Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
61
62 #include <linux/module.h>
63 #include <linux/string.h>
64 #include <linux/list.h>
65 #include <linux/uaccess.h>
66
67 #include <linux/kernel.h>
68 #include <linux/spinlock.h>
69 #include <linux/kthread.h>
70 #include <linux/sched.h>
71 #include <linux/slab.h>
72 #include <linux/errno.h>
73 #include <linux/jiffies.h>
74
75 #include <linux/netdevice.h>
76 #include <linux/net.h>
77 #include <linux/inetdevice.h>
78 #include <linux/skbuff.h>
79 #include <linux/init.h>
80 #include <linux/ip.h>
81 #include <linux/udp.h>
82 #include <linux/if_pppox.h>
83 #include <linux/if_pppol2tp.h>
84 #include <net/sock.h>
85 #include <linux/ppp_channel.h>
86 #include <linux/ppp_defs.h>
87 #include <linux/ppp-ioctl.h>
88 #include <linux/file.h>
89 #include <linux/hash.h>
90 #include <linux/sort.h>
91 #include <linux/proc_fs.h>
92 #include <linux/l2tp.h>
93 #include <linux/nsproxy.h>
94 #include <net/net_namespace.h>
95 #include <net/netns/generic.h>
96 #include <net/dst.h>
97 #include <net/ip.h>
98 #include <net/udp.h>
99 #include <net/xfrm.h>
100
101 #include <asm/byteorder.h>
102 #include <linux/atomic.h>
103
104 #include "l2tp_core.h"
105
106 #define PPPOL2TP_DRV_VERSION "V2.0"
107
108 /* Space for UDP, L2TP and PPP headers */
109 #define PPPOL2TP_HEADER_OVERHEAD 40
110
111 /* Number of bytes to build transmit L2TP headers.
112 * Unfortunately the size is different depending on whether sequence numbers
113 * are enabled.
114 */
115 #define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10
116 #define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6
117
118 /* Private data of each session. This data lives at the end of struct
119 * l2tp_session, referenced via session->priv[].
120 */
121 struct pppol2tp_session {
122 int owner; /* pid that opened the socket */
123
124 struct sock *sock; /* Pointer to the session
125 * PPPoX socket */
126 struct sock *tunnel_sock; /* Pointer to the tunnel UDP
127 * socket */
128 int flags; /* accessed by PPPIOCGFLAGS.
129 * Unused. */
130 };
131
132 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb);
133
134 static const struct ppp_channel_ops pppol2tp_chan_ops = {
135 .start_xmit = pppol2tp_xmit,
136 };
137
138 static const struct proto_ops pppol2tp_ops;
139
140 /* Helpers to obtain tunnel/session contexts from sockets.
141 */
142 static inline struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk)
143 {
144 struct l2tp_session *session;
145
146 if (sk == NULL)
147 return NULL;
148
149 sock_hold(sk);
150 session = (struct l2tp_session *)(sk->sk_user_data);
151 if (session == NULL) {
152 sock_put(sk);
153 goto out;
154 }
155
156 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
157
158 out:
159 return session;
160 }
161
162 /*****************************************************************************
163 * Receive data handling
164 *****************************************************************************/
165
166 static int pppol2tp_recv_payload_hook(struct sk_buff *skb)
167 {
168 /* Skip PPP header, if present. In testing, Microsoft L2TP clients
169 * don't send the PPP header (PPP header compression enabled), but
170 * other clients can include the header. So we cope with both cases
171 * here. The PPP header is always FF03 when using L2TP.
172 *
173 * Note that skb->data[] isn't dereferenced from a u16 ptr here since
174 * the field may be unaligned.
175 */
176 if (!pskb_may_pull(skb, 2))
177 return 1;
178
179 if ((skb->data[0] == 0xff) && (skb->data[1] == 0x03))
180 skb_pull(skb, 2);
181
182 return 0;
183 }
184
185 /* Receive message. This is the recvmsg for the PPPoL2TP socket.
186 */
187 static int pppol2tp_recvmsg(struct kiocb *iocb, struct socket *sock,
188 struct msghdr *msg, size_t len,
189 int flags)
190 {
191 int err;
192 struct sk_buff *skb;
193 struct sock *sk = sock->sk;
194
195 err = -EIO;
196 if (sk->sk_state & PPPOX_BOUND)
197 goto end;
198
199 msg->msg_namelen = 0;
200
201 err = 0;
202 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
203 flags & MSG_DONTWAIT, &err);
204 if (!skb)
205 goto end;
206
207 if (len > skb->len)
208 len = skb->len;
209 else if (len < skb->len)
210 msg->msg_flags |= MSG_TRUNC;
211
212 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
213 if (likely(err == 0))
214 err = len;
215
216 kfree_skb(skb);
217 end:
218 return err;
219 }
220
221 static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
222 {
223 struct pppol2tp_session *ps = l2tp_session_priv(session);
224 struct sock *sk = NULL;
225
226 /* If the socket is bound, send it in to PPP's input queue. Otherwise
227 * queue it on the session socket.
228 */
229 sk = ps->sock;
230 if (sk == NULL)
231 goto no_sock;
232
233 if (sk->sk_state & PPPOX_BOUND) {
234 struct pppox_sock *po;
235 l2tp_dbg(session, PPPOL2TP_MSG_DATA,
236 "%s: recv %d byte data frame, passing to ppp\n",
237 session->name, data_len);
238
239 /* We need to forget all info related to the L2TP packet
240 * gathered in the skb as we are going to reuse the same
241 * skb for the inner packet.
242 * Namely we need to:
243 * - reset xfrm (IPSec) information as it applies to
244 * the outer L2TP packet and not to the inner one
245 * - release the dst to force a route lookup on the inner
246 * IP packet since skb->dst currently points to the dst
247 * of the UDP tunnel
248 * - reset netfilter information as it doesn't apply
249 * to the inner packet either
250 */
251 secpath_reset(skb);
252 skb_dst_drop(skb);
253 nf_reset(skb);
254
255 po = pppox_sk(sk);
256 ppp_input(&po->chan, skb);
257 } else {
258 l2tp_info(session, PPPOL2TP_MSG_DATA, "%s: socket not bound\n",
259 session->name);
260
261 /* Not bound. Nothing we can do, so discard. */
262 session->stats.rx_errors++;
263 kfree_skb(skb);
264 }
265
266 return;
267
268 no_sock:
269 l2tp_info(session, PPPOL2TP_MSG_DATA, "%s: no socket\n", session->name);
270 kfree_skb(skb);
271 }
272
273 static void pppol2tp_session_sock_hold(struct l2tp_session *session)
274 {
275 struct pppol2tp_session *ps = l2tp_session_priv(session);
276
277 if (ps->sock)
278 sock_hold(ps->sock);
279 }
280
281 static void pppol2tp_session_sock_put(struct l2tp_session *session)
282 {
283 struct pppol2tp_session *ps = l2tp_session_priv(session);
284
285 if (ps->sock)
286 sock_put(ps->sock);
287 }
288
289 /************************************************************************
290 * Transmit handling
291 ***********************************************************************/
292
293 /* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
294 * when a user application does a sendmsg() on the session socket. L2TP and
295 * PPP headers must be inserted into the user's data.
296 */
297 static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
298 size_t total_len)
299 {
300 static const unsigned char ppph[2] = { 0xff, 0x03 };
301 struct sock *sk = sock->sk;
302 struct sk_buff *skb;
303 int error;
304 struct l2tp_session *session;
305 struct l2tp_tunnel *tunnel;
306 struct pppol2tp_session *ps;
307 int uhlen;
308
309 error = -ENOTCONN;
310 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
311 goto error;
312
313 /* Get session and tunnel contexts */
314 error = -EBADF;
315 session = pppol2tp_sock_to_session(sk);
316 if (session == NULL)
317 goto error;
318
319 ps = l2tp_session_priv(session);
320 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
321 if (tunnel == NULL)
322 goto error_put_sess;
323
324 uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
325
326 /* Allocate a socket buffer */
327 error = -ENOMEM;
328 skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) +
329 uhlen + session->hdr_len +
330 sizeof(ppph) + total_len,
331 0, GFP_KERNEL);
332 if (!skb)
333 goto error_put_sess_tun;
334
335 /* Reserve space for headers. */
336 skb_reserve(skb, NET_SKB_PAD);
337 skb_reset_network_header(skb);
338 skb_reserve(skb, sizeof(struct iphdr));
339 skb_reset_transport_header(skb);
340 skb_reserve(skb, uhlen);
341
342 /* Add PPP header */
343 skb->data[0] = ppph[0];
344 skb->data[1] = ppph[1];
345 skb_put(skb, 2);
346
347 /* Copy user data into skb */
348 error = memcpy_fromiovec(skb->data, m->msg_iov, total_len);
349 if (error < 0) {
350 kfree_skb(skb);
351 goto error_put_sess_tun;
352 }
353 skb_put(skb, total_len);
354
355 l2tp_xmit_skb(session, skb, session->hdr_len);
356
357 sock_put(ps->tunnel_sock);
358
359 return error;
360
361 error_put_sess_tun:
362 sock_put(ps->tunnel_sock);
363 error_put_sess:
364 sock_put(sk);
365 error:
366 return error;
367 }
368
369 /* Transmit function called by generic PPP driver. Sends PPP frame
370 * over PPPoL2TP socket.
371 *
372 * This is almost the same as pppol2tp_sendmsg(), but rather than
373 * being called with a msghdr from userspace, it is called with a skb
374 * from the kernel.
375 *
376 * The supplied skb from ppp doesn't have enough headroom for the
377 * insertion of L2TP, UDP and IP headers so we need to allocate more
378 * headroom in the skb. This will create a cloned skb. But we must be
379 * careful in the error case because the caller will expect to free
380 * the skb it supplied, not our cloned skb. So we take care to always
381 * leave the original skb unfreed if we return an error.
382 */
383 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
384 {
385 static const u8 ppph[2] = { 0xff, 0x03 };
386 struct sock *sk = (struct sock *) chan->private;
387 struct sock *sk_tun;
388 struct l2tp_session *session;
389 struct l2tp_tunnel *tunnel;
390 struct pppol2tp_session *ps;
391 int old_headroom;
392 int new_headroom;
393 int uhlen, headroom;
394
395 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
396 goto abort;
397
398 /* Get session and tunnel contexts from the socket */
399 session = pppol2tp_sock_to_session(sk);
400 if (session == NULL)
401 goto abort;
402
403 ps = l2tp_session_priv(session);
404 sk_tun = ps->tunnel_sock;
405 if (sk_tun == NULL)
406 goto abort_put_sess;
407 tunnel = l2tp_sock_to_tunnel(sk_tun);
408 if (tunnel == NULL)
409 goto abort_put_sess;
410
411 old_headroom = skb_headroom(skb);
412 uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
413 headroom = NET_SKB_PAD +
414 sizeof(struct iphdr) + /* IP header */
415 uhlen + /* UDP header (if L2TP_ENCAPTYPE_UDP) */
416 session->hdr_len + /* L2TP header */
417 sizeof(ppph); /* PPP header */
418 if (skb_cow_head(skb, headroom))
419 goto abort_put_sess_tun;
420
421 new_headroom = skb_headroom(skb);
422 skb->truesize += new_headroom - old_headroom;
423
424 /* Setup PPP header */
425 __skb_push(skb, sizeof(ppph));
426 skb->data[0] = ppph[0];
427 skb->data[1] = ppph[1];
428
429 l2tp_xmit_skb(session, skb, session->hdr_len);
430
431 sock_put(sk_tun);
432 sock_put(sk);
433 return 1;
434
435 abort_put_sess_tun:
436 sock_put(sk_tun);
437 abort_put_sess:
438 sock_put(sk);
439 abort:
440 /* Free the original skb */
441 kfree_skb(skb);
442 return 1;
443 }
444
445 /*****************************************************************************
446 * Session (and tunnel control) socket create/destroy.
447 *****************************************************************************/
448
449 /* Called by l2tp_core when a session socket is being closed.
450 */
451 static void pppol2tp_session_close(struct l2tp_session *session)
452 {
453 struct pppol2tp_session *ps = l2tp_session_priv(session);
454 struct sock *sk = ps->sock;
455 struct sk_buff *skb;
456
457 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
458
459 if (session->session_id == 0)
460 goto out;
461
462 if (sk != NULL) {
463 lock_sock(sk);
464
465 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
466 pppox_unbind_sock(sk);
467 sk->sk_state = PPPOX_DEAD;
468 sk->sk_state_change(sk);
469 }
470
471 /* Purge any queued data */
472 skb_queue_purge(&sk->sk_receive_queue);
473 skb_queue_purge(&sk->sk_write_queue);
474 while ((skb = skb_dequeue(&session->reorder_q))) {
475 kfree_skb(skb);
476 sock_put(sk);
477 }
478
479 release_sock(sk);
480 }
481
482 out:
483 return;
484 }
485
486 /* Really kill the session socket. (Called from sock_put() if
487 * refcnt == 0.)
488 */
489 static void pppol2tp_session_destruct(struct sock *sk)
490 {
491 struct l2tp_session *session;
492
493 if (sk->sk_user_data != NULL) {
494 session = sk->sk_user_data;
495 if (session == NULL)
496 goto out;
497
498 sk->sk_user_data = NULL;
499 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
500 l2tp_session_dec_refcount(session);
501 }
502
503 out:
504 return;
505 }
506
507 /* Called when the PPPoX socket (session) is closed.
508 */
509 static int pppol2tp_release(struct socket *sock)
510 {
511 struct sock *sk = sock->sk;
512 struct l2tp_session *session;
513 int error;
514
515 if (!sk)
516 return 0;
517
518 error = -EBADF;
519 lock_sock(sk);
520 if (sock_flag(sk, SOCK_DEAD) != 0)
521 goto error;
522
523 pppox_unbind_sock(sk);
524
525 /* Signal the death of the socket. */
526 sk->sk_state = PPPOX_DEAD;
527 sock_orphan(sk);
528 sock->sk = NULL;
529
530 session = pppol2tp_sock_to_session(sk);
531
532 /* Purge any queued data */
533 skb_queue_purge(&sk->sk_receive_queue);
534 skb_queue_purge(&sk->sk_write_queue);
535 if (session != NULL) {
536 struct sk_buff *skb;
537 while ((skb = skb_dequeue(&session->reorder_q))) {
538 kfree_skb(skb);
539 sock_put(sk);
540 }
541 sock_put(sk);
542 }
543
544 release_sock(sk);
545
546 /* This will delete the session context via
547 * pppol2tp_session_destruct() if the socket's refcnt drops to
548 * zero.
549 */
550 sock_put(sk);
551
552 return 0;
553
554 error:
555 release_sock(sk);
556 return error;
557 }
558
559 static struct proto pppol2tp_sk_proto = {
560 .name = "PPPOL2TP",
561 .owner = THIS_MODULE,
562 .obj_size = sizeof(struct pppox_sock),
563 };
564
565 static int pppol2tp_backlog_recv(struct sock *sk, struct sk_buff *skb)
566 {
567 int rc;
568
569 rc = l2tp_udp_encap_recv(sk, skb);
570 if (rc)
571 kfree_skb(skb);
572
573 return NET_RX_SUCCESS;
574 }
575
576 /* socket() handler. Initialize a new struct sock.
577 */
578 static int pppol2tp_create(struct net *net, struct socket *sock)
579 {
580 int error = -ENOMEM;
581 struct sock *sk;
582
583 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto);
584 if (!sk)
585 goto out;
586
587 sock_init_data(sock, sk);
588
589 sock->state = SS_UNCONNECTED;
590 sock->ops = &pppol2tp_ops;
591
592 sk->sk_backlog_rcv = pppol2tp_backlog_recv;
593 sk->sk_protocol = PX_PROTO_OL2TP;
594 sk->sk_family = PF_PPPOX;
595 sk->sk_state = PPPOX_NONE;
596 sk->sk_type = SOCK_STREAM;
597 sk->sk_destruct = pppol2tp_session_destruct;
598
599 error = 0;
600
601 out:
602 return error;
603 }
604
605 #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
606 static void pppol2tp_show(struct seq_file *m, void *arg)
607 {
608 struct l2tp_session *session = arg;
609 struct pppol2tp_session *ps = l2tp_session_priv(session);
610
611 if (ps) {
612 struct pppox_sock *po = pppox_sk(ps->sock);
613 if (po)
614 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
615 }
616 }
617 #endif
618
619 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
620 */
621 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
622 int sockaddr_len, int flags)
623 {
624 struct sock *sk = sock->sk;
625 struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
626 struct pppox_sock *po = pppox_sk(sk);
627 struct l2tp_session *session = NULL;
628 struct l2tp_tunnel *tunnel;
629 struct pppol2tp_session *ps;
630 struct dst_entry *dst;
631 struct l2tp_session_cfg cfg = { 0, };
632 int error = 0;
633 u32 tunnel_id, peer_tunnel_id;
634 u32 session_id, peer_session_id;
635 int ver = 2;
636 int fd;
637
638 lock_sock(sk);
639
640 error = -EINVAL;
641 if (sp->sa_protocol != PX_PROTO_OL2TP)
642 goto end;
643
644 /* Check for already bound sockets */
645 error = -EBUSY;
646 if (sk->sk_state & PPPOX_CONNECTED)
647 goto end;
648
649 /* We don't supporting rebinding anyway */
650 error = -EALREADY;
651 if (sk->sk_user_data)
652 goto end; /* socket is already attached */
653
654 /* Get params from socket address. Handle L2TPv2 and L2TPv3.
655 * This is nasty because there are different sockaddr_pppol2tp
656 * structs for L2TPv2, L2TPv3, over IPv4 and IPv6. We use
657 * the sockaddr size to determine which structure the caller
658 * is using.
659 */
660 peer_tunnel_id = 0;
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 struct sockaddr_pppol2tpv3 *sp3 =
669 (struct sockaddr_pppol2tpv3 *) sp;
670 ver = 3;
671 fd = sp3->pppol2tp.fd;
672 tunnel_id = sp3->pppol2tp.s_tunnel;
673 peer_tunnel_id = sp3->pppol2tp.d_tunnel;
674 session_id = sp3->pppol2tp.s_session;
675 peer_session_id = sp3->pppol2tp.d_session;
676 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpin6)) {
677 struct sockaddr_pppol2tpin6 *sp6 =
678 (struct sockaddr_pppol2tpin6 *) sp;
679 fd = sp6->pppol2tp.fd;
680 tunnel_id = sp6->pppol2tp.s_tunnel;
681 peer_tunnel_id = sp6->pppol2tp.d_tunnel;
682 session_id = sp6->pppol2tp.s_session;
683 peer_session_id = sp6->pppol2tp.d_session;
684 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3in6)) {
685 struct sockaddr_pppol2tpv3in6 *sp6 =
686 (struct sockaddr_pppol2tpv3in6 *) sp;
687 ver = 3;
688 fd = sp6->pppol2tp.fd;
689 tunnel_id = sp6->pppol2tp.s_tunnel;
690 peer_tunnel_id = sp6->pppol2tp.d_tunnel;
691 session_id = sp6->pppol2tp.s_session;
692 peer_session_id = sp6->pppol2tp.d_session;
693 } else {
694 error = -EINVAL;
695 goto end; /* bad socket address */
696 }
697
698 /* Don't bind if tunnel_id is 0 */
699 error = -EINVAL;
700 if (tunnel_id == 0)
701 goto end;
702
703 tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id);
704
705 /* Special case: create tunnel context if session_id and
706 * peer_session_id is 0. Otherwise look up tunnel using supplied
707 * tunnel id.
708 */
709 if ((session_id == 0) && (peer_session_id == 0)) {
710 if (tunnel == NULL) {
711 struct l2tp_tunnel_cfg tcfg = {
712 .encap = L2TP_ENCAPTYPE_UDP,
713 .debug = 0,
714 };
715 error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, &tcfg, &tunnel);
716 if (error < 0)
717 goto end;
718 }
719 } else {
720 /* Error if we can't find the tunnel */
721 error = -ENOENT;
722 if (tunnel == NULL)
723 goto end;
724
725 /* Error if socket is not prepped */
726 if (tunnel->sock == NULL)
727 goto end;
728 }
729
730 if (tunnel->recv_payload_hook == NULL)
731 tunnel->recv_payload_hook = pppol2tp_recv_payload_hook;
732
733 if (tunnel->peer_tunnel_id == 0)
734 tunnel->peer_tunnel_id = peer_tunnel_id;
735
736 /* Create session if it doesn't already exist. We handle the
737 * case where a session was previously created by the netlink
738 * interface by checking that the session doesn't already have
739 * a socket and its tunnel socket are what we expect. If any
740 * of those checks fail, return EEXIST to the caller.
741 */
742 session = l2tp_session_find(sock_net(sk), tunnel, session_id);
743 if (session == NULL) {
744 /* Default MTU must allow space for UDP/L2TP/PPP
745 * headers.
746 */
747 cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
748
749 /* Allocate and initialize a new session context. */
750 session = l2tp_session_create(sizeof(struct pppol2tp_session),
751 tunnel, session_id,
752 peer_session_id, &cfg);
753 if (session == NULL) {
754 error = -ENOMEM;
755 goto end;
756 }
757 } else {
758 ps = l2tp_session_priv(session);
759 error = -EEXIST;
760 if (ps->sock != NULL)
761 goto end;
762
763 /* consistency checks */
764 if (ps->tunnel_sock != tunnel->sock)
765 goto end;
766 }
767
768 /* Associate session with its PPPoL2TP socket */
769 ps = l2tp_session_priv(session);
770 ps->owner = current->pid;
771 ps->sock = sk;
772 ps->tunnel_sock = tunnel->sock;
773
774 session->recv_skb = pppol2tp_recv;
775 session->session_close = pppol2tp_session_close;
776 #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
777 session->show = pppol2tp_show;
778 #endif
779
780 /* We need to know each time a skb is dropped from the reorder
781 * queue.
782 */
783 session->ref = pppol2tp_session_sock_hold;
784 session->deref = pppol2tp_session_sock_put;
785
786 /* If PMTU discovery was enabled, use the MTU that was discovered */
787 dst = sk_dst_get(sk);
788 if (dst != NULL) {
789 u32 pmtu = dst_mtu(__sk_dst_get(sk));
790 if (pmtu != 0)
791 session->mtu = session->mru = pmtu -
792 PPPOL2TP_HEADER_OVERHEAD;
793 dst_release(dst);
794 }
795
796 /* Special case: if source & dest session_id == 0x0000, this
797 * socket is being created to manage the tunnel. Just set up
798 * the internal context for use by ioctl() and sockopt()
799 * handlers.
800 */
801 if ((session->session_id == 0) &&
802 (session->peer_session_id == 0)) {
803 error = 0;
804 goto out_no_ppp;
805 }
806
807 /* The only header we need to worry about is the L2TP
808 * header. This size is different depending on whether
809 * sequence numbers are enabled for the data channel.
810 */
811 po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
812
813 po->chan.private = sk;
814 po->chan.ops = &pppol2tp_chan_ops;
815 po->chan.mtu = session->mtu;
816
817 error = ppp_register_net_channel(sock_net(sk), &po->chan);
818 if (error)
819 goto end;
820
821 out_no_ppp:
822 /* This is how we get the session context from the socket. */
823 sk->sk_user_data = session;
824 sk->sk_state = PPPOX_CONNECTED;
825 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: created\n",
826 session->name);
827
828 end:
829 release_sock(sk);
830
831 return error;
832 }
833
834 #ifdef CONFIG_L2TP_V3
835
836 /* Called when creating sessions via the netlink interface.
837 */
838 static int pppol2tp_session_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
839 {
840 int error;
841 struct l2tp_tunnel *tunnel;
842 struct l2tp_session *session;
843 struct pppol2tp_session *ps;
844
845 tunnel = l2tp_tunnel_find(net, tunnel_id);
846
847 /* Error if we can't find the tunnel */
848 error = -ENOENT;
849 if (tunnel == NULL)
850 goto out;
851
852 /* Error if tunnel socket is not prepped */
853 if (tunnel->sock == NULL)
854 goto out;
855
856 /* Check that this session doesn't already exist */
857 error = -EEXIST;
858 session = l2tp_session_find(net, tunnel, session_id);
859 if (session != NULL)
860 goto out;
861
862 /* Default MTU values. */
863 if (cfg->mtu == 0)
864 cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
865 if (cfg->mru == 0)
866 cfg->mru = cfg->mtu;
867
868 /* Allocate and initialize a new session context. */
869 error = -ENOMEM;
870 session = l2tp_session_create(sizeof(struct pppol2tp_session),
871 tunnel, session_id,
872 peer_session_id, cfg);
873 if (session == NULL)
874 goto out;
875
876 ps = l2tp_session_priv(session);
877 ps->tunnel_sock = tunnel->sock;
878
879 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: created\n",
880 session->name);
881
882 error = 0;
883
884 out:
885 return error;
886 }
887
888 /* Called when deleting sessions via the netlink interface.
889 */
890 static int pppol2tp_session_delete(struct l2tp_session *session)
891 {
892 struct pppol2tp_session *ps = l2tp_session_priv(session);
893
894 if (ps->sock == NULL)
895 l2tp_session_dec_refcount(session);
896
897 return 0;
898 }
899
900 #endif /* CONFIG_L2TP_V3 */
901
902 /* getname() support.
903 */
904 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
905 int *usockaddr_len, int peer)
906 {
907 int len = 0;
908 int error = 0;
909 struct l2tp_session *session;
910 struct l2tp_tunnel *tunnel;
911 struct sock *sk = sock->sk;
912 struct inet_sock *inet;
913 struct pppol2tp_session *pls;
914
915 error = -ENOTCONN;
916 if (sk == NULL)
917 goto end;
918 if (sk->sk_state != PPPOX_CONNECTED)
919 goto end;
920
921 error = -EBADF;
922 session = pppol2tp_sock_to_session(sk);
923 if (session == NULL)
924 goto end;
925
926 pls = l2tp_session_priv(session);
927 tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock);
928 if (tunnel == NULL) {
929 error = -EBADF;
930 goto end_put_sess;
931 }
932
933 inet = inet_sk(tunnel->sock);
934 if ((tunnel->version == 2) && (tunnel->sock->sk_family == AF_INET)) {
935 struct sockaddr_pppol2tp sp;
936 len = sizeof(sp);
937 memset(&sp, 0, len);
938 sp.sa_family = AF_PPPOX;
939 sp.sa_protocol = PX_PROTO_OL2TP;
940 sp.pppol2tp.fd = tunnel->fd;
941 sp.pppol2tp.pid = pls->owner;
942 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
943 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
944 sp.pppol2tp.s_session = session->session_id;
945 sp.pppol2tp.d_session = session->peer_session_id;
946 sp.pppol2tp.addr.sin_family = AF_INET;
947 sp.pppol2tp.addr.sin_port = inet->inet_dport;
948 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
949 memcpy(uaddr, &sp, len);
950 #if IS_ENABLED(CONFIG_IPV6)
951 } else if ((tunnel->version == 2) &&
952 (tunnel->sock->sk_family == AF_INET6)) {
953 struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
954 struct sockaddr_pppol2tpin6 sp;
955 len = sizeof(sp);
956 memset(&sp, 0, len);
957 sp.sa_family = AF_PPPOX;
958 sp.sa_protocol = PX_PROTO_OL2TP;
959 sp.pppol2tp.fd = tunnel->fd;
960 sp.pppol2tp.pid = pls->owner;
961 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
962 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
963 sp.pppol2tp.s_session = session->session_id;
964 sp.pppol2tp.d_session = session->peer_session_id;
965 sp.pppol2tp.addr.sin6_family = AF_INET6;
966 sp.pppol2tp.addr.sin6_port = inet->inet_dport;
967 memcpy(&sp.pppol2tp.addr.sin6_addr, &np->daddr,
968 sizeof(np->daddr));
969 memcpy(uaddr, &sp, len);
970 } else if ((tunnel->version == 3) &&
971 (tunnel->sock->sk_family == AF_INET6)) {
972 struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
973 struct sockaddr_pppol2tpv3in6 sp;
974 len = sizeof(sp);
975 memset(&sp, 0, len);
976 sp.sa_family = AF_PPPOX;
977 sp.sa_protocol = PX_PROTO_OL2TP;
978 sp.pppol2tp.fd = tunnel->fd;
979 sp.pppol2tp.pid = pls->owner;
980 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
981 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
982 sp.pppol2tp.s_session = session->session_id;
983 sp.pppol2tp.d_session = session->peer_session_id;
984 sp.pppol2tp.addr.sin6_family = AF_INET6;
985 sp.pppol2tp.addr.sin6_port = inet->inet_dport;
986 memcpy(&sp.pppol2tp.addr.sin6_addr, &np->daddr,
987 sizeof(np->daddr));
988 memcpy(uaddr, &sp, len);
989 #endif
990 } else if (tunnel->version == 3) {
991 struct sockaddr_pppol2tpv3 sp;
992 len = sizeof(sp);
993 memset(&sp, 0, len);
994 sp.sa_family = AF_PPPOX;
995 sp.sa_protocol = PX_PROTO_OL2TP;
996 sp.pppol2tp.fd = tunnel->fd;
997 sp.pppol2tp.pid = pls->owner;
998 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
999 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
1000 sp.pppol2tp.s_session = session->session_id;
1001 sp.pppol2tp.d_session = session->peer_session_id;
1002 sp.pppol2tp.addr.sin_family = AF_INET;
1003 sp.pppol2tp.addr.sin_port = inet->inet_dport;
1004 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
1005 memcpy(uaddr, &sp, len);
1006 }
1007
1008 *usockaddr_len = len;
1009
1010 sock_put(pls->tunnel_sock);
1011 end_put_sess:
1012 sock_put(sk);
1013 error = 0;
1014
1015 end:
1016 return error;
1017 }
1018
1019 /****************************************************************************
1020 * ioctl() handlers.
1021 *
1022 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1023 * sockets. However, in order to control kernel tunnel features, we allow
1024 * userspace to create a special "tunnel" PPPoX socket which is used for
1025 * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
1026 * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
1027 * calls.
1028 ****************************************************************************/
1029
1030 static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest,
1031 struct l2tp_stats *stats)
1032 {
1033 dest->tx_packets = stats->tx_packets;
1034 dest->tx_bytes = stats->tx_bytes;
1035 dest->tx_errors = stats->tx_errors;
1036 dest->rx_packets = stats->rx_packets;
1037 dest->rx_bytes = stats->rx_bytes;
1038 dest->rx_seq_discards = stats->rx_seq_discards;
1039 dest->rx_oos_packets = stats->rx_oos_packets;
1040 dest->rx_errors = stats->rx_errors;
1041 }
1042
1043 /* Session ioctl helper.
1044 */
1045 static int pppol2tp_session_ioctl(struct l2tp_session *session,
1046 unsigned int cmd, unsigned long arg)
1047 {
1048 struct ifreq ifr;
1049 int err = 0;
1050 struct sock *sk;
1051 int val = (int) arg;
1052 struct pppol2tp_session *ps = l2tp_session_priv(session);
1053 struct l2tp_tunnel *tunnel = session->tunnel;
1054 struct pppol2tp_ioc_stats stats;
1055
1056 l2tp_dbg(session, PPPOL2TP_MSG_CONTROL,
1057 "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n",
1058 session->name, cmd, arg);
1059
1060 sk = ps->sock;
1061 sock_hold(sk);
1062
1063 switch (cmd) {
1064 case SIOCGIFMTU:
1065 err = -ENXIO;
1066 if (!(sk->sk_state & PPPOX_CONNECTED))
1067 break;
1068
1069 err = -EFAULT;
1070 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1071 break;
1072 ifr.ifr_mtu = session->mtu;
1073 if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq)))
1074 break;
1075
1076 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get mtu=%d\n",
1077 session->name, session->mtu);
1078 err = 0;
1079 break;
1080
1081 case SIOCSIFMTU:
1082 err = -ENXIO;
1083 if (!(sk->sk_state & PPPOX_CONNECTED))
1084 break;
1085
1086 err = -EFAULT;
1087 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1088 break;
1089
1090 session->mtu = ifr.ifr_mtu;
1091
1092 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set mtu=%d\n",
1093 session->name, session->mtu);
1094 err = 0;
1095 break;
1096
1097 case PPPIOCGMRU:
1098 err = -ENXIO;
1099 if (!(sk->sk_state & PPPOX_CONNECTED))
1100 break;
1101
1102 err = -EFAULT;
1103 if (put_user(session->mru, (int __user *) arg))
1104 break;
1105
1106 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get mru=%d\n",
1107 session->name, session->mru);
1108 err = 0;
1109 break;
1110
1111 case PPPIOCSMRU:
1112 err = -ENXIO;
1113 if (!(sk->sk_state & PPPOX_CONNECTED))
1114 break;
1115
1116 err = -EFAULT;
1117 if (get_user(val, (int __user *) arg))
1118 break;
1119
1120 session->mru = val;
1121 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set mru=%d\n",
1122 session->name, session->mru);
1123 err = 0;
1124 break;
1125
1126 case PPPIOCGFLAGS:
1127 err = -EFAULT;
1128 if (put_user(ps->flags, (int __user *) arg))
1129 break;
1130
1131 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get flags=%d\n",
1132 session->name, ps->flags);
1133 err = 0;
1134 break;
1135
1136 case PPPIOCSFLAGS:
1137 err = -EFAULT;
1138 if (get_user(val, (int __user *) arg))
1139 break;
1140 ps->flags = val;
1141 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set flags=%d\n",
1142 session->name, ps->flags);
1143 err = 0;
1144 break;
1145
1146 case PPPIOCGL2TPSTATS:
1147 err = -ENXIO;
1148 if (!(sk->sk_state & PPPOX_CONNECTED))
1149 break;
1150
1151 memset(&stats, 0, sizeof(stats));
1152 stats.tunnel_id = tunnel->tunnel_id;
1153 stats.session_id = session->session_id;
1154 pppol2tp_copy_stats(&stats, &session->stats);
1155 if (copy_to_user((void __user *) arg, &stats,
1156 sizeof(stats)))
1157 break;
1158 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get L2TP stats\n",
1159 session->name);
1160 err = 0;
1161 break;
1162
1163 default:
1164 err = -ENOSYS;
1165 break;
1166 }
1167
1168 sock_put(sk);
1169
1170 return err;
1171 }
1172
1173 /* Tunnel ioctl helper.
1174 *
1175 * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data
1176 * specifies a session_id, the session ioctl handler is called. This allows an
1177 * application to retrieve session stats via a tunnel socket.
1178 */
1179 static int pppol2tp_tunnel_ioctl(struct l2tp_tunnel *tunnel,
1180 unsigned int cmd, unsigned long arg)
1181 {
1182 int err = 0;
1183 struct sock *sk;
1184 struct pppol2tp_ioc_stats stats;
1185
1186 l2tp_dbg(tunnel, PPPOL2TP_MSG_CONTROL,
1187 "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n",
1188 tunnel->name, cmd, arg);
1189
1190 sk = tunnel->sock;
1191 sock_hold(sk);
1192
1193 switch (cmd) {
1194 case PPPIOCGL2TPSTATS:
1195 err = -ENXIO;
1196 if (!(sk->sk_state & PPPOX_CONNECTED))
1197 break;
1198
1199 if (copy_from_user(&stats, (void __user *) arg,
1200 sizeof(stats))) {
1201 err = -EFAULT;
1202 break;
1203 }
1204 if (stats.session_id != 0) {
1205 /* resend to session ioctl handler */
1206 struct l2tp_session *session =
1207 l2tp_session_find(sock_net(sk), tunnel, stats.session_id);
1208 if (session != NULL)
1209 err = pppol2tp_session_ioctl(session, cmd, arg);
1210 else
1211 err = -EBADR;
1212 break;
1213 }
1214 #ifdef CONFIG_XFRM
1215 stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0;
1216 #endif
1217 pppol2tp_copy_stats(&stats, &tunnel->stats);
1218 if (copy_to_user((void __user *) arg, &stats, sizeof(stats))) {
1219 err = -EFAULT;
1220 break;
1221 }
1222 l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: get L2TP stats\n",
1223 tunnel->name);
1224 err = 0;
1225 break;
1226
1227 default:
1228 err = -ENOSYS;
1229 break;
1230 }
1231
1232 sock_put(sk);
1233
1234 return err;
1235 }
1236
1237 /* Main ioctl() handler.
1238 * Dispatch to tunnel or session helpers depending on the socket.
1239 */
1240 static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
1241 unsigned long arg)
1242 {
1243 struct sock *sk = sock->sk;
1244 struct l2tp_session *session;
1245 struct l2tp_tunnel *tunnel;
1246 struct pppol2tp_session *ps;
1247 int err;
1248
1249 if (!sk)
1250 return 0;
1251
1252 err = -EBADF;
1253 if (sock_flag(sk, SOCK_DEAD) != 0)
1254 goto end;
1255
1256 err = -ENOTCONN;
1257 if ((sk->sk_user_data == NULL) ||
1258 (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND))))
1259 goto end;
1260
1261 /* Get session context from the socket */
1262 err = -EBADF;
1263 session = pppol2tp_sock_to_session(sk);
1264 if (session == NULL)
1265 goto end;
1266
1267 /* Special case: if session's session_id is zero, treat ioctl as a
1268 * tunnel ioctl
1269 */
1270 ps = l2tp_session_priv(session);
1271 if ((session->session_id == 0) &&
1272 (session->peer_session_id == 0)) {
1273 err = -EBADF;
1274 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1275 if (tunnel == NULL)
1276 goto end_put_sess;
1277
1278 err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
1279 sock_put(ps->tunnel_sock);
1280 goto end_put_sess;
1281 }
1282
1283 err = pppol2tp_session_ioctl(session, cmd, arg);
1284
1285 end_put_sess:
1286 sock_put(sk);
1287 end:
1288 return err;
1289 }
1290
1291 /*****************************************************************************
1292 * setsockopt() / getsockopt() support.
1293 *
1294 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1295 * sockets. In order to control kernel tunnel features, we allow userspace to
1296 * create a special "tunnel" PPPoX socket which is used for control only.
1297 * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
1298 * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
1299 *****************************************************************************/
1300
1301 /* Tunnel setsockopt() helper.
1302 */
1303 static int pppol2tp_tunnel_setsockopt(struct sock *sk,
1304 struct l2tp_tunnel *tunnel,
1305 int optname, int val)
1306 {
1307 int err = 0;
1308
1309 switch (optname) {
1310 case PPPOL2TP_SO_DEBUG:
1311 tunnel->debug = val;
1312 l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: set debug=%x\n",
1313 tunnel->name, tunnel->debug);
1314 break;
1315
1316 default:
1317 err = -ENOPROTOOPT;
1318 break;
1319 }
1320
1321 return err;
1322 }
1323
1324 /* Session setsockopt helper.
1325 */
1326 static int pppol2tp_session_setsockopt(struct sock *sk,
1327 struct l2tp_session *session,
1328 int optname, int val)
1329 {
1330 int err = 0;
1331 struct pppol2tp_session *ps = l2tp_session_priv(session);
1332
1333 switch (optname) {
1334 case PPPOL2TP_SO_RECVSEQ:
1335 if ((val != 0) && (val != 1)) {
1336 err = -EINVAL;
1337 break;
1338 }
1339 session->recv_seq = val ? -1 : 0;
1340 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1341 "%s: set recv_seq=%d\n",
1342 session->name, session->recv_seq);
1343 break;
1344
1345 case PPPOL2TP_SO_SENDSEQ:
1346 if ((val != 0) && (val != 1)) {
1347 err = -EINVAL;
1348 break;
1349 }
1350 session->send_seq = val ? -1 : 0;
1351 {
1352 struct sock *ssk = ps->sock;
1353 struct pppox_sock *po = pppox_sk(ssk);
1354 po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
1355 PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
1356 }
1357 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1358 "%s: set send_seq=%d\n",
1359 session->name, session->send_seq);
1360 break;
1361
1362 case PPPOL2TP_SO_LNSMODE:
1363 if ((val != 0) && (val != 1)) {
1364 err = -EINVAL;
1365 break;
1366 }
1367 session->lns_mode = val ? -1 : 0;
1368 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1369 "%s: set lns_mode=%d\n",
1370 session->name, session->lns_mode);
1371 break;
1372
1373 case PPPOL2TP_SO_DEBUG:
1374 session->debug = val;
1375 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set debug=%x\n",
1376 session->name, session->debug);
1377 break;
1378
1379 case PPPOL2TP_SO_REORDERTO:
1380 session->reorder_timeout = msecs_to_jiffies(val);
1381 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1382 "%s: set reorder_timeout=%d\n",
1383 session->name, session->reorder_timeout);
1384 break;
1385
1386 default:
1387 err = -ENOPROTOOPT;
1388 break;
1389 }
1390
1391 return err;
1392 }
1393
1394 /* Main setsockopt() entry point.
1395 * Does API checks, then calls either the tunnel or session setsockopt
1396 * handler, according to whether the PPPoL2TP socket is a for a regular
1397 * session or the special tunnel type.
1398 */
1399 static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
1400 char __user *optval, unsigned int optlen)
1401 {
1402 struct sock *sk = sock->sk;
1403 struct l2tp_session *session;
1404 struct l2tp_tunnel *tunnel;
1405 struct pppol2tp_session *ps;
1406 int val;
1407 int err;
1408
1409 if (level != SOL_PPPOL2TP)
1410 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1411
1412 if (optlen < sizeof(int))
1413 return -EINVAL;
1414
1415 if (get_user(val, (int __user *)optval))
1416 return -EFAULT;
1417
1418 err = -ENOTCONN;
1419 if (sk->sk_user_data == NULL)
1420 goto end;
1421
1422 /* Get session context from the socket */
1423 err = -EBADF;
1424 session = pppol2tp_sock_to_session(sk);
1425 if (session == NULL)
1426 goto end;
1427
1428 /* Special case: if session_id == 0x0000, treat as operation on tunnel
1429 */
1430 ps = l2tp_session_priv(session);
1431 if ((session->session_id == 0) &&
1432 (session->peer_session_id == 0)) {
1433 err = -EBADF;
1434 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1435 if (tunnel == NULL)
1436 goto end_put_sess;
1437
1438 err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
1439 sock_put(ps->tunnel_sock);
1440 } else
1441 err = pppol2tp_session_setsockopt(sk, session, optname, val);
1442
1443 err = 0;
1444
1445 end_put_sess:
1446 sock_put(sk);
1447 end:
1448 return err;
1449 }
1450
1451 /* Tunnel getsockopt helper. Called with sock locked.
1452 */
1453 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
1454 struct l2tp_tunnel *tunnel,
1455 int optname, int *val)
1456 {
1457 int err = 0;
1458
1459 switch (optname) {
1460 case PPPOL2TP_SO_DEBUG:
1461 *val = tunnel->debug;
1462 l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: get debug=%x\n",
1463 tunnel->name, tunnel->debug);
1464 break;
1465
1466 default:
1467 err = -ENOPROTOOPT;
1468 break;
1469 }
1470
1471 return err;
1472 }
1473
1474 /* Session getsockopt helper. Called with sock locked.
1475 */
1476 static int pppol2tp_session_getsockopt(struct sock *sk,
1477 struct l2tp_session *session,
1478 int optname, int *val)
1479 {
1480 int err = 0;
1481
1482 switch (optname) {
1483 case PPPOL2TP_SO_RECVSEQ:
1484 *val = session->recv_seq;
1485 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1486 "%s: get recv_seq=%d\n", session->name, *val);
1487 break;
1488
1489 case PPPOL2TP_SO_SENDSEQ:
1490 *val = session->send_seq;
1491 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1492 "%s: get send_seq=%d\n", session->name, *val);
1493 break;
1494
1495 case PPPOL2TP_SO_LNSMODE:
1496 *val = session->lns_mode;
1497 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1498 "%s: get lns_mode=%d\n", session->name, *val);
1499 break;
1500
1501 case PPPOL2TP_SO_DEBUG:
1502 *val = session->debug;
1503 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get debug=%d\n",
1504 session->name, *val);
1505 break;
1506
1507 case PPPOL2TP_SO_REORDERTO:
1508 *val = (int) jiffies_to_msecs(session->reorder_timeout);
1509 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1510 "%s: get reorder_timeout=%d\n", session->name, *val);
1511 break;
1512
1513 default:
1514 err = -ENOPROTOOPT;
1515 }
1516
1517 return err;
1518 }
1519
1520 /* Main getsockopt() entry point.
1521 * Does API checks, then calls either the tunnel or session getsockopt
1522 * handler, according to whether the PPPoX socket is a for a regular session
1523 * or the special tunnel type.
1524 */
1525 static int pppol2tp_getsockopt(struct socket *sock, int level,
1526 int optname, char __user *optval, int __user *optlen)
1527 {
1528 struct sock *sk = sock->sk;
1529 struct l2tp_session *session;
1530 struct l2tp_tunnel *tunnel;
1531 int val, len;
1532 int err;
1533 struct pppol2tp_session *ps;
1534
1535 if (level != SOL_PPPOL2TP)
1536 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1537
1538 if (get_user(len, (int __user *) optlen))
1539 return -EFAULT;
1540
1541 len = min_t(unsigned int, len, sizeof(int));
1542
1543 if (len < 0)
1544 return -EINVAL;
1545
1546 err = -ENOTCONN;
1547 if (sk->sk_user_data == NULL)
1548 goto end;
1549
1550 /* Get the session context */
1551 err = -EBADF;
1552 session = pppol2tp_sock_to_session(sk);
1553 if (session == NULL)
1554 goto end;
1555
1556 /* Special case: if session_id == 0x0000, treat as operation on tunnel */
1557 ps = l2tp_session_priv(session);
1558 if ((session->session_id == 0) &&
1559 (session->peer_session_id == 0)) {
1560 err = -EBADF;
1561 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1562 if (tunnel == NULL)
1563 goto end_put_sess;
1564
1565 err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
1566 sock_put(ps->tunnel_sock);
1567 } else
1568 err = pppol2tp_session_getsockopt(sk, session, optname, &val);
1569
1570 err = -EFAULT;
1571 if (put_user(len, (int __user *) optlen))
1572 goto end_put_sess;
1573
1574 if (copy_to_user((void __user *) optval, &val, len))
1575 goto end_put_sess;
1576
1577 err = 0;
1578
1579 end_put_sess:
1580 sock_put(sk);
1581 end:
1582 return err;
1583 }
1584
1585 /*****************************************************************************
1586 * /proc filesystem for debug
1587 * Since the original pppol2tp driver provided /proc/net/pppol2tp for
1588 * L2TPv2, we dump only L2TPv2 tunnels and sessions here.
1589 *****************************************************************************/
1590
1591 static unsigned int pppol2tp_net_id;
1592
1593 #ifdef CONFIG_PROC_FS
1594
1595 struct pppol2tp_seq_data {
1596 struct seq_net_private p;
1597 int tunnel_idx; /* current tunnel */
1598 int session_idx; /* index of session within current tunnel */
1599 struct l2tp_tunnel *tunnel;
1600 struct l2tp_session *session; /* NULL means get next tunnel */
1601 };
1602
1603 static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd)
1604 {
1605 for (;;) {
1606 pd->tunnel = l2tp_tunnel_find_nth(net, pd->tunnel_idx);
1607 pd->tunnel_idx++;
1608
1609 if (pd->tunnel == NULL)
1610 break;
1611
1612 /* Ignore L2TPv3 tunnels */
1613 if (pd->tunnel->version < 3)
1614 break;
1615 }
1616 }
1617
1618 static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd)
1619 {
1620 pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx);
1621 pd->session_idx++;
1622
1623 if (pd->session == NULL) {
1624 pd->session_idx = 0;
1625 pppol2tp_next_tunnel(net, pd);
1626 }
1627 }
1628
1629 static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
1630 {
1631 struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
1632 loff_t pos = *offs;
1633 struct net *net;
1634
1635 if (!pos)
1636 goto out;
1637
1638 BUG_ON(m->private == NULL);
1639 pd = m->private;
1640 net = seq_file_net(m);
1641
1642 if (pd->tunnel == NULL)
1643 pppol2tp_next_tunnel(net, pd);
1644 else
1645 pppol2tp_next_session(net, pd);
1646
1647 /* NULL tunnel and session indicates end of list */
1648 if ((pd->tunnel == NULL) && (pd->session == NULL))
1649 pd = NULL;
1650
1651 out:
1652 return pd;
1653 }
1654
1655 static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
1656 {
1657 (*pos)++;
1658 return NULL;
1659 }
1660
1661 static void pppol2tp_seq_stop(struct seq_file *p, void *v)
1662 {
1663 /* nothing to do */
1664 }
1665
1666 static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
1667 {
1668 struct l2tp_tunnel *tunnel = v;
1669
1670 seq_printf(m, "\nTUNNEL '%s', %c %d\n",
1671 tunnel->name,
1672 (tunnel == tunnel->sock->sk_user_data) ? 'Y' : 'N',
1673 atomic_read(&tunnel->ref_count) - 1);
1674 seq_printf(m, " %08x %llu/%llu/%llu %llu/%llu/%llu\n",
1675 tunnel->debug,
1676 (unsigned long long)tunnel->stats.tx_packets,
1677 (unsigned long long)tunnel->stats.tx_bytes,
1678 (unsigned long long)tunnel->stats.tx_errors,
1679 (unsigned long long)tunnel->stats.rx_packets,
1680 (unsigned long long)tunnel->stats.rx_bytes,
1681 (unsigned long long)tunnel->stats.rx_errors);
1682 }
1683
1684 static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
1685 {
1686 struct l2tp_session *session = v;
1687 struct l2tp_tunnel *tunnel = session->tunnel;
1688 struct pppol2tp_session *ps = l2tp_session_priv(session);
1689 struct pppox_sock *po = pppox_sk(ps->sock);
1690 u32 ip = 0;
1691 u16 port = 0;
1692
1693 if (tunnel->sock) {
1694 struct inet_sock *inet = inet_sk(tunnel->sock);
1695 ip = ntohl(inet->inet_saddr);
1696 port = ntohs(inet->inet_sport);
1697 }
1698
1699 seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
1700 "%04X/%04X %d %c\n",
1701 session->name, ip, port,
1702 tunnel->tunnel_id,
1703 session->session_id,
1704 tunnel->peer_tunnel_id,
1705 session->peer_session_id,
1706 ps->sock->sk_state,
1707 (session == ps->sock->sk_user_data) ?
1708 'Y' : 'N');
1709 seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n",
1710 session->mtu, session->mru,
1711 session->recv_seq ? 'R' : '-',
1712 session->send_seq ? 'S' : '-',
1713 session->lns_mode ? "LNS" : "LAC",
1714 session->debug,
1715 jiffies_to_msecs(session->reorder_timeout));
1716 seq_printf(m, " %hu/%hu %llu/%llu/%llu %llu/%llu/%llu\n",
1717 session->nr, session->ns,
1718 (unsigned long long)session->stats.tx_packets,
1719 (unsigned long long)session->stats.tx_bytes,
1720 (unsigned long long)session->stats.tx_errors,
1721 (unsigned long long)session->stats.rx_packets,
1722 (unsigned long long)session->stats.rx_bytes,
1723 (unsigned long long)session->stats.rx_errors);
1724
1725 if (po)
1726 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
1727 }
1728
1729 static int pppol2tp_seq_show(struct seq_file *m, void *v)
1730 {
1731 struct pppol2tp_seq_data *pd = v;
1732
1733 /* display header on line 1 */
1734 if (v == SEQ_START_TOKEN) {
1735 seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
1736 seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
1737 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1738 seq_puts(m, " SESSION name, addr/port src-tid/sid "
1739 "dest-tid/sid state user-data-ok\n");
1740 seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
1741 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1742 goto out;
1743 }
1744
1745 /* Show the tunnel or session context.
1746 */
1747 if (pd->session == NULL)
1748 pppol2tp_seq_tunnel_show(m, pd->tunnel);
1749 else
1750 pppol2tp_seq_session_show(m, pd->session);
1751
1752 out:
1753 return 0;
1754 }
1755
1756 static const struct seq_operations pppol2tp_seq_ops = {
1757 .start = pppol2tp_seq_start,
1758 .next = pppol2tp_seq_next,
1759 .stop = pppol2tp_seq_stop,
1760 .show = pppol2tp_seq_show,
1761 };
1762
1763 /* Called when our /proc file is opened. We allocate data for use when
1764 * iterating our tunnel / session contexts and store it in the private
1765 * data of the seq_file.
1766 */
1767 static int pppol2tp_proc_open(struct inode *inode, struct file *file)
1768 {
1769 return seq_open_net(inode, file, &pppol2tp_seq_ops,
1770 sizeof(struct pppol2tp_seq_data));
1771 }
1772
1773 static const struct file_operations pppol2tp_proc_fops = {
1774 .owner = THIS_MODULE,
1775 .open = pppol2tp_proc_open,
1776 .read = seq_read,
1777 .llseek = seq_lseek,
1778 .release = seq_release_net,
1779 };
1780
1781 #endif /* CONFIG_PROC_FS */
1782
1783 /*****************************************************************************
1784 * Network namespace
1785 *****************************************************************************/
1786
1787 static __net_init int pppol2tp_init_net(struct net *net)
1788 {
1789 struct proc_dir_entry *pde;
1790 int err = 0;
1791
1792 pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops);
1793 if (!pde) {
1794 err = -ENOMEM;
1795 goto out;
1796 }
1797
1798 out:
1799 return err;
1800 }
1801
1802 static __net_exit void pppol2tp_exit_net(struct net *net)
1803 {
1804 proc_net_remove(net, "pppol2tp");
1805 }
1806
1807 static struct pernet_operations pppol2tp_net_ops = {
1808 .init = pppol2tp_init_net,
1809 .exit = pppol2tp_exit_net,
1810 .id = &pppol2tp_net_id,
1811 };
1812
1813 /*****************************************************************************
1814 * Init and cleanup
1815 *****************************************************************************/
1816
1817 static const struct proto_ops pppol2tp_ops = {
1818 .family = AF_PPPOX,
1819 .owner = THIS_MODULE,
1820 .release = pppol2tp_release,
1821 .bind = sock_no_bind,
1822 .connect = pppol2tp_connect,
1823 .socketpair = sock_no_socketpair,
1824 .accept = sock_no_accept,
1825 .getname = pppol2tp_getname,
1826 .poll = datagram_poll,
1827 .listen = sock_no_listen,
1828 .shutdown = sock_no_shutdown,
1829 .setsockopt = pppol2tp_setsockopt,
1830 .getsockopt = pppol2tp_getsockopt,
1831 .sendmsg = pppol2tp_sendmsg,
1832 .recvmsg = pppol2tp_recvmsg,
1833 .mmap = sock_no_mmap,
1834 .ioctl = pppox_ioctl,
1835 };
1836
1837 static const struct pppox_proto pppol2tp_proto = {
1838 .create = pppol2tp_create,
1839 .ioctl = pppol2tp_ioctl
1840 };
1841
1842 #ifdef CONFIG_L2TP_V3
1843
1844 static const struct l2tp_nl_cmd_ops pppol2tp_nl_cmd_ops = {
1845 .session_create = pppol2tp_session_create,
1846 .session_delete = pppol2tp_session_delete,
1847 };
1848
1849 #endif /* CONFIG_L2TP_V3 */
1850
1851 static int __init pppol2tp_init(void)
1852 {
1853 int err;
1854
1855 err = register_pernet_device(&pppol2tp_net_ops);
1856 if (err)
1857 goto out;
1858
1859 err = proto_register(&pppol2tp_sk_proto, 0);
1860 if (err)
1861 goto out_unregister_pppol2tp_pernet;
1862
1863 err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
1864 if (err)
1865 goto out_unregister_pppol2tp_proto;
1866
1867 #ifdef CONFIG_L2TP_V3
1868 err = l2tp_nl_register_ops(L2TP_PWTYPE_PPP, &pppol2tp_nl_cmd_ops);
1869 if (err)
1870 goto out_unregister_pppox;
1871 #endif
1872
1873 pr_info("PPPoL2TP kernel driver, %s\n", PPPOL2TP_DRV_VERSION);
1874
1875 out:
1876 return err;
1877
1878 #ifdef CONFIG_L2TP_V3
1879 out_unregister_pppox:
1880 unregister_pppox_proto(PX_PROTO_OL2TP);
1881 #endif
1882 out_unregister_pppol2tp_proto:
1883 proto_unregister(&pppol2tp_sk_proto);
1884 out_unregister_pppol2tp_pernet:
1885 unregister_pernet_device(&pppol2tp_net_ops);
1886 goto out;
1887 }
1888
1889 static void __exit pppol2tp_exit(void)
1890 {
1891 #ifdef CONFIG_L2TP_V3
1892 l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
1893 #endif
1894 unregister_pppox_proto(PX_PROTO_OL2TP);
1895 proto_unregister(&pppol2tp_sk_proto);
1896 unregister_pernet_device(&pppol2tp_net_ops);
1897 }
1898
1899 module_init(pppol2tp_init);
1900 module_exit(pppol2tp_exit);
1901
1902 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1903 MODULE_DESCRIPTION("PPP over L2TP over UDP");
1904 MODULE_LICENSE("GPL");
1905 MODULE_VERSION(PPPOL2TP_DRV_VERSION);
1906 MODULE_ALIAS("pppox-proto-" __stringify(PX_PROTO_OL2TP));