif = treq->iif;
496 fl6.flowi6_mark = sk->sk_mark;
497 fl6.fl6_dport = inet_rsk(req)->rmt_port;
498 fl6.fl6_sport = inet_rsk(req)->loc_port;
499 security_req_classify_flow(req, flowi6_to_flowi(&fl6));
500
501 opt = np->opt;
502 final_p = fl6_update_dst(&fl6, opt, &final);
503
504 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
505 if (IS_ERR(dst)) {
506 err = PTR_ERR(dst);
507 dst = NULL;
508 goto done;
509 }
510 skb = tcp_make_synack(sk, dst, req, rvp);
511 err = -ENOMEM;
512 if (skb) {
513 __tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr);
514
515 ipv6_addr_copy(&fl6.daddr, &treq->rmt_addr);
516 err = ip6_xmit(sk, skb, &fl6, opt);
517 err = net_xmit_eval(err);
518 }
519
520 done:
521 if (opt && opt != np->opt)
522 sock_kfree_s(sk, opt, opt->tot_len);
523 dst_release(dst);
524 return err;
525 }
526
527 static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req,
528 struct request_values *rvp)
529 {
530 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
531 return tcp_v6_send_synack(sk, req, rvp);
532 }
533
534 static void tcp_v6_reqsk_destructor(struct request_sock *req)
535 {
536 kfree_skb(inet6_rsk(req)->pktopts);
537 }
538
539 #ifdef CONFIG_TCP_MD5SIG
540 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
541 const struct in6_addr *addr)
542 {
543 struct tcp_sock *tp = tcp_sk(sk);
544 int i;
545
546 BUG_ON(tp == NULL);
547
548 if (!tp->md5sig_info || !tp->md5sig_info->entries6)
549 return NULL;
550
551 for (i = 0; i < tp->md5sig_info->entries6; i++) {
552 if (ipv6_addr_equal(&tp->md5sig_info->keys6[i].addr, addr))
553 return &tp->md5sig_info->keys6[i].base;
554 }
555 return NULL;
556 }
557
558 static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk,
559 struct sock *addr_sk)
560 {
561 return tcp_v6_md5_do_lookup(sk, &inet6_sk(addr_sk)->daddr);
562 }
563
564 static struct tcp_md5sig_key *tcp_v6_reqsk_md5_lookup(struct sock *sk,
565 struct request_sock *req)
566 {
567 return tcp_v6_md5_do_lookup(sk, &inet6_rsk(req)->rmt_addr);
568 }
569
570 static int tcp_v6_md5_do_add(struct sock *sk, const struct in6_addr *peer,
571 char *newkey, u8 newkeylen)
572 {
573 /* Add key to the list */
574 struct tcp_md5sig_key *key;
575 struct tcp_sock *tp = tcp_sk(sk);
576 struct tcp6_md5sig_key *keys;
577
578 key = tcp_v6_md5_do_lookup(sk, peer);
579 if (key) {
580 /* modify existing entry - just update that one */
581 kfree(key->key);
582 key->key = newkey;
583 key->keylen = newkeylen;
584 } else {
585 /* reallocate new list if current one is full. */
586 if (!tp->md5sig_info) {
587 tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC);
588 if (!tp->md5sig_info) {
589 kfree(newkey);
590 return -ENOMEM;
591 }
592 sk_nocaps_add(sk, NETIF_F_GSO_MASK);
593 }
594 if (tp->md5sig_info->entries6 == 0 &&
595 tcp_alloc_md5sig_pool(sk) == NULL) {
596 kfree(newkey);
597 return -ENOMEM;
598 }
599 if (tp->md5sig_info->alloced6 == tp->md5sig_info->entries6) {
600 keys = kmalloc((sizeof (tp->md5sig_info->keys6[0]) *
601 (tp->md5sig_info->entries6 + 1)), GFP_ATOMIC);
602
603 if (!keys) {
604 kfree(newkey);
605 if (tp->md5sig_info->entries6 == 0)
606 tcp_free_md5sig_pool();
607 return -ENOMEM;
608 }
609
610 if (tp->md5sig_info->entries6)
611 memmove(keys, tp->md5sig_info->keys6,
612 (sizeof (tp->md5sig_info->keys6[0]) *
613 tp->md5sig_info->entries6));
614
615 kfree(tp->md5sig_info->keys6);
616 tp->md5sig_info->keys6 = keys;
617 tp->md5sig_info->alloced6++;
618 }
619
620 ipv6_addr_copy(&tp->md5sig_info->keys6[tp->md5sig_info->entries6].addr,
621 peer);
622 tp->md5sig_info->keys6[tp->md5sig_info->entries6].base.key = newkey;
623 tp->md5sig_info->keys6[tp->md5sig_info->entries6].base.keylen = newkeylen;
624
625 tp->md5sig_info->entries6++;
626 }
627 return 0;
628 }
629
630 static int tcp_v6_md5_add_func(struct sock *sk, struct sock *addr_sk,
631 u8 *newkey, __u8 newkeylen)
632 {
633 return tcp_v6_md5_do_add(sk, &inet6_sk(addr_sk)->daddr,
634 newkey, newkeylen);
635 }
636
637 static int tcp_v6_md5_do_del(struct sock *sk, const struct in6_addr *peer)
638 {
639 struct tcp_sock *tp = tcp_sk(sk);
640 int i;
641
642 for (i = 0; i < tp->md5sig_info->entries6; i++) {
643 if (ipv6_addr_equal(&tp->md5sig_info->keys6[i].addr, peer)) {
644 /* Free the key */
645 kfree(tp->md5sig_info->keys6[i].base.key);
646 tp->md5sig_info->entries6--;
647
648 if (tp->md5sig_info->entries6 == 0) {
649 kfree(tp->md5sig_info->keys6);
650 tp->md5sig_info->keys6 = NULL;
651 tp->md5sig_info->alloced6 = 0;
652 tcp_free_md5sig_pool();
653 } else {
654 /* shrink the database */
655 if (tp->md5sig_info->entries6 != i)
656 memmove(&tp->md5sig_info->keys6[i],
657 &tp->md5sig_info->keys6[i+1],
658 (tp->md5sig_info->entries6 - i)
659 * sizeof (tp->md5sig_info->keys6[0]));
660 }
661 return 0;
662 }
663 }
664 return -ENOENT;
665 }
666
667 static void tcp_v6_clear_md5_list (struct sock *sk)
668 {
669 struct tcp_sock *tp = tcp_sk(sk);
670 int i;
671
672 if (tp->md5sig_info->entries6) {
673 for (i = 0; i < tp->md5sig_info->entries6; i++)
674 kfree(tp->md5sig_info->keys6[i].base.key);
675 tp->md5sig_info->entries6 = 0;
676 tcp_free_md5sig_pool();
677 }
678
679 kfree(tp->md5sig_info->keys6);
680 tp->md5sig_info->keys6 = NULL;
681 tp->md5sig_info->alloced6 = 0;
682
683 if (tp->md5sig_info->entries4) {
684 for (i = 0; i < tp->md5sig_info->entries4; i++)
685 kfree(tp->md5sig_info->keys4[i].base.key);
686 tp->md5sig_info->entries4 = 0;
687 tcp_free_md5sig_pool();
688 }
689
690 kfree(tp->md5sig_info->keys4);
691 tp->md5sig_info->keys4 = NULL;
692 tp->md5sig_info->alloced4 = 0;
693 }
694
695 static int tcp_v6_parse_md5_keys (struct sock *sk, char __user *optval,
696 int optlen)
697 {
698 struct tcp_md5sig cmd;
699 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr;
700 u8 *newkey;
701
702 if (optlen < sizeof(cmd))
703 return -EINVAL;
704
705 if (copy_from_user(&cmd, optval, sizeof(cmd)))
706 return -EFAULT;
707
708 if (sin6->sin6_family != AF_INET6)
709 return -EINVAL;
710
711 if (!cmd.tcpm_keylen) {
712 if (!tcp_sk(sk)->md5sig_info)
713 return -ENOENT;
714 if (ipv6_addr_v4mapped(&sin6->sin6_addr))
715 return tcp_v4_md5_do_del(sk, sin6->sin6_addr.s6_addr32[3]);
716 return tcp_v6_md5_do_del(sk, &sin6->sin6_addr);
717 }
718
719 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
720 return -EINVAL;
721
722 if (!tcp_sk(sk)->md5sig_info) {
723 struct tcp_sock *tp = tcp_sk(sk);
724 struct tcp_md5sig_info *p;
725
726 p = kzalloc(sizeof(struct tcp_md5sig_info), GFP_KERNEL);
727 if (!p)
728 return -ENOMEM;
729
730 tp->md5sig_info = p;
731 sk_nocaps_add(sk, NETIF_F_GSO_MASK);
732 }
733
734 newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
735 if (!newkey)
736 return -ENOMEM;
737 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
738 return tcp_v4_md5_do_add(sk, sin6->sin6_addr.s6_addr32[3],
739 newkey, cmd.tcpm_keylen);
740 }
741 return tcp_v6_md5_do_add(sk, &sin6->sin6_addr, newkey, cmd.tcpm_keylen);
742 }
743
744 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp,
745 const struct in6_addr *daddr,
746 const struct in6_addr *saddr, int nbytes)
747 {
748 struct tcp6_pseudohdr *bp;
749 struct scatterlist sg;
750
751 bp = &hp->md5_blk.ip6;
752 /* 1. TCP pseudo-header (RFC2460) */
753 ipv6_addr_copy(&bp->saddr, saddr);
754 ipv6_addr_copy(&bp->daddr, daddr);
755 bp->protocol = cpu_to_be32(IPPROTO_TCP);
756 bp->len = cpu_to_be32(nbytes);
757
758 sg_init_one(&sg, bp, sizeof(*bp));
759 return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp));
760 }
761
762 static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key,
763 const struct in6_addr *daddr, struct in6_addr *saddr,
764 struct tcphdr *th)
765 {
766 struct tcp_md5sig_pool *hp;
767 struct hash_desc *desc;
768
769 hp = tcp_get_md5sig_pool();
770 if (!hp)
771 goto clear_hash_noput;
772 desc = &hp->md5_desc;
773
774 if (crypto_hash_init(desc))
775 goto clear_hash;
776 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2))
777 goto clear_hash;
778 if (tcp_md5_hash_header(hp, th))
779 goto clear_hash;
780 if (tcp_md5_hash_key(hp, key))
781 goto clear_hash;
782 if (crypto_hash_final(desc, md5_hash))
783 goto clear_hash;
784
785 tcp_put_md5sig_pool();
786 return 0;
787
788 clear_hash:
789 tcp_put_md5sig_pool();
790 clear_hash_noput:
791 memset(md5_hash, 0, 16);
792 return 1;
793 }
794
795 static int tcp_v6_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
796 struct sock *sk, struct request_sock *req,
797 struct sk_buff *skb)
798 {
799 const struct in6_addr *saddr, *daddr;
800 struct tcp_md5sig_pool *hp;
801 struct hash_desc *desc;
802 struct tcphdr *th = tcp_hdr(skb);
803
804 if (sk) {
805 saddr = &inet6_sk(sk)->saddr;
806 daddr = &inet6_sk(sk)->daddr;
807 } else if (req) {
808 saddr = &inet6_rsk(req)->loc_addr;
809 daddr = &inet6_rsk(req)->rmt_addr;
810 } else {
811 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
812 saddr = &ip6h->saddr;
813 daddr = &ip6h->daddr;
814 }
815
816 hp = tcp_get_md5sig_pool();
817 if (!hp)
818 goto clear_hash_noput;
819 desc = &hp->md5_desc;
820
821 if (crypto_hash_init(desc))
822 goto clear_hash;
823
824 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len))
825 goto clear_hash;
826 if (tcp_md5_hash_header(hp, th))
827 goto clear_hash;
828 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
829 goto clear_hash;
830 if (tcp_md5_hash_key(hp, key))
831 goto clear_hash;
832 if (crypto_hash_final(desc, md5_hash))
833 goto clear_hash;
834
835 tcp_put_md5sig_pool();
836 return 0;
837
838 clear_hash:
839 tcp_put_md5sig_pool();
840 clear_hash_noput:
841 memset(md5_hash, 0, 16);
842 return 1;
843 }
844
845 static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
846 {
847 const __u8 *hash_location = NULL;
848 struct tcp_md5sig_key *hash_expected;
849 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
850 struct tcphdr *th = tcp_hdr(skb);
851 int genhash;
852 u8 newhash[16];
853
854 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr);
855 hash_location = tcp_parse_md5sig_option(th);
856
857 /* We've parsed the options - do we have a hash? */
858 if (!hash_expected && !hash_location)
859 return 0;
860
861 if (hash_expected && !hash_location) {
862 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
863 return 1;
864 }
865
866 if (!hash_expected && hash_location) {
867 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
868 return 1;
869 }
870
871 /* check the signature */
872 genhash = tcp_v6_md5_hash_skb(newhash,
873 hash_expected,
874 NULL, NULL, skb);
875
876 if (genhash || memcmp(hash_location, newhash, 16) != 0) {
877 if (net_ratelimit()) {
878 printk(KERN_INFO "MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
879 genhash ? "failed" : "mismatch",
880 &ip6h->saddr, ntohs(th->source),
881 &ip6h->daddr, ntohs(th->dest));
882 }
883 return 1;
884 }
885 return 0;
886 }
887 #endif
888
889 struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
890 .family = AF_INET6,
891 .obj_size = sizeof(struct tcp6_request_sock),
892 .rtx_syn_ack = tcp_v6_rtx_synack,
893 .send_ack = tcp_v6_reqsk_send_ack,
894 .destructor = tcp_v6_reqsk_destructor,
895 .send_reset = tcp_v6_send_reset,
896 .syn_ack_timeout = tcp_syn_ack_timeout,
897 };
898
899 #ifdef CONFIG_TCP_MD5SIG
900 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
901 .md5_lookup = tcp_v6_reqsk_md5_lookup,
902 .calc_md5_hash = tcp_v6_md5_hash_skb,
903 };
904 #endif
905
906 static void __tcp_v6_send_check(struct sk_buff *skb,
907 const struct in6_addr *saddr, const struct in6_addr *daddr)
908 {
909 struct tcphdr *th = tcp_hdr(skb);
910
911 if (skb->ip_summed == CHECKSUM_PARTIAL) {
912 th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0);
913 skb->csum_start = skb_transport_header(skb) - skb->head;
914 skb->csum_offset = offsetof(struct tcphdr, check);
915 } else {
916 th->check = tcp_v6_check(skb->len, saddr, daddr,
917 csum_partial(th, th->doff << 2,
918 skb->csum));
919 }
920 }
921
922 static void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
923 {
924 struct ipv6_pinfo *np = inet6_sk(sk);
925
926 __tcp_v6_send_check(skb, &np->saddr, &np->daddr);
927 }
928
929 static int tcp_v6_gso_send_check(struct sk_buff *skb)
930 {
931 const struct ipv6hdr *ipv6h;
932 struct tcphdr *th;
933
934 if (!pskb_may_pull(skb, sizeof(*th)))
935 return -EINVAL;
936
937 ipv6h = ipv6_hdr(skb);
938 th = tcp_hdr(skb);
939
940 th->check = 0;
941 skb->ip_summed = CHECKSUM_PARTIAL;
942 __tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr);
943 return 0;
944 }
945
946 static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
947 struct sk_buff *skb)
948 {
949 const struct ipv6hdr *iph = skb_gro_network_header(skb);
950
951 switch (skb->ip_summed) {
952 case CHECKSUM_COMPLETE:
953 if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr,
954 skb->csum)) {
955 skb->ip_summed = CHECKSUM_UNNECESSARY;
956 break;
957 }
958
959 /* fall through */
960 case CHECKSUM_NONE:
961 NAPI_GRO_CB(skb)->flush = 1;
962 return NULL;
963 }
964
965 return tcp_gro_receive(head, skb);
966 }
967
968 static int tcp6_gro_complete(struct sk_buff *skb)
969 {
970 const struct ipv6hdr *iph = ipv6_hdr(skb);
971 struct tcphdr *th = tcp_hdr(skb);
972
973 th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb),
974 &iph->saddr, &iph->daddr, 0);
975 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
976
977 return tcp_gro_complete(skb);
978 }
979
980 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
981 u32 ts, struct tcp_md5sig_key *key, int rst)
982 {
983 const struct tcphdr *th = tcp_hdr(skb);
984 struct tcphdr *t1;
985 struct sk_buff *buff;
986 struct flowi6 fl6;
987 struct net *net = dev_net(skb_dst(skb)->dev);
988 struct sock *ctl_sk = net->ipv6.tcp_sk;
989 unsigned int tot_len = sizeof(struct tcphdr);
990 struct dst_entry *dst;
991 __be32 *topt;
992
993 if (ts)
994 tot_len += TCPOLEN_TSTAMP_ALIGNED;
995 #ifdef CONFIG_TCP_MD5SIG
996 if (key)
997 tot_len += TCPOLEN_MD5SIG_ALIGNED;
998 #endif
999
1000 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
1001 GFP_ATOMIC);
1002 if (buff == NULL)
1003 return;
1004
1005 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
1006
1007 t1 = (struct tcphdr *) skb_push(buff, tot_len);
1008 skb_reset_transport_header(buff);
1009
1010 /* Swap the send and the receive. */
1011 memset(t1, 0, sizeof(*t1));
1012 t1->dest = th->source;
1013 t1->source = th->dest;
1014 t1->doff = tot_len / 4;
1015 t1->seq = htonl(seq);
1016 t1->ack_seq = htonl(ack);
1017 t1->ack = !rst || !th->ack;
1018 t1->rst = rst;
1019 t1->window = htons(win);
1020
1021 topt = (__be32 *)(t1 + 1);
1022
1023 if (ts) {
1024 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
1025 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
1026 *topt++ = htonl(tcp_time_stamp);
1027 *topt++ = htonl(ts);
1028 }
1029
1030 #ifdef CONFIG_TCP_MD5SIG
1031 if (key) {
1032 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
1033 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG);
1034 tcp_v6_md5_hash_hdr((__u8 *)topt, key,
1035 &ipv6_hdr(skb)->saddr,
1036 &ipv6_hdr(skb)->daddr, t1);
1037 }
1038 #endif
1039
1040 memset(&fl6, 0, sizeof(fl6));
1041 ipv6_addr_copy(&fl6.daddr, &ipv6_hdr(skb)->saddr);
1042 ipv6_addr_copy(&fl6.saddr, &ipv6_hdr(skb)->daddr);
1043
1044 buff->ip_summed = CHECKSUM_PARTIAL;
1045 buff->csum = 0;
1046
1047 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr);
1048
1049 fl6.flowi6_proto = IPPROTO_TCP;
1050 fl6.flowi6_oif = inet6_iif(skb);
1051 fl6.fl6_dport = t1->dest;
1052 fl6.fl6_sport = t1->source;
1053 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
1054
1055 /* Pass a socket to ip6_dst_lookup either it is for RST
1056 * Underlying function will use this to retrieve the network
1057 * namespace
1058 */
1059 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false);
1060 if (!IS_ERR(dst)) {
1061 skb_dst_set(buff, dst);
1062 ip6_xmit(ctl_sk, buff, &fl6, NULL);
1063 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS);
1064 if (rst)
1065 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS);
1066 return;
1067 }
1068
1069 kfree_skb(buff);
1070 }
1071
1072 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb)
1073 {
1074 const struct tcphdr *th = tcp_hdr(skb);
1075 u32 seq = 0, ack_seq = 0;
1076 struct tcp_md5sig_key *key = NULL;
1077
1078 if (th->rst)
1079 return;
1080
1081 if (!ipv6_unicast_destination(skb))
1082 return;
1083
1084 #ifdef CONFIG_TCP_MD5SIG
1085 if (sk)
1086 key = tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr);
1087 #endif
1088
1089 if (th->ack)
1090 seq = ntohl(th->ack_seq);
1091 else
1092 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len -
1093 (th->doff << 2);
1094
1095 tcp_v6_send_response(skb, seq, ack_seq, 0, 0, key, 1);
1096 }
1097
1098 static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts,
1099 struct tcp_md5sig_key *key)
1100 {
1101 tcp_v6_send_response(skb, seq, ack, win, ts, key, 0);
1102 }
1103
1104 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
1105 {
1106 struct inet_timewait_sock *tw = inet_twsk(sk);
1107 struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
1108
1109 tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
1110 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
1111 tcptw->tw_ts_recent, tcp_twsk_md5_key(tcptw));
1112
1113 inet_twsk_put(tw);
1114 }
1115
1116 static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
1117 struct request_sock *req)
1118 {
1119 tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent,
1120 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr));
1121 }
1122
1123
1124 static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
1125 {
1126 struct request_sock *req, **prev;
1127 const struct tcphdr *th = tcp_hdr(skb);
1128 struct sock *nsk;
1129
1130 /* Find possible connection requests. */
1131 req = inet6_csk_search_req(sk, &prev, th->source,
1132 &ipv6_hdr(skb)->saddr,
1133 &ipv6_hdr(skb)->daddr, inet6_iif(skb));
1134 if (req)
1135 return tcp_check_req(sk, skb, req, prev);
1136
1137 nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo,
1138 &ipv6_hdr(skb)->saddr, th->source,
1139 &ipv6_hdr(skb)->daddr, ntohs(th->dest), inet6_iif(skb));
1140
1141 if (nsk) {
1142 if (nsk->sk_state != TCP_TIME_WAIT) {
1143 bh_lock_sock(nsk);
1144 return nsk;
1145 }
1146 inet_twsk_put(inet_twsk(nsk));
1147 return NULL;
1148 }
1149
1150 #ifdef CONFIG_SYN_COOKIES
1151 if (!th->syn)
1152 sk = cookie_v6_check(sk, skb);
1153 #endif
1154 return sk;
1155 }
1156
1157 /* FIXME: this is substantially similar to the ipv4 code.
1158 * Can some kind of merge be done? -- erics
1159 */
1160 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
1161 {
1162 struct tcp_extend_values tmp_ext;
1163 struct tcp_options_received tmp_opt;
1164 const u8 *hash_location;
1165 struct request_sock *req;
1166 struct inet6_request_sock *treq;
1167 struct ipv6_pinfo *np = inet6_sk(sk);
1168 struct tcp_sock *tp = tcp_sk(sk);
1169 __u32 isn = TCP_SKB_CB(skb)->when;
1170 struct dst_entry *dst = NULL;
1171 int want_cookie = 0;
1172
1173 if (skb->protocol == htons(ETH_P_IP))
1174 return tcp_v4_conn_request(sk, skb);
1175
1176 if (!ipv6_unicast_destination(skb))
1177 goto drop;
1178
1179 if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
1180 want_cookie = tcp_syn_flood_action(sk, skb, "TCPv6");
1181 if (!want_cookie)
1182 goto drop;
1183 }
1184
1185 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
1186 goto drop;
1187
1188 req = inet6_reqsk_alloc(&tcp6_request_sock_ops);
1189 if (req == NULL)
1190 goto drop;
1191
1192 #ifdef CONFIG_TCP_MD5SIG
1193 tcp_rsk(req)->af_specific = &tcp_request_sock_ipv6_ops;
1194 #endif
1195
1196 tcp_clear_options(&tmp_opt);
1197 tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
1198 tmp_opt.user_mss = tp->rx_opt.user_mss;
1199 tcp_parse_options(skb, &tmp_opt, &hash_location, 0);
1200
1201 if (tmp_opt.cookie_plus > 0 &&
1202 tmp_opt.saw_tstamp &&
1203 !tp->rx_opt.cookie_out_never &&
1204 (sysctl_tcp_cookie_size > 0 ||
1205 (tp->cookie_values != NULL &&
1206 tp->cookie_values->cookie_desired > 0))) {
1207 u8 *c;
1208 u32 *d;
1209 u32 *mess = &tmp_ext.cookie_bakery[COOKIE_DIGEST_WORDS];
1210 int l = tmp_opt.cookie_plus - TCPOLEN_COOKIE_BASE;
1211
1212 if (tcp_cookie_generator(&tmp_ext.cookie_bakery[0]) != 0)
1213 goto drop_and_free;
1214
1215 /* Secret recipe starts with IP addresses */
1216 d = (__force u32 *)&ipv6_hdr(skb)->daddr.s6_addr32[0];
1217 *mess++ ^= *d++;
1218 *mess++ ^= *d++;
1219 *mess++ ^= *d++;
1220 *mess++ ^= *d++;
1221 d = (__force u32 *)&ipv6_hdr(skb)->saddr.s6_addr32[0];
1222 *mess++ ^= *d++;
1223 *mess++ ^= *d++;
1224 *mess++ ^= *d++;
1225 *mess++ ^= *d++;
1226
1227 /* plus variable length Initiator Cookie */
1228 c = (u8 *)mess;
1229 while (l-- > 0)
1230 *c++ ^= *hash_location++;
1231
1232 want_cookie = 0; /* not our kind of cookie */
1233 tmp_ext.cookie_out_never = 0; /* false */
1234 tmp_ext.cookie_plus = tmp_opt.cookie_plus;
1235 } else if (!tp->rx_opt.cookie_in_always) {
1236 /* redundant indications, but ensure initialization. */
1237 tmp_ext.cookie_out_never = 1; /* true */
1238 tmp_ext.cookie_plus = 0;
1239 } else {
1240 goto drop_and_free;
1241 }
1242 tmp_ext.cookie_in_always = tp->rx_opt.cookie_in_always;
1243
1244 if (want_cookie && !tmp_opt.saw_tstamp)
1245 tcp_clear_options(&tmp_opt);
1246
1247 tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
1248 tcp_openreq_init(req, &tmp_opt, skb);
1249
1250 treq = inet6_rsk(req);
1251 ipv6_addr_copy(&treq->rmt_addr, &ipv6_hdr(skb)->saddr);
1252 ipv6_addr_copy(&treq->loc_addr, &ipv6_hdr(skb)->daddr);
1253 if (!want_cookie || tmp_opt.tstamp_ok)
1254 TCP_ECN_create_request(req, tcp_hdr(skb));
1255
1256 if (!isn) {
1257 struct inet_peer *peer = NULL;
1258
1259 if (ipv6_opt_accepted(sk, skb) ||
1260 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
1261 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
1262 atomic_inc(&skb->users);
1263 treq->pktopts = skb;
1264 }
1265 treq->iif = sk->sk_bound_dev_if;
1266
1267 /* So that link locals have meaning */
1268 if (!sk->sk_bound_dev_if &&
1269 ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
1270 treq->iif = inet6_iif(skb);
1271
1272 if (want_cookie) {
1273 isn = cookie_v6_init_sequence(sk, skb, &req->mss);
1274 req->cookie_ts = tmp_opt.tstamp_ok;
1275 goto have_isn;
1276 }
1277
1278 /* VJ's idea. We save last timestamp seen
1279 * from the destination in peer table, when entering
1280 * state TIME-WAIT, and check against it before
1281 * accepting new connection request.
1282 *
1283 * If "isn" is not zero, this request hit alive
1284 * timewait bucket, so that all the necessary checks
1285 * are made in the function processing timewait state.
1286 */
1287 if (tmp_opt.saw_tstamp &&
1288 tcp_death_row.sysctl_tw_recycle &&
1289 (dst = inet6_csk_route_req(sk, req)) != NULL &&
1290 (peer = rt6_get_peer((struct rt6_info *)dst)) != NULL &&
1291 ipv6_addr_equal((struct in6_addr *)peer->daddr.addr.a6,
1292 &treq->rmt_addr)) {
1293 inet_peer_refcheck(peer);
1294 if ((u32)get_seconds() - peer->tcp_ts_stamp < TCP_PAWS_MSL &&
1295 (s32)(peer->tcp_ts - req->ts_recent) >
1296 TCP_PAWS_WINDOW) {
1297 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
1298 goto drop_and_release;
1299 }
1300 }
1301 /* Kill the following clause, if you dislike this way. */
1302 else if (!sysctl_tcp_syncookies &&
1303 (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) <
1304 (sysctl_max_syn_backlog >> 2)) &&
1305 (!peer || !peer->tcp_ts_stamp) &&
1306 (!dst || !dst_metric(dst, RTAX_RTT))) {
1307 /* Without syncookies last quarter of
1308 * backlog is filled with destinations,
1309 * proven to be alive.
1310 * It means that we continue to communicate
1311 * to destinations, already remembered
1312 * to the moment of synflood.
1313 */
1314 LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open request from %pI6/%u\n",
1315 &treq->rmt_addr, ntohs(tcp_hdr(skb)->source));
1316 goto drop_and_release;
1317 }
1318
1319 isn = tcp_v6_init_sequence(skb);
1320 }
1321 have_isn:
1322 tcp_rsk(req)->snt_isn = isn;
1323 tcp_rsk(req)->snt_synack = tcp_time_stamp;
1324
1325 security_inet_conn_request(sk, skb, req);
1326
1327 if (tcp_v6_send_synack(sk, req,
1328 (struct request_values *)&tmp_ext) ||
1329 want_cookie)
1330 goto drop_and_free;
1331
1332 inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
1333 return 0;
1334
1335 drop_and_release:
1336 dst_release(dst);
1337 drop_and_free:
1338 reqsk_free(req);
1339 drop:
1340 return 0; /* don't send reset */
1341 }
1342
1343 static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
1344 struct request_sock *req,
1345 struct dst_entry *dst)
1346 {
1347 struct inet6_request_sock *treq;
1348 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
1349 struct tcp6_sock *newtcp6sk;
1350 struct inet_sock *newinet;
1351 struct tcp_sock *newtp;
1352 struct sock *newsk;
1353 struct ipv6_txoptions *opt;
1354 #ifdef CONFIG_TCP_MD5SIG
1355 struct tcp_md5sig_key *key;
1356 #endif
1357
1358 if (skb->protocol == htons(ETH_P_IP)) {
1359 /*
1360 * v6 mapped
1361 */
1362
1363 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst);
1364
1365 if (newsk == NULL)
1366 return NULL;
1367
1368 newtcp6sk = (struct tcp6_sock *)newsk;
1369 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
1370
1371 newinet = inet_sk(newsk);
1372 newnp = inet6_sk(newsk);
1373 newtp = tcp_sk(newsk);
1374
1375 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1376
1377 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr);
1378
1379 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
1380
1381 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
1382
1383 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped;
1384 newsk->sk_backlog_rcv = tcp_v4_do_rcv;
1385 #ifdef CONFIG_TCP_MD5SIG
1386 newtp->af_specific = &tcp_sock_ipv6_mapped_specific;
1387 #endif
1388
1389 newnp->ipv6_ac_list = NULL;
1390 newnp->ipv6_fl_list = NULL;
1391 newnp->pktoptions = NULL;
1392 newnp->opt = NULL;
1393 newnp->mcast_oif = inet6_iif(skb);
1394 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
1395
1396 /*
1397 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1398 * here, tcp_create_openreq_child now does this for us, see the comment in
1399 * that function for the gory details. -acme
1400 */
1401
1402 /* It is tricky place. Until this moment IPv4 tcp
1403 worked with IPv6 icsk.icsk_af_ops.
1404 Sync it now.
1405 */
1406 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
1407
1408 return newsk;
1409 }
1410
1411 treq = inet6_rsk(req);
1412 opt = np->opt;
1413
1414 if (sk_acceptq_is_full(sk))
1415 goto out_overflow;
1416
1417 if (!dst) {
1418 dst = inet6_csk_route_req(sk, req);
1419 if (!dst)
1420 goto out;
1421 }
1422
1423 newsk = tcp_create_openreq_child(sk, req, skb);
1424 if (newsk == NULL)
1425 goto out_nonewsk;
1426
1427 /*
1428 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1429 * count here, tcp_create_openreq_child now does this for us, see the
1430 * comment in that function for the gory details. -acme
1431 */
1432
1433 newsk->sk_gso_type = SKB_GSO_TCPV6;
1434 __ip6_dst_store(newsk, dst, NULL, NULL);
1435
1436 newtcp6sk = (struct tcp6_sock *)newsk;
1437 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
1438
1439 newtp = tcp_sk(newsk);
1440 newinet = inet_sk(newsk);
1441 newnp = inet6_sk(newsk);
1442
1443 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1444
1445 ipv6_addr_copy(&newnp->daddr, &treq->rmt_addr);
1446 ipv6_addr_copy(&newnp->saddr, &treq->loc_addr);
1447 ipv6_addr_copy(&newnp->rcv_saddr, &treq->loc_addr);
1448 newsk->sk_bound_dev_if = treq->iif;
1449
1450 /* Now IPv6 options...
1451
1452 First: no IPv4 options.
1453 */
1454 newinet->inet_opt = NULL;
1455 newnp->ipv6_ac_list = NULL;
1456 newnp->ipv6_fl_list = NULL;
1457
1458 /* Clone RX bits */
1459 newnp->rxopt.all = np->rxopt.all;
1460
1461 /* Clone pktoptions received with SYN */
1462 newnp->pktoptions = NULL;
1463 if (treq->pktopts != NULL) {
1464 newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC);
1465 kfree_skb(treq->pktopts);
1466 treq->pktopts = NULL;
1467 if (newnp->pktoptions)
1468 skb_set_owner_r(newnp->pktoptions, newsk);
1469 }
1470 newnp->opt = NULL;
1471 newnp->mcast_oif = inet6_iif(skb);
1472 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
1473
1474 /* Clone native IPv6 options from listening socket (if any)
1475
1476 Yes, keeping reference count would be much more clever,
1477 but we make one more one thing there: reattach optmem
1478 to newsk.
1479 */
1480 if (opt) {
1481 newnp->opt = ipv6_dup_options(newsk, opt);
1482 if (opt != np->opt)
1483 sock_kfree_s(sk, opt, opt->tot_len);
1484 }
1485
1486 inet_csk(newsk)->icsk_ext_hdr_len = 0;
1487 if (newnp->opt)
1488 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
1489 newnp->opt->opt_flen);
1490
1491 tcp_mtup_init(newsk);
1492 tcp_sync_mss(newsk, dst_mtu(dst));
1493 newtp->advmss = dst_metric_advmss(dst);
1494 tcp_initialize_rcv_mss(newsk);
1495 if (tcp_rsk(req)->snt_synack)
1496 tcp_valid_rtt_meas(newsk,
1497 tcp_time_stamp - tcp_rsk(req)->snt_synack);
1498 newtp->total_retrans = req->retrans;
1499
1500 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
1501 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
1502
1503 #ifdef CONFIG_TCP_MD5SIG
1504 /* Copy over the MD5 key from the original socket */
1505 if ((key = tcp_v6_md5_do_lookup(sk, &newnp->daddr)) != NULL) {
1506 /* We're using one, so create a matching key
1507 * on the newsk structure. If we fail to get
1508 * memory, then we end up not copying the key
1509 * across. Shucks.
1510 */
1511 char *newkey = kmemdup(key->key, key->keylen, GFP_ATOMIC);
1512 if (newkey != NULL)
1513 tcp_v6_md5_do_add(newsk, &newnp->daddr,
1514 newkey, key->keylen);
1515 }
1516 #endif
1517
1518 if (__inet_inherit_port(sk, newsk) < 0) {
1519 sock_put(newsk);
1520 goto out;
1521 }
1522 __inet6_hash(newsk, NULL);
1523
1524 return newsk;
1525
1526 out_overflow:
1527 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
1528 out_nonewsk:
1529 if (opt && opt != np->opt)
1530 sock_kfree_s(sk, opt, opt->tot_len);
1531 dst_release(dst);
1532 out:
1533 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
1534 return NULL;
1535 }
1536
1537 static __sum16 tcp_v6_checksum_init(struct sk_buff *skb)
1538 {
1539 if (skb->ip_summed == CHECKSUM_COMPLETE) {
1540 if (!tcp_v6_check(skb->len, &ipv6_hdr(skb)->saddr,
1541 &ipv6_hdr(skb)->daddr, skb->csum)) {
1542 skb->ip_summed = CHECKSUM_UNNECESSARY;
1543 return 0;
1544 }
1545 }
1546
1547 skb->csum = ~csum_unfold(tcp_v6_check(skb->len,
1548 &ipv6_hdr(skb)->saddr,
1549 &ipv6_hdr(skb)->daddr, 0));
1550
1551 if (skb->len <= 76) {
1552 return __skb_checksum_complete(skb);
1553 }
1554 return 0;
1555 }
1556
1557 /* The socket must have it's spinlock held when we get
1558 * here.
1559 *
1560 * We have a potential double-lock case here, so even when
1561 * doing backlog processing we use the BH locking scheme.
1562 * This is because we cannot sleep with the original spinlock
1563 * held.
1564 */
1565 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
1566 {
1567 struct ipv6_pinfo *np = inet6_sk(sk);
1568 struct tcp_sock *tp;
1569 struct sk_buff *opt_skb = NULL;
1570
1571 /* Imagine: socket is IPv6. IPv4 packet arrives,
1572 goes to IPv4 receive handler and backlogged.
1573 From backlog it always goes here. Kerboom...
1574 Fortunately, tcp_rcv_established and rcv_established
1575 handle them correctly, but it is not case with
1576 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1577 */
1578
1579 if (skb->protocol == htons(ETH_P_IP))
1580 return tcp_v4_do_rcv(sk, skb);
1581
1582 #ifdef CONFIG_TCP_MD5SIG
1583 if (tcp_v6_inbound_md5_hash (sk, skb))
1584 goto discard;
1585 #endif
1586
1587 if (sk_filter(sk, skb))
1588 goto discard;
1589
1590 /*
1591 * socket locking is here for SMP purposes as backlog rcv
1592 * is currently called with bh processing disabled.
1593 */
1594
1595 /* Do Stevens' IPV6_PKTOPTIONS.
1596
1597 Yes, guys, it is the only place in our code, where we
1598 may make it not affecting IPv4.
1599 The rest of code is protocol independent,
1600 and I do not like idea to uglify IPv4.
1601
1602 Actually, all the idea behind IPV6_PKTOPTIONS
1603 looks not very well thought. For now we latch
1604 options, received in the last packet, enqueued
1605 by tcp. Feel free to propose better solution.
1606 --ANK (980728)
1607 */
1608 if (np->rxopt.all)
1609 opt_skb = skb_clone(skb, GFP_ATOMIC);
1610
1611 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
1612 sock_rps_save_rxhash(sk, skb);
1613 if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len))
1614 goto reset;
1615 if (opt_skb)
1616 goto ipv6_pktoptions;
1617 return 0;
1618 }
1619
1620 if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb))
1621 goto csum_err;
1622
1623 if (sk->sk_state == TCP_LISTEN) {
1624 struct sock *nsk = tcp_v6_hnd_req(sk, skb);
1625 if (!nsk)
1626 goto discard;
1627
1628 /*
1629 * Queue it on the new socket if the new socket is active,
1630 * otherwise we just shortcircuit this and continue with
1631 * the new socket..
1632 */
1633 if(nsk != sk) {
1634 sock_rps_save_rxhash(nsk, skb);
1635 if (tcp_child_process(sk, nsk, skb))
1636 goto reset;
1637 if (opt_skb)
1638 __kfree_skb(opt_skb);
1639 return 0;
1640 }
1641 } else
1642 sock_rps_save_rxhash(sk, skb);
1643
1644 if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len))
1645 goto reset;
1646 if (opt_skb)
1647 goto ipv6_pktoptions;
1648 return 0;
1649
1650 reset:
1651 tcp_v6_send_reset(sk, skb);
1652 discard:
1653 if (opt_skb)
1654 __kfree_skb(opt_skb);
1655 kfree_skb(skb);
1656 return 0;
1657 csum_err:
1658 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);
1659 goto discard;
1660
1661
1662 ipv6_pktoptions:
1663 /* Do you ask, what is it?
1664
1665 1. skb was enqueued by tcp.
1666 2. skb is added to tail of read queue, rather than out of order.
1667 3. socket is not in passive state.
1668 4. Finally, it really contains options, which user wants to receive.
1669 */
1670 tp = tcp_sk(sk);
1671 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
1672 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
1673 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
1674 np->mcast_oif = inet6_iif(opt_skb);
1675 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
1676 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
1677 if (ipv6_opt_accepted(sk, opt_skb)) {
1678 skb_set_owner_r(opt_skb, sk);
1679 opt_skb = xchg(&np->pktoptions, opt_skb);
1680 } else {
1681 __kfree_skb(opt_skb);
1682 opt_skb = xchg(&np->pktoptions, NULL);
1683 }
1684 }
1685
1686 kfree_skb(opt_skb);
1687 return 0;
1688 }
1689
1690 static int tcp_v6_rcv(struct sk_buff *skb)
1691 {
1692 const struct tcphdr *th;
1693 const struct ipv6hdr *hdr;
1694 struct sock *sk;
1695 int ret;
1696 struct net *net = dev_net(skb->dev);
1697
1698 if (skb->pkt_type != PACKET_HOST)
1699 goto discard_it;
1700
1701 /*
1702 * Count it even if it's bad.
1703 */
1704 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS);
1705
1706 if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
1707 goto discard_it;
1708
1709 th = tcp_hdr(skb);
1710
1711 if (th->doff < sizeof(struct tcphdr)/4)
1712 goto bad_packet;
1713 if (!pskb_may_pull(skb, th->doff*4))
1714 goto discard_it;
1715
1716 if (!skb_csum_unnecessary(skb) && tcp_v6_checksum_init(skb))
1717 goto bad_packet;
1718
1719 th = tcp_hdr(skb);
1720 hdr = ipv6_hdr(skb);
1721 TCP_SKB_CB(skb)->seq = ntohl(th->seq);
1722 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
1723 skb->len - th->doff*4);
1724 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
1725 TCP_SKB_CB(skb)->when = 0;
1726 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr);
1727 TCP_SKB_CB(skb)->sacked = 0;
1728
1729 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest);
1730 if (!sk)
1731 goto no_tcp_socket;
1732
1733 process:
1734 if (sk->sk_state == TCP_TIME_WAIT)
1735 goto do_time_wait;
1736
1737 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) {
1738 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
1739 goto discard_and_relse;
1740 }
1741
1742 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
1743 goto discard_and_relse;
1744
1745 if (sk_filter(sk, skb))
1746 goto discard_and_relse;
1747
1748 skb->dev = NULL;
1749
1750 bh_lock_sock_nested(sk);
1751 ret = 0;
1752 if (!sock_owned_by_user(sk)) {
1753 #ifdef CONFIG_NET_DMA
1754 struct tcp_sock *tp = tcp_sk(sk);
1755 if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
1756 tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
1757 if (tp->ucopy.dma_chan)
1758 ret = tcp_v6_do_rcv(sk, skb);
1759 else
1760 #endif
1761 {
1762 if (!tcp_prequeue(sk, skb))
1763 ret = tcp_v6_do_rcv(sk, skb);
1764 }
1765 } else if (unlikely(sk_add_backlog(sk, skb))) {
1766 bh_unlock_sock(sk);
1767 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP);
1768 goto discard_and_relse;
1769 }
1770 bh_unlock_sock(sk);
1771
1772 sock_put(sk);
1773 return ret ? -1 : 0;
1774
1775 no_tcp_socket:
1776 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1777 goto discard_it;
1778
1779 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1780 bad_packet:
1781 TCP_INC_STATS_BH(net, TCP_MIB_INERRS);
1782 } else {
1783 tcp_v6_send_reset(NULL, skb);
1784 }
1785
1786 discard_it:
1787
1788 /*
1789 * Discard frame
1790 */
1791
1792 kfree_skb(skb);
1793 return 0;
1794
1795 discard_and_relse:
1796 sock_put(sk);
1797 goto discard_it;
1798
1799 do_time_wait:
1800 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1801 inet_twsk_put(inet_twsk(sk));
1802 goto discard_it;
1803 }
1804
1805 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1806 TCP_INC_STATS_BH(net, TCP_MIB_INERRS);
1807 inet_twsk_put(inet_twsk(sk));
1808 goto discard_it;
1809 }
1810
1811 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) {
1812 case TCP_TW_SYN:
1813 {
1814 struct sock *sk2;
1815
1816 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo,
1817 &ipv6_hdr(skb)->daddr,
1818 ntohs(th->dest), inet6_iif(skb));
1819 if (sk2 != NULL) {
1820 struct inet_timewait_sock *tw = inet_twsk(sk);
1821 inet_twsk_deschedule(tw, &tcp_death_row);
1822 inet_twsk_put(tw);
1823 sk = sk2;
1824 goto process;
1825 }
1826 /* Fall through to ACK */
1827 }
1828 case TCP_TW_ACK:
1829 tcp_v6_timewait_ack(sk, skb);
1830 break;
1831 case TCP_TW_RST:
1832 goto no_tcp_socket;
1833 case TCP_TW_SUCCESS:;
1834 }
1835 goto discard_it;
1836 }
1837
1838 static struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it)
1839 {
1840 struct rt6_info *rt = (struct rt6_info *) __sk_dst_get(sk);
1841 struct ipv6_pinfo *np = inet6_sk(sk);
1842 struct inet_peer *peer;
1843
1844 if (!rt ||
1845 !ipv6_addr_equal(&np->daddr, &rt->rt6i_dst.addr)) {
1846 peer = inet_getpeer_v6(&np->daddr, 1);
1847 *release_it = true;
1848 } else {
1849 if (!rt->rt6i_peer)
1850 rt6_bind_peer(rt, 1);
1851 peer = rt->rt6i_peer;
1852 *release_it = false;
1853 }
1854
1855 return peer;
1856 }
1857
1858 static void *tcp_v6_tw_get_peer(struct sock *sk)
1859 {
1860 const struct inet6_timewait_sock *tw6 = inet6_twsk(sk);
1861 const struct inet_timewait_sock *tw = inet_twsk(sk);
1862
1863 if (tw->tw_family == AF_INET)
1864 return tcp_v4_tw_get_peer(sk);
1865
1866 return inet_getpeer_v6(&tw6->tw_v6_daddr, 1);
1867 }
1868
1869 static struct timewait_sock_ops tcp6_timewait_sock_ops = {
1870 .twsk_obj_size = sizeof(struct tcp6_timewait_sock),
1871 .twsk_unique = tcp_twsk_unique,
1872 .twsk_destructor= tcp_twsk_destructor,
1873 .twsk_getpeer = tcp_v6_tw_get_peer,
1874 };
1875
1876 static const struct inet_connection_sock_af_ops ipv6_specific = {
1877 .queue_xmit = inet6_csk_xmit,
1878 .send_check = tcp_v6_send_check,
1879 .rebuild_header = inet6_sk_rebuild_header,
1880 .conn_request = tcp_v6_conn_request,
1881 .syn_recv_sock = tcp_v6_syn_recv_sock,
1882 .get_peer = tcp_v6_get_peer,
1883 .net_header_len = sizeof(struct ipv6hdr),
1884 .setsockopt = ipv6_setsockopt,
1885 .getsockopt = ipv6_getsockopt,
1886 .addr2sockaddr = inet6_csk_addr2sockaddr,
1887 .sockaddr_len = sizeof(struct sockaddr_in6),
1888 .bind_conflict = inet6_csk_bind_conflict,
1889 #ifdef CONFIG_COMPAT
1890 .compat_setsockopt = compat_ipv6_setsockopt,
1891 .compat_getsockopt = compat_ipv6_getsockopt,
1892 #endif
1893 };
1894
1895 #ifdef CONFIG_TCP_MD5SIG
1896 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = {
1897 .md5_lookup = tcp_v6_md5_lookup,
1898 .calc_md5_hash = tcp_v6_md5_hash_skb,
1899 .md5_add = tcp_v6_md5_add_func,
1900 .md5_parse = tcp_v6_parse_md5_keys,
1901 };
1902 #endif
1903
1904 /*
1905 * TCP over IPv4 via INET6 API
1906 */
1907
1908 static const struct inet_connection_sock_af_ops ipv6_mapped = {
1909 .queue_xmit = ip_queue_xmit,
1910 .send_check = tcp_v4_send_check,
1911 .rebuild_header = inet_sk_rebuild_header,
1912 .conn_request = tcp_v6_conn_request,
1913 .syn_recv_sock = tcp_v6_syn_recv_sock,
1914 .get_peer = tcp_v4_get_peer,
1915 .net_header_len = sizeof(struct iphdr),
1916 .setsockopt = ipv6_setsockopt,
1917 .getsockopt = ipv6_getsockopt,
1918 .addr2sockaddr = inet6_csk_addr2sockaddr,
1919 .sockaddr_len = sizeof(struct sockaddr_in6),
1920 .bind_conflict = inet6_csk_bind_conflict,
1921 #ifdef CONFIG_COMPAT
1922 .compat_setsockopt = compat_ipv6_setsockopt,
1923 .compat_getsockopt = compat_ipv6_getsockopt,
1924 #endif
1925 };
1926
1927 #ifdef CONFIG_TCP_MD5SIG
1928 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = {
1929 .md5_lookup = tcp_v4_md5_lookup,
1930 .calc_md5_hash = tcp_v4_md5_hash_skb,
1931 .md5_add = tcp_v6_md5_add_func,
1932 .md5_parse = tcp_v6_parse_md5_keys,
1933 };
1934 #endif
1935
1936 /* NOTE: A lot of things set to zero explicitly by call to
1937 * sk_alloc() so need not be done here.
1938 */
1939 static int tcp_v6_init_sock(struct sock *sk)
1940 {
1941 struct inet_connection_sock *icsk = inet_csk(sk);
1942 struct tcp_sock *tp = tcp_sk(sk);
1943
1944 skb_queue_head_init(&tp->out_of_order_queue);
1945 tcp_init_xmit_timers(sk);
1946 tcp_prequeue_init(tp);
1947
1948 icsk->icsk_rto = TCP_TIMEOUT_INIT;
1949 tp->mdev = TCP_TIMEOUT_INIT;
1950
1951 /* So many TCP implementations out there (incorrectly) count the
1952 * initial SYN frame in their delayed-ACK and congestion control
1953 * algorithms that we must have the following bandaid to talk
1954 * efficiently to them. -DaveM
1955 */
1956 tp->snd_cwnd = 2;
1957
1958 /* See draft-stevens-tcpca-spec-01 for discussion of the
1959 * initialization of these values.
1960 */
1961 tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
1962 tp->snd_cwnd_clamp = ~0;
1963 tp->mss_cache = TCP_MSS_DEFAULT;
1964
1965 tp->reordering = sysctl_tcp_reordering;
1966
1967 sk->sk_state = TCP_CLOSE;
1968
1969 icsk->icsk_af_ops = &ipv6_specific;
1970 icsk->icsk_ca_ops = &tcp_init_congestion_ops;
1971 icsk->icsk_sync_mss = tcp_sync_mss;
1972 sk->sk_write_space = sk_stream_write_space;
1973 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
1974
1975 #ifdef CONFIG_TCP_MD5SIG
1976 tp->af_specific = &tcp_sock_ipv6_specific;
1977 #endif
1978
1979 /* TCP Cookie Transactions */
1980 if (sysctl_tcp_cookie_size > 0) {
1981 /* Default, cookies without s_data_payload. */
1982 tp->cookie_values =
1983 kzalloc(sizeof(*tp->cookie_values),
1984 sk->sk_allocation);
1985 if (tp->cookie_values != NULL)
1986 kref_init(&tp->cookie_values->kref);
1987 }
1988 /* Presumed zeroed, in order of appearance:
1989 * cookie_in_always, cookie_out_never,
1990 * s_data_constant, s_data_in, s_data_out
1991 */
1992 sk->sk_sndbuf = sysctl_tcp_wmem[1];
1993 sk->sk_rcvbuf = sysctl_tcp_rmem[1];
1994
1995 local_bh_disable();
1996 percpu_counter_inc(&tcp_sockets_allocated);
1997 local_bh_enable();
1998
1999 return 0;
2000 }
2001
2002 static void tcp_v6_destroy_sock(struct sock *sk)
2003 {
2004 #ifdef CONFIG_TCP_MD5SIG
2005 /* Clean up the MD5 key list */
2006 if (tcp_sk(sk)->md5sig_info)
2007 tcp_v6_clear_md5_list(sk);
2008 #endif
2009 tcp_v4_destroy_sock(sk);
2010 inet6_destroy_sock(sk);
2011 }
2012
2013 #ifdef CONFIG_PROC_FS
2014 /* Proc filesystem TCPv6 sock list dumping. */
2015 static void get_openreq6(struct seq_file *seq,
2016 const struct sock *sk, struct request_sock *req, int i, int uid)
2017 {
2018 int ttd = req->expires - jiffies;
2019 const struct in6_addr *src = &inet6_rsk(req)->loc_addr;
2020 const struct in6_addr *dest = &inet6_rsk(req)->rmt_addr;
2021
2022 if (ttd < 0)
2023 ttd = 0;
2024
2025 seq_printf(seq,
2026 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2027 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
2028 i,
2029 src->s6_addr32[0], src->s6_addr32[1],
2030 src->s6_addr32[2], src->s6_addr32[3],
2031 ntohs(inet_rsk(req)->loc_port),
2032 dest->s6_addr32[0], dest->s6_addr32[1],
2033 dest->s6_addr32[2], dest->s6_addr32[3],
2034 ntohs(inet_rsk(req)->rmt_port),
2035 TCP_SYN_RECV,
2036 0,0, /* could print option size, but that is af dependent. */
2037 1, /* timers active (only the expire timer) */
2038 jiffies_to_clock_t(ttd),
2039 req->retrans,
2040 uid,
2041 0, /* non standard timer */
2042 0, /* open_requests have no inode */
2043 0, req);
2044 }
2045
2046 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
2047 {
2048 const struct in6_addr *dest, *src;
2049 __u16 destp, srcp;
2050 int timer_active;
2051 unsigned long timer_expires;
2052 const struct inet_sock *inet = inet_sk(sp);
2053 const struct tcp_sock *tp = tcp_sk(sp);
2054 const struct inet_connection_sock *icsk = inet_csk(sp);
2055 const struct ipv6_pinfo *np = inet6_sk(sp);
2056
2057 dest = &np->daddr;
2058 src = &np->rcv_saddr;
2059 destp = ntohs(inet->inet_dport);
2060 srcp = ntohs(inet->inet_sport);
2061
2062 if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
2063 timer_active = 1;
2064 timer_expires = icsk->icsk_timeout;
2065 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
2066 timer_active = 4;
2067 timer_expires = icsk->icsk_timeout;
2068 } else if (timer_pending(&sp->sk_timer)) {
2069 timer_active = 2;
2070 timer_expires = sp->sk_timer.expires;
2071 } else {
2072 timer_active = 0;
2073 timer_expires = jiffies;
2074 }
2075
2076 seq_printf(seq,
2077 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2078 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %lu %lu %u %u %d\n",
2079 i,
2080 src->s6_addr32[0], src->s6_addr32[1],
2081 src->s6_addr32[2], src->s6_addr32[3], srcp,
2082 dest->s6_addr32[0], dest->s6_addr32[1],
2083 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2084 sp->sk_state,
2085 tp->write_seq-tp->snd_una,
2086 (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq),
2087 timer_active,
2088 jiffies_to_clock_t(timer_expires - jiffies),
2089 icsk->icsk_retransmits,
2090 sock_i_uid(sp),
2091 icsk->icsk_probes_out,
2092 sock_i_ino(sp),
2093 atomic_read(&sp->sk_refcnt), sp,
2094 jiffies_to_clock_t(icsk->icsk_rto),
2095 jiffies_to_clock_t(icsk->icsk_ack.ato),
2096 (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong,
2097 tp->snd_cwnd,
2098 tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh
2099 );
2100 }
2101
2102 static void get_timewait6_sock(struct seq_file *seq,
2103 struct inet_timewait_sock *tw, int i)
2104 {
2105 const struct in6_addr *dest, *src;
2106 __u16 destp, srcp;
2107 const struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw);
2108 int ttd = tw->tw_ttd - jiffies;
2109
2110 if (ttd < 0)
2111 ttd = 0;
2112
2113 dest = &tw6->tw_v6_daddr;
2114 src = &tw6->tw_v6_rcv_saddr;
2115 destp = ntohs(tw->tw_dport);
2116 srcp = ntohs(tw->tw_sport);
2117
2118 seq_printf(seq,
2119 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2120 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
2121 i,
2122 src->s6_addr32[0], src->s6_addr32[1],
2123 src->s6_addr32[2], src->s6_addr32[3], srcp,
2124 dest->s6_addr32[0], dest->s6_addr32[1],
2125 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2126 tw->tw_substate, 0, 0,
2127 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0,
2128 atomic_read(&tw->tw_refcnt), tw);
2129 }
2130
2131 static int tcp6_seq_show(struct seq_file *seq, void *v)
2132 {
2133 struct tcp_iter_state *st;
2134
2135 if (v == SEQ_START_TOKEN) {
2136 seq_puts(seq,
2137 " sl "
2138 "local_address "
2139 "remote_address "
2140 "st tx_queue rx_queue tr tm->when retrnsmt"
2141 " uid timeout inode\n");
2142 goto out;
2143 }
2144 st = seq->private;
2145
2146 switch (st->state) {
2147 case TCP_SEQ_STATE_LISTENING:
2148 case TCP_SEQ_STATE_ESTABLISHED:
2149 get_tcp6_sock(seq, v, st->num);
2150 break;
2151 case TCP_SEQ_STATE_OPENREQ:
2152 get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid);
2153 break;
2154 case TCP_SEQ_STATE_TIME_WAIT:
2155 get_timewait6_sock(seq, v, st->num);
2156 break;
2157 }
2158 out:
2159 return 0;
2160 }
2161
2162 static struct tcp_seq_afinfo tcp6_seq_afinfo = {
2163 .name = "tcp6",
2164 .family = AF_INET6,
2165 .seq_fops = {
2166 .owner = THIS_MODULE,
2167 },
2168 .seq_ops = {
2169 .show = tcp6_seq_show,
2170 },
2171 };
2172
2173 int __net_init tcp6_proc_init(struct net *net)
2174 {
2175 return tcp_proc_register(net, &tcp6_seq_afinfo);
2176 }
2177
2178 void tcp6_proc_exit(struct net *net)
2179 {
2180 tcp_proc_unregister(net, &tcp6_seq_afinfo);
2181 }
2182 #endif
2183
2184 struct proto tcpv6_prot = {
2185 .name = "TCPv6",
2186 .owner = THIS_MODULE,
2187 .close = tcp_close,
2188 .connect = tcp_v6_connect,
2189 .disconnect = tcp_disconnect,
2190 .accept = inet_csk_accept,
2191 .ioctl = tcp_ioctl,
2192 .init = tcp_v6_init_sock,
2193 .destroy = tcp_v6_destroy_sock,
2194 .shutdown = tcp_shutdown,
2195 .setsockopt = tcp_setsockopt,
2196 .getsockopt = tcp_getsockopt,
2197 .recvmsg = tcp_recvmsg,
2198 .sendmsg = tcp_sendmsg,
2199 .sendpage = tcp_sendpage,
2200 .backlog_rcv = tcp_v6_do_rcv,
2201 .hash = tcp_v6_hash,
2202 .unhash = inet_unhash,
2203 .get_port = inet_csk_get_port,
2204 .enter_memory_pressure = tcp_enter_memory_pressure,
2205 .sockets_allocated = &tcp_sockets_allocated,
2206 .memory_allocated = &tcp_memory_allocated,
2207 .memory_pressure = &tcp_memory_pressure,
2208 .orphan_count = &tcp_orphan_count,
2209 .sysctl_mem = sysctl_tcp_mem,
2210 .sysctl_wmem = sysctl_tcp_wmem,
2211 .sysctl_rmem = sysctl_tcp_rmem,
2212 .max_header = MAX_TCP_HEADER,
2213 .obj_size = sizeof(struct tcp6_sock),
2214 .slab_flags = SLAB_DESTROY_BY_RCU,
2215 .twsk_prot = &tcp6_timewait_sock_ops,
2216 .rsk_prot = &tcp6_request_sock_ops,
2217 .h.hashinfo = &tcp_hashinfo,
2218 .no_autobind = true,
2219 #ifdef CONFIG_COMPAT
2220 .compat_setsockopt = compat_tcp_setsockopt,
2221 .compat_getsockopt = compat_tcp_getsockopt,
2222 #endif
2223 };
2224
2225 static const struct inet6_protocol tcpv6_protocol = {
2226 .handler = tcp_v6_rcv,
2227 .err_handler = tcp_v6_err,
2228 .gso_send_check = tcp_v6_gso_send_check,
2229 .gso_segment = tcp_tso_segment,
2230 .gro_receive = tcp6_gro_receive,
2231 .gro_complete = tcp6_gro_complete,
2232 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
2233 };
2234
2235 static struct inet_protosw tcpv6_protosw = {
2236 .type = SOCK_STREAM,
2237 .protocol = IPPROTO_TCP,
2238 .prot = &tcpv6_prot,
2239 .ops = &inet6_stream_ops,
2240 .no_check = 0,
2241 .flags = INET_PROTOSW_PERMANENT |
2242 INET_PROTOSW_ICSK,
2243 };
2244
2245 static int __net_init tcpv6_net_init(struct net *net)
2246 {
2247 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6,
2248 SOCK_RAW, IPPROTO_TCP, net);
2249 }
2250
2251 static void __net_exit tcpv6_net_exit(struct net *net)
2252 {
2253 inet_ctl_sock_destroy(net->ipv6.tcp_sk);
2254 }
2255
2256 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
2257 {
2258 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6);
2259 }
2260
2261 static struct pernet_operations tcpv6_net_ops = {
2262 .init = tcpv6_net_init,
2263 .exit = tcpv6_net_exit,
2264 .exit_batch = tcpv6_net_exit_batch,
2265 };
2266
2267 int __init tcpv6_init(void)
2268 {
2269 int ret;
2270
2271 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP);
2272 if (ret)
2273 goto out;
2274
2275 /* register inet6 protocol */
2276 ret = inet6_register_protosw(&tcpv6_protosw);
2277 if (ret)
2278 goto out_tcpv6_protocol;
2279
2280 ret = register_pernet_subsys(&tcpv6_net_ops);
2281 if (ret)
2282 goto out_tcpv6_protosw;
2283 out:
2284 return ret;
2285
2286 out_tcpv6_protocol:
2287 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);
2288 out_tcpv6_protosw:
2289 inet6_unregister_protosw(&tcpv6_protosw);
2290 goto out;
2291 }
2292
2293 void tcpv6_exit(void)
2294 {
2295 unregister_pernet_subsys(&tcpv6_net_ops);
2296 inet6_unregister_protosw(&tcpv6_protosw);
2297 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);
2298 }
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree