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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * Implementation of the Transmission Control Protocol(TCP). | |
7 | * | |
8 | * Version: $Id: tcp_ipv4.c,v 1.240 2002/02/01 22:01:04 davem Exp $ | |
9 | * | |
10 | * IPv4 specific functions | |
11 | * | |
12 | * | |
13 | * code split from: | |
14 | * linux/ipv4/tcp.c | |
15 | * linux/ipv4/tcp_input.c | |
16 | * linux/ipv4/tcp_output.c | |
17 | * | |
18 | * See tcp.c for author information | |
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 | /* | |
27 | * Changes: | |
28 | * David S. Miller : New socket lookup architecture. | |
29 | * This code is dedicated to John Dyson. | |
30 | * David S. Miller : Change semantics of established hash, | |
31 | * half is devoted to TIME_WAIT sockets | |
32 | * and the rest go in the other half. | |
33 | * Andi Kleen : Add support for syncookies and fixed | |
34 | * some bugs: ip options weren't passed to | |
35 | * the TCP layer, missed a check for an | |
36 | * ACK bit. | |
37 | * Andi Kleen : Implemented fast path mtu discovery. | |
38 | * Fixed many serious bugs in the | |
60236fdd | 39 | * request_sock handling and moved |
1da177e4 LT |
40 | * most of it into the af independent code. |
41 | * Added tail drop and some other bugfixes. | |
caa20d9a | 42 | * Added new listen semantics. |
1da177e4 LT |
43 | * Mike McLagan : Routing by source |
44 | * Juan Jose Ciarlante: ip_dynaddr bits | |
45 | * Andi Kleen: various fixes. | |
46 | * Vitaly E. Lavrov : Transparent proxy revived after year | |
47 | * coma. | |
48 | * Andi Kleen : Fix new listen. | |
49 | * Andi Kleen : Fix accept error reporting. | |
50 | * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which | |
51 | * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind | |
52 | * a single port at the same time. | |
53 | */ | |
54 | ||
1da177e4 LT |
55 | |
56 | #include <linux/types.h> | |
57 | #include <linux/fcntl.h> | |
58 | #include <linux/module.h> | |
59 | #include <linux/random.h> | |
60 | #include <linux/cache.h> | |
61 | #include <linux/jhash.h> | |
62 | #include <linux/init.h> | |
63 | #include <linux/times.h> | |
64 | ||
65 | #include <net/icmp.h> | |
304a1618 | 66 | #include <net/inet_hashtables.h> |
1da177e4 | 67 | #include <net/tcp.h> |
20380731 | 68 | #include <net/transp_v6.h> |
1da177e4 LT |
69 | #include <net/ipv6.h> |
70 | #include <net/inet_common.h> | |
6d6ee43e | 71 | #include <net/timewait_sock.h> |
1da177e4 | 72 | #include <net/xfrm.h> |
1a2449a8 | 73 | #include <net/netdma.h> |
1da177e4 LT |
74 | |
75 | #include <linux/inet.h> | |
76 | #include <linux/ipv6.h> | |
77 | #include <linux/stddef.h> | |
78 | #include <linux/proc_fs.h> | |
79 | #include <linux/seq_file.h> | |
80 | ||
cfb6eeb4 YH |
81 | #include <linux/crypto.h> |
82 | #include <linux/scatterlist.h> | |
83 | ||
ab32ea5d BH |
84 | int sysctl_tcp_tw_reuse __read_mostly; |
85 | int sysctl_tcp_low_latency __read_mostly; | |
1da177e4 LT |
86 | |
87 | /* Check TCP sequence numbers in ICMP packets. */ | |
88 | #define ICMP_MIN_LENGTH 8 | |
89 | ||
90 | /* Socket used for sending RSTs */ | |
91 | static struct socket *tcp_socket; | |
92 | ||
8292a17a | 93 | void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb); |
1da177e4 | 94 | |
cfb6eeb4 YH |
95 | #ifdef CONFIG_TCP_MD5SIG |
96 | static struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, __be32 addr); | |
97 | static int tcp_v4_do_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key, | |
98 | __be32 saddr, __be32 daddr, struct tcphdr *th, | |
99 | int protocol, int tcplen); | |
100 | #endif | |
101 | ||
0f7ff927 | 102 | struct inet_hashinfo __cacheline_aligned tcp_hashinfo = { |
e4d91918 | 103 | .lhash_lock = __RW_LOCK_UNLOCKED(tcp_hashinfo.lhash_lock), |
0f7ff927 ACM |
104 | .lhash_users = ATOMIC_INIT(0), |
105 | .lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(tcp_hashinfo.lhash_wait), | |
1da177e4 LT |
106 | }; |
107 | ||
463c84b9 ACM |
108 | static int tcp_v4_get_port(struct sock *sk, unsigned short snum) |
109 | { | |
971af18b ACM |
110 | return inet_csk_get_port(&tcp_hashinfo, sk, snum, |
111 | inet_csk_bind_conflict); | |
463c84b9 ACM |
112 | } |
113 | ||
1da177e4 LT |
114 | static void tcp_v4_hash(struct sock *sk) |
115 | { | |
81849d10 | 116 | inet_hash(&tcp_hashinfo, sk); |
1da177e4 LT |
117 | } |
118 | ||
119 | void tcp_unhash(struct sock *sk) | |
120 | { | |
81849d10 | 121 | inet_unhash(&tcp_hashinfo, sk); |
1da177e4 LT |
122 | } |
123 | ||
a94f723d | 124 | static inline __u32 tcp_v4_init_sequence(struct sk_buff *skb) |
1da177e4 LT |
125 | { |
126 | return secure_tcp_sequence_number(skb->nh.iph->daddr, | |
127 | skb->nh.iph->saddr, | |
128 | skb->h.th->dest, | |
129 | skb->h.th->source); | |
130 | } | |
131 | ||
6d6ee43e ACM |
132 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) |
133 | { | |
134 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); | |
135 | struct tcp_sock *tp = tcp_sk(sk); | |
136 | ||
137 | /* With PAWS, it is safe from the viewpoint | |
138 | of data integrity. Even without PAWS it is safe provided sequence | |
139 | spaces do not overlap i.e. at data rates <= 80Mbit/sec. | |
140 | ||
141 | Actually, the idea is close to VJ's one, only timestamp cache is | |
142 | held not per host, but per port pair and TW bucket is used as state | |
143 | holder. | |
144 | ||
145 | If TW bucket has been already destroyed we fall back to VJ's scheme | |
146 | and use initial timestamp retrieved from peer table. | |
147 | */ | |
148 | if (tcptw->tw_ts_recent_stamp && | |
149 | (twp == NULL || (sysctl_tcp_tw_reuse && | |
150 | xtime.tv_sec - tcptw->tw_ts_recent_stamp > 1))) { | |
151 | tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; | |
152 | if (tp->write_seq == 0) | |
153 | tp->write_seq = 1; | |
154 | tp->rx_opt.ts_recent = tcptw->tw_ts_recent; | |
155 | tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; | |
156 | sock_hold(sktw); | |
157 | return 1; | |
158 | } | |
159 | ||
160 | return 0; | |
161 | } | |
162 | ||
163 | EXPORT_SYMBOL_GPL(tcp_twsk_unique); | |
164 | ||
1da177e4 LT |
165 | /* This will initiate an outgoing connection. */ |
166 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
167 | { | |
168 | struct inet_sock *inet = inet_sk(sk); | |
169 | struct tcp_sock *tp = tcp_sk(sk); | |
170 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; | |
171 | struct rtable *rt; | |
bada8adc | 172 | __be32 daddr, nexthop; |
1da177e4 LT |
173 | int tmp; |
174 | int err; | |
175 | ||
176 | if (addr_len < sizeof(struct sockaddr_in)) | |
177 | return -EINVAL; | |
178 | ||
179 | if (usin->sin_family != AF_INET) | |
180 | return -EAFNOSUPPORT; | |
181 | ||
182 | nexthop = daddr = usin->sin_addr.s_addr; | |
183 | if (inet->opt && inet->opt->srr) { | |
184 | if (!daddr) | |
185 | return -EINVAL; | |
186 | nexthop = inet->opt->faddr; | |
187 | } | |
188 | ||
189 | tmp = ip_route_connect(&rt, nexthop, inet->saddr, | |
190 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, | |
191 | IPPROTO_TCP, | |
192 | inet->sport, usin->sin_port, sk); | |
193 | if (tmp < 0) | |
194 | return tmp; | |
195 | ||
196 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
197 | ip_rt_put(rt); | |
198 | return -ENETUNREACH; | |
199 | } | |
200 | ||
201 | if (!inet->opt || !inet->opt->srr) | |
202 | daddr = rt->rt_dst; | |
203 | ||
204 | if (!inet->saddr) | |
205 | inet->saddr = rt->rt_src; | |
206 | inet->rcv_saddr = inet->saddr; | |
207 | ||
208 | if (tp->rx_opt.ts_recent_stamp && inet->daddr != daddr) { | |
209 | /* Reset inherited state */ | |
210 | tp->rx_opt.ts_recent = 0; | |
211 | tp->rx_opt.ts_recent_stamp = 0; | |
212 | tp->write_seq = 0; | |
213 | } | |
214 | ||
295ff7ed | 215 | if (tcp_death_row.sysctl_tw_recycle && |
1da177e4 LT |
216 | !tp->rx_opt.ts_recent_stamp && rt->rt_dst == daddr) { |
217 | struct inet_peer *peer = rt_get_peer(rt); | |
218 | ||
219 | /* VJ's idea. We save last timestamp seen from | |
220 | * the destination in peer table, when entering state TIME-WAIT | |
221 | * and initialize rx_opt.ts_recent from it, when trying new connection. | |
222 | */ | |
223 | ||
224 | if (peer && peer->tcp_ts_stamp + TCP_PAWS_MSL >= xtime.tv_sec) { | |
225 | tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp; | |
226 | tp->rx_opt.ts_recent = peer->tcp_ts; | |
227 | } | |
228 | } | |
229 | ||
230 | inet->dport = usin->sin_port; | |
231 | inet->daddr = daddr; | |
232 | ||
d83d8461 | 233 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
1da177e4 | 234 | if (inet->opt) |
d83d8461 | 235 | inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; |
1da177e4 LT |
236 | |
237 | tp->rx_opt.mss_clamp = 536; | |
238 | ||
239 | /* Socket identity is still unknown (sport may be zero). | |
240 | * However we set state to SYN-SENT and not releasing socket | |
241 | * lock select source port, enter ourselves into the hash tables and | |
242 | * complete initialization after this. | |
243 | */ | |
244 | tcp_set_state(sk, TCP_SYN_SENT); | |
a7f5e7f1 | 245 | err = inet_hash_connect(&tcp_death_row, sk); |
1da177e4 LT |
246 | if (err) |
247 | goto failure; | |
248 | ||
5d39a795 | 249 | err = ip_route_newports(&rt, IPPROTO_TCP, inet->sport, inet->dport, sk); |
1da177e4 LT |
250 | if (err) |
251 | goto failure; | |
252 | ||
253 | /* OK, now commit destination to socket. */ | |
bcd76111 | 254 | sk->sk_gso_type = SKB_GSO_TCPV4; |
6cbb0df7 | 255 | sk_setup_caps(sk, &rt->u.dst); |
1da177e4 LT |
256 | |
257 | if (!tp->write_seq) | |
258 | tp->write_seq = secure_tcp_sequence_number(inet->saddr, | |
259 | inet->daddr, | |
260 | inet->sport, | |
261 | usin->sin_port); | |
262 | ||
263 | inet->id = tp->write_seq ^ jiffies; | |
264 | ||
265 | err = tcp_connect(sk); | |
266 | rt = NULL; | |
267 | if (err) | |
268 | goto failure; | |
269 | ||
270 | return 0; | |
271 | ||
272 | failure: | |
273 | /* This unhashes the socket and releases the local port, if necessary. */ | |
274 | tcp_set_state(sk, TCP_CLOSE); | |
275 | ip_rt_put(rt); | |
276 | sk->sk_route_caps = 0; | |
277 | inet->dport = 0; | |
278 | return err; | |
279 | } | |
280 | ||
1da177e4 LT |
281 | /* |
282 | * This routine does path mtu discovery as defined in RFC1191. | |
283 | */ | |
40efc6fa | 284 | static void do_pmtu_discovery(struct sock *sk, struct iphdr *iph, u32 mtu) |
1da177e4 LT |
285 | { |
286 | struct dst_entry *dst; | |
287 | struct inet_sock *inet = inet_sk(sk); | |
1da177e4 LT |
288 | |
289 | /* We are not interested in TCP_LISTEN and open_requests (SYN-ACKs | |
290 | * send out by Linux are always <576bytes so they should go through | |
291 | * unfragmented). | |
292 | */ | |
293 | if (sk->sk_state == TCP_LISTEN) | |
294 | return; | |
295 | ||
296 | /* We don't check in the destentry if pmtu discovery is forbidden | |
297 | * on this route. We just assume that no packet_to_big packets | |
298 | * are send back when pmtu discovery is not active. | |
299 | * There is a small race when the user changes this flag in the | |
300 | * route, but I think that's acceptable. | |
301 | */ | |
302 | if ((dst = __sk_dst_check(sk, 0)) == NULL) | |
303 | return; | |
304 | ||
305 | dst->ops->update_pmtu(dst, mtu); | |
306 | ||
307 | /* Something is about to be wrong... Remember soft error | |
308 | * for the case, if this connection will not able to recover. | |
309 | */ | |
310 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
311 | sk->sk_err_soft = EMSGSIZE; | |
312 | ||
313 | mtu = dst_mtu(dst); | |
314 | ||
315 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
d83d8461 | 316 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
1da177e4 LT |
317 | tcp_sync_mss(sk, mtu); |
318 | ||
319 | /* Resend the TCP packet because it's | |
320 | * clear that the old packet has been | |
321 | * dropped. This is the new "fast" path mtu | |
322 | * discovery. | |
323 | */ | |
324 | tcp_simple_retransmit(sk); | |
325 | } /* else let the usual retransmit timer handle it */ | |
326 | } | |
327 | ||
328 | /* | |
329 | * This routine is called by the ICMP module when it gets some | |
330 | * sort of error condition. If err < 0 then the socket should | |
331 | * be closed and the error returned to the user. If err > 0 | |
332 | * it's just the icmp type << 8 | icmp code. After adjustment | |
333 | * header points to the first 8 bytes of the tcp header. We need | |
334 | * to find the appropriate port. | |
335 | * | |
336 | * The locking strategy used here is very "optimistic". When | |
337 | * someone else accesses the socket the ICMP is just dropped | |
338 | * and for some paths there is no check at all. | |
339 | * A more general error queue to queue errors for later handling | |
340 | * is probably better. | |
341 | * | |
342 | */ | |
343 | ||
344 | void tcp_v4_err(struct sk_buff *skb, u32 info) | |
345 | { | |
346 | struct iphdr *iph = (struct iphdr *)skb->data; | |
347 | struct tcphdr *th = (struct tcphdr *)(skb->data + (iph->ihl << 2)); | |
348 | struct tcp_sock *tp; | |
349 | struct inet_sock *inet; | |
350 | int type = skb->h.icmph->type; | |
351 | int code = skb->h.icmph->code; | |
352 | struct sock *sk; | |
353 | __u32 seq; | |
354 | int err; | |
355 | ||
356 | if (skb->len < (iph->ihl << 2) + 8) { | |
357 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); | |
358 | return; | |
359 | } | |
360 | ||
e48c414e | 361 | sk = inet_lookup(&tcp_hashinfo, iph->daddr, th->dest, iph->saddr, |
463c84b9 | 362 | th->source, inet_iif(skb)); |
1da177e4 LT |
363 | if (!sk) { |
364 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); | |
365 | return; | |
366 | } | |
367 | if (sk->sk_state == TCP_TIME_WAIT) { | |
9469c7b4 | 368 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
369 | return; |
370 | } | |
371 | ||
372 | bh_lock_sock(sk); | |
373 | /* If too many ICMPs get dropped on busy | |
374 | * servers this needs to be solved differently. | |
375 | */ | |
376 | if (sock_owned_by_user(sk)) | |
377 | NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); | |
378 | ||
379 | if (sk->sk_state == TCP_CLOSE) | |
380 | goto out; | |
381 | ||
382 | tp = tcp_sk(sk); | |
383 | seq = ntohl(th->seq); | |
384 | if (sk->sk_state != TCP_LISTEN && | |
385 | !between(seq, tp->snd_una, tp->snd_nxt)) { | |
06ca719f | 386 | NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
387 | goto out; |
388 | } | |
389 | ||
390 | switch (type) { | |
391 | case ICMP_SOURCE_QUENCH: | |
392 | /* Just silently ignore these. */ | |
393 | goto out; | |
394 | case ICMP_PARAMETERPROB: | |
395 | err = EPROTO; | |
396 | break; | |
397 | case ICMP_DEST_UNREACH: | |
398 | if (code > NR_ICMP_UNREACH) | |
399 | goto out; | |
400 | ||
401 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
402 | if (!sock_owned_by_user(sk)) | |
403 | do_pmtu_discovery(sk, iph, info); | |
404 | goto out; | |
405 | } | |
406 | ||
407 | err = icmp_err_convert[code].errno; | |
408 | break; | |
409 | case ICMP_TIME_EXCEEDED: | |
410 | err = EHOSTUNREACH; | |
411 | break; | |
412 | default: | |
413 | goto out; | |
414 | } | |
415 | ||
416 | switch (sk->sk_state) { | |
60236fdd | 417 | struct request_sock *req, **prev; |
1da177e4 LT |
418 | case TCP_LISTEN: |
419 | if (sock_owned_by_user(sk)) | |
420 | goto out; | |
421 | ||
463c84b9 ACM |
422 | req = inet_csk_search_req(sk, &prev, th->dest, |
423 | iph->daddr, iph->saddr); | |
1da177e4 LT |
424 | if (!req) |
425 | goto out; | |
426 | ||
427 | /* ICMPs are not backlogged, hence we cannot get | |
428 | an established socket here. | |
429 | */ | |
430 | BUG_TRAP(!req->sk); | |
431 | ||
2e6599cb | 432 | if (seq != tcp_rsk(req)->snt_isn) { |
1da177e4 LT |
433 | NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); |
434 | goto out; | |
435 | } | |
436 | ||
437 | /* | |
438 | * Still in SYN_RECV, just remove it silently. | |
439 | * There is no good way to pass the error to the newly | |
440 | * created socket, and POSIX does not want network | |
441 | * errors returned from accept(). | |
442 | */ | |
463c84b9 | 443 | inet_csk_reqsk_queue_drop(sk, req, prev); |
1da177e4 LT |
444 | goto out; |
445 | ||
446 | case TCP_SYN_SENT: | |
447 | case TCP_SYN_RECV: /* Cannot happen. | |
448 | It can f.e. if SYNs crossed. | |
449 | */ | |
450 | if (!sock_owned_by_user(sk)) { | |
1da177e4 LT |
451 | sk->sk_err = err; |
452 | ||
453 | sk->sk_error_report(sk); | |
454 | ||
455 | tcp_done(sk); | |
456 | } else { | |
457 | sk->sk_err_soft = err; | |
458 | } | |
459 | goto out; | |
460 | } | |
461 | ||
462 | /* If we've already connected we will keep trying | |
463 | * until we time out, or the user gives up. | |
464 | * | |
465 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
466 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
467 | * but it is obsoleted by pmtu discovery). | |
468 | * | |
469 | * Note, that in modern internet, where routing is unreliable | |
470 | * and in each dark corner broken firewalls sit, sending random | |
471 | * errors ordered by their masters even this two messages finally lose | |
472 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
473 | * | |
474 | * Now we are in compliance with RFCs. | |
475 | * --ANK (980905) | |
476 | */ | |
477 | ||
478 | inet = inet_sk(sk); | |
479 | if (!sock_owned_by_user(sk) && inet->recverr) { | |
480 | sk->sk_err = err; | |
481 | sk->sk_error_report(sk); | |
482 | } else { /* Only an error on timeout */ | |
483 | sk->sk_err_soft = err; | |
484 | } | |
485 | ||
486 | out: | |
487 | bh_unlock_sock(sk); | |
488 | sock_put(sk); | |
489 | } | |
490 | ||
491 | /* This routine computes an IPv4 TCP checksum. */ | |
8292a17a | 492 | void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb) |
1da177e4 LT |
493 | { |
494 | struct inet_sock *inet = inet_sk(sk); | |
8292a17a | 495 | struct tcphdr *th = skb->h.th; |
1da177e4 | 496 | |
84fa7933 | 497 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
1da177e4 LT |
498 | th->check = ~tcp_v4_check(th, len, inet->saddr, inet->daddr, 0); |
499 | skb->csum = offsetof(struct tcphdr, check); | |
500 | } else { | |
501 | th->check = tcp_v4_check(th, len, inet->saddr, inet->daddr, | |
502 | csum_partial((char *)th, | |
503 | th->doff << 2, | |
504 | skb->csum)); | |
505 | } | |
506 | } | |
507 | ||
a430a43d HX |
508 | int tcp_v4_gso_send_check(struct sk_buff *skb) |
509 | { | |
510 | struct iphdr *iph; | |
511 | struct tcphdr *th; | |
512 | ||
513 | if (!pskb_may_pull(skb, sizeof(*th))) | |
514 | return -EINVAL; | |
515 | ||
516 | iph = skb->nh.iph; | |
517 | th = skb->h.th; | |
518 | ||
519 | th->check = 0; | |
520 | th->check = ~tcp_v4_check(th, skb->len, iph->saddr, iph->daddr, 0); | |
521 | skb->csum = offsetof(struct tcphdr, check); | |
84fa7933 | 522 | skb->ip_summed = CHECKSUM_PARTIAL; |
a430a43d HX |
523 | return 0; |
524 | } | |
525 | ||
1da177e4 LT |
526 | /* |
527 | * This routine will send an RST to the other tcp. | |
528 | * | |
529 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) | |
530 | * for reset. | |
531 | * Answer: if a packet caused RST, it is not for a socket | |
532 | * existing in our system, if it is matched to a socket, | |
533 | * it is just duplicate segment or bug in other side's TCP. | |
534 | * So that we build reply only basing on parameters | |
535 | * arrived with segment. | |
536 | * Exception: precedence violation. We do not implement it in any case. | |
537 | */ | |
538 | ||
cfb6eeb4 | 539 | static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) |
1da177e4 LT |
540 | { |
541 | struct tcphdr *th = skb->h.th; | |
cfb6eeb4 YH |
542 | struct { |
543 | struct tcphdr th; | |
544 | #ifdef CONFIG_TCP_MD5SIG | |
714e85be | 545 | __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)]; |
cfb6eeb4 YH |
546 | #endif |
547 | } rep; | |
1da177e4 | 548 | struct ip_reply_arg arg; |
cfb6eeb4 YH |
549 | #ifdef CONFIG_TCP_MD5SIG |
550 | struct tcp_md5sig_key *key; | |
551 | #endif | |
1da177e4 LT |
552 | |
553 | /* Never send a reset in response to a reset. */ | |
554 | if (th->rst) | |
555 | return; | |
556 | ||
557 | if (((struct rtable *)skb->dst)->rt_type != RTN_LOCAL) | |
558 | return; | |
559 | ||
560 | /* Swap the send and the receive. */ | |
cfb6eeb4 YH |
561 | memset(&rep, 0, sizeof(rep)); |
562 | rep.th.dest = th->source; | |
563 | rep.th.source = th->dest; | |
564 | rep.th.doff = sizeof(struct tcphdr) / 4; | |
565 | rep.th.rst = 1; | |
1da177e4 LT |
566 | |
567 | if (th->ack) { | |
cfb6eeb4 | 568 | rep.th.seq = th->ack_seq; |
1da177e4 | 569 | } else { |
cfb6eeb4 YH |
570 | rep.th.ack = 1; |
571 | rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + | |
572 | skb->len - (th->doff << 2)); | |
1da177e4 LT |
573 | } |
574 | ||
575 | memset(&arg, 0, sizeof arg); | |
cfb6eeb4 YH |
576 | arg.iov[0].iov_base = (unsigned char *)&rep; |
577 | arg.iov[0].iov_len = sizeof(rep.th); | |
578 | ||
579 | #ifdef CONFIG_TCP_MD5SIG | |
580 | key = sk ? tcp_v4_md5_do_lookup(sk, skb->nh.iph->daddr) : NULL; | |
581 | if (key) { | |
582 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | | |
583 | (TCPOPT_NOP << 16) | | |
584 | (TCPOPT_MD5SIG << 8) | | |
585 | TCPOLEN_MD5SIG); | |
586 | /* Update length and the length the header thinks exists */ | |
587 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
588 | rep.th.doff = arg.iov[0].iov_len / 4; | |
589 | ||
590 | tcp_v4_do_calc_md5_hash((__u8 *)&rep.opt[1], | |
591 | key, | |
592 | skb->nh.iph->daddr, | |
593 | skb->nh.iph->saddr, | |
594 | &rep.th, IPPROTO_TCP, | |
595 | arg.iov[0].iov_len); | |
596 | } | |
597 | #endif | |
598 | ||
1da177e4 LT |
599 | arg.csum = csum_tcpudp_nofold(skb->nh.iph->daddr, |
600 | skb->nh.iph->saddr, /*XXX*/ | |
601 | sizeof(struct tcphdr), IPPROTO_TCP, 0); | |
602 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
603 | ||
cfb6eeb4 | 604 | ip_send_reply(tcp_socket->sk, skb, &arg, arg.iov[0].iov_len); |
1da177e4 LT |
605 | |
606 | TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); | |
607 | TCP_INC_STATS_BH(TCP_MIB_OUTRSTS); | |
608 | } | |
609 | ||
610 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states | |
611 | outside socket context is ugly, certainly. What can I do? | |
612 | */ | |
613 | ||
cfb6eeb4 YH |
614 | static void tcp_v4_send_ack(struct tcp_timewait_sock *twsk, |
615 | struct sk_buff *skb, u32 seq, u32 ack, | |
1da177e4 LT |
616 | u32 win, u32 ts) |
617 | { | |
618 | struct tcphdr *th = skb->h.th; | |
619 | struct { | |
620 | struct tcphdr th; | |
714e85be | 621 | __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) |
cfb6eeb4 | 622 | #ifdef CONFIG_TCP_MD5SIG |
714e85be | 623 | + (TCPOLEN_MD5SIG_ALIGNED >> 2) |
cfb6eeb4 YH |
624 | #endif |
625 | ]; | |
1da177e4 LT |
626 | } rep; |
627 | struct ip_reply_arg arg; | |
cfb6eeb4 YH |
628 | #ifdef CONFIG_TCP_MD5SIG |
629 | struct tcp_md5sig_key *key; | |
630 | struct tcp_md5sig_key tw_key; | |
631 | #endif | |
1da177e4 LT |
632 | |
633 | memset(&rep.th, 0, sizeof(struct tcphdr)); | |
634 | memset(&arg, 0, sizeof arg); | |
635 | ||
636 | arg.iov[0].iov_base = (unsigned char *)&rep; | |
637 | arg.iov[0].iov_len = sizeof(rep.th); | |
638 | if (ts) { | |
cfb6eeb4 YH |
639 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
640 | (TCPOPT_TIMESTAMP << 8) | | |
641 | TCPOLEN_TIMESTAMP); | |
642 | rep.opt[1] = htonl(tcp_time_stamp); | |
643 | rep.opt[2] = htonl(ts); | |
644 | arg.iov[0].iov_len = TCPOLEN_TSTAMP_ALIGNED; | |
1da177e4 LT |
645 | } |
646 | ||
647 | /* Swap the send and the receive. */ | |
648 | rep.th.dest = th->source; | |
649 | rep.th.source = th->dest; | |
650 | rep.th.doff = arg.iov[0].iov_len / 4; | |
651 | rep.th.seq = htonl(seq); | |
652 | rep.th.ack_seq = htonl(ack); | |
653 | rep.th.ack = 1; | |
654 | rep.th.window = htons(win); | |
655 | ||
cfb6eeb4 YH |
656 | #ifdef CONFIG_TCP_MD5SIG |
657 | /* | |
658 | * The SKB holds an imcoming packet, but may not have a valid ->sk | |
659 | * pointer. This is especially the case when we're dealing with a | |
660 | * TIME_WAIT ack, because the sk structure is long gone, and only | |
661 | * the tcp_timewait_sock remains. So the md5 key is stashed in that | |
662 | * structure, and we use it in preference. I believe that (twsk || | |
663 | * skb->sk) holds true, but we program defensively. | |
664 | */ | |
665 | if (!twsk && skb->sk) { | |
666 | key = tcp_v4_md5_do_lookup(skb->sk, skb->nh.iph->daddr); | |
667 | } else if (twsk && twsk->tw_md5_keylen) { | |
668 | tw_key.key = twsk->tw_md5_key; | |
669 | tw_key.keylen = twsk->tw_md5_keylen; | |
670 | key = &tw_key; | |
671 | } else { | |
672 | key = NULL; | |
673 | } | |
674 | ||
675 | if (key) { | |
676 | int offset = (ts) ? 3 : 0; | |
677 | ||
678 | rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | | |
679 | (TCPOPT_NOP << 16) | | |
680 | (TCPOPT_MD5SIG << 8) | | |
681 | TCPOLEN_MD5SIG); | |
682 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
683 | rep.th.doff = arg.iov[0].iov_len/4; | |
684 | ||
685 | tcp_v4_do_calc_md5_hash((__u8 *)&rep.opt[offset], | |
686 | key, | |
687 | skb->nh.iph->daddr, | |
688 | skb->nh.iph->saddr, | |
689 | &rep.th, IPPROTO_TCP, | |
690 | arg.iov[0].iov_len); | |
691 | } | |
692 | #endif | |
693 | ||
1da177e4 LT |
694 | arg.csum = csum_tcpudp_nofold(skb->nh.iph->daddr, |
695 | skb->nh.iph->saddr, /*XXX*/ | |
696 | arg.iov[0].iov_len, IPPROTO_TCP, 0); | |
697 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
698 | ||
699 | ip_send_reply(tcp_socket->sk, skb, &arg, arg.iov[0].iov_len); | |
700 | ||
701 | TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); | |
702 | } | |
703 | ||
704 | static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) | |
705 | { | |
8feaf0c0 | 706 | struct inet_timewait_sock *tw = inet_twsk(sk); |
cfb6eeb4 | 707 | struct tcp_timewait_sock *tcptw = tcp_twsk(sk); |
1da177e4 | 708 | |
cfb6eeb4 | 709 | tcp_v4_send_ack(tcptw, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
8feaf0c0 | 710 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, tcptw->tw_ts_recent); |
1da177e4 | 711 | |
8feaf0c0 | 712 | inet_twsk_put(tw); |
1da177e4 LT |
713 | } |
714 | ||
60236fdd | 715 | static void tcp_v4_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req) |
1da177e4 | 716 | { |
cfb6eeb4 YH |
717 | tcp_v4_send_ack(NULL, skb, tcp_rsk(req)->snt_isn + 1, |
718 | tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, | |
1da177e4 LT |
719 | req->ts_recent); |
720 | } | |
721 | ||
1da177e4 LT |
722 | /* |
723 | * Send a SYN-ACK after having received an ACK. | |
60236fdd | 724 | * This still operates on a request_sock only, not on a big |
1da177e4 LT |
725 | * socket. |
726 | */ | |
60236fdd | 727 | static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req, |
1da177e4 LT |
728 | struct dst_entry *dst) |
729 | { | |
2e6599cb | 730 | const struct inet_request_sock *ireq = inet_rsk(req); |
1da177e4 LT |
731 | int err = -1; |
732 | struct sk_buff * skb; | |
733 | ||
734 | /* First, grab a route. */ | |
463c84b9 | 735 | if (!dst && (dst = inet_csk_route_req(sk, req)) == NULL) |
1da177e4 LT |
736 | goto out; |
737 | ||
738 | skb = tcp_make_synack(sk, dst, req); | |
739 | ||
740 | if (skb) { | |
741 | struct tcphdr *th = skb->h.th; | |
742 | ||
743 | th->check = tcp_v4_check(th, skb->len, | |
2e6599cb ACM |
744 | ireq->loc_addr, |
745 | ireq->rmt_addr, | |
1da177e4 LT |
746 | csum_partial((char *)th, skb->len, |
747 | skb->csum)); | |
748 | ||
2e6599cb ACM |
749 | err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, |
750 | ireq->rmt_addr, | |
751 | ireq->opt); | |
b9df3cb8 | 752 | err = net_xmit_eval(err); |
1da177e4 LT |
753 | } |
754 | ||
755 | out: | |
756 | dst_release(dst); | |
757 | return err; | |
758 | } | |
759 | ||
760 | /* | |
60236fdd | 761 | * IPv4 request_sock destructor. |
1da177e4 | 762 | */ |
60236fdd | 763 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
1da177e4 | 764 | { |
a51482bd | 765 | kfree(inet_rsk(req)->opt); |
1da177e4 LT |
766 | } |
767 | ||
80e40daa | 768 | #ifdef CONFIG_SYN_COOKIES |
40efc6fa | 769 | static void syn_flood_warning(struct sk_buff *skb) |
1da177e4 LT |
770 | { |
771 | static unsigned long warntime; | |
772 | ||
773 | if (time_after(jiffies, (warntime + HZ * 60))) { | |
774 | warntime = jiffies; | |
775 | printk(KERN_INFO | |
776 | "possible SYN flooding on port %d. Sending cookies.\n", | |
777 | ntohs(skb->h.th->dest)); | |
778 | } | |
779 | } | |
80e40daa | 780 | #endif |
1da177e4 LT |
781 | |
782 | /* | |
60236fdd | 783 | * Save and compile IPv4 options into the request_sock if needed. |
1da177e4 | 784 | */ |
40efc6fa SH |
785 | static struct ip_options *tcp_v4_save_options(struct sock *sk, |
786 | struct sk_buff *skb) | |
1da177e4 LT |
787 | { |
788 | struct ip_options *opt = &(IPCB(skb)->opt); | |
789 | struct ip_options *dopt = NULL; | |
790 | ||
791 | if (opt && opt->optlen) { | |
792 | int opt_size = optlength(opt); | |
793 | dopt = kmalloc(opt_size, GFP_ATOMIC); | |
794 | if (dopt) { | |
795 | if (ip_options_echo(dopt, skb)) { | |
796 | kfree(dopt); | |
797 | dopt = NULL; | |
798 | } | |
799 | } | |
800 | } | |
801 | return dopt; | |
802 | } | |
803 | ||
cfb6eeb4 YH |
804 | #ifdef CONFIG_TCP_MD5SIG |
805 | /* | |
806 | * RFC2385 MD5 checksumming requires a mapping of | |
807 | * IP address->MD5 Key. | |
808 | * We need to maintain these in the sk structure. | |
809 | */ | |
810 | ||
811 | /* Find the Key structure for an address. */ | |
812 | static struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, __be32 addr) | |
813 | { | |
814 | struct tcp_sock *tp = tcp_sk(sk); | |
815 | int i; | |
816 | ||
817 | if (!tp->md5sig_info || !tp->md5sig_info->entries4) | |
818 | return NULL; | |
819 | for (i = 0; i < tp->md5sig_info->entries4; i++) { | |
820 | if (tp->md5sig_info->keys4[i].addr == addr) | |
821 | return (struct tcp_md5sig_key *)&tp->md5sig_info->keys4[i]; | |
822 | } | |
823 | return NULL; | |
824 | } | |
825 | ||
826 | struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk, | |
827 | struct sock *addr_sk) | |
828 | { | |
829 | return tcp_v4_md5_do_lookup(sk, inet_sk(addr_sk)->daddr); | |
830 | } | |
831 | ||
832 | EXPORT_SYMBOL(tcp_v4_md5_lookup); | |
833 | ||
834 | struct tcp_md5sig_key *tcp_v4_reqsk_md5_lookup(struct sock *sk, | |
835 | struct request_sock *req) | |
836 | { | |
837 | return tcp_v4_md5_do_lookup(sk, inet_rsk(req)->rmt_addr); | |
838 | } | |
839 | ||
840 | /* This can be called on a newly created socket, from other files */ | |
841 | int tcp_v4_md5_do_add(struct sock *sk, __be32 addr, | |
842 | u8 *newkey, u8 newkeylen) | |
843 | { | |
844 | /* Add Key to the list */ | |
845 | struct tcp4_md5sig_key *key; | |
846 | struct tcp_sock *tp = tcp_sk(sk); | |
847 | struct tcp4_md5sig_key *keys; | |
848 | ||
849 | key = (struct tcp4_md5sig_key *) tcp_v4_md5_do_lookup(sk, addr); | |
850 | if (key) { | |
851 | /* Pre-existing entry - just update that one. */ | |
852 | kfree (key->key); | |
853 | key->key = newkey; | |
854 | key->keylen = newkeylen; | |
855 | } else { | |
856 | if (!tp->md5sig_info) { | |
857 | tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC); | |
858 | if (!tp->md5sig_info) { | |
859 | kfree(newkey); | |
860 | return -ENOMEM; | |
861 | } | |
862 | } | |
863 | if (tcp_alloc_md5sig_pool() == NULL) { | |
864 | kfree(newkey); | |
865 | return -ENOMEM; | |
866 | } | |
867 | if (tp->md5sig_info->alloced4 == tp->md5sig_info->entries4) { | |
868 | keys = kmalloc((sizeof(struct tcp4_md5sig_key) * | |
869 | (tp->md5sig_info->entries4 + 1)), GFP_ATOMIC); | |
870 | if (!keys) { | |
871 | kfree(newkey); | |
872 | tcp_free_md5sig_pool(); | |
873 | return -ENOMEM; | |
874 | } | |
875 | ||
876 | if (tp->md5sig_info->entries4) | |
877 | memcpy(keys, tp->md5sig_info->keys4, | |
878 | (sizeof (struct tcp4_md5sig_key) * | |
879 | tp->md5sig_info->entries4)); | |
880 | ||
881 | /* Free old key list, and reference new one */ | |
882 | if (tp->md5sig_info->keys4) | |
883 | kfree(tp->md5sig_info->keys4); | |
884 | tp->md5sig_info->keys4 = keys; | |
885 | tp->md5sig_info->alloced4++; | |
886 | } | |
887 | tp->md5sig_info->entries4++; | |
888 | tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].addr = addr; | |
889 | tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].key = newkey; | |
890 | tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].keylen = newkeylen; | |
891 | } | |
892 | return 0; | |
893 | } | |
894 | ||
895 | EXPORT_SYMBOL(tcp_v4_md5_do_add); | |
896 | ||
897 | static int tcp_v4_md5_add_func(struct sock *sk, struct sock *addr_sk, | |
898 | u8 *newkey, u8 newkeylen) | |
899 | { | |
900 | return tcp_v4_md5_do_add(sk, inet_sk(addr_sk)->daddr, | |
901 | newkey, newkeylen); | |
902 | } | |
903 | ||
904 | int tcp_v4_md5_do_del(struct sock *sk, __be32 addr) | |
905 | { | |
906 | struct tcp_sock *tp = tcp_sk(sk); | |
907 | int i; | |
908 | ||
909 | for (i = 0; i < tp->md5sig_info->entries4; i++) { | |
910 | if (tp->md5sig_info->keys4[i].addr == addr) { | |
911 | /* Free the key */ | |
912 | kfree(tp->md5sig_info->keys4[i].key); | |
913 | tp->md5sig_info->entries4--; | |
914 | ||
915 | if (tp->md5sig_info->entries4 == 0) { | |
916 | kfree(tp->md5sig_info->keys4); | |
917 | tp->md5sig_info->keys4 = NULL; | |
918 | } else { | |
919 | /* Need to do some manipulation */ | |
920 | if (tp->md5sig_info->entries4 != i) | |
921 | memcpy(&tp->md5sig_info->keys4[i], | |
922 | &tp->md5sig_info->keys4[i+1], | |
923 | (tp->md5sig_info->entries4 - i) | |
924 | * sizeof (struct tcp4_md5sig_key)); | |
925 | } | |
926 | tcp_free_md5sig_pool(); | |
927 | return 0; | |
928 | } | |
929 | } | |
930 | return -ENOENT; | |
931 | } | |
932 | ||
933 | EXPORT_SYMBOL(tcp_v4_md5_do_del); | |
934 | ||
935 | static void tcp_v4_clear_md5_list (struct sock *sk) | |
936 | { | |
937 | struct tcp_sock *tp = tcp_sk(sk); | |
938 | ||
939 | /* Free each key, then the set of key keys, | |
940 | * the crypto element, and then decrement our | |
941 | * hold on the last resort crypto. | |
942 | */ | |
943 | if (tp->md5sig_info->entries4) { | |
944 | int i; | |
945 | for (i = 0; i < tp->md5sig_info->entries4; i++) | |
946 | kfree(tp->md5sig_info->keys4[i].key); | |
947 | tp->md5sig_info->entries4 = 0; | |
948 | tcp_free_md5sig_pool(); | |
949 | } | |
950 | if (tp->md5sig_info->keys4) { | |
951 | kfree(tp->md5sig_info->keys4); | |
952 | tp->md5sig_info->keys4 = NULL; | |
953 | tp->md5sig_info->alloced4 = 0; | |
954 | } | |
955 | } | |
956 | ||
957 | static int tcp_v4_parse_md5_keys (struct sock *sk, char __user *optval, | |
958 | int optlen) | |
959 | { | |
960 | struct tcp_md5sig cmd; | |
961 | struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; | |
962 | u8 *newkey; | |
963 | ||
964 | if (optlen < sizeof(cmd)) | |
965 | return -EINVAL; | |
966 | ||
967 | if (copy_from_user (&cmd, optval, sizeof(cmd))) | |
968 | return -EFAULT; | |
969 | ||
970 | if (sin->sin_family != AF_INET) | |
971 | return -EINVAL; | |
972 | ||
973 | if (!cmd.tcpm_key || !cmd.tcpm_keylen) { | |
974 | if (!tcp_sk(sk)->md5sig_info) | |
975 | return -ENOENT; | |
976 | return tcp_v4_md5_do_del(sk, sin->sin_addr.s_addr); | |
977 | } | |
978 | ||
979 | if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) | |
980 | return -EINVAL; | |
981 | ||
982 | if (!tcp_sk(sk)->md5sig_info) { | |
983 | struct tcp_sock *tp = tcp_sk(sk); | |
984 | struct tcp_md5sig_info *p; | |
985 | ||
986 | p = kzalloc(sizeof(struct tcp_md5sig_info), GFP_KERNEL); | |
987 | if (!p) | |
988 | return -EINVAL; | |
989 | ||
990 | tp->md5sig_info = p; | |
991 | ||
992 | } | |
993 | ||
994 | newkey = kmalloc(cmd.tcpm_keylen, GFP_KERNEL); | |
995 | if (!newkey) | |
996 | return -ENOMEM; | |
997 | memcpy(newkey, cmd.tcpm_key, cmd.tcpm_keylen); | |
998 | return tcp_v4_md5_do_add(sk, sin->sin_addr.s_addr, | |
999 | newkey, cmd.tcpm_keylen); | |
1000 | } | |
1001 | ||
1002 | static int tcp_v4_do_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key, | |
1003 | __be32 saddr, __be32 daddr, | |
1004 | struct tcphdr *th, int protocol, | |
1005 | int tcplen) | |
1006 | { | |
1007 | struct scatterlist sg[4]; | |
1008 | __u16 data_len; | |
1009 | int block = 0; | |
1010 | #ifdef CONFIG_TCP_MD5SIG_DEBUG | |
1011 | int i; | |
1012 | #endif | |
1013 | __u16 old_checksum; | |
1014 | struct tcp_md5sig_pool *hp; | |
1015 | struct tcp4_pseudohdr *bp; | |
1016 | struct hash_desc *desc; | |
1017 | int err; | |
1018 | unsigned int nbytes = 0; | |
1019 | ||
1020 | /* | |
1021 | * Okay, so RFC2385 is turned on for this connection, | |
1022 | * so we need to generate the MD5 hash for the packet now. | |
1023 | */ | |
1024 | ||
1025 | hp = tcp_get_md5sig_pool(); | |
1026 | if (!hp) | |
1027 | goto clear_hash_noput; | |
1028 | ||
1029 | bp = &hp->md5_blk.ip4; | |
1030 | desc = &hp->md5_desc; | |
1031 | ||
1032 | /* | |
1033 | * 1. the TCP pseudo-header (in the order: source IP address, | |
1034 | * destination IP address, zero-padded protocol number, and | |
1035 | * segment length) | |
1036 | */ | |
1037 | bp->saddr = saddr; | |
1038 | bp->daddr = daddr; | |
1039 | bp->pad = 0; | |
1040 | bp->protocol = protocol; | |
1041 | bp->len = htons(tcplen); | |
1042 | sg_set_buf(&sg[block++], bp, sizeof(*bp)); | |
1043 | nbytes += sizeof(*bp); | |
1044 | ||
1045 | #ifdef CONFIG_TCP_MD5SIG_DEBUG | |
1046 | printk("Calcuating hash for: "); | |
1047 | for (i = 0; i < sizeof (*bp); i++) | |
1048 | printk ("%02x ", (unsigned int)((unsigned char *)bp)[i]); | |
1049 | printk(" "); | |
1050 | #endif | |
1051 | ||
1052 | /* 2. the TCP header, excluding options, and assuming a | |
1053 | * checksum of zero/ | |
1054 | */ | |
1055 | old_checksum = th->check; | |
1056 | th->check = 0; | |
1057 | sg_set_buf(&sg[block++], th, sizeof(struct tcphdr)); | |
1058 | nbytes += sizeof(struct tcphdr); | |
1059 | #ifdef CONFIG_TCP_MD5SIG_DEBUG | |
1060 | for (i = 0; i < sizeof (struct tcphdr); i++) | |
1061 | printk (" %02x", (unsigned int)((unsigned char *)th)[i]); | |
1062 | #endif | |
1063 | /* 3. the TCP segment data (if any) */ | |
1064 | data_len = tcplen - (th->doff << 2); | |
1065 | if (data_len > 0) { | |
1066 | unsigned char *data = (unsigned char *)th + (th->doff << 2); | |
1067 | sg_set_buf(&sg[block++], data, data_len); | |
1068 | nbytes += data_len; | |
1069 | } | |
1070 | ||
1071 | /* 4. an independently-specified key or password, known to both | |
1072 | * TCPs and presumably connection-specific | |
1073 | */ | |
1074 | sg_set_buf(&sg[block++], key->key, key->keylen); | |
1075 | nbytes += key->keylen; | |
1076 | ||
1077 | #ifdef CONFIG_TCP_MD5SIG_DEBUG | |
1078 | printk (" and password: "); | |
1079 | for (i = 0; i < key->keylen; i++) | |
1080 | printk ("%02x ", (unsigned int)key->key[i]); | |
1081 | #endif | |
1082 | ||
1083 | /* Now store the Hash into the packet */ | |
1084 | err = crypto_hash_init(desc); | |
1085 | if (err) | |
1086 | goto clear_hash; | |
1087 | err = crypto_hash_update(desc, sg, nbytes); | |
1088 | if (err) | |
1089 | goto clear_hash; | |
1090 | err = crypto_hash_final(desc, md5_hash); | |
1091 | if (err) | |
1092 | goto clear_hash; | |
1093 | ||
1094 | /* Reset header, and free up the crypto */ | |
1095 | tcp_put_md5sig_pool(); | |
1096 | th->check = old_checksum; | |
1097 | ||
1098 | out: | |
1099 | #ifdef CONFIG_TCP_MD5SIG_DEBUG | |
1100 | printk(" result:"); | |
1101 | for (i = 0; i < 16; i++) | |
1102 | printk (" %02x", (unsigned int)(((u8*)md5_hash)[i])); | |
1103 | printk("\n"); | |
1104 | #endif | |
1105 | return 0; | |
1106 | clear_hash: | |
1107 | tcp_put_md5sig_pool(); | |
1108 | clear_hash_noput: | |
1109 | memset(md5_hash, 0, 16); | |
1110 | goto out; | |
1111 | } | |
1112 | ||
1113 | int tcp_v4_calc_md5_hash(char *md5_hash, struct tcp_md5sig_key *key, | |
1114 | struct sock *sk, | |
1115 | struct dst_entry *dst, | |
1116 | struct request_sock *req, | |
1117 | struct tcphdr *th, int protocol, | |
1118 | int tcplen) | |
1119 | { | |
1120 | __be32 saddr, daddr; | |
1121 | ||
1122 | if (sk) { | |
1123 | saddr = inet_sk(sk)->saddr; | |
1124 | daddr = inet_sk(sk)->daddr; | |
1125 | } else { | |
1126 | struct rtable *rt = (struct rtable *)dst; | |
1127 | BUG_ON(!rt); | |
1128 | saddr = rt->rt_src; | |
1129 | daddr = rt->rt_dst; | |
1130 | } | |
1131 | return tcp_v4_do_calc_md5_hash(md5_hash, key, | |
1132 | saddr, daddr, | |
1133 | th, protocol, tcplen); | |
1134 | } | |
1135 | ||
1136 | EXPORT_SYMBOL(tcp_v4_calc_md5_hash); | |
1137 | ||
1138 | static int tcp_v4_inbound_md5_hash (struct sock *sk, struct sk_buff *skb) | |
1139 | { | |
1140 | /* | |
1141 | * This gets called for each TCP segment that arrives | |
1142 | * so we want to be efficient. | |
1143 | * We have 3 drop cases: | |
1144 | * o No MD5 hash and one expected. | |
1145 | * o MD5 hash and we're not expecting one. | |
1146 | * o MD5 hash and its wrong. | |
1147 | */ | |
1148 | __u8 *hash_location = NULL; | |
1149 | struct tcp_md5sig_key *hash_expected; | |
1150 | struct iphdr *iph = skb->nh.iph; | |
1151 | struct tcphdr *th = skb->h.th; | |
1152 | int length = (th->doff << 2) - sizeof (struct tcphdr); | |
1153 | int genhash; | |
1154 | unsigned char *ptr; | |
1155 | unsigned char newhash[16]; | |
1156 | ||
1157 | hash_expected = tcp_v4_md5_do_lookup(sk, iph->saddr); | |
1158 | ||
1159 | /* | |
1160 | * If the TCP option length is less than the TCP_MD5SIG | |
1161 | * option length, then we can shortcut | |
1162 | */ | |
1163 | if (length < TCPOLEN_MD5SIG) { | |
1164 | if (hash_expected) | |
1165 | return 1; | |
1166 | else | |
1167 | return 0; | |
1168 | } | |
1169 | ||
1170 | /* Okay, we can't shortcut - we have to grub through the options */ | |
1171 | ptr = (unsigned char *)(th + 1); | |
1172 | while (length > 0) { | |
1173 | int opcode = *ptr++; | |
1174 | int opsize; | |
1175 | ||
1176 | switch (opcode) { | |
1177 | case TCPOPT_EOL: | |
1178 | goto done_opts; | |
1179 | case TCPOPT_NOP: | |
1180 | length--; | |
1181 | continue; | |
1182 | default: | |
1183 | opsize = *ptr++; | |
1184 | if (opsize < 2) | |
1185 | goto done_opts; | |
1186 | if (opsize > length) | |
1187 | goto done_opts; | |
1188 | ||
1189 | if (opcode == TCPOPT_MD5SIG) { | |
1190 | hash_location = ptr; | |
1191 | goto done_opts; | |
1192 | } | |
1193 | } | |
1194 | ptr += opsize-2; | |
1195 | length -= opsize; | |
1196 | } | |
1197 | done_opts: | |
1198 | /* We've parsed the options - do we have a hash? */ | |
1199 | if (!hash_expected && !hash_location) | |
1200 | return 0; | |
1201 | ||
1202 | if (hash_expected && !hash_location) { | |
1203 | if (net_ratelimit()) { | |
1204 | printk(KERN_INFO "MD5 Hash NOT expected but found " | |
1205 | "(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)\n", | |
1206 | NIPQUAD (iph->saddr), ntohs(th->source), | |
1207 | NIPQUAD (iph->daddr), ntohs(th->dest)); | |
1208 | } | |
1209 | return 1; | |
1210 | } | |
1211 | ||
1212 | if (!hash_expected && hash_location) { | |
1213 | if (net_ratelimit()) { | |
1214 | printk(KERN_INFO "MD5 Hash NOT expected but found " | |
1215 | "(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)\n", | |
1216 | NIPQUAD (iph->saddr), ntohs(th->source), | |
1217 | NIPQUAD (iph->daddr), ntohs(th->dest)); | |
1218 | } | |
1219 | return 1; | |
1220 | } | |
1221 | ||
1222 | /* Okay, so this is hash_expected and hash_location - | |
1223 | * so we need to calculate the checksum. | |
1224 | */ | |
1225 | genhash = tcp_v4_do_calc_md5_hash(newhash, | |
1226 | hash_expected, | |
1227 | iph->saddr, iph->daddr, | |
1228 | th, sk->sk_protocol, | |
1229 | skb->len); | |
1230 | ||
1231 | if (genhash || memcmp(hash_location, newhash, 16) != 0) { | |
1232 | if (net_ratelimit()) { | |
1233 | printk(KERN_INFO "MD5 Hash failed for " | |
1234 | "(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)%s\n", | |
1235 | NIPQUAD (iph->saddr), ntohs(th->source), | |
1236 | NIPQUAD (iph->daddr), ntohs(th->dest), | |
1237 | genhash ? " tcp_v4_calc_md5_hash failed" : ""); | |
1238 | #ifdef CONFIG_TCP_MD5SIG_DEBUG | |
1239 | do { | |
1240 | int i; | |
1241 | printk("Received: "); | |
1242 | for (i = 0; i < 16; i++) | |
1243 | printk("%02x ", 0xff & (int)hash_location[i]); | |
1244 | printk("\n"); | |
1245 | printk("Calculated: "); | |
1246 | for (i = 0; i < 16; i++) | |
1247 | printk("%02x ", 0xff & (int)newhash[i]); | |
1248 | printk("\n"); | |
1249 | } while(0); | |
1250 | #endif | |
1251 | } | |
1252 | return 1; | |
1253 | } | |
1254 | return 0; | |
1255 | } | |
1256 | ||
1257 | #endif | |
1258 | ||
72a3effa | 1259 | struct request_sock_ops tcp_request_sock_ops __read_mostly = { |
1da177e4 | 1260 | .family = PF_INET, |
2e6599cb | 1261 | .obj_size = sizeof(struct tcp_request_sock), |
1da177e4 | 1262 | .rtx_syn_ack = tcp_v4_send_synack, |
60236fdd ACM |
1263 | .send_ack = tcp_v4_reqsk_send_ack, |
1264 | .destructor = tcp_v4_reqsk_destructor, | |
1da177e4 LT |
1265 | .send_reset = tcp_v4_send_reset, |
1266 | }; | |
1267 | ||
cfb6eeb4 YH |
1268 | struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { |
1269 | #ifdef CONFIG_TCP_MD5SIG | |
1270 | .md5_lookup = tcp_v4_reqsk_md5_lookup, | |
1271 | #endif | |
1272 | }; | |
1273 | ||
6d6ee43e ACM |
1274 | static struct timewait_sock_ops tcp_timewait_sock_ops = { |
1275 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), | |
1276 | .twsk_unique = tcp_twsk_unique, | |
cfb6eeb4 | 1277 | .twsk_destructor= tcp_twsk_destructor, |
6d6ee43e ACM |
1278 | }; |
1279 | ||
1da177e4 LT |
1280 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
1281 | { | |
2e6599cb | 1282 | struct inet_request_sock *ireq; |
1da177e4 | 1283 | struct tcp_options_received tmp_opt; |
60236fdd | 1284 | struct request_sock *req; |
adaf345b AV |
1285 | __be32 saddr = skb->nh.iph->saddr; |
1286 | __be32 daddr = skb->nh.iph->daddr; | |
1da177e4 LT |
1287 | __u32 isn = TCP_SKB_CB(skb)->when; |
1288 | struct dst_entry *dst = NULL; | |
1289 | #ifdef CONFIG_SYN_COOKIES | |
1290 | int want_cookie = 0; | |
1291 | #else | |
1292 | #define want_cookie 0 /* Argh, why doesn't gcc optimize this :( */ | |
1293 | #endif | |
1294 | ||
1295 | /* Never answer to SYNs send to broadcast or multicast */ | |
1296 | if (((struct rtable *)skb->dst)->rt_flags & | |
1297 | (RTCF_BROADCAST | RTCF_MULTICAST)) | |
1298 | goto drop; | |
1299 | ||
1300 | /* TW buckets are converted to open requests without | |
1301 | * limitations, they conserve resources and peer is | |
1302 | * evidently real one. | |
1303 | */ | |
463c84b9 | 1304 | if (inet_csk_reqsk_queue_is_full(sk) && !isn) { |
1da177e4 LT |
1305 | #ifdef CONFIG_SYN_COOKIES |
1306 | if (sysctl_tcp_syncookies) { | |
1307 | want_cookie = 1; | |
1308 | } else | |
1309 | #endif | |
1310 | goto drop; | |
1311 | } | |
1312 | ||
1313 | /* Accept backlog is full. If we have already queued enough | |
1314 | * of warm entries in syn queue, drop request. It is better than | |
1315 | * clogging syn queue with openreqs with exponentially increasing | |
1316 | * timeout. | |
1317 | */ | |
463c84b9 | 1318 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
1da177e4 LT |
1319 | goto drop; |
1320 | ||
60236fdd | 1321 | req = reqsk_alloc(&tcp_request_sock_ops); |
1da177e4 LT |
1322 | if (!req) |
1323 | goto drop; | |
1324 | ||
cfb6eeb4 YH |
1325 | #ifdef CONFIG_TCP_MD5SIG |
1326 | tcp_rsk(req)->af_specific = &tcp_request_sock_ipv4_ops; | |
1327 | #endif | |
1328 | ||
1da177e4 LT |
1329 | tcp_clear_options(&tmp_opt); |
1330 | tmp_opt.mss_clamp = 536; | |
1331 | tmp_opt.user_mss = tcp_sk(sk)->rx_opt.user_mss; | |
1332 | ||
1333 | tcp_parse_options(skb, &tmp_opt, 0); | |
1334 | ||
1335 | if (want_cookie) { | |
1336 | tcp_clear_options(&tmp_opt); | |
1337 | tmp_opt.saw_tstamp = 0; | |
1338 | } | |
1339 | ||
1340 | if (tmp_opt.saw_tstamp && !tmp_opt.rcv_tsval) { | |
1341 | /* Some OSes (unknown ones, but I see them on web server, which | |
1342 | * contains information interesting only for windows' | |
1343 | * users) do not send their stamp in SYN. It is easy case. | |
1344 | * We simply do not advertise TS support. | |
1345 | */ | |
1346 | tmp_opt.saw_tstamp = 0; | |
1347 | tmp_opt.tstamp_ok = 0; | |
1348 | } | |
1349 | tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; | |
1350 | ||
1351 | tcp_openreq_init(req, &tmp_opt, skb); | |
1352 | ||
4237c75c VY |
1353 | if (security_inet_conn_request(sk, skb, req)) |
1354 | goto drop_and_free; | |
1355 | ||
2e6599cb ACM |
1356 | ireq = inet_rsk(req); |
1357 | ireq->loc_addr = daddr; | |
1358 | ireq->rmt_addr = saddr; | |
1359 | ireq->opt = tcp_v4_save_options(sk, skb); | |
1da177e4 LT |
1360 | if (!want_cookie) |
1361 | TCP_ECN_create_request(req, skb->h.th); | |
1362 | ||
1363 | if (want_cookie) { | |
1364 | #ifdef CONFIG_SYN_COOKIES | |
1365 | syn_flood_warning(skb); | |
1366 | #endif | |
1367 | isn = cookie_v4_init_sequence(sk, skb, &req->mss); | |
1368 | } else if (!isn) { | |
1369 | struct inet_peer *peer = NULL; | |
1370 | ||
1371 | /* VJ's idea. We save last timestamp seen | |
1372 | * from the destination in peer table, when entering | |
1373 | * state TIME-WAIT, and check against it before | |
1374 | * accepting new connection request. | |
1375 | * | |
1376 | * If "isn" is not zero, this request hit alive | |
1377 | * timewait bucket, so that all the necessary checks | |
1378 | * are made in the function processing timewait state. | |
1379 | */ | |
1380 | if (tmp_opt.saw_tstamp && | |
295ff7ed | 1381 | tcp_death_row.sysctl_tw_recycle && |
463c84b9 | 1382 | (dst = inet_csk_route_req(sk, req)) != NULL && |
1da177e4 LT |
1383 | (peer = rt_get_peer((struct rtable *)dst)) != NULL && |
1384 | peer->v4daddr == saddr) { | |
1385 | if (xtime.tv_sec < peer->tcp_ts_stamp + TCP_PAWS_MSL && | |
1386 | (s32)(peer->tcp_ts - req->ts_recent) > | |
1387 | TCP_PAWS_WINDOW) { | |
1388 | NET_INC_STATS_BH(LINUX_MIB_PAWSPASSIVEREJECTED); | |
1389 | dst_release(dst); | |
1390 | goto drop_and_free; | |
1391 | } | |
1392 | } | |
1393 | /* Kill the following clause, if you dislike this way. */ | |
1394 | else if (!sysctl_tcp_syncookies && | |
463c84b9 | 1395 | (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) < |
1da177e4 LT |
1396 | (sysctl_max_syn_backlog >> 2)) && |
1397 | (!peer || !peer->tcp_ts_stamp) && | |
1398 | (!dst || !dst_metric(dst, RTAX_RTT))) { | |
1399 | /* Without syncookies last quarter of | |
1400 | * backlog is filled with destinations, | |
1401 | * proven to be alive. | |
1402 | * It means that we continue to communicate | |
1403 | * to destinations, already remembered | |
1404 | * to the moment of synflood. | |
1405 | */ | |
64ce2073 PM |
1406 | LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open " |
1407 | "request from %u.%u.%u.%u/%u\n", | |
1408 | NIPQUAD(saddr), | |
1409 | ntohs(skb->h.th->source)); | |
1da177e4 LT |
1410 | dst_release(dst); |
1411 | goto drop_and_free; | |
1412 | } | |
1413 | ||
a94f723d | 1414 | isn = tcp_v4_init_sequence(skb); |
1da177e4 | 1415 | } |
2e6599cb | 1416 | tcp_rsk(req)->snt_isn = isn; |
1da177e4 LT |
1417 | |
1418 | if (tcp_v4_send_synack(sk, req, dst)) | |
1419 | goto drop_and_free; | |
1420 | ||
1421 | if (want_cookie) { | |
60236fdd | 1422 | reqsk_free(req); |
1da177e4 | 1423 | } else { |
3f421baa | 1424 | inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); |
1da177e4 LT |
1425 | } |
1426 | return 0; | |
1427 | ||
1428 | drop_and_free: | |
60236fdd | 1429 | reqsk_free(req); |
1da177e4 | 1430 | drop: |
1da177e4 LT |
1431 | return 0; |
1432 | } | |
1433 | ||
1434 | ||
1435 | /* | |
1436 | * The three way handshake has completed - we got a valid synack - | |
1437 | * now create the new socket. | |
1438 | */ | |
1439 | struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, | |
60236fdd | 1440 | struct request_sock *req, |
1da177e4 LT |
1441 | struct dst_entry *dst) |
1442 | { | |
2e6599cb | 1443 | struct inet_request_sock *ireq; |
1da177e4 LT |
1444 | struct inet_sock *newinet; |
1445 | struct tcp_sock *newtp; | |
1446 | struct sock *newsk; | |
cfb6eeb4 YH |
1447 | #ifdef CONFIG_TCP_MD5SIG |
1448 | struct tcp_md5sig_key *key; | |
1449 | #endif | |
1da177e4 LT |
1450 | |
1451 | if (sk_acceptq_is_full(sk)) | |
1452 | goto exit_overflow; | |
1453 | ||
463c84b9 | 1454 | if (!dst && (dst = inet_csk_route_req(sk, req)) == NULL) |
1da177e4 LT |
1455 | goto exit; |
1456 | ||
1457 | newsk = tcp_create_openreq_child(sk, req, skb); | |
1458 | if (!newsk) | |
1459 | goto exit; | |
1460 | ||
bcd76111 | 1461 | newsk->sk_gso_type = SKB_GSO_TCPV4; |
6cbb0df7 | 1462 | sk_setup_caps(newsk, dst); |
1da177e4 LT |
1463 | |
1464 | newtp = tcp_sk(newsk); | |
1465 | newinet = inet_sk(newsk); | |
2e6599cb ACM |
1466 | ireq = inet_rsk(req); |
1467 | newinet->daddr = ireq->rmt_addr; | |
1468 | newinet->rcv_saddr = ireq->loc_addr; | |
1469 | newinet->saddr = ireq->loc_addr; | |
1470 | newinet->opt = ireq->opt; | |
1471 | ireq->opt = NULL; | |
463c84b9 | 1472 | newinet->mc_index = inet_iif(skb); |
1da177e4 | 1473 | newinet->mc_ttl = skb->nh.iph->ttl; |
d83d8461 | 1474 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
1da177e4 | 1475 | if (newinet->opt) |
d83d8461 | 1476 | inet_csk(newsk)->icsk_ext_hdr_len = newinet->opt->optlen; |
1da177e4 LT |
1477 | newinet->id = newtp->write_seq ^ jiffies; |
1478 | ||
5d424d5a | 1479 | tcp_mtup_init(newsk); |
1da177e4 LT |
1480 | tcp_sync_mss(newsk, dst_mtu(dst)); |
1481 | newtp->advmss = dst_metric(dst, RTAX_ADVMSS); | |
1482 | tcp_initialize_rcv_mss(newsk); | |
1483 | ||
cfb6eeb4 YH |
1484 | #ifdef CONFIG_TCP_MD5SIG |
1485 | /* Copy over the MD5 key from the original socket */ | |
1486 | if ((key = tcp_v4_md5_do_lookup(sk, newinet->daddr)) != NULL) { | |
1487 | /* | |
1488 | * We're using one, so create a matching key | |
1489 | * on the newsk structure. If we fail to get | |
1490 | * memory, then we end up not copying the key | |
1491 | * across. Shucks. | |
1492 | */ | |
1493 | char *newkey = kmalloc(key->keylen, GFP_ATOMIC); | |
1494 | if (newkey) { | |
1495 | memcpy(newkey, key->key, key->keylen); | |
1496 | tcp_v4_md5_do_add(newsk, inet_sk(sk)->daddr, | |
1497 | newkey, key->keylen); | |
1498 | } | |
1499 | } | |
1500 | #endif | |
1501 | ||
f3f05f70 | 1502 | __inet_hash(&tcp_hashinfo, newsk, 0); |
2d8c4ce5 | 1503 | __inet_inherit_port(&tcp_hashinfo, sk, newsk); |
1da177e4 LT |
1504 | |
1505 | return newsk; | |
1506 | ||
1507 | exit_overflow: | |
1508 | NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); | |
1509 | exit: | |
1510 | NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); | |
1511 | dst_release(dst); | |
1512 | return NULL; | |
1513 | } | |
1514 | ||
1515 | static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) | |
1516 | { | |
1517 | struct tcphdr *th = skb->h.th; | |
1518 | struct iphdr *iph = skb->nh.iph; | |
1da177e4 | 1519 | struct sock *nsk; |
60236fdd | 1520 | struct request_sock **prev; |
1da177e4 | 1521 | /* Find possible connection requests. */ |
463c84b9 ACM |
1522 | struct request_sock *req = inet_csk_search_req(sk, &prev, th->source, |
1523 | iph->saddr, iph->daddr); | |
1da177e4 LT |
1524 | if (req) |
1525 | return tcp_check_req(sk, skb, req, prev); | |
1526 | ||
8f491069 HX |
1527 | nsk = inet_lookup_established(&tcp_hashinfo, skb->nh.iph->saddr, |
1528 | th->source, skb->nh.iph->daddr, | |
1529 | th->dest, inet_iif(skb)); | |
1da177e4 LT |
1530 | |
1531 | if (nsk) { | |
1532 | if (nsk->sk_state != TCP_TIME_WAIT) { | |
1533 | bh_lock_sock(nsk); | |
1534 | return nsk; | |
1535 | } | |
9469c7b4 | 1536 | inet_twsk_put(inet_twsk(nsk)); |
1da177e4 LT |
1537 | return NULL; |
1538 | } | |
1539 | ||
1540 | #ifdef CONFIG_SYN_COOKIES | |
1541 | if (!th->rst && !th->syn && th->ack) | |
1542 | sk = cookie_v4_check(sk, skb, &(IPCB(skb)->opt)); | |
1543 | #endif | |
1544 | return sk; | |
1545 | } | |
1546 | ||
b51655b9 | 1547 | static __sum16 tcp_v4_checksum_init(struct sk_buff *skb) |
1da177e4 | 1548 | { |
84fa7933 | 1549 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
1da177e4 | 1550 | if (!tcp_v4_check(skb->h.th, skb->len, skb->nh.iph->saddr, |
fb286bb2 HX |
1551 | skb->nh.iph->daddr, skb->csum)) { |
1552 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
1da177e4 | 1553 | return 0; |
fb286bb2 | 1554 | } |
1da177e4 | 1555 | } |
fb286bb2 HX |
1556 | |
1557 | skb->csum = csum_tcpudp_nofold(skb->nh.iph->saddr, skb->nh.iph->daddr, | |
1558 | skb->len, IPPROTO_TCP, 0); | |
1559 | ||
1da177e4 | 1560 | if (skb->len <= 76) { |
fb286bb2 | 1561 | return __skb_checksum_complete(skb); |
1da177e4 LT |
1562 | } |
1563 | return 0; | |
1564 | } | |
1565 | ||
1566 | ||
1567 | /* The socket must have it's spinlock held when we get | |
1568 | * here. | |
1569 | * | |
1570 | * We have a potential double-lock case here, so even when | |
1571 | * doing backlog processing we use the BH locking scheme. | |
1572 | * This is because we cannot sleep with the original spinlock | |
1573 | * held. | |
1574 | */ | |
1575 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) | |
1576 | { | |
cfb6eeb4 YH |
1577 | struct sock *rsk; |
1578 | #ifdef CONFIG_TCP_MD5SIG | |
1579 | /* | |
1580 | * We really want to reject the packet as early as possible | |
1581 | * if: | |
1582 | * o We're expecting an MD5'd packet and this is no MD5 tcp option | |
1583 | * o There is an MD5 option and we're not expecting one | |
1584 | */ | |
1585 | if (tcp_v4_inbound_md5_hash (sk, skb)) | |
1586 | goto discard; | |
1587 | #endif | |
1588 | ||
1da177e4 LT |
1589 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
1590 | TCP_CHECK_TIMER(sk); | |
cfb6eeb4 YH |
1591 | if (tcp_rcv_established(sk, skb, skb->h.th, skb->len)) { |
1592 | rsk = sk; | |
1da177e4 | 1593 | goto reset; |
cfb6eeb4 | 1594 | } |
1da177e4 LT |
1595 | TCP_CHECK_TIMER(sk); |
1596 | return 0; | |
1597 | } | |
1598 | ||
1599 | if (skb->len < (skb->h.th->doff << 2) || tcp_checksum_complete(skb)) | |
1600 | goto csum_err; | |
1601 | ||
1602 | if (sk->sk_state == TCP_LISTEN) { | |
1603 | struct sock *nsk = tcp_v4_hnd_req(sk, skb); | |
1604 | if (!nsk) | |
1605 | goto discard; | |
1606 | ||
1607 | if (nsk != sk) { | |
cfb6eeb4 YH |
1608 | if (tcp_child_process(sk, nsk, skb)) { |
1609 | rsk = nsk; | |
1da177e4 | 1610 | goto reset; |
cfb6eeb4 | 1611 | } |
1da177e4 LT |
1612 | return 0; |
1613 | } | |
1614 | } | |
1615 | ||
1616 | TCP_CHECK_TIMER(sk); | |
cfb6eeb4 YH |
1617 | if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len)) { |
1618 | rsk = sk; | |
1da177e4 | 1619 | goto reset; |
cfb6eeb4 | 1620 | } |
1da177e4 LT |
1621 | TCP_CHECK_TIMER(sk); |
1622 | return 0; | |
1623 | ||
1624 | reset: | |
cfb6eeb4 | 1625 | tcp_v4_send_reset(rsk, skb); |
1da177e4 LT |
1626 | discard: |
1627 | kfree_skb(skb); | |
1628 | /* Be careful here. If this function gets more complicated and | |
1629 | * gcc suffers from register pressure on the x86, sk (in %ebx) | |
1630 | * might be destroyed here. This current version compiles correctly, | |
1631 | * but you have been warned. | |
1632 | */ | |
1633 | return 0; | |
1634 | ||
1635 | csum_err: | |
1636 | TCP_INC_STATS_BH(TCP_MIB_INERRS); | |
1637 | goto discard; | |
1638 | } | |
1639 | ||
1640 | /* | |
1641 | * From tcp_input.c | |
1642 | */ | |
1643 | ||
1644 | int tcp_v4_rcv(struct sk_buff *skb) | |
1645 | { | |
1646 | struct tcphdr *th; | |
1647 | struct sock *sk; | |
1648 | int ret; | |
1649 | ||
1650 | if (skb->pkt_type != PACKET_HOST) | |
1651 | goto discard_it; | |
1652 | ||
1653 | /* Count it even if it's bad */ | |
1654 | TCP_INC_STATS_BH(TCP_MIB_INSEGS); | |
1655 | ||
1656 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | |
1657 | goto discard_it; | |
1658 | ||
1659 | th = skb->h.th; | |
1660 | ||
1661 | if (th->doff < sizeof(struct tcphdr) / 4) | |
1662 | goto bad_packet; | |
1663 | if (!pskb_may_pull(skb, th->doff * 4)) | |
1664 | goto discard_it; | |
1665 | ||
1666 | /* An explanation is required here, I think. | |
1667 | * Packet length and doff are validated by header prediction, | |
caa20d9a | 1668 | * provided case of th->doff==0 is eliminated. |
1da177e4 LT |
1669 | * So, we defer the checks. */ |
1670 | if ((skb->ip_summed != CHECKSUM_UNNECESSARY && | |
fb286bb2 | 1671 | tcp_v4_checksum_init(skb))) |
1da177e4 LT |
1672 | goto bad_packet; |
1673 | ||
1674 | th = skb->h.th; | |
1675 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); | |
1676 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | |
1677 | skb->len - th->doff * 4); | |
1678 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | |
1679 | TCP_SKB_CB(skb)->when = 0; | |
1680 | TCP_SKB_CB(skb)->flags = skb->nh.iph->tos; | |
1681 | TCP_SKB_CB(skb)->sacked = 0; | |
1682 | ||
e48c414e | 1683 | sk = __inet_lookup(&tcp_hashinfo, skb->nh.iph->saddr, th->source, |
8f491069 | 1684 | skb->nh.iph->daddr, th->dest, |
463c84b9 | 1685 | inet_iif(skb)); |
1da177e4 LT |
1686 | |
1687 | if (!sk) | |
1688 | goto no_tcp_socket; | |
1689 | ||
1690 | process: | |
1691 | if (sk->sk_state == TCP_TIME_WAIT) | |
1692 | goto do_time_wait; | |
1693 | ||
1694 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) | |
1695 | goto discard_and_relse; | |
b59c2701 | 1696 | nf_reset(skb); |
1da177e4 | 1697 | |
fda9ef5d | 1698 | if (sk_filter(sk, skb)) |
1da177e4 LT |
1699 | goto discard_and_relse; |
1700 | ||
1701 | skb->dev = NULL; | |
1702 | ||
c6366184 | 1703 | bh_lock_sock_nested(sk); |
1da177e4 LT |
1704 | ret = 0; |
1705 | if (!sock_owned_by_user(sk)) { | |
1a2449a8 CL |
1706 | #ifdef CONFIG_NET_DMA |
1707 | struct tcp_sock *tp = tcp_sk(sk); | |
1708 | if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) | |
1709 | tp->ucopy.dma_chan = get_softnet_dma(); | |
1710 | if (tp->ucopy.dma_chan) | |
1da177e4 | 1711 | ret = tcp_v4_do_rcv(sk, skb); |
1a2449a8 CL |
1712 | else |
1713 | #endif | |
1714 | { | |
1715 | if (!tcp_prequeue(sk, skb)) | |
1716 | ret = tcp_v4_do_rcv(sk, skb); | |
1717 | } | |
1da177e4 LT |
1718 | } else |
1719 | sk_add_backlog(sk, skb); | |
1720 | bh_unlock_sock(sk); | |
1721 | ||
1722 | sock_put(sk); | |
1723 | ||
1724 | return ret; | |
1725 | ||
1726 | no_tcp_socket: | |
1727 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) | |
1728 | goto discard_it; | |
1729 | ||
1730 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { | |
1731 | bad_packet: | |
1732 | TCP_INC_STATS_BH(TCP_MIB_INERRS); | |
1733 | } else { | |
cfb6eeb4 | 1734 | tcp_v4_send_reset(NULL, skb); |
1da177e4 LT |
1735 | } |
1736 | ||
1737 | discard_it: | |
1738 | /* Discard frame. */ | |
1739 | kfree_skb(skb); | |
1740 | return 0; | |
1741 | ||
1742 | discard_and_relse: | |
1743 | sock_put(sk); | |
1744 | goto discard_it; | |
1745 | ||
1746 | do_time_wait: | |
1747 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | |
9469c7b4 | 1748 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
1749 | goto discard_it; |
1750 | } | |
1751 | ||
1752 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { | |
1753 | TCP_INC_STATS_BH(TCP_MIB_INERRS); | |
9469c7b4 | 1754 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
1755 | goto discard_it; |
1756 | } | |
9469c7b4 | 1757 | switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { |
1da177e4 | 1758 | case TCP_TW_SYN: { |
33b62231 ACM |
1759 | struct sock *sk2 = inet_lookup_listener(&tcp_hashinfo, |
1760 | skb->nh.iph->daddr, | |
8f491069 | 1761 | th->dest, |
463c84b9 | 1762 | inet_iif(skb)); |
1da177e4 | 1763 | if (sk2) { |
9469c7b4 YH |
1764 | inet_twsk_deschedule(inet_twsk(sk), &tcp_death_row); |
1765 | inet_twsk_put(inet_twsk(sk)); | |
1da177e4 LT |
1766 | sk = sk2; |
1767 | goto process; | |
1768 | } | |
1769 | /* Fall through to ACK */ | |
1770 | } | |
1771 | case TCP_TW_ACK: | |
1772 | tcp_v4_timewait_ack(sk, skb); | |
1773 | break; | |
1774 | case TCP_TW_RST: | |
1775 | goto no_tcp_socket; | |
1776 | case TCP_TW_SUCCESS:; | |
1777 | } | |
1778 | goto discard_it; | |
1779 | } | |
1780 | ||
1da177e4 LT |
1781 | /* VJ's idea. Save last timestamp seen from this destination |
1782 | * and hold it at least for normal timewait interval to use for duplicate | |
1783 | * segment detection in subsequent connections, before they enter synchronized | |
1784 | * state. | |
1785 | */ | |
1786 | ||
1787 | int tcp_v4_remember_stamp(struct sock *sk) | |
1788 | { | |
1789 | struct inet_sock *inet = inet_sk(sk); | |
1790 | struct tcp_sock *tp = tcp_sk(sk); | |
1791 | struct rtable *rt = (struct rtable *)__sk_dst_get(sk); | |
1792 | struct inet_peer *peer = NULL; | |
1793 | int release_it = 0; | |
1794 | ||
1795 | if (!rt || rt->rt_dst != inet->daddr) { | |
1796 | peer = inet_getpeer(inet->daddr, 1); | |
1797 | release_it = 1; | |
1798 | } else { | |
1799 | if (!rt->peer) | |
1800 | rt_bind_peer(rt, 1); | |
1801 | peer = rt->peer; | |
1802 | } | |
1803 | ||
1804 | if (peer) { | |
1805 | if ((s32)(peer->tcp_ts - tp->rx_opt.ts_recent) <= 0 || | |
1806 | (peer->tcp_ts_stamp + TCP_PAWS_MSL < xtime.tv_sec && | |
1807 | peer->tcp_ts_stamp <= tp->rx_opt.ts_recent_stamp)) { | |
1808 | peer->tcp_ts_stamp = tp->rx_opt.ts_recent_stamp; | |
1809 | peer->tcp_ts = tp->rx_opt.ts_recent; | |
1810 | } | |
1811 | if (release_it) | |
1812 | inet_putpeer(peer); | |
1813 | return 1; | |
1814 | } | |
1815 | ||
1816 | return 0; | |
1817 | } | |
1818 | ||
8feaf0c0 | 1819 | int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw) |
1da177e4 | 1820 | { |
8feaf0c0 | 1821 | struct inet_peer *peer = inet_getpeer(tw->tw_daddr, 1); |
1da177e4 LT |
1822 | |
1823 | if (peer) { | |
8feaf0c0 ACM |
1824 | const struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); |
1825 | ||
1826 | if ((s32)(peer->tcp_ts - tcptw->tw_ts_recent) <= 0 || | |
1da177e4 | 1827 | (peer->tcp_ts_stamp + TCP_PAWS_MSL < xtime.tv_sec && |
8feaf0c0 ACM |
1828 | peer->tcp_ts_stamp <= tcptw->tw_ts_recent_stamp)) { |
1829 | peer->tcp_ts_stamp = tcptw->tw_ts_recent_stamp; | |
1830 | peer->tcp_ts = tcptw->tw_ts_recent; | |
1da177e4 LT |
1831 | } |
1832 | inet_putpeer(peer); | |
1833 | return 1; | |
1834 | } | |
1835 | ||
1836 | return 0; | |
1837 | } | |
1838 | ||
8292a17a | 1839 | struct inet_connection_sock_af_ops ipv4_specific = { |
543d9cfe ACM |
1840 | .queue_xmit = ip_queue_xmit, |
1841 | .send_check = tcp_v4_send_check, | |
1842 | .rebuild_header = inet_sk_rebuild_header, | |
1843 | .conn_request = tcp_v4_conn_request, | |
1844 | .syn_recv_sock = tcp_v4_syn_recv_sock, | |
1845 | .remember_stamp = tcp_v4_remember_stamp, | |
1846 | .net_header_len = sizeof(struct iphdr), | |
1847 | .setsockopt = ip_setsockopt, | |
1848 | .getsockopt = ip_getsockopt, | |
1849 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
1850 | .sockaddr_len = sizeof(struct sockaddr_in), | |
3fdadf7d | 1851 | #ifdef CONFIG_COMPAT |
543d9cfe ACM |
1852 | .compat_setsockopt = compat_ip_setsockopt, |
1853 | .compat_getsockopt = compat_ip_getsockopt, | |
3fdadf7d | 1854 | #endif |
1da177e4 LT |
1855 | }; |
1856 | ||
cfb6eeb4 YH |
1857 | struct tcp_sock_af_ops tcp_sock_ipv4_specific = { |
1858 | #ifdef CONFIG_TCP_MD5SIG | |
1859 | .md5_lookup = tcp_v4_md5_lookup, | |
1860 | .calc_md5_hash = tcp_v4_calc_md5_hash, | |
1861 | .md5_add = tcp_v4_md5_add_func, | |
1862 | .md5_parse = tcp_v4_parse_md5_keys, | |
1863 | #endif | |
1864 | }; | |
1865 | ||
1da177e4 LT |
1866 | /* NOTE: A lot of things set to zero explicitly by call to |
1867 | * sk_alloc() so need not be done here. | |
1868 | */ | |
1869 | static int tcp_v4_init_sock(struct sock *sk) | |
1870 | { | |
6687e988 | 1871 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
1872 | struct tcp_sock *tp = tcp_sk(sk); |
1873 | ||
1874 | skb_queue_head_init(&tp->out_of_order_queue); | |
1875 | tcp_init_xmit_timers(sk); | |
1876 | tcp_prequeue_init(tp); | |
1877 | ||
6687e988 | 1878 | icsk->icsk_rto = TCP_TIMEOUT_INIT; |
1da177e4 LT |
1879 | tp->mdev = TCP_TIMEOUT_INIT; |
1880 | ||
1881 | /* So many TCP implementations out there (incorrectly) count the | |
1882 | * initial SYN frame in their delayed-ACK and congestion control | |
1883 | * algorithms that we must have the following bandaid to talk | |
1884 | * efficiently to them. -DaveM | |
1885 | */ | |
1886 | tp->snd_cwnd = 2; | |
1887 | ||
1888 | /* See draft-stevens-tcpca-spec-01 for discussion of the | |
1889 | * initialization of these values. | |
1890 | */ | |
1891 | tp->snd_ssthresh = 0x7fffffff; /* Infinity */ | |
1892 | tp->snd_cwnd_clamp = ~0; | |
c1b4a7e6 | 1893 | tp->mss_cache = 536; |
1da177e4 LT |
1894 | |
1895 | tp->reordering = sysctl_tcp_reordering; | |
6687e988 | 1896 | icsk->icsk_ca_ops = &tcp_init_congestion_ops; |
1da177e4 LT |
1897 | |
1898 | sk->sk_state = TCP_CLOSE; | |
1899 | ||
1900 | sk->sk_write_space = sk_stream_write_space; | |
1901 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | |
1902 | ||
8292a17a | 1903 | icsk->icsk_af_ops = &ipv4_specific; |
d83d8461 | 1904 | icsk->icsk_sync_mss = tcp_sync_mss; |
cfb6eeb4 YH |
1905 | #ifdef CONFIG_TCP_MD5SIG |
1906 | tp->af_specific = &tcp_sock_ipv4_specific; | |
1907 | #endif | |
1da177e4 LT |
1908 | |
1909 | sk->sk_sndbuf = sysctl_tcp_wmem[1]; | |
1910 | sk->sk_rcvbuf = sysctl_tcp_rmem[1]; | |
1911 | ||
1912 | atomic_inc(&tcp_sockets_allocated); | |
1913 | ||
1914 | return 0; | |
1915 | } | |
1916 | ||
1917 | int tcp_v4_destroy_sock(struct sock *sk) | |
1918 | { | |
1919 | struct tcp_sock *tp = tcp_sk(sk); | |
1920 | ||
1921 | tcp_clear_xmit_timers(sk); | |
1922 | ||
6687e988 | 1923 | tcp_cleanup_congestion_control(sk); |
317a76f9 | 1924 | |
1da177e4 LT |
1925 | /* Cleanup up the write buffer. */ |
1926 | sk_stream_writequeue_purge(sk); | |
1927 | ||
1928 | /* Cleans up our, hopefully empty, out_of_order_queue. */ | |
1929 | __skb_queue_purge(&tp->out_of_order_queue); | |
1930 | ||
cfb6eeb4 YH |
1931 | #ifdef CONFIG_TCP_MD5SIG |
1932 | /* Clean up the MD5 key list, if any */ | |
1933 | if (tp->md5sig_info) { | |
1934 | tcp_v4_clear_md5_list(sk); | |
1935 | kfree(tp->md5sig_info); | |
1936 | tp->md5sig_info = NULL; | |
1937 | } | |
1938 | #endif | |
1939 | ||
1a2449a8 CL |
1940 | #ifdef CONFIG_NET_DMA |
1941 | /* Cleans up our sk_async_wait_queue */ | |
1942 | __skb_queue_purge(&sk->sk_async_wait_queue); | |
1943 | #endif | |
1944 | ||
1da177e4 LT |
1945 | /* Clean prequeue, it must be empty really */ |
1946 | __skb_queue_purge(&tp->ucopy.prequeue); | |
1947 | ||
1948 | /* Clean up a referenced TCP bind bucket. */ | |
463c84b9 | 1949 | if (inet_csk(sk)->icsk_bind_hash) |
2d8c4ce5 | 1950 | inet_put_port(&tcp_hashinfo, sk); |
1da177e4 LT |
1951 | |
1952 | /* | |
1953 | * If sendmsg cached page exists, toss it. | |
1954 | */ | |
1955 | if (sk->sk_sndmsg_page) { | |
1956 | __free_page(sk->sk_sndmsg_page); | |
1957 | sk->sk_sndmsg_page = NULL; | |
1958 | } | |
1959 | ||
1960 | atomic_dec(&tcp_sockets_allocated); | |
1961 | ||
1962 | return 0; | |
1963 | } | |
1964 | ||
1965 | EXPORT_SYMBOL(tcp_v4_destroy_sock); | |
1966 | ||
1967 | #ifdef CONFIG_PROC_FS | |
1968 | /* Proc filesystem TCP sock list dumping. */ | |
1969 | ||
8feaf0c0 | 1970 | static inline struct inet_timewait_sock *tw_head(struct hlist_head *head) |
1da177e4 LT |
1971 | { |
1972 | return hlist_empty(head) ? NULL : | |
8feaf0c0 | 1973 | list_entry(head->first, struct inet_timewait_sock, tw_node); |
1da177e4 LT |
1974 | } |
1975 | ||
8feaf0c0 | 1976 | static inline struct inet_timewait_sock *tw_next(struct inet_timewait_sock *tw) |
1da177e4 LT |
1977 | { |
1978 | return tw->tw_node.next ? | |
1979 | hlist_entry(tw->tw_node.next, typeof(*tw), tw_node) : NULL; | |
1980 | } | |
1981 | ||
1982 | static void *listening_get_next(struct seq_file *seq, void *cur) | |
1983 | { | |
463c84b9 | 1984 | struct inet_connection_sock *icsk; |
1da177e4 LT |
1985 | struct hlist_node *node; |
1986 | struct sock *sk = cur; | |
1987 | struct tcp_iter_state* st = seq->private; | |
1988 | ||
1989 | if (!sk) { | |
1990 | st->bucket = 0; | |
6e04e021 | 1991 | sk = sk_head(&tcp_hashinfo.listening_hash[0]); |
1da177e4 LT |
1992 | goto get_sk; |
1993 | } | |
1994 | ||
1995 | ++st->num; | |
1996 | ||
1997 | if (st->state == TCP_SEQ_STATE_OPENREQ) { | |
60236fdd | 1998 | struct request_sock *req = cur; |
1da177e4 | 1999 | |
72a3effa | 2000 | icsk = inet_csk(st->syn_wait_sk); |
1da177e4 LT |
2001 | req = req->dl_next; |
2002 | while (1) { | |
2003 | while (req) { | |
60236fdd | 2004 | if (req->rsk_ops->family == st->family) { |
1da177e4 LT |
2005 | cur = req; |
2006 | goto out; | |
2007 | } | |
2008 | req = req->dl_next; | |
2009 | } | |
72a3effa | 2010 | if (++st->sbucket >= icsk->icsk_accept_queue.listen_opt->nr_table_entries) |
1da177e4 LT |
2011 | break; |
2012 | get_req: | |
463c84b9 | 2013 | req = icsk->icsk_accept_queue.listen_opt->syn_table[st->sbucket]; |
1da177e4 LT |
2014 | } |
2015 | sk = sk_next(st->syn_wait_sk); | |
2016 | st->state = TCP_SEQ_STATE_LISTENING; | |
463c84b9 | 2017 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 | 2018 | } else { |
463c84b9 ACM |
2019 | icsk = inet_csk(sk); |
2020 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); | |
2021 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) | |
1da177e4 | 2022 | goto start_req; |
463c84b9 | 2023 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 LT |
2024 | sk = sk_next(sk); |
2025 | } | |
2026 | get_sk: | |
2027 | sk_for_each_from(sk, node) { | |
2028 | if (sk->sk_family == st->family) { | |
2029 | cur = sk; | |
2030 | goto out; | |
2031 | } | |
463c84b9 ACM |
2032 | icsk = inet_csk(sk); |
2033 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); | |
2034 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) { | |
1da177e4 LT |
2035 | start_req: |
2036 | st->uid = sock_i_uid(sk); | |
2037 | st->syn_wait_sk = sk; | |
2038 | st->state = TCP_SEQ_STATE_OPENREQ; | |
2039 | st->sbucket = 0; | |
2040 | goto get_req; | |
2041 | } | |
463c84b9 | 2042 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 | 2043 | } |
0f7ff927 | 2044 | if (++st->bucket < INET_LHTABLE_SIZE) { |
6e04e021 | 2045 | sk = sk_head(&tcp_hashinfo.listening_hash[st->bucket]); |
1da177e4 LT |
2046 | goto get_sk; |
2047 | } | |
2048 | cur = NULL; | |
2049 | out: | |
2050 | return cur; | |
2051 | } | |
2052 | ||
2053 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) | |
2054 | { | |
2055 | void *rc = listening_get_next(seq, NULL); | |
2056 | ||
2057 | while (rc && *pos) { | |
2058 | rc = listening_get_next(seq, rc); | |
2059 | --*pos; | |
2060 | } | |
2061 | return rc; | |
2062 | } | |
2063 | ||
2064 | static void *established_get_first(struct seq_file *seq) | |
2065 | { | |
2066 | struct tcp_iter_state* st = seq->private; | |
2067 | void *rc = NULL; | |
2068 | ||
6e04e021 | 2069 | for (st->bucket = 0; st->bucket < tcp_hashinfo.ehash_size; ++st->bucket) { |
1da177e4 LT |
2070 | struct sock *sk; |
2071 | struct hlist_node *node; | |
8feaf0c0 | 2072 | struct inet_timewait_sock *tw; |
1da177e4 LT |
2073 | |
2074 | /* We can reschedule _before_ having picked the target: */ | |
2075 | cond_resched_softirq(); | |
2076 | ||
6e04e021 ACM |
2077 | read_lock(&tcp_hashinfo.ehash[st->bucket].lock); |
2078 | sk_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { | |
1da177e4 LT |
2079 | if (sk->sk_family != st->family) { |
2080 | continue; | |
2081 | } | |
2082 | rc = sk; | |
2083 | goto out; | |
2084 | } | |
2085 | st->state = TCP_SEQ_STATE_TIME_WAIT; | |
8feaf0c0 ACM |
2086 | inet_twsk_for_each(tw, node, |
2087 | &tcp_hashinfo.ehash[st->bucket + tcp_hashinfo.ehash_size].chain) { | |
1da177e4 LT |
2088 | if (tw->tw_family != st->family) { |
2089 | continue; | |
2090 | } | |
2091 | rc = tw; | |
2092 | goto out; | |
2093 | } | |
6e04e021 | 2094 | read_unlock(&tcp_hashinfo.ehash[st->bucket].lock); |
1da177e4 LT |
2095 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2096 | } | |
2097 | out: | |
2098 | return rc; | |
2099 | } | |
2100 | ||
2101 | static void *established_get_next(struct seq_file *seq, void *cur) | |
2102 | { | |
2103 | struct sock *sk = cur; | |
8feaf0c0 | 2104 | struct inet_timewait_sock *tw; |
1da177e4 LT |
2105 | struct hlist_node *node; |
2106 | struct tcp_iter_state* st = seq->private; | |
2107 | ||
2108 | ++st->num; | |
2109 | ||
2110 | if (st->state == TCP_SEQ_STATE_TIME_WAIT) { | |
2111 | tw = cur; | |
2112 | tw = tw_next(tw); | |
2113 | get_tw: | |
2114 | while (tw && tw->tw_family != st->family) { | |
2115 | tw = tw_next(tw); | |
2116 | } | |
2117 | if (tw) { | |
2118 | cur = tw; | |
2119 | goto out; | |
2120 | } | |
6e04e021 | 2121 | read_unlock(&tcp_hashinfo.ehash[st->bucket].lock); |
1da177e4 LT |
2122 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2123 | ||
2124 | /* We can reschedule between buckets: */ | |
2125 | cond_resched_softirq(); | |
2126 | ||
6e04e021 ACM |
2127 | if (++st->bucket < tcp_hashinfo.ehash_size) { |
2128 | read_lock(&tcp_hashinfo.ehash[st->bucket].lock); | |
2129 | sk = sk_head(&tcp_hashinfo.ehash[st->bucket].chain); | |
1da177e4 LT |
2130 | } else { |
2131 | cur = NULL; | |
2132 | goto out; | |
2133 | } | |
2134 | } else | |
2135 | sk = sk_next(sk); | |
2136 | ||
2137 | sk_for_each_from(sk, node) { | |
2138 | if (sk->sk_family == st->family) | |
2139 | goto found; | |
2140 | } | |
2141 | ||
2142 | st->state = TCP_SEQ_STATE_TIME_WAIT; | |
6e04e021 | 2143 | tw = tw_head(&tcp_hashinfo.ehash[st->bucket + tcp_hashinfo.ehash_size].chain); |
1da177e4 LT |
2144 | goto get_tw; |
2145 | found: | |
2146 | cur = sk; | |
2147 | out: | |
2148 | return cur; | |
2149 | } | |
2150 | ||
2151 | static void *established_get_idx(struct seq_file *seq, loff_t pos) | |
2152 | { | |
2153 | void *rc = established_get_first(seq); | |
2154 | ||
2155 | while (rc && pos) { | |
2156 | rc = established_get_next(seq, rc); | |
2157 | --pos; | |
2158 | } | |
2159 | return rc; | |
2160 | } | |
2161 | ||
2162 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) | |
2163 | { | |
2164 | void *rc; | |
2165 | struct tcp_iter_state* st = seq->private; | |
2166 | ||
f3f05f70 | 2167 | inet_listen_lock(&tcp_hashinfo); |
1da177e4 LT |
2168 | st->state = TCP_SEQ_STATE_LISTENING; |
2169 | rc = listening_get_idx(seq, &pos); | |
2170 | ||
2171 | if (!rc) { | |
f3f05f70 | 2172 | inet_listen_unlock(&tcp_hashinfo); |
1da177e4 LT |
2173 | local_bh_disable(); |
2174 | st->state = TCP_SEQ_STATE_ESTABLISHED; | |
2175 | rc = established_get_idx(seq, pos); | |
2176 | } | |
2177 | ||
2178 | return rc; | |
2179 | } | |
2180 | ||
2181 | static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) | |
2182 | { | |
2183 | struct tcp_iter_state* st = seq->private; | |
2184 | st->state = TCP_SEQ_STATE_LISTENING; | |
2185 | st->num = 0; | |
2186 | return *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
2187 | } | |
2188 | ||
2189 | static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2190 | { | |
2191 | void *rc = NULL; | |
2192 | struct tcp_iter_state* st; | |
2193 | ||
2194 | if (v == SEQ_START_TOKEN) { | |
2195 | rc = tcp_get_idx(seq, 0); | |
2196 | goto out; | |
2197 | } | |
2198 | st = seq->private; | |
2199 | ||
2200 | switch (st->state) { | |
2201 | case TCP_SEQ_STATE_OPENREQ: | |
2202 | case TCP_SEQ_STATE_LISTENING: | |
2203 | rc = listening_get_next(seq, v); | |
2204 | if (!rc) { | |
f3f05f70 | 2205 | inet_listen_unlock(&tcp_hashinfo); |
1da177e4 LT |
2206 | local_bh_disable(); |
2207 | st->state = TCP_SEQ_STATE_ESTABLISHED; | |
2208 | rc = established_get_first(seq); | |
2209 | } | |
2210 | break; | |
2211 | case TCP_SEQ_STATE_ESTABLISHED: | |
2212 | case TCP_SEQ_STATE_TIME_WAIT: | |
2213 | rc = established_get_next(seq, v); | |
2214 | break; | |
2215 | } | |
2216 | out: | |
2217 | ++*pos; | |
2218 | return rc; | |
2219 | } | |
2220 | ||
2221 | static void tcp_seq_stop(struct seq_file *seq, void *v) | |
2222 | { | |
2223 | struct tcp_iter_state* st = seq->private; | |
2224 | ||
2225 | switch (st->state) { | |
2226 | case TCP_SEQ_STATE_OPENREQ: | |
2227 | if (v) { | |
463c84b9 ACM |
2228 | struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk); |
2229 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); | |
1da177e4 LT |
2230 | } |
2231 | case TCP_SEQ_STATE_LISTENING: | |
2232 | if (v != SEQ_START_TOKEN) | |
f3f05f70 | 2233 | inet_listen_unlock(&tcp_hashinfo); |
1da177e4 LT |
2234 | break; |
2235 | case TCP_SEQ_STATE_TIME_WAIT: | |
2236 | case TCP_SEQ_STATE_ESTABLISHED: | |
2237 | if (v) | |
6e04e021 | 2238 | read_unlock(&tcp_hashinfo.ehash[st->bucket].lock); |
1da177e4 LT |
2239 | local_bh_enable(); |
2240 | break; | |
2241 | } | |
2242 | } | |
2243 | ||
2244 | static int tcp_seq_open(struct inode *inode, struct file *file) | |
2245 | { | |
2246 | struct tcp_seq_afinfo *afinfo = PDE(inode)->data; | |
2247 | struct seq_file *seq; | |
2248 | struct tcp_iter_state *s; | |
2249 | int rc; | |
2250 | ||
2251 | if (unlikely(afinfo == NULL)) | |
2252 | return -EINVAL; | |
2253 | ||
0da974f4 | 2254 | s = kzalloc(sizeof(*s), GFP_KERNEL); |
1da177e4 LT |
2255 | if (!s) |
2256 | return -ENOMEM; | |
1da177e4 LT |
2257 | s->family = afinfo->family; |
2258 | s->seq_ops.start = tcp_seq_start; | |
2259 | s->seq_ops.next = tcp_seq_next; | |
2260 | s->seq_ops.show = afinfo->seq_show; | |
2261 | s->seq_ops.stop = tcp_seq_stop; | |
2262 | ||
2263 | rc = seq_open(file, &s->seq_ops); | |
2264 | if (rc) | |
2265 | goto out_kfree; | |
2266 | seq = file->private_data; | |
2267 | seq->private = s; | |
2268 | out: | |
2269 | return rc; | |
2270 | out_kfree: | |
2271 | kfree(s); | |
2272 | goto out; | |
2273 | } | |
2274 | ||
2275 | int tcp_proc_register(struct tcp_seq_afinfo *afinfo) | |
2276 | { | |
2277 | int rc = 0; | |
2278 | struct proc_dir_entry *p; | |
2279 | ||
2280 | if (!afinfo) | |
2281 | return -EINVAL; | |
2282 | afinfo->seq_fops->owner = afinfo->owner; | |
2283 | afinfo->seq_fops->open = tcp_seq_open; | |
2284 | afinfo->seq_fops->read = seq_read; | |
2285 | afinfo->seq_fops->llseek = seq_lseek; | |
2286 | afinfo->seq_fops->release = seq_release_private; | |
2287 | ||
2288 | p = proc_net_fops_create(afinfo->name, S_IRUGO, afinfo->seq_fops); | |
2289 | if (p) | |
2290 | p->data = afinfo; | |
2291 | else | |
2292 | rc = -ENOMEM; | |
2293 | return rc; | |
2294 | } | |
2295 | ||
2296 | void tcp_proc_unregister(struct tcp_seq_afinfo *afinfo) | |
2297 | { | |
2298 | if (!afinfo) | |
2299 | return; | |
2300 | proc_net_remove(afinfo->name); | |
2301 | memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops)); | |
2302 | } | |
2303 | ||
60236fdd | 2304 | static void get_openreq4(struct sock *sk, struct request_sock *req, |
1da177e4 LT |
2305 | char *tmpbuf, int i, int uid) |
2306 | { | |
2e6599cb | 2307 | const struct inet_request_sock *ireq = inet_rsk(req); |
1da177e4 LT |
2308 | int ttd = req->expires - jiffies; |
2309 | ||
2310 | sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" | |
2311 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %p", | |
2312 | i, | |
2e6599cb | 2313 | ireq->loc_addr, |
1da177e4 | 2314 | ntohs(inet_sk(sk)->sport), |
2e6599cb ACM |
2315 | ireq->rmt_addr, |
2316 | ntohs(ireq->rmt_port), | |
1da177e4 LT |
2317 | TCP_SYN_RECV, |
2318 | 0, 0, /* could print option size, but that is af dependent. */ | |
2319 | 1, /* timers active (only the expire timer) */ | |
2320 | jiffies_to_clock_t(ttd), | |
2321 | req->retrans, | |
2322 | uid, | |
2323 | 0, /* non standard timer */ | |
2324 | 0, /* open_requests have no inode */ | |
2325 | atomic_read(&sk->sk_refcnt), | |
2326 | req); | |
2327 | } | |
2328 | ||
2329 | static void get_tcp4_sock(struct sock *sp, char *tmpbuf, int i) | |
2330 | { | |
2331 | int timer_active; | |
2332 | unsigned long timer_expires; | |
2333 | struct tcp_sock *tp = tcp_sk(sp); | |
463c84b9 | 2334 | const struct inet_connection_sock *icsk = inet_csk(sp); |
1da177e4 | 2335 | struct inet_sock *inet = inet_sk(sp); |
714e85be AV |
2336 | __be32 dest = inet->daddr; |
2337 | __be32 src = inet->rcv_saddr; | |
1da177e4 LT |
2338 | __u16 destp = ntohs(inet->dport); |
2339 | __u16 srcp = ntohs(inet->sport); | |
2340 | ||
463c84b9 | 2341 | if (icsk->icsk_pending == ICSK_TIME_RETRANS) { |
1da177e4 | 2342 | timer_active = 1; |
463c84b9 ACM |
2343 | timer_expires = icsk->icsk_timeout; |
2344 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | |
1da177e4 | 2345 | timer_active = 4; |
463c84b9 | 2346 | timer_expires = icsk->icsk_timeout; |
1da177e4 LT |
2347 | } else if (timer_pending(&sp->sk_timer)) { |
2348 | timer_active = 2; | |
2349 | timer_expires = sp->sk_timer.expires; | |
2350 | } else { | |
2351 | timer_active = 0; | |
2352 | timer_expires = jiffies; | |
2353 | } | |
2354 | ||
2355 | sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " | |
2356 | "%08X %5d %8d %lu %d %p %u %u %u %u %d", | |
2357 | i, src, srcp, dest, destp, sp->sk_state, | |
47da8ee6 SS |
2358 | tp->write_seq - tp->snd_una, |
2359 | (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq), | |
1da177e4 LT |
2360 | timer_active, |
2361 | jiffies_to_clock_t(timer_expires - jiffies), | |
463c84b9 | 2362 | icsk->icsk_retransmits, |
1da177e4 | 2363 | sock_i_uid(sp), |
6687e988 | 2364 | icsk->icsk_probes_out, |
1da177e4 LT |
2365 | sock_i_ino(sp), |
2366 | atomic_read(&sp->sk_refcnt), sp, | |
463c84b9 ACM |
2367 | icsk->icsk_rto, |
2368 | icsk->icsk_ack.ato, | |
2369 | (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, | |
1da177e4 LT |
2370 | tp->snd_cwnd, |
2371 | tp->snd_ssthresh >= 0xFFFF ? -1 : tp->snd_ssthresh); | |
2372 | } | |
2373 | ||
8feaf0c0 | 2374 | static void get_timewait4_sock(struct inet_timewait_sock *tw, char *tmpbuf, int i) |
1da177e4 | 2375 | { |
23f33c2d | 2376 | __be32 dest, src; |
1da177e4 LT |
2377 | __u16 destp, srcp; |
2378 | int ttd = tw->tw_ttd - jiffies; | |
2379 | ||
2380 | if (ttd < 0) | |
2381 | ttd = 0; | |
2382 | ||
2383 | dest = tw->tw_daddr; | |
2384 | src = tw->tw_rcv_saddr; | |
2385 | destp = ntohs(tw->tw_dport); | |
2386 | srcp = ntohs(tw->tw_sport); | |
2387 | ||
2388 | sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" | |
2389 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p", | |
2390 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, | |
2391 | 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, | |
2392 | atomic_read(&tw->tw_refcnt), tw); | |
2393 | } | |
2394 | ||
2395 | #define TMPSZ 150 | |
2396 | ||
2397 | static int tcp4_seq_show(struct seq_file *seq, void *v) | |
2398 | { | |
2399 | struct tcp_iter_state* st; | |
2400 | char tmpbuf[TMPSZ + 1]; | |
2401 | ||
2402 | if (v == SEQ_START_TOKEN) { | |
2403 | seq_printf(seq, "%-*s\n", TMPSZ - 1, | |
2404 | " sl local_address rem_address st tx_queue " | |
2405 | "rx_queue tr tm->when retrnsmt uid timeout " | |
2406 | "inode"); | |
2407 | goto out; | |
2408 | } | |
2409 | st = seq->private; | |
2410 | ||
2411 | switch (st->state) { | |
2412 | case TCP_SEQ_STATE_LISTENING: | |
2413 | case TCP_SEQ_STATE_ESTABLISHED: | |
2414 | get_tcp4_sock(v, tmpbuf, st->num); | |
2415 | break; | |
2416 | case TCP_SEQ_STATE_OPENREQ: | |
2417 | get_openreq4(st->syn_wait_sk, v, tmpbuf, st->num, st->uid); | |
2418 | break; | |
2419 | case TCP_SEQ_STATE_TIME_WAIT: | |
2420 | get_timewait4_sock(v, tmpbuf, st->num); | |
2421 | break; | |
2422 | } | |
2423 | seq_printf(seq, "%-*s\n", TMPSZ - 1, tmpbuf); | |
2424 | out: | |
2425 | return 0; | |
2426 | } | |
2427 | ||
2428 | static struct file_operations tcp4_seq_fops; | |
2429 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { | |
2430 | .owner = THIS_MODULE, | |
2431 | .name = "tcp", | |
2432 | .family = AF_INET, | |
2433 | .seq_show = tcp4_seq_show, | |
2434 | .seq_fops = &tcp4_seq_fops, | |
2435 | }; | |
2436 | ||
2437 | int __init tcp4_proc_init(void) | |
2438 | { | |
2439 | return tcp_proc_register(&tcp4_seq_afinfo); | |
2440 | } | |
2441 | ||
2442 | void tcp4_proc_exit(void) | |
2443 | { | |
2444 | tcp_proc_unregister(&tcp4_seq_afinfo); | |
2445 | } | |
2446 | #endif /* CONFIG_PROC_FS */ | |
2447 | ||
2448 | struct proto tcp_prot = { | |
2449 | .name = "TCP", | |
2450 | .owner = THIS_MODULE, | |
2451 | .close = tcp_close, | |
2452 | .connect = tcp_v4_connect, | |
2453 | .disconnect = tcp_disconnect, | |
463c84b9 | 2454 | .accept = inet_csk_accept, |
1da177e4 LT |
2455 | .ioctl = tcp_ioctl, |
2456 | .init = tcp_v4_init_sock, | |
2457 | .destroy = tcp_v4_destroy_sock, | |
2458 | .shutdown = tcp_shutdown, | |
2459 | .setsockopt = tcp_setsockopt, | |
2460 | .getsockopt = tcp_getsockopt, | |
2461 | .sendmsg = tcp_sendmsg, | |
2462 | .recvmsg = tcp_recvmsg, | |
2463 | .backlog_rcv = tcp_v4_do_rcv, | |
2464 | .hash = tcp_v4_hash, | |
2465 | .unhash = tcp_unhash, | |
2466 | .get_port = tcp_v4_get_port, | |
2467 | .enter_memory_pressure = tcp_enter_memory_pressure, | |
2468 | .sockets_allocated = &tcp_sockets_allocated, | |
0a5578cf | 2469 | .orphan_count = &tcp_orphan_count, |
1da177e4 LT |
2470 | .memory_allocated = &tcp_memory_allocated, |
2471 | .memory_pressure = &tcp_memory_pressure, | |
2472 | .sysctl_mem = sysctl_tcp_mem, | |
2473 | .sysctl_wmem = sysctl_tcp_wmem, | |
2474 | .sysctl_rmem = sysctl_tcp_rmem, | |
2475 | .max_header = MAX_TCP_HEADER, | |
2476 | .obj_size = sizeof(struct tcp_sock), | |
6d6ee43e | 2477 | .twsk_prot = &tcp_timewait_sock_ops, |
60236fdd | 2478 | .rsk_prot = &tcp_request_sock_ops, |
543d9cfe ACM |
2479 | #ifdef CONFIG_COMPAT |
2480 | .compat_setsockopt = compat_tcp_setsockopt, | |
2481 | .compat_getsockopt = compat_tcp_getsockopt, | |
2482 | #endif | |
1da177e4 LT |
2483 | }; |
2484 | ||
1da177e4 LT |
2485 | void __init tcp_v4_init(struct net_proto_family *ops) |
2486 | { | |
c4d93909 | 2487 | if (inet_csk_ctl_sock_create(&tcp_socket, PF_INET, SOCK_RAW, IPPROTO_TCP) < 0) |
1da177e4 | 2488 | panic("Failed to create the TCP control socket.\n"); |
1da177e4 LT |
2489 | } |
2490 | ||
2491 | EXPORT_SYMBOL(ipv4_specific); | |
1da177e4 | 2492 | EXPORT_SYMBOL(tcp_hashinfo); |
1da177e4 | 2493 | EXPORT_SYMBOL(tcp_prot); |
1da177e4 LT |
2494 | EXPORT_SYMBOL(tcp_unhash); |
2495 | EXPORT_SYMBOL(tcp_v4_conn_request); | |
2496 | EXPORT_SYMBOL(tcp_v4_connect); | |
2497 | EXPORT_SYMBOL(tcp_v4_do_rcv); | |
1da177e4 LT |
2498 | EXPORT_SYMBOL(tcp_v4_remember_stamp); |
2499 | EXPORT_SYMBOL(tcp_v4_send_check); | |
2500 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); | |
2501 | ||
2502 | #ifdef CONFIG_PROC_FS | |
2503 | EXPORT_SYMBOL(tcp_proc_register); | |
2504 | EXPORT_SYMBOL(tcp_proc_unregister); | |
2505 | #endif | |
2506 | EXPORT_SYMBOL(sysctl_local_port_range); | |
1da177e4 | 2507 | EXPORT_SYMBOL(sysctl_tcp_low_latency); |
1da177e4 | 2508 |