Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 39 | * request_sock handling and moved |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | * most of it into the af independent code. |
| 41 | * Added tail drop and some other bugfixes. |
Stephen Hemminger | caa20d9a | 2005-11-10 17:13:47 -0800 | [diff] [blame] | 42 | * Added new listen semantics. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
| 55 | #include <linux/config.h> |
| 56 | |
| 57 | #include <linux/types.h> |
| 58 | #include <linux/fcntl.h> |
| 59 | #include <linux/module.h> |
| 60 | #include <linux/random.h> |
| 61 | #include <linux/cache.h> |
| 62 | #include <linux/jhash.h> |
| 63 | #include <linux/init.h> |
| 64 | #include <linux/times.h> |
| 65 | |
| 66 | #include <net/icmp.h> |
Arnaldo Carvalho de Melo | 304a161 | 2005-08-09 19:59:20 -0700 | [diff] [blame] | 67 | #include <net/inet_hashtables.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | #include <net/tcp.h> |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 69 | #include <net/transp_v6.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | #include <net/ipv6.h> |
| 71 | #include <net/inet_common.h> |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 72 | #include <net/timewait_sock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | #include <net/xfrm.h> |
| 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | int sysctl_tcp_tw_reuse; |
| 82 | int sysctl_tcp_low_latency; |
| 83 | |
| 84 | /* Check TCP sequence numbers in ICMP packets. */ |
| 85 | #define ICMP_MIN_LENGTH 8 |
| 86 | |
| 87 | /* Socket used for sending RSTs */ |
| 88 | static struct socket *tcp_socket; |
| 89 | |
Arnaldo Carvalho de Melo | 8292a17 | 2005-12-13 23:15:52 -0800 | [diff] [blame] | 90 | void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
Arnaldo Carvalho de Melo | 0f7ff92 | 2005-08-09 19:59:44 -0700 | [diff] [blame] | 92 | struct inet_hashinfo __cacheline_aligned tcp_hashinfo = { |
| 93 | .lhash_lock = RW_LOCK_UNLOCKED, |
| 94 | .lhash_users = ATOMIC_INIT(0), |
| 95 | .lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(tcp_hashinfo.lhash_wait), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | }; |
| 97 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 98 | static int tcp_v4_get_port(struct sock *sk, unsigned short snum) |
| 99 | { |
Arnaldo Carvalho de Melo | 971af18 | 2005-12-13 23:14:47 -0800 | [diff] [blame] | 100 | return inet_csk_get_port(&tcp_hashinfo, sk, snum, |
| 101 | inet_csk_bind_conflict); |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 102 | } |
| 103 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | static void tcp_v4_hash(struct sock *sk) |
| 105 | { |
Arnaldo Carvalho de Melo | 81849d1 | 2005-08-09 20:08:50 -0700 | [diff] [blame] | 106 | inet_hash(&tcp_hashinfo, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | } |
| 108 | |
| 109 | void tcp_unhash(struct sock *sk) |
| 110 | { |
Arnaldo Carvalho de Melo | 81849d1 | 2005-08-09 20:08:50 -0700 | [diff] [blame] | 111 | inet_unhash(&tcp_hashinfo, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | } |
| 113 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | static inline __u32 tcp_v4_init_sequence(struct sock *sk, struct sk_buff *skb) |
| 115 | { |
| 116 | return secure_tcp_sequence_number(skb->nh.iph->daddr, |
| 117 | skb->nh.iph->saddr, |
| 118 | skb->h.th->dest, |
| 119 | skb->h.th->source); |
| 120 | } |
| 121 | |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 122 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) |
| 123 | { |
| 124 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); |
| 125 | struct tcp_sock *tp = tcp_sk(sk); |
| 126 | |
| 127 | /* With PAWS, it is safe from the viewpoint |
| 128 | of data integrity. Even without PAWS it is safe provided sequence |
| 129 | spaces do not overlap i.e. at data rates <= 80Mbit/sec. |
| 130 | |
| 131 | Actually, the idea is close to VJ's one, only timestamp cache is |
| 132 | held not per host, but per port pair and TW bucket is used as state |
| 133 | holder. |
| 134 | |
| 135 | If TW bucket has been already destroyed we fall back to VJ's scheme |
| 136 | and use initial timestamp retrieved from peer table. |
| 137 | */ |
| 138 | if (tcptw->tw_ts_recent_stamp && |
| 139 | (twp == NULL || (sysctl_tcp_tw_reuse && |
| 140 | xtime.tv_sec - tcptw->tw_ts_recent_stamp > 1))) { |
| 141 | tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; |
| 142 | if (tp->write_seq == 0) |
| 143 | tp->write_seq = 1; |
| 144 | tp->rx_opt.ts_recent = tcptw->tw_ts_recent; |
| 145 | tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; |
| 146 | sock_hold(sktw); |
| 147 | return 1; |
| 148 | } |
| 149 | |
| 150 | return 0; |
| 151 | } |
| 152 | |
| 153 | EXPORT_SYMBOL_GPL(tcp_twsk_unique); |
| 154 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | /* This will initiate an outgoing connection. */ |
| 156 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
| 157 | { |
| 158 | struct inet_sock *inet = inet_sk(sk); |
| 159 | struct tcp_sock *tp = tcp_sk(sk); |
| 160 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
| 161 | struct rtable *rt; |
| 162 | u32 daddr, nexthop; |
| 163 | int tmp; |
| 164 | int err; |
| 165 | |
| 166 | if (addr_len < sizeof(struct sockaddr_in)) |
| 167 | return -EINVAL; |
| 168 | |
| 169 | if (usin->sin_family != AF_INET) |
| 170 | return -EAFNOSUPPORT; |
| 171 | |
| 172 | nexthop = daddr = usin->sin_addr.s_addr; |
| 173 | if (inet->opt && inet->opt->srr) { |
| 174 | if (!daddr) |
| 175 | return -EINVAL; |
| 176 | nexthop = inet->opt->faddr; |
| 177 | } |
| 178 | |
| 179 | tmp = ip_route_connect(&rt, nexthop, inet->saddr, |
| 180 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
| 181 | IPPROTO_TCP, |
| 182 | inet->sport, usin->sin_port, sk); |
| 183 | if (tmp < 0) |
| 184 | return tmp; |
| 185 | |
| 186 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { |
| 187 | ip_rt_put(rt); |
| 188 | return -ENETUNREACH; |
| 189 | } |
| 190 | |
| 191 | if (!inet->opt || !inet->opt->srr) |
| 192 | daddr = rt->rt_dst; |
| 193 | |
| 194 | if (!inet->saddr) |
| 195 | inet->saddr = rt->rt_src; |
| 196 | inet->rcv_saddr = inet->saddr; |
| 197 | |
| 198 | if (tp->rx_opt.ts_recent_stamp && inet->daddr != daddr) { |
| 199 | /* Reset inherited state */ |
| 200 | tp->rx_opt.ts_recent = 0; |
| 201 | tp->rx_opt.ts_recent_stamp = 0; |
| 202 | tp->write_seq = 0; |
| 203 | } |
| 204 | |
Arnaldo Carvalho de Melo | 295ff7e | 2005-08-09 20:44:40 -0700 | [diff] [blame] | 205 | if (tcp_death_row.sysctl_tw_recycle && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | !tp->rx_opt.ts_recent_stamp && rt->rt_dst == daddr) { |
| 207 | struct inet_peer *peer = rt_get_peer(rt); |
| 208 | |
| 209 | /* VJ's idea. We save last timestamp seen from |
| 210 | * the destination in peer table, when entering state TIME-WAIT |
| 211 | * and initialize rx_opt.ts_recent from it, when trying new connection. |
| 212 | */ |
| 213 | |
| 214 | if (peer && peer->tcp_ts_stamp + TCP_PAWS_MSL >= xtime.tv_sec) { |
| 215 | tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp; |
| 216 | tp->rx_opt.ts_recent = peer->tcp_ts; |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | inet->dport = usin->sin_port; |
| 221 | inet->daddr = daddr; |
| 222 | |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 223 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | if (inet->opt) |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 225 | inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | |
| 227 | tp->rx_opt.mss_clamp = 536; |
| 228 | |
| 229 | /* Socket identity is still unknown (sport may be zero). |
| 230 | * However we set state to SYN-SENT and not releasing socket |
| 231 | * lock select source port, enter ourselves into the hash tables and |
| 232 | * complete initialization after this. |
| 233 | */ |
| 234 | tcp_set_state(sk, TCP_SYN_SENT); |
Arnaldo Carvalho de Melo | a7f5e7f | 2005-12-13 23:25:31 -0800 | [diff] [blame] | 235 | err = inet_hash_connect(&tcp_death_row, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | if (err) |
| 237 | goto failure; |
| 238 | |
Patrick McHardy | 5d39a79 | 2006-01-31 17:35:35 -0800 | [diff] [blame] | 239 | err = ip_route_newports(&rt, IPPROTO_TCP, inet->sport, inet->dport, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | if (err) |
| 241 | goto failure; |
| 242 | |
| 243 | /* OK, now commit destination to socket. */ |
Arnaldo Carvalho de Melo | 6cbb0df | 2005-08-09 19:49:02 -0700 | [diff] [blame] | 244 | sk_setup_caps(sk, &rt->u.dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | |
| 246 | if (!tp->write_seq) |
| 247 | tp->write_seq = secure_tcp_sequence_number(inet->saddr, |
| 248 | inet->daddr, |
| 249 | inet->sport, |
| 250 | usin->sin_port); |
| 251 | |
| 252 | inet->id = tp->write_seq ^ jiffies; |
| 253 | |
| 254 | err = tcp_connect(sk); |
| 255 | rt = NULL; |
| 256 | if (err) |
| 257 | goto failure; |
| 258 | |
| 259 | return 0; |
| 260 | |
| 261 | failure: |
| 262 | /* This unhashes the socket and releases the local port, if necessary. */ |
| 263 | tcp_set_state(sk, TCP_CLOSE); |
| 264 | ip_rt_put(rt); |
| 265 | sk->sk_route_caps = 0; |
| 266 | inet->dport = 0; |
| 267 | return err; |
| 268 | } |
| 269 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | /* |
| 271 | * This routine does path mtu discovery as defined in RFC1191. |
| 272 | */ |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 273 | static void do_pmtu_discovery(struct sock *sk, struct iphdr *iph, u32 mtu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | { |
| 275 | struct dst_entry *dst; |
| 276 | struct inet_sock *inet = inet_sk(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | |
| 278 | /* We are not interested in TCP_LISTEN and open_requests (SYN-ACKs |
| 279 | * send out by Linux are always <576bytes so they should go through |
| 280 | * unfragmented). |
| 281 | */ |
| 282 | if (sk->sk_state == TCP_LISTEN) |
| 283 | return; |
| 284 | |
| 285 | /* We don't check in the destentry if pmtu discovery is forbidden |
| 286 | * on this route. We just assume that no packet_to_big packets |
| 287 | * are send back when pmtu discovery is not active. |
| 288 | * There is a small race when the user changes this flag in the |
| 289 | * route, but I think that's acceptable. |
| 290 | */ |
| 291 | if ((dst = __sk_dst_check(sk, 0)) == NULL) |
| 292 | return; |
| 293 | |
| 294 | dst->ops->update_pmtu(dst, mtu); |
| 295 | |
| 296 | /* Something is about to be wrong... Remember soft error |
| 297 | * for the case, if this connection will not able to recover. |
| 298 | */ |
| 299 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) |
| 300 | sk->sk_err_soft = EMSGSIZE; |
| 301 | |
| 302 | mtu = dst_mtu(dst); |
| 303 | |
| 304 | if (inet->pmtudisc != IP_PMTUDISC_DONT && |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 305 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | tcp_sync_mss(sk, mtu); |
| 307 | |
| 308 | /* Resend the TCP packet because it's |
| 309 | * clear that the old packet has been |
| 310 | * dropped. This is the new "fast" path mtu |
| 311 | * discovery. |
| 312 | */ |
| 313 | tcp_simple_retransmit(sk); |
| 314 | } /* else let the usual retransmit timer handle it */ |
| 315 | } |
| 316 | |
| 317 | /* |
| 318 | * This routine is called by the ICMP module when it gets some |
| 319 | * sort of error condition. If err < 0 then the socket should |
| 320 | * be closed and the error returned to the user. If err > 0 |
| 321 | * it's just the icmp type << 8 | icmp code. After adjustment |
| 322 | * header points to the first 8 bytes of the tcp header. We need |
| 323 | * to find the appropriate port. |
| 324 | * |
| 325 | * The locking strategy used here is very "optimistic". When |
| 326 | * someone else accesses the socket the ICMP is just dropped |
| 327 | * and for some paths there is no check at all. |
| 328 | * A more general error queue to queue errors for later handling |
| 329 | * is probably better. |
| 330 | * |
| 331 | */ |
| 332 | |
| 333 | void tcp_v4_err(struct sk_buff *skb, u32 info) |
| 334 | { |
| 335 | struct iphdr *iph = (struct iphdr *)skb->data; |
| 336 | struct tcphdr *th = (struct tcphdr *)(skb->data + (iph->ihl << 2)); |
| 337 | struct tcp_sock *tp; |
| 338 | struct inet_sock *inet; |
| 339 | int type = skb->h.icmph->type; |
| 340 | int code = skb->h.icmph->code; |
| 341 | struct sock *sk; |
| 342 | __u32 seq; |
| 343 | int err; |
| 344 | |
| 345 | if (skb->len < (iph->ihl << 2) + 8) { |
| 346 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); |
| 347 | return; |
| 348 | } |
| 349 | |
Arnaldo Carvalho de Melo | e48c414 | 2005-08-09 20:09:46 -0700 | [diff] [blame] | 350 | sk = inet_lookup(&tcp_hashinfo, iph->daddr, th->dest, iph->saddr, |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 351 | th->source, inet_iif(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | if (!sk) { |
| 353 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); |
| 354 | return; |
| 355 | } |
| 356 | if (sk->sk_state == TCP_TIME_WAIT) { |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 357 | inet_twsk_put((struct inet_timewait_sock *)sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | return; |
| 359 | } |
| 360 | |
| 361 | bh_lock_sock(sk); |
| 362 | /* If too many ICMPs get dropped on busy |
| 363 | * servers this needs to be solved differently. |
| 364 | */ |
| 365 | if (sock_owned_by_user(sk)) |
| 366 | NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); |
| 367 | |
| 368 | if (sk->sk_state == TCP_CLOSE) |
| 369 | goto out; |
| 370 | |
| 371 | tp = tcp_sk(sk); |
| 372 | seq = ntohl(th->seq); |
| 373 | if (sk->sk_state != TCP_LISTEN && |
| 374 | !between(seq, tp->snd_una, tp->snd_nxt)) { |
| 375 | NET_INC_STATS(LINUX_MIB_OUTOFWINDOWICMPS); |
| 376 | goto out; |
| 377 | } |
| 378 | |
| 379 | switch (type) { |
| 380 | case ICMP_SOURCE_QUENCH: |
| 381 | /* Just silently ignore these. */ |
| 382 | goto out; |
| 383 | case ICMP_PARAMETERPROB: |
| 384 | err = EPROTO; |
| 385 | break; |
| 386 | case ICMP_DEST_UNREACH: |
| 387 | if (code > NR_ICMP_UNREACH) |
| 388 | goto out; |
| 389 | |
| 390 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ |
| 391 | if (!sock_owned_by_user(sk)) |
| 392 | do_pmtu_discovery(sk, iph, info); |
| 393 | goto out; |
| 394 | } |
| 395 | |
| 396 | err = icmp_err_convert[code].errno; |
| 397 | break; |
| 398 | case ICMP_TIME_EXCEEDED: |
| 399 | err = EHOSTUNREACH; |
| 400 | break; |
| 401 | default: |
| 402 | goto out; |
| 403 | } |
| 404 | |
| 405 | switch (sk->sk_state) { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 406 | struct request_sock *req, **prev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | case TCP_LISTEN: |
| 408 | if (sock_owned_by_user(sk)) |
| 409 | goto out; |
| 410 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 411 | req = inet_csk_search_req(sk, &prev, th->dest, |
| 412 | iph->daddr, iph->saddr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | if (!req) |
| 414 | goto out; |
| 415 | |
| 416 | /* ICMPs are not backlogged, hence we cannot get |
| 417 | an established socket here. |
| 418 | */ |
| 419 | BUG_TRAP(!req->sk); |
| 420 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 421 | if (seq != tcp_rsk(req)->snt_isn) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); |
| 423 | goto out; |
| 424 | } |
| 425 | |
| 426 | /* |
| 427 | * Still in SYN_RECV, just remove it silently. |
| 428 | * There is no good way to pass the error to the newly |
| 429 | * created socket, and POSIX does not want network |
| 430 | * errors returned from accept(). |
| 431 | */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 432 | inet_csk_reqsk_queue_drop(sk, req, prev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | goto out; |
| 434 | |
| 435 | case TCP_SYN_SENT: |
| 436 | case TCP_SYN_RECV: /* Cannot happen. |
| 437 | It can f.e. if SYNs crossed. |
| 438 | */ |
| 439 | if (!sock_owned_by_user(sk)) { |
| 440 | TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS); |
| 441 | sk->sk_err = err; |
| 442 | |
| 443 | sk->sk_error_report(sk); |
| 444 | |
| 445 | tcp_done(sk); |
| 446 | } else { |
| 447 | sk->sk_err_soft = err; |
| 448 | } |
| 449 | goto out; |
| 450 | } |
| 451 | |
| 452 | /* If we've already connected we will keep trying |
| 453 | * until we time out, or the user gives up. |
| 454 | * |
| 455 | * rfc1122 4.2.3.9 allows to consider as hard errors |
| 456 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, |
| 457 | * but it is obsoleted by pmtu discovery). |
| 458 | * |
| 459 | * Note, that in modern internet, where routing is unreliable |
| 460 | * and in each dark corner broken firewalls sit, sending random |
| 461 | * errors ordered by their masters even this two messages finally lose |
| 462 | * their original sense (even Linux sends invalid PORT_UNREACHs) |
| 463 | * |
| 464 | * Now we are in compliance with RFCs. |
| 465 | * --ANK (980905) |
| 466 | */ |
| 467 | |
| 468 | inet = inet_sk(sk); |
| 469 | if (!sock_owned_by_user(sk) && inet->recverr) { |
| 470 | sk->sk_err = err; |
| 471 | sk->sk_error_report(sk); |
| 472 | } else { /* Only an error on timeout */ |
| 473 | sk->sk_err_soft = err; |
| 474 | } |
| 475 | |
| 476 | out: |
| 477 | bh_unlock_sock(sk); |
| 478 | sock_put(sk); |
| 479 | } |
| 480 | |
| 481 | /* This routine computes an IPv4 TCP checksum. */ |
Arnaldo Carvalho de Melo | 8292a17 | 2005-12-13 23:15:52 -0800 | [diff] [blame] | 482 | void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | { |
| 484 | struct inet_sock *inet = inet_sk(sk); |
Arnaldo Carvalho de Melo | 8292a17 | 2005-12-13 23:15:52 -0800 | [diff] [blame] | 485 | struct tcphdr *th = skb->h.th; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | |
| 487 | if (skb->ip_summed == CHECKSUM_HW) { |
| 488 | th->check = ~tcp_v4_check(th, len, inet->saddr, inet->daddr, 0); |
| 489 | skb->csum = offsetof(struct tcphdr, check); |
| 490 | } else { |
| 491 | th->check = tcp_v4_check(th, len, inet->saddr, inet->daddr, |
| 492 | csum_partial((char *)th, |
| 493 | th->doff << 2, |
| 494 | skb->csum)); |
| 495 | } |
| 496 | } |
| 497 | |
| 498 | /* |
| 499 | * This routine will send an RST to the other tcp. |
| 500 | * |
| 501 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) |
| 502 | * for reset. |
| 503 | * Answer: if a packet caused RST, it is not for a socket |
| 504 | * existing in our system, if it is matched to a socket, |
| 505 | * it is just duplicate segment or bug in other side's TCP. |
| 506 | * So that we build reply only basing on parameters |
| 507 | * arrived with segment. |
| 508 | * Exception: precedence violation. We do not implement it in any case. |
| 509 | */ |
| 510 | |
| 511 | static void tcp_v4_send_reset(struct sk_buff *skb) |
| 512 | { |
| 513 | struct tcphdr *th = skb->h.th; |
| 514 | struct tcphdr rth; |
| 515 | struct ip_reply_arg arg; |
| 516 | |
| 517 | /* Never send a reset in response to a reset. */ |
| 518 | if (th->rst) |
| 519 | return; |
| 520 | |
| 521 | if (((struct rtable *)skb->dst)->rt_type != RTN_LOCAL) |
| 522 | return; |
| 523 | |
| 524 | /* Swap the send and the receive. */ |
| 525 | memset(&rth, 0, sizeof(struct tcphdr)); |
| 526 | rth.dest = th->source; |
| 527 | rth.source = th->dest; |
| 528 | rth.doff = sizeof(struct tcphdr) / 4; |
| 529 | rth.rst = 1; |
| 530 | |
| 531 | if (th->ack) { |
| 532 | rth.seq = th->ack_seq; |
| 533 | } else { |
| 534 | rth.ack = 1; |
| 535 | rth.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + |
| 536 | skb->len - (th->doff << 2)); |
| 537 | } |
| 538 | |
| 539 | memset(&arg, 0, sizeof arg); |
| 540 | arg.iov[0].iov_base = (unsigned char *)&rth; |
| 541 | arg.iov[0].iov_len = sizeof rth; |
| 542 | arg.csum = csum_tcpudp_nofold(skb->nh.iph->daddr, |
| 543 | skb->nh.iph->saddr, /*XXX*/ |
| 544 | sizeof(struct tcphdr), IPPROTO_TCP, 0); |
| 545 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
| 546 | |
| 547 | ip_send_reply(tcp_socket->sk, skb, &arg, sizeof rth); |
| 548 | |
| 549 | TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); |
| 550 | TCP_INC_STATS_BH(TCP_MIB_OUTRSTS); |
| 551 | } |
| 552 | |
| 553 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states |
| 554 | outside socket context is ugly, certainly. What can I do? |
| 555 | */ |
| 556 | |
| 557 | static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack, |
| 558 | u32 win, u32 ts) |
| 559 | { |
| 560 | struct tcphdr *th = skb->h.th; |
| 561 | struct { |
| 562 | struct tcphdr th; |
| 563 | u32 tsopt[3]; |
| 564 | } rep; |
| 565 | struct ip_reply_arg arg; |
| 566 | |
| 567 | memset(&rep.th, 0, sizeof(struct tcphdr)); |
| 568 | memset(&arg, 0, sizeof arg); |
| 569 | |
| 570 | arg.iov[0].iov_base = (unsigned char *)&rep; |
| 571 | arg.iov[0].iov_len = sizeof(rep.th); |
| 572 | if (ts) { |
| 573 | rep.tsopt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
| 574 | (TCPOPT_TIMESTAMP << 8) | |
| 575 | TCPOLEN_TIMESTAMP); |
| 576 | rep.tsopt[1] = htonl(tcp_time_stamp); |
| 577 | rep.tsopt[2] = htonl(ts); |
| 578 | arg.iov[0].iov_len = sizeof(rep); |
| 579 | } |
| 580 | |
| 581 | /* Swap the send and the receive. */ |
| 582 | rep.th.dest = th->source; |
| 583 | rep.th.source = th->dest; |
| 584 | rep.th.doff = arg.iov[0].iov_len / 4; |
| 585 | rep.th.seq = htonl(seq); |
| 586 | rep.th.ack_seq = htonl(ack); |
| 587 | rep.th.ack = 1; |
| 588 | rep.th.window = htons(win); |
| 589 | |
| 590 | arg.csum = csum_tcpudp_nofold(skb->nh.iph->daddr, |
| 591 | skb->nh.iph->saddr, /*XXX*/ |
| 592 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
| 593 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
| 594 | |
| 595 | ip_send_reply(tcp_socket->sk, skb, &arg, arg.iov[0].iov_len); |
| 596 | |
| 597 | TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); |
| 598 | } |
| 599 | |
| 600 | static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) |
| 601 | { |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 602 | struct inet_timewait_sock *tw = inet_twsk(sk); |
| 603 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 605 | tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
| 606 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, tcptw->tw_ts_recent); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 608 | inet_twsk_put(tw); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | } |
| 610 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 611 | static void tcp_v4_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 613 | tcp_v4_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | req->ts_recent); |
| 615 | } |
| 616 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | /* |
| 618 | * Send a SYN-ACK after having received an ACK. |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 619 | * This still operates on a request_sock only, not on a big |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | * socket. |
| 621 | */ |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 622 | static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | struct dst_entry *dst) |
| 624 | { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 625 | const struct inet_request_sock *ireq = inet_rsk(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | int err = -1; |
| 627 | struct sk_buff * skb; |
| 628 | |
| 629 | /* First, grab a route. */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 630 | if (!dst && (dst = inet_csk_route_req(sk, req)) == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | goto out; |
| 632 | |
| 633 | skb = tcp_make_synack(sk, dst, req); |
| 634 | |
| 635 | if (skb) { |
| 636 | struct tcphdr *th = skb->h.th; |
| 637 | |
| 638 | th->check = tcp_v4_check(th, skb->len, |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 639 | ireq->loc_addr, |
| 640 | ireq->rmt_addr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | csum_partial((char *)th, skb->len, |
| 642 | skb->csum)); |
| 643 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 644 | err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, |
| 645 | ireq->rmt_addr, |
| 646 | ireq->opt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | if (err == NET_XMIT_CN) |
| 648 | err = 0; |
| 649 | } |
| 650 | |
| 651 | out: |
| 652 | dst_release(dst); |
| 653 | return err; |
| 654 | } |
| 655 | |
| 656 | /* |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 657 | * IPv4 request_sock destructor. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | */ |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 659 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 660 | { |
Jesper Juhl | a51482b | 2005-11-08 09:41:34 -0800 | [diff] [blame] | 661 | kfree(inet_rsk(req)->opt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | } |
| 663 | |
Arnaldo Carvalho de Melo | 80e40da | 2006-01-04 01:58:06 -0200 | [diff] [blame] | 664 | #ifdef CONFIG_SYN_COOKIES |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 665 | static void syn_flood_warning(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 666 | { |
| 667 | static unsigned long warntime; |
| 668 | |
| 669 | if (time_after(jiffies, (warntime + HZ * 60))) { |
| 670 | warntime = jiffies; |
| 671 | printk(KERN_INFO |
| 672 | "possible SYN flooding on port %d. Sending cookies.\n", |
| 673 | ntohs(skb->h.th->dest)); |
| 674 | } |
| 675 | } |
Arnaldo Carvalho de Melo | 80e40da | 2006-01-04 01:58:06 -0200 | [diff] [blame] | 676 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | |
| 678 | /* |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 679 | * Save and compile IPv4 options into the request_sock if needed. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | */ |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 681 | static struct ip_options *tcp_v4_save_options(struct sock *sk, |
| 682 | struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | { |
| 684 | struct ip_options *opt = &(IPCB(skb)->opt); |
| 685 | struct ip_options *dopt = NULL; |
| 686 | |
| 687 | if (opt && opt->optlen) { |
| 688 | int opt_size = optlength(opt); |
| 689 | dopt = kmalloc(opt_size, GFP_ATOMIC); |
| 690 | if (dopt) { |
| 691 | if (ip_options_echo(dopt, skb)) { |
| 692 | kfree(dopt); |
| 693 | dopt = NULL; |
| 694 | } |
| 695 | } |
| 696 | } |
| 697 | return dopt; |
| 698 | } |
| 699 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 700 | struct request_sock_ops tcp_request_sock_ops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | .family = PF_INET, |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 702 | .obj_size = sizeof(struct tcp_request_sock), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | .rtx_syn_ack = tcp_v4_send_synack, |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 704 | .send_ack = tcp_v4_reqsk_send_ack, |
| 705 | .destructor = tcp_v4_reqsk_destructor, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | .send_reset = tcp_v4_send_reset, |
| 707 | }; |
| 708 | |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 709 | static struct timewait_sock_ops tcp_timewait_sock_ops = { |
| 710 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), |
| 711 | .twsk_unique = tcp_twsk_unique, |
| 712 | }; |
| 713 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 714 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
| 715 | { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 716 | struct inet_request_sock *ireq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | struct tcp_options_received tmp_opt; |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 718 | struct request_sock *req; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | __u32 saddr = skb->nh.iph->saddr; |
| 720 | __u32 daddr = skb->nh.iph->daddr; |
| 721 | __u32 isn = TCP_SKB_CB(skb)->when; |
| 722 | struct dst_entry *dst = NULL; |
| 723 | #ifdef CONFIG_SYN_COOKIES |
| 724 | int want_cookie = 0; |
| 725 | #else |
| 726 | #define want_cookie 0 /* Argh, why doesn't gcc optimize this :( */ |
| 727 | #endif |
| 728 | |
| 729 | /* Never answer to SYNs send to broadcast or multicast */ |
| 730 | if (((struct rtable *)skb->dst)->rt_flags & |
| 731 | (RTCF_BROADCAST | RTCF_MULTICAST)) |
| 732 | goto drop; |
| 733 | |
| 734 | /* TW buckets are converted to open requests without |
| 735 | * limitations, they conserve resources and peer is |
| 736 | * evidently real one. |
| 737 | */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 738 | if (inet_csk_reqsk_queue_is_full(sk) && !isn) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | #ifdef CONFIG_SYN_COOKIES |
| 740 | if (sysctl_tcp_syncookies) { |
| 741 | want_cookie = 1; |
| 742 | } else |
| 743 | #endif |
| 744 | goto drop; |
| 745 | } |
| 746 | |
| 747 | /* Accept backlog is full. If we have already queued enough |
| 748 | * of warm entries in syn queue, drop request. It is better than |
| 749 | * clogging syn queue with openreqs with exponentially increasing |
| 750 | * timeout. |
| 751 | */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 752 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | goto drop; |
| 754 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 755 | req = reqsk_alloc(&tcp_request_sock_ops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | if (!req) |
| 757 | goto drop; |
| 758 | |
| 759 | tcp_clear_options(&tmp_opt); |
| 760 | tmp_opt.mss_clamp = 536; |
| 761 | tmp_opt.user_mss = tcp_sk(sk)->rx_opt.user_mss; |
| 762 | |
| 763 | tcp_parse_options(skb, &tmp_opt, 0); |
| 764 | |
| 765 | if (want_cookie) { |
| 766 | tcp_clear_options(&tmp_opt); |
| 767 | tmp_opt.saw_tstamp = 0; |
| 768 | } |
| 769 | |
| 770 | if (tmp_opt.saw_tstamp && !tmp_opt.rcv_tsval) { |
| 771 | /* Some OSes (unknown ones, but I see them on web server, which |
| 772 | * contains information interesting only for windows' |
| 773 | * users) do not send their stamp in SYN. It is easy case. |
| 774 | * We simply do not advertise TS support. |
| 775 | */ |
| 776 | tmp_opt.saw_tstamp = 0; |
| 777 | tmp_opt.tstamp_ok = 0; |
| 778 | } |
| 779 | tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; |
| 780 | |
| 781 | tcp_openreq_init(req, &tmp_opt, skb); |
| 782 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 783 | ireq = inet_rsk(req); |
| 784 | ireq->loc_addr = daddr; |
| 785 | ireq->rmt_addr = saddr; |
| 786 | ireq->opt = tcp_v4_save_options(sk, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 787 | if (!want_cookie) |
| 788 | TCP_ECN_create_request(req, skb->h.th); |
| 789 | |
| 790 | if (want_cookie) { |
| 791 | #ifdef CONFIG_SYN_COOKIES |
| 792 | syn_flood_warning(skb); |
| 793 | #endif |
| 794 | isn = cookie_v4_init_sequence(sk, skb, &req->mss); |
| 795 | } else if (!isn) { |
| 796 | struct inet_peer *peer = NULL; |
| 797 | |
| 798 | /* VJ's idea. We save last timestamp seen |
| 799 | * from the destination in peer table, when entering |
| 800 | * state TIME-WAIT, and check against it before |
| 801 | * accepting new connection request. |
| 802 | * |
| 803 | * If "isn" is not zero, this request hit alive |
| 804 | * timewait bucket, so that all the necessary checks |
| 805 | * are made in the function processing timewait state. |
| 806 | */ |
| 807 | if (tmp_opt.saw_tstamp && |
Arnaldo Carvalho de Melo | 295ff7e | 2005-08-09 20:44:40 -0700 | [diff] [blame] | 808 | tcp_death_row.sysctl_tw_recycle && |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 809 | (dst = inet_csk_route_req(sk, req)) != NULL && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | (peer = rt_get_peer((struct rtable *)dst)) != NULL && |
| 811 | peer->v4daddr == saddr) { |
| 812 | if (xtime.tv_sec < peer->tcp_ts_stamp + TCP_PAWS_MSL && |
| 813 | (s32)(peer->tcp_ts - req->ts_recent) > |
| 814 | TCP_PAWS_WINDOW) { |
| 815 | NET_INC_STATS_BH(LINUX_MIB_PAWSPASSIVEREJECTED); |
| 816 | dst_release(dst); |
| 817 | goto drop_and_free; |
| 818 | } |
| 819 | } |
| 820 | /* Kill the following clause, if you dislike this way. */ |
| 821 | else if (!sysctl_tcp_syncookies && |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 822 | (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) < |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | (sysctl_max_syn_backlog >> 2)) && |
| 824 | (!peer || !peer->tcp_ts_stamp) && |
| 825 | (!dst || !dst_metric(dst, RTAX_RTT))) { |
| 826 | /* Without syncookies last quarter of |
| 827 | * backlog is filled with destinations, |
| 828 | * proven to be alive. |
| 829 | * It means that we continue to communicate |
| 830 | * to destinations, already remembered |
| 831 | * to the moment of synflood. |
| 832 | */ |
Patrick McHardy | 64ce207 | 2005-08-09 20:50:53 -0700 | [diff] [blame] | 833 | LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open " |
| 834 | "request from %u.%u.%u.%u/%u\n", |
| 835 | NIPQUAD(saddr), |
| 836 | ntohs(skb->h.th->source)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | dst_release(dst); |
| 838 | goto drop_and_free; |
| 839 | } |
| 840 | |
| 841 | isn = tcp_v4_init_sequence(sk, skb); |
| 842 | } |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 843 | tcp_rsk(req)->snt_isn = isn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 844 | |
| 845 | if (tcp_v4_send_synack(sk, req, dst)) |
| 846 | goto drop_and_free; |
| 847 | |
| 848 | if (want_cookie) { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 849 | reqsk_free(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 850 | } else { |
Arnaldo Carvalho de Melo | 3f421ba | 2005-08-09 20:11:08 -0700 | [diff] [blame] | 851 | inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | } |
| 853 | return 0; |
| 854 | |
| 855 | drop_and_free: |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 856 | reqsk_free(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 857 | drop: |
| 858 | TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS); |
| 859 | return 0; |
| 860 | } |
| 861 | |
| 862 | |
| 863 | /* |
| 864 | * The three way handshake has completed - we got a valid synack - |
| 865 | * now create the new socket. |
| 866 | */ |
| 867 | struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 868 | struct request_sock *req, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 869 | struct dst_entry *dst) |
| 870 | { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 871 | struct inet_request_sock *ireq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 872 | struct inet_sock *newinet; |
| 873 | struct tcp_sock *newtp; |
| 874 | struct sock *newsk; |
| 875 | |
| 876 | if (sk_acceptq_is_full(sk)) |
| 877 | goto exit_overflow; |
| 878 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 879 | if (!dst && (dst = inet_csk_route_req(sk, req)) == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | goto exit; |
| 881 | |
| 882 | newsk = tcp_create_openreq_child(sk, req, skb); |
| 883 | if (!newsk) |
| 884 | goto exit; |
| 885 | |
Arnaldo Carvalho de Melo | 6cbb0df | 2005-08-09 19:49:02 -0700 | [diff] [blame] | 886 | sk_setup_caps(newsk, dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 887 | |
| 888 | newtp = tcp_sk(newsk); |
| 889 | newinet = inet_sk(newsk); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 890 | ireq = inet_rsk(req); |
| 891 | newinet->daddr = ireq->rmt_addr; |
| 892 | newinet->rcv_saddr = ireq->loc_addr; |
| 893 | newinet->saddr = ireq->loc_addr; |
| 894 | newinet->opt = ireq->opt; |
| 895 | ireq->opt = NULL; |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 896 | newinet->mc_index = inet_iif(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | newinet->mc_ttl = skb->nh.iph->ttl; |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 898 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | if (newinet->opt) |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 900 | inet_csk(newsk)->icsk_ext_hdr_len = newinet->opt->optlen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 901 | newinet->id = newtp->write_seq ^ jiffies; |
| 902 | |
John Heffner | 5d424d5 | 2006-03-20 17:53:41 -0800 | [diff] [blame] | 903 | tcp_mtup_init(newsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 904 | tcp_sync_mss(newsk, dst_mtu(dst)); |
| 905 | newtp->advmss = dst_metric(dst, RTAX_ADVMSS); |
| 906 | tcp_initialize_rcv_mss(newsk); |
| 907 | |
Arnaldo Carvalho de Melo | f3f05f7 | 2005-08-09 20:08:09 -0700 | [diff] [blame] | 908 | __inet_hash(&tcp_hashinfo, newsk, 0); |
Arnaldo Carvalho de Melo | 2d8c4ce | 2005-08-09 20:07:13 -0700 | [diff] [blame] | 909 | __inet_inherit_port(&tcp_hashinfo, sk, newsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 910 | |
| 911 | return newsk; |
| 912 | |
| 913 | exit_overflow: |
| 914 | NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); |
| 915 | exit: |
| 916 | NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); |
| 917 | dst_release(dst); |
| 918 | return NULL; |
| 919 | } |
| 920 | |
| 921 | static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) |
| 922 | { |
| 923 | struct tcphdr *th = skb->h.th; |
| 924 | struct iphdr *iph = skb->nh.iph; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 925 | struct sock *nsk; |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 926 | struct request_sock **prev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 927 | /* Find possible connection requests. */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 928 | struct request_sock *req = inet_csk_search_req(sk, &prev, th->source, |
| 929 | iph->saddr, iph->daddr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | if (req) |
| 931 | return tcp_check_req(sk, skb, req, prev); |
| 932 | |
Arnaldo Carvalho de Melo | e48c414 | 2005-08-09 20:09:46 -0700 | [diff] [blame] | 933 | nsk = __inet_lookup_established(&tcp_hashinfo, skb->nh.iph->saddr, |
| 934 | th->source, skb->nh.iph->daddr, |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 935 | ntohs(th->dest), inet_iif(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | |
| 937 | if (nsk) { |
| 938 | if (nsk->sk_state != TCP_TIME_WAIT) { |
| 939 | bh_lock_sock(nsk); |
| 940 | return nsk; |
| 941 | } |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 942 | inet_twsk_put((struct inet_timewait_sock *)nsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 943 | return NULL; |
| 944 | } |
| 945 | |
| 946 | #ifdef CONFIG_SYN_COOKIES |
| 947 | if (!th->rst && !th->syn && th->ack) |
| 948 | sk = cookie_v4_check(sk, skb, &(IPCB(skb)->opt)); |
| 949 | #endif |
| 950 | return sk; |
| 951 | } |
| 952 | |
| 953 | static int tcp_v4_checksum_init(struct sk_buff *skb) |
| 954 | { |
| 955 | if (skb->ip_summed == CHECKSUM_HW) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 956 | if (!tcp_v4_check(skb->h.th, skb->len, skb->nh.iph->saddr, |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 957 | skb->nh.iph->daddr, skb->csum)) { |
| 958 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 959 | return 0; |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 960 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | } |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 962 | |
| 963 | skb->csum = csum_tcpudp_nofold(skb->nh.iph->saddr, skb->nh.iph->daddr, |
| 964 | skb->len, IPPROTO_TCP, 0); |
| 965 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | if (skb->len <= 76) { |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 967 | return __skb_checksum_complete(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 968 | } |
| 969 | return 0; |
| 970 | } |
| 971 | |
| 972 | |
| 973 | /* The socket must have it's spinlock held when we get |
| 974 | * here. |
| 975 | * |
| 976 | * We have a potential double-lock case here, so even when |
| 977 | * doing backlog processing we use the BH locking scheme. |
| 978 | * This is because we cannot sleep with the original spinlock |
| 979 | * held. |
| 980 | */ |
| 981 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) |
| 982 | { |
| 983 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
| 984 | TCP_CHECK_TIMER(sk); |
| 985 | if (tcp_rcv_established(sk, skb, skb->h.th, skb->len)) |
| 986 | goto reset; |
| 987 | TCP_CHECK_TIMER(sk); |
| 988 | return 0; |
| 989 | } |
| 990 | |
| 991 | if (skb->len < (skb->h.th->doff << 2) || tcp_checksum_complete(skb)) |
| 992 | goto csum_err; |
| 993 | |
| 994 | if (sk->sk_state == TCP_LISTEN) { |
| 995 | struct sock *nsk = tcp_v4_hnd_req(sk, skb); |
| 996 | if (!nsk) |
| 997 | goto discard; |
| 998 | |
| 999 | if (nsk != sk) { |
| 1000 | if (tcp_child_process(sk, nsk, skb)) |
| 1001 | goto reset; |
| 1002 | return 0; |
| 1003 | } |
| 1004 | } |
| 1005 | |
| 1006 | TCP_CHECK_TIMER(sk); |
| 1007 | if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len)) |
| 1008 | goto reset; |
| 1009 | TCP_CHECK_TIMER(sk); |
| 1010 | return 0; |
| 1011 | |
| 1012 | reset: |
| 1013 | tcp_v4_send_reset(skb); |
| 1014 | discard: |
| 1015 | kfree_skb(skb); |
| 1016 | /* Be careful here. If this function gets more complicated and |
| 1017 | * gcc suffers from register pressure on the x86, sk (in %ebx) |
| 1018 | * might be destroyed here. This current version compiles correctly, |
| 1019 | * but you have been warned. |
| 1020 | */ |
| 1021 | return 0; |
| 1022 | |
| 1023 | csum_err: |
| 1024 | TCP_INC_STATS_BH(TCP_MIB_INERRS); |
| 1025 | goto discard; |
| 1026 | } |
| 1027 | |
| 1028 | /* |
| 1029 | * From tcp_input.c |
| 1030 | */ |
| 1031 | |
| 1032 | int tcp_v4_rcv(struct sk_buff *skb) |
| 1033 | { |
| 1034 | struct tcphdr *th; |
| 1035 | struct sock *sk; |
| 1036 | int ret; |
| 1037 | |
| 1038 | if (skb->pkt_type != PACKET_HOST) |
| 1039 | goto discard_it; |
| 1040 | |
| 1041 | /* Count it even if it's bad */ |
| 1042 | TCP_INC_STATS_BH(TCP_MIB_INSEGS); |
| 1043 | |
| 1044 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) |
| 1045 | goto discard_it; |
| 1046 | |
| 1047 | th = skb->h.th; |
| 1048 | |
| 1049 | if (th->doff < sizeof(struct tcphdr) / 4) |
| 1050 | goto bad_packet; |
| 1051 | if (!pskb_may_pull(skb, th->doff * 4)) |
| 1052 | goto discard_it; |
| 1053 | |
| 1054 | /* An explanation is required here, I think. |
| 1055 | * Packet length and doff are validated by header prediction, |
Stephen Hemminger | caa20d9a | 2005-11-10 17:13:47 -0800 | [diff] [blame] | 1056 | * provided case of th->doff==0 is eliminated. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1057 | * So, we defer the checks. */ |
| 1058 | if ((skb->ip_summed != CHECKSUM_UNNECESSARY && |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 1059 | tcp_v4_checksum_init(skb))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1060 | goto bad_packet; |
| 1061 | |
| 1062 | th = skb->h.th; |
| 1063 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); |
| 1064 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + |
| 1065 | skb->len - th->doff * 4); |
| 1066 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); |
| 1067 | TCP_SKB_CB(skb)->when = 0; |
| 1068 | TCP_SKB_CB(skb)->flags = skb->nh.iph->tos; |
| 1069 | TCP_SKB_CB(skb)->sacked = 0; |
| 1070 | |
Arnaldo Carvalho de Melo | e48c414 | 2005-08-09 20:09:46 -0700 | [diff] [blame] | 1071 | sk = __inet_lookup(&tcp_hashinfo, skb->nh.iph->saddr, th->source, |
| 1072 | skb->nh.iph->daddr, ntohs(th->dest), |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1073 | inet_iif(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1074 | |
| 1075 | if (!sk) |
| 1076 | goto no_tcp_socket; |
| 1077 | |
| 1078 | process: |
| 1079 | if (sk->sk_state == TCP_TIME_WAIT) |
| 1080 | goto do_time_wait; |
| 1081 | |
| 1082 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
| 1083 | goto discard_and_relse; |
Patrick McHardy | b59c270 | 2006-01-06 23:06:10 -0800 | [diff] [blame] | 1084 | nf_reset(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1085 | |
| 1086 | if (sk_filter(sk, skb, 0)) |
| 1087 | goto discard_and_relse; |
| 1088 | |
| 1089 | skb->dev = NULL; |
| 1090 | |
| 1091 | bh_lock_sock(sk); |
| 1092 | ret = 0; |
| 1093 | if (!sock_owned_by_user(sk)) { |
| 1094 | if (!tcp_prequeue(sk, skb)) |
| 1095 | ret = tcp_v4_do_rcv(sk, skb); |
| 1096 | } else |
| 1097 | sk_add_backlog(sk, skb); |
| 1098 | bh_unlock_sock(sk); |
| 1099 | |
| 1100 | sock_put(sk); |
| 1101 | |
| 1102 | return ret; |
| 1103 | |
| 1104 | no_tcp_socket: |
| 1105 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| 1106 | goto discard_it; |
| 1107 | |
| 1108 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { |
| 1109 | bad_packet: |
| 1110 | TCP_INC_STATS_BH(TCP_MIB_INERRS); |
| 1111 | } else { |
| 1112 | tcp_v4_send_reset(skb); |
| 1113 | } |
| 1114 | |
| 1115 | discard_it: |
| 1116 | /* Discard frame. */ |
| 1117 | kfree_skb(skb); |
| 1118 | return 0; |
| 1119 | |
| 1120 | discard_and_relse: |
| 1121 | sock_put(sk); |
| 1122 | goto discard_it; |
| 1123 | |
| 1124 | do_time_wait: |
| 1125 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1126 | inet_twsk_put((struct inet_timewait_sock *) sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1127 | goto discard_it; |
| 1128 | } |
| 1129 | |
| 1130 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { |
| 1131 | TCP_INC_STATS_BH(TCP_MIB_INERRS); |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1132 | inet_twsk_put((struct inet_timewait_sock *) sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | goto discard_it; |
| 1134 | } |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1135 | switch (tcp_timewait_state_process((struct inet_timewait_sock *)sk, |
| 1136 | skb, th)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1137 | case TCP_TW_SYN: { |
Arnaldo Carvalho de Melo | 33b6223 | 2005-08-09 20:09:06 -0700 | [diff] [blame] | 1138 | struct sock *sk2 = inet_lookup_listener(&tcp_hashinfo, |
| 1139 | skb->nh.iph->daddr, |
| 1140 | ntohs(th->dest), |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1141 | inet_iif(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1142 | if (sk2) { |
Arnaldo Carvalho de Melo | 295ff7e | 2005-08-09 20:44:40 -0700 | [diff] [blame] | 1143 | inet_twsk_deschedule((struct inet_timewait_sock *)sk, |
| 1144 | &tcp_death_row); |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1145 | inet_twsk_put((struct inet_timewait_sock *)sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | sk = sk2; |
| 1147 | goto process; |
| 1148 | } |
| 1149 | /* Fall through to ACK */ |
| 1150 | } |
| 1151 | case TCP_TW_ACK: |
| 1152 | tcp_v4_timewait_ack(sk, skb); |
| 1153 | break; |
| 1154 | case TCP_TW_RST: |
| 1155 | goto no_tcp_socket; |
| 1156 | case TCP_TW_SUCCESS:; |
| 1157 | } |
| 1158 | goto discard_it; |
| 1159 | } |
| 1160 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1161 | /* VJ's idea. Save last timestamp seen from this destination |
| 1162 | * and hold it at least for normal timewait interval to use for duplicate |
| 1163 | * segment detection in subsequent connections, before they enter synchronized |
| 1164 | * state. |
| 1165 | */ |
| 1166 | |
| 1167 | int tcp_v4_remember_stamp(struct sock *sk) |
| 1168 | { |
| 1169 | struct inet_sock *inet = inet_sk(sk); |
| 1170 | struct tcp_sock *tp = tcp_sk(sk); |
| 1171 | struct rtable *rt = (struct rtable *)__sk_dst_get(sk); |
| 1172 | struct inet_peer *peer = NULL; |
| 1173 | int release_it = 0; |
| 1174 | |
| 1175 | if (!rt || rt->rt_dst != inet->daddr) { |
| 1176 | peer = inet_getpeer(inet->daddr, 1); |
| 1177 | release_it = 1; |
| 1178 | } else { |
| 1179 | if (!rt->peer) |
| 1180 | rt_bind_peer(rt, 1); |
| 1181 | peer = rt->peer; |
| 1182 | } |
| 1183 | |
| 1184 | if (peer) { |
| 1185 | if ((s32)(peer->tcp_ts - tp->rx_opt.ts_recent) <= 0 || |
| 1186 | (peer->tcp_ts_stamp + TCP_PAWS_MSL < xtime.tv_sec && |
| 1187 | peer->tcp_ts_stamp <= tp->rx_opt.ts_recent_stamp)) { |
| 1188 | peer->tcp_ts_stamp = tp->rx_opt.ts_recent_stamp; |
| 1189 | peer->tcp_ts = tp->rx_opt.ts_recent; |
| 1190 | } |
| 1191 | if (release_it) |
| 1192 | inet_putpeer(peer); |
| 1193 | return 1; |
| 1194 | } |
| 1195 | |
| 1196 | return 0; |
| 1197 | } |
| 1198 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1199 | int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1200 | { |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1201 | struct inet_peer *peer = inet_getpeer(tw->tw_daddr, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1202 | |
| 1203 | if (peer) { |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1204 | const struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); |
| 1205 | |
| 1206 | if ((s32)(peer->tcp_ts - tcptw->tw_ts_recent) <= 0 || |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1207 | (peer->tcp_ts_stamp + TCP_PAWS_MSL < xtime.tv_sec && |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1208 | peer->tcp_ts_stamp <= tcptw->tw_ts_recent_stamp)) { |
| 1209 | peer->tcp_ts_stamp = tcptw->tw_ts_recent_stamp; |
| 1210 | peer->tcp_ts = tcptw->tw_ts_recent; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1211 | } |
| 1212 | inet_putpeer(peer); |
| 1213 | return 1; |
| 1214 | } |
| 1215 | |
| 1216 | return 0; |
| 1217 | } |
| 1218 | |
Arnaldo Carvalho de Melo | 8292a17 | 2005-12-13 23:15:52 -0800 | [diff] [blame] | 1219 | struct inet_connection_sock_af_ops ipv4_specific = { |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 1220 | .queue_xmit = ip_queue_xmit, |
| 1221 | .send_check = tcp_v4_send_check, |
| 1222 | .rebuild_header = inet_sk_rebuild_header, |
| 1223 | .conn_request = tcp_v4_conn_request, |
| 1224 | .syn_recv_sock = tcp_v4_syn_recv_sock, |
| 1225 | .remember_stamp = tcp_v4_remember_stamp, |
| 1226 | .net_header_len = sizeof(struct iphdr), |
| 1227 | .setsockopt = ip_setsockopt, |
| 1228 | .getsockopt = ip_getsockopt, |
| 1229 | .addr2sockaddr = inet_csk_addr2sockaddr, |
| 1230 | .sockaddr_len = sizeof(struct sockaddr_in), |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 1231 | #ifdef CONFIG_COMPAT |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 1232 | .compat_setsockopt = compat_ip_setsockopt, |
| 1233 | .compat_getsockopt = compat_ip_getsockopt, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 1234 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1235 | }; |
| 1236 | |
| 1237 | /* NOTE: A lot of things set to zero explicitly by call to |
| 1238 | * sk_alloc() so need not be done here. |
| 1239 | */ |
| 1240 | static int tcp_v4_init_sock(struct sock *sk) |
| 1241 | { |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 1242 | struct inet_connection_sock *icsk = inet_csk(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1243 | struct tcp_sock *tp = tcp_sk(sk); |
| 1244 | |
| 1245 | skb_queue_head_init(&tp->out_of_order_queue); |
| 1246 | tcp_init_xmit_timers(sk); |
| 1247 | tcp_prequeue_init(tp); |
| 1248 | |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 1249 | icsk->icsk_rto = TCP_TIMEOUT_INIT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1250 | tp->mdev = TCP_TIMEOUT_INIT; |
| 1251 | |
| 1252 | /* So many TCP implementations out there (incorrectly) count the |
| 1253 | * initial SYN frame in their delayed-ACK and congestion control |
| 1254 | * algorithms that we must have the following bandaid to talk |
| 1255 | * efficiently to them. -DaveM |
| 1256 | */ |
| 1257 | tp->snd_cwnd = 2; |
| 1258 | |
| 1259 | /* See draft-stevens-tcpca-spec-01 for discussion of the |
| 1260 | * initialization of these values. |
| 1261 | */ |
| 1262 | tp->snd_ssthresh = 0x7fffffff; /* Infinity */ |
| 1263 | tp->snd_cwnd_clamp = ~0; |
David S. Miller | c1b4a7e | 2005-07-05 15:24:38 -0700 | [diff] [blame] | 1264 | tp->mss_cache = 536; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1265 | |
| 1266 | tp->reordering = sysctl_tcp_reordering; |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 1267 | icsk->icsk_ca_ops = &tcp_init_congestion_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1268 | |
| 1269 | sk->sk_state = TCP_CLOSE; |
| 1270 | |
| 1271 | sk->sk_write_space = sk_stream_write_space; |
| 1272 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); |
| 1273 | |
Arnaldo Carvalho de Melo | 8292a17 | 2005-12-13 23:15:52 -0800 | [diff] [blame] | 1274 | icsk->icsk_af_ops = &ipv4_specific; |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 1275 | icsk->icsk_sync_mss = tcp_sync_mss; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1276 | |
| 1277 | sk->sk_sndbuf = sysctl_tcp_wmem[1]; |
| 1278 | sk->sk_rcvbuf = sysctl_tcp_rmem[1]; |
| 1279 | |
| 1280 | atomic_inc(&tcp_sockets_allocated); |
| 1281 | |
| 1282 | return 0; |
| 1283 | } |
| 1284 | |
| 1285 | int tcp_v4_destroy_sock(struct sock *sk) |
| 1286 | { |
| 1287 | struct tcp_sock *tp = tcp_sk(sk); |
| 1288 | |
| 1289 | tcp_clear_xmit_timers(sk); |
| 1290 | |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 1291 | tcp_cleanup_congestion_control(sk); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 1292 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1293 | /* Cleanup up the write buffer. */ |
| 1294 | sk_stream_writequeue_purge(sk); |
| 1295 | |
| 1296 | /* Cleans up our, hopefully empty, out_of_order_queue. */ |
| 1297 | __skb_queue_purge(&tp->out_of_order_queue); |
| 1298 | |
| 1299 | /* Clean prequeue, it must be empty really */ |
| 1300 | __skb_queue_purge(&tp->ucopy.prequeue); |
| 1301 | |
| 1302 | /* Clean up a referenced TCP bind bucket. */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1303 | if (inet_csk(sk)->icsk_bind_hash) |
Arnaldo Carvalho de Melo | 2d8c4ce | 2005-08-09 20:07:13 -0700 | [diff] [blame] | 1304 | inet_put_port(&tcp_hashinfo, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1305 | |
| 1306 | /* |
| 1307 | * If sendmsg cached page exists, toss it. |
| 1308 | */ |
| 1309 | if (sk->sk_sndmsg_page) { |
| 1310 | __free_page(sk->sk_sndmsg_page); |
| 1311 | sk->sk_sndmsg_page = NULL; |
| 1312 | } |
| 1313 | |
| 1314 | atomic_dec(&tcp_sockets_allocated); |
| 1315 | |
| 1316 | return 0; |
| 1317 | } |
| 1318 | |
| 1319 | EXPORT_SYMBOL(tcp_v4_destroy_sock); |
| 1320 | |
| 1321 | #ifdef CONFIG_PROC_FS |
| 1322 | /* Proc filesystem TCP sock list dumping. */ |
| 1323 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1324 | static inline struct inet_timewait_sock *tw_head(struct hlist_head *head) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1325 | { |
| 1326 | return hlist_empty(head) ? NULL : |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1327 | list_entry(head->first, struct inet_timewait_sock, tw_node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1328 | } |
| 1329 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1330 | static inline struct inet_timewait_sock *tw_next(struct inet_timewait_sock *tw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1331 | { |
| 1332 | return tw->tw_node.next ? |
| 1333 | hlist_entry(tw->tw_node.next, typeof(*tw), tw_node) : NULL; |
| 1334 | } |
| 1335 | |
| 1336 | static void *listening_get_next(struct seq_file *seq, void *cur) |
| 1337 | { |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1338 | struct inet_connection_sock *icsk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1339 | struct hlist_node *node; |
| 1340 | struct sock *sk = cur; |
| 1341 | struct tcp_iter_state* st = seq->private; |
| 1342 | |
| 1343 | if (!sk) { |
| 1344 | st->bucket = 0; |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1345 | sk = sk_head(&tcp_hashinfo.listening_hash[0]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1346 | goto get_sk; |
| 1347 | } |
| 1348 | |
| 1349 | ++st->num; |
| 1350 | |
| 1351 | if (st->state == TCP_SEQ_STATE_OPENREQ) { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 1352 | struct request_sock *req = cur; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1353 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1354 | icsk = inet_csk(st->syn_wait_sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1355 | req = req->dl_next; |
| 1356 | while (1) { |
| 1357 | while (req) { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 1358 | if (req->rsk_ops->family == st->family) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1359 | cur = req; |
| 1360 | goto out; |
| 1361 | } |
| 1362 | req = req->dl_next; |
| 1363 | } |
| 1364 | if (++st->sbucket >= TCP_SYNQ_HSIZE) |
| 1365 | break; |
| 1366 | get_req: |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1367 | req = icsk->icsk_accept_queue.listen_opt->syn_table[st->sbucket]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1368 | } |
| 1369 | sk = sk_next(st->syn_wait_sk); |
| 1370 | st->state = TCP_SEQ_STATE_LISTENING; |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1371 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1372 | } else { |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1373 | icsk = inet_csk(sk); |
| 1374 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
| 1375 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1376 | goto start_req; |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1377 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1378 | sk = sk_next(sk); |
| 1379 | } |
| 1380 | get_sk: |
| 1381 | sk_for_each_from(sk, node) { |
| 1382 | if (sk->sk_family == st->family) { |
| 1383 | cur = sk; |
| 1384 | goto out; |
| 1385 | } |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1386 | icsk = inet_csk(sk); |
| 1387 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
| 1388 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1389 | start_req: |
| 1390 | st->uid = sock_i_uid(sk); |
| 1391 | st->syn_wait_sk = sk; |
| 1392 | st->state = TCP_SEQ_STATE_OPENREQ; |
| 1393 | st->sbucket = 0; |
| 1394 | goto get_req; |
| 1395 | } |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1396 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1397 | } |
Arnaldo Carvalho de Melo | 0f7ff92 | 2005-08-09 19:59:44 -0700 | [diff] [blame] | 1398 | if (++st->bucket < INET_LHTABLE_SIZE) { |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1399 | sk = sk_head(&tcp_hashinfo.listening_hash[st->bucket]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1400 | goto get_sk; |
| 1401 | } |
| 1402 | cur = NULL; |
| 1403 | out: |
| 1404 | return cur; |
| 1405 | } |
| 1406 | |
| 1407 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) |
| 1408 | { |
| 1409 | void *rc = listening_get_next(seq, NULL); |
| 1410 | |
| 1411 | while (rc && *pos) { |
| 1412 | rc = listening_get_next(seq, rc); |
| 1413 | --*pos; |
| 1414 | } |
| 1415 | return rc; |
| 1416 | } |
| 1417 | |
| 1418 | static void *established_get_first(struct seq_file *seq) |
| 1419 | { |
| 1420 | struct tcp_iter_state* st = seq->private; |
| 1421 | void *rc = NULL; |
| 1422 | |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1423 | for (st->bucket = 0; st->bucket < tcp_hashinfo.ehash_size; ++st->bucket) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1424 | struct sock *sk; |
| 1425 | struct hlist_node *node; |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1426 | struct inet_timewait_sock *tw; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1427 | |
| 1428 | /* We can reschedule _before_ having picked the target: */ |
| 1429 | cond_resched_softirq(); |
| 1430 | |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1431 | read_lock(&tcp_hashinfo.ehash[st->bucket].lock); |
| 1432 | sk_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1433 | if (sk->sk_family != st->family) { |
| 1434 | continue; |
| 1435 | } |
| 1436 | rc = sk; |
| 1437 | goto out; |
| 1438 | } |
| 1439 | st->state = TCP_SEQ_STATE_TIME_WAIT; |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1440 | inet_twsk_for_each(tw, node, |
| 1441 | &tcp_hashinfo.ehash[st->bucket + tcp_hashinfo.ehash_size].chain) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1442 | if (tw->tw_family != st->family) { |
| 1443 | continue; |
| 1444 | } |
| 1445 | rc = tw; |
| 1446 | goto out; |
| 1447 | } |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1448 | read_unlock(&tcp_hashinfo.ehash[st->bucket].lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1449 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
| 1450 | } |
| 1451 | out: |
| 1452 | return rc; |
| 1453 | } |
| 1454 | |
| 1455 | static void *established_get_next(struct seq_file *seq, void *cur) |
| 1456 | { |
| 1457 | struct sock *sk = cur; |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1458 | struct inet_timewait_sock *tw; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1459 | struct hlist_node *node; |
| 1460 | struct tcp_iter_state* st = seq->private; |
| 1461 | |
| 1462 | ++st->num; |
| 1463 | |
| 1464 | if (st->state == TCP_SEQ_STATE_TIME_WAIT) { |
| 1465 | tw = cur; |
| 1466 | tw = tw_next(tw); |
| 1467 | get_tw: |
| 1468 | while (tw && tw->tw_family != st->family) { |
| 1469 | tw = tw_next(tw); |
| 1470 | } |
| 1471 | if (tw) { |
| 1472 | cur = tw; |
| 1473 | goto out; |
| 1474 | } |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1475 | read_unlock(&tcp_hashinfo.ehash[st->bucket].lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1476 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
| 1477 | |
| 1478 | /* We can reschedule between buckets: */ |
| 1479 | cond_resched_softirq(); |
| 1480 | |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1481 | if (++st->bucket < tcp_hashinfo.ehash_size) { |
| 1482 | read_lock(&tcp_hashinfo.ehash[st->bucket].lock); |
| 1483 | sk = sk_head(&tcp_hashinfo.ehash[st->bucket].chain); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1484 | } else { |
| 1485 | cur = NULL; |
| 1486 | goto out; |
| 1487 | } |
| 1488 | } else |
| 1489 | sk = sk_next(sk); |
| 1490 | |
| 1491 | sk_for_each_from(sk, node) { |
| 1492 | if (sk->sk_family == st->family) |
| 1493 | goto found; |
| 1494 | } |
| 1495 | |
| 1496 | st->state = TCP_SEQ_STATE_TIME_WAIT; |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1497 | tw = tw_head(&tcp_hashinfo.ehash[st->bucket + tcp_hashinfo.ehash_size].chain); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1498 | goto get_tw; |
| 1499 | found: |
| 1500 | cur = sk; |
| 1501 | out: |
| 1502 | return cur; |
| 1503 | } |
| 1504 | |
| 1505 | static void *established_get_idx(struct seq_file *seq, loff_t pos) |
| 1506 | { |
| 1507 | void *rc = established_get_first(seq); |
| 1508 | |
| 1509 | while (rc && pos) { |
| 1510 | rc = established_get_next(seq, rc); |
| 1511 | --pos; |
| 1512 | } |
| 1513 | return rc; |
| 1514 | } |
| 1515 | |
| 1516 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) |
| 1517 | { |
| 1518 | void *rc; |
| 1519 | struct tcp_iter_state* st = seq->private; |
| 1520 | |
Arnaldo Carvalho de Melo | f3f05f7 | 2005-08-09 20:08:09 -0700 | [diff] [blame] | 1521 | inet_listen_lock(&tcp_hashinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1522 | st->state = TCP_SEQ_STATE_LISTENING; |
| 1523 | rc = listening_get_idx(seq, &pos); |
| 1524 | |
| 1525 | if (!rc) { |
Arnaldo Carvalho de Melo | f3f05f7 | 2005-08-09 20:08:09 -0700 | [diff] [blame] | 1526 | inet_listen_unlock(&tcp_hashinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1527 | local_bh_disable(); |
| 1528 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
| 1529 | rc = established_get_idx(seq, pos); |
| 1530 | } |
| 1531 | |
| 1532 | return rc; |
| 1533 | } |
| 1534 | |
| 1535 | static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) |
| 1536 | { |
| 1537 | struct tcp_iter_state* st = seq->private; |
| 1538 | st->state = TCP_SEQ_STATE_LISTENING; |
| 1539 | st->num = 0; |
| 1540 | return *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; |
| 1541 | } |
| 1542 | |
| 1543 | static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 1544 | { |
| 1545 | void *rc = NULL; |
| 1546 | struct tcp_iter_state* st; |
| 1547 | |
| 1548 | if (v == SEQ_START_TOKEN) { |
| 1549 | rc = tcp_get_idx(seq, 0); |
| 1550 | goto out; |
| 1551 | } |
| 1552 | st = seq->private; |
| 1553 | |
| 1554 | switch (st->state) { |
| 1555 | case TCP_SEQ_STATE_OPENREQ: |
| 1556 | case TCP_SEQ_STATE_LISTENING: |
| 1557 | rc = listening_get_next(seq, v); |
| 1558 | if (!rc) { |
Arnaldo Carvalho de Melo | f3f05f7 | 2005-08-09 20:08:09 -0700 | [diff] [blame] | 1559 | inet_listen_unlock(&tcp_hashinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1560 | local_bh_disable(); |
| 1561 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
| 1562 | rc = established_get_first(seq); |
| 1563 | } |
| 1564 | break; |
| 1565 | case TCP_SEQ_STATE_ESTABLISHED: |
| 1566 | case TCP_SEQ_STATE_TIME_WAIT: |
| 1567 | rc = established_get_next(seq, v); |
| 1568 | break; |
| 1569 | } |
| 1570 | out: |
| 1571 | ++*pos; |
| 1572 | return rc; |
| 1573 | } |
| 1574 | |
| 1575 | static void tcp_seq_stop(struct seq_file *seq, void *v) |
| 1576 | { |
| 1577 | struct tcp_iter_state* st = seq->private; |
| 1578 | |
| 1579 | switch (st->state) { |
| 1580 | case TCP_SEQ_STATE_OPENREQ: |
| 1581 | if (v) { |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1582 | struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk); |
| 1583 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1584 | } |
| 1585 | case TCP_SEQ_STATE_LISTENING: |
| 1586 | if (v != SEQ_START_TOKEN) |
Arnaldo Carvalho de Melo | f3f05f7 | 2005-08-09 20:08:09 -0700 | [diff] [blame] | 1587 | inet_listen_unlock(&tcp_hashinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1588 | break; |
| 1589 | case TCP_SEQ_STATE_TIME_WAIT: |
| 1590 | case TCP_SEQ_STATE_ESTABLISHED: |
| 1591 | if (v) |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 1592 | read_unlock(&tcp_hashinfo.ehash[st->bucket].lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1593 | local_bh_enable(); |
| 1594 | break; |
| 1595 | } |
| 1596 | } |
| 1597 | |
| 1598 | static int tcp_seq_open(struct inode *inode, struct file *file) |
| 1599 | { |
| 1600 | struct tcp_seq_afinfo *afinfo = PDE(inode)->data; |
| 1601 | struct seq_file *seq; |
| 1602 | struct tcp_iter_state *s; |
| 1603 | int rc; |
| 1604 | |
| 1605 | if (unlikely(afinfo == NULL)) |
| 1606 | return -EINVAL; |
| 1607 | |
| 1608 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
| 1609 | if (!s) |
| 1610 | return -ENOMEM; |
| 1611 | memset(s, 0, sizeof(*s)); |
| 1612 | s->family = afinfo->family; |
| 1613 | s->seq_ops.start = tcp_seq_start; |
| 1614 | s->seq_ops.next = tcp_seq_next; |
| 1615 | s->seq_ops.show = afinfo->seq_show; |
| 1616 | s->seq_ops.stop = tcp_seq_stop; |
| 1617 | |
| 1618 | rc = seq_open(file, &s->seq_ops); |
| 1619 | if (rc) |
| 1620 | goto out_kfree; |
| 1621 | seq = file->private_data; |
| 1622 | seq->private = s; |
| 1623 | out: |
| 1624 | return rc; |
| 1625 | out_kfree: |
| 1626 | kfree(s); |
| 1627 | goto out; |
| 1628 | } |
| 1629 | |
| 1630 | int tcp_proc_register(struct tcp_seq_afinfo *afinfo) |
| 1631 | { |
| 1632 | int rc = 0; |
| 1633 | struct proc_dir_entry *p; |
| 1634 | |
| 1635 | if (!afinfo) |
| 1636 | return -EINVAL; |
| 1637 | afinfo->seq_fops->owner = afinfo->owner; |
| 1638 | afinfo->seq_fops->open = tcp_seq_open; |
| 1639 | afinfo->seq_fops->read = seq_read; |
| 1640 | afinfo->seq_fops->llseek = seq_lseek; |
| 1641 | afinfo->seq_fops->release = seq_release_private; |
| 1642 | |
| 1643 | p = proc_net_fops_create(afinfo->name, S_IRUGO, afinfo->seq_fops); |
| 1644 | if (p) |
| 1645 | p->data = afinfo; |
| 1646 | else |
| 1647 | rc = -ENOMEM; |
| 1648 | return rc; |
| 1649 | } |
| 1650 | |
| 1651 | void tcp_proc_unregister(struct tcp_seq_afinfo *afinfo) |
| 1652 | { |
| 1653 | if (!afinfo) |
| 1654 | return; |
| 1655 | proc_net_remove(afinfo->name); |
| 1656 | memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops)); |
| 1657 | } |
| 1658 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 1659 | static void get_openreq4(struct sock *sk, struct request_sock *req, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1660 | char *tmpbuf, int i, int uid) |
| 1661 | { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1662 | const struct inet_request_sock *ireq = inet_rsk(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1663 | int ttd = req->expires - jiffies; |
| 1664 | |
| 1665 | sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" |
| 1666 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %p", |
| 1667 | i, |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1668 | ireq->loc_addr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1669 | ntohs(inet_sk(sk)->sport), |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1670 | ireq->rmt_addr, |
| 1671 | ntohs(ireq->rmt_port), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1672 | TCP_SYN_RECV, |
| 1673 | 0, 0, /* could print option size, but that is af dependent. */ |
| 1674 | 1, /* timers active (only the expire timer) */ |
| 1675 | jiffies_to_clock_t(ttd), |
| 1676 | req->retrans, |
| 1677 | uid, |
| 1678 | 0, /* non standard timer */ |
| 1679 | 0, /* open_requests have no inode */ |
| 1680 | atomic_read(&sk->sk_refcnt), |
| 1681 | req); |
| 1682 | } |
| 1683 | |
| 1684 | static void get_tcp4_sock(struct sock *sp, char *tmpbuf, int i) |
| 1685 | { |
| 1686 | int timer_active; |
| 1687 | unsigned long timer_expires; |
| 1688 | struct tcp_sock *tp = tcp_sk(sp); |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1689 | const struct inet_connection_sock *icsk = inet_csk(sp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1690 | struct inet_sock *inet = inet_sk(sp); |
| 1691 | unsigned int dest = inet->daddr; |
| 1692 | unsigned int src = inet->rcv_saddr; |
| 1693 | __u16 destp = ntohs(inet->dport); |
| 1694 | __u16 srcp = ntohs(inet->sport); |
| 1695 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1696 | if (icsk->icsk_pending == ICSK_TIME_RETRANS) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1697 | timer_active = 1; |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1698 | timer_expires = icsk->icsk_timeout; |
| 1699 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1700 | timer_active = 4; |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1701 | timer_expires = icsk->icsk_timeout; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1702 | } else if (timer_pending(&sp->sk_timer)) { |
| 1703 | timer_active = 2; |
| 1704 | timer_expires = sp->sk_timer.expires; |
| 1705 | } else { |
| 1706 | timer_active = 0; |
| 1707 | timer_expires = jiffies; |
| 1708 | } |
| 1709 | |
| 1710 | sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " |
| 1711 | "%08X %5d %8d %lu %d %p %u %u %u %u %d", |
| 1712 | i, src, srcp, dest, destp, sp->sk_state, |
| 1713 | tp->write_seq - tp->snd_una, tp->rcv_nxt - tp->copied_seq, |
| 1714 | timer_active, |
| 1715 | jiffies_to_clock_t(timer_expires - jiffies), |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1716 | icsk->icsk_retransmits, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1717 | sock_i_uid(sp), |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 1718 | icsk->icsk_probes_out, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1719 | sock_i_ino(sp), |
| 1720 | atomic_read(&sp->sk_refcnt), sp, |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1721 | icsk->icsk_rto, |
| 1722 | icsk->icsk_ack.ato, |
| 1723 | (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1724 | tp->snd_cwnd, |
| 1725 | tp->snd_ssthresh >= 0xFFFF ? -1 : tp->snd_ssthresh); |
| 1726 | } |
| 1727 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 1728 | static void get_timewait4_sock(struct inet_timewait_sock *tw, char *tmpbuf, int i) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1729 | { |
| 1730 | unsigned int dest, src; |
| 1731 | __u16 destp, srcp; |
| 1732 | int ttd = tw->tw_ttd - jiffies; |
| 1733 | |
| 1734 | if (ttd < 0) |
| 1735 | ttd = 0; |
| 1736 | |
| 1737 | dest = tw->tw_daddr; |
| 1738 | src = tw->tw_rcv_saddr; |
| 1739 | destp = ntohs(tw->tw_dport); |
| 1740 | srcp = ntohs(tw->tw_sport); |
| 1741 | |
| 1742 | sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" |
| 1743 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p", |
| 1744 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, |
| 1745 | 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, |
| 1746 | atomic_read(&tw->tw_refcnt), tw); |
| 1747 | } |
| 1748 | |
| 1749 | #define TMPSZ 150 |
| 1750 | |
| 1751 | static int tcp4_seq_show(struct seq_file *seq, void *v) |
| 1752 | { |
| 1753 | struct tcp_iter_state* st; |
| 1754 | char tmpbuf[TMPSZ + 1]; |
| 1755 | |
| 1756 | if (v == SEQ_START_TOKEN) { |
| 1757 | seq_printf(seq, "%-*s\n", TMPSZ - 1, |
| 1758 | " sl local_address rem_address st tx_queue " |
| 1759 | "rx_queue tr tm->when retrnsmt uid timeout " |
| 1760 | "inode"); |
| 1761 | goto out; |
| 1762 | } |
| 1763 | st = seq->private; |
| 1764 | |
| 1765 | switch (st->state) { |
| 1766 | case TCP_SEQ_STATE_LISTENING: |
| 1767 | case TCP_SEQ_STATE_ESTABLISHED: |
| 1768 | get_tcp4_sock(v, tmpbuf, st->num); |
| 1769 | break; |
| 1770 | case TCP_SEQ_STATE_OPENREQ: |
| 1771 | get_openreq4(st->syn_wait_sk, v, tmpbuf, st->num, st->uid); |
| 1772 | break; |
| 1773 | case TCP_SEQ_STATE_TIME_WAIT: |
| 1774 | get_timewait4_sock(v, tmpbuf, st->num); |
| 1775 | break; |
| 1776 | } |
| 1777 | seq_printf(seq, "%-*s\n", TMPSZ - 1, tmpbuf); |
| 1778 | out: |
| 1779 | return 0; |
| 1780 | } |
| 1781 | |
| 1782 | static struct file_operations tcp4_seq_fops; |
| 1783 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { |
| 1784 | .owner = THIS_MODULE, |
| 1785 | .name = "tcp", |
| 1786 | .family = AF_INET, |
| 1787 | .seq_show = tcp4_seq_show, |
| 1788 | .seq_fops = &tcp4_seq_fops, |
| 1789 | }; |
| 1790 | |
| 1791 | int __init tcp4_proc_init(void) |
| 1792 | { |
| 1793 | return tcp_proc_register(&tcp4_seq_afinfo); |
| 1794 | } |
| 1795 | |
| 1796 | void tcp4_proc_exit(void) |
| 1797 | { |
| 1798 | tcp_proc_unregister(&tcp4_seq_afinfo); |
| 1799 | } |
| 1800 | #endif /* CONFIG_PROC_FS */ |
| 1801 | |
| 1802 | struct proto tcp_prot = { |
| 1803 | .name = "TCP", |
| 1804 | .owner = THIS_MODULE, |
| 1805 | .close = tcp_close, |
| 1806 | .connect = tcp_v4_connect, |
| 1807 | .disconnect = tcp_disconnect, |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1808 | .accept = inet_csk_accept, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1809 | .ioctl = tcp_ioctl, |
| 1810 | .init = tcp_v4_init_sock, |
| 1811 | .destroy = tcp_v4_destroy_sock, |
| 1812 | .shutdown = tcp_shutdown, |
| 1813 | .setsockopt = tcp_setsockopt, |
| 1814 | .getsockopt = tcp_getsockopt, |
| 1815 | .sendmsg = tcp_sendmsg, |
| 1816 | .recvmsg = tcp_recvmsg, |
| 1817 | .backlog_rcv = tcp_v4_do_rcv, |
| 1818 | .hash = tcp_v4_hash, |
| 1819 | .unhash = tcp_unhash, |
| 1820 | .get_port = tcp_v4_get_port, |
| 1821 | .enter_memory_pressure = tcp_enter_memory_pressure, |
| 1822 | .sockets_allocated = &tcp_sockets_allocated, |
Arnaldo Carvalho de Melo | 0a5578c | 2005-08-09 20:11:41 -0700 | [diff] [blame] | 1823 | .orphan_count = &tcp_orphan_count, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1824 | .memory_allocated = &tcp_memory_allocated, |
| 1825 | .memory_pressure = &tcp_memory_pressure, |
| 1826 | .sysctl_mem = sysctl_tcp_mem, |
| 1827 | .sysctl_wmem = sysctl_tcp_wmem, |
| 1828 | .sysctl_rmem = sysctl_tcp_rmem, |
| 1829 | .max_header = MAX_TCP_HEADER, |
| 1830 | .obj_size = sizeof(struct tcp_sock), |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 1831 | .twsk_prot = &tcp_timewait_sock_ops, |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 1832 | .rsk_prot = &tcp_request_sock_ops, |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 1833 | #ifdef CONFIG_COMPAT |
| 1834 | .compat_setsockopt = compat_tcp_setsockopt, |
| 1835 | .compat_getsockopt = compat_tcp_getsockopt, |
| 1836 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1837 | }; |
| 1838 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1839 | void __init tcp_v4_init(struct net_proto_family *ops) |
| 1840 | { |
Arnaldo Carvalho de Melo | c4d9390 | 2006-03-20 22:01:03 -0800 | [diff] [blame] | 1841 | if (inet_csk_ctl_sock_create(&tcp_socket, PF_INET, SOCK_RAW, IPPROTO_TCP) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1842 | panic("Failed to create the TCP control socket.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1843 | } |
| 1844 | |
| 1845 | EXPORT_SYMBOL(ipv4_specific); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1846 | EXPORT_SYMBOL(tcp_hashinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1847 | EXPORT_SYMBOL(tcp_prot); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1848 | EXPORT_SYMBOL(tcp_unhash); |
| 1849 | EXPORT_SYMBOL(tcp_v4_conn_request); |
| 1850 | EXPORT_SYMBOL(tcp_v4_connect); |
| 1851 | EXPORT_SYMBOL(tcp_v4_do_rcv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1852 | EXPORT_SYMBOL(tcp_v4_remember_stamp); |
| 1853 | EXPORT_SYMBOL(tcp_v4_send_check); |
| 1854 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); |
| 1855 | |
| 1856 | #ifdef CONFIG_PROC_FS |
| 1857 | EXPORT_SYMBOL(tcp_proc_register); |
| 1858 | EXPORT_SYMBOL(tcp_proc_unregister); |
| 1859 | #endif |
| 1860 | EXPORT_SYMBOL(sysctl_local_port_range); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1861 | EXPORT_SYMBOL(sysctl_tcp_low_latency); |
| 1862 | EXPORT_SYMBOL(sysctl_tcp_tw_reuse); |
| 1863 | |