Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[firefly-linux-kernel-4.4.55.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 #if IS_ENABLED(CONFIG_IPV6)
166                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX])
167                         cfg.udp6_zero_tx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
168                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX])
169                         cfg.udp6_zero_rx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
170 #endif
171         }
172
173         if (info->attrs[L2TP_ATTR_DEBUG])
174                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
175
176         tunnel = l2tp_tunnel_find(net, tunnel_id);
177         if (tunnel != NULL) {
178                 ret = -EEXIST;
179                 goto out;
180         }
181
182         ret = -EINVAL;
183         switch (cfg.encap) {
184         case L2TP_ENCAPTYPE_UDP:
185         case L2TP_ENCAPTYPE_IP:
186                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
187                                          peer_tunnel_id, &cfg, &tunnel);
188                 break;
189         }
190
191 out:
192         return ret;
193 }
194
195 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
196 {
197         struct l2tp_tunnel *tunnel;
198         u32 tunnel_id;
199         int ret = 0;
200         struct net *net = genl_info_net(info);
201
202         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
203                 ret = -EINVAL;
204                 goto out;
205         }
206         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
207
208         tunnel = l2tp_tunnel_find(net, tunnel_id);
209         if (tunnel == NULL) {
210                 ret = -ENODEV;
211                 goto out;
212         }
213
214         (void) l2tp_tunnel_delete(tunnel);
215
216 out:
217         return ret;
218 }
219
220 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
221 {
222         struct l2tp_tunnel *tunnel;
223         u32 tunnel_id;
224         int ret = 0;
225         struct net *net = genl_info_net(info);
226
227         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
228                 ret = -EINVAL;
229                 goto out;
230         }
231         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
232
233         tunnel = l2tp_tunnel_find(net, tunnel_id);
234         if (tunnel == NULL) {
235                 ret = -ENODEV;
236                 goto out;
237         }
238
239         if (info->attrs[L2TP_ATTR_DEBUG])
240                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
241
242 out:
243         return ret;
244 }
245
246 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
247                                struct l2tp_tunnel *tunnel)
248 {
249         void *hdr;
250         struct nlattr *nest;
251         struct sock *sk = NULL;
252         struct inet_sock *inet;
253 #if IS_ENABLED(CONFIG_IPV6)
254         struct ipv6_pinfo *np = NULL;
255 #endif
256
257         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags,
258                           L2TP_CMD_TUNNEL_GET);
259         if (!hdr)
260                 return -EMSGSIZE;
261
262         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
263             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
264             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
265             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
266             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
267                 goto nla_put_failure;
268
269         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
270         if (nest == NULL)
271                 goto nla_put_failure;
272
273         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
274                     atomic_long_read(&tunnel->stats.tx_packets)) ||
275             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
276                     atomic_long_read(&tunnel->stats.tx_bytes)) ||
277             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
278                     atomic_long_read(&tunnel->stats.tx_errors)) ||
279             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
280                     atomic_long_read(&tunnel->stats.rx_packets)) ||
281             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
282                     atomic_long_read(&tunnel->stats.rx_bytes)) ||
283             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
284                     atomic_long_read(&tunnel->stats.rx_seq_discards)) ||
285             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
286                     atomic_long_read(&tunnel->stats.rx_oos_packets)) ||
287             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
288                     atomic_long_read(&tunnel->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, !sk->sk_no_check_tx))
308                         goto nla_put_failure;
309                 /* NOBREAK */
310         case L2TP_ENCAPTYPE_IP:
311 #if IS_ENABLED(CONFIG_IPV6)
312                 if (np) {
313                         if (nla_put(skb, L2TP_ATTR_IP6_SADDR, sizeof(np->saddr),
314                                     &np->saddr) ||
315                             nla_put(skb, L2TP_ATTR_IP6_DADDR, sizeof(sk->sk_v6_daddr),
316                                     &sk->sk_v6_daddr))
317                                 goto nla_put_failure;
318                 } else
319 #endif
320                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
321                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
322                         goto nla_put_failure;
323                 break;
324         }
325
326 out:
327         return genlmsg_end(skb, hdr);
328
329 nla_put_failure:
330         genlmsg_cancel(skb, hdr);
331         return -1;
332 }
333
334 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
335 {
336         struct l2tp_tunnel *tunnel;
337         struct sk_buff *msg;
338         u32 tunnel_id;
339         int ret = -ENOBUFS;
340         struct net *net = genl_info_net(info);
341
342         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
343                 ret = -EINVAL;
344                 goto out;
345         }
346
347         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
348
349         tunnel = l2tp_tunnel_find(net, tunnel_id);
350         if (tunnel == NULL) {
351                 ret = -ENODEV;
352                 goto out;
353         }
354
355         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
356         if (!msg) {
357                 ret = -ENOMEM;
358                 goto out;
359         }
360
361         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
362                                   NLM_F_ACK, tunnel);
363         if (ret < 0)
364                 goto err_out;
365
366         return genlmsg_unicast(net, msg, info->snd_portid);
367
368 err_out:
369         nlmsg_free(msg);
370
371 out:
372         return ret;
373 }
374
375 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
376 {
377         int ti = cb->args[0];
378         struct l2tp_tunnel *tunnel;
379         struct net *net = sock_net(skb->sk);
380
381         for (;;) {
382                 tunnel = l2tp_tunnel_find_nth(net, ti);
383                 if (tunnel == NULL)
384                         goto out;
385
386                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
387                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
388                                         tunnel) <= 0)
389                         goto out;
390
391                 ti++;
392         }
393
394 out:
395         cb->args[0] = ti;
396
397         return skb->len;
398 }
399
400 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
401 {
402         u32 tunnel_id = 0;
403         u32 session_id;
404         u32 peer_session_id;
405         int ret = 0;
406         struct l2tp_tunnel *tunnel;
407         struct l2tp_session *session;
408         struct l2tp_session_cfg cfg = { 0, };
409         struct net *net = genl_info_net(info);
410
411         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
412                 ret = -EINVAL;
413                 goto out;
414         }
415         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
416         tunnel = l2tp_tunnel_find(net, tunnel_id);
417         if (!tunnel) {
418                 ret = -ENODEV;
419                 goto out;
420         }
421
422         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
423                 ret = -EINVAL;
424                 goto out;
425         }
426         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
427         session = l2tp_session_find(net, tunnel, session_id);
428         if (session) {
429                 ret = -EEXIST;
430                 goto out;
431         }
432
433         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
434                 ret = -EINVAL;
435                 goto out;
436         }
437         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
438
439         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
440                 ret = -EINVAL;
441                 goto out;
442         }
443         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
444         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
445                 ret = -EINVAL;
446                 goto out;
447         }
448
449         if (tunnel->version > 2) {
450                 if (info->attrs[L2TP_ATTR_OFFSET])
451                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
452
453                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
454                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
455
456                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
457                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
458                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
459
460                 cfg.l2specific_len = 4;
461                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
462                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
463
464                 if (info->attrs[L2TP_ATTR_COOKIE]) {
465                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
466                         if (len > 8) {
467                                 ret = -EINVAL;
468                                 goto out;
469                         }
470                         cfg.cookie_len = len;
471                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
472                 }
473                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
474                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
475                         if (len > 8) {
476                                 ret = -EINVAL;
477                                 goto out;
478                         }
479                         cfg.peer_cookie_len = len;
480                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
481                 }
482                 if (info->attrs[L2TP_ATTR_IFNAME])
483                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
484
485                 if (info->attrs[L2TP_ATTR_VLAN_ID])
486                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
487         }
488
489         if (info->attrs[L2TP_ATTR_DEBUG])
490                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
491
492         if (info->attrs[L2TP_ATTR_RECV_SEQ])
493                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
494
495         if (info->attrs[L2TP_ATTR_SEND_SEQ])
496                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
497
498         if (info->attrs[L2TP_ATTR_LNS_MODE])
499                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
500
501         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
502                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
503
504         if (info->attrs[L2TP_ATTR_MTU])
505                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
506
507         if (info->attrs[L2TP_ATTR_MRU])
508                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
509
510         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
511             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
512                 ret = -EPROTONOSUPPORT;
513                 goto out;
514         }
515
516         /* Check that pseudowire-specific params are present */
517         switch (cfg.pw_type) {
518         case L2TP_PWTYPE_NONE:
519                 break;
520         case L2TP_PWTYPE_ETH_VLAN:
521                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
522                         ret = -EINVAL;
523                         goto out;
524                 }
525                 break;
526         case L2TP_PWTYPE_ETH:
527                 break;
528         case L2TP_PWTYPE_PPP:
529         case L2TP_PWTYPE_PPP_AC:
530                 break;
531         case L2TP_PWTYPE_IP:
532         default:
533                 ret = -EPROTONOSUPPORT;
534                 break;
535         }
536
537         ret = -EPROTONOSUPPORT;
538         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
539                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
540                         session_id, peer_session_id, &cfg);
541
542 out:
543         return ret;
544 }
545
546 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
547 {
548         int ret = 0;
549         struct l2tp_session *session;
550         u16 pw_type;
551
552         session = l2tp_nl_session_find(info);
553         if (session == NULL) {
554                 ret = -ENODEV;
555                 goto out;
556         }
557
558         pw_type = session->pwtype;
559         if (pw_type < __L2TP_PWTYPE_MAX)
560                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
561                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
562
563 out:
564         return ret;
565 }
566
567 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
568 {
569         int ret = 0;
570         struct l2tp_session *session;
571
572         session = l2tp_nl_session_find(info);
573         if (session == NULL) {
574                 ret = -ENODEV;
575                 goto out;
576         }
577
578         if (info->attrs[L2TP_ATTR_DEBUG])
579                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
580
581         if (info->attrs[L2TP_ATTR_DATA_SEQ])
582                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
583
584         if (info->attrs[L2TP_ATTR_RECV_SEQ])
585                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
586
587         if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
588                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
589                 l2tp_session_set_header_len(session, session->tunnel->version);
590         }
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
616         sk = tunnel->sock;
617
618         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
619         if (!hdr)
620                 return -EMSGSIZE;
621
622         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
623             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
624             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
625             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
626                         session->peer_session_id) ||
627             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
628             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
629             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
630             (session->mru &&
631              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
632                 goto nla_put_failure;
633
634         if ((session->ifname[0] &&
635              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
636             (session->cookie_len &&
637              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
638                      &session->cookie[0])) ||
639             (session->peer_cookie_len &&
640              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
641                      &session->peer_cookie[0])) ||
642             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
643             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
644             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
645 #ifdef CONFIG_XFRM
646             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
647              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
648 #endif
649             (session->reorder_timeout &&
650              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
651                 goto nla_put_failure;
652
653         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
654         if (nest == NULL)
655                 goto nla_put_failure;
656
657         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
658                 atomic_long_read(&session->stats.tx_packets)) ||
659             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
660                 atomic_long_read(&session->stats.tx_bytes)) ||
661             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
662                 atomic_long_read(&session->stats.tx_errors)) ||
663             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
664                 atomic_long_read(&session->stats.rx_packets)) ||
665             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
666                 atomic_long_read(&session->stats.rx_bytes)) ||
667             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
668                 atomic_long_read(&session->stats.rx_seq_discards)) ||
669             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
670                 atomic_long_read(&session->stats.rx_oos_packets)) ||
671             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
672                 atomic_long_read(&session->stats.rx_errors)))
673                 goto nla_put_failure;
674         nla_nest_end(skb, nest);
675
676         return genlmsg_end(skb, hdr);
677
678  nla_put_failure:
679         genlmsg_cancel(skb, hdr);
680         return -1;
681 }
682
683 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
684 {
685         struct l2tp_session *session;
686         struct sk_buff *msg;
687         int ret;
688
689         session = l2tp_nl_session_find(info);
690         if (session == NULL) {
691                 ret = -ENODEV;
692                 goto out;
693         }
694
695         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
696         if (!msg) {
697                 ret = -ENOMEM;
698                 goto out;
699         }
700
701         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
702                                    0, session);
703         if (ret < 0)
704                 goto err_out;
705
706         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
707
708 err_out:
709         nlmsg_free(msg);
710
711 out:
712         return ret;
713 }
714
715 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
716 {
717         struct net *net = sock_net(skb->sk);
718         struct l2tp_session *session;
719         struct l2tp_tunnel *tunnel = NULL;
720         int ti = cb->args[0];
721         int si = cb->args[1];
722
723         for (;;) {
724                 if (tunnel == NULL) {
725                         tunnel = l2tp_tunnel_find_nth(net, ti);
726                         if (tunnel == NULL)
727                                 goto out;
728                 }
729
730                 session = l2tp_session_find_nth(tunnel, si);
731                 if (session == NULL) {
732                         ti++;
733                         tunnel = NULL;
734                         si = 0;
735                         continue;
736                 }
737
738                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
739                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
740                                          session) <= 0)
741                         break;
742
743                 si++;
744         }
745
746 out:
747         cb->args[0] = ti;
748         cb->args[1] = si;
749
750         return skb->len;
751 }
752
753 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
754         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
755         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
756         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
757         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
758         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
759         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
760         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
761         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
762         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
763         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
764         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
765         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
766         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
767         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
768         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
769         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
770         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
771         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
772         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
773         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
774         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
775         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
776         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
777         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
778         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
779         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
780         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
781         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
782         [L2TP_ATTR_IP6_SADDR] = {
783                 .type = NLA_BINARY,
784                 .len = sizeof(struct in6_addr),
785         },
786         [L2TP_ATTR_IP6_DADDR] = {
787                 .type = NLA_BINARY,
788                 .len = sizeof(struct in6_addr),
789         },
790         [L2TP_ATTR_IFNAME] = {
791                 .type = NLA_NUL_STRING,
792                 .len = IFNAMSIZ - 1,
793         },
794         [L2TP_ATTR_COOKIE] = {
795                 .type = NLA_BINARY,
796                 .len = 8,
797         },
798         [L2TP_ATTR_PEER_COOKIE] = {
799                 .type = NLA_BINARY,
800                 .len = 8,
801         },
802 };
803
804 static const struct genl_ops l2tp_nl_ops[] = {
805         {
806                 .cmd = L2TP_CMD_NOOP,
807                 .doit = l2tp_nl_cmd_noop,
808                 .policy = l2tp_nl_policy,
809                 /* can be retrieved by unprivileged users */
810         },
811         {
812                 .cmd = L2TP_CMD_TUNNEL_CREATE,
813                 .doit = l2tp_nl_cmd_tunnel_create,
814                 .policy = l2tp_nl_policy,
815                 .flags = GENL_ADMIN_PERM,
816         },
817         {
818                 .cmd = L2TP_CMD_TUNNEL_DELETE,
819                 .doit = l2tp_nl_cmd_tunnel_delete,
820                 .policy = l2tp_nl_policy,
821                 .flags = GENL_ADMIN_PERM,
822         },
823         {
824                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
825                 .doit = l2tp_nl_cmd_tunnel_modify,
826                 .policy = l2tp_nl_policy,
827                 .flags = GENL_ADMIN_PERM,
828         },
829         {
830                 .cmd = L2TP_CMD_TUNNEL_GET,
831                 .doit = l2tp_nl_cmd_tunnel_get,
832                 .dumpit = l2tp_nl_cmd_tunnel_dump,
833                 .policy = l2tp_nl_policy,
834                 .flags = GENL_ADMIN_PERM,
835         },
836         {
837                 .cmd = L2TP_CMD_SESSION_CREATE,
838                 .doit = l2tp_nl_cmd_session_create,
839                 .policy = l2tp_nl_policy,
840                 .flags = GENL_ADMIN_PERM,
841         },
842         {
843                 .cmd = L2TP_CMD_SESSION_DELETE,
844                 .doit = l2tp_nl_cmd_session_delete,
845                 .policy = l2tp_nl_policy,
846                 .flags = GENL_ADMIN_PERM,
847         },
848         {
849                 .cmd = L2TP_CMD_SESSION_MODIFY,
850                 .doit = l2tp_nl_cmd_session_modify,
851                 .policy = l2tp_nl_policy,
852                 .flags = GENL_ADMIN_PERM,
853         },
854         {
855                 .cmd = L2TP_CMD_SESSION_GET,
856                 .doit = l2tp_nl_cmd_session_get,
857                 .dumpit = l2tp_nl_cmd_session_dump,
858                 .policy = l2tp_nl_policy,
859                 .flags = GENL_ADMIN_PERM,
860         },
861 };
862
863 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
864 {
865         int ret;
866
867         ret = -EINVAL;
868         if (pw_type >= __L2TP_PWTYPE_MAX)
869                 goto err;
870
871         genl_lock();
872         ret = -EBUSY;
873         if (l2tp_nl_cmd_ops[pw_type])
874                 goto out;
875
876         l2tp_nl_cmd_ops[pw_type] = ops;
877         ret = 0;
878
879 out:
880         genl_unlock();
881 err:
882         return ret;
883 }
884 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
885
886 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
887 {
888         if (pw_type < __L2TP_PWTYPE_MAX) {
889                 genl_lock();
890                 l2tp_nl_cmd_ops[pw_type] = NULL;
891                 genl_unlock();
892         }
893 }
894 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
895
896 static int l2tp_nl_init(void)
897 {
898         pr_info("L2TP netlink interface\n");
899         return genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops);
900 }
901
902 static void l2tp_nl_cleanup(void)
903 {
904         genl_unregister_family(&l2tp_nl_family);
905 }
906
907 module_init(l2tp_nl_init);
908 module_exit(l2tp_nl_cleanup);
909
910 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
911 MODULE_DESCRIPTION("L2TP netlink");
912 MODULE_LICENSE("GPL");
913 MODULE_VERSION("1.0");
914 MODULE_ALIAS_GENL_FAMILY("l2tp");