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firmware_class: fix memory leak - free allocated pages
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / net / pppol2tp.c
blobb724d7faa3c8bad73241c5c6d76f6509f5bd289b
1 /*****************************************************************************
2 * Linux PPP over L2TP (PPPoX/PPPoL2TP) Sockets
3 *
4 * PPPoX --- Generic PPP encapsulation socket family
5 * PPPoL2TP --- PPP over L2TP (RFC 2661)
6 *
7 * Version: 1.0.0
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 * License:
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
21 *
22 */
23
24 /* This driver handles only L2TP data frames; control frames are handled by a
25 * userspace application.
26 *
27 * To send data in an L2TP session, userspace opens a PPPoL2TP socket and
28 * attaches it to a bound UDP socket with local tunnel_id / session_id and
29 * peer tunnel_id / session_id set. Data can then be sent or received using
30 * regular socket sendmsg() / recvmsg() calls. Kernel parameters of the socket
31 * can be read or modified using ioctl() or [gs]etsockopt() calls.
32 *
33 * When a PPPoL2TP socket is connected with local and peer session_id values
34 * zero, the socket is treated as a special tunnel management socket.
35 *
36 * Here's example userspace code to create a socket for sending/receiving data
37 * over an L2TP session:-
38 *
39 * struct sockaddr_pppol2tp sax;
40 * int fd;
41 * int session_fd;
42 *
43 * fd = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP);
44 *
45 * sax.sa_family = AF_PPPOX;
46 * sax.sa_protocol = PX_PROTO_OL2TP;
47 * sax.pppol2tp.fd = tunnel_fd; // bound UDP socket
48 * sax.pppol2tp.addr.sin_addr.s_addr = addr->sin_addr.s_addr;
49 * sax.pppol2tp.addr.sin_port = addr->sin_port;
50 * sax.pppol2tp.addr.sin_family = AF_INET;
51 * sax.pppol2tp.s_tunnel = tunnel_id;
52 * sax.pppol2tp.s_session = session_id;
53 * sax.pppol2tp.d_tunnel = peer_tunnel_id;
54 * sax.pppol2tp.d_session = peer_session_id;
55 *
56 * session_fd = connect(fd, (struct sockaddr *)&sax, sizeof(sax));
57 *
58 * A pppd plugin that allows PPP traffic to be carried over L2TP using
59 * this driver is available from the OpenL2TP project at
60 * http://openl2tp.sourceforge.net.
61 */
62
63 #include <linux/module.h>
64 #include <linux/string.h>
65 #include <linux/list.h>
66 #include <asm/uaccess.h>
67
68 #include <linux/kernel.h>
69 #include <linux/spinlock.h>
70 #include <linux/kthread.h>
71 #include <linux/sched.h>
72 #include <linux/slab.h>
73 #include <linux/errno.h>
74 #include <linux/jiffies.h>
75
76 #include <linux/netdevice.h>
77 #include <linux/net.h>
78 #include <linux/inetdevice.h>
79 #include <linux/skbuff.h>
80 #include <linux/init.h>
81 #include <linux/ip.h>
82 #include <linux/udp.h>
83 #include <linux/if_pppox.h>
84 #include <linux/if_pppol2tp.h>
85 #include <net/sock.h>
86 #include <linux/ppp_channel.h>
87 #include <linux/ppp_defs.h>
88 #include <linux/if_ppp.h>
89 #include <linux/file.h>
90 #include <linux/hash.h>
91 #include <linux/sort.h>
92 #include <linux/proc_fs.h>
93 #include <linux/nsproxy.h>
94 #include <net/net_namespace.h>
95 #include <net/netns/generic.h>
96 #include <net/dst.h>
97 #include <net/ip.h>
98 #include <net/udp.h>
99 #include <net/xfrm.h>
100
101 #include <asm/byteorder.h>
102 #include <asm/atomic.h>
103
104
105 #define PPPOL2TP_DRV_VERSION "V1.0"
106
107 /* L2TP header constants */
108 #define L2TP_HDRFLAG_T 0x8000
109 #define L2TP_HDRFLAG_L 0x4000
110 #define L2TP_HDRFLAG_S 0x0800
111 #define L2TP_HDRFLAG_O 0x0200
112 #define L2TP_HDRFLAG_P 0x0100
113
114 #define L2TP_HDR_VER_MASK 0x000F
115 #define L2TP_HDR_VER 0x0002
116
117 /* Space for UDP, L2TP and PPP headers */
118 #define PPPOL2TP_HEADER_OVERHEAD 40
119
120 /* Just some random numbers */
121 #define L2TP_TUNNEL_MAGIC 0x42114DDA
122 #define L2TP_SESSION_MAGIC 0x0C04EB7D
123
124 #define PPPOL2TP_HASH_BITS 4
125 #define PPPOL2TP_HASH_SIZE (1 << PPPOL2TP_HASH_BITS)
126
127 /* Default trace flags */
128 #define PPPOL2TP_DEFAULT_DEBUG_FLAGS 0
129
130 #define PRINTK(_mask, _type, _lvl, _fmt, args...) \
131 do { \
132 if ((_mask) & (_type)) \
133 printk(_lvl "PPPOL2TP: " _fmt, ##args); \
134 } while(0)
135
136 /* Number of bytes to build transmit L2TP headers.
137 * Unfortunately the size is different depending on whether sequence numbers
138 * are enabled.
139 */
140 #define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10
141 #define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6
142
143 struct pppol2tp_tunnel;
144
145 /* Describes a session. It is the sk_user_data field in the PPPoL2TP
146 * socket. Contains information to determine incoming packets and transmit
147 * outgoing ones.
148 */
149 struct pppol2tp_session
150 {
151 int magic; /* should be
152 * L2TP_SESSION_MAGIC */
153 int owner; /* pid that opened the socket */
154
155 struct sock *sock; /* Pointer to the session
156 * PPPoX socket */
157 struct sock *tunnel_sock; /* Pointer to the tunnel UDP
158 * socket */
159
160 struct pppol2tp_addr tunnel_addr; /* Description of tunnel */
161
162 struct pppol2tp_tunnel *tunnel; /* back pointer to tunnel
163 * context */
164
165 char name[20]; /* "sess xxxxx/yyyyy", where
166 * x=tunnel_id, y=session_id */
167 int mtu;
168 int mru;
169 int flags; /* accessed by PPPIOCGFLAGS.
170 * Unused. */
171 unsigned recv_seq:1; /* expect receive packets with
172 * sequence numbers? */
173 unsigned send_seq:1; /* send packets with sequence
174 * numbers? */
175 unsigned lns_mode:1; /* behave as LNS? LAC enables
176 * sequence numbers under
177 * control of LNS. */
178 int debug; /* bitmask of debug message
179 * categories */
180 int reorder_timeout; /* configured reorder timeout
181 * (in jiffies) */
182 u16 nr; /* session NR state (receive) */
183 u16 ns; /* session NR state (send) */
184 struct sk_buff_head reorder_q; /* receive reorder queue */
185 struct pppol2tp_ioc_stats stats;
186 struct hlist_node hlist; /* Hash list node */
187 };
188
189 /* The sk_user_data field of the tunnel's UDP socket. It contains info to track
190 * all the associated sessions so incoming packets can be sorted out
191 */
192 struct pppol2tp_tunnel
193 {
194 int magic; /* Should be L2TP_TUNNEL_MAGIC */
195 rwlock_t hlist_lock; /* protect session_hlist */
196 struct hlist_head session_hlist[PPPOL2TP_HASH_SIZE];
197 /* hashed list of sessions,
198 * hashed by id */
199 int debug; /* bitmask of debug message
200 * categories */
201 char name[12]; /* "tunl xxxxx" */
202 struct pppol2tp_ioc_stats stats;
203
204 void (*old_sk_destruct)(struct sock *);
205
206 struct sock *sock; /* Parent socket */
207 struct list_head list; /* Keep a list of all open
208 * prepared sockets */
209 struct net *pppol2tp_net; /* the net we belong to */
210
211 atomic_t ref_count;
212 };
213
214 /* Private data stored for received packets in the skb.
215 */
216 struct pppol2tp_skb_cb {
217 u16 ns;
218 u16 nr;
219 u16 has_seq;
220 u16 length;
221 unsigned long expires;
222 };
223
224 #define PPPOL2TP_SKB_CB(skb) ((struct pppol2tp_skb_cb *) &skb->cb[sizeof(struct inet_skb_parm)])
225
226 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb);
227 static void pppol2tp_tunnel_free(struct pppol2tp_tunnel *tunnel);
228
229 static atomic_t pppol2tp_tunnel_count;
230 static atomic_t pppol2tp_session_count;
231 static struct ppp_channel_ops pppol2tp_chan_ops = { pppol2tp_xmit , NULL };
232 static const struct proto_ops pppol2tp_ops;
233
234 /* per-net private data for this module */
235 static int pppol2tp_net_id;
236 struct pppol2tp_net {
237 struct list_head pppol2tp_tunnel_list;
238 rwlock_t pppol2tp_tunnel_list_lock;
239 };
240
241 static inline struct pppol2tp_net *pppol2tp_pernet(struct net *net)
242 {
243 BUG_ON(!net);
244
245 return net_generic(net, pppol2tp_net_id);
246 }
247
248 /* Helpers to obtain tunnel/session contexts from sockets.
249 */
250 static inline struct pppol2tp_session *pppol2tp_sock_to_session(struct sock *sk)
251 {
252 struct pppol2tp_session *session;
253
254 if (sk == NULL)
255 return NULL;
256
257 sock_hold(sk);
258 session = (struct pppol2tp_session *)(sk->sk_user_data);
259 if (session == NULL) {
260 sock_put(sk);
261 goto out;
262 }
263
264 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
265 out:
266 return session;
267 }
268
269 static inline struct pppol2tp_tunnel *pppol2tp_sock_to_tunnel(struct sock *sk)
270 {
271 struct pppol2tp_tunnel *tunnel;
272
273 if (sk == NULL)
274 return NULL;
275
276 sock_hold(sk);
277 tunnel = (struct pppol2tp_tunnel *)(sk->sk_user_data);
278 if (tunnel == NULL) {
279 sock_put(sk);
280 goto out;
281 }
282
283 BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
284 out:
285 return tunnel;
286 }
287
288 /* Tunnel reference counts. Incremented per session that is added to
289 * the tunnel.
290 */
291 static inline void pppol2tp_tunnel_inc_refcount(struct pppol2tp_tunnel *tunnel)
292 {
293 atomic_inc(&tunnel->ref_count);
294 }
295
296 static inline void pppol2tp_tunnel_dec_refcount(struct pppol2tp_tunnel *tunnel)
297 {
298 if (atomic_dec_and_test(&tunnel->ref_count))
299 pppol2tp_tunnel_free(tunnel);
300 }
301
302 /* Session hash list.
303 * The session_id SHOULD be random according to RFC2661, but several
304 * L2TP implementations (Cisco and Microsoft) use incrementing
305 * session_ids. So we do a real hash on the session_id, rather than a
306 * simple bitmask.
307 */
308 static inline struct hlist_head *
309 pppol2tp_session_id_hash(struct pppol2tp_tunnel *tunnel, u16 session_id)
310 {
311 unsigned long hash_val = (unsigned long) session_id;
312 return &tunnel->session_hlist[hash_long(hash_val, PPPOL2TP_HASH_BITS)];
313 }
314
315 /* Lookup a session by id
316 */
317 static struct pppol2tp_session *
318 pppol2tp_session_find(struct pppol2tp_tunnel *tunnel, u16 session_id)
319 {
320 struct hlist_head *session_list =
321 pppol2tp_session_id_hash(tunnel, session_id);
322 struct pppol2tp_session *session;
323 struct hlist_node *walk;
324
325 read_lock_bh(&tunnel->hlist_lock);
326 hlist_for_each_entry(session, walk, session_list, hlist) {
327 if (session->tunnel_addr.s_session == session_id) {
328 read_unlock_bh(&tunnel->hlist_lock);
329 return session;
330 }
331 }
332 read_unlock_bh(&tunnel->hlist_lock);
333
334 return NULL;
335 }
336
337 /* Lookup a tunnel by id
338 */
339 static struct pppol2tp_tunnel *pppol2tp_tunnel_find(struct net *net, u16 tunnel_id)
340 {
341 struct pppol2tp_tunnel *tunnel;
342 struct pppol2tp_net *pn = pppol2tp_pernet(net);
343
344 read_lock_bh(&pn->pppol2tp_tunnel_list_lock);
345 list_for_each_entry(tunnel, &pn->pppol2tp_tunnel_list, list) {
346 if (tunnel->stats.tunnel_id == tunnel_id) {
347 read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
348 return tunnel;
349 }
350 }
351 read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
352
353 return NULL;
354 }
355
356 /*****************************************************************************
357 * Receive data handling
358 *****************************************************************************/
359
360 /* Queue a skb in order. We come here only if the skb has an L2TP sequence
361 * number.
362 */
363 static void pppol2tp_recv_queue_skb(struct pppol2tp_session *session, struct sk_buff *skb)
364 {
365 struct sk_buff *skbp;
366 struct sk_buff *tmp;
367 u16 ns = PPPOL2TP_SKB_CB(skb)->ns;
368
369 spin_lock_bh(&session->reorder_q.lock);
370 skb_queue_walk_safe(&session->reorder_q, skbp, tmp) {
371 if (PPPOL2TP_SKB_CB(skbp)->ns > ns) {
372 __skb_queue_before(&session->reorder_q, skbp, skb);
373 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
374 "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n",
375 session->name, ns, PPPOL2TP_SKB_CB(skbp)->ns,
376 skb_queue_len(&session->reorder_q));
377 session->stats.rx_oos_packets++;
378 goto out;
379 }
380 }
381
382 __skb_queue_tail(&session->reorder_q, skb);
383
384 out:
385 spin_unlock_bh(&session->reorder_q.lock);
386 }
387
388 /* Dequeue a single skb.
389 */
390 static void pppol2tp_recv_dequeue_skb(struct pppol2tp_session *session, struct sk_buff *skb)
391 {
392 struct pppol2tp_tunnel *tunnel = session->tunnel;
393 int length = PPPOL2TP_SKB_CB(skb)->length;
394 struct sock *session_sock = NULL;
395
396 /* We're about to requeue the skb, so return resources
397 * to its current owner (a socket receive buffer).
398 */
399 skb_orphan(skb);
400
401 tunnel->stats.rx_packets++;
402 tunnel->stats.rx_bytes += length;
403 session->stats.rx_packets++;
404 session->stats.rx_bytes += length;
405
406 if (PPPOL2TP_SKB_CB(skb)->has_seq) {
407 /* Bump our Nr */
408 session->nr++;
409 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
410 "%s: updated nr to %hu\n", session->name, session->nr);
411 }
412
413 /* If the socket is bound, send it in to PPP's input queue. Otherwise
414 * queue it on the session socket.
415 */
416 session_sock = session->sock;
417 if (session_sock->sk_state & PPPOX_BOUND) {
418 struct pppox_sock *po;
419 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
420 "%s: recv %d byte data frame, passing to ppp\n",
421 session->name, length);
422
423 /* We need to forget all info related to the L2TP packet
424 * gathered in the skb as we are going to reuse the same
425 * skb for the inner packet.
426 * Namely we need to:
427 * - reset xfrm (IPSec) information as it applies to
428 * the outer L2TP packet and not to the inner one
429 * - release the dst to force a route lookup on the inner
430 * IP packet since skb->dst currently points to the dst
431 * of the UDP tunnel
432 * - reset netfilter information as it doesn't apply
433 * to the inner packet either
434 */
435 secpath_reset(skb);
436 skb_dst_drop(skb);
437 nf_reset(skb);
438
439 po = pppox_sk(session_sock);
440 ppp_input(&po->chan, skb);
441 } else {
442 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_INFO,
443 "%s: socket not bound\n", session->name);
444
445 /* Not bound. Nothing we can do, so discard. */
446 session->stats.rx_errors++;
447 kfree_skb(skb);
448 }
449
450 sock_put(session->sock);
451 }
452
453 /* Dequeue skbs from the session's reorder_q, subject to packet order.
454 * Skbs that have been in the queue for too long are simply discarded.
455 */
456 static void pppol2tp_recv_dequeue(struct pppol2tp_session *session)
457 {
458 struct sk_buff *skb;
459 struct sk_buff *tmp;
460
461 /* If the pkt at the head of the queue has the nr that we
462 * expect to send up next, dequeue it and any other
463 * in-sequence packets behind it.
464 */
465 spin_lock_bh(&session->reorder_q.lock);
466 skb_queue_walk_safe(&session->reorder_q, skb, tmp) {
467 if (time_after(jiffies, PPPOL2TP_SKB_CB(skb)->expires)) {
468 session->stats.rx_seq_discards++;
469 session->stats.rx_errors++;
470 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
471 "%s: oos pkt %hu len %d discarded (too old), "
472 "waiting for %hu, reorder_q_len=%d\n",
473 session->name, PPPOL2TP_SKB_CB(skb)->ns,
474 PPPOL2TP_SKB_CB(skb)->length, session->nr,
475 skb_queue_len(&session->reorder_q));
476 __skb_unlink(skb, &session->reorder_q);
477 kfree_skb(skb);
478 sock_put(session->sock);
479 continue;
480 }
481
482 if (PPPOL2TP_SKB_CB(skb)->has_seq) {
483 if (PPPOL2TP_SKB_CB(skb)->ns != session->nr) {
484 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
485 "%s: holding oos pkt %hu len %d, "
486 "waiting for %hu, reorder_q_len=%d\n",
487 session->name, PPPOL2TP_SKB_CB(skb)->ns,
488 PPPOL2TP_SKB_CB(skb)->length, session->nr,
489 skb_queue_len(&session->reorder_q));
490 goto out;
491 }
492 }
493 __skb_unlink(skb, &session->reorder_q);
494
495 /* Process the skb. We release the queue lock while we
496 * do so to let other contexts process the queue.
497 */
498 spin_unlock_bh(&session->reorder_q.lock);
499 pppol2tp_recv_dequeue_skb(session, skb);
500 spin_lock_bh(&session->reorder_q.lock);
501 }
502
503 out:
504 spin_unlock_bh(&session->reorder_q.lock);
505 }
506
507 static inline int pppol2tp_verify_udp_checksum(struct sock *sk,
508 struct sk_buff *skb)
509 {
510 struct udphdr *uh = udp_hdr(skb);
511 u16 ulen = ntohs(uh->len);
512 struct inet_sock *inet;
513 __wsum psum;
514
515 if (sk->sk_no_check || skb_csum_unnecessary(skb) || !uh->check)
516 return 0;
517
518 inet = inet_sk(sk);
519 psum = csum_tcpudp_nofold(inet->saddr, inet->daddr, ulen,
520 IPPROTO_UDP, 0);
521
522 if ((skb->ip_summed == CHECKSUM_COMPLETE) &&
523 !csum_fold(csum_add(psum, skb->csum)))
524 return 0;
525
526 skb->csum = psum;
527
528 return __skb_checksum_complete(skb);
529 }
530
531 /* Internal receive frame. Do the real work of receiving an L2TP data frame
532 * here. The skb is not on a list when we get here.
533 * Returns 0 if the packet was a data packet and was successfully passed on.
534 * Returns 1 if the packet was not a good data packet and could not be
535 * forwarded. All such packets are passed up to userspace to deal with.
536 */
537 static int pppol2tp_recv_core(struct sock *sock, struct sk_buff *skb)
538 {
539 struct pppol2tp_session *session = NULL;
540 struct pppol2tp_tunnel *tunnel;
541 unsigned char *ptr, *optr;
542 u16 hdrflags;
543 u16 tunnel_id, session_id;
544 int length;
545 int offset;
546
547 tunnel = pppol2tp_sock_to_tunnel(sock);
548 if (tunnel == NULL)
549 goto no_tunnel;
550
551 if (tunnel->sock && pppol2tp_verify_udp_checksum(tunnel->sock, skb))
552 goto discard_bad_csum;
553
554 /* UDP always verifies the packet length. */
555 __skb_pull(skb, sizeof(struct udphdr));
556
557 /* Short packet? */
558 if (!pskb_may_pull(skb, 12)) {
559 PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_INFO,
560 "%s: recv short packet (len=%d)\n", tunnel->name, skb->len);
561 goto error;
562 }
563
564 /* Point to L2TP header */
565 optr = ptr = skb->data;
566
567 /* Get L2TP header flags */
568 hdrflags = ntohs(*(__be16*)ptr);
569
570 /* Trace packet contents, if enabled */
571 if (tunnel->debug & PPPOL2TP_MSG_DATA) {
572 length = min(16u, skb->len);
573 if (!pskb_may_pull(skb, length))
574 goto error;
575
576 printk(KERN_DEBUG "%s: recv: ", tunnel->name);
577
578 offset = 0;
579 do {
580 printk(" %02X", ptr[offset]);
581 } while (++offset < length);
582
583 printk("\n");
584 }
585
586 /* Get length of L2TP packet */
587 length = skb->len;
588
589 /* If type is control packet, it is handled by userspace. */
590 if (hdrflags & L2TP_HDRFLAG_T) {
591 PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
592 "%s: recv control packet, len=%d\n", tunnel->name, length);
593 goto error;
594 }
595
596 /* Skip flags */
597 ptr += 2;
598
599 /* If length is present, skip it */
600 if (hdrflags & L2TP_HDRFLAG_L)
601 ptr += 2;
602
603 /* Extract tunnel and session ID */
604 tunnel_id = ntohs(*(__be16 *) ptr);
605 ptr += 2;
606 session_id = ntohs(*(__be16 *) ptr);
607 ptr += 2;
608
609 /* Find the session context */
610 session = pppol2tp_session_find(tunnel, session_id);
611 if (!session) {
612 /* Not found? Pass to userspace to deal with */
613 PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_INFO,
614 "%s: no socket found (%hu/%hu). Passing up.\n",
615 tunnel->name, tunnel_id, session_id);
616 goto error;
617 }
618 sock_hold(session->sock);
619
620 /* The ref count on the socket was increased by the above call since
621 * we now hold a pointer to the session. Take care to do sock_put()
622 * when exiting this function from now on...
623 */
624
625 /* Handle the optional sequence numbers. If we are the LAC,
626 * enable/disable sequence numbers under the control of the LNS. If
627 * no sequence numbers present but we were expecting them, discard
628 * frame.
629 */
630 if (hdrflags & L2TP_HDRFLAG_S) {
631 u16 ns, nr;
632 ns = ntohs(*(__be16 *) ptr);
633 ptr += 2;
634 nr = ntohs(*(__be16 *) ptr);
635 ptr += 2;
636
637 /* Received a packet with sequence numbers. If we're the LNS,
638 * check if we sre sending sequence numbers and if not,
639 * configure it so.
640 */
641 if ((!session->lns_mode) && (!session->send_seq)) {
642 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_INFO,
643 "%s: requested to enable seq numbers by LNS\n",
644 session->name);
645 session->send_seq = -1;
646 }
647
648 /* Store L2TP info in the skb */
649 PPPOL2TP_SKB_CB(skb)->ns = ns;
650 PPPOL2TP_SKB_CB(skb)->nr = nr;
651 PPPOL2TP_SKB_CB(skb)->has_seq = 1;
652
653 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
654 "%s: recv data ns=%hu, nr=%hu, session nr=%hu\n",
655 session->name, ns, nr, session->nr);
656 } else {
657 /* No sequence numbers.
658 * If user has configured mandatory sequence numbers, discard.
659 */
660 if (session->recv_seq) {
661 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_WARNING,
662 "%s: recv data has no seq numbers when required. "
663 "Discarding\n", session->name);
664 session->stats.rx_seq_discards++;
665 goto discard;
666 }
667
668 /* If we're the LAC and we're sending sequence numbers, the
669 * LNS has requested that we no longer send sequence numbers.
670 * If we're the LNS and we're sending sequence numbers, the
671 * LAC is broken. Discard the frame.
672 */
673 if ((!session->lns_mode) && (session->send_seq)) {
674 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_INFO,
675 "%s: requested to disable seq numbers by LNS\n",
676 session->name);
677 session->send_seq = 0;
678 } else if (session->send_seq) {
679 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_WARNING,
680 "%s: recv data has no seq numbers when required. "
681 "Discarding\n", session->name);
682 session->stats.rx_seq_discards++;
683 goto discard;
684 }
685
686 /* Store L2TP info in the skb */
687 PPPOL2TP_SKB_CB(skb)->has_seq = 0;
688 }
689
690 /* If offset bit set, skip it. */
691 if (hdrflags & L2TP_HDRFLAG_O) {
692 offset = ntohs(*(__be16 *)ptr);
693 ptr += 2 + offset;
694 }
695
696 offset = ptr - optr;
697 if (!pskb_may_pull(skb, offset))
698 goto discard;
699
700 __skb_pull(skb, offset);
701
702 /* Skip PPP header, if present. In testing, Microsoft L2TP clients
703 * don't send the PPP header (PPP header compression enabled), but
704 * other clients can include the header. So we cope with both cases
705 * here. The PPP header is always FF03 when using L2TP.
706 *
707 * Note that skb->data[] isn't dereferenced from a u16 ptr here since
708 * the field may be unaligned.
709 */
710 if (!pskb_may_pull(skb, 2))
711 goto discard;
712
713 if ((skb->data[0] == 0xff) && (skb->data[1] == 0x03))
714 skb_pull(skb, 2);
715
716 /* Prepare skb for adding to the session's reorder_q. Hold
717 * packets for max reorder_timeout or 1 second if not
718 * reordering.
719 */
720 PPPOL2TP_SKB_CB(skb)->length = length;
721 PPPOL2TP_SKB_CB(skb)->expires = jiffies +
722 (session->reorder_timeout ? session->reorder_timeout : HZ);
723
724 /* Add packet to the session's receive queue. Reordering is done here, if
725 * enabled. Saved L2TP protocol info is stored in skb->sb[].
726 */
727 if (PPPOL2TP_SKB_CB(skb)->has_seq) {
728 if (session->reorder_timeout != 0) {
729 /* Packet reordering enabled. Add skb to session's
730 * reorder queue, in order of ns.
731 */
732 pppol2tp_recv_queue_skb(session, skb);
733 } else {
734 /* Packet reordering disabled. Discard out-of-sequence
735 * packets
736 */
737 if (PPPOL2TP_SKB_CB(skb)->ns != session->nr) {
738 session->stats.rx_seq_discards++;
739 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
740 "%s: oos pkt %hu len %d discarded, "
741 "waiting for %hu, reorder_q_len=%d\n",
742 session->name, PPPOL2TP_SKB_CB(skb)->ns,
743 PPPOL2TP_SKB_CB(skb)->length, session->nr,
744 skb_queue_len(&session->reorder_q));
745 goto discard;
746 }
747 skb_queue_tail(&session->reorder_q, skb);
748 }
749 } else {
750 /* No sequence numbers. Add the skb to the tail of the
751 * reorder queue. This ensures that it will be
752 * delivered after all previous sequenced skbs.
753 */
754 skb_queue_tail(&session->reorder_q, skb);
755 }
756
757 /* Try to dequeue as many skbs from reorder_q as we can. */
758 pppol2tp_recv_dequeue(session);
759
760 return 0;
761
762 discard:
763 session->stats.rx_errors++;
764 kfree_skb(skb);
765 sock_put(session->sock);
766 sock_put(sock);
767
768 return 0;
769
770 discard_bad_csum:
771 LIMIT_NETDEBUG("%s: UDP: bad checksum\n", tunnel->name);
772 UDP_INC_STATS_USER(&init_net, UDP_MIB_INERRORS, 0);
773 tunnel->stats.rx_errors++;
774 kfree_skb(skb);
775
776 return 0;
777
778 error:
779 /* Put UDP header back */
780 __skb_push(skb, sizeof(struct udphdr));
781 sock_put(sock);
782
783 no_tunnel:
784 return 1;
785 }
786
787 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
788 * Return codes:
789 * 0 : success.
790 * <0: error
791 * >0: skb should be passed up to userspace as UDP.
792 */
793 static int pppol2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
794 {
795 struct pppol2tp_tunnel *tunnel;
796
797 tunnel = pppol2tp_sock_to_tunnel(sk);
798 if (tunnel == NULL)
799 goto pass_up;
800
801 PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
802 "%s: received %d bytes\n", tunnel->name, skb->len);
803
804 if (pppol2tp_recv_core(sk, skb))
805 goto pass_up_put;
806
807 sock_put(sk);
808 return 0;
809
810 pass_up_put:
811 sock_put(sk);
812 pass_up:
813 return 1;
814 }
815
816 /* Receive message. This is the recvmsg for the PPPoL2TP socket.
817 */
818 static int pppol2tp_recvmsg(struct kiocb *iocb, struct socket *sock,
819 struct msghdr *msg, size_t len,
820 int flags)
821 {
822 int err;
823 struct sk_buff *skb;
824 struct sock *sk = sock->sk;
825
826 err = -EIO;
827 if (sk->sk_state & PPPOX_BOUND)
828 goto end;
829
830 msg->msg_namelen = 0;
831
832 err = 0;
833 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
834 flags & MSG_DONTWAIT, &err);
835 if (!skb)
836 goto end;
837
838 if (len > skb->len)
839 len = skb->len;
840 else if (len < skb->len)
841 msg->msg_flags |= MSG_TRUNC;
842
843 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
844 if (likely(err == 0))
845 err = len;
846
847 kfree_skb(skb);
848 end:
849 return err;
850 }
851
852 /************************************************************************
853 * Transmit handling
854 ***********************************************************************/
855
856 /* Tell how big L2TP headers are for a particular session. This
857 * depends on whether sequence numbers are being used.
858 */
859 static inline int pppol2tp_l2tp_header_len(struct pppol2tp_session *session)
860 {
861 if (session->send_seq)
862 return PPPOL2TP_L2TP_HDR_SIZE_SEQ;
863
864 return PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
865 }
866
867 /* Build an L2TP header for the session into the buffer provided.
868 */
869 static void pppol2tp_build_l2tp_header(struct pppol2tp_session *session,
870 void *buf)
871 {
872 __be16 *bufp = buf;
873 u16 flags = L2TP_HDR_VER;
874
875 if (session->send_seq)
876 flags |= L2TP_HDRFLAG_S;
877
878 /* Setup L2TP header.
879 * FIXME: Can this ever be unaligned? Is direct dereferencing of
880 * 16-bit header fields safe here for all architectures?
881 */
882 *bufp++ = htons(flags);
883 *bufp++ = htons(session->tunnel_addr.d_tunnel);
884 *bufp++ = htons(session->tunnel_addr.d_session);
885 if (session->send_seq) {
886 *bufp++ = htons(session->ns);
887 *bufp++ = 0;
888 session->ns++;
889 PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
890 "%s: updated ns to %hu\n", session->name, session->ns);
891 }
892 }
893
894 /* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
895 * when a user application does a sendmsg() on the session socket. L2TP and
896 * PPP headers must be inserted into the user's data.
897 */
898 static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
899 size_t total_len)
900 {
901 static const unsigned char ppph[2] = { 0xff, 0x03 };
902 struct sock *sk = sock->sk;
903 struct inet_sock *inet;
904 __wsum csum;
905 struct sk_buff *skb;
906 int error;
907 int hdr_len;
908 struct pppol2tp_session *session;
909 struct pppol2tp_tunnel *tunnel;
910 struct udphdr *uh;
911 unsigned int len;
912 struct sock *sk_tun;
913 u16 udp_len;
914
915 error = -ENOTCONN;
916 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
917 goto error;
918
919 /* Get session and tunnel contexts */
920 error = -EBADF;
921 session = pppol2tp_sock_to_session(sk);
922 if (session == NULL)
923 goto error;
924
925 sk_tun = session->tunnel_sock;
926 tunnel = pppol2tp_sock_to_tunnel(sk_tun);
927 if (tunnel == NULL)
928 goto error_put_sess;
929
930 /* What header length is configured for this session? */
931 hdr_len = pppol2tp_l2tp_header_len(session);
932
933 /* Allocate a socket buffer */
934 error = -ENOMEM;
935 skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) +
936 sizeof(struct udphdr) + hdr_len +
937 sizeof(ppph) + total_len,
938 0, GFP_KERNEL);
939 if (!skb)
940 goto error_put_sess_tun;
941
942 /* Reserve space for headers. */
943 skb_reserve(skb, NET_SKB_PAD);
944 skb_reset_network_header(skb);
945 skb_reserve(skb, sizeof(struct iphdr));
946 skb_reset_transport_header(skb);
947
948 /* Build UDP header */
949 inet = inet_sk(sk_tun);
950 udp_len = hdr_len + sizeof(ppph) + total_len;
951 uh = (struct udphdr *) skb->data;
952 uh->source = inet->sport;
953 uh->dest = inet->dport;
954 uh->len = htons(udp_len);
955 uh->check = 0;
956 skb_put(skb, sizeof(struct udphdr));
957
958 /* Build L2TP header */
959 pppol2tp_build_l2tp_header(session, skb->data);
960 skb_put(skb, hdr_len);
961
962 /* Add PPP header */
963 skb->data[0] = ppph[0];
964 skb->data[1] = ppph[1];
965 skb_put(skb, 2);
966
967 /* Copy user data into skb */
968 error = memcpy_fromiovec(skb->data, m->msg_iov, total_len);
969 if (error < 0) {
970 kfree_skb(skb);
971 goto error_put_sess_tun;
972 }
973 skb_put(skb, total_len);
974
975 /* Calculate UDP checksum if configured to do so */
976 if (sk_tun->sk_no_check == UDP_CSUM_NOXMIT)
977 skb->ip_summed = CHECKSUM_NONE;
978 else if (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM)) {
979 skb->ip_summed = CHECKSUM_COMPLETE;
980 csum = skb_checksum(skb, 0, udp_len, 0);
981 uh->check = csum_tcpudp_magic(inet->saddr, inet->daddr,
982 udp_len, IPPROTO_UDP, csum);
983 if (uh->check == 0)
984 uh->check = CSUM_MANGLED_0;
985 } else {
986 skb->ip_summed = CHECKSUM_PARTIAL;
987 skb->csum_start = skb_transport_header(skb) - skb->head;
988 skb->csum_offset = offsetof(struct udphdr, check);
989 uh->check = ~csum_tcpudp_magic(inet->saddr, inet->daddr,
990 udp_len, IPPROTO_UDP, 0);
991 }
992
993 /* Debug */
994 if (session->send_seq)
995 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
996 "%s: send %Zd bytes, ns=%hu\n", session->name,
997 total_len, session->ns - 1);
998 else
999 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
1000 "%s: send %Zd bytes\n", session->name, total_len);
1001
1002 if (session->debug & PPPOL2TP_MSG_DATA) {
1003 int i;
1004 unsigned char *datap = skb->data;
1005
1006 printk(KERN_DEBUG "%s: xmit:", session->name);
1007 for (i = 0; i < total_len; i++) {
1008 printk(" %02X", *datap++);
1009 if (i == 15) {
1010 printk(" ...");
1011 break;
1012 }
1013 }
1014 printk("\n");
1015 }
1016
1017 /* Queue the packet to IP for output */
1018 len = skb->len;
1019 error = ip_queue_xmit(skb, 1);
1020
1021 /* Update stats */
1022 if (error >= 0) {
1023 tunnel->stats.tx_packets++;
1024 tunnel->stats.tx_bytes += len;
1025 session->stats.tx_packets++;
1026 session->stats.tx_bytes += len;
1027 } else {
1028 tunnel->stats.tx_errors++;
1029 session->stats.tx_errors++;
1030 }
1031
1032 return error;
1033
1034 error_put_sess_tun:
1035 sock_put(session->tunnel_sock);
1036 error_put_sess:
1037 sock_put(sk);
1038 error:
1039 return error;
1040 }
1041
1042 /* Automatically called when the skb is freed.
1043 */
1044 static void pppol2tp_sock_wfree(struct sk_buff *skb)
1045 {
1046 sock_put(skb->sk);
1047 }
1048
1049 /* For data skbs that we transmit, we associate with the tunnel socket
1050 * but don't do accounting.
1051 */
1052 static inline void pppol2tp_skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1053 {
1054 sock_hold(sk);
1055 skb->sk = sk;
1056 skb->destructor = pppol2tp_sock_wfree;
1057 }
1058
1059 /* Transmit function called by generic PPP driver. Sends PPP frame
1060 * over PPPoL2TP socket.
1061 *
1062 * This is almost the same as pppol2tp_sendmsg(), but rather than
1063 * being called with a msghdr from userspace, it is called with a skb
1064 * from the kernel.
1065 *
1066 * The supplied skb from ppp doesn't have enough headroom for the
1067 * insertion of L2TP, UDP and IP headers so we need to allocate more
1068 * headroom in the skb. This will create a cloned skb. But we must be
1069 * careful in the error case because the caller will expect to free
1070 * the skb it supplied, not our cloned skb. So we take care to always
1071 * leave the original skb unfreed if we return an error.
1072 */
1073 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
1074 {
1075 static const u8 ppph[2] = { 0xff, 0x03 };
1076 struct sock *sk = (struct sock *) chan->private;
1077 struct sock *sk_tun;
1078 int hdr_len;
1079 u16 udp_len;
1080 struct pppol2tp_session *session;
1081 struct pppol2tp_tunnel *tunnel;
1082 int rc;
1083 int headroom;
1084 int data_len = skb->len;
1085 struct inet_sock *inet;
1086 __wsum csum;
1087 struct udphdr *uh;
1088 unsigned int len;
1089 int old_headroom;
1090 int new_headroom;
1091
1092 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
1093 goto abort;
1094
1095 /* Get session and tunnel contexts from the socket */
1096 session = pppol2tp_sock_to_session(sk);
1097 if (session == NULL)
1098 goto abort;
1099
1100 sk_tun = session->tunnel_sock;
1101 if (sk_tun == NULL)
1102 goto abort_put_sess;
1103 tunnel = pppol2tp_sock_to_tunnel(sk_tun);
1104 if (tunnel == NULL)
1105 goto abort_put_sess;
1106
1107 /* What header length is configured for this session? */
1108 hdr_len = pppol2tp_l2tp_header_len(session);
1109
1110 /* Check that there's enough headroom in the skb to insert IP,
1111 * UDP and L2TP and PPP headers. If not enough, expand it to
1112 * make room. Adjust truesize.
1113 */
1114 headroom = NET_SKB_PAD + sizeof(struct iphdr) +
1115 sizeof(struct udphdr) + hdr_len + sizeof(ppph);
1116 old_headroom = skb_headroom(skb);
1117 if (skb_cow_head(skb, headroom))
1118 goto abort_put_sess_tun;
1119
1120 new_headroom = skb_headroom(skb);
1121 skb_orphan(skb);
1122 skb->truesize += new_headroom - old_headroom;
1123
1124 /* Setup PPP header */
1125 __skb_push(skb, sizeof(ppph));
1126 skb->data[0] = ppph[0];
1127 skb->data[1] = ppph[1];
1128
1129 /* Setup L2TP header */
1130 pppol2tp_build_l2tp_header(session, __skb_push(skb, hdr_len));
1131
1132 udp_len = sizeof(struct udphdr) + hdr_len + sizeof(ppph) + data_len;
1133
1134 /* Setup UDP header */
1135 inet = inet_sk(sk_tun);
1136 __skb_push(skb, sizeof(*uh));
1137 skb_reset_transport_header(skb);
1138 uh = udp_hdr(skb);
1139 uh->source = inet->sport;
1140 uh->dest = inet->dport;
1141 uh->len = htons(udp_len);
1142 uh->check = 0;
1143
1144 /* Debug */
1145 if (session->send_seq)
1146 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
1147 "%s: send %d bytes, ns=%hu\n", session->name,
1148 data_len, session->ns - 1);
1149 else
1150 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
1151 "%s: send %d bytes\n", session->name, data_len);
1152
1153 if (session->debug & PPPOL2TP_MSG_DATA) {
1154 int i;
1155 unsigned char *datap = skb->data;
1156
1157 printk(KERN_DEBUG "%s: xmit:", session->name);
1158 for (i = 0; i < data_len; i++) {
1159 printk(" %02X", *datap++);
1160 if (i == 31) {
1161 printk(" ...");
1162 break;
1163 }
1164 }
1165 printk("\n");
1166 }
1167
1168 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1169 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
1170 IPSKB_REROUTED);
1171 nf_reset(skb);
1172
1173 /* Get routing info from the tunnel socket */
1174 skb_dst_drop(skb);
1175 skb_dst_set(skb, dst_clone(__sk_dst_get(sk_tun)));
1176 pppol2tp_skb_set_owner_w(skb, sk_tun);
1177
1178 /* Calculate UDP checksum if configured to do so */
1179 if (sk_tun->sk_no_check == UDP_CSUM_NOXMIT)
1180 skb->ip_summed = CHECKSUM_NONE;
1181 else if ((skb_dst(skb) && skb_dst(skb)->dev) &&
1182 (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) {
1183 skb->ip_summed = CHECKSUM_COMPLETE;
1184 csum = skb_checksum(skb, 0, udp_len, 0);
1185 uh->check = csum_tcpudp_magic(inet->saddr, inet->daddr,
1186 udp_len, IPPROTO_UDP, csum);
1187 if (uh->check == 0)
1188 uh->check = CSUM_MANGLED_0;
1189 } else {
1190 skb->ip_summed = CHECKSUM_PARTIAL;
1191 skb->csum_start = skb_transport_header(skb) - skb->head;
1192 skb->csum_offset = offsetof(struct udphdr, check);
1193 uh->check = ~csum_tcpudp_magic(inet->saddr, inet->daddr,
1194 udp_len, IPPROTO_UDP, 0);
1195 }
1196
1197 /* Queue the packet to IP for output */
1198 len = skb->len;
1199 rc = ip_queue_xmit(skb, 1);
1200
1201 /* Update stats */
1202 if (rc >= 0) {
1203 tunnel->stats.tx_packets++;
1204 tunnel->stats.tx_bytes += len;
1205 session->stats.tx_packets++;
1206 session->stats.tx_bytes += len;
1207 } else {
1208 tunnel->stats.tx_errors++;
1209 session->stats.tx_errors++;
1210 }
1211
1212 sock_put(sk_tun);
1213 sock_put(sk);
1214 return 1;
1215
1216 abort_put_sess_tun:
1217 sock_put(sk_tun);
1218 abort_put_sess:
1219 sock_put(sk);
1220 abort:
1221 /* Free the original skb */
1222 kfree_skb(skb);
1223 return 1;
1224 }
1225
1226 /*****************************************************************************
1227 * Session (and tunnel control) socket create/destroy.
1228 *****************************************************************************/
1229
1230 /* When the tunnel UDP socket is closed, all the attached sockets need to go
1231 * too.
1232 */
1233 static void pppol2tp_tunnel_closeall(struct pppol2tp_tunnel *tunnel)
1234 {
1235 int hash;
1236 struct hlist_node *walk;
1237 struct hlist_node *tmp;
1238 struct pppol2tp_session *session;
1239 struct sock *sk;
1240
1241 BUG_ON(tunnel == NULL);
1242
1243 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1244 "%s: closing all sessions...\n", tunnel->name);
1245
1246 write_lock_bh(&tunnel->hlist_lock);
1247 for (hash = 0; hash < PPPOL2TP_HASH_SIZE; hash++) {
1248 again:
1249 hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
1250 struct sk_buff *skb;
1251
1252 session = hlist_entry(walk, struct pppol2tp_session, hlist);
1253
1254 sk = session->sock;
1255
1256 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1257 "%s: closing session\n", session->name);
1258
1259 hlist_del_init(&session->hlist);
1260
1261 /* Since we should hold the sock lock while
1262 * doing any unbinding, we need to release the
1263 * lock we're holding before taking that lock.
1264 * Hold a reference to the sock so it doesn't
1265 * disappear as we're jumping between locks.
1266 */
1267 sock_hold(sk);
1268 write_unlock_bh(&tunnel->hlist_lock);
1269 lock_sock(sk);
1270
1271 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
1272 pppox_unbind_sock(sk);
1273 sk->sk_state = PPPOX_DEAD;
1274 sk->sk_state_change(sk);
1275 }
1276
1277 /* Purge any queued data */
1278 skb_queue_purge(&sk->sk_receive_queue);
1279 skb_queue_purge(&sk->sk_write_queue);
1280 while ((skb = skb_dequeue(&session->reorder_q))) {
1281 kfree_skb(skb);
1282 sock_put(sk);
1283 }
1284
1285 release_sock(sk);
1286 sock_put(sk);
1287
1288 /* Now restart from the beginning of this hash
1289 * chain. We always remove a session from the
1290 * list so we are guaranteed to make forward
1291 * progress.
1292 */
1293 write_lock_bh(&tunnel->hlist_lock);
1294 goto again;
1295 }
1296 }
1297 write_unlock_bh(&tunnel->hlist_lock);
1298 }
1299
1300 /* Really kill the tunnel.
1301 * Come here only when all sessions have been cleared from the tunnel.
1302 */
1303 static void pppol2tp_tunnel_free(struct pppol2tp_tunnel *tunnel)
1304 {
1305 struct pppol2tp_net *pn = pppol2tp_pernet(tunnel->pppol2tp_net);
1306
1307 /* Remove from socket list */
1308 write_lock_bh(&pn->pppol2tp_tunnel_list_lock);
1309 list_del_init(&tunnel->list);
1310 write_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
1311
1312 atomic_dec(&pppol2tp_tunnel_count);
1313 kfree(tunnel);
1314 }
1315
1316 /* Tunnel UDP socket destruct hook.
1317 * The tunnel context is deleted only when all session sockets have been
1318 * closed.
1319 */
1320 static void pppol2tp_tunnel_destruct(struct sock *sk)
1321 {
1322 struct pppol2tp_tunnel *tunnel;
1323
1324 tunnel = sk->sk_user_data;
1325 if (tunnel == NULL)
1326 goto end;
1327
1328 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1329 "%s: closing...\n", tunnel->name);
1330
1331 /* Close all sessions */
1332 pppol2tp_tunnel_closeall(tunnel);
1333
1334 /* No longer an encapsulation socket. See net/ipv4/udp.c */
1335 (udp_sk(sk))->encap_type = 0;
1336 (udp_sk(sk))->encap_rcv = NULL;
1337
1338 /* Remove hooks into tunnel socket */
1339 tunnel->sock = NULL;
1340 sk->sk_destruct = tunnel->old_sk_destruct;
1341 sk->sk_user_data = NULL;
1342
1343 /* Call original (UDP) socket descructor */
1344 if (sk->sk_destruct != NULL)
1345 (*sk->sk_destruct)(sk);
1346
1347 pppol2tp_tunnel_dec_refcount(tunnel);
1348
1349 end:
1350 return;
1351 }
1352
1353 /* Really kill the session socket. (Called from sock_put() if
1354 * refcnt == 0.)
1355 */
1356 static void pppol2tp_session_destruct(struct sock *sk)
1357 {
1358 struct pppol2tp_session *session = NULL;
1359
1360 if (sk->sk_user_data != NULL) {
1361 struct pppol2tp_tunnel *tunnel;
1362
1363 session = sk->sk_user_data;
1364 if (session == NULL)
1365 goto out;
1366
1367 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
1368
1369 /* Don't use pppol2tp_sock_to_tunnel() here to
1370 * get the tunnel context because the tunnel
1371 * socket might have already been closed (its
1372 * sk->sk_user_data will be NULL) so use the
1373 * session's private tunnel ptr instead.
1374 */
1375 tunnel = session->tunnel;
1376 if (tunnel != NULL) {
1377 BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
1378
1379 /* If session_id is zero, this is a null
1380 * session context, which was created for a
1381 * socket that is being used only to manage
1382 * tunnels.
1383 */
1384 if (session->tunnel_addr.s_session != 0) {
1385 /* Delete the session socket from the
1386 * hash
1387 */
1388 write_lock_bh(&tunnel->hlist_lock);
1389 hlist_del_init(&session->hlist);
1390 write_unlock_bh(&tunnel->hlist_lock);
1391
1392 atomic_dec(&pppol2tp_session_count);
1393 }
1394
1395 /* This will delete the tunnel context if this
1396 * is the last session on the tunnel.
1397 */
1398 session->tunnel = NULL;
1399 session->tunnel_sock = NULL;
1400 pppol2tp_tunnel_dec_refcount(tunnel);
1401 }
1402 }
1403
1404 kfree(session);
1405 out:
1406 return;
1407 }
1408
1409 /* Called when the PPPoX socket (session) is closed.
1410 */
1411 static int pppol2tp_release(struct socket *sock)
1412 {
1413 struct sock *sk = sock->sk;
1414 struct pppol2tp_session *session;
1415 int error;
1416
1417 if (!sk)
1418 return 0;
1419
1420 error = -EBADF;
1421 lock_sock(sk);
1422 if (sock_flag(sk, SOCK_DEAD) != 0)
1423 goto error;
1424
1425 pppox_unbind_sock(sk);
1426
1427 /* Signal the death of the socket. */
1428 sk->sk_state = PPPOX_DEAD;
1429 sock_orphan(sk);
1430 sock->sk = NULL;
1431
1432 session = pppol2tp_sock_to_session(sk);
1433
1434 /* Purge any queued data */
1435 skb_queue_purge(&sk->sk_receive_queue);
1436 skb_queue_purge(&sk->sk_write_queue);
1437 if (session != NULL) {
1438 struct sk_buff *skb;
1439 while ((skb = skb_dequeue(&session->reorder_q))) {
1440 kfree_skb(skb);
1441 sock_put(sk);
1442 }
1443 sock_put(sk);
1444 }
1445
1446 release_sock(sk);
1447
1448 /* This will delete the session context via
1449 * pppol2tp_session_destruct() if the socket's refcnt drops to
1450 * zero.
1451 */
1452 sock_put(sk);
1453
1454 return 0;
1455
1456 error:
1457 release_sock(sk);
1458 return error;
1459 }
1460
1461 /* Internal function to prepare a tunnel (UDP) socket to have PPPoX
1462 * sockets attached to it.
1463 */
1464 static struct sock *pppol2tp_prepare_tunnel_socket(struct net *net,
1465 int fd, u16 tunnel_id, int *error)
1466 {
1467 int err;
1468 struct socket *sock = NULL;
1469 struct sock *sk;
1470 struct pppol2tp_tunnel *tunnel;
1471 struct pppol2tp_net *pn;
1472 struct sock *ret = NULL;
1473
1474 /* Get the tunnel UDP socket from the fd, which was opened by
1475 * the userspace L2TP daemon.
1476 */
1477 err = -EBADF;
1478 sock = sockfd_lookup(fd, &err);
1479 if (!sock) {
1480 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR,
1481 "tunl %hu: sockfd_lookup(fd=%d) returned %d\n",
1482 tunnel_id, fd, err);
1483 goto err;
1484 }
1485
1486 sk = sock->sk;
1487
1488 /* Quick sanity checks */
1489 err = -EPROTONOSUPPORT;
1490 if (sk->sk_protocol != IPPROTO_UDP) {
1491 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR,
1492 "tunl %hu: fd %d wrong protocol, got %d, expected %d\n",
1493 tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP);
1494 goto err;
1495 }
1496 err = -EAFNOSUPPORT;
1497 if (sock->ops->family != AF_INET) {
1498 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR,
1499 "tunl %hu: fd %d wrong family, got %d, expected %d\n",
1500 tunnel_id, fd, sock->ops->family, AF_INET);
1501 goto err;
1502 }
1503
1504 err = -ENOTCONN;
1505
1506 /* Check if this socket has already been prepped */
1507 tunnel = (struct pppol2tp_tunnel *)sk->sk_user_data;
1508 if (tunnel != NULL) {
1509 /* User-data field already set */
1510 err = -EBUSY;
1511 BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
1512
1513 /* This socket has already been prepped */
1514 ret = tunnel->sock;
1515 goto out;
1516 }
1517
1518 /* This socket is available and needs prepping. Create a new tunnel
1519 * context and init it.
1520 */
1521 sk->sk_user_data = tunnel = kzalloc(sizeof(struct pppol2tp_tunnel), GFP_KERNEL);
1522 if (sk->sk_user_data == NULL) {
1523 err = -ENOMEM;
1524 goto err;
1525 }
1526
1527 tunnel->magic = L2TP_TUNNEL_MAGIC;
1528 sprintf(&tunnel->name[0], "tunl %hu", tunnel_id);
1529
1530 tunnel->stats.tunnel_id = tunnel_id;
1531 tunnel->debug = PPPOL2TP_DEFAULT_DEBUG_FLAGS;
1532
1533 /* Hook on the tunnel socket destructor so that we can cleanup
1534 * if the tunnel socket goes away.
1535 */
1536 tunnel->old_sk_destruct = sk->sk_destruct;
1537 sk->sk_destruct = &pppol2tp_tunnel_destruct;
1538
1539 tunnel->sock = sk;
1540 sk->sk_allocation = GFP_ATOMIC;
1541
1542 /* Misc init */
1543 rwlock_init(&tunnel->hlist_lock);
1544
1545 /* The net we belong to */
1546 tunnel->pppol2tp_net = net;
1547 pn = pppol2tp_pernet(net);
1548
1549 /* Add tunnel to our list */
1550 INIT_LIST_HEAD(&tunnel->list);
1551 write_lock_bh(&pn->pppol2tp_tunnel_list_lock);
1552 list_add(&tunnel->list, &pn->pppol2tp_tunnel_list);
1553 write_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
1554 atomic_inc(&pppol2tp_tunnel_count);
1555
1556 /* Bump the reference count. The tunnel context is deleted
1557 * only when this drops to zero.
1558 */
1559 pppol2tp_tunnel_inc_refcount(tunnel);
1560
1561 /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */
1562 (udp_sk(sk))->encap_type = UDP_ENCAP_L2TPINUDP;
1563 (udp_sk(sk))->encap_rcv = pppol2tp_udp_encap_recv;
1564
1565 ret = tunnel->sock;
1566
1567 *error = 0;
1568 out:
1569 if (sock)
1570 sockfd_put(sock);
1571
1572 return ret;
1573
1574 err:
1575 *error = err;
1576 goto out;
1577 }
1578
1579 static struct proto pppol2tp_sk_proto = {
1580 .name = "PPPOL2TP",
1581 .owner = THIS_MODULE,
1582 .obj_size = sizeof(struct pppox_sock),
1583 };
1584
1585 /* socket() handler. Initialize a new struct sock.
1586 */
1587 static int pppol2tp_create(struct net *net, struct socket *sock)
1588 {
1589 int error = -ENOMEM;
1590 struct sock *sk;
1591
1592 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto);
1593 if (!sk)
1594 goto out;
1595
1596 sock_init_data(sock, sk);
1597
1598 sock->state = SS_UNCONNECTED;
1599 sock->ops = &pppol2tp_ops;
1600
1601 sk->sk_backlog_rcv = pppol2tp_recv_core;
1602 sk->sk_protocol = PX_PROTO_OL2TP;
1603 sk->sk_family = PF_PPPOX;
1604 sk->sk_state = PPPOX_NONE;
1605 sk->sk_type = SOCK_STREAM;
1606 sk->sk_destruct = pppol2tp_session_destruct;
1607
1608 error = 0;
1609
1610 out:
1611 return error;
1612 }
1613
1614 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
1615 */
1616 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
1617 int sockaddr_len, int flags)
1618 {
1619 struct sock *sk = sock->sk;
1620 struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
1621 struct pppox_sock *po = pppox_sk(sk);
1622 struct sock *tunnel_sock = NULL;
1623 struct pppol2tp_session *session = NULL;
1624 struct pppol2tp_tunnel *tunnel;
1625 struct dst_entry *dst;
1626 int error = 0;
1627
1628 lock_sock(sk);
1629
1630 error = -EINVAL;
1631 if (sp->sa_protocol != PX_PROTO_OL2TP)
1632 goto end;
1633
1634 /* Check for already bound sockets */
1635 error = -EBUSY;
1636 if (sk->sk_state & PPPOX_CONNECTED)
1637 goto end;
1638
1639 /* We don't supporting rebinding anyway */
1640 error = -EALREADY;
1641 if (sk->sk_user_data)
1642 goto end; /* socket is already attached */
1643
1644 /* Don't bind if s_tunnel is 0 */
1645 error = -EINVAL;
1646 if (sp->pppol2tp.s_tunnel == 0)
1647 goto end;
1648
1649 /* Special case: prepare tunnel socket if s_session and
1650 * d_session is 0. Otherwise look up tunnel using supplied
1651 * tunnel id.
1652 */
1653 if ((sp->pppol2tp.s_session == 0) && (sp->pppol2tp.d_session == 0)) {
1654 tunnel_sock = pppol2tp_prepare_tunnel_socket(sock_net(sk),
1655 sp->pppol2tp.fd,
1656 sp->pppol2tp.s_tunnel,
1657 &error);
1658 if (tunnel_sock == NULL)
1659 goto end;
1660
1661 tunnel = tunnel_sock->sk_user_data;
1662 } else {
1663 tunnel = pppol2tp_tunnel_find(sock_net(sk), sp->pppol2tp.s_tunnel);
1664
1665 /* Error if we can't find the tunnel */
1666 error = -ENOENT;
1667 if (tunnel == NULL)
1668 goto end;
1669
1670 tunnel_sock = tunnel->sock;
1671 }
1672
1673 /* Check that this session doesn't already exist */
1674 error = -EEXIST;
1675 session = pppol2tp_session_find(tunnel, sp->pppol2tp.s_session);
1676 if (session != NULL)
1677 goto end;
1678
1679 /* Allocate and initialize a new session context. */
1680 session = kzalloc(sizeof(struct pppol2tp_session), GFP_KERNEL);
1681 if (session == NULL) {
1682 error = -ENOMEM;
1683 goto end;
1684 }
1685
1686 skb_queue_head_init(&session->reorder_q);
1687
1688 session->magic = L2TP_SESSION_MAGIC;
1689 session->owner = current->pid;
1690 session->sock = sk;
1691 session->tunnel = tunnel;
1692 session->tunnel_sock = tunnel_sock;
1693 session->tunnel_addr = sp->pppol2tp;
1694 sprintf(&session->name[0], "sess %hu/%hu",
1695 session->tunnel_addr.s_tunnel,
1696 session->tunnel_addr.s_session);
1697
1698 session->stats.tunnel_id = session->tunnel_addr.s_tunnel;
1699 session->stats.session_id = session->tunnel_addr.s_session;
1700
1701 INIT_HLIST_NODE(&session->hlist);
1702
1703 /* Inherit debug options from tunnel */
1704 session->debug = tunnel->debug;
1705
1706 /* Default MTU must allow space for UDP/L2TP/PPP
1707 * headers.
1708 */
1709 session->mtu = session->mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
1710
1711 /* If PMTU discovery was enabled, use the MTU that was discovered */
1712 dst = sk_dst_get(sk);
1713 if (dst != NULL) {
1714 u32 pmtu = dst_mtu(__sk_dst_get(sk));
1715 if (pmtu != 0)
1716 session->mtu = session->mru = pmtu -
1717 PPPOL2TP_HEADER_OVERHEAD;
1718 dst_release(dst);
1719 }
1720
1721 /* Special case: if source & dest session_id == 0x0000, this socket is
1722 * being created to manage the tunnel. Don't add the session to the
1723 * session hash list, just set up the internal context for use by
1724 * ioctl() and sockopt() handlers.
1725 */
1726 if ((session->tunnel_addr.s_session == 0) &&
1727 (session->tunnel_addr.d_session == 0)) {
1728 error = 0;
1729 sk->sk_user_data = session;
1730 goto out_no_ppp;
1731 }
1732
1733 /* Get tunnel context from the tunnel socket */
1734 tunnel = pppol2tp_sock_to_tunnel(tunnel_sock);
1735 if (tunnel == NULL) {
1736 error = -EBADF;
1737 goto end;
1738 }
1739
1740 /* Right now, because we don't have a way to push the incoming skb's
1741 * straight through the UDP layer, the only header we need to worry
1742 * about is the L2TP header. This size is different depending on
1743 * whether sequence numbers are enabled for the data channel.
1744 */
1745 po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
1746
1747 po->chan.private = sk;
1748 po->chan.ops = &pppol2tp_chan_ops;
1749 po->chan.mtu = session->mtu;
1750
1751 error = ppp_register_net_channel(sock_net(sk), &po->chan);
1752 if (error)
1753 goto end_put_tun;
1754
1755 /* This is how we get the session context from the socket. */
1756 sk->sk_user_data = session;
1757
1758 /* Add session to the tunnel's hash list */
1759 write_lock_bh(&tunnel->hlist_lock);
1760 hlist_add_head(&session->hlist,
1761 pppol2tp_session_id_hash(tunnel,
1762 session->tunnel_addr.s_session));
1763 write_unlock_bh(&tunnel->hlist_lock);
1764
1765 atomic_inc(&pppol2tp_session_count);
1766
1767 out_no_ppp:
1768 pppol2tp_tunnel_inc_refcount(tunnel);
1769 sk->sk_state = PPPOX_CONNECTED;
1770 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1771 "%s: created\n", session->name);
1772
1773 end_put_tun:
1774 sock_put(tunnel_sock);
1775 end:
1776 release_sock(sk);
1777
1778 if (error != 0) {
1779 if (session)
1780 PRINTK(session->debug,
1781 PPPOL2TP_MSG_CONTROL, KERN_WARNING,
1782 "%s: connect failed: %d\n",
1783 session->name, error);
1784 else
1785 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_WARNING,
1786 "connect failed: %d\n", error);
1787 }
1788
1789 return error;
1790 }
1791
1792 /* getname() support.
1793 */
1794 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
1795 int *usockaddr_len, int peer)
1796 {
1797 int len = sizeof(struct sockaddr_pppol2tp);
1798 struct sockaddr_pppol2tp sp;
1799 int error = 0;
1800 struct pppol2tp_session *session;
1801
1802 error = -ENOTCONN;
1803 if (sock->sk->sk_state != PPPOX_CONNECTED)
1804 goto end;
1805
1806 session = pppol2tp_sock_to_session(sock->sk);
1807 if (session == NULL) {
1808 error = -EBADF;
1809 goto end;
1810 }
1811
1812 sp.sa_family = AF_PPPOX;
1813 sp.sa_protocol = PX_PROTO_OL2TP;
1814 memcpy(&sp.pppol2tp, &session->tunnel_addr,
1815 sizeof(struct pppol2tp_addr));
1816
1817 memcpy(uaddr, &sp, len);
1818
1819 *usockaddr_len = len;
1820
1821 error = 0;
1822 sock_put(sock->sk);
1823
1824 end:
1825 return error;
1826 }
1827
1828 /****************************************************************************
1829 * ioctl() handlers.
1830 *
1831 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1832 * sockets. However, in order to control kernel tunnel features, we allow
1833 * userspace to create a special "tunnel" PPPoX socket which is used for
1834 * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
1835 * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
1836 * calls.
1837 ****************************************************************************/
1838
1839 /* Session ioctl helper.
1840 */
1841 static int pppol2tp_session_ioctl(struct pppol2tp_session *session,
1842 unsigned int cmd, unsigned long arg)
1843 {
1844 struct ifreq ifr;
1845 int err = 0;
1846 struct sock *sk = session->sock;
1847 int val = (int) arg;
1848
1849 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1850 "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n",
1851 session->name, cmd, arg);
1852
1853 sock_hold(sk);
1854
1855 switch (cmd) {
1856 case SIOCGIFMTU:
1857 err = -ENXIO;
1858 if (!(sk->sk_state & PPPOX_CONNECTED))
1859 break;
1860
1861 err = -EFAULT;
1862 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1863 break;
1864 ifr.ifr_mtu = session->mtu;
1865 if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq)))
1866 break;
1867
1868 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1869 "%s: get mtu=%d\n", session->name, session->mtu);
1870 err = 0;
1871 break;
1872
1873 case SIOCSIFMTU:
1874 err = -ENXIO;
1875 if (!(sk->sk_state & PPPOX_CONNECTED))
1876 break;
1877
1878 err = -EFAULT;
1879 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1880 break;
1881
1882 session->mtu = ifr.ifr_mtu;
1883
1884 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1885 "%s: set mtu=%d\n", session->name, session->mtu);
1886 err = 0;
1887 break;
1888
1889 case PPPIOCGMRU:
1890 err = -ENXIO;
1891 if (!(sk->sk_state & PPPOX_CONNECTED))
1892 break;
1893
1894 err = -EFAULT;
1895 if (put_user(session->mru, (int __user *) arg))
1896 break;
1897
1898 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1899 "%s: get mru=%d\n", session->name, session->mru);
1900 err = 0;
1901 break;
1902
1903 case PPPIOCSMRU:
1904 err = -ENXIO;
1905 if (!(sk->sk_state & PPPOX_CONNECTED))
1906 break;
1907
1908 err = -EFAULT;
1909 if (get_user(val,(int __user *) arg))
1910 break;
1911
1912 session->mru = val;
1913 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1914 "%s: set mru=%d\n", session->name, session->mru);
1915 err = 0;
1916 break;
1917
1918 case PPPIOCGFLAGS:
1919 err = -EFAULT;
1920 if (put_user(session->flags, (int __user *) arg))
1921 break;
1922
1923 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1924 "%s: get flags=%d\n", session->name, session->flags);
1925 err = 0;
1926 break;
1927
1928 case PPPIOCSFLAGS:
1929 err = -EFAULT;
1930 if (get_user(val, (int __user *) arg))
1931 break;
1932 session->flags = val;
1933 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1934 "%s: set flags=%d\n", session->name, session->flags);
1935 err = 0;
1936 break;
1937
1938 case PPPIOCGL2TPSTATS:
1939 err = -ENXIO;
1940 if (!(sk->sk_state & PPPOX_CONNECTED))
1941 break;
1942
1943 if (copy_to_user((void __user *) arg, &session->stats,
1944 sizeof(session->stats)))
1945 break;
1946 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1947 "%s: get L2TP stats\n", session->name);
1948 err = 0;
1949 break;
1950
1951 default:
1952 err = -ENOSYS;
1953 break;
1954 }
1955
1956 sock_put(sk);
1957
1958 return err;
1959 }
1960
1961 /* Tunnel ioctl helper.
1962 *
1963 * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data
1964 * specifies a session_id, the session ioctl handler is called. This allows an
1965 * application to retrieve session stats via a tunnel socket.
1966 */
1967 static int pppol2tp_tunnel_ioctl(struct pppol2tp_tunnel *tunnel,
1968 unsigned int cmd, unsigned long arg)
1969 {
1970 int err = 0;
1971 struct sock *sk = tunnel->sock;
1972 struct pppol2tp_ioc_stats stats_req;
1973
1974 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1975 "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n", tunnel->name,
1976 cmd, arg);
1977
1978 sock_hold(sk);
1979
1980 switch (cmd) {
1981 case PPPIOCGL2TPSTATS:
1982 err = -ENXIO;
1983 if (!(sk->sk_state & PPPOX_CONNECTED))
1984 break;
1985
1986 if (copy_from_user(&stats_req, (void __user *) arg,
1987 sizeof(stats_req))) {
1988 err = -EFAULT;
1989 break;
1990 }
1991 if (stats_req.session_id != 0) {
1992 /* resend to session ioctl handler */
1993 struct pppol2tp_session *session =
1994 pppol2tp_session_find(tunnel, stats_req.session_id);
1995 if (session != NULL)
1996 err = pppol2tp_session_ioctl(session, cmd, arg);
1997 else
1998 err = -EBADR;
1999 break;
2000 }
2001 #ifdef CONFIG_XFRM
2002 tunnel->stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0;
2003 #endif
2004 if (copy_to_user((void __user *) arg, &tunnel->stats,
2005 sizeof(tunnel->stats))) {
2006 err = -EFAULT;
2007 break;
2008 }
2009 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2010 "%s: get L2TP stats\n", tunnel->name);
2011 err = 0;
2012 break;
2013
2014 default:
2015 err = -ENOSYS;
2016 break;
2017 }
2018
2019 sock_put(sk);
2020
2021 return err;
2022 }
2023
2024 /* Main ioctl() handler.
2025 * Dispatch to tunnel or session helpers depending on the socket.
2026 */
2027 static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
2028 unsigned long arg)
2029 {
2030 struct sock *sk = sock->sk;
2031 struct pppol2tp_session *session;
2032 struct pppol2tp_tunnel *tunnel;
2033 int err;
2034
2035 if (!sk)
2036 return 0;
2037
2038 err = -EBADF;
2039 if (sock_flag(sk, SOCK_DEAD) != 0)
2040 goto end;
2041
2042 err = -ENOTCONN;
2043 if ((sk->sk_user_data == NULL) ||
2044 (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND))))
2045 goto end;
2046
2047 /* Get session context from the socket */
2048 err = -EBADF;
2049 session = pppol2tp_sock_to_session(sk);
2050 if (session == NULL)
2051 goto end;
2052
2053 /* Special case: if session's session_id is zero, treat ioctl as a
2054 * tunnel ioctl
2055 */
2056 if ((session->tunnel_addr.s_session == 0) &&
2057 (session->tunnel_addr.d_session == 0)) {
2058 err = -EBADF;
2059 tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock);
2060 if (tunnel == NULL)
2061 goto end_put_sess;
2062
2063 err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
2064 sock_put(session->tunnel_sock);
2065 goto end_put_sess;
2066 }
2067
2068 err = pppol2tp_session_ioctl(session, cmd, arg);
2069
2070 end_put_sess:
2071 sock_put(sk);
2072 end:
2073 return err;
2074 }
2075
2076 /*****************************************************************************
2077 * setsockopt() / getsockopt() support.
2078 *
2079 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
2080 * sockets. In order to control kernel tunnel features, we allow userspace to
2081 * create a special "tunnel" PPPoX socket which is used for control only.
2082 * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
2083 * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
2084 *****************************************************************************/
2085
2086 /* Tunnel setsockopt() helper.
2087 */
2088 static int pppol2tp_tunnel_setsockopt(struct sock *sk,
2089 struct pppol2tp_tunnel *tunnel,
2090 int optname, int val)
2091 {
2092 int err = 0;
2093
2094 switch (optname) {
2095 case PPPOL2TP_SO_DEBUG:
2096 tunnel->debug = val;
2097 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2098 "%s: set debug=%x\n", tunnel->name, tunnel->debug);
2099 break;
2100
2101 default:
2102 err = -ENOPROTOOPT;
2103 break;
2104 }
2105
2106 return err;
2107 }
2108
2109 /* Session setsockopt helper.
2110 */
2111 static int pppol2tp_session_setsockopt(struct sock *sk,
2112 struct pppol2tp_session *session,
2113 int optname, int val)
2114 {
2115 int err = 0;
2116
2117 switch (optname) {
2118 case PPPOL2TP_SO_RECVSEQ:
2119 if ((val != 0) && (val != 1)) {
2120 err = -EINVAL;
2121 break;
2122 }
2123 session->recv_seq = val ? -1 : 0;
2124 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2125 "%s: set recv_seq=%d\n", session->name,
2126 session->recv_seq);
2127 break;
2128
2129 case PPPOL2TP_SO_SENDSEQ:
2130 if ((val != 0) && (val != 1)) {
2131 err = -EINVAL;
2132 break;
2133 }
2134 session->send_seq = val ? -1 : 0;
2135 {
2136 struct sock *ssk = session->sock;
2137 struct pppox_sock *po = pppox_sk(ssk);
2138 po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
2139 PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
2140 }
2141 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2142 "%s: set send_seq=%d\n", session->name, session->send_seq);
2143 break;
2144
2145 case PPPOL2TP_SO_LNSMODE:
2146 if ((val != 0) && (val != 1)) {
2147 err = -EINVAL;
2148 break;
2149 }
2150 session->lns_mode = val ? -1 : 0;
2151 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2152 "%s: set lns_mode=%d\n", session->name,
2153 session->lns_mode);
2154 break;
2155
2156 case PPPOL2TP_SO_DEBUG:
2157 session->debug = val;
2158 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2159 "%s: set debug=%x\n", session->name, session->debug);
2160 break;
2161
2162 case PPPOL2TP_SO_REORDERTO:
2163 session->reorder_timeout = msecs_to_jiffies(val);
2164 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2165 "%s: set reorder_timeout=%d\n", session->name,
2166 session->reorder_timeout);
2167 break;
2168
2169 default:
2170 err = -ENOPROTOOPT;
2171 break;
2172 }
2173
2174 return err;
2175 }
2176
2177 /* Main setsockopt() entry point.
2178 * Does API checks, then calls either the tunnel or session setsockopt
2179 * handler, according to whether the PPPoL2TP socket is a for a regular
2180 * session or the special tunnel type.
2181 */
2182 static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
2183 char __user *optval, unsigned int optlen)
2184 {
2185 struct sock *sk = sock->sk;
2186 struct pppol2tp_session *session = sk->sk_user_data;
2187 struct pppol2tp_tunnel *tunnel;
2188 int val;
2189 int err;
2190
2191 if (level != SOL_PPPOL2TP)
2192 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
2193
2194 if (optlen < sizeof(int))
2195 return -EINVAL;
2196
2197 if (get_user(val, (int __user *)optval))
2198 return -EFAULT;
2199
2200 err = -ENOTCONN;
2201 if (sk->sk_user_data == NULL)
2202 goto end;
2203
2204 /* Get session context from the socket */
2205 err = -EBADF;
2206 session = pppol2tp_sock_to_session(sk);
2207 if (session == NULL)
2208 goto end;
2209
2210 /* Special case: if session_id == 0x0000, treat as operation on tunnel
2211 */
2212 if ((session->tunnel_addr.s_session == 0) &&
2213 (session->tunnel_addr.d_session == 0)) {
2214 err = -EBADF;
2215 tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock);
2216 if (tunnel == NULL)
2217 goto end_put_sess;
2218
2219 err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
2220 sock_put(session->tunnel_sock);
2221 } else
2222 err = pppol2tp_session_setsockopt(sk, session, optname, val);
2223
2224 err = 0;
2225
2226 end_put_sess:
2227 sock_put(sk);
2228 end:
2229 return err;
2230 }
2231
2232 /* Tunnel getsockopt helper. Called with sock locked.
2233 */
2234 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
2235 struct pppol2tp_tunnel *tunnel,
2236 int optname, int *val)
2237 {
2238 int err = 0;
2239
2240 switch (optname) {
2241 case PPPOL2TP_SO_DEBUG:
2242 *val = tunnel->debug;
2243 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2244 "%s: get debug=%x\n", tunnel->name, tunnel->debug);
2245 break;
2246
2247 default:
2248 err = -ENOPROTOOPT;
2249 break;
2250 }
2251
2252 return err;
2253 }
2254
2255 /* Session getsockopt helper. Called with sock locked.
2256 */
2257 static int pppol2tp_session_getsockopt(struct sock *sk,
2258 struct pppol2tp_session *session,
2259 int optname, int *val)
2260 {
2261 int err = 0;
2262
2263 switch (optname) {
2264 case PPPOL2TP_SO_RECVSEQ:
2265 *val = session->recv_seq;
2266 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2267 "%s: get recv_seq=%d\n", session->name, *val);
2268 break;
2269
2270 case PPPOL2TP_SO_SENDSEQ:
2271 *val = session->send_seq;
2272 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2273 "%s: get send_seq=%d\n", session->name, *val);
2274 break;
2275
2276 case PPPOL2TP_SO_LNSMODE:
2277 *val = session->lns_mode;
2278 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2279 "%s: get lns_mode=%d\n", session->name, *val);
2280 break;
2281
2282 case PPPOL2TP_SO_DEBUG:
2283 *val = session->debug;
2284 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2285 "%s: get debug=%d\n", session->name, *val);
2286 break;
2287
2288 case PPPOL2TP_SO_REORDERTO:
2289 *val = (int) jiffies_to_msecs(session->reorder_timeout);
2290 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2291 "%s: get reorder_timeout=%d\n", session->name, *val);
2292 break;
2293
2294 default:
2295 err = -ENOPROTOOPT;
2296 }
2297
2298 return err;
2299 }
2300
2301 /* Main getsockopt() entry point.
2302 * Does API checks, then calls either the tunnel or session getsockopt
2303 * handler, according to whether the PPPoX socket is a for a regular session
2304 * or the special tunnel type.
2305 */
2306 static int pppol2tp_getsockopt(struct socket *sock, int level,
2307 int optname, char __user *optval, int __user *optlen)
2308 {
2309 struct sock *sk = sock->sk;
2310 struct pppol2tp_session *session = sk->sk_user_data;
2311 struct pppol2tp_tunnel *tunnel;
2312 int val, len;
2313 int err;
2314
2315 if (level != SOL_PPPOL2TP)
2316 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
2317
2318 if (get_user(len, (int __user *) optlen))
2319 return -EFAULT;
2320
2321 len = min_t(unsigned int, len, sizeof(int));
2322
2323 if (len < 0)
2324 return -EINVAL;
2325
2326 err = -ENOTCONN;
2327 if (sk->sk_user_data == NULL)
2328 goto end;
2329
2330 /* Get the session context */
2331 err = -EBADF;
2332 session = pppol2tp_sock_to_session(sk);
2333 if (session == NULL)
2334 goto end;
2335
2336 /* Special case: if session_id == 0x0000, treat as operation on tunnel */
2337 if ((session->tunnel_addr.s_session == 0) &&
2338 (session->tunnel_addr.d_session == 0)) {
2339 err = -EBADF;
2340 tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock);
2341 if (tunnel == NULL)
2342 goto end_put_sess;
2343
2344 err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
2345 sock_put(session->tunnel_sock);
2346 } else
2347 err = pppol2tp_session_getsockopt(sk, session, optname, &val);
2348
2349 err = -EFAULT;
2350 if (put_user(len, (int __user *) optlen))
2351 goto end_put_sess;
2352
2353 if (copy_to_user((void __user *) optval, &val, len))
2354 goto end_put_sess;
2355
2356 err = 0;
2357
2358 end_put_sess:
2359 sock_put(sk);
2360 end:
2361 return err;
2362 }
2363
2364 /*****************************************************************************
2365 * /proc filesystem for debug
2366 *****************************************************************************/
2367
2368 #ifdef CONFIG_PROC_FS
2369
2370 #include <linux/seq_file.h>
2371
2372 struct pppol2tp_seq_data {
2373 struct seq_net_private p;
2374 struct pppol2tp_tunnel *tunnel; /* current tunnel */
2375 struct pppol2tp_session *session; /* NULL means get first session in tunnel */
2376 };
2377
2378 static struct pppol2tp_session *next_session(struct pppol2tp_tunnel *tunnel, struct pppol2tp_session *curr)
2379 {
2380 struct pppol2tp_session *session = NULL;
2381 struct hlist_node *walk;
2382 int found = 0;
2383 int next = 0;
2384 int i;
2385
2386 read_lock_bh(&tunnel->hlist_lock);
2387 for (i = 0; i < PPPOL2TP_HASH_SIZE; i++) {
2388 hlist_for_each_entry(session, walk, &tunnel->session_hlist[i], hlist) {
2389 if (curr == NULL) {
2390 found = 1;
2391 goto out;
2392 }
2393 if (session == curr) {
2394 next = 1;
2395 continue;
2396 }
2397 if (next) {
2398 found = 1;
2399 goto out;
2400 }
2401 }
2402 }
2403 out:
2404 read_unlock_bh(&tunnel->hlist_lock);
2405 if (!found)
2406 session = NULL;
2407
2408 return session;
2409 }
2410
2411 static struct pppol2tp_tunnel *next_tunnel(struct pppol2tp_net *pn,
2412 struct pppol2tp_tunnel *curr)
2413 {
2414 struct pppol2tp_tunnel *tunnel = NULL;
2415
2416 read_lock_bh(&pn->pppol2tp_tunnel_list_lock);
2417 if (list_is_last(&curr->list, &pn->pppol2tp_tunnel_list)) {
2418 goto out;
2419 }
2420 tunnel = list_entry(curr->list.next, struct pppol2tp_tunnel, list);
2421 out:
2422 read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
2423
2424 return tunnel;
2425 }
2426
2427 static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
2428 {
2429 struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
2430 struct pppol2tp_net *pn;
2431 loff_t pos = *offs;
2432
2433 if (!pos)
2434 goto out;
2435
2436 BUG_ON(m->private == NULL);
2437 pd = m->private;
2438 pn = pppol2tp_pernet(seq_file_net(m));
2439
2440 if (pd->tunnel == NULL) {
2441 if (!list_empty(&pn->pppol2tp_tunnel_list))
2442 pd->tunnel = list_entry(pn->pppol2tp_tunnel_list.next, struct pppol2tp_tunnel, list);
2443 } else {
2444 pd->session = next_session(pd->tunnel, pd->session);
2445 if (pd->session == NULL) {
2446 pd->tunnel = next_tunnel(pn, pd->tunnel);
2447 }
2448 }
2449
2450 /* NULL tunnel and session indicates end of list */
2451 if ((pd->tunnel == NULL) && (pd->session == NULL))
2452 pd = NULL;
2453
2454 out:
2455 return pd;
2456 }
2457
2458 static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
2459 {
2460 (*pos)++;
2461 return NULL;
2462 }
2463
2464 static void pppol2tp_seq_stop(struct seq_file *p, void *v)
2465 {
2466 /* nothing to do */
2467 }
2468
2469 static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
2470 {
2471 struct pppol2tp_tunnel *tunnel = v;
2472
2473 seq_printf(m, "\nTUNNEL '%s', %c %d\n",
2474 tunnel->name,
2475 (tunnel == tunnel->sock->sk_user_data) ? 'Y':'N',
2476 atomic_read(&tunnel->ref_count) - 1);
2477 seq_printf(m, " %08x %llu/%llu/%llu %llu/%llu/%llu\n",
2478 tunnel->debug,
2479 (unsigned long long)tunnel->stats.tx_packets,
2480 (unsigned long long)tunnel->stats.tx_bytes,
2481 (unsigned long long)tunnel->stats.tx_errors,
2482 (unsigned long long)tunnel->stats.rx_packets,
2483 (unsigned long long)tunnel->stats.rx_bytes,
2484 (unsigned long long)tunnel->stats.rx_errors);
2485 }
2486
2487 static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
2488 {
2489 struct pppol2tp_session *session = v;
2490
2491 seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
2492 "%04X/%04X %d %c\n",
2493 session->name,
2494 ntohl(session->tunnel_addr.addr.sin_addr.s_addr),
2495 ntohs(session->tunnel_addr.addr.sin_port),
2496 session->tunnel_addr.s_tunnel,
2497 session->tunnel_addr.s_session,
2498 session->tunnel_addr.d_tunnel,
2499 session->tunnel_addr.d_session,
2500 session->sock->sk_state,
2501 (session == session->sock->sk_user_data) ?
2502 'Y' : 'N');
2503 seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n",
2504 session->mtu, session->mru,
2505 session->recv_seq ? 'R' : '-',
2506 session->send_seq ? 'S' : '-',
2507 session->lns_mode ? "LNS" : "LAC",
2508 session->debug,
2509 jiffies_to_msecs(session->reorder_timeout));
2510 seq_printf(m, " %hu/%hu %llu/%llu/%llu %llu/%llu/%llu\n",
2511 session->nr, session->ns,
2512 (unsigned long long)session->stats.tx_packets,
2513 (unsigned long long)session->stats.tx_bytes,
2514 (unsigned long long)session->stats.tx_errors,
2515 (unsigned long long)session->stats.rx_packets,
2516 (unsigned long long)session->stats.rx_bytes,
2517 (unsigned long long)session->stats.rx_errors);
2518 }
2519
2520 static int pppol2tp_seq_show(struct seq_file *m, void *v)
2521 {
2522 struct pppol2tp_seq_data *pd = v;
2523
2524 /* display header on line 1 */
2525 if (v == SEQ_START_TOKEN) {
2526 seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
2527 seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
2528 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
2529 seq_puts(m, " SESSION name, addr/port src-tid/sid "
2530 "dest-tid/sid state user-data-ok\n");
2531 seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
2532 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
2533 goto out;
2534 }
2535
2536 /* Show the tunnel or session context.
2537 */
2538 if (pd->session == NULL)
2539 pppol2tp_seq_tunnel_show(m, pd->tunnel);
2540 else
2541 pppol2tp_seq_session_show(m, pd->session);
2542
2543 out:
2544 return 0;
2545 }
2546
2547 static const struct seq_operations pppol2tp_seq_ops = {
2548 .start = pppol2tp_seq_start,
2549 .next = pppol2tp_seq_next,
2550 .stop = pppol2tp_seq_stop,
2551 .show = pppol2tp_seq_show,
2552 };
2553
2554 /* Called when our /proc file is opened. We allocate data for use when
2555 * iterating our tunnel / session contexts and store it in the private
2556 * data of the seq_file.
2557 */
2558 static int pppol2tp_proc_open(struct inode *inode, struct file *file)
2559 {
2560 return seq_open_net(inode, file, &pppol2tp_seq_ops,
2561 sizeof(struct pppol2tp_seq_data));
2562 }
2563
2564 static const struct file_operations pppol2tp_proc_fops = {
2565 .owner = THIS_MODULE,
2566 .open = pppol2tp_proc_open,
2567 .read = seq_read,
2568 .llseek = seq_lseek,
2569 .release = seq_release_net,
2570 };
2571
2572 #endif /* CONFIG_PROC_FS */
2573
2574 /*****************************************************************************
2575 * Init and cleanup
2576 *****************************************************************************/
2577
2578 static const struct proto_ops pppol2tp_ops = {
2579 .family = AF_PPPOX,
2580 .owner = THIS_MODULE,
2581 .release = pppol2tp_release,
2582 .bind = sock_no_bind,
2583 .connect = pppol2tp_connect,
2584 .socketpair = sock_no_socketpair,
2585 .accept = sock_no_accept,
2586 .getname = pppol2tp_getname,
2587 .poll = datagram_poll,
2588 .listen = sock_no_listen,
2589 .shutdown = sock_no_shutdown,
2590 .setsockopt = pppol2tp_setsockopt,
2591 .getsockopt = pppol2tp_getsockopt,
2592 .sendmsg = pppol2tp_sendmsg,
2593 .recvmsg = pppol2tp_recvmsg,
2594 .mmap = sock_no_mmap,
2595 .ioctl = pppox_ioctl,
2596 };
2597
2598 static struct pppox_proto pppol2tp_proto = {
2599 .create = pppol2tp_create,
2600 .ioctl = pppol2tp_ioctl
2601 };
2602
2603 static __net_init int pppol2tp_init_net(struct net *net)
2604 {
2605 struct pppol2tp_net *pn;
2606 struct proc_dir_entry *pde;
2607 int err;
2608
2609 pn = kzalloc(sizeof(*pn), GFP_KERNEL);
2610 if (!pn)
2611 return -ENOMEM;
2612
2613 INIT_LIST_HEAD(&pn->pppol2tp_tunnel_list);
2614 rwlock_init(&pn->pppol2tp_tunnel_list_lock);
2615
2616 err = net_assign_generic(net, pppol2tp_net_id, pn);
2617 if (err)
2618 goto out;
2619
2620 pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops);
2621 #ifdef CONFIG_PROC_FS
2622 if (!pde) {
2623 err = -ENOMEM;
2624 goto out;
2625 }
2626 #endif
2627
2628 return 0;
2629
2630 out:
2631 kfree(pn);
2632 return err;
2633 }
2634
2635 static __net_exit void pppol2tp_exit_net(struct net *net)
2636 {
2637 struct pppoe_net *pn;
2638
2639 proc_net_remove(net, "pppol2tp");
2640 pn = net_generic(net, pppol2tp_net_id);
2641 /*
2642 * if someone has cached our net then
2643 * further net_generic call will return NULL
2644 */
2645 net_assign_generic(net, pppol2tp_net_id, NULL);
2646 kfree(pn);
2647 }
2648
2649 static struct pernet_operations pppol2tp_net_ops = {
2650 .init = pppol2tp_init_net,
2651 .exit = pppol2tp_exit_net,
2652 };
2653
2654 static int __init pppol2tp_init(void)
2655 {
2656 int err;
2657
2658 err = proto_register(&pppol2tp_sk_proto, 0);
2659 if (err)
2660 goto out;
2661 err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
2662 if (err)
2663 goto out_unregister_pppol2tp_proto;
2664
2665 err = register_pernet_gen_device(&pppol2tp_net_id, &pppol2tp_net_ops);
2666 if (err)
2667 goto out_unregister_pppox_proto;
2668
2669 printk(KERN_INFO "PPPoL2TP kernel driver, %s\n",
2670 PPPOL2TP_DRV_VERSION);
2671
2672 out:
2673 return err;
2674 out_unregister_pppox_proto:
2675 unregister_pppox_proto(PX_PROTO_OL2TP);
2676 out_unregister_pppol2tp_proto:
2677 proto_unregister(&pppol2tp_sk_proto);
2678 goto out;
2679 }
2680
2681 static void __exit pppol2tp_exit(void)
2682 {
2683 unregister_pppox_proto(PX_PROTO_OL2TP);
2684 unregister_pernet_gen_device(pppol2tp_net_id, &pppol2tp_net_ops);
2685 proto_unregister(&pppol2tp_sk_proto);
2686 }
2687
2688 module_init(pppol2tp_init);
2689 module_exit(pppol2tp_exit);
2690
2691 MODULE_AUTHOR("Martijn van Oosterhout <kleptog@svana.org>, "
2692 "James Chapman <jchapman@katalix.com>");
2693 MODULE_DESCRIPTION("PPP over L2TP over UDP");
2694 MODULE_LICENSE("GPL");
2695 MODULE_VERSION(PPPOL2TP_DRV_VERSION);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree