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Revert "ALSA: hda: Flush interrupts on disabling"
[linux/fpc-iii.git] / net / l2tp / l2tp_ppp.c
blob16b63e60396fbac4e9ada6d113900a13e369a65b
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 #include <net/inet_common.h>
101
102 #include <asm/byteorder.h>
103 #include <linux/atomic.h>
104
105 #include "l2tp_core.h"
106
107 #define PPPOL2TP_DRV_VERSION "V2.0"
108
109 /* Space for UDP, L2TP and PPP headers */
110 #define PPPOL2TP_HEADER_OVERHEAD 40
111
112 /* Number of bytes to build transmit L2TP headers.
113 * Unfortunately the size is different depending on whether sequence numbers
114 * are enabled.
115 */
116 #define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10
117 #define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6
118
119 /* Private data of each session. This data lives at the end of struct
120 * l2tp_session, referenced via session->priv[].
121 */
122 struct pppol2tp_session {
123 int owner; /* pid that opened the socket */
124
125 struct sock *sock; /* Pointer to the session
126 * PPPoX socket */
127 struct sock *tunnel_sock; /* Pointer to the tunnel UDP
128 * socket */
129 int flags; /* accessed by PPPIOCGFLAGS.
130 * Unused. */
131 };
132
133 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb);
134
135 static const struct ppp_channel_ops pppol2tp_chan_ops = {
136 .start_xmit = pppol2tp_xmit,
137 };
138
139 static const struct proto_ops pppol2tp_ops;
140
141 /* Helpers to obtain tunnel/session contexts from sockets.
142 */
143 static inline struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk)
144 {
145 struct l2tp_session *session;
146
147 if (sk == NULL)
148 return NULL;
149
150 sock_hold(sk);
151 session = (struct l2tp_session *)(sk->sk_user_data);
152 if (session == NULL) {
153 sock_put(sk);
154 goto out;
155 }
156
157 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
158
159 out:
160 return session;
161 }
162
163 /*****************************************************************************
164 * Receive data handling
165 *****************************************************************************/
166
167 static int pppol2tp_recv_payload_hook(struct sk_buff *skb)
168 {
169 /* Skip PPP header, if present. In testing, Microsoft L2TP clients
170 * don't send the PPP header (PPP header compression enabled), but
171 * other clients can include the header. So we cope with both cases
172 * here. The PPP header is always FF03 when using L2TP.
173 *
174 * Note that skb->data[] isn't dereferenced from a u16 ptr here since
175 * the field may be unaligned.
176 */
177 if (!pskb_may_pull(skb, 2))
178 return 1;
179
180 if ((skb->data[0] == PPP_ALLSTATIONS) && (skb->data[1] == PPP_UI))
181 skb_pull(skb, 2);
182
183 return 0;
184 }
185
186 /* Receive message. This is the recvmsg for the PPPoL2TP socket.
187 */
188 static int pppol2tp_recvmsg(struct socket *sock, struct msghdr *msg,
189 size_t len, 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 err = 0;
200 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
201 flags & MSG_DONTWAIT, &err);
202 if (!skb)
203 goto end;
204
205 if (len > skb->len)
206 len = skb->len;
207 else if (len < skb->len)
208 msg->msg_flags |= MSG_TRUNC;
209
210 err = skb_copy_datagram_msg(skb, 0, msg, len);
211 if (likely(err == 0))
212 err = len;
213
214 kfree_skb(skb);
215 end:
216 return err;
217 }
218
219 static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
220 {
221 struct pppol2tp_session *ps = l2tp_session_priv(session);
222 struct sock *sk = NULL;
223
224 /* If the socket is bound, send it in to PPP's input queue. Otherwise
225 * queue it on the session socket.
226 */
227 sk = ps->sock;
228 if (sk == NULL)
229 goto no_sock;
230
231 if (sk->sk_state & PPPOX_BOUND) {
232 struct pppox_sock *po;
233
234 l2tp_dbg(session, PPPOL2TP_MSG_DATA,
235 "%s: recv %d byte data frame, passing to ppp\n",
236 session->name, data_len);
237
238 po = pppox_sk(sk);
239 ppp_input(&po->chan, skb);
240 } else {
241 l2tp_dbg(session, PPPOL2TP_MSG_DATA,
242 "%s: recv %d byte data frame, passing to L2TP socket\n",
243 session->name, data_len);
244
245 if (sock_queue_rcv_skb(sk, skb) < 0) {
246 atomic_long_inc(&session->stats.rx_errors);
247 kfree_skb(skb);
248 }
249 }
250
251 return;
252
253 no_sock:
254 l2tp_info(session, PPPOL2TP_MSG_DATA, "%s: no socket\n", session->name);
255 kfree_skb(skb);
256 }
257
258 static void pppol2tp_session_sock_hold(struct l2tp_session *session)
259 {
260 struct pppol2tp_session *ps = l2tp_session_priv(session);
261
262 if (ps->sock)
263 sock_hold(ps->sock);
264 }
265
266 static void pppol2tp_session_sock_put(struct l2tp_session *session)
267 {
268 struct pppol2tp_session *ps = l2tp_session_priv(session);
269
270 if (ps->sock)
271 sock_put(ps->sock);
272 }
273
274 /************************************************************************
275 * Transmit handling
276 ***********************************************************************/
277
278 /* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
279 * when a user application does a sendmsg() on the session socket. L2TP and
280 * PPP headers must be inserted into the user's data.
281 */
282 static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
283 size_t total_len)
284 {
285 struct sock *sk = sock->sk;
286 struct sk_buff *skb;
287 int error;
288 struct l2tp_session *session;
289 struct l2tp_tunnel *tunnel;
290 struct pppol2tp_session *ps;
291 int uhlen;
292
293 error = -ENOTCONN;
294 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
295 goto error;
296
297 /* Get session and tunnel contexts */
298 error = -EBADF;
299 session = pppol2tp_sock_to_session(sk);
300 if (session == NULL)
301 goto error;
302
303 ps = l2tp_session_priv(session);
304 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
305 if (tunnel == NULL)
306 goto error_put_sess;
307
308 uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
309
310 /* Allocate a socket buffer */
311 error = -ENOMEM;
312 skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) +
313 uhlen + session->hdr_len +
314 2 + total_len, /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
315 0, GFP_KERNEL);
316 if (!skb)
317 goto error_put_sess_tun;
318
319 /* Reserve space for headers. */
320 skb_reserve(skb, NET_SKB_PAD);
321 skb_reset_network_header(skb);
322 skb_reserve(skb, sizeof(struct iphdr));
323 skb_reset_transport_header(skb);
324 skb_reserve(skb, uhlen);
325
326 /* Add PPP header */
327 skb->data[0] = PPP_ALLSTATIONS;
328 skb->data[1] = PPP_UI;
329 skb_put(skb, 2);
330
331 /* Copy user data into skb */
332 error = memcpy_from_msg(skb_put(skb, total_len), m, total_len);
333 if (error < 0) {
334 kfree_skb(skb);
335 goto error_put_sess_tun;
336 }
337
338 local_bh_disable();
339 l2tp_xmit_skb(session, skb, session->hdr_len);
340 local_bh_enable();
341
342 sock_put(ps->tunnel_sock);
343 sock_put(sk);
344
345 return total_len;
346
347 error_put_sess_tun:
348 sock_put(ps->tunnel_sock);
349 error_put_sess:
350 sock_put(sk);
351 error:
352 return error;
353 }
354
355 /* Transmit function called by generic PPP driver. Sends PPP frame
356 * over PPPoL2TP socket.
357 *
358 * This is almost the same as pppol2tp_sendmsg(), but rather than
359 * being called with a msghdr from userspace, it is called with a skb
360 * from the kernel.
361 *
362 * The supplied skb from ppp doesn't have enough headroom for the
363 * insertion of L2TP, UDP and IP headers so we need to allocate more
364 * headroom in the skb. This will create a cloned skb. But we must be
365 * careful in the error case because the caller will expect to free
366 * the skb it supplied, not our cloned skb. So we take care to always
367 * leave the original skb unfreed if we return an error.
368 */
369 static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
370 {
371 struct sock *sk = (struct sock *) chan->private;
372 struct sock *sk_tun;
373 struct l2tp_session *session;
374 struct l2tp_tunnel *tunnel;
375 struct pppol2tp_session *ps;
376 int uhlen, headroom;
377
378 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
379 goto abort;
380
381 /* Get session and tunnel contexts from the socket */
382 session = pppol2tp_sock_to_session(sk);
383 if (session == NULL)
384 goto abort;
385
386 ps = l2tp_session_priv(session);
387 sk_tun = ps->tunnel_sock;
388 if (sk_tun == NULL)
389 goto abort_put_sess;
390 tunnel = l2tp_sock_to_tunnel(sk_tun);
391 if (tunnel == NULL)
392 goto abort_put_sess;
393
394 uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
395 headroom = NET_SKB_PAD +
396 sizeof(struct iphdr) + /* IP header */
397 uhlen + /* UDP header (if L2TP_ENCAPTYPE_UDP) */
398 session->hdr_len + /* L2TP header */
399 2; /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
400 if (skb_cow_head(skb, headroom))
401 goto abort_put_sess_tun;
402
403 /* Setup PPP header */
404 __skb_push(skb, 2);
405 skb->data[0] = PPP_ALLSTATIONS;
406 skb->data[1] = PPP_UI;
407
408 local_bh_disable();
409 l2tp_xmit_skb(session, skb, session->hdr_len);
410 local_bh_enable();
411
412 sock_put(sk_tun);
413 sock_put(sk);
414 return 1;
415
416 abort_put_sess_tun:
417 sock_put(sk_tun);
418 abort_put_sess:
419 sock_put(sk);
420 abort:
421 /* Free the original skb */
422 kfree_skb(skb);
423 return 1;
424 }
425
426 /*****************************************************************************
427 * Session (and tunnel control) socket create/destroy.
428 *****************************************************************************/
429
430 /* Called by l2tp_core when a session socket is being closed.
431 */
432 static void pppol2tp_session_close(struct l2tp_session *session)
433 {
434 struct pppol2tp_session *ps = l2tp_session_priv(session);
435 struct sock *sk = ps->sock;
436 struct socket *sock = sk->sk_socket;
437
438 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
439
440 if (sock) {
441 inet_shutdown(sock, SEND_SHUTDOWN);
442 /* Don't let the session go away before our socket does */
443 l2tp_session_inc_refcount(session);
444 }
445 }
446
447 /* Really kill the session socket. (Called from sock_put() if
448 * refcnt == 0.)
449 */
450 static void pppol2tp_session_destruct(struct sock *sk)
451 {
452 struct l2tp_session *session = sk->sk_user_data;
453
454 skb_queue_purge(&sk->sk_receive_queue);
455 skb_queue_purge(&sk->sk_write_queue);
456
457 if (session) {
458 sk->sk_user_data = NULL;
459 BUG_ON(session->magic != L2TP_SESSION_MAGIC);
460 l2tp_session_dec_refcount(session);
461 }
462 }
463
464 /* Called when the PPPoX socket (session) is closed.
465 */
466 static int pppol2tp_release(struct socket *sock)
467 {
468 struct sock *sk = sock->sk;
469 struct l2tp_session *session;
470 int error;
471
472 if (!sk)
473 return 0;
474
475 error = -EBADF;
476 lock_sock(sk);
477 if (sock_flag(sk, SOCK_DEAD) != 0)
478 goto error;
479
480 pppox_unbind_sock(sk);
481
482 /* Signal the death of the socket. */
483 sk->sk_state = PPPOX_DEAD;
484 sock_orphan(sk);
485 sock->sk = NULL;
486
487 session = pppol2tp_sock_to_session(sk);
488
489 /* Purge any queued data */
490 if (session != NULL) {
491 __l2tp_session_unhash(session);
492 l2tp_session_queue_purge(session);
493 sock_put(sk);
494 }
495 release_sock(sk);
496
497 /* This will delete the session context via
498 * pppol2tp_session_destruct() if the socket's refcnt drops to
499 * zero.
500 */
501 sock_put(sk);
502
503 return 0;
504
505 error:
506 release_sock(sk);
507 return error;
508 }
509
510 static struct proto pppol2tp_sk_proto = {
511 .name = "PPPOL2TP",
512 .owner = THIS_MODULE,
513 .obj_size = sizeof(struct pppox_sock),
514 };
515
516 static int pppol2tp_backlog_recv(struct sock *sk, struct sk_buff *skb)
517 {
518 int rc;
519
520 rc = l2tp_udp_encap_recv(sk, skb);
521 if (rc)
522 kfree_skb(skb);
523
524 return NET_RX_SUCCESS;
525 }
526
527 /* socket() handler. Initialize a new struct sock.
528 */
529 static int pppol2tp_create(struct net *net, struct socket *sock, int kern)
530 {
531 int error = -ENOMEM;
532 struct sock *sk;
533
534 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto, kern);
535 if (!sk)
536 goto out;
537
538 sock_init_data(sock, sk);
539
540 sock->state = SS_UNCONNECTED;
541 sock->ops = &pppol2tp_ops;
542
543 sk->sk_backlog_rcv = pppol2tp_backlog_recv;
544 sk->sk_protocol = PX_PROTO_OL2TP;
545 sk->sk_family = PF_PPPOX;
546 sk->sk_state = PPPOX_NONE;
547 sk->sk_type = SOCK_STREAM;
548 sk->sk_destruct = pppol2tp_session_destruct;
549
550 error = 0;
551
552 out:
553 return error;
554 }
555
556 #if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
557 static void pppol2tp_show(struct seq_file *m, void *arg)
558 {
559 struct l2tp_session *session = arg;
560 struct pppol2tp_session *ps = l2tp_session_priv(session);
561
562 if (ps) {
563 struct pppox_sock *po = pppox_sk(ps->sock);
564 if (po)
565 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
566 }
567 }
568 #endif
569
570 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
571 */
572 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
573 int sockaddr_len, int flags)
574 {
575 struct sock *sk = sock->sk;
576 struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
577 struct pppox_sock *po = pppox_sk(sk);
578 struct l2tp_session *session = NULL;
579 struct l2tp_tunnel *tunnel;
580 struct pppol2tp_session *ps;
581 struct dst_entry *dst;
582 struct l2tp_session_cfg cfg = { 0, };
583 int error = 0;
584 u32 tunnel_id, peer_tunnel_id;
585 u32 session_id, peer_session_id;
586 bool drop_refcnt = false;
587 int ver = 2;
588 int fd;
589
590 lock_sock(sk);
591
592 error = -EINVAL;
593
594 if (sockaddr_len != sizeof(struct sockaddr_pppol2tp) &&
595 sockaddr_len != sizeof(struct sockaddr_pppol2tpv3) &&
596 sockaddr_len != sizeof(struct sockaddr_pppol2tpin6) &&
597 sockaddr_len != sizeof(struct sockaddr_pppol2tpv3in6))
598 goto end;
599
600 if (sp->sa_protocol != PX_PROTO_OL2TP)
601 goto end;
602
603 /* Check for already bound sockets */
604 error = -EBUSY;
605 if (sk->sk_state & PPPOX_CONNECTED)
606 goto end;
607
608 /* We don't supporting rebinding anyway */
609 error = -EALREADY;
610 if (sk->sk_user_data)
611 goto end; /* socket is already attached */
612
613 /* Get params from socket address. Handle L2TPv2 and L2TPv3.
614 * This is nasty because there are different sockaddr_pppol2tp
615 * structs for L2TPv2, L2TPv3, over IPv4 and IPv6. We use
616 * the sockaddr size to determine which structure the caller
617 * is using.
618 */
619 peer_tunnel_id = 0;
620 if (sockaddr_len == sizeof(struct sockaddr_pppol2tp)) {
621 fd = sp->pppol2tp.fd;
622 tunnel_id = sp->pppol2tp.s_tunnel;
623 peer_tunnel_id = sp->pppol2tp.d_tunnel;
624 session_id = sp->pppol2tp.s_session;
625 peer_session_id = sp->pppol2tp.d_session;
626 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3)) {
627 struct sockaddr_pppol2tpv3 *sp3 =
628 (struct sockaddr_pppol2tpv3 *) sp;
629 ver = 3;
630 fd = sp3->pppol2tp.fd;
631 tunnel_id = sp3->pppol2tp.s_tunnel;
632 peer_tunnel_id = sp3->pppol2tp.d_tunnel;
633 session_id = sp3->pppol2tp.s_session;
634 peer_session_id = sp3->pppol2tp.d_session;
635 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpin6)) {
636 struct sockaddr_pppol2tpin6 *sp6 =
637 (struct sockaddr_pppol2tpin6 *) sp;
638 fd = sp6->pppol2tp.fd;
639 tunnel_id = sp6->pppol2tp.s_tunnel;
640 peer_tunnel_id = sp6->pppol2tp.d_tunnel;
641 session_id = sp6->pppol2tp.s_session;
642 peer_session_id = sp6->pppol2tp.d_session;
643 } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3in6)) {
644 struct sockaddr_pppol2tpv3in6 *sp6 =
645 (struct sockaddr_pppol2tpv3in6 *) sp;
646 ver = 3;
647 fd = sp6->pppol2tp.fd;
648 tunnel_id = sp6->pppol2tp.s_tunnel;
649 peer_tunnel_id = sp6->pppol2tp.d_tunnel;
650 session_id = sp6->pppol2tp.s_session;
651 peer_session_id = sp6->pppol2tp.d_session;
652 } else {
653 error = -EINVAL;
654 goto end; /* bad socket address */
655 }
656
657 /* Don't bind if tunnel_id is 0 */
658 error = -EINVAL;
659 if (tunnel_id == 0)
660 goto end;
661
662 tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id);
663
664 /* Special case: create tunnel context if session_id and
665 * peer_session_id is 0. Otherwise look up tunnel using supplied
666 * tunnel id.
667 */
668 if ((session_id == 0) && (peer_session_id == 0)) {
669 if (tunnel == NULL) {
670 struct l2tp_tunnel_cfg tcfg = {
671 .encap = L2TP_ENCAPTYPE_UDP,
672 .debug = 0,
673 };
674 error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, &tcfg, &tunnel);
675 if (error < 0)
676 goto end;
677 }
678 } else {
679 /* Error if we can't find the tunnel */
680 error = -ENOENT;
681 if (tunnel == NULL)
682 goto end;
683
684 /* Error if socket is not prepped */
685 if (tunnel->sock == NULL)
686 goto end;
687 }
688
689 if (tunnel->recv_payload_hook == NULL)
690 tunnel->recv_payload_hook = pppol2tp_recv_payload_hook;
691
692 if (tunnel->peer_tunnel_id == 0)
693 tunnel->peer_tunnel_id = peer_tunnel_id;
694
695 session = l2tp_session_get(sock_net(sk), tunnel, session_id, false);
696 if (session) {
697 drop_refcnt = true;
698 ps = l2tp_session_priv(session);
699
700 /* Using a pre-existing session is fine as long as it hasn't
701 * been connected yet.
702 */
703 if (ps->sock) {
704 error = -EEXIST;
705 goto end;
706 }
707
708 /* consistency checks */
709 if (ps->tunnel_sock != tunnel->sock) {
710 error = -EEXIST;
711 goto end;
712 }
713 } else {
714 /* Default MTU must allow space for UDP/L2TP/PPP headers */
715 cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
716 cfg.mru = cfg.mtu;
717
718 session = l2tp_session_create(sizeof(struct pppol2tp_session),
719 tunnel, session_id,
720 peer_session_id, &cfg);
721 if (IS_ERR(session)) {
722 error = PTR_ERR(session);
723 goto end;
724 }
725 }
726
727 /* Associate session with its PPPoL2TP socket */
728 ps = l2tp_session_priv(session);
729 ps->owner = current->pid;
730 ps->sock = sk;
731 ps->tunnel_sock = tunnel->sock;
732
733 session->recv_skb = pppol2tp_recv;
734 session->session_close = pppol2tp_session_close;
735 #if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
736 session->show = pppol2tp_show;
737 #endif
738
739 /* We need to know each time a skb is dropped from the reorder
740 * queue.
741 */
742 session->ref = pppol2tp_session_sock_hold;
743 session->deref = pppol2tp_session_sock_put;
744
745 /* If PMTU discovery was enabled, use the MTU that was discovered */
746 dst = sk_dst_get(tunnel->sock);
747 if (dst != NULL) {
748 u32 pmtu = dst_mtu(dst);
749
750 if (pmtu != 0)
751 session->mtu = session->mru = pmtu -
752 PPPOL2TP_HEADER_OVERHEAD;
753 dst_release(dst);
754 }
755
756 /* Special case: if source & dest session_id == 0x0000, this
757 * socket is being created to manage the tunnel. Just set up
758 * the internal context for use by ioctl() and sockopt()
759 * handlers.
760 */
761 if ((session->session_id == 0) &&
762 (session->peer_session_id == 0)) {
763 error = 0;
764 goto out_no_ppp;
765 }
766
767 /* The only header we need to worry about is the L2TP
768 * header. This size is different depending on whether
769 * sequence numbers are enabled for the data channel.
770 */
771 po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
772
773 po->chan.private = sk;
774 po->chan.ops = &pppol2tp_chan_ops;
775 po->chan.mtu = session->mtu;
776
777 error = ppp_register_net_channel(sock_net(sk), &po->chan);
778 if (error)
779 goto end;
780
781 out_no_ppp:
782 /* This is how we get the session context from the socket. */
783 sk->sk_user_data = session;
784 sk->sk_state = PPPOX_CONNECTED;
785 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: created\n",
786 session->name);
787
788 end:
789 if (drop_refcnt)
790 l2tp_session_dec_refcount(session);
791 release_sock(sk);
792
793 return error;
794 }
795
796 #ifdef CONFIG_L2TP_V3
797
798 /* Called when creating sessions via the netlink interface.
799 */
800 static int pppol2tp_session_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
801 {
802 int error;
803 struct l2tp_tunnel *tunnel;
804 struct l2tp_session *session;
805 struct pppol2tp_session *ps;
806
807 tunnel = l2tp_tunnel_find(net, tunnel_id);
808
809 /* Error if we can't find the tunnel */
810 error = -ENOENT;
811 if (tunnel == NULL)
812 goto out;
813
814 /* Error if tunnel socket is not prepped */
815 if (tunnel->sock == NULL)
816 goto out;
817
818 /* Default MTU values. */
819 if (cfg->mtu == 0)
820 cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
821 if (cfg->mru == 0)
822 cfg->mru = cfg->mtu;
823
824 /* Allocate and initialize a new session context. */
825 session = l2tp_session_create(sizeof(struct pppol2tp_session),
826 tunnel, session_id,
827 peer_session_id, cfg);
828 if (IS_ERR(session)) {
829 error = PTR_ERR(session);
830 goto out;
831 }
832
833 ps = l2tp_session_priv(session);
834 ps->tunnel_sock = tunnel->sock;
835
836 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: created\n",
837 session->name);
838
839 error = 0;
840
841 out:
842 return error;
843 }
844
845 #endif /* CONFIG_L2TP_V3 */
846
847 /* getname() support.
848 */
849 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
850 int *usockaddr_len, int peer)
851 {
852 int len = 0;
853 int error = 0;
854 struct l2tp_session *session;
855 struct l2tp_tunnel *tunnel;
856 struct sock *sk = sock->sk;
857 struct inet_sock *inet;
858 struct pppol2tp_session *pls;
859
860 error = -ENOTCONN;
861 if (sk == NULL)
862 goto end;
863 if (!(sk->sk_state & PPPOX_CONNECTED))
864 goto end;
865
866 error = -EBADF;
867 session = pppol2tp_sock_to_session(sk);
868 if (session == NULL)
869 goto end;
870
871 pls = l2tp_session_priv(session);
872 tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock);
873 if (tunnel == NULL)
874 goto end_put_sess;
875
876 inet = inet_sk(tunnel->sock);
877 if ((tunnel->version == 2) && (tunnel->sock->sk_family == AF_INET)) {
878 struct sockaddr_pppol2tp sp;
879 len = sizeof(sp);
880 memset(&sp, 0, len);
881 sp.sa_family = AF_PPPOX;
882 sp.sa_protocol = PX_PROTO_OL2TP;
883 sp.pppol2tp.fd = tunnel->fd;
884 sp.pppol2tp.pid = pls->owner;
885 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
886 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
887 sp.pppol2tp.s_session = session->session_id;
888 sp.pppol2tp.d_session = session->peer_session_id;
889 sp.pppol2tp.addr.sin_family = AF_INET;
890 sp.pppol2tp.addr.sin_port = inet->inet_dport;
891 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
892 memcpy(uaddr, &sp, len);
893 #if IS_ENABLED(CONFIG_IPV6)
894 } else if ((tunnel->version == 2) &&
895 (tunnel->sock->sk_family == AF_INET6)) {
896 struct sockaddr_pppol2tpin6 sp;
897
898 len = sizeof(sp);
899 memset(&sp, 0, len);
900 sp.sa_family = AF_PPPOX;
901 sp.sa_protocol = PX_PROTO_OL2TP;
902 sp.pppol2tp.fd = tunnel->fd;
903 sp.pppol2tp.pid = pls->owner;
904 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
905 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
906 sp.pppol2tp.s_session = session->session_id;
907 sp.pppol2tp.d_session = session->peer_session_id;
908 sp.pppol2tp.addr.sin6_family = AF_INET6;
909 sp.pppol2tp.addr.sin6_port = inet->inet_dport;
910 memcpy(&sp.pppol2tp.addr.sin6_addr, &tunnel->sock->sk_v6_daddr,
911 sizeof(tunnel->sock->sk_v6_daddr));
912 memcpy(uaddr, &sp, len);
913 } else if ((tunnel->version == 3) &&
914 (tunnel->sock->sk_family == AF_INET6)) {
915 struct sockaddr_pppol2tpv3in6 sp;
916
917 len = sizeof(sp);
918 memset(&sp, 0, len);
919 sp.sa_family = AF_PPPOX;
920 sp.sa_protocol = PX_PROTO_OL2TP;
921 sp.pppol2tp.fd = tunnel->fd;
922 sp.pppol2tp.pid = pls->owner;
923 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
924 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
925 sp.pppol2tp.s_session = session->session_id;
926 sp.pppol2tp.d_session = session->peer_session_id;
927 sp.pppol2tp.addr.sin6_family = AF_INET6;
928 sp.pppol2tp.addr.sin6_port = inet->inet_dport;
929 memcpy(&sp.pppol2tp.addr.sin6_addr, &tunnel->sock->sk_v6_daddr,
930 sizeof(tunnel->sock->sk_v6_daddr));
931 memcpy(uaddr, &sp, len);
932 #endif
933 } else if (tunnel->version == 3) {
934 struct sockaddr_pppol2tpv3 sp;
935 len = sizeof(sp);
936 memset(&sp, 0, len);
937 sp.sa_family = AF_PPPOX;
938 sp.sa_protocol = PX_PROTO_OL2TP;
939 sp.pppol2tp.fd = tunnel->fd;
940 sp.pppol2tp.pid = pls->owner;
941 sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
942 sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
943 sp.pppol2tp.s_session = session->session_id;
944 sp.pppol2tp.d_session = session->peer_session_id;
945 sp.pppol2tp.addr.sin_family = AF_INET;
946 sp.pppol2tp.addr.sin_port = inet->inet_dport;
947 sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
948 memcpy(uaddr, &sp, len);
949 }
950
951 *usockaddr_len = len;
952 error = 0;
953
954 sock_put(pls->tunnel_sock);
955 end_put_sess:
956 sock_put(sk);
957 end:
958 return error;
959 }
960
961 /****************************************************************************
962 * ioctl() handlers.
963 *
964 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
965 * sockets. However, in order to control kernel tunnel features, we allow
966 * userspace to create a special "tunnel" PPPoX socket which is used for
967 * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
968 * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
969 * calls.
970 ****************************************************************************/
971
972 static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest,
973 struct l2tp_stats *stats)
974 {
975 dest->tx_packets = atomic_long_read(&stats->tx_packets);
976 dest->tx_bytes = atomic_long_read(&stats->tx_bytes);
977 dest->tx_errors = atomic_long_read(&stats->tx_errors);
978 dest->rx_packets = atomic_long_read(&stats->rx_packets);
979 dest->rx_bytes = atomic_long_read(&stats->rx_bytes);
980 dest->rx_seq_discards = atomic_long_read(&stats->rx_seq_discards);
981 dest->rx_oos_packets = atomic_long_read(&stats->rx_oos_packets);
982 dest->rx_errors = atomic_long_read(&stats->rx_errors);
983 }
984
985 /* Session ioctl helper.
986 */
987 static int pppol2tp_session_ioctl(struct l2tp_session *session,
988 unsigned int cmd, unsigned long arg)
989 {
990 struct ifreq ifr;
991 int err = 0;
992 struct sock *sk;
993 int val = (int) arg;
994 struct pppol2tp_session *ps = l2tp_session_priv(session);
995 struct l2tp_tunnel *tunnel = session->tunnel;
996 struct pppol2tp_ioc_stats stats;
997
998 l2tp_dbg(session, PPPOL2TP_MSG_CONTROL,
999 "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n",
1000 session->name, cmd, arg);
1001
1002 sk = ps->sock;
1003 if (!sk)
1004 return -EBADR;
1005
1006 sock_hold(sk);
1007
1008 switch (cmd) {
1009 case SIOCGIFMTU:
1010 err = -ENXIO;
1011 if (!(sk->sk_state & PPPOX_CONNECTED))
1012 break;
1013
1014 err = -EFAULT;
1015 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1016 break;
1017 ifr.ifr_mtu = session->mtu;
1018 if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq)))
1019 break;
1020
1021 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get mtu=%d\n",
1022 session->name, session->mtu);
1023 err = 0;
1024 break;
1025
1026 case SIOCSIFMTU:
1027 err = -ENXIO;
1028 if (!(sk->sk_state & PPPOX_CONNECTED))
1029 break;
1030
1031 err = -EFAULT;
1032 if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq)))
1033 break;
1034
1035 session->mtu = ifr.ifr_mtu;
1036
1037 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set mtu=%d\n",
1038 session->name, session->mtu);
1039 err = 0;
1040 break;
1041
1042 case PPPIOCGMRU:
1043 err = -ENXIO;
1044 if (!(sk->sk_state & PPPOX_CONNECTED))
1045 break;
1046
1047 err = -EFAULT;
1048 if (put_user(session->mru, (int __user *) arg))
1049 break;
1050
1051 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get mru=%d\n",
1052 session->name, session->mru);
1053 err = 0;
1054 break;
1055
1056 case PPPIOCSMRU:
1057 err = -ENXIO;
1058 if (!(sk->sk_state & PPPOX_CONNECTED))
1059 break;
1060
1061 err = -EFAULT;
1062 if (get_user(val, (int __user *) arg))
1063 break;
1064
1065 session->mru = val;
1066 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set mru=%d\n",
1067 session->name, session->mru);
1068 err = 0;
1069 break;
1070
1071 case PPPIOCGFLAGS:
1072 err = -EFAULT;
1073 if (put_user(ps->flags, (int __user *) arg))
1074 break;
1075
1076 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get flags=%d\n",
1077 session->name, ps->flags);
1078 err = 0;
1079 break;
1080
1081 case PPPIOCSFLAGS:
1082 err = -EFAULT;
1083 if (get_user(val, (int __user *) arg))
1084 break;
1085 ps->flags = val;
1086 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set flags=%d\n",
1087 session->name, ps->flags);
1088 err = 0;
1089 break;
1090
1091 case PPPIOCGL2TPSTATS:
1092 err = -ENXIO;
1093 if (!(sk->sk_state & PPPOX_CONNECTED))
1094 break;
1095
1096 memset(&stats, 0, sizeof(stats));
1097 stats.tunnel_id = tunnel->tunnel_id;
1098 stats.session_id = session->session_id;
1099 pppol2tp_copy_stats(&stats, &session->stats);
1100 if (copy_to_user((void __user *) arg, &stats,
1101 sizeof(stats)))
1102 break;
1103 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get L2TP stats\n",
1104 session->name);
1105 err = 0;
1106 break;
1107
1108 default:
1109 err = -ENOSYS;
1110 break;
1111 }
1112
1113 sock_put(sk);
1114
1115 return err;
1116 }
1117
1118 /* Tunnel ioctl helper.
1119 *
1120 * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data
1121 * specifies a session_id, the session ioctl handler is called. This allows an
1122 * application to retrieve session stats via a tunnel socket.
1123 */
1124 static int pppol2tp_tunnel_ioctl(struct l2tp_tunnel *tunnel,
1125 unsigned int cmd, unsigned long arg)
1126 {
1127 int err = 0;
1128 struct sock *sk;
1129 struct pppol2tp_ioc_stats stats;
1130
1131 l2tp_dbg(tunnel, PPPOL2TP_MSG_CONTROL,
1132 "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n",
1133 tunnel->name, cmd, arg);
1134
1135 sk = tunnel->sock;
1136 sock_hold(sk);
1137
1138 switch (cmd) {
1139 case PPPIOCGL2TPSTATS:
1140 err = -ENXIO;
1141 if (!(sk->sk_state & PPPOX_CONNECTED))
1142 break;
1143
1144 if (copy_from_user(&stats, (void __user *) arg,
1145 sizeof(stats))) {
1146 err = -EFAULT;
1147 break;
1148 }
1149 if (stats.session_id != 0) {
1150 /* resend to session ioctl handler */
1151 struct l2tp_session *session =
1152 l2tp_session_get(sock_net(sk), tunnel,
1153 stats.session_id, true);
1154
1155 if (session) {
1156 err = pppol2tp_session_ioctl(session, cmd,
1157 arg);
1158 if (session->deref)
1159 session->deref(session);
1160 l2tp_session_dec_refcount(session);
1161 } else {
1162 err = -EBADR;
1163 }
1164 break;
1165 }
1166 #ifdef CONFIG_XFRM
1167 stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0;
1168 #endif
1169 pppol2tp_copy_stats(&stats, &tunnel->stats);
1170 if (copy_to_user((void __user *) arg, &stats, sizeof(stats))) {
1171 err = -EFAULT;
1172 break;
1173 }
1174 l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: get L2TP stats\n",
1175 tunnel->name);
1176 err = 0;
1177 break;
1178
1179 default:
1180 err = -ENOSYS;
1181 break;
1182 }
1183
1184 sock_put(sk);
1185
1186 return err;
1187 }
1188
1189 /* Main ioctl() handler.
1190 * Dispatch to tunnel or session helpers depending on the socket.
1191 */
1192 static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
1193 unsigned long arg)
1194 {
1195 struct sock *sk = sock->sk;
1196 struct l2tp_session *session;
1197 struct l2tp_tunnel *tunnel;
1198 struct pppol2tp_session *ps;
1199 int err;
1200
1201 if (!sk)
1202 return 0;
1203
1204 err = -EBADF;
1205 if (sock_flag(sk, SOCK_DEAD) != 0)
1206 goto end;
1207
1208 err = -ENOTCONN;
1209 if ((sk->sk_user_data == NULL) ||
1210 (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND))))
1211 goto end;
1212
1213 /* Get session context from the socket */
1214 err = -EBADF;
1215 session = pppol2tp_sock_to_session(sk);
1216 if (session == NULL)
1217 goto end;
1218
1219 /* Special case: if session's session_id is zero, treat ioctl as a
1220 * tunnel ioctl
1221 */
1222 ps = l2tp_session_priv(session);
1223 if ((session->session_id == 0) &&
1224 (session->peer_session_id == 0)) {
1225 err = -EBADF;
1226 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1227 if (tunnel == NULL)
1228 goto end_put_sess;
1229
1230 err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
1231 sock_put(ps->tunnel_sock);
1232 goto end_put_sess;
1233 }
1234
1235 err = pppol2tp_session_ioctl(session, cmd, arg);
1236
1237 end_put_sess:
1238 sock_put(sk);
1239 end:
1240 return err;
1241 }
1242
1243 /*****************************************************************************
1244 * setsockopt() / getsockopt() support.
1245 *
1246 * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
1247 * sockets. In order to control kernel tunnel features, we allow userspace to
1248 * create a special "tunnel" PPPoX socket which is used for control only.
1249 * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
1250 * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
1251 *****************************************************************************/
1252
1253 /* Tunnel setsockopt() helper.
1254 */
1255 static int pppol2tp_tunnel_setsockopt(struct sock *sk,
1256 struct l2tp_tunnel *tunnel,
1257 int optname, int val)
1258 {
1259 int err = 0;
1260
1261 switch (optname) {
1262 case PPPOL2TP_SO_DEBUG:
1263 tunnel->debug = val;
1264 l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: set debug=%x\n",
1265 tunnel->name, tunnel->debug);
1266 break;
1267
1268 default:
1269 err = -ENOPROTOOPT;
1270 break;
1271 }
1272
1273 return err;
1274 }
1275
1276 /* Session setsockopt helper.
1277 */
1278 static int pppol2tp_session_setsockopt(struct sock *sk,
1279 struct l2tp_session *session,
1280 int optname, int val)
1281 {
1282 int err = 0;
1283 struct pppol2tp_session *ps = l2tp_session_priv(session);
1284
1285 switch (optname) {
1286 case PPPOL2TP_SO_RECVSEQ:
1287 if ((val != 0) && (val != 1)) {
1288 err = -EINVAL;
1289 break;
1290 }
1291 session->recv_seq = val ? -1 : 0;
1292 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1293 "%s: set recv_seq=%d\n",
1294 session->name, session->recv_seq);
1295 break;
1296
1297 case PPPOL2TP_SO_SENDSEQ:
1298 if ((val != 0) && (val != 1)) {
1299 err = -EINVAL;
1300 break;
1301 }
1302 session->send_seq = val ? -1 : 0;
1303 {
1304 struct sock *ssk = ps->sock;
1305 struct pppox_sock *po = pppox_sk(ssk);
1306 po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
1307 PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
1308 }
1309 l2tp_session_set_header_len(session, session->tunnel->version);
1310 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1311 "%s: set send_seq=%d\n",
1312 session->name, session->send_seq);
1313 break;
1314
1315 case PPPOL2TP_SO_LNSMODE:
1316 if ((val != 0) && (val != 1)) {
1317 err = -EINVAL;
1318 break;
1319 }
1320 session->lns_mode = val ? -1 : 0;
1321 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1322 "%s: set lns_mode=%d\n",
1323 session->name, session->lns_mode);
1324 break;
1325
1326 case PPPOL2TP_SO_DEBUG:
1327 session->debug = val;
1328 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set debug=%x\n",
1329 session->name, session->debug);
1330 break;
1331
1332 case PPPOL2TP_SO_REORDERTO:
1333 session->reorder_timeout = msecs_to_jiffies(val);
1334 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1335 "%s: set reorder_timeout=%d\n",
1336 session->name, session->reorder_timeout);
1337 break;
1338
1339 default:
1340 err = -ENOPROTOOPT;
1341 break;
1342 }
1343
1344 return err;
1345 }
1346
1347 /* Main setsockopt() entry point.
1348 * Does API checks, then calls either the tunnel or session setsockopt
1349 * handler, according to whether the PPPoL2TP socket is a for a regular
1350 * session or the special tunnel type.
1351 */
1352 static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
1353 char __user *optval, unsigned int optlen)
1354 {
1355 struct sock *sk = sock->sk;
1356 struct l2tp_session *session;
1357 struct l2tp_tunnel *tunnel;
1358 struct pppol2tp_session *ps;
1359 int val;
1360 int err;
1361
1362 if (level != SOL_PPPOL2TP)
1363 return -EINVAL;
1364
1365 if (optlen < sizeof(int))
1366 return -EINVAL;
1367
1368 if (get_user(val, (int __user *)optval))
1369 return -EFAULT;
1370
1371 err = -ENOTCONN;
1372 if (sk->sk_user_data == NULL)
1373 goto end;
1374
1375 /* Get session context from the socket */
1376 err = -EBADF;
1377 session = pppol2tp_sock_to_session(sk);
1378 if (session == NULL)
1379 goto end;
1380
1381 /* Special case: if session_id == 0x0000, treat as operation on tunnel
1382 */
1383 ps = l2tp_session_priv(session);
1384 if ((session->session_id == 0) &&
1385 (session->peer_session_id == 0)) {
1386 err = -EBADF;
1387 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1388 if (tunnel == NULL)
1389 goto end_put_sess;
1390
1391 err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
1392 sock_put(ps->tunnel_sock);
1393 } else
1394 err = pppol2tp_session_setsockopt(sk, session, optname, val);
1395
1396 err = 0;
1397
1398 end_put_sess:
1399 sock_put(sk);
1400 end:
1401 return err;
1402 }
1403
1404 /* Tunnel getsockopt helper. Called with sock locked.
1405 */
1406 static int pppol2tp_tunnel_getsockopt(struct sock *sk,
1407 struct l2tp_tunnel *tunnel,
1408 int optname, int *val)
1409 {
1410 int err = 0;
1411
1412 switch (optname) {
1413 case PPPOL2TP_SO_DEBUG:
1414 *val = tunnel->debug;
1415 l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: get debug=%x\n",
1416 tunnel->name, tunnel->debug);
1417 break;
1418
1419 default:
1420 err = -ENOPROTOOPT;
1421 break;
1422 }
1423
1424 return err;
1425 }
1426
1427 /* Session getsockopt helper. Called with sock locked.
1428 */
1429 static int pppol2tp_session_getsockopt(struct sock *sk,
1430 struct l2tp_session *session,
1431 int optname, int *val)
1432 {
1433 int err = 0;
1434
1435 switch (optname) {
1436 case PPPOL2TP_SO_RECVSEQ:
1437 *val = session->recv_seq;
1438 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1439 "%s: get recv_seq=%d\n", session->name, *val);
1440 break;
1441
1442 case PPPOL2TP_SO_SENDSEQ:
1443 *val = session->send_seq;
1444 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1445 "%s: get send_seq=%d\n", session->name, *val);
1446 break;
1447
1448 case PPPOL2TP_SO_LNSMODE:
1449 *val = session->lns_mode;
1450 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1451 "%s: get lns_mode=%d\n", session->name, *val);
1452 break;
1453
1454 case PPPOL2TP_SO_DEBUG:
1455 *val = session->debug;
1456 l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get debug=%d\n",
1457 session->name, *val);
1458 break;
1459
1460 case PPPOL2TP_SO_REORDERTO:
1461 *val = (int) jiffies_to_msecs(session->reorder_timeout);
1462 l2tp_info(session, PPPOL2TP_MSG_CONTROL,
1463 "%s: get reorder_timeout=%d\n", session->name, *val);
1464 break;
1465
1466 default:
1467 err = -ENOPROTOOPT;
1468 }
1469
1470 return err;
1471 }
1472
1473 /* Main getsockopt() entry point.
1474 * Does API checks, then calls either the tunnel or session getsockopt
1475 * handler, according to whether the PPPoX socket is a for a regular session
1476 * or the special tunnel type.
1477 */
1478 static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
1479 char __user *optval, int __user *optlen)
1480 {
1481 struct sock *sk = sock->sk;
1482 struct l2tp_session *session;
1483 struct l2tp_tunnel *tunnel;
1484 int val, len;
1485 int err;
1486 struct pppol2tp_session *ps;
1487
1488 if (level != SOL_PPPOL2TP)
1489 return -EINVAL;
1490
1491 if (get_user(len, optlen))
1492 return -EFAULT;
1493
1494 len = min_t(unsigned int, len, sizeof(int));
1495
1496 if (len < 0)
1497 return -EINVAL;
1498
1499 err = -ENOTCONN;
1500 if (sk->sk_user_data == NULL)
1501 goto end;
1502
1503 /* Get the session context */
1504 err = -EBADF;
1505 session = pppol2tp_sock_to_session(sk);
1506 if (session == NULL)
1507 goto end;
1508
1509 /* Special case: if session_id == 0x0000, treat as operation on tunnel */
1510 ps = l2tp_session_priv(session);
1511 if ((session->session_id == 0) &&
1512 (session->peer_session_id == 0)) {
1513 err = -EBADF;
1514 tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
1515 if (tunnel == NULL)
1516 goto end_put_sess;
1517
1518 err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
1519 sock_put(ps->tunnel_sock);
1520 } else
1521 err = pppol2tp_session_getsockopt(sk, session, optname, &val);
1522
1523 err = -EFAULT;
1524 if (put_user(len, optlen))
1525 goto end_put_sess;
1526
1527 if (copy_to_user((void __user *) optval, &val, len))
1528 goto end_put_sess;
1529
1530 err = 0;
1531
1532 end_put_sess:
1533 sock_put(sk);
1534 end:
1535 return err;
1536 }
1537
1538 /*****************************************************************************
1539 * /proc filesystem for debug
1540 * Since the original pppol2tp driver provided /proc/net/pppol2tp for
1541 * L2TPv2, we dump only L2TPv2 tunnels and sessions here.
1542 *****************************************************************************/
1543
1544 static unsigned int pppol2tp_net_id;
1545
1546 #ifdef CONFIG_PROC_FS
1547
1548 struct pppol2tp_seq_data {
1549 struct seq_net_private p;
1550 int tunnel_idx; /* current tunnel */
1551 int session_idx; /* index of session within current tunnel */
1552 struct l2tp_tunnel *tunnel;
1553 struct l2tp_session *session; /* NULL means get next tunnel */
1554 };
1555
1556 static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd)
1557 {
1558 for (;;) {
1559 pd->tunnel = l2tp_tunnel_find_nth(net, pd->tunnel_idx);
1560 pd->tunnel_idx++;
1561
1562 if (pd->tunnel == NULL)
1563 break;
1564
1565 /* Ignore L2TPv3 tunnels */
1566 if (pd->tunnel->version < 3)
1567 break;
1568 }
1569 }
1570
1571 static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd)
1572 {
1573 pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx, true);
1574 pd->session_idx++;
1575
1576 if (pd->session == NULL) {
1577 pd->session_idx = 0;
1578 pppol2tp_next_tunnel(net, pd);
1579 }
1580 }
1581
1582 static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
1583 {
1584 struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
1585 loff_t pos = *offs;
1586 struct net *net;
1587
1588 if (!pos)
1589 goto out;
1590
1591 BUG_ON(m->private == NULL);
1592 pd = m->private;
1593 net = seq_file_net(m);
1594
1595 if (pd->tunnel == NULL)
1596 pppol2tp_next_tunnel(net, pd);
1597 else
1598 pppol2tp_next_session(net, pd);
1599
1600 /* NULL tunnel and session indicates end of list */
1601 if ((pd->tunnel == NULL) && (pd->session == NULL))
1602 pd = NULL;
1603
1604 out:
1605 return pd;
1606 }
1607
1608 static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
1609 {
1610 (*pos)++;
1611 return NULL;
1612 }
1613
1614 static void pppol2tp_seq_stop(struct seq_file *p, void *v)
1615 {
1616 /* nothing to do */
1617 }
1618
1619 static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
1620 {
1621 struct l2tp_tunnel *tunnel = v;
1622
1623 seq_printf(m, "\nTUNNEL '%s', %c %d\n",
1624 tunnel->name,
1625 (tunnel == tunnel->sock->sk_user_data) ? 'Y' : 'N',
1626 atomic_read(&tunnel->ref_count) - 1);
1627 seq_printf(m, " %08x %ld/%ld/%ld %ld/%ld/%ld\n",
1628 tunnel->debug,
1629 atomic_long_read(&tunnel->stats.tx_packets),
1630 atomic_long_read(&tunnel->stats.tx_bytes),
1631 atomic_long_read(&tunnel->stats.tx_errors),
1632 atomic_long_read(&tunnel->stats.rx_packets),
1633 atomic_long_read(&tunnel->stats.rx_bytes),
1634 atomic_long_read(&tunnel->stats.rx_errors));
1635 }
1636
1637 static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
1638 {
1639 struct l2tp_session *session = v;
1640 struct l2tp_tunnel *tunnel = session->tunnel;
1641 struct pppol2tp_session *ps = l2tp_session_priv(session);
1642 struct pppox_sock *po = pppox_sk(ps->sock);
1643 u32 ip = 0;
1644 u16 port = 0;
1645
1646 if (tunnel->sock) {
1647 struct inet_sock *inet = inet_sk(tunnel->sock);
1648 ip = ntohl(inet->inet_saddr);
1649 port = ntohs(inet->inet_sport);
1650 }
1651
1652 seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
1653 "%04X/%04X %d %c\n",
1654 session->name, ip, port,
1655 tunnel->tunnel_id,
1656 session->session_id,
1657 tunnel->peer_tunnel_id,
1658 session->peer_session_id,
1659 ps->sock->sk_state,
1660 (session == ps->sock->sk_user_data) ?
1661 'Y' : 'N');
1662 seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n",
1663 session->mtu, session->mru,
1664 session->recv_seq ? 'R' : '-',
1665 session->send_seq ? 'S' : '-',
1666 session->lns_mode ? "LNS" : "LAC",
1667 session->debug,
1668 jiffies_to_msecs(session->reorder_timeout));
1669 seq_printf(m, " %hu/%hu %ld/%ld/%ld %ld/%ld/%ld\n",
1670 session->nr, session->ns,
1671 atomic_long_read(&session->stats.tx_packets),
1672 atomic_long_read(&session->stats.tx_bytes),
1673 atomic_long_read(&session->stats.tx_errors),
1674 atomic_long_read(&session->stats.rx_packets),
1675 atomic_long_read(&session->stats.rx_bytes),
1676 atomic_long_read(&session->stats.rx_errors));
1677
1678 if (po)
1679 seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
1680 }
1681
1682 static int pppol2tp_seq_show(struct seq_file *m, void *v)
1683 {
1684 struct pppol2tp_seq_data *pd = v;
1685
1686 /* display header on line 1 */
1687 if (v == SEQ_START_TOKEN) {
1688 seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
1689 seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
1690 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1691 seq_puts(m, " SESSION name, addr/port src-tid/sid "
1692 "dest-tid/sid state user-data-ok\n");
1693 seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
1694 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
1695 goto out;
1696 }
1697
1698 /* Show the tunnel or session context.
1699 */
1700 if (!pd->session) {
1701 pppol2tp_seq_tunnel_show(m, pd->tunnel);
1702 } else {
1703 pppol2tp_seq_session_show(m, pd->session);
1704 if (pd->session->deref)
1705 pd->session->deref(pd->session);
1706 l2tp_session_dec_refcount(pd->session);
1707 }
1708
1709 out:
1710 return 0;
1711 }
1712
1713 static const struct seq_operations pppol2tp_seq_ops = {
1714 .start = pppol2tp_seq_start,
1715 .next = pppol2tp_seq_next,
1716 .stop = pppol2tp_seq_stop,
1717 .show = pppol2tp_seq_show,
1718 };
1719
1720 /* Called when our /proc file is opened. We allocate data for use when
1721 * iterating our tunnel / session contexts and store it in the private
1722 * data of the seq_file.
1723 */
1724 static int pppol2tp_proc_open(struct inode *inode, struct file *file)
1725 {
1726 return seq_open_net(inode, file, &pppol2tp_seq_ops,
1727 sizeof(struct pppol2tp_seq_data));
1728 }
1729
1730 static const struct file_operations pppol2tp_proc_fops = {
1731 .owner = THIS_MODULE,
1732 .open = pppol2tp_proc_open,
1733 .read = seq_read,
1734 .llseek = seq_lseek,
1735 .release = seq_release_net,
1736 };
1737
1738 #endif /* CONFIG_PROC_FS */
1739
1740 /*****************************************************************************
1741 * Network namespace
1742 *****************************************************************************/
1743
1744 static __net_init int pppol2tp_init_net(struct net *net)
1745 {
1746 struct proc_dir_entry *pde;
1747 int err = 0;
1748
1749 pde = proc_create("pppol2tp", S_IRUGO, net->proc_net,
1750 &pppol2tp_proc_fops);
1751 if (!pde) {
1752 err = -ENOMEM;
1753 goto out;
1754 }
1755
1756 out:
1757 return err;
1758 }
1759
1760 static __net_exit void pppol2tp_exit_net(struct net *net)
1761 {
1762 remove_proc_entry("pppol2tp", net->proc_net);
1763 }
1764
1765 static struct pernet_operations pppol2tp_net_ops = {
1766 .init = pppol2tp_init_net,
1767 .exit = pppol2tp_exit_net,
1768 .id = &pppol2tp_net_id,
1769 };
1770
1771 /*****************************************************************************
1772 * Init and cleanup
1773 *****************************************************************************/
1774
1775 static const struct proto_ops pppol2tp_ops = {
1776 .family = AF_PPPOX,
1777 .owner = THIS_MODULE,
1778 .release = pppol2tp_release,
1779 .bind = sock_no_bind,
1780 .connect = pppol2tp_connect,
1781 .socketpair = sock_no_socketpair,
1782 .accept = sock_no_accept,
1783 .getname = pppol2tp_getname,
1784 .poll = datagram_poll,
1785 .listen = sock_no_listen,
1786 .shutdown = sock_no_shutdown,
1787 .setsockopt = pppol2tp_setsockopt,
1788 .getsockopt = pppol2tp_getsockopt,
1789 .sendmsg = pppol2tp_sendmsg,
1790 .recvmsg = pppol2tp_recvmsg,
1791 .mmap = sock_no_mmap,
1792 .ioctl = pppox_ioctl,
1793 #ifdef CONFIG_COMPAT
1794 .compat_ioctl = pppox_compat_ioctl,
1795 #endif
1796 };
1797
1798 static const struct pppox_proto pppol2tp_proto = {
1799 .create = pppol2tp_create,
1800 .ioctl = pppol2tp_ioctl,
1801 .owner = THIS_MODULE,
1802 };
1803
1804 #ifdef CONFIG_L2TP_V3
1805
1806 static const struct l2tp_nl_cmd_ops pppol2tp_nl_cmd_ops = {
1807 .session_create = pppol2tp_session_create,
1808 .session_delete = l2tp_session_delete,
1809 };
1810
1811 #endif /* CONFIG_L2TP_V3 */
1812
1813 static int __init pppol2tp_init(void)
1814 {
1815 int err;
1816
1817 err = register_pernet_device(&pppol2tp_net_ops);
1818 if (err)
1819 goto out;
1820
1821 err = proto_register(&pppol2tp_sk_proto, 0);
1822 if (err)
1823 goto out_unregister_pppol2tp_pernet;
1824
1825 err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
1826 if (err)
1827 goto out_unregister_pppol2tp_proto;
1828
1829 #ifdef CONFIG_L2TP_V3
1830 err = l2tp_nl_register_ops(L2TP_PWTYPE_PPP, &pppol2tp_nl_cmd_ops);
1831 if (err)
1832 goto out_unregister_pppox;
1833 #endif
1834
1835 pr_info("PPPoL2TP kernel driver, %s\n", PPPOL2TP_DRV_VERSION);
1836
1837 out:
1838 return err;
1839
1840 #ifdef CONFIG_L2TP_V3
1841 out_unregister_pppox:
1842 unregister_pppox_proto(PX_PROTO_OL2TP);
1843 #endif
1844 out_unregister_pppol2tp_proto:
1845 proto_unregister(&pppol2tp_sk_proto);
1846 out_unregister_pppol2tp_pernet:
1847 unregister_pernet_device(&pppol2tp_net_ops);
1848 goto out;
1849 }
1850
1851 static void __exit pppol2tp_exit(void)
1852 {
1853 #ifdef CONFIG_L2TP_V3
1854 l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
1855 #endif
1856 unregister_pppox_proto(PX_PROTO_OL2TP);
1857 proto_unregister(&pppol2tp_sk_proto);
1858 unregister_pernet_device(&pppol2tp_net_ops);
1859 }
1860
1861 module_init(pppol2tp_init);
1862 module_exit(pppol2tp_exit);
1863
1864 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1865 MODULE_DESCRIPTION("PPP over L2TP over UDP");
1866 MODULE_LICENSE("GPL");
1867 MODULE_VERSION(PPPOL2TP_DRV_VERSION);
1868 MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OL2TP);
1869 MODULE_ALIAS_L2TP_PWTYPE(7);
Linux with added FPC-III support