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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_tunnel_free(struct l2tp_tunnel *tunnel); |
fc130840 | 116 | |
8d8a51e2 DM |
117 | static inline struct l2tp_tunnel *l2tp_tunnel(struct sock *sk) |
118 | { | |
119 | return sk->sk_user_data; | |
120 | } | |
121 | ||
fd558d18 JC |
122 | static inline struct l2tp_net *l2tp_pernet(struct net *net) |
123 | { | |
124 | BUG_ON(!net); | |
125 | ||
126 | return net_generic(net, l2tp_net_id); | |
127 | } | |
128 | ||
fc130840 | 129 | /* Tunnel reference counts. Incremented per session that is added to |
130 | * the tunnel. | |
131 | */ | |
132 | static inline void l2tp_tunnel_inc_refcount_1(struct l2tp_tunnel *tunnel) | |
133 | { | |
134 | atomic_inc(&tunnel->ref_count); | |
135 | } | |
136 | ||
137 | static inline void l2tp_tunnel_dec_refcount_1(struct l2tp_tunnel *tunnel) | |
138 | { | |
139 | if (atomic_dec_and_test(&tunnel->ref_count)) | |
140 | l2tp_tunnel_free(tunnel); | |
141 | } | |
142 | #ifdef L2TP_REFCNT_DEBUG | |
a4ca44fa JP |
143 | #define l2tp_tunnel_inc_refcount(_t) \ |
144 | do { \ | |
145 | pr_debug("l2tp_tunnel_inc_refcount: %s:%d %s: cnt=%d\n", \ | |
146 | __func__, __LINE__, (_t)->name, \ | |
147 | atomic_read(&_t->ref_count)); \ | |
148 | l2tp_tunnel_inc_refcount_1(_t); \ | |
149 | } while (0) | |
150 | #define l2tp_tunnel_dec_refcount(_t) | |
151 | do { \ | |
152 | pr_debug("l2tp_tunnel_dec_refcount: %s:%d %s: cnt=%d\n", \ | |
153 | __func__, __LINE__, (_t)->name, \ | |
154 | atomic_read(&_t->ref_count)); \ | |
155 | l2tp_tunnel_dec_refcount_1(_t); \ | |
156 | } while (0) | |
fc130840 | 157 | #else |
158 | #define l2tp_tunnel_inc_refcount(t) l2tp_tunnel_inc_refcount_1(t) | |
159 | #define l2tp_tunnel_dec_refcount(t) l2tp_tunnel_dec_refcount_1(t) | |
160 | #endif | |
161 | ||
f7faffa3 JC |
162 | /* Session hash global list for L2TPv3. |
163 | * The session_id SHOULD be random according to RFC3931, but several | |
164 | * L2TP implementations use incrementing session_ids. So we do a real | |
165 | * hash on the session_id, rather than a simple bitmask. | |
166 | */ | |
167 | static inline struct hlist_head * | |
168 | l2tp_session_id_hash_2(struct l2tp_net *pn, u32 session_id) | |
169 | { | |
170 | return &pn->l2tp_session_hlist[hash_32(session_id, L2TP_HASH_BITS_2)]; | |
171 | ||
172 | } | |
173 | ||
80d84ef3 TP |
174 | /* Lookup the tunnel socket, possibly involving the fs code if the socket is |
175 | * owned by userspace. A struct sock returned from this function must be | |
176 | * released using l2tp_tunnel_sock_put once you're done with it. | |
177 | */ | |
b5d2b285 | 178 | static struct sock *l2tp_tunnel_sock_lookup(struct l2tp_tunnel *tunnel) |
80d84ef3 TP |
179 | { |
180 | int err = 0; | |
181 | struct socket *sock = NULL; | |
182 | struct sock *sk = NULL; | |
183 | ||
184 | if (!tunnel) | |
185 | goto out; | |
186 | ||
187 | if (tunnel->fd >= 0) { | |
188 | /* Socket is owned by userspace, who might be in the process | |
189 | * of closing it. Look the socket up using the fd to ensure | |
190 | * consistency. | |
191 | */ | |
192 | sock = sockfd_lookup(tunnel->fd, &err); | |
193 | if (sock) | |
194 | sk = sock->sk; | |
195 | } else { | |
196 | /* Socket is owned by kernelspace */ | |
197 | sk = tunnel->sock; | |
8abbbe8f | 198 | sock_hold(sk); |
80d84ef3 TP |
199 | } |
200 | ||
201 | out: | |
202 | return sk; | |
203 | } | |
80d84ef3 TP |
204 | |
205 | /* Drop a reference to a tunnel socket obtained via. l2tp_tunnel_sock_put */ | |
b5d2b285 | 206 | static void l2tp_tunnel_sock_put(struct sock *sk) |
80d84ef3 TP |
207 | { |
208 | struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); | |
209 | if (tunnel) { | |
210 | if (tunnel->fd >= 0) { | |
211 | /* Socket is owned by userspace */ | |
212 | sockfd_put(sk->sk_socket); | |
213 | } | |
214 | sock_put(sk); | |
215 | } | |
8abbbe8f | 216 | sock_put(sk); |
80d84ef3 | 217 | } |
80d84ef3 | 218 | |
f7faffa3 JC |
219 | /* Lookup a session by id in the global session list |
220 | */ | |
221 | static struct l2tp_session *l2tp_session_find_2(struct net *net, u32 session_id) | |
222 | { | |
223 | struct l2tp_net *pn = l2tp_pernet(net); | |
224 | struct hlist_head *session_list = | |
225 | l2tp_session_id_hash_2(pn, session_id); | |
226 | struct l2tp_session *session; | |
f7faffa3 | 227 | |
e02d494d | 228 | rcu_read_lock_bh(); |
b67bfe0d | 229 | hlist_for_each_entry_rcu(session, session_list, global_hlist) { |
f7faffa3 | 230 | if (session->session_id == session_id) { |
e02d494d | 231 | rcu_read_unlock_bh(); |
f7faffa3 JC |
232 | return session; |
233 | } | |
234 | } | |
e02d494d | 235 | rcu_read_unlock_bh(); |
f7faffa3 JC |
236 | |
237 | return NULL; | |
238 | } | |
239 | ||
fd558d18 JC |
240 | /* Session hash list. |
241 | * The session_id SHOULD be random according to RFC2661, but several | |
242 | * L2TP implementations (Cisco and Microsoft) use incrementing | |
243 | * session_ids. So we do a real hash on the session_id, rather than a | |
244 | * simple bitmask. | |
245 | */ | |
246 | static inline struct hlist_head * | |
247 | l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id) | |
248 | { | |
249 | return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)]; | |
250 | } | |
251 | ||
252 | /* Lookup a session by id | |
253 | */ | |
f7faffa3 | 254 | struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunnel, u32 session_id) |
fd558d18 | 255 | { |
f7faffa3 | 256 | struct hlist_head *session_list; |
fd558d18 | 257 | struct l2tp_session *session; |
fd558d18 | 258 | |
f7faffa3 JC |
259 | /* In L2TPv3, session_ids are unique over all tunnels and we |
260 | * sometimes need to look them up before we know the | |
261 | * tunnel. | |
262 | */ | |
263 | if (tunnel == NULL) | |
264 | return l2tp_session_find_2(net, session_id); | |
265 | ||
266 | session_list = l2tp_session_id_hash(tunnel, session_id); | |
fd558d18 | 267 | read_lock_bh(&tunnel->hlist_lock); |
b67bfe0d | 268 | hlist_for_each_entry(session, session_list, hlist) { |
fd558d18 JC |
269 | if (session->session_id == session_id) { |
270 | read_unlock_bh(&tunnel->hlist_lock); | |
271 | return session; | |
272 | } | |
273 | } | |
274 | read_unlock_bh(&tunnel->hlist_lock); | |
275 | ||
276 | return NULL; | |
277 | } | |
278 | EXPORT_SYMBOL_GPL(l2tp_session_find); | |
279 | ||
280 | struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth) | |
281 | { | |
282 | int hash; | |
fd558d18 JC |
283 | struct l2tp_session *session; |
284 | int count = 0; | |
285 | ||
286 | read_lock_bh(&tunnel->hlist_lock); | |
287 | for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { | |
b67bfe0d | 288 | hlist_for_each_entry(session, &tunnel->session_hlist[hash], hlist) { |
fd558d18 JC |
289 | if (++count > nth) { |
290 | read_unlock_bh(&tunnel->hlist_lock); | |
291 | return session; | |
292 | } | |
293 | } | |
294 | } | |
295 | ||
296 | read_unlock_bh(&tunnel->hlist_lock); | |
297 | ||
298 | return NULL; | |
299 | } | |
300 | EXPORT_SYMBOL_GPL(l2tp_session_find_nth); | |
301 | ||
309795f4 JC |
302 | /* Lookup a session by interface name. |
303 | * This is very inefficient but is only used by management interfaces. | |
304 | */ | |
305 | struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) | |
306 | { | |
307 | struct l2tp_net *pn = l2tp_pernet(net); | |
308 | int hash; | |
309795f4 JC |
309 | struct l2tp_session *session; |
310 | ||
e02d494d | 311 | rcu_read_lock_bh(); |
309795f4 | 312 | for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) { |
b67bfe0d | 313 | hlist_for_each_entry_rcu(session, &pn->l2tp_session_hlist[hash], global_hlist) { |
309795f4 | 314 | if (!strcmp(session->ifname, ifname)) { |
e02d494d | 315 | rcu_read_unlock_bh(); |
309795f4 JC |
316 | return session; |
317 | } | |
318 | } | |
319 | } | |
320 | ||
e02d494d | 321 | rcu_read_unlock_bh(); |
309795f4 JC |
322 | |
323 | return NULL; | |
324 | } | |
325 | EXPORT_SYMBOL_GPL(l2tp_session_find_by_ifname); | |
326 | ||
fd558d18 JC |
327 | /* Lookup a tunnel by id |
328 | */ | |
329 | struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id) | |
330 | { | |
331 | struct l2tp_tunnel *tunnel; | |
332 | struct l2tp_net *pn = l2tp_pernet(net); | |
333 | ||
e02d494d JC |
334 | rcu_read_lock_bh(); |
335 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { | |
fd558d18 | 336 | if (tunnel->tunnel_id == tunnel_id) { |
e02d494d | 337 | rcu_read_unlock_bh(); |
fd558d18 JC |
338 | return tunnel; |
339 | } | |
340 | } | |
e02d494d | 341 | rcu_read_unlock_bh(); |
fd558d18 JC |
342 | |
343 | return NULL; | |
344 | } | |
345 | EXPORT_SYMBOL_GPL(l2tp_tunnel_find); | |
346 | ||
347 | struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth) | |
348 | { | |
349 | struct l2tp_net *pn = l2tp_pernet(net); | |
350 | struct l2tp_tunnel *tunnel; | |
351 | int count = 0; | |
352 | ||
e02d494d JC |
353 | rcu_read_lock_bh(); |
354 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { | |
fd558d18 | 355 | if (++count > nth) { |
e02d494d | 356 | rcu_read_unlock_bh(); |
fd558d18 JC |
357 | return tunnel; |
358 | } | |
359 | } | |
360 | ||
e02d494d | 361 | rcu_read_unlock_bh(); |
fd558d18 JC |
362 | |
363 | return NULL; | |
364 | } | |
365 | EXPORT_SYMBOL_GPL(l2tp_tunnel_find_nth); | |
366 | ||
367 | /***************************************************************************** | |
368 | * Receive data handling | |
369 | *****************************************************************************/ | |
370 | ||
371 | /* Queue a skb in order. We come here only if the skb has an L2TP sequence | |
372 | * number. | |
373 | */ | |
374 | static void l2tp_recv_queue_skb(struct l2tp_session *session, struct sk_buff *skb) | |
375 | { | |
376 | struct sk_buff *skbp; | |
377 | struct sk_buff *tmp; | |
f7faffa3 | 378 | u32 ns = L2TP_SKB_CB(skb)->ns; |
fd558d18 JC |
379 | |
380 | spin_lock_bh(&session->reorder_q.lock); | |
381 | skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { | |
382 | if (L2TP_SKB_CB(skbp)->ns > ns) { | |
383 | __skb_queue_before(&session->reorder_q, skbp, skb); | |
a4ca44fa JP |
384 | l2tp_dbg(session, L2TP_MSG_SEQ, |
385 | "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n", | |
386 | session->name, ns, L2TP_SKB_CB(skbp)->ns, | |
387 | skb_queue_len(&session->reorder_q)); | |
7b7c0719 | 388 | atomic_long_inc(&session->stats.rx_oos_packets); |
fd558d18 JC |
389 | goto out; |
390 | } | |
391 | } | |
392 | ||
393 | __skb_queue_tail(&session->reorder_q, skb); | |
394 | ||
395 | out: | |
396 | spin_unlock_bh(&session->reorder_q.lock); | |
397 | } | |
398 | ||
399 | /* Dequeue a single skb. | |
400 | */ | |
401 | static void l2tp_recv_dequeue_skb(struct l2tp_session *session, struct sk_buff *skb) | |
402 | { | |
403 | struct l2tp_tunnel *tunnel = session->tunnel; | |
404 | int length = L2TP_SKB_CB(skb)->length; | |
405 | ||
406 | /* We're about to requeue the skb, so return resources | |
407 | * to its current owner (a socket receive buffer). | |
408 | */ | |
409 | skb_orphan(skb); | |
410 | ||
7b7c0719 TP |
411 | atomic_long_inc(&tunnel->stats.rx_packets); |
412 | atomic_long_add(length, &tunnel->stats.rx_bytes); | |
413 | atomic_long_inc(&session->stats.rx_packets); | |
414 | atomic_long_add(length, &session->stats.rx_bytes); | |
fd558d18 JC |
415 | |
416 | if (L2TP_SKB_CB(skb)->has_seq) { | |
417 | /* Bump our Nr */ | |
418 | session->nr++; | |
8a1631d5 | 419 | session->nr &= session->nr_max; |
f7faffa3 | 420 | |
a4ca44fa JP |
421 | l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated nr to %hu\n", |
422 | session->name, session->nr); | |
fd558d18 JC |
423 | } |
424 | ||
425 | /* call private receive handler */ | |
426 | if (session->recv_skb != NULL) | |
427 | (*session->recv_skb)(session, skb, L2TP_SKB_CB(skb)->length); | |
428 | else | |
429 | kfree_skb(skb); | |
430 | ||
431 | if (session->deref) | |
432 | (*session->deref)(session); | |
433 | } | |
434 | ||
435 | /* Dequeue skbs from the session's reorder_q, subject to packet order. | |
436 | * Skbs that have been in the queue for too long are simply discarded. | |
437 | */ | |
438 | static void l2tp_recv_dequeue(struct l2tp_session *session) | |
439 | { | |
440 | struct sk_buff *skb; | |
441 | struct sk_buff *tmp; | |
442 | ||
443 | /* If the pkt at the head of the queue has the nr that we | |
444 | * expect to send up next, dequeue it and any other | |
445 | * in-sequence packets behind it. | |
446 | */ | |
e2e210c0 | 447 | start: |
fd558d18 JC |
448 | spin_lock_bh(&session->reorder_q.lock); |
449 | skb_queue_walk_safe(&session->reorder_q, skb, tmp) { | |
450 | if (time_after(jiffies, L2TP_SKB_CB(skb)->expires)) { | |
7b7c0719 TP |
451 | atomic_long_inc(&session->stats.rx_seq_discards); |
452 | atomic_long_inc(&session->stats.rx_errors); | |
a4ca44fa JP |
453 | l2tp_dbg(session, L2TP_MSG_SEQ, |
454 | "%s: oos pkt %u len %d discarded (too old), waiting for %u, reorder_q_len=%d\n", | |
455 | session->name, L2TP_SKB_CB(skb)->ns, | |
456 | L2TP_SKB_CB(skb)->length, session->nr, | |
457 | skb_queue_len(&session->reorder_q)); | |
38d40b3f | 458 | session->reorder_skip = 1; |
fd558d18 JC |
459 | __skb_unlink(skb, &session->reorder_q); |
460 | kfree_skb(skb); | |
461 | if (session->deref) | |
462 | (*session->deref)(session); | |
463 | continue; | |
464 | } | |
465 | ||
466 | if (L2TP_SKB_CB(skb)->has_seq) { | |
38d40b3f | 467 | if (session->reorder_skip) { |
a4ca44fa JP |
468 | l2tp_dbg(session, L2TP_MSG_SEQ, |
469 | "%s: advancing nr to next pkt: %u -> %u", | |
470 | session->name, session->nr, | |
471 | L2TP_SKB_CB(skb)->ns); | |
38d40b3f JC |
472 | session->reorder_skip = 0; |
473 | session->nr = L2TP_SKB_CB(skb)->ns; | |
474 | } | |
fd558d18 | 475 | if (L2TP_SKB_CB(skb)->ns != session->nr) { |
a4ca44fa JP |
476 | l2tp_dbg(session, L2TP_MSG_SEQ, |
477 | "%s: holding oos pkt %u len %d, waiting for %u, reorder_q_len=%d\n", | |
478 | session->name, L2TP_SKB_CB(skb)->ns, | |
479 | L2TP_SKB_CB(skb)->length, session->nr, | |
480 | skb_queue_len(&session->reorder_q)); | |
fd558d18 JC |
481 | goto out; |
482 | } | |
483 | } | |
484 | __skb_unlink(skb, &session->reorder_q); | |
485 | ||
486 | /* Process the skb. We release the queue lock while we | |
487 | * do so to let other contexts process the queue. | |
488 | */ | |
489 | spin_unlock_bh(&session->reorder_q.lock); | |
490 | l2tp_recv_dequeue_skb(session, skb); | |
e2e210c0 | 491 | goto start; |
fd558d18 JC |
492 | } |
493 | ||
494 | out: | |
495 | spin_unlock_bh(&session->reorder_q.lock); | |
496 | } | |
497 | ||
8a1631d5 JC |
498 | static int l2tp_seq_check_rx_window(struct l2tp_session *session, u32 nr) |
499 | { | |
500 | u32 nws; | |
501 | ||
502 | if (nr >= session->nr) | |
503 | nws = nr - session->nr; | |
504 | else | |
505 | nws = (session->nr_max + 1) - (session->nr - nr); | |
506 | ||
507 | return nws < session->nr_window_size; | |
508 | } | |
509 | ||
b6dc01a4 JC |
510 | /* If packet has sequence numbers, queue it if acceptable. Returns 0 if |
511 | * acceptable, else non-zero. | |
512 | */ | |
513 | static int l2tp_recv_data_seq(struct l2tp_session *session, struct sk_buff *skb) | |
514 | { | |
8a1631d5 JC |
515 | if (!l2tp_seq_check_rx_window(session, L2TP_SKB_CB(skb)->ns)) { |
516 | /* Packet sequence number is outside allowed window. | |
517 | * Discard it. | |
518 | */ | |
519 | l2tp_dbg(session, L2TP_MSG_SEQ, | |
520 | "%s: pkt %u len %d discarded, outside window, nr=%u\n", | |
521 | session->name, L2TP_SKB_CB(skb)->ns, | |
522 | L2TP_SKB_CB(skb)->length, session->nr); | |
523 | goto discard; | |
524 | } | |
525 | ||
b6dc01a4 JC |
526 | if (session->reorder_timeout != 0) { |
527 | /* Packet reordering enabled. Add skb to session's | |
528 | * reorder queue, in order of ns. | |
529 | */ | |
530 | l2tp_recv_queue_skb(session, skb); | |
a0dbd822 JC |
531 | goto out; |
532 | } | |
533 | ||
534 | /* Packet reordering disabled. Discard out-of-sequence packets, while | |
535 | * tracking the number if in-sequence packets after the first OOS packet | |
536 | * is seen. After nr_oos_count_max in-sequence packets, reset the | |
537 | * sequence number to re-enable packet reception. | |
538 | */ | |
539 | if (L2TP_SKB_CB(skb)->ns == session->nr) { | |
540 | skb_queue_tail(&session->reorder_q, skb); | |
b6dc01a4 | 541 | } else { |
a0dbd822 JC |
542 | u32 nr_oos = L2TP_SKB_CB(skb)->ns; |
543 | u32 nr_next = (session->nr_oos + 1) & session->nr_max; | |
544 | ||
545 | if (nr_oos == nr_next) | |
546 | session->nr_oos_count++; | |
547 | else | |
548 | session->nr_oos_count = 0; | |
549 | ||
550 | session->nr_oos = nr_oos; | |
551 | if (session->nr_oos_count > session->nr_oos_count_max) { | |
552 | session->reorder_skip = 1; | |
553 | l2tp_dbg(session, L2TP_MSG_SEQ, | |
554 | "%s: %d oos packets received. Resetting sequence numbers\n", | |
555 | session->name, session->nr_oos_count); | |
556 | } | |
557 | if (!session->reorder_skip) { | |
b6dc01a4 JC |
558 | atomic_long_inc(&session->stats.rx_seq_discards); |
559 | l2tp_dbg(session, L2TP_MSG_SEQ, | |
560 | "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n", | |
561 | session->name, L2TP_SKB_CB(skb)->ns, | |
562 | L2TP_SKB_CB(skb)->length, session->nr, | |
563 | skb_queue_len(&session->reorder_q)); | |
564 | goto discard; | |
565 | } | |
566 | skb_queue_tail(&session->reorder_q, skb); | |
567 | } | |
568 | ||
a0dbd822 | 569 | out: |
b6dc01a4 JC |
570 | return 0; |
571 | ||
572 | discard: | |
573 | return 1; | |
574 | } | |
575 | ||
f7faffa3 JC |
576 | /* Do receive processing of L2TP data frames. We handle both L2TPv2 |
577 | * and L2TPv3 data frames here. | |
578 | * | |
579 | * L2TPv2 Data Message Header | |
580 | * | |
581 | * 0 1 2 3 | |
582 | * 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 | |
583 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
584 | * |T|L|x|x|S|x|O|P|x|x|x|x| Ver | Length (opt) | | |
585 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
586 | * | Tunnel ID | Session ID | | |
587 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
588 | * | Ns (opt) | Nr (opt) | | |
589 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
590 | * | Offset Size (opt) | Offset pad... (opt) | |
591 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
592 | * | |
593 | * Data frames are marked by T=0. All other fields are the same as | |
594 | * those in L2TP control frames. | |
595 | * | |
596 | * L2TPv3 Data Message Header | |
597 | * | |
598 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
599 | * | L2TP Session Header | | |
600 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
601 | * | L2-Specific Sublayer | | |
602 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
603 | * | Tunnel Payload ... | |
604 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
605 | * | |
606 | * L2TPv3 Session Header Over IP | |
607 | * | |
608 | * 0 1 2 3 | |
609 | * 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 | |
610 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
611 | * | Session ID | | |
612 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
613 | * | Cookie (optional, maximum 64 bits)... | |
614 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
615 | * | | |
616 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
617 | * | |
618 | * L2TPv3 L2-Specific Sublayer Format | |
619 | * | |
620 | * 0 1 2 3 | |
621 | * 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 | |
622 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
623 | * |x|S|x|x|x|x|x|x| Sequence Number | | |
624 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
625 | * | |
626 | * Cookie value, sublayer format and offset (pad) are negotiated with | |
627 | * the peer when the session is set up. Unlike L2TPv2, we do not need | |
628 | * to parse the packet header to determine if optional fields are | |
629 | * present. | |
630 | * | |
631 | * Caller must already have parsed the frame and determined that it is | |
632 | * a data (not control) frame before coming here. Fields up to the | |
633 | * session-id have already been parsed and ptr points to the data | |
634 | * after the session-id. | |
fd558d18 | 635 | */ |
f7faffa3 JC |
636 | void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, |
637 | unsigned char *ptr, unsigned char *optr, u16 hdrflags, | |
638 | int length, int (*payload_hook)(struct sk_buff *skb)) | |
fd558d18 | 639 | { |
f7faffa3 | 640 | struct l2tp_tunnel *tunnel = session->tunnel; |
fd558d18 | 641 | int offset; |
f7faffa3 | 642 | u32 ns, nr; |
fd558d18 JC |
643 | |
644 | /* The ref count is increased since we now hold a pointer to | |
645 | * the session. Take care to decrement the refcnt when exiting | |
646 | * this function from now on... | |
647 | */ | |
648 | l2tp_session_inc_refcount(session); | |
649 | if (session->ref) | |
650 | (*session->ref)(session); | |
651 | ||
f7faffa3 JC |
652 | /* Parse and check optional cookie */ |
653 | if (session->peer_cookie_len > 0) { | |
654 | if (memcmp(ptr, &session->peer_cookie[0], session->peer_cookie_len)) { | |
a4ca44fa JP |
655 | l2tp_info(tunnel, L2TP_MSG_DATA, |
656 | "%s: cookie mismatch (%u/%u). Discarding.\n", | |
657 | tunnel->name, tunnel->tunnel_id, | |
658 | session->session_id); | |
7b7c0719 | 659 | atomic_long_inc(&session->stats.rx_cookie_discards); |
f7faffa3 JC |
660 | goto discard; |
661 | } | |
662 | ptr += session->peer_cookie_len; | |
663 | } | |
664 | ||
fd558d18 JC |
665 | /* Handle the optional sequence numbers. Sequence numbers are |
666 | * in different places for L2TPv2 and L2TPv3. | |
667 | * | |
668 | * If we are the LAC, enable/disable sequence numbers under | |
669 | * the control of the LNS. If no sequence numbers present but | |
670 | * we were expecting them, discard frame. | |
671 | */ | |
672 | ns = nr = 0; | |
673 | L2TP_SKB_CB(skb)->has_seq = 0; | |
f7faffa3 JC |
674 | if (tunnel->version == L2TP_HDR_VER_2) { |
675 | if (hdrflags & L2TP_HDRFLAG_S) { | |
676 | ns = ntohs(*(__be16 *) ptr); | |
677 | ptr += 2; | |
678 | nr = ntohs(*(__be16 *) ptr); | |
679 | ptr += 2; | |
fd558d18 | 680 | |
f7faffa3 JC |
681 | /* Store L2TP info in the skb */ |
682 | L2TP_SKB_CB(skb)->ns = ns; | |
683 | L2TP_SKB_CB(skb)->has_seq = 1; | |
fd558d18 | 684 | |
a4ca44fa JP |
685 | l2tp_dbg(session, L2TP_MSG_SEQ, |
686 | "%s: recv data ns=%u, nr=%u, session nr=%u\n", | |
687 | session->name, ns, nr, session->nr); | |
f7faffa3 JC |
688 | } |
689 | } else if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { | |
690 | u32 l2h = ntohl(*(__be32 *) ptr); | |
691 | ||
692 | if (l2h & 0x40000000) { | |
693 | ns = l2h & 0x00ffffff; | |
694 | ||
695 | /* Store L2TP info in the skb */ | |
696 | L2TP_SKB_CB(skb)->ns = ns; | |
697 | L2TP_SKB_CB(skb)->has_seq = 1; | |
698 | ||
a4ca44fa JP |
699 | l2tp_dbg(session, L2TP_MSG_SEQ, |
700 | "%s: recv data ns=%u, session nr=%u\n", | |
701 | session->name, ns, session->nr); | |
f7faffa3 | 702 | } |
fd558d18 JC |
703 | } |
704 | ||
f7faffa3 JC |
705 | /* Advance past L2-specific header, if present */ |
706 | ptr += session->l2specific_len; | |
707 | ||
fd558d18 JC |
708 | if (L2TP_SKB_CB(skb)->has_seq) { |
709 | /* Received a packet with sequence numbers. If we're the LNS, | |
710 | * check if we sre sending sequence numbers and if not, | |
711 | * configure it so. | |
712 | */ | |
713 | if ((!session->lns_mode) && (!session->send_seq)) { | |
a4ca44fa JP |
714 | l2tp_info(session, L2TP_MSG_SEQ, |
715 | "%s: requested to enable seq numbers by LNS\n", | |
716 | session->name); | |
fd558d18 | 717 | session->send_seq = -1; |
f7faffa3 | 718 | l2tp_session_set_header_len(session, tunnel->version); |
fd558d18 JC |
719 | } |
720 | } else { | |
721 | /* No sequence numbers. | |
722 | * If user has configured mandatory sequence numbers, discard. | |
723 | */ | |
724 | if (session->recv_seq) { | |
a4ca44fa JP |
725 | l2tp_warn(session, L2TP_MSG_SEQ, |
726 | "%s: recv data has no seq numbers when required. Discarding.\n", | |
727 | session->name); | |
7b7c0719 | 728 | atomic_long_inc(&session->stats.rx_seq_discards); |
fd558d18 JC |
729 | goto discard; |
730 | } | |
731 | ||
732 | /* If we're the LAC and we're sending sequence numbers, the | |
733 | * LNS has requested that we no longer send sequence numbers. | |
734 | * If we're the LNS and we're sending sequence numbers, the | |
735 | * LAC is broken. Discard the frame. | |
736 | */ | |
737 | if ((!session->lns_mode) && (session->send_seq)) { | |
a4ca44fa JP |
738 | l2tp_info(session, L2TP_MSG_SEQ, |
739 | "%s: requested to disable seq numbers by LNS\n", | |
740 | session->name); | |
fd558d18 | 741 | session->send_seq = 0; |
f7faffa3 | 742 | l2tp_session_set_header_len(session, tunnel->version); |
fd558d18 | 743 | } else if (session->send_seq) { |
a4ca44fa JP |
744 | l2tp_warn(session, L2TP_MSG_SEQ, |
745 | "%s: recv data has no seq numbers when required. Discarding.\n", | |
746 | session->name); | |
7b7c0719 | 747 | atomic_long_inc(&session->stats.rx_seq_discards); |
fd558d18 JC |
748 | goto discard; |
749 | } | |
750 | } | |
751 | ||
f7faffa3 JC |
752 | /* Session data offset is handled differently for L2TPv2 and |
753 | * L2TPv3. For L2TPv2, there is an optional 16-bit value in | |
754 | * the header. For L2TPv3, the offset is negotiated using AVPs | |
755 | * in the session setup control protocol. | |
756 | */ | |
757 | if (tunnel->version == L2TP_HDR_VER_2) { | |
758 | /* If offset bit set, skip it. */ | |
759 | if (hdrflags & L2TP_HDRFLAG_O) { | |
760 | offset = ntohs(*(__be16 *)ptr); | |
761 | ptr += 2 + offset; | |
762 | } | |
763 | } else | |
764 | ptr += session->offset; | |
fd558d18 JC |
765 | |
766 | offset = ptr - optr; | |
767 | if (!pskb_may_pull(skb, offset)) | |
768 | goto discard; | |
769 | ||
770 | __skb_pull(skb, offset); | |
771 | ||
772 | /* If caller wants to process the payload before we queue the | |
773 | * packet, do so now. | |
774 | */ | |
775 | if (payload_hook) | |
776 | if ((*payload_hook)(skb)) | |
777 | goto discard; | |
778 | ||
779 | /* Prepare skb for adding to the session's reorder_q. Hold | |
780 | * packets for max reorder_timeout or 1 second if not | |
781 | * reordering. | |
782 | */ | |
783 | L2TP_SKB_CB(skb)->length = length; | |
784 | L2TP_SKB_CB(skb)->expires = jiffies + | |
785 | (session->reorder_timeout ? session->reorder_timeout : HZ); | |
786 | ||
787 | /* Add packet to the session's receive queue. Reordering is done here, if | |
788 | * enabled. Saved L2TP protocol info is stored in skb->sb[]. | |
789 | */ | |
790 | if (L2TP_SKB_CB(skb)->has_seq) { | |
b6dc01a4 JC |
791 | if (l2tp_recv_data_seq(session, skb)) |
792 | goto discard; | |
fd558d18 JC |
793 | } else { |
794 | /* No sequence numbers. Add the skb to the tail of the | |
795 | * reorder queue. This ensures that it will be | |
796 | * delivered after all previous sequenced skbs. | |
797 | */ | |
798 | skb_queue_tail(&session->reorder_q, skb); | |
799 | } | |
800 | ||
801 | /* Try to dequeue as many skbs from reorder_q as we can. */ | |
802 | l2tp_recv_dequeue(session); | |
803 | ||
804 | l2tp_session_dec_refcount(session); | |
805 | ||
f7faffa3 | 806 | return; |
fd558d18 JC |
807 | |
808 | discard: | |
7b7c0719 | 809 | atomic_long_inc(&session->stats.rx_errors); |
fd558d18 JC |
810 | kfree_skb(skb); |
811 | ||
812 | if (session->deref) | |
813 | (*session->deref)(session); | |
814 | ||
815 | l2tp_session_dec_refcount(session); | |
f7faffa3 JC |
816 | } |
817 | EXPORT_SYMBOL(l2tp_recv_common); | |
818 | ||
48f72f92 TP |
819 | /* Drop skbs from the session's reorder_q |
820 | */ | |
821 | int l2tp_session_queue_purge(struct l2tp_session *session) | |
822 | { | |
823 | struct sk_buff *skb = NULL; | |
824 | BUG_ON(!session); | |
825 | BUG_ON(session->magic != L2TP_SESSION_MAGIC); | |
826 | while ((skb = skb_dequeue(&session->reorder_q))) { | |
827 | atomic_long_inc(&session->stats.rx_errors); | |
828 | kfree_skb(skb); | |
829 | if (session->deref) | |
830 | (*session->deref)(session); | |
831 | } | |
832 | return 0; | |
833 | } | |
834 | EXPORT_SYMBOL_GPL(l2tp_session_queue_purge); | |
835 | ||
f7faffa3 JC |
836 | /* Internal UDP receive frame. Do the real work of receiving an L2TP data frame |
837 | * here. The skb is not on a list when we get here. | |
838 | * Returns 0 if the packet was a data packet and was successfully passed on. | |
839 | * Returns 1 if the packet was not a good data packet and could not be | |
840 | * forwarded. All such packets are passed up to userspace to deal with. | |
841 | */ | |
fc130840 | 842 | static int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, |
843 | int (*payload_hook)(struct sk_buff *skb)) | |
f7faffa3 JC |
844 | { |
845 | struct l2tp_session *session = NULL; | |
846 | unsigned char *ptr, *optr; | |
847 | u16 hdrflags; | |
848 | u32 tunnel_id, session_id; | |
f7faffa3 JC |
849 | u16 version; |
850 | int length; | |
851 | ||
58d6085c | 852 | /* UDP has verifed checksum */ |
f7faffa3 JC |
853 | |
854 | /* UDP always verifies the packet length. */ | |
855 | __skb_pull(skb, sizeof(struct udphdr)); | |
856 | ||
857 | /* Short packet? */ | |
858 | if (!pskb_may_pull(skb, L2TP_HDR_SIZE_SEQ)) { | |
a4ca44fa JP |
859 | l2tp_info(tunnel, L2TP_MSG_DATA, |
860 | "%s: recv short packet (len=%d)\n", | |
861 | tunnel->name, skb->len); | |
f7faffa3 JC |
862 | goto error; |
863 | } | |
864 | ||
f7faffa3 JC |
865 | /* Trace packet contents, if enabled */ |
866 | if (tunnel->debug & L2TP_MSG_DATA) { | |
867 | length = min(32u, skb->len); | |
868 | if (!pskb_may_pull(skb, length)) | |
869 | goto error; | |
870 | ||
a4ca44fa JP |
871 | pr_debug("%s: recv\n", tunnel->name); |
872 | print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, skb->data, length); | |
f7faffa3 JC |
873 | } |
874 | ||
e50e705c ED |
875 | /* Point to L2TP header */ |
876 | optr = ptr = skb->data; | |
877 | ||
f7faffa3 JC |
878 | /* Get L2TP header flags */ |
879 | hdrflags = ntohs(*(__be16 *) ptr); | |
880 | ||
881 | /* Check protocol version */ | |
882 | version = hdrflags & L2TP_HDR_VER_MASK; | |
883 | if (version != tunnel->version) { | |
a4ca44fa JP |
884 | l2tp_info(tunnel, L2TP_MSG_DATA, |
885 | "%s: recv protocol version mismatch: got %d expected %d\n", | |
886 | tunnel->name, version, tunnel->version); | |
f7faffa3 JC |
887 | goto error; |
888 | } | |
889 | ||
890 | /* Get length of L2TP packet */ | |
891 | length = skb->len; | |
892 | ||
893 | /* If type is control packet, it is handled by userspace. */ | |
894 | if (hdrflags & L2TP_HDRFLAG_T) { | |
a4ca44fa JP |
895 | l2tp_dbg(tunnel, L2TP_MSG_DATA, |
896 | "%s: recv control packet, len=%d\n", | |
897 | tunnel->name, length); | |
f7faffa3 JC |
898 | goto error; |
899 | } | |
900 | ||
901 | /* Skip flags */ | |
902 | ptr += 2; | |
903 | ||
904 | if (tunnel->version == L2TP_HDR_VER_2) { | |
905 | /* If length is present, skip it */ | |
906 | if (hdrflags & L2TP_HDRFLAG_L) | |
907 | ptr += 2; | |
908 | ||
909 | /* Extract tunnel and session ID */ | |
910 | tunnel_id = ntohs(*(__be16 *) ptr); | |
911 | ptr += 2; | |
912 | session_id = ntohs(*(__be16 *) ptr); | |
913 | ptr += 2; | |
914 | } else { | |
915 | ptr += 2; /* skip reserved bits */ | |
916 | tunnel_id = tunnel->tunnel_id; | |
917 | session_id = ntohl(*(__be32 *) ptr); | |
918 | ptr += 4; | |
919 | } | |
920 | ||
921 | /* Find the session context */ | |
922 | session = l2tp_session_find(tunnel->l2tp_net, tunnel, session_id); | |
309795f4 | 923 | if (!session || !session->recv_skb) { |
f7faffa3 | 924 | /* Not found? Pass to userspace to deal with */ |
a4ca44fa JP |
925 | l2tp_info(tunnel, L2TP_MSG_DATA, |
926 | "%s: no session found (%u/%u). Passing up.\n", | |
927 | tunnel->name, tunnel_id, session_id); | |
f7faffa3 JC |
928 | goto error; |
929 | } | |
930 | ||
931 | l2tp_recv_common(session, skb, ptr, optr, hdrflags, length, payload_hook); | |
fd558d18 JC |
932 | |
933 | return 0; | |
934 | ||
fd558d18 JC |
935 | error: |
936 | /* Put UDP header back */ | |
937 | __skb_push(skb, sizeof(struct udphdr)); | |
938 | ||
939 | return 1; | |
940 | } | |
fd558d18 JC |
941 | |
942 | /* UDP encapsulation receive handler. See net/ipv4/udp.c. | |
943 | * Return codes: | |
944 | * 0 : success. | |
945 | * <0: error | |
946 | * >0: skb should be passed up to userspace as UDP. | |
947 | */ | |
948 | int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) | |
949 | { | |
950 | struct l2tp_tunnel *tunnel; | |
951 | ||
952 | tunnel = l2tp_sock_to_tunnel(sk); | |
953 | if (tunnel == NULL) | |
954 | goto pass_up; | |
955 | ||
a4ca44fa JP |
956 | l2tp_dbg(tunnel, L2TP_MSG_DATA, "%s: received %d bytes\n", |
957 | tunnel->name, skb->len); | |
fd558d18 JC |
958 | |
959 | if (l2tp_udp_recv_core(tunnel, skb, tunnel->recv_payload_hook)) | |
960 | goto pass_up_put; | |
961 | ||
962 | sock_put(sk); | |
963 | return 0; | |
964 | ||
965 | pass_up_put: | |
966 | sock_put(sk); | |
967 | pass_up: | |
968 | return 1; | |
969 | } | |
970 | EXPORT_SYMBOL_GPL(l2tp_udp_encap_recv); | |
971 | ||
972 | /************************************************************************ | |
973 | * Transmit handling | |
974 | ***********************************************************************/ | |
975 | ||
976 | /* Build an L2TP header for the session into the buffer provided. | |
977 | */ | |
f7faffa3 | 978 | static int l2tp_build_l2tpv2_header(struct l2tp_session *session, void *buf) |
fd558d18 | 979 | { |
f7faffa3 | 980 | struct l2tp_tunnel *tunnel = session->tunnel; |
fd558d18 | 981 | __be16 *bufp = buf; |
f7faffa3 | 982 | __be16 *optr = buf; |
fd558d18 JC |
983 | u16 flags = L2TP_HDR_VER_2; |
984 | u32 tunnel_id = tunnel->peer_tunnel_id; | |
985 | u32 session_id = session->peer_session_id; | |
986 | ||
987 | if (session->send_seq) | |
988 | flags |= L2TP_HDRFLAG_S; | |
989 | ||
990 | /* Setup L2TP header. */ | |
991 | *bufp++ = htons(flags); | |
992 | *bufp++ = htons(tunnel_id); | |
993 | *bufp++ = htons(session_id); | |
994 | if (session->send_seq) { | |
995 | *bufp++ = htons(session->ns); | |
996 | *bufp++ = 0; | |
997 | session->ns++; | |
f7faffa3 | 998 | session->ns &= 0xffff; |
a4ca44fa JP |
999 | l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated ns to %u\n", |
1000 | session->name, session->ns); | |
fd558d18 | 1001 | } |
f7faffa3 JC |
1002 | |
1003 | return bufp - optr; | |
fd558d18 JC |
1004 | } |
1005 | ||
f7faffa3 | 1006 | static int l2tp_build_l2tpv3_header(struct l2tp_session *session, void *buf) |
fd558d18 | 1007 | { |
0d76751f | 1008 | struct l2tp_tunnel *tunnel = session->tunnel; |
f7faffa3 JC |
1009 | char *bufp = buf; |
1010 | char *optr = bufp; | |
f7faffa3 | 1011 | |
0d76751f JC |
1012 | /* Setup L2TP header. The header differs slightly for UDP and |
1013 | * IP encapsulations. For UDP, there is 4 bytes of flags. | |
1014 | */ | |
1015 | if (tunnel->encap == L2TP_ENCAPTYPE_UDP) { | |
1016 | u16 flags = L2TP_HDR_VER_3; | |
1017 | *((__be16 *) bufp) = htons(flags); | |
1018 | bufp += 2; | |
1019 | *((__be16 *) bufp) = 0; | |
1020 | bufp += 2; | |
1021 | } | |
1022 | ||
f7faffa3 JC |
1023 | *((__be32 *) bufp) = htonl(session->peer_session_id); |
1024 | bufp += 4; | |
1025 | if (session->cookie_len) { | |
1026 | memcpy(bufp, &session->cookie[0], session->cookie_len); | |
1027 | bufp += session->cookie_len; | |
1028 | } | |
1029 | if (session->l2specific_len) { | |
1030 | if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { | |
1031 | u32 l2h = 0; | |
1032 | if (session->send_seq) { | |
1033 | l2h = 0x40000000 | session->ns; | |
1034 | session->ns++; | |
1035 | session->ns &= 0xffffff; | |
a4ca44fa JP |
1036 | l2tp_dbg(session, L2TP_MSG_SEQ, |
1037 | "%s: updated ns to %u\n", | |
1038 | session->name, session->ns); | |
f7faffa3 JC |
1039 | } |
1040 | ||
1041 | *((__be32 *) bufp) = htonl(l2h); | |
1042 | } | |
1043 | bufp += session->l2specific_len; | |
1044 | } | |
1045 | if (session->offset) | |
1046 | bufp += session->offset; | |
fd558d18 | 1047 | |
f7faffa3 | 1048 | return bufp - optr; |
fd558d18 | 1049 | } |
fd558d18 | 1050 | |
fc130840 | 1051 | static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb, |
d9d8da80 | 1052 | struct flowi *fl, size_t data_len) |
fd558d18 JC |
1053 | { |
1054 | struct l2tp_tunnel *tunnel = session->tunnel; | |
1055 | unsigned int len = skb->len; | |
1056 | int error; | |
1057 | ||
1058 | /* Debug */ | |
1059 | if (session->send_seq) | |
a4ca44fa JP |
1060 | l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %Zd bytes, ns=%u\n", |
1061 | session->name, data_len, session->ns - 1); | |
fd558d18 | 1062 | else |
a4ca44fa JP |
1063 | l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %Zd bytes\n", |
1064 | session->name, data_len); | |
fd558d18 JC |
1065 | |
1066 | if (session->debug & L2TP_MSG_DATA) { | |
0d76751f JC |
1067 | int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
1068 | unsigned char *datap = skb->data + uhlen; | |
fd558d18 | 1069 | |
a4ca44fa JP |
1070 | pr_debug("%s: xmit\n", session->name); |
1071 | print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, | |
1072 | datap, min_t(size_t, 32, len - uhlen)); | |
fd558d18 JC |
1073 | } |
1074 | ||
1075 | /* Queue the packet to IP for output */ | |
4e15ed4d | 1076 | skb->local_df = 1; |
d2cf3361 | 1077 | #if IS_ENABLED(CONFIG_IPV6) |
746e3499 | 1078 | if (tunnel->sock->sk_family == PF_INET6 && !tunnel->v4mapped) |
b0270e91 | 1079 | error = inet6_csk_xmit(tunnel->sock, skb, NULL); |
d2cf3361 BL |
1080 | else |
1081 | #endif | |
b0270e91 | 1082 | error = ip_queue_xmit(tunnel->sock, skb, fl); |
fd558d18 JC |
1083 | |
1084 | /* Update stats */ | |
1085 | if (error >= 0) { | |
7b7c0719 TP |
1086 | atomic_long_inc(&tunnel->stats.tx_packets); |
1087 | atomic_long_add(len, &tunnel->stats.tx_bytes); | |
1088 | atomic_long_inc(&session->stats.tx_packets); | |
1089 | atomic_long_add(len, &session->stats.tx_bytes); | |
fd558d18 | 1090 | } else { |
7b7c0719 TP |
1091 | atomic_long_inc(&tunnel->stats.tx_errors); |
1092 | atomic_long_inc(&session->stats.tx_errors); | |
fd558d18 JC |
1093 | } |
1094 | ||
1095 | return 0; | |
1096 | } | |
fd558d18 | 1097 | |
d2cf3361 BL |
1098 | #if IS_ENABLED(CONFIG_IPV6) |
1099 | static void l2tp_xmit_ipv6_csum(struct sock *sk, struct sk_buff *skb, | |
1100 | int udp_len) | |
1101 | { | |
1102 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1103 | struct udphdr *uh = udp_hdr(skb); | |
1104 | ||
1105 | if (!skb_dst(skb) || !skb_dst(skb)->dev || | |
1106 | !(skb_dst(skb)->dev->features & NETIF_F_IPV6_CSUM)) { | |
1107 | __wsum csum = skb_checksum(skb, 0, udp_len, 0); | |
1108 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
efe4208f | 1109 | uh->check = csum_ipv6_magic(&np->saddr, &sk->sk_v6_daddr, udp_len, |
d2cf3361 BL |
1110 | IPPROTO_UDP, csum); |
1111 | if (uh->check == 0) | |
1112 | uh->check = CSUM_MANGLED_0; | |
1113 | } else { | |
1114 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1115 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
1116 | skb->csum_offset = offsetof(struct udphdr, check); | |
efe4208f | 1117 | uh->check = ~csum_ipv6_magic(&np->saddr, &sk->sk_v6_daddr, |
d2cf3361 BL |
1118 | udp_len, IPPROTO_UDP, 0); |
1119 | } | |
1120 | } | |
1121 | #endif | |
1122 | ||
fd558d18 JC |
1123 | /* If caller requires the skb to have a ppp header, the header must be |
1124 | * inserted in the skb data before calling this function. | |
1125 | */ | |
1126 | int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len) | |
1127 | { | |
1128 | int data_len = skb->len; | |
0d76751f JC |
1129 | struct l2tp_tunnel *tunnel = session->tunnel; |
1130 | struct sock *sk = tunnel->sock; | |
d9d8da80 | 1131 | struct flowi *fl; |
fd558d18 | 1132 | struct udphdr *uh; |
fd558d18 JC |
1133 | struct inet_sock *inet; |
1134 | __wsum csum; | |
fd558d18 | 1135 | int headroom; |
0d76751f JC |
1136 | int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
1137 | int udp_len; | |
b8c84307 | 1138 | int ret = NET_XMIT_SUCCESS; |
fd558d18 JC |
1139 | |
1140 | /* Check that there's enough headroom in the skb to insert IP, | |
1141 | * UDP and L2TP headers. If not enough, expand it to | |
1142 | * make room. Adjust truesize. | |
1143 | */ | |
1144 | headroom = NET_SKB_PAD + sizeof(struct iphdr) + | |
0d76751f | 1145 | uhlen + hdr_len; |
835acf5d | 1146 | if (skb_cow_head(skb, headroom)) { |
b8c84307 ED |
1147 | kfree_skb(skb); |
1148 | return NET_XMIT_DROP; | |
835acf5d | 1149 | } |
fd558d18 | 1150 | |
fd558d18 | 1151 | /* Setup L2TP header */ |
f7faffa3 | 1152 | session->build_header(session, __skb_push(skb, hdr_len)); |
fd558d18 | 1153 | |
0d76751f | 1154 | /* Reset skb netfilter state */ |
fd558d18 JC |
1155 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
1156 | IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | | |
1157 | IPSKB_REROUTED); | |
1158 | nf_reset(skb); | |
1159 | ||
6af88da1 DM |
1160 | bh_lock_sock(sk); |
1161 | if (sock_owned_by_user(sk)) { | |
b8c84307 ED |
1162 | kfree_skb(skb); |
1163 | ret = NET_XMIT_DROP; | |
6af88da1 DM |
1164 | goto out_unlock; |
1165 | } | |
1166 | ||
fd558d18 JC |
1167 | /* Get routing info from the tunnel socket */ |
1168 | skb_dst_drop(skb); | |
71b1391a | 1169 | skb_dst_set(skb, dst_clone(__sk_dst_check(sk, 0))); |
fd558d18 | 1170 | |
d9d8da80 DM |
1171 | inet = inet_sk(sk); |
1172 | fl = &inet->cork.fl; | |
0d76751f JC |
1173 | switch (tunnel->encap) { |
1174 | case L2TP_ENCAPTYPE_UDP: | |
1175 | /* Setup UDP header */ | |
0d76751f JC |
1176 | __skb_push(skb, sizeof(*uh)); |
1177 | skb_reset_transport_header(skb); | |
1178 | uh = udp_hdr(skb); | |
1179 | uh->source = inet->inet_sport; | |
1180 | uh->dest = inet->inet_dport; | |
1181 | udp_len = uhlen + hdr_len + data_len; | |
1182 | uh->len = htons(udp_len); | |
1183 | uh->check = 0; | |
1184 | ||
1185 | /* Calculate UDP checksum if configured to do so */ | |
d2cf3361 | 1186 | #if IS_ENABLED(CONFIG_IPV6) |
e18503f4 | 1187 | if (sk->sk_family == PF_INET6 && !tunnel->v4mapped) |
d2cf3361 BL |
1188 | l2tp_xmit_ipv6_csum(sk, skb, udp_len); |
1189 | else | |
1190 | #endif | |
0d76751f JC |
1191 | if (sk->sk_no_check == UDP_CSUM_NOXMIT) |
1192 | skb->ip_summed = CHECKSUM_NONE; | |
1193 | else if ((skb_dst(skb) && skb_dst(skb)->dev) && | |
1194 | (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) { | |
1195 | skb->ip_summed = CHECKSUM_COMPLETE; | |
1196 | csum = skb_checksum(skb, 0, udp_len, 0); | |
1197 | uh->check = csum_tcpudp_magic(inet->inet_saddr, | |
1198 | inet->inet_daddr, | |
1199 | udp_len, IPPROTO_UDP, csum); | |
1200 | if (uh->check == 0) | |
1201 | uh->check = CSUM_MANGLED_0; | |
1202 | } else { | |
1203 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1204 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
1205 | skb->csum_offset = offsetof(struct udphdr, check); | |
1206 | uh->check = ~csum_tcpudp_magic(inet->inet_saddr, | |
1207 | inet->inet_daddr, | |
1208 | udp_len, IPPROTO_UDP, 0); | |
1209 | } | |
1210 | break; | |
1211 | ||
1212 | case L2TP_ENCAPTYPE_IP: | |
1213 | break; | |
fd558d18 JC |
1214 | } |
1215 | ||
d9d8da80 | 1216 | l2tp_xmit_core(session, skb, fl, data_len); |
6af88da1 DM |
1217 | out_unlock: |
1218 | bh_unlock_sock(sk); | |
fd558d18 | 1219 | |
b8c84307 | 1220 | return ret; |
fd558d18 JC |
1221 | } |
1222 | EXPORT_SYMBOL_GPL(l2tp_xmit_skb); | |
1223 | ||
1224 | /***************************************************************************** | |
1225 | * Tinnel and session create/destroy. | |
1226 | *****************************************************************************/ | |
1227 | ||
1228 | /* Tunnel socket destruct hook. | |
1229 | * The tunnel context is deleted only when all session sockets have been | |
1230 | * closed. | |
1231 | */ | |
fc130840 | 1232 | static void l2tp_tunnel_destruct(struct sock *sk) |
fd558d18 | 1233 | { |
8d8a51e2 | 1234 | struct l2tp_tunnel *tunnel = l2tp_tunnel(sk); |
f8ccac0e | 1235 | struct l2tp_net *pn; |
fd558d18 | 1236 | |
fd558d18 JC |
1237 | if (tunnel == NULL) |
1238 | goto end; | |
1239 | ||
a4ca44fa | 1240 | l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing...\n", tunnel->name); |
fd558d18 | 1241 | |
fd558d18 | 1242 | |
f8ccac0e | 1243 | /* Disable udp encapsulation */ |
0d76751f JC |
1244 | switch (tunnel->encap) { |
1245 | case L2TP_ENCAPTYPE_UDP: | |
1246 | /* No longer an encapsulation socket. See net/ipv4/udp.c */ | |
1247 | (udp_sk(sk))->encap_type = 0; | |
1248 | (udp_sk(sk))->encap_rcv = NULL; | |
9980d001 | 1249 | (udp_sk(sk))->encap_destroy = NULL; |
0d76751f JC |
1250 | break; |
1251 | case L2TP_ENCAPTYPE_IP: | |
1252 | break; | |
1253 | } | |
fd558d18 JC |
1254 | |
1255 | /* Remove hooks into tunnel socket */ | |
fd558d18 JC |
1256 | sk->sk_destruct = tunnel->old_sk_destruct; |
1257 | sk->sk_user_data = NULL; | |
f8ccac0e | 1258 | tunnel->sock = NULL; |
fd558d18 | 1259 | |
f8ccac0e TP |
1260 | /* Remove the tunnel struct from the tunnel list */ |
1261 | pn = l2tp_pernet(tunnel->l2tp_net); | |
1262 | spin_lock_bh(&pn->l2tp_tunnel_list_lock); | |
1263 | list_del_rcu(&tunnel->list); | |
1264 | spin_unlock_bh(&pn->l2tp_tunnel_list_lock); | |
1265 | atomic_dec(&l2tp_tunnel_count); | |
fd558d18 | 1266 | |
f8ccac0e | 1267 | l2tp_tunnel_closeall(tunnel); |
fd558d18 JC |
1268 | l2tp_tunnel_dec_refcount(tunnel); |
1269 | ||
f8ccac0e TP |
1270 | /* Call the original destructor */ |
1271 | if (sk->sk_destruct) | |
1272 | (*sk->sk_destruct)(sk); | |
fd558d18 JC |
1273 | end: |
1274 | return; | |
1275 | } | |
fd558d18 JC |
1276 | |
1277 | /* When the tunnel is closed, all the attached sessions need to go too. | |
1278 | */ | |
e34f4c70 | 1279 | void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel) |
fd558d18 JC |
1280 | { |
1281 | int hash; | |
1282 | struct hlist_node *walk; | |
1283 | struct hlist_node *tmp; | |
1284 | struct l2tp_session *session; | |
1285 | ||
1286 | BUG_ON(tunnel == NULL); | |
1287 | ||
a4ca44fa JP |
1288 | l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing all sessions...\n", |
1289 | tunnel->name); | |
fd558d18 JC |
1290 | |
1291 | write_lock_bh(&tunnel->hlist_lock); | |
1292 | for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { | |
1293 | again: | |
1294 | hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { | |
1295 | session = hlist_entry(walk, struct l2tp_session, hlist); | |
1296 | ||
a4ca44fa JP |
1297 | l2tp_info(session, L2TP_MSG_CONTROL, |
1298 | "%s: closing session\n", session->name); | |
fd558d18 JC |
1299 | |
1300 | hlist_del_init(&session->hlist); | |
1301 | ||
fd558d18 JC |
1302 | if (session->ref != NULL) |
1303 | (*session->ref)(session); | |
1304 | ||
1305 | write_unlock_bh(&tunnel->hlist_lock); | |
1306 | ||
f6e16b29 | 1307 | __l2tp_session_unhash(session); |
4c6e2fd3 TP |
1308 | l2tp_session_queue_purge(session); |
1309 | ||
fd558d18 JC |
1310 | if (session->session_close != NULL) |
1311 | (*session->session_close)(session); | |
1312 | ||
1313 | if (session->deref != NULL) | |
1314 | (*session->deref)(session); | |
1315 | ||
9980d001 TP |
1316 | l2tp_session_dec_refcount(session); |
1317 | ||
fd558d18 JC |
1318 | write_lock_bh(&tunnel->hlist_lock); |
1319 | ||
1320 | /* Now restart from the beginning of this hash | |
1321 | * chain. We always remove a session from the | |
1322 | * list so we are guaranteed to make forward | |
1323 | * progress. | |
1324 | */ | |
1325 | goto again; | |
1326 | } | |
1327 | } | |
1328 | write_unlock_bh(&tunnel->hlist_lock); | |
1329 | } | |
e34f4c70 | 1330 | EXPORT_SYMBOL_GPL(l2tp_tunnel_closeall); |
fd558d18 | 1331 | |
9980d001 TP |
1332 | /* Tunnel socket destroy hook for UDP encapsulation */ |
1333 | static void l2tp_udp_encap_destroy(struct sock *sk) | |
1334 | { | |
1335 | struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); | |
1336 | if (tunnel) { | |
1337 | l2tp_tunnel_closeall(tunnel); | |
1338 | sock_put(sk); | |
1339 | } | |
1340 | } | |
1341 | ||
fd558d18 JC |
1342 | /* Really kill the tunnel. |
1343 | * Come here only when all sessions have been cleared from the tunnel. | |
1344 | */ | |
fc130840 | 1345 | static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel) |
fd558d18 | 1346 | { |
fd558d18 JC |
1347 | BUG_ON(atomic_read(&tunnel->ref_count) != 0); |
1348 | BUG_ON(tunnel->sock != NULL); | |
a4ca44fa | 1349 | l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: free...\n", tunnel->name); |
99469c32 | 1350 | kfree_rcu(tunnel, rcu); |
f8ccac0e | 1351 | } |
fd558d18 | 1352 | |
f8ccac0e TP |
1353 | /* Workqueue tunnel deletion function */ |
1354 | static void l2tp_tunnel_del_work(struct work_struct *work) | |
1355 | { | |
1356 | struct l2tp_tunnel *tunnel = NULL; | |
1357 | struct socket *sock = NULL; | |
1358 | struct sock *sk = NULL; | |
1359 | ||
1360 | tunnel = container_of(work, struct l2tp_tunnel, del_work); | |
1361 | sk = l2tp_tunnel_sock_lookup(tunnel); | |
1362 | if (!sk) | |
1363 | return; | |
1364 | ||
1365 | sock = sk->sk_socket; | |
f8ccac0e | 1366 | |
02d13ed5 TP |
1367 | /* If the tunnel socket was created by userspace, then go through the |
1368 | * inet layer to shut the socket down, and let userspace close it. | |
1369 | * Otherwise, if we created the socket directly within the kernel, use | |
1370 | * the sk API to release it here. | |
167eb17e TP |
1371 | * In either case the tunnel resources are freed in the socket |
1372 | * destructor when the tunnel socket goes away. | |
f8ccac0e | 1373 | */ |
02d13ed5 TP |
1374 | if (tunnel->fd >= 0) { |
1375 | if (sock) | |
1376 | inet_shutdown(sock, 2); | |
167eb17e | 1377 | } else { |
02d13ed5 TP |
1378 | if (sock) |
1379 | kernel_sock_shutdown(sock, SHUT_RDWR); | |
1380 | sk_release_kernel(sk); | |
167eb17e | 1381 | } |
f8ccac0e TP |
1382 | |
1383 | l2tp_tunnel_sock_put(sk); | |
fd558d18 | 1384 | } |
fd558d18 | 1385 | |
789a4a2c JC |
1386 | /* Create a socket for the tunnel, if one isn't set up by |
1387 | * userspace. This is used for static tunnels where there is no | |
1388 | * managing L2TP daemon. | |
167eb17e TP |
1389 | * |
1390 | * Since we don't want these sockets to keep a namespace alive by | |
1391 | * themselves, we drop the socket's namespace refcount after creation. | |
1392 | * These sockets are freed when the namespace exits using the pernet | |
1393 | * exit hook. | |
789a4a2c | 1394 | */ |
167eb17e TP |
1395 | static int l2tp_tunnel_sock_create(struct net *net, |
1396 | u32 tunnel_id, | |
1397 | u32 peer_tunnel_id, | |
1398 | struct l2tp_tunnel_cfg *cfg, | |
1399 | struct socket **sockp) | |
789a4a2c JC |
1400 | { |
1401 | int err = -EINVAL; | |
167eb17e TP |
1402 | struct socket *sock = NULL; |
1403 | struct sockaddr_in udp_addr = {0}; | |
1404 | struct sockaddr_l2tpip ip_addr = {0}; | |
f9bac8df | 1405 | #if IS_ENABLED(CONFIG_IPV6) |
167eb17e TP |
1406 | struct sockaddr_in6 udp6_addr = {0}; |
1407 | struct sockaddr_l2tpip6 ip6_addr = {0}; | |
f9bac8df | 1408 | #endif |
789a4a2c JC |
1409 | |
1410 | switch (cfg->encap) { | |
1411 | case L2TP_ENCAPTYPE_UDP: | |
f9bac8df CE |
1412 | #if IS_ENABLED(CONFIG_IPV6) |
1413 | if (cfg->local_ip6 && cfg->peer_ip6) { | |
167eb17e | 1414 | err = sock_create_kern(AF_INET6, SOCK_DGRAM, 0, &sock); |
f9bac8df CE |
1415 | if (err < 0) |
1416 | goto out; | |
789a4a2c | 1417 | |
167eb17e | 1418 | sk_change_net(sock->sk, net); |
789a4a2c | 1419 | |
f9bac8df CE |
1420 | udp6_addr.sin6_family = AF_INET6; |
1421 | memcpy(&udp6_addr.sin6_addr, cfg->local_ip6, | |
1422 | sizeof(udp6_addr.sin6_addr)); | |
1423 | udp6_addr.sin6_port = htons(cfg->local_udp_port); | |
1424 | err = kernel_bind(sock, (struct sockaddr *) &udp6_addr, | |
1425 | sizeof(udp6_addr)); | |
1426 | if (err < 0) | |
1427 | goto out; | |
789a4a2c | 1428 | |
f9bac8df CE |
1429 | udp6_addr.sin6_family = AF_INET6; |
1430 | memcpy(&udp6_addr.sin6_addr, cfg->peer_ip6, | |
1431 | sizeof(udp6_addr.sin6_addr)); | |
1432 | udp6_addr.sin6_port = htons(cfg->peer_udp_port); | |
1433 | err = kernel_connect(sock, | |
1434 | (struct sockaddr *) &udp6_addr, | |
1435 | sizeof(udp6_addr), 0); | |
1436 | if (err < 0) | |
1437 | goto out; | |
1438 | } else | |
1439 | #endif | |
1440 | { | |
167eb17e | 1441 | err = sock_create_kern(AF_INET, SOCK_DGRAM, 0, &sock); |
f9bac8df CE |
1442 | if (err < 0) |
1443 | goto out; | |
1444 | ||
167eb17e | 1445 | sk_change_net(sock->sk, net); |
f9bac8df | 1446 | |
f9bac8df CE |
1447 | udp_addr.sin_family = AF_INET; |
1448 | udp_addr.sin_addr = cfg->local_ip; | |
1449 | udp_addr.sin_port = htons(cfg->local_udp_port); | |
1450 | err = kernel_bind(sock, (struct sockaddr *) &udp_addr, | |
1451 | sizeof(udp_addr)); | |
1452 | if (err < 0) | |
1453 | goto out; | |
1454 | ||
1455 | udp_addr.sin_family = AF_INET; | |
1456 | udp_addr.sin_addr = cfg->peer_ip; | |
1457 | udp_addr.sin_port = htons(cfg->peer_udp_port); | |
1458 | err = kernel_connect(sock, | |
1459 | (struct sockaddr *) &udp_addr, | |
1460 | sizeof(udp_addr), 0); | |
1461 | if (err < 0) | |
1462 | goto out; | |
1463 | } | |
789a4a2c JC |
1464 | |
1465 | if (!cfg->use_udp_checksums) | |
1466 | sock->sk->sk_no_check = UDP_CSUM_NOXMIT; | |
1467 | ||
1468 | break; | |
1469 | ||
1470 | case L2TP_ENCAPTYPE_IP: | |
f9bac8df CE |
1471 | #if IS_ENABLED(CONFIG_IPV6) |
1472 | if (cfg->local_ip6 && cfg->peer_ip6) { | |
167eb17e TP |
1473 | err = sock_create_kern(AF_INET6, SOCK_DGRAM, |
1474 | IPPROTO_L2TP, &sock); | |
5dac94e1 JC |
1475 | if (err < 0) |
1476 | goto out; | |
789a4a2c | 1477 | |
167eb17e | 1478 | sk_change_net(sock->sk, net); |
789a4a2c | 1479 | |
5dac94e1 JC |
1480 | ip6_addr.l2tp_family = AF_INET6; |
1481 | memcpy(&ip6_addr.l2tp_addr, cfg->local_ip6, | |
1482 | sizeof(ip6_addr.l2tp_addr)); | |
1483 | ip6_addr.l2tp_conn_id = tunnel_id; | |
1484 | err = kernel_bind(sock, (struct sockaddr *) &ip6_addr, | |
1485 | sizeof(ip6_addr)); | |
1486 | if (err < 0) | |
1487 | goto out; | |
789a4a2c | 1488 | |
5dac94e1 JC |
1489 | ip6_addr.l2tp_family = AF_INET6; |
1490 | memcpy(&ip6_addr.l2tp_addr, cfg->peer_ip6, | |
1491 | sizeof(ip6_addr.l2tp_addr)); | |
1492 | ip6_addr.l2tp_conn_id = peer_tunnel_id; | |
1493 | err = kernel_connect(sock, | |
1494 | (struct sockaddr *) &ip6_addr, | |
1495 | sizeof(ip6_addr), 0); | |
1496 | if (err < 0) | |
1497 | goto out; | |
1498 | } else | |
1499 | #endif | |
1500 | { | |
167eb17e TP |
1501 | err = sock_create_kern(AF_INET, SOCK_DGRAM, |
1502 | IPPROTO_L2TP, &sock); | |
5dac94e1 JC |
1503 | if (err < 0) |
1504 | goto out; | |
789a4a2c | 1505 | |
167eb17e | 1506 | sk_change_net(sock->sk, net); |
5dac94e1 | 1507 | |
5dac94e1 JC |
1508 | ip_addr.l2tp_family = AF_INET; |
1509 | ip_addr.l2tp_addr = cfg->local_ip; | |
1510 | ip_addr.l2tp_conn_id = tunnel_id; | |
1511 | err = kernel_bind(sock, (struct sockaddr *) &ip_addr, | |
1512 | sizeof(ip_addr)); | |
1513 | if (err < 0) | |
1514 | goto out; | |
1515 | ||
1516 | ip_addr.l2tp_family = AF_INET; | |
1517 | ip_addr.l2tp_addr = cfg->peer_ip; | |
1518 | ip_addr.l2tp_conn_id = peer_tunnel_id; | |
1519 | err = kernel_connect(sock, (struct sockaddr *) &ip_addr, | |
1520 | sizeof(ip_addr), 0); | |
1521 | if (err < 0) | |
1522 | goto out; | |
1523 | } | |
789a4a2c JC |
1524 | break; |
1525 | ||
1526 | default: | |
1527 | goto out; | |
1528 | } | |
1529 | ||
1530 | out: | |
167eb17e | 1531 | *sockp = sock; |
789a4a2c | 1532 | if ((err < 0) && sock) { |
167eb17e TP |
1533 | kernel_sock_shutdown(sock, SHUT_RDWR); |
1534 | sk_release_kernel(sock->sk); | |
789a4a2c JC |
1535 | *sockp = NULL; |
1536 | } | |
1537 | ||
1538 | return err; | |
1539 | } | |
1540 | ||
37159ef2 ED |
1541 | static struct lock_class_key l2tp_socket_class; |
1542 | ||
fd558d18 JC |
1543 | 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) |
1544 | { | |
1545 | struct l2tp_tunnel *tunnel = NULL; | |
1546 | int err; | |
1547 | struct socket *sock = NULL; | |
1548 | struct sock *sk = NULL; | |
1549 | struct l2tp_net *pn; | |
0d76751f | 1550 | enum l2tp_encap_type encap = L2TP_ENCAPTYPE_UDP; |
fd558d18 JC |
1551 | |
1552 | /* Get the tunnel socket from the fd, which was opened by | |
789a4a2c JC |
1553 | * the userspace L2TP daemon. If not specified, create a |
1554 | * kernel socket. | |
fd558d18 | 1555 | */ |
789a4a2c | 1556 | if (fd < 0) { |
167eb17e TP |
1557 | err = l2tp_tunnel_sock_create(net, tunnel_id, peer_tunnel_id, |
1558 | cfg, &sock); | |
789a4a2c JC |
1559 | if (err < 0) |
1560 | goto err; | |
1561 | } else { | |
789a4a2c JC |
1562 | sock = sockfd_lookup(fd, &err); |
1563 | if (!sock) { | |
cbb95e0c | 1564 | pr_err("tunl %u: sockfd_lookup(fd=%d) returned %d\n", |
789a4a2c | 1565 | tunnel_id, fd, err); |
cbb95e0c TP |
1566 | err = -EBADF; |
1567 | goto err; | |
1568 | } | |
1569 | ||
1570 | /* Reject namespace mismatches */ | |
1571 | if (!net_eq(sock_net(sock->sk), net)) { | |
1572 | pr_err("tunl %u: netns mismatch\n", tunnel_id); | |
1573 | err = -EINVAL; | |
789a4a2c JC |
1574 | goto err; |
1575 | } | |
fd558d18 JC |
1576 | } |
1577 | ||
1578 | sk = sock->sk; | |
1579 | ||
0d76751f JC |
1580 | if (cfg != NULL) |
1581 | encap = cfg->encap; | |
1582 | ||
fd558d18 | 1583 | /* Quick sanity checks */ |
0d76751f JC |
1584 | switch (encap) { |
1585 | case L2TP_ENCAPTYPE_UDP: | |
1586 | err = -EPROTONOSUPPORT; | |
1587 | if (sk->sk_protocol != IPPROTO_UDP) { | |
a4ca44fa | 1588 | pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", |
0d76751f JC |
1589 | tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP); |
1590 | goto err; | |
1591 | } | |
1592 | break; | |
1593 | case L2TP_ENCAPTYPE_IP: | |
1594 | err = -EPROTONOSUPPORT; | |
1595 | if (sk->sk_protocol != IPPROTO_L2TP) { | |
a4ca44fa | 1596 | pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", |
0d76751f JC |
1597 | tunnel_id, fd, sk->sk_protocol, IPPROTO_L2TP); |
1598 | goto err; | |
1599 | } | |
1600 | break; | |
fd558d18 JC |
1601 | } |
1602 | ||
1603 | /* Check if this socket has already been prepped */ | |
8d8a51e2 | 1604 | tunnel = l2tp_tunnel(sk); |
fd558d18 JC |
1605 | if (tunnel != NULL) { |
1606 | /* This socket has already been prepped */ | |
1607 | err = -EBUSY; | |
1608 | goto err; | |
1609 | } | |
1610 | ||
fd558d18 JC |
1611 | tunnel = kzalloc(sizeof(struct l2tp_tunnel), GFP_KERNEL); |
1612 | if (tunnel == NULL) { | |
1613 | err = -ENOMEM; | |
1614 | goto err; | |
1615 | } | |
1616 | ||
1617 | tunnel->version = version; | |
1618 | tunnel->tunnel_id = tunnel_id; | |
1619 | tunnel->peer_tunnel_id = peer_tunnel_id; | |
1620 | tunnel->debug = L2TP_DEFAULT_DEBUG_FLAGS; | |
1621 | ||
1622 | tunnel->magic = L2TP_TUNNEL_MAGIC; | |
1623 | sprintf(&tunnel->name[0], "tunl %u", tunnel_id); | |
1624 | rwlock_init(&tunnel->hlist_lock); | |
1625 | ||
1626 | /* The net we belong to */ | |
1627 | tunnel->l2tp_net = net; | |
1628 | pn = l2tp_pernet(net); | |
1629 | ||
0d76751f | 1630 | if (cfg != NULL) |
fd558d18 JC |
1631 | tunnel->debug = cfg->debug; |
1632 | ||
e18503f4 FC |
1633 | #if IS_ENABLED(CONFIG_IPV6) |
1634 | if (sk->sk_family == PF_INET6) { | |
1635 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1636 | ||
1637 | if (ipv6_addr_v4mapped(&np->saddr) && | |
efe4208f | 1638 | ipv6_addr_v4mapped(&sk->sk_v6_daddr)) { |
e18503f4 FC |
1639 | struct inet_sock *inet = inet_sk(sk); |
1640 | ||
1641 | tunnel->v4mapped = true; | |
1642 | inet->inet_saddr = np->saddr.s6_addr32[3]; | |
efe4208f ED |
1643 | inet->inet_rcv_saddr = sk->sk_v6_rcv_saddr.s6_addr32[3]; |
1644 | inet->inet_daddr = sk->sk_v6_daddr.s6_addr32[3]; | |
e18503f4 FC |
1645 | } else { |
1646 | tunnel->v4mapped = false; | |
1647 | } | |
1648 | } | |
1649 | #endif | |
1650 | ||
fd558d18 | 1651 | /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ |
0d76751f JC |
1652 | tunnel->encap = encap; |
1653 | if (encap == L2TP_ENCAPTYPE_UDP) { | |
1654 | /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ | |
1655 | udp_sk(sk)->encap_type = UDP_ENCAP_L2TPINUDP; | |
1656 | udp_sk(sk)->encap_rcv = l2tp_udp_encap_recv; | |
9980d001 | 1657 | udp_sk(sk)->encap_destroy = l2tp_udp_encap_destroy; |
d2cf3361 | 1658 | #if IS_ENABLED(CONFIG_IPV6) |
e18503f4 | 1659 | if (sk->sk_family == PF_INET6 && !tunnel->v4mapped) |
d2cf3361 BL |
1660 | udpv6_encap_enable(); |
1661 | else | |
1662 | #endif | |
447167bf | 1663 | udp_encap_enable(); |
0d76751f | 1664 | } |
fd558d18 JC |
1665 | |
1666 | sk->sk_user_data = tunnel; | |
1667 | ||
1668 | /* Hook on the tunnel socket destructor so that we can cleanup | |
1669 | * if the tunnel socket goes away. | |
1670 | */ | |
1671 | tunnel->old_sk_destruct = sk->sk_destruct; | |
1672 | sk->sk_destruct = &l2tp_tunnel_destruct; | |
1673 | tunnel->sock = sk; | |
80d84ef3 | 1674 | tunnel->fd = fd; |
37159ef2 ED |
1675 | lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class, "l2tp_sock"); |
1676 | ||
fd558d18 JC |
1677 | sk->sk_allocation = GFP_ATOMIC; |
1678 | ||
f8ccac0e TP |
1679 | /* Init delete workqueue struct */ |
1680 | INIT_WORK(&tunnel->del_work, l2tp_tunnel_del_work); | |
1681 | ||
fd558d18 JC |
1682 | /* Add tunnel to our list */ |
1683 | INIT_LIST_HEAD(&tunnel->list); | |
fd558d18 JC |
1684 | atomic_inc(&l2tp_tunnel_count); |
1685 | ||
1686 | /* Bump the reference count. The tunnel context is deleted | |
1769192a | 1687 | * only when this drops to zero. Must be done before list insertion |
fd558d18 JC |
1688 | */ |
1689 | l2tp_tunnel_inc_refcount(tunnel); | |
1769192a ED |
1690 | spin_lock_bh(&pn->l2tp_tunnel_list_lock); |
1691 | list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list); | |
1692 | spin_unlock_bh(&pn->l2tp_tunnel_list_lock); | |
fd558d18 JC |
1693 | |
1694 | err = 0; | |
1695 | err: | |
1696 | if (tunnelp) | |
1697 | *tunnelp = tunnel; | |
1698 | ||
789a4a2c JC |
1699 | /* If tunnel's socket was created by the kernel, it doesn't |
1700 | * have a file. | |
1701 | */ | |
1702 | if (sock && sock->file) | |
fd558d18 JC |
1703 | sockfd_put(sock); |
1704 | ||
1705 | return err; | |
1706 | } | |
1707 | EXPORT_SYMBOL_GPL(l2tp_tunnel_create); | |
1708 | ||
309795f4 JC |
1709 | /* This function is used by the netlink TUNNEL_DELETE command. |
1710 | */ | |
1711 | int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) | |
1712 | { | |
2b551c6e | 1713 | l2tp_tunnel_closeall(tunnel); |
f8ccac0e | 1714 | return (false == queue_work(l2tp_wq, &tunnel->del_work)); |
309795f4 JC |
1715 | } |
1716 | EXPORT_SYMBOL_GPL(l2tp_tunnel_delete); | |
1717 | ||
fd558d18 JC |
1718 | /* Really kill the session. |
1719 | */ | |
1720 | void l2tp_session_free(struct l2tp_session *session) | |
1721 | { | |
f6e16b29 | 1722 | struct l2tp_tunnel *tunnel = session->tunnel; |
fd558d18 JC |
1723 | |
1724 | BUG_ON(atomic_read(&session->ref_count) != 0); | |
1725 | ||
f6e16b29 | 1726 | if (tunnel) { |
fd558d18 | 1727 | BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); |
f6e16b29 TP |
1728 | if (session->session_id != 0) |
1729 | atomic_dec(&l2tp_session_count); | |
1730 | sock_put(tunnel->sock); | |
1731 | session->tunnel = NULL; | |
1732 | l2tp_tunnel_dec_refcount(tunnel); | |
1733 | } | |
1734 | ||
1735 | kfree(session); | |
f6e16b29 TP |
1736 | } |
1737 | EXPORT_SYMBOL_GPL(l2tp_session_free); | |
1738 | ||
1739 | /* Remove an l2tp session from l2tp_core's hash lists. | |
1740 | * Provides a tidyup interface for pseudowire code which can't just route all | |
1741 | * shutdown via. l2tp_session_delete and a pseudowire-specific session_close | |
1742 | * callback. | |
1743 | */ | |
1744 | void __l2tp_session_unhash(struct l2tp_session *session) | |
1745 | { | |
1746 | struct l2tp_tunnel *tunnel = session->tunnel; | |
fd558d18 | 1747 | |
f6e16b29 TP |
1748 | /* Remove the session from core hashes */ |
1749 | if (tunnel) { | |
1750 | /* Remove from the per-tunnel hash */ | |
fd558d18 JC |
1751 | write_lock_bh(&tunnel->hlist_lock); |
1752 | hlist_del_init(&session->hlist); | |
1753 | write_unlock_bh(&tunnel->hlist_lock); | |
1754 | ||
f6e16b29 | 1755 | /* For L2TPv3 we have a per-net hash: remove from there, too */ |
f7faffa3 JC |
1756 | if (tunnel->version != L2TP_HDR_VER_2) { |
1757 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); | |
e02d494d JC |
1758 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
1759 | hlist_del_init_rcu(&session->global_hlist); | |
1760 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); | |
1761 | synchronize_rcu(); | |
f7faffa3 | 1762 | } |
fd558d18 | 1763 | } |
fd558d18 | 1764 | } |
f6e16b29 | 1765 | EXPORT_SYMBOL_GPL(__l2tp_session_unhash); |
fd558d18 | 1766 | |
309795f4 JC |
1767 | /* This function is used by the netlink SESSION_DELETE command and by |
1768 | pseudowire modules. | |
1769 | */ | |
1770 | int l2tp_session_delete(struct l2tp_session *session) | |
1771 | { | |
f6e16b29 TP |
1772 | if (session->ref) |
1773 | (*session->ref)(session); | |
1774 | __l2tp_session_unhash(session); | |
4c6e2fd3 | 1775 | l2tp_session_queue_purge(session); |
309795f4 JC |
1776 | if (session->session_close != NULL) |
1777 | (*session->session_close)(session); | |
f6e16b29 | 1778 | if (session->deref) |
1b7c92b9 | 1779 | (*session->deref)(session); |
309795f4 | 1780 | l2tp_session_dec_refcount(session); |
309795f4 JC |
1781 | return 0; |
1782 | } | |
1783 | EXPORT_SYMBOL_GPL(l2tp_session_delete); | |
1784 | ||
f7faffa3 JC |
1785 | /* We come here whenever a session's send_seq, cookie_len or |
1786 | * l2specific_len parameters are set. | |
1787 | */ | |
bb5016ea | 1788 | void l2tp_session_set_header_len(struct l2tp_session *session, int version) |
f7faffa3 JC |
1789 | { |
1790 | if (version == L2TP_HDR_VER_2) { | |
1791 | session->hdr_len = 6; | |
1792 | if (session->send_seq) | |
1793 | session->hdr_len += 4; | |
1794 | } else { | |
0d76751f JC |
1795 | session->hdr_len = 4 + session->cookie_len + session->l2specific_len + session->offset; |
1796 | if (session->tunnel->encap == L2TP_ENCAPTYPE_UDP) | |
1797 | session->hdr_len += 4; | |
f7faffa3 JC |
1798 | } |
1799 | ||
1800 | } | |
bb5016ea | 1801 | EXPORT_SYMBOL_GPL(l2tp_session_set_header_len); |
f7faffa3 | 1802 | |
fd558d18 JC |
1803 | 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) |
1804 | { | |
1805 | struct l2tp_session *session; | |
1806 | ||
1807 | session = kzalloc(sizeof(struct l2tp_session) + priv_size, GFP_KERNEL); | |
1808 | if (session != NULL) { | |
1809 | session->magic = L2TP_SESSION_MAGIC; | |
1810 | session->tunnel = tunnel; | |
1811 | ||
1812 | session->session_id = session_id; | |
1813 | session->peer_session_id = peer_session_id; | |
d301e325 | 1814 | session->nr = 0; |
8a1631d5 JC |
1815 | if (tunnel->version == L2TP_HDR_VER_2) |
1816 | session->nr_max = 0xffff; | |
1817 | else | |
1818 | session->nr_max = 0xffffff; | |
1819 | session->nr_window_size = session->nr_max / 2; | |
a0dbd822 JC |
1820 | session->nr_oos_count_max = 4; |
1821 | ||
1822 | /* Use NR of first received packet */ | |
1823 | session->reorder_skip = 1; | |
fd558d18 JC |
1824 | |
1825 | sprintf(&session->name[0], "sess %u/%u", | |
1826 | tunnel->tunnel_id, session->session_id); | |
1827 | ||
1828 | skb_queue_head_init(&session->reorder_q); | |
1829 | ||
1830 | INIT_HLIST_NODE(&session->hlist); | |
f7faffa3 | 1831 | INIT_HLIST_NODE(&session->global_hlist); |
fd558d18 JC |
1832 | |
1833 | /* Inherit debug options from tunnel */ | |
1834 | session->debug = tunnel->debug; | |
1835 | ||
1836 | if (cfg) { | |
f7faffa3 | 1837 | session->pwtype = cfg->pw_type; |
fd558d18 | 1838 | session->debug = cfg->debug; |
fd558d18 JC |
1839 | session->mtu = cfg->mtu; |
1840 | session->mru = cfg->mru; | |
1841 | session->send_seq = cfg->send_seq; | |
1842 | session->recv_seq = cfg->recv_seq; | |
1843 | session->lns_mode = cfg->lns_mode; | |
f7faffa3 JC |
1844 | session->reorder_timeout = cfg->reorder_timeout; |
1845 | session->offset = cfg->offset; | |
1846 | session->l2specific_type = cfg->l2specific_type; | |
1847 | session->l2specific_len = cfg->l2specific_len; | |
1848 | session->cookie_len = cfg->cookie_len; | |
1849 | memcpy(&session->cookie[0], &cfg->cookie[0], cfg->cookie_len); | |
1850 | session->peer_cookie_len = cfg->peer_cookie_len; | |
1851 | memcpy(&session->peer_cookie[0], &cfg->peer_cookie[0], cfg->peer_cookie_len); | |
fd558d18 JC |
1852 | } |
1853 | ||
f7faffa3 JC |
1854 | if (tunnel->version == L2TP_HDR_VER_2) |
1855 | session->build_header = l2tp_build_l2tpv2_header; | |
1856 | else | |
1857 | session->build_header = l2tp_build_l2tpv3_header; | |
1858 | ||
1859 | l2tp_session_set_header_len(session, tunnel->version); | |
1860 | ||
fd558d18 JC |
1861 | /* Bump the reference count. The session context is deleted |
1862 | * only when this drops to zero. | |
1863 | */ | |
1864 | l2tp_session_inc_refcount(session); | |
1865 | l2tp_tunnel_inc_refcount(tunnel); | |
1866 | ||
1867 | /* Ensure tunnel socket isn't deleted */ | |
1868 | sock_hold(tunnel->sock); | |
1869 | ||
1870 | /* Add session to the tunnel's hash list */ | |
1871 | write_lock_bh(&tunnel->hlist_lock); | |
1872 | hlist_add_head(&session->hlist, | |
1873 | l2tp_session_id_hash(tunnel, session_id)); | |
1874 | write_unlock_bh(&tunnel->hlist_lock); | |
1875 | ||
f7faffa3 JC |
1876 | /* And to the global session list if L2TPv3 */ |
1877 | if (tunnel->version != L2TP_HDR_VER_2) { | |
1878 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); | |
1879 | ||
e02d494d JC |
1880 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
1881 | hlist_add_head_rcu(&session->global_hlist, | |
1882 | l2tp_session_id_hash_2(pn, session_id)); | |
1883 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); | |
f7faffa3 JC |
1884 | } |
1885 | ||
fd558d18 JC |
1886 | /* Ignore management session in session count value */ |
1887 | if (session->session_id != 0) | |
1888 | atomic_inc(&l2tp_session_count); | |
1889 | } | |
1890 | ||
1891 | return session; | |
1892 | } | |
1893 | EXPORT_SYMBOL_GPL(l2tp_session_create); | |
1894 | ||
1895 | /***************************************************************************** | |
1896 | * Init and cleanup | |
1897 | *****************************************************************************/ | |
1898 | ||
1899 | static __net_init int l2tp_init_net(struct net *net) | |
1900 | { | |
e773aaff | 1901 | struct l2tp_net *pn = net_generic(net, l2tp_net_id); |
f7faffa3 | 1902 | int hash; |
fd558d18 | 1903 | |
fd558d18 | 1904 | INIT_LIST_HEAD(&pn->l2tp_tunnel_list); |
e02d494d | 1905 | spin_lock_init(&pn->l2tp_tunnel_list_lock); |
fd558d18 | 1906 | |
f7faffa3 JC |
1907 | for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) |
1908 | INIT_HLIST_HEAD(&pn->l2tp_session_hlist[hash]); | |
1909 | ||
e02d494d | 1910 | spin_lock_init(&pn->l2tp_session_hlist_lock); |
f7faffa3 | 1911 | |
fd558d18 | 1912 | return 0; |
fd558d18 JC |
1913 | } |
1914 | ||
167eb17e TP |
1915 | static __net_exit void l2tp_exit_net(struct net *net) |
1916 | { | |
1917 | struct l2tp_net *pn = l2tp_pernet(net); | |
1918 | struct l2tp_tunnel *tunnel = NULL; | |
1919 | ||
1920 | rcu_read_lock_bh(); | |
1921 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { | |
1922 | (void)l2tp_tunnel_delete(tunnel); | |
1923 | } | |
1924 | rcu_read_unlock_bh(); | |
1925 | } | |
1926 | ||
fd558d18 JC |
1927 | static struct pernet_operations l2tp_net_ops = { |
1928 | .init = l2tp_init_net, | |
167eb17e | 1929 | .exit = l2tp_exit_net, |
fd558d18 JC |
1930 | .id = &l2tp_net_id, |
1931 | .size = sizeof(struct l2tp_net), | |
1932 | }; | |
1933 | ||
1934 | static int __init l2tp_init(void) | |
1935 | { | |
1936 | int rc = 0; | |
1937 | ||
1938 | rc = register_pernet_device(&l2tp_net_ops); | |
1939 | if (rc) | |
1940 | goto out; | |
1941 | ||
59ff3eb6 | 1942 | l2tp_wq = alloc_workqueue("l2tp", WQ_UNBOUND, 0); |
f8ccac0e TP |
1943 | if (!l2tp_wq) { |
1944 | pr_err("alloc_workqueue failed\n"); | |
1945 | rc = -ENOMEM; | |
1946 | goto out; | |
1947 | } | |
1948 | ||
a4ca44fa | 1949 | pr_info("L2TP core driver, %s\n", L2TP_DRV_VERSION); |
fd558d18 JC |
1950 | |
1951 | out: | |
1952 | return rc; | |
1953 | } | |
1954 | ||
1955 | static void __exit l2tp_exit(void) | |
1956 | { | |
1957 | unregister_pernet_device(&l2tp_net_ops); | |
f8ccac0e TP |
1958 | if (l2tp_wq) { |
1959 | destroy_workqueue(l2tp_wq); | |
1960 | l2tp_wq = NULL; | |
1961 | } | |
fd558d18 JC |
1962 | } |
1963 | ||
1964 | module_init(l2tp_init); | |
1965 | module_exit(l2tp_exit); | |
1966 | ||
1967 | MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); | |
1968 | MODULE_DESCRIPTION("L2TP core"); | |
1969 | MODULE_LICENSE("GPL"); | |
1970 | MODULE_VERSION(L2TP_DRV_VERSION); | |
1971 |