l2tp: fix a lockdep splat
[linux-3.10.git] / net / l2tp / l2tp_netlink.c
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 };
41
42 /* Accessed under genl lock */
43 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
44
45 static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info)
46 {
47         u32 tunnel_id;
48         u32 session_id;
49         char *ifname;
50         struct l2tp_tunnel *tunnel;
51         struct l2tp_session *session = NULL;
52         struct net *net = genl_info_net(info);
53
54         if (info->attrs[L2TP_ATTR_IFNAME]) {
55                 ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
56                 session = l2tp_session_find_by_ifname(net, ifname);
57         } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
58                    (info->attrs[L2TP_ATTR_CONN_ID])) {
59                 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
60                 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
61                 tunnel = l2tp_tunnel_find(net, tunnel_id);
62                 if (tunnel)
63                         session = l2tp_session_find(net, tunnel, session_id);
64         }
65
66         return session;
67 }
68
69 static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
70 {
71         struct sk_buff *msg;
72         void *hdr;
73         int ret = -ENOBUFS;
74
75         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
76         if (!msg) {
77                 ret = -ENOMEM;
78                 goto out;
79         }
80
81         hdr = genlmsg_put(msg, info->snd_pid, info->snd_seq,
82                           &l2tp_nl_family, 0, L2TP_CMD_NOOP);
83         if (IS_ERR(hdr)) {
84                 ret = PTR_ERR(hdr);
85                 goto err_out;
86         }
87
88         genlmsg_end(msg, hdr);
89
90         return genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
91
92 err_out:
93         nlmsg_free(msg);
94
95 out:
96         return ret;
97 }
98
99 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
100 {
101         u32 tunnel_id;
102         u32 peer_tunnel_id;
103         int proto_version;
104         int fd;
105         int ret = 0;
106         struct l2tp_tunnel_cfg cfg = { 0, };
107         struct l2tp_tunnel *tunnel;
108         struct net *net = genl_info_net(info);
109
110         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
111                 ret = -EINVAL;
112                 goto out;
113         }
114         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
115
116         if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
117                 ret = -EINVAL;
118                 goto out;
119         }
120         peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
121
122         if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
123                 ret = -EINVAL;
124                 goto out;
125         }
126         proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
127
128         if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
129                 ret = -EINVAL;
130                 goto out;
131         }
132         cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
133
134         fd = -1;
135         if (info->attrs[L2TP_ATTR_FD]) {
136                 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
137         } else {
138 #if IS_ENABLED(CONFIG_IPV6)
139                 if (info->attrs[L2TP_ATTR_IP6_SADDR] &&
140                     info->attrs[L2TP_ATTR_IP6_DADDR]) {
141                         cfg.local_ip6 = nla_data(
142                                 info->attrs[L2TP_ATTR_IP6_SADDR]);
143                         cfg.peer_ip6 = nla_data(
144                                 info->attrs[L2TP_ATTR_IP6_DADDR]);
145                 } else
146 #endif
147                 if (info->attrs[L2TP_ATTR_IP_SADDR] &&
148                     info->attrs[L2TP_ATTR_IP_DADDR]) {
149                         cfg.local_ip.s_addr = nla_get_be32(
150                                 info->attrs[L2TP_ATTR_IP_SADDR]);
151                         cfg.peer_ip.s_addr = nla_get_be32(
152                                 info->attrs[L2TP_ATTR_IP_DADDR]);
153                 } else {
154                         ret = -EINVAL;
155                         goto out;
156                 }
157                 if (info->attrs[L2TP_ATTR_UDP_SPORT])
158                         cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
159                 if (info->attrs[L2TP_ATTR_UDP_DPORT])
160                         cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
161                 if (info->attrs[L2TP_ATTR_UDP_CSUM])
162                         cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
163         }
164
165         if (info->attrs[L2TP_ATTR_DEBUG])
166                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
167
168         tunnel = l2tp_tunnel_find(net, tunnel_id);
169         if (tunnel != NULL) {
170                 ret = -EEXIST;
171                 goto out;
172         }
173
174         ret = -EINVAL;
175         switch (cfg.encap) {
176         case L2TP_ENCAPTYPE_UDP:
177         case L2TP_ENCAPTYPE_IP:
178                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
179                                          peer_tunnel_id, &cfg, &tunnel);
180                 break;
181         }
182
183 out:
184         return ret;
185 }
186
187 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
188 {
189         struct l2tp_tunnel *tunnel;
190         u32 tunnel_id;
191         int ret = 0;
192         struct net *net = genl_info_net(info);
193
194         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
195                 ret = -EINVAL;
196                 goto out;
197         }
198         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
199
200         tunnel = l2tp_tunnel_find(net, tunnel_id);
201         if (tunnel == NULL) {
202                 ret = -ENODEV;
203                 goto out;
204         }
205
206         (void) l2tp_tunnel_delete(tunnel);
207
208 out:
209         return ret;
210 }
211
212 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
213 {
214         struct l2tp_tunnel *tunnel;
215         u32 tunnel_id;
216         int ret = 0;
217         struct net *net = genl_info_net(info);
218
219         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
220                 ret = -EINVAL;
221                 goto out;
222         }
223         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
224
225         tunnel = l2tp_tunnel_find(net, tunnel_id);
226         if (tunnel == NULL) {
227                 ret = -ENODEV;
228                 goto out;
229         }
230
231         if (info->attrs[L2TP_ATTR_DEBUG])
232                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
233
234 out:
235         return ret;
236 }
237
238 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 pid, u32 seq, int flags,
239                                struct l2tp_tunnel *tunnel)
240 {
241         void *hdr;
242         struct nlattr *nest;
243         struct sock *sk = NULL;
244         struct inet_sock *inet;
245 #if IS_ENABLED(CONFIG_IPV6)
246         struct ipv6_pinfo *np = NULL;
247 #endif
248         struct l2tp_stats stats;
249         unsigned int start;
250
251         hdr = genlmsg_put(skb, pid, seq, &l2tp_nl_family, flags,
252                           L2TP_CMD_TUNNEL_GET);
253         if (IS_ERR(hdr))
254                 return PTR_ERR(hdr);
255
256         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
257             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
258             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
259             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
260             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
261                 goto nla_put_failure;
262
263         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
264         if (nest == NULL)
265                 goto nla_put_failure;
266
267         do {
268                 start = u64_stats_fetch_begin(&tunnel->stats.syncp);
269                 stats.tx_packets = tunnel->stats.tx_packets;
270                 stats.tx_bytes = tunnel->stats.tx_bytes;
271                 stats.tx_errors = tunnel->stats.tx_errors;
272                 stats.rx_packets = tunnel->stats.rx_packets;
273                 stats.rx_bytes = tunnel->stats.rx_bytes;
274                 stats.rx_errors = tunnel->stats.rx_errors;
275                 stats.rx_seq_discards = tunnel->stats.rx_seq_discards;
276                 stats.rx_oos_packets = tunnel->stats.rx_oos_packets;
277         } while (u64_stats_fetch_retry(&tunnel->stats.syncp, start));
278
279         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
280             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
281             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
282             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
283             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
284             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
285                         stats.rx_seq_discards) ||
286             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
287                         stats.rx_oos_packets) ||
288             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
289                 goto nla_put_failure;
290         nla_nest_end(skb, nest);
291
292         sk = tunnel->sock;
293         if (!sk)
294                 goto out;
295
296 #if IS_ENABLED(CONFIG_IPV6)
297         if (sk->sk_family == AF_INET6)
298                 np = inet6_sk(sk);
299 #endif
300
301         inet = inet_sk(sk);
302
303         switch (tunnel->encap) {
304         case L2TP_ENCAPTYPE_UDP:
305                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
306                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
307                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM,
308                                (sk->sk_no_check != UDP_CSUM_NOXMIT)))
309                         goto nla_put_failure;
310                 /* NOBREAK */
311         case L2TP_ENCAPTYPE_IP:
312 #if IS_ENABLED(CONFIG_IPV6)
313                 if (np) {
314                         if (nla_put(skb, L2TP_ATTR_IP6_SADDR, sizeof(np->saddr),
315                                     &np->saddr) ||
316                             nla_put(skb, L2TP_ATTR_IP6_DADDR, sizeof(np->daddr),
317                                     &np->daddr))
318                                 goto nla_put_failure;
319                 } else
320 #endif
321                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
322                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
323                         goto nla_put_failure;
324                 break;
325         }
326
327 out:
328         return genlmsg_end(skb, hdr);
329
330 nla_put_failure:
331         genlmsg_cancel(skb, hdr);
332         return -1;
333 }
334
335 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
336 {
337         struct l2tp_tunnel *tunnel;
338         struct sk_buff *msg;
339         u32 tunnel_id;
340         int ret = -ENOBUFS;
341         struct net *net = genl_info_net(info);
342
343         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
344                 ret = -EINVAL;
345                 goto out;
346         }
347
348         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
349
350         tunnel = l2tp_tunnel_find(net, tunnel_id);
351         if (tunnel == NULL) {
352                 ret = -ENODEV;
353                 goto out;
354         }
355
356         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
357         if (!msg) {
358                 ret = -ENOMEM;
359                 goto out;
360         }
361
362         ret = l2tp_nl_tunnel_send(msg, info->snd_pid, info->snd_seq,
363                                   NLM_F_ACK, tunnel);
364         if (ret < 0)
365                 goto err_out;
366
367         return genlmsg_unicast(net, msg, info->snd_pid);
368
369 err_out:
370         nlmsg_free(msg);
371
372 out:
373         return ret;
374 }
375
376 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
377 {
378         int ti = cb->args[0];
379         struct l2tp_tunnel *tunnel;
380         struct net *net = sock_net(skb->sk);
381
382         for (;;) {
383                 tunnel = l2tp_tunnel_find_nth(net, ti);
384                 if (tunnel == NULL)
385                         goto out;
386
387                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).pid,
388                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
389                                         tunnel) <= 0)
390                         goto out;
391
392                 ti++;
393         }
394
395 out:
396         cb->args[0] = ti;
397
398         return skb->len;
399 }
400
401 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
402 {
403         u32 tunnel_id = 0;
404         u32 session_id;
405         u32 peer_session_id;
406         int ret = 0;
407         struct l2tp_tunnel *tunnel;
408         struct l2tp_session *session;
409         struct l2tp_session_cfg cfg = { 0, };
410         struct net *net = genl_info_net(info);
411
412         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
413                 ret = -EINVAL;
414                 goto out;
415         }
416         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
417         tunnel = l2tp_tunnel_find(net, tunnel_id);
418         if (!tunnel) {
419                 ret = -ENODEV;
420                 goto out;
421         }
422
423         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
424                 ret = -EINVAL;
425                 goto out;
426         }
427         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
428         session = l2tp_session_find(net, tunnel, session_id);
429         if (session) {
430                 ret = -EEXIST;
431                 goto out;
432         }
433
434         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
435                 ret = -EINVAL;
436                 goto out;
437         }
438         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
439
440         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
441                 ret = -EINVAL;
442                 goto out;
443         }
444         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
445         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
446                 ret = -EINVAL;
447                 goto out;
448         }
449
450         if (tunnel->version > 2) {
451                 if (info->attrs[L2TP_ATTR_OFFSET])
452                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
453
454                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
455                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
456
457                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
458                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
459                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
460
461                 cfg.l2specific_len = 4;
462                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
463                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
464
465                 if (info->attrs[L2TP_ATTR_COOKIE]) {
466                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
467                         if (len > 8) {
468                                 ret = -EINVAL;
469                                 goto out;
470                         }
471                         cfg.cookie_len = len;
472                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
473                 }
474                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
475                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
476                         if (len > 8) {
477                                 ret = -EINVAL;
478                                 goto out;
479                         }
480                         cfg.peer_cookie_len = len;
481                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
482                 }
483                 if (info->attrs[L2TP_ATTR_IFNAME])
484                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
485
486                 if (info->attrs[L2TP_ATTR_VLAN_ID])
487                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
488         }
489
490         if (info->attrs[L2TP_ATTR_DEBUG])
491                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
492
493         if (info->attrs[L2TP_ATTR_RECV_SEQ])
494                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
495
496         if (info->attrs[L2TP_ATTR_SEND_SEQ])
497                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
498
499         if (info->attrs[L2TP_ATTR_LNS_MODE])
500                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
501
502         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
503                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
504
505         if (info->attrs[L2TP_ATTR_MTU])
506                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
507
508         if (info->attrs[L2TP_ATTR_MRU])
509                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
510
511         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
512             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
513                 ret = -EPROTONOSUPPORT;
514                 goto out;
515         }
516
517         /* Check that pseudowire-specific params are present */
518         switch (cfg.pw_type) {
519         case L2TP_PWTYPE_NONE:
520                 break;
521         case L2TP_PWTYPE_ETH_VLAN:
522                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
523                         ret = -EINVAL;
524                         goto out;
525                 }
526                 break;
527         case L2TP_PWTYPE_ETH:
528                 break;
529         case L2TP_PWTYPE_PPP:
530         case L2TP_PWTYPE_PPP_AC:
531                 break;
532         case L2TP_PWTYPE_IP:
533         default:
534                 ret = -EPROTONOSUPPORT;
535                 break;
536         }
537
538         ret = -EPROTONOSUPPORT;
539         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
540                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
541                         session_id, peer_session_id, &cfg);
542
543 out:
544         return ret;
545 }
546
547 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
548 {
549         int ret = 0;
550         struct l2tp_session *session;
551         u16 pw_type;
552
553         session = l2tp_nl_session_find(info);
554         if (session == NULL) {
555                 ret = -ENODEV;
556                 goto out;
557         }
558
559         pw_type = session->pwtype;
560         if (pw_type < __L2TP_PWTYPE_MAX)
561                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
562                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
563
564 out:
565         return ret;
566 }
567
568 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
569 {
570         int ret = 0;
571         struct l2tp_session *session;
572
573         session = l2tp_nl_session_find(info);
574         if (session == NULL) {
575                 ret = -ENODEV;
576                 goto out;
577         }
578
579         if (info->attrs[L2TP_ATTR_DEBUG])
580                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
581
582         if (info->attrs[L2TP_ATTR_DATA_SEQ])
583                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
584
585         if (info->attrs[L2TP_ATTR_RECV_SEQ])
586                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
587
588         if (info->attrs[L2TP_ATTR_SEND_SEQ])
589                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
590
591         if (info->attrs[L2TP_ATTR_LNS_MODE])
592                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
593
594         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
595                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
596
597         if (info->attrs[L2TP_ATTR_MTU])
598                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
599
600         if (info->attrs[L2TP_ATTR_MRU])
601                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
602
603 out:
604         return ret;
605 }
606
607 static int l2tp_nl_session_send(struct sk_buff *skb, u32 pid, u32 seq, int flags,
608                                 struct l2tp_session *session)
609 {
610         void *hdr;
611         struct nlattr *nest;
612         struct l2tp_tunnel *tunnel = session->tunnel;
613         struct sock *sk = NULL;
614         struct l2tp_stats stats;
615         unsigned int start;
616
617         sk = tunnel->sock;
618
619         hdr = genlmsg_put(skb, pid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
620         if (IS_ERR(hdr))
621                 return PTR_ERR(hdr);
622
623         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
624             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
625             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
626             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
627                         session->peer_session_id) ||
628             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
629             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
630             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
631             (session->mru &&
632              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
633                 goto nla_put_failure;
634
635         if ((session->ifname && session->ifname[0] &&
636              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
637             (session->cookie_len &&
638              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
639                      &session->cookie[0])) ||
640             (session->peer_cookie_len &&
641              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
642                      &session->peer_cookie[0])) ||
643             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
644             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
645             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
646 #ifdef CONFIG_XFRM
647             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
648              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
649 #endif
650             (session->reorder_timeout &&
651              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
652                 goto nla_put_failure;
653
654         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
655         if (nest == NULL)
656                 goto nla_put_failure;
657
658         do {
659                 start = u64_stats_fetch_begin(&session->stats.syncp);
660                 stats.tx_packets = session->stats.tx_packets;
661                 stats.tx_bytes = session->stats.tx_bytes;
662                 stats.tx_errors = session->stats.tx_errors;
663                 stats.rx_packets = session->stats.rx_packets;
664                 stats.rx_bytes = session->stats.rx_bytes;
665                 stats.rx_errors = session->stats.rx_errors;
666                 stats.rx_seq_discards = session->stats.rx_seq_discards;
667                 stats.rx_oos_packets = session->stats.rx_oos_packets;
668         } while (u64_stats_fetch_retry(&session->stats.syncp, start));
669
670         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
671             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
672             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
673             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
674             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
675             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
676                         stats.rx_seq_discards) ||
677             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
678                         stats.rx_oos_packets) ||
679             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
680                 goto nla_put_failure;
681         nla_nest_end(skb, nest);
682
683         return genlmsg_end(skb, hdr);
684
685  nla_put_failure:
686         genlmsg_cancel(skb, hdr);
687         return -1;
688 }
689
690 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
691 {
692         struct l2tp_session *session;
693         struct sk_buff *msg;
694         int ret;
695
696         session = l2tp_nl_session_find(info);
697         if (session == NULL) {
698                 ret = -ENODEV;
699                 goto out;
700         }
701
702         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
703         if (!msg) {
704                 ret = -ENOMEM;
705                 goto out;
706         }
707
708         ret = l2tp_nl_session_send(msg, info->snd_pid, info->snd_seq,
709                                    0, session);
710         if (ret < 0)
711                 goto err_out;
712
713         return genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
714
715 err_out:
716         nlmsg_free(msg);
717
718 out:
719         return ret;
720 }
721
722 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
723 {
724         struct net *net = sock_net(skb->sk);
725         struct l2tp_session *session;
726         struct l2tp_tunnel *tunnel = NULL;
727         int ti = cb->args[0];
728         int si = cb->args[1];
729
730         for (;;) {
731                 if (tunnel == NULL) {
732                         tunnel = l2tp_tunnel_find_nth(net, ti);
733                         if (tunnel == NULL)
734                                 goto out;
735                 }
736
737                 session = l2tp_session_find_nth(tunnel, si);
738                 if (session == NULL) {
739                         ti++;
740                         tunnel = NULL;
741                         si = 0;
742                         continue;
743                 }
744
745                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).pid,
746                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
747                                          session) <= 0)
748                         break;
749
750                 si++;
751         }
752
753 out:
754         cb->args[0] = ti;
755         cb->args[1] = si;
756
757         return skb->len;
758 }
759
760 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
761         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
762         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
763         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
764         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
765         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
766         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
767         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
768         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
769         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
770         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
771         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
772         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
773         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
774         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
775         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
776         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
777         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
778         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
779         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
780         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
781         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
782         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
783         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
784         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
785         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
786         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
787         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
788         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
789         [L2TP_ATTR_IP6_SADDR] = {
790                 .type = NLA_BINARY,
791                 .len = sizeof(struct in6_addr),
792         },
793         [L2TP_ATTR_IP6_DADDR] = {
794                 .type = NLA_BINARY,
795                 .len = sizeof(struct in6_addr),
796         },
797         [L2TP_ATTR_IFNAME] = {
798                 .type = NLA_NUL_STRING,
799                 .len = IFNAMSIZ - 1,
800         },
801         [L2TP_ATTR_COOKIE] = {
802                 .type = NLA_BINARY,
803                 .len = 8,
804         },
805         [L2TP_ATTR_PEER_COOKIE] = {
806                 .type = NLA_BINARY,
807                 .len = 8,
808         },
809 };
810
811 static struct genl_ops l2tp_nl_ops[] = {
812         {
813                 .cmd = L2TP_CMD_NOOP,
814                 .doit = l2tp_nl_cmd_noop,
815                 .policy = l2tp_nl_policy,
816                 /* can be retrieved by unprivileged users */
817         },
818         {
819                 .cmd = L2TP_CMD_TUNNEL_CREATE,
820                 .doit = l2tp_nl_cmd_tunnel_create,
821                 .policy = l2tp_nl_policy,
822                 .flags = GENL_ADMIN_PERM,
823         },
824         {
825                 .cmd = L2TP_CMD_TUNNEL_DELETE,
826                 .doit = l2tp_nl_cmd_tunnel_delete,
827                 .policy = l2tp_nl_policy,
828                 .flags = GENL_ADMIN_PERM,
829         },
830         {
831                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
832                 .doit = l2tp_nl_cmd_tunnel_modify,
833                 .policy = l2tp_nl_policy,
834                 .flags = GENL_ADMIN_PERM,
835         },
836         {
837                 .cmd = L2TP_CMD_TUNNEL_GET,
838                 .doit = l2tp_nl_cmd_tunnel_get,
839                 .dumpit = l2tp_nl_cmd_tunnel_dump,
840                 .policy = l2tp_nl_policy,
841                 .flags = GENL_ADMIN_PERM,
842         },
843         {
844                 .cmd = L2TP_CMD_SESSION_CREATE,
845                 .doit = l2tp_nl_cmd_session_create,
846                 .policy = l2tp_nl_policy,
847                 .flags = GENL_ADMIN_PERM,
848         },
849         {
850                 .cmd = L2TP_CMD_SESSION_DELETE,
851                 .doit = l2tp_nl_cmd_session_delete,
852                 .policy = l2tp_nl_policy,
853                 .flags = GENL_ADMIN_PERM,
854         },
855         {
856                 .cmd = L2TP_CMD_SESSION_MODIFY,
857                 .doit = l2tp_nl_cmd_session_modify,
858                 .policy = l2tp_nl_policy,
859                 .flags = GENL_ADMIN_PERM,
860         },
861         {
862                 .cmd = L2TP_CMD_SESSION_GET,
863                 .doit = l2tp_nl_cmd_session_get,
864                 .dumpit = l2tp_nl_cmd_session_dump,
865                 .policy = l2tp_nl_policy,
866                 .flags = GENL_ADMIN_PERM,
867         },
868 };
869
870 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
871 {
872         int ret;
873
874         ret = -EINVAL;
875         if (pw_type >= __L2TP_PWTYPE_MAX)
876                 goto err;
877
878         genl_lock();
879         ret = -EBUSY;
880         if (l2tp_nl_cmd_ops[pw_type])
881                 goto out;
882
883         l2tp_nl_cmd_ops[pw_type] = ops;
884         ret = 0;
885
886 out:
887         genl_unlock();
888 err:
889         return ret;
890 }
891 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
892
893 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
894 {
895         if (pw_type < __L2TP_PWTYPE_MAX) {
896                 genl_lock();
897                 l2tp_nl_cmd_ops[pw_type] = NULL;
898                 genl_unlock();
899         }
900 }
901 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
902
903 static int l2tp_nl_init(void)
904 {
905         int err;
906
907         pr_info("L2TP netlink interface\n");
908         err = genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops,
909                                             ARRAY_SIZE(l2tp_nl_ops));
910
911         return err;
912 }
913
914 static void l2tp_nl_cleanup(void)
915 {
916         genl_unregister_family(&l2tp_nl_family);
917 }
918
919 module_init(l2tp_nl_init);
920 module_exit(l2tp_nl_cleanup);
921
922 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
923 MODULE_DESCRIPTION("L2TP netlink");
924 MODULE_LICENSE("GPL");
925 MODULE_VERSION("1.0");
926 MODULE_ALIAS_GENL_FAMILY("l2tp");