projects / linux-2.6-block.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
arp: filter NOARP neighbours for SIOCGARP
[linux-2.6-block.git] / net / l2tp / l2tp_ip6.c
CommitLineData
a32e0eec
CE		 1/*
2 * L2TPv3 IP encapsulation support for IPv6
3 *
4 * Copyright (c) 2012 Katalix Systems Ltd
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
a4ca44fa
JP		 12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
a32e0eec
CE		 14#include <linux/icmp.h>
15#include <linux/module.h>
16#include <linux/skbuff.h>
17#include <linux/random.h>
18#include <linux/socket.h>
19#include <linux/l2tp.h>
20#include <linux/in.h>
21#include <linux/in6.h>
22#include <net/sock.h>
23#include <net/ip.h>
24#include <net/icmp.h>
25#include <net/udp.h>
26#include <net/inet_common.h>
27#include <net/inet_hashtables.h>
28#include <net/tcp_states.h>
29#include <net/protocol.h>
30#include <net/xfrm.h>
31
32#include <net/transp_v6.h>
33#include <net/addrconf.h>
34#include <net/ip6_route.h>
35
36#include "l2tp_core.h"
37
38struct l2tp_ip6_sock {
39 /* inet_sock has to be the first member of l2tp_ip6_sock */
40 struct inet_sock inet;
41
42 u32 conn_id;
43 u32 peer_conn_id;
44
45 /* ipv6_pinfo has to be the last member of l2tp_ip6_sock, see
46 inet6_sk_generic */
47 struct ipv6_pinfo inet6;
48};
49
50static DEFINE_RWLOCK(l2tp_ip6_lock);
51static struct hlist_head l2tp_ip6_table;
52static struct hlist_head l2tp_ip6_bind_table;
53
54static inline struct l2tp_ip6_sock *l2tp_ip6_sk(const struct sock *sk)
55{
56 return (struct l2tp_ip6_sock *)sk;
57}
58
59static struct sock *__l2tp_ip6_bind_lookup(struct net *net,
60 struct in6_addr *laddr,
61 int dif, u32 tunnel_id)
62{
a32e0eec
CE		 63 struct sock *sk;
64
b67bfe0d 65 sk_for_each_bound(sk, &l2tp_ip6_bind_table) {
efe4208f 66 const struct in6_addr *addr = inet6_rcv_saddr(sk);
a32e0eec
CE		 67 struct l2tp_ip6_sock *l2tp = l2tp_ip6_sk(sk);
68
69 if (l2tp == NULL)
70 continue;
71
72 if ((l2tp->conn_id == tunnel_id) &&
73 net_eq(sock_net(sk), net) &&
74 !(addr && ipv6_addr_equal(addr, laddr)) &&
75 !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
76 goto found;
77 }
78
79 sk = NULL;
80found:
81 return sk;
82}
83
84static inline struct sock *l2tp_ip6_bind_lookup(struct net *net,
85 struct in6_addr *laddr,
86 int dif, u32 tunnel_id)
87{
88 struct sock *sk = __l2tp_ip6_bind_lookup(net, laddr, dif, tunnel_id);
89 if (sk)
90 sock_hold(sk);
91
92 return sk;
93}
94
95/* When processing receive frames, there are two cases to
96 * consider. Data frames consist of a non-zero session-id and an
97 * optional cookie. Control frames consist of a regular L2TP header
98 * preceded by 32-bits of zeros.
99 *
100 * L2TPv3 Session Header Over IP
101 *
102 * 0 1 2 3
103 * 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
104 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
105 * | Session ID |
106 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
107 * | Cookie (optional, maximum 64 bits)...
108 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
109 * |
110 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
111 *
112 * L2TPv3 Control Message Header Over IP
113 *
114 * 0 1 2 3
115 * 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
116 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
117 * | (32 bits of zeros) |
118 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
119 * |T|L|x|x|S|x|x|x|x|x|x|x| Ver | Length |
120 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
121 * | Control Connection ID |
122 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
123 * | Ns | Nr |
124 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
125 *
126 * All control frames are passed to userspace.
127 */
128static int l2tp_ip6_recv(struct sk_buff *skb)
129{
130 struct sock *sk;
131 u32 session_id;
132 u32 tunnel_id;
133 unsigned char *ptr, *optr;
134 struct l2tp_session *session;
135 struct l2tp_tunnel *tunnel = NULL;
136 int length;
a32e0eec
CE		 137
138 /* Point to L2TP header */
139 optr = ptr = skb->data;
140
141 if (!pskb_may_pull(skb, 4))
142 goto discard;
143
144 session_id = ntohl(*((__be32 *) ptr));
145 ptr += 4;
146
147 /* RFC3931: L2TP/IP packets have the first 4 bytes containing
148 * the session_id. If it is 0, the packet is a L2TP control
149 * frame and the session_id value can be discarded.
150 */
151 if (session_id == 0) {
152 __skb_pull(skb, 4);
153 goto pass_up;
154 }
155
156 /* Ok, this is a data packet. Lookup the session. */
157 session = l2tp_session_find(&init_net, NULL, session_id);
158 if (session == NULL)
159 goto discard;
160
161 tunnel = session->tunnel;
162 if (tunnel == NULL)
163 goto discard;
164
165 /* Trace packet contents, if enabled */
166 if (tunnel->debug & L2TP_MSG_DATA) {
167 length = min(32u, skb->len);
168 if (!pskb_may_pull(skb, length))
169 goto discard;
170
a4ca44fa
JP		 171 pr_debug("%s: ip recv\n", tunnel->name);
172 print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length);
a32e0eec
CE		 173 }
174
175 l2tp_recv_common(session, skb, ptr, optr, 0, skb->len,
176 tunnel->recv_payload_hook);
177 return 0;
178
179pass_up:
180 /* Get the tunnel_id from the L2TP header */
181 if (!pskb_may_pull(skb, 12))
182 goto discard;
183
184 if ((skb->data[0] & 0xc0) != 0xc0)
185 goto discard;
186
187 tunnel_id = ntohl(*(__be32 *) &skb->data[4]);
188 tunnel = l2tp_tunnel_find(&init_net, tunnel_id);
189 if (tunnel != NULL)
190 sk = tunnel->sock;
191 else {
192 struct ipv6hdr *iph = ipv6_hdr(skb);
193
194 read_lock_bh(&l2tp_ip6_lock);
195 sk = __l2tp_ip6_bind_lookup(&init_net, &iph->daddr,
196 0, tunnel_id);
197 read_unlock_bh(&l2tp_ip6_lock);
198 }
199
200 if (sk == NULL)
201 goto discard;
202
203 sock_hold(sk);
204
205 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
206 goto discard_put;
207
208 nf_reset(skb);
209
210 return sk_receive_skb(sk, skb, 1);
211
212discard_put:
213 sock_put(sk);
214
215discard:
216 kfree_skb(skb);
217 return 0;
218}
219
220static int l2tp_ip6_open(struct sock *sk)
221{
222 /* Prevent autobind. We don't have ports. */
223 inet_sk(sk)->inet_num = IPPROTO_L2TP;
224
225 write_lock_bh(&l2tp_ip6_lock);
226 sk_add_node(sk, &l2tp_ip6_table);
227 write_unlock_bh(&l2tp_ip6_lock);
228
229 return 0;
230}
231
232static void l2tp_ip6_close(struct sock *sk, long timeout)
233{
234 write_lock_bh(&l2tp_ip6_lock);
235 hlist_del_init(&sk->sk_bind_node);
236 sk_del_node_init(sk);
237 write_unlock_bh(&l2tp_ip6_lock);
238
239 sk_common_release(sk);
240}
241
242static void l2tp_ip6_destroy_sock(struct sock *sk)
243{
93606317
TP		 244 struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk);
245
a32e0eec
CE		 246 lock_sock(sk);
247 ip6_flush_pending_frames(sk);
248 release_sock(sk);
249
93606317
TP		 250 if (tunnel) {
251 l2tp_tunnel_closeall(tunnel);
252 sock_put(sk);
253 }
254
a32e0eec
CE		 255 inet6_destroy_sock(sk);
256}
257
258static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
259{
260 struct inet_sock *inet = inet_sk(sk);
261 struct ipv6_pinfo *np = inet6_sk(sk);
262 struct sockaddr_l2tpip6 *addr = (struct sockaddr_l2tpip6 *) uaddr;
263 __be32 v4addr = 0;
264 int addr_type;
265 int err;
266
c51ce497
JC		 267 if (!sock_flag(sk, SOCK_ZAPPED))
268 return -EINVAL;
269 if (addr->l2tp_family != AF_INET6)
270 return -EINVAL;
a32e0eec
CE		 271 if (addr_len < sizeof(*addr))
272 return -EINVAL;
273
274 addr_type = ipv6_addr_type(&addr->l2tp_addr);
275
276 /* l2tp_ip6 sockets are IPv6 only */
277 if (addr_type == IPV6_ADDR_MAPPED)
278 return -EADDRNOTAVAIL;
279
280 /* L2TP is point-point, not multicast */
281 if (addr_type & IPV6_ADDR_MULTICAST)
282 return -EADDRNOTAVAIL;
283
284 err = -EADDRINUSE;
285 read_lock_bh(&l2tp_ip6_lock);
286 if (__l2tp_ip6_bind_lookup(&init_net, &addr->l2tp_addr,
287 sk->sk_bound_dev_if, addr->l2tp_conn_id))
288 goto out_in_use;
289 read_unlock_bh(&l2tp_ip6_lock);
290
291 lock_sock(sk);
292
293 err = -EINVAL;
294 if (sk->sk_state != TCP_CLOSE)
295 goto out_unlock;
296
297 /* Check if the address belongs to the host. */
298 rcu_read_lock();
299 if (addr_type != IPV6_ADDR_ANY) {
300 struct net_device *dev = NULL;
301
302 if (addr_type & IPV6_ADDR_LINKLOCAL) {
303 if (addr_len >= sizeof(struct sockaddr_in6) &&
304 addr->l2tp_scope_id) {
305 /* Override any existing binding, if another
306 * one is supplied by user.
307 */
308 sk->sk_bound_dev_if = addr->l2tp_scope_id;
309 }
310
311 /* Binding to link-local address requires an
312 interface */
313 if (!sk->sk_bound_dev_if)
314 goto out_unlock_rcu;
315
316 err = -ENODEV;
317 dev = dev_get_by_index_rcu(sock_net(sk),
318 sk->sk_bound_dev_if);
319 if (!dev)
320 goto out_unlock_rcu;
321 }
322
323 /* ipv4 addr of the socket is invalid. Only the
324 * unspecified and mapped address have a v4 equivalent.
325 */
326 v4addr = LOOPBACK4_IPV6;
327 err = -EADDRNOTAVAIL;
328 if (!ipv6_chk_addr(sock_net(sk), &addr->l2tp_addr, dev, 0))
329 goto out_unlock_rcu;
330 }
331 rcu_read_unlock();
332
333 inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
efe4208f 334 sk->sk_v6_rcv_saddr = addr->l2tp_addr;
a32e0eec
CE		 335 np->saddr = addr->l2tp_addr;
336
337 l2tp_ip6_sk(sk)->conn_id = addr->l2tp_conn_id;
338
339 write_lock_bh(&l2tp_ip6_lock);
340 sk_add_bind_node(sk, &l2tp_ip6_bind_table);
341 sk_del_node_init(sk);
342 write_unlock_bh(&l2tp_ip6_lock);
343
c51ce497 344 sock_reset_flag(sk, SOCK_ZAPPED);
a32e0eec
CE		 345 release_sock(sk);
346 return 0;
347
348out_unlock_rcu:
349 rcu_read_unlock();
350out_unlock:
351 release_sock(sk);
352 return err;
353
354out_in_use:
355 read_unlock_bh(&l2tp_ip6_lock);
356 return err;
357}
358
359static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
360 int addr_len)
361{
362 struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *) uaddr;
363 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
364 struct in6_addr *daddr;
365 int addr_type;
366 int rc;
367
c51ce497
JC		 368 if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
369 return -EINVAL;
370
a32e0eec
CE		 371 if (addr_len < sizeof(*lsa))
372 return -EINVAL;
373
82b276cd
HFS		 374 if (usin->sin6_family != AF_INET6)
375 return -EINVAL;
376
a32e0eec
CE		 377 addr_type = ipv6_addr_type(&usin->sin6_addr);
378 if (addr_type & IPV6_ADDR_MULTICAST)
379 return -EINVAL;
380
381 if (addr_type & IPV6_ADDR_MAPPED) {
382 daddr = &usin->sin6_addr;
383 if (ipv4_is_multicast(daddr->s6_addr32[3]))
384 return -EINVAL;
385 }
386
387 rc = ip6_datagram_connect(sk, uaddr, addr_len);
388
389 lock_sock(sk);
390
391 l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
392
393 write_lock_bh(&l2tp_ip6_lock);
394 hlist_del_init(&sk->sk_bind_node);
395 sk_add_bind_node(sk, &l2tp_ip6_bind_table);
396 write_unlock_bh(&l2tp_ip6_lock);
397
398 release_sock(sk);
399
400 return rc;
401}
402
c51ce497
JC		 403static int l2tp_ip6_disconnect(struct sock *sk, int flags)
404{
405 if (sock_flag(sk, SOCK_ZAPPED))
406 return 0;
407
408 return udp_disconnect(sk, flags);
409}
410
a32e0eec
CE		 411static int l2tp_ip6_getname(struct socket *sock, struct sockaddr *uaddr,
412 int *uaddr_len, int peer)
413{
414 struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)uaddr;
415 struct sock *sk = sock->sk;
416 struct ipv6_pinfo *np = inet6_sk(sk);
417 struct l2tp_ip6_sock *lsk = l2tp_ip6_sk(sk);
418
419 lsa->l2tp_family = AF_INET6;
420 lsa->l2tp_flowinfo = 0;
421 lsa->l2tp_scope_id = 0;
04d4fbca 422 lsa->l2tp_unused = 0;
a32e0eec
CE		 423 if (peer) {
424 if (!lsk->peer_conn_id)
425 return -ENOTCONN;
426 lsa->l2tp_conn_id = lsk->peer_conn_id;
efe4208f 427 lsa->l2tp_addr = sk->sk_v6_daddr;
a32e0eec
CE		 428 if (np->sndflow)
429 lsa->l2tp_flowinfo = np->flow_label;
430 } else {
efe4208f 431 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
a32e0eec
CE		 432 lsa->l2tp_addr = np->saddr;
433 else
efe4208f 434 lsa->l2tp_addr = sk->sk_v6_rcv_saddr;
a32e0eec
CE		 435
436 lsa->l2tp_conn_id = lsk->conn_id;
437 }
438 if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
439 lsa->l2tp_scope_id = sk->sk_bound_dev_if;
440 *uaddr_len = sizeof(*lsa);
441 return 0;
442}
443
444static int l2tp_ip6_backlog_recv(struct sock *sk, struct sk_buff *skb)
445{
446 int rc;
447
448 /* Charge it to the socket, dropping if the queue is full. */
449 rc = sock_queue_rcv_skb(sk, skb);
450 if (rc < 0)
451 goto drop;
452
453 return 0;
454
455drop:
456 IP_INC_STATS(&init_net, IPSTATS_MIB_INDISCARDS);
457 kfree_skb(skb);
458 return -1;
459}
460
461static int l2tp_ip6_push_pending_frames(struct sock *sk)
462{
463 struct sk_buff *skb;
464 __be32 *transhdr = NULL;
465 int err = 0;
466
467 skb = skb_peek(&sk->sk_write_queue);
468 if (skb == NULL)
469 goto out;
470
471 transhdr = (__be32 *)skb_transport_header(skb);
472 *transhdr = 0;
473
474 err = ip6_push_pending_frames(sk);
475
476out:
477 return err;
478}
479
480/* Userspace will call sendmsg() on the tunnel socket to send L2TP
481 * control frames.
482 */
1b784140 483static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
a32e0eec
CE		 484{
485 struct ipv6_txoptions opt_space;
342dfc30 486 DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
a32e0eec
CE		 487 struct in6_addr *daddr, *final_p, final;
488 struct ipv6_pinfo *np = inet6_sk(sk);
489 struct ipv6_txoptions *opt = NULL;
490 struct ip6_flowlabel *flowlabel = NULL;
491 struct dst_entry *dst = NULL;
492 struct flowi6 fl6;
493 int addr_len = msg->msg_namelen;
494 int hlimit = -1;
495 int tclass = -1;
496 int dontfrag = -1;
497 int transhdrlen = 4; /* zero session-id */
498 int ulen = len + transhdrlen;
499 int err;
500
501 /* Rough check on arithmetic overflow,
502 better check is made in ip6_append_data().
503 */
504 if (len > INT_MAX)
505 return -EMSGSIZE;
506
507 /* Mirror BSD error message compatibility */
508 if (msg->msg_flags & MSG_OOB)
509 return -EOPNOTSUPP;
510
511 /*
512 * Get and verify the address.
513 */
514 memset(&fl6, 0, sizeof(fl6));
515
516 fl6.flowi6_mark = sk->sk_mark;
517
518 if (lsa) {
519 if (addr_len < SIN6_LEN_RFC2133)
520 return -EINVAL;
521
522 if (lsa->l2tp_family && lsa->l2tp_family != AF_INET6)
523 return -EAFNOSUPPORT;
524
525 daddr = &lsa->l2tp_addr;
526 if (np->sndflow) {
527 fl6.flowlabel = lsa->l2tp_flowinfo & IPV6_FLOWINFO_MASK;
528 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
529 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
530 if (flowlabel == NULL)
531 return -EINVAL;
a32e0eec
CE		 532 }
533 }
534
535 /*
536 * Otherwise it will be difficult to maintain
537 * sk->sk_dst_cache.
538 */
539 if (sk->sk_state == TCP_ESTABLISHED &&
efe4208f
ED		 540 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
541 daddr = &sk->sk_v6_daddr;
a32e0eec
CE		 542
543 if (addr_len >= sizeof(struct sockaddr_in6) &&
544 lsa->l2tp_scope_id &&
545 ipv6_addr_type(daddr) & IPV6_ADDR_LINKLOCAL)
546 fl6.flowi6_oif = lsa->l2tp_scope_id;
547 } else {
548 if (sk->sk_state != TCP_ESTABLISHED)
549 return -EDESTADDRREQ;
550
efe4208f 551 daddr = &sk->sk_v6_daddr;
a32e0eec
CE		 552 fl6.flowlabel = np->flow_label;
553 }
554
555 if (fl6.flowi6_oif == 0)
556 fl6.flowi6_oif = sk->sk_bound_dev_if;
557
558 if (msg->msg_controllen) {
559 opt = &opt_space;
560 memset(opt, 0, sizeof(struct ipv6_txoptions));
561 opt->tot_len = sizeof(struct ipv6_txoptions);
562
73df66f8
TP		 563 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
564 &hlimit, &tclass, &dontfrag);
a32e0eec
CE		 565 if (err < 0) {
566 fl6_sock_release(flowlabel);
567 return err;
568 }
569 if ((fl6.flowlabel & IPV6_FLOWLABEL_MASK) && !flowlabel) {
570 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
571 if (flowlabel == NULL)
572 return -EINVAL;
573 }
574 if (!(opt->opt_nflen|opt->opt_flen))
575 opt = NULL;
576 }
577
578 if (opt == NULL)
579 opt = np->opt;
580 if (flowlabel)
581 opt = fl6_merge_options(&opt_space, flowlabel, opt);
582 opt = ipv6_fixup_options(&opt_space, opt);
583
584 fl6.flowi6_proto = sk->sk_protocol;
585 if (!ipv6_addr_any(daddr))
586 fl6.daddr = *daddr;
587 else
588 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
589 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
590 fl6.saddr = np->saddr;
591
592 final_p = fl6_update_dst(&fl6, opt, &final);
593
594 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
595 fl6.flowi6_oif = np->mcast_oif;
596 else if (!fl6.flowi6_oif)
597 fl6.flowi6_oif = np->ucast_oif;
598
599 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
600
0e0d44ab 601 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
a32e0eec
CE		 602 if (IS_ERR(dst)) {
603 err = PTR_ERR(dst);
604 goto out;
605 }
606
5c98631c
LC		 607 if (hlimit < 0)
608 hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
a32e0eec
CE		 609
610 if (tclass < 0)
611 tclass = np->tclass;
612
613 if (dontfrag < 0)
614 dontfrag = np->dontfrag;
615
616 if (msg->msg_flags & MSG_CONFIRM)
617 goto do_confirm;
618
619back_from_confirm:
620 lock_sock(sk);
f69e6d13 621 err = ip6_append_data(sk, ip_generic_getfrag, msg,
a32e0eec
CE		 622 ulen, transhdrlen, hlimit, tclass, opt,
623 &fl6, (struct rt6_info *)dst,
624 msg->msg_flags, dontfrag);
625 if (err)
626 ip6_flush_pending_frames(sk);
627 else if (!(msg->msg_flags & MSG_MORE))
628 err = l2tp_ip6_push_pending_frames(sk);
629 release_sock(sk);
630done:
631 dst_release(dst);
632out:
633 fl6_sock_release(flowlabel);
634
635 return err < 0 ? err : len;
636
637do_confirm:
638 dst_confirm(dst);
639 if (!(msg->msg_flags & MSG_PROBE) || len)
640 goto back_from_confirm;
641 err = 0;
642 goto done;
643}
644
1b784140
YX		 645static int l2tp_ip6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
646 int noblock, int flags, int *addr_len)
a32e0eec 647{
700163db 648 struct ipv6_pinfo *np = inet6_sk(sk);
342dfc30 649 DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
a32e0eec
CE		 650 size_t copied = 0;
651 int err = -EOPNOTSUPP;
652 struct sk_buff *skb;
653
654 if (flags & MSG_OOB)
655 goto out;
656
657 if (addr_len)
658 *addr_len = sizeof(*lsa);
659
660 if (flags & MSG_ERRQUEUE)
85fbaa75 661 return ipv6_recv_error(sk, msg, len, addr_len);
a32e0eec
CE		 662
663 skb = skb_recv_datagram(sk, flags, noblock, &err);
664 if (!skb)
665 goto out;
666
667 copied = skb->len;
668 if (len < copied) {
669 msg->msg_flags |= MSG_TRUNC;
670 copied = len;
671 }
672
51f3d02b 673 err = skb_copy_datagram_msg(skb, 0, msg, copied);
a32e0eec
CE		 674 if (err)
675 goto done;
676
677 sock_recv_timestamp(msg, sk, skb);
678
679 /* Copy the address. */
680 if (lsa) {
681 lsa->l2tp_family = AF_INET6;
682 lsa->l2tp_unused = 0;
683 lsa->l2tp_addr = ipv6_hdr(skb)->saddr;
684 lsa->l2tp_flowinfo = 0;
685 lsa->l2tp_scope_id = 0;
b860d3cc 686 lsa->l2tp_conn_id = 0;
a32e0eec 687 if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
4330487a 688 lsa->l2tp_scope_id = inet6_iif(skb);
a32e0eec
CE		 689 }
690
700163db
TP		 691 if (np->rxopt.all)
692 ip6_datagram_recv_ctl(sk, msg, skb);
a32e0eec
CE		 693
694 if (flags & MSG_TRUNC)
695 copied = skb->len;
696done:
697 skb_free_datagram(sk, skb);
698out:
699 return err ? err : copied;
700}
701
702static struct proto l2tp_ip6_prot = {
703 .name = "L2TP/IPv6",
704 .owner = THIS_MODULE,
705 .init = l2tp_ip6_open,
706 .close = l2tp_ip6_close,
707 .bind = l2tp_ip6_bind,
708 .connect = l2tp_ip6_connect,
c51ce497 709 .disconnect = l2tp_ip6_disconnect,
a32e0eec
CE		 710 .ioctl = udp_ioctl,
711 .destroy = l2tp_ip6_destroy_sock,
712 .setsockopt = ipv6_setsockopt,
713 .getsockopt = ipv6_getsockopt,
714 .sendmsg = l2tp_ip6_sendmsg,
715 .recvmsg = l2tp_ip6_recvmsg,
716 .backlog_rcv = l2tp_ip6_backlog_recv,
717 .hash = inet_hash,
718 .unhash = inet_unhash,
719 .obj_size = sizeof(struct l2tp_ip6_sock),
720#ifdef CONFIG_COMPAT
721 .compat_setsockopt = compat_ipv6_setsockopt,
722 .compat_getsockopt = compat_ipv6_getsockopt,
723#endif
724};
725
726static const struct proto_ops l2tp_ip6_ops = {
727 .family = PF_INET6,
728 .owner = THIS_MODULE,
729 .release = inet6_release,
730 .bind = inet6_bind,
731 .connect = inet_dgram_connect,
732 .socketpair = sock_no_socketpair,
733 .accept = sock_no_accept,
734 .getname = l2tp_ip6_getname,
735 .poll = datagram_poll,
736 .ioctl = inet6_ioctl,
737 .listen = sock_no_listen,
738 .shutdown = inet_shutdown,
739 .setsockopt = sock_common_setsockopt,
740 .getsockopt = sock_common_getsockopt,
741 .sendmsg = inet_sendmsg,
742 .recvmsg = sock_common_recvmsg,
743 .mmap = sock_no_mmap,
744 .sendpage = sock_no_sendpage,
745#ifdef CONFIG_COMPAT
746 .compat_setsockopt = compat_sock_common_setsockopt,
747 .compat_getsockopt = compat_sock_common_getsockopt,
748#endif
749};
750
751static struct inet_protosw l2tp_ip6_protosw = {
752 .type = SOCK_DGRAM,
753 .protocol = IPPROTO_L2TP,
754 .prot = &l2tp_ip6_prot,
755 .ops = &l2tp_ip6_ops,
a32e0eec
CE		 756};
757
758static struct inet6_protocol l2tp_ip6_protocol __read_mostly = {
759 .handler = l2tp_ip6_recv,
760};
761
762static int __init l2tp_ip6_init(void)
763{
764 int err;
765
a4ca44fa 766 pr_info("L2TP IP encapsulation support for IPv6 (L2TPv3)\n");
a32e0eec
CE		 767
768 err = proto_register(&l2tp_ip6_prot, 1);
769 if (err != 0)
770 goto out;
771
772 err = inet6_add_protocol(&l2tp_ip6_protocol, IPPROTO_L2TP);
773 if (err)
774 goto out1;
775
776 inet6_register_protosw(&l2tp_ip6_protosw);
777 return 0;
778
779out1:
780 proto_unregister(&l2tp_ip6_prot);
781out:
782 return err;
783}
784
785static void __exit l2tp_ip6_exit(void)
786{
787 inet6_unregister_protosw(&l2tp_ip6_protosw);
788 inet6_del_protocol(&l2tp_ip6_protocol, IPPROTO_L2TP);
789 proto_unregister(&l2tp_ip6_prot);
790}
791
792module_init(l2tp_ip6_init);
793module_exit(l2tp_ip6_exit);
794
795MODULE_LICENSE("GPL");
796MODULE_AUTHOR("Chris Elston <celston@katalix.com>");
797MODULE_DESCRIPTION("L2TP IP encapsulation for IPv6");
798MODULE_VERSION("1.0");
799
800/* Use the value of SOCK_DGRAM (2) directory, because __stringify doesn't like
801 * enums
802 */
803MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 2, IPPROTO_L2TP);
Linux 6.x block layer and io_uring tree(s)