Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* L2TPv3 IP encapsulation support
3 *
4 * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
5 */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9#include <asm/ioctls.h>
10#include <linux/icmp.h>
11#include <linux/module.h>
12#include <linux/skbuff.h>
13#include <linux/random.h>
14#include <linux/socket.h>
15#include <linux/l2tp.h>
16#include <linux/in.h>
17#include <net/sock.h>
18#include <net/ip.h>
19#include <net/icmp.h>
20#include <net/udp.h>
21#include <net/inet_common.h>
22#include <net/tcp_states.h>
23#include <net/protocol.h>
24#include <net/xfrm.h>
25#include <net/net_namespace.h>
26#include <net/netns/generic.h>
27
28#include "l2tp_core.h"
29
30/* per-net private data for this module */
31static unsigned int l2tp_ip_net_id;
32struct l2tp_ip_net {
33 rwlock_t l2tp_ip_lock;
34 struct hlist_head l2tp_ip_table;
35 struct hlist_head l2tp_ip_bind_table;
36};
37
38struct l2tp_ip_sock {
39 /* inet_sock has to be the first member of l2tp_ip_sock */
40 struct inet_sock inet;
41
42 u32 conn_id;
43 u32 peer_conn_id;
44};
45
46static struct l2tp_ip_sock *l2tp_ip_sk(const struct sock *sk)
47{
48 return (struct l2tp_ip_sock *)sk;
49}
50
51static struct l2tp_ip_net *l2tp_ip_pernet(const struct net *net)
52{
53 return net_generic(net, l2tp_ip_net_id);
54}
55
56static struct sock *__l2tp_ip_bind_lookup(const struct net *net, __be32 laddr,
57 __be32 raddr, int dif, u32 tunnel_id)
58{
59 struct l2tp_ip_net *pn = l2tp_ip_pernet(net);
60 struct sock *sk;
61
62 sk_for_each_bound(sk, &pn->l2tp_ip_bind_table) {
63 const struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk);
64 const struct inet_sock *inet = inet_sk(sk);
65 int bound_dev_if;
66
67 if (!net_eq(sock_net(sk), net))
68 continue;
69
70 bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
71 if (bound_dev_if && dif && bound_dev_if != dif)
72 continue;
73
74 if (inet->inet_rcv_saddr && laddr &&
75 inet->inet_rcv_saddr != laddr)
76 continue;
77
78 if (inet->inet_daddr && raddr && inet->inet_daddr != raddr)
79 continue;
80
81 if (l2tp->conn_id != tunnel_id)
82 continue;
83
84 goto found;
85 }
86
87 sk = NULL;
88found:
89 return sk;
90}
91
92/* When processing receive frames, there are two cases to
93 * consider. Data frames consist of a non-zero session-id and an
94 * optional cookie. Control frames consist of a regular L2TP header
95 * preceded by 32-bits of zeros.
96 *
97 * L2TPv3 Session Header Over IP
98 *
99 * 0 1 2 3
100 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
101 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
102 * | Session ID |
103 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
104 * | Cookie (optional, maximum 64 bits)...
105 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
106 * |
107 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
108 *
109 * L2TPv3 Control Message Header Over IP
110 *
111 * 0 1 2 3
112 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
113 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
114 * | (32 bits of zeros) |
115 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
116 * |T|L|x|x|S|x|x|x|x|x|x|x| Ver | Length |
117 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
118 * | Control Connection ID |
119 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
120 * | Ns | Nr |
121 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
122 *
123 * All control frames are passed to userspace.
124 */
125static int l2tp_ip_recv(struct sk_buff *skb)
126{
127 struct net *net = dev_net(skb->dev);
128 struct l2tp_ip_net *pn;
129 struct sock *sk;
130 u32 session_id;
131 u32 tunnel_id;
132 unsigned char *ptr, *optr;
133 struct l2tp_session *session;
134 struct l2tp_tunnel *tunnel = NULL;
135 struct iphdr *iph;
136
137 pn = l2tp_ip_pernet(net);
138
139 if (!pskb_may_pull(skb, 4))
140 goto discard;
141
142 /* Point to L2TP header */
143 optr = skb->data;
144 ptr = skb->data;
145 session_id = ntohl(*((__be32 *)ptr));
146 ptr += 4;
147
148 /* RFC3931: L2TP/IP packets have the first 4 bytes containing
149 * the session_id. If it is 0, the packet is a L2TP control
150 * frame and the session_id value can be discarded.
151 */
152 if (session_id == 0) {
153 __skb_pull(skb, 4);
154 goto pass_up;
155 }
156
157 /* Ok, this is a data packet. Lookup the session. */
158 session = l2tp_v3_session_get(net, NULL, session_id);
159 if (!session)
160 goto discard;
161
162 tunnel = session->tunnel;
163 if (!tunnel)
164 goto discard_sess;
165
166 if (l2tp_v3_ensure_opt_in_linear(session, skb, &ptr, &optr))
167 goto discard_sess;
168
169 l2tp_recv_common(session, skb, ptr, optr, 0, skb->len);
170 l2tp_session_put(session);
171
172 return 0;
173
174pass_up:
175 /* Get the tunnel_id from the L2TP header */
176 if (!pskb_may_pull(skb, 12))
177 goto discard;
178
179 if ((skb->data[0] & 0xc0) != 0xc0)
180 goto discard;
181
182 tunnel_id = ntohl(*(__be32 *)&skb->data[4]);
183 iph = (struct iphdr *)skb_network_header(skb);
184
185 read_lock_bh(&pn->l2tp_ip_lock);
186 sk = __l2tp_ip_bind_lookup(net, iph->daddr, iph->saddr, inet_iif(skb),
187 tunnel_id);
188 if (!sk) {
189 read_unlock_bh(&pn->l2tp_ip_lock);
190 goto discard;
191 }
192 sock_hold(sk);
193 read_unlock_bh(&pn->l2tp_ip_lock);
194
195 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
196 goto discard_put;
197
198 nf_reset_ct(skb);
199
200 return sk_receive_skb(sk, skb, 1);
201
202discard_sess:
203 l2tp_session_put(session);
204 goto discard;
205
206discard_put:
207 sock_put(sk);
208
209discard:
210 kfree_skb(skb);
211 return 0;
212}
213
214static int l2tp_ip_hash(struct sock *sk)
215{
216 struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));
217
218 if (sk_unhashed(sk)) {
219 write_lock_bh(&pn->l2tp_ip_lock);
220 sk_add_node(sk, &pn->l2tp_ip_table);
221 write_unlock_bh(&pn->l2tp_ip_lock);
222 }
223 return 0;
224}
225
226static void l2tp_ip_unhash(struct sock *sk)
227{
228 struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));
229
230 if (sk_unhashed(sk))
231 return;
232 write_lock_bh(&pn->l2tp_ip_lock);
233 sk_del_node_init(sk);
234 write_unlock_bh(&pn->l2tp_ip_lock);
235}
236
237static int l2tp_ip_open(struct sock *sk)
238{
239 /* Prevent autobind. We don't have ports. */
240 inet_sk(sk)->inet_num = IPPROTO_L2TP;
241
242 l2tp_ip_hash(sk);
243 return 0;
244}
245
246static void l2tp_ip_close(struct sock *sk, long timeout)
247{
248 struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));
249
250 write_lock_bh(&pn->l2tp_ip_lock);
251 hlist_del_init(&sk->sk_bind_node);
252 sk_del_node_init(sk);
253 write_unlock_bh(&pn->l2tp_ip_lock);
254 sk_common_release(sk);
255}
256
257static void l2tp_ip_destroy_sock(struct sock *sk)
258{
259 struct l2tp_tunnel *tunnel;
260
261 __skb_queue_purge(&sk->sk_write_queue);
262
263 tunnel = l2tp_sk_to_tunnel(sk);
264 if (tunnel) {
265 l2tp_tunnel_delete(tunnel);
266 l2tp_tunnel_put(tunnel);
267 }
268}
269
270static int l2tp_ip_bind(struct sock *sk, struct sockaddr_unsized *uaddr,
271 int addr_len)
272{
273 struct inet_sock *inet = inet_sk(sk);
274 struct sockaddr_l2tpip *addr = (struct sockaddr_l2tpip *)uaddr;
275 struct net *net = sock_net(sk);
276 struct l2tp_ip_net *pn;
277 int ret;
278 int chk_addr_ret;
279
280 if (addr_len < sizeof(struct sockaddr_l2tpip))
281 return -EINVAL;
282 if (addr->l2tp_family != AF_INET)
283 return -EINVAL;
284
285 lock_sock(sk);
286
287 ret = -EINVAL;
288 if (!sock_flag(sk, SOCK_ZAPPED))
289 goto out;
290
291 if (sk->sk_state != TCP_CLOSE)
292 goto out;
293
294 chk_addr_ret = inet_addr_type(net, addr->l2tp_addr.s_addr);
295 ret = -EADDRNOTAVAIL;
296 if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
297 chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
298 goto out;
299
300 if (addr->l2tp_addr.s_addr) {
301 inet->inet_rcv_saddr = addr->l2tp_addr.s_addr;
302 inet->inet_saddr = addr->l2tp_addr.s_addr;
303 }
304 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
305 inet->inet_saddr = 0; /* Use device */
306
307 pn = l2tp_ip_pernet(net);
308 write_lock_bh(&pn->l2tp_ip_lock);
309 if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr, 0,
310 sk->sk_bound_dev_if, addr->l2tp_conn_id)) {
311 write_unlock_bh(&pn->l2tp_ip_lock);
312 ret = -EADDRINUSE;
313 goto out;
314 }
315
316 sk_dst_reset(sk);
317 l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id;
318
319 sk_add_bind_node(sk, &pn->l2tp_ip_bind_table);
320 sk_del_node_init(sk);
321 write_unlock_bh(&pn->l2tp_ip_lock);
322
323 ret = 0;
324 sock_reset_flag(sk, SOCK_ZAPPED);
325
326out:
327 release_sock(sk);
328
329 return ret;
330}
331
332static int l2tp_ip_connect(struct sock *sk, struct sockaddr_unsized *uaddr,
333 int addr_len)
334{
335 struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;
336 struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));
337 int rc;
338
339 if (addr_len < sizeof(*lsa))
340 return -EINVAL;
341
342 if (ipv4_is_multicast(lsa->l2tp_addr.s_addr))
343 return -EINVAL;
344
345 lock_sock(sk);
346
347 /* Must bind first - autobinding does not work */
348 if (sock_flag(sk, SOCK_ZAPPED)) {
349 rc = -EINVAL;
350 goto out_sk;
351 }
352
353 rc = __ip4_datagram_connect(sk, uaddr, addr_len);
354 if (rc < 0)
355 goto out_sk;
356
357 l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
358
359 write_lock_bh(&pn->l2tp_ip_lock);
360 hlist_del_init(&sk->sk_bind_node);
361 sk_add_bind_node(sk, &pn->l2tp_ip_bind_table);
362 write_unlock_bh(&pn->l2tp_ip_lock);
363
364out_sk:
365 release_sock(sk);
366
367 return rc;
368}
369
370static int l2tp_ip_disconnect(struct sock *sk, int flags)
371{
372 if (sock_flag(sk, SOCK_ZAPPED))
373 return 0;
374
375 return __udp_disconnect(sk, flags);
376}
377
378static int l2tp_ip_getname(struct socket *sock, struct sockaddr *uaddr,
379 int peer)
380{
381 struct sock *sk = sock->sk;
382 struct inet_sock *inet = inet_sk(sk);
383 struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk);
384 struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;
385
386 memset(lsa, 0, sizeof(*lsa));
387 lsa->l2tp_family = AF_INET;
388 if (peer) {
389 if (!inet->inet_dport)
390 return -ENOTCONN;
391 lsa->l2tp_conn_id = lsk->peer_conn_id;
392 lsa->l2tp_addr.s_addr = inet->inet_daddr;
393 } else {
394 __be32 addr = inet->inet_rcv_saddr;
395
396 if (!addr)
397 addr = inet->inet_saddr;
398 lsa->l2tp_conn_id = lsk->conn_id;
399 lsa->l2tp_addr.s_addr = addr;
400 }
401 return sizeof(*lsa);
402}
403
404static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb)
405{
406 int rc;
407
408 /* Charge it to the socket, dropping if the queue is full. */
409 rc = sock_queue_rcv_skb(sk, skb);
410 if (rc < 0)
411 goto drop;
412
413 return 0;
414
415drop:
416 IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS);
417 kfree_skb(skb);
418 return 0;
419}
420
421/* Userspace will call sendmsg() on the tunnel socket to send L2TP
422 * control frames.
423 */
424static int l2tp_ip_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
425{
426 struct sk_buff *skb;
427 int rc;
428 struct inet_sock *inet = inet_sk(sk);
429 struct rtable *rt = NULL;
430 int connected = 0;
431 __be32 daddr;
432
433 lock_sock(sk);
434
435 rc = -ENOTCONN;
436 if (sock_flag(sk, SOCK_DEAD))
437 goto out;
438
439 /* Get and verify the address. */
440 if (msg->msg_name) {
441 DECLARE_SOCKADDR(struct sockaddr_l2tpip *, lip, msg->msg_name);
442
443 rc = -EINVAL;
444 if (msg->msg_namelen < sizeof(*lip))
445 goto out;
446
447 if (lip->l2tp_family != AF_INET) {
448 rc = -EAFNOSUPPORT;
449 if (lip->l2tp_family != AF_UNSPEC)
450 goto out;
451 }
452
453 daddr = lip->l2tp_addr.s_addr;
454 } else {
455 rc = -EDESTADDRREQ;
456 if (sk->sk_state != TCP_ESTABLISHED)
457 goto out;
458
459 connected = 1;
460 }
461
462 /* Allocate a socket buffer */
463 rc = -ENOMEM;
464 skb = sock_wmalloc(sk, 2 + NET_SKB_PAD + sizeof(struct iphdr) +
465 4 + len, 0, GFP_KERNEL);
466 if (!skb)
467 goto error;
468
469 /* Reserve space for headers, putting IP header on 4-byte boundary. */
470 skb_reserve(skb, 2 + NET_SKB_PAD);
471 skb_reset_network_header(skb);
472 skb_reserve(skb, sizeof(struct iphdr));
473 skb_reset_transport_header(skb);
474
475 /* Insert 0 session_id */
476 *((__be32 *)skb_put(skb, 4)) = 0;
477
478 /* Copy user data into skb */
479 rc = memcpy_from_msg(skb_put(skb, len), msg, len);
480 if (rc < 0) {
481 kfree_skb(skb);
482 goto error;
483 }
484
485 if (connected)
486 rt = dst_rtable(__sk_dst_check(sk, 0));
487
488 rcu_read_lock();
489 if (!rt) {
490 struct flowi4 *fl4 = &inet->cork.fl.u.ip4;
491
492 inet_sk_init_flowi4(inet, fl4);
493
494 /* Overwrite ->daddr if msg->msg_name was provided */
495 if (!connected)
496 fl4->daddr = daddr;
497
498 /* If this fails, retransmit mechanism of transport layer will
499 * keep trying until route appears or the connection times
500 * itself out.
501 */
502 rt = ip_route_output_flow(sock_net(sk), fl4, sk);
503 if (IS_ERR(rt))
504 goto no_route;
505 if (connected) {
506 sk_setup_caps(sk, &rt->dst);
507 } else {
508 skb_dst_set(skb, &rt->dst);
509 goto xmit;
510 }
511 }
512
513 /* We don't need to clone dst here, it is guaranteed to not disappear.
514 * __dev_xmit_skb() might force a refcount if needed.
515 */
516 skb_dst_set_noref(skb, &rt->dst);
517
518xmit:
519 /* Queue the packet to IP for output */
520 rc = ip_queue_xmit(sk, skb, &inet->cork.fl);
521 rcu_read_unlock();
522
523error:
524 if (rc >= 0)
525 rc = len;
526
527out:
528 release_sock(sk);
529 return rc;
530
531no_route:
532 rcu_read_unlock();
533 IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
534 kfree_skb(skb);
535 rc = -EHOSTUNREACH;
536 goto out;
537}
538
539static int l2tp_ip_recvmsg(struct sock *sk, struct msghdr *msg,
540 size_t len, int flags, int *addr_len)
541{
542 struct inet_sock *inet = inet_sk(sk);
543 size_t copied = 0;
544 int err = -EOPNOTSUPP;
545 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
546 struct sk_buff *skb;
547
548 if (flags & MSG_OOB)
549 goto out;
550
551 skb = skb_recv_datagram(sk, flags, &err);
552 if (!skb)
553 goto out;
554
555 copied = skb->len;
556 if (len < copied) {
557 msg->msg_flags |= MSG_TRUNC;
558 copied = len;
559 }
560
561 err = skb_copy_datagram_msg(skb, 0, msg, copied);
562 if (err)
563 goto done;
564
565 sock_recv_timestamp(msg, sk, skb);
566
567 /* Copy the address. */
568 if (sin) {
569 sin->sin_family = AF_INET;
570 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
571 sin->sin_port = 0;
572 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
573 *addr_len = sizeof(*sin);
574 }
575 if (inet_cmsg_flags(inet))
576 ip_cmsg_recv(msg, skb);
577 if (flags & MSG_TRUNC)
578 copied = skb->len;
579done:
580 skb_free_datagram(sk, skb);
581out:
582 return err ? err : copied;
583}
584
585int l2tp_ioctl(struct sock *sk, int cmd, int *karg)
586{
587 struct sk_buff *skb;
588
589 switch (cmd) {
590 case SIOCOUTQ:
591 *karg = sk_wmem_alloc_get(sk);
592 break;
593 case SIOCINQ:
594 spin_lock_bh(&sk->sk_receive_queue.lock);
595 skb = skb_peek(&sk->sk_receive_queue);
596 *karg = skb ? skb->len : 0;
597 spin_unlock_bh(&sk->sk_receive_queue.lock);
598 break;
599
600 default:
601 return -ENOIOCTLCMD;
602 }
603
604 return 0;
605}
606EXPORT_SYMBOL_GPL(l2tp_ioctl);
607
608static struct proto l2tp_ip_prot = {
609 .name = "L2TP/IP",
610 .owner = THIS_MODULE,
611 .init = l2tp_ip_open,
612 .close = l2tp_ip_close,
613 .bind = l2tp_ip_bind,
614 .connect = l2tp_ip_connect,
615 .disconnect = l2tp_ip_disconnect,
616 .ioctl = l2tp_ioctl,
617 .destroy = l2tp_ip_destroy_sock,
618 .setsockopt = ip_setsockopt,
619 .getsockopt = ip_getsockopt,
620 .sendmsg = l2tp_ip_sendmsg,
621 .recvmsg = l2tp_ip_recvmsg,
622 .backlog_rcv = l2tp_ip_backlog_recv,
623 .hash = l2tp_ip_hash,
624 .unhash = l2tp_ip_unhash,
625 .obj_size = sizeof(struct l2tp_ip_sock),
626};
627
628static const struct proto_ops l2tp_ip_ops = {
629 .family = PF_INET,
630 .owner = THIS_MODULE,
631 .release = inet_release,
632 .bind = inet_bind,
633 .connect = inet_dgram_connect,
634 .socketpair = sock_no_socketpair,
635 .accept = sock_no_accept,
636 .getname = l2tp_ip_getname,
637 .poll = datagram_poll,
638 .ioctl = inet_ioctl,
639 .gettstamp = sock_gettstamp,
640 .listen = sock_no_listen,
641 .shutdown = inet_shutdown,
642 .setsockopt = sock_common_setsockopt,
643 .getsockopt = sock_common_getsockopt,
644 .sendmsg = inet_sendmsg,
645 .recvmsg = sock_common_recvmsg,
646 .mmap = sock_no_mmap,
647};
648
649static struct inet_protosw l2tp_ip_protosw = {
650 .type = SOCK_DGRAM,
651 .protocol = IPPROTO_L2TP,
652 .prot = &l2tp_ip_prot,
653 .ops = &l2tp_ip_ops,
654};
655
656static struct net_protocol l2tp_ip_protocol __read_mostly = {
657 .handler = l2tp_ip_recv,
658};
659
660static __net_init int l2tp_ip_init_net(struct net *net)
661{
662 struct l2tp_ip_net *pn = net_generic(net, l2tp_ip_net_id);
663
664 rwlock_init(&pn->l2tp_ip_lock);
665 INIT_HLIST_HEAD(&pn->l2tp_ip_table);
666 INIT_HLIST_HEAD(&pn->l2tp_ip_bind_table);
667 return 0;
668}
669
670static __net_exit void l2tp_ip_exit_net(struct net *net)
671{
672 struct l2tp_ip_net *pn = l2tp_ip_pernet(net);
673
674 write_lock_bh(&pn->l2tp_ip_lock);
675 WARN_ON_ONCE(hlist_count_nodes(&pn->l2tp_ip_table) != 0);
676 WARN_ON_ONCE(hlist_count_nodes(&pn->l2tp_ip_bind_table) != 0);
677 write_unlock_bh(&pn->l2tp_ip_lock);
678}
679
680static struct pernet_operations l2tp_ip_net_ops = {
681 .init = l2tp_ip_init_net,
682 .exit = l2tp_ip_exit_net,
683 .id = &l2tp_ip_net_id,
684 .size = sizeof(struct l2tp_ip_net),
685};
686
687static int __init l2tp_ip_init(void)
688{
689 int err;
690
691 pr_info("L2TP IP encapsulation support (L2TPv3)\n");
692
693 err = register_pernet_device(&l2tp_ip_net_ops);
694 if (err)
695 goto out;
696
697 err = proto_register(&l2tp_ip_prot, 1);
698 if (err != 0)
699 goto out1;
700
701 err = inet_add_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
702 if (err)
703 goto out2;
704
705 inet_register_protosw(&l2tp_ip_protosw);
706 return 0;
707
708out2:
709 proto_unregister(&l2tp_ip_prot);
710out1:
711 unregister_pernet_device(&l2tp_ip_net_ops);
712out:
713 return err;
714}
715
716static void __exit l2tp_ip_exit(void)
717{
718 inet_unregister_protosw(&l2tp_ip_protosw);
719 inet_del_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
720 proto_unregister(&l2tp_ip_prot);
721 unregister_pernet_device(&l2tp_ip_net_ops);
722}
723
724module_init(l2tp_ip_init);
725module_exit(l2tp_ip_exit);
726
727MODULE_LICENSE("GPL");
728MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
729MODULE_DESCRIPTION("L2TP over IP");
730MODULE_VERSION("1.0");
731
732/* Use the values of SOCK_DGRAM (2) as type and IPPROTO_L2TP (115) as protocol,
733 * because __stringify doesn't like enums
734 */
735MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 115, 2);
736MODULE_ALIAS_NET_PF_PROTO(PF_INET, 115);