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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> |
da5c78c8 | 267 | #include <linux/time.h> |
1da177e4 LT |
268 | |
269 | #include <net/icmp.h> | |
270 | #include <net/tcp.h> | |
271 | #include <net/xfrm.h> | |
272 | #include <net/ip.h> | |
1a2449a8 | 273 | #include <net/netdma.h> |
9c55e01c | 274 | #include <net/sock.h> |
1da177e4 LT |
275 | |
276 | #include <asm/uaccess.h> | |
277 | #include <asm/ioctls.h> | |
278 | ||
ab32ea5d | 279 | int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT; |
1da177e4 | 280 | |
dd24c001 | 281 | struct percpu_counter tcp_orphan_count; |
0a5578cf ACM |
282 | EXPORT_SYMBOL_GPL(tcp_orphan_count); |
283 | ||
b8059ead DM |
284 | int sysctl_tcp_mem[3] __read_mostly; |
285 | int sysctl_tcp_wmem[3] __read_mostly; | |
286 | int sysctl_tcp_rmem[3] __read_mostly; | |
1da177e4 LT |
287 | |
288 | EXPORT_SYMBOL(sysctl_tcp_mem); | |
289 | EXPORT_SYMBOL(sysctl_tcp_rmem); | |
290 | EXPORT_SYMBOL(sysctl_tcp_wmem); | |
291 | ||
292 | atomic_t tcp_memory_allocated; /* Current allocated memory. */ | |
1da177e4 | 293 | EXPORT_SYMBOL(tcp_memory_allocated); |
1748376b ED |
294 | |
295 | /* | |
296 | * Current number of TCP sockets. | |
297 | */ | |
298 | struct percpu_counter tcp_sockets_allocated; | |
1da177e4 LT |
299 | EXPORT_SYMBOL(tcp_sockets_allocated); |
300 | ||
9c55e01c JA |
301 | /* |
302 | * TCP splice context | |
303 | */ | |
304 | struct tcp_splice_state { | |
305 | struct pipe_inode_info *pipe; | |
306 | size_t len; | |
307 | unsigned int flags; | |
308 | }; | |
309 | ||
1da177e4 LT |
310 | /* |
311 | * Pressure flag: try to collapse. | |
312 | * Technical note: it is used by multiple contexts non atomically. | |
3ab224be | 313 | * All the __sk_mem_schedule() is of this nature: accounting |
1da177e4 LT |
314 | * is strict, actions are advisory and have some latency. |
315 | */ | |
4103f8cd | 316 | int tcp_memory_pressure __read_mostly; |
1da177e4 LT |
317 | |
318 | EXPORT_SYMBOL(tcp_memory_pressure); | |
319 | ||
5c52ba17 | 320 | void tcp_enter_memory_pressure(struct sock *sk) |
1da177e4 LT |
321 | { |
322 | if (!tcp_memory_pressure) { | |
4e673444 | 323 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURES); |
1da177e4 LT |
324 | tcp_memory_pressure = 1; |
325 | } | |
326 | } | |
327 | ||
328 | EXPORT_SYMBOL(tcp_enter_memory_pressure); | |
329 | ||
b103cf34 JA |
330 | /* Convert seconds to retransmits based on initial and max timeout */ |
331 | static u8 secs_to_retrans(int seconds, int timeout, int rto_max) | |
332 | { | |
333 | u8 res = 0; | |
334 | ||
335 | if (seconds > 0) { | |
336 | int period = timeout; | |
337 | ||
338 | res = 1; | |
339 | while (seconds > period && res < 255) { | |
340 | res++; | |
341 | timeout <<= 1; | |
342 | if (timeout > rto_max) | |
343 | timeout = rto_max; | |
344 | period += timeout; | |
345 | } | |
346 | } | |
347 | return res; | |
348 | } | |
349 | ||
350 | /* Convert retransmits to seconds based on initial and max timeout */ | |
351 | static int retrans_to_secs(u8 retrans, int timeout, int rto_max) | |
352 | { | |
353 | int period = 0; | |
354 | ||
355 | if (retrans > 0) { | |
356 | period = timeout; | |
357 | while (--retrans) { | |
358 | timeout <<= 1; | |
359 | if (timeout > rto_max) | |
360 | timeout = rto_max; | |
361 | period += timeout; | |
362 | } | |
363 | } | |
364 | return period; | |
365 | } | |
366 | ||
1da177e4 LT |
367 | /* |
368 | * Wait for a TCP event. | |
369 | * | |
370 | * Note that we don't need to lock the socket, as the upper poll layers | |
371 | * take care of normal races (between the test and the event) and we don't | |
372 | * go look at any of the socket buffers directly. | |
373 | */ | |
374 | unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait) | |
375 | { | |
376 | unsigned int mask; | |
377 | struct sock *sk = sock->sk; | |
378 | struct tcp_sock *tp = tcp_sk(sk); | |
379 | ||
a57de0b4 | 380 | sock_poll_wait(file, sk->sk_sleep, wait); |
1da177e4 | 381 | if (sk->sk_state == TCP_LISTEN) |
dc40c7bc | 382 | return inet_csk_listen_poll(sk); |
1da177e4 LT |
383 | |
384 | /* Socket is not locked. We are protected from async events | |
70efce27 WN |
385 | * by poll logic and correct handling of state changes |
386 | * made by other threads is impossible in any case. | |
1da177e4 LT |
387 | */ |
388 | ||
389 | mask = 0; | |
390 | if (sk->sk_err) | |
391 | mask = POLLERR; | |
392 | ||
393 | /* | |
394 | * POLLHUP is certainly not done right. But poll() doesn't | |
395 | * have a notion of HUP in just one direction, and for a | |
396 | * socket the read side is more interesting. | |
397 | * | |
398 | * Some poll() documentation says that POLLHUP is incompatible | |
399 | * with the POLLOUT/POLLWR flags, so somebody should check this | |
400 | * all. But careful, it tends to be safer to return too many | |
401 | * bits than too few, and you can easily break real applications | |
402 | * if you don't tell them that something has hung up! | |
403 | * | |
404 | * Check-me. | |
405 | * | |
406 | * Check number 1. POLLHUP is _UNMASKABLE_ event (see UNIX98 and | |
407 | * our fs/select.c). It means that after we received EOF, | |
408 | * poll always returns immediately, making impossible poll() on write() | |
409 | * in state CLOSE_WAIT. One solution is evident --- to set POLLHUP | |
410 | * if and only if shutdown has been made in both directions. | |
411 | * Actually, it is interesting to look how Solaris and DUX | |
70efce27 | 412 | * solve this dilemma. I would prefer, if POLLHUP were maskable, |
1da177e4 LT |
413 | * then we could set it on SND_SHUTDOWN. BTW examples given |
414 | * in Stevens' books assume exactly this behaviour, it explains | |
70efce27 | 415 | * why POLLHUP is incompatible with POLLOUT. --ANK |
1da177e4 LT |
416 | * |
417 | * NOTE. Check for TCP_CLOSE is added. The goal is to prevent | |
418 | * blocking on fresh not-connected or disconnected socket. --ANK | |
419 | */ | |
420 | if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == TCP_CLOSE) | |
421 | mask |= POLLHUP; | |
422 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
f348d70a | 423 | mask |= POLLIN | POLLRDNORM | POLLRDHUP; |
1da177e4 LT |
424 | |
425 | /* Connected? */ | |
426 | if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV)) { | |
c7004482 DM |
427 | int target = sock_rcvlowat(sk, 0, INT_MAX); |
428 | ||
429 | if (tp->urg_seq == tp->copied_seq && | |
430 | !sock_flag(sk, SOCK_URGINLINE) && | |
431 | tp->urg_data) | |
432 | target--; | |
433 | ||
1da177e4 LT |
434 | /* Potential race condition. If read of tp below will |
435 | * escape above sk->sk_state, we can be illegally awaken | |
436 | * in SYN_* states. */ | |
c7004482 | 437 | if (tp->rcv_nxt - tp->copied_seq >= target) |
1da177e4 LT |
438 | mask |= POLLIN | POLLRDNORM; |
439 | ||
440 | if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { | |
441 | if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) { | |
442 | mask |= POLLOUT | POLLWRNORM; | |
443 | } else { /* send SIGIO later */ | |
444 | set_bit(SOCK_ASYNC_NOSPACE, | |
445 | &sk->sk_socket->flags); | |
446 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
447 | ||
448 | /* Race breaker. If space is freed after | |
449 | * wspace test but before the flags are set, | |
450 | * IO signal will be lost. | |
451 | */ | |
452 | if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) | |
453 | mask |= POLLOUT | POLLWRNORM; | |
454 | } | |
455 | } | |
456 | ||
457 | if (tp->urg_data & TCP_URG_VALID) | |
458 | mask |= POLLPRI; | |
459 | } | |
460 | return mask; | |
461 | } | |
462 | ||
463 | int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg) | |
464 | { | |
465 | struct tcp_sock *tp = tcp_sk(sk); | |
466 | int answ; | |
467 | ||
468 | switch (cmd) { | |
469 | case SIOCINQ: | |
470 | if (sk->sk_state == TCP_LISTEN) | |
471 | return -EINVAL; | |
472 | ||
473 | lock_sock(sk); | |
474 | if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) | |
475 | answ = 0; | |
476 | else if (sock_flag(sk, SOCK_URGINLINE) || | |
477 | !tp->urg_data || | |
478 | before(tp->urg_seq, tp->copied_seq) || | |
479 | !before(tp->urg_seq, tp->rcv_nxt)) { | |
91521944 DM |
480 | struct sk_buff *skb; |
481 | ||
1da177e4 LT |
482 | answ = tp->rcv_nxt - tp->copied_seq; |
483 | ||
484 | /* Subtract 1, if FIN is in queue. */ | |
91521944 DM |
485 | skb = skb_peek_tail(&sk->sk_receive_queue); |
486 | if (answ && skb) | |
487 | answ -= tcp_hdr(skb)->fin; | |
1da177e4 LT |
488 | } else |
489 | answ = tp->urg_seq - tp->copied_seq; | |
490 | release_sock(sk); | |
491 | break; | |
492 | case SIOCATMARK: | |
493 | answ = tp->urg_data && tp->urg_seq == tp->copied_seq; | |
494 | break; | |
495 | case SIOCOUTQ: | |
496 | if (sk->sk_state == TCP_LISTEN) | |
497 | return -EINVAL; | |
498 | ||
499 | if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) | |
500 | answ = 0; | |
501 | else | |
502 | answ = tp->write_seq - tp->snd_una; | |
503 | break; | |
504 | default: | |
505 | return -ENOIOCTLCMD; | |
3ff50b79 | 506 | } |
1da177e4 LT |
507 | |
508 | return put_user(answ, (int __user *)arg); | |
509 | } | |
510 | ||
1da177e4 LT |
511 | static inline void tcp_mark_push(struct tcp_sock *tp, struct sk_buff *skb) |
512 | { | |
513 | TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH; | |
514 | tp->pushed_seq = tp->write_seq; | |
515 | } | |
516 | ||
517 | static inline int forced_push(struct tcp_sock *tp) | |
518 | { | |
519 | return after(tp->write_seq, tp->pushed_seq + (tp->max_window >> 1)); | |
520 | } | |
521 | ||
9e412ba7 | 522 | static inline void skb_entail(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 523 | { |
9e412ba7 | 524 | struct tcp_sock *tp = tcp_sk(sk); |
352d4800 ACM |
525 | struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); |
526 | ||
527 | skb->csum = 0; | |
528 | tcb->seq = tcb->end_seq = tp->write_seq; | |
529 | tcb->flags = TCPCB_FLAG_ACK; | |
530 | tcb->sacked = 0; | |
1da177e4 | 531 | skb_header_release(skb); |
fe067e8a | 532 | tcp_add_write_queue_tail(sk, skb); |
3ab224be HA |
533 | sk->sk_wmem_queued += skb->truesize; |
534 | sk_mem_charge(sk, skb->truesize); | |
89ebd197 | 535 | if (tp->nonagle & TCP_NAGLE_PUSH) |
e905a9ed | 536 | tp->nonagle &= ~TCP_NAGLE_PUSH; |
1da177e4 LT |
537 | } |
538 | ||
afeca340 | 539 | static inline void tcp_mark_urg(struct tcp_sock *tp, int flags) |
1da177e4 | 540 | { |
33f5f57e | 541 | if (flags & MSG_OOB) |
1da177e4 | 542 | tp->snd_up = tp->write_seq; |
1da177e4 LT |
543 | } |
544 | ||
9e412ba7 IJ |
545 | static inline void tcp_push(struct sock *sk, int flags, int mss_now, |
546 | int nonagle) | |
1da177e4 | 547 | { |
fe067e8a | 548 | if (tcp_send_head(sk)) { |
afeca340 KK |
549 | struct tcp_sock *tp = tcp_sk(sk); |
550 | ||
1da177e4 | 551 | if (!(flags & MSG_MORE) || forced_push(tp)) |
afeca340 KK |
552 | tcp_mark_push(tp, tcp_write_queue_tail(sk)); |
553 | ||
554 | tcp_mark_urg(tp, flags); | |
9e412ba7 | 555 | __tcp_push_pending_frames(sk, mss_now, |
1da177e4 LT |
556 | (flags & MSG_MORE) ? TCP_NAGLE_CORK : nonagle); |
557 | } | |
558 | } | |
559 | ||
6ff7751d AB |
560 | static int tcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, |
561 | unsigned int offset, size_t len) | |
9c55e01c JA |
562 | { |
563 | struct tcp_splice_state *tss = rd_desc->arg.data; | |
33966dd0 | 564 | int ret; |
9c55e01c | 565 | |
9fa5fdf2 DM |
566 | ret = skb_splice_bits(skb, offset, tss->pipe, min(rd_desc->count, len), |
567 | tss->flags); | |
33966dd0 WT |
568 | if (ret > 0) |
569 | rd_desc->count -= ret; | |
570 | return ret; | |
9c55e01c JA |
571 | } |
572 | ||
573 | static int __tcp_splice_read(struct sock *sk, struct tcp_splice_state *tss) | |
574 | { | |
575 | /* Store TCP splice context information in read_descriptor_t. */ | |
576 | read_descriptor_t rd_desc = { | |
577 | .arg.data = tss, | |
33966dd0 | 578 | .count = tss->len, |
9c55e01c JA |
579 | }; |
580 | ||
581 | return tcp_read_sock(sk, &rd_desc, tcp_splice_data_recv); | |
582 | } | |
583 | ||
584 | /** | |
585 | * tcp_splice_read - splice data from TCP socket to a pipe | |
586 | * @sock: socket to splice from | |
587 | * @ppos: position (not valid) | |
588 | * @pipe: pipe to splice to | |
589 | * @len: number of bytes to splice | |
590 | * @flags: splice modifier flags | |
591 | * | |
592 | * Description: | |
593 | * Will read pages from given socket and fill them into a pipe. | |
594 | * | |
595 | **/ | |
596 | ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos, | |
597 | struct pipe_inode_info *pipe, size_t len, | |
598 | unsigned int flags) | |
599 | { | |
600 | struct sock *sk = sock->sk; | |
601 | struct tcp_splice_state tss = { | |
602 | .pipe = pipe, | |
603 | .len = len, | |
604 | .flags = flags, | |
605 | }; | |
606 | long timeo; | |
607 | ssize_t spliced; | |
608 | int ret; | |
609 | ||
610 | /* | |
611 | * We can't seek on a socket input | |
612 | */ | |
613 | if (unlikely(*ppos)) | |
614 | return -ESPIPE; | |
615 | ||
616 | ret = spliced = 0; | |
617 | ||
618 | lock_sock(sk); | |
619 | ||
42324c62 | 620 | timeo = sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK); |
9c55e01c JA |
621 | while (tss.len) { |
622 | ret = __tcp_splice_read(sk, &tss); | |
623 | if (ret < 0) | |
624 | break; | |
625 | else if (!ret) { | |
626 | if (spliced) | |
627 | break; | |
9c55e01c JA |
628 | if (sock_flag(sk, SOCK_DONE)) |
629 | break; | |
630 | if (sk->sk_err) { | |
631 | ret = sock_error(sk); | |
632 | break; | |
633 | } | |
634 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
635 | break; | |
636 | if (sk->sk_state == TCP_CLOSE) { | |
637 | /* | |
638 | * This occurs when user tries to read | |
639 | * from never connected socket. | |
640 | */ | |
641 | if (!sock_flag(sk, SOCK_DONE)) | |
642 | ret = -ENOTCONN; | |
643 | break; | |
644 | } | |
645 | if (!timeo) { | |
646 | ret = -EAGAIN; | |
647 | break; | |
648 | } | |
649 | sk_wait_data(sk, &timeo); | |
650 | if (signal_pending(current)) { | |
651 | ret = sock_intr_errno(timeo); | |
652 | break; | |
653 | } | |
654 | continue; | |
655 | } | |
656 | tss.len -= ret; | |
657 | spliced += ret; | |
658 | ||
33966dd0 WT |
659 | if (!timeo) |
660 | break; | |
9c55e01c JA |
661 | release_sock(sk); |
662 | lock_sock(sk); | |
663 | ||
664 | if (sk->sk_err || sk->sk_state == TCP_CLOSE || | |
33966dd0 | 665 | (sk->sk_shutdown & RCV_SHUTDOWN) || |
9c55e01c JA |
666 | signal_pending(current)) |
667 | break; | |
668 | } | |
669 | ||
670 | release_sock(sk); | |
671 | ||
672 | if (spliced) | |
673 | return spliced; | |
674 | ||
675 | return ret; | |
676 | } | |
677 | ||
df97c708 | 678 | struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp) |
f561d0f2 PE |
679 | { |
680 | struct sk_buff *skb; | |
681 | ||
682 | /* The TCP header must be at least 32-bit aligned. */ | |
683 | size = ALIGN(size, 4); | |
684 | ||
685 | skb = alloc_skb_fclone(size + sk->sk_prot->max_header, gfp); | |
686 | if (skb) { | |
3ab224be | 687 | if (sk_wmem_schedule(sk, skb->truesize)) { |
f561d0f2 PE |
688 | /* |
689 | * Make sure that we have exactly size bytes | |
690 | * available to the caller, no more, no less. | |
691 | */ | |
692 | skb_reserve(skb, skb_tailroom(skb) - size); | |
693 | return skb; | |
694 | } | |
695 | __kfree_skb(skb); | |
696 | } else { | |
5c52ba17 | 697 | sk->sk_prot->enter_memory_pressure(sk); |
f561d0f2 PE |
698 | sk_stream_moderate_sndbuf(sk); |
699 | } | |
700 | return NULL; | |
701 | } | |
702 | ||
0c54b85f IJ |
703 | static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now, |
704 | int large_allowed) | |
705 | { | |
706 | struct tcp_sock *tp = tcp_sk(sk); | |
2a3a041c | 707 | u32 xmit_size_goal, old_size_goal; |
0c54b85f IJ |
708 | |
709 | xmit_size_goal = mss_now; | |
710 | ||
711 | if (large_allowed && sk_can_gso(sk)) { | |
712 | xmit_size_goal = ((sk->sk_gso_max_size - 1) - | |
713 | inet_csk(sk)->icsk_af_ops->net_header_len - | |
714 | inet_csk(sk)->icsk_ext_hdr_len - | |
715 | tp->tcp_header_len); | |
716 | ||
717 | xmit_size_goal = tcp_bound_to_half_wnd(tp, xmit_size_goal); | |
2a3a041c IJ |
718 | |
719 | /* We try hard to avoid divides here */ | |
720 | old_size_goal = tp->xmit_size_goal_segs * mss_now; | |
721 | ||
722 | if (likely(old_size_goal <= xmit_size_goal && | |
723 | old_size_goal + mss_now > xmit_size_goal)) { | |
724 | xmit_size_goal = old_size_goal; | |
725 | } else { | |
726 | tp->xmit_size_goal_segs = xmit_size_goal / mss_now; | |
727 | xmit_size_goal = tp->xmit_size_goal_segs * mss_now; | |
728 | } | |
0c54b85f IJ |
729 | } |
730 | ||
afece1c6 | 731 | return max(xmit_size_goal, mss_now); |
0c54b85f IJ |
732 | } |
733 | ||
734 | static int tcp_send_mss(struct sock *sk, int *size_goal, int flags) | |
735 | { | |
736 | int mss_now; | |
737 | ||
738 | mss_now = tcp_current_mss(sk); | |
739 | *size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB)); | |
740 | ||
741 | return mss_now; | |
742 | } | |
743 | ||
1da177e4 LT |
744 | static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffset, |
745 | size_t psize, int flags) | |
746 | { | |
747 | struct tcp_sock *tp = tcp_sk(sk); | |
c1b4a7e6 | 748 | int mss_now, size_goal; |
1da177e4 LT |
749 | int err; |
750 | ssize_t copied; | |
751 | long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); | |
752 | ||
753 | /* Wait for a connection to finish. */ | |
754 | if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) | |
755 | if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) | |
756 | goto out_err; | |
757 | ||
758 | clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
759 | ||
0c54b85f | 760 | mss_now = tcp_send_mss(sk, &size_goal, flags); |
1da177e4 LT |
761 | copied = 0; |
762 | ||
763 | err = -EPIPE; | |
764 | if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) | |
0d6a775e | 765 | goto out_err; |
1da177e4 LT |
766 | |
767 | while (psize > 0) { | |
fe067e8a | 768 | struct sk_buff *skb = tcp_write_queue_tail(sk); |
1da177e4 LT |
769 | struct page *page = pages[poffset / PAGE_SIZE]; |
770 | int copy, i, can_coalesce; | |
771 | int offset = poffset % PAGE_SIZE; | |
772 | int size = min_t(size_t, psize, PAGE_SIZE - offset); | |
773 | ||
fe067e8a | 774 | if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0) { |
1da177e4 LT |
775 | new_segment: |
776 | if (!sk_stream_memory_free(sk)) | |
777 | goto wait_for_sndbuf; | |
778 | ||
df97c708 | 779 | skb = sk_stream_alloc_skb(sk, 0, sk->sk_allocation); |
1da177e4 LT |
780 | if (!skb) |
781 | goto wait_for_memory; | |
782 | ||
9e412ba7 | 783 | skb_entail(sk, skb); |
c1b4a7e6 | 784 | copy = size_goal; |
1da177e4 LT |
785 | } |
786 | ||
787 | if (copy > size) | |
788 | copy = size; | |
789 | ||
790 | i = skb_shinfo(skb)->nr_frags; | |
791 | can_coalesce = skb_can_coalesce(skb, i, page, offset); | |
792 | if (!can_coalesce && i >= MAX_SKB_FRAGS) { | |
793 | tcp_mark_push(tp, skb); | |
794 | goto new_segment; | |
795 | } | |
3ab224be | 796 | if (!sk_wmem_schedule(sk, copy)) |
1da177e4 | 797 | goto wait_for_memory; |
e905a9ed | 798 | |
1da177e4 LT |
799 | if (can_coalesce) { |
800 | skb_shinfo(skb)->frags[i - 1].size += copy; | |
801 | } else { | |
802 | get_page(page); | |
803 | skb_fill_page_desc(skb, i, page, offset, copy); | |
804 | } | |
805 | ||
806 | skb->len += copy; | |
807 | skb->data_len += copy; | |
808 | skb->truesize += copy; | |
809 | sk->sk_wmem_queued += copy; | |
3ab224be | 810 | sk_mem_charge(sk, copy); |
84fa7933 | 811 | skb->ip_summed = CHECKSUM_PARTIAL; |
1da177e4 LT |
812 | tp->write_seq += copy; |
813 | TCP_SKB_CB(skb)->end_seq += copy; | |
7967168c | 814 | skb_shinfo(skb)->gso_segs = 0; |
1da177e4 LT |
815 | |
816 | if (!copied) | |
817 | TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_PSH; | |
818 | ||
819 | copied += copy; | |
820 | poffset += copy; | |
821 | if (!(psize -= copy)) | |
822 | goto out; | |
823 | ||
69d15067 | 824 | if (skb->len < size_goal || (flags & MSG_OOB)) |
1da177e4 LT |
825 | continue; |
826 | ||
827 | if (forced_push(tp)) { | |
828 | tcp_mark_push(tp, skb); | |
9e412ba7 | 829 | __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH); |
fe067e8a | 830 | } else if (skb == tcp_send_head(sk)) |
1da177e4 LT |
831 | tcp_push_one(sk, mss_now); |
832 | continue; | |
833 | ||
834 | wait_for_sndbuf: | |
835 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
836 | wait_for_memory: | |
837 | if (copied) | |
9e412ba7 | 838 | tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH); |
1da177e4 LT |
839 | |
840 | if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) | |
841 | goto do_error; | |
842 | ||
0c54b85f | 843 | mss_now = tcp_send_mss(sk, &size_goal, flags); |
1da177e4 LT |
844 | } |
845 | ||
846 | out: | |
847 | if (copied) | |
9e412ba7 | 848 | tcp_push(sk, flags, mss_now, tp->nonagle); |
1da177e4 LT |
849 | return copied; |
850 | ||
851 | do_error: | |
852 | if (copied) | |
853 | goto out; | |
854 | out_err: | |
855 | return sk_stream_error(sk, flags, err); | |
856 | } | |
857 | ||
858 | ssize_t tcp_sendpage(struct socket *sock, struct page *page, int offset, | |
859 | size_t size, int flags) | |
860 | { | |
861 | ssize_t res; | |
862 | struct sock *sk = sock->sk; | |
863 | ||
1da177e4 | 864 | if (!(sk->sk_route_caps & NETIF_F_SG) || |
8648b305 | 865 | !(sk->sk_route_caps & NETIF_F_ALL_CSUM)) |
1da177e4 LT |
866 | return sock_no_sendpage(sock, page, offset, size, flags); |
867 | ||
1da177e4 LT |
868 | lock_sock(sk); |
869 | TCP_CHECK_TIMER(sk); | |
870 | res = do_tcp_sendpages(sk, &page, offset, size, flags); | |
871 | TCP_CHECK_TIMER(sk); | |
872 | release_sock(sk); | |
873 | return res; | |
874 | } | |
875 | ||
876 | #define TCP_PAGE(sk) (sk->sk_sndmsg_page) | |
877 | #define TCP_OFF(sk) (sk->sk_sndmsg_off) | |
878 | ||
def87cf4 | 879 | static inline int select_size(struct sock *sk, int sg) |
1da177e4 | 880 | { |
9e412ba7 | 881 | struct tcp_sock *tp = tcp_sk(sk); |
c1b4a7e6 | 882 | int tmp = tp->mss_cache; |
1da177e4 | 883 | |
def87cf4 | 884 | if (sg) { |
bcd76111 | 885 | if (sk_can_gso(sk)) |
b4e26f5e DM |
886 | tmp = 0; |
887 | else { | |
888 | int pgbreak = SKB_MAX_HEAD(MAX_TCP_HEADER); | |
889 | ||
890 | if (tmp >= pgbreak && | |
891 | tmp <= pgbreak + (MAX_SKB_FRAGS - 1) * PAGE_SIZE) | |
892 | tmp = pgbreak; | |
893 | } | |
894 | } | |
1da177e4 | 895 | |
1da177e4 LT |
896 | return tmp; |
897 | } | |
898 | ||
3516ffb0 | 899 | int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, |
1da177e4 LT |
900 | size_t size) |
901 | { | |
3516ffb0 | 902 | struct sock *sk = sock->sk; |
1da177e4 LT |
903 | struct iovec *iov; |
904 | struct tcp_sock *tp = tcp_sk(sk); | |
905 | struct sk_buff *skb; | |
906 | int iovlen, flags; | |
c1b4a7e6 | 907 | int mss_now, size_goal; |
def87cf4 | 908 | int sg, err, copied; |
1da177e4 LT |
909 | long timeo; |
910 | ||
911 | lock_sock(sk); | |
912 | TCP_CHECK_TIMER(sk); | |
913 | ||
914 | flags = msg->msg_flags; | |
915 | timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); | |
916 | ||
917 | /* Wait for a connection to finish. */ | |
918 | if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) | |
919 | if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) | |
920 | goto out_err; | |
921 | ||
922 | /* This should be in poll */ | |
923 | clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
924 | ||
0c54b85f | 925 | mss_now = tcp_send_mss(sk, &size_goal, flags); |
1da177e4 LT |
926 | |
927 | /* Ok commence sending. */ | |
928 | iovlen = msg->msg_iovlen; | |
929 | iov = msg->msg_iov; | |
930 | copied = 0; | |
931 | ||
932 | err = -EPIPE; | |
933 | if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) | |
0d6a775e | 934 | goto out_err; |
1da177e4 | 935 | |
def87cf4 KK |
936 | sg = sk->sk_route_caps & NETIF_F_SG; |
937 | ||
1da177e4 LT |
938 | while (--iovlen >= 0) { |
939 | int seglen = iov->iov_len; | |
940 | unsigned char __user *from = iov->iov_base; | |
941 | ||
942 | iov++; | |
943 | ||
944 | while (seglen > 0) { | |
6828b92b HX |
945 | int copy = 0; |
946 | int max = size_goal; | |
1da177e4 | 947 | |
fe067e8a | 948 | skb = tcp_write_queue_tail(sk); |
6828b92b HX |
949 | if (tcp_send_head(sk)) { |
950 | if (skb->ip_summed == CHECKSUM_NONE) | |
951 | max = mss_now; | |
952 | copy = max - skb->len; | |
953 | } | |
1da177e4 | 954 | |
6828b92b | 955 | if (copy <= 0) { |
1da177e4 LT |
956 | new_segment: |
957 | /* Allocate new segment. If the interface is SG, | |
958 | * allocate skb fitting to single page. | |
959 | */ | |
960 | if (!sk_stream_memory_free(sk)) | |
961 | goto wait_for_sndbuf; | |
962 | ||
def87cf4 KK |
963 | skb = sk_stream_alloc_skb(sk, |
964 | select_size(sk, sg), | |
965 | sk->sk_allocation); | |
1da177e4 LT |
966 | if (!skb) |
967 | goto wait_for_memory; | |
968 | ||
969 | /* | |
970 | * Check whether we can use HW checksum. | |
971 | */ | |
8648b305 | 972 | if (sk->sk_route_caps & NETIF_F_ALL_CSUM) |
84fa7933 | 973 | skb->ip_summed = CHECKSUM_PARTIAL; |
1da177e4 | 974 | |
9e412ba7 | 975 | skb_entail(sk, skb); |
c1b4a7e6 | 976 | copy = size_goal; |
6828b92b | 977 | max = size_goal; |
1da177e4 LT |
978 | } |
979 | ||
980 | /* Try to append data to the end of skb. */ | |
981 | if (copy > seglen) | |
982 | copy = seglen; | |
983 | ||
984 | /* Where to copy to? */ | |
985 | if (skb_tailroom(skb) > 0) { | |
986 | /* We have some space in skb head. Superb! */ | |
987 | if (copy > skb_tailroom(skb)) | |
988 | copy = skb_tailroom(skb); | |
989 | if ((err = skb_add_data(skb, from, copy)) != 0) | |
990 | goto do_fault; | |
991 | } else { | |
992 | int merge = 0; | |
993 | int i = skb_shinfo(skb)->nr_frags; | |
994 | struct page *page = TCP_PAGE(sk); | |
995 | int off = TCP_OFF(sk); | |
996 | ||
997 | if (skb_can_coalesce(skb, i, page, off) && | |
998 | off != PAGE_SIZE) { | |
999 | /* We can extend the last page | |
1000 | * fragment. */ | |
1001 | merge = 1; | |
def87cf4 | 1002 | } else if (i == MAX_SKB_FRAGS || !sg) { |
1da177e4 LT |
1003 | /* Need to add new fragment and cannot |
1004 | * do this because interface is non-SG, | |
1005 | * or because all the page slots are | |
1006 | * busy. */ | |
1007 | tcp_mark_push(tp, skb); | |
1008 | goto new_segment; | |
1009 | } else if (page) { | |
1da177e4 LT |
1010 | if (off == PAGE_SIZE) { |
1011 | put_page(page); | |
1012 | TCP_PAGE(sk) = page = NULL; | |
fb5f5e6e | 1013 | off = 0; |
1da177e4 | 1014 | } |
ef015786 | 1015 | } else |
fb5f5e6e | 1016 | off = 0; |
ef015786 HX |
1017 | |
1018 | if (copy > PAGE_SIZE - off) | |
1019 | copy = PAGE_SIZE - off; | |
1020 | ||
3ab224be | 1021 | if (!sk_wmem_schedule(sk, copy)) |
ef015786 | 1022 | goto wait_for_memory; |
1da177e4 LT |
1023 | |
1024 | if (!page) { | |
1025 | /* Allocate new cache page. */ | |
1026 | if (!(page = sk_stream_alloc_page(sk))) | |
1027 | goto wait_for_memory; | |
1da177e4 LT |
1028 | } |
1029 | ||
1da177e4 LT |
1030 | /* Time to copy data. We are close to |
1031 | * the end! */ | |
1032 | err = skb_copy_to_page(sk, from, skb, page, | |
1033 | off, copy); | |
1034 | if (err) { | |
1035 | /* If this page was new, give it to the | |
1036 | * socket so it does not get leaked. | |
1037 | */ | |
1038 | if (!TCP_PAGE(sk)) { | |
1039 | TCP_PAGE(sk) = page; | |
1040 | TCP_OFF(sk) = 0; | |
1041 | } | |
1042 | goto do_error; | |
1043 | } | |
1044 | ||
1045 | /* Update the skb. */ | |
1046 | if (merge) { | |
1047 | skb_shinfo(skb)->frags[i - 1].size += | |
1048 | copy; | |
1049 | } else { | |
1050 | skb_fill_page_desc(skb, i, page, off, copy); | |
1051 | if (TCP_PAGE(sk)) { | |
1052 | get_page(page); | |
1053 | } else if (off + copy < PAGE_SIZE) { | |
1054 | get_page(page); | |
1055 | TCP_PAGE(sk) = page; | |
1056 | } | |
1057 | } | |
1058 | ||
1059 | TCP_OFF(sk) = off + copy; | |
1060 | } | |
1061 | ||
1062 | if (!copied) | |
1063 | TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_PSH; | |
1064 | ||
1065 | tp->write_seq += copy; | |
1066 | TCP_SKB_CB(skb)->end_seq += copy; | |
7967168c | 1067 | skb_shinfo(skb)->gso_segs = 0; |
1da177e4 LT |
1068 | |
1069 | from += copy; | |
1070 | copied += copy; | |
1071 | if ((seglen -= copy) == 0 && iovlen == 0) | |
1072 | goto out; | |
1073 | ||
6828b92b | 1074 | if (skb->len < max || (flags & MSG_OOB)) |
1da177e4 LT |
1075 | continue; |
1076 | ||
1077 | if (forced_push(tp)) { | |
1078 | tcp_mark_push(tp, skb); | |
9e412ba7 | 1079 | __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH); |
fe067e8a | 1080 | } else if (skb == tcp_send_head(sk)) |
1da177e4 LT |
1081 | tcp_push_one(sk, mss_now); |
1082 | continue; | |
1083 | ||
1084 | wait_for_sndbuf: | |
1085 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
1086 | wait_for_memory: | |
1087 | if (copied) | |
9e412ba7 | 1088 | tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH); |
1da177e4 LT |
1089 | |
1090 | if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) | |
1091 | goto do_error; | |
1092 | ||
0c54b85f | 1093 | mss_now = tcp_send_mss(sk, &size_goal, flags); |
1da177e4 LT |
1094 | } |
1095 | } | |
1096 | ||
1097 | out: | |
1098 | if (copied) | |
9e412ba7 | 1099 | tcp_push(sk, flags, mss_now, tp->nonagle); |
1da177e4 LT |
1100 | TCP_CHECK_TIMER(sk); |
1101 | release_sock(sk); | |
1102 | return copied; | |
1103 | ||
1104 | do_fault: | |
1105 | if (!skb->len) { | |
fe067e8a DM |
1106 | tcp_unlink_write_queue(skb, sk); |
1107 | /* It is the one place in all of TCP, except connection | |
1108 | * reset, where we can be unlinking the send_head. | |
1109 | */ | |
1110 | tcp_check_send_head(sk, skb); | |
3ab224be | 1111 | sk_wmem_free_skb(sk, skb); |
1da177e4 LT |
1112 | } |
1113 | ||
1114 | do_error: | |
1115 | if (copied) | |
1116 | goto out; | |
1117 | out_err: | |
1118 | err = sk_stream_error(sk, flags, err); | |
1119 | TCP_CHECK_TIMER(sk); | |
1120 | release_sock(sk); | |
1121 | return err; | |
1122 | } | |
1123 | ||
1124 | /* | |
1125 | * Handle reading urgent data. BSD has very simple semantics for | |
1126 | * this, no blocking and very strange errors 8) | |
1127 | */ | |
1128 | ||
377f0a08 | 1129 | static int tcp_recv_urg(struct sock *sk, struct msghdr *msg, int len, int flags) |
1da177e4 LT |
1130 | { |
1131 | struct tcp_sock *tp = tcp_sk(sk); | |
1132 | ||
1133 | /* No URG data to read. */ | |
1134 | if (sock_flag(sk, SOCK_URGINLINE) || !tp->urg_data || | |
1135 | tp->urg_data == TCP_URG_READ) | |
1136 | return -EINVAL; /* Yes this is right ! */ | |
1137 | ||
1138 | if (sk->sk_state == TCP_CLOSE && !sock_flag(sk, SOCK_DONE)) | |
1139 | return -ENOTCONN; | |
1140 | ||
1141 | if (tp->urg_data & TCP_URG_VALID) { | |
1142 | int err = 0; | |
1143 | char c = tp->urg_data; | |
1144 | ||
1145 | if (!(flags & MSG_PEEK)) | |
1146 | tp->urg_data = TCP_URG_READ; | |
1147 | ||
1148 | /* Read urgent data. */ | |
1149 | msg->msg_flags |= MSG_OOB; | |
1150 | ||
1151 | if (len > 0) { | |
1152 | if (!(flags & MSG_TRUNC)) | |
1153 | err = memcpy_toiovec(msg->msg_iov, &c, 1); | |
1154 | len = 1; | |
1155 | } else | |
1156 | msg->msg_flags |= MSG_TRUNC; | |
1157 | ||
1158 | return err ? -EFAULT : len; | |
1159 | } | |
1160 | ||
1161 | if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN)) | |
1162 | return 0; | |
1163 | ||
1164 | /* Fixed the recv(..., MSG_OOB) behaviour. BSD docs and | |
1165 | * the available implementations agree in this case: | |
1166 | * this call should never block, independent of the | |
1167 | * blocking state of the socket. | |
1168 | * Mike <pall@rz.uni-karlsruhe.de> | |
1169 | */ | |
1170 | return -EAGAIN; | |
1171 | } | |
1172 | ||
1173 | /* Clean up the receive buffer for full frames taken by the user, | |
1174 | * then send an ACK if necessary. COPIED is the number of bytes | |
1175 | * tcp_recvmsg has given to the user so far, it speeds up the | |
1176 | * calculation of whether or not we must ACK for the sake of | |
1177 | * a window update. | |
1178 | */ | |
0e4b4992 | 1179 | void tcp_cleanup_rbuf(struct sock *sk, int copied) |
1da177e4 LT |
1180 | { |
1181 | struct tcp_sock *tp = tcp_sk(sk); | |
1182 | int time_to_ack = 0; | |
1183 | ||
1184 | #if TCP_DEBUG | |
1185 | struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); | |
1186 | ||
d792c100 IJ |
1187 | WARN(skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq), |
1188 | KERN_INFO "cleanup rbuf bug: copied %X seq %X rcvnxt %X\n", | |
1189 | tp->copied_seq, TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt); | |
1da177e4 LT |
1190 | #endif |
1191 | ||
463c84b9 ACM |
1192 | if (inet_csk_ack_scheduled(sk)) { |
1193 | const struct inet_connection_sock *icsk = inet_csk(sk); | |
1da177e4 LT |
1194 | /* Delayed ACKs frequently hit locked sockets during bulk |
1195 | * receive. */ | |
463c84b9 | 1196 | if (icsk->icsk_ack.blocked || |
1da177e4 | 1197 | /* Once-per-two-segments ACK was not sent by tcp_input.c */ |
463c84b9 | 1198 | tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss || |
1da177e4 LT |
1199 | /* |
1200 | * If this read emptied read buffer, we send ACK, if | |
1201 | * connection is not bidirectional, user drained | |
1202 | * receive buffer and there was a small segment | |
1203 | * in queue. | |
1204 | */ | |
1ef9696c AK |
1205 | (copied > 0 && |
1206 | ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) || | |
1207 | ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) && | |
1208 | !icsk->icsk_ack.pingpong)) && | |
1209 | !atomic_read(&sk->sk_rmem_alloc))) | |
1da177e4 LT |
1210 | time_to_ack = 1; |
1211 | } | |
1212 | ||
1213 | /* We send an ACK if we can now advertise a non-zero window | |
1214 | * which has been raised "significantly". | |
1215 | * | |
1216 | * Even if window raised up to infinity, do not send window open ACK | |
1217 | * in states, where we will not receive more. It is useless. | |
1218 | */ | |
1219 | if (copied > 0 && !time_to_ack && !(sk->sk_shutdown & RCV_SHUTDOWN)) { | |
1220 | __u32 rcv_window_now = tcp_receive_window(tp); | |
1221 | ||
1222 | /* Optimize, __tcp_select_window() is not cheap. */ | |
1223 | if (2*rcv_window_now <= tp->window_clamp) { | |
1224 | __u32 new_window = __tcp_select_window(sk); | |
1225 | ||
1226 | /* Send ACK now, if this read freed lots of space | |
1227 | * in our buffer. Certainly, new_window is new window. | |
1228 | * We can advertise it now, if it is not less than current one. | |
1229 | * "Lots" means "at least twice" here. | |
1230 | */ | |
1231 | if (new_window && new_window >= 2 * rcv_window_now) | |
1232 | time_to_ack = 1; | |
1233 | } | |
1234 | } | |
1235 | if (time_to_ack) | |
1236 | tcp_send_ack(sk); | |
1237 | } | |
1238 | ||
1239 | static void tcp_prequeue_process(struct sock *sk) | |
1240 | { | |
1241 | struct sk_buff *skb; | |
1242 | struct tcp_sock *tp = tcp_sk(sk); | |
1243 | ||
6f67c817 | 1244 | NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPPREQUEUED); |
1da177e4 LT |
1245 | |
1246 | /* RX process wants to run with disabled BHs, though it is not | |
1247 | * necessary */ | |
1248 | local_bh_disable(); | |
1249 | while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) | |
c57943a1 | 1250 | sk_backlog_rcv(sk, skb); |
1da177e4 LT |
1251 | local_bh_enable(); |
1252 | ||
1253 | /* Clear memory counter. */ | |
1254 | tp->ucopy.memory = 0; | |
1255 | } | |
1256 | ||
1257 | static inline struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off) | |
1258 | { | |
1259 | struct sk_buff *skb; | |
1260 | u32 offset; | |
1261 | ||
1262 | skb_queue_walk(&sk->sk_receive_queue, skb) { | |
1263 | offset = seq - TCP_SKB_CB(skb)->seq; | |
aa8223c7 | 1264 | if (tcp_hdr(skb)->syn) |
1da177e4 | 1265 | offset--; |
aa8223c7 | 1266 | if (offset < skb->len || tcp_hdr(skb)->fin) { |
1da177e4 LT |
1267 | *off = offset; |
1268 | return skb; | |
1269 | } | |
1270 | } | |
1271 | return NULL; | |
1272 | } | |
1273 | ||
1274 | /* | |
1275 | * This routine provides an alternative to tcp_recvmsg() for routines | |
1276 | * that would like to handle copying from skbuffs directly in 'sendfile' | |
1277 | * fashion. | |
1278 | * Note: | |
1279 | * - It is assumed that the socket was locked by the caller. | |
1280 | * - The routine does not block. | |
1281 | * - At present, there is no support for reading OOB data | |
1282 | * or for 'peeking' the socket using this routine | |
1283 | * (although both would be easy to implement). | |
1284 | */ | |
1285 | int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, | |
1286 | sk_read_actor_t recv_actor) | |
1287 | { | |
1288 | struct sk_buff *skb; | |
1289 | struct tcp_sock *tp = tcp_sk(sk); | |
1290 | u32 seq = tp->copied_seq; | |
1291 | u32 offset; | |
1292 | int copied = 0; | |
1293 | ||
1294 | if (sk->sk_state == TCP_LISTEN) | |
1295 | return -ENOTCONN; | |
1296 | while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) { | |
1297 | if (offset < skb->len) { | |
374e7b59 OP |
1298 | int used; |
1299 | size_t len; | |
1da177e4 LT |
1300 | |
1301 | len = skb->len - offset; | |
1302 | /* Stop reading if we hit a patch of urgent data */ | |
1303 | if (tp->urg_data) { | |
1304 | u32 urg_offset = tp->urg_seq - seq; | |
1305 | if (urg_offset < len) | |
1306 | len = urg_offset; | |
1307 | if (!len) | |
1308 | break; | |
1309 | } | |
1310 | used = recv_actor(desc, skb, offset, len); | |
ddb61a57 JA |
1311 | if (used < 0) { |
1312 | if (!copied) | |
1313 | copied = used; | |
1314 | break; | |
1315 | } else if (used <= len) { | |
1da177e4 LT |
1316 | seq += used; |
1317 | copied += used; | |
1318 | offset += used; | |
1319 | } | |
293ad604 OP |
1320 | /* |
1321 | * If recv_actor drops the lock (e.g. TCP splice | |
1322 | * receive) the skb pointer might be invalid when | |
1323 | * getting here: tcp_collapse might have deleted it | |
1324 | * while aggregating skbs from the socket queue. | |
1325 | */ | |
1326 | skb = tcp_recv_skb(sk, seq-1, &offset); | |
1327 | if (!skb || (offset+1 != skb->len)) | |
1da177e4 LT |
1328 | break; |
1329 | } | |
aa8223c7 | 1330 | if (tcp_hdr(skb)->fin) { |
624d1164 | 1331 | sk_eat_skb(sk, skb, 0); |
1da177e4 LT |
1332 | ++seq; |
1333 | break; | |
1334 | } | |
624d1164 | 1335 | sk_eat_skb(sk, skb, 0); |
1da177e4 LT |
1336 | if (!desc->count) |
1337 | break; | |
1338 | } | |
1339 | tp->copied_seq = seq; | |
1340 | ||
1341 | tcp_rcv_space_adjust(sk); | |
1342 | ||
1343 | /* Clean up data we have read: This will do ACK frames. */ | |
ddb61a57 | 1344 | if (copied > 0) |
0e4b4992 | 1345 | tcp_cleanup_rbuf(sk, copied); |
1da177e4 LT |
1346 | return copied; |
1347 | } | |
1348 | ||
1349 | /* | |
1350 | * This routine copies from a sock struct into the user buffer. | |
1351 | * | |
1352 | * Technical note: in 2.3 we work on _locked_ socket, so that | |
1353 | * tricks with *seq access order and skb->users are not required. | |
1354 | * Probably, code can be easily improved even more. | |
1355 | */ | |
1356 | ||
1357 | int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, | |
1358 | size_t len, int nonblock, int flags, int *addr_len) | |
1359 | { | |
1360 | struct tcp_sock *tp = tcp_sk(sk); | |
1361 | int copied = 0; | |
1362 | u32 peek_seq; | |
1363 | u32 *seq; | |
1364 | unsigned long used; | |
1365 | int err; | |
1366 | int target; /* Read at least this many bytes */ | |
1367 | long timeo; | |
1368 | struct task_struct *user_recv = NULL; | |
1a2449a8 | 1369 | int copied_early = 0; |
2b1244a4 | 1370 | struct sk_buff *skb; |
77527313 | 1371 | u32 urg_hole = 0; |
1da177e4 LT |
1372 | |
1373 | lock_sock(sk); | |
1374 | ||
1375 | TCP_CHECK_TIMER(sk); | |
1376 | ||
1377 | err = -ENOTCONN; | |
1378 | if (sk->sk_state == TCP_LISTEN) | |
1379 | goto out; | |
1380 | ||
1381 | timeo = sock_rcvtimeo(sk, nonblock); | |
1382 | ||
1383 | /* Urgent data needs to be handled specially. */ | |
1384 | if (flags & MSG_OOB) | |
1385 | goto recv_urg; | |
1386 | ||
1387 | seq = &tp->copied_seq; | |
1388 | if (flags & MSG_PEEK) { | |
1389 | peek_seq = tp->copied_seq; | |
1390 | seq = &peek_seq; | |
1391 | } | |
1392 | ||
1393 | target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); | |
1394 | ||
1a2449a8 CL |
1395 | #ifdef CONFIG_NET_DMA |
1396 | tp->ucopy.dma_chan = NULL; | |
1397 | preempt_disable(); | |
2b1244a4 | 1398 | skb = skb_peek_tail(&sk->sk_receive_queue); |
e00c5d8b AM |
1399 | { |
1400 | int available = 0; | |
1401 | ||
1402 | if (skb) | |
1403 | available = TCP_SKB_CB(skb)->seq + skb->len - (*seq); | |
1404 | if ((available < target) && | |
1405 | (len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) && | |
1406 | !sysctl_tcp_low_latency && | |
f67b4599 | 1407 | dma_find_channel(DMA_MEMCPY)) { |
e00c5d8b AM |
1408 | preempt_enable_no_resched(); |
1409 | tp->ucopy.pinned_list = | |
1410 | dma_pin_iovec_pages(msg->msg_iov, len); | |
1411 | } else { | |
1412 | preempt_enable_no_resched(); | |
1413 | } | |
1414 | } | |
1a2449a8 CL |
1415 | #endif |
1416 | ||
1da177e4 | 1417 | do { |
1da177e4 LT |
1418 | u32 offset; |
1419 | ||
1420 | /* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */ | |
1421 | if (tp->urg_data && tp->urg_seq == *seq) { | |
1422 | if (copied) | |
1423 | break; | |
1424 | if (signal_pending(current)) { | |
1425 | copied = timeo ? sock_intr_errno(timeo) : -EAGAIN; | |
1426 | break; | |
1427 | } | |
1428 | } | |
1429 | ||
1430 | /* Next get a buffer. */ | |
1431 | ||
91521944 | 1432 | skb_queue_walk(&sk->sk_receive_queue, skb) { |
1da177e4 LT |
1433 | /* Now that we have two receive queues this |
1434 | * shouldn't happen. | |
1435 | */ | |
d792c100 IJ |
1436 | if (WARN(before(*seq, TCP_SKB_CB(skb)->seq), |
1437 | KERN_INFO "recvmsg bug: copied %X " | |
1438 | "seq %X rcvnxt %X fl %X\n", *seq, | |
1439 | TCP_SKB_CB(skb)->seq, tp->rcv_nxt, | |
1440 | flags)) | |
1da177e4 | 1441 | break; |
d792c100 | 1442 | |
1da177e4 | 1443 | offset = *seq - TCP_SKB_CB(skb)->seq; |
aa8223c7 | 1444 | if (tcp_hdr(skb)->syn) |
1da177e4 LT |
1445 | offset--; |
1446 | if (offset < skb->len) | |
1447 | goto found_ok_skb; | |
aa8223c7 | 1448 | if (tcp_hdr(skb)->fin) |
1da177e4 | 1449 | goto found_fin_ok; |
c62f4c45 | 1450 | WARN(!(flags & MSG_PEEK), KERN_INFO "recvmsg bug 2: " |
d792c100 IJ |
1451 | "copied %X seq %X rcvnxt %X fl %X\n", |
1452 | *seq, TCP_SKB_CB(skb)->seq, | |
1453 | tp->rcv_nxt, flags); | |
91521944 | 1454 | } |
1da177e4 LT |
1455 | |
1456 | /* Well, if we have backlog, try to process it now yet. */ | |
1457 | ||
1458 | if (copied >= target && !sk->sk_backlog.tail) | |
1459 | break; | |
1460 | ||
1461 | if (copied) { | |
1462 | if (sk->sk_err || | |
1463 | sk->sk_state == TCP_CLOSE || | |
1464 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1465 | !timeo || | |
518a09ef | 1466 | signal_pending(current)) |
1da177e4 LT |
1467 | break; |
1468 | } else { | |
1469 | if (sock_flag(sk, SOCK_DONE)) | |
1470 | break; | |
1471 | ||
1472 | if (sk->sk_err) { | |
1473 | copied = sock_error(sk); | |
1474 | break; | |
1475 | } | |
1476 | ||
1477 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
1478 | break; | |
1479 | ||
1480 | if (sk->sk_state == TCP_CLOSE) { | |
1481 | if (!sock_flag(sk, SOCK_DONE)) { | |
1482 | /* This occurs when user tries to read | |
1483 | * from never connected socket. | |
1484 | */ | |
1485 | copied = -ENOTCONN; | |
1486 | break; | |
1487 | } | |
1488 | break; | |
1489 | } | |
1490 | ||
1491 | if (!timeo) { | |
1492 | copied = -EAGAIN; | |
1493 | break; | |
1494 | } | |
1495 | ||
1496 | if (signal_pending(current)) { | |
1497 | copied = sock_intr_errno(timeo); | |
1498 | break; | |
1499 | } | |
1500 | } | |
1501 | ||
0e4b4992 | 1502 | tcp_cleanup_rbuf(sk, copied); |
1da177e4 | 1503 | |
7df55125 | 1504 | if (!sysctl_tcp_low_latency && tp->ucopy.task == user_recv) { |
1da177e4 LT |
1505 | /* Install new reader */ |
1506 | if (!user_recv && !(flags & (MSG_TRUNC | MSG_PEEK))) { | |
1507 | user_recv = current; | |
1508 | tp->ucopy.task = user_recv; | |
1509 | tp->ucopy.iov = msg->msg_iov; | |
1510 | } | |
1511 | ||
1512 | tp->ucopy.len = len; | |
1513 | ||
547b792c IJ |
1514 | WARN_ON(tp->copied_seq != tp->rcv_nxt && |
1515 | !(flags & (MSG_PEEK | MSG_TRUNC))); | |
1da177e4 LT |
1516 | |
1517 | /* Ugly... If prequeue is not empty, we have to | |
1518 | * process it before releasing socket, otherwise | |
1519 | * order will be broken at second iteration. | |
1520 | * More elegant solution is required!!! | |
1521 | * | |
1522 | * Look: we have the following (pseudo)queues: | |
1523 | * | |
1524 | * 1. packets in flight | |
1525 | * 2. backlog | |
1526 | * 3. prequeue | |
1527 | * 4. receive_queue | |
1528 | * | |
1529 | * Each queue can be processed only if the next ones | |
1530 | * are empty. At this point we have empty receive_queue. | |
1531 | * But prequeue _can_ be not empty after 2nd iteration, | |
1532 | * when we jumped to start of loop because backlog | |
1533 | * processing added something to receive_queue. | |
1534 | * We cannot release_sock(), because backlog contains | |
1535 | * packets arrived _after_ prequeued ones. | |
1536 | * | |
1537 | * Shortly, algorithm is clear --- to process all | |
1538 | * the queues in order. We could make it more directly, | |
1539 | * requeueing packets from backlog to prequeue, if | |
1540 | * is not empty. It is more elegant, but eats cycles, | |
1541 | * unfortunately. | |
1542 | */ | |
b03efcfb | 1543 | if (!skb_queue_empty(&tp->ucopy.prequeue)) |
1da177e4 LT |
1544 | goto do_prequeue; |
1545 | ||
1546 | /* __ Set realtime policy in scheduler __ */ | |
1547 | } | |
1548 | ||
1549 | if (copied >= target) { | |
1550 | /* Do not sleep, just process backlog. */ | |
1551 | release_sock(sk); | |
1552 | lock_sock(sk); | |
1553 | } else | |
1554 | sk_wait_data(sk, &timeo); | |
1555 | ||
1a2449a8 CL |
1556 | #ifdef CONFIG_NET_DMA |
1557 | tp->ucopy.wakeup = 0; | |
1558 | #endif | |
1559 | ||
1da177e4 LT |
1560 | if (user_recv) { |
1561 | int chunk; | |
1562 | ||
1563 | /* __ Restore normal policy in scheduler __ */ | |
1564 | ||
1565 | if ((chunk = len - tp->ucopy.len) != 0) { | |
ed88098e | 1566 | NET_ADD_STATS_USER(sock_net(sk), LINUX_MIB_TCPDIRECTCOPYFROMBACKLOG, chunk); |
1da177e4 LT |
1567 | len -= chunk; |
1568 | copied += chunk; | |
1569 | } | |
1570 | ||
1571 | if (tp->rcv_nxt == tp->copied_seq && | |
b03efcfb | 1572 | !skb_queue_empty(&tp->ucopy.prequeue)) { |
1da177e4 LT |
1573 | do_prequeue: |
1574 | tcp_prequeue_process(sk); | |
1575 | ||
1576 | if ((chunk = len - tp->ucopy.len) != 0) { | |
ed88098e | 1577 | NET_ADD_STATS_USER(sock_net(sk), LINUX_MIB_TCPDIRECTCOPYFROMPREQUEUE, chunk); |
1da177e4 LT |
1578 | len -= chunk; |
1579 | copied += chunk; | |
1580 | } | |
1581 | } | |
1582 | } | |
77527313 IJ |
1583 | if ((flags & MSG_PEEK) && |
1584 | (peek_seq - copied - urg_hole != tp->copied_seq)) { | |
1da177e4 LT |
1585 | if (net_ratelimit()) |
1586 | printk(KERN_DEBUG "TCP(%s:%d): Application bug, race in MSG_PEEK.\n", | |
ba25f9dc | 1587 | current->comm, task_pid_nr(current)); |
1da177e4 LT |
1588 | peek_seq = tp->copied_seq; |
1589 | } | |
1590 | continue; | |
1591 | ||
1592 | found_ok_skb: | |
1593 | /* Ok so how much can we use? */ | |
1594 | used = skb->len - offset; | |
1595 | if (len < used) | |
1596 | used = len; | |
1597 | ||
1598 | /* Do we have urgent data here? */ | |
1599 | if (tp->urg_data) { | |
1600 | u32 urg_offset = tp->urg_seq - *seq; | |
1601 | if (urg_offset < used) { | |
1602 | if (!urg_offset) { | |
1603 | if (!sock_flag(sk, SOCK_URGINLINE)) { | |
1604 | ++*seq; | |
77527313 | 1605 | urg_hole++; |
1da177e4 LT |
1606 | offset++; |
1607 | used--; | |
1608 | if (!used) | |
1609 | goto skip_copy; | |
1610 | } | |
1611 | } else | |
1612 | used = urg_offset; | |
1613 | } | |
1614 | } | |
1615 | ||
1616 | if (!(flags & MSG_TRUNC)) { | |
1a2449a8 CL |
1617 | #ifdef CONFIG_NET_DMA |
1618 | if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) | |
f67b4599 | 1619 | tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY); |
1a2449a8 CL |
1620 | |
1621 | if (tp->ucopy.dma_chan) { | |
1622 | tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec( | |
1623 | tp->ucopy.dma_chan, skb, offset, | |
1624 | msg->msg_iov, used, | |
1625 | tp->ucopy.pinned_list); | |
1626 | ||
1627 | if (tp->ucopy.dma_cookie < 0) { | |
1628 | ||
1629 | printk(KERN_ALERT "dma_cookie < 0\n"); | |
1630 | ||
1631 | /* Exception. Bailout! */ | |
1632 | if (!copied) | |
1633 | copied = -EFAULT; | |
1634 | break; | |
1635 | } | |
1636 | if ((offset + used) == skb->len) | |
1637 | copied_early = 1; | |
1638 | ||
1639 | } else | |
1640 | #endif | |
1641 | { | |
1642 | err = skb_copy_datagram_iovec(skb, offset, | |
1643 | msg->msg_iov, used); | |
1644 | if (err) { | |
1645 | /* Exception. Bailout! */ | |
1646 | if (!copied) | |
1647 | copied = -EFAULT; | |
1648 | break; | |
1649 | } | |
1da177e4 LT |
1650 | } |
1651 | } | |
1652 | ||
1653 | *seq += used; | |
1654 | copied += used; | |
1655 | len -= used; | |
1656 | ||
1657 | tcp_rcv_space_adjust(sk); | |
1658 | ||
1659 | skip_copy: | |
1660 | if (tp->urg_data && after(tp->copied_seq, tp->urg_seq)) { | |
1661 | tp->urg_data = 0; | |
9e412ba7 | 1662 | tcp_fast_path_check(sk); |
1da177e4 LT |
1663 | } |
1664 | if (used + offset < skb->len) | |
1665 | continue; | |
1666 | ||
aa8223c7 | 1667 | if (tcp_hdr(skb)->fin) |
1da177e4 | 1668 | goto found_fin_ok; |
1a2449a8 CL |
1669 | if (!(flags & MSG_PEEK)) { |
1670 | sk_eat_skb(sk, skb, copied_early); | |
1671 | copied_early = 0; | |
1672 | } | |
1da177e4 LT |
1673 | continue; |
1674 | ||
1675 | found_fin_ok: | |
1676 | /* Process the FIN. */ | |
1677 | ++*seq; | |
1a2449a8 CL |
1678 | if (!(flags & MSG_PEEK)) { |
1679 | sk_eat_skb(sk, skb, copied_early); | |
1680 | copied_early = 0; | |
1681 | } | |
1da177e4 LT |
1682 | break; |
1683 | } while (len > 0); | |
1684 | ||
1685 | if (user_recv) { | |
b03efcfb | 1686 | if (!skb_queue_empty(&tp->ucopy.prequeue)) { |
1da177e4 LT |
1687 | int chunk; |
1688 | ||
1689 | tp->ucopy.len = copied > 0 ? len : 0; | |
1690 | ||
1691 | tcp_prequeue_process(sk); | |
1692 | ||
1693 | if (copied > 0 && (chunk = len - tp->ucopy.len) != 0) { | |
ed88098e | 1694 | NET_ADD_STATS_USER(sock_net(sk), LINUX_MIB_TCPDIRECTCOPYFROMPREQUEUE, chunk); |
1da177e4 LT |
1695 | len -= chunk; |
1696 | copied += chunk; | |
1697 | } | |
1698 | } | |
1699 | ||
1700 | tp->ucopy.task = NULL; | |
1701 | tp->ucopy.len = 0; | |
1702 | } | |
1703 | ||
1a2449a8 CL |
1704 | #ifdef CONFIG_NET_DMA |
1705 | if (tp->ucopy.dma_chan) { | |
1a2449a8 CL |
1706 | dma_cookie_t done, used; |
1707 | ||
1708 | dma_async_memcpy_issue_pending(tp->ucopy.dma_chan); | |
1709 | ||
1710 | while (dma_async_memcpy_complete(tp->ucopy.dma_chan, | |
e905a9ed YH |
1711 | tp->ucopy.dma_cookie, &done, |
1712 | &used) == DMA_IN_PROGRESS) { | |
1a2449a8 CL |
1713 | /* do partial cleanup of sk_async_wait_queue */ |
1714 | while ((skb = skb_peek(&sk->sk_async_wait_queue)) && | |
1715 | (dma_async_is_complete(skb->dma_cookie, done, | |
e905a9ed | 1716 | used) == DMA_SUCCESS)) { |
1a2449a8 CL |
1717 | __skb_dequeue(&sk->sk_async_wait_queue); |
1718 | kfree_skb(skb); | |
1719 | } | |
1720 | } | |
1721 | ||
1722 | /* Safe to free early-copied skbs now */ | |
1723 | __skb_queue_purge(&sk->sk_async_wait_queue); | |
1a2449a8 CL |
1724 | tp->ucopy.dma_chan = NULL; |
1725 | } | |
1726 | if (tp->ucopy.pinned_list) { | |
1727 | dma_unpin_iovec_pages(tp->ucopy.pinned_list); | |
1728 | tp->ucopy.pinned_list = NULL; | |
1729 | } | |
1730 | #endif | |
1731 | ||
1da177e4 LT |
1732 | /* According to UNIX98, msg_name/msg_namelen are ignored |
1733 | * on connected socket. I was just happy when found this 8) --ANK | |
1734 | */ | |
1735 | ||
1736 | /* Clean up data we have read: This will do ACK frames. */ | |
0e4b4992 | 1737 | tcp_cleanup_rbuf(sk, copied); |
1da177e4 LT |
1738 | |
1739 | TCP_CHECK_TIMER(sk); | |
1740 | release_sock(sk); | |
1741 | return copied; | |
1742 | ||
1743 | out: | |
1744 | TCP_CHECK_TIMER(sk); | |
1745 | release_sock(sk); | |
1746 | return err; | |
1747 | ||
1748 | recv_urg: | |
377f0a08 | 1749 | err = tcp_recv_urg(sk, msg, len, flags); |
1da177e4 LT |
1750 | goto out; |
1751 | } | |
1752 | ||
490d5046 IJ |
1753 | void tcp_set_state(struct sock *sk, int state) |
1754 | { | |
1755 | int oldstate = sk->sk_state; | |
1756 | ||
1757 | switch (state) { | |
1758 | case TCP_ESTABLISHED: | |
1759 | if (oldstate != TCP_ESTABLISHED) | |
81cc8a75 | 1760 | TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); |
490d5046 IJ |
1761 | break; |
1762 | ||
1763 | case TCP_CLOSE: | |
1764 | if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED) | |
81cc8a75 | 1765 | TCP_INC_STATS(sock_net(sk), TCP_MIB_ESTABRESETS); |
490d5046 IJ |
1766 | |
1767 | sk->sk_prot->unhash(sk); | |
1768 | if (inet_csk(sk)->icsk_bind_hash && | |
1769 | !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) | |
ab1e0a13 | 1770 | inet_put_port(sk); |
490d5046 IJ |
1771 | /* fall through */ |
1772 | default: | |
5a5f3a8d | 1773 | if (oldstate == TCP_ESTABLISHED) |
74688e48 | 1774 | TCP_DEC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); |
490d5046 IJ |
1775 | } |
1776 | ||
1777 | /* Change state AFTER socket is unhashed to avoid closed | |
1778 | * socket sitting in hash tables. | |
1779 | */ | |
1780 | sk->sk_state = state; | |
1781 | ||
1782 | #ifdef STATE_TRACE | |
5a5f3a8d | 1783 | SOCK_DEBUG(sk, "TCP sk=%p, State %s -> %s\n", sk, statename[oldstate], statename[state]); |
490d5046 IJ |
1784 | #endif |
1785 | } | |
1786 | EXPORT_SYMBOL_GPL(tcp_set_state); | |
1787 | ||
1da177e4 LT |
1788 | /* |
1789 | * State processing on a close. This implements the state shift for | |
1790 | * sending our FIN frame. Note that we only send a FIN for some | |
1791 | * states. A shutdown() may have already sent the FIN, or we may be | |
1792 | * closed. | |
1793 | */ | |
1794 | ||
9b5b5cff | 1795 | static const unsigned char new_state[16] = { |
1da177e4 LT |
1796 | /* current state: new state: action: */ |
1797 | /* (Invalid) */ TCP_CLOSE, | |
1798 | /* TCP_ESTABLISHED */ TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
1799 | /* TCP_SYN_SENT */ TCP_CLOSE, | |
1800 | /* TCP_SYN_RECV */ TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
1801 | /* TCP_FIN_WAIT1 */ TCP_FIN_WAIT1, | |
1802 | /* TCP_FIN_WAIT2 */ TCP_FIN_WAIT2, | |
1803 | /* TCP_TIME_WAIT */ TCP_CLOSE, | |
1804 | /* TCP_CLOSE */ TCP_CLOSE, | |
1805 | /* TCP_CLOSE_WAIT */ TCP_LAST_ACK | TCP_ACTION_FIN, | |
1806 | /* TCP_LAST_ACK */ TCP_LAST_ACK, | |
1807 | /* TCP_LISTEN */ TCP_CLOSE, | |
1808 | /* TCP_CLOSING */ TCP_CLOSING, | |
1809 | }; | |
1810 | ||
1811 | static int tcp_close_state(struct sock *sk) | |
1812 | { | |
1813 | int next = (int)new_state[sk->sk_state]; | |
1814 | int ns = next & TCP_STATE_MASK; | |
1815 | ||
1816 | tcp_set_state(sk, ns); | |
1817 | ||
1818 | return next & TCP_ACTION_FIN; | |
1819 | } | |
1820 | ||
1821 | /* | |
1822 | * Shutdown the sending side of a connection. Much like close except | |
1f29b058 | 1823 | * that we don't receive shut down or sock_set_flag(sk, SOCK_DEAD). |
1da177e4 LT |
1824 | */ |
1825 | ||
1826 | void tcp_shutdown(struct sock *sk, int how) | |
1827 | { | |
1828 | /* We need to grab some memory, and put together a FIN, | |
1829 | * and then put it into the queue to be sent. | |
1830 | * Tim MacKenzie(tym@dibbler.cs.monash.edu.au) 4 Dec '92. | |
1831 | */ | |
1832 | if (!(how & SEND_SHUTDOWN)) | |
1833 | return; | |
1834 | ||
1835 | /* If we've already sent a FIN, or it's a closed state, skip this. */ | |
1836 | if ((1 << sk->sk_state) & | |
1837 | (TCPF_ESTABLISHED | TCPF_SYN_SENT | | |
1838 | TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) { | |
1839 | /* Clear out any half completed packets. FIN if needed. */ | |
1840 | if (tcp_close_state(sk)) | |
1841 | tcp_send_fin(sk); | |
1842 | } | |
1843 | } | |
1844 | ||
1da177e4 LT |
1845 | void tcp_close(struct sock *sk, long timeout) |
1846 | { | |
1847 | struct sk_buff *skb; | |
1848 | int data_was_unread = 0; | |
75c2d907 | 1849 | int state; |
1da177e4 LT |
1850 | |
1851 | lock_sock(sk); | |
1852 | sk->sk_shutdown = SHUTDOWN_MASK; | |
1853 | ||
1854 | if (sk->sk_state == TCP_LISTEN) { | |
1855 | tcp_set_state(sk, TCP_CLOSE); | |
1856 | ||
1857 | /* Special case. */ | |
0a5578cf | 1858 | inet_csk_listen_stop(sk); |
1da177e4 LT |
1859 | |
1860 | goto adjudge_to_death; | |
1861 | } | |
1862 | ||
1863 | /* We need to flush the recv. buffs. We do this only on the | |
1864 | * descriptor close, not protocol-sourced closes, because the | |
1865 | * reader process may not have drained the data yet! | |
1866 | */ | |
1867 | while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { | |
1868 | u32 len = TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq - | |
aa8223c7 | 1869 | tcp_hdr(skb)->fin; |
1da177e4 LT |
1870 | data_was_unread += len; |
1871 | __kfree_skb(skb); | |
1872 | } | |
1873 | ||
3ab224be | 1874 | sk_mem_reclaim(sk); |
1da177e4 | 1875 | |
65bb723c GR |
1876 | /* As outlined in RFC 2525, section 2.17, we send a RST here because |
1877 | * data was lost. To witness the awful effects of the old behavior of | |
1878 | * always doing a FIN, run an older 2.1.x kernel or 2.0.x, start a bulk | |
1879 | * GET in an FTP client, suspend the process, wait for the client to | |
1880 | * advertise a zero window, then kill -9 the FTP client, wheee... | |
1881 | * Note: timeout is always zero in such a case. | |
1da177e4 LT |
1882 | */ |
1883 | if (data_was_unread) { | |
1884 | /* Unread data was tossed, zap the connection. */ | |
6f67c817 | 1885 | NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE); |
1da177e4 | 1886 | tcp_set_state(sk, TCP_CLOSE); |
aa133076 | 1887 | tcp_send_active_reset(sk, sk->sk_allocation); |
1da177e4 LT |
1888 | } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { |
1889 | /* Check zero linger _after_ checking for unread data. */ | |
1890 | sk->sk_prot->disconnect(sk, 0); | |
6f67c817 | 1891 | NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPABORTONDATA); |
1da177e4 LT |
1892 | } else if (tcp_close_state(sk)) { |
1893 | /* We FIN if the application ate all the data before | |
1894 | * zapping the connection. | |
1895 | */ | |
1896 | ||
1897 | /* RED-PEN. Formally speaking, we have broken TCP state | |
1898 | * machine. State transitions: | |
1899 | * | |
1900 | * TCP_ESTABLISHED -> TCP_FIN_WAIT1 | |
1901 | * TCP_SYN_RECV -> TCP_FIN_WAIT1 (forget it, it's impossible) | |
1902 | * TCP_CLOSE_WAIT -> TCP_LAST_ACK | |
1903 | * | |
1904 | * are legal only when FIN has been sent (i.e. in window), | |
1905 | * rather than queued out of window. Purists blame. | |
1906 | * | |
1907 | * F.e. "RFC state" is ESTABLISHED, | |
1908 | * if Linux state is FIN-WAIT-1, but FIN is still not sent. | |
1909 | * | |
1910 | * The visible declinations are that sometimes | |
1911 | * we enter time-wait state, when it is not required really | |
1912 | * (harmless), do not send active resets, when they are | |
1913 | * required by specs (TCP_ESTABLISHED, TCP_CLOSE_WAIT, when | |
1914 | * they look as CLOSING or LAST_ACK for Linux) | |
1915 | * Probably, I missed some more holelets. | |
1916 | * --ANK | |
1917 | */ | |
1918 | tcp_send_fin(sk); | |
1919 | } | |
1920 | ||
1921 | sk_stream_wait_close(sk, timeout); | |
1922 | ||
1923 | adjudge_to_death: | |
75c2d907 HX |
1924 | state = sk->sk_state; |
1925 | sock_hold(sk); | |
1926 | sock_orphan(sk); | |
75c2d907 | 1927 | |
1da177e4 LT |
1928 | /* It is the last release_sock in its life. It will remove backlog. */ |
1929 | release_sock(sk); | |
1930 | ||
1931 | ||
1932 | /* Now socket is owned by kernel and we acquire BH lock | |
1933 | to finish close. No need to check for user refs. | |
1934 | */ | |
1935 | local_bh_disable(); | |
1936 | bh_lock_sock(sk); | |
547b792c | 1937 | WARN_ON(sock_owned_by_user(sk)); |
1da177e4 | 1938 | |
eb4dea58 HX |
1939 | percpu_counter_inc(sk->sk_prot->orphan_count); |
1940 | ||
75c2d907 HX |
1941 | /* Have we already been destroyed by a softirq or backlog? */ |
1942 | if (state != TCP_CLOSE && sk->sk_state == TCP_CLOSE) | |
1943 | goto out; | |
1da177e4 LT |
1944 | |
1945 | /* This is a (useful) BSD violating of the RFC. There is a | |
1946 | * problem with TCP as specified in that the other end could | |
1947 | * keep a socket open forever with no application left this end. | |
1948 | * We use a 3 minute timeout (about the same as BSD) then kill | |
1949 | * our end. If they send after that then tough - BUT: long enough | |
1950 | * that we won't make the old 4*rto = almost no time - whoops | |
1951 | * reset mistake. | |
1952 | * | |
1953 | * Nope, it was not mistake. It is really desired behaviour | |
1954 | * f.e. on http servers, when such sockets are useless, but | |
1955 | * consume significant resources. Let's do it with special | |
1956 | * linger2 option. --ANK | |
1957 | */ | |
1958 | ||
1959 | if (sk->sk_state == TCP_FIN_WAIT2) { | |
1960 | struct tcp_sock *tp = tcp_sk(sk); | |
1961 | if (tp->linger2 < 0) { | |
1962 | tcp_set_state(sk, TCP_CLOSE); | |
1963 | tcp_send_active_reset(sk, GFP_ATOMIC); | |
de0744af PE |
1964 | NET_INC_STATS_BH(sock_net(sk), |
1965 | LINUX_MIB_TCPABORTONLINGER); | |
1da177e4 | 1966 | } else { |
463c84b9 | 1967 | const int tmo = tcp_fin_time(sk); |
1da177e4 LT |
1968 | |
1969 | if (tmo > TCP_TIMEWAIT_LEN) { | |
52499afe DM |
1970 | inet_csk_reset_keepalive_timer(sk, |
1971 | tmo - TCP_TIMEWAIT_LEN); | |
1da177e4 | 1972 | } else { |
1da177e4 LT |
1973 | tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); |
1974 | goto out; | |
1975 | } | |
1976 | } | |
1977 | } | |
1978 | if (sk->sk_state != TCP_CLOSE) { | |
dd24c001 ED |
1979 | int orphan_count = percpu_counter_read_positive( |
1980 | sk->sk_prot->orphan_count); | |
1981 | ||
3ab224be | 1982 | sk_mem_reclaim(sk); |
dd24c001 | 1983 | if (tcp_too_many_orphans(sk, orphan_count)) { |
1da177e4 LT |
1984 | if (net_ratelimit()) |
1985 | printk(KERN_INFO "TCP: too many of orphaned " | |
1986 | "sockets\n"); | |
1987 | tcp_set_state(sk, TCP_CLOSE); | |
1988 | tcp_send_active_reset(sk, GFP_ATOMIC); | |
de0744af PE |
1989 | NET_INC_STATS_BH(sock_net(sk), |
1990 | LINUX_MIB_TCPABORTONMEMORY); | |
1da177e4 LT |
1991 | } |
1992 | } | |
1da177e4 LT |
1993 | |
1994 | if (sk->sk_state == TCP_CLOSE) | |
0a5578cf | 1995 | inet_csk_destroy_sock(sk); |
1da177e4 LT |
1996 | /* Otherwise, socket is reprieved until protocol close. */ |
1997 | ||
1998 | out: | |
1999 | bh_unlock_sock(sk); | |
2000 | local_bh_enable(); | |
2001 | sock_put(sk); | |
2002 | } | |
2003 | ||
2004 | /* These states need RST on ABORT according to RFC793 */ | |
2005 | ||
2006 | static inline int tcp_need_reset(int state) | |
2007 | { | |
2008 | return (1 << state) & | |
2009 | (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 | | |
2010 | TCPF_FIN_WAIT2 | TCPF_SYN_RECV); | |
2011 | } | |
2012 | ||
2013 | int tcp_disconnect(struct sock *sk, int flags) | |
2014 | { | |
2015 | struct inet_sock *inet = inet_sk(sk); | |
463c84b9 | 2016 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
2017 | struct tcp_sock *tp = tcp_sk(sk); |
2018 | int err = 0; | |
2019 | int old_state = sk->sk_state; | |
2020 | ||
2021 | if (old_state != TCP_CLOSE) | |
2022 | tcp_set_state(sk, TCP_CLOSE); | |
2023 | ||
2024 | /* ABORT function of RFC793 */ | |
2025 | if (old_state == TCP_LISTEN) { | |
0a5578cf | 2026 | inet_csk_listen_stop(sk); |
1da177e4 LT |
2027 | } else if (tcp_need_reset(old_state) || |
2028 | (tp->snd_nxt != tp->write_seq && | |
2029 | (1 << old_state) & (TCPF_CLOSING | TCPF_LAST_ACK))) { | |
caa20d9a | 2030 | /* The last check adjusts for discrepancy of Linux wrt. RFC |
1da177e4 LT |
2031 | * states |
2032 | */ | |
2033 | tcp_send_active_reset(sk, gfp_any()); | |
2034 | sk->sk_err = ECONNRESET; | |
2035 | } else if (old_state == TCP_SYN_SENT) | |
2036 | sk->sk_err = ECONNRESET; | |
2037 | ||
2038 | tcp_clear_xmit_timers(sk); | |
2039 | __skb_queue_purge(&sk->sk_receive_queue); | |
fe067e8a | 2040 | tcp_write_queue_purge(sk); |
1da177e4 | 2041 | __skb_queue_purge(&tp->out_of_order_queue); |
1a2449a8 CL |
2042 | #ifdef CONFIG_NET_DMA |
2043 | __skb_queue_purge(&sk->sk_async_wait_queue); | |
2044 | #endif | |
1da177e4 | 2045 | |
c720c7e8 | 2046 | inet->inet_dport = 0; |
1da177e4 LT |
2047 | |
2048 | if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) | |
2049 | inet_reset_saddr(sk); | |
2050 | ||
2051 | sk->sk_shutdown = 0; | |
2052 | sock_reset_flag(sk, SOCK_DONE); | |
2053 | tp->srtt = 0; | |
2054 | if ((tp->write_seq += tp->max_window + 2) == 0) | |
2055 | tp->write_seq = 1; | |
463c84b9 | 2056 | icsk->icsk_backoff = 0; |
1da177e4 | 2057 | tp->snd_cwnd = 2; |
6687e988 | 2058 | icsk->icsk_probes_out = 0; |
1da177e4 | 2059 | tp->packets_out = 0; |
0b6a05c1 | 2060 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; |
1da177e4 | 2061 | tp->snd_cwnd_cnt = 0; |
9772efb9 | 2062 | tp->bytes_acked = 0; |
1fdf475a | 2063 | tp->window_clamp = 0; |
6687e988 | 2064 | tcp_set_ca_state(sk, TCP_CA_Open); |
1da177e4 | 2065 | tcp_clear_retrans(tp); |
463c84b9 | 2066 | inet_csk_delack_init(sk); |
fe067e8a | 2067 | tcp_init_send_head(sk); |
b40b4f79 | 2068 | memset(&tp->rx_opt, 0, sizeof(tp->rx_opt)); |
1da177e4 LT |
2069 | __sk_dst_reset(sk); |
2070 | ||
c720c7e8 | 2071 | WARN_ON(inet->inet_num && !icsk->icsk_bind_hash); |
1da177e4 LT |
2072 | |
2073 | sk->sk_error_report(sk); | |
2074 | return err; | |
2075 | } | |
2076 | ||
1da177e4 LT |
2077 | /* |
2078 | * Socket option code for TCP. | |
2079 | */ | |
3fdadf7d | 2080 | static int do_tcp_setsockopt(struct sock *sk, int level, |
b7058842 | 2081 | int optname, char __user *optval, unsigned int optlen) |
1da177e4 LT |
2082 | { |
2083 | struct tcp_sock *tp = tcp_sk(sk); | |
463c84b9 | 2084 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
2085 | int val; |
2086 | int err = 0; | |
2087 | ||
e56fb50f WAS |
2088 | /* These are data/string values, all the others are ints */ |
2089 | switch (optname) { | |
2090 | case TCP_CONGESTION: { | |
5f8ef48d SH |
2091 | char name[TCP_CA_NAME_MAX]; |
2092 | ||
2093 | if (optlen < 1) | |
2094 | return -EINVAL; | |
2095 | ||
2096 | val = strncpy_from_user(name, optval, | |
4fdb78d3 | 2097 | min_t(long, TCP_CA_NAME_MAX-1, optlen)); |
5f8ef48d SH |
2098 | if (val < 0) |
2099 | return -EFAULT; | |
2100 | name[val] = 0; | |
2101 | ||
2102 | lock_sock(sk); | |
6687e988 | 2103 | err = tcp_set_congestion_control(sk, name); |
5f8ef48d SH |
2104 | release_sock(sk); |
2105 | return err; | |
2106 | } | |
e56fb50f WAS |
2107 | case TCP_COOKIE_TRANSACTIONS: { |
2108 | struct tcp_cookie_transactions ctd; | |
2109 | struct tcp_cookie_values *cvp = NULL; | |
2110 | ||
2111 | if (sizeof(ctd) > optlen) | |
2112 | return -EINVAL; | |
2113 | if (copy_from_user(&ctd, optval, sizeof(ctd))) | |
2114 | return -EFAULT; | |
2115 | ||
2116 | if (ctd.tcpct_used > sizeof(ctd.tcpct_value) || | |
2117 | ctd.tcpct_s_data_desired > TCP_MSS_DESIRED) | |
2118 | return -EINVAL; | |
2119 | ||
2120 | if (ctd.tcpct_cookie_desired == 0) { | |
2121 | /* default to global value */ | |
2122 | } else if ((0x1 & ctd.tcpct_cookie_desired) || | |
2123 | ctd.tcpct_cookie_desired > TCP_COOKIE_MAX || | |
2124 | ctd.tcpct_cookie_desired < TCP_COOKIE_MIN) { | |
2125 | return -EINVAL; | |
2126 | } | |
2127 | ||
2128 | if (TCP_COOKIE_OUT_NEVER & ctd.tcpct_flags) { | |
2129 | /* Supercedes all other values */ | |
2130 | lock_sock(sk); | |
2131 | if (tp->cookie_values != NULL) { | |
2132 | kref_put(&tp->cookie_values->kref, | |
2133 | tcp_cookie_values_release); | |
2134 | tp->cookie_values = NULL; | |
2135 | } | |
2136 | tp->rx_opt.cookie_in_always = 0; /* false */ | |
2137 | tp->rx_opt.cookie_out_never = 1; /* true */ | |
2138 | release_sock(sk); | |
2139 | return err; | |
2140 | } | |
2141 | ||
2142 | /* Allocate ancillary memory before locking. | |
2143 | */ | |
2144 | if (ctd.tcpct_used > 0 || | |
2145 | (tp->cookie_values == NULL && | |
2146 | (sysctl_tcp_cookie_size > 0 || | |
2147 | ctd.tcpct_cookie_desired > 0 || | |
2148 | ctd.tcpct_s_data_desired > 0))) { | |
2149 | cvp = kzalloc(sizeof(*cvp) + ctd.tcpct_used, | |
2150 | GFP_KERNEL); | |
2151 | if (cvp == NULL) | |
2152 | return -ENOMEM; | |
2153 | } | |
2154 | lock_sock(sk); | |
2155 | tp->rx_opt.cookie_in_always = | |
2156 | (TCP_COOKIE_IN_ALWAYS & ctd.tcpct_flags); | |
2157 | tp->rx_opt.cookie_out_never = 0; /* false */ | |
2158 | ||
2159 | if (tp->cookie_values != NULL) { | |
2160 | if (cvp != NULL) { | |
2161 | /* Changed values are recorded by a changed | |
2162 | * pointer, ensuring the cookie will differ, | |
2163 | * without separately hashing each value later. | |
2164 | */ | |
2165 | kref_put(&tp->cookie_values->kref, | |
2166 | tcp_cookie_values_release); | |
2167 | kref_init(&cvp->kref); | |
2168 | tp->cookie_values = cvp; | |
2169 | } else { | |
2170 | cvp = tp->cookie_values; | |
2171 | } | |
2172 | } | |
2173 | if (cvp != NULL) { | |
2174 | cvp->cookie_desired = ctd.tcpct_cookie_desired; | |
2175 | ||
2176 | if (ctd.tcpct_used > 0) { | |
2177 | memcpy(cvp->s_data_payload, ctd.tcpct_value, | |
2178 | ctd.tcpct_used); | |
2179 | cvp->s_data_desired = ctd.tcpct_used; | |
2180 | cvp->s_data_constant = 1; /* true */ | |
2181 | } else { | |
2182 | /* No constant payload data. */ | |
2183 | cvp->s_data_desired = ctd.tcpct_s_data_desired; | |
2184 | cvp->s_data_constant = 0; /* false */ | |
2185 | } | |
2186 | } | |
2187 | release_sock(sk); | |
2188 | return err; | |
2189 | } | |
2190 | default: | |
2191 | /* fallthru */ | |
2192 | break; | |
2193 | }; | |
5f8ef48d | 2194 | |
1da177e4 LT |
2195 | if (optlen < sizeof(int)) |
2196 | return -EINVAL; | |
2197 | ||
2198 | if (get_user(val, (int __user *)optval)) | |
2199 | return -EFAULT; | |
2200 | ||
2201 | lock_sock(sk); | |
2202 | ||
2203 | switch (optname) { | |
2204 | case TCP_MAXSEG: | |
2205 | /* Values greater than interface MTU won't take effect. However | |
2206 | * at the point when this call is done we typically don't yet | |
2207 | * know which interface is going to be used */ | |
2208 | if (val < 8 || val > MAX_TCP_WINDOW) { | |
2209 | err = -EINVAL; | |
2210 | break; | |
2211 | } | |
2212 | tp->rx_opt.user_mss = val; | |
2213 | break; | |
2214 | ||
2215 | case TCP_NODELAY: | |
2216 | if (val) { | |
2217 | /* TCP_NODELAY is weaker than TCP_CORK, so that | |
2218 | * this option on corked socket is remembered, but | |
2219 | * it is not activated until cork is cleared. | |
2220 | * | |
2221 | * However, when TCP_NODELAY is set we make | |
2222 | * an explicit push, which overrides even TCP_CORK | |
2223 | * for currently queued segments. | |
2224 | */ | |
2225 | tp->nonagle |= TCP_NAGLE_OFF|TCP_NAGLE_PUSH; | |
9e412ba7 | 2226 | tcp_push_pending_frames(sk); |
1da177e4 LT |
2227 | } else { |
2228 | tp->nonagle &= ~TCP_NAGLE_OFF; | |
2229 | } | |
2230 | break; | |
2231 | ||
2232 | case TCP_CORK: | |
2233 | /* When set indicates to always queue non-full frames. | |
2234 | * Later the user clears this option and we transmit | |
2235 | * any pending partial frames in the queue. This is | |
2236 | * meant to be used alongside sendfile() to get properly | |
2237 | * filled frames when the user (for example) must write | |
2238 | * out headers with a write() call first and then use | |
2239 | * sendfile to send out the data parts. | |
2240 | * | |
2241 | * TCP_CORK can be set together with TCP_NODELAY and it is | |
2242 | * stronger than TCP_NODELAY. | |
2243 | */ | |
2244 | if (val) { | |
2245 | tp->nonagle |= TCP_NAGLE_CORK; | |
2246 | } else { | |
2247 | tp->nonagle &= ~TCP_NAGLE_CORK; | |
2248 | if (tp->nonagle&TCP_NAGLE_OFF) | |
2249 | tp->nonagle |= TCP_NAGLE_PUSH; | |
9e412ba7 | 2250 | tcp_push_pending_frames(sk); |
1da177e4 LT |
2251 | } |
2252 | break; | |
2253 | ||
2254 | case TCP_KEEPIDLE: | |
2255 | if (val < 1 || val > MAX_TCP_KEEPIDLE) | |
2256 | err = -EINVAL; | |
2257 | else { | |
2258 | tp->keepalive_time = val * HZ; | |
2259 | if (sock_flag(sk, SOCK_KEEPOPEN) && | |
2260 | !((1 << sk->sk_state) & | |
2261 | (TCPF_CLOSE | TCPF_LISTEN))) { | |
2262 | __u32 elapsed = tcp_time_stamp - tp->rcv_tstamp; | |
2263 | if (tp->keepalive_time > elapsed) | |
2264 | elapsed = tp->keepalive_time - elapsed; | |
2265 | else | |
2266 | elapsed = 0; | |
463c84b9 | 2267 | inet_csk_reset_keepalive_timer(sk, elapsed); |
1da177e4 LT |
2268 | } |
2269 | } | |
2270 | break; | |
2271 | case TCP_KEEPINTVL: | |
2272 | if (val < 1 || val > MAX_TCP_KEEPINTVL) | |
2273 | err = -EINVAL; | |
2274 | else | |
2275 | tp->keepalive_intvl = val * HZ; | |
2276 | break; | |
2277 | case TCP_KEEPCNT: | |
2278 | if (val < 1 || val > MAX_TCP_KEEPCNT) | |
2279 | err = -EINVAL; | |
2280 | else | |
2281 | tp->keepalive_probes = val; | |
2282 | break; | |
2283 | case TCP_SYNCNT: | |
2284 | if (val < 1 || val > MAX_TCP_SYNCNT) | |
2285 | err = -EINVAL; | |
2286 | else | |
463c84b9 | 2287 | icsk->icsk_syn_retries = val; |
1da177e4 LT |
2288 | break; |
2289 | ||
2290 | case TCP_LINGER2: | |
2291 | if (val < 0) | |
2292 | tp->linger2 = -1; | |
2293 | else if (val > sysctl_tcp_fin_timeout / HZ) | |
2294 | tp->linger2 = 0; | |
2295 | else | |
2296 | tp->linger2 = val * HZ; | |
2297 | break; | |
2298 | ||
2299 | case TCP_DEFER_ACCEPT: | |
b103cf34 JA |
2300 | /* Translate value in seconds to number of retransmits */ |
2301 | icsk->icsk_accept_queue.rskq_defer_accept = | |
2302 | secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ, | |
2303 | TCP_RTO_MAX / HZ); | |
1da177e4 LT |
2304 | break; |
2305 | ||
2306 | case TCP_WINDOW_CLAMP: | |
2307 | if (!val) { | |
2308 | if (sk->sk_state != TCP_CLOSE) { | |
2309 | err = -EINVAL; | |
2310 | break; | |
2311 | } | |
2312 | tp->window_clamp = 0; | |
2313 | } else | |
2314 | tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ? | |
2315 | SOCK_MIN_RCVBUF / 2 : val; | |
2316 | break; | |
2317 | ||
2318 | case TCP_QUICKACK: | |
2319 | if (!val) { | |
463c84b9 | 2320 | icsk->icsk_ack.pingpong = 1; |
1da177e4 | 2321 | } else { |
463c84b9 | 2322 | icsk->icsk_ack.pingpong = 0; |
1da177e4 LT |
2323 | if ((1 << sk->sk_state) & |
2324 | (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) && | |
463c84b9 ACM |
2325 | inet_csk_ack_scheduled(sk)) { |
2326 | icsk->icsk_ack.pending |= ICSK_ACK_PUSHED; | |
0e4b4992 | 2327 | tcp_cleanup_rbuf(sk, 1); |
1da177e4 | 2328 | if (!(val & 1)) |
463c84b9 | 2329 | icsk->icsk_ack.pingpong = 1; |
1da177e4 LT |
2330 | } |
2331 | } | |
2332 | break; | |
2333 | ||
cfb6eeb4 YH |
2334 | #ifdef CONFIG_TCP_MD5SIG |
2335 | case TCP_MD5SIG: | |
2336 | /* Read the IP->Key mappings from userspace */ | |
2337 | err = tp->af_specific->md5_parse(sk, optval, optlen); | |
2338 | break; | |
2339 | #endif | |
2340 | ||
1da177e4 LT |
2341 | default: |
2342 | err = -ENOPROTOOPT; | |
2343 | break; | |
3ff50b79 SH |
2344 | } |
2345 | ||
1da177e4 LT |
2346 | release_sock(sk); |
2347 | return err; | |
2348 | } | |
2349 | ||
3fdadf7d | 2350 | int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval, |
b7058842 | 2351 | unsigned int optlen) |
3fdadf7d DM |
2352 | { |
2353 | struct inet_connection_sock *icsk = inet_csk(sk); | |
2354 | ||
2355 | if (level != SOL_TCP) | |
2356 | return icsk->icsk_af_ops->setsockopt(sk, level, optname, | |
2357 | optval, optlen); | |
2358 | return do_tcp_setsockopt(sk, level, optname, optval, optlen); | |
2359 | } | |
2360 | ||
2361 | #ifdef CONFIG_COMPAT | |
543d9cfe | 2362 | int compat_tcp_setsockopt(struct sock *sk, int level, int optname, |
b7058842 | 2363 | char __user *optval, unsigned int optlen) |
3fdadf7d | 2364 | { |
dec73ff0 ACM |
2365 | if (level != SOL_TCP) |
2366 | return inet_csk_compat_setsockopt(sk, level, optname, | |
2367 | optval, optlen); | |
3fdadf7d DM |
2368 | return do_tcp_setsockopt(sk, level, optname, optval, optlen); |
2369 | } | |
543d9cfe ACM |
2370 | |
2371 | EXPORT_SYMBOL(compat_tcp_setsockopt); | |
3fdadf7d DM |
2372 | #endif |
2373 | ||
1da177e4 LT |
2374 | /* Return information about state of tcp endpoint in API format. */ |
2375 | void tcp_get_info(struct sock *sk, struct tcp_info *info) | |
2376 | { | |
2377 | struct tcp_sock *tp = tcp_sk(sk); | |
463c84b9 | 2378 | const struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
2379 | u32 now = tcp_time_stamp; |
2380 | ||
2381 | memset(info, 0, sizeof(*info)); | |
2382 | ||
2383 | info->tcpi_state = sk->sk_state; | |
6687e988 | 2384 | info->tcpi_ca_state = icsk->icsk_ca_state; |
463c84b9 | 2385 | info->tcpi_retransmits = icsk->icsk_retransmits; |
6687e988 | 2386 | info->tcpi_probes = icsk->icsk_probes_out; |
463c84b9 | 2387 | info->tcpi_backoff = icsk->icsk_backoff; |
1da177e4 LT |
2388 | |
2389 | if (tp->rx_opt.tstamp_ok) | |
2390 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; | |
e60402d0 | 2391 | if (tcp_is_sack(tp)) |
1da177e4 LT |
2392 | info->tcpi_options |= TCPI_OPT_SACK; |
2393 | if (tp->rx_opt.wscale_ok) { | |
2394 | info->tcpi_options |= TCPI_OPT_WSCALE; | |
2395 | info->tcpi_snd_wscale = tp->rx_opt.snd_wscale; | |
2396 | info->tcpi_rcv_wscale = tp->rx_opt.rcv_wscale; | |
e905a9ed | 2397 | } |
1da177e4 LT |
2398 | |
2399 | if (tp->ecn_flags&TCP_ECN_OK) | |
2400 | info->tcpi_options |= TCPI_OPT_ECN; | |
2401 | ||
463c84b9 ACM |
2402 | info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto); |
2403 | info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato); | |
c1b4a7e6 | 2404 | info->tcpi_snd_mss = tp->mss_cache; |
463c84b9 | 2405 | info->tcpi_rcv_mss = icsk->icsk_ack.rcv_mss; |
1da177e4 | 2406 | |
5ee3afba RJ |
2407 | if (sk->sk_state == TCP_LISTEN) { |
2408 | info->tcpi_unacked = sk->sk_ack_backlog; | |
2409 | info->tcpi_sacked = sk->sk_max_ack_backlog; | |
2410 | } else { | |
2411 | info->tcpi_unacked = tp->packets_out; | |
2412 | info->tcpi_sacked = tp->sacked_out; | |
2413 | } | |
1da177e4 LT |
2414 | info->tcpi_lost = tp->lost_out; |
2415 | info->tcpi_retrans = tp->retrans_out; | |
2416 | info->tcpi_fackets = tp->fackets_out; | |
2417 | ||
2418 | info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime); | |
463c84b9 | 2419 | info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime); |
1da177e4 LT |
2420 | info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp); |
2421 | ||
d83d8461 | 2422 | info->tcpi_pmtu = icsk->icsk_pmtu_cookie; |
1da177e4 LT |
2423 | info->tcpi_rcv_ssthresh = tp->rcv_ssthresh; |
2424 | info->tcpi_rtt = jiffies_to_usecs(tp->srtt)>>3; | |
2425 | info->tcpi_rttvar = jiffies_to_usecs(tp->mdev)>>2; | |
2426 | info->tcpi_snd_ssthresh = tp->snd_ssthresh; | |
2427 | info->tcpi_snd_cwnd = tp->snd_cwnd; | |
2428 | info->tcpi_advmss = tp->advmss; | |
2429 | info->tcpi_reordering = tp->reordering; | |
2430 | ||
2431 | info->tcpi_rcv_rtt = jiffies_to_usecs(tp->rcv_rtt_est.rtt)>>3; | |
2432 | info->tcpi_rcv_space = tp->rcvq_space.space; | |
2433 | ||
2434 | info->tcpi_total_retrans = tp->total_retrans; | |
2435 | } | |
2436 | ||
2437 | EXPORT_SYMBOL_GPL(tcp_get_info); | |
2438 | ||
3fdadf7d DM |
2439 | static int do_tcp_getsockopt(struct sock *sk, int level, |
2440 | int optname, char __user *optval, int __user *optlen) | |
1da177e4 | 2441 | { |
295f7324 | 2442 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 LT |
2443 | struct tcp_sock *tp = tcp_sk(sk); |
2444 | int val, len; | |
2445 | ||
1da177e4 LT |
2446 | if (get_user(len, optlen)) |
2447 | return -EFAULT; | |
2448 | ||
2449 | len = min_t(unsigned int, len, sizeof(int)); | |
2450 | ||
2451 | if (len < 0) | |
2452 | return -EINVAL; | |
2453 | ||
2454 | switch (optname) { | |
2455 | case TCP_MAXSEG: | |
c1b4a7e6 | 2456 | val = tp->mss_cache; |
1da177e4 LT |
2457 | if (!val && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) |
2458 | val = tp->rx_opt.user_mss; | |
2459 | break; | |
2460 | case TCP_NODELAY: | |
2461 | val = !!(tp->nonagle&TCP_NAGLE_OFF); | |
2462 | break; | |
2463 | case TCP_CORK: | |
2464 | val = !!(tp->nonagle&TCP_NAGLE_CORK); | |
2465 | break; | |
2466 | case TCP_KEEPIDLE: | |
df19a626 | 2467 | val = keepalive_time_when(tp) / HZ; |
1da177e4 LT |
2468 | break; |
2469 | case TCP_KEEPINTVL: | |
df19a626 | 2470 | val = keepalive_intvl_when(tp) / HZ; |
1da177e4 LT |
2471 | break; |
2472 | case TCP_KEEPCNT: | |
df19a626 | 2473 | val = keepalive_probes(tp); |
1da177e4 LT |
2474 | break; |
2475 | case TCP_SYNCNT: | |
295f7324 | 2476 | val = icsk->icsk_syn_retries ? : sysctl_tcp_syn_retries; |
1da177e4 LT |
2477 | break; |
2478 | case TCP_LINGER2: | |
2479 | val = tp->linger2; | |
2480 | if (val >= 0) | |
2481 | val = (val ? : sysctl_tcp_fin_timeout) / HZ; | |
2482 | break; | |
2483 | case TCP_DEFER_ACCEPT: | |
b103cf34 JA |
2484 | val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept, |
2485 | TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ); | |
1da177e4 LT |
2486 | break; |
2487 | case TCP_WINDOW_CLAMP: | |
2488 | val = tp->window_clamp; | |
2489 | break; | |
2490 | case TCP_INFO: { | |
2491 | struct tcp_info info; | |
2492 | ||
2493 | if (get_user(len, optlen)) | |
2494 | return -EFAULT; | |
2495 | ||
2496 | tcp_get_info(sk, &info); | |
2497 | ||
2498 | len = min_t(unsigned int, len, sizeof(info)); | |
2499 | if (put_user(len, optlen)) | |
2500 | return -EFAULT; | |
2501 | if (copy_to_user(optval, &info, len)) | |
2502 | return -EFAULT; | |
2503 | return 0; | |
2504 | } | |
2505 | case TCP_QUICKACK: | |
295f7324 | 2506 | val = !icsk->icsk_ack.pingpong; |
1da177e4 | 2507 | break; |
5f8ef48d SH |
2508 | |
2509 | case TCP_CONGESTION: | |
2510 | if (get_user(len, optlen)) | |
2511 | return -EFAULT; | |
2512 | len = min_t(unsigned int, len, TCP_CA_NAME_MAX); | |
2513 | if (put_user(len, optlen)) | |
2514 | return -EFAULT; | |
6687e988 | 2515 | if (copy_to_user(optval, icsk->icsk_ca_ops->name, len)) |
5f8ef48d SH |
2516 | return -EFAULT; |
2517 | return 0; | |
e56fb50f WAS |
2518 | |
2519 | case TCP_COOKIE_TRANSACTIONS: { | |
2520 | struct tcp_cookie_transactions ctd; | |
2521 | struct tcp_cookie_values *cvp = tp->cookie_values; | |
2522 | ||
2523 | if (get_user(len, optlen)) | |
2524 | return -EFAULT; | |
2525 | if (len < sizeof(ctd)) | |
2526 | return -EINVAL; | |
2527 | ||
2528 | memset(&ctd, 0, sizeof(ctd)); | |
2529 | ctd.tcpct_flags = (tp->rx_opt.cookie_in_always ? | |
2530 | TCP_COOKIE_IN_ALWAYS : 0) | |
2531 | | (tp->rx_opt.cookie_out_never ? | |
2532 | TCP_COOKIE_OUT_NEVER : 0); | |
2533 | ||
2534 | if (cvp != NULL) { | |
2535 | ctd.tcpct_flags |= (cvp->s_data_in ? | |
2536 | TCP_S_DATA_IN : 0) | |
2537 | | (cvp->s_data_out ? | |
2538 | TCP_S_DATA_OUT : 0); | |
2539 | ||
2540 | ctd.tcpct_cookie_desired = cvp->cookie_desired; | |
2541 | ctd.tcpct_s_data_desired = cvp->s_data_desired; | |
2542 | ||
e56fb50f WAS |
2543 | memcpy(&ctd.tcpct_value[0], &cvp->cookie_pair[0], |
2544 | cvp->cookie_pair_size); | |
2545 | ctd.tcpct_used = cvp->cookie_pair_size; | |
2546 | } | |
2547 | ||
2548 | if (put_user(sizeof(ctd), optlen)) | |
2549 | return -EFAULT; | |
2550 | if (copy_to_user(optval, &ctd, sizeof(ctd))) | |
2551 | return -EFAULT; | |
2552 | return 0; | |
2553 | } | |
1da177e4 LT |
2554 | default: |
2555 | return -ENOPROTOOPT; | |
3ff50b79 | 2556 | } |
1da177e4 LT |
2557 | |
2558 | if (put_user(len, optlen)) | |
2559 | return -EFAULT; | |
2560 | if (copy_to_user(optval, &val, len)) | |
2561 | return -EFAULT; | |
2562 | return 0; | |
2563 | } | |
2564 | ||
3fdadf7d DM |
2565 | int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, |
2566 | int __user *optlen) | |
2567 | { | |
2568 | struct inet_connection_sock *icsk = inet_csk(sk); | |
2569 | ||
2570 | if (level != SOL_TCP) | |
2571 | return icsk->icsk_af_ops->getsockopt(sk, level, optname, | |
2572 | optval, optlen); | |
2573 | return do_tcp_getsockopt(sk, level, optname, optval, optlen); | |
2574 | } | |
2575 | ||
2576 | #ifdef CONFIG_COMPAT | |
543d9cfe ACM |
2577 | int compat_tcp_getsockopt(struct sock *sk, int level, int optname, |
2578 | char __user *optval, int __user *optlen) | |
3fdadf7d | 2579 | { |
dec73ff0 ACM |
2580 | if (level != SOL_TCP) |
2581 | return inet_csk_compat_getsockopt(sk, level, optname, | |
2582 | optval, optlen); | |
3fdadf7d DM |
2583 | return do_tcp_getsockopt(sk, level, optname, optval, optlen); |
2584 | } | |
543d9cfe ACM |
2585 | |
2586 | EXPORT_SYMBOL(compat_tcp_getsockopt); | |
3fdadf7d | 2587 | #endif |
1da177e4 | 2588 | |
576a30eb | 2589 | struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int features) |
f4c50d99 HX |
2590 | { |
2591 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
2592 | struct tcphdr *th; | |
2593 | unsigned thlen; | |
2594 | unsigned int seq; | |
d3bc23e7 | 2595 | __be32 delta; |
f4c50d99 | 2596 | unsigned int oldlen; |
4e704ee3 | 2597 | unsigned int mss; |
f4c50d99 HX |
2598 | |
2599 | if (!pskb_may_pull(skb, sizeof(*th))) | |
2600 | goto out; | |
2601 | ||
aa8223c7 | 2602 | th = tcp_hdr(skb); |
f4c50d99 HX |
2603 | thlen = th->doff * 4; |
2604 | if (thlen < sizeof(*th)) | |
2605 | goto out; | |
2606 | ||
2607 | if (!pskb_may_pull(skb, thlen)) | |
2608 | goto out; | |
2609 | ||
0718bcc0 | 2610 | oldlen = (u16)~skb->len; |
f4c50d99 HX |
2611 | __skb_pull(skb, thlen); |
2612 | ||
4e704ee3 HX |
2613 | mss = skb_shinfo(skb)->gso_size; |
2614 | if (unlikely(skb->len <= mss)) | |
2615 | goto out; | |
2616 | ||
3820c3f3 HX |
2617 | if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) { |
2618 | /* Packet is from an untrusted source, reset gso_segs. */ | |
bbcf467d | 2619 | int type = skb_shinfo(skb)->gso_type; |
bbcf467d HX |
2620 | |
2621 | if (unlikely(type & | |
2622 | ~(SKB_GSO_TCPV4 | | |
2623 | SKB_GSO_DODGY | | |
2624 | SKB_GSO_TCP_ECN | | |
2625 | SKB_GSO_TCPV6 | | |
2626 | 0) || | |
2627 | !(type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))) | |
2628 | goto out; | |
3820c3f3 | 2629 | |
172589cc | 2630 | skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss); |
3820c3f3 HX |
2631 | |
2632 | segs = NULL; | |
2633 | goto out; | |
2634 | } | |
2635 | ||
576a30eb | 2636 | segs = skb_segment(skb, features); |
f4c50d99 HX |
2637 | if (IS_ERR(segs)) |
2638 | goto out; | |
2639 | ||
4e704ee3 | 2640 | delta = htonl(oldlen + (thlen + mss)); |
f4c50d99 HX |
2641 | |
2642 | skb = segs; | |
aa8223c7 | 2643 | th = tcp_hdr(skb); |
f4c50d99 HX |
2644 | seq = ntohl(th->seq); |
2645 | ||
2646 | do { | |
2647 | th->fin = th->psh = 0; | |
2648 | ||
d3bc23e7 AV |
2649 | th->check = ~csum_fold((__force __wsum)((__force u32)th->check + |
2650 | (__force u32)delta)); | |
84fa7933 | 2651 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
9c70220b ACM |
2652 | th->check = |
2653 | csum_fold(csum_partial(skb_transport_header(skb), | |
2654 | thlen, skb->csum)); | |
f4c50d99 | 2655 | |
4e704ee3 | 2656 | seq += mss; |
f4c50d99 | 2657 | skb = skb->next; |
aa8223c7 | 2658 | th = tcp_hdr(skb); |
f4c50d99 HX |
2659 | |
2660 | th->seq = htonl(seq); | |
2661 | th->cwr = 0; | |
2662 | } while (skb->next); | |
2663 | ||
27a884dc | 2664 | delta = htonl(oldlen + (skb->tail - skb->transport_header) + |
9c70220b | 2665 | skb->data_len); |
d3bc23e7 AV |
2666 | th->check = ~csum_fold((__force __wsum)((__force u32)th->check + |
2667 | (__force u32)delta)); | |
84fa7933 | 2668 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
9c70220b ACM |
2669 | th->check = csum_fold(csum_partial(skb_transport_header(skb), |
2670 | thlen, skb->csum)); | |
f4c50d99 HX |
2671 | |
2672 | out: | |
2673 | return segs; | |
2674 | } | |
adcfc7d0 | 2675 | EXPORT_SYMBOL(tcp_tso_segment); |
f4c50d99 | 2676 | |
bf296b12 HX |
2677 | struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb) |
2678 | { | |
2679 | struct sk_buff **pp = NULL; | |
2680 | struct sk_buff *p; | |
2681 | struct tcphdr *th; | |
2682 | struct tcphdr *th2; | |
a0a69a01 | 2683 | unsigned int len; |
bf296b12 HX |
2684 | unsigned int thlen; |
2685 | unsigned int flags; | |
bf296b12 | 2686 | unsigned int mss = 1; |
a5b1cf28 HX |
2687 | unsigned int hlen; |
2688 | unsigned int off; | |
bf296b12 | 2689 | int flush = 1; |
aa6320d3 | 2690 | int i; |
bf296b12 | 2691 | |
a5b1cf28 HX |
2692 | off = skb_gro_offset(skb); |
2693 | hlen = off + sizeof(*th); | |
2694 | th = skb_gro_header_fast(skb, off); | |
2695 | if (skb_gro_header_hard(skb, hlen)) { | |
2696 | th = skb_gro_header_slow(skb, hlen, off); | |
2697 | if (unlikely(!th)) | |
2698 | goto out; | |
2699 | } | |
bf296b12 | 2700 | |
bf296b12 HX |
2701 | thlen = th->doff * 4; |
2702 | if (thlen < sizeof(*th)) | |
2703 | goto out; | |
2704 | ||
a5b1cf28 HX |
2705 | hlen = off + thlen; |
2706 | if (skb_gro_header_hard(skb, hlen)) { | |
2707 | th = skb_gro_header_slow(skb, hlen, off); | |
2708 | if (unlikely(!th)) | |
2709 | goto out; | |
2710 | } | |
bf296b12 | 2711 | |
86911732 | 2712 | skb_gro_pull(skb, thlen); |
bf296b12 | 2713 | |
a0a69a01 | 2714 | len = skb_gro_len(skb); |
bf296b12 HX |
2715 | flags = tcp_flag_word(th); |
2716 | ||
2717 | for (; (p = *head); head = &p->next) { | |
2718 | if (!NAPI_GRO_CB(p)->same_flow) | |
2719 | continue; | |
2720 | ||
2721 | th2 = tcp_hdr(p); | |
2722 | ||
745898ea | 2723 | if (*(u32 *)&th->source ^ *(u32 *)&th2->source) { |
bf296b12 HX |
2724 | NAPI_GRO_CB(p)->same_flow = 0; |
2725 | continue; | |
2726 | } | |
2727 | ||
2728 | goto found; | |
2729 | } | |
2730 | ||
2731 | goto out_check_final; | |
2732 | ||
2733 | found: | |
2734 | flush = NAPI_GRO_CB(p)->flush; | |
2735 | flush |= flags & TCP_FLAG_CWR; | |
2736 | flush |= (flags ^ tcp_flag_word(th2)) & | |
2737 | ~(TCP_FLAG_CWR | TCP_FLAG_FIN | TCP_FLAG_PSH); | |
4a9a2968 | 2738 | flush |= th->ack_seq ^ th2->ack_seq; |
a2a804cd | 2739 | for (i = sizeof(*th); i < thlen; i += 4) |
aa6320d3 HX |
2740 | flush |= *(u32 *)((u8 *)th + i) ^ |
2741 | *(u32 *)((u8 *)th2 + i); | |
bf296b12 | 2742 | |
b530256d | 2743 | mss = skb_shinfo(p)->gso_size; |
bf296b12 | 2744 | |
30a3ae30 | 2745 | flush |= (len - 1) >= mss; |
aa6320d3 | 2746 | flush |= (ntohl(th2->seq) + skb_gro_len(p)) ^ ntohl(th->seq); |
bf296b12 HX |
2747 | |
2748 | if (flush || skb_gro_receive(head, skb)) { | |
2749 | mss = 1; | |
2750 | goto out_check_final; | |
2751 | } | |
2752 | ||
2753 | p = *head; | |
2754 | th2 = tcp_hdr(p); | |
2755 | tcp_flag_word(th2) |= flags & (TCP_FLAG_FIN | TCP_FLAG_PSH); | |
2756 | ||
2757 | out_check_final: | |
a0a69a01 | 2758 | flush = len < mss; |
bf296b12 HX |
2759 | flush |= flags & (TCP_FLAG_URG | TCP_FLAG_PSH | TCP_FLAG_RST | |
2760 | TCP_FLAG_SYN | TCP_FLAG_FIN); | |
2761 | ||
2762 | if (p && (!NAPI_GRO_CB(skb)->same_flow || flush)) | |
2763 | pp = head; | |
2764 | ||
2765 | out: | |
2766 | NAPI_GRO_CB(skb)->flush |= flush; | |
2767 | ||
2768 | return pp; | |
2769 | } | |
684f2176 | 2770 | EXPORT_SYMBOL(tcp_gro_receive); |
bf296b12 HX |
2771 | |
2772 | int tcp_gro_complete(struct sk_buff *skb) | |
2773 | { | |
2774 | struct tcphdr *th = tcp_hdr(skb); | |
2775 | ||
2776 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
2777 | skb->csum_offset = offsetof(struct tcphdr, check); | |
2778 | skb->ip_summed = CHECKSUM_PARTIAL; | |
2779 | ||
bf296b12 HX |
2780 | skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; |
2781 | ||
2782 | if (th->cwr) | |
2783 | skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; | |
2784 | ||
2785 | return 0; | |
2786 | } | |
684f2176 | 2787 | EXPORT_SYMBOL(tcp_gro_complete); |
bf296b12 | 2788 | |
cfb6eeb4 YH |
2789 | #ifdef CONFIG_TCP_MD5SIG |
2790 | static unsigned long tcp_md5sig_users; | |
7d720c3e | 2791 | static struct tcp_md5sig_pool * __percpu *tcp_md5sig_pool; |
cfb6eeb4 YH |
2792 | static DEFINE_SPINLOCK(tcp_md5sig_pool_lock); |
2793 | ||
7d720c3e | 2794 | static void __tcp_free_md5sig_pool(struct tcp_md5sig_pool * __percpu *pool) |
cfb6eeb4 YH |
2795 | { |
2796 | int cpu; | |
2797 | for_each_possible_cpu(cpu) { | |
2798 | struct tcp_md5sig_pool *p = *per_cpu_ptr(pool, cpu); | |
2799 | if (p) { | |
2800 | if (p->md5_desc.tfm) | |
2801 | crypto_free_hash(p->md5_desc.tfm); | |
2802 | kfree(p); | |
2803 | p = NULL; | |
2804 | } | |
2805 | } | |
2806 | free_percpu(pool); | |
2807 | } | |
2808 | ||
2809 | void tcp_free_md5sig_pool(void) | |
2810 | { | |
7d720c3e | 2811 | struct tcp_md5sig_pool * __percpu *pool = NULL; |
cfb6eeb4 | 2812 | |
2c4f6219 | 2813 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2814 | if (--tcp_md5sig_users == 0) { |
2815 | pool = tcp_md5sig_pool; | |
2816 | tcp_md5sig_pool = NULL; | |
2817 | } | |
2c4f6219 | 2818 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2819 | if (pool) |
2820 | __tcp_free_md5sig_pool(pool); | |
2821 | } | |
2822 | ||
2823 | EXPORT_SYMBOL(tcp_free_md5sig_pool); | |
2824 | ||
7d720c3e TH |
2825 | static struct tcp_md5sig_pool * __percpu * |
2826 | __tcp_alloc_md5sig_pool(struct sock *sk) | |
cfb6eeb4 YH |
2827 | { |
2828 | int cpu; | |
7d720c3e | 2829 | struct tcp_md5sig_pool * __percpu *pool; |
cfb6eeb4 YH |
2830 | |
2831 | pool = alloc_percpu(struct tcp_md5sig_pool *); | |
2832 | if (!pool) | |
2833 | return NULL; | |
2834 | ||
2835 | for_each_possible_cpu(cpu) { | |
2836 | struct tcp_md5sig_pool *p; | |
2837 | struct crypto_hash *hash; | |
2838 | ||
aa133076 | 2839 | p = kzalloc(sizeof(*p), sk->sk_allocation); |
cfb6eeb4 YH |
2840 | if (!p) |
2841 | goto out_free; | |
2842 | *per_cpu_ptr(pool, cpu) = p; | |
2843 | ||
2844 | hash = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC); | |
2845 | if (!hash || IS_ERR(hash)) | |
2846 | goto out_free; | |
2847 | ||
2848 | p->md5_desc.tfm = hash; | |
2849 | } | |
2850 | return pool; | |
2851 | out_free: | |
2852 | __tcp_free_md5sig_pool(pool); | |
2853 | return NULL; | |
2854 | } | |
2855 | ||
7d720c3e | 2856 | struct tcp_md5sig_pool * __percpu *tcp_alloc_md5sig_pool(struct sock *sk) |
cfb6eeb4 | 2857 | { |
7d720c3e | 2858 | struct tcp_md5sig_pool * __percpu *pool; |
cfb6eeb4 YH |
2859 | int alloc = 0; |
2860 | ||
2861 | retry: | |
2c4f6219 | 2862 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2863 | pool = tcp_md5sig_pool; |
2864 | if (tcp_md5sig_users++ == 0) { | |
2865 | alloc = 1; | |
2c4f6219 | 2866 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2867 | } else if (!pool) { |
2868 | tcp_md5sig_users--; | |
2c4f6219 | 2869 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2870 | cpu_relax(); |
2871 | goto retry; | |
2872 | } else | |
2c4f6219 | 2873 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2874 | |
2875 | if (alloc) { | |
2876 | /* we cannot hold spinlock here because this may sleep. */ | |
7d720c3e TH |
2877 | struct tcp_md5sig_pool * __percpu *p; |
2878 | ||
2879 | p = __tcp_alloc_md5sig_pool(sk); | |
2c4f6219 | 2880 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2881 | if (!p) { |
2882 | tcp_md5sig_users--; | |
2c4f6219 | 2883 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2884 | return NULL; |
2885 | } | |
2886 | pool = tcp_md5sig_pool; | |
2887 | if (pool) { | |
2888 | /* oops, it has already been assigned. */ | |
2c4f6219 | 2889 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2890 | __tcp_free_md5sig_pool(p); |
2891 | } else { | |
2892 | tcp_md5sig_pool = pool = p; | |
2c4f6219 | 2893 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2894 | } |
2895 | } | |
2896 | return pool; | |
2897 | } | |
2898 | ||
2899 | EXPORT_SYMBOL(tcp_alloc_md5sig_pool); | |
2900 | ||
2901 | struct tcp_md5sig_pool *__tcp_get_md5sig_pool(int cpu) | |
2902 | { | |
7d720c3e | 2903 | struct tcp_md5sig_pool * __percpu *p; |
2c4f6219 | 2904 | spin_lock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2905 | p = tcp_md5sig_pool; |
2906 | if (p) | |
2907 | tcp_md5sig_users++; | |
2c4f6219 | 2908 | spin_unlock_bh(&tcp_md5sig_pool_lock); |
cfb6eeb4 YH |
2909 | return (p ? *per_cpu_ptr(p, cpu) : NULL); |
2910 | } | |
2911 | ||
2912 | EXPORT_SYMBOL(__tcp_get_md5sig_pool); | |
2913 | ||
6931ba7c DM |
2914 | void __tcp_put_md5sig_pool(void) |
2915 | { | |
2916 | tcp_free_md5sig_pool(); | |
cfb6eeb4 YH |
2917 | } |
2918 | ||
2919 | EXPORT_SYMBOL(__tcp_put_md5sig_pool); | |
49a72dfb AL |
2920 | |
2921 | int tcp_md5_hash_header(struct tcp_md5sig_pool *hp, | |
2922 | struct tcphdr *th) | |
2923 | { | |
2924 | struct scatterlist sg; | |
2925 | int err; | |
2926 | ||
2927 | __sum16 old_checksum = th->check; | |
2928 | th->check = 0; | |
2929 | /* options aren't included in the hash */ | |
2930 | sg_init_one(&sg, th, sizeof(struct tcphdr)); | |
2931 | err = crypto_hash_update(&hp->md5_desc, &sg, sizeof(struct tcphdr)); | |
2932 | th->check = old_checksum; | |
2933 | return err; | |
2934 | } | |
2935 | ||
2936 | EXPORT_SYMBOL(tcp_md5_hash_header); | |
2937 | ||
2938 | int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp, | |
2939 | struct sk_buff *skb, unsigned header_len) | |
2940 | { | |
2941 | struct scatterlist sg; | |
2942 | const struct tcphdr *tp = tcp_hdr(skb); | |
2943 | struct hash_desc *desc = &hp->md5_desc; | |
2944 | unsigned i; | |
2945 | const unsigned head_data_len = skb_headlen(skb) > header_len ? | |
2946 | skb_headlen(skb) - header_len : 0; | |
2947 | const struct skb_shared_info *shi = skb_shinfo(skb); | |
2948 | ||
2949 | sg_init_table(&sg, 1); | |
2950 | ||
2951 | sg_set_buf(&sg, ((u8 *) tp) + header_len, head_data_len); | |
2952 | if (crypto_hash_update(desc, &sg, head_data_len)) | |
2953 | return 1; | |
2954 | ||
2955 | for (i = 0; i < shi->nr_frags; ++i) { | |
2956 | const struct skb_frag_struct *f = &shi->frags[i]; | |
2957 | sg_set_page(&sg, f->page, f->size, f->page_offset); | |
2958 | if (crypto_hash_update(desc, &sg, f->size)) | |
2959 | return 1; | |
2960 | } | |
2961 | ||
2962 | return 0; | |
2963 | } | |
2964 | ||
2965 | EXPORT_SYMBOL(tcp_md5_hash_skb_data); | |
2966 | ||
2967 | int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, struct tcp_md5sig_key *key) | |
2968 | { | |
2969 | struct scatterlist sg; | |
2970 | ||
2971 | sg_init_one(&sg, key->key, key->keylen); | |
2972 | return crypto_hash_update(&hp->md5_desc, &sg, key->keylen); | |
2973 | } | |
2974 | ||
2975 | EXPORT_SYMBOL(tcp_md5_hash_key); | |
2976 | ||
cfb6eeb4 YH |
2977 | #endif |
2978 | ||
da5c78c8 WAS |
2979 | /** |
2980 | * Each Responder maintains up to two secret values concurrently for | |
2981 | * efficient secret rollover. Each secret value has 4 states: | |
2982 | * | |
2983 | * Generating. (tcp_secret_generating != tcp_secret_primary) | |
2984 | * Generates new Responder-Cookies, but not yet used for primary | |
2985 | * verification. This is a short-term state, typically lasting only | |
2986 | * one round trip time (RTT). | |
2987 | * | |
2988 | * Primary. (tcp_secret_generating == tcp_secret_primary) | |
2989 | * Used both for generation and primary verification. | |
2990 | * | |
2991 | * Retiring. (tcp_secret_retiring != tcp_secret_secondary) | |
2992 | * Used for verification, until the first failure that can be | |
2993 | * verified by the newer Generating secret. At that time, this | |
2994 | * cookie's state is changed to Secondary, and the Generating | |
2995 | * cookie's state is changed to Primary. This is a short-term state, | |
2996 | * typically lasting only one round trip time (RTT). | |
2997 | * | |
2998 | * Secondary. (tcp_secret_retiring == tcp_secret_secondary) | |
2999 | * Used for secondary verification, after primary verification | |
3000 | * failures. This state lasts no more than twice the Maximum Segment | |
3001 | * Lifetime (2MSL). Then, the secret is discarded. | |
3002 | */ | |
3003 | struct tcp_cookie_secret { | |
3004 | /* The secret is divided into two parts. The digest part is the | |
3005 | * equivalent of previously hashing a secret and saving the state, | |
3006 | * and serves as an initialization vector (IV). The message part | |
3007 | * serves as the trailing secret. | |
3008 | */ | |
3009 | u32 secrets[COOKIE_WORKSPACE_WORDS]; | |
3010 | unsigned long expires; | |
3011 | }; | |
3012 | ||
3013 | #define TCP_SECRET_1MSL (HZ * TCP_PAWS_MSL) | |
3014 | #define TCP_SECRET_2MSL (HZ * TCP_PAWS_MSL * 2) | |
3015 | #define TCP_SECRET_LIFE (HZ * 600) | |
3016 | ||
3017 | static struct tcp_cookie_secret tcp_secret_one; | |
3018 | static struct tcp_cookie_secret tcp_secret_two; | |
3019 | ||
3020 | /* Essentially a circular list, without dynamic allocation. */ | |
3021 | static struct tcp_cookie_secret *tcp_secret_generating; | |
3022 | static struct tcp_cookie_secret *tcp_secret_primary; | |
3023 | static struct tcp_cookie_secret *tcp_secret_retiring; | |
3024 | static struct tcp_cookie_secret *tcp_secret_secondary; | |
3025 | ||
3026 | static DEFINE_SPINLOCK(tcp_secret_locker); | |
3027 | ||
3028 | /* Select a pseudo-random word in the cookie workspace. | |
3029 | */ | |
3030 | static inline u32 tcp_cookie_work(const u32 *ws, const int n) | |
3031 | { | |
3032 | return ws[COOKIE_DIGEST_WORDS + ((COOKIE_MESSAGE_WORDS-1) & ws[n])]; | |
3033 | } | |
3034 | ||
3035 | /* Fill bakery[COOKIE_WORKSPACE_WORDS] with generator, updating as needed. | |
3036 | * Called in softirq context. | |
3037 | * Returns: 0 for success. | |
3038 | */ | |
3039 | int tcp_cookie_generator(u32 *bakery) | |
3040 | { | |
3041 | unsigned long jiffy = jiffies; | |
3042 | ||
3043 | if (unlikely(time_after_eq(jiffy, tcp_secret_generating->expires))) { | |
3044 | spin_lock_bh(&tcp_secret_locker); | |
3045 | if (!time_after_eq(jiffy, tcp_secret_generating->expires)) { | |
3046 | /* refreshed by another */ | |
3047 | memcpy(bakery, | |
3048 | &tcp_secret_generating->secrets[0], | |
3049 | COOKIE_WORKSPACE_WORDS); | |
3050 | } else { | |
3051 | /* still needs refreshing */ | |
3052 | get_random_bytes(bakery, COOKIE_WORKSPACE_WORDS); | |
3053 | ||
3054 | /* The first time, paranoia assumes that the | |
3055 | * randomization function isn't as strong. But, | |
3056 | * this secret initialization is delayed until | |
3057 | * the last possible moment (packet arrival). | |
3058 | * Although that time is observable, it is | |
3059 | * unpredictably variable. Mash in the most | |
3060 | * volatile clock bits available, and expire the | |
3061 | * secret extra quickly. | |
3062 | */ | |
3063 | if (unlikely(tcp_secret_primary->expires == | |
3064 | tcp_secret_secondary->expires)) { | |
3065 | struct timespec tv; | |
3066 | ||
3067 | getnstimeofday(&tv); | |
3068 | bakery[COOKIE_DIGEST_WORDS+0] ^= | |
3069 | (u32)tv.tv_nsec; | |
3070 | ||
3071 | tcp_secret_secondary->expires = jiffy | |
3072 | + TCP_SECRET_1MSL | |
3073 | + (0x0f & tcp_cookie_work(bakery, 0)); | |
3074 | } else { | |
3075 | tcp_secret_secondary->expires = jiffy | |
3076 | + TCP_SECRET_LIFE | |
3077 | + (0xff & tcp_cookie_work(bakery, 1)); | |
3078 | tcp_secret_primary->expires = jiffy | |
3079 | + TCP_SECRET_2MSL | |
3080 | + (0x1f & tcp_cookie_work(bakery, 2)); | |
3081 | } | |
3082 | memcpy(&tcp_secret_secondary->secrets[0], | |
3083 | bakery, COOKIE_WORKSPACE_WORDS); | |
3084 | ||
3085 | rcu_assign_pointer(tcp_secret_generating, | |
3086 | tcp_secret_secondary); | |
3087 | rcu_assign_pointer(tcp_secret_retiring, | |
3088 | tcp_secret_primary); | |
3089 | /* | |
3090 | * Neither call_rcu() nor synchronize_rcu() needed. | |
3091 | * Retiring data is not freed. It is replaced after | |
3092 | * further (locked) pointer updates, and a quiet time | |
3093 | * (minimum 1MSL, maximum LIFE - 2MSL). | |
3094 | */ | |
3095 | } | |
3096 | spin_unlock_bh(&tcp_secret_locker); | |
3097 | } else { | |
3098 | rcu_read_lock_bh(); | |
3099 | memcpy(bakery, | |
3100 | &rcu_dereference(tcp_secret_generating)->secrets[0], | |
3101 | COOKIE_WORKSPACE_WORDS); | |
3102 | rcu_read_unlock_bh(); | |
3103 | } | |
3104 | return 0; | |
3105 | } | |
3106 | EXPORT_SYMBOL(tcp_cookie_generator); | |
3107 | ||
4ac02bab AK |
3108 | void tcp_done(struct sock *sk) |
3109 | { | |
5a5f3a8d | 3110 | if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV) |
63231bdd | 3111 | TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_ATTEMPTFAILS); |
4ac02bab AK |
3112 | |
3113 | tcp_set_state(sk, TCP_CLOSE); | |
3114 | tcp_clear_xmit_timers(sk); | |
3115 | ||
3116 | sk->sk_shutdown = SHUTDOWN_MASK; | |
3117 | ||
3118 | if (!sock_flag(sk, SOCK_DEAD)) | |
3119 | sk->sk_state_change(sk); | |
3120 | else | |
3121 | inet_csk_destroy_sock(sk); | |
3122 | } | |
3123 | EXPORT_SYMBOL_GPL(tcp_done); | |
3124 | ||
5f8ef48d | 3125 | extern struct tcp_congestion_ops tcp_reno; |
1da177e4 LT |
3126 | |
3127 | static __initdata unsigned long thash_entries; | |
3128 | static int __init set_thash_entries(char *str) | |
3129 | { | |
3130 | if (!str) | |
3131 | return 0; | |
3132 | thash_entries = simple_strtoul(str, &str, 0); | |
3133 | return 1; | |
3134 | } | |
3135 | __setup("thash_entries=", set_thash_entries); | |
3136 | ||
3137 | void __init tcp_init(void) | |
3138 | { | |
3139 | struct sk_buff *skb = NULL; | |
57413ebc | 3140 | unsigned long nr_pages, limit; |
7b4f4b5e | 3141 | int order, i, max_share; |
da5c78c8 | 3142 | unsigned long jiffy = jiffies; |
1da177e4 | 3143 | |
1f9e636e | 3144 | BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof(skb->cb)); |
1da177e4 | 3145 | |
1748376b | 3146 | percpu_counter_init(&tcp_sockets_allocated, 0); |
dd24c001 | 3147 | percpu_counter_init(&tcp_orphan_count, 0); |
6e04e021 ACM |
3148 | tcp_hashinfo.bind_bucket_cachep = |
3149 | kmem_cache_create("tcp_bind_bucket", | |
3150 | sizeof(struct inet_bind_bucket), 0, | |
20c2df83 | 3151 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 3152 | |
1da177e4 LT |
3153 | /* Size and allocate the main established and bind bucket |
3154 | * hash tables. | |
3155 | * | |
3156 | * The methodology is similar to that of the buffer cache. | |
3157 | */ | |
6e04e021 | 3158 | tcp_hashinfo.ehash = |
1da177e4 | 3159 | alloc_large_system_hash("TCP established", |
0f7ff927 | 3160 | sizeof(struct inet_ehash_bucket), |
1da177e4 | 3161 | thash_entries, |
4481374c | 3162 | (totalram_pages >= 128 * 1024) ? |
18955cfc | 3163 | 13 : 15, |
9e950efa | 3164 | 0, |
1da177e4 | 3165 | NULL, |
f373b53b | 3166 | &tcp_hashinfo.ehash_mask, |
0ccfe618 | 3167 | thash_entries ? 0 : 512 * 1024); |
f373b53b | 3168 | for (i = 0; i <= tcp_hashinfo.ehash_mask; i++) { |
3ab5aee7 ED |
3169 | INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].chain, i); |
3170 | INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].twchain, i); | |
1da177e4 | 3171 | } |
230140cf ED |
3172 | if (inet_ehash_locks_alloc(&tcp_hashinfo)) |
3173 | panic("TCP: failed to alloc ehash_locks"); | |
6e04e021 | 3174 | tcp_hashinfo.bhash = |
1da177e4 | 3175 | alloc_large_system_hash("TCP bind", |
0f7ff927 | 3176 | sizeof(struct inet_bind_hashbucket), |
f373b53b | 3177 | tcp_hashinfo.ehash_mask + 1, |
4481374c | 3178 | (totalram_pages >= 128 * 1024) ? |
18955cfc | 3179 | 13 : 15, |
9e950efa | 3180 | 0, |
6e04e021 | 3181 | &tcp_hashinfo.bhash_size, |
1da177e4 LT |
3182 | NULL, |
3183 | 64 * 1024); | |
6e04e021 ACM |
3184 | tcp_hashinfo.bhash_size = 1 << tcp_hashinfo.bhash_size; |
3185 | for (i = 0; i < tcp_hashinfo.bhash_size; i++) { | |
3186 | spin_lock_init(&tcp_hashinfo.bhash[i].lock); | |
3187 | INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain); | |
1da177e4 LT |
3188 | } |
3189 | ||
3190 | /* Try to be a bit smarter and adjust defaults depending | |
3191 | * on available memory. | |
3192 | */ | |
3193 | for (order = 0; ((1 << order) << PAGE_SHIFT) < | |
6e04e021 | 3194 | (tcp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket)); |
1da177e4 LT |
3195 | order++) |
3196 | ; | |
e7626486 | 3197 | if (order >= 4) { |
295ff7ed | 3198 | tcp_death_row.sysctl_max_tw_buckets = 180000; |
1da177e4 LT |
3199 | sysctl_tcp_max_orphans = 4096 << (order - 4); |
3200 | sysctl_max_syn_backlog = 1024; | |
3201 | } else if (order < 3) { | |
295ff7ed | 3202 | tcp_death_row.sysctl_max_tw_buckets >>= (3 - order); |
1da177e4 LT |
3203 | sysctl_tcp_max_orphans >>= (3 - order); |
3204 | sysctl_max_syn_backlog = 128; | |
3205 | } | |
1da177e4 | 3206 | |
53cdcc04 JH |
3207 | /* Set the pressure threshold to be a fraction of global memory that |
3208 | * is up to 1/2 at 256 MB, decreasing toward zero with the amount of | |
3209 | * memory, with a floor of 128 pages. | |
3210 | */ | |
57413ebc MS |
3211 | nr_pages = totalram_pages - totalhigh_pages; |
3212 | limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT); | |
3213 | limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11); | |
53cdcc04 JH |
3214 | limit = max(limit, 128UL); |
3215 | sysctl_tcp_mem[0] = limit / 4 * 3; | |
3216 | sysctl_tcp_mem[1] = limit; | |
52bf376c | 3217 | sysctl_tcp_mem[2] = sysctl_tcp_mem[0] * 2; |
1da177e4 | 3218 | |
53cdcc04 | 3219 | /* Set per-socket limits to no more than 1/128 the pressure threshold */ |
7b4f4b5e JH |
3220 | limit = ((unsigned long)sysctl_tcp_mem[1]) << (PAGE_SHIFT - 7); |
3221 | max_share = min(4UL*1024*1024, limit); | |
3222 | ||
3ab224be | 3223 | sysctl_tcp_wmem[0] = SK_MEM_QUANTUM; |
7b4f4b5e JH |
3224 | sysctl_tcp_wmem[1] = 16*1024; |
3225 | sysctl_tcp_wmem[2] = max(64*1024, max_share); | |
3226 | ||
3ab224be | 3227 | sysctl_tcp_rmem[0] = SK_MEM_QUANTUM; |
7b4f4b5e JH |
3228 | sysctl_tcp_rmem[1] = 87380; |
3229 | sysctl_tcp_rmem[2] = max(87380, max_share); | |
1da177e4 LT |
3230 | |
3231 | printk(KERN_INFO "TCP: Hash tables configured " | |
f373b53b ED |
3232 | "(established %u bind %u)\n", |
3233 | tcp_hashinfo.ehash_mask + 1, tcp_hashinfo.bhash_size); | |
317a76f9 SH |
3234 | |
3235 | tcp_register_congestion_control(&tcp_reno); | |
da5c78c8 WAS |
3236 | |
3237 | memset(&tcp_secret_one.secrets[0], 0, sizeof(tcp_secret_one.secrets)); | |
3238 | memset(&tcp_secret_two.secrets[0], 0, sizeof(tcp_secret_two.secrets)); | |
3239 | tcp_secret_one.expires = jiffy; /* past due */ | |
3240 | tcp_secret_two.expires = jiffy; /* past due */ | |
3241 | tcp_secret_generating = &tcp_secret_one; | |
3242 | tcp_secret_primary = &tcp_secret_one; | |
3243 | tcp_secret_retiring = &tcp_secret_two; | |
3244 | tcp_secret_secondary = &tcp_secret_two; | |
1da177e4 LT |
3245 | } |
3246 | ||
1da177e4 | 3247 | EXPORT_SYMBOL(tcp_close); |
1da177e4 LT |
3248 | EXPORT_SYMBOL(tcp_disconnect); |
3249 | EXPORT_SYMBOL(tcp_getsockopt); | |
3250 | EXPORT_SYMBOL(tcp_ioctl); | |
1da177e4 LT |
3251 | EXPORT_SYMBOL(tcp_poll); |
3252 | EXPORT_SYMBOL(tcp_read_sock); | |
3253 | EXPORT_SYMBOL(tcp_recvmsg); | |
3254 | EXPORT_SYMBOL(tcp_sendmsg); | |
9c55e01c | 3255 | EXPORT_SYMBOL(tcp_splice_read); |
1da177e4 LT |
3256 | EXPORT_SYMBOL(tcp_sendpage); |
3257 | EXPORT_SYMBOL(tcp_setsockopt); | |
3258 | EXPORT_SYMBOL(tcp_shutdown); |