Commit | Line | Data |
---|---|---|
0d76751f JC |
1 | /* |
2 | * L2TPv3 IP encapsulation support | |
3 | * | |
4 | * Copyright (c) 2008,2009,2010 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 | ||
0d76751f JC |
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 <net/sock.h> | |
22 | #include <net/ip.h> | |
23 | #include <net/icmp.h> | |
24 | #include <net/udp.h> | |
25 | #include <net/inet_common.h> | |
26 | #include <net/inet_hashtables.h> | |
27 | #include <net/tcp_states.h> | |
28 | #include <net/protocol.h> | |
29 | #include <net/xfrm.h> | |
30 | ||
31 | #include "l2tp_core.h" | |
32 | ||
33 | struct l2tp_ip_sock { | |
34 | /* inet_sock has to be the first member of l2tp_ip_sock */ | |
35 | struct inet_sock inet; | |
36 | ||
c8657fd5 JC |
37 | u32 conn_id; |
38 | u32 peer_conn_id; | |
0d76751f JC |
39 | }; |
40 | ||
41 | static DEFINE_RWLOCK(l2tp_ip_lock); | |
42 | static struct hlist_head l2tp_ip_table; | |
43 | static struct hlist_head l2tp_ip_bind_table; | |
44 | ||
45 | static inline struct l2tp_ip_sock *l2tp_ip_sk(const struct sock *sk) | |
46 | { | |
47 | return (struct l2tp_ip_sock *)sk; | |
48 | } | |
49 | ||
50 | static struct sock *__l2tp_ip_bind_lookup(struct net *net, __be32 laddr, int dif, u32 tunnel_id) | |
51 | { | |
52 | struct hlist_node *node; | |
53 | struct sock *sk; | |
54 | ||
55 | sk_for_each_bound(sk, node, &l2tp_ip_bind_table) { | |
56 | struct inet_sock *inet = inet_sk(sk); | |
57 | struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk); | |
58 | ||
59 | if (l2tp == NULL) | |
60 | continue; | |
61 | ||
62 | if ((l2tp->conn_id == tunnel_id) && | |
e83726b0 | 63 | net_eq(sock_net(sk), net) && |
0d76751f JC |
64 | !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) && |
65 | !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)) | |
66 | goto found; | |
67 | } | |
68 | ||
69 | sk = NULL; | |
70 | found: | |
71 | return sk; | |
72 | } | |
73 | ||
74 | static inline struct sock *l2tp_ip_bind_lookup(struct net *net, __be32 laddr, int dif, u32 tunnel_id) | |
75 | { | |
76 | struct sock *sk = __l2tp_ip_bind_lookup(net, laddr, dif, tunnel_id); | |
77 | if (sk) | |
78 | sock_hold(sk); | |
79 | ||
80 | return sk; | |
81 | } | |
82 | ||
83 | /* When processing receive frames, there are two cases to | |
84 | * consider. Data frames consist of a non-zero session-id and an | |
85 | * optional cookie. Control frames consist of a regular L2TP header | |
86 | * preceded by 32-bits of zeros. | |
87 | * | |
88 | * L2TPv3 Session Header Over IP | |
89 | * | |
90 | * 0 1 2 3 | |
91 | * 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 | |
92 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
93 | * | Session ID | | |
94 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
95 | * | Cookie (optional, maximum 64 bits)... | |
96 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
97 | * | | |
98 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
99 | * | |
100 | * L2TPv3 Control Message 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 | * | (32 bits of zeros) | | |
106 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
107 | * |T|L|x|x|S|x|x|x|x|x|x|x| Ver | Length | | |
108 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
109 | * | Control Connection ID | | |
110 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
111 | * | Ns | Nr | | |
112 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
113 | * | |
114 | * All control frames are passed to userspace. | |
115 | */ | |
116 | static int l2tp_ip_recv(struct sk_buff *skb) | |
117 | { | |
9d6ddb19 | 118 | struct net *net = dev_net(skb->dev); |
0d76751f JC |
119 | struct sock *sk; |
120 | u32 session_id; | |
121 | u32 tunnel_id; | |
122 | unsigned char *ptr, *optr; | |
123 | struct l2tp_session *session; | |
124 | struct l2tp_tunnel *tunnel = NULL; | |
125 | int length; | |
0d76751f JC |
126 | |
127 | /* Point to L2TP header */ | |
128 | optr = ptr = skb->data; | |
129 | ||
130 | if (!pskb_may_pull(skb, 4)) | |
131 | goto discard; | |
132 | ||
133 | session_id = ntohl(*((__be32 *) ptr)); | |
134 | ptr += 4; | |
135 | ||
136 | /* RFC3931: L2TP/IP packets have the first 4 bytes containing | |
137 | * the session_id. If it is 0, the packet is a L2TP control | |
138 | * frame and the session_id value can be discarded. | |
139 | */ | |
140 | if (session_id == 0) { | |
141 | __skb_pull(skb, 4); | |
142 | goto pass_up; | |
143 | } | |
144 | ||
145 | /* Ok, this is a data packet. Lookup the session. */ | |
9d6ddb19 | 146 | session = l2tp_session_find(net, NULL, session_id); |
0d76751f JC |
147 | if (session == NULL) |
148 | goto discard; | |
149 | ||
150 | tunnel = session->tunnel; | |
151 | if (tunnel == NULL) | |
152 | goto discard; | |
153 | ||
154 | /* Trace packet contents, if enabled */ | |
155 | if (tunnel->debug & L2TP_MSG_DATA) { | |
156 | length = min(32u, skb->len); | |
157 | if (!pskb_may_pull(skb, length)) | |
158 | goto discard; | |
159 | ||
a4ca44fa JP |
160 | pr_debug("%s: ip recv\n", tunnel->name); |
161 | print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length); | |
0d76751f JC |
162 | } |
163 | ||
164 | l2tp_recv_common(session, skb, ptr, optr, 0, skb->len, tunnel->recv_payload_hook); | |
165 | ||
166 | return 0; | |
167 | ||
168 | pass_up: | |
169 | /* Get the tunnel_id from the L2TP header */ | |
170 | if (!pskb_may_pull(skb, 12)) | |
171 | goto discard; | |
172 | ||
173 | if ((skb->data[0] & 0xc0) != 0xc0) | |
174 | goto discard; | |
175 | ||
176 | tunnel_id = ntohl(*(__be32 *) &skb->data[4]); | |
9d6ddb19 | 177 | tunnel = l2tp_tunnel_find(net, tunnel_id); |
0d76751f JC |
178 | if (tunnel != NULL) |
179 | sk = tunnel->sock; | |
180 | else { | |
181 | struct iphdr *iph = (struct iphdr *) skb_network_header(skb); | |
182 | ||
183 | read_lock_bh(&l2tp_ip_lock); | |
9d6ddb19 | 184 | sk = __l2tp_ip_bind_lookup(net, iph->daddr, 0, tunnel_id); |
0d76751f JC |
185 | read_unlock_bh(&l2tp_ip_lock); |
186 | } | |
187 | ||
188 | if (sk == NULL) | |
189 | goto discard; | |
190 | ||
191 | sock_hold(sk); | |
192 | ||
193 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) | |
194 | goto discard_put; | |
195 | ||
196 | nf_reset(skb); | |
197 | ||
198 | return sk_receive_skb(sk, skb, 1); | |
199 | ||
200 | discard_put: | |
201 | sock_put(sk); | |
202 | ||
203 | discard: | |
204 | kfree_skb(skb); | |
205 | return 0; | |
206 | } | |
207 | ||
208 | static int l2tp_ip_open(struct sock *sk) | |
209 | { | |
210 | /* Prevent autobind. We don't have ports. */ | |
211 | inet_sk(sk)->inet_num = IPPROTO_L2TP; | |
212 | ||
213 | write_lock_bh(&l2tp_ip_lock); | |
214 | sk_add_node(sk, &l2tp_ip_table); | |
215 | write_unlock_bh(&l2tp_ip_lock); | |
216 | ||
217 | return 0; | |
218 | } | |
219 | ||
220 | static void l2tp_ip_close(struct sock *sk, long timeout) | |
221 | { | |
222 | write_lock_bh(&l2tp_ip_lock); | |
223 | hlist_del_init(&sk->sk_bind_node); | |
d1f224ae | 224 | sk_del_node_init(sk); |
0d76751f JC |
225 | write_unlock_bh(&l2tp_ip_lock); |
226 | sk_common_release(sk); | |
227 | } | |
228 | ||
229 | static void l2tp_ip_destroy_sock(struct sock *sk) | |
230 | { | |
231 | struct sk_buff *skb; | |
232 | ||
233 | while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) | |
234 | kfree_skb(skb); | |
235 | ||
236 | sk_refcnt_debug_dec(sk); | |
237 | } | |
238 | ||
239 | static int l2tp_ip_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
240 | { | |
241 | struct inet_sock *inet = inet_sk(sk); | |
242 | struct sockaddr_l2tpip *addr = (struct sockaddr_l2tpip *) uaddr; | |
9d6ddb19 | 243 | struct net *net = sock_net(sk); |
c51ce497 | 244 | int ret; |
0d76751f JC |
245 | int chk_addr_ret; |
246 | ||
c51ce497 JC |
247 | if (!sock_flag(sk, SOCK_ZAPPED)) |
248 | return -EINVAL; | |
249 | if (addr_len < sizeof(struct sockaddr_l2tpip)) | |
250 | return -EINVAL; | |
251 | if (addr->l2tp_family != AF_INET) | |
252 | return -EINVAL; | |
253 | ||
0d76751f JC |
254 | ret = -EADDRINUSE; |
255 | read_lock_bh(&l2tp_ip_lock); | |
9d6ddb19 DM |
256 | if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr, |
257 | sk->sk_bound_dev_if, addr->l2tp_conn_id)) | |
0d76751f JC |
258 | goto out_in_use; |
259 | ||
260 | read_unlock_bh(&l2tp_ip_lock); | |
261 | ||
262 | lock_sock(sk); | |
263 | if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_l2tpip)) | |
264 | goto out; | |
265 | ||
9d6ddb19 | 266 | chk_addr_ret = inet_addr_type(net, addr->l2tp_addr.s_addr); |
0d76751f JC |
267 | ret = -EADDRNOTAVAIL; |
268 | if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL && | |
269 | chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST) | |
270 | goto out; | |
271 | ||
c9be48dc JC |
272 | if (addr->l2tp_addr.s_addr) |
273 | inet->inet_rcv_saddr = inet->inet_saddr = addr->l2tp_addr.s_addr; | |
0d76751f JC |
274 | if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) |
275 | inet->inet_saddr = 0; /* Use device */ | |
276 | sk_dst_reset(sk); | |
277 | ||
278 | l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id; | |
279 | ||
280 | write_lock_bh(&l2tp_ip_lock); | |
281 | sk_add_bind_node(sk, &l2tp_ip_bind_table); | |
282 | sk_del_node_init(sk); | |
283 | write_unlock_bh(&l2tp_ip_lock); | |
284 | ret = 0; | |
c51ce497 JC |
285 | sock_reset_flag(sk, SOCK_ZAPPED); |
286 | ||
0d76751f JC |
287 | out: |
288 | release_sock(sk); | |
289 | ||
290 | return ret; | |
291 | ||
292 | out_in_use: | |
293 | read_unlock_bh(&l2tp_ip_lock); | |
294 | ||
295 | return ret; | |
296 | } | |
297 | ||
298 | static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
299 | { | |
0d76751f | 300 | struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *) uaddr; |
de3c7a18 | 301 | int rc; |
0d76751f | 302 | |
c51ce497 JC |
303 | if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */ |
304 | return -EINVAL; | |
305 | ||
0d76751f | 306 | if (addr_len < sizeof(*lsa)) |
de3c7a18 | 307 | return -EINVAL; |
2f16270f | 308 | |
0d76751f | 309 | if (ipv4_is_multicast(lsa->l2tp_addr.s_addr)) |
de3c7a18 | 310 | return -EINVAL; |
0d76751f | 311 | |
de3c7a18 JC |
312 | rc = ip4_datagram_connect(sk, uaddr, addr_len); |
313 | if (rc < 0) | |
314 | return rc; | |
0d76751f | 315 | |
de3c7a18 | 316 | lock_sock(sk); |
0d76751f JC |
317 | |
318 | l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id; | |
319 | ||
0d76751f JC |
320 | write_lock_bh(&l2tp_ip_lock); |
321 | hlist_del_init(&sk->sk_bind_node); | |
322 | sk_add_bind_node(sk, &l2tp_ip_bind_table); | |
323 | write_unlock_bh(&l2tp_ip_lock); | |
324 | ||
2f16270f | 325 | release_sock(sk); |
0d76751f JC |
326 | return rc; |
327 | } | |
328 | ||
c51ce497 JC |
329 | static int l2tp_ip_disconnect(struct sock *sk, int flags) |
330 | { | |
331 | if (sock_flag(sk, SOCK_ZAPPED)) | |
332 | return 0; | |
333 | ||
334 | return udp_disconnect(sk, flags); | |
335 | } | |
336 | ||
0d76751f JC |
337 | static int l2tp_ip_getname(struct socket *sock, struct sockaddr *uaddr, |
338 | int *uaddr_len, int peer) | |
339 | { | |
340 | struct sock *sk = sock->sk; | |
341 | struct inet_sock *inet = inet_sk(sk); | |
342 | struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk); | |
343 | struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr; | |
344 | ||
345 | memset(lsa, 0, sizeof(*lsa)); | |
346 | lsa->l2tp_family = AF_INET; | |
347 | if (peer) { | |
348 | if (!inet->inet_dport) | |
349 | return -ENOTCONN; | |
350 | lsa->l2tp_conn_id = lsk->peer_conn_id; | |
351 | lsa->l2tp_addr.s_addr = inet->inet_daddr; | |
352 | } else { | |
353 | __be32 addr = inet->inet_rcv_saddr; | |
354 | if (!addr) | |
355 | addr = inet->inet_saddr; | |
356 | lsa->l2tp_conn_id = lsk->conn_id; | |
357 | lsa->l2tp_addr.s_addr = addr; | |
358 | } | |
359 | *uaddr_len = sizeof(*lsa); | |
360 | return 0; | |
361 | } | |
362 | ||
363 | static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb) | |
364 | { | |
365 | int rc; | |
366 | ||
0d76751f JC |
367 | /* Charge it to the socket, dropping if the queue is full. */ |
368 | rc = sock_queue_rcv_skb(sk, skb); | |
369 | if (rc < 0) | |
370 | goto drop; | |
371 | ||
372 | return 0; | |
373 | ||
374 | drop: | |
9d6ddb19 | 375 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS); |
0d76751f JC |
376 | kfree_skb(skb); |
377 | return -1; | |
378 | } | |
379 | ||
380 | /* Userspace will call sendmsg() on the tunnel socket to send L2TP | |
381 | * control frames. | |
382 | */ | |
383 | static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len) | |
384 | { | |
385 | struct sk_buff *skb; | |
386 | int rc; | |
0d76751f | 387 | struct inet_sock *inet = inet_sk(sk); |
0d76751f | 388 | struct rtable *rt = NULL; |
fdbb0f07 | 389 | struct flowi4 *fl4; |
0d76751f JC |
390 | int connected = 0; |
391 | __be32 daddr; | |
392 | ||
2f16270f DM |
393 | lock_sock(sk); |
394 | ||
395 | rc = -ENOTCONN; | |
0d76751f | 396 | if (sock_flag(sk, SOCK_DEAD)) |
2f16270f | 397 | goto out; |
0d76751f JC |
398 | |
399 | /* Get and verify the address. */ | |
400 | if (msg->msg_name) { | |
401 | struct sockaddr_l2tpip *lip = (struct sockaddr_l2tpip *) msg->msg_name; | |
2f16270f | 402 | rc = -EINVAL; |
0d76751f | 403 | if (msg->msg_namelen < sizeof(*lip)) |
2f16270f | 404 | goto out; |
0d76751f JC |
405 | |
406 | if (lip->l2tp_family != AF_INET) { | |
2f16270f | 407 | rc = -EAFNOSUPPORT; |
0d76751f | 408 | if (lip->l2tp_family != AF_UNSPEC) |
2f16270f | 409 | goto out; |
0d76751f JC |
410 | } |
411 | ||
412 | daddr = lip->l2tp_addr.s_addr; | |
413 | } else { | |
84768edb | 414 | rc = -EDESTADDRREQ; |
0d76751f | 415 | if (sk->sk_state != TCP_ESTABLISHED) |
84768edb | 416 | goto out; |
0d76751f JC |
417 | |
418 | daddr = inet->inet_daddr; | |
419 | connected = 1; | |
420 | } | |
421 | ||
422 | /* Allocate a socket buffer */ | |
423 | rc = -ENOMEM; | |
424 | skb = sock_wmalloc(sk, 2 + NET_SKB_PAD + sizeof(struct iphdr) + | |
425 | 4 + len, 0, GFP_KERNEL); | |
426 | if (!skb) | |
427 | goto error; | |
428 | ||
429 | /* Reserve space for headers, putting IP header on 4-byte boundary. */ | |
430 | skb_reserve(skb, 2 + NET_SKB_PAD); | |
431 | skb_reset_network_header(skb); | |
432 | skb_reserve(skb, sizeof(struct iphdr)); | |
433 | skb_reset_transport_header(skb); | |
434 | ||
435 | /* Insert 0 session_id */ | |
436 | *((__be32 *) skb_put(skb, 4)) = 0; | |
437 | ||
438 | /* Copy user data into skb */ | |
439 | rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); | |
440 | if (rc < 0) { | |
441 | kfree_skb(skb); | |
442 | goto error; | |
443 | } | |
444 | ||
fdbb0f07 | 445 | fl4 = &inet->cork.fl.u.ip4; |
0d76751f JC |
446 | if (connected) |
447 | rt = (struct rtable *) __sk_dst_check(sk, 0); | |
448 | ||
081b1b1b | 449 | rcu_read_lock(); |
0d76751f | 450 | if (rt == NULL) { |
081b1b1b | 451 | const struct ip_options_rcu *inet_opt; |
f6d8bd05 | 452 | |
778865a5 | 453 | inet_opt = rcu_dereference(inet->inet_opt); |
f6d8bd05 | 454 | |
0d76751f | 455 | /* Use correct destination address if we have options. */ |
f6d8bd05 ED |
456 | if (inet_opt && inet_opt->opt.srr) |
457 | daddr = inet_opt->opt.faddr; | |
0d76751f | 458 | |
78fbfd8a DM |
459 | /* If this fails, retransmit mechanism of transport layer will |
460 | * keep trying until route appears or the connection times | |
461 | * itself out. | |
462 | */ | |
fdbb0f07 | 463 | rt = ip_route_output_ports(sock_net(sk), fl4, sk, |
78fbfd8a DM |
464 | daddr, inet->inet_saddr, |
465 | inet->inet_dport, inet->inet_sport, | |
466 | sk->sk_protocol, RT_CONN_FLAGS(sk), | |
467 | sk->sk_bound_dev_if); | |
468 | if (IS_ERR(rt)) | |
469 | goto no_route; | |
4399a4df | 470 | if (connected) { |
081b1b1b | 471 | sk_setup_caps(sk, &rt->dst); |
4399a4df ED |
472 | } else { |
473 | skb_dst_set(skb, &rt->dst); | |
474 | goto xmit; | |
475 | } | |
0d76751f | 476 | } |
081b1b1b ED |
477 | |
478 | /* We dont need to clone dst here, it is guaranteed to not disappear. | |
479 | * __dev_xmit_skb() might force a refcount if needed. | |
480 | */ | |
481 | skb_dst_set_noref(skb, &rt->dst); | |
0d76751f | 482 | |
4399a4df | 483 | xmit: |
0d76751f | 484 | /* Queue the packet to IP for output */ |
d9d8da80 | 485 | rc = ip_queue_xmit(skb, &inet->cork.fl); |
081b1b1b | 486 | rcu_read_unlock(); |
0d76751f JC |
487 | |
488 | error: | |
c8657fd5 | 489 | if (rc >= 0) |
0d76751f | 490 | rc = len; |
0d76751f | 491 | |
2f16270f DM |
492 | out: |
493 | release_sock(sk); | |
0d76751f JC |
494 | return rc; |
495 | ||
496 | no_route: | |
081b1b1b | 497 | rcu_read_unlock(); |
0d76751f JC |
498 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
499 | kfree_skb(skb); | |
2f16270f DM |
500 | rc = -EHOSTUNREACH; |
501 | goto out; | |
0d76751f JC |
502 | } |
503 | ||
504 | static int l2tp_ip_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, | |
505 | size_t len, int noblock, int flags, int *addr_len) | |
506 | { | |
507 | struct inet_sock *inet = inet_sk(sk); | |
0d76751f JC |
508 | size_t copied = 0; |
509 | int err = -EOPNOTSUPP; | |
510 | struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; | |
511 | struct sk_buff *skb; | |
512 | ||
513 | if (flags & MSG_OOB) | |
514 | goto out; | |
515 | ||
516 | if (addr_len) | |
517 | *addr_len = sizeof(*sin); | |
518 | ||
519 | skb = skb_recv_datagram(sk, flags, noblock, &err); | |
520 | if (!skb) | |
521 | goto out; | |
522 | ||
523 | copied = skb->len; | |
524 | if (len < copied) { | |
525 | msg->msg_flags |= MSG_TRUNC; | |
526 | copied = len; | |
527 | } | |
528 | ||
529 | err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); | |
530 | if (err) | |
531 | goto done; | |
532 | ||
533 | sock_recv_timestamp(msg, sk, skb); | |
534 | ||
535 | /* Copy the address. */ | |
536 | if (sin) { | |
537 | sin->sin_family = AF_INET; | |
538 | sin->sin_addr.s_addr = ip_hdr(skb)->saddr; | |
539 | sin->sin_port = 0; | |
540 | memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); | |
541 | } | |
542 | if (inet->cmsg_flags) | |
543 | ip_cmsg_recv(msg, skb); | |
544 | if (flags & MSG_TRUNC) | |
545 | copied = skb->len; | |
546 | done: | |
547 | skb_free_datagram(sk, skb); | |
548 | out: | |
c8657fd5 | 549 | return err ? err : copied; |
0d76751f JC |
550 | } |
551 | ||
fc130840 | 552 | static struct proto l2tp_ip_prot = { |
0d76751f JC |
553 | .name = "L2TP/IP", |
554 | .owner = THIS_MODULE, | |
555 | .init = l2tp_ip_open, | |
556 | .close = l2tp_ip_close, | |
557 | .bind = l2tp_ip_bind, | |
558 | .connect = l2tp_ip_connect, | |
c51ce497 | 559 | .disconnect = l2tp_ip_disconnect, |
0d76751f JC |
560 | .ioctl = udp_ioctl, |
561 | .destroy = l2tp_ip_destroy_sock, | |
562 | .setsockopt = ip_setsockopt, | |
563 | .getsockopt = ip_getsockopt, | |
564 | .sendmsg = l2tp_ip_sendmsg, | |
565 | .recvmsg = l2tp_ip_recvmsg, | |
566 | .backlog_rcv = l2tp_ip_backlog_recv, | |
567 | .hash = inet_hash, | |
568 | .unhash = inet_unhash, | |
569 | .obj_size = sizeof(struct l2tp_ip_sock), | |
570 | #ifdef CONFIG_COMPAT | |
571 | .compat_setsockopt = compat_ip_setsockopt, | |
572 | .compat_getsockopt = compat_ip_getsockopt, | |
573 | #endif | |
574 | }; | |
575 | ||
576 | static const struct proto_ops l2tp_ip_ops = { | |
577 | .family = PF_INET, | |
578 | .owner = THIS_MODULE, | |
579 | .release = inet_release, | |
580 | .bind = inet_bind, | |
581 | .connect = inet_dgram_connect, | |
582 | .socketpair = sock_no_socketpair, | |
583 | .accept = sock_no_accept, | |
584 | .getname = l2tp_ip_getname, | |
585 | .poll = datagram_poll, | |
586 | .ioctl = inet_ioctl, | |
587 | .listen = sock_no_listen, | |
588 | .shutdown = inet_shutdown, | |
589 | .setsockopt = sock_common_setsockopt, | |
590 | .getsockopt = sock_common_getsockopt, | |
591 | .sendmsg = inet_sendmsg, | |
592 | .recvmsg = sock_common_recvmsg, | |
593 | .mmap = sock_no_mmap, | |
594 | .sendpage = sock_no_sendpage, | |
595 | #ifdef CONFIG_COMPAT | |
596 | .compat_setsockopt = compat_sock_common_setsockopt, | |
597 | .compat_getsockopt = compat_sock_common_getsockopt, | |
598 | #endif | |
599 | }; | |
600 | ||
601 | static struct inet_protosw l2tp_ip_protosw = { | |
602 | .type = SOCK_DGRAM, | |
603 | .protocol = IPPROTO_L2TP, | |
604 | .prot = &l2tp_ip_prot, | |
605 | .ops = &l2tp_ip_ops, | |
606 | .no_check = 0, | |
607 | }; | |
608 | ||
609 | static struct net_protocol l2tp_ip_protocol __read_mostly = { | |
610 | .handler = l2tp_ip_recv, | |
9d6ddb19 | 611 | .netns_ok = 1, |
0d76751f JC |
612 | }; |
613 | ||
614 | static int __init l2tp_ip_init(void) | |
615 | { | |
616 | int err; | |
617 | ||
a4ca44fa | 618 | pr_info("L2TP IP encapsulation support (L2TPv3)\n"); |
0d76751f JC |
619 | |
620 | err = proto_register(&l2tp_ip_prot, 1); | |
621 | if (err != 0) | |
622 | goto out; | |
623 | ||
624 | err = inet_add_protocol(&l2tp_ip_protocol, IPPROTO_L2TP); | |
625 | if (err) | |
626 | goto out1; | |
627 | ||
628 | inet_register_protosw(&l2tp_ip_protosw); | |
629 | return 0; | |
630 | ||
631 | out1: | |
632 | proto_unregister(&l2tp_ip_prot); | |
633 | out: | |
634 | return err; | |
635 | } | |
636 | ||
637 | static void __exit l2tp_ip_exit(void) | |
638 | { | |
639 | inet_unregister_protosw(&l2tp_ip_protosw); | |
640 | inet_del_protocol(&l2tp_ip_protocol, IPPROTO_L2TP); | |
641 | proto_unregister(&l2tp_ip_prot); | |
642 | } | |
643 | ||
644 | module_init(l2tp_ip_init); | |
645 | module_exit(l2tp_ip_exit); | |
646 | ||
647 | MODULE_LICENSE("GPL"); | |
648 | MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); | |
649 | MODULE_DESCRIPTION("L2TP over IP"); | |
650 | MODULE_VERSION("1.0"); | |
e8d34a88 | 651 | |
e9c54999 | 652 | /* Use the value of SOCK_DGRAM (2) directory, because __stringify doesn't like |
e8d34a88 MM |
653 | * enums |
654 | */ | |
655 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 2, IPPROTO_L2TP); |