devinet_ioctl(): take copyin/copyout to caller
[muen/linux.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 #define pr_fmt(fmt) "IPv4: " fmt
69
70 #include <linux/err.h>
71 #include <linux/errno.h>
72 #include <linux/types.h>
73 #include <linux/socket.h>
74 #include <linux/in.h>
75 #include <linux/kernel.h>
76 #include <linux/kmod.h>
77 #include <linux/sched.h>
78 #include <linux/timer.h>
79 #include <linux/string.h>
80 #include <linux/sockios.h>
81 #include <linux/net.h>
82 #include <linux/capability.h>
83 #include <linux/fcntl.h>
84 #include <linux/mm.h>
85 #include <linux/interrupt.h>
86 #include <linux/stat.h>
87 #include <linux/init.h>
88 #include <linux/poll.h>
89 #include <linux/netfilter_ipv4.h>
90 #include <linux/random.h>
91 #include <linux/slab.h>
92
93 #include <linux/uaccess.h>
94
95 #include <linux/inet.h>
96 #include <linux/igmp.h>
97 #include <linux/inetdevice.h>
98 #include <linux/netdevice.h>
99 #include <net/checksum.h>
100 #include <net/ip.h>
101 #include <net/protocol.h>
102 #include <net/arp.h>
103 #include <net/route.h>
104 #include <net/ip_fib.h>
105 #include <net/inet_connection_sock.h>
106 #include <net/tcp.h>
107 #include <net/udp.h>
108 #include <net/udplite.h>
109 #include <net/ping.h>
110 #include <linux/skbuff.h>
111 #include <net/sock.h>
112 #include <net/raw.h>
113 #include <net/icmp.h>
114 #include <net/inet_common.h>
115 #include <net/ip_tunnels.h>
116 #include <net/xfrm.h>
117 #include <net/net_namespace.h>
118 #include <net/secure_seq.h>
119 #ifdef CONFIG_IP_MROUTE
120 #include <linux/mroute.h>
121 #endif
122 #include <net/l3mdev.h>
123
124 #include <trace/events/sock.h>
125
126 /* The inetsw table contains everything that inet_create needs to
127  * build a new socket.
128  */
129 static struct list_head inetsw[SOCK_MAX];
130 static DEFINE_SPINLOCK(inetsw_lock);
131
132 /* New destruction routine */
133
134 void inet_sock_destruct(struct sock *sk)
135 {
136         struct inet_sock *inet = inet_sk(sk);
137
138         __skb_queue_purge(&sk->sk_receive_queue);
139         __skb_queue_purge(&sk->sk_error_queue);
140
141         sk_mem_reclaim(sk);
142
143         if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
144                 pr_err("Attempt to release TCP socket in state %d %p\n",
145                        sk->sk_state, sk);
146                 return;
147         }
148         if (!sock_flag(sk, SOCK_DEAD)) {
149                 pr_err("Attempt to release alive inet socket %p\n", sk);
150                 return;
151         }
152
153         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
154         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
155         WARN_ON(sk->sk_wmem_queued);
156         WARN_ON(sk->sk_forward_alloc);
157
158         kfree(rcu_dereference_protected(inet->inet_opt, 1));
159         dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
160         dst_release(sk->sk_rx_dst);
161         sk_refcnt_debug_dec(sk);
162 }
163 EXPORT_SYMBOL(inet_sock_destruct);
164
165 /*
166  *      The routines beyond this point handle the behaviour of an AF_INET
167  *      socket object. Mostly it punts to the subprotocols of IP to do
168  *      the work.
169  */
170
171 /*
172  *      Automatically bind an unbound socket.
173  */
174
175 static int inet_autobind(struct sock *sk)
176 {
177         struct inet_sock *inet;
178         /* We may need to bind the socket. */
179         lock_sock(sk);
180         inet = inet_sk(sk);
181         if (!inet->inet_num) {
182                 if (sk->sk_prot->get_port(sk, 0)) {
183                         release_sock(sk);
184                         return -EAGAIN;
185                 }
186                 inet->inet_sport = htons(inet->inet_num);
187         }
188         release_sock(sk);
189         return 0;
190 }
191
192 /*
193  *      Move a socket into listening state.
194  */
195 int inet_listen(struct socket *sock, int backlog)
196 {
197         struct sock *sk = sock->sk;
198         unsigned char old_state;
199         int err, tcp_fastopen;
200
201         lock_sock(sk);
202
203         err = -EINVAL;
204         if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
205                 goto out;
206
207         old_state = sk->sk_state;
208         if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
209                 goto out;
210
211         /* Really, if the socket is already in listen state
212          * we can only allow the backlog to be adjusted.
213          */
214         if (old_state != TCP_LISTEN) {
215                 /* Enable TFO w/o requiring TCP_FASTOPEN socket option.
216                  * Note that only TCP sockets (SOCK_STREAM) will reach here.
217                  * Also fastopen backlog may already been set via the option
218                  * because the socket was in TCP_LISTEN state previously but
219                  * was shutdown() rather than close().
220                  */
221                 tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen;
222                 if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) &&
223                     (tcp_fastopen & TFO_SERVER_ENABLE) &&
224                     !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) {
225                         fastopen_queue_tune(sk, backlog);
226                         tcp_fastopen_init_key_once(sock_net(sk));
227                 }
228
229                 err = inet_csk_listen_start(sk, backlog);
230                 if (err)
231                         goto out;
232         }
233         sk->sk_max_ack_backlog = backlog;
234         err = 0;
235
236 out:
237         release_sock(sk);
238         return err;
239 }
240 EXPORT_SYMBOL(inet_listen);
241
242 /*
243  *      Create an inet socket.
244  */
245
246 static int inet_create(struct net *net, struct socket *sock, int protocol,
247                        int kern)
248 {
249         struct sock *sk;
250         struct inet_protosw *answer;
251         struct inet_sock *inet;
252         struct proto *answer_prot;
253         unsigned char answer_flags;
254         int try_loading_module = 0;
255         int err;
256
257         if (protocol < 0 || protocol >= IPPROTO_MAX)
258                 return -EINVAL;
259
260         sock->state = SS_UNCONNECTED;
261
262         /* Look for the requested type/protocol pair. */
263 lookup_protocol:
264         err = -ESOCKTNOSUPPORT;
265         rcu_read_lock();
266         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
267
268                 err = 0;
269                 /* Check the non-wild match. */
270                 if (protocol == answer->protocol) {
271                         if (protocol != IPPROTO_IP)
272                                 break;
273                 } else {
274                         /* Check for the two wild cases. */
275                         if (IPPROTO_IP == protocol) {
276                                 protocol = answer->protocol;
277                                 break;
278                         }
279                         if (IPPROTO_IP == answer->protocol)
280                                 break;
281                 }
282                 err = -EPROTONOSUPPORT;
283         }
284
285         if (unlikely(err)) {
286                 if (try_loading_module < 2) {
287                         rcu_read_unlock();
288                         /*
289                          * Be more specific, e.g. net-pf-2-proto-132-type-1
290                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
291                          */
292                         if (++try_loading_module == 1)
293                                 request_module("net-pf-%d-proto-%d-type-%d",
294                                                PF_INET, protocol, sock->type);
295                         /*
296                          * Fall back to generic, e.g. net-pf-2-proto-132
297                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
298                          */
299                         else
300                                 request_module("net-pf-%d-proto-%d",
301                                                PF_INET, protocol);
302                         goto lookup_protocol;
303                 } else
304                         goto out_rcu_unlock;
305         }
306
307         err = -EPERM;
308         if (sock->type == SOCK_RAW && !kern &&
309             !ns_capable(net->user_ns, CAP_NET_RAW))
310                 goto out_rcu_unlock;
311
312         sock->ops = answer->ops;
313         answer_prot = answer->prot;
314         answer_flags = answer->flags;
315         rcu_read_unlock();
316
317         WARN_ON(!answer_prot->slab);
318
319         err = -ENOBUFS;
320         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern);
321         if (!sk)
322                 goto out;
323
324         err = 0;
325         if (INET_PROTOSW_REUSE & answer_flags)
326                 sk->sk_reuse = SK_CAN_REUSE;
327
328         inet = inet_sk(sk);
329         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
330
331         inet->nodefrag = 0;
332
333         if (SOCK_RAW == sock->type) {
334                 inet->inet_num = protocol;
335                 if (IPPROTO_RAW == protocol)
336                         inet->hdrincl = 1;
337         }
338
339         if (net->ipv4.sysctl_ip_no_pmtu_disc)
340                 inet->pmtudisc = IP_PMTUDISC_DONT;
341         else
342                 inet->pmtudisc = IP_PMTUDISC_WANT;
343
344         inet->inet_id = 0;
345
346         sock_init_data(sock, sk);
347
348         sk->sk_destruct    = inet_sock_destruct;
349         sk->sk_protocol    = protocol;
350         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
351
352         inet->uc_ttl    = -1;
353         inet->mc_loop   = 1;
354         inet->mc_ttl    = 1;
355         inet->mc_all    = 1;
356         inet->mc_index  = 0;
357         inet->mc_list   = NULL;
358         inet->rcv_tos   = 0;
359
360         sk_refcnt_debug_inc(sk);
361
362         if (inet->inet_num) {
363                 /* It assumes that any protocol which allows
364                  * the user to assign a number at socket
365                  * creation time automatically
366                  * shares.
367                  */
368                 inet->inet_sport = htons(inet->inet_num);
369                 /* Add to protocol hash chains. */
370                 err = sk->sk_prot->hash(sk);
371                 if (err) {
372                         sk_common_release(sk);
373                         goto out;
374                 }
375         }
376
377         if (sk->sk_prot->init) {
378                 err = sk->sk_prot->init(sk);
379                 if (err) {
380                         sk_common_release(sk);
381                         goto out;
382                 }
383         }
384
385         if (!kern) {
386                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
387                 if (err) {
388                         sk_common_release(sk);
389                         goto out;
390                 }
391         }
392 out:
393         return err;
394 out_rcu_unlock:
395         rcu_read_unlock();
396         goto out;
397 }
398
399
400 /*
401  *      The peer socket should always be NULL (or else). When we call this
402  *      function we are destroying the object and from then on nobody
403  *      should refer to it.
404  */
405 int inet_release(struct socket *sock)
406 {
407         struct sock *sk = sock->sk;
408
409         if (sk) {
410                 long timeout;
411
412                 /* Applications forget to leave groups before exiting */
413                 ip_mc_drop_socket(sk);
414
415                 /* If linger is set, we don't return until the close
416                  * is complete.  Otherwise we return immediately. The
417                  * actually closing is done the same either way.
418                  *
419                  * If the close is due to the process exiting, we never
420                  * linger..
421                  */
422                 timeout = 0;
423                 if (sock_flag(sk, SOCK_LINGER) &&
424                     !(current->flags & PF_EXITING))
425                         timeout = sk->sk_lingertime;
426                 sock->sk = NULL;
427                 sk->sk_prot->close(sk, timeout);
428         }
429         return 0;
430 }
431 EXPORT_SYMBOL(inet_release);
432
433 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
434 {
435         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
436         struct sock *sk = sock->sk;
437         struct inet_sock *inet = inet_sk(sk);
438         struct net *net = sock_net(sk);
439         unsigned short snum;
440         int chk_addr_ret;
441         u32 tb_id = RT_TABLE_LOCAL;
442         int err;
443
444         /* If the socket has its own bind function then use it. (RAW) */
445         if (sk->sk_prot->bind) {
446                 err = sk->sk_prot->bind(sk, uaddr, addr_len);
447                 goto out;
448         }
449         err = -EINVAL;
450         if (addr_len < sizeof(struct sockaddr_in))
451                 goto out;
452
453         if (addr->sin_family != AF_INET) {
454                 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
455                  * only if s_addr is INADDR_ANY.
456                  */
457                 err = -EAFNOSUPPORT;
458                 if (addr->sin_family != AF_UNSPEC ||
459                     addr->sin_addr.s_addr != htonl(INADDR_ANY))
460                         goto out;
461         }
462
463         tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
464         chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
465
466         /* Not specified by any standard per-se, however it breaks too
467          * many applications when removed.  It is unfortunate since
468          * allowing applications to make a non-local bind solves
469          * several problems with systems using dynamic addressing.
470          * (ie. your servers still start up even if your ISDN link
471          *  is temporarily down)
472          */
473         err = -EADDRNOTAVAIL;
474         if (!net->ipv4.sysctl_ip_nonlocal_bind &&
475             !(inet->freebind || inet->transparent) &&
476             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
477             chk_addr_ret != RTN_LOCAL &&
478             chk_addr_ret != RTN_MULTICAST &&
479             chk_addr_ret != RTN_BROADCAST)
480                 goto out;
481
482         snum = ntohs(addr->sin_port);
483         err = -EACCES;
484         if (snum && snum < inet_prot_sock(net) &&
485             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
486                 goto out;
487
488         /*      We keep a pair of addresses. rcv_saddr is the one
489          *      used by hash lookups, and saddr is used for transmit.
490          *
491          *      In the BSD API these are the same except where it
492          *      would be illegal to use them (multicast/broadcast) in
493          *      which case the sending device address is used.
494          */
495         lock_sock(sk);
496
497         /* Check these errors (active socket, double bind). */
498         err = -EINVAL;
499         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
500                 goto out_release_sock;
501
502         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
503         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
504                 inet->inet_saddr = 0;  /* Use device */
505
506         /* Make sure we are allowed to bind here. */
507         if ((snum || !inet->bind_address_no_port) &&
508             sk->sk_prot->get_port(sk, snum)) {
509                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
510                 err = -EADDRINUSE;
511                 goto out_release_sock;
512         }
513
514         if (inet->inet_rcv_saddr)
515                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
516         if (snum)
517                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
518         inet->inet_sport = htons(inet->inet_num);
519         inet->inet_daddr = 0;
520         inet->inet_dport = 0;
521         sk_dst_reset(sk);
522         err = 0;
523 out_release_sock:
524         release_sock(sk);
525 out:
526         return err;
527 }
528 EXPORT_SYMBOL(inet_bind);
529
530 int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
531                        int addr_len, int flags)
532 {
533         struct sock *sk = sock->sk;
534
535         if (addr_len < sizeof(uaddr->sa_family))
536                 return -EINVAL;
537         if (uaddr->sa_family == AF_UNSPEC)
538                 return sk->sk_prot->disconnect(sk, flags);
539
540         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
541                 return -EAGAIN;
542         return sk->sk_prot->connect(sk, uaddr, addr_len);
543 }
544 EXPORT_SYMBOL(inet_dgram_connect);
545
546 static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
547 {
548         DEFINE_WAIT_FUNC(wait, woken_wake_function);
549
550         add_wait_queue(sk_sleep(sk), &wait);
551         sk->sk_write_pending += writebias;
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 = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
561                 lock_sock(sk);
562                 if (signal_pending(current) || !timeo)
563                         break;
564         }
565         remove_wait_queue(sk_sleep(sk), &wait);
566         sk->sk_write_pending -= writebias;
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, int is_sendmsg)
576 {
577         struct sock *sk = sock->sk;
578         int err;
579         long timeo;
580
581         /*
582          * uaddr can be NULL and addr_len can be 0 if:
583          * sk is a TCP fastopen active socket and
584          * TCP_FASTOPEN_CONNECT sockopt is set and
585          * we already have a valid cookie for this socket.
586          * In this case, user can call write() after connect().
587          * write() will invoke tcp_sendmsg_fastopen() which calls
588          * __inet_stream_connect().
589          */
590         if (uaddr) {
591                 if (addr_len < sizeof(uaddr->sa_family))
592                         return -EINVAL;
593
594                 if (uaddr->sa_family == AF_UNSPEC) {
595                         err = sk->sk_prot->disconnect(sk, flags);
596                         sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
597                         goto out;
598                 }
599         }
600
601         switch (sock->state) {
602         default:
603                 err = -EINVAL;
604                 goto out;
605         case SS_CONNECTED:
606                 err = -EISCONN;
607                 goto out;
608         case SS_CONNECTING:
609                 if (inet_sk(sk)->defer_connect)
610                         err = is_sendmsg ? -EINPROGRESS : -EISCONN;
611                 else
612                         err = -EALREADY;
613                 /* Fall out of switch with err, set for this state */
614                 break;
615         case SS_UNCONNECTED:
616                 err = -EISCONN;
617                 if (sk->sk_state != TCP_CLOSE)
618                         goto out;
619
620                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
621                 if (err < 0)
622                         goto out;
623
624                 sock->state = SS_CONNECTING;
625
626                 if (!err && inet_sk(sk)->defer_connect)
627                         goto out;
628
629                 /* Just entered SS_CONNECTING state; the only
630                  * difference is that return value in non-blocking
631                  * case is EINPROGRESS, rather than EALREADY.
632                  */
633                 err = -EINPROGRESS;
634                 break;
635         }
636
637         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
638
639         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
640                 int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
641                                 tcp_sk(sk)->fastopen_req &&
642                                 tcp_sk(sk)->fastopen_req->data ? 1 : 0;
643
644                 /* Error code is set above */
645                 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
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         return err;
668
669 sock_error:
670         err = sock_error(sk) ? : -ECONNABORTED;
671         sock->state = SS_UNCONNECTED;
672         if (sk->sk_prot->disconnect(sk, flags))
673                 sock->state = SS_DISCONNECTING;
674         goto out;
675 }
676 EXPORT_SYMBOL(__inet_stream_connect);
677
678 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
679                         int addr_len, int flags)
680 {
681         int err;
682
683         lock_sock(sock->sk);
684         err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0);
685         release_sock(sock->sk);
686         return err;
687 }
688 EXPORT_SYMBOL(inet_stream_connect);
689
690 /*
691  *      Accept a pending connection. The TCP layer now gives BSD semantics.
692  */
693
694 int inet_accept(struct socket *sock, struct socket *newsock, int flags,
695                 bool kern)
696 {
697         struct sock *sk1 = sock->sk;
698         int err = -EINVAL;
699         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern);
700
701         if (!sk2)
702                 goto do_err;
703
704         lock_sock(sk2);
705
706         sock_rps_record_flow(sk2);
707         WARN_ON(!((1 << sk2->sk_state) &
708                   (TCPF_ESTABLISHED | TCPF_SYN_RECV |
709                   TCPF_CLOSE_WAIT | TCPF_CLOSE)));
710
711         sock_graft(sk2, newsock);
712
713         newsock->state = SS_CONNECTED;
714         err = 0;
715         release_sock(sk2);
716 do_err:
717         return err;
718 }
719 EXPORT_SYMBOL(inet_accept);
720
721
722 /*
723  *      This does both peername and sockname.
724  */
725 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
726                         int *uaddr_len, int peer)
727 {
728         struct sock *sk         = sock->sk;
729         struct inet_sock *inet  = inet_sk(sk);
730         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
731
732         sin->sin_family = AF_INET;
733         if (peer) {
734                 if (!inet->inet_dport ||
735                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
736                      peer == 1))
737                         return -ENOTCONN;
738                 sin->sin_port = inet->inet_dport;
739                 sin->sin_addr.s_addr = inet->inet_daddr;
740         } else {
741                 __be32 addr = inet->inet_rcv_saddr;
742                 if (!addr)
743                         addr = inet->inet_saddr;
744                 sin->sin_port = inet->inet_sport;
745                 sin->sin_addr.s_addr = addr;
746         }
747         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
748         *uaddr_len = sizeof(*sin);
749         return 0;
750 }
751 EXPORT_SYMBOL(inet_getname);
752
753 int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
754 {
755         struct sock *sk = sock->sk;
756
757         sock_rps_record_flow(sk);
758
759         /* We may need to bind the socket. */
760         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
761             inet_autobind(sk))
762                 return -EAGAIN;
763
764         return sk->sk_prot->sendmsg(sk, msg, size);
765 }
766 EXPORT_SYMBOL(inet_sendmsg);
767
768 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
769                       size_t size, int flags)
770 {
771         struct sock *sk = sock->sk;
772
773         sock_rps_record_flow(sk);
774
775         /* We may need to bind the socket. */
776         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
777             inet_autobind(sk))
778                 return -EAGAIN;
779
780         if (sk->sk_prot->sendpage)
781                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
782         return sock_no_sendpage(sock, page, offset, size, flags);
783 }
784 EXPORT_SYMBOL(inet_sendpage);
785
786 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
787                  int flags)
788 {
789         struct sock *sk = sock->sk;
790         int addr_len = 0;
791         int err;
792
793         if (likely(!(flags & MSG_ERRQUEUE)))
794                 sock_rps_record_flow(sk);
795
796         err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
797                                    flags & ~MSG_DONTWAIT, &addr_len);
798         if (err >= 0)
799                 msg->msg_namelen = addr_len;
800         return err;
801 }
802 EXPORT_SYMBOL(inet_recvmsg);
803
804 int inet_shutdown(struct socket *sock, int how)
805 {
806         struct sock *sk = sock->sk;
807         int err = 0;
808
809         /* This should really check to make sure
810          * the socket is a TCP socket. (WHY AC...)
811          */
812         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
813                        1->2 bit 2 snds.
814                        2->3 */
815         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
816                 return -EINVAL;
817
818         lock_sock(sk);
819         if (sock->state == SS_CONNECTING) {
820                 if ((1 << sk->sk_state) &
821                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
822                         sock->state = SS_DISCONNECTING;
823                 else
824                         sock->state = SS_CONNECTED;
825         }
826
827         switch (sk->sk_state) {
828         case TCP_CLOSE:
829                 err = -ENOTCONN;
830                 /* Hack to wake up other listeners, who can poll for
831                    POLLHUP, even on eg. unconnected UDP sockets -- RR */
832                 /* fall through */
833         default:
834                 sk->sk_shutdown |= how;
835                 if (sk->sk_prot->shutdown)
836                         sk->sk_prot->shutdown(sk, how);
837                 break;
838
839         /* Remaining two branches are temporary solution for missing
840          * close() in multithreaded environment. It is _not_ a good idea,
841          * but we have no choice until close() is repaired at VFS level.
842          */
843         case TCP_LISTEN:
844                 if (!(how & RCV_SHUTDOWN))
845                         break;
846                 /* fall through */
847         case TCP_SYN_SENT:
848                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
849                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
850                 break;
851         }
852
853         /* Wake up anyone sleeping in poll. */
854         sk->sk_state_change(sk);
855         release_sock(sk);
856         return err;
857 }
858 EXPORT_SYMBOL(inet_shutdown);
859
860 /*
861  *      ioctl() calls you can issue on an INET socket. Most of these are
862  *      device configuration and stuff and very rarely used. Some ioctls
863  *      pass on to the socket itself.
864  *
865  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
866  *      loads the devconfigure module does its configuring and unloads it.
867  *      There's a good 20K of config code hanging around the kernel.
868  */
869
870 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
871 {
872         struct sock *sk = sock->sk;
873         int err = 0;
874         struct net *net = sock_net(sk);
875         void __user *p = (void __user *)arg;
876         struct ifreq ifr;
877
878         switch (cmd) {
879         case SIOCGSTAMP:
880                 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
881                 break;
882         case SIOCGSTAMPNS:
883                 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
884                 break;
885         case SIOCADDRT:
886         case SIOCDELRT:
887         case SIOCRTMSG:
888                 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
889                 break;
890         case SIOCDARP:
891         case SIOCGARP:
892         case SIOCSARP:
893                 err = arp_ioctl(net, cmd, (void __user *)arg);
894                 break;
895         case SIOCGIFADDR:
896         case SIOCGIFBRDADDR:
897         case SIOCGIFNETMASK:
898         case SIOCGIFDSTADDR:
899         case SIOCGIFPFLAGS:
900                 if (copy_from_user(&ifr, p, sizeof(struct ifreq)))
901                         return -EFAULT;
902                 err = devinet_ioctl(net, cmd, &ifr);
903                 if (!err && copy_to_user(p, &ifr, sizeof(struct ifreq)))
904                         err = -EFAULT;
905                 break;
906
907         case SIOCSIFADDR:
908         case SIOCSIFBRDADDR:
909         case SIOCSIFNETMASK:
910         case SIOCSIFDSTADDR:
911         case SIOCSIFPFLAGS:
912         case SIOCSIFFLAGS:
913                 if (copy_from_user(&ifr, p, sizeof(struct ifreq)))
914                         return -EFAULT;
915                 err = devinet_ioctl(net, cmd, &ifr);
916                 break;
917         default:
918                 if (sk->sk_prot->ioctl)
919                         err = sk->sk_prot->ioctl(sk, cmd, arg);
920                 else
921                         err = -ENOIOCTLCMD;
922                 break;
923         }
924         return err;
925 }
926 EXPORT_SYMBOL(inet_ioctl);
927
928 #ifdef CONFIG_COMPAT
929 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
930 {
931         struct sock *sk = sock->sk;
932         int err = -ENOIOCTLCMD;
933
934         if (sk->sk_prot->compat_ioctl)
935                 err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
936
937         return err;
938 }
939 #endif
940
941 const struct proto_ops inet_stream_ops = {
942         .family            = PF_INET,
943         .owner             = THIS_MODULE,
944         .release           = inet_release,
945         .bind              = inet_bind,
946         .connect           = inet_stream_connect,
947         .socketpair        = sock_no_socketpair,
948         .accept            = inet_accept,
949         .getname           = inet_getname,
950         .poll              = tcp_poll,
951         .ioctl             = inet_ioctl,
952         .listen            = inet_listen,
953         .shutdown          = inet_shutdown,
954         .setsockopt        = sock_common_setsockopt,
955         .getsockopt        = sock_common_getsockopt,
956         .sendmsg           = inet_sendmsg,
957         .recvmsg           = inet_recvmsg,
958         .mmap              = sock_no_mmap,
959         .sendpage          = inet_sendpage,
960         .splice_read       = tcp_splice_read,
961         .read_sock         = tcp_read_sock,
962         .sendmsg_locked    = tcp_sendmsg_locked,
963         .sendpage_locked   = tcp_sendpage_locked,
964         .peek_len          = tcp_peek_len,
965 #ifdef CONFIG_COMPAT
966         .compat_setsockopt = compat_sock_common_setsockopt,
967         .compat_getsockopt = compat_sock_common_getsockopt,
968         .compat_ioctl      = inet_compat_ioctl,
969 #endif
970 };
971 EXPORT_SYMBOL(inet_stream_ops);
972
973 const struct proto_ops inet_dgram_ops = {
974         .family            = PF_INET,
975         .owner             = THIS_MODULE,
976         .release           = inet_release,
977         .bind              = inet_bind,
978         .connect           = inet_dgram_connect,
979         .socketpair        = sock_no_socketpair,
980         .accept            = sock_no_accept,
981         .getname           = inet_getname,
982         .poll              = udp_poll,
983         .ioctl             = inet_ioctl,
984         .listen            = sock_no_listen,
985         .shutdown          = inet_shutdown,
986         .setsockopt        = sock_common_setsockopt,
987         .getsockopt        = sock_common_getsockopt,
988         .sendmsg           = inet_sendmsg,
989         .recvmsg           = inet_recvmsg,
990         .mmap              = sock_no_mmap,
991         .sendpage          = inet_sendpage,
992         .set_peek_off      = sk_set_peek_off,
993 #ifdef CONFIG_COMPAT
994         .compat_setsockopt = compat_sock_common_setsockopt,
995         .compat_getsockopt = compat_sock_common_getsockopt,
996         .compat_ioctl      = inet_compat_ioctl,
997 #endif
998 };
999 EXPORT_SYMBOL(inet_dgram_ops);
1000
1001 /*
1002  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
1003  * udp_poll
1004  */
1005 static const struct proto_ops inet_sockraw_ops = {
1006         .family            = PF_INET,
1007         .owner             = THIS_MODULE,
1008         .release           = inet_release,
1009         .bind              = inet_bind,
1010         .connect           = inet_dgram_connect,
1011         .socketpair        = sock_no_socketpair,
1012         .accept            = sock_no_accept,
1013         .getname           = inet_getname,
1014         .poll              = datagram_poll,
1015         .ioctl             = inet_ioctl,
1016         .listen            = sock_no_listen,
1017         .shutdown          = inet_shutdown,
1018         .setsockopt        = sock_common_setsockopt,
1019         .getsockopt        = sock_common_getsockopt,
1020         .sendmsg           = inet_sendmsg,
1021         .recvmsg           = inet_recvmsg,
1022         .mmap              = sock_no_mmap,
1023         .sendpage          = inet_sendpage,
1024 #ifdef CONFIG_COMPAT
1025         .compat_setsockopt = compat_sock_common_setsockopt,
1026         .compat_getsockopt = compat_sock_common_getsockopt,
1027         .compat_ioctl      = inet_compat_ioctl,
1028 #endif
1029 };
1030
1031 static const struct net_proto_family inet_family_ops = {
1032         .family = PF_INET,
1033         .create = inet_create,
1034         .owner  = THIS_MODULE,
1035 };
1036
1037 /* Upon startup we insert all the elements in inetsw_array[] into
1038  * the linked list inetsw.
1039  */
1040 static struct inet_protosw inetsw_array[] =
1041 {
1042         {
1043                 .type =       SOCK_STREAM,
1044                 .protocol =   IPPROTO_TCP,
1045                 .prot =       &tcp_prot,
1046                 .ops =        &inet_stream_ops,
1047                 .flags =      INET_PROTOSW_PERMANENT |
1048                               INET_PROTOSW_ICSK,
1049         },
1050
1051         {
1052                 .type =       SOCK_DGRAM,
1053                 .protocol =   IPPROTO_UDP,
1054                 .prot =       &udp_prot,
1055                 .ops =        &inet_dgram_ops,
1056                 .flags =      INET_PROTOSW_PERMANENT,
1057        },
1058
1059        {
1060                 .type =       SOCK_DGRAM,
1061                 .protocol =   IPPROTO_ICMP,
1062                 .prot =       &ping_prot,
1063                 .ops =        &inet_sockraw_ops,
1064                 .flags =      INET_PROTOSW_REUSE,
1065        },
1066
1067        {
1068                .type =       SOCK_RAW,
1069                .protocol =   IPPROTO_IP,        /* wild card */
1070                .prot =       &raw_prot,
1071                .ops =        &inet_sockraw_ops,
1072                .flags =      INET_PROTOSW_REUSE,
1073        }
1074 };
1075
1076 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1077
1078 void inet_register_protosw(struct inet_protosw *p)
1079 {
1080         struct list_head *lh;
1081         struct inet_protosw *answer;
1082         int protocol = p->protocol;
1083         struct list_head *last_perm;
1084
1085         spin_lock_bh(&inetsw_lock);
1086
1087         if (p->type >= SOCK_MAX)
1088                 goto out_illegal;
1089
1090         /* If we are trying to override a permanent protocol, bail. */
1091         last_perm = &inetsw[p->type];
1092         list_for_each(lh, &inetsw[p->type]) {
1093                 answer = list_entry(lh, struct inet_protosw, list);
1094                 /* Check only the non-wild match. */
1095                 if ((INET_PROTOSW_PERMANENT & answer->flags) == 0)
1096                         break;
1097                 if (protocol == answer->protocol)
1098                         goto out_permanent;
1099                 last_perm = lh;
1100         }
1101
1102         /* Add the new entry after the last permanent entry if any, so that
1103          * the new entry does not override a permanent entry when matched with
1104          * a wild-card protocol. But it is allowed to override any existing
1105          * non-permanent entry.  This means that when we remove this entry, the
1106          * system automatically returns to the old behavior.
1107          */
1108         list_add_rcu(&p->list, last_perm);
1109 out:
1110         spin_unlock_bh(&inetsw_lock);
1111
1112         return;
1113
1114 out_permanent:
1115         pr_err("Attempt to override permanent protocol %d\n", protocol);
1116         goto out;
1117
1118 out_illegal:
1119         pr_err("Ignoring attempt to register invalid socket type %d\n",
1120                p->type);
1121         goto out;
1122 }
1123 EXPORT_SYMBOL(inet_register_protosw);
1124
1125 void inet_unregister_protosw(struct inet_protosw *p)
1126 {
1127         if (INET_PROTOSW_PERMANENT & p->flags) {
1128                 pr_err("Attempt to unregister permanent protocol %d\n",
1129                        p->protocol);
1130         } else {
1131                 spin_lock_bh(&inetsw_lock);
1132                 list_del_rcu(&p->list);
1133                 spin_unlock_bh(&inetsw_lock);
1134
1135                 synchronize_net();
1136         }
1137 }
1138 EXPORT_SYMBOL(inet_unregister_protosw);
1139
1140 static int inet_sk_reselect_saddr(struct sock *sk)
1141 {
1142         struct inet_sock *inet = inet_sk(sk);
1143         __be32 old_saddr = inet->inet_saddr;
1144         __be32 daddr = inet->inet_daddr;
1145         struct flowi4 *fl4;
1146         struct rtable *rt;
1147         __be32 new_saddr;
1148         struct ip_options_rcu *inet_opt;
1149
1150         inet_opt = rcu_dereference_protected(inet->inet_opt,
1151                                              lockdep_sock_is_held(sk));
1152         if (inet_opt && inet_opt->opt.srr)
1153                 daddr = inet_opt->opt.faddr;
1154
1155         /* Query new route. */
1156         fl4 = &inet->cork.fl.u.ip4;
1157         rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1158                               sk->sk_bound_dev_if, sk->sk_protocol,
1159                               inet->inet_sport, inet->inet_dport, sk);
1160         if (IS_ERR(rt))
1161                 return PTR_ERR(rt);
1162
1163         sk_setup_caps(sk, &rt->dst);
1164
1165         new_saddr = fl4->saddr;
1166
1167         if (new_saddr == old_saddr)
1168                 return 0;
1169
1170         if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) {
1171                 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1172                         __func__, &old_saddr, &new_saddr);
1173         }
1174
1175         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1176
1177         /*
1178          * XXX The only one ugly spot where we need to
1179          * XXX really change the sockets identity after
1180          * XXX it has entered the hashes. -DaveM
1181          *
1182          * Besides that, it does not check for connection
1183          * uniqueness. Wait for troubles.
1184          */
1185         return __sk_prot_rehash(sk);
1186 }
1187
1188 int inet_sk_rebuild_header(struct sock *sk)
1189 {
1190         struct inet_sock *inet = inet_sk(sk);
1191         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1192         __be32 daddr;
1193         struct ip_options_rcu *inet_opt;
1194         struct flowi4 *fl4;
1195         int err;
1196
1197         /* Route is OK, nothing to do. */
1198         if (rt)
1199                 return 0;
1200
1201         /* Reroute. */
1202         rcu_read_lock();
1203         inet_opt = rcu_dereference(inet->inet_opt);
1204         daddr = inet->inet_daddr;
1205         if (inet_opt && inet_opt->opt.srr)
1206                 daddr = inet_opt->opt.faddr;
1207         rcu_read_unlock();
1208         fl4 = &inet->cork.fl.u.ip4;
1209         rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1210                                    inet->inet_dport, inet->inet_sport,
1211                                    sk->sk_protocol, RT_CONN_FLAGS(sk),
1212                                    sk->sk_bound_dev_if);
1213         if (!IS_ERR(rt)) {
1214                 err = 0;
1215                 sk_setup_caps(sk, &rt->dst);
1216         } else {
1217                 err = PTR_ERR(rt);
1218
1219                 /* Routing failed... */
1220                 sk->sk_route_caps = 0;
1221                 /*
1222                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1223                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1224                  */
1225                 if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr ||
1226                     sk->sk_state != TCP_SYN_SENT ||
1227                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1228                     (err = inet_sk_reselect_saddr(sk)) != 0)
1229                         sk->sk_err_soft = -err;
1230         }
1231
1232         return err;
1233 }
1234 EXPORT_SYMBOL(inet_sk_rebuild_header);
1235
1236 void inet_sk_set_state(struct sock *sk, int state)
1237 {
1238         trace_inet_sock_set_state(sk, sk->sk_state, state);
1239         sk->sk_state = state;
1240 }
1241 EXPORT_SYMBOL(inet_sk_set_state);
1242
1243 void inet_sk_state_store(struct sock *sk, int newstate)
1244 {
1245         trace_inet_sock_set_state(sk, sk->sk_state, newstate);
1246         smp_store_release(&sk->sk_state, newstate);
1247 }
1248
1249 struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1250                                  netdev_features_t features)
1251 {
1252         bool udpfrag = false, fixedid = false, gso_partial, encap;
1253         struct sk_buff *segs = ERR_PTR(-EINVAL);
1254         const struct net_offload *ops;
1255         unsigned int offset = 0;
1256         struct iphdr *iph;
1257         int proto, tot_len;
1258         int nhoff;
1259         int ihl;
1260         int id;
1261
1262         skb_reset_network_header(skb);
1263         nhoff = skb_network_header(skb) - skb_mac_header(skb);
1264         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1265                 goto out;
1266
1267         iph = ip_hdr(skb);
1268         ihl = iph->ihl * 4;
1269         if (ihl < sizeof(*iph))
1270                 goto out;
1271
1272         id = ntohs(iph->id);
1273         proto = iph->protocol;
1274
1275         /* Warning: after this point, iph might be no longer valid */
1276         if (unlikely(!pskb_may_pull(skb, ihl)))
1277                 goto out;
1278         __skb_pull(skb, ihl);
1279
1280         encap = SKB_GSO_CB(skb)->encap_level > 0;
1281         if (encap)
1282                 features &= skb->dev->hw_enc_features;
1283         SKB_GSO_CB(skb)->encap_level += ihl;
1284
1285         skb_reset_transport_header(skb);
1286
1287         segs = ERR_PTR(-EPROTONOSUPPORT);
1288
1289         if (!skb->encapsulation || encap) {
1290                 udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
1291                 fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID);
1292
1293                 /* fixed ID is invalid if DF bit is not set */
1294                 if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF)))
1295                         goto out;
1296         }
1297
1298         ops = rcu_dereference(inet_offloads[proto]);
1299         if (likely(ops && ops->callbacks.gso_segment))
1300                 segs = ops->callbacks.gso_segment(skb, features);
1301
1302         if (IS_ERR_OR_NULL(segs))
1303                 goto out;
1304
1305         gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
1306
1307         skb = segs;
1308         do {
1309                 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1310                 if (udpfrag) {
1311                         iph->frag_off = htons(offset >> 3);
1312                         if (skb->next)
1313                                 iph->frag_off |= htons(IP_MF);
1314                         offset += skb->len - nhoff - ihl;
1315                         tot_len = skb->len - nhoff;
1316                 } else if (skb_is_gso(skb)) {
1317                         if (!fixedid) {
1318                                 iph->id = htons(id);
1319                                 id += skb_shinfo(skb)->gso_segs;
1320                         }
1321
1322                         if (gso_partial)
1323                                 tot_len = skb_shinfo(skb)->gso_size +
1324                                           SKB_GSO_CB(skb)->data_offset +
1325                                           skb->head - (unsigned char *)iph;
1326                         else
1327                                 tot_len = skb->len - nhoff;
1328                 } else {
1329                         if (!fixedid)
1330                                 iph->id = htons(id++);
1331                         tot_len = skb->len - nhoff;
1332                 }
1333                 iph->tot_len = htons(tot_len);
1334                 ip_send_check(iph);
1335                 if (encap)
1336                         skb_reset_inner_headers(skb);
1337                 skb->network_header = (u8 *)iph - skb->head;
1338         } while ((skb = skb->next));
1339
1340 out:
1341         return segs;
1342 }
1343 EXPORT_SYMBOL(inet_gso_segment);
1344
1345 struct sk_buff **inet_gro_receive(struct sk_buff **head, struct sk_buff *skb)
1346 {
1347         const struct net_offload *ops;
1348         struct sk_buff **pp = NULL;
1349         struct sk_buff *p;
1350         const struct iphdr *iph;
1351         unsigned int hlen;
1352         unsigned int off;
1353         unsigned int id;
1354         int flush = 1;
1355         int proto;
1356
1357         off = skb_gro_offset(skb);
1358         hlen = off + sizeof(*iph);
1359         iph = skb_gro_header_fast(skb, off);
1360         if (skb_gro_header_hard(skb, hlen)) {
1361                 iph = skb_gro_header_slow(skb, hlen, off);
1362                 if (unlikely(!iph))
1363                         goto out;
1364         }
1365
1366         proto = iph->protocol;
1367
1368         rcu_read_lock();
1369         ops = rcu_dereference(inet_offloads[proto]);
1370         if (!ops || !ops->callbacks.gro_receive)
1371                 goto out_unlock;
1372
1373         if (*(u8 *)iph != 0x45)
1374                 goto out_unlock;
1375
1376         if (ip_is_fragment(iph))
1377                 goto out_unlock;
1378
1379         if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1380                 goto out_unlock;
1381
1382         id = ntohl(*(__be32 *)&iph->id);
1383         flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
1384         id >>= 16;
1385
1386         for (p = *head; p; p = p->next) {
1387                 struct iphdr *iph2;
1388                 u16 flush_id;
1389
1390                 if (!NAPI_GRO_CB(p)->same_flow)
1391                         continue;
1392
1393                 iph2 = (struct iphdr *)(p->data + off);
1394                 /* The above works because, with the exception of the top
1395                  * (inner most) layer, we only aggregate pkts with the same
1396                  * hdr length so all the hdrs we'll need to verify will start
1397                  * at the same offset.
1398                  */
1399                 if ((iph->protocol ^ iph2->protocol) |
1400                     ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1401                     ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1402                         NAPI_GRO_CB(p)->same_flow = 0;
1403                         continue;
1404                 }
1405
1406                 /* All fields must match except length and checksum. */
1407                 NAPI_GRO_CB(p)->flush |=
1408                         (iph->ttl ^ iph2->ttl) |
1409                         (iph->tos ^ iph2->tos) |
1410                         ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF));
1411
1412                 NAPI_GRO_CB(p)->flush |= flush;
1413
1414                 /* We need to store of the IP ID check to be included later
1415                  * when we can verify that this packet does in fact belong
1416                  * to a given flow.
1417                  */
1418                 flush_id = (u16)(id - ntohs(iph2->id));
1419
1420                 /* This bit of code makes it much easier for us to identify
1421                  * the cases where we are doing atomic vs non-atomic IP ID
1422                  * checks.  Specifically an atomic check can return IP ID
1423                  * values 0 - 0xFFFF, while a non-atomic check can only
1424                  * return 0 or 0xFFFF.
1425                  */
1426                 if (!NAPI_GRO_CB(p)->is_atomic ||
1427                     !(iph->frag_off & htons(IP_DF))) {
1428                         flush_id ^= NAPI_GRO_CB(p)->count;
1429                         flush_id = flush_id ? 0xFFFF : 0;
1430                 }
1431
1432                 /* If the previous IP ID value was based on an atomic
1433                  * datagram we can overwrite the value and ignore it.
1434                  */
1435                 if (NAPI_GRO_CB(skb)->is_atomic)
1436                         NAPI_GRO_CB(p)->flush_id = flush_id;
1437                 else
1438                         NAPI_GRO_CB(p)->flush_id |= flush_id;
1439         }
1440
1441         NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF));
1442         NAPI_GRO_CB(skb)->flush |= flush;
1443         skb_set_network_header(skb, off);
1444         /* The above will be needed by the transport layer if there is one
1445          * immediately following this IP hdr.
1446          */
1447
1448         /* Note : No need to call skb_gro_postpull_rcsum() here,
1449          * as we already checked checksum over ipv4 header was 0
1450          */
1451         skb_gro_pull(skb, sizeof(*iph));
1452         skb_set_transport_header(skb, skb_gro_offset(skb));
1453
1454         pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
1455
1456 out_unlock:
1457         rcu_read_unlock();
1458
1459 out:
1460         skb_gro_flush_final(skb, pp, flush);
1461
1462         return pp;
1463 }
1464 EXPORT_SYMBOL(inet_gro_receive);
1465
1466 static struct sk_buff **ipip_gro_receive(struct sk_buff **head,
1467                                          struct sk_buff *skb)
1468 {
1469         if (NAPI_GRO_CB(skb)->encap_mark) {
1470                 NAPI_GRO_CB(skb)->flush = 1;
1471                 return NULL;
1472         }
1473
1474         NAPI_GRO_CB(skb)->encap_mark = 1;
1475
1476         return inet_gro_receive(head, skb);
1477 }
1478
1479 #define SECONDS_PER_DAY 86400
1480
1481 /* inet_current_timestamp - Return IP network timestamp
1482  *
1483  * Return milliseconds since midnight in network byte order.
1484  */
1485 __be32 inet_current_timestamp(void)
1486 {
1487         u32 secs;
1488         u32 msecs;
1489         struct timespec64 ts;
1490
1491         ktime_get_real_ts64(&ts);
1492
1493         /* Get secs since midnight. */
1494         (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs);
1495         /* Convert to msecs. */
1496         msecs = secs * MSEC_PER_SEC;
1497         /* Convert nsec to msec. */
1498         msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;
1499
1500         /* Convert to network byte order. */
1501         return htonl(msecs);
1502 }
1503 EXPORT_SYMBOL(inet_current_timestamp);
1504
1505 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
1506 {
1507         if (sk->sk_family == AF_INET)
1508                 return ip_recv_error(sk, msg, len, addr_len);
1509 #if IS_ENABLED(CONFIG_IPV6)
1510         if (sk->sk_family == AF_INET6)
1511                 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
1512 #endif
1513         return -EINVAL;
1514 }
1515
1516 int inet_gro_complete(struct sk_buff *skb, int nhoff)
1517 {
1518         __be16 newlen = htons(skb->len - nhoff);
1519         struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1520         const struct net_offload *ops;
1521         int proto = iph->protocol;
1522         int err = -ENOSYS;
1523
1524         if (skb->encapsulation) {
1525                 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IP));
1526                 skb_set_inner_network_header(skb, nhoff);
1527         }
1528
1529         csum_replace2(&iph->check, iph->tot_len, newlen);
1530         iph->tot_len = newlen;
1531
1532         rcu_read_lock();
1533         ops = rcu_dereference(inet_offloads[proto]);
1534         if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1535                 goto out_unlock;
1536
1537         /* Only need to add sizeof(*iph) to get to the next hdr below
1538          * because any hdr with option will have been flushed in
1539          * inet_gro_receive().
1540          */
1541         err = ops->callbacks.gro_complete(skb, nhoff + sizeof(*iph));
1542
1543 out_unlock:
1544         rcu_read_unlock();
1545
1546         return err;
1547 }
1548 EXPORT_SYMBOL(inet_gro_complete);
1549
1550 static int ipip_gro_complete(struct sk_buff *skb, int nhoff)
1551 {
1552         skb->encapsulation = 1;
1553         skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
1554         return inet_gro_complete(skb, nhoff);
1555 }
1556
1557 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1558                          unsigned short type, unsigned char protocol,
1559                          struct net *net)
1560 {
1561         struct socket *sock;
1562         int rc = sock_create_kern(net, family, type, protocol, &sock);
1563
1564         if (rc == 0) {
1565                 *sk = sock->sk;
1566                 (*sk)->sk_allocation = GFP_ATOMIC;
1567                 /*
1568                  * Unhash it so that IP input processing does not even see it,
1569                  * we do not wish this socket to see incoming packets.
1570                  */
1571                 (*sk)->sk_prot->unhash(*sk);
1572         }
1573         return rc;
1574 }
1575 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1576
1577 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
1578 {
1579         return  *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt);
1580 }
1581 EXPORT_SYMBOL_GPL(snmp_get_cpu_field);
1582
1583 unsigned long snmp_fold_field(void __percpu *mib, int offt)
1584 {
1585         unsigned long res = 0;
1586         int i;
1587
1588         for_each_possible_cpu(i)
1589                 res += snmp_get_cpu_field(mib, i, offt);
1590         return res;
1591 }
1592 EXPORT_SYMBOL_GPL(snmp_fold_field);
1593
1594 #if BITS_PER_LONG==32
1595
1596 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt,
1597                          size_t syncp_offset)
1598 {
1599         void *bhptr;
1600         struct u64_stats_sync *syncp;
1601         u64 v;
1602         unsigned int start;
1603
1604         bhptr = per_cpu_ptr(mib, cpu);
1605         syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1606         do {
1607                 start = u64_stats_fetch_begin_irq(syncp);
1608                 v = *(((u64 *)bhptr) + offt);
1609         } while (u64_stats_fetch_retry_irq(syncp, start));
1610
1611         return v;
1612 }
1613 EXPORT_SYMBOL_GPL(snmp_get_cpu_field64);
1614
1615 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1616 {
1617         u64 res = 0;
1618         int cpu;
1619
1620         for_each_possible_cpu(cpu) {
1621                 res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset);
1622         }
1623         return res;
1624 }
1625 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1626 #endif
1627
1628 #ifdef CONFIG_IP_MULTICAST
1629 static const struct net_protocol igmp_protocol = {
1630         .handler =      igmp_rcv,
1631         .netns_ok =     1,
1632 };
1633 #endif
1634
1635 /* thinking of making this const? Don't.
1636  * early_demux can change based on sysctl.
1637  */
1638 static struct net_protocol tcp_protocol = {
1639         .early_demux    =       tcp_v4_early_demux,
1640         .early_demux_handler =  tcp_v4_early_demux,
1641         .handler        =       tcp_v4_rcv,
1642         .err_handler    =       tcp_v4_err,
1643         .no_policy      =       1,
1644         .netns_ok       =       1,
1645         .icmp_strict_tag_validation = 1,
1646 };
1647
1648 /* thinking of making this const? Don't.
1649  * early_demux can change based on sysctl.
1650  */
1651 static struct net_protocol udp_protocol = {
1652         .early_demux =  udp_v4_early_demux,
1653         .early_demux_handler =  udp_v4_early_demux,
1654         .handler =      udp_rcv,
1655         .err_handler =  udp_err,
1656         .no_policy =    1,
1657         .netns_ok =     1,
1658 };
1659
1660 static const struct net_protocol icmp_protocol = {
1661         .handler =      icmp_rcv,
1662         .err_handler =  icmp_err,
1663         .no_policy =    1,
1664         .netns_ok =     1,
1665 };
1666
1667 static __net_init int ipv4_mib_init_net(struct net *net)
1668 {
1669         int i;
1670
1671         net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1672         if (!net->mib.tcp_statistics)
1673                 goto err_tcp_mib;
1674         net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1675         if (!net->mib.ip_statistics)
1676                 goto err_ip_mib;
1677
1678         for_each_possible_cpu(i) {
1679                 struct ipstats_mib *af_inet_stats;
1680                 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1681                 u64_stats_init(&af_inet_stats->syncp);
1682         }
1683
1684         net->mib.net_statistics = alloc_percpu(struct linux_mib);
1685         if (!net->mib.net_statistics)
1686                 goto err_net_mib;
1687         net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1688         if (!net->mib.udp_statistics)
1689                 goto err_udp_mib;
1690         net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1691         if (!net->mib.udplite_statistics)
1692                 goto err_udplite_mib;
1693         net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1694         if (!net->mib.icmp_statistics)
1695                 goto err_icmp_mib;
1696         net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1697                                               GFP_KERNEL);
1698         if (!net->mib.icmpmsg_statistics)
1699                 goto err_icmpmsg_mib;
1700
1701         tcp_mib_init(net);
1702         return 0;
1703
1704 err_icmpmsg_mib:
1705         free_percpu(net->mib.icmp_statistics);
1706 err_icmp_mib:
1707         free_percpu(net->mib.udplite_statistics);
1708 err_udplite_mib:
1709         free_percpu(net->mib.udp_statistics);
1710 err_udp_mib:
1711         free_percpu(net->mib.net_statistics);
1712 err_net_mib:
1713         free_percpu(net->mib.ip_statistics);
1714 err_ip_mib:
1715         free_percpu(net->mib.tcp_statistics);
1716 err_tcp_mib:
1717         return -ENOMEM;
1718 }
1719
1720 static __net_exit void ipv4_mib_exit_net(struct net *net)
1721 {
1722         kfree(net->mib.icmpmsg_statistics);
1723         free_percpu(net->mib.icmp_statistics);
1724         free_percpu(net->mib.udplite_statistics);
1725         free_percpu(net->mib.udp_statistics);
1726         free_percpu(net->mib.net_statistics);
1727         free_percpu(net->mib.ip_statistics);
1728         free_percpu(net->mib.tcp_statistics);
1729 }
1730
1731 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1732         .init = ipv4_mib_init_net,
1733         .exit = ipv4_mib_exit_net,
1734 };
1735
1736 static int __init init_ipv4_mibs(void)
1737 {
1738         return register_pernet_subsys(&ipv4_mib_ops);
1739 }
1740
1741 static __net_init int inet_init_net(struct net *net)
1742 {
1743         /*
1744          * Set defaults for local port range
1745          */
1746         seqlock_init(&net->ipv4.ip_local_ports.lock);
1747         net->ipv4.ip_local_ports.range[0] =  32768;
1748         net->ipv4.ip_local_ports.range[1] =  60999;
1749
1750         seqlock_init(&net->ipv4.ping_group_range.lock);
1751         /*
1752          * Sane defaults - nobody may create ping sockets.
1753          * Boot scripts should set this to distro-specific group.
1754          */
1755         net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1);
1756         net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0);
1757
1758         /* Default values for sysctl-controlled parameters.
1759          * We set them here, in case sysctl is not compiled.
1760          */
1761         net->ipv4.sysctl_ip_default_ttl = IPDEFTTL;
1762         net->ipv4.sysctl_ip_dynaddr = 0;
1763         net->ipv4.sysctl_ip_early_demux = 1;
1764         net->ipv4.sysctl_udp_early_demux = 1;
1765         net->ipv4.sysctl_tcp_early_demux = 1;
1766 #ifdef CONFIG_SYSCTL
1767         net->ipv4.sysctl_ip_prot_sock = PROT_SOCK;
1768 #endif
1769
1770         /* Some igmp sysctl, whose values are always used */
1771         net->ipv4.sysctl_igmp_max_memberships = 20;
1772         net->ipv4.sysctl_igmp_max_msf = 10;
1773         /* IGMP reports for link-local multicast groups are enabled by default */
1774         net->ipv4.sysctl_igmp_llm_reports = 1;
1775         net->ipv4.sysctl_igmp_qrv = 2;
1776
1777         return 0;
1778 }
1779
1780 static __net_exit void inet_exit_net(struct net *net)
1781 {
1782 }
1783
1784 static __net_initdata struct pernet_operations af_inet_ops = {
1785         .init = inet_init_net,
1786         .exit = inet_exit_net,
1787 };
1788
1789 static int __init init_inet_pernet_ops(void)
1790 {
1791         return register_pernet_subsys(&af_inet_ops);
1792 }
1793
1794 static int ipv4_proc_init(void);
1795
1796 /*
1797  *      IP protocol layer initialiser
1798  */
1799
1800 static struct packet_offload ip_packet_offload __read_mostly = {
1801         .type = cpu_to_be16(ETH_P_IP),
1802         .callbacks = {
1803                 .gso_segment = inet_gso_segment,
1804                 .gro_receive = inet_gro_receive,
1805                 .gro_complete = inet_gro_complete,
1806         },
1807 };
1808
1809 static const struct net_offload ipip_offload = {
1810         .callbacks = {
1811                 .gso_segment    = inet_gso_segment,
1812                 .gro_receive    = ipip_gro_receive,
1813                 .gro_complete   = ipip_gro_complete,
1814         },
1815 };
1816
1817 static int __init ipip_offload_init(void)
1818 {
1819         return inet_add_offload(&ipip_offload, IPPROTO_IPIP);
1820 }
1821
1822 static int __init ipv4_offload_init(void)
1823 {
1824         /*
1825          * Add offloads
1826          */
1827         if (udpv4_offload_init() < 0)
1828                 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1829         if (tcpv4_offload_init() < 0)
1830                 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1831         if (ipip_offload_init() < 0)
1832                 pr_crit("%s: Cannot add IPIP protocol offload\n", __func__);
1833
1834         dev_add_offload(&ip_packet_offload);
1835         return 0;
1836 }
1837
1838 fs_initcall(ipv4_offload_init);
1839
1840 static struct packet_type ip_packet_type __read_mostly = {
1841         .type = cpu_to_be16(ETH_P_IP),
1842         .func = ip_rcv,
1843 };
1844
1845 static int __init inet_init(void)
1846 {
1847         struct inet_protosw *q;
1848         struct list_head *r;
1849         int rc = -EINVAL;
1850
1851         sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
1852
1853         rc = proto_register(&tcp_prot, 1);
1854         if (rc)
1855                 goto out;
1856
1857         rc = proto_register(&udp_prot, 1);
1858         if (rc)
1859                 goto out_unregister_tcp_proto;
1860
1861         rc = proto_register(&raw_prot, 1);
1862         if (rc)
1863                 goto out_unregister_udp_proto;
1864
1865         rc = proto_register(&ping_prot, 1);
1866         if (rc)
1867                 goto out_unregister_raw_proto;
1868
1869         /*
1870          *      Tell SOCKET that we are alive...
1871          */
1872
1873         (void)sock_register(&inet_family_ops);
1874
1875 #ifdef CONFIG_SYSCTL
1876         ip_static_sysctl_init();
1877 #endif
1878
1879         /*
1880          *      Add all the base protocols.
1881          */
1882
1883         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1884                 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1885         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1886                 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1887         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1888                 pr_crit("%s: Cannot add TCP protocol\n", __func__);
1889 #ifdef CONFIG_IP_MULTICAST
1890         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1891                 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1892 #endif
1893
1894         /* Register the socket-side information for inet_create. */
1895         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1896                 INIT_LIST_HEAD(r);
1897
1898         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1899                 inet_register_protosw(q);
1900
1901         /*
1902          *      Set the ARP module up
1903          */
1904
1905         arp_init();
1906
1907         /*
1908          *      Set the IP module up
1909          */
1910
1911         ip_init();
1912
1913         /* Setup TCP slab cache for open requests. */
1914         tcp_init();
1915
1916         /* Setup UDP memory threshold */
1917         udp_init();
1918
1919         /* Add UDP-Lite (RFC 3828) */
1920         udplite4_register();
1921
1922         ping_init();
1923
1924         /*
1925          *      Set the ICMP layer up
1926          */
1927
1928         if (icmp_init() < 0)
1929                 panic("Failed to create the ICMP control socket.\n");
1930
1931         /*
1932          *      Initialise the multicast router
1933          */
1934 #if defined(CONFIG_IP_MROUTE)
1935         if (ip_mr_init())
1936                 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
1937 #endif
1938
1939         if (init_inet_pernet_ops())
1940                 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
1941         /*
1942          *      Initialise per-cpu ipv4 mibs
1943          */
1944
1945         if (init_ipv4_mibs())
1946                 pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
1947
1948         ipv4_proc_init();
1949
1950         ipfrag_init();
1951
1952         dev_add_pack(&ip_packet_type);
1953
1954         ip_tunnel_core_init();
1955
1956         rc = 0;
1957 out:
1958         return rc;
1959 out_unregister_raw_proto:
1960         proto_unregister(&raw_prot);
1961 out_unregister_udp_proto:
1962         proto_unregister(&udp_prot);
1963 out_unregister_tcp_proto:
1964         proto_unregister(&tcp_prot);
1965         goto out;
1966 }
1967
1968 fs_initcall(inet_init);
1969
1970 /* ------------------------------------------------------------------------ */
1971
1972 #ifdef CONFIG_PROC_FS
1973 static int __init ipv4_proc_init(void)
1974 {
1975         int rc = 0;
1976
1977         if (raw_proc_init())
1978                 goto out_raw;
1979         if (tcp4_proc_init())
1980                 goto out_tcp;
1981         if (udp4_proc_init())
1982                 goto out_udp;
1983         if (ping_proc_init())
1984                 goto out_ping;
1985         if (ip_misc_proc_init())
1986                 goto out_misc;
1987 out:
1988         return rc;
1989 out_misc:
1990         ping_proc_exit();
1991 out_ping:
1992         udp4_proc_exit();
1993 out_udp:
1994         tcp4_proc_exit();
1995 out_tcp:
1996         raw_proc_exit();
1997 out_raw:
1998         rc = -ENOMEM;
1999         goto out;
2000 }
2001
2002 #else /* CONFIG_PROC_FS */
2003 static int __init ipv4_proc_init(void)
2004 {
2005         return 0;
2006 }
2007 #endif /* CONFIG_PROC_FS */