Commit | Line | Data |
---|---|---|
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 | * | |
1da177e4 LT |
8 | * IPv4 specific functions |
9 | * | |
10 | * | |
11 | * code split from: | |
12 | * linux/ipv4/tcp.c | |
13 | * linux/ipv4/tcp_input.c | |
14 | * linux/ipv4/tcp_output.c | |
15 | * | |
16 | * See tcp.c for author information | |
17 | * | |
18 | * This program is free software; you can redistribute it and/or | |
19 | * modify it under the terms of the GNU General Public License | |
20 | * as published by the Free Software Foundation; either version | |
21 | * 2 of the License, or (at your option) any later version. | |
22 | */ | |
23 | ||
24 | /* | |
25 | * Changes: | |
26 | * David S. Miller : New socket lookup architecture. | |
27 | * This code is dedicated to John Dyson. | |
28 | * David S. Miller : Change semantics of established hash, | |
29 | * half is devoted to TIME_WAIT sockets | |
30 | * and the rest go in the other half. | |
31 | * Andi Kleen : Add support for syncookies and fixed | |
32 | * some bugs: ip options weren't passed to | |
33 | * the TCP layer, missed a check for an | |
34 | * ACK bit. | |
35 | * Andi Kleen : Implemented fast path mtu discovery. | |
36 | * Fixed many serious bugs in the | |
60236fdd | 37 | * request_sock handling and moved |
1da177e4 LT |
38 | * most of it into the af independent code. |
39 | * Added tail drop and some other bugfixes. | |
caa20d9a | 40 | * Added new listen semantics. |
1da177e4 LT |
41 | * Mike McLagan : Routing by source |
42 | * Juan Jose Ciarlante: ip_dynaddr bits | |
43 | * Andi Kleen: various fixes. | |
44 | * Vitaly E. Lavrov : Transparent proxy revived after year | |
45 | * coma. | |
46 | * Andi Kleen : Fix new listen. | |
47 | * Andi Kleen : Fix accept error reporting. | |
48 | * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which | |
49 | * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind | |
50 | * a single port at the same time. | |
51 | */ | |
52 | ||
1da177e4 | 53 | |
eb4dea58 | 54 | #include <linux/bottom_half.h> |
1da177e4 LT |
55 | #include <linux/types.h> |
56 | #include <linux/fcntl.h> | |
57 | #include <linux/module.h> | |
58 | #include <linux/random.h> | |
59 | #include <linux/cache.h> | |
60 | #include <linux/jhash.h> | |
61 | #include <linux/init.h> | |
62 | #include <linux/times.h> | |
5a0e3ad6 | 63 | #include <linux/slab.h> |
1da177e4 | 64 | |
457c4cbc | 65 | #include <net/net_namespace.h> |
1da177e4 | 66 | #include <net/icmp.h> |
304a1618 | 67 | #include <net/inet_hashtables.h> |
1da177e4 | 68 | #include <net/tcp.h> |
20380731 | 69 | #include <net/transp_v6.h> |
1da177e4 LT |
70 | #include <net/ipv6.h> |
71 | #include <net/inet_common.h> | |
6d6ee43e | 72 | #include <net/timewait_sock.h> |
1da177e4 | 73 | #include <net/xfrm.h> |
1a2449a8 | 74 | #include <net/netdma.h> |
6e5714ea | 75 | #include <net/secure_seq.h> |
d1a4c0b3 | 76 | #include <net/tcp_memcontrol.h> |
1da177e4 LT |
77 | |
78 | #include <linux/inet.h> | |
79 | #include <linux/ipv6.h> | |
80 | #include <linux/stddef.h> | |
81 | #include <linux/proc_fs.h> | |
82 | #include <linux/seq_file.h> | |
83 | ||
cfb6eeb4 YH |
84 | #include <linux/crypto.h> |
85 | #include <linux/scatterlist.h> | |
86 | ||
ab32ea5d BH |
87 | int sysctl_tcp_tw_reuse __read_mostly; |
88 | int sysctl_tcp_low_latency __read_mostly; | |
4bc2f18b | 89 | EXPORT_SYMBOL(sysctl_tcp_low_latency); |
1da177e4 | 90 | |
1da177e4 | 91 | |
cfb6eeb4 | 92 | #ifdef CONFIG_TCP_MD5SIG |
7174259e ACM |
93 | static struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, |
94 | __be32 addr); | |
49a72dfb | 95 | static int tcp_v4_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, |
318cf7aa | 96 | __be32 daddr, __be32 saddr, const struct tcphdr *th); |
9501f972 YH |
97 | #else |
98 | static inline | |
99 | struct tcp_md5sig_key *tcp_v4_md5_do_lookup(struct sock *sk, __be32 addr) | |
100 | { | |
101 | return NULL; | |
102 | } | |
cfb6eeb4 YH |
103 | #endif |
104 | ||
5caea4ea | 105 | struct inet_hashinfo tcp_hashinfo; |
4bc2f18b | 106 | EXPORT_SYMBOL(tcp_hashinfo); |
1da177e4 | 107 | |
cf533ea5 | 108 | static inline __u32 tcp_v4_init_sequence(const struct sk_buff *skb) |
1da177e4 | 109 | { |
eddc9ec5 ACM |
110 | return secure_tcp_sequence_number(ip_hdr(skb)->daddr, |
111 | ip_hdr(skb)->saddr, | |
aa8223c7 ACM |
112 | tcp_hdr(skb)->dest, |
113 | tcp_hdr(skb)->source); | |
1da177e4 LT |
114 | } |
115 | ||
6d6ee43e ACM |
116 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) |
117 | { | |
118 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); | |
119 | struct tcp_sock *tp = tcp_sk(sk); | |
120 | ||
121 | /* With PAWS, it is safe from the viewpoint | |
122 | of data integrity. Even without PAWS it is safe provided sequence | |
123 | spaces do not overlap i.e. at data rates <= 80Mbit/sec. | |
124 | ||
125 | Actually, the idea is close to VJ's one, only timestamp cache is | |
126 | held not per host, but per port pair and TW bucket is used as state | |
127 | holder. | |
128 | ||
129 | If TW bucket has been already destroyed we fall back to VJ's scheme | |
130 | and use initial timestamp retrieved from peer table. | |
131 | */ | |
132 | if (tcptw->tw_ts_recent_stamp && | |
133 | (twp == NULL || (sysctl_tcp_tw_reuse && | |
9d729f72 | 134 | get_seconds() - tcptw->tw_ts_recent_stamp > 1))) { |
6d6ee43e ACM |
135 | tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; |
136 | if (tp->write_seq == 0) | |
137 | tp->write_seq = 1; | |
138 | tp->rx_opt.ts_recent = tcptw->tw_ts_recent; | |
139 | tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; | |
140 | sock_hold(sktw); | |
141 | return 1; | |
142 | } | |
143 | ||
144 | return 0; | |
145 | } | |
6d6ee43e ACM |
146 | EXPORT_SYMBOL_GPL(tcp_twsk_unique); |
147 | ||
1da177e4 LT |
148 | /* This will initiate an outgoing connection. */ |
149 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
150 | { | |
2d7192d6 | 151 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
1da177e4 LT |
152 | struct inet_sock *inet = inet_sk(sk); |
153 | struct tcp_sock *tp = tcp_sk(sk); | |
dca8b089 | 154 | __be16 orig_sport, orig_dport; |
bada8adc | 155 | __be32 daddr, nexthop; |
da905bd1 | 156 | struct flowi4 *fl4; |
2d7192d6 | 157 | struct rtable *rt; |
1da177e4 | 158 | int err; |
f6d8bd05 | 159 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
160 | |
161 | if (addr_len < sizeof(struct sockaddr_in)) | |
162 | return -EINVAL; | |
163 | ||
164 | if (usin->sin_family != AF_INET) | |
165 | return -EAFNOSUPPORT; | |
166 | ||
167 | nexthop = daddr = usin->sin_addr.s_addr; | |
f6d8bd05 ED |
168 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
169 | sock_owned_by_user(sk)); | |
170 | if (inet_opt && inet_opt->opt.srr) { | |
1da177e4 LT |
171 | if (!daddr) |
172 | return -EINVAL; | |
f6d8bd05 | 173 | nexthop = inet_opt->opt.faddr; |
1da177e4 LT |
174 | } |
175 | ||
dca8b089 DM |
176 | orig_sport = inet->inet_sport; |
177 | orig_dport = usin->sin_port; | |
da905bd1 DM |
178 | fl4 = &inet->cork.fl.u.ip4; |
179 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, | |
b23dd4fe DM |
180 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
181 | IPPROTO_TCP, | |
182 | orig_sport, orig_dport, sk, true); | |
183 | if (IS_ERR(rt)) { | |
184 | err = PTR_ERR(rt); | |
185 | if (err == -ENETUNREACH) | |
7c73a6fa | 186 | IP_INC_STATS_BH(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
b23dd4fe | 187 | return err; |
584bdf8c | 188 | } |
1da177e4 LT |
189 | |
190 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
191 | ip_rt_put(rt); | |
192 | return -ENETUNREACH; | |
193 | } | |
194 | ||
f6d8bd05 | 195 | if (!inet_opt || !inet_opt->opt.srr) |
da905bd1 | 196 | daddr = fl4->daddr; |
1da177e4 | 197 | |
c720c7e8 | 198 | if (!inet->inet_saddr) |
da905bd1 | 199 | inet->inet_saddr = fl4->saddr; |
c720c7e8 | 200 | inet->inet_rcv_saddr = inet->inet_saddr; |
1da177e4 | 201 | |
c720c7e8 | 202 | if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { |
1da177e4 LT |
203 | /* Reset inherited state */ |
204 | tp->rx_opt.ts_recent = 0; | |
205 | tp->rx_opt.ts_recent_stamp = 0; | |
206 | tp->write_seq = 0; | |
207 | } | |
208 | ||
295ff7ed | 209 | if (tcp_death_row.sysctl_tw_recycle && |
da905bd1 | 210 | !tp->rx_opt.ts_recent_stamp && fl4->daddr == daddr) { |
ed2361e6 | 211 | struct inet_peer *peer = rt_get_peer(rt, fl4->daddr); |
7174259e ACM |
212 | /* |
213 | * VJ's idea. We save last timestamp seen from | |
214 | * the destination in peer table, when entering state | |
215 | * TIME-WAIT * and initialize rx_opt.ts_recent from it, | |
216 | * when trying new connection. | |
1da177e4 | 217 | */ |
317fe0e6 ED |
218 | if (peer) { |
219 | inet_peer_refcheck(peer); | |
220 | if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) { | |
221 | tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp; | |
222 | tp->rx_opt.ts_recent = peer->tcp_ts; | |
223 | } | |
1da177e4 LT |
224 | } |
225 | } | |
226 | ||
c720c7e8 ED |
227 | inet->inet_dport = usin->sin_port; |
228 | inet->inet_daddr = daddr; | |
1da177e4 | 229 | |
d83d8461 | 230 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
231 | if (inet_opt) |
232 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
1da177e4 | 233 | |
bee7ca9e | 234 | tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; |
1da177e4 LT |
235 | |
236 | /* Socket identity is still unknown (sport may be zero). | |
237 | * However we set state to SYN-SENT and not releasing socket | |
238 | * lock select source port, enter ourselves into the hash tables and | |
239 | * complete initialization after this. | |
240 | */ | |
241 | tcp_set_state(sk, TCP_SYN_SENT); | |
a7f5e7f1 | 242 | err = inet_hash_connect(&tcp_death_row, sk); |
1da177e4 LT |
243 | if (err) |
244 | goto failure; | |
245 | ||
da905bd1 | 246 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
b23dd4fe DM |
247 | inet->inet_sport, inet->inet_dport, sk); |
248 | if (IS_ERR(rt)) { | |
249 | err = PTR_ERR(rt); | |
250 | rt = NULL; | |
1da177e4 | 251 | goto failure; |
b23dd4fe | 252 | } |
1da177e4 | 253 | /* OK, now commit destination to socket. */ |
bcd76111 | 254 | sk->sk_gso_type = SKB_GSO_TCPV4; |
d8d1f30b | 255 | sk_setup_caps(sk, &rt->dst); |
1da177e4 LT |
256 | |
257 | if (!tp->write_seq) | |
c720c7e8 ED |
258 | tp->write_seq = secure_tcp_sequence_number(inet->inet_saddr, |
259 | inet->inet_daddr, | |
260 | inet->inet_sport, | |
1da177e4 LT |
261 | usin->sin_port); |
262 | ||
c720c7e8 | 263 | inet->inet_id = tp->write_seq ^ jiffies; |
1da177e4 LT |
264 | |
265 | err = tcp_connect(sk); | |
266 | rt = NULL; | |
267 | if (err) | |
268 | goto failure; | |
269 | ||
270 | return 0; | |
271 | ||
272 | failure: | |
7174259e ACM |
273 | /* |
274 | * This unhashes the socket and releases the local port, | |
275 | * if necessary. | |
276 | */ | |
1da177e4 LT |
277 | tcp_set_state(sk, TCP_CLOSE); |
278 | ip_rt_put(rt); | |
279 | sk->sk_route_caps = 0; | |
c720c7e8 | 280 | inet->inet_dport = 0; |
1da177e4 LT |
281 | return err; |
282 | } | |
4bc2f18b | 283 | EXPORT_SYMBOL(tcp_v4_connect); |
1da177e4 | 284 | |
1da177e4 LT |
285 | /* |
286 | * This routine does path mtu discovery as defined in RFC1191. | |
287 | */ | |
b71d1d42 | 288 | static void do_pmtu_discovery(struct sock *sk, const struct iphdr *iph, u32 mtu) |
1da177e4 LT |
289 | { |
290 | struct dst_entry *dst; | |
291 | struct inet_sock *inet = inet_sk(sk); | |
1da177e4 LT |
292 | |
293 | /* We are not interested in TCP_LISTEN and open_requests (SYN-ACKs | |
294 | * send out by Linux are always <576bytes so they should go through | |
295 | * unfragmented). | |
296 | */ | |
297 | if (sk->sk_state == TCP_LISTEN) | |
298 | return; | |
299 | ||
300 | /* We don't check in the destentry if pmtu discovery is forbidden | |
301 | * on this route. We just assume that no packet_to_big packets | |
302 | * are send back when pmtu discovery is not active. | |
e905a9ed | 303 | * There is a small race when the user changes this flag in the |
1da177e4 LT |
304 | * route, but I think that's acceptable. |
305 | */ | |
306 | if ((dst = __sk_dst_check(sk, 0)) == NULL) | |
307 | return; | |
308 | ||
309 | dst->ops->update_pmtu(dst, mtu); | |
310 | ||
311 | /* Something is about to be wrong... Remember soft error | |
312 | * for the case, if this connection will not able to recover. | |
313 | */ | |
314 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
315 | sk->sk_err_soft = EMSGSIZE; | |
316 | ||
317 | mtu = dst_mtu(dst); | |
318 | ||
319 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
d83d8461 | 320 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
1da177e4 LT |
321 | tcp_sync_mss(sk, mtu); |
322 | ||
323 | /* Resend the TCP packet because it's | |
324 | * clear that the old packet has been | |
325 | * dropped. This is the new "fast" path mtu | |
326 | * discovery. | |
327 | */ | |
328 | tcp_simple_retransmit(sk); | |
329 | } /* else let the usual retransmit timer handle it */ | |
330 | } | |
331 | ||
332 | /* | |
333 | * This routine is called by the ICMP module when it gets some | |
334 | * sort of error condition. If err < 0 then the socket should | |
335 | * be closed and the error returned to the user. If err > 0 | |
336 | * it's just the icmp type << 8 | icmp code. After adjustment | |
337 | * header points to the first 8 bytes of the tcp header. We need | |
338 | * to find the appropriate port. | |
339 | * | |
340 | * The locking strategy used here is very "optimistic". When | |
341 | * someone else accesses the socket the ICMP is just dropped | |
342 | * and for some paths there is no check at all. | |
343 | * A more general error queue to queue errors for later handling | |
344 | * is probably better. | |
345 | * | |
346 | */ | |
347 | ||
4d1a2d9e | 348 | void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) |
1da177e4 | 349 | { |
b71d1d42 | 350 | const struct iphdr *iph = (const struct iphdr *)icmp_skb->data; |
4d1a2d9e | 351 | struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2)); |
f1ecd5d9 | 352 | struct inet_connection_sock *icsk; |
1da177e4 LT |
353 | struct tcp_sock *tp; |
354 | struct inet_sock *inet; | |
4d1a2d9e DL |
355 | const int type = icmp_hdr(icmp_skb)->type; |
356 | const int code = icmp_hdr(icmp_skb)->code; | |
1da177e4 | 357 | struct sock *sk; |
f1ecd5d9 | 358 | struct sk_buff *skb; |
1da177e4 | 359 | __u32 seq; |
f1ecd5d9 | 360 | __u32 remaining; |
1da177e4 | 361 | int err; |
4d1a2d9e | 362 | struct net *net = dev_net(icmp_skb->dev); |
1da177e4 | 363 | |
4d1a2d9e | 364 | if (icmp_skb->len < (iph->ihl << 2) + 8) { |
dcfc23ca | 365 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
366 | return; |
367 | } | |
368 | ||
fd54d716 | 369 | sk = inet_lookup(net, &tcp_hashinfo, iph->daddr, th->dest, |
4d1a2d9e | 370 | iph->saddr, th->source, inet_iif(icmp_skb)); |
1da177e4 | 371 | if (!sk) { |
dcfc23ca | 372 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
373 | return; |
374 | } | |
375 | if (sk->sk_state == TCP_TIME_WAIT) { | |
9469c7b4 | 376 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
377 | return; |
378 | } | |
379 | ||
380 | bh_lock_sock(sk); | |
381 | /* If too many ICMPs get dropped on busy | |
382 | * servers this needs to be solved differently. | |
383 | */ | |
384 | if (sock_owned_by_user(sk)) | |
de0744af | 385 | NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); |
1da177e4 LT |
386 | |
387 | if (sk->sk_state == TCP_CLOSE) | |
388 | goto out; | |
389 | ||
97e3ecd1 | 390 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
391 | NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); | |
392 | goto out; | |
393 | } | |
394 | ||
f1ecd5d9 | 395 | icsk = inet_csk(sk); |
1da177e4 LT |
396 | tp = tcp_sk(sk); |
397 | seq = ntohl(th->seq); | |
398 | if (sk->sk_state != TCP_LISTEN && | |
399 | !between(seq, tp->snd_una, tp->snd_nxt)) { | |
de0744af | 400 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
401 | goto out; |
402 | } | |
403 | ||
404 | switch (type) { | |
405 | case ICMP_SOURCE_QUENCH: | |
406 | /* Just silently ignore these. */ | |
407 | goto out; | |
408 | case ICMP_PARAMETERPROB: | |
409 | err = EPROTO; | |
410 | break; | |
411 | case ICMP_DEST_UNREACH: | |
412 | if (code > NR_ICMP_UNREACH) | |
413 | goto out; | |
414 | ||
415 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
416 | if (!sock_owned_by_user(sk)) | |
417 | do_pmtu_discovery(sk, iph, info); | |
418 | goto out; | |
419 | } | |
420 | ||
421 | err = icmp_err_convert[code].errno; | |
f1ecd5d9 DL |
422 | /* check if icmp_skb allows revert of backoff |
423 | * (see draft-zimmermann-tcp-lcd) */ | |
424 | if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH) | |
425 | break; | |
426 | if (seq != tp->snd_una || !icsk->icsk_retransmits || | |
427 | !icsk->icsk_backoff) | |
428 | break; | |
429 | ||
8f49c270 DM |
430 | if (sock_owned_by_user(sk)) |
431 | break; | |
432 | ||
f1ecd5d9 | 433 | icsk->icsk_backoff--; |
9ad7c049 JC |
434 | inet_csk(sk)->icsk_rto = (tp->srtt ? __tcp_set_rto(tp) : |
435 | TCP_TIMEOUT_INIT) << icsk->icsk_backoff; | |
f1ecd5d9 DL |
436 | tcp_bound_rto(sk); |
437 | ||
438 | skb = tcp_write_queue_head(sk); | |
439 | BUG_ON(!skb); | |
440 | ||
441 | remaining = icsk->icsk_rto - min(icsk->icsk_rto, | |
442 | tcp_time_stamp - TCP_SKB_CB(skb)->when); | |
443 | ||
444 | if (remaining) { | |
445 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, | |
446 | remaining, TCP_RTO_MAX); | |
f1ecd5d9 DL |
447 | } else { |
448 | /* RTO revert clocked out retransmission. | |
449 | * Will retransmit now */ | |
450 | tcp_retransmit_timer(sk); | |
451 | } | |
452 | ||
1da177e4 LT |
453 | break; |
454 | case ICMP_TIME_EXCEEDED: | |
455 | err = EHOSTUNREACH; | |
456 | break; | |
457 | default: | |
458 | goto out; | |
459 | } | |
460 | ||
461 | switch (sk->sk_state) { | |
60236fdd | 462 | struct request_sock *req, **prev; |
1da177e4 LT |
463 | case TCP_LISTEN: |
464 | if (sock_owned_by_user(sk)) | |
465 | goto out; | |
466 | ||
463c84b9 ACM |
467 | req = inet_csk_search_req(sk, &prev, th->dest, |
468 | iph->daddr, iph->saddr); | |
1da177e4 LT |
469 | if (!req) |
470 | goto out; | |
471 | ||
472 | /* ICMPs are not backlogged, hence we cannot get | |
473 | an established socket here. | |
474 | */ | |
547b792c | 475 | WARN_ON(req->sk); |
1da177e4 | 476 | |
2e6599cb | 477 | if (seq != tcp_rsk(req)->snt_isn) { |
de0744af | 478 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
479 | goto out; |
480 | } | |
481 | ||
482 | /* | |
483 | * Still in SYN_RECV, just remove it silently. | |
484 | * There is no good way to pass the error to the newly | |
485 | * created socket, and POSIX does not want network | |
486 | * errors returned from accept(). | |
487 | */ | |
463c84b9 | 488 | inet_csk_reqsk_queue_drop(sk, req, prev); |
1da177e4 LT |
489 | goto out; |
490 | ||
491 | case TCP_SYN_SENT: | |
492 | case TCP_SYN_RECV: /* Cannot happen. | |
493 | It can f.e. if SYNs crossed. | |
494 | */ | |
495 | if (!sock_owned_by_user(sk)) { | |
1da177e4 LT |
496 | sk->sk_err = err; |
497 | ||
498 | sk->sk_error_report(sk); | |
499 | ||
500 | tcp_done(sk); | |
501 | } else { | |
502 | sk->sk_err_soft = err; | |
503 | } | |
504 | goto out; | |
505 | } | |
506 | ||
507 | /* If we've already connected we will keep trying | |
508 | * until we time out, or the user gives up. | |
509 | * | |
510 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
511 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
512 | * but it is obsoleted by pmtu discovery). | |
513 | * | |
514 | * Note, that in modern internet, where routing is unreliable | |
515 | * and in each dark corner broken firewalls sit, sending random | |
516 | * errors ordered by their masters even this two messages finally lose | |
517 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
518 | * | |
519 | * Now we are in compliance with RFCs. | |
520 | * --ANK (980905) | |
521 | */ | |
522 | ||
523 | inet = inet_sk(sk); | |
524 | if (!sock_owned_by_user(sk) && inet->recverr) { | |
525 | sk->sk_err = err; | |
526 | sk->sk_error_report(sk); | |
527 | } else { /* Only an error on timeout */ | |
528 | sk->sk_err_soft = err; | |
529 | } | |
530 | ||
531 | out: | |
532 | bh_unlock_sock(sk); | |
533 | sock_put(sk); | |
534 | } | |
535 | ||
419f9f89 HX |
536 | static void __tcp_v4_send_check(struct sk_buff *skb, |
537 | __be32 saddr, __be32 daddr) | |
1da177e4 | 538 | { |
aa8223c7 | 539 | struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 540 | |
84fa7933 | 541 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
419f9f89 | 542 | th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); |
663ead3b | 543 | skb->csum_start = skb_transport_header(skb) - skb->head; |
ff1dcadb | 544 | skb->csum_offset = offsetof(struct tcphdr, check); |
1da177e4 | 545 | } else { |
419f9f89 | 546 | th->check = tcp_v4_check(skb->len, saddr, daddr, |
07f0757a | 547 | csum_partial(th, |
1da177e4 LT |
548 | th->doff << 2, |
549 | skb->csum)); | |
550 | } | |
551 | } | |
552 | ||
419f9f89 | 553 | /* This routine computes an IPv4 TCP checksum. */ |
bb296246 | 554 | void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
419f9f89 | 555 | { |
cf533ea5 | 556 | const struct inet_sock *inet = inet_sk(sk); |
419f9f89 HX |
557 | |
558 | __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); | |
559 | } | |
4bc2f18b | 560 | EXPORT_SYMBOL(tcp_v4_send_check); |
419f9f89 | 561 | |
a430a43d HX |
562 | int tcp_v4_gso_send_check(struct sk_buff *skb) |
563 | { | |
eddc9ec5 | 564 | const struct iphdr *iph; |
a430a43d HX |
565 | struct tcphdr *th; |
566 | ||
567 | if (!pskb_may_pull(skb, sizeof(*th))) | |
568 | return -EINVAL; | |
569 | ||
eddc9ec5 | 570 | iph = ip_hdr(skb); |
aa8223c7 | 571 | th = tcp_hdr(skb); |
a430a43d HX |
572 | |
573 | th->check = 0; | |
84fa7933 | 574 | skb->ip_summed = CHECKSUM_PARTIAL; |
419f9f89 | 575 | __tcp_v4_send_check(skb, iph->saddr, iph->daddr); |
a430a43d HX |
576 | return 0; |
577 | } | |
578 | ||
1da177e4 LT |
579 | /* |
580 | * This routine will send an RST to the other tcp. | |
581 | * | |
582 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) | |
583 | * for reset. | |
584 | * Answer: if a packet caused RST, it is not for a socket | |
585 | * existing in our system, if it is matched to a socket, | |
586 | * it is just duplicate segment or bug in other side's TCP. | |
587 | * So that we build reply only basing on parameters | |
588 | * arrived with segment. | |
589 | * Exception: precedence violation. We do not implement it in any case. | |
590 | */ | |
591 | ||
cfb6eeb4 | 592 | static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 593 | { |
cf533ea5 | 594 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
595 | struct { |
596 | struct tcphdr th; | |
597 | #ifdef CONFIG_TCP_MD5SIG | |
714e85be | 598 | __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)]; |
cfb6eeb4 YH |
599 | #endif |
600 | } rep; | |
1da177e4 | 601 | struct ip_reply_arg arg; |
cfb6eeb4 YH |
602 | #ifdef CONFIG_TCP_MD5SIG |
603 | struct tcp_md5sig_key *key; | |
604 | #endif | |
a86b1e30 | 605 | struct net *net; |
1da177e4 LT |
606 | |
607 | /* Never send a reset in response to a reset. */ | |
608 | if (th->rst) | |
609 | return; | |
610 | ||
511c3f92 | 611 | if (skb_rtable(skb)->rt_type != RTN_LOCAL) |
1da177e4 LT |
612 | return; |
613 | ||
614 | /* Swap the send and the receive. */ | |
cfb6eeb4 YH |
615 | memset(&rep, 0, sizeof(rep)); |
616 | rep.th.dest = th->source; | |
617 | rep.th.source = th->dest; | |
618 | rep.th.doff = sizeof(struct tcphdr) / 4; | |
619 | rep.th.rst = 1; | |
1da177e4 LT |
620 | |
621 | if (th->ack) { | |
cfb6eeb4 | 622 | rep.th.seq = th->ack_seq; |
1da177e4 | 623 | } else { |
cfb6eeb4 YH |
624 | rep.th.ack = 1; |
625 | rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + | |
626 | skb->len - (th->doff << 2)); | |
1da177e4 LT |
627 | } |
628 | ||
7174259e | 629 | memset(&arg, 0, sizeof(arg)); |
cfb6eeb4 YH |
630 | arg.iov[0].iov_base = (unsigned char *)&rep; |
631 | arg.iov[0].iov_len = sizeof(rep.th); | |
632 | ||
633 | #ifdef CONFIG_TCP_MD5SIG | |
eddc9ec5 | 634 | key = sk ? tcp_v4_md5_do_lookup(sk, ip_hdr(skb)->daddr) : NULL; |
cfb6eeb4 YH |
635 | if (key) { |
636 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | | |
637 | (TCPOPT_NOP << 16) | | |
638 | (TCPOPT_MD5SIG << 8) | | |
639 | TCPOLEN_MD5SIG); | |
640 | /* Update length and the length the header thinks exists */ | |
641 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
642 | rep.th.doff = arg.iov[0].iov_len / 4; | |
643 | ||
49a72dfb | 644 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], |
78e645cb IJ |
645 | key, ip_hdr(skb)->saddr, |
646 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
647 | } |
648 | #endif | |
eddc9ec5 ACM |
649 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
650 | ip_hdr(skb)->saddr, /* XXX */ | |
52cd5750 | 651 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
1da177e4 | 652 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
88ef4a5a | 653 | arg.flags = (sk && inet_sk(sk)->transparent) ? IP_REPLY_ARG_NOSRCCHECK : 0; |
1da177e4 | 654 | |
adf30907 | 655 | net = dev_net(skb_dst(skb)->dev); |
66b13d99 | 656 | arg.tos = ip_hdr(skb)->tos; |
0a5ebb80 | 657 | ip_send_reply(net->ipv4.tcp_sock, skb, ip_hdr(skb)->saddr, |
7feb49c8 | 658 | &arg, arg.iov[0].iov_len); |
1da177e4 | 659 | |
63231bdd PE |
660 | TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); |
661 | TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); | |
1da177e4 LT |
662 | } |
663 | ||
664 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states | |
665 | outside socket context is ugly, certainly. What can I do? | |
666 | */ | |
667 | ||
9501f972 YH |
668 | static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack, |
669 | u32 win, u32 ts, int oif, | |
88ef4a5a | 670 | struct tcp_md5sig_key *key, |
66b13d99 | 671 | int reply_flags, u8 tos) |
1da177e4 | 672 | { |
cf533ea5 | 673 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 LT |
674 | struct { |
675 | struct tcphdr th; | |
714e85be | 676 | __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) |
cfb6eeb4 | 677 | #ifdef CONFIG_TCP_MD5SIG |
714e85be | 678 | + (TCPOLEN_MD5SIG_ALIGNED >> 2) |
cfb6eeb4 YH |
679 | #endif |
680 | ]; | |
1da177e4 LT |
681 | } rep; |
682 | struct ip_reply_arg arg; | |
adf30907 | 683 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 LT |
684 | |
685 | memset(&rep.th, 0, sizeof(struct tcphdr)); | |
7174259e | 686 | memset(&arg, 0, sizeof(arg)); |
1da177e4 LT |
687 | |
688 | arg.iov[0].iov_base = (unsigned char *)&rep; | |
689 | arg.iov[0].iov_len = sizeof(rep.th); | |
690 | if (ts) { | |
cfb6eeb4 YH |
691 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
692 | (TCPOPT_TIMESTAMP << 8) | | |
693 | TCPOLEN_TIMESTAMP); | |
694 | rep.opt[1] = htonl(tcp_time_stamp); | |
695 | rep.opt[2] = htonl(ts); | |
cb48cfe8 | 696 | arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; |
1da177e4 LT |
697 | } |
698 | ||
699 | /* Swap the send and the receive. */ | |
700 | rep.th.dest = th->source; | |
701 | rep.th.source = th->dest; | |
702 | rep.th.doff = arg.iov[0].iov_len / 4; | |
703 | rep.th.seq = htonl(seq); | |
704 | rep.th.ack_seq = htonl(ack); | |
705 | rep.th.ack = 1; | |
706 | rep.th.window = htons(win); | |
707 | ||
cfb6eeb4 | 708 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 YH |
709 | if (key) { |
710 | int offset = (ts) ? 3 : 0; | |
711 | ||
712 | rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | | |
713 | (TCPOPT_NOP << 16) | | |
714 | (TCPOPT_MD5SIG << 8) | | |
715 | TCPOLEN_MD5SIG); | |
716 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
717 | rep.th.doff = arg.iov[0].iov_len/4; | |
718 | ||
49a72dfb | 719 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset], |
90b7e112 AL |
720 | key, ip_hdr(skb)->saddr, |
721 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
722 | } |
723 | #endif | |
88ef4a5a | 724 | arg.flags = reply_flags; |
eddc9ec5 ACM |
725 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
726 | ip_hdr(skb)->saddr, /* XXX */ | |
1da177e4 LT |
727 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
728 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
9501f972 YH |
729 | if (oif) |
730 | arg.bound_dev_if = oif; | |
66b13d99 | 731 | arg.tos = tos; |
0a5ebb80 | 732 | ip_send_reply(net->ipv4.tcp_sock, skb, ip_hdr(skb)->saddr, |
7feb49c8 | 733 | &arg, arg.iov[0].iov_len); |
1da177e4 | 734 | |
63231bdd | 735 | TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); |
1da177e4 LT |
736 | } |
737 | ||
738 | static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) | |
739 | { | |
8feaf0c0 | 740 | struct inet_timewait_sock *tw = inet_twsk(sk); |
cfb6eeb4 | 741 | struct tcp_timewait_sock *tcptw = tcp_twsk(sk); |
1da177e4 | 742 | |
9501f972 | 743 | tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
7174259e | 744 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, |
9501f972 YH |
745 | tcptw->tw_ts_recent, |
746 | tw->tw_bound_dev_if, | |
88ef4a5a | 747 | tcp_twsk_md5_key(tcptw), |
66b13d99 ED |
748 | tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, |
749 | tw->tw_tos | |
9501f972 | 750 | ); |
1da177e4 | 751 | |
8feaf0c0 | 752 | inet_twsk_put(tw); |
1da177e4 LT |
753 | } |
754 | ||
6edafaaf | 755 | static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, |
7174259e | 756 | struct request_sock *req) |
1da177e4 | 757 | { |
9501f972 | 758 | tcp_v4_send_ack(skb, tcp_rsk(req)->snt_isn + 1, |
cfb6eeb4 | 759 | tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, |
9501f972 YH |
760 | req->ts_recent, |
761 | 0, | |
88ef4a5a | 762 | tcp_v4_md5_do_lookup(sk, ip_hdr(skb)->daddr), |
66b13d99 ED |
763 | inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, |
764 | ip_hdr(skb)->tos); | |
1da177e4 LT |
765 | } |
766 | ||
1da177e4 | 767 | /* |
9bf1d83e | 768 | * Send a SYN-ACK after having received a SYN. |
60236fdd | 769 | * This still operates on a request_sock only, not on a big |
1da177e4 LT |
770 | * socket. |
771 | */ | |
72659ecc OP |
772 | static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst, |
773 | struct request_sock *req, | |
774 | struct request_values *rvp) | |
1da177e4 | 775 | { |
2e6599cb | 776 | const struct inet_request_sock *ireq = inet_rsk(req); |
6bd023f3 | 777 | struct flowi4 fl4; |
1da177e4 LT |
778 | int err = -1; |
779 | struct sk_buff * skb; | |
780 | ||
781 | /* First, grab a route. */ | |
6bd023f3 | 782 | if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) |
fd80eb94 | 783 | return -1; |
1da177e4 | 784 | |
e6b4d113 | 785 | skb = tcp_make_synack(sk, dst, req, rvp); |
1da177e4 LT |
786 | |
787 | if (skb) { | |
419f9f89 | 788 | __tcp_v4_send_check(skb, ireq->loc_addr, ireq->rmt_addr); |
1da177e4 | 789 | |
2e6599cb ACM |
790 | err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, |
791 | ireq->rmt_addr, | |
792 | ireq->opt); | |
b9df3cb8 | 793 | err = net_xmit_eval(err); |
1da177e4 LT |
794 | } |
795 | ||
1da177e4 LT |
796 | dst_release(dst); |
797 | return err; | |
798 | } | |
799 | ||
72659ecc | 800 | static int tcp_v4_rtx_synack(struct sock *sk, struct request_sock *req, |
e6b4d113 | 801 | struct request_values *rvp) |
fd80eb94 | 802 | { |
72659ecc OP |
803 | TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS); |
804 | return tcp_v4_send_synack(sk, NULL, req, rvp); | |
fd80eb94 DL |
805 | } |
806 | ||
1da177e4 | 807 | /* |
60236fdd | 808 | * IPv4 request_sock destructor. |
1da177e4 | 809 | */ |
60236fdd | 810 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
1da177e4 | 811 | { |
a51482bd | 812 | kfree(inet_rsk(req)->opt); |
1da177e4 LT |
813 | } |
814 | ||
946cedcc ED |
815 | /* |
816 | * Return 1 if a syncookie should be sent | |
817 | */ | |
818 | int tcp_syn_flood_action(struct sock *sk, | |
819 | const struct sk_buff *skb, | |
820 | const char *proto) | |
1da177e4 | 821 | { |
946cedcc ED |
822 | const char *msg = "Dropping request"; |
823 | int want_cookie = 0; | |
824 | struct listen_sock *lopt; | |
825 | ||
826 | ||
1da177e4 | 827 | |
2a1d4bd4 | 828 | #ifdef CONFIG_SYN_COOKIES |
946cedcc | 829 | if (sysctl_tcp_syncookies) { |
2a1d4bd4 | 830 | msg = "Sending cookies"; |
946cedcc ED |
831 | want_cookie = 1; |
832 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES); | |
833 | } else | |
80e40daa | 834 | #endif |
946cedcc ED |
835 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP); |
836 | ||
837 | lopt = inet_csk(sk)->icsk_accept_queue.listen_opt; | |
838 | if (!lopt->synflood_warned) { | |
839 | lopt->synflood_warned = 1; | |
840 | pr_info("%s: Possible SYN flooding on port %d. %s. " | |
841 | " Check SNMP counters.\n", | |
842 | proto, ntohs(tcp_hdr(skb)->dest), msg); | |
843 | } | |
844 | return want_cookie; | |
2a1d4bd4 | 845 | } |
946cedcc | 846 | EXPORT_SYMBOL(tcp_syn_flood_action); |
1da177e4 LT |
847 | |
848 | /* | |
60236fdd | 849 | * Save and compile IPv4 options into the request_sock if needed. |
1da177e4 | 850 | */ |
f6d8bd05 ED |
851 | static struct ip_options_rcu *tcp_v4_save_options(struct sock *sk, |
852 | struct sk_buff *skb) | |
1da177e4 | 853 | { |
f6d8bd05 ED |
854 | const struct ip_options *opt = &(IPCB(skb)->opt); |
855 | struct ip_options_rcu *dopt = NULL; | |
1da177e4 LT |
856 | |
857 | if (opt && opt->optlen) { | |
f6d8bd05 ED |
858 | int opt_size = sizeof(*dopt) + opt->optlen; |
859 | ||
1da177e4 LT |
860 | dopt = kmalloc(opt_size, GFP_ATOMIC); |
861 | if (dopt) { | |
f6d8bd05 | 862 | if (ip_options_echo(&dopt->opt, skb)) { |
1da177e4 LT |
863 | kfree(dopt); |
864 | dopt = NULL; | |
865 | } | |
866 | } | |
867 | } | |
868 | return dopt; | |
869 | } | |
870 | ||
cfb6eeb4 YH |
871 | #ifdef CONFIG_TCP_MD5SIG |
872 | /* | |
873 | * RFC2385 MD5 checksumming requires a mapping of | |
874 | * IP address->MD5 Key. | |
875 | * We need to maintain these in the sk structure. | |
876 | */ | |
877 | ||
878 | /* Find the Key structure for an address. */ | |
7174259e ACM |
879 | static struct tcp_md5sig_key * |
880 | tcp_v4_md5_do_lookup(struct sock *sk, __be32 addr) | |
cfb6eeb4 YH |
881 | { |
882 | struct tcp_sock *tp = tcp_sk(sk); | |
883 | int i; | |
884 | ||
885 | if (!tp->md5sig_info || !tp->md5sig_info->entries4) | |
886 | return NULL; | |
887 | for (i = 0; i < tp->md5sig_info->entries4; i++) { | |
888 | if (tp->md5sig_info->keys4[i].addr == addr) | |
f8ab18d2 | 889 | return &tp->md5sig_info->keys4[i].base; |
cfb6eeb4 YH |
890 | } |
891 | return NULL; | |
892 | } | |
893 | ||
894 | struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk, | |
895 | struct sock *addr_sk) | |
896 | { | |
c720c7e8 | 897 | return tcp_v4_md5_do_lookup(sk, inet_sk(addr_sk)->inet_daddr); |
cfb6eeb4 | 898 | } |
cfb6eeb4 YH |
899 | EXPORT_SYMBOL(tcp_v4_md5_lookup); |
900 | ||
f5b99bcd AB |
901 | static struct tcp_md5sig_key *tcp_v4_reqsk_md5_lookup(struct sock *sk, |
902 | struct request_sock *req) | |
cfb6eeb4 YH |
903 | { |
904 | return tcp_v4_md5_do_lookup(sk, inet_rsk(req)->rmt_addr); | |
905 | } | |
906 | ||
907 | /* This can be called on a newly created socket, from other files */ | |
908 | int tcp_v4_md5_do_add(struct sock *sk, __be32 addr, | |
909 | u8 *newkey, u8 newkeylen) | |
910 | { | |
911 | /* Add Key to the list */ | |
b0a713e9 | 912 | struct tcp_md5sig_key *key; |
cfb6eeb4 YH |
913 | struct tcp_sock *tp = tcp_sk(sk); |
914 | struct tcp4_md5sig_key *keys; | |
915 | ||
b0a713e9 | 916 | key = tcp_v4_md5_do_lookup(sk, addr); |
cfb6eeb4 YH |
917 | if (key) { |
918 | /* Pre-existing entry - just update that one. */ | |
b0a713e9 MD |
919 | kfree(key->key); |
920 | key->key = newkey; | |
921 | key->keylen = newkeylen; | |
cfb6eeb4 | 922 | } else { |
f6685938 ACM |
923 | struct tcp_md5sig_info *md5sig; |
924 | ||
cfb6eeb4 | 925 | if (!tp->md5sig_info) { |
f6685938 ACM |
926 | tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), |
927 | GFP_ATOMIC); | |
cfb6eeb4 YH |
928 | if (!tp->md5sig_info) { |
929 | kfree(newkey); | |
930 | return -ENOMEM; | |
931 | } | |
a465419b | 932 | sk_nocaps_add(sk, NETIF_F_GSO_MASK); |
cfb6eeb4 | 933 | } |
260fcbeb YZ |
934 | |
935 | md5sig = tp->md5sig_info; | |
936 | if (md5sig->entries4 == 0 && | |
937 | tcp_alloc_md5sig_pool(sk) == NULL) { | |
cfb6eeb4 YH |
938 | kfree(newkey); |
939 | return -ENOMEM; | |
940 | } | |
f6685938 ACM |
941 | |
942 | if (md5sig->alloced4 == md5sig->entries4) { | |
943 | keys = kmalloc((sizeof(*keys) * | |
e905a9ed | 944 | (md5sig->entries4 + 1)), GFP_ATOMIC); |
cfb6eeb4 YH |
945 | if (!keys) { |
946 | kfree(newkey); | |
260fcbeb YZ |
947 | if (md5sig->entries4 == 0) |
948 | tcp_free_md5sig_pool(); | |
cfb6eeb4 YH |
949 | return -ENOMEM; |
950 | } | |
951 | ||
f6685938 ACM |
952 | if (md5sig->entries4) |
953 | memcpy(keys, md5sig->keys4, | |
954 | sizeof(*keys) * md5sig->entries4); | |
cfb6eeb4 YH |
955 | |
956 | /* Free old key list, and reference new one */ | |
a80cc20d | 957 | kfree(md5sig->keys4); |
f6685938 ACM |
958 | md5sig->keys4 = keys; |
959 | md5sig->alloced4++; | |
cfb6eeb4 | 960 | } |
f6685938 | 961 | md5sig->entries4++; |
f8ab18d2 DM |
962 | md5sig->keys4[md5sig->entries4 - 1].addr = addr; |
963 | md5sig->keys4[md5sig->entries4 - 1].base.key = newkey; | |
964 | md5sig->keys4[md5sig->entries4 - 1].base.keylen = newkeylen; | |
cfb6eeb4 YH |
965 | } |
966 | return 0; | |
967 | } | |
cfb6eeb4 YH |
968 | EXPORT_SYMBOL(tcp_v4_md5_do_add); |
969 | ||
970 | static int tcp_v4_md5_add_func(struct sock *sk, struct sock *addr_sk, | |
971 | u8 *newkey, u8 newkeylen) | |
972 | { | |
c720c7e8 | 973 | return tcp_v4_md5_do_add(sk, inet_sk(addr_sk)->inet_daddr, |
cfb6eeb4 YH |
974 | newkey, newkeylen); |
975 | } | |
976 | ||
977 | int tcp_v4_md5_do_del(struct sock *sk, __be32 addr) | |
978 | { | |
979 | struct tcp_sock *tp = tcp_sk(sk); | |
980 | int i; | |
981 | ||
982 | for (i = 0; i < tp->md5sig_info->entries4; i++) { | |
983 | if (tp->md5sig_info->keys4[i].addr == addr) { | |
984 | /* Free the key */ | |
f8ab18d2 | 985 | kfree(tp->md5sig_info->keys4[i].base.key); |
cfb6eeb4 YH |
986 | tp->md5sig_info->entries4--; |
987 | ||
988 | if (tp->md5sig_info->entries4 == 0) { | |
989 | kfree(tp->md5sig_info->keys4); | |
990 | tp->md5sig_info->keys4 = NULL; | |
8228a18d | 991 | tp->md5sig_info->alloced4 = 0; |
260fcbeb | 992 | tcp_free_md5sig_pool(); |
7174259e | 993 | } else if (tp->md5sig_info->entries4 != i) { |
cfb6eeb4 | 994 | /* Need to do some manipulation */ |
354faf09 YH |
995 | memmove(&tp->md5sig_info->keys4[i], |
996 | &tp->md5sig_info->keys4[i+1], | |
997 | (tp->md5sig_info->entries4 - i) * | |
998 | sizeof(struct tcp4_md5sig_key)); | |
cfb6eeb4 | 999 | } |
cfb6eeb4 YH |
1000 | return 0; |
1001 | } | |
1002 | } | |
1003 | return -ENOENT; | |
1004 | } | |
cfb6eeb4 YH |
1005 | EXPORT_SYMBOL(tcp_v4_md5_do_del); |
1006 | ||
7174259e | 1007 | static void tcp_v4_clear_md5_list(struct sock *sk) |
cfb6eeb4 YH |
1008 | { |
1009 | struct tcp_sock *tp = tcp_sk(sk); | |
1010 | ||
1011 | /* Free each key, then the set of key keys, | |
1012 | * the crypto element, and then decrement our | |
1013 | * hold on the last resort crypto. | |
1014 | */ | |
1015 | if (tp->md5sig_info->entries4) { | |
1016 | int i; | |
1017 | for (i = 0; i < tp->md5sig_info->entries4; i++) | |
f8ab18d2 | 1018 | kfree(tp->md5sig_info->keys4[i].base.key); |
cfb6eeb4 YH |
1019 | tp->md5sig_info->entries4 = 0; |
1020 | tcp_free_md5sig_pool(); | |
1021 | } | |
1022 | if (tp->md5sig_info->keys4) { | |
1023 | kfree(tp->md5sig_info->keys4); | |
1024 | tp->md5sig_info->keys4 = NULL; | |
1025 | tp->md5sig_info->alloced4 = 0; | |
1026 | } | |
1027 | } | |
1028 | ||
7174259e ACM |
1029 | static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval, |
1030 | int optlen) | |
cfb6eeb4 YH |
1031 | { |
1032 | struct tcp_md5sig cmd; | |
1033 | struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; | |
1034 | u8 *newkey; | |
1035 | ||
1036 | if (optlen < sizeof(cmd)) | |
1037 | return -EINVAL; | |
1038 | ||
7174259e | 1039 | if (copy_from_user(&cmd, optval, sizeof(cmd))) |
cfb6eeb4 YH |
1040 | return -EFAULT; |
1041 | ||
1042 | if (sin->sin_family != AF_INET) | |
1043 | return -EINVAL; | |
1044 | ||
1045 | if (!cmd.tcpm_key || !cmd.tcpm_keylen) { | |
1046 | if (!tcp_sk(sk)->md5sig_info) | |
1047 | return -ENOENT; | |
1048 | return tcp_v4_md5_do_del(sk, sin->sin_addr.s_addr); | |
1049 | } | |
1050 | ||
1051 | if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) | |
1052 | return -EINVAL; | |
1053 | ||
1054 | if (!tcp_sk(sk)->md5sig_info) { | |
1055 | struct tcp_sock *tp = tcp_sk(sk); | |
aa133076 | 1056 | struct tcp_md5sig_info *p; |
cfb6eeb4 | 1057 | |
aa133076 | 1058 | p = kzalloc(sizeof(*p), sk->sk_allocation); |
cfb6eeb4 YH |
1059 | if (!p) |
1060 | return -EINVAL; | |
1061 | ||
1062 | tp->md5sig_info = p; | |
a465419b | 1063 | sk_nocaps_add(sk, NETIF_F_GSO_MASK); |
cfb6eeb4 YH |
1064 | } |
1065 | ||
aa133076 | 1066 | newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, sk->sk_allocation); |
cfb6eeb4 YH |
1067 | if (!newkey) |
1068 | return -ENOMEM; | |
cfb6eeb4 YH |
1069 | return tcp_v4_md5_do_add(sk, sin->sin_addr.s_addr, |
1070 | newkey, cmd.tcpm_keylen); | |
1071 | } | |
1072 | ||
49a72dfb AL |
1073 | static int tcp_v4_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, |
1074 | __be32 daddr, __be32 saddr, int nbytes) | |
cfb6eeb4 | 1075 | { |
cfb6eeb4 | 1076 | struct tcp4_pseudohdr *bp; |
49a72dfb | 1077 | struct scatterlist sg; |
cfb6eeb4 YH |
1078 | |
1079 | bp = &hp->md5_blk.ip4; | |
cfb6eeb4 YH |
1080 | |
1081 | /* | |
49a72dfb | 1082 | * 1. the TCP pseudo-header (in the order: source IP address, |
cfb6eeb4 YH |
1083 | * destination IP address, zero-padded protocol number, and |
1084 | * segment length) | |
1085 | */ | |
1086 | bp->saddr = saddr; | |
1087 | bp->daddr = daddr; | |
1088 | bp->pad = 0; | |
076fb722 | 1089 | bp->protocol = IPPROTO_TCP; |
49a72dfb | 1090 | bp->len = cpu_to_be16(nbytes); |
c7da57a1 | 1091 | |
49a72dfb AL |
1092 | sg_init_one(&sg, bp, sizeof(*bp)); |
1093 | return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp)); | |
1094 | } | |
1095 | ||
1096 | static int tcp_v4_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, | |
318cf7aa | 1097 | __be32 daddr, __be32 saddr, const struct tcphdr *th) |
49a72dfb AL |
1098 | { |
1099 | struct tcp_md5sig_pool *hp; | |
1100 | struct hash_desc *desc; | |
1101 | ||
1102 | hp = tcp_get_md5sig_pool(); | |
1103 | if (!hp) | |
1104 | goto clear_hash_noput; | |
1105 | desc = &hp->md5_desc; | |
1106 | ||
1107 | if (crypto_hash_init(desc)) | |
1108 | goto clear_hash; | |
1109 | if (tcp_v4_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) | |
1110 | goto clear_hash; | |
1111 | if (tcp_md5_hash_header(hp, th)) | |
1112 | goto clear_hash; | |
1113 | if (tcp_md5_hash_key(hp, key)) | |
1114 | goto clear_hash; | |
1115 | if (crypto_hash_final(desc, md5_hash)) | |
cfb6eeb4 YH |
1116 | goto clear_hash; |
1117 | ||
cfb6eeb4 | 1118 | tcp_put_md5sig_pool(); |
cfb6eeb4 | 1119 | return 0; |
49a72dfb | 1120 | |
cfb6eeb4 YH |
1121 | clear_hash: |
1122 | tcp_put_md5sig_pool(); | |
1123 | clear_hash_noput: | |
1124 | memset(md5_hash, 0, 16); | |
49a72dfb | 1125 | return 1; |
cfb6eeb4 YH |
1126 | } |
1127 | ||
49a72dfb | 1128 | int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key, |
318cf7aa ED |
1129 | const struct sock *sk, const struct request_sock *req, |
1130 | const struct sk_buff *skb) | |
cfb6eeb4 | 1131 | { |
49a72dfb AL |
1132 | struct tcp_md5sig_pool *hp; |
1133 | struct hash_desc *desc; | |
318cf7aa | 1134 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
1135 | __be32 saddr, daddr; |
1136 | ||
1137 | if (sk) { | |
c720c7e8 ED |
1138 | saddr = inet_sk(sk)->inet_saddr; |
1139 | daddr = inet_sk(sk)->inet_daddr; | |
49a72dfb AL |
1140 | } else if (req) { |
1141 | saddr = inet_rsk(req)->loc_addr; | |
1142 | daddr = inet_rsk(req)->rmt_addr; | |
cfb6eeb4 | 1143 | } else { |
49a72dfb AL |
1144 | const struct iphdr *iph = ip_hdr(skb); |
1145 | saddr = iph->saddr; | |
1146 | daddr = iph->daddr; | |
cfb6eeb4 | 1147 | } |
49a72dfb AL |
1148 | |
1149 | hp = tcp_get_md5sig_pool(); | |
1150 | if (!hp) | |
1151 | goto clear_hash_noput; | |
1152 | desc = &hp->md5_desc; | |
1153 | ||
1154 | if (crypto_hash_init(desc)) | |
1155 | goto clear_hash; | |
1156 | ||
1157 | if (tcp_v4_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) | |
1158 | goto clear_hash; | |
1159 | if (tcp_md5_hash_header(hp, th)) | |
1160 | goto clear_hash; | |
1161 | if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) | |
1162 | goto clear_hash; | |
1163 | if (tcp_md5_hash_key(hp, key)) | |
1164 | goto clear_hash; | |
1165 | if (crypto_hash_final(desc, md5_hash)) | |
1166 | goto clear_hash; | |
1167 | ||
1168 | tcp_put_md5sig_pool(); | |
1169 | return 0; | |
1170 | ||
1171 | clear_hash: | |
1172 | tcp_put_md5sig_pool(); | |
1173 | clear_hash_noput: | |
1174 | memset(md5_hash, 0, 16); | |
1175 | return 1; | |
cfb6eeb4 | 1176 | } |
49a72dfb | 1177 | EXPORT_SYMBOL(tcp_v4_md5_hash_skb); |
cfb6eeb4 | 1178 | |
318cf7aa | 1179 | static int tcp_v4_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb) |
cfb6eeb4 YH |
1180 | { |
1181 | /* | |
1182 | * This gets called for each TCP segment that arrives | |
1183 | * so we want to be efficient. | |
1184 | * We have 3 drop cases: | |
1185 | * o No MD5 hash and one expected. | |
1186 | * o MD5 hash and we're not expecting one. | |
1187 | * o MD5 hash and its wrong. | |
1188 | */ | |
cf533ea5 | 1189 | const __u8 *hash_location = NULL; |
cfb6eeb4 | 1190 | struct tcp_md5sig_key *hash_expected; |
eddc9ec5 | 1191 | const struct iphdr *iph = ip_hdr(skb); |
cf533ea5 | 1192 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 | 1193 | int genhash; |
cfb6eeb4 YH |
1194 | unsigned char newhash[16]; |
1195 | ||
1196 | hash_expected = tcp_v4_md5_do_lookup(sk, iph->saddr); | |
7d5d5525 | 1197 | hash_location = tcp_parse_md5sig_option(th); |
cfb6eeb4 | 1198 | |
cfb6eeb4 YH |
1199 | /* We've parsed the options - do we have a hash? */ |
1200 | if (!hash_expected && !hash_location) | |
1201 | return 0; | |
1202 | ||
1203 | if (hash_expected && !hash_location) { | |
785957d3 | 1204 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); |
cfb6eeb4 YH |
1205 | return 1; |
1206 | } | |
1207 | ||
1208 | if (!hash_expected && hash_location) { | |
785957d3 | 1209 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); |
cfb6eeb4 YH |
1210 | return 1; |
1211 | } | |
1212 | ||
1213 | /* Okay, so this is hash_expected and hash_location - | |
1214 | * so we need to calculate the checksum. | |
1215 | */ | |
49a72dfb AL |
1216 | genhash = tcp_v4_md5_hash_skb(newhash, |
1217 | hash_expected, | |
1218 | NULL, NULL, skb); | |
cfb6eeb4 YH |
1219 | |
1220 | if (genhash || memcmp(hash_location, newhash, 16) != 0) { | |
1221 | if (net_ratelimit()) { | |
673d57e7 HH |
1222 | printk(KERN_INFO "MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n", |
1223 | &iph->saddr, ntohs(th->source), | |
1224 | &iph->daddr, ntohs(th->dest), | |
cfb6eeb4 | 1225 | genhash ? " tcp_v4_calc_md5_hash failed" : ""); |
cfb6eeb4 YH |
1226 | } |
1227 | return 1; | |
1228 | } | |
1229 | return 0; | |
1230 | } | |
1231 | ||
1232 | #endif | |
1233 | ||
72a3effa | 1234 | struct request_sock_ops tcp_request_sock_ops __read_mostly = { |
1da177e4 | 1235 | .family = PF_INET, |
2e6599cb | 1236 | .obj_size = sizeof(struct tcp_request_sock), |
72659ecc | 1237 | .rtx_syn_ack = tcp_v4_rtx_synack, |
60236fdd ACM |
1238 | .send_ack = tcp_v4_reqsk_send_ack, |
1239 | .destructor = tcp_v4_reqsk_destructor, | |
1da177e4 | 1240 | .send_reset = tcp_v4_send_reset, |
72659ecc | 1241 | .syn_ack_timeout = tcp_syn_ack_timeout, |
1da177e4 LT |
1242 | }; |
1243 | ||
cfb6eeb4 | 1244 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 1245 | static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { |
cfb6eeb4 | 1246 | .md5_lookup = tcp_v4_reqsk_md5_lookup, |
e3afe7b7 | 1247 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 | 1248 | }; |
b6332e6c | 1249 | #endif |
cfb6eeb4 | 1250 | |
1da177e4 LT |
1251 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
1252 | { | |
4957faad | 1253 | struct tcp_extend_values tmp_ext; |
1da177e4 | 1254 | struct tcp_options_received tmp_opt; |
cf533ea5 | 1255 | const u8 *hash_location; |
60236fdd | 1256 | struct request_sock *req; |
e6b4d113 | 1257 | struct inet_request_sock *ireq; |
4957faad | 1258 | struct tcp_sock *tp = tcp_sk(sk); |
e6b4d113 | 1259 | struct dst_entry *dst = NULL; |
eddc9ec5 ACM |
1260 | __be32 saddr = ip_hdr(skb)->saddr; |
1261 | __be32 daddr = ip_hdr(skb)->daddr; | |
1da177e4 | 1262 | __u32 isn = TCP_SKB_CB(skb)->when; |
1da177e4 | 1263 | int want_cookie = 0; |
1da177e4 LT |
1264 | |
1265 | /* Never answer to SYNs send to broadcast or multicast */ | |
511c3f92 | 1266 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
1da177e4 LT |
1267 | goto drop; |
1268 | ||
1269 | /* TW buckets are converted to open requests without | |
1270 | * limitations, they conserve resources and peer is | |
1271 | * evidently real one. | |
1272 | */ | |
463c84b9 | 1273 | if (inet_csk_reqsk_queue_is_full(sk) && !isn) { |
946cedcc ED |
1274 | want_cookie = tcp_syn_flood_action(sk, skb, "TCP"); |
1275 | if (!want_cookie) | |
1276 | goto drop; | |
1da177e4 LT |
1277 | } |
1278 | ||
1279 | /* Accept backlog is full. If we have already queued enough | |
1280 | * of warm entries in syn queue, drop request. It is better than | |
1281 | * clogging syn queue with openreqs with exponentially increasing | |
1282 | * timeout. | |
1283 | */ | |
463c84b9 | 1284 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
1da177e4 LT |
1285 | goto drop; |
1286 | ||
ce4a7d0d | 1287 | req = inet_reqsk_alloc(&tcp_request_sock_ops); |
1da177e4 LT |
1288 | if (!req) |
1289 | goto drop; | |
1290 | ||
cfb6eeb4 YH |
1291 | #ifdef CONFIG_TCP_MD5SIG |
1292 | tcp_rsk(req)->af_specific = &tcp_request_sock_ipv4_ops; | |
1293 | #endif | |
1294 | ||
1da177e4 | 1295 | tcp_clear_options(&tmp_opt); |
bee7ca9e | 1296 | tmp_opt.mss_clamp = TCP_MSS_DEFAULT; |
4957faad | 1297 | tmp_opt.user_mss = tp->rx_opt.user_mss; |
bb5b7c11 | 1298 | tcp_parse_options(skb, &tmp_opt, &hash_location, 0); |
4957faad WAS |
1299 | |
1300 | if (tmp_opt.cookie_plus > 0 && | |
1301 | tmp_opt.saw_tstamp && | |
1302 | !tp->rx_opt.cookie_out_never && | |
1303 | (sysctl_tcp_cookie_size > 0 || | |
1304 | (tp->cookie_values != NULL && | |
1305 | tp->cookie_values->cookie_desired > 0))) { | |
1306 | u8 *c; | |
1307 | u32 *mess = &tmp_ext.cookie_bakery[COOKIE_DIGEST_WORDS]; | |
1308 | int l = tmp_opt.cookie_plus - TCPOLEN_COOKIE_BASE; | |
1309 | ||
1310 | if (tcp_cookie_generator(&tmp_ext.cookie_bakery[0]) != 0) | |
1311 | goto drop_and_release; | |
1312 | ||
1313 | /* Secret recipe starts with IP addresses */ | |
0eae88f3 ED |
1314 | *mess++ ^= (__force u32)daddr; |
1315 | *mess++ ^= (__force u32)saddr; | |
1da177e4 | 1316 | |
4957faad WAS |
1317 | /* plus variable length Initiator Cookie */ |
1318 | c = (u8 *)mess; | |
1319 | while (l-- > 0) | |
1320 | *c++ ^= *hash_location++; | |
1321 | ||
4957faad | 1322 | want_cookie = 0; /* not our kind of cookie */ |
4957faad WAS |
1323 | tmp_ext.cookie_out_never = 0; /* false */ |
1324 | tmp_ext.cookie_plus = tmp_opt.cookie_plus; | |
1325 | } else if (!tp->rx_opt.cookie_in_always) { | |
1326 | /* redundant indications, but ensure initialization. */ | |
1327 | tmp_ext.cookie_out_never = 1; /* true */ | |
1328 | tmp_ext.cookie_plus = 0; | |
1329 | } else { | |
1330 | goto drop_and_release; | |
1331 | } | |
1332 | tmp_ext.cookie_in_always = tp->rx_opt.cookie_in_always; | |
1da177e4 | 1333 | |
4dfc2817 | 1334 | if (want_cookie && !tmp_opt.saw_tstamp) |
1da177e4 | 1335 | tcp_clear_options(&tmp_opt); |
1da177e4 | 1336 | |
1da177e4 | 1337 | tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; |
1da177e4 LT |
1338 | tcp_openreq_init(req, &tmp_opt, skb); |
1339 | ||
bb5b7c11 DM |
1340 | ireq = inet_rsk(req); |
1341 | ireq->loc_addr = daddr; | |
1342 | ireq->rmt_addr = saddr; | |
1343 | ireq->no_srccheck = inet_sk(sk)->transparent; | |
1344 | ireq->opt = tcp_v4_save_options(sk, skb); | |
1345 | ||
284904aa | 1346 | if (security_inet_conn_request(sk, skb, req)) |
bb5b7c11 | 1347 | goto drop_and_free; |
284904aa | 1348 | |
172d69e6 | 1349 | if (!want_cookie || tmp_opt.tstamp_ok) |
aa8223c7 | 1350 | TCP_ECN_create_request(req, tcp_hdr(skb)); |
1da177e4 LT |
1351 | |
1352 | if (want_cookie) { | |
1da177e4 | 1353 | isn = cookie_v4_init_sequence(sk, skb, &req->mss); |
172d69e6 | 1354 | req->cookie_ts = tmp_opt.tstamp_ok; |
1da177e4 LT |
1355 | } else if (!isn) { |
1356 | struct inet_peer *peer = NULL; | |
6bd023f3 | 1357 | struct flowi4 fl4; |
1da177e4 LT |
1358 | |
1359 | /* VJ's idea. We save last timestamp seen | |
1360 | * from the destination in peer table, when entering | |
1361 | * state TIME-WAIT, and check against it before | |
1362 | * accepting new connection request. | |
1363 | * | |
1364 | * If "isn" is not zero, this request hit alive | |
1365 | * timewait bucket, so that all the necessary checks | |
1366 | * are made in the function processing timewait state. | |
1367 | */ | |
1368 | if (tmp_opt.saw_tstamp && | |
295ff7ed | 1369 | tcp_death_row.sysctl_tw_recycle && |
6bd023f3 | 1370 | (dst = inet_csk_route_req(sk, &fl4, req)) != NULL && |
ed2361e6 DM |
1371 | fl4.daddr == saddr && |
1372 | (peer = rt_get_peer((struct rtable *)dst, fl4.daddr)) != NULL) { | |
317fe0e6 | 1373 | inet_peer_refcheck(peer); |
2c1409a0 | 1374 | if ((u32)get_seconds() - peer->tcp_ts_stamp < TCP_PAWS_MSL && |
1da177e4 LT |
1375 | (s32)(peer->tcp_ts - req->ts_recent) > |
1376 | TCP_PAWS_WINDOW) { | |
de0744af | 1377 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED); |
7cd04fa7 | 1378 | goto drop_and_release; |
1da177e4 LT |
1379 | } |
1380 | } | |
1381 | /* Kill the following clause, if you dislike this way. */ | |
1382 | else if (!sysctl_tcp_syncookies && | |
463c84b9 | 1383 | (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) < |
1da177e4 LT |
1384 | (sysctl_max_syn_backlog >> 2)) && |
1385 | (!peer || !peer->tcp_ts_stamp) && | |
1386 | (!dst || !dst_metric(dst, RTAX_RTT))) { | |
1387 | /* Without syncookies last quarter of | |
1388 | * backlog is filled with destinations, | |
1389 | * proven to be alive. | |
1390 | * It means that we continue to communicate | |
1391 | * to destinations, already remembered | |
1392 | * to the moment of synflood. | |
1393 | */ | |
673d57e7 HH |
1394 | LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open request from %pI4/%u\n", |
1395 | &saddr, ntohs(tcp_hdr(skb)->source)); | |
7cd04fa7 | 1396 | goto drop_and_release; |
1da177e4 LT |
1397 | } |
1398 | ||
a94f723d | 1399 | isn = tcp_v4_init_sequence(skb); |
1da177e4 | 1400 | } |
2e6599cb | 1401 | tcp_rsk(req)->snt_isn = isn; |
9ad7c049 | 1402 | tcp_rsk(req)->snt_synack = tcp_time_stamp; |
1da177e4 | 1403 | |
72659ecc OP |
1404 | if (tcp_v4_send_synack(sk, dst, req, |
1405 | (struct request_values *)&tmp_ext) || | |
4957faad | 1406 | want_cookie) |
1da177e4 LT |
1407 | goto drop_and_free; |
1408 | ||
7cd04fa7 | 1409 | inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); |
1da177e4 LT |
1410 | return 0; |
1411 | ||
7cd04fa7 DL |
1412 | drop_and_release: |
1413 | dst_release(dst); | |
1da177e4 | 1414 | drop_and_free: |
60236fdd | 1415 | reqsk_free(req); |
1da177e4 | 1416 | drop: |
1da177e4 LT |
1417 | return 0; |
1418 | } | |
4bc2f18b | 1419 | EXPORT_SYMBOL(tcp_v4_conn_request); |
1da177e4 LT |
1420 | |
1421 | ||
1422 | /* | |
1423 | * The three way handshake has completed - we got a valid synack - | |
1424 | * now create the new socket. | |
1425 | */ | |
1426 | struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, | |
60236fdd | 1427 | struct request_sock *req, |
1da177e4 LT |
1428 | struct dst_entry *dst) |
1429 | { | |
2e6599cb | 1430 | struct inet_request_sock *ireq; |
1da177e4 LT |
1431 | struct inet_sock *newinet; |
1432 | struct tcp_sock *newtp; | |
1433 | struct sock *newsk; | |
cfb6eeb4 YH |
1434 | #ifdef CONFIG_TCP_MD5SIG |
1435 | struct tcp_md5sig_key *key; | |
1436 | #endif | |
f6d8bd05 | 1437 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
1438 | |
1439 | if (sk_acceptq_is_full(sk)) | |
1440 | goto exit_overflow; | |
1441 | ||
1da177e4 LT |
1442 | newsk = tcp_create_openreq_child(sk, req, skb); |
1443 | if (!newsk) | |
093d2823 | 1444 | goto exit_nonewsk; |
1da177e4 | 1445 | |
bcd76111 | 1446 | newsk->sk_gso_type = SKB_GSO_TCPV4; |
1da177e4 LT |
1447 | |
1448 | newtp = tcp_sk(newsk); | |
1449 | newinet = inet_sk(newsk); | |
2e6599cb | 1450 | ireq = inet_rsk(req); |
c720c7e8 ED |
1451 | newinet->inet_daddr = ireq->rmt_addr; |
1452 | newinet->inet_rcv_saddr = ireq->loc_addr; | |
1453 | newinet->inet_saddr = ireq->loc_addr; | |
f6d8bd05 ED |
1454 | inet_opt = ireq->opt; |
1455 | rcu_assign_pointer(newinet->inet_opt, inet_opt); | |
2e6599cb | 1456 | ireq->opt = NULL; |
463c84b9 | 1457 | newinet->mc_index = inet_iif(skb); |
eddc9ec5 | 1458 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
d83d8461 | 1459 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
1460 | if (inet_opt) |
1461 | inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
c720c7e8 | 1462 | newinet->inet_id = newtp->write_seq ^ jiffies; |
1da177e4 | 1463 | |
0e734419 DM |
1464 | if (!dst && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) |
1465 | goto put_and_exit; | |
1466 | ||
1467 | sk_setup_caps(newsk, dst); | |
1468 | ||
5d424d5a | 1469 | tcp_mtup_init(newsk); |
1da177e4 | 1470 | tcp_sync_mss(newsk, dst_mtu(dst)); |
0dbaee3b | 1471 | newtp->advmss = dst_metric_advmss(dst); |
f5fff5dc TQ |
1472 | if (tcp_sk(sk)->rx_opt.user_mss && |
1473 | tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) | |
1474 | newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; | |
1475 | ||
1da177e4 | 1476 | tcp_initialize_rcv_mss(newsk); |
9ad7c049 JC |
1477 | if (tcp_rsk(req)->snt_synack) |
1478 | tcp_valid_rtt_meas(newsk, | |
1479 | tcp_time_stamp - tcp_rsk(req)->snt_synack); | |
1480 | newtp->total_retrans = req->retrans; | |
1da177e4 | 1481 | |
cfb6eeb4 YH |
1482 | #ifdef CONFIG_TCP_MD5SIG |
1483 | /* Copy over the MD5 key from the original socket */ | |
c720c7e8 ED |
1484 | key = tcp_v4_md5_do_lookup(sk, newinet->inet_daddr); |
1485 | if (key != NULL) { | |
cfb6eeb4 YH |
1486 | /* |
1487 | * We're using one, so create a matching key | |
1488 | * on the newsk structure. If we fail to get | |
1489 | * memory, then we end up not copying the key | |
1490 | * across. Shucks. | |
1491 | */ | |
f6685938 ACM |
1492 | char *newkey = kmemdup(key->key, key->keylen, GFP_ATOMIC); |
1493 | if (newkey != NULL) | |
c720c7e8 | 1494 | tcp_v4_md5_do_add(newsk, newinet->inet_daddr, |
cfb6eeb4 | 1495 | newkey, key->keylen); |
a465419b | 1496 | sk_nocaps_add(newsk, NETIF_F_GSO_MASK); |
cfb6eeb4 YH |
1497 | } |
1498 | #endif | |
1499 | ||
0e734419 DM |
1500 | if (__inet_inherit_port(sk, newsk) < 0) |
1501 | goto put_and_exit; | |
9327f705 | 1502 | __inet_hash_nolisten(newsk, NULL); |
1da177e4 LT |
1503 | |
1504 | return newsk; | |
1505 | ||
1506 | exit_overflow: | |
de0744af | 1507 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
093d2823 BS |
1508 | exit_nonewsk: |
1509 | dst_release(dst); | |
1da177e4 | 1510 | exit: |
de0744af | 1511 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); |
1da177e4 | 1512 | return NULL; |
0e734419 | 1513 | put_and_exit: |
709e8697 | 1514 | tcp_clear_xmit_timers(newsk); |
d8a6e65f | 1515 | tcp_cleanup_congestion_control(newsk); |
918eb399 | 1516 | bh_unlock_sock(newsk); |
0e734419 DM |
1517 | sock_put(newsk); |
1518 | goto exit; | |
1da177e4 | 1519 | } |
4bc2f18b | 1520 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); |
1da177e4 LT |
1521 | |
1522 | static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) | |
1523 | { | |
aa8223c7 | 1524 | struct tcphdr *th = tcp_hdr(skb); |
eddc9ec5 | 1525 | const struct iphdr *iph = ip_hdr(skb); |
1da177e4 | 1526 | struct sock *nsk; |
60236fdd | 1527 | struct request_sock **prev; |
1da177e4 | 1528 | /* Find possible connection requests. */ |
463c84b9 ACM |
1529 | struct request_sock *req = inet_csk_search_req(sk, &prev, th->source, |
1530 | iph->saddr, iph->daddr); | |
1da177e4 LT |
1531 | if (req) |
1532 | return tcp_check_req(sk, skb, req, prev); | |
1533 | ||
3b1e0a65 | 1534 | nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr, |
c67499c0 | 1535 | th->source, iph->daddr, th->dest, inet_iif(skb)); |
1da177e4 LT |
1536 | |
1537 | if (nsk) { | |
1538 | if (nsk->sk_state != TCP_TIME_WAIT) { | |
1539 | bh_lock_sock(nsk); | |
1540 | return nsk; | |
1541 | } | |
9469c7b4 | 1542 | inet_twsk_put(inet_twsk(nsk)); |
1da177e4 LT |
1543 | return NULL; |
1544 | } | |
1545 | ||
1546 | #ifdef CONFIG_SYN_COOKIES | |
af9b4738 | 1547 | if (!th->syn) |
1da177e4 LT |
1548 | sk = cookie_v4_check(sk, skb, &(IPCB(skb)->opt)); |
1549 | #endif | |
1550 | return sk; | |
1551 | } | |
1552 | ||
b51655b9 | 1553 | static __sum16 tcp_v4_checksum_init(struct sk_buff *skb) |
1da177e4 | 1554 | { |
eddc9ec5 ACM |
1555 | const struct iphdr *iph = ip_hdr(skb); |
1556 | ||
84fa7933 | 1557 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
eddc9ec5 ACM |
1558 | if (!tcp_v4_check(skb->len, iph->saddr, |
1559 | iph->daddr, skb->csum)) { | |
fb286bb2 | 1560 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
1da177e4 | 1561 | return 0; |
fb286bb2 | 1562 | } |
1da177e4 | 1563 | } |
fb286bb2 | 1564 | |
eddc9ec5 | 1565 | skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, |
fb286bb2 HX |
1566 | skb->len, IPPROTO_TCP, 0); |
1567 | ||
1da177e4 | 1568 | if (skb->len <= 76) { |
fb286bb2 | 1569 | return __skb_checksum_complete(skb); |
1da177e4 LT |
1570 | } |
1571 | return 0; | |
1572 | } | |
1573 | ||
1574 | ||
1575 | /* The socket must have it's spinlock held when we get | |
1576 | * here. | |
1577 | * | |
1578 | * We have a potential double-lock case here, so even when | |
1579 | * doing backlog processing we use the BH locking scheme. | |
1580 | * This is because we cannot sleep with the original spinlock | |
1581 | * held. | |
1582 | */ | |
1583 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) | |
1584 | { | |
cfb6eeb4 YH |
1585 | struct sock *rsk; |
1586 | #ifdef CONFIG_TCP_MD5SIG | |
1587 | /* | |
1588 | * We really want to reject the packet as early as possible | |
1589 | * if: | |
1590 | * o We're expecting an MD5'd packet and this is no MD5 tcp option | |
1591 | * o There is an MD5 option and we're not expecting one | |
1592 | */ | |
7174259e | 1593 | if (tcp_v4_inbound_md5_hash(sk, skb)) |
cfb6eeb4 YH |
1594 | goto discard; |
1595 | #endif | |
1596 | ||
1da177e4 | 1597 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
bdeab991 | 1598 | sock_rps_save_rxhash(sk, skb); |
aa8223c7 | 1599 | if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) { |
cfb6eeb4 | 1600 | rsk = sk; |
1da177e4 | 1601 | goto reset; |
cfb6eeb4 | 1602 | } |
1da177e4 LT |
1603 | return 0; |
1604 | } | |
1605 | ||
ab6a5bb6 | 1606 | if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb)) |
1da177e4 LT |
1607 | goto csum_err; |
1608 | ||
1609 | if (sk->sk_state == TCP_LISTEN) { | |
1610 | struct sock *nsk = tcp_v4_hnd_req(sk, skb); | |
1611 | if (!nsk) | |
1612 | goto discard; | |
1613 | ||
1614 | if (nsk != sk) { | |
bdeab991 | 1615 | sock_rps_save_rxhash(nsk, skb); |
cfb6eeb4 YH |
1616 | if (tcp_child_process(sk, nsk, skb)) { |
1617 | rsk = nsk; | |
1da177e4 | 1618 | goto reset; |
cfb6eeb4 | 1619 | } |
1da177e4 LT |
1620 | return 0; |
1621 | } | |
ca55158c | 1622 | } else |
bdeab991 | 1623 | sock_rps_save_rxhash(sk, skb); |
ca55158c | 1624 | |
aa8223c7 | 1625 | if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) { |
cfb6eeb4 | 1626 | rsk = sk; |
1da177e4 | 1627 | goto reset; |
cfb6eeb4 | 1628 | } |
1da177e4 LT |
1629 | return 0; |
1630 | ||
1631 | reset: | |
cfb6eeb4 | 1632 | tcp_v4_send_reset(rsk, skb); |
1da177e4 LT |
1633 | discard: |
1634 | kfree_skb(skb); | |
1635 | /* Be careful here. If this function gets more complicated and | |
1636 | * gcc suffers from register pressure on the x86, sk (in %ebx) | |
1637 | * might be destroyed here. This current version compiles correctly, | |
1638 | * but you have been warned. | |
1639 | */ | |
1640 | return 0; | |
1641 | ||
1642 | csum_err: | |
63231bdd | 1643 | TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); |
1da177e4 LT |
1644 | goto discard; |
1645 | } | |
4bc2f18b | 1646 | EXPORT_SYMBOL(tcp_v4_do_rcv); |
1da177e4 LT |
1647 | |
1648 | /* | |
1649 | * From tcp_input.c | |
1650 | */ | |
1651 | ||
1652 | int tcp_v4_rcv(struct sk_buff *skb) | |
1653 | { | |
eddc9ec5 | 1654 | const struct iphdr *iph; |
cf533ea5 | 1655 | const struct tcphdr *th; |
1da177e4 LT |
1656 | struct sock *sk; |
1657 | int ret; | |
a86b1e30 | 1658 | struct net *net = dev_net(skb->dev); |
1da177e4 LT |
1659 | |
1660 | if (skb->pkt_type != PACKET_HOST) | |
1661 | goto discard_it; | |
1662 | ||
1663 | /* Count it even if it's bad */ | |
63231bdd | 1664 | TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); |
1da177e4 LT |
1665 | |
1666 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | |
1667 | goto discard_it; | |
1668 | ||
aa8223c7 | 1669 | th = tcp_hdr(skb); |
1da177e4 LT |
1670 | |
1671 | if (th->doff < sizeof(struct tcphdr) / 4) | |
1672 | goto bad_packet; | |
1673 | if (!pskb_may_pull(skb, th->doff * 4)) | |
1674 | goto discard_it; | |
1675 | ||
1676 | /* An explanation is required here, I think. | |
1677 | * Packet length and doff are validated by header prediction, | |
caa20d9a | 1678 | * provided case of th->doff==0 is eliminated. |
1da177e4 | 1679 | * So, we defer the checks. */ |
60476372 | 1680 | if (!skb_csum_unnecessary(skb) && tcp_v4_checksum_init(skb)) |
1da177e4 LT |
1681 | goto bad_packet; |
1682 | ||
aa8223c7 | 1683 | th = tcp_hdr(skb); |
eddc9ec5 | 1684 | iph = ip_hdr(skb); |
1da177e4 LT |
1685 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); |
1686 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | |
1687 | skb->len - th->doff * 4); | |
1688 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | |
1689 | TCP_SKB_CB(skb)->when = 0; | |
b82d1bb4 | 1690 | TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); |
1da177e4 LT |
1691 | TCP_SKB_CB(skb)->sacked = 0; |
1692 | ||
9a1f27c4 | 1693 | sk = __inet_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest); |
1da177e4 LT |
1694 | if (!sk) |
1695 | goto no_tcp_socket; | |
1696 | ||
bb134d5d ED |
1697 | process: |
1698 | if (sk->sk_state == TCP_TIME_WAIT) | |
1699 | goto do_time_wait; | |
1700 | ||
6cce09f8 ED |
1701 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
1702 | NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); | |
d218d111 | 1703 | goto discard_and_relse; |
6cce09f8 | 1704 | } |
d218d111 | 1705 | |
1da177e4 LT |
1706 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
1707 | goto discard_and_relse; | |
b59c2701 | 1708 | nf_reset(skb); |
1da177e4 | 1709 | |
fda9ef5d | 1710 | if (sk_filter(sk, skb)) |
1da177e4 LT |
1711 | goto discard_and_relse; |
1712 | ||
1713 | skb->dev = NULL; | |
1714 | ||
c6366184 | 1715 | bh_lock_sock_nested(sk); |
1da177e4 LT |
1716 | ret = 0; |
1717 | if (!sock_owned_by_user(sk)) { | |
1a2449a8 CL |
1718 | #ifdef CONFIG_NET_DMA |
1719 | struct tcp_sock *tp = tcp_sk(sk); | |
1720 | if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) | |
f67b4599 | 1721 | tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY); |
1a2449a8 | 1722 | if (tp->ucopy.dma_chan) |
1da177e4 | 1723 | ret = tcp_v4_do_rcv(sk, skb); |
1a2449a8 CL |
1724 | else |
1725 | #endif | |
1726 | { | |
1727 | if (!tcp_prequeue(sk, skb)) | |
ae8d7f88 | 1728 | ret = tcp_v4_do_rcv(sk, skb); |
1a2449a8 | 1729 | } |
6cce09f8 | 1730 | } else if (unlikely(sk_add_backlog(sk, skb))) { |
6b03a53a | 1731 | bh_unlock_sock(sk); |
6cce09f8 | 1732 | NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); |
6b03a53a ZY |
1733 | goto discard_and_relse; |
1734 | } | |
1da177e4 LT |
1735 | bh_unlock_sock(sk); |
1736 | ||
1737 | sock_put(sk); | |
1738 | ||
1739 | return ret; | |
1740 | ||
1741 | no_tcp_socket: | |
1742 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) | |
1743 | goto discard_it; | |
1744 | ||
1745 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { | |
1746 | bad_packet: | |
63231bdd | 1747 | TCP_INC_STATS_BH(net, TCP_MIB_INERRS); |
1da177e4 | 1748 | } else { |
cfb6eeb4 | 1749 | tcp_v4_send_reset(NULL, skb); |
1da177e4 LT |
1750 | } |
1751 | ||
1752 | discard_it: | |
1753 | /* Discard frame. */ | |
1754 | kfree_skb(skb); | |
e905a9ed | 1755 | return 0; |
1da177e4 LT |
1756 | |
1757 | discard_and_relse: | |
1758 | sock_put(sk); | |
1759 | goto discard_it; | |
1760 | ||
1761 | do_time_wait: | |
1762 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | |
9469c7b4 | 1763 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
1764 | goto discard_it; |
1765 | } | |
1766 | ||
1767 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { | |
63231bdd | 1768 | TCP_INC_STATS_BH(net, TCP_MIB_INERRS); |
9469c7b4 | 1769 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
1770 | goto discard_it; |
1771 | } | |
9469c7b4 | 1772 | switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { |
1da177e4 | 1773 | case TCP_TW_SYN: { |
c346dca1 | 1774 | struct sock *sk2 = inet_lookup_listener(dev_net(skb->dev), |
c67499c0 | 1775 | &tcp_hashinfo, |
eddc9ec5 | 1776 | iph->daddr, th->dest, |
463c84b9 | 1777 | inet_iif(skb)); |
1da177e4 | 1778 | if (sk2) { |
9469c7b4 YH |
1779 | inet_twsk_deschedule(inet_twsk(sk), &tcp_death_row); |
1780 | inet_twsk_put(inet_twsk(sk)); | |
1da177e4 LT |
1781 | sk = sk2; |
1782 | goto process; | |
1783 | } | |
1784 | /* Fall through to ACK */ | |
1785 | } | |
1786 | case TCP_TW_ACK: | |
1787 | tcp_v4_timewait_ack(sk, skb); | |
1788 | break; | |
1789 | case TCP_TW_RST: | |
1790 | goto no_tcp_socket; | |
1791 | case TCP_TW_SUCCESS:; | |
1792 | } | |
1793 | goto discard_it; | |
1794 | } | |
1795 | ||
3f419d2d | 1796 | struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it) |
1da177e4 | 1797 | { |
3f419d2d | 1798 | struct rtable *rt = (struct rtable *) __sk_dst_get(sk); |
1da177e4 | 1799 | struct inet_sock *inet = inet_sk(sk); |
3f419d2d | 1800 | struct inet_peer *peer; |
1da177e4 | 1801 | |
c5216cc7 DM |
1802 | if (!rt || |
1803 | inet->cork.fl.u.ip4.daddr != inet->inet_daddr) { | |
b534ecf1 | 1804 | peer = inet_getpeer_v4(inet->inet_daddr, 1); |
3f419d2d | 1805 | *release_it = true; |
1da177e4 LT |
1806 | } else { |
1807 | if (!rt->peer) | |
a48eff12 | 1808 | rt_bind_peer(rt, inet->inet_daddr, 1); |
1da177e4 | 1809 | peer = rt->peer; |
3f419d2d | 1810 | *release_it = false; |
1da177e4 LT |
1811 | } |
1812 | ||
3f419d2d | 1813 | return peer; |
1da177e4 | 1814 | } |
3f419d2d | 1815 | EXPORT_SYMBOL(tcp_v4_get_peer); |
1da177e4 | 1816 | |
ccb7c410 | 1817 | void *tcp_v4_tw_get_peer(struct sock *sk) |
1da177e4 | 1818 | { |
cf533ea5 | 1819 | const struct inet_timewait_sock *tw = inet_twsk(sk); |
1da177e4 | 1820 | |
ccb7c410 | 1821 | return inet_getpeer_v4(tw->tw_daddr, 1); |
1da177e4 | 1822 | } |
ccb7c410 DM |
1823 | EXPORT_SYMBOL(tcp_v4_tw_get_peer); |
1824 | ||
1825 | static struct timewait_sock_ops tcp_timewait_sock_ops = { | |
1826 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), | |
1827 | .twsk_unique = tcp_twsk_unique, | |
1828 | .twsk_destructor= tcp_twsk_destructor, | |
1829 | .twsk_getpeer = tcp_v4_tw_get_peer, | |
1830 | }; | |
1da177e4 | 1831 | |
3b401a81 | 1832 | const struct inet_connection_sock_af_ops ipv4_specific = { |
543d9cfe ACM |
1833 | .queue_xmit = ip_queue_xmit, |
1834 | .send_check = tcp_v4_send_check, | |
1835 | .rebuild_header = inet_sk_rebuild_header, | |
1836 | .conn_request = tcp_v4_conn_request, | |
1837 | .syn_recv_sock = tcp_v4_syn_recv_sock, | |
3f419d2d | 1838 | .get_peer = tcp_v4_get_peer, |
543d9cfe ACM |
1839 | .net_header_len = sizeof(struct iphdr), |
1840 | .setsockopt = ip_setsockopt, | |
1841 | .getsockopt = ip_getsockopt, | |
1842 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
1843 | .sockaddr_len = sizeof(struct sockaddr_in), | |
ab1e0a13 | 1844 | .bind_conflict = inet_csk_bind_conflict, |
3fdadf7d | 1845 | #ifdef CONFIG_COMPAT |
543d9cfe ACM |
1846 | .compat_setsockopt = compat_ip_setsockopt, |
1847 | .compat_getsockopt = compat_ip_getsockopt, | |
3fdadf7d | 1848 | #endif |
1da177e4 | 1849 | }; |
4bc2f18b | 1850 | EXPORT_SYMBOL(ipv4_specific); |
1da177e4 | 1851 | |
cfb6eeb4 | 1852 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 1853 | static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = { |
cfb6eeb4 | 1854 | .md5_lookup = tcp_v4_md5_lookup, |
49a72dfb | 1855 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 YH |
1856 | .md5_add = tcp_v4_md5_add_func, |
1857 | .md5_parse = tcp_v4_parse_md5_keys, | |
cfb6eeb4 | 1858 | }; |
b6332e6c | 1859 | #endif |
cfb6eeb4 | 1860 | |
1da177e4 LT |
1861 | /* NOTE: A lot of things set to zero explicitly by call to |
1862 | * sk_alloc() so need not be done here. | |
1863 | */ | |
1864 | static int tcp_v4_init_sock(struct sock *sk) | |
1865 | { | |
6687e988 | 1866 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
1867 | struct tcp_sock *tp = tcp_sk(sk); |
1868 | ||
1869 | skb_queue_head_init(&tp->out_of_order_queue); | |
1870 | tcp_init_xmit_timers(sk); | |
1871 | tcp_prequeue_init(tp); | |
1872 | ||
6687e988 | 1873 | icsk->icsk_rto = TCP_TIMEOUT_INIT; |
1da177e4 LT |
1874 | tp->mdev = TCP_TIMEOUT_INIT; |
1875 | ||
1876 | /* So many TCP implementations out there (incorrectly) count the | |
1877 | * initial SYN frame in their delayed-ACK and congestion control | |
1878 | * algorithms that we must have the following bandaid to talk | |
1879 | * efficiently to them. -DaveM | |
1880 | */ | |
9ad7c049 | 1881 | tp->snd_cwnd = TCP_INIT_CWND; |
1da177e4 LT |
1882 | |
1883 | /* See draft-stevens-tcpca-spec-01 for discussion of the | |
1884 | * initialization of these values. | |
1885 | */ | |
0b6a05c1 | 1886 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; |
1da177e4 | 1887 | tp->snd_cwnd_clamp = ~0; |
bee7ca9e | 1888 | tp->mss_cache = TCP_MSS_DEFAULT; |
1da177e4 LT |
1889 | |
1890 | tp->reordering = sysctl_tcp_reordering; | |
6687e988 | 1891 | icsk->icsk_ca_ops = &tcp_init_congestion_ops; |
1da177e4 LT |
1892 | |
1893 | sk->sk_state = TCP_CLOSE; | |
1894 | ||
1895 | sk->sk_write_space = sk_stream_write_space; | |
1896 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | |
1897 | ||
8292a17a | 1898 | icsk->icsk_af_ops = &ipv4_specific; |
d83d8461 | 1899 | icsk->icsk_sync_mss = tcp_sync_mss; |
cfb6eeb4 YH |
1900 | #ifdef CONFIG_TCP_MD5SIG |
1901 | tp->af_specific = &tcp_sock_ipv4_specific; | |
1902 | #endif | |
1da177e4 | 1903 | |
435cf559 WAS |
1904 | /* TCP Cookie Transactions */ |
1905 | if (sysctl_tcp_cookie_size > 0) { | |
1906 | /* Default, cookies without s_data_payload. */ | |
1907 | tp->cookie_values = | |
1908 | kzalloc(sizeof(*tp->cookie_values), | |
1909 | sk->sk_allocation); | |
1910 | if (tp->cookie_values != NULL) | |
1911 | kref_init(&tp->cookie_values->kref); | |
1912 | } | |
1913 | /* Presumed zeroed, in order of appearance: | |
1914 | * cookie_in_always, cookie_out_never, | |
1915 | * s_data_constant, s_data_in, s_data_out | |
1916 | */ | |
1da177e4 LT |
1917 | sk->sk_sndbuf = sysctl_tcp_wmem[1]; |
1918 | sk->sk_rcvbuf = sysctl_tcp_rmem[1]; | |
1919 | ||
eb4dea58 | 1920 | local_bh_disable(); |
d1a4c0b3 | 1921 | sock_update_memcg(sk); |
180d8cd9 | 1922 | sk_sockets_allocated_inc(sk); |
eb4dea58 | 1923 | local_bh_enable(); |
1da177e4 LT |
1924 | |
1925 | return 0; | |
1926 | } | |
1927 | ||
7d06b2e0 | 1928 | void tcp_v4_destroy_sock(struct sock *sk) |
1da177e4 LT |
1929 | { |
1930 | struct tcp_sock *tp = tcp_sk(sk); | |
1931 | ||
1932 | tcp_clear_xmit_timers(sk); | |
1933 | ||
6687e988 | 1934 | tcp_cleanup_congestion_control(sk); |
317a76f9 | 1935 | |
1da177e4 | 1936 | /* Cleanup up the write buffer. */ |
fe067e8a | 1937 | tcp_write_queue_purge(sk); |
1da177e4 LT |
1938 | |
1939 | /* Cleans up our, hopefully empty, out_of_order_queue. */ | |
e905a9ed | 1940 | __skb_queue_purge(&tp->out_of_order_queue); |
1da177e4 | 1941 | |
cfb6eeb4 YH |
1942 | #ifdef CONFIG_TCP_MD5SIG |
1943 | /* Clean up the MD5 key list, if any */ | |
1944 | if (tp->md5sig_info) { | |
1945 | tcp_v4_clear_md5_list(sk); | |
1946 | kfree(tp->md5sig_info); | |
1947 | tp->md5sig_info = NULL; | |
1948 | } | |
1949 | #endif | |
1950 | ||
1a2449a8 CL |
1951 | #ifdef CONFIG_NET_DMA |
1952 | /* Cleans up our sk_async_wait_queue */ | |
e905a9ed | 1953 | __skb_queue_purge(&sk->sk_async_wait_queue); |
1a2449a8 CL |
1954 | #endif |
1955 | ||
1da177e4 LT |
1956 | /* Clean prequeue, it must be empty really */ |
1957 | __skb_queue_purge(&tp->ucopy.prequeue); | |
1958 | ||
1959 | /* Clean up a referenced TCP bind bucket. */ | |
463c84b9 | 1960 | if (inet_csk(sk)->icsk_bind_hash) |
ab1e0a13 | 1961 | inet_put_port(sk); |
1da177e4 LT |
1962 | |
1963 | /* | |
1964 | * If sendmsg cached page exists, toss it. | |
1965 | */ | |
1966 | if (sk->sk_sndmsg_page) { | |
1967 | __free_page(sk->sk_sndmsg_page); | |
1968 | sk->sk_sndmsg_page = NULL; | |
1969 | } | |
1970 | ||
435cf559 WAS |
1971 | /* TCP Cookie Transactions */ |
1972 | if (tp->cookie_values != NULL) { | |
1973 | kref_put(&tp->cookie_values->kref, | |
1974 | tcp_cookie_values_release); | |
1975 | tp->cookie_values = NULL; | |
1976 | } | |
1977 | ||
180d8cd9 | 1978 | sk_sockets_allocated_dec(sk); |
d1a4c0b3 | 1979 | sock_release_memcg(sk); |
1da177e4 | 1980 | } |
1da177e4 LT |
1981 | EXPORT_SYMBOL(tcp_v4_destroy_sock); |
1982 | ||
1983 | #ifdef CONFIG_PROC_FS | |
1984 | /* Proc filesystem TCP sock list dumping. */ | |
1985 | ||
3ab5aee7 | 1986 | static inline struct inet_timewait_sock *tw_head(struct hlist_nulls_head *head) |
1da177e4 | 1987 | { |
3ab5aee7 | 1988 | return hlist_nulls_empty(head) ? NULL : |
8feaf0c0 | 1989 | list_entry(head->first, struct inet_timewait_sock, tw_node); |
1da177e4 LT |
1990 | } |
1991 | ||
8feaf0c0 | 1992 | static inline struct inet_timewait_sock *tw_next(struct inet_timewait_sock *tw) |
1da177e4 | 1993 | { |
3ab5aee7 ED |
1994 | return !is_a_nulls(tw->tw_node.next) ? |
1995 | hlist_nulls_entry(tw->tw_node.next, typeof(*tw), tw_node) : NULL; | |
1da177e4 LT |
1996 | } |
1997 | ||
a8b690f9 TH |
1998 | /* |
1999 | * Get next listener socket follow cur. If cur is NULL, get first socket | |
2000 | * starting from bucket given in st->bucket; when st->bucket is zero the | |
2001 | * very first socket in the hash table is returned. | |
2002 | */ | |
1da177e4 LT |
2003 | static void *listening_get_next(struct seq_file *seq, void *cur) |
2004 | { | |
463c84b9 | 2005 | struct inet_connection_sock *icsk; |
c25eb3bf | 2006 | struct hlist_nulls_node *node; |
1da177e4 | 2007 | struct sock *sk = cur; |
5caea4ea | 2008 | struct inet_listen_hashbucket *ilb; |
5799de0b | 2009 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2010 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2011 | |
2012 | if (!sk) { | |
a8b690f9 | 2013 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
5caea4ea | 2014 | spin_lock_bh(&ilb->lock); |
c25eb3bf | 2015 | sk = sk_nulls_head(&ilb->head); |
a8b690f9 | 2016 | st->offset = 0; |
1da177e4 LT |
2017 | goto get_sk; |
2018 | } | |
5caea4ea | 2019 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
1da177e4 | 2020 | ++st->num; |
a8b690f9 | 2021 | ++st->offset; |
1da177e4 LT |
2022 | |
2023 | if (st->state == TCP_SEQ_STATE_OPENREQ) { | |
60236fdd | 2024 | struct request_sock *req = cur; |
1da177e4 | 2025 | |
72a3effa | 2026 | icsk = inet_csk(st->syn_wait_sk); |
1da177e4 LT |
2027 | req = req->dl_next; |
2028 | while (1) { | |
2029 | while (req) { | |
bdccc4ca | 2030 | if (req->rsk_ops->family == st->family) { |
1da177e4 LT |
2031 | cur = req; |
2032 | goto out; | |
2033 | } | |
2034 | req = req->dl_next; | |
2035 | } | |
72a3effa | 2036 | if (++st->sbucket >= icsk->icsk_accept_queue.listen_opt->nr_table_entries) |
1da177e4 LT |
2037 | break; |
2038 | get_req: | |
463c84b9 | 2039 | req = icsk->icsk_accept_queue.listen_opt->syn_table[st->sbucket]; |
1da177e4 | 2040 | } |
1bde5ac4 | 2041 | sk = sk_nulls_next(st->syn_wait_sk); |
1da177e4 | 2042 | st->state = TCP_SEQ_STATE_LISTENING; |
463c84b9 | 2043 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 | 2044 | } else { |
e905a9ed | 2045 | icsk = inet_csk(sk); |
463c84b9 ACM |
2046 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
2047 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) | |
1da177e4 | 2048 | goto start_req; |
463c84b9 | 2049 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1bde5ac4 | 2050 | sk = sk_nulls_next(sk); |
1da177e4 LT |
2051 | } |
2052 | get_sk: | |
c25eb3bf | 2053 | sk_nulls_for_each_from(sk, node) { |
8475ef9f PE |
2054 | if (!net_eq(sock_net(sk), net)) |
2055 | continue; | |
2056 | if (sk->sk_family == st->family) { | |
1da177e4 LT |
2057 | cur = sk; |
2058 | goto out; | |
2059 | } | |
e905a9ed | 2060 | icsk = inet_csk(sk); |
463c84b9 ACM |
2061 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
2062 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) { | |
1da177e4 LT |
2063 | start_req: |
2064 | st->uid = sock_i_uid(sk); | |
2065 | st->syn_wait_sk = sk; | |
2066 | st->state = TCP_SEQ_STATE_OPENREQ; | |
2067 | st->sbucket = 0; | |
2068 | goto get_req; | |
2069 | } | |
463c84b9 | 2070 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 | 2071 | } |
5caea4ea | 2072 | spin_unlock_bh(&ilb->lock); |
a8b690f9 | 2073 | st->offset = 0; |
0f7ff927 | 2074 | if (++st->bucket < INET_LHTABLE_SIZE) { |
5caea4ea ED |
2075 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
2076 | spin_lock_bh(&ilb->lock); | |
c25eb3bf | 2077 | sk = sk_nulls_head(&ilb->head); |
1da177e4 LT |
2078 | goto get_sk; |
2079 | } | |
2080 | cur = NULL; | |
2081 | out: | |
2082 | return cur; | |
2083 | } | |
2084 | ||
2085 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) | |
2086 | { | |
a8b690f9 TH |
2087 | struct tcp_iter_state *st = seq->private; |
2088 | void *rc; | |
2089 | ||
2090 | st->bucket = 0; | |
2091 | st->offset = 0; | |
2092 | rc = listening_get_next(seq, NULL); | |
1da177e4 LT |
2093 | |
2094 | while (rc && *pos) { | |
2095 | rc = listening_get_next(seq, rc); | |
2096 | --*pos; | |
2097 | } | |
2098 | return rc; | |
2099 | } | |
2100 | ||
6eac5604 AK |
2101 | static inline int empty_bucket(struct tcp_iter_state *st) |
2102 | { | |
3ab5aee7 ED |
2103 | return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain) && |
2104 | hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].twchain); | |
6eac5604 AK |
2105 | } |
2106 | ||
a8b690f9 TH |
2107 | /* |
2108 | * Get first established socket starting from bucket given in st->bucket. | |
2109 | * If st->bucket is zero, the very first socket in the hash is returned. | |
2110 | */ | |
1da177e4 LT |
2111 | static void *established_get_first(struct seq_file *seq) |
2112 | { | |
5799de0b | 2113 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2114 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2115 | void *rc = NULL; |
2116 | ||
a8b690f9 TH |
2117 | st->offset = 0; |
2118 | for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { | |
1da177e4 | 2119 | struct sock *sk; |
3ab5aee7 | 2120 | struct hlist_nulls_node *node; |
8feaf0c0 | 2121 | struct inet_timewait_sock *tw; |
9db66bdc | 2122 | spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket); |
1da177e4 | 2123 | |
6eac5604 AK |
2124 | /* Lockless fast path for the common case of empty buckets */ |
2125 | if (empty_bucket(st)) | |
2126 | continue; | |
2127 | ||
9db66bdc | 2128 | spin_lock_bh(lock); |
3ab5aee7 | 2129 | sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { |
f40c8174 | 2130 | if (sk->sk_family != st->family || |
878628fb | 2131 | !net_eq(sock_net(sk), net)) { |
1da177e4 LT |
2132 | continue; |
2133 | } | |
2134 | rc = sk; | |
2135 | goto out; | |
2136 | } | |
2137 | st->state = TCP_SEQ_STATE_TIME_WAIT; | |
8feaf0c0 | 2138 | inet_twsk_for_each(tw, node, |
dbca9b27 | 2139 | &tcp_hashinfo.ehash[st->bucket].twchain) { |
28518fc1 | 2140 | if (tw->tw_family != st->family || |
878628fb | 2141 | !net_eq(twsk_net(tw), net)) { |
1da177e4 LT |
2142 | continue; |
2143 | } | |
2144 | rc = tw; | |
2145 | goto out; | |
2146 | } | |
9db66bdc | 2147 | spin_unlock_bh(lock); |
1da177e4 LT |
2148 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2149 | } | |
2150 | out: | |
2151 | return rc; | |
2152 | } | |
2153 | ||
2154 | static void *established_get_next(struct seq_file *seq, void *cur) | |
2155 | { | |
2156 | struct sock *sk = cur; | |
8feaf0c0 | 2157 | struct inet_timewait_sock *tw; |
3ab5aee7 | 2158 | struct hlist_nulls_node *node; |
5799de0b | 2159 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2160 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2161 | |
2162 | ++st->num; | |
a8b690f9 | 2163 | ++st->offset; |
1da177e4 LT |
2164 | |
2165 | if (st->state == TCP_SEQ_STATE_TIME_WAIT) { | |
2166 | tw = cur; | |
2167 | tw = tw_next(tw); | |
2168 | get_tw: | |
878628fb | 2169 | while (tw && (tw->tw_family != st->family || !net_eq(twsk_net(tw), net))) { |
1da177e4 LT |
2170 | tw = tw_next(tw); |
2171 | } | |
2172 | if (tw) { | |
2173 | cur = tw; | |
2174 | goto out; | |
2175 | } | |
9db66bdc | 2176 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2177 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2178 | ||
6eac5604 | 2179 | /* Look for next non empty bucket */ |
a8b690f9 | 2180 | st->offset = 0; |
f373b53b | 2181 | while (++st->bucket <= tcp_hashinfo.ehash_mask && |
6eac5604 AK |
2182 | empty_bucket(st)) |
2183 | ; | |
f373b53b | 2184 | if (st->bucket > tcp_hashinfo.ehash_mask) |
6eac5604 AK |
2185 | return NULL; |
2186 | ||
9db66bdc | 2187 | spin_lock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
3ab5aee7 | 2188 | sk = sk_nulls_head(&tcp_hashinfo.ehash[st->bucket].chain); |
1da177e4 | 2189 | } else |
3ab5aee7 | 2190 | sk = sk_nulls_next(sk); |
1da177e4 | 2191 | |
3ab5aee7 | 2192 | sk_nulls_for_each_from(sk, node) { |
878628fb | 2193 | if (sk->sk_family == st->family && net_eq(sock_net(sk), net)) |
1da177e4 LT |
2194 | goto found; |
2195 | } | |
2196 | ||
2197 | st->state = TCP_SEQ_STATE_TIME_WAIT; | |
dbca9b27 | 2198 | tw = tw_head(&tcp_hashinfo.ehash[st->bucket].twchain); |
1da177e4 LT |
2199 | goto get_tw; |
2200 | found: | |
2201 | cur = sk; | |
2202 | out: | |
2203 | return cur; | |
2204 | } | |
2205 | ||
2206 | static void *established_get_idx(struct seq_file *seq, loff_t pos) | |
2207 | { | |
a8b690f9 TH |
2208 | struct tcp_iter_state *st = seq->private; |
2209 | void *rc; | |
2210 | ||
2211 | st->bucket = 0; | |
2212 | rc = established_get_first(seq); | |
1da177e4 LT |
2213 | |
2214 | while (rc && pos) { | |
2215 | rc = established_get_next(seq, rc); | |
2216 | --pos; | |
7174259e | 2217 | } |
1da177e4 LT |
2218 | return rc; |
2219 | } | |
2220 | ||
2221 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) | |
2222 | { | |
2223 | void *rc; | |
5799de0b | 2224 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2225 | |
1da177e4 LT |
2226 | st->state = TCP_SEQ_STATE_LISTENING; |
2227 | rc = listening_get_idx(seq, &pos); | |
2228 | ||
2229 | if (!rc) { | |
1da177e4 LT |
2230 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2231 | rc = established_get_idx(seq, pos); | |
2232 | } | |
2233 | ||
2234 | return rc; | |
2235 | } | |
2236 | ||
a8b690f9 TH |
2237 | static void *tcp_seek_last_pos(struct seq_file *seq) |
2238 | { | |
2239 | struct tcp_iter_state *st = seq->private; | |
2240 | int offset = st->offset; | |
2241 | int orig_num = st->num; | |
2242 | void *rc = NULL; | |
2243 | ||
2244 | switch (st->state) { | |
2245 | case TCP_SEQ_STATE_OPENREQ: | |
2246 | case TCP_SEQ_STATE_LISTENING: | |
2247 | if (st->bucket >= INET_LHTABLE_SIZE) | |
2248 | break; | |
2249 | st->state = TCP_SEQ_STATE_LISTENING; | |
2250 | rc = listening_get_next(seq, NULL); | |
2251 | while (offset-- && rc) | |
2252 | rc = listening_get_next(seq, rc); | |
2253 | if (rc) | |
2254 | break; | |
2255 | st->bucket = 0; | |
2256 | /* Fallthrough */ | |
2257 | case TCP_SEQ_STATE_ESTABLISHED: | |
2258 | case TCP_SEQ_STATE_TIME_WAIT: | |
2259 | st->state = TCP_SEQ_STATE_ESTABLISHED; | |
2260 | if (st->bucket > tcp_hashinfo.ehash_mask) | |
2261 | break; | |
2262 | rc = established_get_first(seq); | |
2263 | while (offset-- && rc) | |
2264 | rc = established_get_next(seq, rc); | |
2265 | } | |
2266 | ||
2267 | st->num = orig_num; | |
2268 | ||
2269 | return rc; | |
2270 | } | |
2271 | ||
1da177e4 LT |
2272 | static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) |
2273 | { | |
5799de0b | 2274 | struct tcp_iter_state *st = seq->private; |
a8b690f9 TH |
2275 | void *rc; |
2276 | ||
2277 | if (*pos && *pos == st->last_pos) { | |
2278 | rc = tcp_seek_last_pos(seq); | |
2279 | if (rc) | |
2280 | goto out; | |
2281 | } | |
2282 | ||
1da177e4 LT |
2283 | st->state = TCP_SEQ_STATE_LISTENING; |
2284 | st->num = 0; | |
a8b690f9 TH |
2285 | st->bucket = 0; |
2286 | st->offset = 0; | |
2287 | rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
2288 | ||
2289 | out: | |
2290 | st->last_pos = *pos; | |
2291 | return rc; | |
1da177e4 LT |
2292 | } |
2293 | ||
2294 | static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2295 | { | |
a8b690f9 | 2296 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2297 | void *rc = NULL; |
1da177e4 LT |
2298 | |
2299 | if (v == SEQ_START_TOKEN) { | |
2300 | rc = tcp_get_idx(seq, 0); | |
2301 | goto out; | |
2302 | } | |
1da177e4 LT |
2303 | |
2304 | switch (st->state) { | |
2305 | case TCP_SEQ_STATE_OPENREQ: | |
2306 | case TCP_SEQ_STATE_LISTENING: | |
2307 | rc = listening_get_next(seq, v); | |
2308 | if (!rc) { | |
1da177e4 | 2309 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2310 | st->bucket = 0; |
2311 | st->offset = 0; | |
1da177e4 LT |
2312 | rc = established_get_first(seq); |
2313 | } | |
2314 | break; | |
2315 | case TCP_SEQ_STATE_ESTABLISHED: | |
2316 | case TCP_SEQ_STATE_TIME_WAIT: | |
2317 | rc = established_get_next(seq, v); | |
2318 | break; | |
2319 | } | |
2320 | out: | |
2321 | ++*pos; | |
a8b690f9 | 2322 | st->last_pos = *pos; |
1da177e4 LT |
2323 | return rc; |
2324 | } | |
2325 | ||
2326 | static void tcp_seq_stop(struct seq_file *seq, void *v) | |
2327 | { | |
5799de0b | 2328 | struct tcp_iter_state *st = seq->private; |
1da177e4 LT |
2329 | |
2330 | switch (st->state) { | |
2331 | case TCP_SEQ_STATE_OPENREQ: | |
2332 | if (v) { | |
463c84b9 ACM |
2333 | struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk); |
2334 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); | |
1da177e4 LT |
2335 | } |
2336 | case TCP_SEQ_STATE_LISTENING: | |
2337 | if (v != SEQ_START_TOKEN) | |
5caea4ea | 2338 | spin_unlock_bh(&tcp_hashinfo.listening_hash[st->bucket].lock); |
1da177e4 LT |
2339 | break; |
2340 | case TCP_SEQ_STATE_TIME_WAIT: | |
2341 | case TCP_SEQ_STATE_ESTABLISHED: | |
2342 | if (v) | |
9db66bdc | 2343 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2344 | break; |
2345 | } | |
2346 | } | |
2347 | ||
73cb88ec | 2348 | int tcp_seq_open(struct inode *inode, struct file *file) |
1da177e4 LT |
2349 | { |
2350 | struct tcp_seq_afinfo *afinfo = PDE(inode)->data; | |
1da177e4 | 2351 | struct tcp_iter_state *s; |
52d6f3f1 | 2352 | int err; |
1da177e4 | 2353 | |
52d6f3f1 DL |
2354 | err = seq_open_net(inode, file, &afinfo->seq_ops, |
2355 | sizeof(struct tcp_iter_state)); | |
2356 | if (err < 0) | |
2357 | return err; | |
f40c8174 | 2358 | |
52d6f3f1 | 2359 | s = ((struct seq_file *)file->private_data)->private; |
1da177e4 | 2360 | s->family = afinfo->family; |
a8b690f9 | 2361 | s->last_pos = 0; |
f40c8174 DL |
2362 | return 0; |
2363 | } | |
73cb88ec | 2364 | EXPORT_SYMBOL(tcp_seq_open); |
f40c8174 | 2365 | |
6f8b13bc | 2366 | int tcp_proc_register(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 LT |
2367 | { |
2368 | int rc = 0; | |
2369 | struct proc_dir_entry *p; | |
2370 | ||
9427c4b3 DL |
2371 | afinfo->seq_ops.start = tcp_seq_start; |
2372 | afinfo->seq_ops.next = tcp_seq_next; | |
2373 | afinfo->seq_ops.stop = tcp_seq_stop; | |
2374 | ||
84841c3c | 2375 | p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net, |
73cb88ec | 2376 | afinfo->seq_fops, afinfo); |
84841c3c | 2377 | if (!p) |
1da177e4 LT |
2378 | rc = -ENOMEM; |
2379 | return rc; | |
2380 | } | |
4bc2f18b | 2381 | EXPORT_SYMBOL(tcp_proc_register); |
1da177e4 | 2382 | |
6f8b13bc | 2383 | void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 | 2384 | { |
6f8b13bc | 2385 | proc_net_remove(net, afinfo->name); |
1da177e4 | 2386 | } |
4bc2f18b | 2387 | EXPORT_SYMBOL(tcp_proc_unregister); |
1da177e4 | 2388 | |
cf533ea5 | 2389 | static void get_openreq4(const struct sock *sk, const struct request_sock *req, |
5e659e4c | 2390 | struct seq_file *f, int i, int uid, int *len) |
1da177e4 | 2391 | { |
2e6599cb | 2392 | const struct inet_request_sock *ireq = inet_rsk(req); |
1da177e4 LT |
2393 | int ttd = req->expires - jiffies; |
2394 | ||
5e659e4c | 2395 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
71338aa7 | 2396 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %pK%n", |
1da177e4 | 2397 | i, |
2e6599cb | 2398 | ireq->loc_addr, |
c720c7e8 | 2399 | ntohs(inet_sk(sk)->inet_sport), |
2e6599cb ACM |
2400 | ireq->rmt_addr, |
2401 | ntohs(ireq->rmt_port), | |
1da177e4 LT |
2402 | TCP_SYN_RECV, |
2403 | 0, 0, /* could print option size, but that is af dependent. */ | |
2404 | 1, /* timers active (only the expire timer) */ | |
2405 | jiffies_to_clock_t(ttd), | |
2406 | req->retrans, | |
2407 | uid, | |
2408 | 0, /* non standard timer */ | |
2409 | 0, /* open_requests have no inode */ | |
2410 | atomic_read(&sk->sk_refcnt), | |
5e659e4c PE |
2411 | req, |
2412 | len); | |
1da177e4 LT |
2413 | } |
2414 | ||
5e659e4c | 2415 | static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) |
1da177e4 LT |
2416 | { |
2417 | int timer_active; | |
2418 | unsigned long timer_expires; | |
cf533ea5 | 2419 | const struct tcp_sock *tp = tcp_sk(sk); |
cf4c6bf8 | 2420 | const struct inet_connection_sock *icsk = inet_csk(sk); |
cf533ea5 | 2421 | const struct inet_sock *inet = inet_sk(sk); |
c720c7e8 ED |
2422 | __be32 dest = inet->inet_daddr; |
2423 | __be32 src = inet->inet_rcv_saddr; | |
2424 | __u16 destp = ntohs(inet->inet_dport); | |
2425 | __u16 srcp = ntohs(inet->inet_sport); | |
49d09007 | 2426 | int rx_queue; |
1da177e4 | 2427 | |
463c84b9 | 2428 | if (icsk->icsk_pending == ICSK_TIME_RETRANS) { |
1da177e4 | 2429 | timer_active = 1; |
463c84b9 ACM |
2430 | timer_expires = icsk->icsk_timeout; |
2431 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | |
1da177e4 | 2432 | timer_active = 4; |
463c84b9 | 2433 | timer_expires = icsk->icsk_timeout; |
cf4c6bf8 | 2434 | } else if (timer_pending(&sk->sk_timer)) { |
1da177e4 | 2435 | timer_active = 2; |
cf4c6bf8 | 2436 | timer_expires = sk->sk_timer.expires; |
1da177e4 LT |
2437 | } else { |
2438 | timer_active = 0; | |
2439 | timer_expires = jiffies; | |
2440 | } | |
2441 | ||
49d09007 ED |
2442 | if (sk->sk_state == TCP_LISTEN) |
2443 | rx_queue = sk->sk_ack_backlog; | |
2444 | else | |
2445 | /* | |
2446 | * because we dont lock socket, we might find a transient negative value | |
2447 | */ | |
2448 | rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); | |
2449 | ||
5e659e4c | 2450 | seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " |
71338aa7 | 2451 | "%08X %5d %8d %lu %d %pK %lu %lu %u %u %d%n", |
cf4c6bf8 | 2452 | i, src, srcp, dest, destp, sk->sk_state, |
47da8ee6 | 2453 | tp->write_seq - tp->snd_una, |
49d09007 | 2454 | rx_queue, |
1da177e4 LT |
2455 | timer_active, |
2456 | jiffies_to_clock_t(timer_expires - jiffies), | |
463c84b9 | 2457 | icsk->icsk_retransmits, |
cf4c6bf8 | 2458 | sock_i_uid(sk), |
6687e988 | 2459 | icsk->icsk_probes_out, |
cf4c6bf8 IJ |
2460 | sock_i_ino(sk), |
2461 | atomic_read(&sk->sk_refcnt), sk, | |
7be87351 SH |
2462 | jiffies_to_clock_t(icsk->icsk_rto), |
2463 | jiffies_to_clock_t(icsk->icsk_ack.ato), | |
463c84b9 | 2464 | (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, |
1da177e4 | 2465 | tp->snd_cwnd, |
0b6a05c1 | 2466 | tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh, |
5e659e4c | 2467 | len); |
1da177e4 LT |
2468 | } |
2469 | ||
cf533ea5 | 2470 | static void get_timewait4_sock(const struct inet_timewait_sock *tw, |
5e659e4c | 2471 | struct seq_file *f, int i, int *len) |
1da177e4 | 2472 | { |
23f33c2d | 2473 | __be32 dest, src; |
1da177e4 LT |
2474 | __u16 destp, srcp; |
2475 | int ttd = tw->tw_ttd - jiffies; | |
2476 | ||
2477 | if (ttd < 0) | |
2478 | ttd = 0; | |
2479 | ||
2480 | dest = tw->tw_daddr; | |
2481 | src = tw->tw_rcv_saddr; | |
2482 | destp = ntohs(tw->tw_dport); | |
2483 | srcp = ntohs(tw->tw_sport); | |
2484 | ||
5e659e4c | 2485 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
71338aa7 | 2486 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK%n", |
1da177e4 LT |
2487 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, |
2488 | 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, | |
5e659e4c | 2489 | atomic_read(&tw->tw_refcnt), tw, len); |
1da177e4 LT |
2490 | } |
2491 | ||
2492 | #define TMPSZ 150 | |
2493 | ||
2494 | static int tcp4_seq_show(struct seq_file *seq, void *v) | |
2495 | { | |
5799de0b | 2496 | struct tcp_iter_state *st; |
5e659e4c | 2497 | int len; |
1da177e4 LT |
2498 | |
2499 | if (v == SEQ_START_TOKEN) { | |
2500 | seq_printf(seq, "%-*s\n", TMPSZ - 1, | |
2501 | " sl local_address rem_address st tx_queue " | |
2502 | "rx_queue tr tm->when retrnsmt uid timeout " | |
2503 | "inode"); | |
2504 | goto out; | |
2505 | } | |
2506 | st = seq->private; | |
2507 | ||
2508 | switch (st->state) { | |
2509 | case TCP_SEQ_STATE_LISTENING: | |
2510 | case TCP_SEQ_STATE_ESTABLISHED: | |
5e659e4c | 2511 | get_tcp4_sock(v, seq, st->num, &len); |
1da177e4 LT |
2512 | break; |
2513 | case TCP_SEQ_STATE_OPENREQ: | |
5e659e4c | 2514 | get_openreq4(st->syn_wait_sk, v, seq, st->num, st->uid, &len); |
1da177e4 LT |
2515 | break; |
2516 | case TCP_SEQ_STATE_TIME_WAIT: | |
5e659e4c | 2517 | get_timewait4_sock(v, seq, st->num, &len); |
1da177e4 LT |
2518 | break; |
2519 | } | |
5e659e4c | 2520 | seq_printf(seq, "%*s\n", TMPSZ - 1 - len, ""); |
1da177e4 LT |
2521 | out: |
2522 | return 0; | |
2523 | } | |
2524 | ||
73cb88ec AV |
2525 | static const struct file_operations tcp_afinfo_seq_fops = { |
2526 | .owner = THIS_MODULE, | |
2527 | .open = tcp_seq_open, | |
2528 | .read = seq_read, | |
2529 | .llseek = seq_lseek, | |
2530 | .release = seq_release_net | |
2531 | }; | |
2532 | ||
1da177e4 | 2533 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { |
1da177e4 LT |
2534 | .name = "tcp", |
2535 | .family = AF_INET, | |
73cb88ec | 2536 | .seq_fops = &tcp_afinfo_seq_fops, |
9427c4b3 DL |
2537 | .seq_ops = { |
2538 | .show = tcp4_seq_show, | |
2539 | }, | |
1da177e4 LT |
2540 | }; |
2541 | ||
2c8c1e72 | 2542 | static int __net_init tcp4_proc_init_net(struct net *net) |
757764f6 PE |
2543 | { |
2544 | return tcp_proc_register(net, &tcp4_seq_afinfo); | |
2545 | } | |
2546 | ||
2c8c1e72 | 2547 | static void __net_exit tcp4_proc_exit_net(struct net *net) |
757764f6 PE |
2548 | { |
2549 | tcp_proc_unregister(net, &tcp4_seq_afinfo); | |
2550 | } | |
2551 | ||
2552 | static struct pernet_operations tcp4_net_ops = { | |
2553 | .init = tcp4_proc_init_net, | |
2554 | .exit = tcp4_proc_exit_net, | |
2555 | }; | |
2556 | ||
1da177e4 LT |
2557 | int __init tcp4_proc_init(void) |
2558 | { | |
757764f6 | 2559 | return register_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2560 | } |
2561 | ||
2562 | void tcp4_proc_exit(void) | |
2563 | { | |
757764f6 | 2564 | unregister_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2565 | } |
2566 | #endif /* CONFIG_PROC_FS */ | |
2567 | ||
bf296b12 HX |
2568 | struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb) |
2569 | { | |
b71d1d42 | 2570 | const struct iphdr *iph = skb_gro_network_header(skb); |
bf296b12 HX |
2571 | |
2572 | switch (skb->ip_summed) { | |
2573 | case CHECKSUM_COMPLETE: | |
86911732 | 2574 | if (!tcp_v4_check(skb_gro_len(skb), iph->saddr, iph->daddr, |
bf296b12 HX |
2575 | skb->csum)) { |
2576 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
2577 | break; | |
2578 | } | |
2579 | ||
2580 | /* fall through */ | |
2581 | case CHECKSUM_NONE: | |
2582 | NAPI_GRO_CB(skb)->flush = 1; | |
2583 | return NULL; | |
2584 | } | |
2585 | ||
2586 | return tcp_gro_receive(head, skb); | |
2587 | } | |
bf296b12 HX |
2588 | |
2589 | int tcp4_gro_complete(struct sk_buff *skb) | |
2590 | { | |
b71d1d42 | 2591 | const struct iphdr *iph = ip_hdr(skb); |
bf296b12 HX |
2592 | struct tcphdr *th = tcp_hdr(skb); |
2593 | ||
2594 | th->check = ~tcp_v4_check(skb->len - skb_transport_offset(skb), | |
2595 | iph->saddr, iph->daddr, 0); | |
2596 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; | |
2597 | ||
2598 | return tcp_gro_complete(skb); | |
2599 | } | |
bf296b12 | 2600 | |
1da177e4 LT |
2601 | struct proto tcp_prot = { |
2602 | .name = "TCP", | |
2603 | .owner = THIS_MODULE, | |
2604 | .close = tcp_close, | |
2605 | .connect = tcp_v4_connect, | |
2606 | .disconnect = tcp_disconnect, | |
463c84b9 | 2607 | .accept = inet_csk_accept, |
1da177e4 LT |
2608 | .ioctl = tcp_ioctl, |
2609 | .init = tcp_v4_init_sock, | |
2610 | .destroy = tcp_v4_destroy_sock, | |
2611 | .shutdown = tcp_shutdown, | |
2612 | .setsockopt = tcp_setsockopt, | |
2613 | .getsockopt = tcp_getsockopt, | |
1da177e4 | 2614 | .recvmsg = tcp_recvmsg, |
7ba42910 CG |
2615 | .sendmsg = tcp_sendmsg, |
2616 | .sendpage = tcp_sendpage, | |
1da177e4 | 2617 | .backlog_rcv = tcp_v4_do_rcv, |
ab1e0a13 ACM |
2618 | .hash = inet_hash, |
2619 | .unhash = inet_unhash, | |
2620 | .get_port = inet_csk_get_port, | |
1da177e4 LT |
2621 | .enter_memory_pressure = tcp_enter_memory_pressure, |
2622 | .sockets_allocated = &tcp_sockets_allocated, | |
0a5578cf | 2623 | .orphan_count = &tcp_orphan_count, |
1da177e4 LT |
2624 | .memory_allocated = &tcp_memory_allocated, |
2625 | .memory_pressure = &tcp_memory_pressure, | |
2626 | .sysctl_mem = sysctl_tcp_mem, | |
2627 | .sysctl_wmem = sysctl_tcp_wmem, | |
2628 | .sysctl_rmem = sysctl_tcp_rmem, | |
2629 | .max_header = MAX_TCP_HEADER, | |
2630 | .obj_size = sizeof(struct tcp_sock), | |
3ab5aee7 | 2631 | .slab_flags = SLAB_DESTROY_BY_RCU, |
6d6ee43e | 2632 | .twsk_prot = &tcp_timewait_sock_ops, |
60236fdd | 2633 | .rsk_prot = &tcp_request_sock_ops, |
39d8cda7 | 2634 | .h.hashinfo = &tcp_hashinfo, |
7ba42910 | 2635 | .no_autobind = true, |
543d9cfe ACM |
2636 | #ifdef CONFIG_COMPAT |
2637 | .compat_setsockopt = compat_tcp_setsockopt, | |
2638 | .compat_getsockopt = compat_tcp_getsockopt, | |
2639 | #endif | |
d1a4c0b3 GC |
2640 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM |
2641 | .init_cgroup = tcp_init_cgroup, | |
2642 | .destroy_cgroup = tcp_destroy_cgroup, | |
2643 | .proto_cgroup = tcp_proto_cgroup, | |
2644 | #endif | |
1da177e4 | 2645 | }; |
4bc2f18b | 2646 | EXPORT_SYMBOL(tcp_prot); |
1da177e4 | 2647 | |
046ee902 DL |
2648 | static int __net_init tcp_sk_init(struct net *net) |
2649 | { | |
2650 | return inet_ctl_sock_create(&net->ipv4.tcp_sock, | |
2651 | PF_INET, SOCK_RAW, IPPROTO_TCP, net); | |
2652 | } | |
2653 | ||
2654 | static void __net_exit tcp_sk_exit(struct net *net) | |
2655 | { | |
2656 | inet_ctl_sock_destroy(net->ipv4.tcp_sock); | |
b099ce26 EB |
2657 | } |
2658 | ||
2659 | static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) | |
2660 | { | |
2661 | inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET); | |
046ee902 DL |
2662 | } |
2663 | ||
2664 | static struct pernet_operations __net_initdata tcp_sk_ops = { | |
b099ce26 EB |
2665 | .init = tcp_sk_init, |
2666 | .exit = tcp_sk_exit, | |
2667 | .exit_batch = tcp_sk_exit_batch, | |
046ee902 DL |
2668 | }; |
2669 | ||
9b0f976f | 2670 | void __init tcp_v4_init(void) |
1da177e4 | 2671 | { |
5caea4ea | 2672 | inet_hashinfo_init(&tcp_hashinfo); |
6a1b3054 | 2673 | if (register_pernet_subsys(&tcp_sk_ops)) |
1da177e4 | 2674 | panic("Failed to create the TCP control socket.\n"); |
1da177e4 | 2675 | } |