1// SPDX-License-Identifier: GPL-2.0-only
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
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <net/sock.h>
16#include <net/genetlink.h>
17#include <net/udp.h>
18#include <linux/in.h>
19#include <linux/udp.h>
20#include <linux/socket.h>
21#include <linux/module.h>
22#include <linux/list.h>
23#include <net/net_namespace.h>
24
25#include <linux/l2tp.h>
26
27#include "l2tp_core.h"
28
29static struct genl_family l2tp_nl_family;
30
31static const struct genl_multicast_group l2tp_multicast_group[] = {
32 {
33 .name = L2TP_GENL_MCGROUP,
34 },
35};
36
37static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq,
38 int flags, struct l2tp_tunnel *tunnel, u8 cmd);
39static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq,
40 int flags, struct l2tp_session *session,
41 u8 cmd);
42
43/* Accessed under genl lock */
44static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
45
46static struct l2tp_session *l2tp_nl_session_get(struct genl_info *info)
47{
48 u32 tunnel_id;
49 u32 session_id;
50 char *ifname;
51 struct l2tp_tunnel *tunnel;
52 struct l2tp_session *session = NULL;
53 struct net *net = genl_info_net(info);
54
55 if (info->attrs[L2TP_ATTR_IFNAME]) {
56 ifname = nla_data(nla: info->attrs[L2TP_ATTR_IFNAME]);
57 session = l2tp_session_get_by_ifname(net, ifname);
58 } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
59 (info->attrs[L2TP_ATTR_CONN_ID])) {
60 tunnel_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_CONN_ID]);
61 session_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_SESSION_ID]);
62 tunnel = l2tp_tunnel_get(net, tunnel_id);
63 if (tunnel) {
64 session = l2tp_session_get(net, sk: tunnel->sock, pver: tunnel->version,
65 tunnel_id, session_id);
66 l2tp_tunnel_put(tunnel);
67 }
68 }
69
70 return session;
71}
72
73static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
74{
75 struct sk_buff *msg;
76 void *hdr;
77 int ret = -ENOBUFS;
78
79 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
80 if (!msg) {
81 ret = -ENOMEM;
82 goto out;
83 }
84
85 hdr = genlmsg_put(skb: msg, portid: info->snd_portid, seq: info->snd_seq,
86 family: &l2tp_nl_family, flags: 0, cmd: L2TP_CMD_NOOP);
87 if (!hdr) {
88 ret = -EMSGSIZE;
89 goto err_out;
90 }
91
92 genlmsg_end(skb: msg, hdr);
93
94 return genlmsg_unicast(net: genl_info_net(info), skb: msg, portid: info->snd_portid);
95
96err_out:
97 nlmsg_free(skb: msg);
98
99out:
100 return ret;
101}
102
103static int l2tp_tunnel_notify(struct genl_family *family,
104 struct genl_info *info,
105 struct l2tp_tunnel *tunnel,
106 u8 cmd)
107{
108 struct sk_buff *msg;
109 int ret;
110
111 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
112 if (!msg)
113 return -ENOMEM;
114
115 ret = l2tp_nl_tunnel_send(skb: msg, portid: info->snd_portid, seq: info->snd_seq,
116 NLM_F_ACK, tunnel, cmd);
117
118 if (ret >= 0) {
119 ret = genlmsg_multicast_allns(family, skb: msg, portid: 0, group: 0);
120 /* We don't care if no one is listening */
121 if (ret == -ESRCH)
122 ret = 0;
123 return ret;
124 }
125
126 nlmsg_free(skb: msg);
127
128 return ret;
129}
130
131static int l2tp_session_notify(struct genl_family *family,
132 struct genl_info *info,
133 struct l2tp_session *session,
134 u8 cmd)
135{
136 struct sk_buff *msg;
137 int ret;
138
139 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
140 if (!msg)
141 return -ENOMEM;
142
143 ret = l2tp_nl_session_send(skb: msg, portid: info->snd_portid, seq: info->snd_seq,
144 NLM_F_ACK, session, cmd);
145
146 if (ret >= 0) {
147 ret = genlmsg_multicast_allns(family, skb: msg, portid: 0, group: 0);
148 /* We don't care if no one is listening */
149 if (ret == -ESRCH)
150 ret = 0;
151 return ret;
152 }
153
154 nlmsg_free(skb: msg);
155
156 return ret;
157}
158
159static int l2tp_nl_cmd_tunnel_create_get_addr(struct nlattr **attrs, struct l2tp_tunnel_cfg *cfg)
160{
161 if (attrs[L2TP_ATTR_UDP_SPORT])
162 cfg->local_udp_port = nla_get_u16(nla: attrs[L2TP_ATTR_UDP_SPORT]);
163 if (attrs[L2TP_ATTR_UDP_DPORT])
164 cfg->peer_udp_port = nla_get_u16(nla: attrs[L2TP_ATTR_UDP_DPORT]);
165 cfg->use_udp_checksums = nla_get_flag(nla: attrs[L2TP_ATTR_UDP_CSUM]);
166
167 /* Must have either AF_INET or AF_INET6 address for source and destination */
168#if IS_ENABLED(CONFIG_IPV6)
169 if (attrs[L2TP_ATTR_IP6_SADDR] && attrs[L2TP_ATTR_IP6_DADDR]) {
170 cfg->local_ip6 = nla_data(nla: attrs[L2TP_ATTR_IP6_SADDR]);
171 cfg->peer_ip6 = nla_data(nla: attrs[L2TP_ATTR_IP6_DADDR]);
172 cfg->udp6_zero_tx_checksums = nla_get_flag(nla: attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
173 cfg->udp6_zero_rx_checksums = nla_get_flag(nla: attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
174 return 0;
175 }
176#endif
177 if (attrs[L2TP_ATTR_IP_SADDR] && attrs[L2TP_ATTR_IP_DADDR]) {
178 cfg->local_ip.s_addr = nla_get_in_addr(nla: attrs[L2TP_ATTR_IP_SADDR]);
179 cfg->peer_ip.s_addr = nla_get_in_addr(nla: attrs[L2TP_ATTR_IP_DADDR]);
180 return 0;
181 }
182 return -EINVAL;
183}
184
185static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
186{
187 u32 tunnel_id;
188 u32 peer_tunnel_id;
189 int proto_version;
190 int fd = -1;
191 int ret = 0;
192 struct l2tp_tunnel_cfg cfg = { 0, };
193 struct l2tp_tunnel *tunnel;
194 struct net *net = genl_info_net(info);
195 struct nlattr **attrs = info->attrs;
196
197 if (!attrs[L2TP_ATTR_CONN_ID]) {
198 ret = -EINVAL;
199 goto out;
200 }
201 tunnel_id = nla_get_u32(nla: attrs[L2TP_ATTR_CONN_ID]);
202
203 if (!attrs[L2TP_ATTR_PEER_CONN_ID]) {
204 ret = -EINVAL;
205 goto out;
206 }
207 peer_tunnel_id = nla_get_u32(nla: attrs[L2TP_ATTR_PEER_CONN_ID]);
208
209 if (!attrs[L2TP_ATTR_PROTO_VERSION]) {
210 ret = -EINVAL;
211 goto out;
212 }
213 proto_version = nla_get_u8(nla: attrs[L2TP_ATTR_PROTO_VERSION]);
214
215 if (!attrs[L2TP_ATTR_ENCAP_TYPE]) {
216 ret = -EINVAL;
217 goto out;
218 }
219 cfg.encap = nla_get_u16(nla: attrs[L2TP_ATTR_ENCAP_TYPE]);
220
221 /* Managed tunnels take the tunnel socket from userspace.
222 * Unmanaged tunnels must call out the source and destination addresses
223 * for the kernel to create the tunnel socket itself.
224 */
225 if (attrs[L2TP_ATTR_FD]) {
226 fd = nla_get_u32(nla: attrs[L2TP_ATTR_FD]);
227 } else {
228 ret = l2tp_nl_cmd_tunnel_create_get_addr(attrs, cfg: &cfg);
229 if (ret < 0)
230 goto out;
231 }
232
233 ret = -EINVAL;
234 switch (cfg.encap) {
235 case L2TP_ENCAPTYPE_UDP:
236 case L2TP_ENCAPTYPE_IP:
237 ret = l2tp_tunnel_create(fd, version: proto_version, tunnel_id,
238 peer_tunnel_id, cfg: &cfg, tunnelp: &tunnel);
239 break;
240 }
241
242 if (ret < 0)
243 goto out;
244
245 refcount_inc(r: &tunnel->ref_count);
246 ret = l2tp_tunnel_register(tunnel, net, cfg: &cfg);
247 if (ret < 0) {
248 kfree(objp: tunnel);
249 goto out;
250 }
251 ret = l2tp_tunnel_notify(family: &l2tp_nl_family, info, tunnel,
252 cmd: L2TP_CMD_TUNNEL_CREATE);
253 l2tp_tunnel_put(tunnel);
254
255out:
256 return ret;
257}
258
259static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
260{
261 struct l2tp_tunnel *tunnel;
262 u32 tunnel_id;
263 int ret = 0;
264 struct net *net = genl_info_net(info);
265
266 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
267 ret = -EINVAL;
268 goto out;
269 }
270 tunnel_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_CONN_ID]);
271
272 tunnel = l2tp_tunnel_get(net, tunnel_id);
273 if (!tunnel) {
274 ret = -ENODEV;
275 goto out;
276 }
277
278 l2tp_tunnel_notify(family: &l2tp_nl_family, info,
279 tunnel, cmd: L2TP_CMD_TUNNEL_DELETE);
280
281 l2tp_tunnel_delete(tunnel);
282
283 l2tp_tunnel_put(tunnel);
284
285out:
286 return ret;
287}
288
289static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
290{
291 struct l2tp_tunnel *tunnel;
292 u32 tunnel_id;
293 int ret = 0;
294 struct net *net = genl_info_net(info);
295
296 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
297 ret = -EINVAL;
298 goto out;
299 }
300 tunnel_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_CONN_ID]);
301
302 tunnel = l2tp_tunnel_get(net, tunnel_id);
303 if (!tunnel) {
304 ret = -ENODEV;
305 goto out;
306 }
307
308 ret = l2tp_tunnel_notify(family: &l2tp_nl_family, info,
309 tunnel, cmd: L2TP_CMD_TUNNEL_MODIFY);
310
311 l2tp_tunnel_put(tunnel);
312
313out:
314 return ret;
315}
316
317#if IS_ENABLED(CONFIG_IPV6)
318static int l2tp_nl_tunnel_send_addr6(struct sk_buff *skb, struct sock *sk,
319 enum l2tp_encap_type encap)
320{
321 struct inet_sock *inet = inet_sk(sk);
322 struct ipv6_pinfo *np = inet6_sk(sk: sk);
323
324 switch (encap) {
325 case L2TP_ENCAPTYPE_UDP:
326 if (udp_get_no_check6_tx(sk) &&
327 nla_put_flag(skb, attrtype: L2TP_ATTR_UDP_ZERO_CSUM6_TX))
328 return -1;
329 if (udp_get_no_check6_rx(sk) &&
330 nla_put_flag(skb, attrtype: L2TP_ATTR_UDP_ZERO_CSUM6_RX))
331 return -1;
332 if (nla_put_u16(skb, attrtype: L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
333 nla_put_u16(skb, attrtype: L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
334 return -1;
335 fallthrough;
336 case L2TP_ENCAPTYPE_IP:
337 if (nla_put_in6_addr(skb, attrtype: L2TP_ATTR_IP6_SADDR, addr: &np->saddr) ||
338 nla_put_in6_addr(skb, attrtype: L2TP_ATTR_IP6_DADDR, addr: &sk->sk_v6_daddr))
339 return -1;
340 break;
341 }
342 return 0;
343}
344#endif
345
346static int l2tp_nl_tunnel_send_addr4(struct sk_buff *skb, struct sock *sk,
347 enum l2tp_encap_type encap)
348{
349 struct inet_sock *inet = inet_sk(sk);
350
351 switch (encap) {
352 case L2TP_ENCAPTYPE_UDP:
353 if (nla_put_u8(skb, attrtype: L2TP_ATTR_UDP_CSUM, value: !sk->sk_no_check_tx) ||
354 nla_put_u16(skb, attrtype: L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
355 nla_put_u16(skb, attrtype: L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
356 return -1;
357 fallthrough;
358 case L2TP_ENCAPTYPE_IP:
359 if (nla_put_in_addr(skb, attrtype: L2TP_ATTR_IP_SADDR, addr: inet->inet_saddr) ||
360 nla_put_in_addr(skb, attrtype: L2TP_ATTR_IP_DADDR, addr: inet->inet_daddr))
361 return -1;
362 break;
363 }
364
365 return 0;
366}
367
368/* Append attributes for the tunnel address, handling the different attribute types
369 * used for different tunnel encapsulation and AF_INET v.s. AF_INET6.
370 */
371static int l2tp_nl_tunnel_send_addr(struct sk_buff *skb, struct l2tp_tunnel *tunnel)
372{
373 struct sock *sk = tunnel->sock;
374
375 if (!sk)
376 return 0;
377
378#if IS_ENABLED(CONFIG_IPV6)
379 if (sk->sk_family == AF_INET6)
380 return l2tp_nl_tunnel_send_addr6(skb, sk, encap: tunnel->encap);
381#endif
382 return l2tp_nl_tunnel_send_addr4(skb, sk, encap: tunnel->encap);
383}
384
385static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
386 struct l2tp_tunnel *tunnel, u8 cmd)
387{
388 void *hdr;
389 struct nlattr *nest;
390
391 hdr = genlmsg_put(skb, portid, seq, family: &l2tp_nl_family, flags, cmd);
392 if (!hdr)
393 return -EMSGSIZE;
394
395 if (nla_put_u8(skb, attrtype: L2TP_ATTR_PROTO_VERSION, value: tunnel->version) ||
396 nla_put_u32(skb, attrtype: L2TP_ATTR_CONN_ID, value: tunnel->tunnel_id) ||
397 nla_put_u32(skb, attrtype: L2TP_ATTR_PEER_CONN_ID, value: tunnel->peer_tunnel_id) ||
398 nla_put_u32(skb, attrtype: L2TP_ATTR_DEBUG, value: 0) ||
399 nla_put_u16(skb, attrtype: L2TP_ATTR_ENCAP_TYPE, value: tunnel->encap))
400 goto nla_put_failure;
401
402 nest = nla_nest_start_noflag(skb, attrtype: L2TP_ATTR_STATS);
403 if (!nest)
404 goto nla_put_failure;
405
406 if (nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_TX_PACKETS,
407 value: atomic_long_read(v: &tunnel->stats.tx_packets),
408 padattr: L2TP_ATTR_STATS_PAD) ||
409 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_TX_BYTES,
410 value: atomic_long_read(v: &tunnel->stats.tx_bytes),
411 padattr: L2TP_ATTR_STATS_PAD) ||
412 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_TX_ERRORS,
413 value: atomic_long_read(v: &tunnel->stats.tx_errors),
414 padattr: L2TP_ATTR_STATS_PAD) ||
415 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_PACKETS,
416 value: atomic_long_read(v: &tunnel->stats.rx_packets),
417 padattr: L2TP_ATTR_STATS_PAD) ||
418 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_BYTES,
419 value: atomic_long_read(v: &tunnel->stats.rx_bytes),
420 padattr: L2TP_ATTR_STATS_PAD) ||
421 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_SEQ_DISCARDS,
422 value: atomic_long_read(v: &tunnel->stats.rx_seq_discards),
423 padattr: L2TP_ATTR_STATS_PAD) ||
424 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_COOKIE_DISCARDS,
425 value: atomic_long_read(v: &tunnel->stats.rx_cookie_discards),
426 padattr: L2TP_ATTR_STATS_PAD) ||
427 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_OOS_PACKETS,
428 value: atomic_long_read(v: &tunnel->stats.rx_oos_packets),
429 padattr: L2TP_ATTR_STATS_PAD) ||
430 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_ERRORS,
431 value: atomic_long_read(v: &tunnel->stats.rx_errors),
432 padattr: L2TP_ATTR_STATS_PAD) ||
433 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_INVALID,
434 value: atomic_long_read(v: &tunnel->stats.rx_invalid),
435 padattr: L2TP_ATTR_STATS_PAD))
436 goto nla_put_failure;
437 nla_nest_end(skb, start: nest);
438
439 if (l2tp_nl_tunnel_send_addr(skb, tunnel))
440 goto nla_put_failure;
441
442 genlmsg_end(skb, hdr);
443 return 0;
444
445nla_put_failure:
446 genlmsg_cancel(skb, hdr);
447 return -1;
448}
449
450static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
451{
452 struct l2tp_tunnel *tunnel;
453 struct sk_buff *msg;
454 u32 tunnel_id;
455 int ret = -ENOBUFS;
456 struct net *net = genl_info_net(info);
457
458 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
459 ret = -EINVAL;
460 goto err;
461 }
462
463 tunnel_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_CONN_ID]);
464
465 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
466 if (!msg) {
467 ret = -ENOMEM;
468 goto err;
469 }
470
471 tunnel = l2tp_tunnel_get(net, tunnel_id);
472 if (!tunnel) {
473 ret = -ENODEV;
474 goto err_nlmsg;
475 }
476
477 ret = l2tp_nl_tunnel_send(skb: msg, portid: info->snd_portid, seq: info->snd_seq,
478 NLM_F_ACK, tunnel, cmd: L2TP_CMD_TUNNEL_GET);
479 if (ret < 0)
480 goto err_nlmsg_tunnel;
481
482 l2tp_tunnel_put(tunnel);
483
484 return genlmsg_unicast(net, skb: msg, portid: info->snd_portid);
485
486err_nlmsg_tunnel:
487 l2tp_tunnel_put(tunnel);
488err_nlmsg:
489 nlmsg_free(skb: msg);
490err:
491 return ret;
492}
493
494struct l2tp_nl_cb_data {
495 unsigned long tkey;
496 unsigned long skey;
497};
498
499static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
500{
501 struct l2tp_nl_cb_data *cbd = (void *)&cb->ctx[0];
502 unsigned long key = cbd->tkey;
503 struct l2tp_tunnel *tunnel;
504 struct net *net = sock_net(sk: skb->sk);
505
506 for (;;) {
507 tunnel = l2tp_tunnel_get_next(net, key: &key);
508 if (!tunnel)
509 goto out;
510
511 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
512 seq: cb->nlh->nlmsg_seq, NLM_F_MULTI,
513 tunnel, cmd: L2TP_CMD_TUNNEL_GET) < 0) {
514 l2tp_tunnel_put(tunnel);
515 goto out;
516 }
517 l2tp_tunnel_put(tunnel);
518
519 key++;
520 }
521
522out:
523 cbd->tkey = key;
524
525 return skb->len;
526}
527
528static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
529{
530 u32 tunnel_id = 0;
531 u32 session_id;
532 u32 peer_session_id;
533 int ret = 0;
534 struct l2tp_tunnel *tunnel;
535 struct l2tp_session *session;
536 struct l2tp_session_cfg cfg = { 0, };
537 struct net *net = genl_info_net(info);
538
539 if (!info->attrs[L2TP_ATTR_CONN_ID]) {
540 ret = -EINVAL;
541 goto out;
542 }
543
544 tunnel_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_CONN_ID]);
545 tunnel = l2tp_tunnel_get(net, tunnel_id);
546 if (!tunnel) {
547 ret = -ENODEV;
548 goto out;
549 }
550
551 if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
552 ret = -EINVAL;
553 goto out_tunnel;
554 }
555 session_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_SESSION_ID]);
556
557 if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
558 ret = -EINVAL;
559 goto out_tunnel;
560 }
561 peer_session_id = nla_get_u32(nla: info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
562
563 if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
564 ret = -EINVAL;
565 goto out_tunnel;
566 }
567 cfg.pw_type = nla_get_u16(nla: info->attrs[L2TP_ATTR_PW_TYPE]);
568 if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
569 ret = -EINVAL;
570 goto out_tunnel;
571 }
572
573 /* L2TPv2 only accepts PPP pseudo-wires */
574 if (tunnel->version == 2 && cfg.pw_type != L2TP_PWTYPE_PPP) {
575 ret = -EPROTONOSUPPORT;
576 goto out_tunnel;
577 }
578
579 if (tunnel->version > 2) {
580 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE]) {
581 cfg.l2specific_type = nla_get_u8(nla: info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
582 if (cfg.l2specific_type != L2TP_L2SPECTYPE_DEFAULT &&
583 cfg.l2specific_type != L2TP_L2SPECTYPE_NONE) {
584 ret = -EINVAL;
585 goto out_tunnel;
586 }
587 } else {
588 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
589 }
590
591 if (info->attrs[L2TP_ATTR_COOKIE]) {
592 u16 len = nla_len(nla: info->attrs[L2TP_ATTR_COOKIE]);
593
594 if (len > 8) {
595 ret = -EINVAL;
596 goto out_tunnel;
597 }
598 cfg.cookie_len = len;
599 memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
600 }
601 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
602 u16 len = nla_len(nla: info->attrs[L2TP_ATTR_PEER_COOKIE]);
603
604 if (len > 8) {
605 ret = -EINVAL;
606 goto out_tunnel;
607 }
608 cfg.peer_cookie_len = len;
609 memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
610 }
611 if (info->attrs[L2TP_ATTR_IFNAME])
612 cfg.ifname = nla_data(nla: info->attrs[L2TP_ATTR_IFNAME]);
613 }
614
615 if (info->attrs[L2TP_ATTR_RECV_SEQ])
616 cfg.recv_seq = nla_get_u8(nla: info->attrs[L2TP_ATTR_RECV_SEQ]);
617
618 if (info->attrs[L2TP_ATTR_SEND_SEQ])
619 cfg.send_seq = nla_get_u8(nla: info->attrs[L2TP_ATTR_SEND_SEQ]);
620
621 if (info->attrs[L2TP_ATTR_LNS_MODE])
622 cfg.lns_mode = nla_get_u8(nla: info->attrs[L2TP_ATTR_LNS_MODE]);
623
624 if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
625 cfg.reorder_timeout = nla_get_msecs(nla: info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
626
627#ifdef CONFIG_MODULES
628 if (!l2tp_nl_cmd_ops[cfg.pw_type]) {
629 genl_unlock();
630 request_module("net-l2tp-type-%u", cfg.pw_type);
631 genl_lock();
632 }
633#endif
634 if (!l2tp_nl_cmd_ops[cfg.pw_type] || !l2tp_nl_cmd_ops[cfg.pw_type]->session_create) {
635 ret = -EPROTONOSUPPORT;
636 goto out_tunnel;
637 }
638
639 ret = l2tp_nl_cmd_ops[cfg.pw_type]->session_create(net, tunnel,
640 session_id,
641 peer_session_id,
642 &cfg);
643
644 if (ret >= 0) {
645 session = l2tp_session_get(net, sk: tunnel->sock, pver: tunnel->version,
646 tunnel_id, session_id);
647 if (session) {
648 ret = l2tp_session_notify(family: &l2tp_nl_family, info, session,
649 cmd: L2TP_CMD_SESSION_CREATE);
650 l2tp_session_put(session);
651 }
652 }
653
654out_tunnel:
655 l2tp_tunnel_put(tunnel);
656out:
657 return ret;
658}
659
660static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
661{
662 int ret = 0;
663 struct l2tp_session *session;
664 u16 pw_type;
665
666 session = l2tp_nl_session_get(info);
667 if (!session) {
668 ret = -ENODEV;
669 goto out;
670 }
671
672 l2tp_session_notify(family: &l2tp_nl_family, info,
673 session, cmd: L2TP_CMD_SESSION_DELETE);
674
675 pw_type = session->pwtype;
676 if (pw_type < __L2TP_PWTYPE_MAX)
677 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
678 l2tp_nl_cmd_ops[pw_type]->session_delete(session);
679
680 l2tp_session_put(session);
681
682out:
683 return ret;
684}
685
686static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
687{
688 int ret = 0;
689 struct l2tp_session *session;
690
691 session = l2tp_nl_session_get(info);
692 if (!session) {
693 ret = -ENODEV;
694 goto out;
695 }
696
697 if (info->attrs[L2TP_ATTR_RECV_SEQ])
698 session->recv_seq = nla_get_u8(nla: info->attrs[L2TP_ATTR_RECV_SEQ]);
699
700 if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
701 struct l2tp_tunnel *tunnel = session->tunnel;
702
703 session->send_seq = nla_get_u8(nla: info->attrs[L2TP_ATTR_SEND_SEQ]);
704 l2tp_session_set_header_len(session, version: tunnel->version, encap: tunnel->encap);
705 }
706
707 if (info->attrs[L2TP_ATTR_LNS_MODE])
708 session->lns_mode = nla_get_u8(nla: info->attrs[L2TP_ATTR_LNS_MODE]);
709
710 if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
711 session->reorder_timeout = nla_get_msecs(nla: info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
712
713 ret = l2tp_session_notify(family: &l2tp_nl_family, info,
714 session, cmd: L2TP_CMD_SESSION_MODIFY);
715
716 l2tp_session_put(session);
717
718out:
719 return ret;
720}
721
722static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
723 struct l2tp_session *session, u8 cmd)
724{
725 void *hdr;
726 struct nlattr *nest;
727 struct l2tp_tunnel *tunnel = session->tunnel;
728
729 hdr = genlmsg_put(skb, portid, seq, family: &l2tp_nl_family, flags, cmd);
730 if (!hdr)
731 return -EMSGSIZE;
732
733 if (nla_put_u32(skb, attrtype: L2TP_ATTR_CONN_ID, value: tunnel->tunnel_id) ||
734 nla_put_u32(skb, attrtype: L2TP_ATTR_SESSION_ID, value: session->session_id) ||
735 nla_put_u32(skb, attrtype: L2TP_ATTR_PEER_CONN_ID, value: tunnel->peer_tunnel_id) ||
736 nla_put_u32(skb, attrtype: L2TP_ATTR_PEER_SESSION_ID, value: session->peer_session_id) ||
737 nla_put_u32(skb, attrtype: L2TP_ATTR_DEBUG, value: 0) ||
738 nla_put_u16(skb, attrtype: L2TP_ATTR_PW_TYPE, value: session->pwtype))
739 goto nla_put_failure;
740
741 if ((session->ifname[0] &&
742 nla_put_string(skb, attrtype: L2TP_ATTR_IFNAME, str: session->ifname)) ||
743 (session->cookie_len &&
744 nla_put(skb, attrtype: L2TP_ATTR_COOKIE, attrlen: session->cookie_len, data: session->cookie)) ||
745 (session->peer_cookie_len &&
746 nla_put(skb, attrtype: L2TP_ATTR_PEER_COOKIE, attrlen: session->peer_cookie_len, data: session->peer_cookie)) ||
747 nla_put_u8(skb, attrtype: L2TP_ATTR_RECV_SEQ, value: session->recv_seq) ||
748 nla_put_u8(skb, attrtype: L2TP_ATTR_SEND_SEQ, value: session->send_seq) ||
749 nla_put_u8(skb, attrtype: L2TP_ATTR_LNS_MODE, value: session->lns_mode) ||
750 (l2tp_tunnel_uses_xfrm(tunnel) &&
751 nla_put_u8(skb, attrtype: L2TP_ATTR_USING_IPSEC, value: 1)) ||
752 (session->reorder_timeout &&
753 nla_put_msecs(skb, attrtype: L2TP_ATTR_RECV_TIMEOUT,
754 njiffies: session->reorder_timeout, padattr: L2TP_ATTR_PAD)))
755 goto nla_put_failure;
756
757 nest = nla_nest_start_noflag(skb, attrtype: L2TP_ATTR_STATS);
758 if (!nest)
759 goto nla_put_failure;
760
761 if (nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_TX_PACKETS,
762 value: atomic_long_read(v: &session->stats.tx_packets),
763 padattr: L2TP_ATTR_STATS_PAD) ||
764 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_TX_BYTES,
765 value: atomic_long_read(v: &session->stats.tx_bytes),
766 padattr: L2TP_ATTR_STATS_PAD) ||
767 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_TX_ERRORS,
768 value: atomic_long_read(v: &session->stats.tx_errors),
769 padattr: L2TP_ATTR_STATS_PAD) ||
770 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_PACKETS,
771 value: atomic_long_read(v: &session->stats.rx_packets),
772 padattr: L2TP_ATTR_STATS_PAD) ||
773 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_BYTES,
774 value: atomic_long_read(v: &session->stats.rx_bytes),
775 padattr: L2TP_ATTR_STATS_PAD) ||
776 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_SEQ_DISCARDS,
777 value: atomic_long_read(v: &session->stats.rx_seq_discards),
778 padattr: L2TP_ATTR_STATS_PAD) ||
779 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_COOKIE_DISCARDS,
780 value: atomic_long_read(v: &session->stats.rx_cookie_discards),
781 padattr: L2TP_ATTR_STATS_PAD) ||
782 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_OOS_PACKETS,
783 value: atomic_long_read(v: &session->stats.rx_oos_packets),
784 padattr: L2TP_ATTR_STATS_PAD) ||
785 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_ERRORS,
786 value: atomic_long_read(v: &session->stats.rx_errors),
787 padattr: L2TP_ATTR_STATS_PAD) ||
788 nla_put_u64_64bit(skb, attrtype: L2TP_ATTR_RX_INVALID,
789 value: atomic_long_read(v: &session->stats.rx_invalid),
790 padattr: L2TP_ATTR_STATS_PAD))
791 goto nla_put_failure;
792 nla_nest_end(skb, start: nest);
793
794 genlmsg_end(skb, hdr);
795 return 0;
796
797 nla_put_failure:
798 genlmsg_cancel(skb, hdr);
799 return -1;
800}
801
802static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
803{
804 struct l2tp_session *session;
805 struct sk_buff *msg;
806 int ret;
807
808 session = l2tp_nl_session_get(info);
809 if (!session) {
810 ret = -ENODEV;
811 goto err;
812 }
813
814 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
815 if (!msg) {
816 ret = -ENOMEM;
817 goto err_ref;
818 }
819
820 ret = l2tp_nl_session_send(skb: msg, portid: info->snd_portid, seq: info->snd_seq,
821 flags: 0, session, cmd: L2TP_CMD_SESSION_GET);
822 if (ret < 0)
823 goto err_ref_msg;
824
825 ret = genlmsg_unicast(net: genl_info_net(info), skb: msg, portid: info->snd_portid);
826
827 l2tp_session_put(session);
828
829 return ret;
830
831err_ref_msg:
832 nlmsg_free(skb: msg);
833err_ref:
834 l2tp_session_put(session);
835err:
836 return ret;
837}
838
839static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
840{
841 struct l2tp_nl_cb_data *cbd = (void *)&cb->ctx[0];
842 struct net *net = sock_net(sk: skb->sk);
843 struct l2tp_session *session;
844 struct l2tp_tunnel *tunnel = NULL;
845 unsigned long tkey = cbd->tkey;
846 unsigned long skey = cbd->skey;
847
848 for (;;) {
849 if (!tunnel) {
850 tunnel = l2tp_tunnel_get_next(net, key: &tkey);
851 if (!tunnel)
852 goto out;
853 }
854
855 session = l2tp_session_get_next(net, sk: tunnel->sock, pver: tunnel->version,
856 tunnel_id: tunnel->tunnel_id, key: &skey);
857 if (!session) {
858 tkey++;
859 l2tp_tunnel_put(tunnel);
860 tunnel = NULL;
861 skey = 0;
862 continue;
863 }
864
865 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
866 seq: cb->nlh->nlmsg_seq, NLM_F_MULTI,
867 session, cmd: L2TP_CMD_SESSION_GET) < 0) {
868 l2tp_session_put(session);
869 l2tp_tunnel_put(tunnel);
870 break;
871 }
872 l2tp_session_put(session);
873
874 skey++;
875 }
876
877out:
878 cbd->tkey = tkey;
879 cbd->skey = skey;
880
881 return skb->len;
882}
883
884static const struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
885 [L2TP_ATTR_NONE] = { .type = NLA_UNSPEC, },
886 [L2TP_ATTR_PW_TYPE] = { .type = NLA_U16, },
887 [L2TP_ATTR_ENCAP_TYPE] = { .type = NLA_U16, },
888 [L2TP_ATTR_OFFSET] = { .type = NLA_U16, },
889 [L2TP_ATTR_DATA_SEQ] = { .type = NLA_U8, },
890 [L2TP_ATTR_L2SPEC_TYPE] = { .type = NLA_U8, },
891 [L2TP_ATTR_L2SPEC_LEN] = { .type = NLA_U8, },
892 [L2TP_ATTR_PROTO_VERSION] = { .type = NLA_U8, },
893 [L2TP_ATTR_CONN_ID] = { .type = NLA_U32, },
894 [L2TP_ATTR_PEER_CONN_ID] = { .type = NLA_U32, },
895 [L2TP_ATTR_SESSION_ID] = { .type = NLA_U32, },
896 [L2TP_ATTR_PEER_SESSION_ID] = { .type = NLA_U32, },
897 [L2TP_ATTR_UDP_CSUM] = { .type = NLA_U8, },
898 [L2TP_ATTR_VLAN_ID] = { .type = NLA_U16, },
899 [L2TP_ATTR_DEBUG] = { .type = NLA_U32, },
900 [L2TP_ATTR_RECV_SEQ] = { .type = NLA_U8, },
901 [L2TP_ATTR_SEND_SEQ] = { .type = NLA_U8, },
902 [L2TP_ATTR_LNS_MODE] = { .type = NLA_U8, },
903 [L2TP_ATTR_USING_IPSEC] = { .type = NLA_U8, },
904 [L2TP_ATTR_RECV_TIMEOUT] = { .type = NLA_MSECS, },
905 [L2TP_ATTR_FD] = { .type = NLA_U32, },
906 [L2TP_ATTR_IP_SADDR] = { .type = NLA_U32, },
907 [L2TP_ATTR_IP_DADDR] = { .type = NLA_U32, },
908 [L2TP_ATTR_UDP_SPORT] = { .type = NLA_U16, },
909 [L2TP_ATTR_UDP_DPORT] = { .type = NLA_U16, },
910 [L2TP_ATTR_MTU] = { .type = NLA_U16, },
911 [L2TP_ATTR_MRU] = { .type = NLA_U16, },
912 [L2TP_ATTR_STATS] = { .type = NLA_NESTED, },
913 [L2TP_ATTR_IP6_SADDR] = {
914 .type = NLA_BINARY,
915 .len = sizeof(struct in6_addr),
916 },
917 [L2TP_ATTR_IP6_DADDR] = {
918 .type = NLA_BINARY,
919 .len = sizeof(struct in6_addr),
920 },
921 [L2TP_ATTR_IFNAME] = {
922 .type = NLA_NUL_STRING,
923 .len = IFNAMSIZ - 1,
924 },
925 [L2TP_ATTR_COOKIE] = {
926 .type = NLA_BINARY,
927 .len = 8,
928 },
929 [L2TP_ATTR_PEER_COOKIE] = {
930 .type = NLA_BINARY,
931 .len = 8,
932 },
933};
934
935static const struct genl_small_ops l2tp_nl_ops[] = {
936 {
937 .cmd = L2TP_CMD_NOOP,
938 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
939 .doit = l2tp_nl_cmd_noop,
940 /* can be retrieved by unprivileged users */
941 },
942 {
943 .cmd = L2TP_CMD_TUNNEL_CREATE,
944 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
945 .doit = l2tp_nl_cmd_tunnel_create,
946 .flags = GENL_UNS_ADMIN_PERM,
947 },
948 {
949 .cmd = L2TP_CMD_TUNNEL_DELETE,
950 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
951 .doit = l2tp_nl_cmd_tunnel_delete,
952 .flags = GENL_UNS_ADMIN_PERM,
953 },
954 {
955 .cmd = L2TP_CMD_TUNNEL_MODIFY,
956 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
957 .doit = l2tp_nl_cmd_tunnel_modify,
958 .flags = GENL_UNS_ADMIN_PERM,
959 },
960 {
961 .cmd = L2TP_CMD_TUNNEL_GET,
962 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
963 .doit = l2tp_nl_cmd_tunnel_get,
964 .dumpit = l2tp_nl_cmd_tunnel_dump,
965 .flags = GENL_UNS_ADMIN_PERM,
966 },
967 {
968 .cmd = L2TP_CMD_SESSION_CREATE,
969 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
970 .doit = l2tp_nl_cmd_session_create,
971 .flags = GENL_UNS_ADMIN_PERM,
972 },
973 {
974 .cmd = L2TP_CMD_SESSION_DELETE,
975 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
976 .doit = l2tp_nl_cmd_session_delete,
977 .flags = GENL_UNS_ADMIN_PERM,
978 },
979 {
980 .cmd = L2TP_CMD_SESSION_MODIFY,
981 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
982 .doit = l2tp_nl_cmd_session_modify,
983 .flags = GENL_UNS_ADMIN_PERM,
984 },
985 {
986 .cmd = L2TP_CMD_SESSION_GET,
987 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
988 .doit = l2tp_nl_cmd_session_get,
989 .dumpit = l2tp_nl_cmd_session_dump,
990 .flags = GENL_UNS_ADMIN_PERM,
991 },
992};
993
994static struct genl_family l2tp_nl_family __ro_after_init = {
995 .name = L2TP_GENL_NAME,
996 .version = L2TP_GENL_VERSION,
997 .hdrsize = 0,
998 .maxattr = L2TP_ATTR_MAX,
999 .policy = l2tp_nl_policy,
1000 .netnsok = true,
1001 .module = THIS_MODULE,
1002 .small_ops = l2tp_nl_ops,
1003 .n_small_ops = ARRAY_SIZE(l2tp_nl_ops),
1004 .resv_start_op = L2TP_CMD_SESSION_GET + 1,
1005 .mcgrps = l2tp_multicast_group,
1006 .n_mcgrps = ARRAY_SIZE(l2tp_multicast_group),
1007};
1008
1009int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
1010{
1011 int ret;
1012
1013 ret = -EINVAL;
1014 if (pw_type >= __L2TP_PWTYPE_MAX)
1015 goto err;
1016
1017 genl_lock();
1018 ret = -EBUSY;
1019 if (l2tp_nl_cmd_ops[pw_type])
1020 goto out;
1021
1022 l2tp_nl_cmd_ops[pw_type] = ops;
1023 ret = 0;
1024
1025out:
1026 genl_unlock();
1027err:
1028 return ret;
1029}
1030EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
1031
1032void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
1033{
1034 if (pw_type < __L2TP_PWTYPE_MAX) {
1035 genl_lock();
1036 l2tp_nl_cmd_ops[pw_type] = NULL;
1037 genl_unlock();
1038 }
1039}
1040EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
1041
1042static int __init l2tp_nl_init(void)
1043{
1044 pr_info("L2TP netlink interface\n");
1045 return genl_register_family(family: &l2tp_nl_family);
1046}
1047
1048static void l2tp_nl_cleanup(void)
1049{
1050 genl_unregister_family(family: &l2tp_nl_family);
1051}
1052
1053module_init(l2tp_nl_init);
1054module_exit(l2tp_nl_cleanup);
1055
1056MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1057MODULE_DESCRIPTION("L2TP netlink");
1058MODULE_LICENSE("GPL");
1059MODULE_VERSION("1.0");
1060MODULE_ALIAS_GENL_FAMILY("l2tp");
1061

source code of linux/net/l2tp/l2tp_netlink.c