1 /*
2 * L2TP netlink layer, for management
3 *
4 * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
5 *
6 * Partly based on the IrDA nelink implementation
7 * (see net/irda/irnetlink.c) which is:
8 * Copyright (c) 2007 Samuel Ortiz <samuel@sortiz.org>
9 * which is in turn partly based on the wireless netlink code:
10 * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 */
16
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19 #include <net/sock.h>
20 #include <net/genetlink.h>
21 #include <net/udp.h>
22 #include <linux/in.h>
23 #include <linux/udp.h>
24 #include <linux/socket.h>
25 #include <linux/module.h>
26 #include <linux/list.h>
27 #include <net/net_namespace.h>
28
29 #include <linux/l2tp.h>
30
31 #include "l2tp_core.h"
32
33
34 static struct genl_family l2tp_nl_family = {
35 .id = GENL_ID_GENERATE,
36 .name = L2TP_GENL_NAME,
37 .version = L2TP_GENL_VERSION,
38 .hdrsize = 0,
39 .maxattr = L2TP_ATTR_MAX,
40 .netnsok = true,
41 };
42
43 static const struct genl_multicast_group l2tp_multicast_group[] = {
44 {
45 .name = L2TP_GENL_MCGROUP,
46 },
47 };
48
49 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq,
50 int flags, struct l2tp_tunnel *tunnel, u8 cmd);
51 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq,
52 int flags, struct l2tp_session *session,
53 u8 cmd);
54
55 /* Accessed under genl lock */
56 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
57
l2tp_nl_session_get(struct genl_info * info,bool do_ref)58 static struct l2tp_session *l2tp_nl_session_get(struct genl_info *info,
59 bool do_ref)
60 {
61 u32 tunnel_id;
62 u32 session_id;
63 char *ifname;
64 struct l2tp_tunnel *tunnel;
65 struct l2tp_session *session = NULL;
66 struct net *net = genl_info_net(info);
67
68 if (info->attrs[L2TP_ATTR_IFNAME]) {
69 ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
70 session = l2tp_session_get_by_ifname(net, ifname, do_ref);
71 } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
72 (info->attrs[L2TP_ATTR_CONN_ID])) {
73 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
74 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
75 tunnel = l2tp_tunnel_find(net, tunnel_id);
76 if (tunnel)
77 session = l2tp_session_get(net, tunnel, session_id,
78 do_ref);
79 }
80
81 return session;
82 }
83
l2tp_nl_cmd_noop(struct sk_buff * skb,struct genl_info * info)84 static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
85 {
86 struct sk_buff *msg;
87 void *hdr;
88 int ret = -ENOBUFS;
89
90 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
91 if (!msg) {
92 ret = -ENOMEM;
93 goto out;
94 }
95
96 hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
97 &l2tp_nl_family, 0, L2TP_CMD_NOOP);
98 if (!hdr) {
99 ret = -EMSGSIZE;
100 goto err_out;
101 }
102
103 genlmsg_end(msg, hdr);
104
105 return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
106
107 err_out:
108 nlmsg_free(msg);
109
110 out:
111 return ret;
112 }
113
l2tp_tunnel_notify(struct genl_family * family,struct genl_info * info,struct l2tp_tunnel * tunnel,u8 cmd)114 static int l2tp_tunnel_notify(struct genl_family *family,
115 struct genl_info *info,
116 struct l2tp_tunnel *tunnel,
117 u8 cmd)
118 {
119 struct sk_buff *msg;
120 int ret;
121
122 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
123 if (!msg)
124 return -ENOMEM;
125
126 ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
127 NLM_F_ACK, tunnel, cmd);
128
129 if (ret >= 0) {
130 ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
131 /* We don't care if no one is listening */
132 if (ret == -ESRCH)
133 ret = 0;
134 return ret;
135 }
136
137 nlmsg_free(msg);
138
139 return ret;
140 }
141
l2tp_session_notify(struct genl_family * family,struct genl_info * info,struct l2tp_session * session,u8 cmd)142 static int l2tp_session_notify(struct genl_family *family,
143 struct genl_info *info,
144 struct l2tp_session *session,
145 u8 cmd)
146 {
147 struct sk_buff *msg;
148 int ret;
149
150 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
151 if (!msg)
152 return -ENOMEM;
153
154 ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
155 NLM_F_ACK, session, cmd);
156
157 if (ret >= 0) {
158 ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
159 /* We don't care if no one is listening */
160 if (ret == -ESRCH)
161 ret = 0;
162 return ret;
163 }
164
165 nlmsg_free(msg);
166
167 return ret;
168 }
169
l2tp_nl_cmd_tunnel_create(struct sk_buff * skb,struct genl_info * info)170 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
171 {
172 u32 tunnel_id;
173 u32 peer_tunnel_id;
174 int proto_version;
175 int fd;
176 int ret = 0;
177 struct l2tp_tunnel_cfg cfg = { 0, };
178 struct l2tp_tunnel *tunnel;
179 struct net *net = genl_info_net(info);
180
181 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
182 ret = -EINVAL;
183 goto out;
184 }
185 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
186
187 if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
188 ret = -EINVAL;
189 goto out;
190 }
191 peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
192
193 if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
194 ret = -EINVAL;
195 goto out;
196 }
197 proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
198
199 if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
200 ret = -EINVAL;
201 goto out;
202 }
203 cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
204
205 fd = -1;
206 if (info->attrs[L2TP_ATTR_FD]) {
207 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
208 } else {
209 #if IS_ENABLED(CONFIG_IPV6)
210 if (info->attrs[L2TP_ATTR_IP6_SADDR] &&
211 info->attrs[L2TP_ATTR_IP6_DADDR]) {
212 cfg.local_ip6 = nla_data(
213 info->attrs[L2TP_ATTR_IP6_SADDR]);
214 cfg.peer_ip6 = nla_data(
215 info->attrs[L2TP_ATTR_IP6_DADDR]);
216 } else
217 #endif
218 if (info->attrs[L2TP_ATTR_IP_SADDR] &&
219 info->attrs[L2TP_ATTR_IP_DADDR]) {
220 cfg.local_ip.s_addr = nla_get_in_addr(
221 info->attrs[L2TP_ATTR_IP_SADDR]);
222 cfg.peer_ip.s_addr = nla_get_in_addr(
223 info->attrs[L2TP_ATTR_IP_DADDR]);
224 } else {
225 ret = -EINVAL;
226 goto out;
227 }
228 if (info->attrs[L2TP_ATTR_UDP_SPORT])
229 cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
230 if (info->attrs[L2TP_ATTR_UDP_DPORT])
231 cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
232 if (info->attrs[L2TP_ATTR_UDP_CSUM])
233 cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
234
235 #if IS_ENABLED(CONFIG_IPV6)
236 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX])
237 cfg.udp6_zero_tx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
238 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX])
239 cfg.udp6_zero_rx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
240 #endif
241 }
242
243 if (info->attrs[L2TP_ATTR_DEBUG])
244 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
245
246 tunnel = l2tp_tunnel_find(net, tunnel_id);
247 if (tunnel != NULL) {
248 ret = -EEXIST;
249 goto out;
250 }
251
252 ret = -EINVAL;
253 switch (cfg.encap) {
254 case L2TP_ENCAPTYPE_UDP:
255 case L2TP_ENCAPTYPE_IP:
256 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
257 peer_tunnel_id, &cfg, &tunnel);
258 break;
259 }
260
261 if (ret >= 0)
262 ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
263 tunnel, L2TP_CMD_TUNNEL_CREATE);
264 out:
265 return ret;
266 }
267
l2tp_nl_cmd_tunnel_delete(struct sk_buff * skb,struct genl_info * info)268 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
269 {
270 struct l2tp_tunnel *tunnel;
271 u32 tunnel_id;
272 int ret = 0;
273 struct net *net = genl_info_net(info);
274
275 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
276 ret = -EINVAL;
277 goto out;
278 }
279 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
280
281 tunnel = l2tp_tunnel_find(net, tunnel_id);
282 if (tunnel == NULL) {
283 ret = -ENODEV;
284 goto out;
285 }
286
287 l2tp_tunnel_notify(&l2tp_nl_family, info,
288 tunnel, L2TP_CMD_TUNNEL_DELETE);
289
290 l2tp_tunnel_delete(tunnel);
291
292 out:
293 return ret;
294 }
295
l2tp_nl_cmd_tunnel_modify(struct sk_buff * skb,struct genl_info * info)296 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
297 {
298 struct l2tp_tunnel *tunnel;
299 u32 tunnel_id;
300 int ret = 0;
301 struct net *net = genl_info_net(info);
302
303 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
304 ret = -EINVAL;
305 goto out;
306 }
307 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
308
309 tunnel = l2tp_tunnel_find(net, tunnel_id);
310 if (tunnel == NULL) {
311 ret = -ENODEV;
312 goto out;
313 }
314
315 if (info->attrs[L2TP_ATTR_DEBUG])
316 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
317
318 ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
319 tunnel, L2TP_CMD_TUNNEL_MODIFY);
320
321 out:
322 return ret;
323 }
324
l2tp_nl_tunnel_send(struct sk_buff * skb,u32 portid,u32 seq,int flags,struct l2tp_tunnel * tunnel,u8 cmd)325 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
326 struct l2tp_tunnel *tunnel, u8 cmd)
327 {
328 void *hdr;
329 struct nlattr *nest;
330 struct sock *sk = NULL;
331 struct inet_sock *inet;
332 #if IS_ENABLED(CONFIG_IPV6)
333 struct ipv6_pinfo *np = NULL;
334 #endif
335
336 hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
337 if (!hdr)
338 return -EMSGSIZE;
339
340 if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
341 nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
342 nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
343 nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
344 nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
345 goto nla_put_failure;
346
347 nest = nla_nest_start(skb, L2TP_ATTR_STATS);
348 if (nest == NULL)
349 goto nla_put_failure;
350
351 if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
352 atomic_long_read(&tunnel->stats.tx_packets),
353 L2TP_ATTR_STATS_PAD) ||
354 nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
355 atomic_long_read(&tunnel->stats.tx_bytes),
356 L2TP_ATTR_STATS_PAD) ||
357 nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
358 atomic_long_read(&tunnel->stats.tx_errors),
359 L2TP_ATTR_STATS_PAD) ||
360 nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
361 atomic_long_read(&tunnel->stats.rx_packets),
362 L2TP_ATTR_STATS_PAD) ||
363 nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
364 atomic_long_read(&tunnel->stats.rx_bytes),
365 L2TP_ATTR_STATS_PAD) ||
366 nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
367 atomic_long_read(&tunnel->stats.rx_seq_discards),
368 L2TP_ATTR_STATS_PAD) ||
369 nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
370 atomic_long_read(&tunnel->stats.rx_oos_packets),
371 L2TP_ATTR_STATS_PAD) ||
372 nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
373 atomic_long_read(&tunnel->stats.rx_errors),
374 L2TP_ATTR_STATS_PAD))
375 goto nla_put_failure;
376 nla_nest_end(skb, nest);
377
378 sk = tunnel->sock;
379 if (!sk)
380 goto out;
381
382 #if IS_ENABLED(CONFIG_IPV6)
383 if (sk->sk_family == AF_INET6)
384 np = inet6_sk(sk);
385 #endif
386
387 inet = inet_sk(sk);
388
389 switch (tunnel->encap) {
390 case L2TP_ENCAPTYPE_UDP:
391 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
392 nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
393 nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx))
394 goto nla_put_failure;
395 /* NOBREAK */
396 case L2TP_ENCAPTYPE_IP:
397 #if IS_ENABLED(CONFIG_IPV6)
398 if (np) {
399 if (nla_put_in6_addr(skb, L2TP_ATTR_IP6_SADDR,
400 &np->saddr) ||
401 nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR,
402 &sk->sk_v6_daddr))
403 goto nla_put_failure;
404 } else
405 #endif
406 if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR,
407 inet->inet_saddr) ||
408 nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR,
409 inet->inet_daddr))
410 goto nla_put_failure;
411 break;
412 }
413
414 out:
415 genlmsg_end(skb, hdr);
416 return 0;
417
418 nla_put_failure:
419 genlmsg_cancel(skb, hdr);
420 return -1;
421 }
422
l2tp_nl_cmd_tunnel_get(struct sk_buff * skb,struct genl_info * info)423 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
424 {
425 struct l2tp_tunnel *tunnel;
426 struct sk_buff *msg;
427 u32 tunnel_id;
428 int ret = -ENOBUFS;
429 struct net *net = genl_info_net(info);
430
431 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
432 ret = -EINVAL;
433 goto out;
434 }
435
436 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
437
438 tunnel = l2tp_tunnel_find(net, tunnel_id);
439 if (tunnel == NULL) {
440 ret = -ENODEV;
441 goto out;
442 }
443
444 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
445 if (!msg) {
446 ret = -ENOMEM;
447 goto out;
448 }
449
450 ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
451 NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
452 if (ret < 0)
453 goto err_out;
454
455 return genlmsg_unicast(net, msg, info->snd_portid);
456
457 err_out:
458 nlmsg_free(msg);
459
460 out:
461 return ret;
462 }
463
l2tp_nl_cmd_tunnel_dump(struct sk_buff * skb,struct netlink_callback * cb)464 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
465 {
466 int ti = cb->args[0];
467 struct l2tp_tunnel *tunnel;
468 struct net *net = sock_net(skb->sk);
469
470 for (;;) {
471 tunnel = l2tp_tunnel_find_nth(net, ti);
472 if (tunnel == NULL)
473 goto out;
474
475 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
476 cb->nlh->nlmsg_seq, NLM_F_MULTI,
477 tunnel, L2TP_CMD_TUNNEL_GET) < 0)
478 goto out;
479
480 ti++;
481 }
482
483 out:
484 cb->args[0] = ti;
485
486 return skb->len;
487 }
488
l2tp_nl_cmd_session_create(struct sk_buff * skb,struct genl_info * info)489 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
490 {
491 u32 tunnel_id = 0;
492 u32 session_id;
493 u32 peer_session_id;
494 int ret = 0;
495 struct l2tp_tunnel *tunnel;
496 struct l2tp_session *session;
497 struct l2tp_session_cfg cfg = { 0, };
498 struct net *net = genl_info_net(info);
499
500 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
501 ret = -EINVAL;
502 goto out;
503 }
504 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
505 tunnel = l2tp_tunnel_find(net, tunnel_id);
506 if (!tunnel) {
507 ret = -ENODEV;
508 goto out;
509 }
510
511 if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
512 ret = -EINVAL;
513 goto out;
514 }
515 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
516 session = l2tp_session_find(net, tunnel, session_id);
517 if (session) {
518 ret = -EEXIST;
519 goto out;
520 }
521
522 if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
523 ret = -EINVAL;
524 goto out;
525 }
526 peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
527
528 if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
529 ret = -EINVAL;
530 goto out;
531 }
532 cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
533 if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
534 ret = -EINVAL;
535 goto out;
536 }
537
538 if (tunnel->version > 2) {
539 if (info->attrs[L2TP_ATTR_OFFSET])
540 cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
541
542 if (info->attrs[L2TP_ATTR_DATA_SEQ])
543 cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
544
545 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
546 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
547 cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
548
549 cfg.l2specific_len = 4;
550 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
551 cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
552
553 if (info->attrs[L2TP_ATTR_COOKIE]) {
554 u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
555 if (len > 8) {
556 ret = -EINVAL;
557 goto out;
558 }
559 cfg.cookie_len = len;
560 memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
561 }
562 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
563 u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
564 if (len > 8) {
565 ret = -EINVAL;
566 goto out;
567 }
568 cfg.peer_cookie_len = len;
569 memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
570 }
571 if (info->attrs[L2TP_ATTR_IFNAME])
572 cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
573
574 if (info->attrs[L2TP_ATTR_VLAN_ID])
575 cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
576 }
577
578 if (info->attrs[L2TP_ATTR_DEBUG])
579 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
580
581 if (info->attrs[L2TP_ATTR_RECV_SEQ])
582 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
583
584 if (info->attrs[L2TP_ATTR_SEND_SEQ])
585 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
586
587 if (info->attrs[L2TP_ATTR_LNS_MODE])
588 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
589
590 if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
591 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
592
593 if (info->attrs[L2TP_ATTR_MTU])
594 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
595
596 if (info->attrs[L2TP_ATTR_MRU])
597 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
598
599 #ifdef CONFIG_MODULES
600 if (l2tp_nl_cmd_ops[cfg.pw_type] == NULL) {
601 genl_unlock();
602 request_module("net-l2tp-type-%u", cfg.pw_type);
603 genl_lock();
604 }
605 #endif
606 if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
607 (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
608 ret = -EPROTONOSUPPORT;
609 goto out;
610 }
611
612 /* Check that pseudowire-specific params are present */
613 switch (cfg.pw_type) {
614 case L2TP_PWTYPE_NONE:
615 break;
616 case L2TP_PWTYPE_ETH_VLAN:
617 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
618 ret = -EINVAL;
619 goto out;
620 }
621 break;
622 case L2TP_PWTYPE_ETH:
623 break;
624 case L2TP_PWTYPE_PPP:
625 case L2TP_PWTYPE_PPP_AC:
626 break;
627 case L2TP_PWTYPE_IP:
628 default:
629 ret = -EPROTONOSUPPORT;
630 break;
631 }
632
633 ret = -EPROTONOSUPPORT;
634 if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
635 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
636 session_id, peer_session_id, &cfg);
637
638 if (ret >= 0) {
639 session = l2tp_session_get(net, tunnel, session_id, false);
640 if (session) {
641 ret = l2tp_session_notify(&l2tp_nl_family, info, session,
642 L2TP_CMD_SESSION_CREATE);
643 l2tp_session_dec_refcount(session);
644 }
645 }
646
647 out:
648 return ret;
649 }
650
l2tp_nl_cmd_session_delete(struct sk_buff * skb,struct genl_info * info)651 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
652 {
653 int ret = 0;
654 struct l2tp_session *session;
655 u16 pw_type;
656
657 session = l2tp_nl_session_get(info, true);
658 if (session == NULL) {
659 ret = -ENODEV;
660 goto out;
661 }
662
663 l2tp_session_notify(&l2tp_nl_family, info,
664 session, L2TP_CMD_SESSION_DELETE);
665
666 pw_type = session->pwtype;
667 if (pw_type < __L2TP_PWTYPE_MAX)
668 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
669 ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
670
671 if (session->deref)
672 session->deref(session);
673 l2tp_session_dec_refcount(session);
674
675 out:
676 return ret;
677 }
678
l2tp_nl_cmd_session_modify(struct sk_buff * skb,struct genl_info * info)679 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
680 {
681 int ret = 0;
682 struct l2tp_session *session;
683
684 session = l2tp_nl_session_get(info, false);
685 if (session == NULL) {
686 ret = -ENODEV;
687 goto out;
688 }
689
690 if (info->attrs[L2TP_ATTR_DEBUG])
691 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
692
693 if (info->attrs[L2TP_ATTR_DATA_SEQ])
694 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
695
696 if (info->attrs[L2TP_ATTR_RECV_SEQ])
697 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
698
699 if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
700 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
701 l2tp_session_set_header_len(session, session->tunnel->version);
702 }
703
704 if (info->attrs[L2TP_ATTR_LNS_MODE])
705 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
706
707 if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
708 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
709
710 if (info->attrs[L2TP_ATTR_MTU])
711 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
712
713 if (info->attrs[L2TP_ATTR_MRU])
714 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
715
716 ret = l2tp_session_notify(&l2tp_nl_family, info,
717 session, L2TP_CMD_SESSION_MODIFY);
718
719 l2tp_session_dec_refcount(session);
720
721 out:
722 return ret;
723 }
724
l2tp_nl_session_send(struct sk_buff * skb,u32 portid,u32 seq,int flags,struct l2tp_session * session,u8 cmd)725 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
726 struct l2tp_session *session, u8 cmd)
727 {
728 void *hdr;
729 struct nlattr *nest;
730 struct l2tp_tunnel *tunnel = session->tunnel;
731 struct sock *sk = NULL;
732
733 sk = tunnel->sock;
734
735 hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
736 if (!hdr)
737 return -EMSGSIZE;
738
739 if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
740 nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
741 nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
742 nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
743 session->peer_session_id) ||
744 nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
745 nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
746 nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
747 (session->mru &&
748 nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
749 goto nla_put_failure;
750
751 if ((session->ifname[0] &&
752 nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
753 (session->offset &&
754 nla_put_u16(skb, L2TP_ATTR_OFFSET, session->offset)) ||
755 (session->cookie_len &&
756 nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
757 &session->cookie[0])) ||
758 (session->peer_cookie_len &&
759 nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
760 &session->peer_cookie[0])) ||
761 nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
762 nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
763 nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
764 #ifdef CONFIG_XFRM
765 (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
766 nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
767 #endif
768 (session->reorder_timeout &&
769 nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT,
770 session->reorder_timeout, L2TP_ATTR_PAD)))
771 goto nla_put_failure;
772
773 nest = nla_nest_start(skb, L2TP_ATTR_STATS);
774 if (nest == NULL)
775 goto nla_put_failure;
776
777 if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
778 atomic_long_read(&session->stats.tx_packets),
779 L2TP_ATTR_STATS_PAD) ||
780 nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
781 atomic_long_read(&session->stats.tx_bytes),
782 L2TP_ATTR_STATS_PAD) ||
783 nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
784 atomic_long_read(&session->stats.tx_errors),
785 L2TP_ATTR_STATS_PAD) ||
786 nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
787 atomic_long_read(&session->stats.rx_packets),
788 L2TP_ATTR_STATS_PAD) ||
789 nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
790 atomic_long_read(&session->stats.rx_bytes),
791 L2TP_ATTR_STATS_PAD) ||
792 nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
793 atomic_long_read(&session->stats.rx_seq_discards),
794 L2TP_ATTR_STATS_PAD) ||
795 nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
796 atomic_long_read(&session->stats.rx_oos_packets),
797 L2TP_ATTR_STATS_PAD) ||
798 nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
799 atomic_long_read(&session->stats.rx_errors),
800 L2TP_ATTR_STATS_PAD))
801 goto nla_put_failure;
802 nla_nest_end(skb, nest);
803
804 genlmsg_end(skb, hdr);
805 return 0;
806
807 nla_put_failure:
808 genlmsg_cancel(skb, hdr);
809 return -1;
810 }
811
l2tp_nl_cmd_session_get(struct sk_buff * skb,struct genl_info * info)812 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
813 {
814 struct l2tp_session *session;
815 struct sk_buff *msg;
816 int ret;
817
818 session = l2tp_nl_session_get(info, false);
819 if (session == NULL) {
820 ret = -ENODEV;
821 goto err;
822 }
823
824 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
825 if (!msg) {
826 ret = -ENOMEM;
827 goto err_ref;
828 }
829
830 ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
831 0, session, L2TP_CMD_SESSION_GET);
832 if (ret < 0)
833 goto err_ref_msg;
834
835 ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
836
837 l2tp_session_dec_refcount(session);
838
839 return ret;
840
841 err_ref_msg:
842 nlmsg_free(msg);
843 err_ref:
844 l2tp_session_dec_refcount(session);
845 err:
846 return ret;
847 }
848
l2tp_nl_cmd_session_dump(struct sk_buff * skb,struct netlink_callback * cb)849 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
850 {
851 struct net *net = sock_net(skb->sk);
852 struct l2tp_session *session;
853 struct l2tp_tunnel *tunnel = NULL;
854 int ti = cb->args[0];
855 int si = cb->args[1];
856
857 for (;;) {
858 if (tunnel == NULL) {
859 tunnel = l2tp_tunnel_find_nth(net, ti);
860 if (tunnel == NULL)
861 goto out;
862 }
863
864 session = l2tp_session_get_nth(tunnel, si, false);
865 if (session == NULL) {
866 ti++;
867 tunnel = NULL;
868 si = 0;
869 continue;
870 }
871
872 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
873 cb->nlh->nlmsg_seq, NLM_F_MULTI,
874 session, L2TP_CMD_SESSION_GET) < 0) {
875 l2tp_session_dec_refcount(session);
876 break;
877 }
878 l2tp_session_dec_refcount(session);
879
880 si++;
881 }
882
883 out:
884 cb->args[0] = ti;
885 cb->args[1] = si;
886
887 return skb->len;
888 }
889
890 static const struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
891 [L2TP_ATTR_NONE] = { .type = NLA_UNSPEC, },
892 [L2TP_ATTR_PW_TYPE] = { .type = NLA_U16, },
893 [L2TP_ATTR_ENCAP_TYPE] = { .type = NLA_U16, },
894 [L2TP_ATTR_OFFSET] = { .type = NLA_U16, },
895 [L2TP_ATTR_DATA_SEQ] = { .type = NLA_U8, },
896 [L2TP_ATTR_L2SPEC_TYPE] = { .type = NLA_U8, },
897 [L2TP_ATTR_L2SPEC_LEN] = { .type = NLA_U8, },
898 [L2TP_ATTR_PROTO_VERSION] = { .type = NLA_U8, },
899 [L2TP_ATTR_CONN_ID] = { .type = NLA_U32, },
900 [L2TP_ATTR_PEER_CONN_ID] = { .type = NLA_U32, },
901 [L2TP_ATTR_SESSION_ID] = { .type = NLA_U32, },
902 [L2TP_ATTR_PEER_SESSION_ID] = { .type = NLA_U32, },
903 [L2TP_ATTR_UDP_CSUM] = { .type = NLA_U8, },
904 [L2TP_ATTR_VLAN_ID] = { .type = NLA_U16, },
905 [L2TP_ATTR_DEBUG] = { .type = NLA_U32, },
906 [L2TP_ATTR_RECV_SEQ] = { .type = NLA_U8, },
907 [L2TP_ATTR_SEND_SEQ] = { .type = NLA_U8, },
908 [L2TP_ATTR_LNS_MODE] = { .type = NLA_U8, },
909 [L2TP_ATTR_USING_IPSEC] = { .type = NLA_U8, },
910 [L2TP_ATTR_RECV_TIMEOUT] = { .type = NLA_MSECS, },
911 [L2TP_ATTR_FD] = { .type = NLA_U32, },
912 [L2TP_ATTR_IP_SADDR] = { .type = NLA_U32, },
913 [L2TP_ATTR_IP_DADDR] = { .type = NLA_U32, },
914 [L2TP_ATTR_UDP_SPORT] = { .type = NLA_U16, },
915 [L2TP_ATTR_UDP_DPORT] = { .type = NLA_U16, },
916 [L2TP_ATTR_MTU] = { .type = NLA_U16, },
917 [L2TP_ATTR_MRU] = { .type = NLA_U16, },
918 [L2TP_ATTR_STATS] = { .type = NLA_NESTED, },
919 [L2TP_ATTR_IP6_SADDR] = {
920 .type = NLA_BINARY,
921 .len = sizeof(struct in6_addr),
922 },
923 [L2TP_ATTR_IP6_DADDR] = {
924 .type = NLA_BINARY,
925 .len = sizeof(struct in6_addr),
926 },
927 [L2TP_ATTR_IFNAME] = {
928 .type = NLA_NUL_STRING,
929 .len = IFNAMSIZ - 1,
930 },
931 [L2TP_ATTR_COOKIE] = {
932 .type = NLA_BINARY,
933 .len = 8,
934 },
935 [L2TP_ATTR_PEER_COOKIE] = {
936 .type = NLA_BINARY,
937 .len = 8,
938 },
939 };
940
941 static const struct genl_ops l2tp_nl_ops[] = {
942 {
943 .cmd = L2TP_CMD_NOOP,
944 .doit = l2tp_nl_cmd_noop,
945 .policy = l2tp_nl_policy,
946 /* can be retrieved by unprivileged users */
947 },
948 {
949 .cmd = L2TP_CMD_TUNNEL_CREATE,
950 .doit = l2tp_nl_cmd_tunnel_create,
951 .policy = l2tp_nl_policy,
952 .flags = GENL_ADMIN_PERM,
953 },
954 {
955 .cmd = L2TP_CMD_TUNNEL_DELETE,
956 .doit = l2tp_nl_cmd_tunnel_delete,
957 .policy = l2tp_nl_policy,
958 .flags = GENL_ADMIN_PERM,
959 },
960 {
961 .cmd = L2TP_CMD_TUNNEL_MODIFY,
962 .doit = l2tp_nl_cmd_tunnel_modify,
963 .policy = l2tp_nl_policy,
964 .flags = GENL_ADMIN_PERM,
965 },
966 {
967 .cmd = L2TP_CMD_TUNNEL_GET,
968 .doit = l2tp_nl_cmd_tunnel_get,
969 .dumpit = l2tp_nl_cmd_tunnel_dump,
970 .policy = l2tp_nl_policy,
971 .flags = GENL_ADMIN_PERM,
972 },
973 {
974 .cmd = L2TP_CMD_SESSION_CREATE,
975 .doit = l2tp_nl_cmd_session_create,
976 .policy = l2tp_nl_policy,
977 .flags = GENL_ADMIN_PERM,
978 },
979 {
980 .cmd = L2TP_CMD_SESSION_DELETE,
981 .doit = l2tp_nl_cmd_session_delete,
982 .policy = l2tp_nl_policy,
983 .flags = GENL_ADMIN_PERM,
984 },
985 {
986 .cmd = L2TP_CMD_SESSION_MODIFY,
987 .doit = l2tp_nl_cmd_session_modify,
988 .policy = l2tp_nl_policy,
989 .flags = GENL_ADMIN_PERM,
990 },
991 {
992 .cmd = L2TP_CMD_SESSION_GET,
993 .doit = l2tp_nl_cmd_session_get,
994 .dumpit = l2tp_nl_cmd_session_dump,
995 .policy = l2tp_nl_policy,
996 .flags = GENL_ADMIN_PERM,
997 },
998 };
999
l2tp_nl_register_ops(enum l2tp_pwtype pw_type,const struct l2tp_nl_cmd_ops * ops)1000 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
1001 {
1002 int ret;
1003
1004 ret = -EINVAL;
1005 if (pw_type >= __L2TP_PWTYPE_MAX)
1006 goto err;
1007
1008 genl_lock();
1009 ret = -EBUSY;
1010 if (l2tp_nl_cmd_ops[pw_type])
1011 goto out;
1012
1013 l2tp_nl_cmd_ops[pw_type] = ops;
1014 ret = 0;
1015
1016 out:
1017 genl_unlock();
1018 err:
1019 return ret;
1020 }
1021 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
1022
l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)1023 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
1024 {
1025 if (pw_type < __L2TP_PWTYPE_MAX) {
1026 genl_lock();
1027 l2tp_nl_cmd_ops[pw_type] = NULL;
1028 genl_unlock();
1029 }
1030 }
1031 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
1032
l2tp_nl_init(void)1033 static int l2tp_nl_init(void)
1034 {
1035 pr_info("L2TP netlink interface\n");
1036 return genl_register_family_with_ops_groups(&l2tp_nl_family,
1037 l2tp_nl_ops,
1038 l2tp_multicast_group);
1039 }
1040
l2tp_nl_cleanup(void)1041 static void l2tp_nl_cleanup(void)
1042 {
1043 genl_unregister_family(&l2tp_nl_family);
1044 }
1045
1046 module_init(l2tp_nl_init);
1047 module_exit(l2tp_nl_cleanup);
1048
1049 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1050 MODULE_DESCRIPTION("L2TP netlink");
1051 MODULE_LICENSE("GPL");
1052 MODULE_VERSION("1.0");
1053 MODULE_ALIAS_GENL_FAMILY("l2tp");
1054