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/inet_common.h>
115 #include <net/xfrm.h>
116 #include <net/net_namespace.h>
117 #include <net/secure_seq.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 /* New destruction routine */
130
inet_sock_destruct(struct sock * sk)131 void inet_sock_destruct(struct sock *sk)
132 {
133 struct inet_sock *inet = inet_sk(sk);
134
135 __skb_queue_purge(&sk->sk_receive_queue);
136 __skb_queue_purge(&sk->sk_error_queue);
137
138 sk_mem_reclaim(sk);
139
140 if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
141 pr_err("Attempt to release TCP socket in state %d %p\n",
142 sk->sk_state, sk);
143 return;
144 }
145 if (!sock_flag(sk, SOCK_DEAD)) {
146 pr_err("Attempt to release alive inet socket %p\n", sk);
147 return;
148 }
149
150 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
151 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
152 WARN_ON(sk->sk_wmem_queued);
153 WARN_ON(sk->sk_forward_alloc);
154
155 kfree(rcu_dereference_protected(inet->inet_opt, 1));
156 dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
157 dst_release(sk->sk_rx_dst);
158 sk_refcnt_debug_dec(sk);
159 }
160 EXPORT_SYMBOL(inet_sock_destruct);
161
162 /*
163 * The routines beyond this point handle the behaviour of an AF_INET
164 * socket object. Mostly it punts to the subprotocols of IP to do
165 * the work.
166 */
167
168 /*
169 * Automatically bind an unbound socket.
170 */
171
inet_autobind(struct sock * sk)172 static int inet_autobind(struct sock *sk)
173 {
174 struct inet_sock *inet;
175 /* We may need to bind the socket. */
176 lock_sock(sk);
177 inet = inet_sk(sk);
178 if (!inet->inet_num) {
179 if (sk->sk_prot->get_port(sk, 0)) {
180 release_sock(sk);
181 return -EAGAIN;
182 }
183 inet->inet_sport = htons(inet->inet_num);
184 }
185 release_sock(sk);
186 return 0;
187 }
188
189 /*
190 * Move a socket into listening state.
191 */
inet_listen(struct socket * sock,int backlog)192 int inet_listen(struct socket *sock, int backlog)
193 {
194 struct sock *sk = sock->sk;
195 unsigned char old_state;
196 int err;
197
198 lock_sock(sk);
199
200 err = -EINVAL;
201 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
202 goto out;
203
204 old_state = sk->sk_state;
205 if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
206 goto out;
207
208 /* Really, if the socket is already in listen state
209 * we can only allow the backlog to be adjusted.
210 */
211 if (old_state != TCP_LISTEN) {
212 /* Check special setups for testing purpose to enable TFO w/o
213 * requiring TCP_FASTOPEN sockopt.
214 * Note that only TCP sockets (SOCK_STREAM) will reach here.
215 * Also fastopenq may already been allocated because this
216 * socket was in TCP_LISTEN state previously but was
217 * shutdown() (rather than close()).
218 */
219 if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) != 0 &&
220 !inet_csk(sk)->icsk_accept_queue.fastopenq) {
221 if ((sysctl_tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) != 0)
222 err = fastopen_init_queue(sk, backlog);
223 else if ((sysctl_tcp_fastopen &
224 TFO_SERVER_WO_SOCKOPT2) != 0)
225 err = fastopen_init_queue(sk,
226 ((uint)sysctl_tcp_fastopen) >> 16);
227 else
228 err = 0;
229 if (err)
230 goto out;
231
232 tcp_fastopen_init_key_once(true);
233 }
234 err = inet_csk_listen_start(sk, backlog);
235 if (err)
236 goto out;
237 }
238 sk->sk_max_ack_backlog = backlog;
239 err = 0;
240
241 out:
242 release_sock(sk);
243 return err;
244 }
245 EXPORT_SYMBOL(inet_listen);
246
247 /*
248 * Create an inet socket.
249 */
250
inet_create(struct net * net,struct socket * sock,int protocol,int kern)251 static int inet_create(struct net *net, struct socket *sock, int protocol,
252 int kern)
253 {
254 struct sock *sk;
255 struct inet_protosw *answer;
256 struct inet_sock *inet;
257 struct proto *answer_prot;
258 unsigned char answer_flags;
259 int try_loading_module = 0;
260 int err;
261
262 if (protocol < 0 || protocol >= IPPROTO_MAX)
263 return -EINVAL;
264
265 sock->state = SS_UNCONNECTED;
266
267 /* Look for the requested type/protocol pair. */
268 lookup_protocol:
269 err = -ESOCKTNOSUPPORT;
270 rcu_read_lock();
271 list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
272
273 err = 0;
274 /* Check the non-wild match. */
275 if (protocol == answer->protocol) {
276 if (protocol != IPPROTO_IP)
277 break;
278 } else {
279 /* Check for the two wild cases. */
280 if (IPPROTO_IP == protocol) {
281 protocol = answer->protocol;
282 break;
283 }
284 if (IPPROTO_IP == answer->protocol)
285 break;
286 }
287 err = -EPROTONOSUPPORT;
288 }
289
290 if (unlikely(err)) {
291 if (try_loading_module < 2) {
292 rcu_read_unlock();
293 /*
294 * Be more specific, e.g. net-pf-2-proto-132-type-1
295 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
296 */
297 if (++try_loading_module == 1)
298 request_module("net-pf-%d-proto-%d-type-%d",
299 PF_INET, protocol, sock->type);
300 /*
301 * Fall back to generic, e.g. net-pf-2-proto-132
302 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
303 */
304 else
305 request_module("net-pf-%d-proto-%d",
306 PF_INET, protocol);
307 goto lookup_protocol;
308 } else
309 goto out_rcu_unlock;
310 }
311
312 err = -EPERM;
313 if (sock->type == SOCK_RAW && !kern &&
314 !ns_capable(net->user_ns, CAP_NET_RAW))
315 goto out_rcu_unlock;
316
317 sock->ops = answer->ops;
318 answer_prot = answer->prot;
319 answer_flags = answer->flags;
320 rcu_read_unlock();
321
322 WARN_ON(!answer_prot->slab);
323
324 err = -ENOBUFS;
325 sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
326 if (!sk)
327 goto out;
328
329 err = 0;
330 if (INET_PROTOSW_REUSE & answer_flags)
331 sk->sk_reuse = SK_CAN_REUSE;
332
333 inet = inet_sk(sk);
334 inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
335
336 inet->nodefrag = 0;
337
338 if (SOCK_RAW == sock->type) {
339 inet->inet_num = protocol;
340 if (IPPROTO_RAW == protocol)
341 inet->hdrincl = 1;
342 }
343
344 if (net->ipv4.sysctl_ip_no_pmtu_disc)
345 inet->pmtudisc = IP_PMTUDISC_DONT;
346 else
347 inet->pmtudisc = IP_PMTUDISC_WANT;
348
349 inet->inet_id = 0;
350
351 sock_init_data(sock, sk);
352
353 sk->sk_destruct = inet_sock_destruct;
354 sk->sk_protocol = protocol;
355 sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
356
357 inet->uc_ttl = -1;
358 inet->mc_loop = 1;
359 inet->mc_ttl = 1;
360 inet->mc_all = 1;
361 inet->mc_index = 0;
362 inet->mc_list = NULL;
363 inet->rcv_tos = 0;
364
365 sk_refcnt_debug_inc(sk);
366
367 if (inet->inet_num) {
368 /* It assumes that any protocol which allows
369 * the user to assign a number at socket
370 * creation time automatically
371 * shares.
372 */
373 inet->inet_sport = htons(inet->inet_num);
374 /* Add to protocol hash chains. */
375 sk->sk_prot->hash(sk);
376 }
377
378 if (sk->sk_prot->init) {
379 err = sk->sk_prot->init(sk);
380 if (err)
381 sk_common_release(sk);
382 }
383 out:
384 return err;
385 out_rcu_unlock:
386 rcu_read_unlock();
387 goto out;
388 }
389
390
391 /*
392 * The peer socket should always be NULL (or else). When we call this
393 * function we are destroying the object and from then on nobody
394 * should refer to it.
395 */
inet_release(struct socket * sock)396 int inet_release(struct socket *sock)
397 {
398 struct sock *sk = sock->sk;
399
400 if (sk) {
401 long timeout;
402
403 /* Applications forget to leave groups before exiting */
404 ip_mc_drop_socket(sk);
405
406 /* If linger is set, we don't return until the close
407 * is complete. Otherwise we return immediately. The
408 * actually closing is done the same either way.
409 *
410 * If the close is due to the process exiting, we never
411 * linger..
412 */
413 timeout = 0;
414 if (sock_flag(sk, SOCK_LINGER) &&
415 !(current->flags & PF_EXITING))
416 timeout = sk->sk_lingertime;
417 sock->sk = NULL;
418 sk->sk_prot->close(sk, timeout);
419 }
420 return 0;
421 }
422 EXPORT_SYMBOL(inet_release);
423
inet_bind(struct socket * sock,struct sockaddr * uaddr,int addr_len)424 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
425 {
426 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
427 struct sock *sk = sock->sk;
428 struct inet_sock *inet = inet_sk(sk);
429 struct net *net = sock_net(sk);
430 unsigned short snum;
431 int chk_addr_ret;
432 int err;
433
434 /* If the socket has its own bind function then use it. (RAW) */
435 if (sk->sk_prot->bind) {
436 err = sk->sk_prot->bind(sk, uaddr, addr_len);
437 goto out;
438 }
439 err = -EINVAL;
440 if (addr_len < sizeof(struct sockaddr_in))
441 goto out;
442
443 if (addr->sin_family != AF_INET) {
444 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
445 * only if s_addr is INADDR_ANY.
446 */
447 err = -EAFNOSUPPORT;
448 if (addr->sin_family != AF_UNSPEC ||
449 addr->sin_addr.s_addr != htonl(INADDR_ANY))
450 goto out;
451 }
452
453 chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
454
455 /* Not specified by any standard per-se, however it breaks too
456 * many applications when removed. It is unfortunate since
457 * allowing applications to make a non-local bind solves
458 * several problems with systems using dynamic addressing.
459 * (ie. your servers still start up even if your ISDN link
460 * is temporarily down)
461 */
462 err = -EADDRNOTAVAIL;
463 if (!net->ipv4.sysctl_ip_nonlocal_bind &&
464 !(inet->freebind || inet->transparent) &&
465 addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
466 chk_addr_ret != RTN_LOCAL &&
467 chk_addr_ret != RTN_MULTICAST &&
468 chk_addr_ret != RTN_BROADCAST)
469 goto out;
470
471 snum = ntohs(addr->sin_port);
472 err = -EACCES;
473 if (snum && snum < PROT_SOCK &&
474 !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
475 goto out;
476
477 /* We keep a pair of addresses. rcv_saddr is the one
478 * used by hash lookups, and saddr is used for transmit.
479 *
480 * In the BSD API these are the same except where it
481 * would be illegal to use them (multicast/broadcast) in
482 * which case the sending device address is used.
483 */
484 lock_sock(sk);
485
486 /* Check these errors (active socket, double bind). */
487 err = -EINVAL;
488 if (sk->sk_state != TCP_CLOSE || inet->inet_num)
489 goto out_release_sock;
490
491 inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
492 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
493 inet->inet_saddr = 0; /* Use device */
494
495 /* Make sure we are allowed to bind here. */
496 if (sk->sk_prot->get_port(sk, snum)) {
497 inet->inet_saddr = inet->inet_rcv_saddr = 0;
498 err = -EADDRINUSE;
499 goto out_release_sock;
500 }
501
502 if (inet->inet_rcv_saddr)
503 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
504 if (snum)
505 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
506 inet->inet_sport = htons(inet->inet_num);
507 inet->inet_daddr = 0;
508 inet->inet_dport = 0;
509 sk_dst_reset(sk);
510 err = 0;
511 out_release_sock:
512 release_sock(sk);
513 out:
514 return err;
515 }
516 EXPORT_SYMBOL(inet_bind);
517
inet_dgram_connect(struct socket * sock,struct sockaddr * uaddr,int addr_len,int flags)518 int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
519 int addr_len, int flags)
520 {
521 struct sock *sk = sock->sk;
522
523 if (addr_len < sizeof(uaddr->sa_family))
524 return -EINVAL;
525 if (uaddr->sa_family == AF_UNSPEC)
526 return sk->sk_prot->disconnect(sk, flags);
527
528 if (!inet_sk(sk)->inet_num && inet_autobind(sk))
529 return -EAGAIN;
530 return sk->sk_prot->connect(sk, uaddr, addr_len);
531 }
532 EXPORT_SYMBOL(inet_dgram_connect);
533
inet_wait_for_connect(struct sock * sk,long timeo,int writebias)534 static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
535 {
536 DEFINE_WAIT(wait);
537
538 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
539 sk->sk_write_pending += writebias;
540
541 /* Basic assumption: if someone sets sk->sk_err, he _must_
542 * change state of the socket from TCP_SYN_*.
543 * Connect() does not allow to get error notifications
544 * without closing the socket.
545 */
546 while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
547 release_sock(sk);
548 timeo = schedule_timeout(timeo);
549 lock_sock(sk);
550 if (signal_pending(current) || !timeo)
551 break;
552 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
553 }
554 finish_wait(sk_sleep(sk), &wait);
555 sk->sk_write_pending -= writebias;
556 return timeo;
557 }
558
559 /*
560 * Connect to a remote host. There is regrettably still a little
561 * TCP 'magic' in here.
562 */
__inet_stream_connect(struct socket * sock,struct sockaddr * uaddr,int addr_len,int flags)563 int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
564 int addr_len, int flags)
565 {
566 struct sock *sk = sock->sk;
567 int err;
568 long timeo;
569
570 if (addr_len < sizeof(uaddr->sa_family))
571 return -EINVAL;
572
573 if (uaddr->sa_family == AF_UNSPEC) {
574 err = sk->sk_prot->disconnect(sk, flags);
575 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
576 goto out;
577 }
578
579 switch (sock->state) {
580 default:
581 err = -EINVAL;
582 goto out;
583 case SS_CONNECTED:
584 err = -EISCONN;
585 goto out;
586 case SS_CONNECTING:
587 err = -EALREADY;
588 /* Fall out of switch with err, set for this state */
589 break;
590 case SS_UNCONNECTED:
591 err = -EISCONN;
592 if (sk->sk_state != TCP_CLOSE)
593 goto out;
594
595 err = sk->sk_prot->connect(sk, uaddr, addr_len);
596 if (err < 0)
597 goto out;
598
599 sock->state = SS_CONNECTING;
600
601 /* Just entered SS_CONNECTING state; the only
602 * difference is that return value in non-blocking
603 * case is EINPROGRESS, rather than EALREADY.
604 */
605 err = -EINPROGRESS;
606 break;
607 }
608
609 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
610
611 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
612 int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
613 tcp_sk(sk)->fastopen_req &&
614 tcp_sk(sk)->fastopen_req->data ? 1 : 0;
615
616 /* Error code is set above */
617 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
618 goto out;
619
620 err = sock_intr_errno(timeo);
621 if (signal_pending(current))
622 goto out;
623 }
624
625 /* Connection was closed by RST, timeout, ICMP error
626 * or another process disconnected us.
627 */
628 if (sk->sk_state == TCP_CLOSE)
629 goto sock_error;
630
631 /* sk->sk_err may be not zero now, if RECVERR was ordered by user
632 * and error was received after socket entered established state.
633 * Hence, it is handled normally after connect() return successfully.
634 */
635
636 sock->state = SS_CONNECTED;
637 err = 0;
638 out:
639 return err;
640
641 sock_error:
642 err = sock_error(sk) ? : -ECONNABORTED;
643 sock->state = SS_UNCONNECTED;
644 if (sk->sk_prot->disconnect(sk, flags))
645 sock->state = SS_DISCONNECTING;
646 goto out;
647 }
648 EXPORT_SYMBOL(__inet_stream_connect);
649
inet_stream_connect(struct socket * sock,struct sockaddr * uaddr,int addr_len,int flags)650 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
651 int addr_len, int flags)
652 {
653 int err;
654
655 lock_sock(sock->sk);
656 err = __inet_stream_connect(sock, uaddr, addr_len, flags);
657 release_sock(sock->sk);
658 return err;
659 }
660 EXPORT_SYMBOL(inet_stream_connect);
661
662 /*
663 * Accept a pending connection. The TCP layer now gives BSD semantics.
664 */
665
inet_accept(struct socket * sock,struct socket * newsock,int flags)666 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
667 {
668 struct sock *sk1 = sock->sk;
669 int err = -EINVAL;
670 struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
671
672 if (!sk2)
673 goto do_err;
674
675 lock_sock(sk2);
676
677 sock_rps_record_flow(sk2);
678 WARN_ON(!((1 << sk2->sk_state) &
679 (TCPF_ESTABLISHED | TCPF_SYN_RECV |
680 TCPF_CLOSE_WAIT | TCPF_CLOSE)));
681
682 sock_graft(sk2, newsock);
683
684 newsock->state = SS_CONNECTED;
685 err = 0;
686 release_sock(sk2);
687 do_err:
688 return err;
689 }
690 EXPORT_SYMBOL(inet_accept);
691
692
693 /*
694 * This does both peername and sockname.
695 */
inet_getname(struct socket * sock,struct sockaddr * uaddr,int * uaddr_len,int peer)696 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
697 int *uaddr_len, int peer)
698 {
699 struct sock *sk = sock->sk;
700 struct inet_sock *inet = inet_sk(sk);
701 DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
702
703 sin->sin_family = AF_INET;
704 if (peer) {
705 if (!inet->inet_dport ||
706 (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
707 peer == 1))
708 return -ENOTCONN;
709 sin->sin_port = inet->inet_dport;
710 sin->sin_addr.s_addr = inet->inet_daddr;
711 } else {
712 __be32 addr = inet->inet_rcv_saddr;
713 if (!addr)
714 addr = inet->inet_saddr;
715 sin->sin_port = inet->inet_sport;
716 sin->sin_addr.s_addr = addr;
717 }
718 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
719 *uaddr_len = sizeof(*sin);
720 return 0;
721 }
722 EXPORT_SYMBOL(inet_getname);
723
inet_sendmsg(struct socket * sock,struct msghdr * msg,size_t size)724 int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
725 {
726 struct sock *sk = sock->sk;
727
728 sock_rps_record_flow(sk);
729
730 /* We may need to bind the socket. */
731 if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
732 inet_autobind(sk))
733 return -EAGAIN;
734
735 return sk->sk_prot->sendmsg(sk, msg, size);
736 }
737 EXPORT_SYMBOL(inet_sendmsg);
738
inet_sendpage(struct socket * sock,struct page * page,int offset,size_t size,int flags)739 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
740 size_t size, int flags)
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 if (sk->sk_prot->sendpage)
752 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
753 return sock_no_sendpage(sock, page, offset, size, flags);
754 }
755 EXPORT_SYMBOL(inet_sendpage);
756
inet_recvmsg(struct socket * sock,struct msghdr * msg,size_t size,int flags)757 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
758 int flags)
759 {
760 struct sock *sk = sock->sk;
761 int addr_len = 0;
762 int err;
763
764 sock_rps_record_flow(sk);
765
766 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
767 flags & ~MSG_DONTWAIT, &addr_len);
768 if (err >= 0)
769 msg->msg_namelen = addr_len;
770 return err;
771 }
772 EXPORT_SYMBOL(inet_recvmsg);
773
inet_shutdown(struct socket * sock,int how)774 int inet_shutdown(struct socket *sock, int how)
775 {
776 struct sock *sk = sock->sk;
777 int err = 0;
778
779 /* This should really check to make sure
780 * the socket is a TCP socket. (WHY AC...)
781 */
782 how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
783 1->2 bit 2 snds.
784 2->3 */
785 if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */
786 return -EINVAL;
787
788 lock_sock(sk);
789 if (sock->state == SS_CONNECTING) {
790 if ((1 << sk->sk_state) &
791 (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
792 sock->state = SS_DISCONNECTING;
793 else
794 sock->state = SS_CONNECTED;
795 }
796
797 switch (sk->sk_state) {
798 case TCP_CLOSE:
799 err = -ENOTCONN;
800 /* Hack to wake up other listeners, who can poll for
801 POLLHUP, even on eg. unconnected UDP sockets -- RR */
802 default:
803 sk->sk_shutdown |= how;
804 if (sk->sk_prot->shutdown)
805 sk->sk_prot->shutdown(sk, how);
806 break;
807
808 /* Remaining two branches are temporary solution for missing
809 * close() in multithreaded environment. It is _not_ a good idea,
810 * but we have no choice until close() is repaired at VFS level.
811 */
812 case TCP_LISTEN:
813 if (!(how & RCV_SHUTDOWN))
814 break;
815 /* Fall through */
816 case TCP_SYN_SENT:
817 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
818 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
819 break;
820 }
821
822 /* Wake up anyone sleeping in poll. */
823 sk->sk_state_change(sk);
824 release_sock(sk);
825 return err;
826 }
827 EXPORT_SYMBOL(inet_shutdown);
828
829 /*
830 * ioctl() calls you can issue on an INET socket. Most of these are
831 * device configuration and stuff and very rarely used. Some ioctls
832 * pass on to the socket itself.
833 *
834 * NOTE: I like the idea of a module for the config stuff. ie ifconfig
835 * loads the devconfigure module does its configuring and unloads it.
836 * There's a good 20K of config code hanging around the kernel.
837 */
838
inet_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)839 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
840 {
841 struct sock *sk = sock->sk;
842 int err = 0;
843 struct net *net = sock_net(sk);
844
845 switch (cmd) {
846 case SIOCGSTAMP:
847 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
848 break;
849 case SIOCGSTAMPNS:
850 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
851 break;
852 case SIOCADDRT:
853 case SIOCDELRT:
854 case SIOCRTMSG:
855 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
856 break;
857 case SIOCDARP:
858 case SIOCGARP:
859 case SIOCSARP:
860 err = arp_ioctl(net, cmd, (void __user *)arg);
861 break;
862 case SIOCGIFADDR:
863 case SIOCSIFADDR:
864 case SIOCGIFBRDADDR:
865 case SIOCSIFBRDADDR:
866 case SIOCGIFNETMASK:
867 case SIOCSIFNETMASK:
868 case SIOCGIFDSTADDR:
869 case SIOCSIFDSTADDR:
870 case SIOCSIFPFLAGS:
871 case SIOCGIFPFLAGS:
872 case SIOCSIFFLAGS:
873 err = devinet_ioctl(net, cmd, (void __user *)arg);
874 break;
875 default:
876 if (sk->sk_prot->ioctl)
877 err = sk->sk_prot->ioctl(sk, cmd, arg);
878 else
879 err = -ENOIOCTLCMD;
880 break;
881 }
882 return err;
883 }
884 EXPORT_SYMBOL(inet_ioctl);
885
886 #ifdef CONFIG_COMPAT
inet_compat_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)887 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
888 {
889 struct sock *sk = sock->sk;
890 int err = -ENOIOCTLCMD;
891
892 if (sk->sk_prot->compat_ioctl)
893 err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
894
895 return err;
896 }
897 #endif
898
899 const struct proto_ops inet_stream_ops = {
900 .family = PF_INET,
901 .owner = THIS_MODULE,
902 .release = inet_release,
903 .bind = inet_bind,
904 .connect = inet_stream_connect,
905 .socketpair = sock_no_socketpair,
906 .accept = inet_accept,
907 .getname = inet_getname,
908 .poll = tcp_poll,
909 .ioctl = inet_ioctl,
910 .listen = inet_listen,
911 .shutdown = inet_shutdown,
912 .setsockopt = sock_common_setsockopt,
913 .getsockopt = sock_common_getsockopt,
914 .sendmsg = inet_sendmsg,
915 .recvmsg = inet_recvmsg,
916 .mmap = sock_no_mmap,
917 .sendpage = inet_sendpage,
918 .splice_read = tcp_splice_read,
919 #ifdef CONFIG_COMPAT
920 .compat_setsockopt = compat_sock_common_setsockopt,
921 .compat_getsockopt = compat_sock_common_getsockopt,
922 .compat_ioctl = inet_compat_ioctl,
923 #endif
924 };
925 EXPORT_SYMBOL(inet_stream_ops);
926
927 const struct proto_ops inet_dgram_ops = {
928 .family = PF_INET,
929 .owner = THIS_MODULE,
930 .release = inet_release,
931 .bind = inet_bind,
932 .connect = inet_dgram_connect,
933 .socketpair = sock_no_socketpair,
934 .accept = sock_no_accept,
935 .getname = inet_getname,
936 .poll = udp_poll,
937 .ioctl = inet_ioctl,
938 .listen = sock_no_listen,
939 .shutdown = inet_shutdown,
940 .setsockopt = sock_common_setsockopt,
941 .getsockopt = sock_common_getsockopt,
942 .sendmsg = inet_sendmsg,
943 .recvmsg = inet_recvmsg,
944 .mmap = sock_no_mmap,
945 .sendpage = inet_sendpage,
946 #ifdef CONFIG_COMPAT
947 .compat_setsockopt = compat_sock_common_setsockopt,
948 .compat_getsockopt = compat_sock_common_getsockopt,
949 .compat_ioctl = inet_compat_ioctl,
950 #endif
951 };
952 EXPORT_SYMBOL(inet_dgram_ops);
953
954 /*
955 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
956 * udp_poll
957 */
958 static const struct proto_ops inet_sockraw_ops = {
959 .family = PF_INET,
960 .owner = THIS_MODULE,
961 .release = inet_release,
962 .bind = inet_bind,
963 .connect = inet_dgram_connect,
964 .socketpair = sock_no_socketpair,
965 .accept = sock_no_accept,
966 .getname = inet_getname,
967 .poll = datagram_poll,
968 .ioctl = inet_ioctl,
969 .listen = sock_no_listen,
970 .shutdown = inet_shutdown,
971 .setsockopt = sock_common_setsockopt,
972 .getsockopt = sock_common_getsockopt,
973 .sendmsg = inet_sendmsg,
974 .recvmsg = inet_recvmsg,
975 .mmap = sock_no_mmap,
976 .sendpage = inet_sendpage,
977 #ifdef CONFIG_COMPAT
978 .compat_setsockopt = compat_sock_common_setsockopt,
979 .compat_getsockopt = compat_sock_common_getsockopt,
980 .compat_ioctl = inet_compat_ioctl,
981 #endif
982 };
983
984 static const struct net_proto_family inet_family_ops = {
985 .family = PF_INET,
986 .create = inet_create,
987 .owner = THIS_MODULE,
988 };
989
990 /* Upon startup we insert all the elements in inetsw_array[] into
991 * the linked list inetsw.
992 */
993 static struct inet_protosw inetsw_array[] =
994 {
995 {
996 .type = SOCK_STREAM,
997 .protocol = IPPROTO_TCP,
998 .prot = &tcp_prot,
999 .ops = &inet_stream_ops,
1000 .flags = INET_PROTOSW_PERMANENT |
1001 INET_PROTOSW_ICSK,
1002 },
1003
1004 {
1005 .type = SOCK_DGRAM,
1006 .protocol = IPPROTO_UDP,
1007 .prot = &udp_prot,
1008 .ops = &inet_dgram_ops,
1009 .flags = INET_PROTOSW_PERMANENT,
1010 },
1011
1012 {
1013 .type = SOCK_DGRAM,
1014 .protocol = IPPROTO_ICMP,
1015 .prot = &ping_prot,
1016 .ops = &inet_dgram_ops,
1017 .flags = INET_PROTOSW_REUSE,
1018 },
1019
1020 {
1021 .type = SOCK_RAW,
1022 .protocol = IPPROTO_IP, /* wild card */
1023 .prot = &raw_prot,
1024 .ops = &inet_sockraw_ops,
1025 .flags = INET_PROTOSW_REUSE,
1026 }
1027 };
1028
1029 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1030
inet_register_protosw(struct inet_protosw * p)1031 void inet_register_protosw(struct inet_protosw *p)
1032 {
1033 struct list_head *lh;
1034 struct inet_protosw *answer;
1035 int protocol = p->protocol;
1036 struct list_head *last_perm;
1037
1038 spin_lock_bh(&inetsw_lock);
1039
1040 if (p->type >= SOCK_MAX)
1041 goto out_illegal;
1042
1043 /* If we are trying to override a permanent protocol, bail. */
1044 answer = NULL;
1045 last_perm = &inetsw[p->type];
1046 list_for_each(lh, &inetsw[p->type]) {
1047 answer = list_entry(lh, struct inet_protosw, list);
1048
1049 /* Check only the non-wild match. */
1050 if (INET_PROTOSW_PERMANENT & answer->flags) {
1051 if (protocol == answer->protocol)
1052 break;
1053 last_perm = lh;
1054 }
1055
1056 answer = NULL;
1057 }
1058 if (answer)
1059 goto out_permanent;
1060
1061 /* Add the new entry after the last permanent entry if any, so that
1062 * the new entry does not override a permanent entry when matched with
1063 * a wild-card protocol. But it is allowed to override any existing
1064 * non-permanent entry. This means that when we remove this entry, the
1065 * system automatically returns to the old behavior.
1066 */
1067 list_add_rcu(&p->list, last_perm);
1068 out:
1069 spin_unlock_bh(&inetsw_lock);
1070
1071 return;
1072
1073 out_permanent:
1074 pr_err("Attempt to override permanent protocol %d\n", protocol);
1075 goto out;
1076
1077 out_illegal:
1078 pr_err("Ignoring attempt to register invalid socket type %d\n",
1079 p->type);
1080 goto out;
1081 }
1082 EXPORT_SYMBOL(inet_register_protosw);
1083
inet_unregister_protosw(struct inet_protosw * p)1084 void inet_unregister_protosw(struct inet_protosw *p)
1085 {
1086 if (INET_PROTOSW_PERMANENT & p->flags) {
1087 pr_err("Attempt to unregister permanent protocol %d\n",
1088 p->protocol);
1089 } else {
1090 spin_lock_bh(&inetsw_lock);
1091 list_del_rcu(&p->list);
1092 spin_unlock_bh(&inetsw_lock);
1093
1094 synchronize_net();
1095 }
1096 }
1097 EXPORT_SYMBOL(inet_unregister_protosw);
1098
1099 /*
1100 * Shall we try to damage output packets if routing dev changes?
1101 */
1102
1103 int sysctl_ip_dynaddr __read_mostly;
1104
inet_sk_reselect_saddr(struct sock * sk)1105 static int inet_sk_reselect_saddr(struct sock *sk)
1106 {
1107 struct inet_sock *inet = inet_sk(sk);
1108 __be32 old_saddr = inet->inet_saddr;
1109 __be32 daddr = inet->inet_daddr;
1110 struct flowi4 *fl4;
1111 struct rtable *rt;
1112 __be32 new_saddr;
1113 struct ip_options_rcu *inet_opt;
1114
1115 inet_opt = rcu_dereference_protected(inet->inet_opt,
1116 sock_owned_by_user(sk));
1117 if (inet_opt && inet_opt->opt.srr)
1118 daddr = inet_opt->opt.faddr;
1119
1120 /* Query new route. */
1121 fl4 = &inet->cork.fl.u.ip4;
1122 rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1123 sk->sk_bound_dev_if, sk->sk_protocol,
1124 inet->inet_sport, inet->inet_dport, sk);
1125 if (IS_ERR(rt))
1126 return PTR_ERR(rt);
1127
1128 sk_setup_caps(sk, &rt->dst);
1129
1130 new_saddr = fl4->saddr;
1131
1132 if (new_saddr == old_saddr)
1133 return 0;
1134
1135 if (sysctl_ip_dynaddr > 1) {
1136 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1137 __func__, &old_saddr, &new_saddr);
1138 }
1139
1140 inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1141
1142 /*
1143 * XXX The only one ugly spot where we need to
1144 * XXX really change the sockets identity after
1145 * XXX it has entered the hashes. -DaveM
1146 *
1147 * Besides that, it does not check for connection
1148 * uniqueness. Wait for troubles.
1149 */
1150 __sk_prot_rehash(sk);
1151 return 0;
1152 }
1153
inet_sk_rebuild_header(struct sock * sk)1154 int inet_sk_rebuild_header(struct sock *sk)
1155 {
1156 struct inet_sock *inet = inet_sk(sk);
1157 struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1158 __be32 daddr;
1159 struct ip_options_rcu *inet_opt;
1160 struct flowi4 *fl4;
1161 int err;
1162
1163 /* Route is OK, nothing to do. */
1164 if (rt)
1165 return 0;
1166
1167 /* Reroute. */
1168 rcu_read_lock();
1169 inet_opt = rcu_dereference(inet->inet_opt);
1170 daddr = inet->inet_daddr;
1171 if (inet_opt && inet_opt->opt.srr)
1172 daddr = inet_opt->opt.faddr;
1173 rcu_read_unlock();
1174 fl4 = &inet->cork.fl.u.ip4;
1175 rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1176 inet->inet_dport, inet->inet_sport,
1177 sk->sk_protocol, RT_CONN_FLAGS(sk),
1178 sk->sk_bound_dev_if);
1179 if (!IS_ERR(rt)) {
1180 err = 0;
1181 sk_setup_caps(sk, &rt->dst);
1182 } else {
1183 err = PTR_ERR(rt);
1184
1185 /* Routing failed... */
1186 sk->sk_route_caps = 0;
1187 /*
1188 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1189 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1190 */
1191 if (!sysctl_ip_dynaddr ||
1192 sk->sk_state != TCP_SYN_SENT ||
1193 (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1194 (err = inet_sk_reselect_saddr(sk)) != 0)
1195 sk->sk_err_soft = -err;
1196 }
1197
1198 return err;
1199 }
1200 EXPORT_SYMBOL(inet_sk_rebuild_header);
1201
inet_gso_segment(struct sk_buff * skb,netdev_features_t features)1202 static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1203 netdev_features_t features)
1204 {
1205 struct sk_buff *segs = ERR_PTR(-EINVAL);
1206 const struct net_offload *ops;
1207 unsigned int offset = 0;
1208 bool udpfrag, encap;
1209 struct iphdr *iph;
1210 int proto;
1211 int nhoff;
1212 int ihl;
1213 int id;
1214
1215 if (unlikely(skb_shinfo(skb)->gso_type &
1216 ~(SKB_GSO_TCPV4 |
1217 SKB_GSO_UDP |
1218 SKB_GSO_DODGY |
1219 SKB_GSO_TCP_ECN |
1220 SKB_GSO_GRE |
1221 SKB_GSO_GRE_CSUM |
1222 SKB_GSO_IPIP |
1223 SKB_GSO_SIT |
1224 SKB_GSO_TCPV6 |
1225 SKB_GSO_UDP_TUNNEL |
1226 SKB_GSO_UDP_TUNNEL_CSUM |
1227 SKB_GSO_TUNNEL_REMCSUM |
1228 0)))
1229 goto out;
1230
1231 skb_reset_network_header(skb);
1232 nhoff = skb_network_header(skb) - skb_mac_header(skb);
1233 if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1234 goto out;
1235
1236 iph = ip_hdr(skb);
1237 ihl = iph->ihl * 4;
1238 if (ihl < sizeof(*iph))
1239 goto out;
1240
1241 id = ntohs(iph->id);
1242 proto = iph->protocol;
1243
1244 /* Warning: after this point, iph might be no longer valid */
1245 if (unlikely(!pskb_may_pull(skb, ihl)))
1246 goto out;
1247 __skb_pull(skb, ihl);
1248
1249 encap = SKB_GSO_CB(skb)->encap_level > 0;
1250 if (encap)
1251 features &= skb->dev->hw_enc_features;
1252 SKB_GSO_CB(skb)->encap_level += ihl;
1253
1254 skb_reset_transport_header(skb);
1255
1256 segs = ERR_PTR(-EPROTONOSUPPORT);
1257
1258 if (skb->encapsulation &&
1259 skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP))
1260 udpfrag = proto == IPPROTO_UDP && encap;
1261 else
1262 udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;
1263
1264 ops = rcu_dereference(inet_offloads[proto]);
1265 if (likely(ops && ops->callbacks.gso_segment))
1266 segs = ops->callbacks.gso_segment(skb, features);
1267
1268 if (IS_ERR_OR_NULL(segs))
1269 goto out;
1270
1271 skb = segs;
1272 do {
1273 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1274 if (udpfrag) {
1275 iph->id = htons(id);
1276 iph->frag_off = htons(offset >> 3);
1277 if (skb->next)
1278 iph->frag_off |= htons(IP_MF);
1279 offset += skb->len - nhoff - ihl;
1280 } else {
1281 iph->id = htons(id++);
1282 }
1283 iph->tot_len = htons(skb->len - nhoff);
1284 ip_send_check(iph);
1285 if (encap)
1286 skb_reset_inner_headers(skb);
1287 skb->network_header = (u8 *)iph - skb->head;
1288 } while ((skb = skb->next));
1289
1290 out:
1291 return segs;
1292 }
1293
inet_gro_receive(struct sk_buff ** head,struct sk_buff * skb)1294 static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1295 struct sk_buff *skb)
1296 {
1297 const struct net_offload *ops;
1298 struct sk_buff **pp = NULL;
1299 struct sk_buff *p;
1300 const struct iphdr *iph;
1301 unsigned int hlen;
1302 unsigned int off;
1303 unsigned int id;
1304 int flush = 1;
1305 int proto;
1306
1307 off = skb_gro_offset(skb);
1308 hlen = off + sizeof(*iph);
1309 iph = skb_gro_header_fast(skb, off);
1310 if (skb_gro_header_hard(skb, hlen)) {
1311 iph = skb_gro_header_slow(skb, hlen, off);
1312 if (unlikely(!iph))
1313 goto out;
1314 }
1315
1316 proto = iph->protocol;
1317
1318 rcu_read_lock();
1319 ops = rcu_dereference(inet_offloads[proto]);
1320 if (!ops || !ops->callbacks.gro_receive)
1321 goto out_unlock;
1322
1323 if (*(u8 *)iph != 0x45)
1324 goto out_unlock;
1325
1326 if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1327 goto out_unlock;
1328
1329 id = ntohl(*(__be32 *)&iph->id);
1330 flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
1331 id >>= 16;
1332
1333 for (p = *head; p; p = p->next) {
1334 struct iphdr *iph2;
1335
1336 if (!NAPI_GRO_CB(p)->same_flow)
1337 continue;
1338
1339 iph2 = (struct iphdr *)(p->data + off);
1340 /* The above works because, with the exception of the top
1341 * (inner most) layer, we only aggregate pkts with the same
1342 * hdr length so all the hdrs we'll need to verify will start
1343 * at the same offset.
1344 */
1345 if ((iph->protocol ^ iph2->protocol) |
1346 ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1347 ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1348 NAPI_GRO_CB(p)->same_flow = 0;
1349 continue;
1350 }
1351
1352 /* All fields must match except length and checksum. */
1353 NAPI_GRO_CB(p)->flush |=
1354 (iph->ttl ^ iph2->ttl) |
1355 (iph->tos ^ iph2->tos) |
1356 ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF));
1357
1358 /* Save the IP ID check to be included later when we get to
1359 * the transport layer so only the inner most IP ID is checked.
1360 * This is because some GSO/TSO implementations do not
1361 * correctly increment the IP ID for the outer hdrs.
1362 */
1363 NAPI_GRO_CB(p)->flush_id =
1364 ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1365 NAPI_GRO_CB(p)->flush |= flush;
1366 }
1367
1368 NAPI_GRO_CB(skb)->flush |= flush;
1369 skb_set_network_header(skb, off);
1370 /* The above will be needed by the transport layer if there is one
1371 * immediately following this IP hdr.
1372 */
1373
1374 /* Note : No need to call skb_gro_postpull_rcsum() here,
1375 * as we already checked checksum over ipv4 header was 0
1376 */
1377 skb_gro_pull(skb, sizeof(*iph));
1378 skb_set_transport_header(skb, skb_gro_offset(skb));
1379
1380 pp = ops->callbacks.gro_receive(head, skb);
1381
1382 out_unlock:
1383 rcu_read_unlock();
1384
1385 out:
1386 NAPI_GRO_CB(skb)->flush |= flush;
1387
1388 return pp;
1389 }
1390
inet_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)1391 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
1392 {
1393 if (sk->sk_family == AF_INET)
1394 return ip_recv_error(sk, msg, len, addr_len);
1395 #if IS_ENABLED(CONFIG_IPV6)
1396 if (sk->sk_family == AF_INET6)
1397 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
1398 #endif
1399 return -EINVAL;
1400 }
1401
inet_gro_complete(struct sk_buff * skb,int nhoff)1402 static int inet_gro_complete(struct sk_buff *skb, int nhoff)
1403 {
1404 __be16 newlen = htons(skb->len - nhoff);
1405 struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1406 const struct net_offload *ops;
1407 int proto = iph->protocol;
1408 int err = -ENOSYS;
1409
1410 if (skb->encapsulation)
1411 skb_set_inner_network_header(skb, nhoff);
1412
1413 csum_replace2(&iph->check, iph->tot_len, newlen);
1414 iph->tot_len = newlen;
1415
1416 rcu_read_lock();
1417 ops = rcu_dereference(inet_offloads[proto]);
1418 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1419 goto out_unlock;
1420
1421 /* Only need to add sizeof(*iph) to get to the next hdr below
1422 * because any hdr with option will have been flushed in
1423 * inet_gro_receive().
1424 */
1425 err = ops->callbacks.gro_complete(skb, nhoff + sizeof(*iph));
1426
1427 out_unlock:
1428 rcu_read_unlock();
1429
1430 return err;
1431 }
1432
inet_ctl_sock_create(struct sock ** sk,unsigned short family,unsigned short type,unsigned char protocol,struct net * net)1433 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1434 unsigned short type, unsigned char protocol,
1435 struct net *net)
1436 {
1437 struct socket *sock;
1438 int rc = sock_create_kern(family, type, protocol, &sock);
1439
1440 if (rc == 0) {
1441 *sk = sock->sk;
1442 (*sk)->sk_allocation = GFP_ATOMIC;
1443 /*
1444 * Unhash it so that IP input processing does not even see it,
1445 * we do not wish this socket to see incoming packets.
1446 */
1447 (*sk)->sk_prot->unhash(*sk);
1448
1449 sk_change_net(*sk, net);
1450 }
1451 return rc;
1452 }
1453 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1454
snmp_fold_field(void __percpu * mib,int offt)1455 unsigned long snmp_fold_field(void __percpu *mib, int offt)
1456 {
1457 unsigned long res = 0;
1458 int i;
1459
1460 for_each_possible_cpu(i)
1461 res += *(((unsigned long *) per_cpu_ptr(mib, i)) + offt);
1462 return res;
1463 }
1464 EXPORT_SYMBOL_GPL(snmp_fold_field);
1465
1466 #if BITS_PER_LONG==32
1467
snmp_fold_field64(void __percpu * mib,int offt,size_t syncp_offset)1468 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1469 {
1470 u64 res = 0;
1471 int cpu;
1472
1473 for_each_possible_cpu(cpu) {
1474 void *bhptr;
1475 struct u64_stats_sync *syncp;
1476 u64 v;
1477 unsigned int start;
1478
1479 bhptr = per_cpu_ptr(mib, cpu);
1480 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1481 do {
1482 start = u64_stats_fetch_begin_irq(syncp);
1483 v = *(((u64 *) bhptr) + offt);
1484 } while (u64_stats_fetch_retry_irq(syncp, start));
1485
1486 res += v;
1487 }
1488 return res;
1489 }
1490 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1491 #endif
1492
1493 #ifdef CONFIG_IP_MULTICAST
1494 static const struct net_protocol igmp_protocol = {
1495 .handler = igmp_rcv,
1496 .netns_ok = 1,
1497 };
1498 #endif
1499
1500 static const struct net_protocol tcp_protocol = {
1501 .early_demux = tcp_v4_early_demux,
1502 .handler = tcp_v4_rcv,
1503 .err_handler = tcp_v4_err,
1504 .no_policy = 1,
1505 .netns_ok = 1,
1506 .icmp_strict_tag_validation = 1,
1507 };
1508
1509 static const struct net_protocol udp_protocol = {
1510 .early_demux = udp_v4_early_demux,
1511 .handler = udp_rcv,
1512 .err_handler = udp_err,
1513 .no_policy = 1,
1514 .netns_ok = 1,
1515 };
1516
1517 static const struct net_protocol icmp_protocol = {
1518 .handler = icmp_rcv,
1519 .err_handler = icmp_err,
1520 .no_policy = 1,
1521 .netns_ok = 1,
1522 };
1523
ipv4_mib_init_net(struct net * net)1524 static __net_init int ipv4_mib_init_net(struct net *net)
1525 {
1526 int i;
1527
1528 net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1529 if (!net->mib.tcp_statistics)
1530 goto err_tcp_mib;
1531 net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1532 if (!net->mib.ip_statistics)
1533 goto err_ip_mib;
1534
1535 for_each_possible_cpu(i) {
1536 struct ipstats_mib *af_inet_stats;
1537 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1538 u64_stats_init(&af_inet_stats->syncp);
1539 }
1540
1541 net->mib.net_statistics = alloc_percpu(struct linux_mib);
1542 if (!net->mib.net_statistics)
1543 goto err_net_mib;
1544 net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1545 if (!net->mib.udp_statistics)
1546 goto err_udp_mib;
1547 net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1548 if (!net->mib.udplite_statistics)
1549 goto err_udplite_mib;
1550 net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1551 if (!net->mib.icmp_statistics)
1552 goto err_icmp_mib;
1553 net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1554 GFP_KERNEL);
1555 if (!net->mib.icmpmsg_statistics)
1556 goto err_icmpmsg_mib;
1557
1558 tcp_mib_init(net);
1559 return 0;
1560
1561 err_icmpmsg_mib:
1562 free_percpu(net->mib.icmp_statistics);
1563 err_icmp_mib:
1564 free_percpu(net->mib.udplite_statistics);
1565 err_udplite_mib:
1566 free_percpu(net->mib.udp_statistics);
1567 err_udp_mib:
1568 free_percpu(net->mib.net_statistics);
1569 err_net_mib:
1570 free_percpu(net->mib.ip_statistics);
1571 err_ip_mib:
1572 free_percpu(net->mib.tcp_statistics);
1573 err_tcp_mib:
1574 return -ENOMEM;
1575 }
1576
ipv4_mib_exit_net(struct net * net)1577 static __net_exit void ipv4_mib_exit_net(struct net *net)
1578 {
1579 kfree(net->mib.icmpmsg_statistics);
1580 free_percpu(net->mib.icmp_statistics);
1581 free_percpu(net->mib.udplite_statistics);
1582 free_percpu(net->mib.udp_statistics);
1583 free_percpu(net->mib.net_statistics);
1584 free_percpu(net->mib.ip_statistics);
1585 free_percpu(net->mib.tcp_statistics);
1586 }
1587
1588 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1589 .init = ipv4_mib_init_net,
1590 .exit = ipv4_mib_exit_net,
1591 };
1592
init_ipv4_mibs(void)1593 static int __init init_ipv4_mibs(void)
1594 {
1595 return register_pernet_subsys(&ipv4_mib_ops);
1596 }
1597
inet_init_net(struct net * net)1598 static __net_init int inet_init_net(struct net *net)
1599 {
1600 /*
1601 * Set defaults for local port range
1602 */
1603 seqlock_init(&net->ipv4.ip_local_ports.lock);
1604 net->ipv4.ip_local_ports.range[0] = 32768;
1605 net->ipv4.ip_local_ports.range[1] = 61000;
1606
1607 seqlock_init(&net->ipv4.ping_group_range.lock);
1608 /*
1609 * Sane defaults - nobody may create ping sockets.
1610 * Boot scripts should set this to distro-specific group.
1611 */
1612 net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1);
1613 net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0);
1614 return 0;
1615 }
1616
inet_exit_net(struct net * net)1617 static __net_exit void inet_exit_net(struct net *net)
1618 {
1619 }
1620
1621 static __net_initdata struct pernet_operations af_inet_ops = {
1622 .init = inet_init_net,
1623 .exit = inet_exit_net,
1624 };
1625
init_inet_pernet_ops(void)1626 static int __init init_inet_pernet_ops(void)
1627 {
1628 return register_pernet_subsys(&af_inet_ops);
1629 }
1630
1631 static int ipv4_proc_init(void);
1632
1633 /*
1634 * IP protocol layer initialiser
1635 */
1636
1637 static struct packet_offload ip_packet_offload __read_mostly = {
1638 .type = cpu_to_be16(ETH_P_IP),
1639 .callbacks = {
1640 .gso_segment = inet_gso_segment,
1641 .gro_receive = inet_gro_receive,
1642 .gro_complete = inet_gro_complete,
1643 },
1644 };
1645
1646 static const struct net_offload ipip_offload = {
1647 .callbacks = {
1648 .gso_segment = inet_gso_segment,
1649 .gro_receive = inet_gro_receive,
1650 .gro_complete = inet_gro_complete,
1651 },
1652 };
1653
ipv4_offload_init(void)1654 static int __init ipv4_offload_init(void)
1655 {
1656 /*
1657 * Add offloads
1658 */
1659 if (udpv4_offload_init() < 0)
1660 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1661 if (tcpv4_offload_init() < 0)
1662 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1663
1664 dev_add_offload(&ip_packet_offload);
1665 inet_add_offload(&ipip_offload, IPPROTO_IPIP);
1666 return 0;
1667 }
1668
1669 fs_initcall(ipv4_offload_init);
1670
1671 static struct packet_type ip_packet_type __read_mostly = {
1672 .type = cpu_to_be16(ETH_P_IP),
1673 .func = ip_rcv,
1674 };
1675
inet_init(void)1676 static int __init inet_init(void)
1677 {
1678 struct inet_protosw *q;
1679 struct list_head *r;
1680 int rc = -EINVAL;
1681
1682 sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
1683
1684 rc = proto_register(&tcp_prot, 1);
1685 if (rc)
1686 goto out;
1687
1688 rc = proto_register(&udp_prot, 1);
1689 if (rc)
1690 goto out_unregister_tcp_proto;
1691
1692 rc = proto_register(&raw_prot, 1);
1693 if (rc)
1694 goto out_unregister_udp_proto;
1695
1696 rc = proto_register(&ping_prot, 1);
1697 if (rc)
1698 goto out_unregister_raw_proto;
1699
1700 /*
1701 * Tell SOCKET that we are alive...
1702 */
1703
1704 (void)sock_register(&inet_family_ops);
1705
1706 #ifdef CONFIG_SYSCTL
1707 ip_static_sysctl_init();
1708 #endif
1709
1710 /*
1711 * Add all the base protocols.
1712 */
1713
1714 if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1715 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1716 if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1717 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1718 if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1719 pr_crit("%s: Cannot add TCP protocol\n", __func__);
1720 #ifdef CONFIG_IP_MULTICAST
1721 if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1722 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1723 #endif
1724
1725 /* Register the socket-side information for inet_create. */
1726 for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1727 INIT_LIST_HEAD(r);
1728
1729 for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1730 inet_register_protosw(q);
1731
1732 /*
1733 * Set the ARP module up
1734 */
1735
1736 arp_init();
1737
1738 /*
1739 * Set the IP module up
1740 */
1741
1742 ip_init();
1743
1744 tcp_v4_init();
1745
1746 /* Setup TCP slab cache for open requests. */
1747 tcp_init();
1748
1749 /* Setup UDP memory threshold */
1750 udp_init();
1751
1752 /* Add UDP-Lite (RFC 3828) */
1753 udplite4_register();
1754
1755 ping_init();
1756
1757 /*
1758 * Set the ICMP layer up
1759 */
1760
1761 if (icmp_init() < 0)
1762 panic("Failed to create the ICMP control socket.\n");
1763
1764 /*
1765 * Initialise the multicast router
1766 */
1767 #if defined(CONFIG_IP_MROUTE)
1768 if (ip_mr_init())
1769 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
1770 #endif
1771
1772 if (init_inet_pernet_ops())
1773 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
1774 /*
1775 * Initialise per-cpu ipv4 mibs
1776 */
1777
1778 if (init_ipv4_mibs())
1779 pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
1780
1781 ipv4_proc_init();
1782
1783 ipfrag_init();
1784
1785 dev_add_pack(&ip_packet_type);
1786
1787 rc = 0;
1788 out:
1789 return rc;
1790 out_unregister_raw_proto:
1791 proto_unregister(&raw_prot);
1792 out_unregister_udp_proto:
1793 proto_unregister(&udp_prot);
1794 out_unregister_tcp_proto:
1795 proto_unregister(&tcp_prot);
1796 goto out;
1797 }
1798
1799 fs_initcall(inet_init);
1800
1801 /* ------------------------------------------------------------------------ */
1802
1803 #ifdef CONFIG_PROC_FS
ipv4_proc_init(void)1804 static int __init ipv4_proc_init(void)
1805 {
1806 int rc = 0;
1807
1808 if (raw_proc_init())
1809 goto out_raw;
1810 if (tcp4_proc_init())
1811 goto out_tcp;
1812 if (udp4_proc_init())
1813 goto out_udp;
1814 if (ping_proc_init())
1815 goto out_ping;
1816 if (ip_misc_proc_init())
1817 goto out_misc;
1818 out:
1819 return rc;
1820 out_misc:
1821 ping_proc_exit();
1822 out_ping:
1823 udp4_proc_exit();
1824 out_udp:
1825 tcp4_proc_exit();
1826 out_tcp:
1827 raw_proc_exit();
1828 out_raw:
1829 rc = -ENOMEM;
1830 goto out;
1831 }
1832
1833 #else /* CONFIG_PROC_FS */
ipv4_proc_init(void)1834 static int __init ipv4_proc_init(void)
1835 {
1836 return 0;
1837 }
1838 #endif /* CONFIG_PROC_FS */
1839
1840 MODULE_ALIAS_NETPROTO(PF_INET);
1841
1842