Commit | Line | Data |
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fd558d18 JC |
1 | /* |
2 | * L2TP core. | |
3 | * | |
4 | * Copyright (c) 2008,2009,2010 Katalix Systems Ltd | |
5 | * | |
6 | * This file contains some code of the original L2TPv2 pppol2tp | |
7 | * driver, which has the following copyright: | |
8 | * | |
9 | * Authors: Martijn van Oosterhout <kleptog@svana.org> | |
10 | * James Chapman (jchapman@katalix.com) | |
11 | * Contributors: | |
12 | * Michal Ostrowski <mostrows@speakeasy.net> | |
13 | * Arnaldo Carvalho de Melo <acme@xconectiva.com.br> | |
14 | * David S. Miller (davem@redhat.com) | |
15 | * | |
16 | * This program is free software; you can redistribute it and/or modify | |
17 | * it under the terms of the GNU General Public License version 2 as | |
18 | * published by the Free Software Foundation. | |
19 | */ | |
20 | ||
a4ca44fa JP |
21 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
22 | ||
fd558d18 JC |
23 | #include <linux/module.h> |
24 | #include <linux/string.h> | |
25 | #include <linux/list.h> | |
e02d494d | 26 | #include <linux/rculist.h> |
fd558d18 JC |
27 | #include <linux/uaccess.h> |
28 | ||
29 | #include <linux/kernel.h> | |
30 | #include <linux/spinlock.h> | |
31 | #include <linux/kthread.h> | |
32 | #include <linux/sched.h> | |
33 | #include <linux/slab.h> | |
34 | #include <linux/errno.h> | |
35 | #include <linux/jiffies.h> | |
36 | ||
37 | #include <linux/netdevice.h> | |
38 | #include <linux/net.h> | |
39 | #include <linux/inetdevice.h> | |
40 | #include <linux/skbuff.h> | |
41 | #include <linux/init.h> | |
0d76751f | 42 | #include <linux/in.h> |
fd558d18 JC |
43 | #include <linux/ip.h> |
44 | #include <linux/udp.h> | |
0d76751f | 45 | #include <linux/l2tp.h> |
fd558d18 JC |
46 | #include <linux/hash.h> |
47 | #include <linux/sort.h> | |
48 | #include <linux/file.h> | |
49 | #include <linux/nsproxy.h> | |
50 | #include <net/net_namespace.h> | |
51 | #include <net/netns/generic.h> | |
52 | #include <net/dst.h> | |
53 | #include <net/ip.h> | |
54 | #include <net/udp.h> | |
309795f4 | 55 | #include <net/inet_common.h> |
fd558d18 | 56 | #include <net/xfrm.h> |
0d76751f | 57 | #include <net/protocol.h> |
d2cf3361 BL |
58 | #include <net/inet6_connection_sock.h> |
59 | #include <net/inet_ecn.h> | |
60 | #include <net/ip6_route.h> | |
d499bd2e | 61 | #include <net/ip6_checksum.h> |
fd558d18 JC |
62 | |
63 | #include <asm/byteorder.h> | |
60063497 | 64 | #include <linux/atomic.h> |
fd558d18 JC |
65 | |
66 | #include "l2tp_core.h" | |
67 | ||
68 | #define L2TP_DRV_VERSION "V2.0" | |
69 | ||
70 | /* L2TP header constants */ | |
71 | #define L2TP_HDRFLAG_T 0x8000 | |
72 | #define L2TP_HDRFLAG_L 0x4000 | |
73 | #define L2TP_HDRFLAG_S 0x0800 | |
74 | #define L2TP_HDRFLAG_O 0x0200 | |
75 | #define L2TP_HDRFLAG_P 0x0100 | |
76 | ||
77 | #define L2TP_HDR_VER_MASK 0x000F | |
78 | #define L2TP_HDR_VER_2 0x0002 | |
f7faffa3 | 79 | #define L2TP_HDR_VER_3 0x0003 |
fd558d18 JC |
80 | |
81 | /* L2TPv3 default L2-specific sublayer */ | |
82 | #define L2TP_SLFLAG_S 0x40000000 | |
83 | #define L2TP_SL_SEQ_MASK 0x00ffffff | |
84 | ||
85 | #define L2TP_HDR_SIZE_SEQ 10 | |
86 | #define L2TP_HDR_SIZE_NOSEQ 6 | |
87 | ||
88 | /* Default trace flags */ | |
89 | #define L2TP_DEFAULT_DEBUG_FLAGS 0 | |
90 | ||
fd558d18 JC |
91 | /* Private data stored for received packets in the skb. |
92 | */ | |
93 | struct l2tp_skb_cb { | |
f7faffa3 | 94 | u32 ns; |
fd558d18 JC |
95 | u16 has_seq; |
96 | u16 length; | |
97 | unsigned long expires; | |
98 | }; | |
99 | ||
100 | #define L2TP_SKB_CB(skb) ((struct l2tp_skb_cb *) &skb->cb[sizeof(struct inet_skb_parm)]) | |
101 | ||
102 | static atomic_t l2tp_tunnel_count; | |
103 | static atomic_t l2tp_session_count; | |
f8ccac0e | 104 | static struct workqueue_struct *l2tp_wq; |
fd558d18 JC |
105 | |
106 | /* per-net private data for this module */ | |
107 | static unsigned int l2tp_net_id; | |
108 | struct l2tp_net { | |
109 | struct list_head l2tp_tunnel_list; | |
e02d494d | 110 | spinlock_t l2tp_tunnel_list_lock; |
f7faffa3 | 111 | struct hlist_head l2tp_session_hlist[L2TP_HASH_SIZE_2]; |
e02d494d | 112 | spinlock_t l2tp_session_hlist_lock; |
fd558d18 JC |
113 | }; |
114 | ||
fc130840 | 115 | static void l2tp_session_set_header_len(struct l2tp_session *session, int version); |
116 | static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel); | |
fc130840 | 117 | |
d980ed62 DM |
118 | static inline struct l2tp_tunnel *l2tp_tunnel(struct sock *sk) |
119 | { | |
120 | return sk->sk_user_data; | |
121 | } | |
122 | ||
fd558d18 JC |
123 | static inline struct l2tp_net *l2tp_pernet(struct net *net) |
124 | { | |
125 | BUG_ON(!net); | |
126 | ||
127 | return net_generic(net, l2tp_net_id); | |
128 | } | |
129 | ||
fc130840 | 130 | /* Tunnel reference counts. Incremented per session that is added to |
131 | * the tunnel. | |
132 | */ | |
133 | static inline void l2tp_tunnel_inc_refcount_1(struct l2tp_tunnel *tunnel) | |
134 | { | |
135 | atomic_inc(&tunnel->ref_count); | |
136 | } | |
137 | ||
138 | static inline void l2tp_tunnel_dec_refcount_1(struct l2tp_tunnel *tunnel) | |
139 | { | |
140 | if (atomic_dec_and_test(&tunnel->ref_count)) | |
141 | l2tp_tunnel_free(tunnel); | |
142 | } | |
143 | #ifdef L2TP_REFCNT_DEBUG | |
a4ca44fa JP |
144 | #define l2tp_tunnel_inc_refcount(_t) \ |
145 | do { \ | |
146 | pr_debug("l2tp_tunnel_inc_refcount: %s:%d %s: cnt=%d\n", \ | |
147 | __func__, __LINE__, (_t)->name, \ | |
148 | atomic_read(&_t->ref_count)); \ | |
149 | l2tp_tunnel_inc_refcount_1(_t); \ | |
150 | } while (0) | |
151 | #define l2tp_tunnel_dec_refcount(_t) | |
152 | do { \ | |
153 | pr_debug("l2tp_tunnel_dec_refcount: %s:%d %s: cnt=%d\n", \ | |
154 | __func__, __LINE__, (_t)->name, \ | |
155 | atomic_read(&_t->ref_count)); \ | |
156 | l2tp_tunnel_dec_refcount_1(_t); \ | |
157 | } while (0) | |
fc130840 | 158 | #else |
159 | #define l2tp_tunnel_inc_refcount(t) l2tp_tunnel_inc_refcount_1(t) | |
160 | #define l2tp_tunnel_dec_refcount(t) l2tp_tunnel_dec_refcount_1(t) | |
161 | #endif | |
162 | ||
f7faffa3 JC |
163 | /* Session hash global list for L2TPv3. |
164 | * The session_id SHOULD be random according to RFC3931, but several | |
165 | * L2TP implementations use incrementing session_ids. So we do a real | |
166 | * hash on the session_id, rather than a simple bitmask. | |
167 | */ | |
168 | static inline struct hlist_head * | |
169 | l2tp_session_id_hash_2(struct l2tp_net *pn, u32 session_id) | |
170 | { | |
171 | return &pn->l2tp_session_hlist[hash_32(session_id, L2TP_HASH_BITS_2)]; | |
172 | ||
173 | } | |
174 | ||
80d84ef3 TP |
175 | /* Lookup the tunnel socket, possibly involving the fs code if the socket is |
176 | * owned by userspace. A struct sock returned from this function must be | |
177 | * released using l2tp_tunnel_sock_put once you're done with it. | |
178 | */ | |
179 | struct sock *l2tp_tunnel_sock_lookup(struct l2tp_tunnel *tunnel) | |
180 | { | |
181 | int err = 0; | |
182 | struct socket *sock = NULL; | |
183 | struct sock *sk = NULL; | |
184 | ||
185 | if (!tunnel) | |
186 | goto out; | |
187 | ||
188 | if (tunnel->fd >= 0) { | |
189 | /* Socket is owned by userspace, who might be in the process | |
190 | * of closing it. Look the socket up using the fd to ensure | |
191 | * consistency. | |
192 | */ | |
193 | sock = sockfd_lookup(tunnel->fd, &err); | |
194 | if (sock) | |
195 | sk = sock->sk; | |
196 | } else { | |
197 | /* Socket is owned by kernelspace */ | |
198 | sk = tunnel->sock; | |
8abbbe8f | 199 | sock_hold(sk); |
80d84ef3 TP |
200 | } |
201 | ||
202 | out: | |
203 | return sk; | |
204 | } | |
205 | EXPORT_SYMBOL_GPL(l2tp_tunnel_sock_lookup); | |
206 | ||
207 | /* Drop a reference to a tunnel socket obtained via. l2tp_tunnel_sock_put */ | |
208 | void l2tp_tunnel_sock_put(struct sock *sk) | |
209 | { | |
210 | struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); | |
211 | if (tunnel) { | |
212 | if (tunnel->fd >= 0) { | |
213 | /* Socket is owned by userspace */ | |
214 | sockfd_put(sk->sk_socket); | |
215 | } | |
216 | sock_put(sk); | |
217 | } | |
8abbbe8f | 218 | sock_put(sk); |
80d84ef3 TP |
219 | } |
220 | EXPORT_SYMBOL_GPL(l2tp_tunnel_sock_put); | |
221 | ||
f7faffa3 JC |
222 | /* Lookup a session by id in the global session list |
223 | */ | |
224 | static struct l2tp_session *l2tp_session_find_2(struct net *net, u32 session_id) | |
225 | { | |
226 | struct l2tp_net *pn = l2tp_pernet(net); | |
227 | struct hlist_head *session_list = | |
228 | l2tp_session_id_hash_2(pn, session_id); | |
229 | struct l2tp_session *session; | |
f7faffa3 | 230 | |
e02d494d | 231 | rcu_read_lock_bh(); |
b67bfe0d | 232 | hlist_for_each_entry_rcu(session, session_list, global_hlist) { |
f7faffa3 | 233 | if (session->session_id == session_id) { |
e02d494d | 234 | rcu_read_unlock_bh(); |
f7faffa3 JC |
235 | return session; |
236 | } | |
237 | } | |
e02d494d | 238 | rcu_read_unlock_bh(); |
f7faffa3 JC |
239 | |
240 | return NULL; | |
241 | } | |
242 | ||
fd558d18 JC |
243 | /* Session hash list. |
244 | * The session_id SHOULD be random according to RFC2661, but several | |
245 | * L2TP implementations (Cisco and Microsoft) use incrementing | |
246 | * session_ids. So we do a real hash on the session_id, rather than a | |
247 | * simple bitmask. | |
248 | */ | |
249 | static inline struct hlist_head * | |
250 | l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id) | |
251 | { | |
252 | return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)]; | |
253 | } | |
254 | ||
255 | /* Lookup a session by id | |
256 | */ | |
f7faffa3 | 257 | struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunnel, u32 session_id) |
fd558d18 | 258 | { |
f7faffa3 | 259 | struct hlist_head *session_list; |
fd558d18 | 260 | struct l2tp_session *session; |
fd558d18 | 261 | |
f7faffa3 JC |
262 | /* In L2TPv3, session_ids are unique over all tunnels and we |
263 | * sometimes need to look them up before we know the | |
264 | * tunnel. | |
265 | */ | |
266 | if (tunnel == NULL) | |
267 | return l2tp_session_find_2(net, session_id); | |
268 | ||
269 | session_list = l2tp_session_id_hash(tunnel, session_id); | |
fd558d18 | 270 | read_lock_bh(&tunnel->hlist_lock); |
b67bfe0d | 271 | hlist_for_each_entry(session, session_list, hlist) { |
fd558d18 JC |
272 | if (session->session_id == session_id) { |
273 | read_unlock_bh(&tunnel->hlist_lock); | |
274 | return session; | |
275 | } | |
276 | } | |
277 | read_unlock_bh(&tunnel->hlist_lock); | |
278 | ||
279 | return NULL; | |
280 | } | |
281 | EXPORT_SYMBOL_GPL(l2tp_session_find); | |
282 | ||
43f8c8b0 GN |
283 | struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth, |
284 | bool do_ref) | |
fd558d18 JC |
285 | { |
286 | int hash; | |
fd558d18 JC |
287 | struct l2tp_session *session; |
288 | int count = 0; | |
289 | ||
290 | read_lock_bh(&tunnel->hlist_lock); | |
291 | for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { | |
b67bfe0d | 292 | hlist_for_each_entry(session, &tunnel->session_hlist[hash], hlist) { |
fd558d18 | 293 | if (++count > nth) { |
43f8c8b0 GN |
294 | l2tp_session_inc_refcount(session); |
295 | if (do_ref && session->ref) | |
296 | session->ref(session); | |
fd558d18 JC |
297 | read_unlock_bh(&tunnel->hlist_lock); |
298 | return session; | |
299 | } | |
300 | } | |
301 | } | |
302 | ||
303 | read_unlock_bh(&tunnel->hlist_lock); | |
304 | ||
305 | return NULL; | |
306 | } | |
43f8c8b0 | 307 | EXPORT_SYMBOL_GPL(l2tp_session_get_nth); |
fd558d18 | 308 | |
309795f4 JC |
309 | /* Lookup a session by interface name. |
310 | * This is very inefficient but is only used by management interfaces. | |
311 | */ | |
312 | struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) | |
313 | { | |
314 | struct l2tp_net *pn = l2tp_pernet(net); | |
315 | int hash; | |
309795f4 JC |
316 | struct l2tp_session *session; |
317 | ||
e02d494d | 318 | rcu_read_lock_bh(); |
309795f4 | 319 | for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) { |
b67bfe0d | 320 | hlist_for_each_entry_rcu(session, &pn->l2tp_session_hlist[hash], global_hlist) { |
309795f4 | 321 | if (!strcmp(session->ifname, ifname)) { |
e02d494d | 322 | rcu_read_unlock_bh(); |
309795f4 JC |
323 | return session; |
324 | } | |
325 | } | |
326 | } | |
327 | ||
e02d494d | 328 | rcu_read_unlock_bh(); |
309795f4 JC |
329 | |
330 | return NULL; | |
331 | } | |
332 | EXPORT_SYMBOL_GPL(l2tp_session_find_by_ifname); | |
333 | ||
fd558d18 JC |
334 | /* Lookup a tunnel by id |
335 | */ | |
336 | struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id) | |
337 | { | |
338 | struct l2tp_tunnel *tunnel; | |
339 | struct l2tp_net *pn = l2tp_pernet(net); | |
340 | ||
e02d494d JC |
341 | rcu_read_lock_bh(); |
342 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { | |
fd558d18 | 343 | if (tunnel->tunnel_id == tunnel_id) { |
e02d494d | 344 | rcu_read_unlock_bh(); |
fd558d18 JC |
345 | return tunnel; |
346 | } | |
347 | } | |
e02d494d | 348 | rcu_read_unlock_bh(); |
fd558d18 JC |
349 | |
350 | return NULL; | |
351 | } | |
352 | EXPORT_SYMBOL_GPL(l2tp_tunnel_find); | |
353 | ||
354 | struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth) | |
355 | { | |
356 | struct l2tp_net *pn = l2tp_pernet(net); | |
357 | struct l2tp_tunnel *tunnel; | |
358 | int count = 0; | |
359 | ||
e02d494d JC |
360 | rcu_read_lock_bh(); |
361 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { | |
fd558d18 | 362 | if (++count > nth) { |
e02d494d | 363 | rcu_read_unlock_bh(); |
fd558d18 JC |
364 | return tunnel; |
365 | } | |
366 | } | |
367 | ||
e02d494d | 368 | rcu_read_unlock_bh(); |
fd558d18 JC |
369 | |
370 | return NULL; | |
371 | } | |
372 | EXPORT_SYMBOL_GPL(l2tp_tunnel_find_nth); | |
373 | ||
374 | /***************************************************************************** | |
375 | * Receive data handling | |
376 | *****************************************************************************/ | |
377 | ||
378 | /* Queue a skb in order. We come here only if the skb has an L2TP sequence | |
379 | * number. | |
380 | */ | |
381 | static void l2tp_recv_queue_skb(struct l2tp_session *session, struct sk_buff *skb) | |
382 | { | |
383 | struct sk_buff *skbp; | |
384 | struct sk_buff *tmp; | |
f7faffa3 | 385 | u32 ns = L2TP_SKB_CB(skb)->ns; |
fd558d18 JC |
386 | |
387 | spin_lock_bh(&session->reorder_q.lock); | |
388 | skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { | |
389 | if (L2TP_SKB_CB(skbp)->ns > ns) { | |
390 | __skb_queue_before(&session->reorder_q, skbp, skb); | |
a4ca44fa JP |
391 | l2tp_dbg(session, L2TP_MSG_SEQ, |
392 | "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n", | |
393 | session->name, ns, L2TP_SKB_CB(skbp)->ns, | |
394 | skb_queue_len(&session->reorder_q)); | |
7b7c0719 | 395 | atomic_long_inc(&session->stats.rx_oos_packets); |
fd558d18 JC |
396 | goto out; |
397 | } | |
398 | } | |
399 | ||
400 | __skb_queue_tail(&session->reorder_q, skb); | |
401 | ||
402 | out: | |
403 | spin_unlock_bh(&session->reorder_q.lock); | |
404 | } | |
405 | ||
406 | /* Dequeue a single skb. | |
407 | */ | |
408 | static void l2tp_recv_dequeue_skb(struct l2tp_session *session, struct sk_buff *skb) | |
409 | { | |
410 | struct l2tp_tunnel *tunnel = session->tunnel; | |
411 | int length = L2TP_SKB_CB(skb)->length; | |
412 | ||
413 | /* We're about to requeue the skb, so return resources | |
414 | * to its current owner (a socket receive buffer). | |
415 | */ | |
416 | skb_orphan(skb); | |
417 | ||
7b7c0719 TP |
418 | atomic_long_inc(&tunnel->stats.rx_packets); |
419 | atomic_long_add(length, &tunnel->stats.rx_bytes); | |
420 | atomic_long_inc(&session->stats.rx_packets); | |
421 | atomic_long_add(length, &session->stats.rx_bytes); | |
fd558d18 JC |
422 | |
423 | if (L2TP_SKB_CB(skb)->has_seq) { | |
424 | /* Bump our Nr */ | |
425 | session->nr++; | |
f7faffa3 JC |
426 | if (tunnel->version == L2TP_HDR_VER_2) |
427 | session->nr &= 0xffff; | |
428 | else | |
429 | session->nr &= 0xffffff; | |
430 | ||
a4ca44fa JP |
431 | l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated nr to %hu\n", |
432 | session->name, session->nr); | |
fd558d18 JC |
433 | } |
434 | ||
435 | /* call private receive handler */ | |
436 | if (session->recv_skb != NULL) | |
437 | (*session->recv_skb)(session, skb, L2TP_SKB_CB(skb)->length); | |
438 | else | |
439 | kfree_skb(skb); | |
440 | ||
441 | if (session->deref) | |
442 | (*session->deref)(session); | |
443 | } | |
444 | ||
445 | /* Dequeue skbs from the session's reorder_q, subject to packet order. | |
446 | * Skbs that have been in the queue for too long are simply discarded. | |
447 | */ | |
448 | static void l2tp_recv_dequeue(struct l2tp_session *session) | |
449 | { | |
450 | struct sk_buff *skb; | |
451 | struct sk_buff *tmp; | |
452 | ||
453 | /* If the pkt at the head of the queue has the nr that we | |
454 | * expect to send up next, dequeue it and any other | |
455 | * in-sequence packets behind it. | |
456 | */ | |
e2e210c0 | 457 | start: |
fd558d18 JC |
458 | spin_lock_bh(&session->reorder_q.lock); |
459 | skb_queue_walk_safe(&session->reorder_q, skb, tmp) { | |
460 | if (time_after(jiffies, L2TP_SKB_CB(skb)->expires)) { | |
7b7c0719 TP |
461 | atomic_long_inc(&session->stats.rx_seq_discards); |
462 | atomic_long_inc(&session->stats.rx_errors); | |
a4ca44fa JP |
463 | l2tp_dbg(session, L2TP_MSG_SEQ, |
464 | "%s: oos pkt %u len %d discarded (too old), waiting for %u, reorder_q_len=%d\n", | |
465 | session->name, L2TP_SKB_CB(skb)->ns, | |
466 | L2TP_SKB_CB(skb)->length, session->nr, | |
467 | skb_queue_len(&session->reorder_q)); | |
38d40b3f | 468 | session->reorder_skip = 1; |
fd558d18 JC |
469 | __skb_unlink(skb, &session->reorder_q); |
470 | kfree_skb(skb); | |
471 | if (session->deref) | |
472 | (*session->deref)(session); | |
473 | continue; | |
474 | } | |
475 | ||
476 | if (L2TP_SKB_CB(skb)->has_seq) { | |
38d40b3f | 477 | if (session->reorder_skip) { |
a4ca44fa JP |
478 | l2tp_dbg(session, L2TP_MSG_SEQ, |
479 | "%s: advancing nr to next pkt: %u -> %u", | |
480 | session->name, session->nr, | |
481 | L2TP_SKB_CB(skb)->ns); | |
38d40b3f JC |
482 | session->reorder_skip = 0; |
483 | session->nr = L2TP_SKB_CB(skb)->ns; | |
484 | } | |
fd558d18 | 485 | if (L2TP_SKB_CB(skb)->ns != session->nr) { |
a4ca44fa JP |
486 | l2tp_dbg(session, L2TP_MSG_SEQ, |
487 | "%s: holding oos pkt %u len %d, waiting for %u, reorder_q_len=%d\n", | |
488 | session->name, L2TP_SKB_CB(skb)->ns, | |
489 | L2TP_SKB_CB(skb)->length, session->nr, | |
490 | skb_queue_len(&session->reorder_q)); | |
fd558d18 JC |
491 | goto out; |
492 | } | |
493 | } | |
494 | __skb_unlink(skb, &session->reorder_q); | |
495 | ||
496 | /* Process the skb. We release the queue lock while we | |
497 | * do so to let other contexts process the queue. | |
498 | */ | |
499 | spin_unlock_bh(&session->reorder_q.lock); | |
500 | l2tp_recv_dequeue_skb(session, skb); | |
e2e210c0 | 501 | goto start; |
fd558d18 JC |
502 | } |
503 | ||
504 | out: | |
505 | spin_unlock_bh(&session->reorder_q.lock); | |
506 | } | |
507 | ||
508 | static inline int l2tp_verify_udp_checksum(struct sock *sk, | |
509 | struct sk_buff *skb) | |
510 | { | |
511 | struct udphdr *uh = udp_hdr(skb); | |
512 | u16 ulen = ntohs(uh->len); | |
fd558d18 JC |
513 | __wsum psum; |
514 | ||
d2cf3361 | 515 | if (sk->sk_no_check || skb_csum_unnecessary(skb)) |
fd558d18 JC |
516 | return 0; |
517 | ||
d2cf3361 | 518 | #if IS_ENABLED(CONFIG_IPV6) |
d980ed62 | 519 | if (sk->sk_family == PF_INET6 && !l2tp_tunnel(sk)->v4mapped) { |
d2cf3361 BL |
520 | if (!uh->check) { |
521 | LIMIT_NETDEBUG(KERN_INFO "L2TP: IPv6: checksum is 0\n"); | |
522 | return 1; | |
523 | } | |
524 | if ((skb->ip_summed == CHECKSUM_COMPLETE) && | |
525 | !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, | |
526 | &ipv6_hdr(skb)->daddr, ulen, | |
527 | IPPROTO_UDP, skb->csum)) { | |
528 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
529 | return 0; | |
530 | } | |
531 | skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, | |
532 | &ipv6_hdr(skb)->daddr, | |
533 | skb->len, IPPROTO_UDP, | |
534 | 0)); | |
535 | } else | |
536 | #endif | |
537 | { | |
538 | struct inet_sock *inet; | |
539 | if (!uh->check) | |
540 | return 0; | |
541 | inet = inet_sk(sk); | |
542 | psum = csum_tcpudp_nofold(inet->inet_saddr, inet->inet_daddr, | |
543 | ulen, IPPROTO_UDP, 0); | |
544 | ||
545 | if ((skb->ip_summed == CHECKSUM_COMPLETE) && | |
546 | !csum_fold(csum_add(psum, skb->csum))) | |
547 | return 0; | |
548 | skb->csum = psum; | |
549 | } | |
fd558d18 JC |
550 | |
551 | return __skb_checksum_complete(skb); | |
552 | } | |
553 | ||
f7faffa3 JC |
554 | /* Do receive processing of L2TP data frames. We handle both L2TPv2 |
555 | * and L2TPv3 data frames here. | |
556 | * | |
557 | * L2TPv2 Data Message Header | |
558 | * | |
559 | * 0 1 2 3 | |
560 | * 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 | |
561 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
562 | * |T|L|x|x|S|x|O|P|x|x|x|x| Ver | Length (opt) | | |
563 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
564 | * | Tunnel ID | Session ID | | |
565 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
566 | * | Ns (opt) | Nr (opt) | | |
567 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
568 | * | Offset Size (opt) | Offset pad... (opt) | |
569 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
570 | * | |
571 | * Data frames are marked by T=0. All other fields are the same as | |
572 | * those in L2TP control frames. | |
573 | * | |
574 | * L2TPv3 Data Message Header | |
575 | * | |
576 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
577 | * | L2TP Session Header | | |
578 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
579 | * | L2-Specific Sublayer | | |
580 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
581 | * | Tunnel Payload ... | |
582 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
583 | * | |
584 | * L2TPv3 Session Header Over IP | |
585 | * | |
586 | * 0 1 2 3 | |
587 | * 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 | |
588 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
589 | * | Session ID | | |
590 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
591 | * | Cookie (optional, maximum 64 bits)... | |
592 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
593 | * | | |
594 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
595 | * | |
596 | * L2TPv3 L2-Specific Sublayer Format | |
597 | * | |
598 | * 0 1 2 3 | |
599 | * 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 | |
600 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
601 | * |x|S|x|x|x|x|x|x| Sequence Number | | |
602 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
603 | * | |
604 | * Cookie value, sublayer format and offset (pad) are negotiated with | |
605 | * the peer when the session is set up. Unlike L2TPv2, we do not need | |
606 | * to parse the packet header to determine if optional fields are | |
607 | * present. | |
608 | * | |
609 | * Caller must already have parsed the frame and determined that it is | |
610 | * a data (not control) frame before coming here. Fields up to the | |
611 | * session-id have already been parsed and ptr points to the data | |
612 | * after the session-id. | |
fd558d18 | 613 | */ |
f7faffa3 JC |
614 | void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, |
615 | unsigned char *ptr, unsigned char *optr, u16 hdrflags, | |
616 | int length, int (*payload_hook)(struct sk_buff *skb)) | |
fd558d18 | 617 | { |
f7faffa3 | 618 | struct l2tp_tunnel *tunnel = session->tunnel; |
fd558d18 | 619 | int offset; |
f7faffa3 | 620 | u32 ns, nr; |
fd558d18 JC |
621 | |
622 | /* The ref count is increased since we now hold a pointer to | |
623 | * the session. Take care to decrement the refcnt when exiting | |
624 | * this function from now on... | |
625 | */ | |
626 | l2tp_session_inc_refcount(session); | |
627 | if (session->ref) | |
628 | (*session->ref)(session); | |
629 | ||
f7faffa3 JC |
630 | /* Parse and check optional cookie */ |
631 | if (session->peer_cookie_len > 0) { | |
632 | if (memcmp(ptr, &session->peer_cookie[0], session->peer_cookie_len)) { | |
a4ca44fa JP |
633 | l2tp_info(tunnel, L2TP_MSG_DATA, |
634 | "%s: cookie mismatch (%u/%u). Discarding.\n", | |
635 | tunnel->name, tunnel->tunnel_id, | |
636 | session->session_id); | |
7b7c0719 | 637 | atomic_long_inc(&session->stats.rx_cookie_discards); |
f7faffa3 JC |
638 | goto discard; |
639 | } | |
640 | ptr += session->peer_cookie_len; | |
641 | } | |
642 | ||
fd558d18 JC |
643 | /* Handle the optional sequence numbers. Sequence numbers are |
644 | * in different places for L2TPv2 and L2TPv3. | |
645 | * | |
646 | * If we are the LAC, enable/disable sequence numbers under | |
647 | * the control of the LNS. If no sequence numbers present but | |
648 | * we were expecting them, discard frame. | |
649 | */ | |
650 | ns = nr = 0; | |
651 | L2TP_SKB_CB(skb)->has_seq = 0; | |
f7faffa3 JC |
652 | if (tunnel->version == L2TP_HDR_VER_2) { |
653 | if (hdrflags & L2TP_HDRFLAG_S) { | |
654 | ns = ntohs(*(__be16 *) ptr); | |
655 | ptr += 2; | |
656 | nr = ntohs(*(__be16 *) ptr); | |
657 | ptr += 2; | |
fd558d18 | 658 | |
f7faffa3 JC |
659 | /* Store L2TP info in the skb */ |
660 | L2TP_SKB_CB(skb)->ns = ns; | |
661 | L2TP_SKB_CB(skb)->has_seq = 1; | |
fd558d18 | 662 | |
a4ca44fa JP |
663 | l2tp_dbg(session, L2TP_MSG_SEQ, |
664 | "%s: recv data ns=%u, nr=%u, session nr=%u\n", | |
665 | session->name, ns, nr, session->nr); | |
f7faffa3 JC |
666 | } |
667 | } else if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { | |
668 | u32 l2h = ntohl(*(__be32 *) ptr); | |
669 | ||
670 | if (l2h & 0x40000000) { | |
671 | ns = l2h & 0x00ffffff; | |
672 | ||
673 | /* Store L2TP info in the skb */ | |
674 | L2TP_SKB_CB(skb)->ns = ns; | |
675 | L2TP_SKB_CB(skb)->has_seq = 1; | |
676 | ||
a4ca44fa JP |
677 | l2tp_dbg(session, L2TP_MSG_SEQ, |
678 | "%s: recv data ns=%u, session nr=%u\n", | |
679 | session->name, ns, session->nr); | |
f7faffa3 | 680 | } |
fd558d18 JC |
681 | } |
682 | ||
f7faffa3 JC |
683 | /* Advance past L2-specific header, if present */ |
684 | ptr += session->l2specific_len; | |
685 | ||
fd558d18 JC |
686 | if (L2TP_SKB_CB(skb)->has_seq) { |
687 | /* Received a packet with sequence numbers. If we're the LNS, | |
688 | * check if we sre sending sequence numbers and if not, | |
689 | * configure it so. | |
690 | */ | |
691 | if ((!session->lns_mode) && (!session->send_seq)) { | |
a4ca44fa JP |
692 | l2tp_info(session, L2TP_MSG_SEQ, |
693 | "%s: requested to enable seq numbers by LNS\n", | |
694 | session->name); | |
fd558d18 | 695 | session->send_seq = -1; |
f7faffa3 | 696 | l2tp_session_set_header_len(session, tunnel->version); |
fd558d18 JC |
697 | } |
698 | } else { | |
699 | /* No sequence numbers. | |
700 | * If user has configured mandatory sequence numbers, discard. | |
701 | */ | |
702 | if (session->recv_seq) { | |
a4ca44fa JP |
703 | l2tp_warn(session, L2TP_MSG_SEQ, |
704 | "%s: recv data has no seq numbers when required. Discarding.\n", | |
705 | session->name); | |
7b7c0719 | 706 | atomic_long_inc(&session->stats.rx_seq_discards); |
fd558d18 JC |
707 | goto discard; |
708 | } | |
709 | ||
710 | /* If we're the LAC and we're sending sequence numbers, the | |
711 | * LNS has requested that we no longer send sequence numbers. | |
712 | * If we're the LNS and we're sending sequence numbers, the | |
713 | * LAC is broken. Discard the frame. | |
714 | */ | |
715 | if ((!session->lns_mode) && (session->send_seq)) { | |
a4ca44fa JP |
716 | l2tp_info(session, L2TP_MSG_SEQ, |
717 | "%s: requested to disable seq numbers by LNS\n", | |
718 | session->name); | |
fd558d18 | 719 | session->send_seq = 0; |
f7faffa3 | 720 | l2tp_session_set_header_len(session, tunnel->version); |
fd558d18 | 721 | } else if (session->send_seq) { |
a4ca44fa JP |
722 | l2tp_warn(session, L2TP_MSG_SEQ, |
723 | "%s: recv data has no seq numbers when required. Discarding.\n", | |
724 | session->name); | |
7b7c0719 | 725 | atomic_long_inc(&session->stats.rx_seq_discards); |
fd558d18 JC |
726 | goto discard; |
727 | } | |
728 | } | |
729 | ||
f7faffa3 JC |
730 | /* Session data offset is handled differently for L2TPv2 and |
731 | * L2TPv3. For L2TPv2, there is an optional 16-bit value in | |
732 | * the header. For L2TPv3, the offset is negotiated using AVPs | |
733 | * in the session setup control protocol. | |
734 | */ | |
735 | if (tunnel->version == L2TP_HDR_VER_2) { | |
736 | /* If offset bit set, skip it. */ | |
737 | if (hdrflags & L2TP_HDRFLAG_O) { | |
738 | offset = ntohs(*(__be16 *)ptr); | |
739 | ptr += 2 + offset; | |
740 | } | |
741 | } else | |
742 | ptr += session->offset; | |
fd558d18 JC |
743 | |
744 | offset = ptr - optr; | |
745 | if (!pskb_may_pull(skb, offset)) | |
746 | goto discard; | |
747 | ||
748 | __skb_pull(skb, offset); | |
749 | ||
750 | /* If caller wants to process the payload before we queue the | |
751 | * packet, do so now. | |
752 | */ | |
753 | if (payload_hook) | |
754 | if ((*payload_hook)(skb)) | |
755 | goto discard; | |
756 | ||
757 | /* Prepare skb for adding to the session's reorder_q. Hold | |
758 | * packets for max reorder_timeout or 1 second if not | |
759 | * reordering. | |
760 | */ | |
761 | L2TP_SKB_CB(skb)->length = length; | |
762 | L2TP_SKB_CB(skb)->expires = jiffies + | |
763 | (session->reorder_timeout ? session->reorder_timeout : HZ); | |
764 | ||
765 | /* Add packet to the session's receive queue. Reordering is done here, if | |
766 | * enabled. Saved L2TP protocol info is stored in skb->sb[]. | |
767 | */ | |
768 | if (L2TP_SKB_CB(skb)->has_seq) { | |
769 | if (session->reorder_timeout != 0) { | |
770 | /* Packet reordering enabled. Add skb to session's | |
771 | * reorder queue, in order of ns. | |
772 | */ | |
773 | l2tp_recv_queue_skb(session, skb); | |
774 | } else { | |
775 | /* Packet reordering disabled. Discard out-of-sequence | |
776 | * packets | |
777 | */ | |
778 | if (L2TP_SKB_CB(skb)->ns != session->nr) { | |
7b7c0719 | 779 | atomic_long_inc(&session->stats.rx_seq_discards); |
a4ca44fa JP |
780 | l2tp_dbg(session, L2TP_MSG_SEQ, |
781 | "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n", | |
782 | session->name, L2TP_SKB_CB(skb)->ns, | |
783 | L2TP_SKB_CB(skb)->length, session->nr, | |
784 | skb_queue_len(&session->reorder_q)); | |
fd558d18 JC |
785 | goto discard; |
786 | } | |
787 | skb_queue_tail(&session->reorder_q, skb); | |
788 | } | |
789 | } else { | |
790 | /* No sequence numbers. Add the skb to the tail of the | |
791 | * reorder queue. This ensures that it will be | |
792 | * delivered after all previous sequenced skbs. | |
793 | */ | |
794 | skb_queue_tail(&session->reorder_q, skb); | |
795 | } | |
796 | ||
797 | /* Try to dequeue as many skbs from reorder_q as we can. */ | |
798 | l2tp_recv_dequeue(session); | |
799 | ||
800 | l2tp_session_dec_refcount(session); | |
801 | ||
f7faffa3 | 802 | return; |
fd558d18 JC |
803 | |
804 | discard: | |
7b7c0719 | 805 | atomic_long_inc(&session->stats.rx_errors); |
fd558d18 JC |
806 | kfree_skb(skb); |
807 | ||
808 | if (session->deref) | |
809 | (*session->deref)(session); | |
810 | ||
811 | l2tp_session_dec_refcount(session); | |
f7faffa3 JC |
812 | } |
813 | EXPORT_SYMBOL(l2tp_recv_common); | |
814 | ||
48f72f92 TP |
815 | /* Drop skbs from the session's reorder_q |
816 | */ | |
817 | int l2tp_session_queue_purge(struct l2tp_session *session) | |
818 | { | |
819 | struct sk_buff *skb = NULL; | |
820 | BUG_ON(!session); | |
821 | BUG_ON(session->magic != L2TP_SESSION_MAGIC); | |
822 | while ((skb = skb_dequeue(&session->reorder_q))) { | |
823 | atomic_long_inc(&session->stats.rx_errors); | |
824 | kfree_skb(skb); | |
825 | if (session->deref) | |
826 | (*session->deref)(session); | |
827 | } | |
828 | return 0; | |
829 | } | |
830 | EXPORT_SYMBOL_GPL(l2tp_session_queue_purge); | |
831 | ||
f7faffa3 JC |
832 | /* Internal UDP receive frame. Do the real work of receiving an L2TP data frame |
833 | * here. The skb is not on a list when we get here. | |
834 | * Returns 0 if the packet was a data packet and was successfully passed on. | |
835 | * Returns 1 if the packet was not a good data packet and could not be | |
836 | * forwarded. All such packets are passed up to userspace to deal with. | |
837 | */ | |
fc130840 | 838 | static int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, |
839 | int (*payload_hook)(struct sk_buff *skb)) | |
f7faffa3 JC |
840 | { |
841 | struct l2tp_session *session = NULL; | |
842 | unsigned char *ptr, *optr; | |
843 | u16 hdrflags; | |
844 | u32 tunnel_id, session_id; | |
f7faffa3 JC |
845 | u16 version; |
846 | int length; | |
847 | ||
848 | if (tunnel->sock && l2tp_verify_udp_checksum(tunnel->sock, skb)) | |
849 | goto discard_bad_csum; | |
850 | ||
851 | /* UDP always verifies the packet length. */ | |
852 | __skb_pull(skb, sizeof(struct udphdr)); | |
853 | ||
854 | /* Short packet? */ | |
855 | if (!pskb_may_pull(skb, L2TP_HDR_SIZE_SEQ)) { | |
a4ca44fa JP |
856 | l2tp_info(tunnel, L2TP_MSG_DATA, |
857 | "%s: recv short packet (len=%d)\n", | |
858 | tunnel->name, skb->len); | |
f7faffa3 JC |
859 | goto error; |
860 | } | |
861 | ||
f7faffa3 JC |
862 | /* Trace packet contents, if enabled */ |
863 | if (tunnel->debug & L2TP_MSG_DATA) { | |
864 | length = min(32u, skb->len); | |
865 | if (!pskb_may_pull(skb, length)) | |
866 | goto error; | |
867 | ||
a4ca44fa JP |
868 | pr_debug("%s: recv\n", tunnel->name); |
869 | print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, skb->data, length); | |
f7faffa3 JC |
870 | } |
871 | ||
e50e705c ED |
872 | /* Point to L2TP header */ |
873 | optr = ptr = skb->data; | |
874 | ||
f7faffa3 JC |
875 | /* Get L2TP header flags */ |
876 | hdrflags = ntohs(*(__be16 *) ptr); | |
877 | ||
878 | /* Check protocol version */ | |
879 | version = hdrflags & L2TP_HDR_VER_MASK; | |
880 | if (version != tunnel->version) { | |
a4ca44fa JP |
881 | l2tp_info(tunnel, L2TP_MSG_DATA, |
882 | "%s: recv protocol version mismatch: got %d expected %d\n", | |
883 | tunnel->name, version, tunnel->version); | |
f7faffa3 JC |
884 | goto error; |
885 | } | |
886 | ||
887 | /* Get length of L2TP packet */ | |
888 | length = skb->len; | |
889 | ||
890 | /* If type is control packet, it is handled by userspace. */ | |
891 | if (hdrflags & L2TP_HDRFLAG_T) { | |
a4ca44fa JP |
892 | l2tp_dbg(tunnel, L2TP_MSG_DATA, |
893 | "%s: recv control packet, len=%d\n", | |
894 | tunnel->name, length); | |
f7faffa3 JC |
895 | goto error; |
896 | } | |
897 | ||
898 | /* Skip flags */ | |
899 | ptr += 2; | |
900 | ||
901 | if (tunnel->version == L2TP_HDR_VER_2) { | |
902 | /* If length is present, skip it */ | |
903 | if (hdrflags & L2TP_HDRFLAG_L) | |
904 | ptr += 2; | |
905 | ||
906 | /* Extract tunnel and session ID */ | |
907 | tunnel_id = ntohs(*(__be16 *) ptr); | |
908 | ptr += 2; | |
909 | session_id = ntohs(*(__be16 *) ptr); | |
910 | ptr += 2; | |
911 | } else { | |
912 | ptr += 2; /* skip reserved bits */ | |
913 | tunnel_id = tunnel->tunnel_id; | |
914 | session_id = ntohl(*(__be32 *) ptr); | |
915 | ptr += 4; | |
916 | } | |
917 | ||
918 | /* Find the session context */ | |
919 | session = l2tp_session_find(tunnel->l2tp_net, tunnel, session_id); | |
309795f4 | 920 | if (!session || !session->recv_skb) { |
f7faffa3 | 921 | /* Not found? Pass to userspace to deal with */ |
a4ca44fa JP |
922 | l2tp_info(tunnel, L2TP_MSG_DATA, |
923 | "%s: no session found (%u/%u). Passing up.\n", | |
924 | tunnel->name, tunnel_id, session_id); | |
f7faffa3 JC |
925 | goto error; |
926 | } | |
927 | ||
928 | l2tp_recv_common(session, skb, ptr, optr, hdrflags, length, payload_hook); | |
fd558d18 JC |
929 | |
930 | return 0; | |
931 | ||
932 | discard_bad_csum: | |
933 | LIMIT_NETDEBUG("%s: UDP: bad checksum\n", tunnel->name); | |
934 | UDP_INC_STATS_USER(tunnel->l2tp_net, UDP_MIB_INERRORS, 0); | |
7b7c0719 | 935 | atomic_long_inc(&tunnel->stats.rx_errors); |
fd558d18 JC |
936 | kfree_skb(skb); |
937 | ||
938 | return 0; | |
939 | ||
940 | error: | |
941 | /* Put UDP header back */ | |
942 | __skb_push(skb, sizeof(struct udphdr)); | |
943 | ||
944 | return 1; | |
945 | } | |
fd558d18 JC |
946 | |
947 | /* UDP encapsulation receive handler. See net/ipv4/udp.c. | |
948 | * Return codes: | |
949 | * 0 : success. | |
950 | * <0: error | |
951 | * >0: skb should be passed up to userspace as UDP. | |
952 | */ | |
953 | int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) | |
954 | { | |
955 | struct l2tp_tunnel *tunnel; | |
956 | ||
957 | tunnel = l2tp_sock_to_tunnel(sk); | |
958 | if (tunnel == NULL) | |
959 | goto pass_up; | |
960 | ||
a4ca44fa JP |
961 | l2tp_dbg(tunnel, L2TP_MSG_DATA, "%s: received %d bytes\n", |
962 | tunnel->name, skb->len); | |
fd558d18 JC |
963 | |
964 | if (l2tp_udp_recv_core(tunnel, skb, tunnel->recv_payload_hook)) | |
965 | goto pass_up_put; | |
966 | ||
967 | sock_put(sk); | |
968 | return 0; | |
969 | ||
970 | pass_up_put: | |
971 | sock_put(sk); | |
972 | pass_up: | |
973 | return 1; | |
974 | } | |
975 | EXPORT_SYMBOL_GPL(l2tp_udp_encap_recv); | |
976 | ||
977 | /************************************************************************ | |
978 | * Transmit handling | |
979 | ***********************************************************************/ | |
980 | ||
981 | /* Build an L2TP header for the session into the buffer provided. | |
982 | */ | |
f7faffa3 | 983 | static int l2tp_build_l2tpv2_header(struct l2tp_session *session, void *buf) |
fd558d18 | 984 | { |
f7faffa3 | 985 | struct l2tp_tunnel *tunnel = session->tunnel; |
fd558d18 | 986 | __be16 *bufp = buf; |
f7faffa3 | 987 | __be16 *optr = buf; |
fd558d18 JC |
988 | u16 flags = L2TP_HDR_VER_2; |
989 | u32 tunnel_id = tunnel->peer_tunnel_id; | |
990 | u32 session_id = session->peer_session_id; | |
991 | ||
992 | if (session->send_seq) | |
993 | flags |= L2TP_HDRFLAG_S; | |
994 | ||
995 | /* Setup L2TP header. */ | |
996 | *bufp++ = htons(flags); | |
997 | *bufp++ = htons(tunnel_id); | |
998 | *bufp++ = htons(session_id); | |
999 | if (session->send_seq) { | |
1000 | *bufp++ = htons(session->ns); | |
1001 | *bufp++ = 0; | |
1002 | session->ns++; | |
f7faffa3 | 1003 | session->ns &= 0xffff; |
a4ca44fa JP |
1004 | l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated ns to %u\n", |
1005 | session->name, session->ns); | |
fd558d18 | 1006 | } |
f7faffa3 JC |
1007 | |
1008 | return bufp - optr; | |
fd558d18 JC |
1009 | } |
1010 | ||
f7faffa3 | 1011 | static int l2tp_build_l2tpv3_header(struct l2tp_session *session, void *buf) |
fd558d18 | 1012 | { |
0d76751f | 1013 | struct l2tp_tunnel *tunnel = session->tunnel; |
f7faffa3 JC |
1014 | char *bufp = buf; |
1015 | char *optr = bufp; | |
f7faffa3 | 1016 | |
0d76751f JC |
1017 | /* Setup L2TP header. The header differs slightly for UDP and |
1018 | * IP encapsulations. For UDP, there is 4 bytes of flags. | |
1019 | */ | |
1020 | if (tunnel->encap == L2TP_ENCAPTYPE_UDP) { | |
1021 | u16 flags = L2TP_HDR_VER_3; | |
1022 | *((__be16 *) bufp) = htons(flags); | |
1023 | bufp += 2; | |
1024 | *((__be16 *) bufp) = 0; | |
1025 | bufp += 2; | |
1026 | } | |
1027 | ||
f7faffa3 JC |
1028 | *((__be32 *) bufp) = htonl(session->peer_session_id); |
1029 | bufp += 4; | |
1030 | if (session->cookie_len) { | |
1031 | memcpy(bufp, &session->cookie[0], session->cookie_len); | |
1032 | bufp += session->cookie_len; | |
1033 | } | |
1034 | if (session->l2specific_len) { | |
1035 | if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { | |
1036 | u32 l2h = 0; | |
1037 | if (session->send_seq) { | |
1038 | l2h = 0x40000000 | session->ns; | |
1039 | session->ns++; | |
1040 | session->ns &= 0xffffff; | |
a4ca44fa JP |
1041 | l2tp_dbg(session, L2TP_MSG_SEQ, |
1042 | "%s: updated ns to %u\n", | |
1043 | session->name, session->ns); | |
f7faffa3 JC |
1044 | } |
1045 | ||
1046 | *((__be32 *) bufp) = htonl(l2h); | |
1047 | } | |
1048 | bufp += session->l2specific_len; | |
1049 | } | |
1050 | if (session->offset) | |
1051 | bufp += session->offset; | |
fd558d18 | 1052 | |
f7faffa3 | 1053 | return bufp - optr; |
fd558d18 | 1054 | } |
fd558d18 | 1055 | |
fc130840 | 1056 | static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb, |
d9d8da80 | 1057 | struct flowi *fl, size_t data_len) |
fd558d18 JC |
1058 | { |
1059 | struct l2tp_tunnel *tunnel = session->tunnel; | |
1060 | unsigned int len = skb->len; | |
1061 | int error; | |
1062 | ||
1063 | /* Debug */ | |
1064 | if (session->send_seq) | |
a4ca44fa JP |
1065 | l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %Zd bytes, ns=%u\n", |
1066 | session->name, data_len, session->ns - 1); | |
fd558d18 | 1067 | else |
a4ca44fa JP |
1068 | l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %Zd bytes\n", |
1069 | session->name, data_len); | |
fd558d18 JC |
1070 | |
1071 | if (session->debug & L2TP_MSG_DATA) { | |
0d76751f JC |
1072 | int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
1073 | unsigned char *datap = skb->data + uhlen; | |
fd558d18 | 1074 | |
a4ca44fa JP |
1075 | pr_debug("%s: xmit\n", session->name); |
1076 | print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, | |
1077 | datap, min_t(size_t, 32, len - uhlen)); | |
fd558d18 JC |
1078 | } |
1079 | ||
1080 | /* Queue the packet to IP for output */ | |
4e15ed4d | 1081 | skb->local_df = 1; |
d2cf3361 | 1082 | #if IS_ENABLED(CONFIG_IPV6) |
bd83cd77 | 1083 | if (skb->sk->sk_family == PF_INET6 && !tunnel->v4mapped) |
d2cf3361 BL |
1084 | error = inet6_csk_xmit(skb, NULL); |
1085 | else | |
1086 | #endif | |
1087 | error = ip_queue_xmit(skb, fl); | |
fd558d18 JC |
1088 | |
1089 | /* Update stats */ | |
1090 | if (error >= 0) { | |
7b7c0719 TP |
1091 | atomic_long_inc(&tunnel->stats.tx_packets); |
1092 | atomic_long_add(len, &tunnel->stats.tx_bytes); | |
1093 | atomic_long_inc(&session->stats.tx_packets); | |
1094 | atomic_long_add(len, &session->stats.tx_bytes); | |
fd558d18 | 1095 | } else { |
7b7c0719 TP |
1096 | atomic_long_inc(&tunnel->stats.tx_errors); |
1097 | atomic_long_inc(&session->stats.tx_errors); | |
fd558d18 JC |
1098 | } |
1099 | ||
1100 | return 0; | |
1101 | } | |
fd558d18 JC |
1102 | |
1103 | /* Automatically called when the skb is freed. | |
1104 | */ | |
1105 | static void l2tp_sock_wfree(struct sk_buff *skb) | |
1106 | { | |
1107 | sock_put(skb->sk); | |
1108 | } | |
1109 | ||
1110 | /* For data skbs that we transmit, we associate with the tunnel socket | |
1111 | * but don't do accounting. | |
1112 | */ | |
1113 | static inline void l2tp_skb_set_owner_w(struct sk_buff *skb, struct sock *sk) | |
1114 | { | |
1115 | sock_hold(sk); | |
1116 | skb->sk = sk; | |
1117 | skb->destructor = l2tp_sock_wfree; | |
1118 | } | |
1119 | ||
d2cf3361 BL |
1120 | #if IS_ENABLED(CONFIG_IPV6) |
1121 | static void l2tp_xmit_ipv6_csum(struct sock *sk, struct sk_buff *skb, | |
1122 | int udp_len) | |
1123 | { | |
1124 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1125 | struct udphdr *uh = udp_hdr(skb); | |
1126 | ||
1127 | if (!skb_dst(skb) || !skb_dst(skb)->dev || | |
1128 | !(skb_dst(skb)->dev->features & NETIF_F_IPV6_CSUM)) { | |
1129 | __wsum csum = skb_checksum(skb, 0, udp_len, 0); | |
1130 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
1131 | uh->check = csum_ipv6_magic(&np->saddr, &np->daddr, udp_len, | |
1132 | IPPROTO_UDP, csum); | |
1133 | if (uh->check == 0) | |
1134 | uh->check = CSUM_MANGLED_0; | |
1135 | } else { | |
1136 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1137 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
1138 | skb->csum_offset = offsetof(struct udphdr, check); | |
1139 | uh->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, | |
1140 | udp_len, IPPROTO_UDP, 0); | |
1141 | } | |
1142 | } | |
1143 | #endif | |
1144 | ||
fd558d18 JC |
1145 | /* If caller requires the skb to have a ppp header, the header must be |
1146 | * inserted in the skb data before calling this function. | |
1147 | */ | |
1148 | int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len) | |
1149 | { | |
1150 | int data_len = skb->len; | |
0d76751f JC |
1151 | struct l2tp_tunnel *tunnel = session->tunnel; |
1152 | struct sock *sk = tunnel->sock; | |
d9d8da80 | 1153 | struct flowi *fl; |
fd558d18 | 1154 | struct udphdr *uh; |
fd558d18 JC |
1155 | struct inet_sock *inet; |
1156 | __wsum csum; | |
fd558d18 | 1157 | int headroom; |
0d76751f JC |
1158 | int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
1159 | int udp_len; | |
b8c84307 | 1160 | int ret = NET_XMIT_SUCCESS; |
fd558d18 JC |
1161 | |
1162 | /* Check that there's enough headroom in the skb to insert IP, | |
1163 | * UDP and L2TP headers. If not enough, expand it to | |
1164 | * make room. Adjust truesize. | |
1165 | */ | |
1166 | headroom = NET_SKB_PAD + sizeof(struct iphdr) + | |
0d76751f | 1167 | uhlen + hdr_len; |
835acf5d | 1168 | if (skb_cow_head(skb, headroom)) { |
b8c84307 ED |
1169 | kfree_skb(skb); |
1170 | return NET_XMIT_DROP; | |
835acf5d | 1171 | } |
fd558d18 | 1172 | |
fd558d18 | 1173 | skb_orphan(skb); |
fd558d18 | 1174 | /* Setup L2TP header */ |
f7faffa3 | 1175 | session->build_header(session, __skb_push(skb, hdr_len)); |
fd558d18 | 1176 | |
0d76751f | 1177 | /* Reset skb netfilter state */ |
fd558d18 JC |
1178 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
1179 | IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | | |
1180 | IPSKB_REROUTED); | |
1181 | nf_reset(skb); | |
1182 | ||
6af88da1 DM |
1183 | bh_lock_sock(sk); |
1184 | if (sock_owned_by_user(sk)) { | |
b8c84307 ED |
1185 | kfree_skb(skb); |
1186 | ret = NET_XMIT_DROP; | |
6af88da1 DM |
1187 | goto out_unlock; |
1188 | } | |
1189 | ||
fd558d18 JC |
1190 | /* Get routing info from the tunnel socket */ |
1191 | skb_dst_drop(skb); | |
71b1391a | 1192 | skb_dst_set(skb, dst_clone(__sk_dst_check(sk, 0))); |
fd558d18 | 1193 | |
d9d8da80 DM |
1194 | inet = inet_sk(sk); |
1195 | fl = &inet->cork.fl; | |
0d76751f JC |
1196 | switch (tunnel->encap) { |
1197 | case L2TP_ENCAPTYPE_UDP: | |
1198 | /* Setup UDP header */ | |
0d76751f JC |
1199 | __skb_push(skb, sizeof(*uh)); |
1200 | skb_reset_transport_header(skb); | |
1201 | uh = udp_hdr(skb); | |
1202 | uh->source = inet->inet_sport; | |
1203 | uh->dest = inet->inet_dport; | |
1204 | udp_len = uhlen + hdr_len + data_len; | |
1205 | uh->len = htons(udp_len); | |
1206 | uh->check = 0; | |
1207 | ||
1208 | /* Calculate UDP checksum if configured to do so */ | |
d2cf3361 | 1209 | #if IS_ENABLED(CONFIG_IPV6) |
bd83cd77 | 1210 | if (sk->sk_family == PF_INET6 && !tunnel->v4mapped) |
d2cf3361 BL |
1211 | l2tp_xmit_ipv6_csum(sk, skb, udp_len); |
1212 | else | |
1213 | #endif | |
0d76751f JC |
1214 | if (sk->sk_no_check == UDP_CSUM_NOXMIT) |
1215 | skb->ip_summed = CHECKSUM_NONE; | |
1216 | else if ((skb_dst(skb) && skb_dst(skb)->dev) && | |
1217 | (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) { | |
1218 | skb->ip_summed = CHECKSUM_COMPLETE; | |
1219 | csum = skb_checksum(skb, 0, udp_len, 0); | |
1220 | uh->check = csum_tcpudp_magic(inet->inet_saddr, | |
1221 | inet->inet_daddr, | |
1222 | udp_len, IPPROTO_UDP, csum); | |
1223 | if (uh->check == 0) | |
1224 | uh->check = CSUM_MANGLED_0; | |
1225 | } else { | |
1226 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1227 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
1228 | skb->csum_offset = offsetof(struct udphdr, check); | |
1229 | uh->check = ~csum_tcpudp_magic(inet->inet_saddr, | |
1230 | inet->inet_daddr, | |
1231 | udp_len, IPPROTO_UDP, 0); | |
1232 | } | |
1233 | break; | |
1234 | ||
1235 | case L2TP_ENCAPTYPE_IP: | |
1236 | break; | |
fd558d18 JC |
1237 | } |
1238 | ||
0d76751f JC |
1239 | l2tp_skb_set_owner_w(skb, sk); |
1240 | ||
d9d8da80 | 1241 | l2tp_xmit_core(session, skb, fl, data_len); |
6af88da1 DM |
1242 | out_unlock: |
1243 | bh_unlock_sock(sk); | |
fd558d18 | 1244 | |
b8c84307 | 1245 | return ret; |
fd558d18 JC |
1246 | } |
1247 | EXPORT_SYMBOL_GPL(l2tp_xmit_skb); | |
1248 | ||
1249 | /***************************************************************************** | |
1250 | * Tinnel and session create/destroy. | |
1251 | *****************************************************************************/ | |
1252 | ||
1253 | /* Tunnel socket destruct hook. | |
1254 | * The tunnel context is deleted only when all session sockets have been | |
1255 | * closed. | |
1256 | */ | |
fc130840 | 1257 | static void l2tp_tunnel_destruct(struct sock *sk) |
fd558d18 | 1258 | { |
d980ed62 | 1259 | struct l2tp_tunnel *tunnel = l2tp_tunnel(sk); |
f8ccac0e | 1260 | struct l2tp_net *pn; |
fd558d18 | 1261 | |
fd558d18 JC |
1262 | if (tunnel == NULL) |
1263 | goto end; | |
1264 | ||
a4ca44fa | 1265 | l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing...\n", tunnel->name); |
fd558d18 | 1266 | |
fd558d18 | 1267 | |
f8ccac0e | 1268 | /* Disable udp encapsulation */ |
0d76751f JC |
1269 | switch (tunnel->encap) { |
1270 | case L2TP_ENCAPTYPE_UDP: | |
1271 | /* No longer an encapsulation socket. See net/ipv4/udp.c */ | |
1272 | (udp_sk(sk))->encap_type = 0; | |
1273 | (udp_sk(sk))->encap_rcv = NULL; | |
9980d001 | 1274 | (udp_sk(sk))->encap_destroy = NULL; |
0d76751f JC |
1275 | break; |
1276 | case L2TP_ENCAPTYPE_IP: | |
1277 | break; | |
1278 | } | |
fd558d18 JC |
1279 | |
1280 | /* Remove hooks into tunnel socket */ | |
fd558d18 JC |
1281 | sk->sk_destruct = tunnel->old_sk_destruct; |
1282 | sk->sk_user_data = NULL; | |
f8ccac0e | 1283 | tunnel->sock = NULL; |
fd558d18 | 1284 | |
f8ccac0e TP |
1285 | /* Remove the tunnel struct from the tunnel list */ |
1286 | pn = l2tp_pernet(tunnel->l2tp_net); | |
1287 | spin_lock_bh(&pn->l2tp_tunnel_list_lock); | |
1288 | list_del_rcu(&tunnel->list); | |
1289 | spin_unlock_bh(&pn->l2tp_tunnel_list_lock); | |
1290 | atomic_dec(&l2tp_tunnel_count); | |
fd558d18 | 1291 | |
f8ccac0e | 1292 | l2tp_tunnel_closeall(tunnel); |
fd558d18 JC |
1293 | l2tp_tunnel_dec_refcount(tunnel); |
1294 | ||
f8ccac0e TP |
1295 | /* Call the original destructor */ |
1296 | if (sk->sk_destruct) | |
1297 | (*sk->sk_destruct)(sk); | |
fd558d18 JC |
1298 | end: |
1299 | return; | |
1300 | } | |
fd558d18 JC |
1301 | |
1302 | /* When the tunnel is closed, all the attached sessions need to go too. | |
1303 | */ | |
e34f4c70 | 1304 | void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel) |
fd558d18 JC |
1305 | { |
1306 | int hash; | |
1307 | struct hlist_node *walk; | |
1308 | struct hlist_node *tmp; | |
1309 | struct l2tp_session *session; | |
1310 | ||
1311 | BUG_ON(tunnel == NULL); | |
1312 | ||
a4ca44fa JP |
1313 | l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing all sessions...\n", |
1314 | tunnel->name); | |
fd558d18 JC |
1315 | |
1316 | write_lock_bh(&tunnel->hlist_lock); | |
1317 | for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { | |
1318 | again: | |
1319 | hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { | |
1320 | session = hlist_entry(walk, struct l2tp_session, hlist); | |
1321 | ||
a4ca44fa JP |
1322 | l2tp_info(session, L2TP_MSG_CONTROL, |
1323 | "%s: closing session\n", session->name); | |
fd558d18 JC |
1324 | |
1325 | hlist_del_init(&session->hlist); | |
1326 | ||
fd558d18 JC |
1327 | if (session->ref != NULL) |
1328 | (*session->ref)(session); | |
1329 | ||
1330 | write_unlock_bh(&tunnel->hlist_lock); | |
1331 | ||
f6e16b29 | 1332 | __l2tp_session_unhash(session); |
4c6e2fd3 TP |
1333 | l2tp_session_queue_purge(session); |
1334 | ||
fd558d18 JC |
1335 | if (session->session_close != NULL) |
1336 | (*session->session_close)(session); | |
1337 | ||
1338 | if (session->deref != NULL) | |
1339 | (*session->deref)(session); | |
1340 | ||
9980d001 TP |
1341 | l2tp_session_dec_refcount(session); |
1342 | ||
fd558d18 JC |
1343 | write_lock_bh(&tunnel->hlist_lock); |
1344 | ||
1345 | /* Now restart from the beginning of this hash | |
1346 | * chain. We always remove a session from the | |
1347 | * list so we are guaranteed to make forward | |
1348 | * progress. | |
1349 | */ | |
1350 | goto again; | |
1351 | } | |
1352 | } | |
1353 | write_unlock_bh(&tunnel->hlist_lock); | |
1354 | } | |
e34f4c70 | 1355 | EXPORT_SYMBOL_GPL(l2tp_tunnel_closeall); |
fd558d18 | 1356 | |
9980d001 TP |
1357 | /* Tunnel socket destroy hook for UDP encapsulation */ |
1358 | static void l2tp_udp_encap_destroy(struct sock *sk) | |
1359 | { | |
1360 | struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); | |
1361 | if (tunnel) { | |
1362 | l2tp_tunnel_closeall(tunnel); | |
1363 | sock_put(sk); | |
1364 | } | |
1365 | } | |
1366 | ||
fd558d18 JC |
1367 | /* Really kill the tunnel. |
1368 | * Come here only when all sessions have been cleared from the tunnel. | |
1369 | */ | |
fc130840 | 1370 | static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel) |
fd558d18 | 1371 | { |
fd558d18 JC |
1372 | BUG_ON(atomic_read(&tunnel->ref_count) != 0); |
1373 | BUG_ON(tunnel->sock != NULL); | |
a4ca44fa | 1374 | l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: free...\n", tunnel->name); |
99469c32 | 1375 | kfree_rcu(tunnel, rcu); |
f8ccac0e | 1376 | } |
fd558d18 | 1377 | |
f8ccac0e TP |
1378 | /* Workqueue tunnel deletion function */ |
1379 | static void l2tp_tunnel_del_work(struct work_struct *work) | |
1380 | { | |
1381 | struct l2tp_tunnel *tunnel = NULL; | |
1382 | struct socket *sock = NULL; | |
1383 | struct sock *sk = NULL; | |
1384 | ||
1385 | tunnel = container_of(work, struct l2tp_tunnel, del_work); | |
1386 | sk = l2tp_tunnel_sock_lookup(tunnel); | |
1387 | if (!sk) | |
9bbb3d0d | 1388 | goto out; |
f8ccac0e TP |
1389 | |
1390 | sock = sk->sk_socket; | |
f8ccac0e | 1391 | |
02d13ed5 TP |
1392 | /* If the tunnel socket was created by userspace, then go through the |
1393 | * inet layer to shut the socket down, and let userspace close it. | |
1394 | * Otherwise, if we created the socket directly within the kernel, use | |
1395 | * the sk API to release it here. | |
167eb17e TP |
1396 | * In either case the tunnel resources are freed in the socket |
1397 | * destructor when the tunnel socket goes away. | |
f8ccac0e | 1398 | */ |
02d13ed5 TP |
1399 | if (tunnel->fd >= 0) { |
1400 | if (sock) | |
1401 | inet_shutdown(sock, 2); | |
167eb17e | 1402 | } else { |
02d13ed5 TP |
1403 | if (sock) |
1404 | kernel_sock_shutdown(sock, SHUT_RDWR); | |
1405 | sk_release_kernel(sk); | |
167eb17e | 1406 | } |
f8ccac0e TP |
1407 | |
1408 | l2tp_tunnel_sock_put(sk); | |
9bbb3d0d AC |
1409 | out: |
1410 | l2tp_tunnel_dec_refcount(tunnel); | |
fd558d18 | 1411 | } |
fd558d18 | 1412 | |
789a4a2c JC |
1413 | /* Create a socket for the tunnel, if one isn't set up by |
1414 | * userspace. This is used for static tunnels where there is no | |
1415 | * managing L2TP daemon. | |
167eb17e TP |
1416 | * |
1417 | * Since we don't want these sockets to keep a namespace alive by | |
1418 | * themselves, we drop the socket's namespace refcount after creation. | |
1419 | * These sockets are freed when the namespace exits using the pernet | |
1420 | * exit hook. | |
789a4a2c | 1421 | */ |
167eb17e TP |
1422 | static int l2tp_tunnel_sock_create(struct net *net, |
1423 | u32 tunnel_id, | |
1424 | u32 peer_tunnel_id, | |
1425 | struct l2tp_tunnel_cfg *cfg, | |
1426 | struct socket **sockp) | |
789a4a2c JC |
1427 | { |
1428 | int err = -EINVAL; | |
167eb17e TP |
1429 | struct socket *sock = NULL; |
1430 | struct sockaddr_in udp_addr = {0}; | |
1431 | struct sockaddr_l2tpip ip_addr = {0}; | |
f9bac8df | 1432 | #if IS_ENABLED(CONFIG_IPV6) |
167eb17e TP |
1433 | struct sockaddr_in6 udp6_addr = {0}; |
1434 | struct sockaddr_l2tpip6 ip6_addr = {0}; | |
f9bac8df | 1435 | #endif |
789a4a2c JC |
1436 | |
1437 | switch (cfg->encap) { | |
1438 | case L2TP_ENCAPTYPE_UDP: | |
f9bac8df CE |
1439 | #if IS_ENABLED(CONFIG_IPV6) |
1440 | if (cfg->local_ip6 && cfg->peer_ip6) { | |
167eb17e | 1441 | err = sock_create_kern(AF_INET6, SOCK_DGRAM, 0, &sock); |
f9bac8df CE |
1442 | if (err < 0) |
1443 | goto out; | |
789a4a2c | 1444 | |
167eb17e | 1445 | sk_change_net(sock->sk, net); |
789a4a2c | 1446 | |
f9bac8df CE |
1447 | udp6_addr.sin6_family = AF_INET6; |
1448 | memcpy(&udp6_addr.sin6_addr, cfg->local_ip6, | |
1449 | sizeof(udp6_addr.sin6_addr)); | |
1450 | udp6_addr.sin6_port = htons(cfg->local_udp_port); | |
1451 | err = kernel_bind(sock, (struct sockaddr *) &udp6_addr, | |
1452 | sizeof(udp6_addr)); | |
1453 | if (err < 0) | |
1454 | goto out; | |
789a4a2c | 1455 | |
f9bac8df CE |
1456 | udp6_addr.sin6_family = AF_INET6; |
1457 | memcpy(&udp6_addr.sin6_addr, cfg->peer_ip6, | |
1458 | sizeof(udp6_addr.sin6_addr)); | |
1459 | udp6_addr.sin6_port = htons(cfg->peer_udp_port); | |
1460 | err = kernel_connect(sock, | |
1461 | (struct sockaddr *) &udp6_addr, | |
1462 | sizeof(udp6_addr), 0); | |
1463 | if (err < 0) | |
1464 | goto out; | |
1465 | } else | |
1466 | #endif | |
1467 | { | |
167eb17e | 1468 | err = sock_create_kern(AF_INET, SOCK_DGRAM, 0, &sock); |
f9bac8df CE |
1469 | if (err < 0) |
1470 | goto out; | |
1471 | ||
167eb17e | 1472 | sk_change_net(sock->sk, net); |
f9bac8df | 1473 | |
f9bac8df CE |
1474 | udp_addr.sin_family = AF_INET; |
1475 | udp_addr.sin_addr = cfg->local_ip; | |
1476 | udp_addr.sin_port = htons(cfg->local_udp_port); | |
1477 | err = kernel_bind(sock, (struct sockaddr *) &udp_addr, | |
1478 | sizeof(udp_addr)); | |
1479 | if (err < 0) | |
1480 | goto out; | |
1481 | ||
1482 | udp_addr.sin_family = AF_INET; | |
1483 | udp_addr.sin_addr = cfg->peer_ip; | |
1484 | udp_addr.sin_port = htons(cfg->peer_udp_port); | |
1485 | err = kernel_connect(sock, | |
1486 | (struct sockaddr *) &udp_addr, | |
1487 | sizeof(udp_addr), 0); | |
1488 | if (err < 0) | |
1489 | goto out; | |
1490 | } | |
789a4a2c JC |
1491 | |
1492 | if (!cfg->use_udp_checksums) | |
1493 | sock->sk->sk_no_check = UDP_CSUM_NOXMIT; | |
1494 | ||
1495 | break; | |
1496 | ||
1497 | case L2TP_ENCAPTYPE_IP: | |
f9bac8df CE |
1498 | #if IS_ENABLED(CONFIG_IPV6) |
1499 | if (cfg->local_ip6 && cfg->peer_ip6) { | |
167eb17e TP |
1500 | err = sock_create_kern(AF_INET6, SOCK_DGRAM, |
1501 | IPPROTO_L2TP, &sock); | |
5dac94e1 JC |
1502 | if (err < 0) |
1503 | goto out; | |
789a4a2c | 1504 | |
167eb17e | 1505 | sk_change_net(sock->sk, net); |
789a4a2c | 1506 | |
5dac94e1 JC |
1507 | ip6_addr.l2tp_family = AF_INET6; |
1508 | memcpy(&ip6_addr.l2tp_addr, cfg->local_ip6, | |
1509 | sizeof(ip6_addr.l2tp_addr)); | |
1510 | ip6_addr.l2tp_conn_id = tunnel_id; | |
1511 | err = kernel_bind(sock, (struct sockaddr *) &ip6_addr, | |
1512 | sizeof(ip6_addr)); | |
1513 | if (err < 0) | |
1514 | goto out; | |
789a4a2c | 1515 | |
5dac94e1 JC |
1516 | ip6_addr.l2tp_family = AF_INET6; |
1517 | memcpy(&ip6_addr.l2tp_addr, cfg->peer_ip6, | |
1518 | sizeof(ip6_addr.l2tp_addr)); | |
1519 | ip6_addr.l2tp_conn_id = peer_tunnel_id; | |
1520 | err = kernel_connect(sock, | |
1521 | (struct sockaddr *) &ip6_addr, | |
1522 | sizeof(ip6_addr), 0); | |
1523 | if (err < 0) | |
1524 | goto out; | |
1525 | } else | |
1526 | #endif | |
1527 | { | |
167eb17e TP |
1528 | err = sock_create_kern(AF_INET, SOCK_DGRAM, |
1529 | IPPROTO_L2TP, &sock); | |
5dac94e1 JC |
1530 | if (err < 0) |
1531 | goto out; | |
789a4a2c | 1532 | |
167eb17e | 1533 | sk_change_net(sock->sk, net); |
5dac94e1 | 1534 | |
5dac94e1 JC |
1535 | ip_addr.l2tp_family = AF_INET; |
1536 | ip_addr.l2tp_addr = cfg->local_ip; | |
1537 | ip_addr.l2tp_conn_id = tunnel_id; | |
1538 | err = kernel_bind(sock, (struct sockaddr *) &ip_addr, | |
1539 | sizeof(ip_addr)); | |
1540 | if (err < 0) | |
1541 | goto out; | |
1542 | ||
1543 | ip_addr.l2tp_family = AF_INET; | |
1544 | ip_addr.l2tp_addr = cfg->peer_ip; | |
1545 | ip_addr.l2tp_conn_id = peer_tunnel_id; | |
1546 | err = kernel_connect(sock, (struct sockaddr *) &ip_addr, | |
1547 | sizeof(ip_addr), 0); | |
1548 | if (err < 0) | |
1549 | goto out; | |
1550 | } | |
789a4a2c JC |
1551 | break; |
1552 | ||
1553 | default: | |
1554 | goto out; | |
1555 | } | |
1556 | ||
1557 | out: | |
167eb17e | 1558 | *sockp = sock; |
789a4a2c | 1559 | if ((err < 0) && sock) { |
167eb17e TP |
1560 | kernel_sock_shutdown(sock, SHUT_RDWR); |
1561 | sk_release_kernel(sock->sk); | |
789a4a2c JC |
1562 | *sockp = NULL; |
1563 | } | |
1564 | ||
1565 | return err; | |
1566 | } | |
1567 | ||
37159ef2 ED |
1568 | static struct lock_class_key l2tp_socket_class; |
1569 | ||
fd558d18 JC |
1570 | int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg, struct l2tp_tunnel **tunnelp) |
1571 | { | |
1572 | struct l2tp_tunnel *tunnel = NULL; | |
1573 | int err; | |
1574 | struct socket *sock = NULL; | |
1575 | struct sock *sk = NULL; | |
1576 | struct l2tp_net *pn; | |
0d76751f | 1577 | enum l2tp_encap_type encap = L2TP_ENCAPTYPE_UDP; |
fd558d18 JC |
1578 | |
1579 | /* Get the tunnel socket from the fd, which was opened by | |
789a4a2c JC |
1580 | * the userspace L2TP daemon. If not specified, create a |
1581 | * kernel socket. | |
fd558d18 | 1582 | */ |
789a4a2c | 1583 | if (fd < 0) { |
167eb17e TP |
1584 | err = l2tp_tunnel_sock_create(net, tunnel_id, peer_tunnel_id, |
1585 | cfg, &sock); | |
789a4a2c JC |
1586 | if (err < 0) |
1587 | goto err; | |
1588 | } else { | |
789a4a2c JC |
1589 | sock = sockfd_lookup(fd, &err); |
1590 | if (!sock) { | |
cbb95e0c | 1591 | pr_err("tunl %u: sockfd_lookup(fd=%d) returned %d\n", |
789a4a2c | 1592 | tunnel_id, fd, err); |
cbb95e0c TP |
1593 | err = -EBADF; |
1594 | goto err; | |
1595 | } | |
1596 | ||
1597 | /* Reject namespace mismatches */ | |
1598 | if (!net_eq(sock_net(sock->sk), net)) { | |
1599 | pr_err("tunl %u: netns mismatch\n", tunnel_id); | |
1600 | err = -EINVAL; | |
789a4a2c JC |
1601 | goto err; |
1602 | } | |
fd558d18 JC |
1603 | } |
1604 | ||
1605 | sk = sock->sk; | |
1606 | ||
0d76751f JC |
1607 | if (cfg != NULL) |
1608 | encap = cfg->encap; | |
1609 | ||
fd558d18 | 1610 | /* Quick sanity checks */ |
0d76751f JC |
1611 | switch (encap) { |
1612 | case L2TP_ENCAPTYPE_UDP: | |
1613 | err = -EPROTONOSUPPORT; | |
1614 | if (sk->sk_protocol != IPPROTO_UDP) { | |
a4ca44fa | 1615 | pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", |
0d76751f JC |
1616 | tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP); |
1617 | goto err; | |
1618 | } | |
1619 | break; | |
1620 | case L2TP_ENCAPTYPE_IP: | |
1621 | err = -EPROTONOSUPPORT; | |
1622 | if (sk->sk_protocol != IPPROTO_L2TP) { | |
a4ca44fa | 1623 | pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", |
0d76751f JC |
1624 | tunnel_id, fd, sk->sk_protocol, IPPROTO_L2TP); |
1625 | goto err; | |
1626 | } | |
1627 | break; | |
fd558d18 JC |
1628 | } |
1629 | ||
1630 | /* Check if this socket has already been prepped */ | |
d980ed62 | 1631 | tunnel = l2tp_tunnel(sk); |
fd558d18 JC |
1632 | if (tunnel != NULL) { |
1633 | /* This socket has already been prepped */ | |
1634 | err = -EBUSY; | |
1635 | goto err; | |
1636 | } | |
1637 | ||
fd558d18 JC |
1638 | tunnel = kzalloc(sizeof(struct l2tp_tunnel), GFP_KERNEL); |
1639 | if (tunnel == NULL) { | |
1640 | err = -ENOMEM; | |
1641 | goto err; | |
1642 | } | |
1643 | ||
1644 | tunnel->version = version; | |
1645 | tunnel->tunnel_id = tunnel_id; | |
1646 | tunnel->peer_tunnel_id = peer_tunnel_id; | |
1647 | tunnel->debug = L2TP_DEFAULT_DEBUG_FLAGS; | |
1648 | ||
1649 | tunnel->magic = L2TP_TUNNEL_MAGIC; | |
1650 | sprintf(&tunnel->name[0], "tunl %u", tunnel_id); | |
1651 | rwlock_init(&tunnel->hlist_lock); | |
1652 | ||
1653 | /* The net we belong to */ | |
1654 | tunnel->l2tp_net = net; | |
1655 | pn = l2tp_pernet(net); | |
1656 | ||
0d76751f | 1657 | if (cfg != NULL) |
fd558d18 JC |
1658 | tunnel->debug = cfg->debug; |
1659 | ||
bd83cd77 FC |
1660 | #if IS_ENABLED(CONFIG_IPV6) |
1661 | if (sk->sk_family == PF_INET6) { | |
1662 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1663 | ||
1664 | if (ipv6_addr_v4mapped(&np->saddr) && | |
1665 | ipv6_addr_v4mapped(&np->daddr)) { | |
1666 | struct inet_sock *inet = inet_sk(sk); | |
1667 | ||
1668 | tunnel->v4mapped = true; | |
1669 | inet->inet_saddr = np->saddr.s6_addr32[3]; | |
1670 | inet->inet_rcv_saddr = np->rcv_saddr.s6_addr32[3]; | |
1671 | inet->inet_daddr = np->daddr.s6_addr32[3]; | |
1672 | } else { | |
1673 | tunnel->v4mapped = false; | |
1674 | } | |
1675 | } | |
1676 | #endif | |
1677 | ||
fd558d18 | 1678 | /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ |
0d76751f JC |
1679 | tunnel->encap = encap; |
1680 | if (encap == L2TP_ENCAPTYPE_UDP) { | |
1681 | /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ | |
1682 | udp_sk(sk)->encap_type = UDP_ENCAP_L2TPINUDP; | |
1683 | udp_sk(sk)->encap_rcv = l2tp_udp_encap_recv; | |
9980d001 | 1684 | udp_sk(sk)->encap_destroy = l2tp_udp_encap_destroy; |
d2cf3361 | 1685 | #if IS_ENABLED(CONFIG_IPV6) |
bd83cd77 | 1686 | if (sk->sk_family == PF_INET6 && !tunnel->v4mapped) |
d2cf3361 BL |
1687 | udpv6_encap_enable(); |
1688 | else | |
1689 | #endif | |
447167bf | 1690 | udp_encap_enable(); |
0d76751f | 1691 | } |
fd558d18 JC |
1692 | |
1693 | sk->sk_user_data = tunnel; | |
1694 | ||
1695 | /* Hook on the tunnel socket destructor so that we can cleanup | |
1696 | * if the tunnel socket goes away. | |
1697 | */ | |
1698 | tunnel->old_sk_destruct = sk->sk_destruct; | |
1699 | sk->sk_destruct = &l2tp_tunnel_destruct; | |
1700 | tunnel->sock = sk; | |
80d84ef3 | 1701 | tunnel->fd = fd; |
37159ef2 ED |
1702 | lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class, "l2tp_sock"); |
1703 | ||
fd558d18 JC |
1704 | sk->sk_allocation = GFP_ATOMIC; |
1705 | ||
f8ccac0e TP |
1706 | /* Init delete workqueue struct */ |
1707 | INIT_WORK(&tunnel->del_work, l2tp_tunnel_del_work); | |
1708 | ||
fd558d18 JC |
1709 | /* Add tunnel to our list */ |
1710 | INIT_LIST_HEAD(&tunnel->list); | |
fd558d18 JC |
1711 | atomic_inc(&l2tp_tunnel_count); |
1712 | ||
1713 | /* Bump the reference count. The tunnel context is deleted | |
1769192a | 1714 | * only when this drops to zero. Must be done before list insertion |
fd558d18 JC |
1715 | */ |
1716 | l2tp_tunnel_inc_refcount(tunnel); | |
1769192a ED |
1717 | spin_lock_bh(&pn->l2tp_tunnel_list_lock); |
1718 | list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list); | |
1719 | spin_unlock_bh(&pn->l2tp_tunnel_list_lock); | |
fd558d18 JC |
1720 | |
1721 | err = 0; | |
1722 | err: | |
1723 | if (tunnelp) | |
1724 | *tunnelp = tunnel; | |
1725 | ||
789a4a2c JC |
1726 | /* If tunnel's socket was created by the kernel, it doesn't |
1727 | * have a file. | |
1728 | */ | |
1729 | if (sock && sock->file) | |
fd558d18 JC |
1730 | sockfd_put(sock); |
1731 | ||
1732 | return err; | |
1733 | } | |
1734 | EXPORT_SYMBOL_GPL(l2tp_tunnel_create); | |
1735 | ||
309795f4 JC |
1736 | /* This function is used by the netlink TUNNEL_DELETE command. |
1737 | */ | |
1738 | int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) | |
1739 | { | |
9bbb3d0d | 1740 | l2tp_tunnel_inc_refcount(tunnel); |
2b551c6e | 1741 | l2tp_tunnel_closeall(tunnel); |
9bbb3d0d AC |
1742 | if (false == queue_work(l2tp_wq, &tunnel->del_work)) { |
1743 | l2tp_tunnel_dec_refcount(tunnel); | |
1744 | return 1; | |
1745 | } | |
1746 | return 0; | |
309795f4 JC |
1747 | } |
1748 | EXPORT_SYMBOL_GPL(l2tp_tunnel_delete); | |
1749 | ||
fd558d18 JC |
1750 | /* Really kill the session. |
1751 | */ | |
1752 | void l2tp_session_free(struct l2tp_session *session) | |
1753 | { | |
f6e16b29 | 1754 | struct l2tp_tunnel *tunnel = session->tunnel; |
fd558d18 JC |
1755 | |
1756 | BUG_ON(atomic_read(&session->ref_count) != 0); | |
1757 | ||
f6e16b29 | 1758 | if (tunnel) { |
fd558d18 | 1759 | BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); |
f6e16b29 TP |
1760 | if (session->session_id != 0) |
1761 | atomic_dec(&l2tp_session_count); | |
1762 | sock_put(tunnel->sock); | |
1763 | session->tunnel = NULL; | |
1764 | l2tp_tunnel_dec_refcount(tunnel); | |
1765 | } | |
1766 | ||
1767 | kfree(session); | |
1768 | ||
1769 | return; | |
1770 | } | |
1771 | EXPORT_SYMBOL_GPL(l2tp_session_free); | |
1772 | ||
1773 | /* Remove an l2tp session from l2tp_core's hash lists. | |
1774 | * Provides a tidyup interface for pseudowire code which can't just route all | |
1775 | * shutdown via. l2tp_session_delete and a pseudowire-specific session_close | |
1776 | * callback. | |
1777 | */ | |
1778 | void __l2tp_session_unhash(struct l2tp_session *session) | |
1779 | { | |
1780 | struct l2tp_tunnel *tunnel = session->tunnel; | |
fd558d18 | 1781 | |
f6e16b29 TP |
1782 | /* Remove the session from core hashes */ |
1783 | if (tunnel) { | |
1784 | /* Remove from the per-tunnel hash */ | |
fd558d18 JC |
1785 | write_lock_bh(&tunnel->hlist_lock); |
1786 | hlist_del_init(&session->hlist); | |
1787 | write_unlock_bh(&tunnel->hlist_lock); | |
1788 | ||
f6e16b29 | 1789 | /* For L2TPv3 we have a per-net hash: remove from there, too */ |
f7faffa3 JC |
1790 | if (tunnel->version != L2TP_HDR_VER_2) { |
1791 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); | |
e02d494d JC |
1792 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
1793 | hlist_del_init_rcu(&session->global_hlist); | |
1794 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); | |
1795 | synchronize_rcu(); | |
f7faffa3 | 1796 | } |
fd558d18 | 1797 | } |
fd558d18 | 1798 | } |
f6e16b29 | 1799 | EXPORT_SYMBOL_GPL(__l2tp_session_unhash); |
fd558d18 | 1800 | |
309795f4 JC |
1801 | /* This function is used by the netlink SESSION_DELETE command and by |
1802 | pseudowire modules. | |
1803 | */ | |
1804 | int l2tp_session_delete(struct l2tp_session *session) | |
1805 | { | |
f6e16b29 TP |
1806 | if (session->ref) |
1807 | (*session->ref)(session); | |
1808 | __l2tp_session_unhash(session); | |
4c6e2fd3 | 1809 | l2tp_session_queue_purge(session); |
309795f4 JC |
1810 | if (session->session_close != NULL) |
1811 | (*session->session_close)(session); | |
f6e16b29 | 1812 | if (session->deref) |
1b7c92b9 | 1813 | (*session->deref)(session); |
309795f4 | 1814 | l2tp_session_dec_refcount(session); |
309795f4 JC |
1815 | return 0; |
1816 | } | |
1817 | EXPORT_SYMBOL_GPL(l2tp_session_delete); | |
1818 | ||
f7faffa3 JC |
1819 | /* We come here whenever a session's send_seq, cookie_len or |
1820 | * l2specific_len parameters are set. | |
1821 | */ | |
fc130840 | 1822 | static void l2tp_session_set_header_len(struct l2tp_session *session, int version) |
f7faffa3 JC |
1823 | { |
1824 | if (version == L2TP_HDR_VER_2) { | |
1825 | session->hdr_len = 6; | |
1826 | if (session->send_seq) | |
1827 | session->hdr_len += 4; | |
1828 | } else { | |
0d76751f JC |
1829 | session->hdr_len = 4 + session->cookie_len + session->l2specific_len + session->offset; |
1830 | if (session->tunnel->encap == L2TP_ENCAPTYPE_UDP) | |
1831 | session->hdr_len += 4; | |
f7faffa3 JC |
1832 | } |
1833 | ||
1834 | } | |
f7faffa3 | 1835 | |
fd558d18 JC |
1836 | struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunnel, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg) |
1837 | { | |
1838 | struct l2tp_session *session; | |
1839 | ||
1840 | session = kzalloc(sizeof(struct l2tp_session) + priv_size, GFP_KERNEL); | |
1841 | if (session != NULL) { | |
1842 | session->magic = L2TP_SESSION_MAGIC; | |
1843 | session->tunnel = tunnel; | |
1844 | ||
1845 | session->session_id = session_id; | |
1846 | session->peer_session_id = peer_session_id; | |
d301e325 | 1847 | session->nr = 0; |
fd558d18 JC |
1848 | |
1849 | sprintf(&session->name[0], "sess %u/%u", | |
1850 | tunnel->tunnel_id, session->session_id); | |
1851 | ||
1852 | skb_queue_head_init(&session->reorder_q); | |
1853 | ||
1854 | INIT_HLIST_NODE(&session->hlist); | |
f7faffa3 | 1855 | INIT_HLIST_NODE(&session->global_hlist); |
fd558d18 JC |
1856 | |
1857 | /* Inherit debug options from tunnel */ | |
1858 | session->debug = tunnel->debug; | |
1859 | ||
1860 | if (cfg) { | |
f7faffa3 | 1861 | session->pwtype = cfg->pw_type; |
fd558d18 | 1862 | session->debug = cfg->debug; |
fd558d18 JC |
1863 | session->mtu = cfg->mtu; |
1864 | session->mru = cfg->mru; | |
1865 | session->send_seq = cfg->send_seq; | |
1866 | session->recv_seq = cfg->recv_seq; | |
1867 | session->lns_mode = cfg->lns_mode; | |
f7faffa3 JC |
1868 | session->reorder_timeout = cfg->reorder_timeout; |
1869 | session->offset = cfg->offset; | |
1870 | session->l2specific_type = cfg->l2specific_type; | |
1871 | session->l2specific_len = cfg->l2specific_len; | |
1872 | session->cookie_len = cfg->cookie_len; | |
1873 | memcpy(&session->cookie[0], &cfg->cookie[0], cfg->cookie_len); | |
1874 | session->peer_cookie_len = cfg->peer_cookie_len; | |
1875 | memcpy(&session->peer_cookie[0], &cfg->peer_cookie[0], cfg->peer_cookie_len); | |
fd558d18 JC |
1876 | } |
1877 | ||
f7faffa3 JC |
1878 | if (tunnel->version == L2TP_HDR_VER_2) |
1879 | session->build_header = l2tp_build_l2tpv2_header; | |
1880 | else | |
1881 | session->build_header = l2tp_build_l2tpv3_header; | |
1882 | ||
1883 | l2tp_session_set_header_len(session, tunnel->version); | |
1884 | ||
fd558d18 JC |
1885 | /* Bump the reference count. The session context is deleted |
1886 | * only when this drops to zero. | |
1887 | */ | |
1888 | l2tp_session_inc_refcount(session); | |
1889 | l2tp_tunnel_inc_refcount(tunnel); | |
1890 | ||
1891 | /* Ensure tunnel socket isn't deleted */ | |
1892 | sock_hold(tunnel->sock); | |
1893 | ||
1894 | /* Add session to the tunnel's hash list */ | |
1895 | write_lock_bh(&tunnel->hlist_lock); | |
1896 | hlist_add_head(&session->hlist, | |
1897 | l2tp_session_id_hash(tunnel, session_id)); | |
1898 | write_unlock_bh(&tunnel->hlist_lock); | |
1899 | ||
f7faffa3 JC |
1900 | /* And to the global session list if L2TPv3 */ |
1901 | if (tunnel->version != L2TP_HDR_VER_2) { | |
1902 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); | |
1903 | ||
e02d494d JC |
1904 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
1905 | hlist_add_head_rcu(&session->global_hlist, | |
1906 | l2tp_session_id_hash_2(pn, session_id)); | |
1907 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); | |
f7faffa3 JC |
1908 | } |
1909 | ||
fd558d18 JC |
1910 | /* Ignore management session in session count value */ |
1911 | if (session->session_id != 0) | |
1912 | atomic_inc(&l2tp_session_count); | |
1913 | } | |
1914 | ||
1915 | return session; | |
1916 | } | |
1917 | EXPORT_SYMBOL_GPL(l2tp_session_create); | |
1918 | ||
1919 | /***************************************************************************** | |
1920 | * Init and cleanup | |
1921 | *****************************************************************************/ | |
1922 | ||
1923 | static __net_init int l2tp_init_net(struct net *net) | |
1924 | { | |
e773aaff | 1925 | struct l2tp_net *pn = net_generic(net, l2tp_net_id); |
f7faffa3 | 1926 | int hash; |
fd558d18 | 1927 | |
fd558d18 | 1928 | INIT_LIST_HEAD(&pn->l2tp_tunnel_list); |
e02d494d | 1929 | spin_lock_init(&pn->l2tp_tunnel_list_lock); |
fd558d18 | 1930 | |
f7faffa3 JC |
1931 | for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) |
1932 | INIT_HLIST_HEAD(&pn->l2tp_session_hlist[hash]); | |
1933 | ||
e02d494d | 1934 | spin_lock_init(&pn->l2tp_session_hlist_lock); |
f7faffa3 | 1935 | |
fd558d18 | 1936 | return 0; |
fd558d18 JC |
1937 | } |
1938 | ||
167eb17e TP |
1939 | static __net_exit void l2tp_exit_net(struct net *net) |
1940 | { | |
1941 | struct l2tp_net *pn = l2tp_pernet(net); | |
1942 | struct l2tp_tunnel *tunnel = NULL; | |
1943 | ||
1944 | rcu_read_lock_bh(); | |
1945 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { | |
1946 | (void)l2tp_tunnel_delete(tunnel); | |
1947 | } | |
1948 | rcu_read_unlock_bh(); | |
1949 | } | |
1950 | ||
fd558d18 JC |
1951 | static struct pernet_operations l2tp_net_ops = { |
1952 | .init = l2tp_init_net, | |
167eb17e | 1953 | .exit = l2tp_exit_net, |
fd558d18 JC |
1954 | .id = &l2tp_net_id, |
1955 | .size = sizeof(struct l2tp_net), | |
1956 | }; | |
1957 | ||
1958 | static int __init l2tp_init(void) | |
1959 | { | |
1960 | int rc = 0; | |
1961 | ||
1962 | rc = register_pernet_device(&l2tp_net_ops); | |
1963 | if (rc) | |
1964 | goto out; | |
1965 | ||
f8ccac0e TP |
1966 | l2tp_wq = alloc_workqueue("l2tp", WQ_NON_REENTRANT | WQ_UNBOUND, 0); |
1967 | if (!l2tp_wq) { | |
1968 | pr_err("alloc_workqueue failed\n"); | |
1969 | rc = -ENOMEM; | |
1970 | goto out; | |
1971 | } | |
1972 | ||
a4ca44fa | 1973 | pr_info("L2TP core driver, %s\n", L2TP_DRV_VERSION); |
fd558d18 JC |
1974 | |
1975 | out: | |
1976 | return rc; | |
1977 | } | |
1978 | ||
1979 | static void __exit l2tp_exit(void) | |
1980 | { | |
1981 | unregister_pernet_device(&l2tp_net_ops); | |
f8ccac0e TP |
1982 | if (l2tp_wq) { |
1983 | destroy_workqueue(l2tp_wq); | |
1984 | l2tp_wq = NULL; | |
1985 | } | |
fd558d18 JC |
1986 | } |
1987 | ||
1988 | module_init(l2tp_init); | |
1989 | module_exit(l2tp_exit); | |
1990 | ||
1991 | MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); | |
1992 | MODULE_DESCRIPTION("L2TP core"); | |
1993 | MODULE_LICENSE("GPL"); | |
1994 | MODULE_VERSION(L2TP_DRV_VERSION); | |
1995 |