1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * PF_INET protocol family socket handler.
8 *
9 * Authors: Ross Biro
10 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Florian La Roche, <flla@stud.uni-sb.de>
12 * Alan Cox, <A.Cox@swansea.ac.uk>
13 *
14 * Changes (see also sock.c)
15 *
16 * piggy,
17 * Karl Knutson : Socket protocol table
18 * A.N.Kuznetsov : Socket death error in accept().
19 * John Richardson : Fix non blocking error in connect()
20 * so sockets that fail to connect
21 * don't return -EINPROGRESS.
22 * Alan Cox : Asynchronous I/O support
23 * Alan Cox : Keep correct socket pointer on sock
24 * structures
25 * when accept() ed
26 * Alan Cox : Semantics of SO_LINGER aren't state
27 * moved to close when you look carefully.
28 * With this fixed and the accept bug fixed
29 * some RPC stuff seems happier.
30 * Niibe Yutaka : 4.4BSD style write async I/O
31 * Alan Cox,
32 * Tony Gale : Fixed reuse semantics.
33 * Alan Cox : bind() shouldn't abort existing but dead
34 * sockets. Stops FTP netin:.. I hope.
35 * Alan Cox : bind() works correctly for RAW sockets.
36 * Note that FreeBSD at least was broken
37 * in this respect so be careful with
38 * compatibility tests...
39 * Alan Cox : routing cache support
40 * Alan Cox : memzero the socket structure for
41 * compactness.
42 * Matt Day : nonblock connect error handler
43 * Alan Cox : Allow large numbers of pending sockets
44 * (eg for big web sites), but only if
45 * specifically application requested.
46 * Alan Cox : New buffering throughout IP. Used
47 * dumbly.
48 * Alan Cox : New buffering now used smartly.
49 * Alan Cox : BSD rather than common sense
50 * interpretation of listen.
51 * Germano Caronni : Assorted small races.
52 * Alan Cox : sendmsg/recvmsg basic support.
53 * Alan Cox : Only sendmsg/recvmsg now supported.
54 * Alan Cox : Locked down bind (see security list).
55 * Alan Cox : Loosened bind a little.
56 * Mike McLagan : ADD/DEL DLCI Ioctls
57 * Willy Konynenberg : Transparent proxying support.
58 * David S. Miller : New socket lookup architecture.
59 * Some other random speedups.
60 * Cyrus Durgin : Cleaned up file for kmod hacks.
61 * Andi Kleen : Fix inet_stream_connect TCP race.
62 */
63
64#define pr_fmt(fmt) "IPv4: " fmt
65
66#include <linux/err.h>
67#include <linux/errno.h>
68#include <linux/types.h>
69#include <linux/socket.h>
70#include <linux/in.h>
71#include <linux/kernel.h>
72#include <linux/kmod.h>
73#include <linux/sched.h>
74#include <linux/timer.h>
75#include <linux/string.h>
76#include <linux/sockios.h>
77#include <linux/net.h>
78#include <linux/capability.h>
79#include <linux/fcntl.h>
80#include <linux/mm.h>
81#include <linux/interrupt.h>
82#include <linux/stat.h>
83#include <linux/init.h>
84#include <linux/poll.h>
85#include <linux/netfilter_ipv4.h>
86#include <linux/random.h>
87#include <linux/slab.h>
88
89#include <linux/uaccess.h>
90
91#include <linux/inet.h>
92#include <linux/igmp.h>
93#include <linux/inetdevice.h>
94#include <linux/netdevice.h>
95#include <net/checksum.h>
96#include <net/ip.h>
97#include <net/protocol.h>
98#include <net/arp.h>
99#include <net/route.h>
100#include <net/ip_fib.h>
101#include <net/inet_connection_sock.h>
102#include <net/gro.h>
103#include <net/gso.h>
104#include <net/tcp.h>
105#include <net/udp.h>
106#include <net/udplite.h>
107#include <net/ping.h>
108#include <linux/skbuff.h>
109#include <net/sock.h>
110#include <net/raw.h>
111#include <net/icmp.h>
112#include <net/inet_common.h>
113#include <net/ip_tunnels.h>
114#include <net/xfrm.h>
115#include <net/net_namespace.h>
116#include <net/secure_seq.h>
117#ifdef CONFIG_IP_MROUTE
118#include <linux/mroute.h>
119#endif
120#include <net/l3mdev.h>
121#include <net/compat.h>
122#include <net/rps.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 */
129static struct list_head inetsw[SOCK_MAX];
130static DEFINE_SPINLOCK(inetsw_lock);
131
132/* New destruction routine */
133
134void inet_sock_destruct(struct sock *sk)
135{
136 struct inet_sock *inet = inet_sk(sk);
137
138 __skb_queue_purge(list: &sk->sk_receive_queue);
139 __skb_queue_purge(list: &sk->sk_error_queue);
140
141 sk_mem_reclaim_final(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, flag: SOCK_DEAD)) {
149 pr_err("Attempt to release alive inet socket %p\n", sk);
150 return;
151 }
152
153 WARN_ON_ONCE(atomic_read(&sk->sk_rmem_alloc));
154 WARN_ON_ONCE(refcount_read(&sk->sk_wmem_alloc));
155 WARN_ON_ONCE(sk->sk_wmem_queued);
156 WARN_ON_ONCE(sk_forward_alloc_get(sk));
157
158 kfree(rcu_dereference_protected(inet->inet_opt, 1));
159 dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
160 dst_release(rcu_dereference_protected(sk->sk_rx_dst, 1));
161}
162EXPORT_SYMBOL(inet_sock_destruct);
163
164/*
165 * The routines beyond this point handle the behaviour of an AF_INET
166 * socket object. Mostly it punts to the subprotocols of IP to do
167 * the work.
168 */
169
170/*
171 * Automatically bind an unbound socket.
172 */
173
174static int inet_autobind(struct sock *sk)
175{
176 struct inet_sock *inet;
177 /* We may need to bind the socket. */
178 lock_sock(sk);
179 inet = inet_sk(sk);
180 if (!inet->inet_num) {
181 if (sk->sk_prot->get_port(sk, 0)) {
182 release_sock(sk);
183 return -EAGAIN;
184 }
185 inet->inet_sport = htons(inet->inet_num);
186 }
187 release_sock(sk);
188 return 0;
189}
190
191int __inet_listen_sk(struct sock *sk, int backlog)
192{
193 unsigned char old_state = sk->sk_state;
194 int err, tcp_fastopen;
195
196 if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
197 return -EINVAL;
198
199 WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
200 /* Really, if the socket is already in listen state
201 * we can only allow the backlog to be adjusted.
202 */
203 if (old_state != TCP_LISTEN) {
204 /* Enable TFO w/o requiring TCP_FASTOPEN socket option.
205 * Note that only TCP sockets (SOCK_STREAM) will reach here.
206 * Also fastopen backlog may already been set via the option
207 * because the socket was in TCP_LISTEN state previously but
208 * was shutdown() rather than close().
209 */
210 tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen);
211 if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) &&
212 (tcp_fastopen & TFO_SERVER_ENABLE) &&
213 !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) {
214 fastopen_queue_tune(sk, backlog);
215 tcp_fastopen_init_key_once(net: sock_net(sk));
216 }
217
218 err = inet_csk_listen_start(sk);
219 if (err)
220 return err;
221
222 tcp_call_bpf(sk, op: BPF_SOCK_OPS_TCP_LISTEN_CB, nargs: 0, NULL);
223 }
224 return 0;
225}
226
227/*
228 * Move a socket into listening state.
229 */
230int inet_listen(struct socket *sock, int backlog)
231{
232 struct sock *sk = sock->sk;
233 int err = -EINVAL;
234
235 lock_sock(sk);
236
237 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
238 goto out;
239
240 err = __inet_listen_sk(sk, backlog);
241
242out:
243 release_sock(sk);
244 return err;
245}
246EXPORT_SYMBOL(inet_listen);
247
248/*
249 * Create an inet socket.
250 */
251
252static int inet_create(struct net *net, struct socket *sock, int protocol,
253 int kern)
254{
255 struct sock *sk;
256 struct inet_protosw *answer;
257 struct inet_sock *inet;
258 struct proto *answer_prot;
259 unsigned char answer_flags;
260 int try_loading_module = 0;
261 int err;
262
263 if (protocol < 0 || protocol >= IPPROTO_MAX)
264 return -EINVAL;
265
266 sock->state = SS_UNCONNECTED;
267
268 /* Look for the requested type/protocol pair. */
269lookup_protocol:
270 err = -ESOCKTNOSUPPORT;
271 rcu_read_lock();
272 list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
273
274 err = 0;
275 /* Check the non-wild match. */
276 if (protocol == answer->protocol) {
277 if (protocol != IPPROTO_IP)
278 break;
279 } else {
280 /* Check for the two wild cases. */
281 if (IPPROTO_IP == protocol) {
282 protocol = answer->protocol;
283 break;
284 }
285 if (IPPROTO_IP == answer->protocol)
286 break;
287 }
288 err = -EPROTONOSUPPORT;
289 }
290
291 if (unlikely(err)) {
292 if (try_loading_module < 2) {
293 rcu_read_unlock();
294 /*
295 * Be more specific, e.g. net-pf-2-proto-132-type-1
296 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
297 */
298 if (++try_loading_module == 1)
299 request_module("net-pf-%d-proto-%d-type-%d",
300 PF_INET, protocol, sock->type);
301 /*
302 * Fall back to generic, e.g. net-pf-2-proto-132
303 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
304 */
305 else
306 request_module("net-pf-%d-proto-%d",
307 PF_INET, protocol);
308 goto lookup_protocol;
309 } else
310 goto out_rcu_unlock;
311 }
312
313 err = -EPERM;
314 if (sock->type == SOCK_RAW && !kern &&
315 !ns_capable(ns: net->user_ns, CAP_NET_RAW))
316 goto out_rcu_unlock;
317
318 sock->ops = answer->ops;
319 answer_prot = answer->prot;
320 answer_flags = answer->flags;
321 rcu_read_unlock();
322
323 WARN_ON(!answer_prot->slab);
324
325 err = -ENOMEM;
326 sk = sk_alloc(net, PF_INET, GFP_KERNEL, prot: answer_prot, kern);
327 if (!sk)
328 goto out;
329
330 err = 0;
331 if (INET_PROTOSW_REUSE & answer_flags)
332 sk->sk_reuse = SK_CAN_REUSE;
333
334 if (INET_PROTOSW_ICSK & answer_flags)
335 inet_init_csk_locks(sk);
336
337 inet = inet_sk(sk);
338 inet_assign_bit(IS_ICSK, sk, INET_PROTOSW_ICSK & answer_flags);
339
340 inet_clear_bit(NODEFRAG, sk);
341
342 if (SOCK_RAW == sock->type) {
343 inet->inet_num = protocol;
344 if (IPPROTO_RAW == protocol)
345 inet_set_bit(HDRINCL, sk);
346 }
347
348 if (READ_ONCE(net->ipv4.sysctl_ip_no_pmtu_disc))
349 inet->pmtudisc = IP_PMTUDISC_DONT;
350 else
351 inet->pmtudisc = IP_PMTUDISC_WANT;
352
353 atomic_set(v: &inet->inet_id, i: 0);
354
355 sock_init_data(sock, sk);
356
357 sk->sk_destruct = inet_sock_destruct;
358 sk->sk_protocol = protocol;
359 sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
360 sk->sk_txrehash = READ_ONCE(net->core.sysctl_txrehash);
361
362 inet->uc_ttl = -1;
363 inet_set_bit(MC_LOOP, sk);
364 inet->mc_ttl = 1;
365 inet_set_bit(MC_ALL, sk);
366 inet->mc_index = 0;
367 inet->mc_list = NULL;
368 inet->rcv_tos = 0;
369
370 if (inet->inet_num) {
371 /* It assumes that any protocol which allows
372 * the user to assign a number at socket
373 * creation time automatically
374 * shares.
375 */
376 inet->inet_sport = htons(inet->inet_num);
377 /* Add to protocol hash chains. */
378 err = sk->sk_prot->hash(sk);
379 if (err) {
380 sk_common_release(sk);
381 goto out;
382 }
383 }
384
385 if (sk->sk_prot->init) {
386 err = sk->sk_prot->init(sk);
387 if (err) {
388 sk_common_release(sk);
389 goto out;
390 }
391 }
392
393 if (!kern) {
394 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
395 if (err) {
396 sk_common_release(sk);
397 goto out;
398 }
399 }
400out:
401 return err;
402out_rcu_unlock:
403 rcu_read_unlock();
404 goto out;
405}
406
407
408/*
409 * The peer socket should always be NULL (or else). When we call this
410 * function we are destroying the object and from then on nobody
411 * should refer to it.
412 */
413int inet_release(struct socket *sock)
414{
415 struct sock *sk = sock->sk;
416
417 if (sk) {
418 long timeout;
419
420 if (!sk->sk_kern_sock)
421 BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk);
422
423 /* Applications forget to leave groups before exiting */
424 ip_mc_drop_socket(sk);
425
426 /* If linger is set, we don't return until the close
427 * is complete. Otherwise we return immediately. The
428 * actually closing is done the same either way.
429 *
430 * If the close is due to the process exiting, we never
431 * linger..
432 */
433 timeout = 0;
434 if (sock_flag(sk, flag: SOCK_LINGER) &&
435 !(current->flags & PF_EXITING))
436 timeout = sk->sk_lingertime;
437 sk->sk_prot->close(sk, timeout);
438 sock->sk = NULL;
439 }
440 return 0;
441}
442EXPORT_SYMBOL(inet_release);
443
444int inet_bind_sk(struct sock *sk, struct sockaddr *uaddr, int addr_len)
445{
446 u32 flags = BIND_WITH_LOCK;
447 int err;
448
449 /* If the socket has its own bind function then use it. (RAW) */
450 if (sk->sk_prot->bind) {
451 return sk->sk_prot->bind(sk, uaddr, addr_len);
452 }
453 if (addr_len < sizeof(struct sockaddr_in))
454 return -EINVAL;
455
456 /* BPF prog is run before any checks are done so that if the prog
457 * changes context in a wrong way it will be caught.
458 */
459 err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr, &addr_len,
460 CGROUP_INET4_BIND, &flags);
461 if (err)
462 return err;
463
464 return __inet_bind(sk, uaddr, addr_len, flags);
465}
466
467int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
468{
469 return inet_bind_sk(sk: sock->sk, uaddr, addr_len);
470}
471EXPORT_SYMBOL(inet_bind);
472
473int __inet_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
474 u32 flags)
475{
476 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
477 struct inet_sock *inet = inet_sk(sk);
478 struct net *net = sock_net(sk);
479 unsigned short snum;
480 int chk_addr_ret;
481 u32 tb_id = RT_TABLE_LOCAL;
482 int err;
483
484 if (addr->sin_family != AF_INET) {
485 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
486 * only if s_addr is INADDR_ANY.
487 */
488 err = -EAFNOSUPPORT;
489 if (addr->sin_family != AF_UNSPEC ||
490 addr->sin_addr.s_addr != htonl(INADDR_ANY))
491 goto out;
492 }
493
494 tb_id = l3mdev_fib_table_by_index(net, ifindex: sk->sk_bound_dev_if) ? : tb_id;
495 chk_addr_ret = inet_addr_type_table(net, addr: addr->sin_addr.s_addr, tb_id);
496
497 /* Not specified by any standard per-se, however it breaks too
498 * many applications when removed. It is unfortunate since
499 * allowing applications to make a non-local bind solves
500 * several problems with systems using dynamic addressing.
501 * (ie. your servers still start up even if your ISDN link
502 * is temporarily down)
503 */
504 err = -EADDRNOTAVAIL;
505 if (!inet_addr_valid_or_nonlocal(net, inet, addr: addr->sin_addr.s_addr,
506 addr_type: chk_addr_ret))
507 goto out;
508
509 snum = ntohs(addr->sin_port);
510 err = -EACCES;
511 if (!(flags & BIND_NO_CAP_NET_BIND_SERVICE) &&
512 snum && inet_port_requires_bind_service(net, port: snum) &&
513 !ns_capable(ns: net->user_ns, CAP_NET_BIND_SERVICE))
514 goto out;
515
516 /* We keep a pair of addresses. rcv_saddr is the one
517 * used by hash lookups, and saddr is used for transmit.
518 *
519 * In the BSD API these are the same except where it
520 * would be illegal to use them (multicast/broadcast) in
521 * which case the sending device address is used.
522 */
523 if (flags & BIND_WITH_LOCK)
524 lock_sock(sk);
525
526 /* Check these errors (active socket, double bind). */
527 err = -EINVAL;
528 if (sk->sk_state != TCP_CLOSE || inet->inet_num)
529 goto out_release_sock;
530
531 inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
532 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
533 inet->inet_saddr = 0; /* Use device */
534
535 /* Make sure we are allowed to bind here. */
536 if (snum || !(inet_test_bit(BIND_ADDRESS_NO_PORT, sk) ||
537 (flags & BIND_FORCE_ADDRESS_NO_PORT))) {
538 err = sk->sk_prot->get_port(sk, snum);
539 if (err) {
540 inet->inet_saddr = inet->inet_rcv_saddr = 0;
541 goto out_release_sock;
542 }
543 if (!(flags & BIND_FROM_BPF)) {
544 err = BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk);
545 if (err) {
546 inet->inet_saddr = inet->inet_rcv_saddr = 0;
547 if (sk->sk_prot->put_port)
548 sk->sk_prot->put_port(sk);
549 goto out_release_sock;
550 }
551 }
552 }
553
554 if (inet->inet_rcv_saddr)
555 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
556 if (snum)
557 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
558 inet->inet_sport = htons(inet->inet_num);
559 inet->inet_daddr = 0;
560 inet->inet_dport = 0;
561 sk_dst_reset(sk);
562 err = 0;
563out_release_sock:
564 if (flags & BIND_WITH_LOCK)
565 release_sock(sk);
566out:
567 return err;
568}
569
570int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
571 int addr_len, int flags)
572{
573 struct sock *sk = sock->sk;
574 const struct proto *prot;
575 int err;
576
577 if (addr_len < sizeof(uaddr->sa_family))
578 return -EINVAL;
579
580 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
581 prot = READ_ONCE(sk->sk_prot);
582
583 if (uaddr->sa_family == AF_UNSPEC)
584 return prot->disconnect(sk, flags);
585
586 if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
587 err = prot->pre_connect(sk, uaddr, addr_len);
588 if (err)
589 return err;
590 }
591
592 if (data_race(!inet_sk(sk)->inet_num) && inet_autobind(sk))
593 return -EAGAIN;
594 return prot->connect(sk, uaddr, addr_len);
595}
596EXPORT_SYMBOL(inet_dgram_connect);
597
598static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
599{
600 DEFINE_WAIT_FUNC(wait, woken_wake_function);
601
602 add_wait_queue(wq_head: sk_sleep(sk), wq_entry: &wait);
603 sk->sk_write_pending += writebias;
604
605 /* Basic assumption: if someone sets sk->sk_err, he _must_
606 * change state of the socket from TCP_SYN_*.
607 * Connect() does not allow to get error notifications
608 * without closing the socket.
609 */
610 while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
611 release_sock(sk);
612 timeo = wait_woken(wq_entry: &wait, TASK_INTERRUPTIBLE, timeout: timeo);
613 lock_sock(sk);
614 if (signal_pending(current) || !timeo)
615 break;
616 }
617 remove_wait_queue(wq_head: sk_sleep(sk), wq_entry: &wait);
618 sk->sk_write_pending -= writebias;
619 return timeo;
620}
621
622/*
623 * Connect to a remote host. There is regrettably still a little
624 * TCP 'magic' in here.
625 */
626int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
627 int addr_len, int flags, int is_sendmsg)
628{
629 struct sock *sk = sock->sk;
630 int err;
631 long timeo;
632
633 /*
634 * uaddr can be NULL and addr_len can be 0 if:
635 * sk is a TCP fastopen active socket and
636 * TCP_FASTOPEN_CONNECT sockopt is set and
637 * we already have a valid cookie for this socket.
638 * In this case, user can call write() after connect().
639 * write() will invoke tcp_sendmsg_fastopen() which calls
640 * __inet_stream_connect().
641 */
642 if (uaddr) {
643 if (addr_len < sizeof(uaddr->sa_family))
644 return -EINVAL;
645
646 if (uaddr->sa_family == AF_UNSPEC) {
647 sk->sk_disconnects++;
648 err = sk->sk_prot->disconnect(sk, flags);
649 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
650 goto out;
651 }
652 }
653
654 switch (sock->state) {
655 default:
656 err = -EINVAL;
657 goto out;
658 case SS_CONNECTED:
659 err = -EISCONN;
660 goto out;
661 case SS_CONNECTING:
662 if (inet_test_bit(DEFER_CONNECT, sk))
663 err = is_sendmsg ? -EINPROGRESS : -EISCONN;
664 else
665 err = -EALREADY;
666 /* Fall out of switch with err, set for this state */
667 break;
668 case SS_UNCONNECTED:
669 err = -EISCONN;
670 if (sk->sk_state != TCP_CLOSE)
671 goto out;
672
673 if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
674 err = sk->sk_prot->pre_connect(sk, uaddr, addr_len);
675 if (err)
676 goto out;
677 }
678
679 err = sk->sk_prot->connect(sk, uaddr, addr_len);
680 if (err < 0)
681 goto out;
682
683 sock->state = SS_CONNECTING;
684
685 if (!err && inet_test_bit(DEFER_CONNECT, sk))
686 goto out;
687
688 /* Just entered SS_CONNECTING state; the only
689 * difference is that return value in non-blocking
690 * case is EINPROGRESS, rather than EALREADY.
691 */
692 err = -EINPROGRESS;
693 break;
694 }
695
696 timeo = sock_sndtimeo(sk, noblock: flags & O_NONBLOCK);
697
698 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
699 int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
700 tcp_sk(sk)->fastopen_req &&
701 tcp_sk(sk)->fastopen_req->data ? 1 : 0;
702 int dis = sk->sk_disconnects;
703
704 /* Error code is set above */
705 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
706 goto out;
707
708 err = sock_intr_errno(timeo);
709 if (signal_pending(current))
710 goto out;
711
712 if (dis != sk->sk_disconnects) {
713 err = -EPIPE;
714 goto out;
715 }
716 }
717
718 /* Connection was closed by RST, timeout, ICMP error
719 * or another process disconnected us.
720 */
721 if (sk->sk_state == TCP_CLOSE)
722 goto sock_error;
723
724 /* sk->sk_err may be not zero now, if RECVERR was ordered by user
725 * and error was received after socket entered established state.
726 * Hence, it is handled normally after connect() return successfully.
727 */
728
729 sock->state = SS_CONNECTED;
730 err = 0;
731out:
732 return err;
733
734sock_error:
735 err = sock_error(sk) ? : -ECONNABORTED;
736 sock->state = SS_UNCONNECTED;
737 sk->sk_disconnects++;
738 if (sk->sk_prot->disconnect(sk, flags))
739 sock->state = SS_DISCONNECTING;
740 goto out;
741}
742EXPORT_SYMBOL(__inet_stream_connect);
743
744int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
745 int addr_len, int flags)
746{
747 int err;
748
749 lock_sock(sk: sock->sk);
750 err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0);
751 release_sock(sk: sock->sk);
752 return err;
753}
754EXPORT_SYMBOL(inet_stream_connect);
755
756void __inet_accept(struct socket *sock, struct socket *newsock, struct sock *newsk)
757{
758 sock_rps_record_flow(sk: newsk);
759 WARN_ON(!((1 << newsk->sk_state) &
760 (TCPF_ESTABLISHED | TCPF_SYN_RECV |
761 TCPF_CLOSE_WAIT | TCPF_CLOSE)));
762
763 if (test_bit(SOCK_SUPPORT_ZC, &sock->flags))
764 set_bit(SOCK_SUPPORT_ZC, addr: &newsock->flags);
765 sock_graft(sk: newsk, parent: newsock);
766
767 newsock->state = SS_CONNECTED;
768}
769
770/*
771 * Accept a pending connection. The TCP layer now gives BSD semantics.
772 */
773
774int inet_accept(struct socket *sock, struct socket *newsock, int flags,
775 bool kern)
776{
777 struct sock *sk1 = sock->sk, *sk2;
778 int err = -EINVAL;
779
780 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
781 sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern);
782 if (!sk2)
783 return err;
784
785 lock_sock(sk: sk2);
786 __inet_accept(sock, newsock, newsk: sk2);
787 release_sock(sk: sk2);
788 return 0;
789}
790EXPORT_SYMBOL(inet_accept);
791
792/*
793 * This does both peername and sockname.
794 */
795int inet_getname(struct socket *sock, struct sockaddr *uaddr,
796 int peer)
797{
798 struct sock *sk = sock->sk;
799 struct inet_sock *inet = inet_sk(sk);
800 DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
801 int sin_addr_len = sizeof(*sin);
802
803 sin->sin_family = AF_INET;
804 lock_sock(sk);
805 if (peer) {
806 if (!inet->inet_dport ||
807 (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
808 peer == 1)) {
809 release_sock(sk);
810 return -ENOTCONN;
811 }
812 sin->sin_port = inet->inet_dport;
813 sin->sin_addr.s_addr = inet->inet_daddr;
814 BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin, &sin_addr_len,
815 CGROUP_INET4_GETPEERNAME);
816 } else {
817 __be32 addr = inet->inet_rcv_saddr;
818 if (!addr)
819 addr = inet->inet_saddr;
820 sin->sin_port = inet->inet_sport;
821 sin->sin_addr.s_addr = addr;
822 BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin, &sin_addr_len,
823 CGROUP_INET4_GETSOCKNAME);
824 }
825 release_sock(sk);
826 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
827 return sin_addr_len;
828}
829EXPORT_SYMBOL(inet_getname);
830
831int inet_send_prepare(struct sock *sk)
832{
833 sock_rps_record_flow(sk);
834
835 /* We may need to bind the socket. */
836 if (data_race(!inet_sk(sk)->inet_num) && !sk->sk_prot->no_autobind &&
837 inet_autobind(sk))
838 return -EAGAIN;
839
840 return 0;
841}
842EXPORT_SYMBOL_GPL(inet_send_prepare);
843
844int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
845{
846 struct sock *sk = sock->sk;
847
848 if (unlikely(inet_send_prepare(sk)))
849 return -EAGAIN;
850
851 return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udp_sendmsg,
852 sk, msg, size);
853}
854EXPORT_SYMBOL(inet_sendmsg);
855
856void inet_splice_eof(struct socket *sock)
857{
858 const struct proto *prot;
859 struct sock *sk = sock->sk;
860
861 if (unlikely(inet_send_prepare(sk)))
862 return;
863
864 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
865 prot = READ_ONCE(sk->sk_prot);
866 if (prot->splice_eof)
867 prot->splice_eof(sock);
868}
869EXPORT_SYMBOL_GPL(inet_splice_eof);
870
871INDIRECT_CALLABLE_DECLARE(int udp_recvmsg(struct sock *, struct msghdr *,
872 size_t, int, int *));
873int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
874 int flags)
875{
876 struct sock *sk = sock->sk;
877 int addr_len = 0;
878 int err;
879
880 if (likely(!(flags & MSG_ERRQUEUE)))
881 sock_rps_record_flow(sk);
882
883 err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
884 sk, msg, size, flags, &addr_len);
885 if (err >= 0)
886 msg->msg_namelen = addr_len;
887 return err;
888}
889EXPORT_SYMBOL(inet_recvmsg);
890
891int inet_shutdown(struct socket *sock, int how)
892{
893 struct sock *sk = sock->sk;
894 int err = 0;
895
896 /* This should really check to make sure
897 * the socket is a TCP socket. (WHY AC...)
898 */
899 how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
900 1->2 bit 2 snds.
901 2->3 */
902 if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */
903 return -EINVAL;
904
905 lock_sock(sk);
906 if (sock->state == SS_CONNECTING) {
907 if ((1 << sk->sk_state) &
908 (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
909 sock->state = SS_DISCONNECTING;
910 else
911 sock->state = SS_CONNECTED;
912 }
913
914 switch (sk->sk_state) {
915 case TCP_CLOSE:
916 err = -ENOTCONN;
917 /* Hack to wake up other listeners, who can poll for
918 EPOLLHUP, even on eg. unconnected UDP sockets -- RR */
919 fallthrough;
920 default:
921 WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | how);
922 if (sk->sk_prot->shutdown)
923 sk->sk_prot->shutdown(sk, how);
924 break;
925
926 /* Remaining two branches are temporary solution for missing
927 * close() in multithreaded environment. It is _not_ a good idea,
928 * but we have no choice until close() is repaired at VFS level.
929 */
930 case TCP_LISTEN:
931 if (!(how & RCV_SHUTDOWN))
932 break;
933 fallthrough;
934 case TCP_SYN_SENT:
935 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
936 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
937 break;
938 }
939
940 /* Wake up anyone sleeping in poll. */
941 sk->sk_state_change(sk);
942 release_sock(sk);
943 return err;
944}
945EXPORT_SYMBOL(inet_shutdown);
946
947/*
948 * ioctl() calls you can issue on an INET socket. Most of these are
949 * device configuration and stuff and very rarely used. Some ioctls
950 * pass on to the socket itself.
951 *
952 * NOTE: I like the idea of a module for the config stuff. ie ifconfig
953 * loads the devconfigure module does its configuring and unloads it.
954 * There's a good 20K of config code hanging around the kernel.
955 */
956
957int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
958{
959 struct sock *sk = sock->sk;
960 int err = 0;
961 struct net *net = sock_net(sk);
962 void __user *p = (void __user *)arg;
963 struct ifreq ifr;
964 struct rtentry rt;
965
966 switch (cmd) {
967 case SIOCADDRT:
968 case SIOCDELRT:
969 if (copy_from_user(to: &rt, from: p, n: sizeof(struct rtentry)))
970 return -EFAULT;
971 err = ip_rt_ioctl(net, cmd, rt: &rt);
972 break;
973 case SIOCRTMSG:
974 err = -EINVAL;
975 break;
976 case SIOCDARP:
977 case SIOCGARP:
978 case SIOCSARP:
979 err = arp_ioctl(net, cmd, arg: (void __user *)arg);
980 break;
981 case SIOCGIFADDR:
982 case SIOCGIFBRDADDR:
983 case SIOCGIFNETMASK:
984 case SIOCGIFDSTADDR:
985 case SIOCGIFPFLAGS:
986 if (get_user_ifreq(ifr: &ifr, NULL, arg: p))
987 return -EFAULT;
988 err = devinet_ioctl(net, cmd, &ifr);
989 if (!err && put_user_ifreq(ifr: &ifr, arg: p))
990 err = -EFAULT;
991 break;
992
993 case SIOCSIFADDR:
994 case SIOCSIFBRDADDR:
995 case SIOCSIFNETMASK:
996 case SIOCSIFDSTADDR:
997 case SIOCSIFPFLAGS:
998 case SIOCSIFFLAGS:
999 if (get_user_ifreq(ifr: &ifr, NULL, arg: p))
1000 return -EFAULT;
1001 err = devinet_ioctl(net, cmd, &ifr);
1002 break;
1003 default:
1004 if (sk->sk_prot->ioctl)
1005 err = sk_ioctl(sk, cmd, arg: (void __user *)arg);
1006 else
1007 err = -ENOIOCTLCMD;
1008 break;
1009 }
1010 return err;
1011}
1012EXPORT_SYMBOL(inet_ioctl);
1013
1014#ifdef CONFIG_COMPAT
1015static int inet_compat_routing_ioctl(struct sock *sk, unsigned int cmd,
1016 struct compat_rtentry __user *ur)
1017{
1018 compat_uptr_t rtdev;
1019 struct rtentry rt;
1020
1021 if (copy_from_user(to: &rt.rt_dst, from: &ur->rt_dst,
1022 n: 3 * sizeof(struct sockaddr)) ||
1023 get_user(rt.rt_flags, &ur->rt_flags) ||
1024 get_user(rt.rt_metric, &ur->rt_metric) ||
1025 get_user(rt.rt_mtu, &ur->rt_mtu) ||
1026 get_user(rt.rt_window, &ur->rt_window) ||
1027 get_user(rt.rt_irtt, &ur->rt_irtt) ||
1028 get_user(rtdev, &ur->rt_dev))
1029 return -EFAULT;
1030
1031 rt.rt_dev = compat_ptr(uptr: rtdev);
1032 return ip_rt_ioctl(sock_net(sk), cmd, rt: &rt);
1033}
1034
1035static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1036{
1037 void __user *argp = compat_ptr(uptr: arg);
1038 struct sock *sk = sock->sk;
1039
1040 switch (cmd) {
1041 case SIOCADDRT:
1042 case SIOCDELRT:
1043 return inet_compat_routing_ioctl(sk, cmd, ur: argp);
1044 default:
1045 if (!sk->sk_prot->compat_ioctl)
1046 return -ENOIOCTLCMD;
1047 return sk->sk_prot->compat_ioctl(sk, cmd, arg);
1048 }
1049}
1050#endif /* CONFIG_COMPAT */
1051
1052const struct proto_ops inet_stream_ops = {
1053 .family = PF_INET,
1054 .owner = THIS_MODULE,
1055 .release = inet_release,
1056 .bind = inet_bind,
1057 .connect = inet_stream_connect,
1058 .socketpair = sock_no_socketpair,
1059 .accept = inet_accept,
1060 .getname = inet_getname,
1061 .poll = tcp_poll,
1062 .ioctl = inet_ioctl,
1063 .gettstamp = sock_gettstamp,
1064 .listen = inet_listen,
1065 .shutdown = inet_shutdown,
1066 .setsockopt = sock_common_setsockopt,
1067 .getsockopt = sock_common_getsockopt,
1068 .sendmsg = inet_sendmsg,
1069 .recvmsg = inet_recvmsg,
1070#ifdef CONFIG_MMU
1071 .mmap = tcp_mmap,
1072#endif
1073 .splice_eof = inet_splice_eof,
1074 .splice_read = tcp_splice_read,
1075 .read_sock = tcp_read_sock,
1076 .read_skb = tcp_read_skb,
1077 .sendmsg_locked = tcp_sendmsg_locked,
1078 .peek_len = tcp_peek_len,
1079#ifdef CONFIG_COMPAT
1080 .compat_ioctl = inet_compat_ioctl,
1081#endif
1082 .set_rcvlowat = tcp_set_rcvlowat,
1083};
1084EXPORT_SYMBOL(inet_stream_ops);
1085
1086const struct proto_ops inet_dgram_ops = {
1087 .family = PF_INET,
1088 .owner = THIS_MODULE,
1089 .release = inet_release,
1090 .bind = inet_bind,
1091 .connect = inet_dgram_connect,
1092 .socketpair = sock_no_socketpair,
1093 .accept = sock_no_accept,
1094 .getname = inet_getname,
1095 .poll = udp_poll,
1096 .ioctl = inet_ioctl,
1097 .gettstamp = sock_gettstamp,
1098 .listen = sock_no_listen,
1099 .shutdown = inet_shutdown,
1100 .setsockopt = sock_common_setsockopt,
1101 .getsockopt = sock_common_getsockopt,
1102 .sendmsg = inet_sendmsg,
1103 .read_skb = udp_read_skb,
1104 .recvmsg = inet_recvmsg,
1105 .mmap = sock_no_mmap,
1106 .splice_eof = inet_splice_eof,
1107 .set_peek_off = udp_set_peek_off,
1108#ifdef CONFIG_COMPAT
1109 .compat_ioctl = inet_compat_ioctl,
1110#endif
1111};
1112EXPORT_SYMBOL(inet_dgram_ops);
1113
1114/*
1115 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
1116 * udp_poll
1117 */
1118static const struct proto_ops inet_sockraw_ops = {
1119 .family = PF_INET,
1120 .owner = THIS_MODULE,
1121 .release = inet_release,
1122 .bind = inet_bind,
1123 .connect = inet_dgram_connect,
1124 .socketpair = sock_no_socketpair,
1125 .accept = sock_no_accept,
1126 .getname = inet_getname,
1127 .poll = datagram_poll,
1128 .ioctl = inet_ioctl,
1129 .gettstamp = sock_gettstamp,
1130 .listen = sock_no_listen,
1131 .shutdown = inet_shutdown,
1132 .setsockopt = sock_common_setsockopt,
1133 .getsockopt = sock_common_getsockopt,
1134 .sendmsg = inet_sendmsg,
1135 .recvmsg = inet_recvmsg,
1136 .mmap = sock_no_mmap,
1137 .splice_eof = inet_splice_eof,
1138#ifdef CONFIG_COMPAT
1139 .compat_ioctl = inet_compat_ioctl,
1140#endif
1141};
1142
1143static const struct net_proto_family inet_family_ops = {
1144 .family = PF_INET,
1145 .create = inet_create,
1146 .owner = THIS_MODULE,
1147};
1148
1149/* Upon startup we insert all the elements in inetsw_array[] into
1150 * the linked list inetsw.
1151 */
1152static struct inet_protosw inetsw_array[] =
1153{
1154 {
1155 .type = SOCK_STREAM,
1156 .protocol = IPPROTO_TCP,
1157 .prot = &tcp_prot,
1158 .ops = &inet_stream_ops,
1159 .flags = INET_PROTOSW_PERMANENT |
1160 INET_PROTOSW_ICSK,
1161 },
1162
1163 {
1164 .type = SOCK_DGRAM,
1165 .protocol = IPPROTO_UDP,
1166 .prot = &udp_prot,
1167 .ops = &inet_dgram_ops,
1168 .flags = INET_PROTOSW_PERMANENT,
1169 },
1170
1171 {
1172 .type = SOCK_DGRAM,
1173 .protocol = IPPROTO_ICMP,
1174 .prot = &ping_prot,
1175 .ops = &inet_sockraw_ops,
1176 .flags = INET_PROTOSW_REUSE,
1177 },
1178
1179 {
1180 .type = SOCK_RAW,
1181 .protocol = IPPROTO_IP, /* wild card */
1182 .prot = &raw_prot,
1183 .ops = &inet_sockraw_ops,
1184 .flags = INET_PROTOSW_REUSE,
1185 }
1186};
1187
1188#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1189
1190void inet_register_protosw(struct inet_protosw *p)
1191{
1192 struct list_head *lh;
1193 struct inet_protosw *answer;
1194 int protocol = p->protocol;
1195 struct list_head *last_perm;
1196
1197 spin_lock_bh(lock: &inetsw_lock);
1198
1199 if (p->type >= SOCK_MAX)
1200 goto out_illegal;
1201
1202 /* If we are trying to override a permanent protocol, bail. */
1203 last_perm = &inetsw[p->type];
1204 list_for_each(lh, &inetsw[p->type]) {
1205 answer = list_entry(lh, struct inet_protosw, list);
1206 /* Check only the non-wild match. */
1207 if ((INET_PROTOSW_PERMANENT & answer->flags) == 0)
1208 break;
1209 if (protocol == answer->protocol)
1210 goto out_permanent;
1211 last_perm = lh;
1212 }
1213
1214 /* Add the new entry after the last permanent entry if any, so that
1215 * the new entry does not override a permanent entry when matched with
1216 * a wild-card protocol. But it is allowed to override any existing
1217 * non-permanent entry. This means that when we remove this entry, the
1218 * system automatically returns to the old behavior.
1219 */
1220 list_add_rcu(new: &p->list, head: last_perm);
1221out:
1222 spin_unlock_bh(lock: &inetsw_lock);
1223
1224 return;
1225
1226out_permanent:
1227 pr_err("Attempt to override permanent protocol %d\n", protocol);
1228 goto out;
1229
1230out_illegal:
1231 pr_err("Ignoring attempt to register invalid socket type %d\n",
1232 p->type);
1233 goto out;
1234}
1235EXPORT_SYMBOL(inet_register_protosw);
1236
1237void inet_unregister_protosw(struct inet_protosw *p)
1238{
1239 if (INET_PROTOSW_PERMANENT & p->flags) {
1240 pr_err("Attempt to unregister permanent protocol %d\n",
1241 p->protocol);
1242 } else {
1243 spin_lock_bh(lock: &inetsw_lock);
1244 list_del_rcu(entry: &p->list);
1245 spin_unlock_bh(lock: &inetsw_lock);
1246
1247 synchronize_net();
1248 }
1249}
1250EXPORT_SYMBOL(inet_unregister_protosw);
1251
1252static int inet_sk_reselect_saddr(struct sock *sk)
1253{
1254 struct inet_sock *inet = inet_sk(sk);
1255 __be32 old_saddr = inet->inet_saddr;
1256 __be32 daddr = inet->inet_daddr;
1257 struct flowi4 *fl4;
1258 struct rtable *rt;
1259 __be32 new_saddr;
1260 struct ip_options_rcu *inet_opt;
1261 int err;
1262
1263 inet_opt = rcu_dereference_protected(inet->inet_opt,
1264 lockdep_sock_is_held(sk));
1265 if (inet_opt && inet_opt->opt.srr)
1266 daddr = inet_opt->opt.faddr;
1267
1268 /* Query new route. */
1269 fl4 = &inet->cork.fl.u.ip4;
1270 rt = ip_route_connect(fl4, dst: daddr, src: 0, oif: sk->sk_bound_dev_if,
1271 protocol: sk->sk_protocol, sport: inet->inet_sport,
1272 dport: inet->inet_dport, sk);
1273 if (IS_ERR(ptr: rt))
1274 return PTR_ERR(ptr: rt);
1275
1276 new_saddr = fl4->saddr;
1277
1278 if (new_saddr == old_saddr) {
1279 sk_setup_caps(sk, dst: &rt->dst);
1280 return 0;
1281 }
1282
1283 err = inet_bhash2_update_saddr(sk, saddr: &new_saddr, AF_INET);
1284 if (err) {
1285 ip_rt_put(rt);
1286 return err;
1287 }
1288
1289 sk_setup_caps(sk, dst: &rt->dst);
1290
1291 if (READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) > 1) {
1292 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1293 __func__, &old_saddr, &new_saddr);
1294 }
1295
1296 /*
1297 * XXX The only one ugly spot where we need to
1298 * XXX really change the sockets identity after
1299 * XXX it has entered the hashes. -DaveM
1300 *
1301 * Besides that, it does not check for connection
1302 * uniqueness. Wait for troubles.
1303 */
1304 return __sk_prot_rehash(sk);
1305}
1306
1307int inet_sk_rebuild_header(struct sock *sk)
1308{
1309 struct inet_sock *inet = inet_sk(sk);
1310 struct rtable *rt = (struct rtable *)__sk_dst_check(sk, cookie: 0);
1311 __be32 daddr;
1312 struct ip_options_rcu *inet_opt;
1313 struct flowi4 *fl4;
1314 int err;
1315
1316 /* Route is OK, nothing to do. */
1317 if (rt)
1318 return 0;
1319
1320 /* Reroute. */
1321 rcu_read_lock();
1322 inet_opt = rcu_dereference(inet->inet_opt);
1323 daddr = inet->inet_daddr;
1324 if (inet_opt && inet_opt->opt.srr)
1325 daddr = inet_opt->opt.faddr;
1326 rcu_read_unlock();
1327 fl4 = &inet->cork.fl.u.ip4;
1328 rt = ip_route_output_ports(net: sock_net(sk), fl4, sk, daddr, saddr: inet->inet_saddr,
1329 dport: inet->inet_dport, sport: inet->inet_sport,
1330 proto: sk->sk_protocol, tos: ip_sock_rt_tos(sk),
1331 oif: sk->sk_bound_dev_if);
1332 if (!IS_ERR(ptr: rt)) {
1333 err = 0;
1334 sk_setup_caps(sk, dst: &rt->dst);
1335 } else {
1336 err = PTR_ERR(ptr: rt);
1337
1338 /* Routing failed... */
1339 sk->sk_route_caps = 0;
1340 /*
1341 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1342 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1343 */
1344 if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) ||
1345 sk->sk_state != TCP_SYN_SENT ||
1346 (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1347 (err = inet_sk_reselect_saddr(sk)) != 0)
1348 WRITE_ONCE(sk->sk_err_soft, -err);
1349 }
1350
1351 return err;
1352}
1353EXPORT_SYMBOL(inet_sk_rebuild_header);
1354
1355void inet_sk_set_state(struct sock *sk, int state)
1356{
1357 trace_inet_sock_set_state(sk, oldstate: sk->sk_state, newstate: state);
1358 sk->sk_state = state;
1359}
1360EXPORT_SYMBOL(inet_sk_set_state);
1361
1362void inet_sk_state_store(struct sock *sk, int newstate)
1363{
1364 trace_inet_sock_set_state(sk, oldstate: sk->sk_state, newstate);
1365 smp_store_release(&sk->sk_state, newstate);
1366}
1367
1368struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1369 netdev_features_t features)
1370{
1371 bool udpfrag = false, fixedid = false, gso_partial, encap;
1372 struct sk_buff *segs = ERR_PTR(error: -EINVAL);
1373 const struct net_offload *ops;
1374 unsigned int offset = 0;
1375 struct iphdr *iph;
1376 int proto, tot_len;
1377 int nhoff;
1378 int ihl;
1379 int id;
1380
1381 skb_reset_network_header(skb);
1382 nhoff = skb_network_header(skb) - skb_mac_header(skb);
1383 if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1384 goto out;
1385
1386 iph = ip_hdr(skb);
1387 ihl = iph->ihl * 4;
1388 if (ihl < sizeof(*iph))
1389 goto out;
1390
1391 id = ntohs(iph->id);
1392 proto = iph->protocol;
1393
1394 /* Warning: after this point, iph might be no longer valid */
1395 if (unlikely(!pskb_may_pull(skb, ihl)))
1396 goto out;
1397 __skb_pull(skb, len: ihl);
1398
1399 encap = SKB_GSO_CB(skb)->encap_level > 0;
1400 if (encap)
1401 features &= skb->dev->hw_enc_features;
1402 SKB_GSO_CB(skb)->encap_level += ihl;
1403
1404 skb_reset_transport_header(skb);
1405
1406 segs = ERR_PTR(error: -EPROTONOSUPPORT);
1407
1408 if (!skb->encapsulation || encap) {
1409 udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
1410 fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID);
1411
1412 /* fixed ID is invalid if DF bit is not set */
1413 if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF)))
1414 goto out;
1415 }
1416
1417 ops = rcu_dereference(inet_offloads[proto]);
1418 if (likely(ops && ops->callbacks.gso_segment)) {
1419 segs = ops->callbacks.gso_segment(skb, features);
1420 if (!segs)
1421 skb->network_header = skb_mac_header(skb) + nhoff - skb->head;
1422 }
1423
1424 if (IS_ERR_OR_NULL(ptr: segs))
1425 goto out;
1426
1427 gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
1428
1429 skb = segs;
1430 do {
1431 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1432 if (udpfrag) {
1433 iph->frag_off = htons(offset >> 3);
1434 if (skb->next)
1435 iph->frag_off |= htons(IP_MF);
1436 offset += skb->len - nhoff - ihl;
1437 tot_len = skb->len - nhoff;
1438 } else if (skb_is_gso(skb)) {
1439 if (!fixedid) {
1440 iph->id = htons(id);
1441 id += skb_shinfo(skb)->gso_segs;
1442 }
1443
1444 if (gso_partial)
1445 tot_len = skb_shinfo(skb)->gso_size +
1446 SKB_GSO_CB(skb)->data_offset +
1447 skb->head - (unsigned char *)iph;
1448 else
1449 tot_len = skb->len - nhoff;
1450 } else {
1451 if (!fixedid)
1452 iph->id = htons(id++);
1453 tot_len = skb->len - nhoff;
1454 }
1455 iph->tot_len = htons(tot_len);
1456 ip_send_check(ip: iph);
1457 if (encap)
1458 skb_reset_inner_headers(skb);
1459 skb->network_header = (u8 *)iph - skb->head;
1460 skb_reset_mac_len(skb);
1461 } while ((skb = skb->next));
1462
1463out:
1464 return segs;
1465}
1466
1467static struct sk_buff *ipip_gso_segment(struct sk_buff *skb,
1468 netdev_features_t features)
1469{
1470 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
1471 return ERR_PTR(error: -EINVAL);
1472
1473 return inet_gso_segment(skb, features);
1474}
1475
1476struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
1477{
1478 const struct net_offload *ops;
1479 struct sk_buff *pp = NULL;
1480 const struct iphdr *iph;
1481 struct sk_buff *p;
1482 unsigned int hlen;
1483 unsigned int off;
1484 unsigned int id;
1485 int flush = 1;
1486 int proto;
1487
1488 off = skb_gro_offset(skb);
1489 hlen = off + sizeof(*iph);
1490 iph = skb_gro_header(skb, hlen, offset: off);
1491 if (unlikely(!iph))
1492 goto out;
1493
1494 proto = iph->protocol;
1495
1496 ops = rcu_dereference(inet_offloads[proto]);
1497 if (!ops || !ops->callbacks.gro_receive)
1498 goto out;
1499
1500 if (*(u8 *)iph != 0x45)
1501 goto out;
1502
1503 if (ip_is_fragment(iph))
1504 goto out;
1505
1506 if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1507 goto out;
1508
1509 NAPI_GRO_CB(skb)->proto = proto;
1510 id = ntohl(*(__be32 *)&iph->id);
1511 flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
1512 id >>= 16;
1513
1514 list_for_each_entry(p, head, list) {
1515 struct iphdr *iph2;
1516 u16 flush_id;
1517
1518 if (!NAPI_GRO_CB(p)->same_flow)
1519 continue;
1520
1521 iph2 = (struct iphdr *)(p->data + off);
1522 /* The above works because, with the exception of the top
1523 * (inner most) layer, we only aggregate pkts with the same
1524 * hdr length so all the hdrs we'll need to verify will start
1525 * at the same offset.
1526 */
1527 if ((iph->protocol ^ iph2->protocol) |
1528 ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1529 ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1530 NAPI_GRO_CB(p)->same_flow = 0;
1531 continue;
1532 }
1533
1534 /* All fields must match except length and checksum. */
1535 NAPI_GRO_CB(p)->flush |=
1536 (iph->ttl ^ iph2->ttl) |
1537 (iph->tos ^ iph2->tos) |
1538 ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF));
1539
1540 NAPI_GRO_CB(p)->flush |= flush;
1541
1542 /* We need to store of the IP ID check to be included later
1543 * when we can verify that this packet does in fact belong
1544 * to a given flow.
1545 */
1546 flush_id = (u16)(id - ntohs(iph2->id));
1547
1548 /* This bit of code makes it much easier for us to identify
1549 * the cases where we are doing atomic vs non-atomic IP ID
1550 * checks. Specifically an atomic check can return IP ID
1551 * values 0 - 0xFFFF, while a non-atomic check can only
1552 * return 0 or 0xFFFF.
1553 */
1554 if (!NAPI_GRO_CB(p)->is_atomic ||
1555 !(iph->frag_off & htons(IP_DF))) {
1556 flush_id ^= NAPI_GRO_CB(p)->count;
1557 flush_id = flush_id ? 0xFFFF : 0;
1558 }
1559
1560 /* If the previous IP ID value was based on an atomic
1561 * datagram we can overwrite the value and ignore it.
1562 */
1563 if (NAPI_GRO_CB(skb)->is_atomic)
1564 NAPI_GRO_CB(p)->flush_id = flush_id;
1565 else
1566 NAPI_GRO_CB(p)->flush_id |= flush_id;
1567 }
1568
1569 NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF));
1570 NAPI_GRO_CB(skb)->flush |= flush;
1571 skb_set_network_header(skb, offset: off);
1572 /* The above will be needed by the transport layer if there is one
1573 * immediately following this IP hdr.
1574 */
1575
1576 /* Note : No need to call skb_gro_postpull_rcsum() here,
1577 * as we already checked checksum over ipv4 header was 0
1578 */
1579 skb_gro_pull(skb, len: sizeof(*iph));
1580 skb_set_transport_header(skb, offset: skb_gro_offset(skb));
1581
1582 pp = indirect_call_gro_receive(tcp4_gro_receive, udp4_gro_receive,
1583 ops->callbacks.gro_receive, head, skb);
1584
1585out:
1586 skb_gro_flush_final(skb, pp, flush);
1587
1588 return pp;
1589}
1590
1591static struct sk_buff *ipip_gro_receive(struct list_head *head,
1592 struct sk_buff *skb)
1593{
1594 if (NAPI_GRO_CB(skb)->encap_mark) {
1595 NAPI_GRO_CB(skb)->flush = 1;
1596 return NULL;
1597 }
1598
1599 NAPI_GRO_CB(skb)->encap_mark = 1;
1600
1601 return inet_gro_receive(head, skb);
1602}
1603
1604#define SECONDS_PER_DAY 86400
1605
1606/* inet_current_timestamp - Return IP network timestamp
1607 *
1608 * Return milliseconds since midnight in network byte order.
1609 */
1610__be32 inet_current_timestamp(void)
1611{
1612 u32 secs;
1613 u32 msecs;
1614 struct timespec64 ts;
1615
1616 ktime_get_real_ts64(tv: &ts);
1617
1618 /* Get secs since midnight. */
1619 (void)div_u64_rem(dividend: ts.tv_sec, SECONDS_PER_DAY, remainder: &secs);
1620 /* Convert to msecs. */
1621 msecs = secs * MSEC_PER_SEC;
1622 /* Convert nsec to msec. */
1623 msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;
1624
1625 /* Convert to network byte order. */
1626 return htonl(msecs);
1627}
1628EXPORT_SYMBOL(inet_current_timestamp);
1629
1630int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
1631{
1632 unsigned int family = READ_ONCE(sk->sk_family);
1633
1634 if (family == AF_INET)
1635 return ip_recv_error(sk, msg, len, addr_len);
1636#if IS_ENABLED(CONFIG_IPV6)
1637 if (family == AF_INET6)
1638 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
1639#endif
1640 return -EINVAL;
1641}
1642EXPORT_SYMBOL(inet_recv_error);
1643
1644int inet_gro_complete(struct sk_buff *skb, int nhoff)
1645{
1646 struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1647 const struct net_offload *ops;
1648 __be16 totlen = iph->tot_len;
1649 int proto = iph->protocol;
1650 int err = -ENOSYS;
1651
1652 if (skb->encapsulation) {
1653 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IP));
1654 skb_set_inner_network_header(skb, offset: nhoff);
1655 }
1656
1657 iph_set_totlen(iph, len: skb->len - nhoff);
1658 csum_replace2(sum: &iph->check, old: totlen, new: iph->tot_len);
1659
1660 ops = rcu_dereference(inet_offloads[proto]);
1661 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1662 goto out;
1663
1664 /* Only need to add sizeof(*iph) to get to the next hdr below
1665 * because any hdr with option will have been flushed in
1666 * inet_gro_receive().
1667 */
1668 err = INDIRECT_CALL_2(ops->callbacks.gro_complete,
1669 tcp4_gro_complete, udp4_gro_complete,
1670 skb, nhoff + sizeof(*iph));
1671
1672out:
1673 return err;
1674}
1675
1676static int ipip_gro_complete(struct sk_buff *skb, int nhoff)
1677{
1678 skb->encapsulation = 1;
1679 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
1680 return inet_gro_complete(skb, nhoff);
1681}
1682
1683int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1684 unsigned short type, unsigned char protocol,
1685 struct net *net)
1686{
1687 struct socket *sock;
1688 int rc = sock_create_kern(net, family, type, proto: protocol, res: &sock);
1689
1690 if (rc == 0) {
1691 *sk = sock->sk;
1692 (*sk)->sk_allocation = GFP_ATOMIC;
1693 (*sk)->sk_use_task_frag = false;
1694 /*
1695 * Unhash it so that IP input processing does not even see it,
1696 * we do not wish this socket to see incoming packets.
1697 */
1698 (*sk)->sk_prot->unhash(*sk);
1699 }
1700 return rc;
1701}
1702EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1703
1704unsigned long snmp_fold_field(void __percpu *mib, int offt)
1705{
1706 unsigned long res = 0;
1707 int i;
1708
1709 for_each_possible_cpu(i)
1710 res += snmp_get_cpu_field(mib, cpu: i, offt);
1711 return res;
1712}
1713EXPORT_SYMBOL_GPL(snmp_fold_field);
1714
1715#if BITS_PER_LONG==32
1716
1717u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt,
1718 size_t syncp_offset)
1719{
1720 void *bhptr;
1721 struct u64_stats_sync *syncp;
1722 u64 v;
1723 unsigned int start;
1724
1725 bhptr = per_cpu_ptr(mib, cpu);
1726 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1727 do {
1728 start = u64_stats_fetch_begin(syncp);
1729 v = *(((u64 *)bhptr) + offt);
1730 } while (u64_stats_fetch_retry(syncp, start));
1731
1732 return v;
1733}
1734EXPORT_SYMBOL_GPL(snmp_get_cpu_field64);
1735
1736u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1737{
1738 u64 res = 0;
1739 int cpu;
1740
1741 for_each_possible_cpu(cpu) {
1742 res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset);
1743 }
1744 return res;
1745}
1746EXPORT_SYMBOL_GPL(snmp_fold_field64);
1747#endif
1748
1749#ifdef CONFIG_IP_MULTICAST
1750static const struct net_protocol igmp_protocol = {
1751 .handler = igmp_rcv,
1752};
1753#endif
1754
1755static const struct net_protocol icmp_protocol = {
1756 .handler = icmp_rcv,
1757 .err_handler = icmp_err,
1758 .no_policy = 1,
1759};
1760
1761static __net_init int ipv4_mib_init_net(struct net *net)
1762{
1763 int i;
1764
1765 net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1766 if (!net->mib.tcp_statistics)
1767 goto err_tcp_mib;
1768 net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1769 if (!net->mib.ip_statistics)
1770 goto err_ip_mib;
1771
1772 for_each_possible_cpu(i) {
1773 struct ipstats_mib *af_inet_stats;
1774 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1775 u64_stats_init(syncp: &af_inet_stats->syncp);
1776 }
1777
1778 net->mib.net_statistics = alloc_percpu(struct linux_mib);
1779 if (!net->mib.net_statistics)
1780 goto err_net_mib;
1781 net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1782 if (!net->mib.udp_statistics)
1783 goto err_udp_mib;
1784 net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1785 if (!net->mib.udplite_statistics)
1786 goto err_udplite_mib;
1787 net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1788 if (!net->mib.icmp_statistics)
1789 goto err_icmp_mib;
1790 net->mib.icmpmsg_statistics = kzalloc(size: sizeof(struct icmpmsg_mib),
1791 GFP_KERNEL);
1792 if (!net->mib.icmpmsg_statistics)
1793 goto err_icmpmsg_mib;
1794
1795 tcp_mib_init(net);
1796 return 0;
1797
1798err_icmpmsg_mib:
1799 free_percpu(pdata: net->mib.icmp_statistics);
1800err_icmp_mib:
1801 free_percpu(pdata: net->mib.udplite_statistics);
1802err_udplite_mib:
1803 free_percpu(pdata: net->mib.udp_statistics);
1804err_udp_mib:
1805 free_percpu(pdata: net->mib.net_statistics);
1806err_net_mib:
1807 free_percpu(pdata: net->mib.ip_statistics);
1808err_ip_mib:
1809 free_percpu(pdata: net->mib.tcp_statistics);
1810err_tcp_mib:
1811 return -ENOMEM;
1812}
1813
1814static __net_exit void ipv4_mib_exit_net(struct net *net)
1815{
1816 kfree(objp: net->mib.icmpmsg_statistics);
1817 free_percpu(pdata: net->mib.icmp_statistics);
1818 free_percpu(pdata: net->mib.udplite_statistics);
1819 free_percpu(pdata: net->mib.udp_statistics);
1820 free_percpu(pdata: net->mib.net_statistics);
1821 free_percpu(pdata: net->mib.ip_statistics);
1822 free_percpu(pdata: net->mib.tcp_statistics);
1823#ifdef CONFIG_MPTCP
1824 /* allocated on demand, see mptcp_init_sock() */
1825 free_percpu(pdata: net->mib.mptcp_statistics);
1826#endif
1827}
1828
1829static __net_initdata struct pernet_operations ipv4_mib_ops = {
1830 .init = ipv4_mib_init_net,
1831 .exit = ipv4_mib_exit_net,
1832};
1833
1834static int __init init_ipv4_mibs(void)
1835{
1836 return register_pernet_subsys(&ipv4_mib_ops);
1837}
1838
1839static __net_init int inet_init_net(struct net *net)
1840{
1841 /*
1842 * Set defaults for local port range
1843 */
1844 net->ipv4.ip_local_ports.range = 60999u << 16 | 32768u;
1845
1846 seqlock_init(&net->ipv4.ping_group_range.lock);
1847 /*
1848 * Sane defaults - nobody may create ping sockets.
1849 * Boot scripts should set this to distro-specific group.
1850 */
1851 net->ipv4.ping_group_range.range[0] = make_kgid(from: &init_user_ns, gid: 1);
1852 net->ipv4.ping_group_range.range[1] = make_kgid(from: &init_user_ns, gid: 0);
1853
1854 /* Default values for sysctl-controlled parameters.
1855 * We set them here, in case sysctl is not compiled.
1856 */
1857 net->ipv4.sysctl_ip_default_ttl = IPDEFTTL;
1858 net->ipv4.sysctl_ip_fwd_update_priority = 1;
1859 net->ipv4.sysctl_ip_dynaddr = 0;
1860 net->ipv4.sysctl_ip_early_demux = 1;
1861 net->ipv4.sysctl_udp_early_demux = 1;
1862 net->ipv4.sysctl_tcp_early_demux = 1;
1863 net->ipv4.sysctl_nexthop_compat_mode = 1;
1864#ifdef CONFIG_SYSCTL
1865 net->ipv4.sysctl_ip_prot_sock = PROT_SOCK;
1866#endif
1867
1868 /* Some igmp sysctl, whose values are always used */
1869 net->ipv4.sysctl_igmp_max_memberships = 20;
1870 net->ipv4.sysctl_igmp_max_msf = 10;
1871 /* IGMP reports for link-local multicast groups are enabled by default */
1872 net->ipv4.sysctl_igmp_llm_reports = 1;
1873 net->ipv4.sysctl_igmp_qrv = 2;
1874
1875 net->ipv4.sysctl_fib_notify_on_flag_change = 0;
1876
1877 return 0;
1878}
1879
1880static __net_initdata struct pernet_operations af_inet_ops = {
1881 .init = inet_init_net,
1882};
1883
1884static int __init init_inet_pernet_ops(void)
1885{
1886 return register_pernet_subsys(&af_inet_ops);
1887}
1888
1889static int ipv4_proc_init(void);
1890
1891/*
1892 * IP protocol layer initialiser
1893 */
1894
1895
1896static const struct net_offload ipip_offload = {
1897 .callbacks = {
1898 .gso_segment = ipip_gso_segment,
1899 .gro_receive = ipip_gro_receive,
1900 .gro_complete = ipip_gro_complete,
1901 },
1902};
1903
1904static int __init ipip_offload_init(void)
1905{
1906 return inet_add_offload(prot: &ipip_offload, IPPROTO_IPIP);
1907}
1908
1909static int __init ipv4_offload_init(void)
1910{
1911 /*
1912 * Add offloads
1913 */
1914 if (udpv4_offload_init() < 0)
1915 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1916 if (tcpv4_offload_init() < 0)
1917 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1918 if (ipip_offload_init() < 0)
1919 pr_crit("%s: Cannot add IPIP protocol offload\n", __func__);
1920
1921 net_hotdata.ip_packet_offload = (struct packet_offload) {
1922 .type = cpu_to_be16(ETH_P_IP),
1923 .callbacks = {
1924 .gso_segment = inet_gso_segment,
1925 .gro_receive = inet_gro_receive,
1926 .gro_complete = inet_gro_complete,
1927 },
1928 };
1929 dev_add_offload(po: &net_hotdata.ip_packet_offload);
1930 return 0;
1931}
1932
1933fs_initcall(ipv4_offload_init);
1934
1935static struct packet_type ip_packet_type __read_mostly = {
1936 .type = cpu_to_be16(ETH_P_IP),
1937 .func = ip_rcv,
1938 .list_func = ip_list_rcv,
1939};
1940
1941static int __init inet_init(void)
1942{
1943 struct inet_protosw *q;
1944 struct list_head *r;
1945 int rc;
1946
1947 sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
1948
1949 raw_hashinfo_init(hashinfo: &raw_v4_hashinfo);
1950
1951 rc = proto_register(prot: &tcp_prot, alloc_slab: 1);
1952 if (rc)
1953 goto out;
1954
1955 rc = proto_register(prot: &udp_prot, alloc_slab: 1);
1956 if (rc)
1957 goto out_unregister_tcp_proto;
1958
1959 rc = proto_register(prot: &raw_prot, alloc_slab: 1);
1960 if (rc)
1961 goto out_unregister_udp_proto;
1962
1963 rc = proto_register(prot: &ping_prot, alloc_slab: 1);
1964 if (rc)
1965 goto out_unregister_raw_proto;
1966
1967 /*
1968 * Tell SOCKET that we are alive...
1969 */
1970
1971 (void)sock_register(fam: &inet_family_ops);
1972
1973#ifdef CONFIG_SYSCTL
1974 ip_static_sysctl_init();
1975#endif
1976
1977 /*
1978 * Add all the base protocols.
1979 */
1980
1981 if (inet_add_protocol(prot: &icmp_protocol, IPPROTO_ICMP) < 0)
1982 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1983
1984 net_hotdata.udp_protocol = (struct net_protocol) {
1985 .handler = udp_rcv,
1986 .err_handler = udp_err,
1987 .no_policy = 1,
1988 };
1989 if (inet_add_protocol(prot: &net_hotdata.udp_protocol, IPPROTO_UDP) < 0)
1990 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1991
1992 net_hotdata.tcp_protocol = (struct net_protocol) {
1993 .handler = tcp_v4_rcv,
1994 .err_handler = tcp_v4_err,
1995 .no_policy = 1,
1996 .icmp_strict_tag_validation = 1,
1997 };
1998 if (inet_add_protocol(prot: &net_hotdata.tcp_protocol, IPPROTO_TCP) < 0)
1999 pr_crit("%s: Cannot add TCP protocol\n", __func__);
2000#ifdef CONFIG_IP_MULTICAST
2001 if (inet_add_protocol(prot: &igmp_protocol, IPPROTO_IGMP) < 0)
2002 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
2003#endif
2004
2005 /* Register the socket-side information for inet_create. */
2006 for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
2007 INIT_LIST_HEAD(list: r);
2008
2009 for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
2010 inet_register_protosw(q);
2011
2012 /*
2013 * Set the ARP module up
2014 */
2015
2016 arp_init();
2017
2018 /*
2019 * Set the IP module up
2020 */
2021
2022 ip_init();
2023
2024 /* Initialise per-cpu ipv4 mibs */
2025 if (init_ipv4_mibs())
2026 panic(fmt: "%s: Cannot init ipv4 mibs\n", __func__);
2027
2028 /* Setup TCP slab cache for open requests. */
2029 tcp_init();
2030
2031 /* Setup UDP memory threshold */
2032 udp_init();
2033
2034 /* Add UDP-Lite (RFC 3828) */
2035 udplite4_register();
2036
2037 raw_init();
2038
2039 ping_init();
2040
2041 /*
2042 * Set the ICMP layer up
2043 */
2044
2045 if (icmp_init() < 0)
2046 panic(fmt: "Failed to create the ICMP control socket.\n");
2047
2048 /*
2049 * Initialise the multicast router
2050 */
2051#if defined(CONFIG_IP_MROUTE)
2052 if (ip_mr_init())
2053 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
2054#endif
2055
2056 if (init_inet_pernet_ops())
2057 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
2058
2059 ipv4_proc_init();
2060
2061 ipfrag_init();
2062
2063 dev_add_pack(pt: &ip_packet_type);
2064
2065 ip_tunnel_core_init();
2066
2067 rc = 0;
2068out:
2069 return rc;
2070out_unregister_raw_proto:
2071 proto_unregister(prot: &raw_prot);
2072out_unregister_udp_proto:
2073 proto_unregister(prot: &udp_prot);
2074out_unregister_tcp_proto:
2075 proto_unregister(prot: &tcp_prot);
2076 goto out;
2077}
2078
2079fs_initcall(inet_init);
2080
2081/* ------------------------------------------------------------------------ */
2082
2083#ifdef CONFIG_PROC_FS
2084static int __init ipv4_proc_init(void)
2085{
2086 int rc = 0;
2087
2088 if (raw_proc_init())
2089 goto out_raw;
2090 if (tcp4_proc_init())
2091 goto out_tcp;
2092 if (udp4_proc_init())
2093 goto out_udp;
2094 if (ping_proc_init())
2095 goto out_ping;
2096 if (ip_misc_proc_init())
2097 goto out_misc;
2098out:
2099 return rc;
2100out_misc:
2101 ping_proc_exit();
2102out_ping:
2103 udp4_proc_exit();
2104out_udp:
2105 tcp4_proc_exit();
2106out_tcp:
2107 raw_proc_exit();
2108out_raw:
2109 rc = -ENOMEM;
2110 goto out;
2111}
2112
2113#else /* CONFIG_PROC_FS */
2114static int __init ipv4_proc_init(void)
2115{
2116 return 0;
2117}
2118#endif /* CONFIG_PROC_FS */
2119

source code of linux/net/ipv4/af_inet.c