kernel/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 static const struct genl_multicast_group l2tp_multicast_group[] = {
  44         {
  45                 .name = L2TP_GENL_MCGROUP,
  46         },
  47 };
  48
  49 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq,
  50                                int flags, struct l2tp_tunnel *tunnel, u8 cmd);
  51 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq,
  52                                 int flags, struct l2tp_session *session,
  53                                 u8 cmd);
  54
  55 /* Accessed under genl lock */
  56 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
  57
  58 static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info)
  59 {
  60         u32 tunnel_id;
  61         u32 session_id;
  62         char *ifname;
  63         struct l2tp_tunnel *tunnel;
  64         struct l2tp_session *session = NULL;
  65         struct net *net = genl_info_net(info);
  66
  67         if (info->attrs[L2TP_ATTR_IFNAME]) {
  68                 ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
  69                 session = l2tp_session_find_by_ifname(net, ifname);
  70         } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
  71                    (info->attrs[L2TP_ATTR_CONN_ID])) {
  72                 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
  73                 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
  74                 tunnel = l2tp_tunnel_find(net, tunnel_id);
  75                 if (tunnel)
  76                         session = l2tp_session_find(net, tunnel, session_id);
  77         }
  78
  79         return session;
  80 }
  81
  82 static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
  83 {
  84         struct sk_buff *msg;
  85         void *hdr;
  86         int ret = -ENOBUFS;
  87
  88         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  89         if (!msg) {
  90                 ret = -ENOMEM;
  91                 goto out;
  92         }
  93
  94         hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
  95                           &l2tp_nl_family, 0, L2TP_CMD_NOOP);
  96         if (!hdr) {
  97                 ret = -EMSGSIZE;
  98                 goto err_out;
  99         }
 100
 101         genlmsg_end(msg, hdr);
 102
 103         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 104
 105 err_out:
 106         nlmsg_free(msg);
 107
 108 out:
 109         return ret;
 110 }
 111
 112 static int l2tp_tunnel_notify(struct genl_family *family,
 113                               struct genl_info *info,
 114                               struct l2tp_tunnel *tunnel,
 115                               u8 cmd)
 116 {
 117         struct sk_buff *msg;
 118         int ret;
 119
 120         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 121         if (!msg)
 122                 return -ENOMEM;
 123
 124         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 125                                   NLM_F_ACK, tunnel, cmd);
 126
 127         if (ret >= 0) {
 128                 ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
 129                 /* We don't care if no one is listening */
 130                 if (ret == -ESRCH)
 131                         ret = 0;
 132                 return ret;
 133         }
 134
 135         nlmsg_free(msg);
 136
 137         return ret;
 138 }
 139
 140 static int l2tp_session_notify(struct genl_family *family,
 141                                struct genl_info *info,
 142                                struct l2tp_session *session,
 143                                u8 cmd)
 144 {
 145         struct sk_buff *msg;
 146         int ret;
 147
 148         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 149         if (!msg)
 150                 return -ENOMEM;
 151
 152         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 153                                    NLM_F_ACK, session, cmd);
 154
 155         if (ret >= 0) {
 156                 ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
 157                 /* We don't care if no one is listening */
 158                 if (ret == -ESRCH)
 159                         ret = 0;
 160                 return ret;
 161         }
 162
 163         nlmsg_free(msg);
 164
 165         return ret;
 166 }
 167
 168 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
 169 {
 170         u32 tunnel_id;
 171         u32 peer_tunnel_id;
 172         int proto_version;
 173         int fd;
 174         int ret = 0;
 175         struct l2tp_tunnel_cfg cfg = { 0, };
 176         struct l2tp_tunnel *tunnel;
 177         struct net *net = genl_info_net(info);
 178
 179         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 180                 ret = -EINVAL;
 181                 goto out;
 182         }
 183         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 184
 185         if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
 186                 ret = -EINVAL;
 187                 goto out;
 188         }
 189         peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
 190
 191         if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
 192                 ret = -EINVAL;
 193                 goto out;
 194         }
 195         proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
 196
 197         if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
 198                 ret = -EINVAL;
 199                 goto out;
 200         }
 201         cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
 202
 203         fd = -1;
 204         if (info->attrs[L2TP_ATTR_FD]) {
 205                 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
 206         } else {
 207 #if IS_ENABLED(CONFIG_IPV6)
 208                 if (info->attrs[L2TP_ATTR_IP6_SADDR] &&
 209                     info->attrs[L2TP_ATTR_IP6_DADDR]) {
 210                         cfg.local_ip6 = nla_data(
 211                                 info->attrs[L2TP_ATTR_IP6_SADDR]);
 212                         cfg.peer_ip6 = nla_data(
 213                                 info->attrs[L2TP_ATTR_IP6_DADDR]);
 214                 } else
 215 #endif
 216                 if (info->attrs[L2TP_ATTR_IP_SADDR] &&
 217                     info->attrs[L2TP_ATTR_IP_DADDR]) {
 218                         cfg.local_ip.s_addr = nla_get_in_addr(
 219                                 info->attrs[L2TP_ATTR_IP_SADDR]);
 220                         cfg.peer_ip.s_addr = nla_get_in_addr(
 221                                 info->attrs[L2TP_ATTR_IP_DADDR]);
 222                 } else {
 223                         ret = -EINVAL;
 224                         goto out;
 225                 }
 226                 if (info->attrs[L2TP_ATTR_UDP_SPORT])
 227                         cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
 228                 if (info->attrs[L2TP_ATTR_UDP_DPORT])
 229                         cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
 230                 if (info->attrs[L2TP_ATTR_UDP_CSUM])
 231                         cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
 232
 233 #if IS_ENABLED(CONFIG_IPV6)
 234                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX])
 235                         cfg.udp6_zero_tx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
 236                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX])
 237                         cfg.udp6_zero_rx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
 238 #endif
 239         }
 240
 241         if (info->attrs[L2TP_ATTR_DEBUG])
 242                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 243
 244         tunnel = l2tp_tunnel_find(net, tunnel_id);
 245         if (tunnel != NULL) {
 246                 ret = -EEXIST;
 247                 goto out;
 248         }
 249
 250         ret = -EINVAL;
 251         switch (cfg.encap) {
 252         case L2TP_ENCAPTYPE_UDP:
 253         case L2TP_ENCAPTYPE_IP:
 254                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
 255                                          peer_tunnel_id, &cfg, &tunnel);
 256                 break;
 257         }
 258
 259         if (ret >= 0)
 260                 ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 261                                          tunnel, L2TP_CMD_TUNNEL_CREATE);
 262 out:
 263         return ret;
 264 }
 265
 266 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 267 {
 268         struct l2tp_tunnel *tunnel;
 269         u32 tunnel_id;
 270         int ret = 0;
 271         struct net *net = genl_info_net(info);
 272
 273         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 274                 ret = -EINVAL;
 275                 goto out;
 276         }
 277         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 278
 279         tunnel = l2tp_tunnel_find(net, tunnel_id);
 280         if (tunnel == NULL) {
 281                 ret = -ENODEV;
 282                 goto out;
 283         }
 284
 285         l2tp_tunnel_notify(&l2tp_nl_family, info,
 286                            tunnel, L2TP_CMD_TUNNEL_DELETE);
 287
 288         (void) l2tp_tunnel_delete(tunnel);
 289
 290 out:
 291         return ret;
 292 }
 293
 294 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 295 {
 296         struct l2tp_tunnel *tunnel;
 297         u32 tunnel_id;
 298         int ret = 0;
 299         struct net *net = genl_info_net(info);
 300
 301         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 302                 ret = -EINVAL;
 303                 goto out;
 304         }
 305         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 306
 307         tunnel = l2tp_tunnel_find(net, tunnel_id);
 308         if (tunnel == NULL) {
 309                 ret = -ENODEV;
 310                 goto out;
 311         }
 312
 313         if (info->attrs[L2TP_ATTR_DEBUG])
 314                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 315
 316         ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 317                                  tunnel, L2TP_CMD_TUNNEL_MODIFY);
 318
 319 out:
 320         return ret;
 321 }
 322
 323 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 324                                struct l2tp_tunnel *tunnel, u8 cmd)
 325 {
 326         void *hdr;
 327         struct nlattr *nest;
 328         struct sock *sk = NULL;
 329         struct inet_sock *inet;
 330 #if IS_ENABLED(CONFIG_IPV6)
 331         struct ipv6_pinfo *np = NULL;
 332 #endif
 333
 334         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 335         if (!hdr)
 336                 return -EMSGSIZE;
 337
 338         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 339             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 340             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 341             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
 342             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 343                 goto nla_put_failure;
 344
 345         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 346         if (nest == NULL)
 347                 goto nla_put_failure;
 348
 349         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 350                     atomic_long_read(&tunnel->stats.tx_packets)) ||
 351             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 352                     atomic_long_read(&tunnel->stats.tx_bytes)) ||
 353             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 354                     atomic_long_read(&tunnel->stats.tx_errors)) ||
 355             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 356                     atomic_long_read(&tunnel->stats.rx_packets)) ||
 357             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 358                     atomic_long_read(&tunnel->stats.rx_bytes)) ||
 359             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 360                     atomic_long_read(&tunnel->stats.rx_seq_discards)) ||
 361             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 362                     atomic_long_read(&tunnel->stats.rx_oos_packets)) ||
 363             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 364                     atomic_long_read(&tunnel->stats.rx_errors)))
 365                 goto nla_put_failure;
 366         nla_nest_end(skb, nest);
 367
 368         sk = tunnel->sock;
 369         if (!sk)
 370                 goto out;
 371
 372 #if IS_ENABLED(CONFIG_IPV6)
 373         if (sk->sk_family == AF_INET6)
 374                 np = inet6_sk(sk);
 375 #endif
 376
 377         inet = inet_sk(sk);
 378
 379         switch (tunnel->encap) {
 380         case L2TP_ENCAPTYPE_UDP:
 381                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 382                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
 383                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx))
 384                         goto nla_put_failure;
 385                 /* NOBREAK */
 386         case L2TP_ENCAPTYPE_IP:
 387 #if IS_ENABLED(CONFIG_IPV6)
 388                 if (np) {
 389                         if (nla_put_in6_addr(skb, L2TP_ATTR_IP6_SADDR,
 390                                              &np->saddr) ||
 391                             nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR,
 392                                              &sk->sk_v6_daddr))
 393                                 goto nla_put_failure;
 394                 } else
 395 #endif
 396                 if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR,
 397                                     inet->inet_saddr) ||
 398                     nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR,
 399                                     inet->inet_daddr))
 400                         goto nla_put_failure;
 401                 break;
 402         }
 403
 404 out:
 405         genlmsg_end(skb, hdr);
 406         return 0;
 407
 408 nla_put_failure:
 409         genlmsg_cancel(skb, hdr);
 410         return -1;
 411 }
 412
 413 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 414 {
 415         struct l2tp_tunnel *tunnel;
 416         struct sk_buff *msg;
 417         u32 tunnel_id;
 418         int ret = -ENOBUFS;
 419         struct net *net = genl_info_net(info);
 420
 421         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 422                 ret = -EINVAL;
 423                 goto out;
 424         }
 425
 426         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 427
 428         tunnel = l2tp_tunnel_find(net, tunnel_id);
 429         if (tunnel == NULL) {
 430                 ret = -ENODEV;
 431                 goto out;
 432         }
 433
 434         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 435         if (!msg) {
 436                 ret = -ENOMEM;
 437                 goto out;
 438         }
 439
 440         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 441                                   NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
 442         if (ret < 0)
 443                 goto err_out;
 444
 445         return genlmsg_unicast(net, msg, info->snd_portid);
 446
 447 err_out:
 448         nlmsg_free(msg);
 449
 450 out:
 451         return ret;
 452 }
 453
 454 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 455 {
 456         int ti = cb->args[0];
 457         struct l2tp_tunnel *tunnel;
 458         struct net *net = sock_net(skb->sk);
 459
 460         for (;;) {
 461                 tunnel = l2tp_tunnel_find_nth(net, ti);
 462                 if (tunnel == NULL)
 463                         goto out;
 464
 465                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 466                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 467                                         tunnel, L2TP_CMD_TUNNEL_GET) < 0)
 468                         goto out;
 469
 470                 ti++;
 471         }
 472
 473 out:
 474         cb->args[0] = ti;
 475
 476         return skb->len;
 477 }
 478
 479 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 480 {
 481         u32 tunnel_id = 0;
 482         u32 session_id;
 483         u32 peer_session_id;
 484         int ret = 0;
 485         struct l2tp_tunnel *tunnel;
 486         struct l2tp_session *session;
 487         struct l2tp_session_cfg cfg = { 0, };
 488         struct net *net = genl_info_net(info);
 489
 490         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 491                 ret = -EINVAL;
 492                 goto out;
 493         }
 494         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 495         tunnel = l2tp_tunnel_find(net, tunnel_id);
 496         if (!tunnel) {
 497                 ret = -ENODEV;
 498                 goto out;
 499         }
 500
 501         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 502                 ret = -EINVAL;
 503                 goto out;
 504         }
 505         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 506         session = l2tp_session_find(net, tunnel, session_id);
 507         if (session) {
 508                 ret = -EEXIST;
 509                 goto out;
 510         }
 511
 512         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 513                 ret = -EINVAL;
 514                 goto out;
 515         }
 516         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 517
 518         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 519                 ret = -EINVAL;
 520                 goto out;
 521         }
 522         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 523         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 524                 ret = -EINVAL;
 525                 goto out;
 526         }
 527
 528         if (tunnel->version > 2) {
 529                 if (info->attrs[L2TP_ATTR_OFFSET])
 530                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 531
 532                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 533                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 534
 535                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 536                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 537                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 538
 539                 cfg.l2specific_len = 4;
 540                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 541                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 542
 543                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 544                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 545                         if (len > 8) {
 546                                 ret = -EINVAL;
 547                                 goto out;
 548                         }
 549                         cfg.cookie_len = len;
 550                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 551                 }
 552                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 553                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 554                         if (len > 8) {
 555                                 ret = -EINVAL;
 556                                 goto out;
 557                         }
 558                         cfg.peer_cookie_len = len;
 559                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 560                 }
 561                 if (info->attrs[L2TP_ATTR_IFNAME])
 562                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 563
 564                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 565                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 566         }
 567
 568         if (info->attrs[L2TP_ATTR_DEBUG])
 569                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 570
 571         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 572                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 573
 574         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 575                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 576
 577         if (info->attrs[L2TP_ATTR_LNS_MODE])
 578                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 579
 580         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 581                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 582
 583         if (info->attrs[L2TP_ATTR_MTU])
 584                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 585
 586         if (info->attrs[L2TP_ATTR_MRU])
 587                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 588
 589 #ifdef CONFIG_MODULES
 590         if (l2tp_nl_cmd_ops[cfg.pw_type] == NULL) {
 591                 genl_unlock();
 592                 request_module("net-l2tp-type-%u", cfg.pw_type);
 593                 genl_lock();
 594         }
 595 #endif
 596         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 597             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 598                 ret = -EPROTONOSUPPORT;
 599                 goto out;
 600         }
 601
 602         /* Check that pseudowire-specific params are present */
 603         switch (cfg.pw_type) {
 604         case L2TP_PWTYPE_NONE:
 605                 break;
 606         case L2TP_PWTYPE_ETH_VLAN:
 607                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 608                         ret = -EINVAL;
 609                         goto out;
 610                 }
 611                 break;
 612         case L2TP_PWTYPE_ETH:
 613                 break;
 614         case L2TP_PWTYPE_PPP:
 615         case L2TP_PWTYPE_PPP_AC:
 616                 break;
 617         case L2TP_PWTYPE_IP:
 618         default:
 619                 ret = -EPROTONOSUPPORT;
 620                 break;
 621         }
 622
 623         ret = -EPROTONOSUPPORT;
 624         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 625                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 626                         session_id, peer_session_id, &cfg);
 627
 628         if (ret >= 0) {
 629                 session = l2tp_session_find(net, tunnel, session_id);
 630                 if (session)
 631                         ret = l2tp_session_notify(&l2tp_nl_family, info, session,
 632                                                   L2TP_CMD_SESSION_CREATE);
 633         }
 634
 635 out:
 636         return ret;
 637 }
 638
 639 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 640 {
 641         int ret = 0;
 642         struct l2tp_session *session;
 643         u16 pw_type;
 644
 645         session = l2tp_nl_session_find(info);
 646         if (session == NULL) {
 647                 ret = -ENODEV;
 648                 goto out;
 649         }
 650
 651         l2tp_session_notify(&l2tp_nl_family, info,
 652                             session, L2TP_CMD_SESSION_DELETE);
 653
 654         pw_type = session->pwtype;
 655         if (pw_type < __L2TP_PWTYPE_MAX)
 656                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 657                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 658
 659 out:
 660         return ret;
 661 }
 662
 663 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 664 {
 665         int ret = 0;
 666         struct l2tp_session *session;
 667
 668         session = l2tp_nl_session_find(info);
 669         if (session == NULL) {
 670                 ret = -ENODEV;
 671                 goto out;
 672         }
 673
 674         if (info->attrs[L2TP_ATTR_DEBUG])
 675                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 676
 677         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 678                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 679
 680         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 681                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 682
 683         if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 684                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 685                 l2tp_session_set_header_len(session, session->tunnel->version);
 686         }
 687
 688         if (info->attrs[L2TP_ATTR_LNS_MODE])
 689                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 690
 691         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 692                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 693
 694         if (info->attrs[L2TP_ATTR_MTU])
 695                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 696
 697         if (info->attrs[L2TP_ATTR_MRU])
 698                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 699
 700         ret = l2tp_session_notify(&l2tp_nl_family, info,
 701                                   session, L2TP_CMD_SESSION_MODIFY);
 702
 703 out:
 704         return ret;
 705 }
 706
 707 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 708                                 struct l2tp_session *session, u8 cmd)
 709 {
 710         void *hdr;
 711         struct nlattr *nest;
 712         struct l2tp_tunnel *tunnel = session->tunnel;
 713         struct sock *sk = NULL;
 714
 715         sk = tunnel->sock;
 716
 717         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 718         if (!hdr)
 719                 return -EMSGSIZE;
 720
 721         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 722             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 723             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 724             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
 725                         session->peer_session_id) ||
 726             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 727             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
 728             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
 729             (session->mru &&
 730              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
 731                 goto nla_put_failure;
 732
 733         if ((session->ifname[0] &&
 734              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 735             (session->cookie_len &&
 736              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
 737                      &session->cookie[0])) ||
 738             (session->peer_cookie_len &&
 739              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
 740                      &session->peer_cookie[0])) ||
 741             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 742             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 743             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 744 #ifdef CONFIG_XFRM
 745             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
 746              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 747 #endif
 748             (session->reorder_timeout &&
 749              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
 750                 goto nla_put_failure;
 751
 752         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 753         if (nest == NULL)
 754                 goto nla_put_failure;
 755
 756         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 757                 atomic_long_read(&session->stats.tx_packets)) ||
 758             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 759                 atomic_long_read(&session->stats.tx_bytes)) ||
 760             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 761                 atomic_long_read(&session->stats.tx_errors)) ||
 762             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 763                 atomic_long_read(&session->stats.rx_packets)) ||
 764             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 765                 atomic_long_read(&session->stats.rx_bytes)) ||
 766             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 767                 atomic_long_read(&session->stats.rx_seq_discards)) ||
 768             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 769                 atomic_long_read(&session->stats.rx_oos_packets)) ||
 770             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 771                 atomic_long_read(&session->stats.rx_errors)))
 772                 goto nla_put_failure;
 773         nla_nest_end(skb, nest);
 774
 775         genlmsg_end(skb, hdr);
 776         return 0;
 777
 778  nla_put_failure:
 779         genlmsg_cancel(skb, hdr);
 780         return -1;
 781 }
 782
 783 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 784 {
 785         struct l2tp_session *session;
 786         struct sk_buff *msg;
 787         int ret;
 788
 789         session = l2tp_nl_session_find(info);
 790         if (session == NULL) {
 791                 ret = -ENODEV;
 792                 goto out;
 793         }
 794
 795         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 796         if (!msg) {
 797                 ret = -ENOMEM;
 798                 goto out;
 799         }
 800
 801         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 802                                    0, session, L2TP_CMD_SESSION_GET);
 803         if (ret < 0)
 804                 goto err_out;
 805
 806         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 807
 808 err_out:
 809         nlmsg_free(msg);
 810
 811 out:
 812         return ret;
 813 }
 814
 815 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 816 {
 817         struct net *net = sock_net(skb->sk);
 818         struct l2tp_session *session;
 819         struct l2tp_tunnel *tunnel = NULL;
 820         int ti = cb->args[0];
 821         int si = cb->args[1];
 822
 823         for (;;) {
 824                 if (tunnel == NULL) {
 825                         tunnel = l2tp_tunnel_find_nth(net, ti);
 826                         if (tunnel == NULL)
 827                                 goto out;
 828                 }
 829
 830                 session = l2tp_session_find_nth(tunnel, si);
 831                 if (session == NULL) {
 832                         ti++;
 833                         tunnel = NULL;
 834                         si = 0;
 835                         continue;
 836                 }
 837
 838                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 839                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 840                                          session, L2TP_CMD_SESSION_GET) < 0)
 841                         break;
 842
 843                 si++;
 844         }
 845
 846 out:
 847         cb->args[0] = ti;
 848         cb->args[1] = si;
 849
 850         return skb->len;
 851 }
 852
 853 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 854         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 855         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 856         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 857         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 858         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 859         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 860         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 861         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 862         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 863         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 864         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 865         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 866         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 867         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 868         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 869         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 870         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 871         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 872         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 873         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 874         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 875         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 876         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 877         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 878         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 879         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 880         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 881         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 882         [L2TP_ATTR_IP6_SADDR] = {
 883                 .type = NLA_BINARY,
 884                 .len = sizeof(struct in6_addr),
 885         },
 886         [L2TP_ATTR_IP6_DADDR] = {
 887                 .type = NLA_BINARY,
 888                 .len = sizeof(struct in6_addr),
 889         },
 890         [L2TP_ATTR_IFNAME] = {
 891                 .type = NLA_NUL_STRING,
 892                 .len = IFNAMSIZ - 1,
 893         },
 894         [L2TP_ATTR_COOKIE] = {
 895                 .type = NLA_BINARY,
 896                 .len = 8,
 897         },
 898         [L2TP_ATTR_PEER_COOKIE] = {
 899                 .type = NLA_BINARY,
 900                 .len = 8,
 901         },
 902 };
 903
 904 static const struct genl_ops l2tp_nl_ops[] = {
 905         {
 906                 .cmd = L2TP_CMD_NOOP,
 907                 .doit = l2tp_nl_cmd_noop,
 908                 .policy = l2tp_nl_policy,
 909                 /* can be retrieved by unprivileged users */
 910         },
 911         {
 912                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 913                 .doit = l2tp_nl_cmd_tunnel_create,
 914                 .policy = l2tp_nl_policy,
 915                 .flags = GENL_ADMIN_PERM,
 916         },
 917         {
 918                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 919                 .doit = l2tp_nl_cmd_tunnel_delete,
 920                 .policy = l2tp_nl_policy,
 921                 .flags = GENL_ADMIN_PERM,
 922         },
 923         {
 924                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 925                 .doit = l2tp_nl_cmd_tunnel_modify,
 926                 .policy = l2tp_nl_policy,
 927                 .flags = GENL_ADMIN_PERM,
 928         },
 929         {
 930                 .cmd = L2TP_CMD_TUNNEL_GET,
 931                 .doit = l2tp_nl_cmd_tunnel_get,
 932                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 933                 .policy = l2tp_nl_policy,
 934                 .flags = GENL_ADMIN_PERM,
 935         },
 936         {
 937                 .cmd = L2TP_CMD_SESSION_CREATE,
 938                 .doit = l2tp_nl_cmd_session_create,
 939                 .policy = l2tp_nl_policy,
 940                 .flags = GENL_ADMIN_PERM,
 941         },
 942         {
 943                 .cmd = L2TP_CMD_SESSION_DELETE,
 944                 .doit = l2tp_nl_cmd_session_delete,
 945                 .policy = l2tp_nl_policy,
 946                 .flags = GENL_ADMIN_PERM,
 947         },
 948         {
 949                 .cmd = L2TP_CMD_SESSION_MODIFY,
 950                 .doit = l2tp_nl_cmd_session_modify,
 951                 .policy = l2tp_nl_policy,
 952                 .flags = GENL_ADMIN_PERM,
 953         },
 954         {
 955                 .cmd = L2TP_CMD_SESSION_GET,
 956                 .doit = l2tp_nl_cmd_session_get,
 957                 .dumpit = l2tp_nl_cmd_session_dump,
 958                 .policy = l2tp_nl_policy,
 959                 .flags = GENL_ADMIN_PERM,
 960         },
 961 };
 962
 963 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 964 {
 965         int ret;
 966
 967         ret = -EINVAL;
 968         if (pw_type >= __L2TP_PWTYPE_MAX)
 969                 goto err;
 970
 971         genl_lock();
 972         ret = -EBUSY;
 973         if (l2tp_nl_cmd_ops[pw_type])
 974                 goto out;
 975
 976         l2tp_nl_cmd_ops[pw_type] = ops;
 977         ret = 0;
 978
 979 out:
 980         genl_unlock();
 981 err:
 982         return ret;
 983 }
 984 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 985
 986 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 987 {
 988         if (pw_type < __L2TP_PWTYPE_MAX) {
 989                 genl_lock();
 990                 l2tp_nl_cmd_ops[pw_type] = NULL;
 991                 genl_unlock();
 992         }
 993 }
 994 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 995
 996 static int l2tp_nl_init(void)
 997 {
 998         pr_info("L2TP netlink interface\n");
 999         return genl_register_family_with_ops_groups(&l2tp_nl_family,
1000                                                     l2tp_nl_ops,
1001                                                     l2tp_multicast_group);
1002 }
1003
1004 static void l2tp_nl_cleanup(void)
1005 {
1006         genl_unregister_family(&l2tp_nl_family);
1007 }
1008
1009 module_init(l2tp_nl_init);
1010 module_exit(l2tp_nl_cleanup);
1011
1012 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1013 MODULE_DESCRIPTION("L2TP netlink");
1014 MODULE_LICENSE("GPL");
1015 MODULE_VERSION("1.0");
1016 MODULE_ALIAS_GENL_FAMILY("l2tp");