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Audit: move audit_get_nd completely into audit_watch
[linux-2.6/mini2440.git] / drivers / net / pppol2tp.c
blobe7935d09c896786083606cc23d962a6504aed9a5
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 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)->dev->features & NETIF_F_V4_CSUM)) {
1182 skb->ip_summed = CHECKSUM_COMPLETE;
1183 csum = skb_checksum(skb, 0, udp_len, 0);
1184 uh->check = csum_tcpudp_magic(inet->saddr, inet->daddr,
1185 udp_len, IPPROTO_UDP, csum);
1186 if (uh->check == 0)
1187 uh->check = CSUM_MANGLED_0;
1188 } else {
1189 skb->ip_summed = CHECKSUM_PARTIAL;
1190 skb->csum_start = skb_transport_header(skb) - skb->head;
1191 skb->csum_offset = offsetof(struct udphdr, check);
1192 uh->check = ~csum_tcpudp_magic(inet->saddr, inet->daddr,
1193 udp_len, IPPROTO_UDP, 0);
1194 }
1195
1196 /* Queue the packet to IP for output */
1197 len = skb->len;
1198 rc = ip_queue_xmit(skb, 1);
1199
1200 /* Update stats */
1201 if (rc >= 0) {
1202 tunnel->stats.tx_packets++;
1203 tunnel->stats.tx_bytes += len;
1204 session->stats.tx_packets++;
1205 session->stats.tx_bytes += len;
1206 } else {
1207 tunnel->stats.tx_errors++;
1208 session->stats.tx_errors++;
1209 }
1210
1211 sock_put(sk_tun);
1212 sock_put(sk);
1213 return 1;
1214
1215 abort_put_sess_tun:
1216 sock_put(sk_tun);
1217 abort_put_sess:
1218 sock_put(sk);
1219 abort:
1220 /* Free the original skb */
1221 kfree_skb(skb);
1222 return 1;
1223 }
1224
1225 /*****************************************************************************
1226 * Session (and tunnel control) socket create/destroy.
1227 *****************************************************************************/
1228
1229 /* When the tunnel UDP socket is closed, all the attached sockets need to go
1230 * too.
1231 */
1232 static void pppol2tp_tunnel_closeall(struct pppol2tp_tunnel *tunnel)
1233 {
1234 int hash;
1235 struct hlist_node *walk;
1236 struct hlist_node *tmp;
1237 struct pppol2tp_session *session;
1238 struct sock *sk;
1239
1240 BUG_ON(tunnel == NULL);
1241
1242 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1243 "%s: closing all sessions...\n", tunnel->name);
1244
1245 write_lock_bh(&tunnel->hlist_lock);
1246 for (hash = 0; hash < PPPOL2TP_HASH_SIZE; hash++) {
1247 again:
1248 hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
1249 struct sk_buff *skb;
1250
1251 session = hlist_entry(walk, struct pppol2tp_session, hlist);
1252
1253 sk = session->sock;
1254
1255 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1256 "%s: closing session\n", session->name);
1257
1258 hlist_del_init(&session->hlist);
1259
1260 /* Since we should hold the sock lock while
1261 * doing any unbinding, we need to release the
1262 * lock we're holding before taking that lock.
1263 * Hold a reference to the sock so it doesn't
1264 * disappear as we're jumping between locks.
1265 */
1266 sock_hold(sk);
1267 write_unlock_bh(&tunnel->hlist_lock);
1268 lock_sock(sk);
1269
1270 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
1271 pppox_unbind_sock(sk);
1272 sk->sk_state = PPPOX_DEAD;
1273 sk->sk_state_change(sk);
1274 }
1275
1276 /* Purge any queued data */
1277 skb_queue_purge(&sk->sk_receive_queue);
1278 skb_queue_purge(&sk->sk_write_queue);
1279 while ((skb = skb_dequeue(&session->reorder_q))) {
1280 kfree_skb(skb);
1281 sock_put(sk);
1282 }
1283
1284 release_sock(sk);
1285 sock_put(sk);
1286
1287 /* Now restart from the beginning of this hash
1288 * chain. We always remove a session from the
1289 * list so we are guaranteed to make forward
1290 * progress.
1291 */
1292 write_lock_bh(&tunnel->hlist_lock);
1293 goto again;
1294 }
1295 }
1296 write_unlock_bh(&tunnel->hlist_lock);
1297 }
1298
1299 /* Really kill the tunnel.
1300 * Come here only when all sessions have been cleared from the tunnel.
1301 */
1302 static void pppol2tp_tunnel_free(struct pppol2tp_tunnel *tunnel)
1303 {
1304 struct pppol2tp_net *pn = pppol2tp_pernet(tunnel->pppol2tp_net);
1305
1306 /* Remove from socket list */
1307 write_lock_bh(&pn->pppol2tp_tunnel_list_lock);
1308 list_del_init(&tunnel->list);
1309 write_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
1310
1311 atomic_dec(&pppol2tp_tunnel_count);
1312 kfree(tunnel);
1313 }
1314
1315 /* Tunnel UDP socket destruct hook.
1316 * The tunnel context is deleted only when all session sockets have been
1317 * closed.
1318 */
1319 static void pppol2tp_tunnel_destruct(struct sock *sk)
1320 {
1321 struct pppol2tp_tunnel *tunnel;
1322
1323 tunnel = sk->sk_user_data;
1324 if (tunnel == NULL)
1325 goto end;
1326
1327 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1328 "%s: closing...\n", tunnel->name);
1329
1330 /* Close all sessions */
1331 pppol2tp_tunnel_closeall(tunnel);
1332
1333 /* No longer an encapsulation socket. See net/ipv4/udp.c */
1334 (udp_sk(sk))->encap_type = 0;
1335 (udp_sk(sk))->encap_rcv = NULL;
1336
1337 /* Remove hooks into tunnel socket */
1338 tunnel->sock = NULL;
1339 sk->sk_destruct = tunnel->old_sk_destruct;
1340 sk->sk_user_data = NULL;
1341
1342 /* Call original (UDP) socket descructor */
1343 if (sk->sk_destruct != NULL)
1344 (*sk->sk_destruct)(sk);
1345
1346 pppol2tp_tunnel_dec_refcount(tunnel);
1347
1348 end:
1349 return;
1350 }
1351
1352 /* Really kill the session socket. (Called from sock_put() if
1353 * refcnt == 0.)
1354 */
1355 static void pppol2tp_session_destruct(struct sock *sk)
1356 {
1357 struct pppol2tp_session *session = NULL;
1358
1359 if (sk->sk_user_data != NULL) {
1360 struct pppol2tp_tunnel *tunnel;
1361
1362 session = sk->sk_user_data;
1363 if (session == NULL)
1364 goto out;
1365
1366 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
1367
1368 /* Don't use pppol2tp_sock_to_tunnel() here to
1369 * get the tunnel context because the tunnel
1370 * socket might have already been closed (its
1371 * sk->sk_user_data will be NULL) so use the
1372 * session's private tunnel ptr instead.
1373 */
1374 tunnel = session->tunnel;
1375 if (tunnel != NULL) {
1376 BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
1377
1378 /* If session_id is zero, this is a null
1379 * session context, which was created for a
1380 * socket that is being used only to manage
1381 * tunnels.
1382 */
1383 if (session->tunnel_addr.s_session != 0) {
1384 /* Delete the session socket from the
1385 * hash
1386 */
1387 write_lock_bh(&tunnel->hlist_lock);
1388 hlist_del_init(&session->hlist);
1389 write_unlock_bh(&tunnel->hlist_lock);
1390
1391 atomic_dec(&pppol2tp_session_count);
1392 }
1393
1394 /* This will delete the tunnel context if this
1395 * is the last session on the tunnel.
1396 */
1397 session->tunnel = NULL;
1398 session->tunnel_sock = NULL;
1399 pppol2tp_tunnel_dec_refcount(tunnel);
1400 }
1401 }
1402
1403 kfree(session);
1404 out:
1405 return;
1406 }
1407
1408 /* Called when the PPPoX socket (session) is closed.
1409 */
1410 static int pppol2tp_release(struct socket *sock)
1411 {
1412 struct sock *sk = sock->sk;
1413 struct pppol2tp_session *session;
1414 int error;
1415
1416 if (!sk)
1417 return 0;
1418
1419 error = -EBADF;
1420 lock_sock(sk);
1421 if (sock_flag(sk, SOCK_DEAD) != 0)
1422 goto error;
1423
1424 pppox_unbind_sock(sk);
1425
1426 /* Signal the death of the socket. */
1427 sk->sk_state = PPPOX_DEAD;
1428 sock_orphan(sk);
1429 sock->sk = NULL;
1430
1431 session = pppol2tp_sock_to_session(sk);
1432
1433 /* Purge any queued data */
1434 skb_queue_purge(&sk->sk_receive_queue);
1435 skb_queue_purge(&sk->sk_write_queue);
1436 if (session != NULL) {
1437 struct sk_buff *skb;
1438 while ((skb = skb_dequeue(&session->reorder_q))) {
1439 kfree_skb(skb);
1440 sock_put(sk);
1441 }
1442 sock_put(sk);
1443 }
1444
1445 release_sock(sk);
1446
1447 /* This will delete the session context via
1448 * pppol2tp_session_destruct() if the socket's refcnt drops to
1449 * zero.
1450 */
1451 sock_put(sk);
1452
1453 return 0;
1454
1455 error:
1456 release_sock(sk);
1457 return error;
1458 }
1459
1460 /* Internal function to prepare a tunnel (UDP) socket to have PPPoX
1461 * sockets attached to it.
1462 */
1463 static struct sock *pppol2tp_prepare_tunnel_socket(struct net *net,
1464 int fd, u16 tunnel_id, int *error)
1465 {
1466 int err;
1467 struct socket *sock = NULL;
1468 struct sock *sk;
1469 struct pppol2tp_tunnel *tunnel;
1470 struct pppol2tp_net *pn;
1471 struct sock *ret = NULL;
1472
1473 /* Get the tunnel UDP socket from the fd, which was opened by
1474 * the userspace L2TP daemon.
1475 */
1476 err = -EBADF;
1477 sock = sockfd_lookup(fd, &err);
1478 if (!sock) {
1479 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR,
1480 "tunl %hu: sockfd_lookup(fd=%d) returned %d\n",
1481 tunnel_id, fd, err);
1482 goto err;
1483 }
1484
1485 sk = sock->sk;
1486
1487 /* Quick sanity checks */
1488 err = -EPROTONOSUPPORT;
1489 if (sk->sk_protocol != IPPROTO_UDP) {
1490 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR,
1491 "tunl %hu: fd %d wrong protocol, got %d, expected %d\n",
1492 tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP);
1493 goto err;
1494 }
1495 err = -EAFNOSUPPORT;
1496 if (sock->ops->family != AF_INET) {
1497 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR,
1498 "tunl %hu: fd %d wrong family, got %d, expected %d\n",
1499 tunnel_id, fd, sock->ops->family, AF_INET);
1500 goto err;
1501 }
1502
1503 err = -ENOTCONN;
1504
1505 /* Check if this socket has already been prepped */
1506 tunnel = (struct pppol2tp_tunnel *)sk->sk_user_data;
1507 if (tunnel != NULL) {
1508 /* User-data field already set */
1509 err = -EBUSY;
1510 BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
1511
1512 /* This socket has already been prepped */
1513 ret = tunnel->sock;
1514 goto out;
1515 }
1516
1517 /* This socket is available and needs prepping. Create a new tunnel
1518 * context and init it.
1519 */
1520 sk->sk_user_data = tunnel = kzalloc(sizeof(struct pppol2tp_tunnel), GFP_KERNEL);
1521 if (sk->sk_user_data == NULL) {
1522 err = -ENOMEM;
1523 goto err;
1524 }
1525
1526 tunnel->magic = L2TP_TUNNEL_MAGIC;
1527 sprintf(&tunnel->name[0], "tunl %hu", tunnel_id);
1528
1529 tunnel->stats.tunnel_id = tunnel_id;
1530 tunnel->debug = PPPOL2TP_DEFAULT_DEBUG_FLAGS;
1531
1532 /* Hook on the tunnel socket destructor so that we can cleanup
1533 * if the tunnel socket goes away.
1534 */
1535 tunnel->old_sk_destruct = sk->sk_destruct;
1536 sk->sk_destruct = &pppol2tp_tunnel_destruct;
1537
1538 tunnel->sock = sk;
1539 sk->sk_allocation = GFP_ATOMIC;
1540
1541 /* Misc init */
1542 rwlock_init(&tunnel->hlist_lock);
1543
1544 /* The net we belong to */
1545 tunnel->pppol2tp_net = net;
1546 pn = pppol2tp_pernet(net);
1547
1548 /* Add tunnel to our list */
1549 INIT_LIST_HEAD(&tunnel->list);
1550 write_lock_bh(&pn->pppol2tp_tunnel_list_lock);
1551 list_add(&tunnel->list, &pn->pppol2tp_tunnel_list);
1552 write_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
1553 atomic_inc(&pppol2tp_tunnel_count);
1554
1555 /* Bump the reference count. The tunnel context is deleted
1556 * only when this drops to zero.
1557 */
1558 pppol2tp_tunnel_inc_refcount(tunnel);
1559
1560 /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */
1561 (udp_sk(sk))->encap_type = UDP_ENCAP_L2TPINUDP;
1562 (udp_sk(sk))->encap_rcv = pppol2tp_udp_encap_recv;
1563
1564 ret = tunnel->sock;
1565
1566 *error = 0;
1567 out:
1568 if (sock)
1569 sockfd_put(sock);
1570
1571 return ret;
1572
1573 err:
1574 *error = err;
1575 goto out;
1576 }
1577
1578 static struct proto pppol2tp_sk_proto = {
1579 .name = "PPPOL2TP",
1580 .owner = THIS_MODULE,
1581 .obj_size = sizeof(struct pppox_sock),
1582 };
1583
1584 /* socket() handler. Initialize a new struct sock.
1585 */
1586 static int pppol2tp_create(struct net *net, struct socket *sock)
1587 {
1588 int error = -ENOMEM;
1589 struct sock *sk;
1590
1591 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto);
1592 if (!sk)
1593 goto out;
1594
1595 sock_init_data(sock, sk);
1596
1597 sock->state = SS_UNCONNECTED;
1598 sock->ops = &pppol2tp_ops;
1599
1600 sk->sk_backlog_rcv = pppol2tp_recv_core;
1601 sk->sk_protocol = PX_PROTO_OL2TP;
1602 sk->sk_family = PF_PPPOX;
1603 sk->sk_state = PPPOX_NONE;
1604 sk->sk_type = SOCK_STREAM;
1605 sk->sk_destruct = pppol2tp_session_destruct;
1606
1607 error = 0;
1608
1609 out:
1610 return error;
1611 }
1612
1613 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
1614 */
1615 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
1616 int sockaddr_len, int flags)
1617 {
1618 struct sock *sk = sock->sk;
1619 struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
1620 struct pppox_sock *po = pppox_sk(sk);
1621 struct sock *tunnel_sock = NULL;
1622 struct pppol2tp_session *session = NULL;
1623 struct pppol2tp_tunnel *tunnel;
1624 struct dst_entry *dst;
1625 int error = 0;
1626
1627 lock_sock(sk);
1628
1629 error = -EINVAL;
1630 if (sp->sa_protocol != PX_PROTO_OL2TP)
1631 goto end;
1632
1633 /* Check for already bound sockets */
1634 error = -EBUSY;
1635 if (sk->sk_state & PPPOX_CONNECTED)
1636 goto end;
1637
1638 /* We don't supporting rebinding anyway */
1639 error = -EALREADY;
1640 if (sk->sk_user_data)
1641 goto end; /* socket is already attached */
1642
1643 /* Don't bind if s_tunnel is 0 */
1644 error = -EINVAL;
1645 if (sp->pppol2tp.s_tunnel == 0)
1646 goto end;
1647
1648 /* Special case: prepare tunnel socket if s_session and
1649 * d_session is 0. Otherwise look up tunnel using supplied
1650 * tunnel id.
1651 */
1652 if ((sp->pppol2tp.s_session == 0) && (sp->pppol2tp.d_session == 0)) {
1653 tunnel_sock = pppol2tp_prepare_tunnel_socket(sock_net(sk),
1654 sp->pppol2tp.fd,
1655 sp->pppol2tp.s_tunnel,
1656 &error);
1657 if (tunnel_sock == NULL)
1658 goto end;
1659
1660 tunnel = tunnel_sock->sk_user_data;
1661 } else {
1662 tunnel = pppol2tp_tunnel_find(sock_net(sk), sp->pppol2tp.s_tunnel);
1663
1664 /* Error if we can't find the tunnel */
1665 error = -ENOENT;
1666 if (tunnel == NULL)
1667 goto end;
1668
1669 tunnel_sock = tunnel->sock;
1670 }
1671
1672 /* Check that this session doesn't already exist */
1673 error = -EEXIST;
1674 session = pppol2tp_session_find(tunnel, sp->pppol2tp.s_session);
1675 if (session != NULL)
1676 goto end;
1677
1678 /* Allocate and initialize a new session context. */
1679 session = kzalloc(sizeof(struct pppol2tp_session), GFP_KERNEL);
1680 if (session == NULL) {
1681 error = -ENOMEM;
1682 goto end;
1683 }
1684
1685 skb_queue_head_init(&session->reorder_q);
1686
1687 session->magic = L2TP_SESSION_MAGIC;
1688 session->owner = current->pid;
1689 session->sock = sk;
1690 session->tunnel = tunnel;
1691 session->tunnel_sock = tunnel_sock;
1692 session->tunnel_addr = sp->pppol2tp;
1693 sprintf(&session->name[0], "sess %hu/%hu",
1694 session->tunnel_addr.s_tunnel,
1695 session->tunnel_addr.s_session);
1696
1697 session->stats.tunnel_id = session->tunnel_addr.s_tunnel;
1698 session->stats.session_id = session->tunnel_addr.s_session;
1699
1700 INIT_HLIST_NODE(&session->hlist);
1701
1702 /* Inherit debug options from tunnel */
1703 session->debug = tunnel->debug;
1704
1705 /* Default MTU must allow space for UDP/L2TP/PPP
1706 * headers.
1707 */
1708 session->mtu = session->mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
1709
1710 /* If PMTU discovery was enabled, use the MTU that was discovered */
1711 dst = sk_dst_get(sk);
1712 if (dst != NULL) {
1713 u32 pmtu = dst_mtu(__sk_dst_get(sk));
1714 if (pmtu != 0)
1715 session->mtu = session->mru = pmtu -
1716 PPPOL2TP_HEADER_OVERHEAD;
1717 dst_release(dst);
1718 }
1719
1720 /* Special case: if source & dest session_id == 0x0000, this socket is
1721 * being created to manage the tunnel. Don't add the session to the
1722 * session hash list, just set up the internal context for use by
1723 * ioctl() and sockopt() handlers.
1724 */
1725 if ((session->tunnel_addr.s_session == 0) &&
1726 (session->tunnel_addr.d_session == 0)) {
1727 error = 0;
1728 sk->sk_user_data = session;
1729 goto out_no_ppp;
1730 }
1731
1732 /* Get tunnel context from the tunnel socket */
1733 tunnel = pppol2tp_sock_to_tunnel(tunnel_sock);
1734 if (tunnel == NULL) {
1735 error = -EBADF;
1736 goto end;
1737 }
1738
1739 /* Right now, because we don't have a way to push the incoming skb's
1740 * straight through the UDP layer, the only header we need to worry
1741 * about is the L2TP header. This size is different depending on
1742 * whether sequence numbers are enabled for the data channel.
1743 */
1744 po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
1745
1746 po->chan.private = sk;
1747 po->chan.ops = &pppol2tp_chan_ops;
1748 po->chan.mtu = session->mtu;
1749
1750 error = ppp_register_net_channel(sock_net(sk), &po->chan);
1751 if (error)
1752 goto end_put_tun;
1753
1754 /* This is how we get the session context from the socket. */
1755 sk->sk_user_data = session;
1756
1757 /* Add session to the tunnel's hash list */
1758 write_lock_bh(&tunnel->hlist_lock);
1759 hlist_add_head(&session->hlist,
1760 pppol2tp_session_id_hash(tunnel,
1761 session->tunnel_addr.s_session));
1762 write_unlock_bh(&tunnel->hlist_lock);
1763
1764 atomic_inc(&pppol2tp_session_count);
1765
1766 out_no_ppp:
1767 pppol2tp_tunnel_inc_refcount(tunnel);
1768 sk->sk_state = PPPOX_CONNECTED;
1769 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1770 "%s: created\n", session->name);
1771
1772 end_put_tun:
1773 sock_put(tunnel_sock);
1774 end:
1775 release_sock(sk);
1776
1777 if (error != 0) {
1778 if (session)
1779 PRINTK(session->debug,
1780 PPPOL2TP_MSG_CONTROL, KERN_WARNING,
1781 "%s: connect failed: %d\n",
1782 session->name, error);
1783 else
1784 PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_WARNING,
1785 "connect failed: %d\n", error);
1786 }
1787
1788 return error;
1789 }
1790
1791 /* getname() support.
1792 */
1793 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
1794 int *usockaddr_len, int peer)
1795 {
1796 int len = sizeof(struct sockaddr_pppol2tp);
1797 struct sockaddr_pppol2tp sp;
1798 int error = 0;
1799 struct pppol2tp_session *session;
1800
1801 error = -ENOTCONN;
1802 if (sock->sk->sk_state != PPPOX_CONNECTED)
1803 goto end;
1804
1805 session = pppol2tp_sock_to_session(sock->sk);
1806 if (session == NULL) {
1807 error = -EBADF;
1808 goto end;
1809 }
1810
1811 sp.sa_family = AF_PPPOX;
1812 sp.sa_protocol = PX_PROTO_OL2TP;
1813 memcpy(&sp.pppol2tp, &session->tunnel_addr,
1814 sizeof(struct pppol2tp_addr));
1815
1816 memcpy(uaddr, &sp, len);
1817
1818 *usockaddr_len = len;
1819
1820 error = 0;
1821 sock_put(sock->sk);
1822
1823 end:
1824 return error;
1825 }
1826
1827 /****************************************************************************
1828 * ioctl() handlers.
1829 *
1830 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1831 * sockets. However, in order to control kernel tunnel features, we allow
1832 * userspace to create a special "tunnel" PPPoX socket which is used for
1833 * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
1834 * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
1835 * calls.
1836 ****************************************************************************/
1837
1838 /* Session ioctl helper.
1839 */
1840 static int pppol2tp_session_ioctl(struct pppol2tp_session *session,
1841 unsigned int cmd, unsigned long arg)
1842 {
1843 struct ifreq ifr;
1844 int err = 0;
1845 struct sock *sk = session->sock;
1846 int val = (int) arg;
1847
1848 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1849 "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n",
1850 session->name, cmd, arg);
1851
1852 sock_hold(sk);
1853
1854 switch (cmd) {
1855 case SIOCGIFMTU:
1856 err = -ENXIO;
1857 if (!(sk->sk_state & PPPOX_CONNECTED))
1858 break;
1859
1860 err = -EFAULT;
1861 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1862 break;
1863 ifr.ifr_mtu = session->mtu;
1864 if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq)))
1865 break;
1866
1867 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1868 "%s: get mtu=%d\n", session->name, session->mtu);
1869 err = 0;
1870 break;
1871
1872 case SIOCSIFMTU:
1873 err = -ENXIO;
1874 if (!(sk->sk_state & PPPOX_CONNECTED))
1875 break;
1876
1877 err = -EFAULT;
1878 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1879 break;
1880
1881 session->mtu = ifr.ifr_mtu;
1882
1883 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1884 "%s: set mtu=%d\n", session->name, session->mtu);
1885 err = 0;
1886 break;
1887
1888 case PPPIOCGMRU:
1889 err = -ENXIO;
1890 if (!(sk->sk_state & PPPOX_CONNECTED))
1891 break;
1892
1893 err = -EFAULT;
1894 if (put_user(session->mru, (int __user *) arg))
1895 break;
1896
1897 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1898 "%s: get mru=%d\n", session->name, session->mru);
1899 err = 0;
1900 break;
1901
1902 case PPPIOCSMRU:
1903 err = -ENXIO;
1904 if (!(sk->sk_state & PPPOX_CONNECTED))
1905 break;
1906
1907 err = -EFAULT;
1908 if (get_user(val,(int __user *) arg))
1909 break;
1910
1911 session->mru = val;
1912 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1913 "%s: set mru=%d\n", session->name, session->mru);
1914 err = 0;
1915 break;
1916
1917 case PPPIOCGFLAGS:
1918 err = -EFAULT;
1919 if (put_user(session->flags, (int __user *) arg))
1920 break;
1921
1922 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1923 "%s: get flags=%d\n", session->name, session->flags);
1924 err = 0;
1925 break;
1926
1927 case PPPIOCSFLAGS:
1928 err = -EFAULT;
1929 if (get_user(val, (int __user *) arg))
1930 break;
1931 session->flags = val;
1932 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1933 "%s: set flags=%d\n", session->name, session->flags);
1934 err = 0;
1935 break;
1936
1937 case PPPIOCGL2TPSTATS:
1938 err = -ENXIO;
1939 if (!(sk->sk_state & PPPOX_CONNECTED))
1940 break;
1941
1942 if (copy_to_user((void __user *) arg, &session->stats,
1943 sizeof(session->stats)))
1944 break;
1945 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1946 "%s: get L2TP stats\n", session->name);
1947 err = 0;
1948 break;
1949
1950 default:
1951 err = -ENOSYS;
1952 break;
1953 }
1954
1955 sock_put(sk);
1956
1957 return err;
1958 }
1959
1960 /* Tunnel ioctl helper.
1961 *
1962 * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data
1963 * specifies a session_id, the session ioctl handler is called. This allows an
1964 * application to retrieve session stats via a tunnel socket.
1965 */
1966 static int pppol2tp_tunnel_ioctl(struct pppol2tp_tunnel *tunnel,
1967 unsigned int cmd, unsigned long arg)
1968 {
1969 int err = 0;
1970 struct sock *sk = tunnel->sock;
1971 struct pppol2tp_ioc_stats stats_req;
1972
1973 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1974 "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n", tunnel->name,
1975 cmd, arg);
1976
1977 sock_hold(sk);
1978
1979 switch (cmd) {
1980 case PPPIOCGL2TPSTATS:
1981 err = -ENXIO;
1982 if (!(sk->sk_state & PPPOX_CONNECTED))
1983 break;
1984
1985 if (copy_from_user(&stats_req, (void __user *) arg,
1986 sizeof(stats_req))) {
1987 err = -EFAULT;
1988 break;
1989 }
1990 if (stats_req.session_id != 0) {
1991 /* resend to session ioctl handler */
1992 struct pppol2tp_session *session =
1993 pppol2tp_session_find(tunnel, stats_req.session_id);
1994 if (session != NULL)
1995 err = pppol2tp_session_ioctl(session, cmd, arg);
1996 else
1997 err = -EBADR;
1998 break;
1999 }
2000 #ifdef CONFIG_XFRM
2001 tunnel->stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0;
2002 #endif
2003 if (copy_to_user((void __user *) arg, &tunnel->stats,
2004 sizeof(tunnel->stats))) {
2005 err = -EFAULT;
2006 break;
2007 }
2008 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2009 "%s: get L2TP stats\n", tunnel->name);
2010 err = 0;
2011 break;
2012
2013 default:
2014 err = -ENOSYS;
2015 break;
2016 }
2017
2018 sock_put(sk);
2019
2020 return err;
2021 }
2022
2023 /* Main ioctl() handler.
2024 * Dispatch to tunnel or session helpers depending on the socket.
2025 */
2026 static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
2027 unsigned long arg)
2028 {
2029 struct sock *sk = sock->sk;
2030 struct pppol2tp_session *session;
2031 struct pppol2tp_tunnel *tunnel;
2032 int err;
2033
2034 if (!sk)
2035 return 0;
2036
2037 err = -EBADF;
2038 if (sock_flag(sk, SOCK_DEAD) != 0)
2039 goto end;
2040
2041 err = -ENOTCONN;
2042 if ((sk->sk_user_data == NULL) ||
2043 (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND))))
2044 goto end;
2045
2046 /* Get session context from the socket */
2047 err = -EBADF;
2048 session = pppol2tp_sock_to_session(sk);
2049 if (session == NULL)
2050 goto end;
2051
2052 /* Special case: if session's session_id is zero, treat ioctl as a
2053 * tunnel ioctl
2054 */
2055 if ((session->tunnel_addr.s_session == 0) &&
2056 (session->tunnel_addr.d_session == 0)) {
2057 err = -EBADF;
2058 tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock);
2059 if (tunnel == NULL)
2060 goto end_put_sess;
2061
2062 err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
2063 sock_put(session->tunnel_sock);
2064 goto end_put_sess;
2065 }
2066
2067 err = pppol2tp_session_ioctl(session, cmd, arg);
2068
2069 end_put_sess:
2070 sock_put(sk);
2071 end:
2072 return err;
2073 }
2074
2075 /*****************************************************************************
2076 * setsockopt() / getsockopt() support.
2077 *
2078 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
2079 * sockets. In order to control kernel tunnel features, we allow userspace to
2080 * create a special "tunnel" PPPoX socket which is used for control only.
2081 * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
2082 * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
2083 *****************************************************************************/
2084
2085 /* Tunnel setsockopt() helper.
2086 */
2087 static int pppol2tp_tunnel_setsockopt(struct sock *sk,
2088 struct pppol2tp_tunnel *tunnel,
2089 int optname, int val)
2090 {
2091 int err = 0;
2092
2093 switch (optname) {
2094 case PPPOL2TP_SO_DEBUG:
2095 tunnel->debug = val;
2096 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2097 "%s: set debug=%x\n", tunnel->name, tunnel->debug);
2098 break;
2099
2100 default:
2101 err = -ENOPROTOOPT;
2102 break;
2103 }
2104
2105 return err;
2106 }
2107
2108 /* Session setsockopt helper.
2109 */
2110 static int pppol2tp_session_setsockopt(struct sock *sk,
2111 struct pppol2tp_session *session,
2112 int optname, int val)
2113 {
2114 int err = 0;
2115
2116 switch (optname) {
2117 case PPPOL2TP_SO_RECVSEQ:
2118 if ((val != 0) && (val != 1)) {
2119 err = -EINVAL;
2120 break;
2121 }
2122 session->recv_seq = val ? -1 : 0;
2123 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2124 "%s: set recv_seq=%d\n", session->name,
2125 session->recv_seq);
2126 break;
2127
2128 case PPPOL2TP_SO_SENDSEQ:
2129 if ((val != 0) && (val != 1)) {
2130 err = -EINVAL;
2131 break;
2132 }
2133 session->send_seq = val ? -1 : 0;
2134 {
2135 struct sock *ssk = session->sock;
2136 struct pppox_sock *po = pppox_sk(ssk);
2137 po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
2138 PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
2139 }
2140 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2141 "%s: set send_seq=%d\n", session->name, session->send_seq);
2142 break;
2143
2144 case PPPOL2TP_SO_LNSMODE:
2145 if ((val != 0) && (val != 1)) {
2146 err = -EINVAL;
2147 break;
2148 }
2149 session->lns_mode = val ? -1 : 0;
2150 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2151 "%s: set lns_mode=%d\n", session->name,
2152 session->lns_mode);
2153 break;
2154
2155 case PPPOL2TP_SO_DEBUG:
2156 session->debug = val;
2157 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2158 "%s: set debug=%x\n", session->name, session->debug);
2159 break;
2160
2161 case PPPOL2TP_SO_REORDERTO:
2162 session->reorder_timeout = msecs_to_jiffies(val);
2163 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2164 "%s: set reorder_timeout=%d\n", session->name,
2165 session->reorder_timeout);
2166 break;
2167
2168 default:
2169 err = -ENOPROTOOPT;
2170 break;
2171 }
2172
2173 return err;
2174 }
2175
2176 /* Main setsockopt() entry point.
2177 * Does API checks, then calls either the tunnel or session setsockopt
2178 * handler, according to whether the PPPoL2TP socket is a for a regular
2179 * session or the special tunnel type.
2180 */
2181 static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
2182 char __user *optval, int optlen)
2183 {
2184 struct sock *sk = sock->sk;
2185 struct pppol2tp_session *session = sk->sk_user_data;
2186 struct pppol2tp_tunnel *tunnel;
2187 int val;
2188 int err;
2189
2190 if (level != SOL_PPPOL2TP)
2191 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
2192
2193 if (optlen < sizeof(int))
2194 return -EINVAL;
2195
2196 if (get_user(val, (int __user *)optval))
2197 return -EFAULT;
2198
2199 err = -ENOTCONN;
2200 if (sk->sk_user_data == NULL)
2201 goto end;
2202
2203 /* Get session context from the socket */
2204 err = -EBADF;
2205 session = pppol2tp_sock_to_session(sk);
2206 if (session == NULL)
2207 goto end;
2208
2209 /* Special case: if session_id == 0x0000, treat as operation on tunnel
2210 */
2211 if ((session->tunnel_addr.s_session == 0) &&
2212 (session->tunnel_addr.d_session == 0)) {
2213 err = -EBADF;
2214 tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock);
2215 if (tunnel == NULL)
2216 goto end_put_sess;
2217
2218 err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
2219 sock_put(session->tunnel_sock);
2220 } else
2221 err = pppol2tp_session_setsockopt(sk, session, optname, val);
2222
2223 err = 0;
2224
2225 end_put_sess:
2226 sock_put(sk);
2227 end:
2228 return err;
2229 }
2230
2231 /* Tunnel getsockopt helper. Called with sock locked.
2232 */
2233 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
2234 struct pppol2tp_tunnel *tunnel,
2235 int optname, int *val)
2236 {
2237 int err = 0;
2238
2239 switch (optname) {
2240 case PPPOL2TP_SO_DEBUG:
2241 *val = tunnel->debug;
2242 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2243 "%s: get debug=%x\n", tunnel->name, tunnel->debug);
2244 break;
2245
2246 default:
2247 err = -ENOPROTOOPT;
2248 break;
2249 }
2250
2251 return err;
2252 }
2253
2254 /* Session getsockopt helper. Called with sock locked.
2255 */
2256 static int pppol2tp_session_getsockopt(struct sock *sk,
2257 struct pppol2tp_session *session,
2258 int optname, int *val)
2259 {
2260 int err = 0;
2261
2262 switch (optname) {
2263 case PPPOL2TP_SO_RECVSEQ:
2264 *val = session->recv_seq;
2265 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2266 "%s: get recv_seq=%d\n", session->name, *val);
2267 break;
2268
2269 case PPPOL2TP_SO_SENDSEQ:
2270 *val = session->send_seq;
2271 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2272 "%s: get send_seq=%d\n", session->name, *val);
2273 break;
2274
2275 case PPPOL2TP_SO_LNSMODE:
2276 *val = session->lns_mode;
2277 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2278 "%s: get lns_mode=%d\n", session->name, *val);
2279 break;
2280
2281 case PPPOL2TP_SO_DEBUG:
2282 *val = session->debug;
2283 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2284 "%s: get debug=%d\n", session->name, *val);
2285 break;
2286
2287 case PPPOL2TP_SO_REORDERTO:
2288 *val = (int) jiffies_to_msecs(session->reorder_timeout);
2289 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
2290 "%s: get reorder_timeout=%d\n", session->name, *val);
2291 break;
2292
2293 default:
2294 err = -ENOPROTOOPT;
2295 }
2296
2297 return err;
2298 }
2299
2300 /* Main getsockopt() entry point.
2301 * Does API checks, then calls either the tunnel or session getsockopt
2302 * handler, according to whether the PPPoX socket is a for a regular session
2303 * or the special tunnel type.
2304 */
2305 static int pppol2tp_getsockopt(struct socket *sock, int level,
2306 int optname, char __user *optval, int __user *optlen)
2307 {
2308 struct sock *sk = sock->sk;
2309 struct pppol2tp_session *session = sk->sk_user_data;
2310 struct pppol2tp_tunnel *tunnel;
2311 int val, len;
2312 int err;
2313
2314 if (level != SOL_PPPOL2TP)
2315 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
2316
2317 if (get_user(len, (int __user *) optlen))
2318 return -EFAULT;
2319
2320 len = min_t(unsigned int, len, sizeof(int));
2321
2322 if (len < 0)
2323 return -EINVAL;
2324
2325 err = -ENOTCONN;
2326 if (sk->sk_user_data == NULL)
2327 goto end;
2328
2329 /* Get the session context */
2330 err = -EBADF;
2331 session = pppol2tp_sock_to_session(sk);
2332 if (session == NULL)
2333 goto end;
2334
2335 /* Special case: if session_id == 0x0000, treat as operation on tunnel */
2336 if ((session->tunnel_addr.s_session == 0) &&
2337 (session->tunnel_addr.d_session == 0)) {
2338 err = -EBADF;
2339 tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock);
2340 if (tunnel == NULL)
2341 goto end_put_sess;
2342
2343 err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
2344 sock_put(session->tunnel_sock);
2345 } else
2346 err = pppol2tp_session_getsockopt(sk, session, optname, &val);
2347
2348 err = -EFAULT;
2349 if (put_user(len, (int __user *) optlen))
2350 goto end_put_sess;
2351
2352 if (copy_to_user((void __user *) optval, &val, len))
2353 goto end_put_sess;
2354
2355 err = 0;
2356
2357 end_put_sess:
2358 sock_put(sk);
2359 end:
2360 return err;
2361 }
2362
2363 /*****************************************************************************
2364 * /proc filesystem for debug
2365 *****************************************************************************/
2366
2367 #ifdef CONFIG_PROC_FS
2368
2369 #include <linux/seq_file.h>
2370
2371 struct pppol2tp_seq_data {
2372 struct seq_net_private p;
2373 struct pppol2tp_tunnel *tunnel; /* current tunnel */
2374 struct pppol2tp_session *session; /* NULL means get first session in tunnel */
2375 };
2376
2377 static struct pppol2tp_session *next_session(struct pppol2tp_tunnel *tunnel, struct pppol2tp_session *curr)
2378 {
2379 struct pppol2tp_session *session = NULL;
2380 struct hlist_node *walk;
2381 int found = 0;
2382 int next = 0;
2383 int i;
2384
2385 read_lock_bh(&tunnel->hlist_lock);
2386 for (i = 0; i < PPPOL2TP_HASH_SIZE; i++) {
2387 hlist_for_each_entry(session, walk, &tunnel->session_hlist[i], hlist) {
2388 if (curr == NULL) {
2389 found = 1;
2390 goto out;
2391 }
2392 if (session == curr) {
2393 next = 1;
2394 continue;
2395 }
2396 if (next) {
2397 found = 1;
2398 goto out;
2399 }
2400 }
2401 }
2402 out:
2403 read_unlock_bh(&tunnel->hlist_lock);
2404 if (!found)
2405 session = NULL;
2406
2407 return session;
2408 }
2409
2410 static struct pppol2tp_tunnel *next_tunnel(struct pppol2tp_net *pn,
2411 struct pppol2tp_tunnel *curr)
2412 {
2413 struct pppol2tp_tunnel *tunnel = NULL;
2414
2415 read_lock_bh(&pn->pppol2tp_tunnel_list_lock);
2416 if (list_is_last(&curr->list, &pn->pppol2tp_tunnel_list)) {
2417 goto out;
2418 }
2419 tunnel = list_entry(curr->list.next, struct pppol2tp_tunnel, list);
2420 out:
2421 read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
2422
2423 return tunnel;
2424 }
2425
2426 static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
2427 {
2428 struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
2429 struct pppol2tp_net *pn;
2430 loff_t pos = *offs;
2431
2432 if (!pos)
2433 goto out;
2434
2435 BUG_ON(m->private == NULL);
2436 pd = m->private;
2437 pn = pppol2tp_pernet(seq_file_net(m));
2438
2439 if (pd->tunnel == NULL) {
2440 if (!list_empty(&pn->pppol2tp_tunnel_list))
2441 pd->tunnel = list_entry(pn->pppol2tp_tunnel_list.next, struct pppol2tp_tunnel, list);
2442 } else {
2443 pd->session = next_session(pd->tunnel, pd->session);
2444 if (pd->session == NULL) {
2445 pd->tunnel = next_tunnel(pn, pd->tunnel);
2446 }
2447 }
2448
2449 /* NULL tunnel and session indicates end of list */
2450 if ((pd->tunnel == NULL) && (pd->session == NULL))
2451 pd = NULL;
2452
2453 out:
2454 return pd;
2455 }
2456
2457 static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
2458 {
2459 (*pos)++;
2460 return NULL;
2461 }
2462
2463 static void pppol2tp_seq_stop(struct seq_file *p, void *v)
2464 {
2465 /* nothing to do */
2466 }
2467
2468 static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
2469 {
2470 struct pppol2tp_tunnel *tunnel = v;
2471
2472 seq_printf(m, "\nTUNNEL '%s', %c %d\n",
2473 tunnel->name,
2474 (tunnel == tunnel->sock->sk_user_data) ? 'Y':'N',
2475 atomic_read(&tunnel->ref_count) - 1);
2476 seq_printf(m, " %08x %llu/%llu/%llu %llu/%llu/%llu\n",
2477 tunnel->debug,
2478 (unsigned long long)tunnel->stats.tx_packets,
2479 (unsigned long long)tunnel->stats.tx_bytes,
2480 (unsigned long long)tunnel->stats.tx_errors,
2481 (unsigned long long)tunnel->stats.rx_packets,
2482 (unsigned long long)tunnel->stats.rx_bytes,
2483 (unsigned long long)tunnel->stats.rx_errors);
2484 }
2485
2486 static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
2487 {
2488 struct pppol2tp_session *session = v;
2489
2490 seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
2491 "%04X/%04X %d %c\n",
2492 session->name,
2493 ntohl(session->tunnel_addr.addr.sin_addr.s_addr),
2494 ntohs(session->tunnel_addr.addr.sin_port),
2495 session->tunnel_addr.s_tunnel,
2496 session->tunnel_addr.s_session,
2497 session->tunnel_addr.d_tunnel,
2498 session->tunnel_addr.d_session,
2499 session->sock->sk_state,
2500 (session == session->sock->sk_user_data) ?
2501 'Y' : 'N');
2502 seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n",
2503 session->mtu, session->mru,
2504 session->recv_seq ? 'R' : '-',
2505 session->send_seq ? 'S' : '-',
2506 session->lns_mode ? "LNS" : "LAC",
2507 session->debug,
2508 jiffies_to_msecs(session->reorder_timeout));
2509 seq_printf(m, " %hu/%hu %llu/%llu/%llu %llu/%llu/%llu\n",
2510 session->nr, session->ns,
2511 (unsigned long long)session->stats.tx_packets,
2512 (unsigned long long)session->stats.tx_bytes,
2513 (unsigned long long)session->stats.tx_errors,
2514 (unsigned long long)session->stats.rx_packets,
2515 (unsigned long long)session->stats.rx_bytes,
2516 (unsigned long long)session->stats.rx_errors);
2517 }
2518
2519 static int pppol2tp_seq_show(struct seq_file *m, void *v)
2520 {
2521 struct pppol2tp_seq_data *pd = v;
2522
2523 /* display header on line 1 */
2524 if (v == SEQ_START_TOKEN) {
2525 seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
2526 seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
2527 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
2528 seq_puts(m, " SESSION name, addr/port src-tid/sid "
2529 "dest-tid/sid state user-data-ok\n");
2530 seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
2531 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
2532 goto out;
2533 }
2534
2535 /* Show the tunnel or session context.
2536 */
2537 if (pd->session == NULL)
2538 pppol2tp_seq_tunnel_show(m, pd->tunnel);
2539 else
2540 pppol2tp_seq_session_show(m, pd->session);
2541
2542 out:
2543 return 0;
2544 }
2545
2546 static const struct seq_operations pppol2tp_seq_ops = {
2547 .start = pppol2tp_seq_start,
2548 .next = pppol2tp_seq_next,
2549 .stop = pppol2tp_seq_stop,
2550 .show = pppol2tp_seq_show,
2551 };
2552
2553 /* Called when our /proc file is opened. We allocate data for use when
2554 * iterating our tunnel / session contexts and store it in the private
2555 * data of the seq_file.
2556 */
2557 static int pppol2tp_proc_open(struct inode *inode, struct file *file)
2558 {
2559 return seq_open_net(inode, file, &pppol2tp_seq_ops,
2560 sizeof(struct pppol2tp_seq_data));
2561 }
2562
2563 static const struct file_operations pppol2tp_proc_fops = {
2564 .owner = THIS_MODULE,
2565 .open = pppol2tp_proc_open,
2566 .read = seq_read,
2567 .llseek = seq_lseek,
2568 .release = seq_release_net,
2569 };
2570
2571 #endif /* CONFIG_PROC_FS */
2572
2573 /*****************************************************************************
2574 * Init and cleanup
2575 *****************************************************************************/
2576
2577 static struct proto_ops pppol2tp_ops = {
2578 .family = AF_PPPOX,
2579 .owner = THIS_MODULE,
2580 .release = pppol2tp_release,
2581 .bind = sock_no_bind,
2582 .connect = pppol2tp_connect,
2583 .socketpair = sock_no_socketpair,
2584 .accept = sock_no_accept,
2585 .getname = pppol2tp_getname,
2586 .poll = datagram_poll,
2587 .listen = sock_no_listen,
2588 .shutdown = sock_no_shutdown,
2589 .setsockopt = pppol2tp_setsockopt,
2590 .getsockopt = pppol2tp_getsockopt,
2591 .sendmsg = pppol2tp_sendmsg,
2592 .recvmsg = pppol2tp_recvmsg,
2593 .mmap = sock_no_mmap,
2594 .ioctl = pppox_ioctl,
2595 };
2596
2597 static struct pppox_proto pppol2tp_proto = {
2598 .create = pppol2tp_create,
2599 .ioctl = pppol2tp_ioctl
2600 };
2601
2602 static __net_init int pppol2tp_init_net(struct net *net)
2603 {
2604 struct pppol2tp_net *pn;
2605 struct proc_dir_entry *pde;
2606 int err;
2607
2608 pn = kzalloc(sizeof(*pn), GFP_KERNEL);
2609 if (!pn)
2610 return -ENOMEM;
2611
2612 INIT_LIST_HEAD(&pn->pppol2tp_tunnel_list);
2613 rwlock_init(&pn->pppol2tp_tunnel_list_lock);
2614
2615 err = net_assign_generic(net, pppol2tp_net_id, pn);
2616 if (err)
2617 goto out;
2618
2619 pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops);
2620 #ifdef CONFIG_PROC_FS
2621 if (!pde) {
2622 err = -ENOMEM;
2623 goto out;
2624 }
2625 #endif
2626
2627 return 0;
2628
2629 out:
2630 kfree(pn);
2631 return err;
2632 }
2633
2634 static __net_exit void pppol2tp_exit_net(struct net *net)
2635 {
2636 struct pppoe_net *pn;
2637
2638 proc_net_remove(net, "pppol2tp");
2639 pn = net_generic(net, pppol2tp_net_id);
2640 /*
2641 * if someone has cached our net then
2642 * further net_generic call will return NULL
2643 */
2644 net_assign_generic(net, pppol2tp_net_id, NULL);
2645 kfree(pn);
2646 }
2647
2648 static struct pernet_operations pppol2tp_net_ops = {
2649 .init = pppol2tp_init_net,
2650 .exit = pppol2tp_exit_net,
2651 };
2652
2653 static int __init pppol2tp_init(void)
2654 {
2655 int err;
2656
2657 err = proto_register(&pppol2tp_sk_proto, 0);
2658 if (err)
2659 goto out;
2660 err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
2661 if (err)
2662 goto out_unregister_pppol2tp_proto;
2663
2664 err = register_pernet_gen_device(&pppol2tp_net_id, &pppol2tp_net_ops);
2665 if (err)
2666 goto out_unregister_pppox_proto;
2667
2668 printk(KERN_INFO "PPPoL2TP kernel driver, %s\n",
2669 PPPOL2TP_DRV_VERSION);
2670
2671 out:
2672 return err;
2673 out_unregister_pppox_proto:
2674 unregister_pppox_proto(PX_PROTO_OL2TP);
2675 out_unregister_pppol2tp_proto:
2676 proto_unregister(&pppol2tp_sk_proto);
2677 goto out;
2678 }
2679
2680 static void __exit pppol2tp_exit(void)
2681 {
2682 unregister_pppox_proto(PX_PROTO_OL2TP);
2683 proto_unregister(&pppol2tp_sk_proto);
2684 }
2685
2686 module_init(pppol2tp_init);
2687 module_exit(pppol2tp_exit);
2688
2689 MODULE_AUTHOR("Martijn van Oosterhout <kleptog@svana.org>, "
2690 "James Chapman <jchapman@katalix.com>");
2691 MODULE_DESCRIPTION("PPP over L2TP over UDP");
2692 MODULE_LICENSE("GPL");
2693 MODULE_VERSION(PPPOL2TP_DRV_VERSION);
Support for the Chinese Samsung S3C2440 based development boards