Merge branch 'picoxcell-fixes' of git://github.com/jamieiles/linux-2.6-ji into fixes
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / l2tp / l2tp_ppp.c
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: 2.0.0
8 *
9 * Authors: James Chapman (jchapman@katalix.com)
10 *
11 * Based on original work by Martijn van Oosterhout <kleptog@svana.org>
12 *
13 * License:
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21 /* This driver handles only L2TP data frames; control frames are handled by a
22 * userspace application.
23 *
24 * To send data in an L2TP session, userspace opens a PPPoL2TP socket and
25 * attaches it to a bound UDP socket with local tunnel_id / session_id and
26 * peer tunnel_id / session_id set. Data can then be sent or received using
27 * regular socket sendmsg() / recvmsg() calls. Kernel parameters of the socket
28 * can be read or modified using ioctl() or [gs]etsockopt() calls.
29 *
30 * When a PPPoL2TP socket is connected with local and peer session_id values
31 * zero, the socket is treated as a special tunnel management socket.
32 *
33 * Here's example userspace code to create a socket for sending/receiving data
34 * over an L2TP session:-
35 *
36 * struct sockaddr_pppol2tp sax;
37 * int fd;
38 * int session_fd;
39 *
40 * fd = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP);
41 *
42 * sax.sa_family = AF_PPPOX;
43 * sax.sa_protocol = PX_PROTO_OL2TP;
44 * sax.pppol2tp.fd = tunnel_fd; // bound UDP socket
45 * sax.pppol2tp.addr.sin_addr.s_addr = addr->sin_addr.s_addr;
46 * sax.pppol2tp.addr.sin_port = addr->sin_port;
47 * sax.pppol2tp.addr.sin_family = AF_INET;
48 * sax.pppol2tp.s_tunnel = tunnel_id;
49 * sax.pppol2tp.s_session = session_id;
50 * sax.pppol2tp.d_tunnel = peer_tunnel_id;
51 * sax.pppol2tp.d_session = peer_session_id;
52 *
53 * session_fd = connect(fd, (struct sockaddr *)&sax, sizeof(sax));
54 *
55 * A pppd plugin that allows PPP traffic to be carried over L2TP using
56 * this driver is available from the OpenL2TP project at
57 * http://openl2tp.sourceforge.net.
58 */
59
60 #include <linux/module.h>
61 #include <linux/string.h>
62 #include <linux/list.h>
63 #include <linux/uaccess.h>
64
65 #include <linux/kernel.h>
66 #include <linux/spinlock.h>
67 #include <linux/kthread.h>
68 #include <linux/sched.h>
69 #include <linux/slab.h>
70 #include <linux/errno.h>
71 #include <linux/jiffies.h>
72
73 #include <linux/netdevice.h>
74 #include <linux/net.h>
75 #include <linux/inetdevice.h>
76 #include <linux/skbuff.h>
77 #include <linux/init.h>
78 #include <linux/ip.h>
79 #include <linux/udp.h>
80 #include <linux/if_pppox.h>
81 #include <linux/if_pppol2tp.h>
82 #include <net/sock.h>
83 #include <linux/ppp_channel.h>
84 #include <linux/ppp_defs.h>
85 #include <linux/if_ppp.h>
86 #include <linux/file.h>
87 #include <linux/hash.h>
88 #include <linux/sort.h>
89 #include <linux/proc_fs.h>
90 #include <linux/l2tp.h>
91 #include <linux/nsproxy.h>
92 #include <net/net_namespace.h>
93 #include <net/netns/generic.h>
94 #include <net/dst.h>
95 #include <net/ip.h>
96 #include <net/udp.h>
97 #include <net/xfrm.h>
98
99 #include <asm/byteorder.h>
100 #include <linux/atomic.h>
101
102 #include "l2tp_core.h"
103
104 #define PPPOL2TP_DRV_VERSION "V2.0"
105
106 /* Space for UDP, L2TP and PPP headers */
107 #define PPPOL2TP_HEADER_OVERHEAD 40
108
109 #define PRINTK(_mask, _type, _lvl, _fmt, args...) \
110 do { \
111 if ((_mask) & (_type)) \
112 printk(_lvl "PPPOL2TP: " _fmt, ##args); \
113 } while (0)
114
115 /* Number of bytes to build transmit L2TP headers.
116 * Unfortunately the size is different depending on whether sequence numbers
117 * are enabled.
118 */
119 #define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10
120 #define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6
121
122 /* Private data of each session. This data lives at the end of struct
123 * l2tp_session, referenced via session->priv[].
124 */
125 struct pppol2tp_session {
126 int owner; /* pid that opened the socket */
127
128 struct sock *sock; /* Pointer to the session
129 * PPPoX socket */
130 struct sock *tunnel_sock; /* Pointer to the tunnel UDP
131 * socket */
132 int flags; /* accessed by PPPIOCGFLAGS.
133 * Unused. */
134 };
135
136 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb);
137
138 static const struct ppp_channel_ops pppol2tp_chan_ops = {
139 .start_xmit = pppol2tp_xmit,
140 };
141
142 static const struct proto_ops pppol2tp_ops;
143
144 /* Helpers to obtain tunnel/session contexts from sockets.
145 */
146 static inline struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk)
147 {
148 struct l2tp_session *session;
149
150 if (sk == NULL)
151 return NULL;
152
153 sock_hold(sk);
154 session = (struct l2tp_session *)(sk->sk_user_data);
155 if (session == NULL) {
156 sock_put(sk);
157 goto out;
158 }
159
160 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
161
162 out:
163 return session;
164 }
165
166 /*****************************************************************************
167 * Receive data handling
168 *****************************************************************************/
169
170 static int pppol2tp_recv_payload_hook(struct sk_buff *skb)
171 {
172 /* Skip PPP header, if present. In testing, Microsoft L2TP clients
173 * don't send the PPP header (PPP header compression enabled), but
174 * other clients can include the header. So we cope with both cases
175 * here. The PPP header is always FF03 when using L2TP.
176 *
177 * Note that skb->data[] isn't dereferenced from a u16 ptr here since
178 * the field may be unaligned.
179 */
180 if (!pskb_may_pull(skb, 2))
181 return 1;
182
183 if ((skb->data[0] == 0xff) && (skb->data[1] == 0x03))
184 skb_pull(skb, 2);
185
186 return 0;
187 }
188
189 /* Receive message. This is the recvmsg for the PPPoL2TP socket.
190 */
191 static int pppol2tp_recvmsg(struct kiocb *iocb, struct socket *sock,
192 struct msghdr *msg, size_t len,
193 int flags)
194 {
195 int err;
196 struct sk_buff *skb;
197 struct sock *sk = sock->sk;
198
199 err = -EIO;
200 if (sk->sk_state & PPPOX_BOUND)
201 goto end;
202
203 msg->msg_namelen = 0;
204
205 err = 0;
206 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
207 flags & MSG_DONTWAIT, &err);
208 if (!skb)
209 goto end;
210
211 if (len > skb->len)
212 len = skb->len;
213 else if (len < skb->len)
214 msg->msg_flags |= MSG_TRUNC;
215
216 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
217 if (likely(err == 0))
218 err = len;
219
220 kfree_skb(skb);
221 end:
222 return err;
223 }
224
225 static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
226 {
227 struct pppol2tp_session *ps = l2tp_session_priv(session);
228 struct sock *sk = NULL;
229
230 /* If the socket is bound, send it in to PPP's input queue. Otherwise
231 * queue it on the session socket.
232 */
233 sk = ps->sock;
234 if (sk == NULL)
235 goto no_sock;
236
237 if (sk->sk_state & PPPOX_BOUND) {
238 struct pppox_sock *po;
239 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG,
240 "%s: recv %d byte data frame, passing to ppp\n",
241 session->name, data_len);
242
243 /* We need to forget all info related to the L2TP packet
244 * gathered in the skb as we are going to reuse the same
245 * skb for the inner packet.
246 * Namely we need to:
247 * - reset xfrm (IPSec) information as it applies to
248 * the outer L2TP packet and not to the inner one
249 * - release the dst to force a route lookup on the inner
250 * IP packet since skb->dst currently points to the dst
251 * of the UDP tunnel
252 * - reset netfilter information as it doesn't apply
253 * to the inner packet either
254 */
255 secpath_reset(skb);
256 skb_dst_drop(skb);
257 nf_reset(skb);
258
259 po = pppox_sk(sk);
260 ppp_input(&po->chan, skb);
261 } else {
262 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_INFO,
263 "%s: socket not bound\n", session->name);
264
265 /* Not bound. Nothing we can do, so discard. */
266 session->stats.rx_errors++;
267 kfree_skb(skb);
268 }
269
270 return;
271
272 no_sock:
273 PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_INFO,
274 "%s: no socket\n", session->name);
275 kfree_skb(skb);
276 }
277
278 static void pppol2tp_session_sock_hold(struct l2tp_session *session)
279 {
280 struct pppol2tp_session *ps = l2tp_session_priv(session);
281
282 if (ps->sock)
283 sock_hold(ps->sock);
284 }
285
286 static void pppol2tp_session_sock_put(struct l2tp_session *session)
287 {
288 struct pppol2tp_session *ps = l2tp_session_priv(session);
289
290 if (ps->sock)
291 sock_put(ps->sock);
292 }
293
294 /************************************************************************
295 * Transmit handling
296 ***********************************************************************/
297
298 /* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
299 * when a user application does a sendmsg() on the session socket. L2TP and
300 * PPP headers must be inserted into the user's data.
301 */
302 static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
303 size_t total_len)
304 {
305 static const unsigned char ppph[2] = { 0xff, 0x03 };
306 struct sock *sk = sock->sk;
307 struct sk_buff *skb;
308 int error;
309 struct l2tp_session *session;
310 struct l2tp_tunnel *tunnel;
311 struct pppol2tp_session *ps;
312 int uhlen;
313
314 error = -ENOTCONN;
315 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
316 goto error;
317
318 /* Get session and tunnel contexts */
319 error = -EBADF;
320 session = pppol2tp_sock_to_session(sk);
321 if (session == NULL)
322 goto error;
323
324 ps = l2tp_session_priv(session);
325 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
326 if (tunnel == NULL)
327 goto error_put_sess;
328
329 uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
330
331 /* Allocate a socket buffer */
332 error = -ENOMEM;
333 skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) +
334 uhlen + session->hdr_len +
335 sizeof(ppph) + total_len,
336 0, GFP_KERNEL);
337 if (!skb)
338 goto error_put_sess_tun;
339
340 /* Reserve space for headers. */
341 skb_reserve(skb, NET_SKB_PAD);
342 skb_reset_network_header(skb);
343 skb_reserve(skb, sizeof(struct iphdr));
344 skb_reset_transport_header(skb);
345 skb_reserve(skb, uhlen);
346
347 /* Add PPP header */
348 skb->data[0] = ppph[0];
349 skb->data[1] = ppph[1];
350 skb_put(skb, 2);
351
352 /* Copy user data into skb */
353 error = memcpy_fromiovec(skb->data, m->msg_iov, total_len);
354 if (error < 0) {
355 kfree_skb(skb);
356 goto error_put_sess_tun;
357 }
358 skb_put(skb, total_len);
359
360 l2tp_xmit_skb(session, skb, session->hdr_len);
361
362 sock_put(ps->tunnel_sock);
363
364 return error;
365
366 error_put_sess_tun:
367 sock_put(ps->tunnel_sock);
368 error_put_sess:
369 sock_put(sk);
370 error:
371 return error;
372 }
373
374 /* Transmit function called by generic PPP driver. Sends PPP frame
375 * over PPPoL2TP socket.
376 *
377 * This is almost the same as pppol2tp_sendmsg(), but rather than
378 * being called with a msghdr from userspace, it is called with a skb
379 * from the kernel.
380 *
381 * The supplied skb from ppp doesn't have enough headroom for the
382 * insertion of L2TP, UDP and IP headers so we need to allocate more
383 * headroom in the skb. This will create a cloned skb. But we must be
384 * careful in the error case because the caller will expect to free
385 * the skb it supplied, not our cloned skb. So we take care to always
386 * leave the original skb unfreed if we return an error.
387 */
388 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
389 {
390 static const u8 ppph[2] = { 0xff, 0x03 };
391 struct sock *sk = (struct sock *) chan->private;
392 struct sock *sk_tun;
393 struct l2tp_session *session;
394 struct l2tp_tunnel *tunnel;
395 struct pppol2tp_session *ps;
396 int old_headroom;
397 int new_headroom;
398 int uhlen, headroom;
399
400 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
401 goto abort;
402
403 /* Get session and tunnel contexts from the socket */
404 session = pppol2tp_sock_to_session(sk);
405 if (session == NULL)
406 goto abort;
407
408 ps = l2tp_session_priv(session);
409 sk_tun = ps->tunnel_sock;
410 if (sk_tun == NULL)
411 goto abort_put_sess;
412 tunnel = l2tp_sock_to_tunnel(sk_tun);
413 if (tunnel == NULL)
414 goto abort_put_sess;
415
416 old_headroom = skb_headroom(skb);
417 uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
418 headroom = NET_SKB_PAD +
419 sizeof(struct iphdr) + /* IP header */
420 uhlen + /* UDP header (if L2TP_ENCAPTYPE_UDP) */
421 session->hdr_len + /* L2TP header */
422 sizeof(ppph); /* PPP header */
423 if (skb_cow_head(skb, headroom))
424 goto abort_put_sess_tun;
425
426 new_headroom = skb_headroom(skb);
427 skb->truesize += new_headroom - old_headroom;
428
429 /* Setup PPP header */
430 __skb_push(skb, sizeof(ppph));
431 skb->data[0] = ppph[0];
432 skb->data[1] = ppph[1];
433
434 l2tp_xmit_skb(session, skb, session->hdr_len);
435
436 sock_put(sk_tun);
437 sock_put(sk);
438 return 1;
439
440 abort_put_sess_tun:
441 sock_put(sk_tun);
442 abort_put_sess:
443 sock_put(sk);
444 abort:
445 /* Free the original skb */
446 kfree_skb(skb);
447 return 1;
448 }
449
450 /*****************************************************************************
451 * Session (and tunnel control) socket create/destroy.
452 *****************************************************************************/
453
454 /* Called by l2tp_core when a session socket is being closed.
455 */
456 static void pppol2tp_session_close(struct l2tp_session *session)
457 {
458 struct pppol2tp_session *ps = l2tp_session_priv(session);
459 struct sock *sk = ps->sock;
460 struct sk_buff *skb;
461
462 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
463
464 if (session->session_id == 0)
465 goto out;
466
467 if (sk != NULL) {
468 lock_sock(sk);
469
470 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
471 pppox_unbind_sock(sk);
472 sk->sk_state = PPPOX_DEAD;
473 sk->sk_state_change(sk);
474 }
475
476 /* Purge any queued data */
477 skb_queue_purge(&sk->sk_receive_queue);
478 skb_queue_purge(&sk->sk_write_queue);
479 while ((skb = skb_dequeue(&session->reorder_q))) {
480 kfree_skb(skb);
481 sock_put(sk);
482 }
483
484 release_sock(sk);
485 }
486
487 out:
488 return;
489 }
490
491 /* Really kill the session socket. (Called from sock_put() if
492 * refcnt == 0.)
493 */
494 static void pppol2tp_session_destruct(struct sock *sk)
495 {
496 struct l2tp_session *session;
497
498 if (sk->sk_user_data != NULL) {
499 session = sk->sk_user_data;
500 if (session == NULL)
501 goto out;
502
503 sk->sk_user_data = NULL;
504 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
505 l2tp_session_dec_refcount(session);
506 }
507
508 out:
509 return;
510 }
511
512 /* Called when the PPPoX socket (session) is closed.
513 */
514 static int pppol2tp_release(struct socket *sock)
515 {
516 struct sock *sk = sock->sk;
517 struct l2tp_session *session;
518 int error;
519
520 if (!sk)
521 return 0;
522
523 error = -EBADF;
524 lock_sock(sk);
525 if (sock_flag(sk, SOCK_DEAD) != 0)
526 goto error;
527
528 pppox_unbind_sock(sk);
529
530 /* Signal the death of the socket. */
531 sk->sk_state = PPPOX_DEAD;
532 sock_orphan(sk);
533 sock->sk = NULL;
534
535 session = pppol2tp_sock_to_session(sk);
536
537 /* Purge any queued data */
538 skb_queue_purge(&sk->sk_receive_queue);
539 skb_queue_purge(&sk->sk_write_queue);
540 if (session != NULL) {
541 struct sk_buff *skb;
542 while ((skb = skb_dequeue(&session->reorder_q))) {
543 kfree_skb(skb);
544 sock_put(sk);
545 }
546 sock_put(sk);
547 }
548
549 release_sock(sk);
550
551 /* This will delete the session context via
552 * pppol2tp_session_destruct() if the socket's refcnt drops to
553 * zero.
554 */
555 sock_put(sk);
556
557 return 0;
558
559 error:
560 release_sock(sk);
561 return error;
562 }
563
564 static struct proto pppol2tp_sk_proto = {
565 .name = "PPPOL2TP",
566 .owner = THIS_MODULE,
567 .obj_size = sizeof(struct pppox_sock),
568 };
569
570 static int pppol2tp_backlog_recv(struct sock *sk, struct sk_buff *skb)
571 {
572 int rc;
573
574 rc = l2tp_udp_encap_recv(sk, skb);
575 if (rc)
576 kfree_skb(skb);
577
578 return NET_RX_SUCCESS;
579 }
580
581 /* socket() handler. Initialize a new struct sock.
582 */
583 static int pppol2tp_create(struct net *net, struct socket *sock)
584 {
585 int error = -ENOMEM;
586 struct sock *sk;
587
588 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto);
589 if (!sk)
590 goto out;
591
592 sock_init_data(sock, sk);
593
594 sock->state = SS_UNCONNECTED;
595 sock->ops = &pppol2tp_ops;
596
597 sk->sk_backlog_rcv = pppol2tp_backlog_recv;
598 sk->sk_protocol = PX_PROTO_OL2TP;
599 sk->sk_family = PF_PPPOX;
600 sk->sk_state = PPPOX_NONE;
601 sk->sk_type = SOCK_STREAM;
602 sk->sk_destruct = pppol2tp_session_destruct;
603
604 error = 0;
605
606 out:
607 return error;
608 }
609
610 #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
611 static void pppol2tp_show(struct seq_file *m, void *arg)
612 {
613 struct l2tp_session *session = arg;
614 struct pppol2tp_session *ps = l2tp_session_priv(session);
615
616 if (ps) {
617 struct pppox_sock *po = pppox_sk(ps->sock);
618 if (po)
619 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
620 }
621 }
622 #endif
623
624 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
625 */
626 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
627 int sockaddr_len, int flags)
628 {
629 struct sock *sk = sock->sk;
630 struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
631 struct sockaddr_pppol2tpv3 *sp3 = (struct sockaddr_pppol2tpv3 *) uservaddr;
632 struct pppox_sock *po = pppox_sk(sk);
633 struct l2tp_session *session = NULL;
634 struct l2tp_tunnel *tunnel;
635 struct pppol2tp_session *ps;
636 struct dst_entry *dst;
637 struct l2tp_session_cfg cfg = { 0, };
638 int error = 0;
639 u32 tunnel_id, peer_tunnel_id;
640 u32 session_id, peer_session_id;
641 int ver = 2;
642 int fd;
643
644 lock_sock(sk);
645
646 error = -EINVAL;
647 if (sp->sa_protocol != PX_PROTO_OL2TP)
648 goto end;
649
650 /* Check for already bound sockets */
651 error = -EBUSY;
652 if (sk->sk_state & PPPOX_CONNECTED)
653 goto end;
654
655 /* We don't supporting rebinding anyway */
656 error = -EALREADY;
657 if (sk->sk_user_data)
658 goto end; /* socket is already attached */
659
660 /* Get params from socket address. Handle L2TPv2 and L2TPv3 */
661 if (sockaddr_len == sizeof(struct sockaddr_pppol2tp)) {
662 fd = sp->pppol2tp.fd;
663 tunnel_id = sp->pppol2tp.s_tunnel;
664 peer_tunnel_id = sp->pppol2tp.d_tunnel;
665 session_id = sp->pppol2tp.s_session;
666 peer_session_id = sp->pppol2tp.d_session;
667 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3)) {
668 ver = 3;
669 fd = sp3->pppol2tp.fd;
670 tunnel_id = sp3->pppol2tp.s_tunnel;
671 peer_tunnel_id = sp3->pppol2tp.d_tunnel;
672 session_id = sp3->pppol2tp.s_session;
673 peer_session_id = sp3->pppol2tp.d_session;
674 } else {
675 error = -EINVAL;
676 goto end; /* bad socket address */
677 }
678
679 /* Don't bind if tunnel_id is 0 */
680 error = -EINVAL;
681 if (tunnel_id == 0)
682 goto end;
683
684 tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id);
685
686 /* Special case: create tunnel context if session_id and
687 * peer_session_id is 0. Otherwise look up tunnel using supplied
688 * tunnel id.
689 */
690 if ((session_id == 0) && (peer_session_id == 0)) {
691 if (tunnel == NULL) {
692 struct l2tp_tunnel_cfg tcfg = {
693 .encap = L2TP_ENCAPTYPE_UDP,
694 .debug = 0,
695 };
696 error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, &tcfg, &tunnel);
697 if (error < 0)
698 goto end;
699 }
700 } else {
701 /* Error if we can't find the tunnel */
702 error = -ENOENT;
703 if (tunnel == NULL)
704 goto end;
705
706 /* Error if socket is not prepped */
707 if (tunnel->sock == NULL)
708 goto end;
709 }
710
711 if (tunnel->recv_payload_hook == NULL)
712 tunnel->recv_payload_hook = pppol2tp_recv_payload_hook;
713
714 if (tunnel->peer_tunnel_id == 0) {
715 if (ver == 2)
716 tunnel->peer_tunnel_id = sp->pppol2tp.d_tunnel;
717 else
718 tunnel->peer_tunnel_id = sp3->pppol2tp.d_tunnel;
719 }
720
721 /* Create session if it doesn't already exist. We handle the
722 * case where a session was previously created by the netlink
723 * interface by checking that the session doesn't already have
724 * a socket and its tunnel socket are what we expect. If any
725 * of those checks fail, return EEXIST to the caller.
726 */
727 session = l2tp_session_find(sock_net(sk), tunnel, session_id);
728 if (session == NULL) {
729 /* Default MTU must allow space for UDP/L2TP/PPP
730 * headers.
731 */
732 cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
733
734 /* Allocate and initialize a new session context. */
735 session = l2tp_session_create(sizeof(struct pppol2tp_session),
736 tunnel, session_id,
737 peer_session_id, &cfg);
738 if (session == NULL) {
739 error = -ENOMEM;
740 goto end;
741 }
742 } else {
743 ps = l2tp_session_priv(session);
744 error = -EEXIST;
745 if (ps->sock != NULL)
746 goto end;
747
748 /* consistency checks */
749 if (ps->tunnel_sock != tunnel->sock)
750 goto end;
751 }
752
753 /* Associate session with its PPPoL2TP socket */
754 ps = l2tp_session_priv(session);
755 ps->owner = current->pid;
756 ps->sock = sk;
757 ps->tunnel_sock = tunnel->sock;
758
759 session->recv_skb = pppol2tp_recv;
760 session->session_close = pppol2tp_session_close;
761 #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
762 session->show = pppol2tp_show;
763 #endif
764
765 /* We need to know each time a skb is dropped from the reorder
766 * queue.
767 */
768 session->ref = pppol2tp_session_sock_hold;
769 session->deref = pppol2tp_session_sock_put;
770
771 /* If PMTU discovery was enabled, use the MTU that was discovered */
772 dst = sk_dst_get(sk);
773 if (dst != NULL) {
774 u32 pmtu = dst_mtu(__sk_dst_get(sk));
775 if (pmtu != 0)
776 session->mtu = session->mru = pmtu -
777 PPPOL2TP_HEADER_OVERHEAD;
778 dst_release(dst);
779 }
780
781 /* Special case: if source & dest session_id == 0x0000, this
782 * socket is being created to manage the tunnel. Just set up
783 * the internal context for use by ioctl() and sockopt()
784 * handlers.
785 */
786 if ((session->session_id == 0) &&
787 (session->peer_session_id == 0)) {
788 error = 0;
789 goto out_no_ppp;
790 }
791
792 /* The only header we need to worry about is the L2TP
793 * header. This size is different depending on whether
794 * sequence numbers are enabled for the data channel.
795 */
796 po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
797
798 po->chan.private = sk;
799 po->chan.ops = &pppol2tp_chan_ops;
800 po->chan.mtu = session->mtu;
801
802 error = ppp_register_net_channel(sock_net(sk), &po->chan);
803 if (error)
804 goto end;
805
806 out_no_ppp:
807 /* This is how we get the session context from the socket. */
808 sk->sk_user_data = session;
809 sk->sk_state = PPPOX_CONNECTED;
810 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
811 "%s: created\n", session->name);
812
813 end:
814 release_sock(sk);
815
816 return error;
817 }
818
819 #ifdef CONFIG_L2TP_V3
820
821 /* Called when creating sessions via the netlink interface.
822 */
823 static int pppol2tp_session_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
824 {
825 int error;
826 struct l2tp_tunnel *tunnel;
827 struct l2tp_session *session;
828 struct pppol2tp_session *ps;
829
830 tunnel = l2tp_tunnel_find(net, tunnel_id);
831
832 /* Error if we can't find the tunnel */
833 error = -ENOENT;
834 if (tunnel == NULL)
835 goto out;
836
837 /* Error if tunnel socket is not prepped */
838 if (tunnel->sock == NULL)
839 goto out;
840
841 /* Check that this session doesn't already exist */
842 error = -EEXIST;
843 session = l2tp_session_find(net, tunnel, session_id);
844 if (session != NULL)
845 goto out;
846
847 /* Default MTU values. */
848 if (cfg->mtu == 0)
849 cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
850 if (cfg->mru == 0)
851 cfg->mru = cfg->mtu;
852
853 /* Allocate and initialize a new session context. */
854 error = -ENOMEM;
855 session = l2tp_session_create(sizeof(struct pppol2tp_session),
856 tunnel, session_id,
857 peer_session_id, cfg);
858 if (session == NULL)
859 goto out;
860
861 ps = l2tp_session_priv(session);
862 ps->tunnel_sock = tunnel->sock;
863
864 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
865 "%s: created\n", session->name);
866
867 error = 0;
868
869 out:
870 return error;
871 }
872
873 /* Called when deleting sessions via the netlink interface.
874 */
875 static int pppol2tp_session_delete(struct l2tp_session *session)
876 {
877 struct pppol2tp_session *ps = l2tp_session_priv(session);
878
879 if (ps->sock == NULL)
880 l2tp_session_dec_refcount(session);
881
882 return 0;
883 }
884
885 #endif /* CONFIG_L2TP_V3 */
886
887 /* getname() support.
888 */
889 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
890 int *usockaddr_len, int peer)
891 {
892 int len = 0;
893 int error = 0;
894 struct l2tp_session *session;
895 struct l2tp_tunnel *tunnel;
896 struct sock *sk = sock->sk;
897 struct inet_sock *inet;
898 struct pppol2tp_session *pls;
899
900 error = -ENOTCONN;
901 if (sk == NULL)
902 goto end;
903 if (sk->sk_state != PPPOX_CONNECTED)
904 goto end;
905
906 error = -EBADF;
907 session = pppol2tp_sock_to_session(sk);
908 if (session == NULL)
909 goto end;
910
911 pls = l2tp_session_priv(session);
912 tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock);
913 if (tunnel == NULL) {
914 error = -EBADF;
915 goto end_put_sess;
916 }
917
918 inet = inet_sk(sk);
919 if (tunnel->version == 2) {
920 struct sockaddr_pppol2tp sp;
921 len = sizeof(sp);
922 memset(&sp, 0, len);
923 sp.sa_family = AF_PPPOX;
924 sp.sa_protocol = PX_PROTO_OL2TP;
925 sp.pppol2tp.fd = tunnel->fd;
926 sp.pppol2tp.pid = pls->owner;
927 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
928 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
929 sp.pppol2tp.s_session = session->session_id;
930 sp.pppol2tp.d_session = session->peer_session_id;
931 sp.pppol2tp.addr.sin_family = AF_INET;
932 sp.pppol2tp.addr.sin_port = inet->inet_dport;
933 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
934 memcpy(uaddr, &sp, len);
935 } else if (tunnel->version == 3) {
936 struct sockaddr_pppol2tpv3 sp;
937 len = sizeof(sp);
938 memset(&sp, 0, len);
939 sp.sa_family = AF_PPPOX;
940 sp.sa_protocol = PX_PROTO_OL2TP;
941 sp.pppol2tp.fd = tunnel->fd;
942 sp.pppol2tp.pid = pls->owner;
943 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
944 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
945 sp.pppol2tp.s_session = session->session_id;
946 sp.pppol2tp.d_session = session->peer_session_id;
947 sp.pppol2tp.addr.sin_family = AF_INET;
948 sp.pppol2tp.addr.sin_port = inet->inet_dport;
949 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
950 memcpy(uaddr, &sp, len);
951 }
952
953 *usockaddr_len = len;
954
955 sock_put(pls->tunnel_sock);
956 end_put_sess:
957 sock_put(sk);
958 error = 0;
959
960 end:
961 return error;
962 }
963
964 /****************************************************************************
965 * ioctl() handlers.
966 *
967 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
968 * sockets. However, in order to control kernel tunnel features, we allow
969 * userspace to create a special "tunnel" PPPoX socket which is used for
970 * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
971 * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
972 * calls.
973 ****************************************************************************/
974
975 static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest,
976 struct l2tp_stats *stats)
977 {
978 dest->tx_packets = stats->tx_packets;
979 dest->tx_bytes = stats->tx_bytes;
980 dest->tx_errors = stats->tx_errors;
981 dest->rx_packets = stats->rx_packets;
982 dest->rx_bytes = stats->rx_bytes;
983 dest->rx_seq_discards = stats->rx_seq_discards;
984 dest->rx_oos_packets = stats->rx_oos_packets;
985 dest->rx_errors = stats->rx_errors;
986 }
987
988 /* Session ioctl helper.
989 */
990 static int pppol2tp_session_ioctl(struct l2tp_session *session,
991 unsigned int cmd, unsigned long arg)
992 {
993 struct ifreq ifr;
994 int err = 0;
995 struct sock *sk;
996 int val = (int) arg;
997 struct pppol2tp_session *ps = l2tp_session_priv(session);
998 struct l2tp_tunnel *tunnel = session->tunnel;
999 struct pppol2tp_ioc_stats stats;
1000
1001 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1002 "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n",
1003 session->name, cmd, arg);
1004
1005 sk = ps->sock;
1006 sock_hold(sk);
1007
1008 switch (cmd) {
1009 case SIOCGIFMTU:
1010 err = -ENXIO;
1011 if (!(sk->sk_state & PPPOX_CONNECTED))
1012 break;
1013
1014 err = -EFAULT;
1015 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1016 break;
1017 ifr.ifr_mtu = session->mtu;
1018 if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq)))
1019 break;
1020
1021 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1022 "%s: get mtu=%d\n", session->name, session->mtu);
1023 err = 0;
1024 break;
1025
1026 case SIOCSIFMTU:
1027 err = -ENXIO;
1028 if (!(sk->sk_state & PPPOX_CONNECTED))
1029 break;
1030
1031 err = -EFAULT;
1032 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1033 break;
1034
1035 session->mtu = ifr.ifr_mtu;
1036
1037 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1038 "%s: set mtu=%d\n", session->name, session->mtu);
1039 err = 0;
1040 break;
1041
1042 case PPPIOCGMRU:
1043 err = -ENXIO;
1044 if (!(sk->sk_state & PPPOX_CONNECTED))
1045 break;
1046
1047 err = -EFAULT;
1048 if (put_user(session->mru, (int __user *) arg))
1049 break;
1050
1051 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1052 "%s: get mru=%d\n", session->name, session->mru);
1053 err = 0;
1054 break;
1055
1056 case PPPIOCSMRU:
1057 err = -ENXIO;
1058 if (!(sk->sk_state & PPPOX_CONNECTED))
1059 break;
1060
1061 err = -EFAULT;
1062 if (get_user(val, (int __user *) arg))
1063 break;
1064
1065 session->mru = val;
1066 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1067 "%s: set mru=%d\n", session->name, session->mru);
1068 err = 0;
1069 break;
1070
1071 case PPPIOCGFLAGS:
1072 err = -EFAULT;
1073 if (put_user(ps->flags, (int __user *) arg))
1074 break;
1075
1076 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1077 "%s: get flags=%d\n", session->name, ps->flags);
1078 err = 0;
1079 break;
1080
1081 case PPPIOCSFLAGS:
1082 err = -EFAULT;
1083 if (get_user(val, (int __user *) arg))
1084 break;
1085 ps->flags = val;
1086 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1087 "%s: set flags=%d\n", session->name, ps->flags);
1088 err = 0;
1089 break;
1090
1091 case PPPIOCGL2TPSTATS:
1092 err = -ENXIO;
1093 if (!(sk->sk_state & PPPOX_CONNECTED))
1094 break;
1095
1096 memset(&stats, 0, sizeof(stats));
1097 stats.tunnel_id = tunnel->tunnel_id;
1098 stats.session_id = session->session_id;
1099 pppol2tp_copy_stats(&stats, &session->stats);
1100 if (copy_to_user((void __user *) arg, &stats,
1101 sizeof(stats)))
1102 break;
1103 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1104 "%s: get L2TP stats\n", session->name);
1105 err = 0;
1106 break;
1107
1108 default:
1109 err = -ENOSYS;
1110 break;
1111 }
1112
1113 sock_put(sk);
1114
1115 return err;
1116 }
1117
1118 /* Tunnel ioctl helper.
1119 *
1120 * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data
1121 * specifies a session_id, the session ioctl handler is called. This allows an
1122 * application to retrieve session stats via a tunnel socket.
1123 */
1124 static int pppol2tp_tunnel_ioctl(struct l2tp_tunnel *tunnel,
1125 unsigned int cmd, unsigned long arg)
1126 {
1127 int err = 0;
1128 struct sock *sk;
1129 struct pppol2tp_ioc_stats stats;
1130
1131 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1132 "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n",
1133 tunnel->name, cmd, arg);
1134
1135 sk = tunnel->sock;
1136 sock_hold(sk);
1137
1138 switch (cmd) {
1139 case PPPIOCGL2TPSTATS:
1140 err = -ENXIO;
1141 if (!(sk->sk_state & PPPOX_CONNECTED))
1142 break;
1143
1144 if (copy_from_user(&stats, (void __user *) arg,
1145 sizeof(stats))) {
1146 err = -EFAULT;
1147 break;
1148 }
1149 if (stats.session_id != 0) {
1150 /* resend to session ioctl handler */
1151 struct l2tp_session *session =
1152 l2tp_session_find(sock_net(sk), tunnel, stats.session_id);
1153 if (session != NULL)
1154 err = pppol2tp_session_ioctl(session, cmd, arg);
1155 else
1156 err = -EBADR;
1157 break;
1158 }
1159 #ifdef CONFIG_XFRM
1160 stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0;
1161 #endif
1162 pppol2tp_copy_stats(&stats, &tunnel->stats);
1163 if (copy_to_user((void __user *) arg, &stats, sizeof(stats))) {
1164 err = -EFAULT;
1165 break;
1166 }
1167 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1168 "%s: get L2TP stats\n", tunnel->name);
1169 err = 0;
1170 break;
1171
1172 default:
1173 err = -ENOSYS;
1174 break;
1175 }
1176
1177 sock_put(sk);
1178
1179 return err;
1180 }
1181
1182 /* Main ioctl() handler.
1183 * Dispatch to tunnel or session helpers depending on the socket.
1184 */
1185 static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
1186 unsigned long arg)
1187 {
1188 struct sock *sk = sock->sk;
1189 struct l2tp_session *session;
1190 struct l2tp_tunnel *tunnel;
1191 struct pppol2tp_session *ps;
1192 int err;
1193
1194 if (!sk)
1195 return 0;
1196
1197 err = -EBADF;
1198 if (sock_flag(sk, SOCK_DEAD) != 0)
1199 goto end;
1200
1201 err = -ENOTCONN;
1202 if ((sk->sk_user_data == NULL) ||
1203 (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND))))
1204 goto end;
1205
1206 /* Get session context from the socket */
1207 err = -EBADF;
1208 session = pppol2tp_sock_to_session(sk);
1209 if (session == NULL)
1210 goto end;
1211
1212 /* Special case: if session's session_id is zero, treat ioctl as a
1213 * tunnel ioctl
1214 */
1215 ps = l2tp_session_priv(session);
1216 if ((session->session_id == 0) &&
1217 (session->peer_session_id == 0)) {
1218 err = -EBADF;
1219 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1220 if (tunnel == NULL)
1221 goto end_put_sess;
1222
1223 err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
1224 sock_put(ps->tunnel_sock);
1225 goto end_put_sess;
1226 }
1227
1228 err = pppol2tp_session_ioctl(session, cmd, arg);
1229
1230 end_put_sess:
1231 sock_put(sk);
1232 end:
1233 return err;
1234 }
1235
1236 /*****************************************************************************
1237 * setsockopt() / getsockopt() support.
1238 *
1239 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1240 * sockets. In order to control kernel tunnel features, we allow userspace to
1241 * create a special "tunnel" PPPoX socket which is used for control only.
1242 * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
1243 * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
1244 *****************************************************************************/
1245
1246 /* Tunnel setsockopt() helper.
1247 */
1248 static int pppol2tp_tunnel_setsockopt(struct sock *sk,
1249 struct l2tp_tunnel *tunnel,
1250 int optname, int val)
1251 {
1252 int err = 0;
1253
1254 switch (optname) {
1255 case PPPOL2TP_SO_DEBUG:
1256 tunnel->debug = val;
1257 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1258 "%s: set debug=%x\n", tunnel->name, tunnel->debug);
1259 break;
1260
1261 default:
1262 err = -ENOPROTOOPT;
1263 break;
1264 }
1265
1266 return err;
1267 }
1268
1269 /* Session setsockopt helper.
1270 */
1271 static int pppol2tp_session_setsockopt(struct sock *sk,
1272 struct l2tp_session *session,
1273 int optname, int val)
1274 {
1275 int err = 0;
1276 struct pppol2tp_session *ps = l2tp_session_priv(session);
1277
1278 switch (optname) {
1279 case PPPOL2TP_SO_RECVSEQ:
1280 if ((val != 0) && (val != 1)) {
1281 err = -EINVAL;
1282 break;
1283 }
1284 session->recv_seq = val ? -1 : 0;
1285 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1286 "%s: set recv_seq=%d\n", session->name, session->recv_seq);
1287 break;
1288
1289 case PPPOL2TP_SO_SENDSEQ:
1290 if ((val != 0) && (val != 1)) {
1291 err = -EINVAL;
1292 break;
1293 }
1294 session->send_seq = val ? -1 : 0;
1295 {
1296 struct sock *ssk = ps->sock;
1297 struct pppox_sock *po = pppox_sk(ssk);
1298 po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
1299 PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
1300 }
1301 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1302 "%s: set send_seq=%d\n", session->name, session->send_seq);
1303 break;
1304
1305 case PPPOL2TP_SO_LNSMODE:
1306 if ((val != 0) && (val != 1)) {
1307 err = -EINVAL;
1308 break;
1309 }
1310 session->lns_mode = val ? -1 : 0;
1311 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1312 "%s: set lns_mode=%d\n", session->name, session->lns_mode);
1313 break;
1314
1315 case PPPOL2TP_SO_DEBUG:
1316 session->debug = val;
1317 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1318 "%s: set debug=%x\n", session->name, session->debug);
1319 break;
1320
1321 case PPPOL2TP_SO_REORDERTO:
1322 session->reorder_timeout = msecs_to_jiffies(val);
1323 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1324 "%s: set reorder_timeout=%d\n", session->name, session->reorder_timeout);
1325 break;
1326
1327 default:
1328 err = -ENOPROTOOPT;
1329 break;
1330 }
1331
1332 return err;
1333 }
1334
1335 /* Main setsockopt() entry point.
1336 * Does API checks, then calls either the tunnel or session setsockopt
1337 * handler, according to whether the PPPoL2TP socket is a for a regular
1338 * session or the special tunnel type.
1339 */
1340 static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
1341 char __user *optval, unsigned int optlen)
1342 {
1343 struct sock *sk = sock->sk;
1344 struct l2tp_session *session;
1345 struct l2tp_tunnel *tunnel;
1346 struct pppol2tp_session *ps;
1347 int val;
1348 int err;
1349
1350 if (level != SOL_PPPOL2TP)
1351 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1352
1353 if (optlen < sizeof(int))
1354 return -EINVAL;
1355
1356 if (get_user(val, (int __user *)optval))
1357 return -EFAULT;
1358
1359 err = -ENOTCONN;
1360 if (sk->sk_user_data == NULL)
1361 goto end;
1362
1363 /* Get session context from the socket */
1364 err = -EBADF;
1365 session = pppol2tp_sock_to_session(sk);
1366 if (session == NULL)
1367 goto end;
1368
1369 /* Special case: if session_id == 0x0000, treat as operation on tunnel
1370 */
1371 ps = l2tp_session_priv(session);
1372 if ((session->session_id == 0) &&
1373 (session->peer_session_id == 0)) {
1374 err = -EBADF;
1375 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1376 if (tunnel == NULL)
1377 goto end_put_sess;
1378
1379 err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
1380 sock_put(ps->tunnel_sock);
1381 } else
1382 err = pppol2tp_session_setsockopt(sk, session, optname, val);
1383
1384 err = 0;
1385
1386 end_put_sess:
1387 sock_put(sk);
1388 end:
1389 return err;
1390 }
1391
1392 /* Tunnel getsockopt helper. Called with sock locked.
1393 */
1394 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
1395 struct l2tp_tunnel *tunnel,
1396 int optname, int *val)
1397 {
1398 int err = 0;
1399
1400 switch (optname) {
1401 case PPPOL2TP_SO_DEBUG:
1402 *val = tunnel->debug;
1403 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1404 "%s: get debug=%x\n", tunnel->name, tunnel->debug);
1405 break;
1406
1407 default:
1408 err = -ENOPROTOOPT;
1409 break;
1410 }
1411
1412 return err;
1413 }
1414
1415 /* Session getsockopt helper. Called with sock locked.
1416 */
1417 static int pppol2tp_session_getsockopt(struct sock *sk,
1418 struct l2tp_session *session,
1419 int optname, int *val)
1420 {
1421 int err = 0;
1422
1423 switch (optname) {
1424 case PPPOL2TP_SO_RECVSEQ:
1425 *val = session->recv_seq;
1426 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1427 "%s: get recv_seq=%d\n", session->name, *val);
1428 break;
1429
1430 case PPPOL2TP_SO_SENDSEQ:
1431 *val = session->send_seq;
1432 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1433 "%s: get send_seq=%d\n", session->name, *val);
1434 break;
1435
1436 case PPPOL2TP_SO_LNSMODE:
1437 *val = session->lns_mode;
1438 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1439 "%s: get lns_mode=%d\n", session->name, *val);
1440 break;
1441
1442 case PPPOL2TP_SO_DEBUG:
1443 *val = session->debug;
1444 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1445 "%s: get debug=%d\n", session->name, *val);
1446 break;
1447
1448 case PPPOL2TP_SO_REORDERTO:
1449 *val = (int) jiffies_to_msecs(session->reorder_timeout);
1450 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1451 "%s: get reorder_timeout=%d\n", session->name, *val);
1452 break;
1453
1454 default:
1455 err = -ENOPROTOOPT;
1456 }
1457
1458 return err;
1459 }
1460
1461 /* Main getsockopt() entry point.
1462 * Does API checks, then calls either the tunnel or session getsockopt
1463 * handler, according to whether the PPPoX socket is a for a regular session
1464 * or the special tunnel type.
1465 */
1466 static int pppol2tp_getsockopt(struct socket *sock, int level,
1467 int optname, char __user *optval, int __user *optlen)
1468 {
1469 struct sock *sk = sock->sk;
1470 struct l2tp_session *session;
1471 struct l2tp_tunnel *tunnel;
1472 int val, len;
1473 int err;
1474 struct pppol2tp_session *ps;
1475
1476 if (level != SOL_PPPOL2TP)
1477 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1478
1479 if (get_user(len, (int __user *) optlen))
1480 return -EFAULT;
1481
1482 len = min_t(unsigned int, len, sizeof(int));
1483
1484 if (len < 0)
1485 return -EINVAL;
1486
1487 err = -ENOTCONN;
1488 if (sk->sk_user_data == NULL)
1489 goto end;
1490
1491 /* Get the session context */
1492 err = -EBADF;
1493 session = pppol2tp_sock_to_session(sk);
1494 if (session == NULL)
1495 goto end;
1496
1497 /* Special case: if session_id == 0x0000, treat as operation on tunnel */
1498 ps = l2tp_session_priv(session);
1499 if ((session->session_id == 0) &&
1500 (session->peer_session_id == 0)) {
1501 err = -EBADF;
1502 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1503 if (tunnel == NULL)
1504 goto end_put_sess;
1505
1506 err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
1507 sock_put(ps->tunnel_sock);
1508 } else
1509 err = pppol2tp_session_getsockopt(sk, session, optname, &val);
1510
1511 err = -EFAULT;
1512 if (put_user(len, (int __user *) optlen))
1513 goto end_put_sess;
1514
1515 if (copy_to_user((void __user *) optval, &val, len))
1516 goto end_put_sess;
1517
1518 err = 0;
1519
1520 end_put_sess:
1521 sock_put(sk);
1522 end:
1523 return err;
1524 }
1525
1526 /*****************************************************************************
1527 * /proc filesystem for debug
1528 * Since the original pppol2tp driver provided /proc/net/pppol2tp for
1529 * L2TPv2, we dump only L2TPv2 tunnels and sessions here.
1530 *****************************************************************************/
1531
1532 static unsigned int pppol2tp_net_id;
1533
1534 #ifdef CONFIG_PROC_FS
1535
1536 struct pppol2tp_seq_data {
1537 struct seq_net_private p;
1538 int tunnel_idx; /* current tunnel */
1539 int session_idx; /* index of session within current tunnel */
1540 struct l2tp_tunnel *tunnel;
1541 struct l2tp_session *session; /* NULL means get next tunnel */
1542 };
1543
1544 static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd)
1545 {
1546 for (;;) {
1547 pd->tunnel = l2tp_tunnel_find_nth(net, pd->tunnel_idx);
1548 pd->tunnel_idx++;
1549
1550 if (pd->tunnel == NULL)
1551 break;
1552
1553 /* Ignore L2TPv3 tunnels */
1554 if (pd->tunnel->version < 3)
1555 break;
1556 }
1557 }
1558
1559 static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd)
1560 {
1561 pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx);
1562 pd->session_idx++;
1563
1564 if (pd->session == NULL) {
1565 pd->session_idx = 0;
1566 pppol2tp_next_tunnel(net, pd);
1567 }
1568 }
1569
1570 static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
1571 {
1572 struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
1573 loff_t pos = *offs;
1574 struct net *net;
1575
1576 if (!pos)
1577 goto out;
1578
1579 BUG_ON(m->private == NULL);
1580 pd = m->private;
1581 net = seq_file_net(m);
1582
1583 if (pd->tunnel == NULL)
1584 pppol2tp_next_tunnel(net, pd);
1585 else
1586 pppol2tp_next_session(net, pd);
1587
1588 /* NULL tunnel and session indicates end of list */
1589 if ((pd->tunnel == NULL) && (pd->session == NULL))
1590 pd = NULL;
1591
1592 out:
1593 return pd;
1594 }
1595
1596 static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
1597 {
1598 (*pos)++;
1599 return NULL;
1600 }
1601
1602 static void pppol2tp_seq_stop(struct seq_file *p, void *v)
1603 {
1604 /* nothing to do */
1605 }
1606
1607 static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
1608 {
1609 struct l2tp_tunnel *tunnel = v;
1610
1611 seq_printf(m, "\nTUNNEL '%s', %c %d\n",
1612 tunnel->name,
1613 (tunnel == tunnel->sock->sk_user_data) ? 'Y' : 'N',
1614 atomic_read(&tunnel->ref_count) - 1);
1615 seq_printf(m, " %08x %llu/%llu/%llu %llu/%llu/%llu\n",
1616 tunnel->debug,
1617 (unsigned long long)tunnel->stats.tx_packets,
1618 (unsigned long long)tunnel->stats.tx_bytes,
1619 (unsigned long long)tunnel->stats.tx_errors,
1620 (unsigned long long)tunnel->stats.rx_packets,
1621 (unsigned long long)tunnel->stats.rx_bytes,
1622 (unsigned long long)tunnel->stats.rx_errors);
1623 }
1624
1625 static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
1626 {
1627 struct l2tp_session *session = v;
1628 struct l2tp_tunnel *tunnel = session->tunnel;
1629 struct pppol2tp_session *ps = l2tp_session_priv(session);
1630 struct pppox_sock *po = pppox_sk(ps->sock);
1631 u32 ip = 0;
1632 u16 port = 0;
1633
1634 if (tunnel->sock) {
1635 struct inet_sock *inet = inet_sk(tunnel->sock);
1636 ip = ntohl(inet->inet_saddr);
1637 port = ntohs(inet->inet_sport);
1638 }
1639
1640 seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
1641 "%04X/%04X %d %c\n",
1642 session->name, ip, port,
1643 tunnel->tunnel_id,
1644 session->session_id,
1645 tunnel->peer_tunnel_id,
1646 session->peer_session_id,
1647 ps->sock->sk_state,
1648 (session == ps->sock->sk_user_data) ?
1649 'Y' : 'N');
1650 seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n",
1651 session->mtu, session->mru,
1652 session->recv_seq ? 'R' : '-',
1653 session->send_seq ? 'S' : '-',
1654 session->lns_mode ? "LNS" : "LAC",
1655 session->debug,
1656 jiffies_to_msecs(session->reorder_timeout));
1657 seq_printf(m, " %hu/%hu %llu/%llu/%llu %llu/%llu/%llu\n",
1658 session->nr, session->ns,
1659 (unsigned long long)session->stats.tx_packets,
1660 (unsigned long long)session->stats.tx_bytes,
1661 (unsigned long long)session->stats.tx_errors,
1662 (unsigned long long)session->stats.rx_packets,
1663 (unsigned long long)session->stats.rx_bytes,
1664 (unsigned long long)session->stats.rx_errors);
1665
1666 if (po)
1667 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
1668 }
1669
1670 static int pppol2tp_seq_show(struct seq_file *m, void *v)
1671 {
1672 struct pppol2tp_seq_data *pd = v;
1673
1674 /* display header on line 1 */
1675 if (v == SEQ_START_TOKEN) {
1676 seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
1677 seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
1678 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1679 seq_puts(m, " SESSION name, addr/port src-tid/sid "
1680 "dest-tid/sid state user-data-ok\n");
1681 seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
1682 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1683 goto out;
1684 }
1685
1686 /* Show the tunnel or session context.
1687 */
1688 if (pd->session == NULL)
1689 pppol2tp_seq_tunnel_show(m, pd->tunnel);
1690 else
1691 pppol2tp_seq_session_show(m, pd->session);
1692
1693 out:
1694 return 0;
1695 }
1696
1697 static const struct seq_operations pppol2tp_seq_ops = {
1698 .start = pppol2tp_seq_start,
1699 .next = pppol2tp_seq_next,
1700 .stop = pppol2tp_seq_stop,
1701 .show = pppol2tp_seq_show,
1702 };
1703
1704 /* Called when our /proc file is opened. We allocate data for use when
1705 * iterating our tunnel / session contexts and store it in the private
1706 * data of the seq_file.
1707 */
1708 static int pppol2tp_proc_open(struct inode *inode, struct file *file)
1709 {
1710 return seq_open_net(inode, file, &pppol2tp_seq_ops,
1711 sizeof(struct pppol2tp_seq_data));
1712 }
1713
1714 static const struct file_operations pppol2tp_proc_fops = {
1715 .owner = THIS_MODULE,
1716 .open = pppol2tp_proc_open,
1717 .read = seq_read,
1718 .llseek = seq_lseek,
1719 .release = seq_release_net,
1720 };
1721
1722 #endif /* CONFIG_PROC_FS */
1723
1724 /*****************************************************************************
1725 * Network namespace
1726 *****************************************************************************/
1727
1728 static __net_init int pppol2tp_init_net(struct net *net)
1729 {
1730 struct proc_dir_entry *pde;
1731 int err = 0;
1732
1733 pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops);
1734 if (!pde) {
1735 err = -ENOMEM;
1736 goto out;
1737 }
1738
1739 out:
1740 return err;
1741 }
1742
1743 static __net_exit void pppol2tp_exit_net(struct net *net)
1744 {
1745 proc_net_remove(net, "pppol2tp");
1746 }
1747
1748 static struct pernet_operations pppol2tp_net_ops = {
1749 .init = pppol2tp_init_net,
1750 .exit = pppol2tp_exit_net,
1751 .id = &pppol2tp_net_id,
1752 };
1753
1754 /*****************************************************************************
1755 * Init and cleanup
1756 *****************************************************************************/
1757
1758 static const struct proto_ops pppol2tp_ops = {
1759 .family = AF_PPPOX,
1760 .owner = THIS_MODULE,
1761 .release = pppol2tp_release,
1762 .bind = sock_no_bind,
1763 .connect = pppol2tp_connect,
1764 .socketpair = sock_no_socketpair,
1765 .accept = sock_no_accept,
1766 .getname = pppol2tp_getname,
1767 .poll = datagram_poll,
1768 .listen = sock_no_listen,
1769 .shutdown = sock_no_shutdown,
1770 .setsockopt = pppol2tp_setsockopt,
1771 .getsockopt = pppol2tp_getsockopt,
1772 .sendmsg = pppol2tp_sendmsg,
1773 .recvmsg = pppol2tp_recvmsg,
1774 .mmap = sock_no_mmap,
1775 .ioctl = pppox_ioctl,
1776 };
1777
1778 static const struct pppox_proto pppol2tp_proto = {
1779 .create = pppol2tp_create,
1780 .ioctl = pppol2tp_ioctl
1781 };
1782
1783 #ifdef CONFIG_L2TP_V3
1784
1785 static const struct l2tp_nl_cmd_ops pppol2tp_nl_cmd_ops = {
1786 .session_create = pppol2tp_session_create,
1787 .session_delete = pppol2tp_session_delete,
1788 };
1789
1790 #endif /* CONFIG_L2TP_V3 */
1791
1792 static int __init pppol2tp_init(void)
1793 {
1794 int err;
1795
1796 err = register_pernet_device(&pppol2tp_net_ops);
1797 if (err)
1798 goto out;
1799
1800 err = proto_register(&pppol2tp_sk_proto, 0);
1801 if (err)
1802 goto out_unregister_pppol2tp_pernet;
1803
1804 err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
1805 if (err)
1806 goto out_unregister_pppol2tp_proto;
1807
1808 #ifdef CONFIG_L2TP_V3
1809 err = l2tp_nl_register_ops(L2TP_PWTYPE_PPP, &pppol2tp_nl_cmd_ops);
1810 if (err)
1811 goto out_unregister_pppox;
1812 #endif
1813
1814 printk(KERN_INFO "PPPoL2TP kernel driver, %s\n",
1815 PPPOL2TP_DRV_VERSION);
1816
1817 out:
1818 return err;
1819
1820 #ifdef CONFIG_L2TP_V3
1821 out_unregister_pppox:
1822 unregister_pppox_proto(PX_PROTO_OL2TP);
1823 #endif
1824 out_unregister_pppol2tp_proto:
1825 proto_unregister(&pppol2tp_sk_proto);
1826 out_unregister_pppol2tp_pernet:
1827 unregister_pernet_device(&pppol2tp_net_ops);
1828 goto out;
1829 }
1830
1831 static void __exit pppol2tp_exit(void)
1832 {
1833 #ifdef CONFIG_L2TP_V3
1834 l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
1835 #endif
1836 unregister_pppox_proto(PX_PROTO_OL2TP);
1837 proto_unregister(&pppol2tp_sk_proto);
1838 unregister_pernet_device(&pppol2tp_net_ops);
1839 }
1840
1841 module_init(pppol2tp_init);
1842 module_exit(pppol2tp_exit);
1843
1844 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1845 MODULE_DESCRIPTION("PPP over L2TP over UDP");
1846 MODULE_LICENSE("GPL");
1847 MODULE_VERSION(PPPOL2TP_DRV_VERSION);