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 * PF_INET protocol family socket handler.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Florian La Roche, <flla@stud.uni-sb.de>
11 * Alan Cox, <A.Cox@swansea.ac.uk>
12 *
13 * Changes (see also sock.c)
14 *
15 * piggy,
16 * Karl Knutson : Socket protocol table
17 * A.N.Kuznetsov : Socket death error in accept().
18 * John Richardson : Fix non blocking error in connect()
19 * so sockets that fail to connect
20 * don't return -EINPROGRESS.
21 * Alan Cox : Asynchronous I/O support
22 * Alan Cox : Keep correct socket pointer on sock
23 * structures
24 * when accept() ed
25 * Alan Cox : Semantics of SO_LINGER aren't state
26 * moved to close when you look carefully.
27 * With this fixed and the accept bug fixed
28 * some RPC stuff seems happier.
29 * Niibe Yutaka : 4.4BSD style write async I/O
30 * Alan Cox,
31 * Tony Gale : Fixed reuse semantics.
32 * Alan Cox : bind() shouldn't abort existing but dead
33 * sockets. Stops FTP netin:.. I hope.
34 * Alan Cox : bind() works correctly for RAW sockets.
35 * Note that FreeBSD at least was broken
36 * in this respect so be careful with
37 * compatibility tests...
38 * Alan Cox : routing cache support
39 * Alan Cox : memzero the socket structure for
40 * compactness.
41 * Matt Day : nonblock connect error handler
42 * Alan Cox : Allow large numbers of pending sockets
43 * (eg for big web sites), but only if
44 * specifically application requested.
45 * Alan Cox : New buffering throughout IP. Used
46 * dumbly.
47 * Alan Cox : New buffering now used smartly.
48 * Alan Cox : BSD rather than common sense
49 * interpretation of listen.
50 * Germano Caronni : Assorted small races.
51 * Alan Cox : sendmsg/recvmsg basic support.
52 * Alan Cox : Only sendmsg/recvmsg now supported.
53 * Alan Cox : Locked down bind (see security list).
54 * Alan Cox : Loosened bind a little.
55 * Mike McLagan : ADD/DEL DLCI Ioctls
56 * Willy Konynenberg : Transparent proxying support.
57 * David S. Miller : New socket lookup architecture.
58 * Some other random speedups.
59 * Cyrus Durgin : Cleaned up file for kmod hacks.
60 * Andi Kleen : Fix inet_stream_connect TCP race.
61 *
62 * This program is free software; you can redistribute it and/or
63 * modify it under the terms of the GNU General Public License
64 * as published by the Free Software Foundation; either version
65 * 2 of the License, or (at your option) any later version.
66 */
67
68 #define pr_fmt(fmt) "IPv4: " fmt
69
70 #include <linux/err.h>
71 #include <linux/errno.h>
72 #include <linux/types.h>
73 #include <linux/socket.h>
74 #include <linux/in.h>
75 #include <linux/kernel.h>
76 #include <linux/module.h>
77 #include <linux/sched.h>
78 #include <linux/timer.h>
79 #include <linux/string.h>
80 #include <linux/sockios.h>
81 #include <linux/net.h>
82 #include <linux/capability.h>
83 #include <linux/fcntl.h>
84 #include <linux/mm.h>
85 #include <linux/interrupt.h>
86 #include <linux/stat.h>
87 #include <linux/init.h>
88 #include <linux/poll.h>
89 #include <linux/netfilter_ipv4.h>
90 #include <linux/random.h>
91 #include <linux/slab.h>
92
93 #include <asm/uaccess.h>
94
95 #include <linux/inet.h>
96 #include <linux/igmp.h>
97 #include <linux/inetdevice.h>
98 #include <linux/netdevice.h>
99 #include <net/checksum.h>
100 #include <net/ip.h>
101 #include <net/protocol.h>
102 #include <net/arp.h>
103 #include <net/route.h>
104 #include <net/ip_fib.h>
105 #include <net/inet_connection_sock.h>
106 #include <net/tcp.h>
107 #include <net/udp.h>
108 #include <net/udplite.h>
109 #include <net/ping.h>
110 #include <linux/skbuff.h>
111 #include <net/sock.h>
112 #include <net/raw.h>
113 #include <net/icmp.h>
114 #include <net/ipip.h>
115 #include <net/inet_common.h>
116 #include <net/xfrm.h>
117 #include <net/net_namespace.h>
118 #ifdef CONFIG_IP_MROUTE
119 #include <linux/mroute.h>
120 #endif
121
122
123 /* The inetsw table contains everything that inet_create needs to
124 * build a new socket.
125 */
126 static struct list_head inetsw[SOCK_MAX];
127 static DEFINE_SPINLOCK(inetsw_lock);
128
129 struct ipv4_config ipv4_config;
130 EXPORT_SYMBOL(ipv4_config);
131
132 /* New destruction routine */
133
inet_sock_destruct(struct sock * sk)134 void inet_sock_destruct(struct sock *sk)
135 {
136 struct inet_sock *inet = inet_sk(sk);
137
138 __skb_queue_purge(&sk->sk_receive_queue);
139 __skb_queue_purge(&sk->sk_error_queue);
140
141 sk_mem_reclaim(sk);
142
143 if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
144 pr_err("Attempt to release TCP socket in state %d %p\n",
145 sk->sk_state, sk);
146 return;
147 }
148 if (!sock_flag(sk, SOCK_DEAD)) {
149 pr_err("Attempt to release alive inet socket %p\n", sk);
150 return;
151 }
152
153 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
154 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
155 WARN_ON(sk->sk_wmem_queued);
156 WARN_ON(sk->sk_forward_alloc);
157
158 kfree(rcu_dereference_protected(inet->inet_opt, 1));
159 dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
160 sk_refcnt_debug_dec(sk);
161 }
162 EXPORT_SYMBOL(inet_sock_destruct);
163
164 /*
165 * The routines beyond this point handle the behaviour of an AF_INET
166 * socket object. Mostly it punts to the subprotocols of IP to do
167 * the work.
168 */
169
170 /*
171 * Automatically bind an unbound socket.
172 */
173
inet_autobind(struct sock * sk)174 static int inet_autobind(struct sock *sk)
175 {
176 struct inet_sock *inet;
177 /* We may need to bind the socket. */
178 lock_sock(sk);
179 inet = inet_sk(sk);
180 if (!inet->inet_num) {
181 if (sk->sk_prot->get_port(sk, 0)) {
182 release_sock(sk);
183 return -EAGAIN;
184 }
185 inet->inet_sport = htons(inet->inet_num);
186 }
187 release_sock(sk);
188 return 0;
189 }
190
191 /*
192 * Move a socket into listening state.
193 */
inet_listen(struct socket * sock,int backlog)194 int inet_listen(struct socket *sock, int backlog)
195 {
196 struct sock *sk = sock->sk;
197 unsigned char old_state;
198 int err;
199
200 lock_sock(sk);
201
202 err = -EINVAL;
203 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
204 goto out;
205
206 old_state = sk->sk_state;
207 if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
208 goto out;
209
210 /* Really, if the socket is already in listen state
211 * we can only allow the backlog to be adjusted.
212 */
213 if (old_state != TCP_LISTEN) {
214 err = inet_csk_listen_start(sk, backlog);
215 if (err)
216 goto out;
217 }
218 sk->sk_max_ack_backlog = backlog;
219 err = 0;
220
221 out:
222 release_sock(sk);
223 return err;
224 }
225 EXPORT_SYMBOL(inet_listen);
226
227 u32 inet_ehash_secret __read_mostly;
228 EXPORT_SYMBOL(inet_ehash_secret);
229
230 u32 ipv6_hash_secret __read_mostly;
231 EXPORT_SYMBOL(ipv6_hash_secret);
232
233 /*
234 * inet_ehash_secret must be set exactly once, and to a non nul value
235 * ipv6_hash_secret must be set exactly once.
236 */
build_ehash_secret(void)237 void build_ehash_secret(void)
238 {
239 u32 rnd;
240
241 do {
242 get_random_bytes(&rnd, sizeof(rnd));
243 } while (rnd == 0);
244
245 if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0)
246 get_random_bytes(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
247 }
248 EXPORT_SYMBOL(build_ehash_secret);
249
inet_netns_ok(struct net * net,int protocol)250 static inline int inet_netns_ok(struct net *net, int protocol)
251 {
252 int hash;
253 const struct net_protocol *ipprot;
254
255 if (net_eq(net, &init_net))
256 return 1;
257
258 hash = protocol & (MAX_INET_PROTOS - 1);
259 ipprot = rcu_dereference(inet_protos[hash]);
260
261 if (ipprot == NULL)
262 /* raw IP is OK */
263 return 1;
264 return ipprot->netns_ok;
265 }
266
267 /*
268 * Create an inet socket.
269 */
270
inet_create(struct net * net,struct socket * sock,int protocol,int kern)271 static int inet_create(struct net *net, struct socket *sock, int protocol,
272 int kern)
273 {
274 struct sock *sk;
275 struct inet_protosw *answer;
276 struct inet_sock *inet;
277 struct proto *answer_prot;
278 unsigned char answer_flags;
279 char answer_no_check;
280 int try_loading_module = 0;
281 int err;
282
283 if (unlikely(!inet_ehash_secret))
284 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
285 build_ehash_secret();
286
287 sock->state = SS_UNCONNECTED;
288
289 /* Look for the requested type/protocol pair. */
290 lookup_protocol:
291 err = -ESOCKTNOSUPPORT;
292 rcu_read_lock();
293 list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
294
295 err = 0;
296 /* Check the non-wild match. */
297 if (protocol == answer->protocol) {
298 if (protocol != IPPROTO_IP)
299 break;
300 } else {
301 /* Check for the two wild cases. */
302 if (IPPROTO_IP == protocol) {
303 protocol = answer->protocol;
304 break;
305 }
306 if (IPPROTO_IP == answer->protocol)
307 break;
308 }
309 err = -EPROTONOSUPPORT;
310 }
311
312 if (unlikely(err)) {
313 if (try_loading_module < 2) {
314 rcu_read_unlock();
315 /*
316 * Be more specific, e.g. net-pf-2-proto-132-type-1
317 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
318 */
319 if (++try_loading_module == 1)
320 request_module("net-pf-%d-proto-%d-type-%d",
321 PF_INET, protocol, sock->type);
322 /*
323 * Fall back to generic, e.g. net-pf-2-proto-132
324 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
325 */
326 else
327 request_module("net-pf-%d-proto-%d",
328 PF_INET, protocol);
329 goto lookup_protocol;
330 } else
331 goto out_rcu_unlock;
332 }
333
334 err = -EPERM;
335 if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
336 goto out_rcu_unlock;
337
338 err = -EAFNOSUPPORT;
339 if (!inet_netns_ok(net, protocol))
340 goto out_rcu_unlock;
341
342 sock->ops = answer->ops;
343 answer_prot = answer->prot;
344 answer_no_check = answer->no_check;
345 answer_flags = answer->flags;
346 rcu_read_unlock();
347
348 WARN_ON(answer_prot->slab == NULL);
349
350 err = -ENOBUFS;
351 sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
352 if (sk == NULL)
353 goto out;
354
355 err = 0;
356 sk->sk_no_check = answer_no_check;
357 if (INET_PROTOSW_REUSE & answer_flags)
358 sk->sk_reuse = 1;
359
360 inet = inet_sk(sk);
361 inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
362
363 inet->nodefrag = 0;
364
365 if (SOCK_RAW == sock->type) {
366 inet->inet_num = protocol;
367 if (IPPROTO_RAW == protocol)
368 inet->hdrincl = 1;
369 }
370
371 if (ipv4_config.no_pmtu_disc)
372 inet->pmtudisc = IP_PMTUDISC_DONT;
373 else
374 inet->pmtudisc = IP_PMTUDISC_WANT;
375
376 inet->inet_id = 0;
377
378 sock_init_data(sock, sk);
379
380 sk->sk_destruct = inet_sock_destruct;
381 sk->sk_protocol = protocol;
382 sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
383
384 inet->uc_ttl = -1;
385 inet->mc_loop = 1;
386 inet->mc_ttl = 1;
387 inet->mc_all = 1;
388 inet->mc_index = 0;
389 inet->mc_list = NULL;
390 inet->rcv_tos = 0;
391
392 sk_refcnt_debug_inc(sk);
393
394 if (inet->inet_num) {
395 /* It assumes that any protocol which allows
396 * the user to assign a number at socket
397 * creation time automatically
398 * shares.
399 */
400 inet->inet_sport = htons(inet->inet_num);
401 /* Add to protocol hash chains. */
402 sk->sk_prot->hash(sk);
403 }
404
405 if (sk->sk_prot->init) {
406 err = sk->sk_prot->init(sk);
407 if (err)
408 sk_common_release(sk);
409 }
410 out:
411 return err;
412 out_rcu_unlock:
413 rcu_read_unlock();
414 goto out;
415 }
416
417
418 /*
419 * The peer socket should always be NULL (or else). When we call this
420 * function we are destroying the object and from then on nobody
421 * should refer to it.
422 */
inet_release(struct socket * sock)423 int inet_release(struct socket *sock)
424 {
425 struct sock *sk = sock->sk;
426
427 if (sk) {
428 long timeout;
429
430 sock_rps_reset_flow(sk);
431
432 /* Applications forget to leave groups before exiting */
433 ip_mc_drop_socket(sk);
434
435 /* If linger is set, we don't return until the close
436 * is complete. Otherwise we return immediately. The
437 * actually closing is done the same either way.
438 *
439 * If the close is due to the process exiting, we never
440 * linger..
441 */
442 timeout = 0;
443 if (sock_flag(sk, SOCK_LINGER) &&
444 !(current->flags & PF_EXITING))
445 timeout = sk->sk_lingertime;
446 sock->sk = NULL;
447 sk->sk_prot->close(sk, timeout);
448 }
449 return 0;
450 }
451 EXPORT_SYMBOL(inet_release);
452
453 /* It is off by default, see below. */
454 int sysctl_ip_nonlocal_bind __read_mostly;
455 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
456
inet_bind(struct socket * sock,struct sockaddr * uaddr,int addr_len)457 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
458 {
459 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
460 struct sock *sk = sock->sk;
461 struct inet_sock *inet = inet_sk(sk);
462 unsigned short snum;
463 int chk_addr_ret;
464 int err;
465
466 /* If the socket has its own bind function then use it. (RAW) */
467 if (sk->sk_prot->bind) {
468 err = sk->sk_prot->bind(sk, uaddr, addr_len);
469 goto out;
470 }
471 err = -EINVAL;
472 if (addr_len < sizeof(struct sockaddr_in))
473 goto out;
474
475 if (addr->sin_family != AF_INET) {
476 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
477 * only if s_addr is INADDR_ANY.
478 */
479 err = -EAFNOSUPPORT;
480 if (addr->sin_family != AF_UNSPEC ||
481 addr->sin_addr.s_addr != htonl(INADDR_ANY))
482 goto out;
483 }
484
485 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
486
487 /* Not specified by any standard per-se, however it breaks too
488 * many applications when removed. It is unfortunate since
489 * allowing applications to make a non-local bind solves
490 * several problems with systems using dynamic addressing.
491 * (ie. your servers still start up even if your ISDN link
492 * is temporarily down)
493 */
494 err = -EADDRNOTAVAIL;
495 if (!sysctl_ip_nonlocal_bind &&
496 !(inet->freebind || inet->transparent) &&
497 addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
498 chk_addr_ret != RTN_LOCAL &&
499 chk_addr_ret != RTN_MULTICAST &&
500 chk_addr_ret != RTN_BROADCAST)
501 goto out;
502
503 snum = ntohs(addr->sin_port);
504 err = -EACCES;
505 if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
506 goto out;
507
508 /* We keep a pair of addresses. rcv_saddr is the one
509 * used by hash lookups, and saddr is used for transmit.
510 *
511 * In the BSD API these are the same except where it
512 * would be illegal to use them (multicast/broadcast) in
513 * which case the sending device address is used.
514 */
515 lock_sock(sk);
516
517 /* Check these errors (active socket, double bind). */
518 err = -EINVAL;
519 if (sk->sk_state != TCP_CLOSE || inet->inet_num)
520 goto out_release_sock;
521
522 inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
523 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
524 inet->inet_saddr = 0; /* Use device */
525
526 /* Make sure we are allowed to bind here. */
527 if (sk->sk_prot->get_port(sk, snum)) {
528 inet->inet_saddr = inet->inet_rcv_saddr = 0;
529 err = -EADDRINUSE;
530 goto out_release_sock;
531 }
532
533 if (inet->inet_rcv_saddr)
534 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
535 if (snum)
536 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
537 inet->inet_sport = htons(inet->inet_num);
538 inet->inet_daddr = 0;
539 inet->inet_dport = 0;
540 sk_dst_reset(sk);
541 err = 0;
542 out_release_sock:
543 release_sock(sk);
544 out:
545 return err;
546 }
547 EXPORT_SYMBOL(inet_bind);
548
inet_dgram_connect(struct socket * sock,struct sockaddr * uaddr,int addr_len,int flags)549 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
550 int addr_len, int flags)
551 {
552 struct sock *sk = sock->sk;
553
554 if (addr_len < sizeof(uaddr->sa_family))
555 return -EINVAL;
556 if (uaddr->sa_family == AF_UNSPEC)
557 return sk->sk_prot->disconnect(sk, flags);
558
559 if (!inet_sk(sk)->inet_num && inet_autobind(sk))
560 return -EAGAIN;
561 return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
562 }
563 EXPORT_SYMBOL(inet_dgram_connect);
564
inet_wait_for_connect(struct sock * sk,long timeo)565 static long inet_wait_for_connect(struct sock *sk, long timeo)
566 {
567 DEFINE_WAIT(wait);
568
569 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
570
571 /* Basic assumption: if someone sets sk->sk_err, he _must_
572 * change state of the socket from TCP_SYN_*.
573 * Connect() does not allow to get error notifications
574 * without closing the socket.
575 */
576 while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
577 release_sock(sk);
578 timeo = schedule_timeout(timeo);
579 lock_sock(sk);
580 if (signal_pending(current) || !timeo)
581 break;
582 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
583 }
584 finish_wait(sk_sleep(sk), &wait);
585 return timeo;
586 }
587
588 /*
589 * Connect to a remote host. There is regrettably still a little
590 * TCP 'magic' in here.
591 */
inet_stream_connect(struct socket * sock,struct sockaddr * uaddr,int addr_len,int flags)592 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
593 int addr_len, int flags)
594 {
595 struct sock *sk = sock->sk;
596 int err;
597 long timeo;
598
599 if (addr_len < sizeof(uaddr->sa_family))
600 return -EINVAL;
601
602 lock_sock(sk);
603
604 if (uaddr->sa_family == AF_UNSPEC) {
605 err = sk->sk_prot->disconnect(sk, flags);
606 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
607 goto out;
608 }
609
610 switch (sock->state) {
611 default:
612 err = -EINVAL;
613 goto out;
614 case SS_CONNECTED:
615 err = -EISCONN;
616 goto out;
617 case SS_CONNECTING:
618 err = -EALREADY;
619 /* Fall out of switch with err, set for this state */
620 break;
621 case SS_UNCONNECTED:
622 err = -EISCONN;
623 if (sk->sk_state != TCP_CLOSE)
624 goto out;
625
626 err = sk->sk_prot->connect(sk, uaddr, addr_len);
627 if (err < 0)
628 goto out;
629
630 sock->state = SS_CONNECTING;
631
632 /* Just entered SS_CONNECTING state; the only
633 * difference is that return value in non-blocking
634 * case is EINPROGRESS, rather than EALREADY.
635 */
636 err = -EINPROGRESS;
637 break;
638 }
639
640 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
641
642 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
643 /* Error code is set above */
644 if (!timeo || !inet_wait_for_connect(sk, timeo))
645 goto out;
646
647 err = sock_intr_errno(timeo);
648 if (signal_pending(current))
649 goto out;
650 }
651
652 /* Connection was closed by RST, timeout, ICMP error
653 * or another process disconnected us.
654 */
655 if (sk->sk_state == TCP_CLOSE)
656 goto sock_error;
657
658 /* sk->sk_err may be not zero now, if RECVERR was ordered by user
659 * and error was received after socket entered established state.
660 * Hence, it is handled normally after connect() return successfully.
661 */
662
663 sock->state = SS_CONNECTED;
664 err = 0;
665 out:
666 release_sock(sk);
667 return err;
668
669 sock_error:
670 err = sock_error(sk) ? : -ECONNABORTED;
671 sock->state = SS_UNCONNECTED;
672 if (sk->sk_prot->disconnect(sk, flags))
673 sock->state = SS_DISCONNECTING;
674 goto out;
675 }
676 EXPORT_SYMBOL(inet_stream_connect);
677
678 /*
679 * Accept a pending connection. The TCP layer now gives BSD semantics.
680 */
681
inet_accept(struct socket * sock,struct socket * newsock,int flags)682 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
683 {
684 struct sock *sk1 = sock->sk;
685 int err = -EINVAL;
686 struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
687
688 if (!sk2)
689 goto do_err;
690
691 lock_sock(sk2);
692
693 sock_rps_record_flow(sk2);
694 WARN_ON(!((1 << sk2->sk_state) &
695 (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
696
697 sock_graft(sk2, newsock);
698
699 newsock->state = SS_CONNECTED;
700 err = 0;
701 release_sock(sk2);
702 do_err:
703 return err;
704 }
705 EXPORT_SYMBOL(inet_accept);
706
707
708 /*
709 * This does both peername and sockname.
710 */
inet_getname(struct socket * sock,struct sockaddr * uaddr,int * uaddr_len,int peer)711 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
712 int *uaddr_len, int peer)
713 {
714 struct sock *sk = sock->sk;
715 struct inet_sock *inet = inet_sk(sk);
716 DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
717
718 sin->sin_family = AF_INET;
719 if (peer) {
720 if (!inet->inet_dport ||
721 (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
722 peer == 1))
723 return -ENOTCONN;
724 sin->sin_port = inet->inet_dport;
725 sin->sin_addr.s_addr = inet->inet_daddr;
726 } else {
727 __be32 addr = inet->inet_rcv_saddr;
728 if (!addr)
729 addr = inet->inet_saddr;
730 sin->sin_port = inet->inet_sport;
731 sin->sin_addr.s_addr = addr;
732 }
733 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
734 *uaddr_len = sizeof(*sin);
735 return 0;
736 }
737 EXPORT_SYMBOL(inet_getname);
738
inet_sendmsg(struct kiocb * iocb,struct socket * sock,struct msghdr * msg,size_t size)739 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
740 size_t size)
741 {
742 struct sock *sk = sock->sk;
743
744 sock_rps_record_flow(sk);
745
746 /* We may need to bind the socket. */
747 if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
748 inet_autobind(sk))
749 return -EAGAIN;
750
751 return sk->sk_prot->sendmsg(iocb, sk, msg, size);
752 }
753 EXPORT_SYMBOL(inet_sendmsg);
754
inet_sendpage(struct socket * sock,struct page * page,int offset,size_t size,int flags)755 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
756 size_t size, int flags)
757 {
758 struct sock *sk = sock->sk;
759
760 sock_rps_record_flow(sk);
761
762 /* We may need to bind the socket. */
763 if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
764 inet_autobind(sk))
765 return -EAGAIN;
766
767 if (sk->sk_prot->sendpage)
768 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
769 return sock_no_sendpage(sock, page, offset, size, flags);
770 }
771 EXPORT_SYMBOL(inet_sendpage);
772
inet_recvmsg(struct kiocb * iocb,struct socket * sock,struct msghdr * msg,size_t size,int flags)773 int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
774 size_t size, int flags)
775 {
776 struct sock *sk = sock->sk;
777 int addr_len = 0;
778 int err;
779
780 sock_rps_record_flow(sk);
781
782 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
783 flags & ~MSG_DONTWAIT, &addr_len);
784 if (err >= 0)
785 msg->msg_namelen = addr_len;
786 return err;
787 }
788 EXPORT_SYMBOL(inet_recvmsg);
789
inet_shutdown(struct socket * sock,int how)790 int inet_shutdown(struct socket *sock, int how)
791 {
792 struct sock *sk = sock->sk;
793 int err = 0;
794
795 /* This should really check to make sure
796 * the socket is a TCP socket. (WHY AC...)
797 */
798 how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
799 1->2 bit 2 snds.
800 2->3 */
801 if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */
802 return -EINVAL;
803
804 lock_sock(sk);
805 if (sock->state == SS_CONNECTING) {
806 if ((1 << sk->sk_state) &
807 (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
808 sock->state = SS_DISCONNECTING;
809 else
810 sock->state = SS_CONNECTED;
811 }
812
813 switch (sk->sk_state) {
814 case TCP_CLOSE:
815 err = -ENOTCONN;
816 /* Hack to wake up other listeners, who can poll for
817 POLLHUP, even on eg. unconnected UDP sockets -- RR */
818 default:
819 sk->sk_shutdown |= how;
820 if (sk->sk_prot->shutdown)
821 sk->sk_prot->shutdown(sk, how);
822 break;
823
824 /* Remaining two branches are temporary solution for missing
825 * close() in multithreaded environment. It is _not_ a good idea,
826 * but we have no choice until close() is repaired at VFS level.
827 */
828 case TCP_LISTEN:
829 if (!(how & RCV_SHUTDOWN))
830 break;
831 /* Fall through */
832 case TCP_SYN_SENT:
833 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
834 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
835 break;
836 }
837
838 /* Wake up anyone sleeping in poll. */
839 sk->sk_state_change(sk);
840 release_sock(sk);
841 return err;
842 }
843 EXPORT_SYMBOL(inet_shutdown);
844
845 /*
846 * ioctl() calls you can issue on an INET socket. Most of these are
847 * device configuration and stuff and very rarely used. Some ioctls
848 * pass on to the socket itself.
849 *
850 * NOTE: I like the idea of a module for the config stuff. ie ifconfig
851 * loads the devconfigure module does its configuring and unloads it.
852 * There's a good 20K of config code hanging around the kernel.
853 */
854
inet_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)855 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
856 {
857 struct sock *sk = sock->sk;
858 int err = 0;
859 struct net *net = sock_net(sk);
860
861 switch (cmd) {
862 case SIOCGSTAMP:
863 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
864 break;
865 case SIOCGSTAMPNS:
866 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
867 break;
868 case SIOCADDRT:
869 case SIOCDELRT:
870 case SIOCRTMSG:
871 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
872 break;
873 case SIOCDARP:
874 case SIOCGARP:
875 case SIOCSARP:
876 err = arp_ioctl(net, cmd, (void __user *)arg);
877 break;
878 case SIOCGIFADDR:
879 case SIOCSIFADDR:
880 case SIOCGIFBRDADDR:
881 case SIOCSIFBRDADDR:
882 case SIOCGIFNETMASK:
883 case SIOCSIFNETMASK:
884 case SIOCGIFDSTADDR:
885 case SIOCSIFDSTADDR:
886 case SIOCSIFPFLAGS:
887 case SIOCGIFPFLAGS:
888 case SIOCSIFFLAGS:
889 err = devinet_ioctl(net, cmd, (void __user *)arg);
890 break;
891 default:
892 if (sk->sk_prot->ioctl)
893 err = sk->sk_prot->ioctl(sk, cmd, arg);
894 else
895 err = -ENOIOCTLCMD;
896 break;
897 }
898 return err;
899 }
900 EXPORT_SYMBOL(inet_ioctl);
901
902 #ifdef CONFIG_COMPAT
inet_compat_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)903 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
904 {
905 struct sock *sk = sock->sk;
906 int err = -ENOIOCTLCMD;
907
908 if (sk->sk_prot->compat_ioctl)
909 err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
910
911 return err;
912 }
913 #endif
914
915 const struct proto_ops inet_stream_ops = {
916 .family = PF_INET,
917 .owner = THIS_MODULE,
918 .release = inet_release,
919 .bind = inet_bind,
920 .connect = inet_stream_connect,
921 .socketpair = sock_no_socketpair,
922 .accept = inet_accept,
923 .getname = inet_getname,
924 .poll = tcp_poll,
925 .ioctl = inet_ioctl,
926 .listen = inet_listen,
927 .shutdown = inet_shutdown,
928 .setsockopt = sock_common_setsockopt,
929 .getsockopt = sock_common_getsockopt,
930 .sendmsg = inet_sendmsg,
931 .recvmsg = inet_recvmsg,
932 .mmap = sock_no_mmap,
933 .sendpage = inet_sendpage,
934 .splice_read = tcp_splice_read,
935 #ifdef CONFIG_COMPAT
936 .compat_setsockopt = compat_sock_common_setsockopt,
937 .compat_getsockopt = compat_sock_common_getsockopt,
938 .compat_ioctl = inet_compat_ioctl,
939 #endif
940 };
941 EXPORT_SYMBOL(inet_stream_ops);
942
943 const struct proto_ops inet_dgram_ops = {
944 .family = PF_INET,
945 .owner = THIS_MODULE,
946 .release = inet_release,
947 .bind = inet_bind,
948 .connect = inet_dgram_connect,
949 .socketpair = sock_no_socketpair,
950 .accept = sock_no_accept,
951 .getname = inet_getname,
952 .poll = udp_poll,
953 .ioctl = inet_ioctl,
954 .listen = sock_no_listen,
955 .shutdown = inet_shutdown,
956 .setsockopt = sock_common_setsockopt,
957 .getsockopt = sock_common_getsockopt,
958 .sendmsg = inet_sendmsg,
959 .recvmsg = inet_recvmsg,
960 .mmap = sock_no_mmap,
961 .sendpage = inet_sendpage,
962 #ifdef CONFIG_COMPAT
963 .compat_setsockopt = compat_sock_common_setsockopt,
964 .compat_getsockopt = compat_sock_common_getsockopt,
965 .compat_ioctl = inet_compat_ioctl,
966 #endif
967 };
968 EXPORT_SYMBOL(inet_dgram_ops);
969
970 /*
971 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
972 * udp_poll
973 */
974 static const struct proto_ops inet_sockraw_ops = {
975 .family = PF_INET,
976 .owner = THIS_MODULE,
977 .release = inet_release,
978 .bind = inet_bind,
979 .connect = inet_dgram_connect,
980 .socketpair = sock_no_socketpair,
981 .accept = sock_no_accept,
982 .getname = inet_getname,
983 .poll = datagram_poll,
984 .ioctl = inet_ioctl,
985 .listen = sock_no_listen,
986 .shutdown = inet_shutdown,
987 .setsockopt = sock_common_setsockopt,
988 .getsockopt = sock_common_getsockopt,
989 .sendmsg = inet_sendmsg,
990 .recvmsg = inet_recvmsg,
991 .mmap = sock_no_mmap,
992 .sendpage = inet_sendpage,
993 #ifdef CONFIG_COMPAT
994 .compat_setsockopt = compat_sock_common_setsockopt,
995 .compat_getsockopt = compat_sock_common_getsockopt,
996 .compat_ioctl = inet_compat_ioctl,
997 #endif
998 };
999
1000 static const struct net_proto_family inet_family_ops = {
1001 .family = PF_INET,
1002 .create = inet_create,
1003 .owner = THIS_MODULE,
1004 };
1005
1006 /* Upon startup we insert all the elements in inetsw_array[] into
1007 * the linked list inetsw.
1008 */
1009 static struct inet_protosw inetsw_array[] =
1010 {
1011 {
1012 .type = SOCK_STREAM,
1013 .protocol = IPPROTO_TCP,
1014 .prot = &tcp_prot,
1015 .ops = &inet_stream_ops,
1016 .no_check = 0,
1017 .flags = INET_PROTOSW_PERMANENT |
1018 INET_PROTOSW_ICSK,
1019 },
1020
1021 {
1022 .type = SOCK_DGRAM,
1023 .protocol = IPPROTO_UDP,
1024 .prot = &udp_prot,
1025 .ops = &inet_dgram_ops,
1026 .no_check = UDP_CSUM_DEFAULT,
1027 .flags = INET_PROTOSW_PERMANENT,
1028 },
1029
1030 {
1031 .type = SOCK_DGRAM,
1032 .protocol = IPPROTO_ICMP,
1033 .prot = &ping_prot,
1034 .ops = &inet_dgram_ops,
1035 .no_check = UDP_CSUM_DEFAULT,
1036 .flags = INET_PROTOSW_REUSE,
1037 },
1038
1039 {
1040 .type = SOCK_RAW,
1041 .protocol = IPPROTO_IP, /* wild card */
1042 .prot = &raw_prot,
1043 .ops = &inet_sockraw_ops,
1044 .no_check = UDP_CSUM_DEFAULT,
1045 .flags = INET_PROTOSW_REUSE,
1046 }
1047 };
1048
1049 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1050
inet_register_protosw(struct inet_protosw * p)1051 void inet_register_protosw(struct inet_protosw *p)
1052 {
1053 struct list_head *lh;
1054 struct inet_protosw *answer;
1055 int protocol = p->protocol;
1056 struct list_head *last_perm;
1057
1058 spin_lock_bh(&inetsw_lock);
1059
1060 if (p->type >= SOCK_MAX)
1061 goto out_illegal;
1062
1063 /* If we are trying to override a permanent protocol, bail. */
1064 answer = NULL;
1065 last_perm = &inetsw[p->type];
1066 list_for_each(lh, &inetsw[p->type]) {
1067 answer = list_entry(lh, struct inet_protosw, list);
1068
1069 /* Check only the non-wild match. */
1070 if (INET_PROTOSW_PERMANENT & answer->flags) {
1071 if (protocol == answer->protocol)
1072 break;
1073 last_perm = lh;
1074 }
1075
1076 answer = NULL;
1077 }
1078 if (answer)
1079 goto out_permanent;
1080
1081 /* Add the new entry after the last permanent entry if any, so that
1082 * the new entry does not override a permanent entry when matched with
1083 * a wild-card protocol. But it is allowed to override any existing
1084 * non-permanent entry. This means that when we remove this entry, the
1085 * system automatically returns to the old behavior.
1086 */
1087 list_add_rcu(&p->list, last_perm);
1088 out:
1089 spin_unlock_bh(&inetsw_lock);
1090
1091 return;
1092
1093 out_permanent:
1094 pr_err("Attempt to override permanent protocol %d\n", protocol);
1095 goto out;
1096
1097 out_illegal:
1098 pr_err("Ignoring attempt to register invalid socket type %d\n",
1099 p->type);
1100 goto out;
1101 }
1102 EXPORT_SYMBOL(inet_register_protosw);
1103
inet_unregister_protosw(struct inet_protosw * p)1104 void inet_unregister_protosw(struct inet_protosw *p)
1105 {
1106 if (INET_PROTOSW_PERMANENT & p->flags) {
1107 pr_err("Attempt to unregister permanent protocol %d\n",
1108 p->protocol);
1109 } else {
1110 spin_lock_bh(&inetsw_lock);
1111 list_del_rcu(&p->list);
1112 spin_unlock_bh(&inetsw_lock);
1113
1114 synchronize_net();
1115 }
1116 }
1117 EXPORT_SYMBOL(inet_unregister_protosw);
1118
1119 /*
1120 * Shall we try to damage output packets if routing dev changes?
1121 */
1122
1123 int sysctl_ip_dynaddr __read_mostly;
1124
inet_sk_reselect_saddr(struct sock * sk)1125 static int inet_sk_reselect_saddr(struct sock *sk)
1126 {
1127 struct inet_sock *inet = inet_sk(sk);
1128 __be32 old_saddr = inet->inet_saddr;
1129 __be32 daddr = inet->inet_daddr;
1130 struct flowi4 *fl4;
1131 struct rtable *rt;
1132 __be32 new_saddr;
1133 struct ip_options_rcu *inet_opt;
1134
1135 inet_opt = rcu_dereference_protected(inet->inet_opt,
1136 sock_owned_by_user(sk));
1137 if (inet_opt && inet_opt->opt.srr)
1138 daddr = inet_opt->opt.faddr;
1139
1140 /* Query new route. */
1141 fl4 = &inet->cork.fl.u.ip4;
1142 rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1143 sk->sk_bound_dev_if, sk->sk_protocol,
1144 inet->inet_sport, inet->inet_dport, sk, false);
1145 if (IS_ERR(rt))
1146 return PTR_ERR(rt);
1147
1148 sk_setup_caps(sk, &rt->dst);
1149
1150 new_saddr = fl4->saddr;
1151
1152 if (new_saddr == old_saddr)
1153 return 0;
1154
1155 if (sysctl_ip_dynaddr > 1) {
1156 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1157 __func__, &old_saddr, &new_saddr);
1158 }
1159
1160 inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1161
1162 /*
1163 * XXX The only one ugly spot where we need to
1164 * XXX really change the sockets identity after
1165 * XXX it has entered the hashes. -DaveM
1166 *
1167 * Besides that, it does not check for connection
1168 * uniqueness. Wait for troubles.
1169 */
1170 __sk_prot_rehash(sk);
1171 return 0;
1172 }
1173
inet_sk_rebuild_header(struct sock * sk)1174 int inet_sk_rebuild_header(struct sock *sk)
1175 {
1176 struct inet_sock *inet = inet_sk(sk);
1177 struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1178 __be32 daddr;
1179 struct ip_options_rcu *inet_opt;
1180 struct flowi4 *fl4;
1181 int err;
1182
1183 /* Route is OK, nothing to do. */
1184 if (rt)
1185 return 0;
1186
1187 /* Reroute. */
1188 rcu_read_lock();
1189 inet_opt = rcu_dereference(inet->inet_opt);
1190 daddr = inet->inet_daddr;
1191 if (inet_opt && inet_opt->opt.srr)
1192 daddr = inet_opt->opt.faddr;
1193 rcu_read_unlock();
1194 fl4 = &inet->cork.fl.u.ip4;
1195 rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1196 inet->inet_dport, inet->inet_sport,
1197 sk->sk_protocol, RT_CONN_FLAGS(sk),
1198 sk->sk_bound_dev_if);
1199 if (!IS_ERR(rt)) {
1200 err = 0;
1201 sk_setup_caps(sk, &rt->dst);
1202 } else {
1203 err = PTR_ERR(rt);
1204
1205 /* Routing failed... */
1206 sk->sk_route_caps = 0;
1207 /*
1208 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1209 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1210 */
1211 if (!sysctl_ip_dynaddr ||
1212 sk->sk_state != TCP_SYN_SENT ||
1213 (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1214 (err = inet_sk_reselect_saddr(sk)) != 0)
1215 sk->sk_err_soft = -err;
1216 }
1217
1218 return err;
1219 }
1220 EXPORT_SYMBOL(inet_sk_rebuild_header);
1221
inet_gso_send_check(struct sk_buff * skb)1222 static int inet_gso_send_check(struct sk_buff *skb)
1223 {
1224 const struct iphdr *iph;
1225 const struct net_protocol *ops;
1226 int proto;
1227 int ihl;
1228 int err = -EINVAL;
1229
1230 if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1231 goto out;
1232
1233 iph = ip_hdr(skb);
1234 ihl = iph->ihl * 4;
1235 if (ihl < sizeof(*iph))
1236 goto out;
1237
1238 if (unlikely(!pskb_may_pull(skb, ihl)))
1239 goto out;
1240
1241 __skb_pull(skb, ihl);
1242 skb_reset_transport_header(skb);
1243 iph = ip_hdr(skb);
1244 proto = iph->protocol & (MAX_INET_PROTOS - 1);
1245 err = -EPROTONOSUPPORT;
1246
1247 rcu_read_lock();
1248 ops = rcu_dereference(inet_protos[proto]);
1249 if (likely(ops && ops->gso_send_check))
1250 err = ops->gso_send_check(skb);
1251 rcu_read_unlock();
1252
1253 out:
1254 return err;
1255 }
1256
inet_gso_segment(struct sk_buff * skb,netdev_features_t features)1257 static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1258 netdev_features_t features)
1259 {
1260 struct sk_buff *segs = ERR_PTR(-EINVAL);
1261 struct iphdr *iph;
1262 const struct net_protocol *ops;
1263 int proto;
1264 int ihl;
1265 int id;
1266 unsigned int offset = 0;
1267
1268 if (!(features & NETIF_F_V4_CSUM))
1269 features &= ~NETIF_F_SG;
1270
1271 if (unlikely(skb_shinfo(skb)->gso_type &
1272 ~(SKB_GSO_TCPV4 |
1273 SKB_GSO_UDP |
1274 SKB_GSO_DODGY |
1275 SKB_GSO_TCP_ECN |
1276 0)))
1277 goto out;
1278
1279 if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1280 goto out;
1281
1282 iph = ip_hdr(skb);
1283 ihl = iph->ihl * 4;
1284 if (ihl < sizeof(*iph))
1285 goto out;
1286
1287 if (unlikely(!pskb_may_pull(skb, ihl)))
1288 goto out;
1289
1290 __skb_pull(skb, ihl);
1291 skb_reset_transport_header(skb);
1292 iph = ip_hdr(skb);
1293 id = ntohs(iph->id);
1294 proto = iph->protocol & (MAX_INET_PROTOS - 1);
1295 segs = ERR_PTR(-EPROTONOSUPPORT);
1296
1297 rcu_read_lock();
1298 ops = rcu_dereference(inet_protos[proto]);
1299 if (likely(ops && ops->gso_segment))
1300 segs = ops->gso_segment(skb, features);
1301 rcu_read_unlock();
1302
1303 if (!segs || IS_ERR(segs))
1304 goto out;
1305
1306 skb = segs;
1307 do {
1308 iph = ip_hdr(skb);
1309 if (proto == IPPROTO_UDP) {
1310 iph->id = htons(id);
1311 iph->frag_off = htons(offset >> 3);
1312 if (skb->next != NULL)
1313 iph->frag_off |= htons(IP_MF);
1314 offset += (skb->len - skb->mac_len - iph->ihl * 4);
1315 } else
1316 iph->id = htons(id++);
1317 iph->tot_len = htons(skb->len - skb->mac_len);
1318 iph->check = 0;
1319 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1320 } while ((skb = skb->next));
1321
1322 out:
1323 return segs;
1324 }
1325
inet_gro_receive(struct sk_buff ** head,struct sk_buff * skb)1326 static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1327 struct sk_buff *skb)
1328 {
1329 const struct net_protocol *ops;
1330 struct sk_buff **pp = NULL;
1331 struct sk_buff *p;
1332 const struct iphdr *iph;
1333 unsigned int hlen;
1334 unsigned int off;
1335 unsigned int id;
1336 int flush = 1;
1337 int proto;
1338
1339 off = skb_gro_offset(skb);
1340 hlen = off + sizeof(*iph);
1341 iph = skb_gro_header_fast(skb, off);
1342 if (skb_gro_header_hard(skb, hlen)) {
1343 iph = skb_gro_header_slow(skb, hlen, off);
1344 if (unlikely(!iph))
1345 goto out;
1346 }
1347
1348 proto = iph->protocol & (MAX_INET_PROTOS - 1);
1349
1350 rcu_read_lock();
1351 ops = rcu_dereference(inet_protos[proto]);
1352 if (!ops || !ops->gro_receive)
1353 goto out_unlock;
1354
1355 if (*(u8 *)iph != 0x45)
1356 goto out_unlock;
1357
1358 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1359 goto out_unlock;
1360
1361 id = ntohl(*(__be32 *)&iph->id);
1362 flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1363 id >>= 16;
1364
1365 for (p = *head; p; p = p->next) {
1366 struct iphdr *iph2;
1367
1368 if (!NAPI_GRO_CB(p)->same_flow)
1369 continue;
1370
1371 iph2 = ip_hdr(p);
1372
1373 if ((iph->protocol ^ iph2->protocol) |
1374 (iph->tos ^ iph2->tos) |
1375 ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1376 ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1377 NAPI_GRO_CB(p)->same_flow = 0;
1378 continue;
1379 }
1380
1381 /* All fields must match except length and checksum. */
1382 NAPI_GRO_CB(p)->flush |=
1383 (iph->ttl ^ iph2->ttl) |
1384 ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1385
1386 NAPI_GRO_CB(p)->flush |= flush;
1387 }
1388
1389 NAPI_GRO_CB(skb)->flush |= flush;
1390 skb_gro_pull(skb, sizeof(*iph));
1391 skb_set_transport_header(skb, skb_gro_offset(skb));
1392
1393 pp = ops->gro_receive(head, skb);
1394
1395 out_unlock:
1396 rcu_read_unlock();
1397
1398 out:
1399 NAPI_GRO_CB(skb)->flush |= flush;
1400
1401 return pp;
1402 }
1403
inet_gro_complete(struct sk_buff * skb)1404 static int inet_gro_complete(struct sk_buff *skb)
1405 {
1406 const struct net_protocol *ops;
1407 struct iphdr *iph = ip_hdr(skb);
1408 int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1409 int err = -ENOSYS;
1410 __be16 newlen = htons(skb->len - skb_network_offset(skb));
1411
1412 csum_replace2(&iph->check, iph->tot_len, newlen);
1413 iph->tot_len = newlen;
1414
1415 rcu_read_lock();
1416 ops = rcu_dereference(inet_protos[proto]);
1417 if (WARN_ON(!ops || !ops->gro_complete))
1418 goto out_unlock;
1419
1420 err = ops->gro_complete(skb);
1421
1422 out_unlock:
1423 rcu_read_unlock();
1424
1425 return err;
1426 }
1427
inet_ctl_sock_create(struct sock ** sk,unsigned short family,unsigned short type,unsigned char protocol,struct net * net)1428 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1429 unsigned short type, unsigned char protocol,
1430 struct net *net)
1431 {
1432 struct socket *sock;
1433 int rc = sock_create_kern(family, type, protocol, &sock);
1434
1435 if (rc == 0) {
1436 *sk = sock->sk;
1437 (*sk)->sk_allocation = GFP_ATOMIC;
1438 /*
1439 * Unhash it so that IP input processing does not even see it,
1440 * we do not wish this socket to see incoming packets.
1441 */
1442 (*sk)->sk_prot->unhash(*sk);
1443
1444 sk_change_net(*sk, net);
1445 }
1446 return rc;
1447 }
1448 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1449
snmp_fold_field(void __percpu * mib[],int offt)1450 unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1451 {
1452 unsigned long res = 0;
1453 int i, j;
1454
1455 for_each_possible_cpu(i) {
1456 for (j = 0; j < SNMP_ARRAY_SZ; j++)
1457 res += *(((unsigned long *) per_cpu_ptr(mib[j], i)) + offt);
1458 }
1459 return res;
1460 }
1461 EXPORT_SYMBOL_GPL(snmp_fold_field);
1462
1463 #if BITS_PER_LONG==32
1464
snmp_fold_field64(void __percpu * mib[],int offt,size_t syncp_offset)1465 u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_offset)
1466 {
1467 u64 res = 0;
1468 int cpu;
1469
1470 for_each_possible_cpu(cpu) {
1471 void *bhptr;
1472 struct u64_stats_sync *syncp;
1473 u64 v;
1474 unsigned int start;
1475
1476 bhptr = per_cpu_ptr(mib[0], cpu);
1477 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1478 do {
1479 start = u64_stats_fetch_begin_bh(syncp);
1480 v = *(((u64 *) bhptr) + offt);
1481 } while (u64_stats_fetch_retry_bh(syncp, start));
1482
1483 res += v;
1484 }
1485 return res;
1486 }
1487 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1488 #endif
1489
snmp_mib_init(void __percpu * ptr[2],size_t mibsize,size_t align)1490 int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align)
1491 {
1492 BUG_ON(ptr == NULL);
1493 ptr[0] = __alloc_percpu(mibsize, align);
1494 if (!ptr[0])
1495 return -ENOMEM;
1496 #if SNMP_ARRAY_SZ == 2
1497 ptr[1] = __alloc_percpu(mibsize, align);
1498 if (!ptr[1]) {
1499 free_percpu(ptr[0]);
1500 ptr[0] = NULL;
1501 return -ENOMEM;
1502 }
1503 #endif
1504 return 0;
1505 }
1506 EXPORT_SYMBOL_GPL(snmp_mib_init);
1507
snmp_mib_free(void __percpu * ptr[SNMP_ARRAY_SZ])1508 void snmp_mib_free(void __percpu *ptr[SNMP_ARRAY_SZ])
1509 {
1510 int i;
1511
1512 BUG_ON(ptr == NULL);
1513 for (i = 0; i < SNMP_ARRAY_SZ; i++) {
1514 free_percpu(ptr[i]);
1515 ptr[i] = NULL;
1516 }
1517 }
1518 EXPORT_SYMBOL_GPL(snmp_mib_free);
1519
1520 #ifdef CONFIG_IP_MULTICAST
1521 static const struct net_protocol igmp_protocol = {
1522 .handler = igmp_rcv,
1523 .netns_ok = 1,
1524 };
1525 #endif
1526
1527 static const struct net_protocol tcp_protocol = {
1528 .handler = tcp_v4_rcv,
1529 .err_handler = tcp_v4_err,
1530 .gso_send_check = tcp_v4_gso_send_check,
1531 .gso_segment = tcp_tso_segment,
1532 .gro_receive = tcp4_gro_receive,
1533 .gro_complete = tcp4_gro_complete,
1534 .no_policy = 1,
1535 .netns_ok = 1,
1536 };
1537
1538 static const struct net_protocol udp_protocol = {
1539 .handler = udp_rcv,
1540 .err_handler = udp_err,
1541 .gso_send_check = udp4_ufo_send_check,
1542 .gso_segment = udp4_ufo_fragment,
1543 .no_policy = 1,
1544 .netns_ok = 1,
1545 };
1546
1547 static const struct net_protocol icmp_protocol = {
1548 .handler = icmp_rcv,
1549 .err_handler = ping_err,
1550 .no_policy = 1,
1551 .netns_ok = 1,
1552 };
1553
ipv4_mib_init_net(struct net * net)1554 static __net_init int ipv4_mib_init_net(struct net *net)
1555 {
1556 if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1557 sizeof(struct tcp_mib),
1558 __alignof__(struct tcp_mib)) < 0)
1559 goto err_tcp_mib;
1560 if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1561 sizeof(struct ipstats_mib),
1562 __alignof__(struct ipstats_mib)) < 0)
1563 goto err_ip_mib;
1564 if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1565 sizeof(struct linux_mib),
1566 __alignof__(struct linux_mib)) < 0)
1567 goto err_net_mib;
1568 if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1569 sizeof(struct udp_mib),
1570 __alignof__(struct udp_mib)) < 0)
1571 goto err_udp_mib;
1572 if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1573 sizeof(struct udp_mib),
1574 __alignof__(struct udp_mib)) < 0)
1575 goto err_udplite_mib;
1576 if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1577 sizeof(struct icmp_mib),
1578 __alignof__(struct icmp_mib)) < 0)
1579 goto err_icmp_mib;
1580 net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1581 GFP_KERNEL);
1582 if (!net->mib.icmpmsg_statistics)
1583 goto err_icmpmsg_mib;
1584
1585 tcp_mib_init(net);
1586 return 0;
1587
1588 err_icmpmsg_mib:
1589 snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1590 err_icmp_mib:
1591 snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1592 err_udplite_mib:
1593 snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1594 err_udp_mib:
1595 snmp_mib_free((void __percpu **)net->mib.net_statistics);
1596 err_net_mib:
1597 snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1598 err_ip_mib:
1599 snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1600 err_tcp_mib:
1601 return -ENOMEM;
1602 }
1603
ipv4_mib_exit_net(struct net * net)1604 static __net_exit void ipv4_mib_exit_net(struct net *net)
1605 {
1606 kfree(net->mib.icmpmsg_statistics);
1607 snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1608 snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1609 snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1610 snmp_mib_free((void __percpu **)net->mib.net_statistics);
1611 snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1612 snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1613 }
1614
1615 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1616 .init = ipv4_mib_init_net,
1617 .exit = ipv4_mib_exit_net,
1618 };
1619
init_ipv4_mibs(void)1620 static int __init init_ipv4_mibs(void)
1621 {
1622 return register_pernet_subsys(&ipv4_mib_ops);
1623 }
1624
1625 static int ipv4_proc_init(void);
1626
1627 /*
1628 * IP protocol layer initialiser
1629 */
1630
1631 static struct packet_type ip_packet_type __read_mostly = {
1632 .type = cpu_to_be16(ETH_P_IP),
1633 .func = ip_rcv,
1634 .gso_send_check = inet_gso_send_check,
1635 .gso_segment = inet_gso_segment,
1636 .gro_receive = inet_gro_receive,
1637 .gro_complete = inet_gro_complete,
1638 };
1639
inet_init(void)1640 static int __init inet_init(void)
1641 {
1642 struct sk_buff *dummy_skb;
1643 struct inet_protosw *q;
1644 struct list_head *r;
1645 int rc = -EINVAL;
1646
1647 BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1648
1649 sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1650 if (!sysctl_local_reserved_ports)
1651 goto out;
1652
1653 rc = proto_register(&tcp_prot, 1);
1654 if (rc)
1655 goto out_free_reserved_ports;
1656
1657 rc = proto_register(&udp_prot, 1);
1658 if (rc)
1659 goto out_unregister_tcp_proto;
1660
1661 rc = proto_register(&raw_prot, 1);
1662 if (rc)
1663 goto out_unregister_udp_proto;
1664
1665 rc = proto_register(&ping_prot, 1);
1666 if (rc)
1667 goto out_unregister_raw_proto;
1668
1669 /*
1670 * Tell SOCKET that we are alive...
1671 */
1672
1673 (void)sock_register(&inet_family_ops);
1674
1675 #ifdef CONFIG_SYSCTL
1676 ip_static_sysctl_init();
1677 #endif
1678
1679 tcp_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;
1680
1681 /*
1682 * Add all the base protocols.
1683 */
1684
1685 if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1686 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1687 if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1688 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1689 if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1690 pr_crit("%s: Cannot add TCP protocol\n", __func__);
1691 #ifdef CONFIG_IP_MULTICAST
1692 if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1693 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1694 #endif
1695
1696 /* Register the socket-side information for inet_create. */
1697 for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1698 INIT_LIST_HEAD(r);
1699
1700 for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1701 inet_register_protosw(q);
1702
1703 /*
1704 * Set the ARP module up
1705 */
1706
1707 arp_init();
1708
1709 /*
1710 * Set the IP module up
1711 */
1712
1713 ip_init();
1714
1715 tcp_v4_init();
1716
1717 /* Setup TCP slab cache for open requests. */
1718 tcp_init();
1719
1720 /* Setup UDP memory threshold */
1721 udp_init();
1722
1723 /* Add UDP-Lite (RFC 3828) */
1724 udplite4_register();
1725
1726 ping_init();
1727
1728 /*
1729 * Set the ICMP layer up
1730 */
1731
1732 if (icmp_init() < 0)
1733 panic("Failed to create the ICMP control socket.\n");
1734
1735 /*
1736 * Initialise the multicast router
1737 */
1738 #if defined(CONFIG_IP_MROUTE)
1739 if (ip_mr_init())
1740 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
1741 #endif
1742 /*
1743 * Initialise per-cpu ipv4 mibs
1744 */
1745
1746 if (init_ipv4_mibs())
1747 pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
1748
1749 ipv4_proc_init();
1750
1751 ipfrag_init();
1752
1753 dev_add_pack(&ip_packet_type);
1754
1755 rc = 0;
1756 out:
1757 return rc;
1758 out_unregister_raw_proto:
1759 proto_unregister(&raw_prot);
1760 out_unregister_udp_proto:
1761 proto_unregister(&udp_prot);
1762 out_unregister_tcp_proto:
1763 proto_unregister(&tcp_prot);
1764 out_free_reserved_ports:
1765 kfree(sysctl_local_reserved_ports);
1766 goto out;
1767 }
1768
1769 fs_initcall(inet_init);
1770
1771 /* ------------------------------------------------------------------------ */
1772
1773 #ifdef CONFIG_PROC_FS
ipv4_proc_init(void)1774 static int __init ipv4_proc_init(void)
1775 {
1776 int rc = 0;
1777
1778 if (raw_proc_init())
1779 goto out_raw;
1780 if (tcp4_proc_init())
1781 goto out_tcp;
1782 if (udp4_proc_init())
1783 goto out_udp;
1784 if (ping_proc_init())
1785 goto out_ping;
1786 if (ip_misc_proc_init())
1787 goto out_misc;
1788 out:
1789 return rc;
1790 out_misc:
1791 ping_proc_exit();
1792 out_ping:
1793 udp4_proc_exit();
1794 out_udp:
1795 tcp4_proc_exit();
1796 out_tcp:
1797 raw_proc_exit();
1798 out_raw:
1799 rc = -ENOMEM;
1800 goto out;
1801 }
1802
1803 #else /* CONFIG_PROC_FS */
ipv4_proc_init(void)1804 static int __init ipv4_proc_init(void)
1805 {
1806 return 0;
1807 }
1808 #endif /* CONFIG_PROC_FS */
1809
1810 MODULE_ALIAS_NETPROTO(PF_INET);
1811
1812