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Commit | Line | Data |
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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 | ||
72fb96e7 | 14 | #include <asm/ioctls.h> |
0d76751f JC |
15 | #include <linux/icmp.h> |
16 | #include <linux/module.h> | |
17 | #include <linux/skbuff.h> | |
18 | #include <linux/random.h> | |
19 | #include <linux/socket.h> | |
20 | #include <linux/l2tp.h> | |
21 | #include <linux/in.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 "l2tp_core.h" | |
33 | ||
34 | struct l2tp_ip_sock { | |
35 | /* inet_sock has to be the first member of l2tp_ip_sock */ | |
36 | struct inet_sock inet; | |
37 | ||
c8657fd5 JC |
38 | u32 conn_id; |
39 | u32 peer_conn_id; | |
0d76751f JC |
40 | }; |
41 | ||
42 | static DEFINE_RWLOCK(l2tp_ip_lock); | |
43 | static struct hlist_head l2tp_ip_table; | |
44 | static struct hlist_head l2tp_ip_bind_table; | |
45 | ||
46 | static inline struct l2tp_ip_sock *l2tp_ip_sk(const struct sock *sk) | |
47 | { | |
48 | return (struct l2tp_ip_sock *)sk; | |
49 | } | |
50 | ||
a9b2dff8 GN |
51 | static struct sock *__l2tp_ip_bind_lookup(const struct net *net, __be32 laddr, |
52 | __be32 raddr, int dif, u32 tunnel_id) | |
0d76751f | 53 | { |
0d76751f JC |
54 | struct sock *sk; |
55 | ||
b67bfe0d | 56 | sk_for_each_bound(sk, &l2tp_ip_bind_table) { |
bb39b0bd GN |
57 | const struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk); |
58 | const struct inet_sock *inet = inet_sk(sk); | |
0d76751f | 59 | |
c5fdae04 GN |
60 | if (!net_eq(sock_net(sk), net)) |
61 | continue; | |
62 | ||
63 | if (sk->sk_bound_dev_if && dif && sk->sk_bound_dev_if != dif) | |
64 | continue; | |
65 | ||
66 | if (inet->inet_rcv_saddr && laddr && | |
67 | inet->inet_rcv_saddr != laddr) | |
68 | continue; | |
69 | ||
70 | if (inet->inet_daddr && raddr && inet->inet_daddr != raddr) | |
71 | continue; | |
72 | ||
73 | if (l2tp->conn_id != tunnel_id) | |
74 | continue; | |
75 | ||
76 | goto found; | |
0d76751f JC |
77 | } |
78 | ||
79 | sk = NULL; | |
80 | found: | |
81 | return sk; | |
82 | } | |
83 | ||
0d76751f JC |
84 | /* When processing receive frames, there are two cases to |
85 | * consider. Data frames consist of a non-zero session-id and an | |
86 | * optional cookie. Control frames consist of a regular L2TP header | |
87 | * preceded by 32-bits of zeros. | |
88 | * | |
89 | * L2TPv3 Session Header Over IP | |
90 | * | |
91 | * 0 1 2 3 | |
92 | * 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 | |
93 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
94 | * | Session ID | | |
95 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
96 | * | Cookie (optional, maximum 64 bits)... | |
97 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
98 | * | | |
99 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
100 | * | |
101 | * L2TPv3 Control Message Header Over IP | |
102 | * | |
103 | * 0 1 2 3 | |
104 | * 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 | |
105 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
106 | * | (32 bits of zeros) | | |
107 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
108 | * |T|L|x|x|S|x|x|x|x|x|x|x| Ver | Length | | |
109 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
110 | * | Control Connection ID | | |
111 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
112 | * | Ns | Nr | | |
113 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
114 | * | |
115 | * All control frames are passed to userspace. | |
116 | */ | |
117 | static int l2tp_ip_recv(struct sk_buff *skb) | |
118 | { | |
9d6ddb19 | 119 | struct net *net = dev_net(skb->dev); |
0d76751f JC |
120 | struct sock *sk; |
121 | u32 session_id; | |
122 | u32 tunnel_id; | |
123 | unsigned char *ptr, *optr; | |
124 | struct l2tp_session *session; | |
125 | struct l2tp_tunnel *tunnel = NULL; | |
8f7dc9ae | 126 | struct iphdr *iph; |
0d76751f | 127 | int length; |
0d76751f | 128 | |
0d76751f JC |
129 | if (!pskb_may_pull(skb, 4)) |
130 | goto discard; | |
131 | ||
5745b823 HY |
132 | /* Point to L2TP header */ |
133 | optr = ptr = skb->data; | |
0d76751f JC |
134 | session_id = ntohl(*((__be32 *) ptr)); |
135 | ptr += 4; | |
136 | ||
137 | /* RFC3931: L2TP/IP packets have the first 4 bytes containing | |
138 | * the session_id. If it is 0, the packet is a L2TP control | |
139 | * frame and the session_id value can be discarded. | |
140 | */ | |
141 | if (session_id == 0) { | |
142 | __skb_pull(skb, 4); | |
143 | goto pass_up; | |
144 | } | |
145 | ||
146 | /* Ok, this is a data packet. Lookup the session. */ | |
a4346210 | 147 | session = l2tp_session_get(net, NULL, session_id); |
61b9a047 | 148 | if (!session) |
0d76751f JC |
149 | goto discard; |
150 | ||
151 | tunnel = session->tunnel; | |
61b9a047 GN |
152 | if (!tunnel) |
153 | goto discard_sess; | |
0d76751f JC |
154 | |
155 | /* Trace packet contents, if enabled */ | |
156 | if (tunnel->debug & L2TP_MSG_DATA) { | |
157 | length = min(32u, skb->len); | |
158 | if (!pskb_may_pull(skb, length)) | |
61b9a047 | 159 | goto discard_sess; |
0d76751f | 160 | |
5745b823 HY |
161 | /* Point to L2TP header */ |
162 | optr = ptr = skb->data; | |
163 | ptr += 4; | |
a4ca44fa JP |
164 | pr_debug("%s: ip recv\n", tunnel->name); |
165 | print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length); | |
0d76751f JC |
166 | } |
167 | ||
168 | l2tp_recv_common(session, skb, ptr, optr, 0, skb->len, tunnel->recv_payload_hook); | |
61b9a047 | 169 | l2tp_session_dec_refcount(session); |
0d76751f JC |
170 | |
171 | return 0; | |
172 | ||
173 | pass_up: | |
174 | /* Get the tunnel_id from the L2TP header */ | |
175 | if (!pskb_may_pull(skb, 12)) | |
176 | goto discard; | |
177 | ||
178 | if ((skb->data[0] & 0xc0) != 0xc0) | |
179 | goto discard; | |
180 | ||
181 | tunnel_id = ntohl(*(__be32 *) &skb->data[4]); | |
8f7dc9ae GN |
182 | iph = (struct iphdr *)skb_network_header(skb); |
183 | ||
184 | read_lock_bh(&l2tp_ip_lock); | |
185 | sk = __l2tp_ip_bind_lookup(net, iph->daddr, iph->saddr, inet_iif(skb), | |
186 | tunnel_id); | |
187 | if (!sk) { | |
0d76751f | 188 | read_unlock_bh(&l2tp_ip_lock); |
8f7dc9ae | 189 | goto discard; |
0d76751f | 190 | } |
8f7dc9ae GN |
191 | sock_hold(sk); |
192 | read_unlock_bh(&l2tp_ip_lock); | |
0d76751f | 193 | |
0d76751f JC |
194 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
195 | goto discard_put; | |
196 | ||
197 | nf_reset(skb); | |
198 | ||
199 | return sk_receive_skb(sk, skb, 1); | |
200 | ||
61b9a047 | 201 | discard_sess: |
61b9a047 GN |
202 | l2tp_session_dec_refcount(session); |
203 | goto discard; | |
204 | ||
0d76751f JC |
205 | discard_put: |
206 | sock_put(sk); | |
207 | ||
208 | discard: | |
209 | kfree_skb(skb); | |
210 | return 0; | |
211 | } | |
212 | ||
213 | static int l2tp_ip_open(struct sock *sk) | |
214 | { | |
215 | /* Prevent autobind. We don't have ports. */ | |
216 | inet_sk(sk)->inet_num = IPPROTO_L2TP; | |
217 | ||
218 | write_lock_bh(&l2tp_ip_lock); | |
219 | sk_add_node(sk, &l2tp_ip_table); | |
220 | write_unlock_bh(&l2tp_ip_lock); | |
221 | ||
222 | return 0; | |
223 | } | |
224 | ||
225 | static void l2tp_ip_close(struct sock *sk, long timeout) | |
226 | { | |
227 | write_lock_bh(&l2tp_ip_lock); | |
228 | hlist_del_init(&sk->sk_bind_node); | |
d1f224ae | 229 | sk_del_node_init(sk); |
0d76751f JC |
230 | write_unlock_bh(&l2tp_ip_lock); |
231 | sk_common_release(sk); | |
232 | } | |
233 | ||
234 | static void l2tp_ip_destroy_sock(struct sock *sk) | |
235 | { | |
236 | struct sk_buff *skb; | |
02a25fee | 237 | struct l2tp_tunnel *tunnel = sk->sk_user_data; |
0d76751f JC |
238 | |
239 | while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) | |
240 | kfree_skb(skb); | |
241 | ||
02a25fee JC |
242 | if (tunnel) |
243 | l2tp_tunnel_delete(tunnel); | |
0d76751f JC |
244 | } |
245 | ||
246 | static int l2tp_ip_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
247 | { | |
248 | struct inet_sock *inet = inet_sk(sk); | |
249 | struct sockaddr_l2tpip *addr = (struct sockaddr_l2tpip *) uaddr; | |
9d6ddb19 | 250 | struct net *net = sock_net(sk); |
c51ce497 | 251 | int ret; |
0d76751f JC |
252 | int chk_addr_ret; |
253 | ||
c51ce497 JC |
254 | if (addr_len < sizeof(struct sockaddr_l2tpip)) |
255 | return -EINVAL; | |
256 | if (addr->l2tp_family != AF_INET) | |
257 | return -EINVAL; | |
258 | ||
0d76751f | 259 | lock_sock(sk); |
d5e3a190 GN |
260 | |
261 | ret = -EINVAL; | |
32c23116 GN |
262 | if (!sock_flag(sk, SOCK_ZAPPED)) |
263 | goto out; | |
264 | ||
8cf2f704 | 265 | if (sk->sk_state != TCP_CLOSE) |
0d76751f JC |
266 | goto out; |
267 | ||
9d6ddb19 | 268 | chk_addr_ret = inet_addr_type(net, addr->l2tp_addr.s_addr); |
0d76751f JC |
269 | ret = -EADDRNOTAVAIL; |
270 | if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL && | |
271 | chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST) | |
272 | goto out; | |
273 | ||
c9be48dc JC |
274 | if (addr->l2tp_addr.s_addr) |
275 | inet->inet_rcv_saddr = inet->inet_saddr = addr->l2tp_addr.s_addr; | |
0d76751f JC |
276 | if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) |
277 | inet->inet_saddr = 0; /* Use device */ | |
0d76751f | 278 | |
d5e3a190 | 279 | write_lock_bh(&l2tp_ip_lock); |
a9b2dff8 | 280 | if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr, 0, |
d5e3a190 GN |
281 | sk->sk_bound_dev_if, addr->l2tp_conn_id)) { |
282 | write_unlock_bh(&l2tp_ip_lock); | |
283 | ret = -EADDRINUSE; | |
284 | goto out; | |
285 | } | |
286 | ||
287 | sk_dst_reset(sk); | |
0d76751f JC |
288 | l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id; |
289 | ||
0d76751f JC |
290 | sk_add_bind_node(sk, &l2tp_ip_bind_table); |
291 | sk_del_node_init(sk); | |
292 | write_unlock_bh(&l2tp_ip_lock); | |
d5e3a190 | 293 | |
0d76751f | 294 | ret = 0; |
c51ce497 JC |
295 | sock_reset_flag(sk, SOCK_ZAPPED); |
296 | ||
0d76751f JC |
297 | out: |
298 | release_sock(sk); | |
299 | ||
0d76751f JC |
300 | return ret; |
301 | } | |
302 | ||
303 | static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
304 | { | |
0d76751f | 305 | struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *) uaddr; |
de3c7a18 | 306 | int rc; |
0d76751f | 307 | |
0d76751f | 308 | if (addr_len < sizeof(*lsa)) |
de3c7a18 | 309 | return -EINVAL; |
2f16270f | 310 | |
0d76751f | 311 | if (ipv4_is_multicast(lsa->l2tp_addr.s_addr)) |
de3c7a18 | 312 | return -EINVAL; |
0d76751f | 313 | |
de3c7a18 | 314 | lock_sock(sk); |
0d76751f | 315 | |
0382a25a GN |
316 | /* Must bind first - autobinding does not work */ |
317 | if (sock_flag(sk, SOCK_ZAPPED)) { | |
318 | rc = -EINVAL; | |
319 | goto out_sk; | |
320 | } | |
321 | ||
322 | rc = __ip4_datagram_connect(sk, uaddr, addr_len); | |
323 | if (rc < 0) | |
324 | goto out_sk; | |
325 | ||
0d76751f JC |
326 | l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id; |
327 | ||
0d76751f JC |
328 | write_lock_bh(&l2tp_ip_lock); |
329 | hlist_del_init(&sk->sk_bind_node); | |
330 | sk_add_bind_node(sk, &l2tp_ip_bind_table); | |
331 | write_unlock_bh(&l2tp_ip_lock); | |
332 | ||
0382a25a | 333 | out_sk: |
2f16270f | 334 | release_sock(sk); |
0382a25a | 335 | |
0d76751f JC |
336 | return rc; |
337 | } | |
338 | ||
c51ce497 JC |
339 | static int l2tp_ip_disconnect(struct sock *sk, int flags) |
340 | { | |
341 | if (sock_flag(sk, SOCK_ZAPPED)) | |
342 | return 0; | |
343 | ||
286c72de | 344 | return __udp_disconnect(sk, flags); |
c51ce497 JC |
345 | } |
346 | ||
0d76751f JC |
347 | static int l2tp_ip_getname(struct socket *sock, struct sockaddr *uaddr, |
348 | int *uaddr_len, int peer) | |
349 | { | |
350 | struct sock *sk = sock->sk; | |
351 | struct inet_sock *inet = inet_sk(sk); | |
352 | struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk); | |
353 | struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr; | |
354 | ||
355 | memset(lsa, 0, sizeof(*lsa)); | |
356 | lsa->l2tp_family = AF_INET; | |
357 | if (peer) { | |
358 | if (!inet->inet_dport) | |
359 | return -ENOTCONN; | |
360 | lsa->l2tp_conn_id = lsk->peer_conn_id; | |
361 | lsa->l2tp_addr.s_addr = inet->inet_daddr; | |
362 | } else { | |
363 | __be32 addr = inet->inet_rcv_saddr; | |
364 | if (!addr) | |
365 | addr = inet->inet_saddr; | |
366 | lsa->l2tp_conn_id = lsk->conn_id; | |
367 | lsa->l2tp_addr.s_addr = addr; | |
368 | } | |
369 | *uaddr_len = sizeof(*lsa); | |
370 | return 0; | |
371 | } | |
372 | ||
373 | static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb) | |
374 | { | |
375 | int rc; | |
376 | ||
0d76751f JC |
377 | /* Charge it to the socket, dropping if the queue is full. */ |
378 | rc = sock_queue_rcv_skb(sk, skb); | |
379 | if (rc < 0) | |
380 | goto drop; | |
381 | ||
382 | return 0; | |
383 | ||
384 | drop: | |
9d6ddb19 | 385 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS); |
0d76751f | 386 | kfree_skb(skb); |
51fb60eb | 387 | return 0; |
0d76751f JC |
388 | } |
389 | ||
390 | /* Userspace will call sendmsg() on the tunnel socket to send L2TP | |
391 | * control frames. | |
392 | */ | |
1b784140 | 393 | static int l2tp_ip_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) |
0d76751f JC |
394 | { |
395 | struct sk_buff *skb; | |
396 | int rc; | |
0d76751f | 397 | struct inet_sock *inet = inet_sk(sk); |
0d76751f | 398 | struct rtable *rt = NULL; |
fdbb0f07 | 399 | struct flowi4 *fl4; |
0d76751f JC |
400 | int connected = 0; |
401 | __be32 daddr; | |
402 | ||
2f16270f DM |
403 | lock_sock(sk); |
404 | ||
405 | rc = -ENOTCONN; | |
0d76751f | 406 | if (sock_flag(sk, SOCK_DEAD)) |
2f16270f | 407 | goto out; |
0d76751f JC |
408 | |
409 | /* Get and verify the address. */ | |
410 | if (msg->msg_name) { | |
342dfc30 | 411 | DECLARE_SOCKADDR(struct sockaddr_l2tpip *, lip, msg->msg_name); |
2f16270f | 412 | rc = -EINVAL; |
0d76751f | 413 | if (msg->msg_namelen < sizeof(*lip)) |
2f16270f | 414 | goto out; |
0d76751f JC |
415 | |
416 | if (lip->l2tp_family != AF_INET) { | |
2f16270f | 417 | rc = -EAFNOSUPPORT; |
0d76751f | 418 | if (lip->l2tp_family != AF_UNSPEC) |
2f16270f | 419 | goto out; |
0d76751f JC |
420 | } |
421 | ||
422 | daddr = lip->l2tp_addr.s_addr; | |
423 | } else { | |
84768edb | 424 | rc = -EDESTADDRREQ; |
0d76751f | 425 | if (sk->sk_state != TCP_ESTABLISHED) |
84768edb | 426 | goto out; |
0d76751f JC |
427 | |
428 | daddr = inet->inet_daddr; | |
429 | connected = 1; | |
430 | } | |
431 | ||
432 | /* Allocate a socket buffer */ | |
433 | rc = -ENOMEM; | |
434 | skb = sock_wmalloc(sk, 2 + NET_SKB_PAD + sizeof(struct iphdr) + | |
435 | 4 + len, 0, GFP_KERNEL); | |
436 | if (!skb) | |
437 | goto error; | |
438 | ||
439 | /* Reserve space for headers, putting IP header on 4-byte boundary. */ | |
440 | skb_reserve(skb, 2 + NET_SKB_PAD); | |
441 | skb_reset_network_header(skb); | |
442 | skb_reserve(skb, sizeof(struct iphdr)); | |
443 | skb_reset_transport_header(skb); | |
444 | ||
445 | /* Insert 0 session_id */ | |
446 | *((__be32 *) skb_put(skb, 4)) = 0; | |
447 | ||
448 | /* Copy user data into skb */ | |
6ce8e9ce | 449 | rc = memcpy_from_msg(skb_put(skb, len), msg, len); |
0d76751f JC |
450 | if (rc < 0) { |
451 | kfree_skb(skb); | |
452 | goto error; | |
453 | } | |
454 | ||
fdbb0f07 | 455 | fl4 = &inet->cork.fl.u.ip4; |
0d76751f JC |
456 | if (connected) |
457 | rt = (struct rtable *) __sk_dst_check(sk, 0); | |
458 | ||
081b1b1b | 459 | rcu_read_lock(); |
0d76751f | 460 | if (rt == NULL) { |
081b1b1b | 461 | const struct ip_options_rcu *inet_opt; |
f6d8bd05 | 462 | |
778865a5 | 463 | inet_opt = rcu_dereference(inet->inet_opt); |
f6d8bd05 | 464 | |
0d76751f | 465 | /* Use correct destination address if we have options. */ |
f6d8bd05 ED |
466 | if (inet_opt && inet_opt->opt.srr) |
467 | daddr = inet_opt->opt.faddr; | |
0d76751f | 468 | |
78fbfd8a DM |
469 | /* If this fails, retransmit mechanism of transport layer will |
470 | * keep trying until route appears or the connection times | |
471 | * itself out. | |
472 | */ | |
fdbb0f07 | 473 | rt = ip_route_output_ports(sock_net(sk), fl4, sk, |
78fbfd8a DM |
474 | daddr, inet->inet_saddr, |
475 | inet->inet_dport, inet->inet_sport, | |
476 | sk->sk_protocol, RT_CONN_FLAGS(sk), | |
477 | sk->sk_bound_dev_if); | |
478 | if (IS_ERR(rt)) | |
479 | goto no_route; | |
4399a4df | 480 | if (connected) { |
081b1b1b | 481 | sk_setup_caps(sk, &rt->dst); |
4399a4df ED |
482 | } else { |
483 | skb_dst_set(skb, &rt->dst); | |
484 | goto xmit; | |
485 | } | |
0d76751f | 486 | } |
081b1b1b ED |
487 | |
488 | /* We dont need to clone dst here, it is guaranteed to not disappear. | |
489 | * __dev_xmit_skb() might force a refcount if needed. | |
490 | */ | |
491 | skb_dst_set_noref(skb, &rt->dst); | |
0d76751f | 492 | |
4399a4df | 493 | xmit: |
0d76751f | 494 | /* Queue the packet to IP for output */ |
b0270e91 | 495 | rc = ip_queue_xmit(sk, skb, &inet->cork.fl); |
081b1b1b | 496 | rcu_read_unlock(); |
0d76751f JC |
497 | |
498 | error: | |
c8657fd5 | 499 | if (rc >= 0) |
0d76751f | 500 | rc = len; |
0d76751f | 501 | |
2f16270f DM |
502 | out: |
503 | release_sock(sk); | |
0d76751f JC |
504 | return rc; |
505 | ||
506 | no_route: | |
081b1b1b | 507 | rcu_read_unlock(); |
0d76751f JC |
508 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
509 | kfree_skb(skb); | |
2f16270f DM |
510 | rc = -EHOSTUNREACH; |
511 | goto out; | |
0d76751f JC |
512 | } |
513 | ||
1b784140 | 514 | static int l2tp_ip_recvmsg(struct sock *sk, struct msghdr *msg, |
0d76751f JC |
515 | size_t len, int noblock, int flags, int *addr_len) |
516 | { | |
517 | struct inet_sock *inet = inet_sk(sk); | |
0d76751f JC |
518 | size_t copied = 0; |
519 | int err = -EOPNOTSUPP; | |
342dfc30 | 520 | DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); |
0d76751f JC |
521 | struct sk_buff *skb; |
522 | ||
523 | if (flags & MSG_OOB) | |
524 | goto out; | |
525 | ||
0d76751f JC |
526 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
527 | if (!skb) | |
528 | goto out; | |
529 | ||
530 | copied = skb->len; | |
531 | if (len < copied) { | |
532 | msg->msg_flags |= MSG_TRUNC; | |
533 | copied = len; | |
534 | } | |
535 | ||
51f3d02b | 536 | err = skb_copy_datagram_msg(skb, 0, msg, copied); |
0d76751f JC |
537 | if (err) |
538 | goto done; | |
539 | ||
540 | sock_recv_timestamp(msg, sk, skb); | |
541 | ||
542 | /* Copy the address. */ | |
543 | if (sin) { | |
544 | sin->sin_family = AF_INET; | |
545 | sin->sin_addr.s_addr = ip_hdr(skb)->saddr; | |
546 | sin->sin_port = 0; | |
547 | memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); | |
bceaa902 | 548 | *addr_len = sizeof(*sin); |
0d76751f JC |
549 | } |
550 | if (inet->cmsg_flags) | |
551 | ip_cmsg_recv(msg, skb); | |
552 | if (flags & MSG_TRUNC) | |
553 | copied = skb->len; | |
554 | done: | |
555 | skb_free_datagram(sk, skb); | |
556 | out: | |
c8657fd5 | 557 | return err ? err : copied; |
0d76751f JC |
558 | } |
559 | ||
72fb96e7 ED |
560 | int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg) |
561 | { | |
562 | struct sk_buff *skb; | |
563 | int amount; | |
564 | ||
565 | switch (cmd) { | |
566 | case SIOCOUTQ: | |
567 | amount = sk_wmem_alloc_get(sk); | |
568 | break; | |
569 | case SIOCINQ: | |
570 | spin_lock_bh(&sk->sk_receive_queue.lock); | |
571 | skb = skb_peek(&sk->sk_receive_queue); | |
572 | amount = skb ? skb->len : 0; | |
573 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
574 | break; | |
575 | ||
576 | default: | |
577 | return -ENOIOCTLCMD; | |
578 | } | |
579 | ||
580 | return put_user(amount, (int __user *)arg); | |
581 | } | |
582 | EXPORT_SYMBOL(l2tp_ioctl); | |
583 | ||
fc130840 | 584 | static struct proto l2tp_ip_prot = { |
0d76751f JC |
585 | .name = "L2TP/IP", |
586 | .owner = THIS_MODULE, | |
587 | .init = l2tp_ip_open, | |
588 | .close = l2tp_ip_close, | |
589 | .bind = l2tp_ip_bind, | |
590 | .connect = l2tp_ip_connect, | |
c51ce497 | 591 | .disconnect = l2tp_ip_disconnect, |
72fb96e7 | 592 | .ioctl = l2tp_ioctl, |
0d76751f JC |
593 | .destroy = l2tp_ip_destroy_sock, |
594 | .setsockopt = ip_setsockopt, | |
595 | .getsockopt = ip_getsockopt, | |
596 | .sendmsg = l2tp_ip_sendmsg, | |
597 | .recvmsg = l2tp_ip_recvmsg, | |
598 | .backlog_rcv = l2tp_ip_backlog_recv, | |
599 | .hash = inet_hash, | |
600 | .unhash = inet_unhash, | |
601 | .obj_size = sizeof(struct l2tp_ip_sock), | |
602 | #ifdef CONFIG_COMPAT | |
603 | .compat_setsockopt = compat_ip_setsockopt, | |
604 | .compat_getsockopt = compat_ip_getsockopt, | |
605 | #endif | |
606 | }; | |
607 | ||
608 | static const struct proto_ops l2tp_ip_ops = { | |
609 | .family = PF_INET, | |
610 | .owner = THIS_MODULE, | |
611 | .release = inet_release, | |
612 | .bind = inet_bind, | |
613 | .connect = inet_dgram_connect, | |
614 | .socketpair = sock_no_socketpair, | |
615 | .accept = sock_no_accept, | |
616 | .getname = l2tp_ip_getname, | |
617 | .poll = datagram_poll, | |
618 | .ioctl = inet_ioctl, | |
619 | .listen = sock_no_listen, | |
620 | .shutdown = inet_shutdown, | |
621 | .setsockopt = sock_common_setsockopt, | |
622 | .getsockopt = sock_common_getsockopt, | |
623 | .sendmsg = inet_sendmsg, | |
624 | .recvmsg = sock_common_recvmsg, | |
625 | .mmap = sock_no_mmap, | |
626 | .sendpage = sock_no_sendpage, | |
627 | #ifdef CONFIG_COMPAT | |
628 | .compat_setsockopt = compat_sock_common_setsockopt, | |
629 | .compat_getsockopt = compat_sock_common_getsockopt, | |
630 | #endif | |
631 | }; | |
632 | ||
633 | static struct inet_protosw l2tp_ip_protosw = { | |
634 | .type = SOCK_DGRAM, | |
635 | .protocol = IPPROTO_L2TP, | |
636 | .prot = &l2tp_ip_prot, | |
637 | .ops = &l2tp_ip_ops, | |
0d76751f JC |
638 | }; |
639 | ||
640 | static struct net_protocol l2tp_ip_protocol __read_mostly = { | |
641 | .handler = l2tp_ip_recv, | |
9d6ddb19 | 642 | .netns_ok = 1, |
0d76751f JC |
643 | }; |
644 | ||
645 | static int __init l2tp_ip_init(void) | |
646 | { | |
647 | int err; | |
648 | ||
a4ca44fa | 649 | pr_info("L2TP IP encapsulation support (L2TPv3)\n"); |
0d76751f JC |
650 | |
651 | err = proto_register(&l2tp_ip_prot, 1); | |
652 | if (err != 0) | |
653 | goto out; | |
654 | ||
655 | err = inet_add_protocol(&l2tp_ip_protocol, IPPROTO_L2TP); | |
656 | if (err) | |
657 | goto out1; | |
658 | ||
659 | inet_register_protosw(&l2tp_ip_protosw); | |
660 | return 0; | |
661 | ||
662 | out1: | |
663 | proto_unregister(&l2tp_ip_prot); | |
664 | out: | |
665 | return err; | |
666 | } | |
667 | ||
668 | static void __exit l2tp_ip_exit(void) | |
669 | { | |
670 | inet_unregister_protosw(&l2tp_ip_protosw); | |
671 | inet_del_protocol(&l2tp_ip_protocol, IPPROTO_L2TP); | |
672 | proto_unregister(&l2tp_ip_prot); | |
673 | } | |
674 | ||
675 | module_init(l2tp_ip_init); | |
676 | module_exit(l2tp_ip_exit); | |
677 | ||
678 | MODULE_LICENSE("GPL"); | |
679 | MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); | |
680 | MODULE_DESCRIPTION("L2TP over IP"); | |
681 | MODULE_VERSION("1.0"); | |
e8d34a88 | 682 | |
e9c54999 | 683 | /* Use the value of SOCK_DGRAM (2) directory, because __stringify doesn't like |
e8d34a88 MM |
684 | * enums |
685 | */ | |
686 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 2, IPPROTO_L2TP); | |
163c2e25 | 687 | MODULE_ALIAS_NET_PF_PROTO(PF_INET, IPPROTO_L2TP); |