e2ab9681f53a010200a4386105ff28c9011058b7
[pandora-kernel.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 <net/ping.h>
109 #include <linux/skbuff.h>
110 #include <net/sock.h>
111 #include <net/raw.h>
112 #include <net/icmp.h>
113 #include <net/ipip.h>
114 #include <net/inet_common.h>
115 #include <net/xfrm.h>
116 #include <net/net_namespace.h>
117 #ifdef CONFIG_IP_MROUTE
118 #include <linux/mroute.h>
119 #endif
120
121
122 /* The inetsw table contains everything that inet_create needs to
123  * build a new socket.
124  */
125 static struct list_head inetsw[SOCK_MAX];
126 static DEFINE_SPINLOCK(inetsw_lock);
127
128 struct ipv4_config ipv4_config;
129 EXPORT_SYMBOL(ipv4_config);
130
131 /* New destruction routine */
132
133 void inet_sock_destruct(struct sock *sk)
134 {
135         struct inet_sock *inet = inet_sk(sk);
136
137         __skb_queue_purge(&sk->sk_receive_queue);
138         __skb_queue_purge(&sk->sk_error_queue);
139
140         sk_mem_reclaim(sk);
141
142         if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
143                 pr_err("Attempt to release TCP socket in state %d %p\n",
144                        sk->sk_state, sk);
145                 return;
146         }
147         if (!sock_flag(sk, SOCK_DEAD)) {
148                 pr_err("Attempt to release alive inet socket %p\n", sk);
149                 return;
150         }
151
152         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
153         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
154         WARN_ON(sk->sk_wmem_queued);
155         WARN_ON(sk->sk_forward_alloc);
156
157         kfree(rcu_dereference_protected(inet->inet_opt, 1));
158         dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
159         sk_refcnt_debug_dec(sk);
160 }
161 EXPORT_SYMBOL(inet_sock_destruct);
162
163 /*
164  *      The routines beyond this point handle the behaviour of an AF_INET
165  *      socket object. Mostly it punts to the subprotocols of IP to do
166  *      the work.
167  */
168
169 /*
170  *      Automatically bind an unbound socket.
171  */
172
173 static int inet_autobind(struct sock *sk)
174 {
175         struct inet_sock *inet;
176         /* We may need to bind the socket. */
177         lock_sock(sk);
178         inet = inet_sk(sk);
179         if (!inet->inet_num) {
180                 if (sk->sk_prot->get_port(sk, 0)) {
181                         release_sock(sk);
182                         return -EAGAIN;
183                 }
184                 inet->inet_sport = htons(inet->inet_num);
185         }
186         release_sock(sk);
187         return 0;
188 }
189
190 /*
191  *      Move a socket into listening state.
192  */
193 int inet_listen(struct socket *sock, int backlog)
194 {
195         struct sock *sk = sock->sk;
196         unsigned char old_state;
197         int err;
198
199         lock_sock(sk);
200
201         err = -EINVAL;
202         if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
203                 goto out;
204
205         old_state = sk->sk_state;
206         if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
207                 goto out;
208
209         /* Really, if the socket is already in listen state
210          * we can only allow the backlog to be adjusted.
211          */
212         if (old_state != TCP_LISTEN) {
213                 err = inet_csk_listen_start(sk, backlog);
214                 if (err)
215                         goto out;
216         }
217         sk->sk_max_ack_backlog = backlog;
218         err = 0;
219
220 out:
221         release_sock(sk);
222         return err;
223 }
224 EXPORT_SYMBOL(inet_listen);
225
226 u32 inet_ehash_secret __read_mostly;
227 EXPORT_SYMBOL(inet_ehash_secret);
228
229 u32 ipv6_hash_secret __read_mostly;
230 EXPORT_SYMBOL(ipv6_hash_secret);
231
232 /*
233  * inet_ehash_secret must be set exactly once, and to a non nul value
234  * ipv6_hash_secret must be set exactly once.
235  */
236 void build_ehash_secret(void)
237 {
238         u32 rnd;
239
240         do {
241                 get_random_bytes(&rnd, sizeof(rnd));
242         } while (rnd == 0);
243
244         if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0)
245                 get_random_bytes(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
246 }
247 EXPORT_SYMBOL(build_ehash_secret);
248
249 static inline int inet_netns_ok(struct net *net, int protocol)
250 {
251         int hash;
252         const struct net_protocol *ipprot;
253
254         if (net_eq(net, &init_net))
255                 return 1;
256
257         hash = protocol & (MAX_INET_PROTOS - 1);
258         ipprot = rcu_dereference(inet_protos[hash]);
259
260         if (ipprot == NULL)
261                 /* raw IP is OK */
262                 return 1;
263         return ipprot->netns_ok;
264 }
265
266 /*
267  *      Create an inet socket.
268  */
269
270 static int inet_create(struct net *net, struct socket *sock, int protocol,
271                        int kern)
272 {
273         struct sock *sk;
274         struct inet_protosw *answer;
275         struct inet_sock *inet;
276         struct proto *answer_prot;
277         unsigned char answer_flags;
278         char answer_no_check;
279         int try_loading_module = 0;
280         int err;
281
282         if (protocol < 0 || protocol >= IPPROTO_MAX)
283                 return -EINVAL;
284
285         if (unlikely(!inet_ehash_secret))
286                 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
287                         build_ehash_secret();
288
289         sock->state = SS_UNCONNECTED;
290
291         /* Look for the requested type/protocol pair. */
292 lookup_protocol:
293         err = -ESOCKTNOSUPPORT;
294         rcu_read_lock();
295         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
296
297                 err = 0;
298                 /* Check the non-wild match. */
299                 if (protocol == answer->protocol) {
300                         if (protocol != IPPROTO_IP)
301                                 break;
302                 } else {
303                         /* Check for the two wild cases. */
304                         if (IPPROTO_IP == protocol) {
305                                 protocol = answer->protocol;
306                                 break;
307                         }
308                         if (IPPROTO_IP == answer->protocol)
309                                 break;
310                 }
311                 err = -EPROTONOSUPPORT;
312         }
313
314         if (unlikely(err)) {
315                 if (try_loading_module < 2) {
316                         rcu_read_unlock();
317                         /*
318                          * Be more specific, e.g. net-pf-2-proto-132-type-1
319                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
320                          */
321                         if (++try_loading_module == 1)
322                                 request_module("net-pf-%d-proto-%d-type-%d",
323                                                PF_INET, protocol, sock->type);
324                         /*
325                          * Fall back to generic, e.g. net-pf-2-proto-132
326                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
327                          */
328                         else
329                                 request_module("net-pf-%d-proto-%d",
330                                                PF_INET, protocol);
331                         goto lookup_protocol;
332                 } else
333                         goto out_rcu_unlock;
334         }
335
336         err = -EPERM;
337         if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
338                 goto out_rcu_unlock;
339
340         err = -EAFNOSUPPORT;
341         if (!inet_netns_ok(net, protocol))
342                 goto out_rcu_unlock;
343
344         sock->ops = answer->ops;
345         answer_prot = answer->prot;
346         answer_no_check = answer->no_check;
347         answer_flags = answer->flags;
348         rcu_read_unlock();
349
350         WARN_ON(answer_prot->slab == NULL);
351
352         err = -ENOBUFS;
353         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
354         if (sk == NULL)
355                 goto out;
356
357         err = 0;
358         sk->sk_no_check = answer_no_check;
359         if (INET_PROTOSW_REUSE & answer_flags)
360                 sk->sk_reuse = 1;
361
362         inet = inet_sk(sk);
363         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
364
365         inet->nodefrag = 0;
366
367         if (SOCK_RAW == sock->type) {
368                 inet->inet_num = protocol;
369                 if (IPPROTO_RAW == protocol)
370                         inet->hdrincl = 1;
371         }
372
373         if (ipv4_config.no_pmtu_disc)
374                 inet->pmtudisc = IP_PMTUDISC_DONT;
375         else
376                 inet->pmtudisc = IP_PMTUDISC_WANT;
377
378         inet->inet_id = 0;
379
380         sock_init_data(sock, sk);
381
382         sk->sk_destruct    = inet_sock_destruct;
383         sk->sk_protocol    = protocol;
384         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
385
386         inet->uc_ttl    = -1;
387         inet->mc_loop   = 1;
388         inet->mc_ttl    = 1;
389         inet->mc_all    = 1;
390         inet->mc_index  = 0;
391         inet->mc_list   = NULL;
392
393         sk_refcnt_debug_inc(sk);
394
395         if (inet->inet_num) {
396                 /* It assumes that any protocol which allows
397                  * the user to assign a number at socket
398                  * creation time automatically
399                  * shares.
400                  */
401                 inet->inet_sport = htons(inet->inet_num);
402                 /* Add to protocol hash chains. */
403                 sk->sk_prot->hash(sk);
404         }
405
406         if (sk->sk_prot->init) {
407                 err = sk->sk_prot->init(sk);
408                 if (err)
409                         sk_common_release(sk);
410         }
411 out:
412         return err;
413 out_rcu_unlock:
414         rcu_read_unlock();
415         goto out;
416 }
417
418
419 /*
420  *      The peer socket should always be NULL (or else). When we call this
421  *      function we are destroying the object and from then on nobody
422  *      should refer to it.
423  */
424 int inet_release(struct socket *sock)
425 {
426         struct sock *sk = sock->sk;
427
428         if (sk) {
429                 long timeout;
430
431                 sock_rps_reset_flow(sk);
432
433                 /* Applications forget to leave groups before exiting */
434                 ip_mc_drop_socket(sk);
435
436                 /* If linger is set, we don't return until the close
437                  * is complete.  Otherwise we return immediately. The
438                  * actually closing is done the same either way.
439                  *
440                  * If the close is due to the process exiting, we never
441                  * linger..
442                  */
443                 timeout = 0;
444                 if (sock_flag(sk, SOCK_LINGER) &&
445                     !(current->flags & PF_EXITING))
446                         timeout = sk->sk_lingertime;
447                 sock->sk = NULL;
448                 sk->sk_prot->close(sk, timeout);
449         }
450         return 0;
451 }
452 EXPORT_SYMBOL(inet_release);
453
454 /* It is off by default, see below. */
455 int sysctl_ip_nonlocal_bind __read_mostly;
456 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
457
458 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
459 {
460         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
461         struct sock *sk = sock->sk;
462         struct inet_sock *inet = inet_sk(sk);
463         unsigned short snum;
464         int chk_addr_ret;
465         int err;
466
467         /* If the socket has its own bind function then use it. (RAW) */
468         if (sk->sk_prot->bind) {
469                 err = sk->sk_prot->bind(sk, uaddr, addr_len);
470                 goto out;
471         }
472         err = -EINVAL;
473         if (addr_len < sizeof(struct sockaddr_in))
474                 goto out;
475
476         if (addr->sin_family != AF_INET) {
477                 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
478                  * only if s_addr is INADDR_ANY.
479                  */
480                 err = -EAFNOSUPPORT;
481                 if (addr->sin_family != AF_UNSPEC ||
482                     addr->sin_addr.s_addr != htonl(INADDR_ANY))
483                         goto out;
484         }
485
486         chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
487
488         /* Not specified by any standard per-se, however it breaks too
489          * many applications when removed.  It is unfortunate since
490          * allowing applications to make a non-local bind solves
491          * several problems with systems using dynamic addressing.
492          * (ie. your servers still start up even if your ISDN link
493          *  is temporarily down)
494          */
495         err = -EADDRNOTAVAIL;
496         if (!sysctl_ip_nonlocal_bind &&
497             !(inet->freebind || inet->transparent) &&
498             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
499             chk_addr_ret != RTN_LOCAL &&
500             chk_addr_ret != RTN_MULTICAST &&
501             chk_addr_ret != RTN_BROADCAST)
502                 goto out;
503
504         snum = ntohs(addr->sin_port);
505         err = -EACCES;
506         if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
507                 goto out;
508
509         /*      We keep a pair of addresses. rcv_saddr is the one
510          *      used by hash lookups, and saddr is used for transmit.
511          *
512          *      In the BSD API these are the same except where it
513          *      would be illegal to use them (multicast/broadcast) in
514          *      which case the sending device address is used.
515          */
516         lock_sock(sk);
517
518         /* Check these errors (active socket, double bind). */
519         err = -EINVAL;
520         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
521                 goto out_release_sock;
522
523         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
524         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
525                 inet->inet_saddr = 0;  /* Use device */
526
527         /* Make sure we are allowed to bind here. */
528         if (sk->sk_prot->get_port(sk, snum)) {
529                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
530                 err = -EADDRINUSE;
531                 goto out_release_sock;
532         }
533
534         if (inet->inet_rcv_saddr)
535                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
536         if (snum)
537                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
538         inet->inet_sport = htons(inet->inet_num);
539         inet->inet_daddr = 0;
540         inet->inet_dport = 0;
541         sk_dst_reset(sk);
542         err = 0;
543 out_release_sock:
544         release_sock(sk);
545 out:
546         return err;
547 }
548 EXPORT_SYMBOL(inet_bind);
549
550 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
551                        int addr_len, int flags)
552 {
553         struct sock *sk = sock->sk;
554
555         if (addr_len < sizeof(uaddr->sa_family))
556                 return -EINVAL;
557         if (uaddr->sa_family == AF_UNSPEC)
558                 return sk->sk_prot->disconnect(sk, flags);
559
560         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
561                 return -EAGAIN;
562         return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
563 }
564 EXPORT_SYMBOL(inet_dgram_connect);
565
566 static long inet_wait_for_connect(struct sock *sk, long timeo)
567 {
568         DEFINE_WAIT(wait);
569
570         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
571
572         /* Basic assumption: if someone sets sk->sk_err, he _must_
573          * change state of the socket from TCP_SYN_*.
574          * Connect() does not allow to get error notifications
575          * without closing the socket.
576          */
577         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
578                 release_sock(sk);
579                 timeo = schedule_timeout(timeo);
580                 lock_sock(sk);
581                 if (signal_pending(current) || !timeo)
582                         break;
583                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
584         }
585         finish_wait(sk_sleep(sk), &wait);
586         return timeo;
587 }
588
589 /*
590  *      Connect to a remote host. There is regrettably still a little
591  *      TCP 'magic' in here.
592  */
593 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
594                         int addr_len, int flags)
595 {
596         struct sock *sk = sock->sk;
597         int err;
598         long timeo;
599
600         if (addr_len < sizeof(uaddr->sa_family))
601                 return -EINVAL;
602
603         lock_sock(sk);
604
605         if (uaddr->sa_family == AF_UNSPEC) {
606                 err = sk->sk_prot->disconnect(sk, flags);
607                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
608                 goto out;
609         }
610
611         switch (sock->state) {
612         default:
613                 err = -EINVAL;
614                 goto out;
615         case SS_CONNECTED:
616                 err = -EISCONN;
617                 goto out;
618         case SS_CONNECTING:
619                 err = -EALREADY;
620                 /* Fall out of switch with err, set for this state */
621                 break;
622         case SS_UNCONNECTED:
623                 err = -EISCONN;
624                 if (sk->sk_state != TCP_CLOSE)
625                         goto out;
626
627                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
628                 if (err < 0)
629                         goto out;
630
631                 sock->state = SS_CONNECTING;
632
633                 /* Just entered SS_CONNECTING state; the only
634                  * difference is that return value in non-blocking
635                  * case is EINPROGRESS, rather than EALREADY.
636                  */
637                 err = -EINPROGRESS;
638                 break;
639         }
640
641         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
642
643         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
644                 /* Error code is set above */
645                 if (!timeo || !inet_wait_for_connect(sk, timeo))
646                         goto out;
647
648                 err = sock_intr_errno(timeo);
649                 if (signal_pending(current))
650                         goto out;
651         }
652
653         /* Connection was closed by RST, timeout, ICMP error
654          * or another process disconnected us.
655          */
656         if (sk->sk_state == TCP_CLOSE)
657                 goto sock_error;
658
659         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
660          * and error was received after socket entered established state.
661          * Hence, it is handled normally after connect() return successfully.
662          */
663
664         sock->state = SS_CONNECTED;
665         err = 0;
666 out:
667         release_sock(sk);
668         return err;
669
670 sock_error:
671         err = sock_error(sk) ? : -ECONNABORTED;
672         sock->state = SS_UNCONNECTED;
673         if (sk->sk_prot->disconnect(sk, flags))
674                 sock->state = SS_DISCONNECTING;
675         goto out;
676 }
677 EXPORT_SYMBOL(inet_stream_connect);
678
679 /*
680  *      Accept a pending connection. The TCP layer now gives BSD semantics.
681  */
682
683 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
684 {
685         struct sock *sk1 = sock->sk;
686         int err = -EINVAL;
687         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
688
689         if (!sk2)
690                 goto do_err;
691
692         lock_sock(sk2);
693
694         sock_rps_record_flow(sk2);
695         WARN_ON(!((1 << sk2->sk_state) &
696                   (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
697
698         sock_graft(sk2, newsock);
699
700         newsock->state = SS_CONNECTED;
701         err = 0;
702         release_sock(sk2);
703 do_err:
704         return err;
705 }
706 EXPORT_SYMBOL(inet_accept);
707
708
709 /*
710  *      This does both peername and sockname.
711  */
712 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
713                         int *uaddr_len, int peer)
714 {
715         struct sock *sk         = sock->sk;
716         struct inet_sock *inet  = inet_sk(sk);
717         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
718
719         sin->sin_family = AF_INET;
720         if (peer) {
721                 if (!inet->inet_dport ||
722                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
723                      peer == 1))
724                         return -ENOTCONN;
725                 sin->sin_port = inet->inet_dport;
726                 sin->sin_addr.s_addr = inet->inet_daddr;
727         } else {
728                 __be32 addr = inet->inet_rcv_saddr;
729                 if (!addr)
730                         addr = inet->inet_saddr;
731                 sin->sin_port = inet->inet_sport;
732                 sin->sin_addr.s_addr = addr;
733         }
734         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
735         *uaddr_len = sizeof(*sin);
736         return 0;
737 }
738 EXPORT_SYMBOL(inet_getname);
739
740 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
741                  size_t size)
742 {
743         struct sock *sk = sock->sk;
744
745         sock_rps_record_flow(sk);
746
747         /* We may need to bind the socket. */
748         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
749             inet_autobind(sk))
750                 return -EAGAIN;
751
752         return sk->sk_prot->sendmsg(iocb, sk, msg, size);
753 }
754 EXPORT_SYMBOL(inet_sendmsg);
755
756 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
757                       size_t size, int flags)
758 {
759         struct sock *sk = sock->sk;
760
761         sock_rps_record_flow(sk);
762
763         /* We may need to bind the socket. */
764         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
765             inet_autobind(sk))
766                 return -EAGAIN;
767
768         if (sk->sk_prot->sendpage)
769                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
770         return sock_no_sendpage(sock, page, offset, size, flags);
771 }
772 EXPORT_SYMBOL(inet_sendpage);
773
774 int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
775                  size_t size, int flags)
776 {
777         struct sock *sk = sock->sk;
778         int addr_len = 0;
779         int err;
780
781         sock_rps_record_flow(sk);
782
783         err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
784                                    flags & ~MSG_DONTWAIT, &addr_len);
785         if (err >= 0)
786                 msg->msg_namelen = addr_len;
787         return err;
788 }
789 EXPORT_SYMBOL(inet_recvmsg);
790
791 int inet_shutdown(struct socket *sock, int how)
792 {
793         struct sock *sk = sock->sk;
794         int err = 0;
795
796         /* This should really check to make sure
797          * the socket is a TCP socket. (WHY AC...)
798          */
799         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
800                        1->2 bit 2 snds.
801                        2->3 */
802         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
803                 return -EINVAL;
804
805         lock_sock(sk);
806         if (sock->state == SS_CONNECTING) {
807                 if ((1 << sk->sk_state) &
808                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
809                         sock->state = SS_DISCONNECTING;
810                 else
811                         sock->state = SS_CONNECTED;
812         }
813
814         switch (sk->sk_state) {
815         case TCP_CLOSE:
816                 err = -ENOTCONN;
817                 /* Hack to wake up other listeners, who can poll for
818                    POLLHUP, even on eg. unconnected UDP sockets -- RR */
819         default:
820                 sk->sk_shutdown |= how;
821                 if (sk->sk_prot->shutdown)
822                         sk->sk_prot->shutdown(sk, how);
823                 break;
824
825         /* Remaining two branches are temporary solution for missing
826          * close() in multithreaded environment. It is _not_ a good idea,
827          * but we have no choice until close() is repaired at VFS level.
828          */
829         case TCP_LISTEN:
830                 if (!(how & RCV_SHUTDOWN))
831                         break;
832                 /* Fall through */
833         case TCP_SYN_SENT:
834                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
835                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
836                 break;
837         }
838
839         /* Wake up anyone sleeping in poll. */
840         sk->sk_state_change(sk);
841         release_sock(sk);
842         return err;
843 }
844 EXPORT_SYMBOL(inet_shutdown);
845
846 /*
847  *      ioctl() calls you can issue on an INET socket. Most of these are
848  *      device configuration and stuff and very rarely used. Some ioctls
849  *      pass on to the socket itself.
850  *
851  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
852  *      loads the devconfigure module does its configuring and unloads it.
853  *      There's a good 20K of config code hanging around the kernel.
854  */
855
856 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
857 {
858         struct sock *sk = sock->sk;
859         int err = 0;
860         struct net *net = sock_net(sk);
861
862         switch (cmd) {
863         case SIOCGSTAMP:
864                 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
865                 break;
866         case SIOCGSTAMPNS:
867                 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
868                 break;
869         case SIOCADDRT:
870         case SIOCDELRT:
871         case SIOCRTMSG:
872                 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
873                 break;
874         case SIOCDARP:
875         case SIOCGARP:
876         case SIOCSARP:
877                 err = arp_ioctl(net, cmd, (void __user *)arg);
878                 break;
879         case SIOCGIFADDR:
880         case SIOCSIFADDR:
881         case SIOCGIFBRDADDR:
882         case SIOCSIFBRDADDR:
883         case SIOCGIFNETMASK:
884         case SIOCSIFNETMASK:
885         case SIOCGIFDSTADDR:
886         case SIOCSIFDSTADDR:
887         case SIOCSIFPFLAGS:
888         case SIOCGIFPFLAGS:
889         case SIOCSIFFLAGS:
890                 err = devinet_ioctl(net, cmd, (void __user *)arg);
891                 break;
892         default:
893                 if (sk->sk_prot->ioctl)
894                         err = sk->sk_prot->ioctl(sk, cmd, arg);
895                 else
896                         err = -ENOIOCTLCMD;
897                 break;
898         }
899         return err;
900 }
901 EXPORT_SYMBOL(inet_ioctl);
902
903 #ifdef CONFIG_COMPAT
904 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
905 {
906         struct sock *sk = sock->sk;
907         int err = -ENOIOCTLCMD;
908
909         if (sk->sk_prot->compat_ioctl)
910                 err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
911
912         return err;
913 }
914 #endif
915
916 const struct proto_ops inet_stream_ops = {
917         .family            = PF_INET,
918         .owner             = THIS_MODULE,
919         .release           = inet_release,
920         .bind              = inet_bind,
921         .connect           = inet_stream_connect,
922         .socketpair        = sock_no_socketpair,
923         .accept            = inet_accept,
924         .getname           = inet_getname,
925         .poll              = tcp_poll,
926         .ioctl             = inet_ioctl,
927         .listen            = inet_listen,
928         .shutdown          = inet_shutdown,
929         .setsockopt        = sock_common_setsockopt,
930         .getsockopt        = sock_common_getsockopt,
931         .sendmsg           = inet_sendmsg,
932         .recvmsg           = inet_recvmsg,
933         .mmap              = sock_no_mmap,
934         .sendpage          = inet_sendpage,
935         .splice_read       = tcp_splice_read,
936 #ifdef CONFIG_COMPAT
937         .compat_setsockopt = compat_sock_common_setsockopt,
938         .compat_getsockopt = compat_sock_common_getsockopt,
939         .compat_ioctl      = inet_compat_ioctl,
940 #endif
941 };
942 EXPORT_SYMBOL(inet_stream_ops);
943
944 const struct proto_ops inet_dgram_ops = {
945         .family            = PF_INET,
946         .owner             = THIS_MODULE,
947         .release           = inet_release,
948         .bind              = inet_bind,
949         .connect           = inet_dgram_connect,
950         .socketpair        = sock_no_socketpair,
951         .accept            = sock_no_accept,
952         .getname           = inet_getname,
953         .poll              = udp_poll,
954         .ioctl             = inet_ioctl,
955         .listen            = sock_no_listen,
956         .shutdown          = inet_shutdown,
957         .setsockopt        = sock_common_setsockopt,
958         .getsockopt        = sock_common_getsockopt,
959         .sendmsg           = inet_sendmsg,
960         .recvmsg           = inet_recvmsg,
961         .mmap              = sock_no_mmap,
962         .sendpage          = inet_sendpage,
963 #ifdef CONFIG_COMPAT
964         .compat_setsockopt = compat_sock_common_setsockopt,
965         .compat_getsockopt = compat_sock_common_getsockopt,
966         .compat_ioctl      = inet_compat_ioctl,
967 #endif
968 };
969 EXPORT_SYMBOL(inet_dgram_ops);
970
971 /*
972  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
973  * udp_poll
974  */
975 static const struct proto_ops inet_sockraw_ops = {
976         .family            = PF_INET,
977         .owner             = THIS_MODULE,
978         .release           = inet_release,
979         .bind              = inet_bind,
980         .connect           = inet_dgram_connect,
981         .socketpair        = sock_no_socketpair,
982         .accept            = sock_no_accept,
983         .getname           = inet_getname,
984         .poll              = datagram_poll,
985         .ioctl             = inet_ioctl,
986         .listen            = sock_no_listen,
987         .shutdown          = inet_shutdown,
988         .setsockopt        = sock_common_setsockopt,
989         .getsockopt        = sock_common_getsockopt,
990         .sendmsg           = inet_sendmsg,
991         .recvmsg           = inet_recvmsg,
992         .mmap              = sock_no_mmap,
993         .sendpage          = inet_sendpage,
994 #ifdef CONFIG_COMPAT
995         .compat_setsockopt = compat_sock_common_setsockopt,
996         .compat_getsockopt = compat_sock_common_getsockopt,
997         .compat_ioctl      = inet_compat_ioctl,
998 #endif
999 };
1000
1001 static const struct net_proto_family inet_family_ops = {
1002         .family = PF_INET,
1003         .create = inet_create,
1004         .owner  = THIS_MODULE,
1005 };
1006
1007 /* Upon startup we insert all the elements in inetsw_array[] into
1008  * the linked list inetsw.
1009  */
1010 static struct inet_protosw inetsw_array[] =
1011 {
1012         {
1013                 .type =       SOCK_STREAM,
1014                 .protocol =   IPPROTO_TCP,
1015                 .prot =       &tcp_prot,
1016                 .ops =        &inet_stream_ops,
1017                 .no_check =   0,
1018                 .flags =      INET_PROTOSW_PERMANENT |
1019                               INET_PROTOSW_ICSK,
1020         },
1021
1022         {
1023                 .type =       SOCK_DGRAM,
1024                 .protocol =   IPPROTO_UDP,
1025                 .prot =       &udp_prot,
1026                 .ops =        &inet_dgram_ops,
1027                 .no_check =   UDP_CSUM_DEFAULT,
1028                 .flags =      INET_PROTOSW_PERMANENT,
1029        },
1030
1031        {
1032                 .type =       SOCK_DGRAM,
1033                 .protocol =   IPPROTO_ICMP,
1034                 .prot =       &ping_prot,
1035                 .ops =        &inet_dgram_ops,
1036                 .no_check =   UDP_CSUM_DEFAULT,
1037                 .flags =      INET_PROTOSW_REUSE,
1038        },
1039
1040        {
1041                .type =       SOCK_RAW,
1042                .protocol =   IPPROTO_IP,        /* wild card */
1043                .prot =       &raw_prot,
1044                .ops =        &inet_sockraw_ops,
1045                .no_check =   UDP_CSUM_DEFAULT,
1046                .flags =      INET_PROTOSW_REUSE,
1047        }
1048 };
1049
1050 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1051
1052 void inet_register_protosw(struct inet_protosw *p)
1053 {
1054         struct list_head *lh;
1055         struct inet_protosw *answer;
1056         int protocol = p->protocol;
1057         struct list_head *last_perm;
1058
1059         spin_lock_bh(&inetsw_lock);
1060
1061         if (p->type >= SOCK_MAX)
1062                 goto out_illegal;
1063
1064         /* If we are trying to override a permanent protocol, bail. */
1065         answer = NULL;
1066         last_perm = &inetsw[p->type];
1067         list_for_each(lh, &inetsw[p->type]) {
1068                 answer = list_entry(lh, struct inet_protosw, list);
1069
1070                 /* Check only the non-wild match. */
1071                 if (INET_PROTOSW_PERMANENT & answer->flags) {
1072                         if (protocol == answer->protocol)
1073                                 break;
1074                         last_perm = lh;
1075                 }
1076
1077                 answer = NULL;
1078         }
1079         if (answer)
1080                 goto out_permanent;
1081
1082         /* Add the new entry after the last permanent entry if any, so that
1083          * the new entry does not override a permanent entry when matched with
1084          * a wild-card protocol. But it is allowed to override any existing
1085          * non-permanent entry.  This means that when we remove this entry, the
1086          * system automatically returns to the old behavior.
1087          */
1088         list_add_rcu(&p->list, last_perm);
1089 out:
1090         spin_unlock_bh(&inetsw_lock);
1091
1092         return;
1093
1094 out_permanent:
1095         printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1096                protocol);
1097         goto out;
1098
1099 out_illegal:
1100         printk(KERN_ERR
1101                "Ignoring attempt to register invalid socket type %d.\n",
1102                p->type);
1103         goto out;
1104 }
1105 EXPORT_SYMBOL(inet_register_protosw);
1106
1107 void inet_unregister_protosw(struct inet_protosw *p)
1108 {
1109         if (INET_PROTOSW_PERMANENT & p->flags) {
1110                 printk(KERN_ERR
1111                        "Attempt to unregister permanent protocol %d.\n",
1112                        p->protocol);
1113         } else {
1114                 spin_lock_bh(&inetsw_lock);
1115                 list_del_rcu(&p->list);
1116                 spin_unlock_bh(&inetsw_lock);
1117
1118                 synchronize_net();
1119         }
1120 }
1121 EXPORT_SYMBOL(inet_unregister_protosw);
1122
1123 /*
1124  *      Shall we try to damage output packets if routing dev changes?
1125  */
1126
1127 int sysctl_ip_dynaddr __read_mostly;
1128
1129 static int inet_sk_reselect_saddr(struct sock *sk)
1130 {
1131         struct inet_sock *inet = inet_sk(sk);
1132         __be32 old_saddr = inet->inet_saddr;
1133         __be32 daddr = inet->inet_daddr;
1134         struct flowi4 *fl4;
1135         struct rtable *rt;
1136         __be32 new_saddr;
1137         struct ip_options_rcu *inet_opt;
1138
1139         inet_opt = rcu_dereference_protected(inet->inet_opt,
1140                                              sock_owned_by_user(sk));
1141         if (inet_opt && inet_opt->opt.srr)
1142                 daddr = inet_opt->opt.faddr;
1143
1144         /* Query new route. */
1145         fl4 = &inet->cork.fl.u.ip4;
1146         rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1147                               sk->sk_bound_dev_if, sk->sk_protocol,
1148                               inet->inet_sport, inet->inet_dport, sk, false);
1149         if (IS_ERR(rt))
1150                 return PTR_ERR(rt);
1151
1152         sk_setup_caps(sk, &rt->dst);
1153
1154         new_saddr = fl4->saddr;
1155
1156         if (new_saddr == old_saddr)
1157                 return 0;
1158
1159         if (sysctl_ip_dynaddr > 1) {
1160                 printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1161                        __func__, &old_saddr, &new_saddr);
1162         }
1163
1164         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1165
1166         /*
1167          * XXX The only one ugly spot where we need to
1168          * XXX really change the sockets identity after
1169          * XXX it has entered the hashes. -DaveM
1170          *
1171          * Besides that, it does not check for connection
1172          * uniqueness. Wait for troubles.
1173          */
1174         __sk_prot_rehash(sk);
1175         return 0;
1176 }
1177
1178 int inet_sk_rebuild_header(struct sock *sk)
1179 {
1180         struct inet_sock *inet = inet_sk(sk);
1181         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1182         __be32 daddr;
1183         struct ip_options_rcu *inet_opt;
1184         struct flowi4 *fl4;
1185         int err;
1186
1187         /* Route is OK, nothing to do. */
1188         if (rt)
1189                 return 0;
1190
1191         /* Reroute. */
1192         rcu_read_lock();
1193         inet_opt = rcu_dereference(inet->inet_opt);
1194         daddr = inet->inet_daddr;
1195         if (inet_opt && inet_opt->opt.srr)
1196                 daddr = inet_opt->opt.faddr;
1197         rcu_read_unlock();
1198         fl4 = &inet->cork.fl.u.ip4;
1199         rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1200                                    inet->inet_dport, inet->inet_sport,
1201                                    sk->sk_protocol, RT_CONN_FLAGS(sk),
1202                                    sk->sk_bound_dev_if);
1203         if (!IS_ERR(rt)) {
1204                 err = 0;
1205                 sk_setup_caps(sk, &rt->dst);
1206         } else {
1207                 err = PTR_ERR(rt);
1208
1209                 /* Routing failed... */
1210                 sk->sk_route_caps = 0;
1211                 /*
1212                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1213                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1214                  */
1215                 if (!sysctl_ip_dynaddr ||
1216                     sk->sk_state != TCP_SYN_SENT ||
1217                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1218                     (err = inet_sk_reselect_saddr(sk)) != 0)
1219                         sk->sk_err_soft = -err;
1220         }
1221
1222         return err;
1223 }
1224 EXPORT_SYMBOL(inet_sk_rebuild_header);
1225
1226 static int inet_gso_send_check(struct sk_buff *skb)
1227 {
1228         const struct iphdr *iph;
1229         const struct net_protocol *ops;
1230         int proto;
1231         int ihl;
1232         int err = -EINVAL;
1233
1234         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1235                 goto out;
1236
1237         iph = ip_hdr(skb);
1238         ihl = iph->ihl * 4;
1239         if (ihl < sizeof(*iph))
1240                 goto out;
1241
1242         if (unlikely(!pskb_may_pull(skb, ihl)))
1243                 goto out;
1244
1245         __skb_pull(skb, ihl);
1246         skb_reset_transport_header(skb);
1247         iph = ip_hdr(skb);
1248         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1249         err = -EPROTONOSUPPORT;
1250
1251         rcu_read_lock();
1252         ops = rcu_dereference(inet_protos[proto]);
1253         if (likely(ops && ops->gso_send_check))
1254                 err = ops->gso_send_check(skb);
1255         rcu_read_unlock();
1256
1257 out:
1258         return err;
1259 }
1260
1261 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, u32 features)
1262 {
1263         struct sk_buff *segs = ERR_PTR(-EINVAL);
1264         struct iphdr *iph;
1265         const struct net_protocol *ops;
1266         int proto;
1267         int ihl;
1268         int id;
1269         unsigned int offset = 0;
1270
1271         if (!(features & NETIF_F_V4_CSUM))
1272                 features &= ~NETIF_F_SG;
1273
1274         if (unlikely(skb_shinfo(skb)->gso_type &
1275                      ~(SKB_GSO_TCPV4 |
1276                        SKB_GSO_UDP |
1277                        SKB_GSO_DODGY |
1278                        SKB_GSO_TCP_ECN |
1279                        0)))
1280                 goto out;
1281
1282         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1283                 goto out;
1284
1285         iph = ip_hdr(skb);
1286         ihl = iph->ihl * 4;
1287         if (ihl < sizeof(*iph))
1288                 goto out;
1289
1290         if (unlikely(!pskb_may_pull(skb, ihl)))
1291                 goto out;
1292
1293         __skb_pull(skb, ihl);
1294         skb_reset_transport_header(skb);
1295         iph = ip_hdr(skb);
1296         id = ntohs(iph->id);
1297         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1298         segs = ERR_PTR(-EPROTONOSUPPORT);
1299
1300         rcu_read_lock();
1301         ops = rcu_dereference(inet_protos[proto]);
1302         if (likely(ops && ops->gso_segment))
1303                 segs = ops->gso_segment(skb, features);
1304         rcu_read_unlock();
1305
1306         if (!segs || IS_ERR(segs))
1307                 goto out;
1308
1309         skb = segs;
1310         do {
1311                 iph = ip_hdr(skb);
1312                 if (proto == IPPROTO_UDP) {
1313                         iph->id = htons(id);
1314                         iph->frag_off = htons(offset >> 3);
1315                         if (skb->next != NULL)
1316                                 iph->frag_off |= htons(IP_MF);
1317                         offset += (skb->len - skb->mac_len - iph->ihl * 4);
1318                 } else
1319                         iph->id = htons(id++);
1320                 iph->tot_len = htons(skb->len - skb->mac_len);
1321                 iph->check = 0;
1322                 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1323         } while ((skb = skb->next));
1324
1325 out:
1326         return segs;
1327 }
1328
1329 static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1330                                          struct sk_buff *skb)
1331 {
1332         const struct net_protocol *ops;
1333         struct sk_buff **pp = NULL;
1334         struct sk_buff *p;
1335         const struct iphdr *iph;
1336         unsigned int hlen;
1337         unsigned int off;
1338         unsigned int id;
1339         int flush = 1;
1340         int proto;
1341
1342         off = skb_gro_offset(skb);
1343         hlen = off + sizeof(*iph);
1344         iph = skb_gro_header_fast(skb, off);
1345         if (skb_gro_header_hard(skb, hlen)) {
1346                 iph = skb_gro_header_slow(skb, hlen, off);
1347                 if (unlikely(!iph))
1348                         goto out;
1349         }
1350
1351         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1352
1353         rcu_read_lock();
1354         ops = rcu_dereference(inet_protos[proto]);
1355         if (!ops || !ops->gro_receive)
1356                 goto out_unlock;
1357
1358         if (*(u8 *)iph != 0x45)
1359                 goto out_unlock;
1360
1361         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1362                 goto out_unlock;
1363
1364         id = ntohl(*(__be32 *)&iph->id);
1365         flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1366         id >>= 16;
1367
1368         for (p = *head; p; p = p->next) {
1369                 struct iphdr *iph2;
1370
1371                 if (!NAPI_GRO_CB(p)->same_flow)
1372                         continue;
1373
1374                 iph2 = ip_hdr(p);
1375
1376                 if ((iph->protocol ^ iph2->protocol) |
1377                     (iph->tos ^ iph2->tos) |
1378                     ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1379                     ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1380                         NAPI_GRO_CB(p)->same_flow = 0;
1381                         continue;
1382                 }
1383
1384                 /* All fields must match except length and checksum. */
1385                 NAPI_GRO_CB(p)->flush |=
1386                         (iph->ttl ^ iph2->ttl) |
1387                         ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1388
1389                 NAPI_GRO_CB(p)->flush |= flush;
1390         }
1391
1392         NAPI_GRO_CB(skb)->flush |= flush;
1393         skb_gro_pull(skb, sizeof(*iph));
1394         skb_set_transport_header(skb, skb_gro_offset(skb));
1395
1396         pp = ops->gro_receive(head, skb);
1397
1398 out_unlock:
1399         rcu_read_unlock();
1400
1401 out:
1402         NAPI_GRO_CB(skb)->flush |= flush;
1403
1404         return pp;
1405 }
1406
1407 static int inet_gro_complete(struct sk_buff *skb)
1408 {
1409         const struct net_protocol *ops;
1410         struct iphdr *iph = ip_hdr(skb);
1411         int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1412         int err = -ENOSYS;
1413         __be16 newlen = htons(skb->len - skb_network_offset(skb));
1414
1415         csum_replace2(&iph->check, iph->tot_len, newlen);
1416         iph->tot_len = newlen;
1417
1418         rcu_read_lock();
1419         ops = rcu_dereference(inet_protos[proto]);
1420         if (WARN_ON(!ops || !ops->gro_complete))
1421                 goto out_unlock;
1422
1423         err = ops->gro_complete(skb);
1424
1425 out_unlock:
1426         rcu_read_unlock();
1427
1428         return err;
1429 }
1430
1431 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1432                          unsigned short type, unsigned char protocol,
1433                          struct net *net)
1434 {
1435         struct socket *sock;
1436         int rc = sock_create_kern(family, type, protocol, &sock);
1437
1438         if (rc == 0) {
1439                 *sk = sock->sk;
1440                 (*sk)->sk_allocation = GFP_ATOMIC;
1441                 /*
1442                  * Unhash it so that IP input processing does not even see it,
1443                  * we do not wish this socket to see incoming packets.
1444                  */
1445                 (*sk)->sk_prot->unhash(*sk);
1446
1447                 sk_change_net(*sk, net);
1448         }
1449         return rc;
1450 }
1451 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1452
1453 unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1454 {
1455         unsigned long res = 0;
1456         int i, j;
1457
1458         for_each_possible_cpu(i) {
1459                 for (j = 0; j < SNMP_ARRAY_SZ; j++)
1460                         res += *(((unsigned long *) per_cpu_ptr(mib[j], i)) + offt);
1461         }
1462         return res;
1463 }
1464 EXPORT_SYMBOL_GPL(snmp_fold_field);
1465
1466 #if BITS_PER_LONG==32
1467
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[0], cpu);
1480                 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1481                 do {
1482                         start = u64_stats_fetch_begin_bh(syncp);
1483                         v = *(((u64 *) bhptr) + offt);
1484                 } while (u64_stats_fetch_retry_bh(syncp, start));
1485
1486                 res += v;
1487         }
1488         return res;
1489 }
1490 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1491 #endif
1492
1493 int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align)
1494 {
1495         BUG_ON(ptr == NULL);
1496         ptr[0] = __alloc_percpu(mibsize, align);
1497         if (!ptr[0])
1498                 return -ENOMEM;
1499 #if SNMP_ARRAY_SZ == 2
1500         ptr[1] = __alloc_percpu(mibsize, align);
1501         if (!ptr[1]) {
1502                 free_percpu(ptr[0]);
1503                 ptr[0] = NULL;
1504                 return -ENOMEM;
1505         }
1506 #endif
1507         return 0;
1508 }
1509 EXPORT_SYMBOL_GPL(snmp_mib_init);
1510
1511 void snmp_mib_free(void __percpu *ptr[SNMP_ARRAY_SZ])
1512 {
1513         int i;
1514
1515         BUG_ON(ptr == NULL);
1516         for (i = 0; i < SNMP_ARRAY_SZ; i++) {
1517                 free_percpu(ptr[i]);
1518                 ptr[i] = NULL;
1519         }
1520 }
1521 EXPORT_SYMBOL_GPL(snmp_mib_free);
1522
1523 #ifdef CONFIG_IP_MULTICAST
1524 static const struct net_protocol igmp_protocol = {
1525         .handler =      igmp_rcv,
1526         .netns_ok =     1,
1527 };
1528 #endif
1529
1530 static const struct net_protocol tcp_protocol = {
1531         .handler =      tcp_v4_rcv,
1532         .err_handler =  tcp_v4_err,
1533         .gso_send_check = tcp_v4_gso_send_check,
1534         .gso_segment =  tcp_tso_segment,
1535         .gro_receive =  tcp4_gro_receive,
1536         .gro_complete = tcp4_gro_complete,
1537         .no_policy =    1,
1538         .netns_ok =     1,
1539 };
1540
1541 static const struct net_protocol udp_protocol = {
1542         .handler =      udp_rcv,
1543         .err_handler =  udp_err,
1544         .gso_send_check = udp4_ufo_send_check,
1545         .gso_segment = udp4_ufo_fragment,
1546         .no_policy =    1,
1547         .netns_ok =     1,
1548 };
1549
1550 static const struct net_protocol icmp_protocol = {
1551         .handler =      icmp_rcv,
1552         .err_handler =  ping_err,
1553         .no_policy =    1,
1554         .netns_ok =     1,
1555 };
1556
1557 static __net_init int ipv4_mib_init_net(struct net *net)
1558 {
1559         if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1560                           sizeof(struct tcp_mib),
1561                           __alignof__(struct tcp_mib)) < 0)
1562                 goto err_tcp_mib;
1563         if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1564                           sizeof(struct ipstats_mib),
1565                           __alignof__(struct ipstats_mib)) < 0)
1566                 goto err_ip_mib;
1567         if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1568                           sizeof(struct linux_mib),
1569                           __alignof__(struct linux_mib)) < 0)
1570                 goto err_net_mib;
1571         if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1572                           sizeof(struct udp_mib),
1573                           __alignof__(struct udp_mib)) < 0)
1574                 goto err_udp_mib;
1575         if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1576                           sizeof(struct udp_mib),
1577                           __alignof__(struct udp_mib)) < 0)
1578                 goto err_udplite_mib;
1579         if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1580                           sizeof(struct icmp_mib),
1581                           __alignof__(struct icmp_mib)) < 0)
1582                 goto err_icmp_mib;
1583         if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1584                           sizeof(struct icmpmsg_mib),
1585                           __alignof__(struct icmpmsg_mib)) < 0)
1586                 goto err_icmpmsg_mib;
1587
1588         tcp_mib_init(net);
1589         return 0;
1590
1591 err_icmpmsg_mib:
1592         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1593 err_icmp_mib:
1594         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1595 err_udplite_mib:
1596         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1597 err_udp_mib:
1598         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1599 err_net_mib:
1600         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1601 err_ip_mib:
1602         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1603 err_tcp_mib:
1604         return -ENOMEM;
1605 }
1606
1607 static __net_exit void ipv4_mib_exit_net(struct net *net)
1608 {
1609         snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
1610         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1611         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1612         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1613         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1614         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1615         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1616 }
1617
1618 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1619         .init = ipv4_mib_init_net,
1620         .exit = ipv4_mib_exit_net,
1621 };
1622
1623 static int __init init_ipv4_mibs(void)
1624 {
1625         return register_pernet_subsys(&ipv4_mib_ops);
1626 }
1627
1628 static int ipv4_proc_init(void);
1629
1630 /*
1631  *      IP protocol layer initialiser
1632  */
1633
1634 static struct packet_type ip_packet_type __read_mostly = {
1635         .type = cpu_to_be16(ETH_P_IP),
1636         .func = ip_rcv,
1637         .gso_send_check = inet_gso_send_check,
1638         .gso_segment = inet_gso_segment,
1639         .gro_receive = inet_gro_receive,
1640         .gro_complete = inet_gro_complete,
1641 };
1642
1643 static int __init inet_init(void)
1644 {
1645         struct sk_buff *dummy_skb;
1646         struct inet_protosw *q;
1647         struct list_head *r;
1648         int rc = -EINVAL;
1649
1650         BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1651
1652         sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1653         if (!sysctl_local_reserved_ports)
1654                 goto out;
1655
1656         rc = proto_register(&tcp_prot, 1);
1657         if (rc)
1658                 goto out_free_reserved_ports;
1659
1660         rc = proto_register(&udp_prot, 1);
1661         if (rc)
1662                 goto out_unregister_tcp_proto;
1663
1664         rc = proto_register(&raw_prot, 1);
1665         if (rc)
1666                 goto out_unregister_udp_proto;
1667
1668         rc = proto_register(&ping_prot, 1);
1669         if (rc)
1670                 goto out_unregister_raw_proto;
1671
1672         /*
1673          *      Tell SOCKET that we are alive...
1674          */
1675
1676         (void)sock_register(&inet_family_ops);
1677
1678 #ifdef CONFIG_SYSCTL
1679         ip_static_sysctl_init();
1680 #endif
1681
1682         /*
1683          *      Add all the base protocols.
1684          */
1685
1686         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1687                 printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1688         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1689                 printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1690         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1691                 printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1692 #ifdef CONFIG_IP_MULTICAST
1693         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1694                 printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1695 #endif
1696
1697         /* Register the socket-side information for inet_create. */
1698         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1699                 INIT_LIST_HEAD(r);
1700
1701         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1702                 inet_register_protosw(q);
1703
1704         /*
1705          *      Set the ARP module up
1706          */
1707
1708         arp_init();
1709
1710         /*
1711          *      Set the IP module up
1712          */
1713
1714         ip_init();
1715
1716         tcp_v4_init();
1717
1718         /* Setup TCP slab cache for open requests. */
1719         tcp_init();
1720
1721         /* Setup UDP memory threshold */
1722         udp_init();
1723
1724         /* Add UDP-Lite (RFC 3828) */
1725         udplite4_register();
1726
1727         ping_init();
1728
1729         /*
1730          *      Set the ICMP layer up
1731          */
1732
1733         if (icmp_init() < 0)
1734                 panic("Failed to create the ICMP control socket.\n");
1735
1736         /*
1737          *      Initialise the multicast router
1738          */
1739 #if defined(CONFIG_IP_MROUTE)
1740         if (ip_mr_init())
1741                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1742 #endif
1743         /*
1744          *      Initialise per-cpu ipv4 mibs
1745          */
1746
1747         if (init_ipv4_mibs())
1748                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1749
1750         ipv4_proc_init();
1751
1752         ipfrag_init();
1753
1754         dev_add_pack(&ip_packet_type);
1755
1756         rc = 0;
1757 out:
1758         return rc;
1759 out_unregister_raw_proto:
1760         proto_unregister(&raw_prot);
1761 out_unregister_udp_proto:
1762         proto_unregister(&udp_prot);
1763 out_unregister_tcp_proto:
1764         proto_unregister(&tcp_prot);
1765 out_free_reserved_ports:
1766         kfree(sysctl_local_reserved_ports);
1767         goto out;
1768 }
1769
1770 fs_initcall(inet_init);
1771
1772 /* ------------------------------------------------------------------------ */
1773
1774 #ifdef CONFIG_PROC_FS
1775 static int __init ipv4_proc_init(void)
1776 {
1777         int rc = 0;
1778
1779         if (raw_proc_init())
1780                 goto out_raw;
1781         if (tcp4_proc_init())
1782                 goto out_tcp;
1783         if (udp4_proc_init())
1784                 goto out_udp;
1785         if (ping_proc_init())
1786                 goto out_ping;
1787         if (ip_misc_proc_init())
1788                 goto out_misc;
1789 out:
1790         return rc;
1791 out_misc:
1792         ping_proc_exit();
1793 out_ping:
1794         udp4_proc_exit();
1795 out_udp:
1796         tcp4_proc_exit();
1797 out_tcp:
1798         raw_proc_exit();
1799 out_raw:
1800         rc = -ENOMEM;
1801         goto out;
1802 }
1803
1804 #else /* CONFIG_PROC_FS */
1805 static int __init ipv4_proc_init(void)
1806 {
1807         return 0;
1808 }
1809 #endif /* CONFIG_PROC_FS */
1810
1811 MODULE_ALIAS_NETPROTO(PF_INET);
1812