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 #include <net/sock.h>
  18 #include <net/genetlink.h>
  19 #include <net/udp.h>
  20 #include <linux/in.h>
  21 #include <linux/udp.h>
  22 #include <linux/socket.h>
  23 #include <linux/module.h>
  24 #include <linux/list.h>
  25 #include <net/net_namespace.h>
  26
  27 #include <linux/l2tp.h>
  28
  29 #include "l2tp_core.h"
  30
  31
  32 static struct genl_family l2tp_nl_family = {
  33         .id             = GENL_ID_GENERATE,
  34         .name           = L2TP_GENL_NAME,
  35         .version        = L2TP_GENL_VERSION,
  36         .hdrsize        = 0,
  37         .maxattr        = L2TP_ATTR_MAX,
  38 };
  39
  40 /* Accessed under genl lock */
  41 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
  42
  43 static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info)
  44 {
  45         u32 tunnel_id;
  46         u32 session_id;
  47         char *ifname;
  48         struct l2tp_tunnel *tunnel;
  49         struct l2tp_session *session = NULL;
  50         struct net *net = genl_info_net(info);
  51
  52         if (info->attrs[L2TP_ATTR_IFNAME]) {
  53                 ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
  54                 session = l2tp_session_find_by_ifname(net, ifname);
  55         } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
  56                    (info->attrs[L2TP_ATTR_CONN_ID])) {
  57                 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
  58                 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
  59                 tunnel = l2tp_tunnel_find(net, tunnel_id);
  60                 if (tunnel)
  61                         session = l2tp_session_find(net, tunnel, session_id);
  62         }
  63
  64         return session;
  65 }
  66
  67 static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
  68 {
  69         struct sk_buff *msg;
  70         void *hdr;
  71         int ret = -ENOBUFS;
  72
  73         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
  74         if (!msg) {
  75                 ret = -ENOMEM;
  76                 goto out;
  77         }
  78
  79         hdr = genlmsg_put(msg, info->snd_pid, info->snd_seq,
  80                           &l2tp_nl_family, 0, L2TP_CMD_NOOP);
  81         if (IS_ERR(hdr)) {
  82                 ret = PTR_ERR(hdr);
  83                 goto err_out;
  84         }
  85
  86         genlmsg_end(msg, hdr);
  87
  88         return genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
  89
  90 err_out:
  91         nlmsg_free(msg);
  92
  93 out:
  94         return ret;
  95 }
  96
  97 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
  98 {
  99         u32 tunnel_id;
 100         u32 peer_tunnel_id;
 101         int proto_version;
 102         int fd;
 103         int ret = 0;
 104         struct l2tp_tunnel_cfg cfg = { 0, };
 105         struct l2tp_tunnel *tunnel;
 106         struct net *net = genl_info_net(info);
 107
 108         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 109                 ret = -EINVAL;
 110                 goto out;
 111         }
 112         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 113
 114         if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
 115                 ret = -EINVAL;
 116                 goto out;
 117         }
 118         peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
 119
 120         if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
 121                 ret = -EINVAL;
 122                 goto out;
 123         }
 124         proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
 125
 126         if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
 127                 ret = -EINVAL;
 128                 goto out;
 129         }
 130         cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
 131
 132         fd = -1;
 133         if (info->attrs[L2TP_ATTR_FD]) {
 134                 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
 135         } else {
 136                 if (info->attrs[L2TP_ATTR_IP_SADDR])
 137                         cfg.local_ip.s_addr = nla_get_be32(info->attrs[L2TP_ATTR_IP_SADDR]);
 138                 if (info->attrs[L2TP_ATTR_IP_DADDR])
 139                         cfg.peer_ip.s_addr = nla_get_be32(info->attrs[L2TP_ATTR_IP_DADDR]);
 140                 if (info->attrs[L2TP_ATTR_UDP_SPORT])
 141                         cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
 142                 if (info->attrs[L2TP_ATTR_UDP_DPORT])
 143                         cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
 144                 if (info->attrs[L2TP_ATTR_UDP_CSUM])
 145                         cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
 146         }
 147
 148         if (info->attrs[L2TP_ATTR_DEBUG])
 149                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 150
 151         tunnel = l2tp_tunnel_find(net, tunnel_id);
 152         if (tunnel != NULL) {
 153                 ret = -EEXIST;
 154                 goto out;
 155         }
 156
 157         ret = -EINVAL;
 158         switch (cfg.encap) {
 159         case L2TP_ENCAPTYPE_UDP:
 160         case L2TP_ENCAPTYPE_IP:
 161                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
 162                                          peer_tunnel_id, &cfg, &tunnel);
 163                 break;
 164         }
 165
 166 out:
 167         return ret;
 168 }
 169
 170 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 171 {
 172         struct l2tp_tunnel *tunnel;
 173         u32 tunnel_id;
 174         int ret = 0;
 175         struct net *net = genl_info_net(info);
 176
 177         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 178                 ret = -EINVAL;
 179                 goto out;
 180         }
 181         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 182
 183         tunnel = l2tp_tunnel_find(net, tunnel_id);
 184         if (tunnel == NULL) {
 185                 ret = -ENODEV;
 186                 goto out;
 187         }
 188
 189         (void) l2tp_tunnel_delete(tunnel);
 190
 191 out:
 192         return ret;
 193 }
 194
 195 static int l2tp_nl_cmd_tunnel_modify(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         if (info->attrs[L2TP_ATTR_DEBUG])
 215                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 216
 217 out:
 218         return ret;
 219 }
 220
 221 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 pid, u32 seq, int flags,
 222                                struct l2tp_tunnel *tunnel)
 223 {
 224         void *hdr;
 225         struct nlattr *nest;
 226         struct sock *sk = NULL;
 227         struct inet_sock *inet;
 228
 229         hdr = genlmsg_put(skb, pid, seq, &l2tp_nl_family, flags,
 230                           L2TP_CMD_TUNNEL_GET);
 231         if (IS_ERR(hdr))
 232                 return PTR_ERR(hdr);
 233
 234         NLA_PUT_U8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version);
 235         NLA_PUT_U32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id);
 236         NLA_PUT_U32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id);
 237         NLA_PUT_U32(skb, L2TP_ATTR_DEBUG, tunnel->debug);
 238         NLA_PUT_U16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap);
 239
 240         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 241         if (nest == NULL)
 242                 goto nla_put_failure;
 243
 244         NLA_PUT_U64(skb, L2TP_ATTR_TX_PACKETS, tunnel->stats.tx_packets);
 245         NLA_PUT_U64(skb, L2TP_ATTR_TX_BYTES, tunnel->stats.tx_bytes);
 246         NLA_PUT_U64(skb, L2TP_ATTR_TX_ERRORS, tunnel->stats.tx_errors);
 247         NLA_PUT_U64(skb, L2TP_ATTR_RX_PACKETS, tunnel->stats.rx_packets);
 248         NLA_PUT_U64(skb, L2TP_ATTR_RX_BYTES, tunnel->stats.rx_bytes);
 249         NLA_PUT_U64(skb, L2TP_ATTR_RX_SEQ_DISCARDS, tunnel->stats.rx_seq_discards);
 250         NLA_PUT_U64(skb, L2TP_ATTR_RX_OOS_PACKETS, tunnel->stats.rx_oos_packets);
 251         NLA_PUT_U64(skb, L2TP_ATTR_RX_ERRORS, tunnel->stats.rx_errors);
 252         nla_nest_end(skb, nest);
 253
 254         sk = tunnel->sock;
 255         if (!sk)
 256                 goto out;
 257
 258         inet = inet_sk(sk);
 259
 260         switch (tunnel->encap) {
 261         case L2TP_ENCAPTYPE_UDP:
 262                 NLA_PUT_U16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport));
 263                 NLA_PUT_U16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport));
 264                 NLA_PUT_U8(skb, L2TP_ATTR_UDP_CSUM, (sk->sk_no_check != UDP_CSUM_NOXMIT));
 265                 /* NOBREAK */
 266         case L2TP_ENCAPTYPE_IP:
 267                 NLA_PUT_BE32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr);
 268                 NLA_PUT_BE32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr);
 269                 break;
 270         }
 271
 272 out:
 273         return genlmsg_end(skb, hdr);
 274
 275 nla_put_failure:
 276         genlmsg_cancel(skb, hdr);
 277         return -1;
 278 }
 279
 280 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 281 {
 282         struct l2tp_tunnel *tunnel;
 283         struct sk_buff *msg;
 284         u32 tunnel_id;
 285         int ret = -ENOBUFS;
 286         struct net *net = genl_info_net(info);
 287
 288         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 289                 ret = -EINVAL;
 290                 goto out;
 291         }
 292
 293         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 294
 295         tunnel = l2tp_tunnel_find(net, tunnel_id);
 296         if (tunnel == NULL) {
 297                 ret = -ENODEV;
 298                 goto out;
 299         }
 300
 301         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 302         if (!msg) {
 303                 ret = -ENOMEM;
 304                 goto out;
 305         }
 306
 307         ret = l2tp_nl_tunnel_send(msg, info->snd_pid, info->snd_seq,
 308                                   NLM_F_ACK, tunnel);
 309         if (ret < 0)
 310                 goto err_out;
 311
 312         return genlmsg_unicast(net, msg, info->snd_pid);
 313
 314 err_out:
 315         nlmsg_free(msg);
 316
 317 out:
 318         return ret;
 319 }
 320
 321 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 322 {
 323         int ti = cb->args[0];
 324         struct l2tp_tunnel *tunnel;
 325         struct net *net = sock_net(skb->sk);
 326
 327         for (;;) {
 328                 tunnel = l2tp_tunnel_find_nth(net, ti);
 329                 if (tunnel == NULL)
 330                         goto out;
 331
 332                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).pid,
 333                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 334                                         tunnel) <= 0)
 335                         goto out;
 336
 337                 ti++;
 338         }
 339
 340 out:
 341         cb->args[0] = ti;
 342
 343         return skb->len;
 344 }
 345
 346 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 347 {
 348         u32 tunnel_id = 0;
 349         u32 session_id;
 350         u32 peer_session_id;
 351         int ret = 0;
 352         struct l2tp_tunnel *tunnel;
 353         struct l2tp_session *session;
 354         struct l2tp_session_cfg cfg = { 0, };
 355         struct net *net = genl_info_net(info);
 356
 357         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 358                 ret = -EINVAL;
 359                 goto out;
 360         }
 361         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 362         tunnel = l2tp_tunnel_find(net, tunnel_id);
 363         if (!tunnel) {
 364                 ret = -ENODEV;
 365                 goto out;
 366         }
 367
 368         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 369                 ret = -EINVAL;
 370                 goto out;
 371         }
 372         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 373         session = l2tp_session_find(net, tunnel, session_id);
 374         if (session) {
 375                 ret = -EEXIST;
 376                 goto out;
 377         }
 378
 379         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 380                 ret = -EINVAL;
 381                 goto out;
 382         }
 383         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 384
 385         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 386                 ret = -EINVAL;
 387                 goto out;
 388         }
 389         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 390         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 391                 ret = -EINVAL;
 392                 goto out;
 393         }
 394
 395         if (tunnel->version > 2) {
 396                 if (info->attrs[L2TP_ATTR_OFFSET])
 397                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 398
 399                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 400                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 401
 402                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 403                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 404                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 405
 406                 cfg.l2specific_len = 4;
 407                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 408                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 409
 410                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 411                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 412                         if (len > 8) {
 413                                 ret = -EINVAL;
 414                                 goto out;
 415                         }
 416                         cfg.cookie_len = len;
 417                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 418                 }
 419                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 420                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 421                         if (len > 8) {
 422                                 ret = -EINVAL;
 423                                 goto out;
 424                         }
 425                         cfg.peer_cookie_len = len;
 426                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 427                 }
 428                 if (info->attrs[L2TP_ATTR_IFNAME])
 429                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 430
 431                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 432                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 433         }
 434
 435         if (info->attrs[L2TP_ATTR_DEBUG])
 436                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 437
 438         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 439                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 440
 441         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 442                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 443
 444         if (info->attrs[L2TP_ATTR_LNS_MODE])
 445                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 446
 447         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 448                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 449
 450         if (info->attrs[L2TP_ATTR_MTU])
 451                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 452
 453         if (info->attrs[L2TP_ATTR_MRU])
 454                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 455
 456         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 457             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 458                 ret = -EPROTONOSUPPORT;
 459                 goto out;
 460         }
 461
 462         /* Check that pseudowire-specific params are present */
 463         switch (cfg.pw_type) {
 464         case L2TP_PWTYPE_NONE:
 465                 break;
 466         case L2TP_PWTYPE_ETH_VLAN:
 467                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 468                         ret = -EINVAL;
 469                         goto out;
 470                 }
 471                 break;
 472         case L2TP_PWTYPE_ETH:
 473                 break;
 474         case L2TP_PWTYPE_PPP:
 475         case L2TP_PWTYPE_PPP_AC:
 476                 break;
 477         case L2TP_PWTYPE_IP:
 478         default:
 479                 ret = -EPROTONOSUPPORT;
 480                 break;
 481         }
 482
 483         ret = -EPROTONOSUPPORT;
 484         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 485                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 486                         session_id, peer_session_id, &cfg);
 487
 488 out:
 489         return ret;
 490 }
 491
 492 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 493 {
 494         int ret = 0;
 495         struct l2tp_session *session;
 496         u16 pw_type;
 497
 498         session = l2tp_nl_session_find(info);
 499         if (session == NULL) {
 500                 ret = -ENODEV;
 501                 goto out;
 502         }
 503
 504         pw_type = session->pwtype;
 505         if (pw_type < __L2TP_PWTYPE_MAX)
 506                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 507                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 508
 509 out:
 510         return ret;
 511 }
 512
 513 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 514 {
 515         int ret = 0;
 516         struct l2tp_session *session;
 517
 518         session = l2tp_nl_session_find(info);
 519         if (session == NULL) {
 520                 ret = -ENODEV;
 521                 goto out;
 522         }
 523
 524         if (info->attrs[L2TP_ATTR_DEBUG])
 525                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 526
 527         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 528                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 529
 530         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 531                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 532
 533         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 534                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 535
 536         if (info->attrs[L2TP_ATTR_LNS_MODE])
 537                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 538
 539         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 540                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 541
 542         if (info->attrs[L2TP_ATTR_MTU])
 543                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 544
 545         if (info->attrs[L2TP_ATTR_MRU])
 546                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 547
 548 out:
 549         return ret;
 550 }
 551
 552 static int l2tp_nl_session_send(struct sk_buff *skb, u32 pid, u32 seq, int flags,
 553                                 struct l2tp_session *session)
 554 {
 555         void *hdr;
 556         struct nlattr *nest;
 557         struct l2tp_tunnel *tunnel = session->tunnel;
 558         struct sock *sk = NULL;
 559
 560         sk = tunnel->sock;
 561
 562         hdr = genlmsg_put(skb, pid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
 563         if (IS_ERR(hdr))
 564                 return PTR_ERR(hdr);
 565
 566         NLA_PUT_U32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id);
 567         NLA_PUT_U32(skb, L2TP_ATTR_SESSION_ID, session->session_id);
 568         NLA_PUT_U32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id);
 569         NLA_PUT_U32(skb, L2TP_ATTR_PEER_SESSION_ID, session->peer_session_id);
 570         NLA_PUT_U32(skb, L2TP_ATTR_DEBUG, session->debug);
 571         NLA_PUT_U16(skb, L2TP_ATTR_PW_TYPE, session->pwtype);
 572         NLA_PUT_U16(skb, L2TP_ATTR_MTU, session->mtu);
 573         if (session->mru)
 574                 NLA_PUT_U16(skb, L2TP_ATTR_MRU, session->mru);
 575
 576         if (session->ifname && session->ifname[0])
 577                 NLA_PUT_STRING(skb, L2TP_ATTR_IFNAME, session->ifname);
 578         if (session->cookie_len)
 579                 NLA_PUT(skb, L2TP_ATTR_COOKIE, session->cookie_len, &session->cookie[0]);
 580         if (session->peer_cookie_len)
 581                 NLA_PUT(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len, &session->peer_cookie[0]);
 582         NLA_PUT_U8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq);
 583         NLA_PUT_U8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq);
 584         NLA_PUT_U8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode);
 585 #ifdef CONFIG_XFRM
 586         if ((sk) && (sk->sk_policy[0] || sk->sk_policy[1]))
 587                 NLA_PUT_U8(skb, L2TP_ATTR_USING_IPSEC, 1);
 588 #endif
 589         if (session->reorder_timeout)
 590                 NLA_PUT_MSECS(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout);
 591
 592         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 593         if (nest == NULL)
 594                 goto nla_put_failure;
 595         NLA_PUT_U64(skb, L2TP_ATTR_TX_PACKETS, session->stats.tx_packets);
 596         NLA_PUT_U64(skb, L2TP_ATTR_TX_BYTES, session->stats.tx_bytes);
 597         NLA_PUT_U64(skb, L2TP_ATTR_TX_ERRORS, session->stats.tx_errors);
 598         NLA_PUT_U64(skb, L2TP_ATTR_RX_PACKETS, session->stats.rx_packets);
 599         NLA_PUT_U64(skb, L2TP_ATTR_RX_BYTES, session->stats.rx_bytes);
 600         NLA_PUT_U64(skb, L2TP_ATTR_RX_SEQ_DISCARDS, session->stats.rx_seq_discards);
 601         NLA_PUT_U64(skb, L2TP_ATTR_RX_OOS_PACKETS, session->stats.rx_oos_packets);
 602         NLA_PUT_U64(skb, L2TP_ATTR_RX_ERRORS, session->stats.rx_errors);
 603         nla_nest_end(skb, nest);
 604
 605         return genlmsg_end(skb, hdr);
 606
 607  nla_put_failure:
 608         genlmsg_cancel(skb, hdr);
 609         return -1;
 610 }
 611
 612 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 613 {
 614         struct l2tp_session *session;
 615         struct sk_buff *msg;
 616         int ret;
 617
 618         session = l2tp_nl_session_find(info);
 619         if (session == NULL) {
 620                 ret = -ENODEV;
 621                 goto out;
 622         }
 623
 624         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 625         if (!msg) {
 626                 ret = -ENOMEM;
 627                 goto out;
 628         }
 629
 630         ret = l2tp_nl_session_send(msg, info->snd_pid, info->snd_seq,
 631                                    0, session);
 632         if (ret < 0)
 633                 goto err_out;
 634
 635         return genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
 636
 637 err_out:
 638         nlmsg_free(msg);
 639
 640 out:
 641         return ret;
 642 }
 643
 644 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 645 {
 646         struct net *net = sock_net(skb->sk);
 647         struct l2tp_session *session;
 648         struct l2tp_tunnel *tunnel = NULL;
 649         int ti = cb->args[0];
 650         int si = cb->args[1];
 651
 652         for (;;) {
 653                 if (tunnel == NULL) {
 654                         tunnel = l2tp_tunnel_find_nth(net, ti);
 655                         if (tunnel == NULL)
 656                                 goto out;
 657                 }
 658
 659                 session = l2tp_session_find_nth(tunnel, si);
 660                 if (session == NULL) {
 661                         ti++;
 662                         tunnel = NULL;
 663                         si = 0;
 664                         continue;
 665                 }
 666
 667                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).pid,
 668                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 669                                          session) <= 0)
 670                         break;
 671
 672                 si++;
 673         }
 674
 675 out:
 676         cb->args[0] = ti;
 677         cb->args[1] = si;
 678
 679         return skb->len;
 680 }
 681
 682 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 683         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 684         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 685         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 686         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 687         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 688         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 689         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 690         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 691         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 692         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 693         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 694         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 695         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 696         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 697         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 698         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 699         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 700         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 701         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 702         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 703         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 704         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 705         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 706         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 707         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 708         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 709         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 710         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 711         [L2TP_ATTR_IFNAME] = {
 712                 .type = NLA_NUL_STRING,
 713                 .len = IFNAMSIZ - 1,
 714         },
 715         [L2TP_ATTR_COOKIE] = {
 716                 .type = NLA_BINARY,
 717                 .len = 8,
 718         },
 719         [L2TP_ATTR_PEER_COOKIE] = {
 720                 .type = NLA_BINARY,
 721                 .len = 8,
 722         },
 723 };
 724
 725 static struct genl_ops l2tp_nl_ops[] = {
 726         {
 727                 .cmd = L2TP_CMD_NOOP,
 728                 .doit = l2tp_nl_cmd_noop,
 729                 .policy = l2tp_nl_policy,
 730                 /* can be retrieved by unprivileged users */
 731         },
 732         {
 733                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 734                 .doit = l2tp_nl_cmd_tunnel_create,
 735                 .policy = l2tp_nl_policy,
 736                 .flags = GENL_ADMIN_PERM,
 737         },
 738         {
 739                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 740                 .doit = l2tp_nl_cmd_tunnel_delete,
 741                 .policy = l2tp_nl_policy,
 742                 .flags = GENL_ADMIN_PERM,
 743         },
 744         {
 745                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 746                 .doit = l2tp_nl_cmd_tunnel_modify,
 747                 .policy = l2tp_nl_policy,
 748                 .flags = GENL_ADMIN_PERM,
 749         },
 750         {
 751                 .cmd = L2TP_CMD_TUNNEL_GET,
 752                 .doit = l2tp_nl_cmd_tunnel_get,
 753                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 754                 .policy = l2tp_nl_policy,
 755                 .flags = GENL_ADMIN_PERM,
 756         },
 757         {
 758                 .cmd = L2TP_CMD_SESSION_CREATE,
 759                 .doit = l2tp_nl_cmd_session_create,
 760                 .policy = l2tp_nl_policy,
 761                 .flags = GENL_ADMIN_PERM,
 762         },
 763         {
 764                 .cmd = L2TP_CMD_SESSION_DELETE,
 765                 .doit = l2tp_nl_cmd_session_delete,
 766                 .policy = l2tp_nl_policy,
 767                 .flags = GENL_ADMIN_PERM,
 768         },
 769         {
 770                 .cmd = L2TP_CMD_SESSION_MODIFY,
 771                 .doit = l2tp_nl_cmd_session_modify,
 772                 .policy = l2tp_nl_policy,
 773                 .flags = GENL_ADMIN_PERM,
 774         },
 775         {
 776                 .cmd = L2TP_CMD_SESSION_GET,
 777                 .doit = l2tp_nl_cmd_session_get,
 778                 .dumpit = l2tp_nl_cmd_session_dump,
 779                 .policy = l2tp_nl_policy,
 780                 .flags = GENL_ADMIN_PERM,
 781         },
 782 };
 783
 784 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 785 {
 786         int ret;
 787
 788         ret = -EINVAL;
 789         if (pw_type >= __L2TP_PWTYPE_MAX)
 790                 goto err;
 791
 792         genl_lock();
 793         ret = -EBUSY;
 794         if (l2tp_nl_cmd_ops[pw_type])
 795                 goto out;
 796
 797         l2tp_nl_cmd_ops[pw_type] = ops;
 798
 799 out:
 800         genl_unlock();
 801 err:
 802         return 0;
 803 }
 804 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 805
 806 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 807 {
 808         if (pw_type < __L2TP_PWTYPE_MAX) {
 809                 genl_lock();
 810                 l2tp_nl_cmd_ops[pw_type] = NULL;
 811                 genl_unlock();
 812         }
 813 }
 814 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 815
 816 static int l2tp_nl_init(void)
 817 {
 818         int err;
 819
 820         printk(KERN_INFO "L2TP netlink interface\n");
 821         err = genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops,
 822                                             ARRAY_SIZE(l2tp_nl_ops));
 823
 824         return err;
 825 }
 826
 827 static void l2tp_nl_cleanup(void)
 828 {
 829         genl_unregister_family(&l2tp_nl_family);
 830 }
 831
 832 module_init(l2tp_nl_init);
 833 module_exit(l2tp_nl_cleanup);
 834
 835 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 836 MODULE_DESCRIPTION("L2TP netlink");
 837 MODULE_LICENSE("GPL");
 838 MODULE_VERSION("1.0");
 839 MODULE_ALIAS("net-pf-" __stringify(PF_NETLINK) "-proto-" \
 840              __stringify(NETLINK_GENERIC) "-type-" "l2tp");