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1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * Implementation of the Transmission Control Protocol(TCP). | |
7 | * | |
02c30a84 | 8 | * Authors: Ross Biro |
1da177e4 LT |
9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
10 | * Mark Evans, <evansmp@uhura.aston.ac.uk> | |
11 | * Corey Minyard <wf-rch!minyard@relay.EU.net> | |
12 | * Florian La Roche, <flla@stud.uni-sb.de> | |
13 | * Charles Hedrick, <hedrick@klinzhai.rutgers.edu> | |
14 | * Linus Torvalds, <torvalds@cs.helsinki.fi> | |
15 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
16 | * Matthew Dillon, <dillon@apollo.west.oic.com> | |
17 | * Arnt Gulbrandsen, <agulbra@nvg.unit.no> | |
18 | * Jorge Cwik, <jorge@laser.satlink.net> | |
19 | * | |
20 | * Fixes: | |
21 | * Alan Cox : Numerous verify_area() calls | |
22 | * Alan Cox : Set the ACK bit on a reset | |
23 | * Alan Cox : Stopped it crashing if it closed while | |
24 | * sk->inuse=1 and was trying to connect | |
25 | * (tcp_err()). | |
26 | * Alan Cox : All icmp error handling was broken | |
27 | * pointers passed where wrong and the | |
28 | * socket was looked up backwards. Nobody | |
29 | * tested any icmp error code obviously. | |
30 | * Alan Cox : tcp_err() now handled properly. It | |
31 | * wakes people on errors. poll | |
32 | * behaves and the icmp error race | |
33 | * has gone by moving it into sock.c | |
34 | * Alan Cox : tcp_send_reset() fixed to work for | |
35 | * everything not just packets for | |
36 | * unknown sockets. | |
37 | * Alan Cox : tcp option processing. | |
38 | * Alan Cox : Reset tweaked (still not 100%) [Had | |
39 | * syn rule wrong] | |
40 | * Herp Rosmanith : More reset fixes | |
41 | * Alan Cox : No longer acks invalid rst frames. | |
42 | * Acking any kind of RST is right out. | |
43 | * Alan Cox : Sets an ignore me flag on an rst | |
44 | * receive otherwise odd bits of prattle | |
45 | * escape still | |
46 | * Alan Cox : Fixed another acking RST frame bug. | |
47 | * Should stop LAN workplace lockups. | |
48 | * Alan Cox : Some tidyups using the new skb list | |
49 | * facilities | |
50 | * Alan Cox : sk->keepopen now seems to work | |
51 | * Alan Cox : Pulls options out correctly on accepts | |
52 | * Alan Cox : Fixed assorted sk->rqueue->next errors | |
53 | * Alan Cox : PSH doesn't end a TCP read. Switched a | |
54 | * bit to skb ops. | |
55 | * Alan Cox : Tidied tcp_data to avoid a potential | |
56 | * nasty. | |
57 | * Alan Cox : Added some better commenting, as the | |
58 | * tcp is hard to follow | |
59 | * Alan Cox : Removed incorrect check for 20 * psh | |
60 | * Michael O'Reilly : ack < copied bug fix. | |
61 | * Johannes Stille : Misc tcp fixes (not all in yet). | |
62 | * Alan Cox : FIN with no memory -> CRASH | |
63 | * Alan Cox : Added socket option proto entries. | |
64 | * Also added awareness of them to accept. | |
65 | * Alan Cox : Added TCP options (SOL_TCP) | |
66 | * Alan Cox : Switched wakeup calls to callbacks, | |
67 | * so the kernel can layer network | |
68 | * sockets. | |
69 | * Alan Cox : Use ip_tos/ip_ttl settings. | |
70 | * Alan Cox : Handle FIN (more) properly (we hope). | |
71 | * Alan Cox : RST frames sent on unsynchronised | |
72 | * state ack error. | |
73 | * Alan Cox : Put in missing check for SYN bit. | |
74 | * Alan Cox : Added tcp_select_window() aka NET2E | |
75 | * window non shrink trick. | |
76 | * Alan Cox : Added a couple of small NET2E timer | |
77 | * fixes | |
78 | * Charles Hedrick : TCP fixes | |
79 | * Toomas Tamm : TCP window fixes | |
80 | * Alan Cox : Small URG fix to rlogin ^C ack fight | |
81 | * Charles Hedrick : Rewrote most of it to actually work | |
82 | * Linus : Rewrote tcp_read() and URG handling | |
83 | * completely | |
84 | * Gerhard Koerting: Fixed some missing timer handling | |
85 | * Matthew Dillon : Reworked TCP machine states as per RFC | |
86 | * Gerhard Koerting: PC/TCP workarounds | |
87 | * Adam Caldwell : Assorted timer/timing errors | |
88 | * Matthew Dillon : Fixed another RST bug | |
89 | * Alan Cox : Move to kernel side addressing changes. | |
90 | * Alan Cox : Beginning work on TCP fastpathing | |
91 | * (not yet usable) | |
92 | * Arnt Gulbrandsen: Turbocharged tcp_check() routine. | |
93 | * Alan Cox : TCP fast path debugging | |
94 | * Alan Cox : Window clamping | |
95 | * Michael Riepe : Bug in tcp_check() | |
96 | * Matt Dillon : More TCP improvements and RST bug fixes | |
97 | * Matt Dillon : Yet more small nasties remove from the | |
98 | * TCP code (Be very nice to this man if | |
99 | * tcp finally works 100%) 8) | |
100 | * Alan Cox : BSD accept semantics. | |
101 | * Alan Cox : Reset on closedown bug. | |
102 | * Peter De Schrijver : ENOTCONN check missing in tcp_sendto(). | |
103 | * Michael Pall : Handle poll() after URG properly in | |
104 | * all cases. | |
105 | * Michael Pall : Undo the last fix in tcp_read_urg() | |
106 | * (multi URG PUSH broke rlogin). | |
107 | * Michael Pall : Fix the multi URG PUSH problem in | |
108 | * tcp_readable(), poll() after URG | |
109 | * works now. | |
110 | * Michael Pall : recv(...,MSG_OOB) never blocks in the | |
111 | * BSD api. | |
112 | * Alan Cox : Changed the semantics of sk->socket to | |
113 | * fix a race and a signal problem with | |
114 | * accept() and async I/O. | |
115 | * Alan Cox : Relaxed the rules on tcp_sendto(). | |
116 | * Yury Shevchuk : Really fixed accept() blocking problem. | |
117 | * Craig I. Hagan : Allow for BSD compatible TIME_WAIT for | |
118 | * clients/servers which listen in on | |
119 | * fixed ports. | |
120 | * Alan Cox : Cleaned the above up and shrank it to | |
121 | * a sensible code size. | |
122 | * Alan Cox : Self connect lockup fix. | |
123 | * Alan Cox : No connect to multicast. | |
124 | * Ross Biro : Close unaccepted children on master | |
125 | * socket close. | |
126 | * Alan Cox : Reset tracing code. | |
127 | * Alan Cox : Spurious resets on shutdown. | |
128 | * Alan Cox : Giant 15 minute/60 second timer error | |
129 | * Alan Cox : Small whoops in polling before an | |
130 | * accept. | |
131 | * Alan Cox : Kept the state trace facility since | |
132 | * it's handy for debugging. | |
133 | * Alan Cox : More reset handler fixes. | |
134 | * Alan Cox : Started rewriting the code based on | |
135 | * the RFC's for other useful protocol | |
136 | * references see: Comer, KA9Q NOS, and | |
137 | * for a reference on the difference | |
138 | * between specifications and how BSD | |
139 | * works see the 4.4lite source. | |
140 | * A.N.Kuznetsov : Don't time wait on completion of tidy | |
141 | * close. | |
142 | * Linus Torvalds : Fin/Shutdown & copied_seq changes. | |
143 | * Linus Torvalds : Fixed BSD port reuse to work first syn | |
144 | * Alan Cox : Reimplemented timers as per the RFC | |
145 | * and using multiple timers for sanity. | |
146 | * Alan Cox : Small bug fixes, and a lot of new | |
147 | * comments. | |
148 | * Alan Cox : Fixed dual reader crash by locking | |
149 | * the buffers (much like datagram.c) | |
150 | * Alan Cox : Fixed stuck sockets in probe. A probe | |
151 | * now gets fed up of retrying without | |
152 | * (even a no space) answer. | |
153 | * Alan Cox : Extracted closing code better | |
154 | * Alan Cox : Fixed the closing state machine to | |
155 | * resemble the RFC. | |
156 | * Alan Cox : More 'per spec' fixes. | |
157 | * Jorge Cwik : Even faster checksumming. | |
158 | * Alan Cox : tcp_data() doesn't ack illegal PSH | |
159 | * only frames. At least one pc tcp stack | |
160 | * generates them. | |
161 | * Alan Cox : Cache last socket. | |
162 | * Alan Cox : Per route irtt. | |
163 | * Matt Day : poll()->select() match BSD precisely on error | |
164 | * Alan Cox : New buffers | |
165 | * Marc Tamsky : Various sk->prot->retransmits and | |
166 | * sk->retransmits misupdating fixed. | |
167 | * Fixed tcp_write_timeout: stuck close, | |
168 | * and TCP syn retries gets used now. | |
169 | * Mark Yarvis : In tcp_read_wakeup(), don't send an | |
170 | * ack if state is TCP_CLOSED. | |
171 | * Alan Cox : Look up device on a retransmit - routes may | |
172 | * change. Doesn't yet cope with MSS shrink right | |
173 | * but it's a start! | |
174 | * Marc Tamsky : Closing in closing fixes. | |
175 | * Mike Shaver : RFC1122 verifications. | |
176 | * Alan Cox : rcv_saddr errors. | |
177 | * Alan Cox : Block double connect(). | |
178 | * Alan Cox : Small hooks for enSKIP. | |
179 | * Alexey Kuznetsov: Path MTU discovery. | |
180 | * Alan Cox : Support soft errors. | |
181 | * Alan Cox : Fix MTU discovery pathological case | |
182 | * when the remote claims no mtu! | |
183 | * Marc Tamsky : TCP_CLOSE fix. | |
184 | * Colin (G3TNE) : Send a reset on syn ack replies in | |
185 | * window but wrong (fixes NT lpd problems) | |
186 | * Pedro Roque : Better TCP window handling, delayed ack. | |
187 | * Joerg Reuter : No modification of locked buffers in | |
188 | * tcp_do_retransmit() | |
189 | * Eric Schenk : Changed receiver side silly window | |
190 | * avoidance algorithm to BSD style | |
191 | * algorithm. This doubles throughput | |
192 | * against machines running Solaris, | |
193 | * and seems to result in general | |
194 | * improvement. | |
195 | * Stefan Magdalinski : adjusted tcp_readable() to fix FIONREAD | |
196 | * Willy Konynenberg : Transparent proxying support. | |
197 | * Mike McLagan : Routing by source | |
198 | * Keith Owens : Do proper merging with partial SKB's in | |
199 | * tcp_do_sendmsg to avoid burstiness. | |
200 | * Eric Schenk : Fix fast close down bug with | |
201 | * shutdown() followed by close(). | |
202 | * Andi Kleen : Make poll agree with SIGIO | |
203 | * Salvatore Sanfilippo : Support SO_LINGER with linger == 1 and | |
204 | * lingertime == 0 (RFC 793 ABORT Call) | |
205 | * Hirokazu Takahashi : Use copy_from_user() instead of | |
206 | * csum_and_copy_from_user() if possible. | |
207 | * | |
208 | * This program is free software; you can redistribute it and/or | |
209 | * modify it under the terms of the GNU General Public License | |
210 | * as published by the Free Software Foundation; either version | |
211 | * 2 of the License, or(at your option) any later version. | |
212 | * | |
213 | * Description of States: | |
214 | * | |
215 | * TCP_SYN_SENT sent a connection request, waiting for ack | |
216 | * | |
217 | * TCP_SYN_RECV received a connection request, sent ack, | |
218 | * waiting for final ack in three-way handshake. | |
219 | * | |
220 | * TCP_ESTABLISHED connection established | |
221 | * | |
222 | * TCP_FIN_WAIT1 our side has shutdown, waiting to complete | |
223 | * transmission of remaining buffered data | |
224 | * | |
225 | * TCP_FIN_WAIT2 all buffered data sent, waiting for remote | |
226 | * to shutdown | |
227 | * | |
228 | * TCP_CLOSING both sides have shutdown but we still have | |
229 | * data we have to finish sending | |
230 | * | |
231 | * TCP_TIME_WAIT timeout to catch resent junk before entering | |
232 | * closed, can only be entered from FIN_WAIT2 | |
233 | * or CLOSING. Required because the other end | |
234 | * may not have gotten our last ACK causing it | |
235 | * to retransmit the data packet (which we ignore) | |
236 | * | |
237 | * TCP_CLOSE_WAIT remote side has shutdown and is waiting for | |
238 | * us to finish writing our data and to shutdown | |
239 | * (we have to close() to move on to LAST_ACK) | |
240 | * | |
241 | * TCP_LAST_ACK out side has shutdown after remote has | |
242 | * shutdown. There may still be data in our | |
243 | * buffer that we have to finish sending | |
244 | * | |
245 | * TCP_CLOSE socket is finished | |
246 | */ | |
247 | ||
172589cc | 248 | #include <linux/kernel.h> |
1da177e4 LT |
249 | #include <linux/module.h> |
250 | #include <linux/types.h> | |
251 | #include <linux/fcntl.h> | |
252 | #include <linux/poll.h> | |
253 | #include <linux/init.h> | |
1da177e4 | 254 | #include <linux/fs.h> |
9c55e01c | 255 | #include <linux/skbuff.h> |
81b23b4a | 256 | #include <linux/scatterlist.h> |
9c55e01c JA |
257 | #include <linux/splice.h> |
258 | #include <linux/net.h> | |
259 | #include <linux/socket.h> | |
1da177e4 LT |
260 | #include <linux/random.h> |
261 | #include <linux/bootmem.h> | |
57413ebc MS |
262 | #include <linux/highmem.h> |
263 | #include <linux/swap.h> | |
b8059ead | 264 | #include <linux/cache.h> |
f4c50d99 | 265 | #include <linux/err.h> |
cfb6eeb4 | 266 | #include <linux/crypto.h> |
1da177e4 LT |
267 | |
268 | #include <net/icmp.h> | |
269 | #include <net/tcp.h> | |
270 | #include <net/xfrm.h> | |
271 | #include <net/ip.h> | |
1a2449a8 | 272 | #include <net/netdma.h> |
9c55e01c | 273 | #include <net/sock.h> |
1da177e4 LT |
274 | |
275 | #include <asm/uaccess.h> | |
276 | #include <asm/ioctls.h> | |
277 | ||
ab32ea5d | 278 | int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT; |
1da177e4 | 279 | |
dd24c001 | 280 | struct percpu_counter tcp_orphan_count; |
0a5578cf ACM |
281 | EXPORT_SYMBOL_GPL(tcp_orphan_count); |
282 | ||
b8059ead DM |
283 | int sysctl_tcp_mem[3] __read_mostly; |
284 | int sysctl_tcp_wmem[3] __read_mostly; | |
285 | int sysctl_tcp_rmem[3] __read_mostly; | |
1da177e4 LT |
286 | |
287 | EXPORT_SYMBOL(sysctl_tcp_mem); | |
288 | EXPORT_SYMBOL(sysctl_tcp_rmem); | |
289 | EXPORT_SYMBOL(sysctl_tcp_wmem); | |
290 | ||
291 | atomic_t tcp_memory_allocated; /* Current allocated memory. */ | |
1da177e4 | 292 | EXPORT_SYMBOL(tcp_memory_allocated); |
1748376b ED |
293 | |
294 | /* | |
295 | * Current number of TCP sockets. | |
296 | */ | |
297 | struct percpu_counter tcp_sockets_allocated; | |
1da177e4 LT |
298 | EXPORT_SYMBOL(tcp_sockets_allocated); |
299 | ||
9c55e01c JA |
300 | /* |
301 | * TCP splice context | |
302 | */ | |
303 | struct tcp_splice_state { | |
304 | struct pipe_inode_info *pipe; | |
305 | size_t len; | |
306 | unsigned int flags; | |
307 | }; | |
308 | ||
1da177e4 LT |
309 | /* |
310 | * Pressure flag: try to collapse. | |
311 | * Technical note: it is used by multiple contexts non atomically. | |
3ab224be | 312 | * All the __sk_mem_schedule() is of this nature: accounting |
1da177e4 LT |
313 | * is strict, actions are advisory and have some latency. |
314 | */ | |
4103f8cd | 315 | int tcp_memory_pressure __read_mostly; |
1da177e4 LT |
316 | |
317 | EXPORT_SYMBOL(tcp_memory_pressure); | |
318 | ||
5c52ba17 | 319 | void tcp_enter_memory_pressure(struct sock *sk) |
1da177e4 LT |
320 | { |
321 | if (!tcp_memory_pressure) { | |
4e673444 | 322 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURES); |
1da177e4 LT |
323 | tcp_memory_pressure = 1; |
324 | } | |
325 | } | |
326 | ||
327 | EXPORT_SYMBOL(tcp_enter_memory_pressure); | |
328 | ||
1da177e4 LT |
329 | /* |
330 | * Wait for a TCP event. | |
331 | * | |
332 | * Note that we don't need to lock the socket, as the upper poll layers | |
333 | * take care of normal races (between the test and the event) and we don't | |
334 | * go look at any of the socket buffers directly. | |
335 | */ | |
336 | unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait) | |
337 | { | |
338 | unsigned int mask; | |
339 | struct sock *sk = sock->sk; | |
340 | struct tcp_sock *tp = tcp_sk(sk); | |
341 | ||
342 | poll_wait(file, sk->sk_sleep, wait); | |
343 | if (sk->sk_state == TCP_LISTEN) | |
dc40c7bc | 344 | return inet_csk_listen_poll(sk); |
1da177e4 LT |
345 | |
346 | /* Socket is not locked. We are protected from async events | |
70efce27 WN |
347 | * by poll logic and correct handling of state changes |
348 | * made by other threads is impossible in any case. | |
1da177e4 LT |
349 | */ |
350 | ||
351 | mask = 0; | |
352 | if (sk->sk_err) | |
353 | mask = POLLERR; | |
354 | ||
355 | /* | |
356 | * POLLHUP is certainly not done right. But poll() doesn't | |
357 | * have a notion of HUP in just one direction, and for a | |
358 | * socket the read side is more interesting. | |
359 | * | |
360 | * Some poll() documentation says that POLLHUP is incompatible | |
361 | * with the POLLOUT/POLLWR flags, so somebody should check this | |
362 | * all. But careful, it tends to be safer to return too many | |
363 | * bits than too few, and you can easily break real applications | |
364 | * if you don't tell them that something has hung up! | |
365 | * | |
366 | * Check-me. | |
367 | * | |
368 | * Check number 1. POLLHUP is _UNMASKABLE_ event (see UNIX98 and | |
369 | * our fs/select.c). It means that after we received EOF, | |
370 | * poll always returns immediately, making impossible poll() on write() | |
371 | * in state CLOSE_WAIT. One solution is evident --- to set POLLHUP | |
372 | * if and only if shutdown has been made in both directions. | |
373 | * Actually, it is interesting to look how Solaris and DUX | |
70efce27 | 374 | * solve this dilemma. I would prefer, if POLLHUP were maskable, |
1da177e4 LT |
375 | * then we could set it on SND_SHUTDOWN. BTW examples given |
376 | * in Stevens' books assume exactly this behaviour, it explains | |
70efce27 | 377 | * why POLLHUP is incompatible with POLLOUT. --ANK |
1da177e4 LT |
378 | * |
379 | * NOTE. Check for TCP_CLOSE is added. The goal is to prevent | |
380 | * blocking on fresh not-connected or disconnected socket. --ANK | |
381 | */ | |
382 | if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == TCP_CLOSE) | |
383 | mask |= POLLHUP; | |
384 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
f348d70a | 385 | mask |= POLLIN | POLLRDNORM | POLLRDHUP; |
1da177e4 LT |
386 | |
387 | /* Connected? */ | |
388 | if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV)) { | |
c7004482 DM |
389 | int target = sock_rcvlowat(sk, 0, INT_MAX); |
390 | ||
391 | if (tp->urg_seq == tp->copied_seq && | |
392 | !sock_flag(sk, SOCK_URGINLINE) && | |
393 | tp->urg_data) | |
394 | target--; | |
395 | ||
1da177e4 LT |
396 | /* Potential race condition. If read of tp below will |
397 | * escape above sk->sk_state, we can be illegally awaken | |
398 | * in SYN_* states. */ | |
c7004482 | 399 | if (tp->rcv_nxt - tp->copied_seq >= target) |
1da177e4 LT |
400 | mask |= POLLIN | POLLRDNORM; |
401 | ||
402 | if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { | |
403 | if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) { | |
404 | mask |= POLLOUT | POLLWRNORM; | |
405 | } else { /* send SIGIO later */ | |
406 | set_bit(SOCK_ASYNC_NOSPACE, | |
407 | &sk->sk_socket->flags); | |
408 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
409 | ||
410 | /* Race breaker. If space is freed after | |
411 | * wspace test but before the flags are set, | |
412 | * IO signal will be lost. | |
413 | */ | |
414 | if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) | |
415 | mask |= POLLOUT | POLLWRNORM; | |
416 | } | |
417 | } | |
418 | ||
419 | if (tp->urg_data & TCP_URG_VALID) | |
420 | mask |= POLLPRI; | |
421 | } | |
422 | return mask; | |
423 | } | |
424 | ||
425 | int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg) | |
426 | { | |
427 | struct tcp_sock *tp = tcp_sk(sk); | |
428 | int answ; | |
429 | ||
430 | switch (cmd) { | |
431 | case SIOCINQ: | |
432 | if (sk->sk_state == TCP_LISTEN) | |
433 | return -EINVAL; | |
434 | ||
435 | lock_sock(sk); | |
436 | if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) | |
437 | answ = 0; | |
438 | else if (sock_flag(sk, SOCK_URGINLINE) || | |
439 | !tp->urg_data || | |
440 | before(tp->urg_seq, tp->copied_seq) || | |
441 | !before(tp->urg_seq, tp->rcv_nxt)) { | |
442 | answ = tp->rcv_nxt - tp->copied_seq; | |
443 | ||
444 | /* Subtract 1, if FIN is in queue. */ | |
445 | if (answ && !skb_queue_empty(&sk->sk_receive_queue)) | |
446 | answ -= | |
aa8223c7 | 447 | tcp_hdr((struct sk_buff *)sk->sk_receive_queue.prev)->fin; |
1da177e4 LT |
448 | } else |
449 | answ = tp->urg_seq - tp->copied_seq; | |
450 | release_sock(sk); | |
451 | break; | |
452 | case SIOCATMARK: | |
453 | answ = tp->urg_data && tp->urg_seq == tp->copied_seq; | |
454 | break; | |
455 | case SIOCOUTQ: | |
456 | if (sk->sk_state == TCP_LISTEN) | |
457 | return -EINVAL; | |
458 | ||
459 | if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) | |
460 | answ = 0; | |
461 | else | |
462 | answ = tp->write_seq - tp->snd_una; | |
463 | break; | |
464 | default: | |
465 | return -ENOIOCTLCMD; | |
3ff50b79 | 466 | } |
1da177e4 LT |
467 | |
468 | return put_user(answ, (int __user *)arg); | |
469 | } | |
470 | ||
1da177e4 LT |
471 | static inline void tcp_mark_push(struct tcp_sock *tp, struct sk_buff *skb) |
472 | { | |
473 | TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH; | |
474 | tp->pushed_seq = tp->write_seq; | |
475 | } | |
476 | ||
477 | static inline int forced_push(struct tcp_sock *tp) | |
478 | { | |
479 | return after(tp->write_seq, tp->pushed_seq + (tp->max_window >> 1)); | |
480 | } | |
481 | ||
9e412ba7 | 482 | static inline void skb_entail(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 483 | { |
9e412ba7 | 484 | struct tcp_sock *tp = tcp_sk(sk); |
352d4800 ACM |
485 | struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); |
486 | ||
487 | skb->csum = 0; | |
488 | tcb->seq = tcb->end_seq = tp->write_seq; | |
489 | tcb->flags = TCPCB_FLAG_ACK; | |
490 | tcb->sacked = 0; | |
1da177e4 | 491 | skb_header_release(skb); |
fe067e8a | 492 | tcp_add_write_queue_tail(sk, skb); |
3ab224be HA |
493 | sk->sk_wmem_queued += skb->truesize; |
494 | sk_mem_charge(sk, skb->truesize); | |
89ebd197 | 495 | if (tp->nonagle & TCP_NAGLE_PUSH) |
e905a9ed | 496 | tp->nonagle &= ~TCP_NAGLE_PUSH; |
1da177e4 LT |
497 | } |
498 | ||
499 | static inline void tcp_mark_urg(struct tcp_sock *tp, int flags, | |
500 | struct sk_buff *skb) | |
501 | { | |
33f5f57e | 502 | if (flags & MSG_OOB) |
1da177e4 | 503 | tp->snd_up = tp->write_seq; |
1da177e4 LT |
504 | } |
505 | ||
9e412ba7 IJ |
506 | static inline void tcp_push(struct sock *sk, int flags, int mss_now, |
507 | int nonagle) | |
1da177e4 | 508 | { |
9e412ba7 IJ |
509 | struct tcp_sock *tp = tcp_sk(sk); |
510 | ||
fe067e8a DM |
511 | if (tcp_send_head(sk)) { |
512 | struct sk_buff *skb = tcp_write_queue_tail(sk); | |
1da177e4 LT |
513 | if (!(flags & MSG_MORE) || forced_push(tp)) |
514 | tcp_mark_push(tp, skb); | |
515 | tcp_mark_urg(tp, flags, skb); | |
9e412ba7 | 516 | __tcp_push_pending_frames(sk, mss_now, |
1da177e4 LT |
517 | (flags & MSG_MORE) ? TCP_NAGLE_CORK : nonagle); |
518 | } | |
519 | } | |
520 | ||
6ff7751d AB |
521 | static int tcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, |
522 | unsigned int offset, size_t len) | |
9c55e01c JA |
523 | { |
524 | struct tcp_splice_state *tss = rd_desc->arg.data; | |
525 | ||
526 | return skb_splice_bits(skb, offset, tss->pipe, tss->len, tss->flags); | |
527 | } | |
528 | ||
529 | static int __tcp_splice_read(struct sock *sk, struct tcp_splice_state *tss) | |
530 | { | |
531 | /* Store TCP splice context information in read_descriptor_t. */ | |
532 | read_descriptor_t rd_desc = { | |
533 | .arg.data = tss, | |
534 | }; | |
535 | ||
536 | return tcp_read_sock(sk, &rd_desc, tcp_splice_data_recv); | |
537 | } | |
538 | ||
539 | /** | |
540 | * tcp_splice_read - splice data from TCP socket to a pipe | |
541 | * @sock: socket to splice from | |
542 | * @ppos: position (not valid) | |
543 | * @pipe: pipe to splice to | |
544 | * @len: number of bytes to splice | |
545 | * @flags: splice modifier flags | |
546 | * | |
547 | * Description: | |
548 | * Will read pages from given socket and fill them into a pipe. | |
549 | * | |
550 | **/ | |
551 | ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos, | |
552 | struct pipe_inode_info *pipe, size_t len, | |
553 | unsigned int flags) | |
554 | { | |
555 | struct sock *sk = sock->sk; | |
556 | struct tcp_splice_state tss = { | |
557 | .pipe = pipe, | |
558 | .len = len, | |
559 | .flags = flags, | |
560 | }; | |
561 | long timeo; | |
562 | ssize_t spliced; | |
563 | int ret; | |
564 | ||
565 | /* | |
566 | * We can't seek on a socket input | |
567 | */ | |
568 | if (unlikely(*ppos)) | |
569 | return -ESPIPE; | |
570 | ||
571 | ret = spliced = 0; | |
572 | ||
573 | lock_sock(sk); | |
574 | ||
575 | timeo = sock_rcvtimeo(sk, flags & SPLICE_F_NONBLOCK); | |
576 | while (tss.len) { | |
577 | ret = __tcp_splice_read(sk, &tss); | |
578 | if (ret < 0) | |
579 | break; | |
580 | else if (!ret) { | |
581 | if (spliced) | |
582 | break; | |
583 | if (flags & SPLICE_F_NONBLOCK) { | |
584 | ret = -EAGAIN; | |
585 | break; | |
586 | } | |
587 | if (sock_flag(sk, SOCK_DONE)) | |
588 | break; | |
589 | if (sk->sk_err) { | |
590 | ret = sock_error(sk); | |
591 | break; | |
592 | } | |
593 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
594 | break; | |
595 | if (sk->sk_state == TCP_CLOSE) { | |
596 | /* | |
597 | * This occurs when user tries to read | |
598 | * from never connected socket. | |
599 | */ | |
600 | if (!sock_flag(sk, SOCK_DONE)) | |
601 | ret = -ENOTCONN; | |
602 | break; | |
603 | } | |
604 | if (!timeo) { | |
605 | ret = -EAGAIN; | |
606 | break; | |
607 | } | |
608 | sk_wait_data(sk, &timeo); | |
609 | if (signal_pending(current)) { | |
610 | ret = sock_intr_errno(timeo); | |
611 | break; | |
612 | } | |
613 | continue; | |
614 | } | |
615 | tss.len -= ret; | |
616 | spliced += ret; | |
617 | ||
618 | release_sock(sk); | |
619 | lock_sock(sk); | |
620 | ||
621 | if (sk->sk_err || sk->sk_state == TCP_CLOSE || | |
622 | (sk->sk_shutdown & RCV_SHUTDOWN) || !timeo || | |
623 | signal_pending(current)) | |
624 | break; | |
625 | } | |
626 | ||
627 | release_sock(sk); | |
628 | ||
629 | if (spliced) | |
630 | return spliced; | |
631 | ||
632 | return ret; | |
633 | } | |
634 | ||
df97c708 | 635 | struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp) |
f561d0f2 PE |
636 | { |
637 | struct sk_buff *skb; | |
638 | ||
639 | /* The TCP header must be at least 32-bit aligned. */ | |
640 | size = ALIGN(size, 4); | |
641 | ||
642 | skb = alloc_skb_fclone(size + sk->sk_prot->max_header, gfp); | |
643 | if (skb) { | |
3ab224be | 644 | if (sk_wmem_schedule(sk, skb->truesize)) { |
f561d0f2 PE |
645 | /* |
646 | * Make sure that we have exactly size bytes | |
647 | * available to the caller, no more, no less. | |
648 | */ | |
649 | skb_reserve(skb, skb_tailroom(skb) - size); | |
650 | return skb; | |
651 | } | |
652 | __kfree_skb(skb); | |
653 | } else { | |
5c52ba17 | 654 | sk->sk_prot->enter_memory_pressure(sk); |
f561d0f2 PE |
655 | sk_stream_moderate_sndbuf(sk); |
656 | } | |
657 | return NULL; | |
658 | } | |
659 | ||
1da177e4 LT |
660 | static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffset, |
661 | size_t psize, int flags) | |
662 | { | |
663 | struct tcp_sock *tp = tcp_sk(sk); | |
c1b4a7e6 | 664 | int mss_now, size_goal; |
1da177e4 LT |
665 | int err; |
666 | ssize_t copied; | |
667 | long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); | |
668 | ||
669 | /* Wait for a connection to finish. */ | |
670 | if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) | |
671 | if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) | |
672 | goto out_err; | |
673 | ||
674 | clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
675 | ||
676 | mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); | |
c1b4a7e6 | 677 | size_goal = tp->xmit_size_goal; |
1da177e4 LT |
678 | copied = 0; |
679 | ||
680 | err = -EPIPE; | |
681 | if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) | |
682 | goto do_error; | |
683 | ||
684 | while (psize > 0) { | |
fe067e8a | 685 | struct sk_buff *skb = tcp_write_queue_tail(sk); |
1da177e4 LT |
686 | struct page *page = pages[poffset / PAGE_SIZE]; |
687 | int copy, i, can_coalesce; | |
688 | int offset = poffset % PAGE_SIZE; | |
689 | int size = min_t(size_t, psize, PAGE_SIZE - offset); | |
690 | ||
fe067e8a | 691 | if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0) { |
1da177e4 LT |
692 | new_segment: |
693 | if (!sk_stream_memory_free(sk)) | |
694 | goto wait_for_sndbuf; | |
695 | ||
df97c708 | 696 | skb = sk_stream_alloc_skb(sk, 0, sk->sk_allocation); |
1da177e4 LT |
697 | if (!skb) |
698 | goto wait_for_memory; | |
699 | ||
9e412ba7 | 700 | skb_entail(sk, skb); |
c1b4a7e6 | 701 | copy = size_goal; |
1da177e4 LT |
702 | } |
703 | ||
704 | if (copy > size) | |
705 | copy = size; | |
706 | ||
707 | i = skb_shinfo(skb)->nr_frags; | |
708 | can_coalesce = skb_can_coalesce(skb, i, page, offset); | |
709 | if (!can_coalesce && i >= MAX_SKB_FRAGS) { | |
710 | tcp_mark_push(tp, skb); | |
711 | goto new_segment; | |
712 | } | |
3ab224be | 713 | if (!sk_wmem_schedule(sk, copy)) |
1da177e4 | 714 | goto wait_for_memory; |
e905a9ed | 715 | |
1da177e4 LT |
716 | if (can_coalesce) { |
717 | skb_shinfo(skb)->frags[i - 1].size += copy; | |
718 | } else { | |
719 | get_page(page); | |
720 | skb_fill_page_desc(skb, i, page, offset, copy); | |
721 | } | |
722 | ||
723 | skb->len += copy; | |
724 | skb->data_len += copy; | |
725 | skb->truesize += copy; | |
726 | sk->sk_wmem_queued += copy; | |
3ab224be | 727 | sk_mem_charge(sk, copy); |
84fa7933 | 728 | skb->ip_summed = CHECKSUM_PARTIAL; |
1da177e4 LT |
729 | tp->write_seq += copy; |
730 | TCP_SKB_CB(skb)->end_seq += copy; | |
7967168c | 731 | skb_shinfo(skb)->gso_segs = 0; |
1da177e4 LT |
732 | |
733 | if (!copied) | |
734 | TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_PSH; | |
735 | ||
736 | copied += copy; | |
737 | poffset += copy; | |
738 | if (!(psize -= copy)) | |
739 | goto out; | |
740 | ||
69d15067 | 741 | if (skb->len < size_goal || (flags & MSG_OOB)) |
1da177e4 LT |
742 | continue; |
743 | ||
744 | if (forced_push(tp)) { | |
745 | tcp_mark_push(tp, skb); | |
9e412ba7 | 746 | __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH); |
fe067e8a | 747 | } else if (skb == tcp_send_head(sk)) |
1da177e4 LT |
748 | tcp_push_one(sk, mss_now); |
749 | continue; | |
750 | ||
751 | wait_for_sndbuf: | |
752 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
753 | wait_for_memory: | |
754 | if (copied) | |
9e412ba7 | 755 | tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH); |
1da177e4 LT |
756 | |
757 | if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) | |
758 | goto do_error; | |
759 | ||
760 | mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); | |
c1b4a7e6 | 761 | size_goal = tp->xmit_size_goal; |
1da177e4 LT |
762 | } |
763 | ||
764 | out: | |
765 | if (copied) | |
9e412ba7 | 766 | tcp_push(sk, flags, mss_now, tp->nonagle); |
1da177e4 LT |
767 | return copied; |
768 | ||
769 | do_error: | |
770 | if (copied) | |
771 | goto out; | |
772 | out_err: | |
773 | return sk_stream_error(sk, flags, err); | |
774 | } | |
775 | ||
776 | ssize_t tcp_sendpage(struct socket *sock, struct page *page, int offset, | |
777 | size_t size, int flags) | |
778 | { | |
779 | ssize_t res; | |
780 | struct sock *sk = sock->sk; | |
781 | ||
1da177e4 | 782 | if (!(sk->sk_route_caps & NETIF_F_SG) || |
8648b305 | 783 | !(sk->sk_route_caps & NETIF_F_ALL_CSUM)) |
1da177e4 LT |
784 | return sock_no_sendpage(sock, page, offset, size, flags); |
785 | ||
1da177e4 LT |
786 | lock_sock(sk); |
787 | TCP_CHECK_TIMER(sk); | |
788 | res = do_tcp_sendpages(sk, &page, offset, size, flags); | |
789 | TCP_CHECK_TIMER(sk); | |
790 | release_sock(sk); | |
791 | return res; | |
792 | } | |
793 | ||
794 | #define TCP_PAGE(sk) (sk->sk_sndmsg_page) | |
795 | #define TCP_OFF(sk) (sk->sk_sndmsg_off) | |
796 | ||
9e412ba7 | 797 | static inline int select_size(struct sock *sk) |
1da177e4 | 798 | { |
9e412ba7 | 799 | struct tcp_sock *tp = tcp_sk(sk); |
c1b4a7e6 | 800 | int tmp = tp->mss_cache; |
1da177e4 | 801 | |
b4e26f5e | 802 | if (sk->sk_route_caps & NETIF_F_SG) { |
bcd76111 | 803 | if (sk_can_gso(sk)) |
b4e26f5e DM |
804 | tmp = 0; |
805 | else { | |
806 | int pgbreak = SKB_MAX_HEAD(MAX_TCP_HEADER); | |
807 | ||
808 | if (tmp >= pgbreak && | |
809 | tmp <= pgbreak + (MAX_SKB_FRAGS - 1) * PAGE_SIZE) | |
810 | tmp = pgbreak; | |
811 | } | |
812 | } | |
1da177e4 | 813 | |
1da177e4 LT |
814 | return tmp; |
815 | } | |
816 | ||
3516ffb0 | 817 | int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, |
1da177e4 LT |
818 | size_t size) |
819 | { | |
3516ffb0 | 820 | struct sock *sk = sock->sk; |
1da177e4 LT |
821 | struct iovec *iov; |
822 | struct tcp_sock *tp = tcp_sk(sk); | |
823 | struct sk_buff *skb; | |
824 | int iovlen, flags; | |
c1b4a7e6 | 825 | int mss_now, size_goal; |
1da177e4 LT |
826 | int err, copied; |
827 | long timeo; | |
828 | ||
829 | lock_sock(sk); | |
830 | TCP_CHECK_TIMER(sk); | |
831 | ||
832 | flags = msg->msg_flags; | |
833 | timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); | |
834 | ||
835 | /* Wait for a connection to finish. */ | |
836 | if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) | |
837 | if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) | |
838 | goto out_err; | |
839 | ||
840 | /* This should be in poll */ | |
841 | clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
842 | ||
843 | mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); | |
c1b4a7e6 | 844 | size_goal = tp->xmit_size_goal; |
1da177e4 LT |
845 | |
846 | /* Ok commence sending. */ | |
847 | iovlen = msg->msg_iovlen; | |
848 | iov = msg->msg_iov; | |
849 | copied = 0; | |
850 | ||
851 | err = -EPIPE; | |
852 | if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) | |
853 | goto do_error; | |
854 | ||
855 | while (--iovlen >= 0) { | |
856 | int seglen = iov->iov_len; | |
857 | unsigned char __user *from = iov->iov_base; | |
858 | ||
859 | iov++; | |
860 | ||
861 | while (seglen > 0) { | |
862 | int copy; | |
863 | ||
fe067e8a | 864 | skb = tcp_write_queue_tail(sk); |
1da177e4 | 865 | |
fe067e8a | 866 | if (!tcp_send_head(sk) || |
c1b4a7e6 | 867 | (copy = size_goal - skb->len) <= 0) { |
1da177e4 LT |
868 | |
869 | new_segment: | |
870 | /* Allocate new segment. If the interface is SG, | |
871 | * allocate skb fitting to single page. | |
872 | */ | |
873 | if (!sk_stream_memory_free(sk)) | |
874 | goto wait_for_sndbuf; | |
875 | ||
df97c708 PE |
876 | skb = sk_stream_alloc_skb(sk, select_size(sk), |
877 | sk->sk_allocation); | |
1da177e4 LT |
878 | if (!skb) |
879 | goto wait_for_memory; | |
880 | ||
881 | /* | |
882 | * Check whether we can use HW checksum. | |
883 | */ | |
8648b305 | 884 | if (sk->sk_route_caps & NETIF_F_ALL_CSUM) |
84fa7933 | 885 | skb->ip_summed = CHECKSUM_PARTIAL; |
1da177e4 | 886 | |
9e412ba7 | 887 | skb_entail(sk, skb); |
c1b4a7e6 | 888 | copy = size_goal; |
1da177e4 LT |
889 | } |
890 | ||
891 | /* Try to append data to the end of skb. */ | |
892 | if (copy > seglen) | |
893 | copy = seglen; | |
894 | ||
895 | /* Where to copy to? */ | |
896 | if (skb_tailroom(skb) > 0) { | |
897 | /* We have some space in skb head. Superb! */ | |
898 | if (copy > skb_tailroom(skb)) | |
899 | copy = skb_tailroom(skb); | |
900 | if ((err = skb_add_data(skb, from, copy)) != 0) | |
901 | goto do_fault; | |
902 | } else { | |
903 | int merge = 0; | |
904 | int i = skb_shinfo(skb)->nr_frags; | |
905 | struct page *page = TCP_PAGE(sk); | |
906 | int off = TCP_OFF(sk); | |
907 | ||
908 | if (skb_can_coalesce(skb, i, page, off) && | |
909 | off != PAGE_SIZE) { | |
910 | /* We can extend the last page | |
911 | * fragment. */ | |
912 | merge = 1; | |
913 | } else if (i == MAX_SKB_FRAGS || | |
914 | (!i && | |
915 | !(sk->sk_route_caps & NETIF_F_SG))) { | |
916 | /* Need to add new fragment and cannot | |
917 | * do this because interface is non-SG, | |
918 | * or because all the page slots are | |
919 | * busy. */ | |
920 | tcp_mark_push(tp, skb); | |
921 | goto new_segment; | |
922 | } else if (page) { | |
1da177e4 LT |
923 | if (off == PAGE_SIZE) { |
924 | put_page(page); | |
925 | TCP_PAGE(sk) = page = NULL; | |
fb5f5e6e | 926 | off = 0; |
1da177e4 | 927 | } |
ef015786 | 928 | } else |
fb5f5e6e | 929 | off = 0; |
ef015786 HX |
930 | |
931 | if (copy > PAGE_SIZE - off) | |
932 | copy = PAGE_SIZE - off; | |
933 | ||
3ab224be | 934 | if (!sk_wmem_schedule(sk, copy)) |
ef015786 | 935 | goto wait_for_memory; |
1da177e4 LT |
936 | |
937 | if (!page) { | |
938 | /* Allocate new cache page. */ | |
939 | if (!(page = sk_stream_alloc_page(sk))) | |
940 | goto wait_for_memory; | |
1da177e4 LT |
941 | } |
942 | ||
1da177e4 LT |
943 | /* Time to copy data. We are close to |
944 | * the end! */ | |
945 | err = skb_copy_to_page(sk, from, skb, page, | |
946 | off, copy); | |
947 | if (err) { | |
948 | /* If this page was new, give it to the | |
949 | * socket so it does not get leaked. | |
950 | */ | |
951 | if (!TCP_PAGE(sk)) { | |
952 | TCP_PAGE(sk) = page; | |
953 | TCP_OFF(sk) = 0; | |
954 | } | |
955 | goto do_error; | |
956 | } | |
957 | ||
958 | /* Update the skb. */ | |
959 | if (merge) { | |
960 | skb_shinfo(skb)->frags[i - 1].size += | |
961 | copy; | |
962 | } else { | |
963 | skb_fill_page_desc(skb, i, page, off, copy); | |
964 | if (TCP_PAGE(sk)) { | |
965 | get_page(page); | |
966 | } else if (off + copy < PAGE_SIZE) { | |
967 | get_page(page); | |
968 | TCP_PAGE(sk) = page; | |
969 | } | |
970 | } | |
971 | ||
972 | TCP_OFF(sk) = off + copy; | |
973 | } | |
974 | ||
975 | if (!copied) | |
976 | TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_PSH; | |
977 | ||
978 | tp->write_seq += copy; | |
979 | TCP_SKB_CB(skb)->end_seq += copy; | |
7967168c | 980 | skb_shinfo(skb)->gso_segs = 0; |
1da177e4 LT |
981 | |
982 | from += copy; | |
983 | copied += copy; | |
984 | if ((seglen -= copy) == 0 && iovlen == 0) | |
985 | goto out; | |
986 | ||
69d15067 | 987 | if (skb->len < size_goal || (flags & MSG_OOB)) |
1da177e4 LT |
988 | continue; |
989 | ||
990 | if (forced_push(tp)) { | |
991 | tcp_mark_push(tp, skb); | |
9e412ba7 | 992 | __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH); |
fe067e8a | 993 | } else if (skb == tcp_send_head(sk)) |
1da177e4 LT |
994 | tcp_push_one(sk, mss_now); |
995 | continue; | |
996 | ||
997 | wait_for_sndbuf: | |
998 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
999 | wait_for_memory: | |
1000 | if (copied) | |
9e412ba7 | 1001 | tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH); |
1da177e4 LT |
1002 | |
1003 | if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) | |
1004 | goto do_error; | |
1005 | ||
1006 | mss_now = tcp_current_mss(sk, !(flags&MSG_OOB)); | |
c1b4a7e6 | 1007 | size_goal = tp->xmit_size_goal; |
1da177e4 LT |
1008 | } |
1009 | } | |
1010 | ||
1011 | out: | |
1012 | if (copied) | |
9e412ba7 | 1013 | tcp_push(sk, flags, mss_now, tp->nonagle); |
1da177e4 LT |
1014 | TCP_CHECK_TIMER(sk); |
1015 | release_sock(sk); | |
1016 | return copied; | |
1017 | ||
1018 | do_fault: | |
1019 | if (!skb->len) { | |
fe067e8a DM |
1020 | tcp_unlink_write_queue(skb, sk); |
1021 | /* It is the one place in all of TCP, except connection | |
1022 | * reset, where we can be unlinking the send_head. | |
1023 | */ | |
1024 | tcp_check_send_head(sk, skb); | |
3ab224be | 1025 | sk_wmem_free_skb(sk, skb); |
1da177e4 LT |
1026 | } |
1027 | ||
1028 | do_error: | |
1029 | if (copied) | |
1030 | goto out; | |
1031 | out_err: | |
1032 | err = sk_stream_error(sk, flags, err); | |
1033 | TCP_CHECK_TIMER(sk); | |
1034 | release_sock(sk); | |
1035 | return err; | |
1036 | } | |
1037 | ||
1038 | /* | |
1039 | * Handle reading urgent data. BSD has very simple semantics for | |
1040 | * this, no blocking and very strange errors 8) | |
1041 | */ | |
1042 | ||
1043 | static int tcp_recv_urg(struct sock *sk, long timeo, | |
1044 | struct msghdr *msg, int len, int flags, | |
1045 | int *addr_len) | |
1046 | { | |
1047 | struct tcp_sock *tp = tcp_sk(sk); | |
1048 | ||
1049 | /* No URG data to read. */ | |
1050 | if (sock_flag(sk, SOCK_URGINLINE) || !tp->urg_data || | |
1051 | tp->urg_data == TCP_URG_READ) | |
1052 | return -EINVAL; /* Yes this is right ! */ | |
1053 | ||
1054 | if (sk->sk_state == TCP_CLOSE && !sock_flag(sk, SOCK_DONE)) | |
1055 | return -ENOTCONN; | |
1056 | ||
1057 | if (tp->urg_data & TCP_URG_VALID) { | |
1058 | int err = 0; | |
1059 | char c = tp->urg_data; | |
1060 | ||
1061 | if (!(flags & MSG_PEEK)) | |
1062 | tp->urg_data = TCP_URG_READ; | |
1063 | ||
1064 | /* Read urgent data. */ | |
1065 | msg->msg_flags |= MSG_OOB; | |
1066 | ||
1067 | if (len > 0) { | |
1068 | if (!(flags & MSG_TRUNC)) | |
1069 | err = memcpy_toiovec(msg->msg_iov, &c, 1); | |
1070 | len = 1; | |
1071 | } else | |
1072 | msg->msg_flags |= MSG_TRUNC; | |
1073 | ||
1074 | return err ? -EFAULT : len; | |
1075 | } | |
1076 | ||
1077 | if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN)) | |
1078 | return 0; | |
1079 | ||
1080 | /* Fixed the recv(..., MSG_OOB) behaviour. BSD docs and | |
1081 | * the available implementations agree in this case: | |
1082 | * this call should never block, independent of the | |
1083 | * blocking state of the socket. | |
1084 | * Mike <pall@rz.uni-karlsruhe.de> | |
1085 | */ | |
1086 | return -EAGAIN; | |
1087 | } | |
1088 | ||
1089 | /* Clean up the receive buffer for full frames taken by the user, | |
1090 | * then send an ACK if necessary. COPIED is the number of bytes | |
1091 | * tcp_recvmsg has given to the user so far, it speeds up the | |
1092 | * calculation of whether or not we must ACK for the sake of | |
1093 | * a window update. | |
1094 | */ | |
0e4b4992 | 1095 | void tcp_cleanup_rbuf(struct sock *sk, int copied) |
1da177e4 LT |
1096 | { |
1097 | struct tcp_sock *tp = tcp_sk(sk); | |
1098 | int time_to_ack = 0; | |
1099 | ||
1100 | #if TCP_DEBUG | |
1101 | struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); | |
1102 | ||
547b792c | 1103 | WARN_ON(skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq)); |
1da177e4 LT |
1104 | #endif |
1105 | ||
463c84b9 ACM |
1106 | if (inet_csk_ack_scheduled(sk)) { |
1107 | const struct inet_connection_sock *icsk = inet_csk(sk); | |
1da177e4 LT |
1108 | /* Delayed ACKs frequently hit locked sockets during bulk |
1109 | * receive. */ | |
463c84b9 | 1110 | if (icsk->icsk_ack.blocked || |
1da177e4 | 1111 | /* Once-per-two-segments ACK was not sent by tcp_input.c */ |
463c84b9 | 1112 | tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss || |
1da177e4 LT |
1113 | /* |
1114 | * If this read emptied read buffer, we send ACK, if | |
1115 | * connection is not bidirectional, user drained | |
1116 | * receive buffer and there was a small segment | |
1117 | * in queue. | |
1118 | */ | |
1ef9696c AK |
1119 | (copied > 0 && |
1120 | ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) || | |
1121 | ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) && | |
1122 | !icsk->icsk_ack.pingpong)) && | |
1123 | !atomic_read(&sk->sk_rmem_alloc))) | |
1da177e4 LT |
1124 | time_to_ack = 1; |
1125 | } | |
1126 | ||
1127 | /* We send an ACK if we can now advertise a non-zero window | |
1128 | * which has been raised "significantly". | |
1129 | * | |
1130 | * Even if window raised up to infinity, do not send window open ACK | |
1131 | * in states, where we will not receive more. It is useless. | |
1132 | */ | |
1133 | if (copied > 0 && !time_to_ack && !(sk->sk_shutdown & RCV_SHUTDOWN)) { | |
1134 | __u32 rcv_window_now = tcp_receive_window(tp); | |
1135 | ||
1136 | /* Optimize, __tcp_select_window() is not cheap. */ | |
1137 | if (2*rcv_window_now <= tp->window_clamp) { | |
1138 | __u32 new_window = __tcp_select_window(sk); | |
1139 | ||
1140 | /* Send ACK now, if this read freed lots of space | |
1141 | * in our buffer. Certainly, new_window is new window. | |
1142 | * We can advertise it now, if it is not less than current one. | |
1143 | * "Lots" means "at least twice" here. | |
1144 | */ | |
1145 | if (new_window && new_window >= 2 * rcv_window_now) | |
1146 | time_to_ack = 1; | |
1147 | } | |
1148 | } | |
1149 | if (time_to_ack) | |
1150 | tcp_send_ack(sk); | |
1151 | } | |
1152 | ||
1153 | static void tcp_prequeue_process(struct sock *sk) | |
1154 | { | |
1155 | struct sk_buff *skb; | |
1156 | struct tcp_sock *tp = tcp_sk(sk); | |
1157 | ||
6f67c817 | 1158 | NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPPREQUEUED); |
1da177e4 LT |
1159 | |
1160 | /* RX process wants to run with disabled BHs, though it is not | |
1161 | * necessary */ | |
1162 | local_bh_disable(); | |
1163 | while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) | |
c57943a1 | 1164 | sk_backlog_rcv(sk, skb); |
1da177e4 LT |
1165 | local_bh_enable(); |
1166 | ||
1167 | /* Clear memory counter. */ | |
1168 | tp->ucopy.memory = 0; | |
1169 | } | |
1170 | ||
1171 | static inline struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off) | |
1172 | { | |
1173 | struct sk_buff *skb; | |
1174 | u32 offset; | |
1175 | ||
1176 | skb_queue_walk(&sk->sk_receive_queue, skb) { | |
1177 | offset = seq - TCP_SKB_CB(skb)->seq; | |
aa8223c7 | 1178 | if (tcp_hdr(skb)->syn) |
1da177e4 | 1179 | offset--; |
aa8223c7 | 1180 | if (offset < skb->len || tcp_hdr(skb)->fin) { |
1da177e4 LT |
1181 | *off = offset; |
1182 | return skb; | |
1183 | } | |
1184 | } | |
1185 | return NULL; | |
1186 | } | |
1187 | ||
1188 | /* | |
1189 | * This routine provides an alternative to tcp_recvmsg() for routines | |
1190 | * that would like to handle copying from skbuffs directly in 'sendfile' | |
1191 | * fashion. | |
1192 | * Note: | |
1193 | * - It is assumed that the socket was locked by the caller. | |
1194 | * - The routine does not block. | |
1195 | * - At present, there is no support for reading OOB data | |
1196 | * or for 'peeking' the socket using this routine | |
1197 | * (although both would be easy to implement). | |
1198 | */ | |
1199 | int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, | |
1200 | sk_read_actor_t recv_actor) | |
1201 | { | |
1202 | struct sk_buff *skb; | |
1203 | struct tcp_sock *tp = tcp_sk(sk); | |
1204 | u32 seq = tp->copied_seq; | |
1205 | u32 offset; | |
1206 | int copied = 0; | |
1207 | ||
1208 | if (sk->sk_state == TCP_LISTEN) | |
1209 | return -ENOTCONN; | |
1210 | while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) { | |
1211 | if (offset < skb->len) { | |
374e7b59 OP |
1212 | int used; |
1213 | size_t len; | |
1da177e4 LT |
1214 | |
1215 | len = skb->len - offset; | |
1216 | /* Stop reading if we hit a patch of urgent data */ | |
1217 | if (tp->urg_data) { | |
1218 | u32 urg_offset = tp->urg_seq - seq; | |
1219 | if (urg_offset < len) | |
1220 | len = urg_offset; | |
1221 | if (!len) | |
1222 | break; | |
1223 | } | |
1224 | used = recv_actor(desc, skb, offset, len); | |
ddb61a57 JA |
1225 | if (used < 0) { |
1226 | if (!copied) | |
1227 | copied = used; | |
1228 | break; | |
1229 | } else if (used <= len) { | |
1da177e4 LT |
1230 | seq += used; |
1231 | copied += used; | |
1232 | offset += used; | |
1233 | } | |
293ad604 OP |
1234 | /* |
1235 | * If recv_actor drops the lock (e.g. TCP splice | |
1236 | * receive) the skb pointer might be invalid when | |
1237 | * getting here: tcp_collapse might have deleted it | |
1238 | * while aggregating skbs from the socket queue. | |
1239 | */ | |
1240 | skb = tcp_recv_skb(sk, seq-1, &offset); | |
1241 | if (!skb || (offset+1 != skb->len)) | |
1da177e4 LT |
1242 | break; |
1243 | } | |
aa8223c7 | 1244 | if (tcp_hdr(skb)->fin) { |
624d1164 | 1245 | sk_eat_skb(sk, skb, 0); |
1da177e4 LT |
1246 | ++seq; |
1247 | break; | |
1248 | } | |
624d1164 | 1249 | sk_eat_skb(sk, skb, 0); |
1da177e4 LT |
1250 | if (!desc->count) |
1251 | break; | |
1252 | } | |
1253 | tp->copied_seq = seq; | |
1254 | ||
1255 | tcp_rcv_space_adjust(sk); | |
1256 | ||
1257 | /* Clean up data we have read: This will do ACK frames. */ | |
ddb61a57 | 1258 | if (copied > 0) |
0e4b4992 | 1259 | tcp_cleanup_rbuf(sk, copied); |
1da177e4 LT |
1260 | return copied; |
1261 | } | |
1262 | ||
1263 | /* | |
1264 | * This routine copies from a sock struct into the user buffer. | |
1265 | * | |
1266 | * Technical note: in 2.3 we work on _locked_ socket, so that | |
1267 | * tricks with *seq access order and skb->users are not required. | |
1268 | * Probably, code can be easily improved even more. | |
1269 | */ | |
1270 | ||
1271 | int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, | |
1272 | size_t len, int nonblock, int flags, int *addr_len) | |
1273 | { | |
1274 | struct tcp_sock *tp = tcp_sk(sk); | |
1275 | int copied = 0; | |
1276 | u32 peek_seq; | |
1277 | u32 *seq; | |
1278 | unsigned long used; | |
1279 | int err; | |
1280 | int target; /* Read at least this many bytes */ | |
1281 | long timeo; | |
1282 | struct task_struct *user_recv = NULL; | |
1a2449a8 | 1283 | int copied_early = 0; |
2b1244a4 | 1284 | struct sk_buff *skb; |
1da177e4 LT |
1285 | |
1286 | lock_sock(sk); | |
1287 | ||
1288 | TCP_CHECK_TIMER(sk); | |
1289 | ||
1290 | err = -ENOTCONN; | |
1291 | if (sk->sk_state == TCP_LISTEN) | |
1292 | goto out; | |
1293 | ||
1294 | timeo = sock_rcvtimeo(sk, nonblock); | |
1295 | ||
1296 | /* Urgent data needs to be handled specially. */ | |
1297 | if (flags & MSG_OOB) | |
1298 | goto recv_urg; | |
1299 | ||
1300 | seq = &tp->copied_seq; | |
1301 | if (flags & MSG_PEEK) { | |
1302 | peek_seq = tp->copied_seq; | |
1303 | seq = &peek_seq; | |
1304 | } | |
1305 | ||
1306 | target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); | |
1307 | ||
1a2449a8 CL |
1308 | #ifdef CONFIG_NET_DMA |
1309 | tp->ucopy.dma_chan = NULL; | |
1310 | preempt_disable(); | |
2b1244a4 | 1311 | skb = skb_peek_tail(&sk->sk_receive_queue); |
e00c5d8b AM |
1312 | { |
1313 | int available = 0; | |
1314 | ||
1315 | if (skb) | |
1316 | available = TCP_SKB_CB(skb)->seq + skb->len - (*seq); | |
1317 | if ((available < target) && | |
1318 | (len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) && | |
1319 | !sysctl_tcp_low_latency && | |
1320 | __get_cpu_var(softnet_data).net_dma) { | |
1321 | preempt_enable_no_resched(); | |
1322 | tp->ucopy.pinned_list = | |
1323 | dma_pin_iovec_pages(msg->msg_iov, len); | |
1324 | } else { | |
1325 | preempt_enable_no_resched(); | |
1326 | } | |
1327 | } | |
1a2449a8 CL |
1328 | #endif |
1329 | ||
1da177e4 | 1330 | do { |
1da177e4 LT |
1331 | u32 offset; |
1332 | ||
1333 | /* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */ | |
1334 | if (tp->urg_data && tp->urg_seq == *seq) { | |
1335 | if (copied) | |
1336 | break; | |
1337 | if (signal_pending(current)) { | |
1338 | copied = timeo ? sock_intr_errno(timeo) : -EAGAIN; | |
1339 | break; | |
1340 | } | |
1341 | } | |
1342 | ||
1343 | /* Next get a buffer. */ | |
1344 | ||
1345 | skb = skb_peek(&sk->sk_receive_queue); | |
1346 | do { | |
1347 | if (!skb) | |
1348 | break; | |
1349 | ||
1350 | /* Now that we have two receive queues this | |
1351 | * shouldn't happen. | |
1352 | */ | |
1353 | if (before(*seq, TCP_SKB_CB(skb)->seq)) { | |
1354 | printk(KERN_INFO "recvmsg bug: copied %X " | |
1355 | "seq %X\n", *seq, TCP_SKB_CB(skb)->seq); | |
1356 | break; | |
1357 | } | |
1358 | offset = *seq - TCP_SKB_CB(skb)->seq; | |
aa8223c7 | 1359 | if (tcp_hdr(skb)->syn) |
1da177e4 LT |
1360 | offset--; |
1361 | if (offset < skb->len) | |
1362 | goto found_ok_skb; | |
aa8223c7 | 1363 | if (tcp_hdr(skb)->fin) |
1da177e4 | 1364 | goto found_fin_ok; |
547b792c | 1365 | WARN_ON(!(flags & MSG_PEEK)); |
1da177e4 LT |
1366 | skb = skb->next; |
1367 | } while (skb != (struct sk_buff *)&sk->sk_receive_queue); | |
1368 | ||
1369 | /* Well, if we have backlog, try to process it now yet. */ | |
1370 | ||
1371 | if (copied >= target && !sk->sk_backlog.tail) | |
1372 | break; | |
1373 | ||
1374 | if (copied) { | |
1375 | if (sk->sk_err || | |
1376 | sk->sk_state == TCP_CLOSE || | |
1377 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1378 | !timeo || | |
518a09ef | 1379 | signal_pending(current)) |
1da177e4 LT |
1380 | break; |
1381 | } else { | |
1382 | if (sock_flag(sk, SOCK_DONE)) | |
1383 | break; | |
1384 | ||
1385 | if (sk->sk_err) { | |
1386 | copied = sock_error(sk); | |
1387 | break; | |
1388 | } | |
1389 | ||
1390 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
1391 | break; | |
1392 | ||
1393 | if (sk->sk_state == TCP_CLOSE) { | |
1394 | if (!sock_flag(sk, SOCK_DONE)) { | |
1395 | /* This occurs when user tries to read | |
1396 | * from never connected socket. | |
1397 | */ | |
1398 | copied = -ENOTCONN; | |
1399 | break; | |
1400 | } | |
1401 | break; | |
1402 | } | |
1403 | ||
1404 | if (!timeo) { | |
1405 | copied = -EAGAIN; | |
1406 | break; | |
1407 | } | |
1408 | ||
1409 | if (signal_pending(current)) { | |
1410 | copied = sock_intr_errno(timeo); | |
1411 | break; | |
1412 | } | |
1413 | } | |
1414 | ||
0e4b4992 | 1415 | tcp_cleanup_rbuf(sk, copied); |
1da177e4 | 1416 | |
7df55125 | 1417 | if (!sysctl_tcp_low_latency && tp->ucopy.task == user_recv) { |
1da177e4 LT |
1418 | /* Install new reader */ |
1419 | if (!user_recv && !(flags & (MSG_TRUNC | MSG_PEEK))) { | |
1420 | user_recv = current; | |
1421 | tp->ucopy.task = user_recv; | |
1422 | tp->ucopy.iov = msg->msg_iov; | |
1423 | } | |
1424 | ||
1425 | tp->ucopy.len = len; | |
1426 | ||
547b792c IJ |
1427 | WARN_ON(tp->copied_seq != tp->rcv_nxt && |
1428 | !(flags & (MSG_PEEK | MSG_TRUNC))); | |
1da177e4 LT |
1429 | |
1430 | /* Ugly... If prequeue is not empty, we have to | |
1431 | * process it before releasing socket, otherwise | |
1432 | * order will be broken at second iteration. | |
1433 | * More elegant solution is required!!! | |
1434 | * | |
1435 | * Look: we have the following (pseudo)queues: | |
1436 | * | |
1437 | * 1. packets in flight | |
1438 | * 2. backlog | |
1439 | * 3. prequeue | |
1440 | * 4. receive_queue | |
1441 | * | |
1442 | * Each queue can be processed only if the next ones | |
1443 | * are empty. At this point we have empty receive_queue. | |
1444 | * But prequeue _can_ be not empty after 2nd iteration, | |
1445 | * when we jumped to start of loop because backlog | |
1446 | * processing added something to receive_queue. | |
1447 | * We cannot release_sock(), because backlog contains | |
1448 | * packets arrived _after_ prequeued ones. | |
1449 | * | |
1450 | * Shortly, algorithm is clear --- to process all | |
1451 | * the queues in order. We could make it more directly, | |
1452 | * requeueing packets from backlog to prequeue, if | |
1453 | * is not empty. It is more elegant, but eats cycles, | |
1454 | * unfortunately. | |
1455 | */ | |
b03efcfb | 1456 | if (!skb_queue_empty(&tp->ucopy.prequeue)) |
1da177e4 LT |
1457 | goto do_prequeue; |
1458 | ||
1459 | /* __ Set realtime policy in scheduler __ */ | |
1460 | } | |
1461 | ||
1462 | if (copied >= target) { | |
1463 | /* Do not sleep, just process backlog. */ | |
1464 | release_sock(sk); | |
1465 | lock_sock(sk); | |
1466 | } else | |
1467 | sk_wait_data(sk, &timeo); | |
1468 | ||
1a2449a8 CL |
1469 | #ifdef CONFIG_NET_DMA |
1470 | tp->ucopy.wakeup = 0; | |
1471 | #endif | |
1472 | ||
1da177e4 LT |
1473 | if (user_recv) { |
1474 | int chunk; | |
1475 | ||
1476 | /* __ Restore normal policy in scheduler __ */ | |
1477 | ||
1478 | if ((chunk = len - tp->ucopy.len) != 0) { | |
ed88098e | 1479 | NET_ADD_STATS_USER(sock_net(sk), LINUX_MIB_TCPDIRECTCOPYFROMBACKLOG, chunk); |
1da177e4 LT |
1480 | len -= chunk; |
1481 | copied += chunk; | |
1482 | } | |
1483 | ||
1484 | if (tp->rcv_nxt == tp->copied_seq && | |
b03efcfb | 1485 | !skb_queue_empty(&tp->ucopy.prequeue)) { |
1da177e4 LT |
1486 | do_prequeue: |
1487 | tcp_prequeue_process(sk); | |
1488 | ||
1489 | if ((chunk = len - tp->ucopy.len) != 0) { | |
ed88098e | 1490 | NET_ADD_STATS_USER(sock_net(sk), LINUX_MIB_TCPDIRECTCOPYFROMPREQUEUE, chunk); |
1da177e4 LT |
1491 | len -= chunk; |
1492 | copied += chunk; | |
1493 | } | |
1494 | } | |
1495 | } | |
1496 | if ((flags & MSG_PEEK) && peek_seq != tp->copied_seq) { | |
1497 | if (net_ratelimit()) | |
1498 | printk(KERN_DEBUG "TCP(%s:%d): Application bug, race in MSG_PEEK.\n", | |
ba25f9dc | 1499 | current->comm, task_pid_nr(current)); |
1da177e4 LT |
1500 | peek_seq = tp->copied_seq; |
1501 | } | |
1502 | continue; | |
1503 | ||
1504 | found_ok_skb: | |
1505 | /* Ok so how much can we use? */ | |
1506 | used = skb->len - offset; | |
1507 | if (len < used) | |
1508 | used = len; | |
1509 | ||
1510 | /* Do we have urgent data here? */ | |
1511 | if (tp->urg_data) { | |
1512 | u32 urg_offset = tp->urg_seq - *seq; | |
1513 | if (urg_offset < used) { | |
1514 | if (!urg_offset) { | |
1515 | if (!sock_flag(sk, SOCK_URGINLINE)) { | |
1516 | ++*seq; | |
1517 | offset++; | |
1518 | used--; | |
1519 | if (!used) | |
1520 | goto skip_copy; | |
1521 | } | |
1522 | } else | |
1523 | used = urg_offset; | |
1524 | } | |
1525 | } | |
1526 | ||
1527 | if (!(flags & MSG_TRUNC)) { | |
1a2449a8 CL |
1528 | #ifdef CONFIG_NET_DMA |
1529 | if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) | |
1530 | tp->ucopy.dma_chan = get_softnet_dma(); | |
1531 | ||
1532 | if (tp->ucopy.dma_chan) { | |
1533 | tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec( | |
1534 | tp->ucopy.dma_chan, skb, offset, | |
1535 | msg->msg_iov, used, | |
1536 | tp->ucopy.pinned_list); | |
1537 | ||
1538 | if (tp->ucopy.dma_cookie < 0) { | |
1539 | ||
1540 | printk(KERN_ALERT "dma_cookie < 0\n"); | |
1541 | ||
1542 | /* Exception. Bailout! */ | |
1543 | if (!copied) | |
1544 | copied = -EFAULT; | |
1545 | break; | |
1546 | } | |
1547 | if ((offset + used) == skb->len) | |
1548 | copied_early = 1; | |
1549 | ||
1550 | } else | |
1551 | #endif | |
1552 | { | |
1553 | err = skb_copy_datagram_iovec(skb, offset, | |
1554 | msg->msg_iov, used); | |
1555 | if (err) { | |
1556 | /* Exception. Bailout! */ | |
1557 | if (!copied) | |
1558 | copied = -EFAULT; | |
1559 | break; | |
1560 | } | |
1da177e4 LT |
1561 | } |
1562 | } | |
1563 | ||
1564 | *seq += used; | |
1565 | copied += used; | |
1566 | len -= used; | |
1567 | ||
1568 | tcp_rcv_space_adjust(sk); | |
1569 | ||
1570 | skip_copy: | |
1571 | if (tp->urg_data && after(tp->copied_seq, tp->urg_seq)) { | |
1572 | tp->urg_data = 0; | |
9e412ba7 | 1573 | tcp_fast_path_check(sk); |
1da177e4 LT |
1574 | } |
1575 | if (used + offset < skb->len) | |
1576 | continue; | |
1577 | ||
aa8223c7 | 1578 | if (tcp_hdr(skb)->fin) |
1da177e4 | 1579 | goto found_fin_ok; |
1a2449a8 CL |
1580 | if (!(flags & MSG_PEEK)) { |
1581 | sk_eat_skb(sk, skb, copied_early); | |
1582 | copied_early = 0; | |
1583 | } | |
1da177e4 LT |
1584 | continue; |
1585 | ||
1586 | found_fin_ok: | |
1587 | /* Process the FIN. */ | |
1588 | ++*seq; | |
1a2449a8 CL |
1589 | if (!(flags & MSG_PEEK)) { |
1590 | sk_eat_skb(sk, skb, copied_early); | |
1591 | copied_early = 0; | |
1592 | } | |
1da177e4 LT |
1593 | break; |
1594 | } while (len > 0); | |
1595 | ||
1596 | if (user_recv) { | |
b03efcfb | 1597 | if (!skb_queue_empty(&tp->ucopy.prequeue)) { |
1da177e4 LT |
1598 | int chunk; |
1599 | ||
1600 | tp->ucopy.len = copied > 0 ? len : 0; | |
1601 | ||
1602 | tcp_prequeue_process(sk); | |
1603 | ||
1604 | if (copied > 0 && (chunk = len - tp->ucopy.len) != 0) { | |
ed88098e | 1605 | NET_ADD_STATS_USER(sock_net(sk), LINUX_MIB_TCPDIRECTCOPYFROMPREQUEUE, chunk); |
1da177e4 LT |
1606 | len -= chunk; |
1607 | copied += chunk; | |
1608 | } | |
1609 | } | |
1610 | ||
1611 | tp->ucopy.task = NULL; | |
1612 | tp->ucopy.len = 0; | |
1613 | } | |
1614 | ||
1a2449a8 CL |
1615 | #ifdef CONFIG_NET_DMA |
1616 | if (tp->ucopy.dma_chan) { | |
1a2449a8 CL |
1617 | dma_cookie_t done, used; |
1618 | ||
1619 | dma_async_memcpy_issue_pending(tp->ucopy.dma_chan); | |
1620 | ||
1621 | while (dma_async_memcpy_complete(tp->ucopy.dma_chan, | |
e905a9ed YH |
1622 | tp->ucopy.dma_cookie, &done, |
1623 | &used) == DMA_IN_PROGRESS) { | |
1a2449a8 CL |
1624 | /* do partial cleanup of sk_async_wait_queue */ |
1625 | while ((skb = skb_peek(&sk->sk_async_wait_queue)) && | |
1626 | (dma_async_is_complete(skb->dma_cookie, done, | |
e905a9ed | 1627 | used) == DMA_SUCCESS)) { |
1a2449a8 CL |
1628 | __skb_dequeue(&sk->sk_async_wait_queue); |
1629 | kfree_skb(skb); | |
1630 | } | |
1631 | } | |
1632 | ||
1633 | /* Safe to free early-copied skbs now */ | |
1634 | __skb_queue_purge(&sk->sk_async_wait_queue); | |
1635 | dma_chan_put(tp->ucopy.dma_chan); | |
1636 | tp->ucopy.dma_chan = NULL; | |
1637 | } | |
1638 | if (tp->ucopy.pinned_list) { | |
1639 | dma_unpin_iovec_pages(tp->ucopy.pinned_list); | |
1640 | tp->ucopy.pinned_list = NULL; | |
1641 | } | |
1642 | #endif | |
1643 | ||
1da177e4 LT |
1644 | /* According to UNIX98, msg_name/msg_namelen are ignored |
1645 | * on connected socket. I was just happy when found this 8) --ANK | |
1646 | */ | |
1647 | ||
1648 | /* Clean up data we have read: This will do ACK frames. */ | |
0e4b4992 | 1649 | tcp_cleanup_rbuf(sk, copied); |
1da177e4 LT |
1650 | |
1651 | TCP_CHECK_TIMER(sk); | |
1652 | release_sock(sk); | |
1653 | return copied; | |
1654 | ||
1655 | out: | |
1656 | TCP_CHECK_TIMER(sk); | |
1657 | release_sock(sk); | |
1658 | return err; | |
1659 | ||
1660 | recv_urg: | |
1661 | err = tcp_recv_urg(sk, timeo, msg, len, flags, addr_len); | |
1662 | goto out; | |
1663 | } | |
1664 | ||
490d5046 IJ |
1665 | void tcp_set_state(struct sock *sk, int state) |
1666 | { | |
1667 | int oldstate = sk->sk_state; | |
1668 | ||
1669 | switch (state) { | |
1670 | case TCP_ESTABLISHED: | |
1671 | if (oldstate != TCP_ESTABLISHED) | |
81cc8a75 | 1672 | TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); |
490d5046 IJ |
1673 | break; |
1674 | ||
1675 | case TCP_CLOSE: | |
1676 | if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED) | |
81cc8a75 | 1677 | TCP_INC_STATS(sock_net(sk), TCP_MIB_ESTABRESETS); |
490d5046 IJ |
1678 | |
1679 | sk->sk_prot->unhash(sk); | |
1680 | if (inet_csk(sk)->icsk_bind_hash && | |
1681 | !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) | |
ab1e0a13 | 1682 | inet_put_port(sk); |
490d5046 IJ |
1683 | /* fall through */ |
1684 | default: | |
5a5f3a8d | 1685 | if (oldstate == TCP_ESTABLISHED) |
74688e48 | 1686 | TCP_DEC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); |
490d5046 IJ |
1687 | } |
1688 | ||
1689 | /* Change state AFTER socket is unhashed to avoid closed | |
1690 | * socket sitting in hash tables. | |
1691 | */ | |
1692 | sk->sk_state = state; | |
1693 | ||
1694 | #ifdef STATE_TRACE | |
5a5f3a8d | 1695 | SOCK_DEBUG(sk, "TCP sk=%p, State %s -> %s\n", sk, statename[oldstate], statename[state]); |
490d5046 IJ |
1696 | #endif |
1697 | } | |
1698 | EXPORT_SYMBOL_GPL(tcp_set_state); | |
1699 | ||
1da177e4 LT |
1700 | /* |
1701 | * State processing on a close. This implements the state shift for | |
1702 | * sending our FIN frame. Note that we only send a FIN for some | |
1703 | * states. A shutdown() may have already sent the FIN, or we may be | |
1704 | * closed. | |
1705 | */ | |
1706 | ||
9b5b5cff | 1707 | static const unsigned char new_state[16] = { |
1da177e4 LT |
1708 | /* current state: new state: action: */ |
1709 | /* (Invalid) */ TCP_CLOSE, | |
1710 | /* TCP_ESTABLISHED */ TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
1711 | /* TCP_SYN_SENT */ TCP_CLOSE, | |
1712 | /* TCP_SYN_RECV */ TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
1713 | /* TCP_FIN_WAIT1 */ TCP_FIN_WAIT1, | |
1714 | /* TCP_FIN_WAIT2 */ TCP_FIN_WAIT2, | |
1715 | /* TCP_TIME_WAIT */ TCP_CLOSE, | |
1716 | /* TCP_CLOSE */ TCP_CLOSE, | |
1717 | /* TCP_CLOSE_WAIT */ TCP_LAST_ACK | TCP_ACTION_FIN, | |
1718 | /* TCP_LAST_ACK */ TCP_LAST_ACK, | |
1719 | /* TCP_LISTEN */ TCP_CLOSE, | |
1720 | /* TCP_CLOSING */ TCP_CLOSING, | |
1721 | }; | |
1722 | ||
1723 | static int tcp_close_state(struct sock *sk) | |
1724 | { | |
1725 | int next = (int)new_state[sk->sk_state]; | |
1726 | int ns = next & TCP_STATE_MASK; | |
1727 | ||
1728 | tcp_set_state(sk, ns); | |
1729 | ||
1730 | return next & TCP_ACTION_FIN; | |
1731 | } | |
1732 | ||
1733 | /* | |
1734 | * Shutdown the sending side of a connection. Much like close except | |
1f29b058 | 1735 | * that we don't receive shut down or sock_set_flag(sk, SOCK_DEAD). |
1da177e4 LT |
1736 | */ |
1737 | ||
1738 | void tcp_shutdown(struct sock *sk, int how) | |
1739 | { | |
1740 | /* We need to grab some memory, and put together a FIN, | |
1741 | * and then put it into the queue to be sent. | |
1742 | * Tim MacKenzie(tym@dibbler.cs.monash.edu.au) 4 Dec '92. | |
1743 | */ | |
1744 | if (!(how & SEND_SHUTDOWN)) | |
1745 | return; | |
1746 | ||
1747 | /* If we've already sent a FIN, or it's a closed state, skip this. */ | |
1748 | if ((1 << sk->sk_state) & | |
1749 | (TCPF_ESTABLISHED | TCPF_SYN_SENT | | |
1750 | TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) { | |
1751 | /* Clear out any half completed packets. FIN if needed. */ | |
1752 | if (tcp_close_state(sk)) | |
1753 | tcp_send_fin(sk); | |
1754 | } | |
1755 | } | |
1756 | ||
1da177e4 LT |
1757 | void tcp_close(struct sock *sk, long timeout) |
1758 | { | |
1759 | struct sk_buff *skb; | |
1760 | int data_was_unread = 0; | |
75c2d907 | 1761 | int state; |
1da177e4 LT |
1762 | |
1763 | lock_sock(sk); | |
1764 | sk->sk_shutdown = SHUTDOWN_MASK; | |
1765 | ||
1766 | if (sk->sk_state == TCP_LISTEN) { | |
1767 | tcp_set_state(sk, TCP_CLOSE); | |
1768 | ||
1769 | /* Special case. */ | |
0a5578cf | 1770 | inet_csk_listen_stop(sk); |
1da177e4 LT |
1771 | |
1772 | goto adjudge_to_death; | |
1773 | } | |
1774 | ||
1775 | /* We need to flush the recv. buffs. We do this only on the | |
1776 | * descriptor close, not protocol-sourced closes, because the | |
1777 | * reader process may not have drained the data yet! | |
1778 | */ | |
1779 | while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { | |
1780 | u32 len = TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq - | |
aa8223c7 | 1781 | tcp_hdr(skb)->fin; |
1da177e4 LT |
1782 | data_was_unread += len; |
1783 | __kfree_skb(skb); | |
1784 | } | |
1785 | ||
3ab224be | 1786 | sk_mem_reclaim(sk); |
1da177e4 | 1787 | |
65bb723c GR |
1788 | /* As outlined in RFC 2525, section 2.17, we send a RST here because |
1789 | * data was lost. To witness the awful effects of the old behavior of | |
1790 | * always doing a FIN, run an older 2.1.x kernel or 2.0.x, start a bulk | |
1791 | * GET in an FTP client, suspend the process, wait for the client to | |
1792 | * advertise a zero window, then kill -9 the FTP client, wheee... | |
1793 | * Note: timeout is always zero in such a case. | |
1da177e4 LT |
1794 | */ |
1795 | if (data_was_unread) { | |
1796 | /* Unread data was tossed, zap the connection. */ | |
6f67c817 | 1797 | NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE); |
1da177e4 LT |
1798 | tcp_set_state(sk, TCP_CLOSE); |
1799 | tcp_send_active_reset(sk, GFP_KERNEL); | |
1800 | } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { | |
1801 | /* Check zero linger _after_ checking for unread data. */ | |
1802 | sk->sk_prot->disconnect(sk, 0); | |
6f67c817 | 1803 | NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPABORTONDATA); |
1da177e4 LT |
1804 | } else if (tcp_close_state(sk)) { |
1805 | /* We FIN if the application ate all the data before | |
1806 | * zapping the connection. | |
1807 | */ | |
1808 | ||
1809 | /* RED-PEN. Formally speaking, we have broken TCP state | |
1810 | * machine. State transitions: | |
1811 | * | |
1812 | * TCP_ESTABLISHED -> TCP_FIN_WAIT1 | |
1813 | * TCP_SYN_RECV -> TCP_FIN_WAIT1 (forget it, it's impossible) | |
1814 | * TCP_CLOSE_WAIT -> TCP_LAST_ACK | |
1815 | * | |
1816 | * are legal only when FIN has been sent (i.e. in window), | |
1817 | * rather than queued out of window. Purists blame. | |
1818 | * | |
1819 | * F.e. "RFC state" is ESTABLISHED, | |
1820 | * if Linux state is FIN-WAIT-1, but FIN is still not sent. | |
1821 | * | |
1822 | * The visible declinations are that sometimes | |
1823 | * we enter time-wait state, when it is not required really | |
1824 | * (harmless), do not send active resets, when they are | |
1825 | * required by specs (TCP_ESTABLISHED, TCP_CLOSE_WAIT, when | |
1826 | * they look as CLOSING or LAST_ACK for Linux) | |
1827 | * Probably, I missed some more holelets. | |
1828 | * --ANK | |
1829 | */ | |
1830 | tcp_send_fin(sk); | |
1831 | } | |
1832 | ||
1833 | sk_stream_wait_close(sk, timeout); | |
1834 | ||
1835 | adjudge_to_death: | |
75c2d907 HX |
1836 | state = sk->sk_state; |
1837 | sock_hold(sk); | |
1838 | sock_orphan(sk); | |
dd24c001 | 1839 | percpu_counter_inc(sk->sk_prot->orphan_count); |
75c2d907 | 1840 | |
1da177e4 LT |
1841 | /* It is the last release_sock in its life. It will remove backlog. */ |
1842 | release_sock(sk); | |
1843 | ||
1844 | ||
1845 | /* Now socket is owned by kernel and we acquire BH lock | |
1846 | to finish close. No need to check for user refs. | |
1847 | */ | |
1848 | local_bh_disable(); | |
1849 | bh_lock_sock(sk); | |
547b792c | 1850 | WARN_ON(sock_owned_by_user(sk)); |
1da177e4 | 1851 | |
75c2d907 HX |
1852 | /* Have we already been destroyed by a softirq or backlog? */ |
1853 | if (state != TCP_CLOSE && sk->sk_state == TCP_CLOSE) | |
1854 | goto out; | |
1da177e4 LT |
1855 | |
1856 | /* This is a (useful) BSD violating of the RFC. There is a | |
1857 | * problem with TCP as specified in that the other end could | |
1858 | * keep a socket open forever with no application left this end. | |
1859 | * We use a 3 minute timeout (about the same as BSD) then kill | |
1860 | * our end. If they send after that then tough - BUT: long enough | |
1861 | * that we won't make the old 4*rto = almost no time - whoops | |
1862 | * reset mistake. | |
1863 | * | |
1864 | * Nope, it was not mistake. It is really desired behaviour | |
1865 | * f.e. on http servers, when such sockets are useless, but | |
1866 | * consume significant resources. Let's do it with special | |
1867 | * linger2 option. --ANK | |
1868 | */ | |
1869 | ||
1870 | if (sk->sk_state == TCP_FIN_WAIT2) { | |
1871 | struct tcp_sock *tp = tcp_sk(sk); | |
1872 | if (tp->linger2 < 0) { | |
1873 | tcp_set_state(sk, TCP_CLOSE); | |
1874 | tcp_send_active_reset(sk, GFP_ATOMIC); | |
de0744af PE |
1875 | NET_INC_STATS_BH(sock_net(sk), |
1876 | LINUX_MIB_TCPABORTONLINGER); | |
1da177e4 | 1877 | } else { |
463c84b9 | 1878 | const int tmo = tcp_fin_time(sk); |
1da177e4 LT |
1879 | |
1880 | if (tmo > TCP_TIMEWAIT_LEN) { | |
52499afe DM |
1881 | inet_csk_reset_keepalive_timer(sk, |
1882 | tmo - TCP_TIMEWAIT_LEN); | |
1da177e4 | 1883 | } else { |
1da177e4 LT |
1884 | tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); |
1885 | goto out; | |
1886 | } | |
1887 | } | |
1888 | } | |
1889 | if (sk->sk_state != TCP_CLOSE) { | |
dd24c001 ED |
1890 | int orphan_count = percpu_counter_read_positive( |
1891 | sk->sk_prot->orphan_count); | |
1892 | ||
3ab224be | 1893 | sk_mem_reclaim(sk); |
dd24c001 | 1894 | if (tcp_too_many_orphans(sk, orphan_count)) { |
1da177e4 LT |
1895 | if (net_ratelimit()) |
1896 | printk(KERN_INFO "TCP: too many of orphaned " | |
1897 | "sockets\n"); | |
1898 | tcp_set_state(sk, TCP_CLOSE); | |
1899 | tcp_send_active_reset(sk, GFP_ATOMIC); | |
de0744af PE |
1900 | NET_INC_STATS_BH(sock_net(sk), |
1901 | LINUX_MIB_TCPABORTONMEMORY); | |
1da177e4 LT |
1902 | } |
1903 | } | |
1da177e4 LT |
1904 | |
1905 | if (sk->sk_state == TCP_CLOSE) | |
0a5578cf | 1906 | inet_csk_destroy_sock(sk); |
1da177e4 LT |
1907 | /* Otherwise, socket is reprieved until protocol close. */ |
1908 | ||
1909 | out: | |
1910 | bh_unlock_sock(sk); | |
1911 | local_bh_enable(); | |
1912 | sock_put(sk); | |
1913 | } | |
1914 | ||
1915 | /* These states need RST on ABORT according to RFC793 */ | |
1916 | ||
1917 | static inline int tcp_need_reset(int state) | |
1918 | { | |
1919 | return (1 << state) & | |
1920 | (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 | | |
1921 | TCPF_FIN_WAIT2 | TCPF_SYN_RECV); | |
1922 | } | |
1923 | ||
1924 | int tcp_disconnect(struct sock *sk, int flags) | |
1925 | { | |
1926 | struct inet_sock *inet = inet_sk(sk); | |
463c84b9 | 1927 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
1928 | struct tcp_sock *tp = tcp_sk(sk); |
1929 | int err = 0; | |
1930 | int old_state = sk->sk_state; | |
1931 | ||
1932 | if (old_state != TCP_CLOSE) | |
1933 | tcp_set_state(sk, TCP_CLOSE); | |
1934 | ||
1935 | /* ABORT function of RFC793 */ | |
1936 | if (old_state == TCP_LISTEN) { | |
0a5578cf | 1937 | inet_csk_listen_stop(sk); |
1da177e4 LT |
1938 | } else if (tcp_need_reset(old_state) || |
1939 | (tp->snd_nxt != tp->write_seq && | |
1940 | (1 << old_state) & (TCPF_CLOSING | TCPF_LAST_ACK))) { | |
caa20d9a | 1941 | /* The last check adjusts for discrepancy of Linux wrt. RFC |
1da177e4 LT |
1942 | * states |
1943 | */ | |
1944 | tcp_send_active_reset(sk, gfp_any()); | |
1945 | sk->sk_err = ECONNRESET; | |
1946 | } else if (old_state == TCP_SYN_SENT) | |
1947 | sk->sk_err = ECONNRESET; | |
1948 | ||
1949 | tcp_clear_xmit_timers(sk); | |
1950 | __skb_queue_purge(&sk->sk_receive_queue); | |
fe067e8a | 1951 | tcp_write_queue_purge(sk); |
1da177e4 | 1952 | __skb_queue_purge(&tp->out_of_order_queue); |
1a2449a8 CL |
1953 | #ifdef CONFIG_NET_DMA |
1954 | __skb_queue_purge(&sk->sk_async_wait_queue); | |
1955 | #endif | |
1da177e4 LT |
1956 | |
1957 | inet->dport = 0; | |
1958 | ||
1959 | if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) | |
1960 | inet_reset_saddr(sk); | |
1961 | ||
1962 | sk->sk_shutdown = 0; | |
1963 | sock_reset_flag(sk, SOCK_DONE); | |
1964 | tp->srtt = 0; | |
1965 | if ((tp->write_seq += tp->max_window + 2) == 0) | |
1966 | tp->write_seq = 1; | |
463c84b9 | 1967 | icsk->icsk_backoff = 0; |
1da177e4 | 1968 | tp->snd_cwnd = 2; |
6687e988 | 1969 | icsk->icsk_probes_out = 0; |
1da177e4 LT |
1970 | tp->packets_out = 0; |
1971 | tp->snd_ssthresh = 0x7fffffff; | |
1972 | tp->snd_cwnd_cnt = 0; | |
9772efb9 | 1973 | tp->bytes_acked = 0; |
6687e988 | 1974 | tcp_set_ca_state(sk, TCP_CA_Open); |
1da177e4 | 1975 | tcp_clear_retrans(tp); |
463c84b9 | 1976 | inet_csk_delack_init(sk); |
fe067e8a | 1977 | tcp_init_send_head(sk); |
b40b4f79 | 1978 | memset(&tp->rx_opt, 0, sizeof(tp->rx_opt)); |
1da177e4 LT |
1979 | __sk_dst_reset(sk); |
1980 | ||
547b792c | 1981 | WARN_ON(inet->num && !icsk->icsk_bind_hash); |
1da177e4 LT |
1982 | |
1983 | sk->sk_error_report(sk); | |
1984 | return err; | |
1985 | } | |
1986 | ||
1da177e4 LT |
1987 | /* |
1988 | * Socket option code for TCP. | |
1989 | */ | |
3fdadf7d DM |
1990 | static int do_tcp_setsockopt(struct sock *sk, int level, |
1991 | int optname, char __user *optval, int optlen) | |
1da177e4 LT |
1992 | { |
1993 | struct tcp_sock *tp = tcp_sk(sk); | |
463c84b9 | 1994 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
1995 | int val; |
1996 | int err = 0; | |
1997 | ||
5f8ef48d SH |
1998 | /* This is a string value all the others are int's */ |
1999 | if (optname == TCP_CONGESTION) { | |
2000 | char name[TCP_CA_NAME_MAX]; | |
2001 | ||
2002 | if (optlen < 1) | |
2003 | return -EINVAL; | |
2004 | ||
2005 | val = strncpy_from_user(name, optval, | |
2006 | min(TCP_CA_NAME_MAX-1, optlen)); | |
2007 | if (val < 0) | |
2008 | return -EFAULT; | |
2009 | name[val] = 0; | |
2010 | ||
2011 | lock_sock(sk); | |
6687e988 | 2012 | err = tcp_set_congestion_control(sk, name); |
5f8ef48d SH |
2013 | release_sock(sk); |
2014 | return err; | |
2015 | } | |
2016 | ||
1da177e4 LT |
2017 | if (optlen < sizeof(int)) |
2018 | return -EINVAL; | |
2019 | ||
2020 | if (get_user(val, (int __user *)optval)) | |
2021 | return -EFAULT; | |
2022 | ||
2023 | lock_sock(sk); | |
2024 | ||
2025 | switch (optname) { | |
2026 | case TCP_MAXSEG: | |
2027 | /* Values greater than interface MTU won't take effect. However | |
2028 | * at the point when this call is done we typically don't yet | |
2029 | * know which interface is going to be used */ | |
2030 | if (val < 8 || val > MAX_TCP_WINDOW) { | |
2031 | err = -EINVAL; | |
2032 | break; | |
2033 | } | |
2034 | tp->rx_opt.user_mss = val; | |
2035 | break; | |
2036 | ||
2037 | case TCP_NODELAY: | |
2038 | if (val) { | |
2039 | /* TCP_NODELAY is weaker than TCP_CORK, so that | |
2040 | * this option on corked socket is remembered, but | |
2041 | * it is not activated until cork is cleared. | |
2042 | * | |
2043 | * However, when TCP_NODELAY is set we make | |
2044 | * an explicit push, which overrides even TCP_CORK | |
2045 | * for currently queued segments. | |
2046 | */ | |
2047 | tp->nonagle |= TCP_NAGLE_OFF|TCP_NAGLE_PUSH; | |
9e412ba7 | 2048 | tcp_push_pending_frames(sk); |
1da177e4 LT |
2049 | } else { |
2050 | tp->nonagle &= ~TCP_NAGLE_OFF; | |
2051 | } | |
2052 | break; | |
2053 | ||
2054 | case TCP_CORK: | |
2055 | /* When set indicates to always queue non-full frames. | |
2056 | * Later the user clears this option and we transmit | |
2057 | * any pending partial frames in the queue. This is | |
2058 | * meant to be used alongside sendfile() to get properly | |
2059 | * filled frames when the user (for example) must write | |
2060 | * out headers with a write() call first and then use | |
2061 | * sendfile to send out the data parts. | |
2062 | * | |
2063 | * TCP_CORK can be set together with TCP_NODELAY and it is | |
2064 | * stronger than TCP_NODELAY. | |
2065 | */ | |
2066 | if (val) { | |
2067 | tp->nonagle |= TCP_NAGLE_CORK; | |
2068 | } else { | |
2069 | tp->nonagle &= ~TCP_NAGLE_CORK; | |
2070 | if (tp->nonagle&TCP_NAGLE_OFF) | |
2071 | tp->nonagle |= TCP_NAGLE_PUSH; | |
9e412ba7 | 2072 | tcp_push_pending_frames(sk); |
1da177e4 LT |
2073 | } |
2074 | break; | |
2075 | ||
2076 | case TCP_KEEPIDLE: | |
2077 | if (val < 1 || val > MAX_TCP_KEEPIDLE) | |
2078 | err = -EINVAL; | |
2079 | else { | |
2080 | tp->keepalive_time = val * HZ; | |
2081 | if (sock_flag(sk, SOCK_KEEPOPEN) && | |
2082 | !((1 << sk->sk_state) & | |
2083 | (TCPF_CLOSE | TCPF_LISTEN))) { | |
2084 | __u32 elapsed = tcp_time_stamp - tp->rcv_tstamp; | |
2085 | if (tp->keepalive_time > elapsed) | |
2086 | elapsed = tp->keepalive_time - elapsed; | |
2087 | else | |
2088 | elapsed = 0; | |
463c84b9 | 2089 | inet_csk_reset_keepalive_timer(sk, elapsed); |
1da177e4 LT |
2090 | } |
2091 | } | |
2092 | break; | |
2093 | case TCP_KEEPINTVL: | |
2094 | if (val < 1 || val > MAX_TCP_KEEPINTVL) | |
2095 | err = -EINVAL; | |
2096 | else | |
2097 | tp->keepalive_intvl = val * HZ; | |
2098 | break; | |
2099 | case TCP_KEEPCNT: | |
2100 | if (val < 1 || val > MAX_TCP_KEEPCNT) | |
2101 | err = -EINVAL; | |
2102 | else | |
2103 | tp->keepalive_probes = val; | |
2104 | break; | |
2105 | case TCP_SYNCNT: | |
2106 | if (val < 1 || val > MAX_TCP_SYNCNT) | |
2107 | err = -EINVAL; | |
2108 | else | |
463c84b9 | 2109 | icsk->icsk_syn_retries = val; |
1da177e4 LT |
2110 | break; |
2111 | ||
2112 | case TCP_LINGER2: | |
2113 | if (val < 0) | |
2114 | tp->linger2 = -1; | |
2115 | else if (val > sysctl_tcp_fin_timeout / HZ) | |
2116 | tp->linger2 = 0; | |
2117 | else | |
2118 | tp->linger2 = val * HZ; | |
2119 | break; | |
2120 | ||
2121 | case TCP_DEFER_ACCEPT: | |
ec0a1966 DM |
2122 | icsk->icsk_accept_queue.rskq_defer_accept = 0; |
2123 | if (val > 0) { | |
2124 | /* Translate value in seconds to number of | |
2125 | * retransmits */ | |
2126 | while (icsk->icsk_accept_queue.rskq_defer_accept < 32 && | |
2127 | val > ((TCP_TIMEOUT_INIT / HZ) << | |
2128 | icsk->icsk_accept_queue.rskq_defer_accept)) | |
2129 | icsk->icsk_accept_queue.rskq_defer_accept++; | |
2130 | icsk->icsk_accept_queue.rskq_defer_accept++; | |
1da177e4 LT |
2131 | } |
2132 | break; | |
2133 | ||
2134 | case TCP_WINDOW_CLAMP: | |
2135 | if (!val) { | |
2136 | if (sk->sk_state != TCP_CLOSE) { | |
2137 | err = -EINVAL; | |
2138 | break; | |
2139 | } | |
2140 | tp->window_clamp = 0; | |
2141 | } else | |
2142 | tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ? | |
2143 | SOCK_MIN_RCVBUF / 2 : val; | |
2144 | break; | |
2145 | ||
2146 | case TCP_QUICKACK: | |
2147 | if (!val) { | |
463c84b9 | 2148 | icsk->icsk_ack.pingpong = 1; |
1da177e4 | 2149 | } else { |
463c84b9 | 2150 | icsk->icsk_ack.pingpong = 0; |
1da177e4 LT |
2151 | if ((1 << sk->sk_state) & |
2152 | (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) && | |
463c84b9 ACM |
2153 | inet_csk_ack_scheduled(sk)) { |
2154 | icsk->icsk_ack.pending |= ICSK_ACK_PUSHED; | |
0e4b4992 | 2155 | tcp_cleanup_rbuf(sk, 1); |
1da177e4 | 2156 | if (!(val & 1)) |
463c84b9 | 2157 | icsk->icsk_ack.pingpong = 1; |
1da177e4 LT |
2158 | } |
2159 | } | |
2160 | break; | |
2161 | ||
cfb6eeb4 YH |
2162 | #ifdef CONFIG_TCP_MD5SIG |
2163 | case TCP_MD5SIG: | |
2164 | /* Read the IP->Key mappings from userspace */ | |
2165 | err = tp->af_specific->md5_parse(sk, optval, optlen); | |
2166 | break; | |
2167 | #endif | |
2168 | ||
1da177e4 LT |
2169 | default: |
2170 | err = -ENOPROTOOPT; | |
2171 | break; | |
3ff50b79 SH |
2172 | } |
2173 | ||
1da177e4 LT |
2174 | release_sock(sk); |
2175 | return err; | |
2176 | } | |
2177 | ||
3fdadf7d DM |
2178 | int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval, |
2179 | int optlen) | |
2180 | { | |
2181 | struct inet_connection_sock *icsk = inet_csk(sk); | |
2182 | ||
2183 | if (level != SOL_TCP) | |
2184 | return icsk->icsk_af_ops->setsockopt(sk, level, optname, | |
2185 | optval, optlen); | |
2186 | return do_tcp_setsockopt(sk, level, optname, optval, optlen); | |
2187 | } | |
2188 | ||
2189 | #ifdef CONFIG_COMPAT | |
543d9cfe ACM |
2190 | int compat_tcp_setsockopt(struct sock *sk, int level, int optname, |
2191 | char __user *optval, int optlen) | |
3fdadf7d | 2192 | { |
dec73ff0 ACM |
2193 | if (level != SOL_TCP) |
2194 | return inet_csk_compat_setsockopt(sk, level, optname, | |
2195 | optval, optlen); | |
3fdadf7d DM |
2196 | return do_tcp_setsockopt(sk, level, optname, optval, optlen); |
2197 | } | |
543d9cfe ACM |
2198 | |
2199 | EXPORT_SYMBOL(compat_tcp_setsockopt); | |
3fdadf7d DM |
2200 | #endif |
2201 | ||
1da177e4 LT |
2202 | /* Return information about state of tcp endpoint in API format. */ |
2203 | void tcp_get_info(struct sock *sk, struct tcp_info *info) | |
2204 | { | |
2205 | struct tcp_sock *tp = tcp_sk(sk); | |
463c84b9 | 2206 | const struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
2207 | u32 now = tcp_time_stamp; |
2208 | ||
2209 | memset(info, 0, sizeof(*info)); | |
2210 | ||
2211 | info->tcpi_state = sk->sk_state; | |
6687e988 | 2212 | info->tcpi_ca_state = icsk->icsk_ca_state; |
463c84b9 | 2213 | info->tcpi_retransmits = icsk->icsk_retransmits; |
6687e988 | 2214 | info->tcpi_probes = icsk->icsk_probes_out; |
463c84b9 | 2215 | info->tcpi_backoff = icsk->icsk_backoff; |
1da177e4 LT |
2216 | |
2217 | if (tp->rx_opt.tstamp_ok) | |
2218 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; | |
e60402d0 | 2219 | if (tcp_is_sack(tp)) |
1da177e4 LT |
2220 | info->tcpi_options |= TCPI_OPT_SACK; |
2221 | if (tp->rx_opt.wscale_ok) { | |
2222 | info->tcpi_options |= TCPI_OPT_WSCALE; | |
2223 | info->tcpi_snd_wscale = tp->rx_opt.snd_wscale; | |
2224 | info->tcpi_rcv_wscale = tp->rx_opt.rcv_wscale; | |
e905a9ed | 2225 | } |
1da177e4 LT |
2226 | |
2227 | if (tp->ecn_flags&TCP_ECN_OK) | |
2228 | info->tcpi_options |= TCPI_OPT_ECN; | |
2229 | ||
463c84b9 ACM |
2230 | info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto); |
2231 | info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato); | |
c1b4a7e6 | 2232 | info->tcpi_snd_mss = tp->mss_cache; |
463c84b9 | 2233 | info->tcpi_rcv_mss = icsk->icsk_ack.rcv_mss; |
1da177e4 | 2234 | |
5ee3afba RJ |
2235 | if (sk->sk_state == TCP_LISTEN) { |
2236 | info->tcpi_unacked = sk->sk_ack_backlog; | |
2237 | info->tcpi_sacked = sk->sk_max_ack_backlog; | |
2238 | } else { | |
2239 | info->tcpi_unacked = tp->packets_out; | |
2240 | info->tcpi_sacked = tp->sacked_out; | |
2241 | } | |
1da177e4 LT |
2242 | info->tcpi_lost = tp->lost_out; |
2243 | info->tcpi_retrans = tp->retrans_out; | |
2244 | info->tcpi_fackets = tp->fackets_out; | |
2245 | ||
2246 | info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime); | |
463c84b9 | 2247 | info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime); |
1da177e4 LT |
2248 | info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp); |
2249 | ||
d83d8461 | 2250 | info->tcpi_pmtu = icsk->icsk_pmtu_cookie; |
1da177e4 LT |
2251 | info->tcpi_rcv_ssthresh = tp->rcv_ssthresh; |
2252 | info->tcpi_rtt = jiffies_to_usecs(tp->srtt)>>3; | |
2253 | info->tcpi_rttvar = jiffies_to_usecs(tp->mdev)>>2; | |
2254 | info->tcpi_snd_ssthresh = tp->snd_ssthresh; | |
2255 | info->tcpi_snd_cwnd = tp->snd_cwnd; | |
2256 | info->tcpi_advmss = tp->advmss; | |
2257 | info->tcpi_reordering = tp->reordering; | |
2258 | ||
2259 | info->tcpi_rcv_rtt = jiffies_to_usecs(tp->rcv_rtt_est.rtt)>>3; | |
2260 | info->tcpi_rcv_space = tp->rcvq_space.space; | |
2261 | ||
2262 | info->tcpi_total_retrans = tp->total_retrans; | |
2263 | } | |
2264 | ||
2265 | EXPORT_SYMBOL_GPL(tcp_get_info); | |
2266 | ||
3fdadf7d DM |
2267 | static int do_tcp_getsockopt(struct sock *sk, int level, |
2268 | int optname, char __user *optval, int __user *optlen) | |
1da177e4 | 2269 | { |
295f7324 | 2270 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
2271 | struct tcp_sock *tp = tcp_sk(sk); |
2272 | int val, len; | |
2273 | ||
1da177e4 LT |
2274 | if (get_user(len, optlen)) |
2275 | return -EFAULT; | |
2276 | ||
2277 | len = min_t(unsigned int, len, sizeof(int)); | |
2278 | ||
2279 | if (len < 0) | |
2280 | return -EINVAL; | |
2281 | ||
2282 | switch (optname) { | |
2283 | case TCP_MAXSEG: | |
c1b4a7e6 | 2284 | val = tp->mss_cache; |
1da177e4 LT |
2285 | if (!val && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) |
2286 | val = tp->rx_opt.user_mss; | |
2287 | break; | |
2288 | case TCP_NODELAY: | |
2289 | val = !!(tp->nonagle&TCP_NAGLE_OFF); | |
2290 | break; | |
2291 | case TCP_CORK: | |
2292 | val = !!(tp->nonagle&TCP_NAGLE_CORK); | |
2293 | break; | |
2294 | case TCP_KEEPIDLE: | |
2295 | val = (tp->keepalive_time ? : sysctl_tcp_keepalive_time) / HZ; | |
2296 | break; | |
2297 | case TCP_KEEPINTVL: | |
2298 | val = (tp->keepalive_intvl ? : sysctl_tcp_keepalive_intvl) / HZ; | |
2299 | break; | |
2300 | case TCP_KEEPCNT: | |
2301 | val = tp->keepalive_probes ? : sysctl_tcp_keepalive_probes; | |
2302 | break; | |
2303 | case TCP_SYNCNT: | |
295f7324 | 2304 | val = icsk->icsk_syn_retries ? : sysctl_tcp_syn_retries; |
1da177e4 LT |
2305 | break; |
2306 | case TCP_LINGER2: | |
2307 | val = tp->linger2; | |
2308 | if (val >= 0) | |
2309 | val = (val ? : sysctl_tcp_fin_timeout) / HZ; | |
2310 | break; | |
2311 | case TCP_DEFER_ACCEPT: | |
ec0a1966 DM |
2312 | val = !icsk->icsk_accept_queue.rskq_defer_accept ? 0 : |
2313 | ((TCP_TIMEOUT_INIT / HZ) << (icsk->icsk_accept_queue.rskq_defer_accept - 1)); | |
1da177e4 LT |
2314 | break; |
2315 | case TCP_WINDOW_CLAMP: | |
2316 | val = tp->window_clamp; | |
2317 | break; | |
2318 | case TCP_INFO: { | |
2319 | struct tcp_info info; | |
2320 | ||
2321 | if (get_user(len, optlen)) | |
2322 | return -EFAULT; | |
2323 | ||
2324 | tcp_get_info(sk, &info); | |
2325 | ||
2326 | len = min_t(unsigned int, len, sizeof(info)); | |
2327 | if (put_user(len, optlen)) | |
2328 | return -EFAULT; | |
2329 | if (copy_to_user(optval, &info, len)) | |
2330 | return -EFAULT; | |
2331 | return 0; | |
2332 | } | |
2333 | case TCP_QUICKACK: | |
295f7324 | 2334 | val = !icsk->icsk_ack.pingpong; |
1da177e4 | 2335 | break; |
5f8ef48d SH |
2336 | |
2337 | case TCP_CONGESTION: | |
2338 | if (get_user(len, optlen)) | |
2339 | return -EFAULT; | |
2340 | len = min_t(unsigned int, len, TCP_CA_NAME_MAX); | |
2341 | if (put_user(len, optlen)) | |
2342 | return -EFAULT; | |
6687e988 | 2343 | if (copy_to_user(optval, icsk->icsk_ca_ops->name, len)) |
5f8ef48d SH |
2344 | return -EFAULT; |
2345 | return 0; | |
1da177e4 LT |
2346 | default: |
2347 | return -ENOPROTOOPT; | |
3ff50b79 | 2348 | } |
1da177e4 LT |
2349 | |
2350 | if (put_user(len, optlen)) | |
2351 | return -EFAULT; | |
2352 | if (copy_to_user(optval, &val, len)) | |
2353 | return -EFAULT; | |
2354 | return 0; | |
2355 | } | |
2356 | ||
3fdadf7d DM |
2357 | int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, |
2358 | int __user *optlen) | |
2359 | { | |
2360 | struct inet_connection_sock *icsk = inet_csk(sk); | |
2361 | ||
2362 | if (level != SOL_TCP) | |
2363 | return icsk->icsk_af_ops->getsockopt(sk, level, optname, | |
2364 | optval, optlen); | |
2365 | return do_tcp_getsockopt(sk, level, optname, optval, optlen); | |
2366 | } | |
2367 | ||
2368 | #ifdef CONFIG_COMPAT | |
543d9cfe ACM |
2369 | int compat_tcp_getsockopt(struct sock *sk, int level, int optname, |
2370 | char __user *optval, int __user *optlen) | |
3fdadf7d | 2371 | { |
dec73ff0 ACM |
2372 | if (level != SOL_TCP) |
2373 | return inet_csk_compat_getsockopt(sk, level, optname, | |
2374 | optval, optlen); | |
3fdadf7d DM |
2375 | return do_tcp_getsockopt(sk, level, optname, optval, optlen); |
2376 | } | |
543d9cfe ACM |
2377 | |
2378 | EXPORT_SYMBOL(compat_tcp_getsockopt); | |
3fdadf7d | 2379 | #endif |
1da177e4 | 2380 | |
576a30eb | 2381 | struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int features) |
f4c50d99 HX |
2382 | { |
2383 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
2384 | struct tcphdr *th; | |
2385 | unsigned thlen; | |
2386 | unsigned int seq; | |
d3bc23e7 | 2387 | __be32 delta; |
f4c50d99 HX |
2388 | unsigned int oldlen; |
2389 | unsigned int len; | |
2390 | ||
2391 | if (!pskb_may_pull(skb, sizeof(*th))) | |
2392 | goto out; | |
2393 | ||
aa8223c7 | 2394 | th = tcp_hdr(skb); |
f4c50d99 HX |
2395 | thlen = th->doff * 4; |
2396 | if (thlen < sizeof(*th)) | |
2397 | goto out; | |
2398 | ||
2399 | if (!pskb_may_pull(skb, thlen)) | |
2400 | goto out; | |
2401 | ||
0718bcc0 | 2402 | oldlen = (u16)~skb->len; |
f4c50d99 HX |
2403 | __skb_pull(skb, thlen); |
2404 | ||
3820c3f3 HX |
2405 | if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) { |
2406 | /* Packet is from an untrusted source, reset gso_segs. */ | |
bbcf467d HX |
2407 | int type = skb_shinfo(skb)->gso_type; |
2408 | int mss; | |
2409 | ||
2410 | if (unlikely(type & | |
2411 | ~(SKB_GSO_TCPV4 | | |
2412 | SKB_GSO_DODGY | | |
2413 | SKB_GSO_TCP_ECN | | |
2414 | SKB_GSO_TCPV6 | | |
2415 | 0) || | |
2416 | !(type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))) | |
2417 | goto out; | |
3820c3f3 | 2418 | |
bbcf467d | 2419 | mss = skb_shinfo(skb)->gso_size; |
172589cc | 2420 | skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss); |
3820c3f3 HX |
2421 | |
2422 | segs = NULL; | |
2423 | goto out; | |
2424 | } | |
2425 | ||
576a30eb | 2426 | segs = skb_segment(skb, features); |
f4c50d99 HX |
2427 | if (IS_ERR(segs)) |
2428 | goto out; | |
2429 | ||
2430 | len = skb_shinfo(skb)->gso_size; | |
0718bcc0 | 2431 | delta = htonl(oldlen + (thlen + len)); |
f4c50d99 HX |
2432 | |
2433 | skb = segs; | |
aa8223c7 | 2434 | th = tcp_hdr(skb); |
f4c50d99 HX |
2435 | seq = ntohl(th->seq); |
2436 | ||
2437 | do { | |
2438 | th->fin = th->psh = 0; | |
2439 | ||
d3bc23e7 AV |
2440 | th->check = ~csum_fold((__force __wsum)((__force u32)th->check + |
2441 | (__force u32)delta)); | |
84fa7933 | 2442 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
9c70220b ACM |
2443 | th->check = |
2444 | csum_fold(csum_partial(skb_transport_header(skb), | |
2445 | thlen, skb->csum)); | |
f4c50d99 HX |
2446 | |
2447 | seq += len; | |
2448 | skb = skb->next; | |
aa8223c7 | 2449 | th = tcp_hdr(skb); |
f4c50d99 HX |
2450 | |
2451 | th->seq = htonl(seq); | |
2452 | th->cwr = 0; | |
2453 | } while (skb->next); | |
2454 | ||
27a884dc | 2455 | delta = htonl(oldlen + (skb->tail - skb->transport_header) + |
9c70220b | 2456 | skb->data_len); |
d3bc23e7 AV |
2457 | th->check = ~csum_fold((__force __wsum)((__force u32)th->check + |
2458 | (__force u32)delta)); | |
84fa7933 | 2459 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
9c70220b ACM |
2460 | th->check = csum_fold(csum_partial(skb_transport_header(skb), |
2461 | thlen, skb->csum)); | |
f4c50d99 HX |
2462 | |
2463 | out: | |
2464 | return segs; | |
2465 | } | |
adcfc7d0 | 2466 | EXPORT_SYMBOL(tcp_tso_segment); |
f4c50d99 | 2467 | |
bf296b12 HX |
2468 | struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb) |
2469 | { | |
2470 | struct sk_buff **pp = NULL; | |
2471 | struct sk_buff *p; | |
2472 | struct tcphdr *th; | |
2473 | struct tcphdr *th2; | |
2474 | unsigned int thlen; | |
2475 | unsigned int flags; | |
2476 | unsigned int total; | |
2477 | unsigned int mss = 1; | |
2478 | int flush = 1; | |
2479 | ||
2480 | if (!pskb_may_pull(skb, sizeof(*th))) | |
2481 | goto out; | |
2482 | ||
2483 | th = tcp_hdr(skb); | |
2484 | thlen = th->doff * 4; | |
2485 | if (thlen < sizeof(*th)) | |
2486 | goto out; | |
2487 | ||
2488 | if (!pskb_may_pull(skb, thlen)) | |
2489 | goto out; | |
2490 | ||
2491 | th = tcp_hdr(skb); | |
2492 | __skb_pull(skb, thlen); | |
2493 | ||
2494 | flags = tcp_flag_word(th); | |
2495 | ||
2496 | for (; (p = *head); head = &p->next) { | |
2497 | if (!NAPI_GRO_CB(p)->same_flow) | |
2498 | continue; | |
2499 | ||
2500 | th2 = tcp_hdr(p); | |
2501 | ||
2502 | if (th->source != th2->source || th->dest != th2->dest) { | |
2503 | NAPI_GRO_CB(p)->same_flow = 0; | |
2504 | continue; | |
2505 | } | |
2506 | ||
2507 | goto found; | |
2508 | } | |
2509 | ||
2510 | goto out_check_final; | |
2511 | ||
2512 | found: | |
2513 | flush = NAPI_GRO_CB(p)->flush; | |
2514 | flush |= flags & TCP_FLAG_CWR; | |
2515 | flush |= (flags ^ tcp_flag_word(th2)) & | |
2516 | ~(TCP_FLAG_CWR | TCP_FLAG_FIN | TCP_FLAG_PSH); | |
2517 | flush |= th->ack_seq != th2->ack_seq || th->window != th2->window; | |
2518 | flush |= memcmp(th + 1, th2 + 1, thlen - sizeof(*th)); | |
2519 | ||
2520 | total = p->len; | |
2521 | mss = total; | |
2522 | if (skb_shinfo(p)->frag_list) | |
2523 | mss = skb_shinfo(p)->frag_list->len; | |
2524 | ||
2525 | flush |= skb->len > mss || skb->len <= 0; | |
2526 | flush |= ntohl(th2->seq) + total != ntohl(th->seq); | |
2527 | ||
2528 | if (flush || skb_gro_receive(head, skb)) { | |
2529 | mss = 1; | |
2530 | goto out_check_final; | |
2531 | } | |
2532 | ||
2533 | p = *head; | |
2534 | th2 = tcp_hdr(p); | |
2535 | tcp_flag_word(th2) |= flags & (TCP_FLAG_FIN | TCP_FLAG_PSH); | |
2536 | ||
2537 | out_check_final: | |
2538 | flush = skb->len < mss; | |
2539 | flush |= flags & (TCP_FLAG_URG | TCP_FLAG_PSH | TCP_FLAG_RST | | |
2540 | TCP_FLAG_SYN | TCP_FLAG_FIN); | |
2541 | ||
2542 | if (p && (!NAPI_GRO_CB(skb)->same_flow || flush)) | |
2543 | pp = head; | |
2544 | ||
2545 | out: | |
2546 | NAPI_GRO_CB(skb)->flush |= flush; | |
2547 | ||
2548 | return pp; | |
2549 | } | |
2550 | ||
2551 | int tcp_gro_complete(struct sk_buff *skb) | |
2552 | { | |
2553 | struct tcphdr *th = tcp_hdr(skb); | |
2554 | ||
2555 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
2556 | skb->csum_offset = offsetof(struct tcphdr, check); | |
2557 | skb->ip_summed = CHECKSUM_PARTIAL; | |
2558 | ||
2559 | skb_shinfo(skb)->gso_size = skb_shinfo(skb)->frag_list->len; | |
2560 | skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; | |
2561 | ||
2562 | if (th->cwr) | |
2563 | skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; | |
2564 | ||
2565 | return 0; | |
2566 | } | |
2567 | ||
cfb6eeb4 YH |
2568 | #ifdef CONFIG_TCP_MD5SIG |
2569 | static unsigned long tcp_md5sig_users; | |
2570 | static struct tcp_md5sig_pool **tcp_md5sig_pool; | |
2571 | static DEFINE_SPINLOCK(tcp_md5sig_pool_lock); | |
2572 | ||
2573 | static void __tcp_free_md5sig_pool(struct tcp_md5sig_pool **pool) | |
2574 | { | |
2575 | int cpu; | |
2576 | for_each_possible_cpu(cpu) { | |
2577 | struct tcp_md5sig_pool *p = *per_cpu_ptr(pool, cpu); | |
2578 | if (p) { | |
2579 | if (p->md5_desc.tfm) | |
2580 | crypto_free_hash(p->md5_desc.tfm); | |
2581 | kfree(p); | |
2582 | p = NULL; | |
2583 | } | |
2584 | } | |
2585 | free_percpu(pool); | |
2586 | } | |
2587 | ||
2588 | void tcp_free_md5sig_pool(void) | |
2589 | { | |
2590 | struct tcp_md5sig_pool **pool = NULL; | |
2591 | ||
2c4f6219 | 2592 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2593 | if (--tcp_md5sig_users == 0) { |
2594 | pool = tcp_md5sig_pool; | |
2595 | tcp_md5sig_pool = NULL; | |
2596 | } | |
2c4f6219 | 2597 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2598 | if (pool) |
2599 | __tcp_free_md5sig_pool(pool); | |
2600 | } | |
2601 | ||
2602 | EXPORT_SYMBOL(tcp_free_md5sig_pool); | |
2603 | ||
f5b99bcd | 2604 | static struct tcp_md5sig_pool **__tcp_alloc_md5sig_pool(void) |
cfb6eeb4 YH |
2605 | { |
2606 | int cpu; | |
2607 | struct tcp_md5sig_pool **pool; | |
2608 | ||
2609 | pool = alloc_percpu(struct tcp_md5sig_pool *); | |
2610 | if (!pool) | |
2611 | return NULL; | |
2612 | ||
2613 | for_each_possible_cpu(cpu) { | |
2614 | struct tcp_md5sig_pool *p; | |
2615 | struct crypto_hash *hash; | |
2616 | ||
2617 | p = kzalloc(sizeof(*p), GFP_KERNEL); | |
2618 | if (!p) | |
2619 | goto out_free; | |
2620 | *per_cpu_ptr(pool, cpu) = p; | |
2621 | ||
2622 | hash = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC); | |
2623 | if (!hash || IS_ERR(hash)) | |
2624 | goto out_free; | |
2625 | ||
2626 | p->md5_desc.tfm = hash; | |
2627 | } | |
2628 | return pool; | |
2629 | out_free: | |
2630 | __tcp_free_md5sig_pool(pool); | |
2631 | return NULL; | |
2632 | } | |
2633 | ||
2634 | struct tcp_md5sig_pool **tcp_alloc_md5sig_pool(void) | |
2635 | { | |
2636 | struct tcp_md5sig_pool **pool; | |
2637 | int alloc = 0; | |
2638 | ||
2639 | retry: | |
2c4f6219 | 2640 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2641 | pool = tcp_md5sig_pool; |
2642 | if (tcp_md5sig_users++ == 0) { | |
2643 | alloc = 1; | |
2c4f6219 | 2644 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2645 | } else if (!pool) { |
2646 | tcp_md5sig_users--; | |
2c4f6219 | 2647 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2648 | cpu_relax(); |
2649 | goto retry; | |
2650 | } else | |
2c4f6219 | 2651 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2652 | |
2653 | if (alloc) { | |
2654 | /* we cannot hold spinlock here because this may sleep. */ | |
2655 | struct tcp_md5sig_pool **p = __tcp_alloc_md5sig_pool(); | |
2c4f6219 | 2656 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2657 | if (!p) { |
2658 | tcp_md5sig_users--; | |
2c4f6219 | 2659 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2660 | return NULL; |
2661 | } | |
2662 | pool = tcp_md5sig_pool; | |
2663 | if (pool) { | |
2664 | /* oops, it has already been assigned. */ | |
2c4f6219 | 2665 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2666 | __tcp_free_md5sig_pool(p); |
2667 | } else { | |
2668 | tcp_md5sig_pool = pool = p; | |
2c4f6219 | 2669 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2670 | } |
2671 | } | |
2672 | return pool; | |
2673 | } | |
2674 | ||
2675 | EXPORT_SYMBOL(tcp_alloc_md5sig_pool); | |
2676 | ||
2677 | struct tcp_md5sig_pool *__tcp_get_md5sig_pool(int cpu) | |
2678 | { | |
2679 | struct tcp_md5sig_pool **p; | |
2c4f6219 | 2680 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2681 | p = tcp_md5sig_pool; |
2682 | if (p) | |
2683 | tcp_md5sig_users++; | |
2c4f6219 | 2684 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2685 | return (p ? *per_cpu_ptr(p, cpu) : NULL); |
2686 | } | |
2687 | ||
2688 | EXPORT_SYMBOL(__tcp_get_md5sig_pool); | |
2689 | ||
6931ba7c DM |
2690 | void __tcp_put_md5sig_pool(void) |
2691 | { | |
2692 | tcp_free_md5sig_pool(); | |
cfb6eeb4 YH |
2693 | } |
2694 | ||
2695 | EXPORT_SYMBOL(__tcp_put_md5sig_pool); | |
49a72dfb AL |
2696 | |
2697 | int tcp_md5_hash_header(struct tcp_md5sig_pool *hp, | |
2698 | struct tcphdr *th) | |
2699 | { | |
2700 | struct scatterlist sg; | |
2701 | int err; | |
2702 | ||
2703 | __sum16 old_checksum = th->check; | |
2704 | th->check = 0; | |
2705 | /* options aren't included in the hash */ | |
2706 | sg_init_one(&sg, th, sizeof(struct tcphdr)); | |
2707 | err = crypto_hash_update(&hp->md5_desc, &sg, sizeof(struct tcphdr)); | |
2708 | th->check = old_checksum; | |
2709 | return err; | |
2710 | } | |
2711 | ||
2712 | EXPORT_SYMBOL(tcp_md5_hash_header); | |
2713 | ||
2714 | int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp, | |
2715 | struct sk_buff *skb, unsigned header_len) | |
2716 | { | |
2717 | struct scatterlist sg; | |
2718 | const struct tcphdr *tp = tcp_hdr(skb); | |
2719 | struct hash_desc *desc = &hp->md5_desc; | |
2720 | unsigned i; | |
2721 | const unsigned head_data_len = skb_headlen(skb) > header_len ? | |
2722 | skb_headlen(skb) - header_len : 0; | |
2723 | const struct skb_shared_info *shi = skb_shinfo(skb); | |
2724 | ||
2725 | sg_init_table(&sg, 1); | |
2726 | ||
2727 | sg_set_buf(&sg, ((u8 *) tp) + header_len, head_data_len); | |
2728 | if (crypto_hash_update(desc, &sg, head_data_len)) | |
2729 | return 1; | |
2730 | ||
2731 | for (i = 0; i < shi->nr_frags; ++i) { | |
2732 | const struct skb_frag_struct *f = &shi->frags[i]; | |
2733 | sg_set_page(&sg, f->page, f->size, f->page_offset); | |
2734 | if (crypto_hash_update(desc, &sg, f->size)) | |
2735 | return 1; | |
2736 | } | |
2737 | ||
2738 | return 0; | |
2739 | } | |
2740 | ||
2741 | EXPORT_SYMBOL(tcp_md5_hash_skb_data); | |
2742 | ||
2743 | int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, struct tcp_md5sig_key *key) | |
2744 | { | |
2745 | struct scatterlist sg; | |
2746 | ||
2747 | sg_init_one(&sg, key->key, key->keylen); | |
2748 | return crypto_hash_update(&hp->md5_desc, &sg, key->keylen); | |
2749 | } | |
2750 | ||
2751 | EXPORT_SYMBOL(tcp_md5_hash_key); | |
2752 | ||
cfb6eeb4 YH |
2753 | #endif |
2754 | ||
4ac02bab AK |
2755 | void tcp_done(struct sock *sk) |
2756 | { | |
5a5f3a8d | 2757 | if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV) |
63231bdd | 2758 | TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_ATTEMPTFAILS); |
4ac02bab AK |
2759 | |
2760 | tcp_set_state(sk, TCP_CLOSE); | |
2761 | tcp_clear_xmit_timers(sk); | |
2762 | ||
2763 | sk->sk_shutdown = SHUTDOWN_MASK; | |
2764 | ||
2765 | if (!sock_flag(sk, SOCK_DEAD)) | |
2766 | sk->sk_state_change(sk); | |
2767 | else | |
2768 | inet_csk_destroy_sock(sk); | |
2769 | } | |
2770 | EXPORT_SYMBOL_GPL(tcp_done); | |
2771 | ||
5f8ef48d | 2772 | extern struct tcp_congestion_ops tcp_reno; |
1da177e4 LT |
2773 | |
2774 | static __initdata unsigned long thash_entries; | |
2775 | static int __init set_thash_entries(char *str) | |
2776 | { | |
2777 | if (!str) | |
2778 | return 0; | |
2779 | thash_entries = simple_strtoul(str, &str, 0); | |
2780 | return 1; | |
2781 | } | |
2782 | __setup("thash_entries=", set_thash_entries); | |
2783 | ||
2784 | void __init tcp_init(void) | |
2785 | { | |
2786 | struct sk_buff *skb = NULL; | |
57413ebc | 2787 | unsigned long nr_pages, limit; |
7b4f4b5e | 2788 | int order, i, max_share; |
1da177e4 | 2789 | |
1f9e636e | 2790 | BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof(skb->cb)); |
1da177e4 | 2791 | |
1748376b | 2792 | percpu_counter_init(&tcp_sockets_allocated, 0); |
dd24c001 | 2793 | percpu_counter_init(&tcp_orphan_count, 0); |
6e04e021 ACM |
2794 | tcp_hashinfo.bind_bucket_cachep = |
2795 | kmem_cache_create("tcp_bind_bucket", | |
2796 | sizeof(struct inet_bind_bucket), 0, | |
20c2df83 | 2797 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 2798 | |
1da177e4 LT |
2799 | /* Size and allocate the main established and bind bucket |
2800 | * hash tables. | |
2801 | * | |
2802 | * The methodology is similar to that of the buffer cache. | |
2803 | */ | |
6e04e021 | 2804 | tcp_hashinfo.ehash = |
1da177e4 | 2805 | alloc_large_system_hash("TCP established", |
0f7ff927 | 2806 | sizeof(struct inet_ehash_bucket), |
1da177e4 LT |
2807 | thash_entries, |
2808 | (num_physpages >= 128 * 1024) ? | |
18955cfc | 2809 | 13 : 15, |
9e950efa | 2810 | 0, |
6e04e021 | 2811 | &tcp_hashinfo.ehash_size, |
1da177e4 | 2812 | NULL, |
0ccfe618 | 2813 | thash_entries ? 0 : 512 * 1024); |
dbca9b27 ED |
2814 | tcp_hashinfo.ehash_size = 1 << tcp_hashinfo.ehash_size; |
2815 | for (i = 0; i < tcp_hashinfo.ehash_size; i++) { | |
3ab5aee7 ED |
2816 | INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].chain, i); |
2817 | INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].twchain, i); | |
1da177e4 | 2818 | } |
230140cf ED |
2819 | if (inet_ehash_locks_alloc(&tcp_hashinfo)) |
2820 | panic("TCP: failed to alloc ehash_locks"); | |
6e04e021 | 2821 | tcp_hashinfo.bhash = |
1da177e4 | 2822 | alloc_large_system_hash("TCP bind", |
0f7ff927 | 2823 | sizeof(struct inet_bind_hashbucket), |
6e04e021 | 2824 | tcp_hashinfo.ehash_size, |
1da177e4 | 2825 | (num_physpages >= 128 * 1024) ? |
18955cfc | 2826 | 13 : 15, |
9e950efa | 2827 | 0, |
6e04e021 | 2828 | &tcp_hashinfo.bhash_size, |
1da177e4 LT |
2829 | NULL, |
2830 | 64 * 1024); | |
6e04e021 ACM |
2831 | tcp_hashinfo.bhash_size = 1 << tcp_hashinfo.bhash_size; |
2832 | for (i = 0; i < tcp_hashinfo.bhash_size; i++) { | |
2833 | spin_lock_init(&tcp_hashinfo.bhash[i].lock); | |
2834 | INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain); | |
1da177e4 LT |
2835 | } |
2836 | ||
2837 | /* Try to be a bit smarter and adjust defaults depending | |
2838 | * on available memory. | |
2839 | */ | |
2840 | for (order = 0; ((1 << order) << PAGE_SHIFT) < | |
6e04e021 | 2841 | (tcp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket)); |
1da177e4 LT |
2842 | order++) |
2843 | ; | |
e7626486 | 2844 | if (order >= 4) { |
295ff7ed | 2845 | tcp_death_row.sysctl_max_tw_buckets = 180000; |
1da177e4 LT |
2846 | sysctl_tcp_max_orphans = 4096 << (order - 4); |
2847 | sysctl_max_syn_backlog = 1024; | |
2848 | } else if (order < 3) { | |
295ff7ed | 2849 | tcp_death_row.sysctl_max_tw_buckets >>= (3 - order); |
1da177e4 LT |
2850 | sysctl_tcp_max_orphans >>= (3 - order); |
2851 | sysctl_max_syn_backlog = 128; | |
2852 | } | |
1da177e4 | 2853 | |
53cdcc04 JH |
2854 | /* Set the pressure threshold to be a fraction of global memory that |
2855 | * is up to 1/2 at 256 MB, decreasing toward zero with the amount of | |
2856 | * memory, with a floor of 128 pages. | |
2857 | */ | |
57413ebc MS |
2858 | nr_pages = totalram_pages - totalhigh_pages; |
2859 | limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT); | |
2860 | limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11); | |
53cdcc04 JH |
2861 | limit = max(limit, 128UL); |
2862 | sysctl_tcp_mem[0] = limit / 4 * 3; | |
2863 | sysctl_tcp_mem[1] = limit; | |
52bf376c | 2864 | sysctl_tcp_mem[2] = sysctl_tcp_mem[0] * 2; |
1da177e4 | 2865 | |
53cdcc04 | 2866 | /* Set per-socket limits to no more than 1/128 the pressure threshold */ |
7b4f4b5e JH |
2867 | limit = ((unsigned long)sysctl_tcp_mem[1]) << (PAGE_SHIFT - 7); |
2868 | max_share = min(4UL*1024*1024, limit); | |
2869 | ||
3ab224be | 2870 | sysctl_tcp_wmem[0] = SK_MEM_QUANTUM; |
7b4f4b5e JH |
2871 | sysctl_tcp_wmem[1] = 16*1024; |
2872 | sysctl_tcp_wmem[2] = max(64*1024, max_share); | |
2873 | ||
3ab224be | 2874 | sysctl_tcp_rmem[0] = SK_MEM_QUANTUM; |
7b4f4b5e JH |
2875 | sysctl_tcp_rmem[1] = 87380; |
2876 | sysctl_tcp_rmem[2] = max(87380, max_share); | |
1da177e4 LT |
2877 | |
2878 | printk(KERN_INFO "TCP: Hash tables configured " | |
2879 | "(established %d bind %d)\n", | |
dbca9b27 | 2880 | tcp_hashinfo.ehash_size, tcp_hashinfo.bhash_size); |
317a76f9 SH |
2881 | |
2882 | tcp_register_congestion_control(&tcp_reno); | |
1da177e4 LT |
2883 | } |
2884 | ||
1da177e4 | 2885 | EXPORT_SYMBOL(tcp_close); |
1da177e4 LT |
2886 | EXPORT_SYMBOL(tcp_disconnect); |
2887 | EXPORT_SYMBOL(tcp_getsockopt); | |
2888 | EXPORT_SYMBOL(tcp_ioctl); | |
1da177e4 LT |
2889 | EXPORT_SYMBOL(tcp_poll); |
2890 | EXPORT_SYMBOL(tcp_read_sock); | |
2891 | EXPORT_SYMBOL(tcp_recvmsg); | |
2892 | EXPORT_SYMBOL(tcp_sendmsg); | |
9c55e01c | 2893 | EXPORT_SYMBOL(tcp_splice_read); |
1da177e4 LT |
2894 | EXPORT_SYMBOL(tcp_sendpage); |
2895 | EXPORT_SYMBOL(tcp_setsockopt); | |
2896 | EXPORT_SYMBOL(tcp_shutdown); |