net: reserve ports for applications using fixed port numbers
[linux-2.6.git] / net / ipv4 / af_inet.c
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 #include <linux/err.h>
69 #include <linux/errno.h>
70 #include <linux/types.h>
71 #include <linux/socket.h>
72 #include <linux/in.h>
73 #include <linux/kernel.h>
74 #include <linux/module.h>
75 #include <linux/sched.h>
76 #include <linux/timer.h>
77 #include <linux/string.h>
78 #include <linux/sockios.h>
79 #include <linux/net.h>
80 #include <linux/capability.h>
81 #include <linux/fcntl.h>
82 #include <linux/mm.h>
83 #include <linux/interrupt.h>
84 #include <linux/stat.h>
85 #include <linux/init.h>
86 #include <linux/poll.h>
87 #include <linux/netfilter_ipv4.h>
88 #include <linux/random.h>
89 #include <linux/slab.h>
90
91 #include <asm/uaccess.h>
92 #include <asm/system.h>
93
94 #include <linux/inet.h>
95 #include <linux/igmp.h>
96 #include <linux/inetdevice.h>
97 #include <linux/netdevice.h>
98 #include <net/checksum.h>
99 #include <net/ip.h>
100 #include <net/protocol.h>
101 #include <net/arp.h>
102 #include <net/route.h>
103 #include <net/ip_fib.h>
104 #include <net/inet_connection_sock.h>
105 #include <net/tcp.h>
106 #include <net/udp.h>
107 #include <net/udplite.h>
108 #include <linux/skbuff.h>
109 #include <net/sock.h>
110 #include <net/raw.h>
111 #include <net/icmp.h>
112 #include <net/ipip.h>
113 #include <net/inet_common.h>
114 #include <net/xfrm.h>
115 #include <net/net_namespace.h>
116 #ifdef CONFIG_IP_MROUTE
117 #include <linux/mroute.h>
118 #endif
119
120
121 /* The inetsw table contains everything that inet_create needs to
122  * build a new socket.
123  */
124 static struct list_head inetsw[SOCK_MAX];
125 static DEFINE_SPINLOCK(inetsw_lock);
126
127 struct ipv4_config ipv4_config;
128 EXPORT_SYMBOL(ipv4_config);
129
130 /* New destruction routine */
131
132 void inet_sock_destruct(struct sock *sk)
133 {
134         struct inet_sock *inet = inet_sk(sk);
135
136         __skb_queue_purge(&sk->sk_receive_queue);
137         __skb_queue_purge(&sk->sk_error_queue);
138
139         sk_mem_reclaim(sk);
140
141         if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
142                 pr_err("Attempt to release TCP socket in state %d %p\n",
143                        sk->sk_state, sk);
144                 return;
145         }
146         if (!sock_flag(sk, SOCK_DEAD)) {
147                 pr_err("Attempt to release alive inet socket %p\n", sk);
148                 return;
149         }
150
151         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
152         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
153         WARN_ON(sk->sk_wmem_queued);
154         WARN_ON(sk->sk_forward_alloc);
155
156         kfree(inet->opt);
157         dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
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
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  */
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                 err = inet_csk_listen_start(sk, backlog);
213                 if (err)
214                         goto out;
215         }
216         sk->sk_max_ack_backlog = backlog;
217         err = 0;
218
219 out:
220         release_sock(sk);
221         return err;
222 }
223 EXPORT_SYMBOL(inet_listen);
224
225 u32 inet_ehash_secret __read_mostly;
226 EXPORT_SYMBOL(inet_ehash_secret);
227
228 /*
229  * inet_ehash_secret must be set exactly once
230  * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
231  */
232 void build_ehash_secret(void)
233 {
234         u32 rnd;
235         do {
236                 get_random_bytes(&rnd, sizeof(rnd));
237         } while (rnd == 0);
238         spin_lock_bh(&inetsw_lock);
239         if (!inet_ehash_secret)
240                 inet_ehash_secret = rnd;
241         spin_unlock_bh(&inetsw_lock);
242 }
243 EXPORT_SYMBOL(build_ehash_secret);
244
245 static inline int inet_netns_ok(struct net *net, int protocol)
246 {
247         int hash;
248         const struct net_protocol *ipprot;
249
250         if (net_eq(net, &init_net))
251                 return 1;
252
253         hash = protocol & (MAX_INET_PROTOS - 1);
254         ipprot = rcu_dereference(inet_protos[hash]);
255
256         if (ipprot == NULL)
257                 /* raw IP is OK */
258                 return 1;
259         return ipprot->netns_ok;
260 }
261
262 /*
263  *      Create an inet socket.
264  */
265
266 static int inet_create(struct net *net, struct socket *sock, int protocol,
267                        int kern)
268 {
269         struct sock *sk;
270         struct inet_protosw *answer;
271         struct inet_sock *inet;
272         struct proto *answer_prot;
273         unsigned char answer_flags;
274         char answer_no_check;
275         int try_loading_module = 0;
276         int err;
277
278         if (unlikely(!inet_ehash_secret))
279                 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
280                         build_ehash_secret();
281
282         sock->state = SS_UNCONNECTED;
283
284         /* Look for the requested type/protocol pair. */
285 lookup_protocol:
286         err = -ESOCKTNOSUPPORT;
287         rcu_read_lock();
288         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
289
290                 err = 0;
291                 /* Check the non-wild match. */
292                 if (protocol == answer->protocol) {
293                         if (protocol != IPPROTO_IP)
294                                 break;
295                 } else {
296                         /* Check for the two wild cases. */
297                         if (IPPROTO_IP == protocol) {
298                                 protocol = answer->protocol;
299                                 break;
300                         }
301                         if (IPPROTO_IP == answer->protocol)
302                                 break;
303                 }
304                 err = -EPROTONOSUPPORT;
305         }
306
307         if (unlikely(err)) {
308                 if (try_loading_module < 2) {
309                         rcu_read_unlock();
310                         /*
311                          * Be more specific, e.g. net-pf-2-proto-132-type-1
312                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
313                          */
314                         if (++try_loading_module == 1)
315                                 request_module("net-pf-%d-proto-%d-type-%d",
316                                                PF_INET, protocol, sock->type);
317                         /*
318                          * Fall back to generic, e.g. net-pf-2-proto-132
319                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
320                          */
321                         else
322                                 request_module("net-pf-%d-proto-%d",
323                                                PF_INET, protocol);
324                         goto lookup_protocol;
325                 } else
326                         goto out_rcu_unlock;
327         }
328
329         err = -EPERM;
330         if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
331                 goto out_rcu_unlock;
332
333         err = -EAFNOSUPPORT;
334         if (!inet_netns_ok(net, protocol))
335                 goto out_rcu_unlock;
336
337         sock->ops = answer->ops;
338         answer_prot = answer->prot;
339         answer_no_check = answer->no_check;
340         answer_flags = answer->flags;
341         rcu_read_unlock();
342
343         WARN_ON(answer_prot->slab == NULL);
344
345         err = -ENOBUFS;
346         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
347         if (sk == NULL)
348                 goto out;
349
350         err = 0;
351         sk->sk_no_check = answer_no_check;
352         if (INET_PROTOSW_REUSE & answer_flags)
353                 sk->sk_reuse = 1;
354
355         inet = inet_sk(sk);
356         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
357
358         if (SOCK_RAW == sock->type) {
359                 inet->inet_num = protocol;
360                 if (IPPROTO_RAW == protocol)
361                         inet->hdrincl = 1;
362         }
363
364         if (ipv4_config.no_pmtu_disc)
365                 inet->pmtudisc = IP_PMTUDISC_DONT;
366         else
367                 inet->pmtudisc = IP_PMTUDISC_WANT;
368
369         inet->inet_id = 0;
370
371         sock_init_data(sock, sk);
372
373         sk->sk_destruct    = inet_sock_destruct;
374         sk->sk_protocol    = protocol;
375         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
376
377         inet->uc_ttl    = -1;
378         inet->mc_loop   = 1;
379         inet->mc_ttl    = 1;
380         inet->mc_all    = 1;
381         inet->mc_index  = 0;
382         inet->mc_list   = NULL;
383
384         sk_refcnt_debug_inc(sk);
385
386         if (inet->inet_num) {
387                 /* It assumes that any protocol which allows
388                  * the user to assign a number at socket
389                  * creation time automatically
390                  * shares.
391                  */
392                 inet->inet_sport = htons(inet->inet_num);
393                 /* Add to protocol hash chains. */
394                 sk->sk_prot->hash(sk);
395         }
396
397         if (sk->sk_prot->init) {
398                 err = sk->sk_prot->init(sk);
399                 if (err)
400                         sk_common_release(sk);
401         }
402 out:
403         return err;
404 out_rcu_unlock:
405         rcu_read_unlock();
406         goto out;
407 }
408
409
410 /*
411  *      The peer socket should always be NULL (or else). When we call this
412  *      function we are destroying the object and from then on nobody
413  *      should refer to it.
414  */
415 int inet_release(struct socket *sock)
416 {
417         struct sock *sk = sock->sk;
418
419         if (sk) {
420                 long timeout;
421
422                 sock_rps_reset_flow(sk);
423
424                 /* Applications forget to leave groups before exiting */
425                 ip_mc_drop_socket(sk);
426
427                 /* If linger is set, we don't return until the close
428                  * is complete.  Otherwise we return immediately. The
429                  * actually closing is done the same either way.
430                  *
431                  * If the close is due to the process exiting, we never
432                  * linger..
433                  */
434                 timeout = 0;
435                 if (sock_flag(sk, SOCK_LINGER) &&
436                     !(current->flags & PF_EXITING))
437                         timeout = sk->sk_lingertime;
438                 sock->sk = NULL;
439                 sk->sk_prot->close(sk, timeout);
440         }
441         return 0;
442 }
443 EXPORT_SYMBOL(inet_release);
444
445 /* It is off by default, see below. */
446 int sysctl_ip_nonlocal_bind __read_mostly;
447 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
448
449 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
450 {
451         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
452         struct sock *sk = sock->sk;
453         struct inet_sock *inet = inet_sk(sk);
454         unsigned short snum;
455         int chk_addr_ret;
456         int err;
457
458         /* If the socket has its own bind function then use it. (RAW) */
459         if (sk->sk_prot->bind) {
460                 err = sk->sk_prot->bind(sk, uaddr, addr_len);
461                 goto out;
462         }
463         err = -EINVAL;
464         if (addr_len < sizeof(struct sockaddr_in))
465                 goto out;
466
467         chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
468
469         /* Not specified by any standard per-se, however it breaks too
470          * many applications when removed.  It is unfortunate since
471          * allowing applications to make a non-local bind solves
472          * several problems with systems using dynamic addressing.
473          * (ie. your servers still start up even if your ISDN link
474          *  is temporarily down)
475          */
476         err = -EADDRNOTAVAIL;
477         if (!sysctl_ip_nonlocal_bind &&
478             !(inet->freebind || inet->transparent) &&
479             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
480             chk_addr_ret != RTN_LOCAL &&
481             chk_addr_ret != RTN_MULTICAST &&
482             chk_addr_ret != RTN_BROADCAST)
483                 goto out;
484
485         snum = ntohs(addr->sin_port);
486         err = -EACCES;
487         if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
488                 goto out;
489
490         /*      We keep a pair of addresses. rcv_saddr is the one
491          *      used by hash lookups, and saddr is used for transmit.
492          *
493          *      In the BSD API these are the same except where it
494          *      would be illegal to use them (multicast/broadcast) in
495          *      which case the sending device address is used.
496          */
497         lock_sock(sk);
498
499         /* Check these errors (active socket, double bind). */
500         err = -EINVAL;
501         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
502                 goto out_release_sock;
503
504         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
505         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
506                 inet->inet_saddr = 0;  /* Use device */
507
508         /* Make sure we are allowed to bind here. */
509         if (sk->sk_prot->get_port(sk, snum)) {
510                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
511                 err = -EADDRINUSE;
512                 goto out_release_sock;
513         }
514
515         if (inet->inet_rcv_saddr)
516                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
517         if (snum)
518                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
519         inet->inet_sport = htons(inet->inet_num);
520         inet->inet_daddr = 0;
521         inet->inet_dport = 0;
522         sk_dst_reset(sk);
523         err = 0;
524 out_release_sock:
525         release_sock(sk);
526 out:
527         return err;
528 }
529 EXPORT_SYMBOL(inet_bind);
530
531 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
532                        int addr_len, int flags)
533 {
534         struct sock *sk = sock->sk;
535
536         if (addr_len < sizeof(uaddr->sa_family))
537                 return -EINVAL;
538         if (uaddr->sa_family == AF_UNSPEC)
539                 return sk->sk_prot->disconnect(sk, flags);
540
541         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
542                 return -EAGAIN;
543         return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
544 }
545 EXPORT_SYMBOL(inet_dgram_connect);
546
547 static long inet_wait_for_connect(struct sock *sk, long timeo)
548 {
549         DEFINE_WAIT(wait);
550
551         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
552
553         /* Basic assumption: if someone sets sk->sk_err, he _must_
554          * change state of the socket from TCP_SYN_*.
555          * Connect() does not allow to get error notifications
556          * without closing the socket.
557          */
558         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
559                 release_sock(sk);
560                 timeo = schedule_timeout(timeo);
561                 lock_sock(sk);
562                 if (signal_pending(current) || !timeo)
563                         break;
564                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
565         }
566         finish_wait(sk_sleep(sk), &wait);
567         return timeo;
568 }
569
570 /*
571  *      Connect to a remote host. There is regrettably still a little
572  *      TCP 'magic' in here.
573  */
574 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
575                         int addr_len, int flags)
576 {
577         struct sock *sk = sock->sk;
578         int err;
579         long timeo;
580
581         if (addr_len < sizeof(uaddr->sa_family))
582                 return -EINVAL;
583
584         lock_sock(sk);
585
586         if (uaddr->sa_family == AF_UNSPEC) {
587                 err = sk->sk_prot->disconnect(sk, flags);
588                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
589                 goto out;
590         }
591
592         switch (sock->state) {
593         default:
594                 err = -EINVAL;
595                 goto out;
596         case SS_CONNECTED:
597                 err = -EISCONN;
598                 goto out;
599         case SS_CONNECTING:
600                 err = -EALREADY;
601                 /* Fall out of switch with err, set for this state */
602                 break;
603         case SS_UNCONNECTED:
604                 err = -EISCONN;
605                 if (sk->sk_state != TCP_CLOSE)
606                         goto out;
607
608                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
609                 if (err < 0)
610                         goto out;
611
612                 sock->state = SS_CONNECTING;
613
614                 /* Just entered SS_CONNECTING state; the only
615                  * difference is that return value in non-blocking
616                  * case is EINPROGRESS, rather than EALREADY.
617                  */
618                 err = -EINPROGRESS;
619                 break;
620         }
621
622         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
623
624         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
625                 /* Error code is set above */
626                 if (!timeo || !inet_wait_for_connect(sk, timeo))
627                         goto out;
628
629                 err = sock_intr_errno(timeo);
630                 if (signal_pending(current))
631                         goto out;
632         }
633
634         /* Connection was closed by RST, timeout, ICMP error
635          * or another process disconnected us.
636          */
637         if (sk->sk_state == TCP_CLOSE)
638                 goto sock_error;
639
640         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
641          * and error was received after socket entered established state.
642          * Hence, it is handled normally after connect() return successfully.
643          */
644
645         sock->state = SS_CONNECTED;
646         err = 0;
647 out:
648         release_sock(sk);
649         return err;
650
651 sock_error:
652         err = sock_error(sk) ? : -ECONNABORTED;
653         sock->state = SS_UNCONNECTED;
654         if (sk->sk_prot->disconnect(sk, flags))
655                 sock->state = SS_DISCONNECTING;
656         goto out;
657 }
658 EXPORT_SYMBOL(inet_stream_connect);
659
660 /*
661  *      Accept a pending connection. The TCP layer now gives BSD semantics.
662  */
663
664 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
665 {
666         struct sock *sk1 = sock->sk;
667         int err = -EINVAL;
668         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
669
670         if (!sk2)
671                 goto do_err;
672
673         lock_sock(sk2);
674
675         WARN_ON(!((1 << sk2->sk_state) &
676                   (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
677
678         sock_graft(sk2, newsock);
679
680         newsock->state = SS_CONNECTED;
681         err = 0;
682         release_sock(sk2);
683 do_err:
684         return err;
685 }
686 EXPORT_SYMBOL(inet_accept);
687
688
689 /*
690  *      This does both peername and sockname.
691  */
692 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
693                         int *uaddr_len, int peer)
694 {
695         struct sock *sk         = sock->sk;
696         struct inet_sock *inet  = inet_sk(sk);
697         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
698
699         sin->sin_family = AF_INET;
700         if (peer) {
701                 if (!inet->inet_dport ||
702                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
703                      peer == 1))
704                         return -ENOTCONN;
705                 sin->sin_port = inet->inet_dport;
706                 sin->sin_addr.s_addr = inet->inet_daddr;
707         } else {
708                 __be32 addr = inet->inet_rcv_saddr;
709                 if (!addr)
710                         addr = inet->inet_saddr;
711                 sin->sin_port = inet->inet_sport;
712                 sin->sin_addr.s_addr = addr;
713         }
714         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
715         *uaddr_len = sizeof(*sin);
716         return 0;
717 }
718 EXPORT_SYMBOL(inet_getname);
719
720 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
721                  size_t size)
722 {
723         struct sock *sk = sock->sk;
724
725         sock_rps_record_flow(sk);
726
727         /* We may need to bind the socket. */
728         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
729                 return -EAGAIN;
730
731         return sk->sk_prot->sendmsg(iocb, sk, msg, size);
732 }
733 EXPORT_SYMBOL(inet_sendmsg);
734
735 static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
736                              size_t size, int flags)
737 {
738         struct sock *sk = sock->sk;
739
740         sock_rps_record_flow(sk);
741
742         /* We may need to bind the socket. */
743         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
744                 return -EAGAIN;
745
746         if (sk->sk_prot->sendpage)
747                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
748         return sock_no_sendpage(sock, page, offset, size, flags);
749 }
750
751 int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
752                  size_t size, int flags)
753 {
754         struct sock *sk = sock->sk;
755         int addr_len = 0;
756         int err;
757
758         sock_rps_record_flow(sk);
759
760         err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
761                                    flags & ~MSG_DONTWAIT, &addr_len);
762         if (err >= 0)
763                 msg->msg_namelen = addr_len;
764         return err;
765 }
766 EXPORT_SYMBOL(inet_recvmsg);
767
768 int inet_shutdown(struct socket *sock, int how)
769 {
770         struct sock *sk = sock->sk;
771         int err = 0;
772
773         /* This should really check to make sure
774          * the socket is a TCP socket. (WHY AC...)
775          */
776         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
777                        1->2 bit 2 snds.
778                        2->3 */
779         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
780                 return -EINVAL;
781
782         lock_sock(sk);
783         if (sock->state == SS_CONNECTING) {
784                 if ((1 << sk->sk_state) &
785                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
786                         sock->state = SS_DISCONNECTING;
787                 else
788                         sock->state = SS_CONNECTED;
789         }
790
791         switch (sk->sk_state) {
792         case TCP_CLOSE:
793                 err = -ENOTCONN;
794                 /* Hack to wake up other listeners, who can poll for
795                    POLLHUP, even on eg. unconnected UDP sockets -- RR */
796         default:
797                 sk->sk_shutdown |= how;
798                 if (sk->sk_prot->shutdown)
799                         sk->sk_prot->shutdown(sk, how);
800                 break;
801
802         /* Remaining two branches are temporary solution for missing
803          * close() in multithreaded environment. It is _not_ a good idea,
804          * but we have no choice until close() is repaired at VFS level.
805          */
806         case TCP_LISTEN:
807                 if (!(how & RCV_SHUTDOWN))
808                         break;
809                 /* Fall through */
810         case TCP_SYN_SENT:
811                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
812                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
813                 break;
814         }
815
816         /* Wake up anyone sleeping in poll. */
817         sk->sk_state_change(sk);
818         release_sock(sk);
819         return err;
820 }
821 EXPORT_SYMBOL(inet_shutdown);
822
823 /*
824  *      ioctl() calls you can issue on an INET socket. Most of these are
825  *      device configuration and stuff and very rarely used. Some ioctls
826  *      pass on to the socket itself.
827  *
828  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
829  *      loads the devconfigure module does its configuring and unloads it.
830  *      There's a good 20K of config code hanging around the kernel.
831  */
832
833 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
834 {
835         struct sock *sk = sock->sk;
836         int err = 0;
837         struct net *net = sock_net(sk);
838
839         switch (cmd) {
840         case SIOCGSTAMP:
841                 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
842                 break;
843         case SIOCGSTAMPNS:
844                 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
845                 break;
846         case SIOCADDRT:
847         case SIOCDELRT:
848         case SIOCRTMSG:
849                 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
850                 break;
851         case SIOCDARP:
852         case SIOCGARP:
853         case SIOCSARP:
854                 err = arp_ioctl(net, cmd, (void __user *)arg);
855                 break;
856         case SIOCGIFADDR:
857         case SIOCSIFADDR:
858         case SIOCGIFBRDADDR:
859         case SIOCSIFBRDADDR:
860         case SIOCGIFNETMASK:
861         case SIOCSIFNETMASK:
862         case SIOCGIFDSTADDR:
863         case SIOCSIFDSTADDR:
864         case SIOCSIFPFLAGS:
865         case SIOCGIFPFLAGS:
866         case SIOCSIFFLAGS:
867                 err = devinet_ioctl(net, cmd, (void __user *)arg);
868                 break;
869         default:
870                 if (sk->sk_prot->ioctl)
871                         err = sk->sk_prot->ioctl(sk, cmd, arg);
872                 else
873                         err = -ENOIOCTLCMD;
874                 break;
875         }
876         return err;
877 }
878 EXPORT_SYMBOL(inet_ioctl);
879
880 const struct proto_ops inet_stream_ops = {
881         .family            = PF_INET,
882         .owner             = THIS_MODULE,
883         .release           = inet_release,
884         .bind              = inet_bind,
885         .connect           = inet_stream_connect,
886         .socketpair        = sock_no_socketpair,
887         .accept            = inet_accept,
888         .getname           = inet_getname,
889         .poll              = tcp_poll,
890         .ioctl             = inet_ioctl,
891         .listen            = inet_listen,
892         .shutdown          = inet_shutdown,
893         .setsockopt        = sock_common_setsockopt,
894         .getsockopt        = sock_common_getsockopt,
895         .sendmsg           = tcp_sendmsg,
896         .recvmsg           = inet_recvmsg,
897         .mmap              = sock_no_mmap,
898         .sendpage          = tcp_sendpage,
899         .splice_read       = tcp_splice_read,
900 #ifdef CONFIG_COMPAT
901         .compat_setsockopt = compat_sock_common_setsockopt,
902         .compat_getsockopt = compat_sock_common_getsockopt,
903 #endif
904 };
905 EXPORT_SYMBOL(inet_stream_ops);
906
907 const struct proto_ops inet_dgram_ops = {
908         .family            = PF_INET,
909         .owner             = THIS_MODULE,
910         .release           = inet_release,
911         .bind              = inet_bind,
912         .connect           = inet_dgram_connect,
913         .socketpair        = sock_no_socketpair,
914         .accept            = sock_no_accept,
915         .getname           = inet_getname,
916         .poll              = udp_poll,
917         .ioctl             = inet_ioctl,
918         .listen            = sock_no_listen,
919         .shutdown          = inet_shutdown,
920         .setsockopt        = sock_common_setsockopt,
921         .getsockopt        = sock_common_getsockopt,
922         .sendmsg           = inet_sendmsg,
923         .recvmsg           = inet_recvmsg,
924         .mmap              = sock_no_mmap,
925         .sendpage          = inet_sendpage,
926 #ifdef CONFIG_COMPAT
927         .compat_setsockopt = compat_sock_common_setsockopt,
928         .compat_getsockopt = compat_sock_common_getsockopt,
929 #endif
930 };
931 EXPORT_SYMBOL(inet_dgram_ops);
932
933 /*
934  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
935  * udp_poll
936  */
937 static const struct proto_ops inet_sockraw_ops = {
938         .family            = PF_INET,
939         .owner             = THIS_MODULE,
940         .release           = inet_release,
941         .bind              = inet_bind,
942         .connect           = inet_dgram_connect,
943         .socketpair        = sock_no_socketpair,
944         .accept            = sock_no_accept,
945         .getname           = inet_getname,
946         .poll              = datagram_poll,
947         .ioctl             = inet_ioctl,
948         .listen            = sock_no_listen,
949         .shutdown          = inet_shutdown,
950         .setsockopt        = sock_common_setsockopt,
951         .getsockopt        = sock_common_getsockopt,
952         .sendmsg           = inet_sendmsg,
953         .recvmsg           = inet_recvmsg,
954         .mmap              = sock_no_mmap,
955         .sendpage          = inet_sendpage,
956 #ifdef CONFIG_COMPAT
957         .compat_setsockopt = compat_sock_common_setsockopt,
958         .compat_getsockopt = compat_sock_common_getsockopt,
959 #endif
960 };
961
962 static const struct net_proto_family inet_family_ops = {
963         .family = PF_INET,
964         .create = inet_create,
965         .owner  = THIS_MODULE,
966 };
967
968 /* Upon startup we insert all the elements in inetsw_array[] into
969  * the linked list inetsw.
970  */
971 static struct inet_protosw inetsw_array[] =
972 {
973         {
974                 .type =       SOCK_STREAM,
975                 .protocol =   IPPROTO_TCP,
976                 .prot =       &tcp_prot,
977                 .ops =        &inet_stream_ops,
978                 .no_check =   0,
979                 .flags =      INET_PROTOSW_PERMANENT |
980                               INET_PROTOSW_ICSK,
981         },
982
983         {
984                 .type =       SOCK_DGRAM,
985                 .protocol =   IPPROTO_UDP,
986                 .prot =       &udp_prot,
987                 .ops =        &inet_dgram_ops,
988                 .no_check =   UDP_CSUM_DEFAULT,
989                 .flags =      INET_PROTOSW_PERMANENT,
990        },
991
992
993        {
994                .type =       SOCK_RAW,
995                .protocol =   IPPROTO_IP,        /* wild card */
996                .prot =       &raw_prot,
997                .ops =        &inet_sockraw_ops,
998                .no_check =   UDP_CSUM_DEFAULT,
999                .flags =      INET_PROTOSW_REUSE,
1000        }
1001 };
1002
1003 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1004
1005 void inet_register_protosw(struct inet_protosw *p)
1006 {
1007         struct list_head *lh;
1008         struct inet_protosw *answer;
1009         int protocol = p->protocol;
1010         struct list_head *last_perm;
1011
1012         spin_lock_bh(&inetsw_lock);
1013
1014         if (p->type >= SOCK_MAX)
1015                 goto out_illegal;
1016
1017         /* If we are trying to override a permanent protocol, bail. */
1018         answer = NULL;
1019         last_perm = &inetsw[p->type];
1020         list_for_each(lh, &inetsw[p->type]) {
1021                 answer = list_entry(lh, struct inet_protosw, list);
1022
1023                 /* Check only the non-wild match. */
1024                 if (INET_PROTOSW_PERMANENT & answer->flags) {
1025                         if (protocol == answer->protocol)
1026                                 break;
1027                         last_perm = lh;
1028                 }
1029
1030                 answer = NULL;
1031         }
1032         if (answer)
1033                 goto out_permanent;
1034
1035         /* Add the new entry after the last permanent entry if any, so that
1036          * the new entry does not override a permanent entry when matched with
1037          * a wild-card protocol. But it is allowed to override any existing
1038          * non-permanent entry.  This means that when we remove this entry, the
1039          * system automatically returns to the old behavior.
1040          */
1041         list_add_rcu(&p->list, last_perm);
1042 out:
1043         spin_unlock_bh(&inetsw_lock);
1044
1045         return;
1046
1047 out_permanent:
1048         printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1049                protocol);
1050         goto out;
1051
1052 out_illegal:
1053         printk(KERN_ERR
1054                "Ignoring attempt to register invalid socket type %d.\n",
1055                p->type);
1056         goto out;
1057 }
1058 EXPORT_SYMBOL(inet_register_protosw);
1059
1060 void inet_unregister_protosw(struct inet_protosw *p)
1061 {
1062         if (INET_PROTOSW_PERMANENT & p->flags) {
1063                 printk(KERN_ERR
1064                        "Attempt to unregister permanent protocol %d.\n",
1065                        p->protocol);
1066         } else {
1067                 spin_lock_bh(&inetsw_lock);
1068                 list_del_rcu(&p->list);
1069                 spin_unlock_bh(&inetsw_lock);
1070
1071                 synchronize_net();
1072         }
1073 }
1074 EXPORT_SYMBOL(inet_unregister_protosw);
1075
1076 /*
1077  *      Shall we try to damage output packets if routing dev changes?
1078  */
1079
1080 int sysctl_ip_dynaddr __read_mostly;
1081
1082 static int inet_sk_reselect_saddr(struct sock *sk)
1083 {
1084         struct inet_sock *inet = inet_sk(sk);
1085         int err;
1086         struct rtable *rt;
1087         __be32 old_saddr = inet->inet_saddr;
1088         __be32 new_saddr;
1089         __be32 daddr = inet->inet_daddr;
1090
1091         if (inet->opt && inet->opt->srr)
1092                 daddr = inet->opt->faddr;
1093
1094         /* Query new route. */
1095         err = ip_route_connect(&rt, daddr, 0,
1096                                RT_CONN_FLAGS(sk),
1097                                sk->sk_bound_dev_if,
1098                                sk->sk_protocol,
1099                                inet->inet_sport, inet->inet_dport, sk, 0);
1100         if (err)
1101                 return err;
1102
1103         sk_setup_caps(sk, &rt->u.dst);
1104
1105         new_saddr = rt->rt_src;
1106
1107         if (new_saddr == old_saddr)
1108                 return 0;
1109
1110         if (sysctl_ip_dynaddr > 1) {
1111                 printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1112                        __func__, &old_saddr, &new_saddr);
1113         }
1114
1115         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1116
1117         /*
1118          * XXX The only one ugly spot where we need to
1119          * XXX really change the sockets identity after
1120          * XXX it has entered the hashes. -DaveM
1121          *
1122          * Besides that, it does not check for connection
1123          * uniqueness. Wait for troubles.
1124          */
1125         __sk_prot_rehash(sk);
1126         return 0;
1127 }
1128
1129 int inet_sk_rebuild_header(struct sock *sk)
1130 {
1131         struct inet_sock *inet = inet_sk(sk);
1132         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1133         __be32 daddr;
1134         int err;
1135
1136         /* Route is OK, nothing to do. */
1137         if (rt)
1138                 return 0;
1139
1140         /* Reroute. */
1141         daddr = inet->inet_daddr;
1142         if (inet->opt && inet->opt->srr)
1143                 daddr = inet->opt->faddr;
1144 {
1145         struct flowi fl = {
1146                 .oif = sk->sk_bound_dev_if,
1147                 .mark = sk->sk_mark,
1148                 .nl_u = {
1149                         .ip4_u = {
1150                                 .daddr  = daddr,
1151                                 .saddr  = inet->inet_saddr,
1152                                 .tos    = RT_CONN_FLAGS(sk),
1153                         },
1154                 },
1155                 .proto = sk->sk_protocol,
1156                 .flags = inet_sk_flowi_flags(sk),
1157                 .uli_u = {
1158                         .ports = {
1159                                 .sport = inet->inet_sport,
1160                                 .dport = inet->inet_dport,
1161                         },
1162                 },
1163         };
1164
1165         security_sk_classify_flow(sk, &fl);
1166         err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1167 }
1168         if (!err)
1169                 sk_setup_caps(sk, &rt->u.dst);
1170         else {
1171                 /* Routing failed... */
1172                 sk->sk_route_caps = 0;
1173                 /*
1174                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1175                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1176                  */
1177                 if (!sysctl_ip_dynaddr ||
1178                     sk->sk_state != TCP_SYN_SENT ||
1179                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1180                     (err = inet_sk_reselect_saddr(sk)) != 0)
1181                         sk->sk_err_soft = -err;
1182         }
1183
1184         return err;
1185 }
1186 EXPORT_SYMBOL(inet_sk_rebuild_header);
1187
1188 static int inet_gso_send_check(struct sk_buff *skb)
1189 {
1190         struct iphdr *iph;
1191         const struct net_protocol *ops;
1192         int proto;
1193         int ihl;
1194         int err = -EINVAL;
1195
1196         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1197                 goto out;
1198
1199         iph = ip_hdr(skb);
1200         ihl = iph->ihl * 4;
1201         if (ihl < sizeof(*iph))
1202                 goto out;
1203
1204         if (unlikely(!pskb_may_pull(skb, ihl)))
1205                 goto out;
1206
1207         __skb_pull(skb, ihl);
1208         skb_reset_transport_header(skb);
1209         iph = ip_hdr(skb);
1210         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1211         err = -EPROTONOSUPPORT;
1212
1213         rcu_read_lock();
1214         ops = rcu_dereference(inet_protos[proto]);
1215         if (likely(ops && ops->gso_send_check))
1216                 err = ops->gso_send_check(skb);
1217         rcu_read_unlock();
1218
1219 out:
1220         return err;
1221 }
1222
1223 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1224 {
1225         struct sk_buff *segs = ERR_PTR(-EINVAL);
1226         struct iphdr *iph;
1227         const struct net_protocol *ops;
1228         int proto;
1229         int ihl;
1230         int id;
1231         unsigned int offset = 0;
1232
1233         if (!(features & NETIF_F_V4_CSUM))
1234                 features &= ~NETIF_F_SG;
1235
1236         if (unlikely(skb_shinfo(skb)->gso_type &
1237                      ~(SKB_GSO_TCPV4 |
1238                        SKB_GSO_UDP |
1239                        SKB_GSO_DODGY |
1240                        SKB_GSO_TCP_ECN |
1241                        0)))
1242                 goto out;
1243
1244         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1245                 goto out;
1246
1247         iph = ip_hdr(skb);
1248         ihl = iph->ihl * 4;
1249         if (ihl < sizeof(*iph))
1250                 goto out;
1251
1252         if (unlikely(!pskb_may_pull(skb, ihl)))
1253                 goto out;
1254
1255         __skb_pull(skb, ihl);
1256         skb_reset_transport_header(skb);
1257         iph = ip_hdr(skb);
1258         id = ntohs(iph->id);
1259         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1260         segs = ERR_PTR(-EPROTONOSUPPORT);
1261
1262         rcu_read_lock();
1263         ops = rcu_dereference(inet_protos[proto]);
1264         if (likely(ops && ops->gso_segment))
1265                 segs = ops->gso_segment(skb, features);
1266         rcu_read_unlock();
1267
1268         if (!segs || IS_ERR(segs))
1269                 goto out;
1270
1271         skb = segs;
1272         do {
1273                 iph = ip_hdr(skb);
1274                 if (proto == IPPROTO_UDP) {
1275                         iph->id = htons(id);
1276                         iph->frag_off = htons(offset >> 3);
1277                         if (skb->next != NULL)
1278                                 iph->frag_off |= htons(IP_MF);
1279                         offset += (skb->len - skb->mac_len - iph->ihl * 4);
1280                 } else
1281                         iph->id = htons(id++);
1282                 iph->tot_len = htons(skb->len - skb->mac_len);
1283                 iph->check = 0;
1284                 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1285         } while ((skb = skb->next));
1286
1287 out:
1288         return segs;
1289 }
1290
1291 static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1292                                          struct sk_buff *skb)
1293 {
1294         const struct net_protocol *ops;
1295         struct sk_buff **pp = NULL;
1296         struct sk_buff *p;
1297         struct iphdr *iph;
1298         unsigned int hlen;
1299         unsigned int off;
1300         unsigned int id;
1301         int flush = 1;
1302         int proto;
1303
1304         off = skb_gro_offset(skb);
1305         hlen = off + sizeof(*iph);
1306         iph = skb_gro_header_fast(skb, off);
1307         if (skb_gro_header_hard(skb, hlen)) {
1308                 iph = skb_gro_header_slow(skb, hlen, off);
1309                 if (unlikely(!iph))
1310                         goto out;
1311         }
1312
1313         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1314
1315         rcu_read_lock();
1316         ops = rcu_dereference(inet_protos[proto]);
1317         if (!ops || !ops->gro_receive)
1318                 goto out_unlock;
1319
1320         if (*(u8 *)iph != 0x45)
1321                 goto out_unlock;
1322
1323         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1324                 goto out_unlock;
1325
1326         id = ntohl(*(__be32 *)&iph->id);
1327         flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1328         id >>= 16;
1329
1330         for (p = *head; p; p = p->next) {
1331                 struct iphdr *iph2;
1332
1333                 if (!NAPI_GRO_CB(p)->same_flow)
1334                         continue;
1335
1336                 iph2 = ip_hdr(p);
1337
1338                 if ((iph->protocol ^ iph2->protocol) |
1339                     (iph->tos ^ iph2->tos) |
1340                     ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1341                     ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1342                         NAPI_GRO_CB(p)->same_flow = 0;
1343                         continue;
1344                 }
1345
1346                 /* All fields must match except length and checksum. */
1347                 NAPI_GRO_CB(p)->flush |=
1348                         (iph->ttl ^ iph2->ttl) |
1349                         ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1350
1351                 NAPI_GRO_CB(p)->flush |= flush;
1352         }
1353
1354         NAPI_GRO_CB(skb)->flush |= flush;
1355         skb_gro_pull(skb, sizeof(*iph));
1356         skb_set_transport_header(skb, skb_gro_offset(skb));
1357
1358         pp = ops->gro_receive(head, skb);
1359
1360 out_unlock:
1361         rcu_read_unlock();
1362
1363 out:
1364         NAPI_GRO_CB(skb)->flush |= flush;
1365
1366         return pp;
1367 }
1368
1369 static int inet_gro_complete(struct sk_buff *skb)
1370 {
1371         const struct net_protocol *ops;
1372         struct iphdr *iph = ip_hdr(skb);
1373         int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1374         int err = -ENOSYS;
1375         __be16 newlen = htons(skb->len - skb_network_offset(skb));
1376
1377         csum_replace2(&iph->check, iph->tot_len, newlen);
1378         iph->tot_len = newlen;
1379
1380         rcu_read_lock();
1381         ops = rcu_dereference(inet_protos[proto]);
1382         if (WARN_ON(!ops || !ops->gro_complete))
1383                 goto out_unlock;
1384
1385         err = ops->gro_complete(skb);
1386
1387 out_unlock:
1388         rcu_read_unlock();
1389
1390         return err;
1391 }
1392
1393 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1394                          unsigned short type, unsigned char protocol,
1395                          struct net *net)
1396 {
1397         struct socket *sock;
1398         int rc = sock_create_kern(family, type, protocol, &sock);
1399
1400         if (rc == 0) {
1401                 *sk = sock->sk;
1402                 (*sk)->sk_allocation = GFP_ATOMIC;
1403                 /*
1404                  * Unhash it so that IP input processing does not even see it,
1405                  * we do not wish this socket to see incoming packets.
1406                  */
1407                 (*sk)->sk_prot->unhash(*sk);
1408
1409                 sk_change_net(*sk, net);
1410         }
1411         return rc;
1412 }
1413 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1414
1415 unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1416 {
1417         unsigned long res = 0;
1418         int i;
1419
1420         for_each_possible_cpu(i) {
1421                 res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1422                 res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1423         }
1424         return res;
1425 }
1426 EXPORT_SYMBOL_GPL(snmp_fold_field);
1427
1428 int snmp_mib_init(void __percpu *ptr[2], size_t mibsize)
1429 {
1430         BUG_ON(ptr == NULL);
1431         ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long));
1432         if (!ptr[0])
1433                 goto err0;
1434         ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long));
1435         if (!ptr[1])
1436                 goto err1;
1437         return 0;
1438 err1:
1439         free_percpu(ptr[0]);
1440         ptr[0] = NULL;
1441 err0:
1442         return -ENOMEM;
1443 }
1444 EXPORT_SYMBOL_GPL(snmp_mib_init);
1445
1446 void snmp_mib_free(void __percpu *ptr[2])
1447 {
1448         BUG_ON(ptr == NULL);
1449         free_percpu(ptr[0]);
1450         free_percpu(ptr[1]);
1451         ptr[0] = ptr[1] = NULL;
1452 }
1453 EXPORT_SYMBOL_GPL(snmp_mib_free);
1454
1455 #ifdef CONFIG_IP_MULTICAST
1456 static const struct net_protocol igmp_protocol = {
1457         .handler =      igmp_rcv,
1458         .netns_ok =     1,
1459 };
1460 #endif
1461
1462 static const struct net_protocol tcp_protocol = {
1463         .handler =      tcp_v4_rcv,
1464         .err_handler =  tcp_v4_err,
1465         .gso_send_check = tcp_v4_gso_send_check,
1466         .gso_segment =  tcp_tso_segment,
1467         .gro_receive =  tcp4_gro_receive,
1468         .gro_complete = tcp4_gro_complete,
1469         .no_policy =    1,
1470         .netns_ok =     1,
1471 };
1472
1473 static const struct net_protocol udp_protocol = {
1474         .handler =      udp_rcv,
1475         .err_handler =  udp_err,
1476         .gso_send_check = udp4_ufo_send_check,
1477         .gso_segment = udp4_ufo_fragment,
1478         .no_policy =    1,
1479         .netns_ok =     1,
1480 };
1481
1482 static const struct net_protocol icmp_protocol = {
1483         .handler =      icmp_rcv,
1484         .no_policy =    1,
1485         .netns_ok =     1,
1486 };
1487
1488 static __net_init int ipv4_mib_init_net(struct net *net)
1489 {
1490         if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1491                           sizeof(struct tcp_mib)) < 0)
1492                 goto err_tcp_mib;
1493         if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1494                           sizeof(struct ipstats_mib)) < 0)
1495                 goto err_ip_mib;
1496         if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1497                           sizeof(struct linux_mib)) < 0)
1498                 goto err_net_mib;
1499         if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1500                           sizeof(struct udp_mib)) < 0)
1501                 goto err_udp_mib;
1502         if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1503                           sizeof(struct udp_mib)) < 0)
1504                 goto err_udplite_mib;
1505         if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1506                           sizeof(struct icmp_mib)) < 0)
1507                 goto err_icmp_mib;
1508         if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1509                           sizeof(struct icmpmsg_mib)) < 0)
1510                 goto err_icmpmsg_mib;
1511
1512         tcp_mib_init(net);
1513         return 0;
1514
1515 err_icmpmsg_mib:
1516         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1517 err_icmp_mib:
1518         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1519 err_udplite_mib:
1520         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1521 err_udp_mib:
1522         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1523 err_net_mib:
1524         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1525 err_ip_mib:
1526         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1527 err_tcp_mib:
1528         return -ENOMEM;
1529 }
1530
1531 static __net_exit void ipv4_mib_exit_net(struct net *net)
1532 {
1533         snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
1534         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1535         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1536         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1537         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1538         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1539         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1540 }
1541
1542 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1543         .init = ipv4_mib_init_net,
1544         .exit = ipv4_mib_exit_net,
1545 };
1546
1547 static int __init init_ipv4_mibs(void)
1548 {
1549         return register_pernet_subsys(&ipv4_mib_ops);
1550 }
1551
1552 static int ipv4_proc_init(void);
1553
1554 /*
1555  *      IP protocol layer initialiser
1556  */
1557
1558 static struct packet_type ip_packet_type __read_mostly = {
1559         .type = cpu_to_be16(ETH_P_IP),
1560         .func = ip_rcv,
1561         .gso_send_check = inet_gso_send_check,
1562         .gso_segment = inet_gso_segment,
1563         .gro_receive = inet_gro_receive,
1564         .gro_complete = inet_gro_complete,
1565 };
1566
1567 static int __init inet_init(void)
1568 {
1569         struct sk_buff *dummy_skb;
1570         struct inet_protosw *q;
1571         struct list_head *r;
1572         int rc = -EINVAL;
1573
1574         BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1575
1576         sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1577         if (!sysctl_local_reserved_ports)
1578                 goto out;
1579
1580         rc = proto_register(&tcp_prot, 1);
1581         if (rc)
1582                 goto out_free_reserved_ports;
1583
1584         rc = proto_register(&udp_prot, 1);
1585         if (rc)
1586                 goto out_unregister_tcp_proto;
1587
1588         rc = proto_register(&raw_prot, 1);
1589         if (rc)
1590                 goto out_unregister_udp_proto;
1591
1592         /*
1593          *      Tell SOCKET that we are alive...
1594          */
1595
1596         (void)sock_register(&inet_family_ops);
1597
1598 #ifdef CONFIG_SYSCTL
1599         ip_static_sysctl_init();
1600 #endif
1601
1602         /*
1603          *      Add all the base protocols.
1604          */
1605
1606         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1607                 printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1608         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1609                 printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1610         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1611                 printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1612 #ifdef CONFIG_IP_MULTICAST
1613         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1614                 printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1615 #endif
1616
1617         /* Register the socket-side information for inet_create. */
1618         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1619                 INIT_LIST_HEAD(r);
1620
1621         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1622                 inet_register_protosw(q);
1623
1624         /*
1625          *      Set the ARP module up
1626          */
1627
1628         arp_init();
1629
1630         /*
1631          *      Set the IP module up
1632          */
1633
1634         ip_init();
1635
1636         tcp_v4_init();
1637
1638         /* Setup TCP slab cache for open requests. */
1639         tcp_init();
1640
1641         /* Setup UDP memory threshold */
1642         udp_init();
1643
1644         /* Add UDP-Lite (RFC 3828) */
1645         udplite4_register();
1646
1647         /*
1648          *      Set the ICMP layer up
1649          */
1650
1651         if (icmp_init() < 0)
1652                 panic("Failed to create the ICMP control socket.\n");
1653
1654         /*
1655          *      Initialise the multicast router
1656          */
1657 #if defined(CONFIG_IP_MROUTE)
1658         if (ip_mr_init())
1659                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1660 #endif
1661         /*
1662          *      Initialise per-cpu ipv4 mibs
1663          */
1664
1665         if (init_ipv4_mibs())
1666                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1667
1668         ipv4_proc_init();
1669
1670         ipfrag_init();
1671
1672         dev_add_pack(&ip_packet_type);
1673
1674         rc = 0;
1675 out:
1676         return rc;
1677 out_unregister_udp_proto:
1678         proto_unregister(&udp_prot);
1679 out_unregister_tcp_proto:
1680         proto_unregister(&tcp_prot);
1681 out_free_reserved_ports:
1682         kfree(sysctl_local_reserved_ports);
1683         goto out;
1684 }
1685
1686 fs_initcall(inet_init);
1687
1688 /* ------------------------------------------------------------------------ */
1689
1690 #ifdef CONFIG_PROC_FS
1691 static int __init ipv4_proc_init(void)
1692 {
1693         int rc = 0;
1694
1695         if (raw_proc_init())
1696                 goto out_raw;
1697         if (tcp4_proc_init())
1698                 goto out_tcp;
1699         if (udp4_proc_init())
1700                 goto out_udp;
1701         if (ip_misc_proc_init())
1702                 goto out_misc;
1703 out:
1704         return rc;
1705 out_misc:
1706         udp4_proc_exit();
1707 out_udp:
1708         tcp4_proc_exit();
1709 out_tcp:
1710         raw_proc_exit();
1711 out_raw:
1712         rc = -ENOMEM;
1713         goto out;
1714 }
1715
1716 #else /* CONFIG_PROC_FS */
1717 static int __init ipv4_proc_init(void)
1718 {
1719         return 0;
1720 }
1721 #endif /* CONFIG_PROC_FS */
1722
1723 MODULE_ALIAS_NETPROTO(PF_INET);
1724