l2tp: set netnsok flag for netlink messages
[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         .netnsok        = true,
41 };
42
43 /* Accessed under genl lock */
44 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
45
46 static struct l2tp_session *l2tp_nl_session_find(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(info->attrs[L2TP_ATTR_IFNAME]);
57                 session = l2tp_session_find_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(info->attrs[L2TP_ATTR_CONN_ID]);
61                 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
62                 tunnel = l2tp_tunnel_find(net, tunnel_id);
63                 if (tunnel)
64                         session = l2tp_session_find(net, tunnel, session_id);
65         }
66
67         return session;
68 }
69
70 static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
71 {
72         struct sk_buff *msg;
73         void *hdr;
74         int ret = -ENOBUFS;
75
76         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
77         if (!msg) {
78                 ret = -ENOMEM;
79                 goto out;
80         }
81
82         hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
83                           &l2tp_nl_family, 0, L2TP_CMD_NOOP);
84         if (!hdr) {
85                 ret = -EMSGSIZE;
86                 goto err_out;
87         }
88
89         genlmsg_end(msg, hdr);
90
91         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
92
93 err_out:
94         nlmsg_free(msg);
95
96 out:
97         return ret;
98 }
99
100 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
101 {
102         u32 tunnel_id;
103         u32 peer_tunnel_id;
104         int proto_version;
105         int fd;
106         int ret = 0;
107         struct l2tp_tunnel_cfg cfg = { 0, };
108         struct l2tp_tunnel *tunnel;
109         struct net *net = genl_info_net(info);
110
111         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
112                 ret = -EINVAL;
113                 goto out;
114         }
115         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
116
117         if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
118                 ret = -EINVAL;
119                 goto out;
120         }
121         peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
122
123         if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
124                 ret = -EINVAL;
125                 goto out;
126         }
127         proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
128
129         if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
130                 ret = -EINVAL;
131                 goto out;
132         }
133         cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
134
135         fd = -1;
136         if (info->attrs[L2TP_ATTR_FD]) {
137                 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
138         } else {
139 #if IS_ENABLED(CONFIG_IPV6)
140                 if (info->attrs[L2TP_ATTR_IP6_SADDR] &&
141                     info->attrs[L2TP_ATTR_IP6_DADDR]) {
142                         cfg.local_ip6 = nla_data(
143                                 info->attrs[L2TP_ATTR_IP6_SADDR]);
144                         cfg.peer_ip6 = nla_data(
145                                 info->attrs[L2TP_ATTR_IP6_DADDR]);
146                 } else
147 #endif
148                 if (info->attrs[L2TP_ATTR_IP_SADDR] &&
149                     info->attrs[L2TP_ATTR_IP_DADDR]) {
150                         cfg.local_ip.s_addr = nla_get_be32(
151                                 info->attrs[L2TP_ATTR_IP_SADDR]);
152                         cfg.peer_ip.s_addr = nla_get_be32(
153                                 info->attrs[L2TP_ATTR_IP_DADDR]);
154                 } else {
155                         ret = -EINVAL;
156                         goto out;
157                 }
158                 if (info->attrs[L2TP_ATTR_UDP_SPORT])
159                         cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
160                 if (info->attrs[L2TP_ATTR_UDP_DPORT])
161                         cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
162                 if (info->attrs[L2TP_ATTR_UDP_CSUM])
163                         cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
164         }
165
166         if (info->attrs[L2TP_ATTR_DEBUG])
167                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
168
169         tunnel = l2tp_tunnel_find(net, tunnel_id);
170         if (tunnel != NULL) {
171                 ret = -EEXIST;
172                 goto out;
173         }
174
175         ret = -EINVAL;
176         switch (cfg.encap) {
177         case L2TP_ENCAPTYPE_UDP:
178         case L2TP_ENCAPTYPE_IP:
179                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
180                                          peer_tunnel_id, &cfg, &tunnel);
181                 break;
182         }
183
184 out:
185         return ret;
186 }
187
188 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
189 {
190         struct l2tp_tunnel *tunnel;
191         u32 tunnel_id;
192         int ret = 0;
193         struct net *net = genl_info_net(info);
194
195         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
196                 ret = -EINVAL;
197                 goto out;
198         }
199         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
200
201         tunnel = l2tp_tunnel_find(net, tunnel_id);
202         if (tunnel == NULL) {
203                 ret = -ENODEV;
204                 goto out;
205         }
206
207         (void) l2tp_tunnel_delete(tunnel);
208
209 out:
210         return ret;
211 }
212
213 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
214 {
215         struct l2tp_tunnel *tunnel;
216         u32 tunnel_id;
217         int ret = 0;
218         struct net *net = genl_info_net(info);
219
220         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
221                 ret = -EINVAL;
222                 goto out;
223         }
224         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
225
226         tunnel = l2tp_tunnel_find(net, tunnel_id);
227         if (tunnel == NULL) {
228                 ret = -ENODEV;
229                 goto out;
230         }
231
232         if (info->attrs[L2TP_ATTR_DEBUG])
233                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
234
235 out:
236         return ret;
237 }
238
239 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
240                                struct l2tp_tunnel *tunnel)
241 {
242         void *hdr;
243         struct nlattr *nest;
244         struct sock *sk = NULL;
245         struct inet_sock *inet;
246 #if IS_ENABLED(CONFIG_IPV6)
247         struct ipv6_pinfo *np = NULL;
248 #endif
249         struct l2tp_stats stats;
250         unsigned int start;
251
252         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags,
253                           L2TP_CMD_TUNNEL_GET);
254         if (!hdr)
255                 return -EMSGSIZE;
256
257         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
258             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
259             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
260             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
261             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
262                 goto nla_put_failure;
263
264         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
265         if (nest == NULL)
266                 goto nla_put_failure;
267
268         do {
269                 start = u64_stats_fetch_begin(&tunnel->stats.syncp);
270                 stats.tx_packets = tunnel->stats.tx_packets;
271                 stats.tx_bytes = tunnel->stats.tx_bytes;
272                 stats.tx_errors = tunnel->stats.tx_errors;
273                 stats.rx_packets = tunnel->stats.rx_packets;
274                 stats.rx_bytes = tunnel->stats.rx_bytes;
275                 stats.rx_errors = tunnel->stats.rx_errors;
276                 stats.rx_seq_discards = tunnel->stats.rx_seq_discards;
277                 stats.rx_oos_packets = tunnel->stats.rx_oos_packets;
278         } while (u64_stats_fetch_retry(&tunnel->stats.syncp, start));
279
280         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
281             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
282             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
283             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
284             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
285             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
286                         stats.rx_seq_discards) ||
287             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
288                         stats.rx_oos_packets) ||
289             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
290                 goto nla_put_failure;
291         nla_nest_end(skb, nest);
292
293         sk = tunnel->sock;
294         if (!sk)
295                 goto out;
296
297 #if IS_ENABLED(CONFIG_IPV6)
298         if (sk->sk_family == AF_INET6)
299                 np = inet6_sk(sk);
300 #endif
301
302         inet = inet_sk(sk);
303
304         switch (tunnel->encap) {
305         case L2TP_ENCAPTYPE_UDP:
306                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
307                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
308                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM,
309                                (sk->sk_no_check != UDP_CSUM_NOXMIT)))
310                         goto nla_put_failure;
311                 /* NOBREAK */
312         case L2TP_ENCAPTYPE_IP:
313 #if IS_ENABLED(CONFIG_IPV6)
314                 if (np) {
315                         if (nla_put(skb, L2TP_ATTR_IP6_SADDR, sizeof(np->saddr),
316                                     &np->saddr) ||
317                             nla_put(skb, L2TP_ATTR_IP6_DADDR, sizeof(np->daddr),
318                                     &np->daddr))
319                                 goto nla_put_failure;
320                 } else
321 #endif
322                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
323                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
324                         goto nla_put_failure;
325                 break;
326         }
327
328 out:
329         return genlmsg_end(skb, hdr);
330
331 nla_put_failure:
332         genlmsg_cancel(skb, hdr);
333         return -1;
334 }
335
336 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
337 {
338         struct l2tp_tunnel *tunnel;
339         struct sk_buff *msg;
340         u32 tunnel_id;
341         int ret = -ENOBUFS;
342         struct net *net = genl_info_net(info);
343
344         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
345                 ret = -EINVAL;
346                 goto out;
347         }
348
349         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
350
351         tunnel = l2tp_tunnel_find(net, tunnel_id);
352         if (tunnel == NULL) {
353                 ret = -ENODEV;
354                 goto out;
355         }
356
357         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
358         if (!msg) {
359                 ret = -ENOMEM;
360                 goto out;
361         }
362
363         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
364                                   NLM_F_ACK, tunnel);
365         if (ret < 0)
366                 goto err_out;
367
368         return genlmsg_unicast(net, msg, info->snd_portid);
369
370 err_out:
371         nlmsg_free(msg);
372
373 out:
374         return ret;
375 }
376
377 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
378 {
379         int ti = cb->args[0];
380         struct l2tp_tunnel *tunnel;
381         struct net *net = sock_net(skb->sk);
382
383         for (;;) {
384                 tunnel = l2tp_tunnel_find_nth(net, ti);
385                 if (tunnel == NULL)
386                         goto out;
387
388                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
389                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
390                                         tunnel) <= 0)
391                         goto out;
392
393                 ti++;
394         }
395
396 out:
397         cb->args[0] = ti;
398
399         return skb->len;
400 }
401
402 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
403 {
404         u32 tunnel_id = 0;
405         u32 session_id;
406         u32 peer_session_id;
407         int ret = 0;
408         struct l2tp_tunnel *tunnel;
409         struct l2tp_session *session;
410         struct l2tp_session_cfg cfg = { 0, };
411         struct net *net = genl_info_net(info);
412
413         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
414                 ret = -EINVAL;
415                 goto out;
416         }
417         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
418         tunnel = l2tp_tunnel_find(net, tunnel_id);
419         if (!tunnel) {
420                 ret = -ENODEV;
421                 goto out;
422         }
423
424         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
425                 ret = -EINVAL;
426                 goto out;
427         }
428         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
429         session = l2tp_session_find(net, tunnel, session_id);
430         if (session) {
431                 ret = -EEXIST;
432                 goto out;
433         }
434
435         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
436                 ret = -EINVAL;
437                 goto out;
438         }
439         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
440
441         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
442                 ret = -EINVAL;
443                 goto out;
444         }
445         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
446         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
447                 ret = -EINVAL;
448                 goto out;
449         }
450
451         if (tunnel->version > 2) {
452                 if (info->attrs[L2TP_ATTR_OFFSET])
453                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
454
455                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
456                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
457
458                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
459                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
460                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
461
462                 cfg.l2specific_len = 4;
463                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
464                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
465
466                 if (info->attrs[L2TP_ATTR_COOKIE]) {
467                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
468                         if (len > 8) {
469                                 ret = -EINVAL;
470                                 goto out;
471                         }
472                         cfg.cookie_len = len;
473                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
474                 }
475                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
476                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
477                         if (len > 8) {
478                                 ret = -EINVAL;
479                                 goto out;
480                         }
481                         cfg.peer_cookie_len = len;
482                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
483                 }
484                 if (info->attrs[L2TP_ATTR_IFNAME])
485                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
486
487                 if (info->attrs[L2TP_ATTR_VLAN_ID])
488                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
489         }
490
491         if (info->attrs[L2TP_ATTR_DEBUG])
492                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
493
494         if (info->attrs[L2TP_ATTR_RECV_SEQ])
495                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
496
497         if (info->attrs[L2TP_ATTR_SEND_SEQ])
498                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
499
500         if (info->attrs[L2TP_ATTR_LNS_MODE])
501                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
502
503         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
504                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
505
506         if (info->attrs[L2TP_ATTR_MTU])
507                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
508
509         if (info->attrs[L2TP_ATTR_MRU])
510                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
511
512         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
513             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
514                 ret = -EPROTONOSUPPORT;
515                 goto out;
516         }
517
518         /* Check that pseudowire-specific params are present */
519         switch (cfg.pw_type) {
520         case L2TP_PWTYPE_NONE:
521                 break;
522         case L2TP_PWTYPE_ETH_VLAN:
523                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
524                         ret = -EINVAL;
525                         goto out;
526                 }
527                 break;
528         case L2TP_PWTYPE_ETH:
529                 break;
530         case L2TP_PWTYPE_PPP:
531         case L2TP_PWTYPE_PPP_AC:
532                 break;
533         case L2TP_PWTYPE_IP:
534         default:
535                 ret = -EPROTONOSUPPORT;
536                 break;
537         }
538
539         ret = -EPROTONOSUPPORT;
540         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
541                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
542                         session_id, peer_session_id, &cfg);
543
544 out:
545         return ret;
546 }
547
548 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
549 {
550         int ret = 0;
551         struct l2tp_session *session;
552         u16 pw_type;
553
554         session = l2tp_nl_session_find(info);
555         if (session == NULL) {
556                 ret = -ENODEV;
557                 goto out;
558         }
559
560         pw_type = session->pwtype;
561         if (pw_type < __L2TP_PWTYPE_MAX)
562                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
563                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
564
565 out:
566         return ret;
567 }
568
569 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
570 {
571         int ret = 0;
572         struct l2tp_session *session;
573
574         session = l2tp_nl_session_find(info);
575         if (session == NULL) {
576                 ret = -ENODEV;
577                 goto out;
578         }
579
580         if (info->attrs[L2TP_ATTR_DEBUG])
581                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
582
583         if (info->attrs[L2TP_ATTR_DATA_SEQ])
584                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
585
586         if (info->attrs[L2TP_ATTR_RECV_SEQ])
587                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
588
589         if (info->attrs[L2TP_ATTR_SEND_SEQ])
590                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
591
592         if (info->attrs[L2TP_ATTR_LNS_MODE])
593                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
594
595         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
596                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
597
598         if (info->attrs[L2TP_ATTR_MTU])
599                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
600
601         if (info->attrs[L2TP_ATTR_MRU])
602                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
603
604 out:
605         return ret;
606 }
607
608 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
609                                 struct l2tp_session *session)
610 {
611         void *hdr;
612         struct nlattr *nest;
613         struct l2tp_tunnel *tunnel = session->tunnel;
614         struct sock *sk = NULL;
615         struct l2tp_stats stats;
616         unsigned int start;
617
618         sk = tunnel->sock;
619
620         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
621         if (!hdr)
622                 return -EMSGSIZE;
623
624         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
625             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
626             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
627             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
628                         session->peer_session_id) ||
629             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
630             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
631             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
632             (session->mru &&
633              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
634                 goto nla_put_failure;
635
636         if ((session->ifname[0] &&
637              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
638             (session->cookie_len &&
639              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
640                      &session->cookie[0])) ||
641             (session->peer_cookie_len &&
642              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
643                      &session->peer_cookie[0])) ||
644             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
645             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
646             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
647 #ifdef CONFIG_XFRM
648             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
649              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
650 #endif
651             (session->reorder_timeout &&
652              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
653                 goto nla_put_failure;
654
655         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
656         if (nest == NULL)
657                 goto nla_put_failure;
658
659         do {
660                 start = u64_stats_fetch_begin(&session->stats.syncp);
661                 stats.tx_packets = session->stats.tx_packets;
662                 stats.tx_bytes = session->stats.tx_bytes;
663                 stats.tx_errors = session->stats.tx_errors;
664                 stats.rx_packets = session->stats.rx_packets;
665                 stats.rx_bytes = session->stats.rx_bytes;
666                 stats.rx_errors = session->stats.rx_errors;
667                 stats.rx_seq_discards = session->stats.rx_seq_discards;
668                 stats.rx_oos_packets = session->stats.rx_oos_packets;
669         } while (u64_stats_fetch_retry(&session->stats.syncp, start));
670
671         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
672             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
673             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
674             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
675             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
676             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
677                         stats.rx_seq_discards) ||
678             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
679                         stats.rx_oos_packets) ||
680             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
681                 goto nla_put_failure;
682         nla_nest_end(skb, nest);
683
684         return genlmsg_end(skb, hdr);
685
686  nla_put_failure:
687         genlmsg_cancel(skb, hdr);
688         return -1;
689 }
690
691 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
692 {
693         struct l2tp_session *session;
694         struct sk_buff *msg;
695         int ret;
696
697         session = l2tp_nl_session_find(info);
698         if (session == NULL) {
699                 ret = -ENODEV;
700                 goto out;
701         }
702
703         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
704         if (!msg) {
705                 ret = -ENOMEM;
706                 goto out;
707         }
708
709         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
710                                    0, session);
711         if (ret < 0)
712                 goto err_out;
713
714         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
715
716 err_out:
717         nlmsg_free(msg);
718
719 out:
720         return ret;
721 }
722
723 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
724 {
725         struct net *net = sock_net(skb->sk);
726         struct l2tp_session *session;
727         struct l2tp_tunnel *tunnel = NULL;
728         int ti = cb->args[0];
729         int si = cb->args[1];
730
731         for (;;) {
732                 if (tunnel == NULL) {
733                         tunnel = l2tp_tunnel_find_nth(net, ti);
734                         if (tunnel == NULL)
735                                 goto out;
736                 }
737
738                 session = l2tp_session_find_nth(tunnel, si);
739                 if (session == NULL) {
740                         ti++;
741                         tunnel = NULL;
742                         si = 0;
743                         continue;
744                 }
745
746                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
747                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
748                                          session) <= 0)
749                         break;
750
751                 si++;
752         }
753
754 out:
755         cb->args[0] = ti;
756         cb->args[1] = si;
757
758         return skb->len;
759 }
760
761 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
762         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
763         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
764         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
765         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
766         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
767         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
768         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
769         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
770         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
771         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
772         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
773         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
774         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
775         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
776         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
777         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
778         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
779         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
780         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
781         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
782         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
783         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
784         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
785         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
786         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
787         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
788         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
789         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
790         [L2TP_ATTR_IP6_SADDR] = {
791                 .type = NLA_BINARY,
792                 .len = sizeof(struct in6_addr),
793         },
794         [L2TP_ATTR_IP6_DADDR] = {
795                 .type = NLA_BINARY,
796                 .len = sizeof(struct in6_addr),
797         },
798         [L2TP_ATTR_IFNAME] = {
799                 .type = NLA_NUL_STRING,
800                 .len = IFNAMSIZ - 1,
801         },
802         [L2TP_ATTR_COOKIE] = {
803                 .type = NLA_BINARY,
804                 .len = 8,
805         },
806         [L2TP_ATTR_PEER_COOKIE] = {
807                 .type = NLA_BINARY,
808                 .len = 8,
809         },
810 };
811
812 static struct genl_ops l2tp_nl_ops[] = {
813         {
814                 .cmd = L2TP_CMD_NOOP,
815                 .doit = l2tp_nl_cmd_noop,
816                 .policy = l2tp_nl_policy,
817                 /* can be retrieved by unprivileged users */
818         },
819         {
820                 .cmd = L2TP_CMD_TUNNEL_CREATE,
821                 .doit = l2tp_nl_cmd_tunnel_create,
822                 .policy = l2tp_nl_policy,
823                 .flags = GENL_ADMIN_PERM,
824         },
825         {
826                 .cmd = L2TP_CMD_TUNNEL_DELETE,
827                 .doit = l2tp_nl_cmd_tunnel_delete,
828                 .policy = l2tp_nl_policy,
829                 .flags = GENL_ADMIN_PERM,
830         },
831         {
832                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
833                 .doit = l2tp_nl_cmd_tunnel_modify,
834                 .policy = l2tp_nl_policy,
835                 .flags = GENL_ADMIN_PERM,
836         },
837         {
838                 .cmd = L2TP_CMD_TUNNEL_GET,
839                 .doit = l2tp_nl_cmd_tunnel_get,
840                 .dumpit = l2tp_nl_cmd_tunnel_dump,
841                 .policy = l2tp_nl_policy,
842                 .flags = GENL_ADMIN_PERM,
843         },
844         {
845                 .cmd = L2TP_CMD_SESSION_CREATE,
846                 .doit = l2tp_nl_cmd_session_create,
847                 .policy = l2tp_nl_policy,
848                 .flags = GENL_ADMIN_PERM,
849         },
850         {
851                 .cmd = L2TP_CMD_SESSION_DELETE,
852                 .doit = l2tp_nl_cmd_session_delete,
853                 .policy = l2tp_nl_policy,
854                 .flags = GENL_ADMIN_PERM,
855         },
856         {
857                 .cmd = L2TP_CMD_SESSION_MODIFY,
858                 .doit = l2tp_nl_cmd_session_modify,
859                 .policy = l2tp_nl_policy,
860                 .flags = GENL_ADMIN_PERM,
861         },
862         {
863                 .cmd = L2TP_CMD_SESSION_GET,
864                 .doit = l2tp_nl_cmd_session_get,
865                 .dumpit = l2tp_nl_cmd_session_dump,
866                 .policy = l2tp_nl_policy,
867                 .flags = GENL_ADMIN_PERM,
868         },
869 };
870
871 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
872 {
873         int ret;
874
875         ret = -EINVAL;
876         if (pw_type >= __L2TP_PWTYPE_MAX)
877                 goto err;
878
879         genl_lock();
880         ret = -EBUSY;
881         if (l2tp_nl_cmd_ops[pw_type])
882                 goto out;
883
884         l2tp_nl_cmd_ops[pw_type] = ops;
885         ret = 0;
886
887 out:
888         genl_unlock();
889 err:
890         return ret;
891 }
892 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
893
894 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
895 {
896         if (pw_type < __L2TP_PWTYPE_MAX) {
897                 genl_lock();
898                 l2tp_nl_cmd_ops[pw_type] = NULL;
899                 genl_unlock();
900         }
901 }
902 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
903
904 static int l2tp_nl_init(void)
905 {
906         int err;
907
908         pr_info("L2TP netlink interface\n");
909         err = genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops,
910                                             ARRAY_SIZE(l2tp_nl_ops));
911
912         return err;
913 }
914
915 static void l2tp_nl_cleanup(void)
916 {
917         genl_unregister_family(&l2tp_nl_family);
918 }
919
920 module_init(l2tp_nl_init);
921 module_exit(l2tp_nl_cleanup);
922
923 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
924 MODULE_DESCRIPTION("L2TP netlink");
925 MODULE_LICENSE("GPL");
926 MODULE_VERSION("1.0");
927 MODULE_ALIAS_GENL_FAMILY("l2tp");