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tty/serial: atmel_serial: whitespace and braces modifications
[zen-stable.git] / net / l2tp / l2tp_ppp.c
blobf42cd091596602181f7d1a54ac0992a6ef40f371
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
399 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
400 goto abort;
401
402 /* Get session and tunnel contexts from the socket */
403 session = pppol2tp_sock_to_session(sk);
404 if (session == NULL)
405 goto abort;
406
407 ps = l2tp_session_priv(session);
408 sk_tun = ps->tunnel_sock;
409 if (sk_tun == NULL)
410 goto abort_put_sess;
411 tunnel = l2tp_sock_to_tunnel(sk_tun);
412 if (tunnel == NULL)
413 goto abort_put_sess;
414
415 old_headroom = skb_headroom(skb);
416 if (skb_cow_head(skb, sizeof(ppph)))
417 goto abort_put_sess_tun;
418
419 new_headroom = skb_headroom(skb);
420 skb->truesize += new_headroom - old_headroom;
421
422 /* Setup PPP header */
423 __skb_push(skb, sizeof(ppph));
424 skb->data[0] = ppph[0];
425 skb->data[1] = ppph[1];
426
427 l2tp_xmit_skb(session, skb, session->hdr_len);
428
429 sock_put(sk_tun);
430 sock_put(sk);
431 return 1;
432
433 abort_put_sess_tun:
434 sock_put(sk_tun);
435 abort_put_sess:
436 sock_put(sk);
437 abort:
438 /* Free the original skb */
439 kfree_skb(skb);
440 return 1;
441 }
442
443 /*****************************************************************************
444 * Session (and tunnel control) socket create/destroy.
445 *****************************************************************************/
446
447 /* Called by l2tp_core when a session socket is being closed.
448 */
449 static void pppol2tp_session_close(struct l2tp_session *session)
450 {
451 struct pppol2tp_session *ps = l2tp_session_priv(session);
452 struct sock *sk = ps->sock;
453 struct sk_buff *skb;
454
455 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
456
457 if (session->session_id == 0)
458 goto out;
459
460 if (sk != NULL) {
461 lock_sock(sk);
462
463 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
464 pppox_unbind_sock(sk);
465 sk->sk_state = PPPOX_DEAD;
466 sk->sk_state_change(sk);
467 }
468
469 /* Purge any queued data */
470 skb_queue_purge(&sk->sk_receive_queue);
471 skb_queue_purge(&sk->sk_write_queue);
472 while ((skb = skb_dequeue(&session->reorder_q))) {
473 kfree_skb(skb);
474 sock_put(sk);
475 }
476
477 release_sock(sk);
478 }
479
480 out:
481 return;
482 }
483
484 /* Really kill the session socket. (Called from sock_put() if
485 * refcnt == 0.)
486 */
487 static void pppol2tp_session_destruct(struct sock *sk)
488 {
489 struct l2tp_session *session;
490
491 if (sk->sk_user_data != NULL) {
492 session = sk->sk_user_data;
493 if (session == NULL)
494 goto out;
495
496 sk->sk_user_data = NULL;
497 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
498 l2tp_session_dec_refcount(session);
499 }
500
501 out:
502 return;
503 }
504
505 /* Called when the PPPoX socket (session) is closed.
506 */
507 static int pppol2tp_release(struct socket *sock)
508 {
509 struct sock *sk = sock->sk;
510 struct l2tp_session *session;
511 int error;
512
513 if (!sk)
514 return 0;
515
516 error = -EBADF;
517 lock_sock(sk);
518 if (sock_flag(sk, SOCK_DEAD) != 0)
519 goto error;
520
521 pppox_unbind_sock(sk);
522
523 /* Signal the death of the socket. */
524 sk->sk_state = PPPOX_DEAD;
525 sock_orphan(sk);
526 sock->sk = NULL;
527
528 session = pppol2tp_sock_to_session(sk);
529
530 /* Purge any queued data */
531 skb_queue_purge(&sk->sk_receive_queue);
532 skb_queue_purge(&sk->sk_write_queue);
533 if (session != NULL) {
534 struct sk_buff *skb;
535 while ((skb = skb_dequeue(&session->reorder_q))) {
536 kfree_skb(skb);
537 sock_put(sk);
538 }
539 sock_put(sk);
540 }
541
542 release_sock(sk);
543
544 /* This will delete the session context via
545 * pppol2tp_session_destruct() if the socket's refcnt drops to
546 * zero.
547 */
548 sock_put(sk);
549
550 return 0;
551
552 error:
553 release_sock(sk);
554 return error;
555 }
556
557 static struct proto pppol2tp_sk_proto = {
558 .name = "PPPOL2TP",
559 .owner = THIS_MODULE,
560 .obj_size = sizeof(struct pppox_sock),
561 };
562
563 static int pppol2tp_backlog_recv(struct sock *sk, struct sk_buff *skb)
564 {
565 int rc;
566
567 rc = l2tp_udp_encap_recv(sk, skb);
568 if (rc)
569 kfree_skb(skb);
570
571 return NET_RX_SUCCESS;
572 }
573
574 /* socket() handler. Initialize a new struct sock.
575 */
576 static int pppol2tp_create(struct net *net, struct socket *sock)
577 {
578 int error = -ENOMEM;
579 struct sock *sk;
580
581 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto);
582 if (!sk)
583 goto out;
584
585 sock_init_data(sock, sk);
586
587 sock->state = SS_UNCONNECTED;
588 sock->ops = &pppol2tp_ops;
589
590 sk->sk_backlog_rcv = pppol2tp_backlog_recv;
591 sk->sk_protocol = PX_PROTO_OL2TP;
592 sk->sk_family = PF_PPPOX;
593 sk->sk_state = PPPOX_NONE;
594 sk->sk_type = SOCK_STREAM;
595 sk->sk_destruct = pppol2tp_session_destruct;
596
597 error = 0;
598
599 out:
600 return error;
601 }
602
603 #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
604 static void pppol2tp_show(struct seq_file *m, void *arg)
605 {
606 struct l2tp_session *session = arg;
607 struct pppol2tp_session *ps = l2tp_session_priv(session);
608
609 if (ps) {
610 struct pppox_sock *po = pppox_sk(ps->sock);
611 if (po)
612 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
613 }
614 }
615 #endif
616
617 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
618 */
619 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
620 int sockaddr_len, int flags)
621 {
622 struct sock *sk = sock->sk;
623 struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
624 struct sockaddr_pppol2tpv3 *sp3 = (struct sockaddr_pppol2tpv3 *) uservaddr;
625 struct pppox_sock *po = pppox_sk(sk);
626 struct l2tp_session *session = NULL;
627 struct l2tp_tunnel *tunnel;
628 struct pppol2tp_session *ps;
629 struct dst_entry *dst;
630 struct l2tp_session_cfg cfg = { 0, };
631 int error = 0;
632 u32 tunnel_id, peer_tunnel_id;
633 u32 session_id, peer_session_id;
634 int ver = 2;
635 int fd;
636
637 lock_sock(sk);
638
639 error = -EINVAL;
640 if (sp->sa_protocol != PX_PROTO_OL2TP)
641 goto end;
642
643 /* Check for already bound sockets */
644 error = -EBUSY;
645 if (sk->sk_state & PPPOX_CONNECTED)
646 goto end;
647
648 /* We don't supporting rebinding anyway */
649 error = -EALREADY;
650 if (sk->sk_user_data)
651 goto end; /* socket is already attached */
652
653 /* Get params from socket address. Handle L2TPv2 and L2TPv3 */
654 if (sockaddr_len == sizeof(struct sockaddr_pppol2tp)) {
655 fd = sp->pppol2tp.fd;
656 tunnel_id = sp->pppol2tp.s_tunnel;
657 peer_tunnel_id = sp->pppol2tp.d_tunnel;
658 session_id = sp->pppol2tp.s_session;
659 peer_session_id = sp->pppol2tp.d_session;
660 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3)) {
661 ver = 3;
662 fd = sp3->pppol2tp.fd;
663 tunnel_id = sp3->pppol2tp.s_tunnel;
664 peer_tunnel_id = sp3->pppol2tp.d_tunnel;
665 session_id = sp3->pppol2tp.s_session;
666 peer_session_id = sp3->pppol2tp.d_session;
667 } else {
668 error = -EINVAL;
669 goto end; /* bad socket address */
670 }
671
672 /* Don't bind if tunnel_id is 0 */
673 error = -EINVAL;
674 if (tunnel_id == 0)
675 goto end;
676
677 tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id);
678
679 /* Special case: create tunnel context if session_id and
680 * peer_session_id is 0. Otherwise look up tunnel using supplied
681 * tunnel id.
682 */
683 if ((session_id == 0) && (peer_session_id == 0)) {
684 if (tunnel == NULL) {
685 struct l2tp_tunnel_cfg tcfg = {
686 .encap = L2TP_ENCAPTYPE_UDP,
687 .debug = 0,
688 };
689 error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, &tcfg, &tunnel);
690 if (error < 0)
691 goto end;
692 }
693 } else {
694 /* Error if we can't find the tunnel */
695 error = -ENOENT;
696 if (tunnel == NULL)
697 goto end;
698
699 /* Error if socket is not prepped */
700 if (tunnel->sock == NULL)
701 goto end;
702 }
703
704 if (tunnel->recv_payload_hook == NULL)
705 tunnel->recv_payload_hook = pppol2tp_recv_payload_hook;
706
707 if (tunnel->peer_tunnel_id == 0) {
708 if (ver == 2)
709 tunnel->peer_tunnel_id = sp->pppol2tp.d_tunnel;
710 else
711 tunnel->peer_tunnel_id = sp3->pppol2tp.d_tunnel;
712 }
713
714 /* Create session if it doesn't already exist. We handle the
715 * case where a session was previously created by the netlink
716 * interface by checking that the session doesn't already have
717 * a socket and its tunnel socket are what we expect. If any
718 * of those checks fail, return EEXIST to the caller.
719 */
720 session = l2tp_session_find(sock_net(sk), tunnel, session_id);
721 if (session == NULL) {
722 /* Default MTU must allow space for UDP/L2TP/PPP
723 * headers.
724 */
725 cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
726
727 /* Allocate and initialize a new session context. */
728 session = l2tp_session_create(sizeof(struct pppol2tp_session),
729 tunnel, session_id,
730 peer_session_id, &cfg);
731 if (session == NULL) {
732 error = -ENOMEM;
733 goto end;
734 }
735 } else {
736 ps = l2tp_session_priv(session);
737 error = -EEXIST;
738 if (ps->sock != NULL)
739 goto end;
740
741 /* consistency checks */
742 if (ps->tunnel_sock != tunnel->sock)
743 goto end;
744 }
745
746 /* Associate session with its PPPoL2TP socket */
747 ps = l2tp_session_priv(session);
748 ps->owner = current->pid;
749 ps->sock = sk;
750 ps->tunnel_sock = tunnel->sock;
751
752 session->recv_skb = pppol2tp_recv;
753 session->session_close = pppol2tp_session_close;
754 #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
755 session->show = pppol2tp_show;
756 #endif
757
758 /* We need to know each time a skb is dropped from the reorder
759 * queue.
760 */
761 session->ref = pppol2tp_session_sock_hold;
762 session->deref = pppol2tp_session_sock_put;
763
764 /* If PMTU discovery was enabled, use the MTU that was discovered */
765 dst = sk_dst_get(sk);
766 if (dst != NULL) {
767 u32 pmtu = dst_mtu(__sk_dst_get(sk));
768 if (pmtu != 0)
769 session->mtu = session->mru = pmtu -
770 PPPOL2TP_HEADER_OVERHEAD;
771 dst_release(dst);
772 }
773
774 /* Special case: if source & dest session_id == 0x0000, this
775 * socket is being created to manage the tunnel. Just set up
776 * the internal context for use by ioctl() and sockopt()
777 * handlers.
778 */
779 if ((session->session_id == 0) &&
780 (session->peer_session_id == 0)) {
781 error = 0;
782 goto out_no_ppp;
783 }
784
785 /* The only header we need to worry about is the L2TP
786 * header. This size is different depending on whether
787 * sequence numbers are enabled for the data channel.
788 */
789 po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
790
791 po->chan.private = sk;
792 po->chan.ops = &pppol2tp_chan_ops;
793 po->chan.mtu = session->mtu;
794
795 error = ppp_register_net_channel(sock_net(sk), &po->chan);
796 if (error)
797 goto end;
798
799 out_no_ppp:
800 /* This is how we get the session context from the socket. */
801 sk->sk_user_data = session;
802 sk->sk_state = PPPOX_CONNECTED;
803 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
804 "%s: created\n", session->name);
805
806 end:
807 release_sock(sk);
808
809 return error;
810 }
811
812 #ifdef CONFIG_L2TP_V3
813
814 /* Called when creating sessions via the netlink interface.
815 */
816 static int pppol2tp_session_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
817 {
818 int error;
819 struct l2tp_tunnel *tunnel;
820 struct l2tp_session *session;
821 struct pppol2tp_session *ps;
822
823 tunnel = l2tp_tunnel_find(net, tunnel_id);
824
825 /* Error if we can't find the tunnel */
826 error = -ENOENT;
827 if (tunnel == NULL)
828 goto out;
829
830 /* Error if tunnel socket is not prepped */
831 if (tunnel->sock == NULL)
832 goto out;
833
834 /* Check that this session doesn't already exist */
835 error = -EEXIST;
836 session = l2tp_session_find(net, tunnel, session_id);
837 if (session != NULL)
838 goto out;
839
840 /* Default MTU values. */
841 if (cfg->mtu == 0)
842 cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
843 if (cfg->mru == 0)
844 cfg->mru = cfg->mtu;
845
846 /* Allocate and initialize a new session context. */
847 error = -ENOMEM;
848 session = l2tp_session_create(sizeof(struct pppol2tp_session),
849 tunnel, session_id,
850 peer_session_id, cfg);
851 if (session == NULL)
852 goto out;
853
854 ps = l2tp_session_priv(session);
855 ps->tunnel_sock = tunnel->sock;
856
857 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
858 "%s: created\n", session->name);
859
860 error = 0;
861
862 out:
863 return error;
864 }
865
866 /* Called when deleting sessions via the netlink interface.
867 */
868 static int pppol2tp_session_delete(struct l2tp_session *session)
869 {
870 struct pppol2tp_session *ps = l2tp_session_priv(session);
871
872 if (ps->sock == NULL)
873 l2tp_session_dec_refcount(session);
874
875 return 0;
876 }
877
878 #endif /* CONFIG_L2TP_V3 */
879
880 /* getname() support.
881 */
882 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
883 int *usockaddr_len, int peer)
884 {
885 int len = 0;
886 int error = 0;
887 struct l2tp_session *session;
888 struct l2tp_tunnel *tunnel;
889 struct sock *sk = sock->sk;
890 struct inet_sock *inet;
891 struct pppol2tp_session *pls;
892
893 error = -ENOTCONN;
894 if (sk == NULL)
895 goto end;
896 if (sk->sk_state != PPPOX_CONNECTED)
897 goto end;
898
899 error = -EBADF;
900 session = pppol2tp_sock_to_session(sk);
901 if (session == NULL)
902 goto end;
903
904 pls = l2tp_session_priv(session);
905 tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock);
906 if (tunnel == NULL) {
907 error = -EBADF;
908 goto end_put_sess;
909 }
910
911 inet = inet_sk(sk);
912 if (tunnel->version == 2) {
913 struct sockaddr_pppol2tp sp;
914 len = sizeof(sp);
915 memset(&sp, 0, len);
916 sp.sa_family = AF_PPPOX;
917 sp.sa_protocol = PX_PROTO_OL2TP;
918 sp.pppol2tp.fd = tunnel->fd;
919 sp.pppol2tp.pid = pls->owner;
920 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
921 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
922 sp.pppol2tp.s_session = session->session_id;
923 sp.pppol2tp.d_session = session->peer_session_id;
924 sp.pppol2tp.addr.sin_family = AF_INET;
925 sp.pppol2tp.addr.sin_port = inet->inet_dport;
926 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
927 memcpy(uaddr, &sp, len);
928 } else if (tunnel->version == 3) {
929 struct sockaddr_pppol2tpv3 sp;
930 len = sizeof(sp);
931 memset(&sp, 0, len);
932 sp.sa_family = AF_PPPOX;
933 sp.sa_protocol = PX_PROTO_OL2TP;
934 sp.pppol2tp.fd = tunnel->fd;
935 sp.pppol2tp.pid = pls->owner;
936 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
937 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
938 sp.pppol2tp.s_session = session->session_id;
939 sp.pppol2tp.d_session = session->peer_session_id;
940 sp.pppol2tp.addr.sin_family = AF_INET;
941 sp.pppol2tp.addr.sin_port = inet->inet_dport;
942 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
943 memcpy(uaddr, &sp, len);
944 }
945
946 *usockaddr_len = len;
947
948 sock_put(pls->tunnel_sock);
949 end_put_sess:
950 sock_put(sk);
951 error = 0;
952
953 end:
954 return error;
955 }
956
957 /****************************************************************************
958 * ioctl() handlers.
959 *
960 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
961 * sockets. However, in order to control kernel tunnel features, we allow
962 * userspace to create a special "tunnel" PPPoX socket which is used for
963 * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
964 * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
965 * calls.
966 ****************************************************************************/
967
968 static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest,
969 struct l2tp_stats *stats)
970 {
971 dest->tx_packets = stats->tx_packets;
972 dest->tx_bytes = stats->tx_bytes;
973 dest->tx_errors = stats->tx_errors;
974 dest->rx_packets = stats->rx_packets;
975 dest->rx_bytes = stats->rx_bytes;
976 dest->rx_seq_discards = stats->rx_seq_discards;
977 dest->rx_oos_packets = stats->rx_oos_packets;
978 dest->rx_errors = stats->rx_errors;
979 }
980
981 /* Session ioctl helper.
982 */
983 static int pppol2tp_session_ioctl(struct l2tp_session *session,
984 unsigned int cmd, unsigned long arg)
985 {
986 struct ifreq ifr;
987 int err = 0;
988 struct sock *sk;
989 int val = (int) arg;
990 struct pppol2tp_session *ps = l2tp_session_priv(session);
991 struct l2tp_tunnel *tunnel = session->tunnel;
992 struct pppol2tp_ioc_stats stats;
993
994 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
995 "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n",
996 session->name, cmd, arg);
997
998 sk = ps->sock;
999 sock_hold(sk);
1000
1001 switch (cmd) {
1002 case SIOCGIFMTU:
1003 err = -ENXIO;
1004 if (!(sk->sk_state & PPPOX_CONNECTED))
1005 break;
1006
1007 err = -EFAULT;
1008 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1009 break;
1010 ifr.ifr_mtu = session->mtu;
1011 if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq)))
1012 break;
1013
1014 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1015 "%s: get mtu=%d\n", session->name, session->mtu);
1016 err = 0;
1017 break;
1018
1019 case SIOCSIFMTU:
1020 err = -ENXIO;
1021 if (!(sk->sk_state & PPPOX_CONNECTED))
1022 break;
1023
1024 err = -EFAULT;
1025 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1026 break;
1027
1028 session->mtu = ifr.ifr_mtu;
1029
1030 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1031 "%s: set mtu=%d\n", session->name, session->mtu);
1032 err = 0;
1033 break;
1034
1035 case PPPIOCGMRU:
1036 err = -ENXIO;
1037 if (!(sk->sk_state & PPPOX_CONNECTED))
1038 break;
1039
1040 err = -EFAULT;
1041 if (put_user(session->mru, (int __user *) arg))
1042 break;
1043
1044 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1045 "%s: get mru=%d\n", session->name, session->mru);
1046 err = 0;
1047 break;
1048
1049 case PPPIOCSMRU:
1050 err = -ENXIO;
1051 if (!(sk->sk_state & PPPOX_CONNECTED))
1052 break;
1053
1054 err = -EFAULT;
1055 if (get_user(val, (int __user *) arg))
1056 break;
1057
1058 session->mru = val;
1059 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1060 "%s: set mru=%d\n", session->name, session->mru);
1061 err = 0;
1062 break;
1063
1064 case PPPIOCGFLAGS:
1065 err = -EFAULT;
1066 if (put_user(ps->flags, (int __user *) arg))
1067 break;
1068
1069 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1070 "%s: get flags=%d\n", session->name, ps->flags);
1071 err = 0;
1072 break;
1073
1074 case PPPIOCSFLAGS:
1075 err = -EFAULT;
1076 if (get_user(val, (int __user *) arg))
1077 break;
1078 ps->flags = val;
1079 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1080 "%s: set flags=%d\n", session->name, ps->flags);
1081 err = 0;
1082 break;
1083
1084 case PPPIOCGL2TPSTATS:
1085 err = -ENXIO;
1086 if (!(sk->sk_state & PPPOX_CONNECTED))
1087 break;
1088
1089 memset(&stats, 0, sizeof(stats));
1090 stats.tunnel_id = tunnel->tunnel_id;
1091 stats.session_id = session->session_id;
1092 pppol2tp_copy_stats(&stats, &session->stats);
1093 if (copy_to_user((void __user *) arg, &stats,
1094 sizeof(stats)))
1095 break;
1096 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1097 "%s: get L2TP stats\n", session->name);
1098 err = 0;
1099 break;
1100
1101 default:
1102 err = -ENOSYS;
1103 break;
1104 }
1105
1106 sock_put(sk);
1107
1108 return err;
1109 }
1110
1111 /* Tunnel ioctl helper.
1112 *
1113 * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data
1114 * specifies a session_id, the session ioctl handler is called. This allows an
1115 * application to retrieve session stats via a tunnel socket.
1116 */
1117 static int pppol2tp_tunnel_ioctl(struct l2tp_tunnel *tunnel,
1118 unsigned int cmd, unsigned long arg)
1119 {
1120 int err = 0;
1121 struct sock *sk;
1122 struct pppol2tp_ioc_stats stats;
1123
1124 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG,
1125 "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n",
1126 tunnel->name, cmd, arg);
1127
1128 sk = tunnel->sock;
1129 sock_hold(sk);
1130
1131 switch (cmd) {
1132 case PPPIOCGL2TPSTATS:
1133 err = -ENXIO;
1134 if (!(sk->sk_state & PPPOX_CONNECTED))
1135 break;
1136
1137 if (copy_from_user(&stats, (void __user *) arg,
1138 sizeof(stats))) {
1139 err = -EFAULT;
1140 break;
1141 }
1142 if (stats.session_id != 0) {
1143 /* resend to session ioctl handler */
1144 struct l2tp_session *session =
1145 l2tp_session_find(sock_net(sk), tunnel, stats.session_id);
1146 if (session != NULL)
1147 err = pppol2tp_session_ioctl(session, cmd, arg);
1148 else
1149 err = -EBADR;
1150 break;
1151 }
1152 #ifdef CONFIG_XFRM
1153 stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0;
1154 #endif
1155 pppol2tp_copy_stats(&stats, &tunnel->stats);
1156 if (copy_to_user((void __user *) arg, &stats, sizeof(stats))) {
1157 err = -EFAULT;
1158 break;
1159 }
1160 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1161 "%s: get L2TP stats\n", tunnel->name);
1162 err = 0;
1163 break;
1164
1165 default:
1166 err = -ENOSYS;
1167 break;
1168 }
1169
1170 sock_put(sk);
1171
1172 return err;
1173 }
1174
1175 /* Main ioctl() handler.
1176 * Dispatch to tunnel or session helpers depending on the socket.
1177 */
1178 static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
1179 unsigned long arg)
1180 {
1181 struct sock *sk = sock->sk;
1182 struct l2tp_session *session;
1183 struct l2tp_tunnel *tunnel;
1184 struct pppol2tp_session *ps;
1185 int err;
1186
1187 if (!sk)
1188 return 0;
1189
1190 err = -EBADF;
1191 if (sock_flag(sk, SOCK_DEAD) != 0)
1192 goto end;
1193
1194 err = -ENOTCONN;
1195 if ((sk->sk_user_data == NULL) ||
1196 (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND))))
1197 goto end;
1198
1199 /* Get session context from the socket */
1200 err = -EBADF;
1201 session = pppol2tp_sock_to_session(sk);
1202 if (session == NULL)
1203 goto end;
1204
1205 /* Special case: if session's session_id is zero, treat ioctl as a
1206 * tunnel ioctl
1207 */
1208 ps = l2tp_session_priv(session);
1209 if ((session->session_id == 0) &&
1210 (session->peer_session_id == 0)) {
1211 err = -EBADF;
1212 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1213 if (tunnel == NULL)
1214 goto end_put_sess;
1215
1216 err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
1217 sock_put(ps->tunnel_sock);
1218 goto end_put_sess;
1219 }
1220
1221 err = pppol2tp_session_ioctl(session, cmd, arg);
1222
1223 end_put_sess:
1224 sock_put(sk);
1225 end:
1226 return err;
1227 }
1228
1229 /*****************************************************************************
1230 * setsockopt() / getsockopt() support.
1231 *
1232 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1233 * sockets. In order to control kernel tunnel features, we allow userspace to
1234 * create a special "tunnel" PPPoX socket which is used for control only.
1235 * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
1236 * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
1237 *****************************************************************************/
1238
1239 /* Tunnel setsockopt() helper.
1240 */
1241 static int pppol2tp_tunnel_setsockopt(struct sock *sk,
1242 struct l2tp_tunnel *tunnel,
1243 int optname, int val)
1244 {
1245 int err = 0;
1246
1247 switch (optname) {
1248 case PPPOL2TP_SO_DEBUG:
1249 tunnel->debug = val;
1250 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1251 "%s: set debug=%x\n", tunnel->name, tunnel->debug);
1252 break;
1253
1254 default:
1255 err = -ENOPROTOOPT;
1256 break;
1257 }
1258
1259 return err;
1260 }
1261
1262 /* Session setsockopt helper.
1263 */
1264 static int pppol2tp_session_setsockopt(struct sock *sk,
1265 struct l2tp_session *session,
1266 int optname, int val)
1267 {
1268 int err = 0;
1269 struct pppol2tp_session *ps = l2tp_session_priv(session);
1270
1271 switch (optname) {
1272 case PPPOL2TP_SO_RECVSEQ:
1273 if ((val != 0) && (val != 1)) {
1274 err = -EINVAL;
1275 break;
1276 }
1277 session->recv_seq = val ? -1 : 0;
1278 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1279 "%s: set recv_seq=%d\n", session->name, session->recv_seq);
1280 break;
1281
1282 case PPPOL2TP_SO_SENDSEQ:
1283 if ((val != 0) && (val != 1)) {
1284 err = -EINVAL;
1285 break;
1286 }
1287 session->send_seq = val ? -1 : 0;
1288 {
1289 struct sock *ssk = ps->sock;
1290 struct pppox_sock *po = pppox_sk(ssk);
1291 po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
1292 PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
1293 }
1294 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1295 "%s: set send_seq=%d\n", session->name, session->send_seq);
1296 break;
1297
1298 case PPPOL2TP_SO_LNSMODE:
1299 if ((val != 0) && (val != 1)) {
1300 err = -EINVAL;
1301 break;
1302 }
1303 session->lns_mode = val ? -1 : 0;
1304 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1305 "%s: set lns_mode=%d\n", session->name, session->lns_mode);
1306 break;
1307
1308 case PPPOL2TP_SO_DEBUG:
1309 session->debug = val;
1310 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1311 "%s: set debug=%x\n", session->name, session->debug);
1312 break;
1313
1314 case PPPOL2TP_SO_REORDERTO:
1315 session->reorder_timeout = msecs_to_jiffies(val);
1316 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1317 "%s: set reorder_timeout=%d\n", session->name, session->reorder_timeout);
1318 break;
1319
1320 default:
1321 err = -ENOPROTOOPT;
1322 break;
1323 }
1324
1325 return err;
1326 }
1327
1328 /* Main setsockopt() entry point.
1329 * Does API checks, then calls either the tunnel or session setsockopt
1330 * handler, according to whether the PPPoL2TP socket is a for a regular
1331 * session or the special tunnel type.
1332 */
1333 static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
1334 char __user *optval, unsigned int optlen)
1335 {
1336 struct sock *sk = sock->sk;
1337 struct l2tp_session *session;
1338 struct l2tp_tunnel *tunnel;
1339 struct pppol2tp_session *ps;
1340 int val;
1341 int err;
1342
1343 if (level != SOL_PPPOL2TP)
1344 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1345
1346 if (optlen < sizeof(int))
1347 return -EINVAL;
1348
1349 if (get_user(val, (int __user *)optval))
1350 return -EFAULT;
1351
1352 err = -ENOTCONN;
1353 if (sk->sk_user_data == NULL)
1354 goto end;
1355
1356 /* Get session context from the socket */
1357 err = -EBADF;
1358 session = pppol2tp_sock_to_session(sk);
1359 if (session == NULL)
1360 goto end;
1361
1362 /* Special case: if session_id == 0x0000, treat as operation on tunnel
1363 */
1364 ps = l2tp_session_priv(session);
1365 if ((session->session_id == 0) &&
1366 (session->peer_session_id == 0)) {
1367 err = -EBADF;
1368 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1369 if (tunnel == NULL)
1370 goto end_put_sess;
1371
1372 err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
1373 sock_put(ps->tunnel_sock);
1374 } else
1375 err = pppol2tp_session_setsockopt(sk, session, optname, val);
1376
1377 err = 0;
1378
1379 end_put_sess:
1380 sock_put(sk);
1381 end:
1382 return err;
1383 }
1384
1385 /* Tunnel getsockopt helper. Called with sock locked.
1386 */
1387 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
1388 struct l2tp_tunnel *tunnel,
1389 int optname, int *val)
1390 {
1391 int err = 0;
1392
1393 switch (optname) {
1394 case PPPOL2TP_SO_DEBUG:
1395 *val = tunnel->debug;
1396 PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1397 "%s: get debug=%x\n", tunnel->name, tunnel->debug);
1398 break;
1399
1400 default:
1401 err = -ENOPROTOOPT;
1402 break;
1403 }
1404
1405 return err;
1406 }
1407
1408 /* Session getsockopt helper. Called with sock locked.
1409 */
1410 static int pppol2tp_session_getsockopt(struct sock *sk,
1411 struct l2tp_session *session,
1412 int optname, int *val)
1413 {
1414 int err = 0;
1415
1416 switch (optname) {
1417 case PPPOL2TP_SO_RECVSEQ:
1418 *val = session->recv_seq;
1419 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1420 "%s: get recv_seq=%d\n", session->name, *val);
1421 break;
1422
1423 case PPPOL2TP_SO_SENDSEQ:
1424 *val = session->send_seq;
1425 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1426 "%s: get send_seq=%d\n", session->name, *val);
1427 break;
1428
1429 case PPPOL2TP_SO_LNSMODE:
1430 *val = session->lns_mode;
1431 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1432 "%s: get lns_mode=%d\n", session->name, *val);
1433 break;
1434
1435 case PPPOL2TP_SO_DEBUG:
1436 *val = session->debug;
1437 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1438 "%s: get debug=%d\n", session->name, *val);
1439 break;
1440
1441 case PPPOL2TP_SO_REORDERTO:
1442 *val = (int) jiffies_to_msecs(session->reorder_timeout);
1443 PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
1444 "%s: get reorder_timeout=%d\n", session->name, *val);
1445 break;
1446
1447 default:
1448 err = -ENOPROTOOPT;
1449 }
1450
1451 return err;
1452 }
1453
1454 /* Main getsockopt() entry point.
1455 * Does API checks, then calls either the tunnel or session getsockopt
1456 * handler, according to whether the PPPoX socket is a for a regular session
1457 * or the special tunnel type.
1458 */
1459 static int pppol2tp_getsockopt(struct socket *sock, int level,
1460 int optname, char __user *optval, int __user *optlen)
1461 {
1462 struct sock *sk = sock->sk;
1463 struct l2tp_session *session;
1464 struct l2tp_tunnel *tunnel;
1465 int val, len;
1466 int err;
1467 struct pppol2tp_session *ps;
1468
1469 if (level != SOL_PPPOL2TP)
1470 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1471
1472 if (get_user(len, (int __user *) optlen))
1473 return -EFAULT;
1474
1475 len = min_t(unsigned int, len, sizeof(int));
1476
1477 if (len < 0)
1478 return -EINVAL;
1479
1480 err = -ENOTCONN;
1481 if (sk->sk_user_data == NULL)
1482 goto end;
1483
1484 /* Get the session context */
1485 err = -EBADF;
1486 session = pppol2tp_sock_to_session(sk);
1487 if (session == NULL)
1488 goto end;
1489
1490 /* Special case: if session_id == 0x0000, treat as operation on tunnel */
1491 ps = l2tp_session_priv(session);
1492 if ((session->session_id == 0) &&
1493 (session->peer_session_id == 0)) {
1494 err = -EBADF;
1495 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1496 if (tunnel == NULL)
1497 goto end_put_sess;
1498
1499 err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
1500 sock_put(ps->tunnel_sock);
1501 } else
1502 err = pppol2tp_session_getsockopt(sk, session, optname, &val);
1503
1504 err = -EFAULT;
1505 if (put_user(len, (int __user *) optlen))
1506 goto end_put_sess;
1507
1508 if (copy_to_user((void __user *) optval, &val, len))
1509 goto end_put_sess;
1510
1511 err = 0;
1512
1513 end_put_sess:
1514 sock_put(sk);
1515 end:
1516 return err;
1517 }
1518
1519 /*****************************************************************************
1520 * /proc filesystem for debug
1521 * Since the original pppol2tp driver provided /proc/net/pppol2tp for
1522 * L2TPv2, we dump only L2TPv2 tunnels and sessions here.
1523 *****************************************************************************/
1524
1525 static unsigned int pppol2tp_net_id;
1526
1527 #ifdef CONFIG_PROC_FS
1528
1529 struct pppol2tp_seq_data {
1530 struct seq_net_private p;
1531 int tunnel_idx; /* current tunnel */
1532 int session_idx; /* index of session within current tunnel */
1533 struct l2tp_tunnel *tunnel;
1534 struct l2tp_session *session; /* NULL means get next tunnel */
1535 };
1536
1537 static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd)
1538 {
1539 for (;;) {
1540 pd->tunnel = l2tp_tunnel_find_nth(net, pd->tunnel_idx);
1541 pd->tunnel_idx++;
1542
1543 if (pd->tunnel == NULL)
1544 break;
1545
1546 /* Ignore L2TPv3 tunnels */
1547 if (pd->tunnel->version < 3)
1548 break;
1549 }
1550 }
1551
1552 static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd)
1553 {
1554 pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx);
1555 pd->session_idx++;
1556
1557 if (pd->session == NULL) {
1558 pd->session_idx = 0;
1559 pppol2tp_next_tunnel(net, pd);
1560 }
1561 }
1562
1563 static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
1564 {
1565 struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
1566 loff_t pos = *offs;
1567 struct net *net;
1568
1569 if (!pos)
1570 goto out;
1571
1572 BUG_ON(m->private == NULL);
1573 pd = m->private;
1574 net = seq_file_net(m);
1575
1576 if (pd->tunnel == NULL)
1577 pppol2tp_next_tunnel(net, pd);
1578 else
1579 pppol2tp_next_session(net, pd);
1580
1581 /* NULL tunnel and session indicates end of list */
1582 if ((pd->tunnel == NULL) && (pd->session == NULL))
1583 pd = NULL;
1584
1585 out:
1586 return pd;
1587 }
1588
1589 static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
1590 {
1591 (*pos)++;
1592 return NULL;
1593 }
1594
1595 static void pppol2tp_seq_stop(struct seq_file *p, void *v)
1596 {
1597 /* nothing to do */
1598 }
1599
1600 static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
1601 {
1602 struct l2tp_tunnel *tunnel = v;
1603
1604 seq_printf(m, "\nTUNNEL '%s', %c %d\n",
1605 tunnel->name,
1606 (tunnel == tunnel->sock->sk_user_data) ? 'Y' : 'N',
1607 atomic_read(&tunnel->ref_count) - 1);
1608 seq_printf(m, " %08x %llu/%llu/%llu %llu/%llu/%llu\n",
1609 tunnel->debug,
1610 (unsigned long long)tunnel->stats.tx_packets,
1611 (unsigned long long)tunnel->stats.tx_bytes,
1612 (unsigned long long)tunnel->stats.tx_errors,
1613 (unsigned long long)tunnel->stats.rx_packets,
1614 (unsigned long long)tunnel->stats.rx_bytes,
1615 (unsigned long long)tunnel->stats.rx_errors);
1616 }
1617
1618 static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
1619 {
1620 struct l2tp_session *session = v;
1621 struct l2tp_tunnel *tunnel = session->tunnel;
1622 struct pppol2tp_session *ps = l2tp_session_priv(session);
1623 struct pppox_sock *po = pppox_sk(ps->sock);
1624 u32 ip = 0;
1625 u16 port = 0;
1626
1627 if (tunnel->sock) {
1628 struct inet_sock *inet = inet_sk(tunnel->sock);
1629 ip = ntohl(inet->inet_saddr);
1630 port = ntohs(inet->inet_sport);
1631 }
1632
1633 seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
1634 "%04X/%04X %d %c\n",
1635 session->name, ip, port,
1636 tunnel->tunnel_id,
1637 session->session_id,
1638 tunnel->peer_tunnel_id,
1639 session->peer_session_id,
1640 ps->sock->sk_state,
1641 (session == ps->sock->sk_user_data) ?
1642 'Y' : 'N');
1643 seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n",
1644 session->mtu, session->mru,
1645 session->recv_seq ? 'R' : '-',
1646 session->send_seq ? 'S' : '-',
1647 session->lns_mode ? "LNS" : "LAC",
1648 session->debug,
1649 jiffies_to_msecs(session->reorder_timeout));
1650 seq_printf(m, " %hu/%hu %llu/%llu/%llu %llu/%llu/%llu\n",
1651 session->nr, session->ns,
1652 (unsigned long long)session->stats.tx_packets,
1653 (unsigned long long)session->stats.tx_bytes,
1654 (unsigned long long)session->stats.tx_errors,
1655 (unsigned long long)session->stats.rx_packets,
1656 (unsigned long long)session->stats.rx_bytes,
1657 (unsigned long long)session->stats.rx_errors);
1658
1659 if (po)
1660 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
1661 }
1662
1663 static int pppol2tp_seq_show(struct seq_file *m, void *v)
1664 {
1665 struct pppol2tp_seq_data *pd = v;
1666
1667 /* display header on line 1 */
1668 if (v == SEQ_START_TOKEN) {
1669 seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
1670 seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
1671 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1672 seq_puts(m, " SESSION name, addr/port src-tid/sid "
1673 "dest-tid/sid state user-data-ok\n");
1674 seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
1675 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1676 goto out;
1677 }
1678
1679 /* Show the tunnel or session context.
1680 */
1681 if (pd->session == NULL)
1682 pppol2tp_seq_tunnel_show(m, pd->tunnel);
1683 else
1684 pppol2tp_seq_session_show(m, pd->session);
1685
1686 out:
1687 return 0;
1688 }
1689
1690 static const struct seq_operations pppol2tp_seq_ops = {
1691 .start = pppol2tp_seq_start,
1692 .next = pppol2tp_seq_next,
1693 .stop = pppol2tp_seq_stop,
1694 .show = pppol2tp_seq_show,
1695 };
1696
1697 /* Called when our /proc file is opened. We allocate data for use when
1698 * iterating our tunnel / session contexts and store it in the private
1699 * data of the seq_file.
1700 */
1701 static int pppol2tp_proc_open(struct inode *inode, struct file *file)
1702 {
1703 return seq_open_net(inode, file, &pppol2tp_seq_ops,
1704 sizeof(struct pppol2tp_seq_data));
1705 }
1706
1707 static const struct file_operations pppol2tp_proc_fops = {
1708 .owner = THIS_MODULE,
1709 .open = pppol2tp_proc_open,
1710 .read = seq_read,
1711 .llseek = seq_lseek,
1712 .release = seq_release_net,
1713 };
1714
1715 #endif /* CONFIG_PROC_FS */
1716
1717 /*****************************************************************************
1718 * Network namespace
1719 *****************************************************************************/
1720
1721 static __net_init int pppol2tp_init_net(struct net *net)
1722 {
1723 struct proc_dir_entry *pde;
1724 int err = 0;
1725
1726 pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops);
1727 if (!pde) {
1728 err = -ENOMEM;
1729 goto out;
1730 }
1731
1732 out:
1733 return err;
1734 }
1735
1736 static __net_exit void pppol2tp_exit_net(struct net *net)
1737 {
1738 proc_net_remove(net, "pppol2tp");
1739 }
1740
1741 static struct pernet_operations pppol2tp_net_ops = {
1742 .init = pppol2tp_init_net,
1743 .exit = pppol2tp_exit_net,
1744 .id = &pppol2tp_net_id,
1745 };
1746
1747 /*****************************************************************************
1748 * Init and cleanup
1749 *****************************************************************************/
1750
1751 static const struct proto_ops pppol2tp_ops = {
1752 .family = AF_PPPOX,
1753 .owner = THIS_MODULE,
1754 .release = pppol2tp_release,
1755 .bind = sock_no_bind,
1756 .connect = pppol2tp_connect,
1757 .socketpair = sock_no_socketpair,
1758 .accept = sock_no_accept,
1759 .getname = pppol2tp_getname,
1760 .poll = datagram_poll,
1761 .listen = sock_no_listen,
1762 .shutdown = sock_no_shutdown,
1763 .setsockopt = pppol2tp_setsockopt,
1764 .getsockopt = pppol2tp_getsockopt,
1765 .sendmsg = pppol2tp_sendmsg,
1766 .recvmsg = pppol2tp_recvmsg,
1767 .mmap = sock_no_mmap,
1768 .ioctl = pppox_ioctl,
1769 };
1770
1771 static const struct pppox_proto pppol2tp_proto = {
1772 .create = pppol2tp_create,
1773 .ioctl = pppol2tp_ioctl
1774 };
1775
1776 #ifdef CONFIG_L2TP_V3
1777
1778 static const struct l2tp_nl_cmd_ops pppol2tp_nl_cmd_ops = {
1779 .session_create = pppol2tp_session_create,
1780 .session_delete = pppol2tp_session_delete,
1781 };
1782
1783 #endif /* CONFIG_L2TP_V3 */
1784
1785 static int __init pppol2tp_init(void)
1786 {
1787 int err;
1788
1789 err = register_pernet_device(&pppol2tp_net_ops);
1790 if (err)
1791 goto out;
1792
1793 err = proto_register(&pppol2tp_sk_proto, 0);
1794 if (err)
1795 goto out_unregister_pppol2tp_pernet;
1796
1797 err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
1798 if (err)
1799 goto out_unregister_pppol2tp_proto;
1800
1801 #ifdef CONFIG_L2TP_V3
1802 err = l2tp_nl_register_ops(L2TP_PWTYPE_PPP, &pppol2tp_nl_cmd_ops);
1803 if (err)
1804 goto out_unregister_pppox;
1805 #endif
1806
1807 printk(KERN_INFO "PPPoL2TP kernel driver, %s\n",
1808 PPPOL2TP_DRV_VERSION);
1809
1810 out:
1811 return err;
1812
1813 #ifdef CONFIG_L2TP_V3
1814 out_unregister_pppox:
1815 unregister_pppox_proto(PX_PROTO_OL2TP);
1816 #endif
1817 out_unregister_pppol2tp_proto:
1818 proto_unregister(&pppol2tp_sk_proto);
1819 out_unregister_pppol2tp_pernet:
1820 unregister_pernet_device(&pppol2tp_net_ops);
1821 goto out;
1822 }
1823
1824 static void __exit pppol2tp_exit(void)
1825 {
1826 #ifdef CONFIG_L2TP_V3
1827 l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
1828 #endif
1829 unregister_pppox_proto(PX_PROTO_OL2TP);
1830 proto_unregister(&pppol2tp_sk_proto);
1831 unregister_pernet_device(&pppol2tp_net_ops);
1832 }
1833
1834 module_init(pppol2tp_init);
1835 module_exit(pppol2tp_exit);
1836
1837 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1838 MODULE_DESCRIPTION("PPP over L2TP over UDP");
1839 MODULE_LICENSE("GPL");
1840 MODULE_VERSION(PPPOL2TP_DRV_VERSION);