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                 return genlmsg_multicast_allns(family, msg, 0,  0, GFP_ATOMIC);
 129
 130         nlmsg_free(msg);
 131
 132         return ret;
 133 }
 134
 135 static int l2tp_session_notify(struct genl_family *family,
 136                                struct genl_info *info,
 137                                struct l2tp_session *session,
 138                                u8 cmd)
 139 {
 140         struct sk_buff *msg;
 141         int ret;
 142
 143         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 144         if (!msg)
 145                 return -ENOMEM;
 146
 147         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 148                                    NLM_F_ACK, session, cmd);
 149
 150         if (ret >= 0)
 151                 return genlmsg_multicast_allns(family, msg, 0,  0, GFP_ATOMIC);
 152
 153         nlmsg_free(msg);
 154
 155         return ret;
 156 }
 157
 158 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
 159 {
 160         u32 tunnel_id;
 161         u32 peer_tunnel_id;
 162         int proto_version;
 163         int fd;
 164         int ret = 0;
 165         struct l2tp_tunnel_cfg cfg = { 0, };
 166         struct l2tp_tunnel *tunnel;
 167         struct net *net = genl_info_net(info);
 168
 169         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 170                 ret = -EINVAL;
 171                 goto out;
 172         }
 173         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 174
 175         if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
 176                 ret = -EINVAL;
 177                 goto out;
 178         }
 179         peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
 180
 181         if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
 182                 ret = -EINVAL;
 183                 goto out;
 184         }
 185         proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
 186
 187         if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
 188                 ret = -EINVAL;
 189                 goto out;
 190         }
 191         cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
 192
 193         fd = -1;
 194         if (info->attrs[L2TP_ATTR_FD]) {
 195                 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
 196         } else {
 197 #if IS_ENABLED(CONFIG_IPV6)
 198                 if (info->attrs[L2TP_ATTR_IP6_SADDR] &&
 199                     info->attrs[L2TP_ATTR_IP6_DADDR]) {
 200                         cfg.local_ip6 = nla_data(
 201                                 info->attrs[L2TP_ATTR_IP6_SADDR]);
 202                         cfg.peer_ip6 = nla_data(
 203                                 info->attrs[L2TP_ATTR_IP6_DADDR]);
 204                 } else
 205 #endif
 206                 if (info->attrs[L2TP_ATTR_IP_SADDR] &&
 207                     info->attrs[L2TP_ATTR_IP_DADDR]) {
 208                         cfg.local_ip.s_addr = nla_get_be32(
 209                                 info->attrs[L2TP_ATTR_IP_SADDR]);
 210                         cfg.peer_ip.s_addr = nla_get_be32(
 211                                 info->attrs[L2TP_ATTR_IP_DADDR]);
 212                 } else {
 213                         ret = -EINVAL;
 214                         goto out;
 215                 }
 216                 if (info->attrs[L2TP_ATTR_UDP_SPORT])
 217                         cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
 218                 if (info->attrs[L2TP_ATTR_UDP_DPORT])
 219                         cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
 220                 if (info->attrs[L2TP_ATTR_UDP_CSUM])
 221                         cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
 222
 223 #if IS_ENABLED(CONFIG_IPV6)
 224                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX])
 225                         cfg.udp6_zero_tx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
 226                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX])
 227                         cfg.udp6_zero_rx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
 228 #endif
 229         }
 230
 231         if (info->attrs[L2TP_ATTR_DEBUG])
 232                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 233
 234         tunnel = l2tp_tunnel_find(net, tunnel_id);
 235         if (tunnel != NULL) {
 236                 ret = -EEXIST;
 237                 goto out;
 238         }
 239
 240         ret = -EINVAL;
 241         switch (cfg.encap) {
 242         case L2TP_ENCAPTYPE_UDP:
 243         case L2TP_ENCAPTYPE_IP:
 244                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
 245                                          peer_tunnel_id, &cfg, &tunnel);
 246                 break;
 247         }
 248
 249         if (ret >= 0)
 250                 ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 251                                          tunnel, L2TP_CMD_TUNNEL_CREATE);
 252 out:
 253         return ret;
 254 }
 255
 256 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 257 {
 258         struct l2tp_tunnel *tunnel;
 259         u32 tunnel_id;
 260         int ret = 0;
 261         struct net *net = genl_info_net(info);
 262
 263         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 264                 ret = -EINVAL;
 265                 goto out;
 266         }
 267         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 268
 269         tunnel = l2tp_tunnel_find(net, tunnel_id);
 270         if (tunnel == NULL) {
 271                 ret = -ENODEV;
 272                 goto out;
 273         }
 274
 275         l2tp_tunnel_notify(&l2tp_nl_family, info,
 276                            tunnel, L2TP_CMD_TUNNEL_DELETE);
 277
 278         (void) l2tp_tunnel_delete(tunnel);
 279
 280 out:
 281         return ret;
 282 }
 283
 284 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 285 {
 286         struct l2tp_tunnel *tunnel;
 287         u32 tunnel_id;
 288         int ret = 0;
 289         struct net *net = genl_info_net(info);
 290
 291         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 292                 ret = -EINVAL;
 293                 goto out;
 294         }
 295         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 296
 297         tunnel = l2tp_tunnel_find(net, tunnel_id);
 298         if (tunnel == NULL) {
 299                 ret = -ENODEV;
 300                 goto out;
 301         }
 302
 303         if (info->attrs[L2TP_ATTR_DEBUG])
 304                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 305
 306         ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 307                                  tunnel, L2TP_CMD_TUNNEL_MODIFY);
 308
 309 out:
 310         return ret;
 311 }
 312
 313 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 314                                struct l2tp_tunnel *tunnel, u8 cmd)
 315 {
 316         void *hdr;
 317         struct nlattr *nest;
 318         struct sock *sk = NULL;
 319         struct inet_sock *inet;
 320 #if IS_ENABLED(CONFIG_IPV6)
 321         struct ipv6_pinfo *np = NULL;
 322 #endif
 323
 324         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 325         if (!hdr)
 326                 return -EMSGSIZE;
 327
 328         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 329             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 330             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 331             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
 332             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 333                 goto nla_put_failure;
 334
 335         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 336         if (nest == NULL)
 337                 goto nla_put_failure;
 338
 339         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 340                     atomic_long_read(&tunnel->stats.tx_packets)) ||
 341             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 342                     atomic_long_read(&tunnel->stats.tx_bytes)) ||
 343             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 344                     atomic_long_read(&tunnel->stats.tx_errors)) ||
 345             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 346                     atomic_long_read(&tunnel->stats.rx_packets)) ||
 347             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 348                     atomic_long_read(&tunnel->stats.rx_bytes)) ||
 349             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 350                     atomic_long_read(&tunnel->stats.rx_seq_discards)) ||
 351             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 352                     atomic_long_read(&tunnel->stats.rx_oos_packets)) ||
 353             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 354                     atomic_long_read(&tunnel->stats.rx_errors)))
 355                 goto nla_put_failure;
 356         nla_nest_end(skb, nest);
 357
 358         sk = tunnel->sock;
 359         if (!sk)
 360                 goto out;
 361
 362 #if IS_ENABLED(CONFIG_IPV6)
 363         if (sk->sk_family == AF_INET6)
 364                 np = inet6_sk(sk);
 365 #endif
 366
 367         inet = inet_sk(sk);
 368
 369         switch (tunnel->encap) {
 370         case L2TP_ENCAPTYPE_UDP:
 371                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 372                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
 373                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx))
 374                         goto nla_put_failure;
 375                 /* NOBREAK */
 376         case L2TP_ENCAPTYPE_IP:
 377 #if IS_ENABLED(CONFIG_IPV6)
 378                 if (np) {
 379                         if (nla_put(skb, L2TP_ATTR_IP6_SADDR, sizeof(np->saddr),
 380                                     &np->saddr) ||
 381                             nla_put(skb, L2TP_ATTR_IP6_DADDR, sizeof(sk->sk_v6_daddr),
 382                                     &sk->sk_v6_daddr))
 383                                 goto nla_put_failure;
 384                 } else
 385 #endif
 386                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 387                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 388                         goto nla_put_failure;
 389                 break;
 390         }
 391
 392 out:
 393         return genlmsg_end(skb, hdr);
 394
 395 nla_put_failure:
 396         genlmsg_cancel(skb, hdr);
 397         return -1;
 398 }
 399
 400 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 401 {
 402         struct l2tp_tunnel *tunnel;
 403         struct sk_buff *msg;
 404         u32 tunnel_id;
 405         int ret = -ENOBUFS;
 406         struct net *net = genl_info_net(info);
 407
 408         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 409                 ret = -EINVAL;
 410                 goto out;
 411         }
 412
 413         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 414
 415         tunnel = l2tp_tunnel_find(net, tunnel_id);
 416         if (tunnel == NULL) {
 417                 ret = -ENODEV;
 418                 goto out;
 419         }
 420
 421         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 422         if (!msg) {
 423                 ret = -ENOMEM;
 424                 goto out;
 425         }
 426
 427         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 428                                   NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
 429         if (ret < 0)
 430                 goto err_out;
 431
 432         return genlmsg_unicast(net, msg, info->snd_portid);
 433
 434 err_out:
 435         nlmsg_free(msg);
 436
 437 out:
 438         return ret;
 439 }
 440
 441 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 442 {
 443         int ti = cb->args[0];
 444         struct l2tp_tunnel *tunnel;
 445         struct net *net = sock_net(skb->sk);
 446
 447         for (;;) {
 448                 tunnel = l2tp_tunnel_find_nth(net, ti);
 449                 if (tunnel == NULL)
 450                         goto out;
 451
 452                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 453                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 454                                         tunnel, L2TP_CMD_TUNNEL_GET) <= 0)
 455                         goto out;
 456
 457                 ti++;
 458         }
 459
 460 out:
 461         cb->args[0] = ti;
 462
 463         return skb->len;
 464 }
 465
 466 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 467 {
 468         u32 tunnel_id = 0;
 469         u32 session_id;
 470         u32 peer_session_id;
 471         int ret = 0;
 472         struct l2tp_tunnel *tunnel;
 473         struct l2tp_session *session;
 474         struct l2tp_session_cfg cfg = { 0, };
 475         struct net *net = genl_info_net(info);
 476
 477         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 478                 ret = -EINVAL;
 479                 goto out;
 480         }
 481         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 482         tunnel = l2tp_tunnel_find(net, tunnel_id);
 483         if (!tunnel) {
 484                 ret = -ENODEV;
 485                 goto out;
 486         }
 487
 488         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 489                 ret = -EINVAL;
 490                 goto out;
 491         }
 492         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 493         session = l2tp_session_find(net, tunnel, session_id);
 494         if (session) {
 495                 ret = -EEXIST;
 496                 goto out;
 497         }
 498
 499         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 500                 ret = -EINVAL;
 501                 goto out;
 502         }
 503         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 504
 505         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 506                 ret = -EINVAL;
 507                 goto out;
 508         }
 509         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 510         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 511                 ret = -EINVAL;
 512                 goto out;
 513         }
 514
 515         if (tunnel->version > 2) {
 516                 if (info->attrs[L2TP_ATTR_OFFSET])
 517                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 518
 519                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 520                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 521
 522                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 523                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 524                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 525
 526                 cfg.l2specific_len = 4;
 527                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 528                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 529
 530                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 531                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 532                         if (len > 8) {
 533                                 ret = -EINVAL;
 534                                 goto out;
 535                         }
 536                         cfg.cookie_len = len;
 537                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 538                 }
 539                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 540                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 541                         if (len > 8) {
 542                                 ret = -EINVAL;
 543                                 goto out;
 544                         }
 545                         cfg.peer_cookie_len = len;
 546                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 547                 }
 548                 if (info->attrs[L2TP_ATTR_IFNAME])
 549                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 550
 551                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 552                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 553         }
 554
 555         if (info->attrs[L2TP_ATTR_DEBUG])
 556                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 557
 558         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 559                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 560
 561         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 562                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 563
 564         if (info->attrs[L2TP_ATTR_LNS_MODE])
 565                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 566
 567         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 568                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 569
 570         if (info->attrs[L2TP_ATTR_MTU])
 571                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 572
 573         if (info->attrs[L2TP_ATTR_MRU])
 574                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 575
 576         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 577             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 578                 ret = -EPROTONOSUPPORT;
 579                 goto out;
 580         }
 581
 582         /* Check that pseudowire-specific params are present */
 583         switch (cfg.pw_type) {
 584         case L2TP_PWTYPE_NONE:
 585                 break;
 586         case L2TP_PWTYPE_ETH_VLAN:
 587                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 588                         ret = -EINVAL;
 589                         goto out;
 590                 }
 591                 break;
 592         case L2TP_PWTYPE_ETH:
 593                 break;
 594         case L2TP_PWTYPE_PPP:
 595         case L2TP_PWTYPE_PPP_AC:
 596                 break;
 597         case L2TP_PWTYPE_IP:
 598         default:
 599                 ret = -EPROTONOSUPPORT;
 600                 break;
 601         }
 602
 603         ret = -EPROTONOSUPPORT;
 604         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 605                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 606                         session_id, peer_session_id, &cfg);
 607
 608         if (ret >= 0) {
 609                 session = l2tp_session_find(net, tunnel, session_id);
 610                 if (session)
 611                         ret = l2tp_session_notify(&l2tp_nl_family, info, session,
 612                                                   L2TP_CMD_SESSION_CREATE);
 613         }
 614
 615 out:
 616         return ret;
 617 }
 618
 619 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 620 {
 621         int ret = 0;
 622         struct l2tp_session *session;
 623         u16 pw_type;
 624
 625         session = l2tp_nl_session_find(info);
 626         if (session == NULL) {
 627                 ret = -ENODEV;
 628                 goto out;
 629         }
 630
 631         l2tp_session_notify(&l2tp_nl_family, info,
 632                             session, L2TP_CMD_SESSION_DELETE);
 633
 634         pw_type = session->pwtype;
 635         if (pw_type < __L2TP_PWTYPE_MAX)
 636                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 637                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 638
 639 out:
 640         return ret;
 641 }
 642
 643 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 644 {
 645         int ret = 0;
 646         struct l2tp_session *session;
 647
 648         session = l2tp_nl_session_find(info);
 649         if (session == NULL) {
 650                 ret = -ENODEV;
 651                 goto out;
 652         }
 653
 654         if (info->attrs[L2TP_ATTR_DEBUG])
 655                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 656
 657         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 658                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 659
 660         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 661                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 662
 663         if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 664                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 665                 l2tp_session_set_header_len(session, session->tunnel->version);
 666         }
 667
 668         if (info->attrs[L2TP_ATTR_LNS_MODE])
 669                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 670
 671         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 672                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 673
 674         if (info->attrs[L2TP_ATTR_MTU])
 675                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 676
 677         if (info->attrs[L2TP_ATTR_MRU])
 678                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 679
 680         ret = l2tp_session_notify(&l2tp_nl_family, info,
 681                                   session, L2TP_CMD_SESSION_MODIFY);
 682
 683 out:
 684         return ret;
 685 }
 686
 687 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 688                                 struct l2tp_session *session, u8 cmd)
 689 {
 690         void *hdr;
 691         struct nlattr *nest;
 692         struct l2tp_tunnel *tunnel = session->tunnel;
 693         struct sock *sk = NULL;
 694
 695         sk = tunnel->sock;
 696
 697         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 698         if (!hdr)
 699                 return -EMSGSIZE;
 700
 701         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 702             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 703             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 704             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
 705                         session->peer_session_id) ||
 706             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 707             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
 708             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
 709             (session->mru &&
 710              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
 711                 goto nla_put_failure;
 712
 713         if ((session->ifname[0] &&
 714              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 715             (session->cookie_len &&
 716              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
 717                      &session->cookie[0])) ||
 718             (session->peer_cookie_len &&
 719              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
 720                      &session->peer_cookie[0])) ||
 721             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 722             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 723             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 724 #ifdef CONFIG_XFRM
 725             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
 726              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 727 #endif
 728             (session->reorder_timeout &&
 729              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
 730                 goto nla_put_failure;
 731
 732         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 733         if (nest == NULL)
 734                 goto nla_put_failure;
 735
 736         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 737                 atomic_long_read(&session->stats.tx_packets)) ||
 738             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 739                 atomic_long_read(&session->stats.tx_bytes)) ||
 740             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 741                 atomic_long_read(&session->stats.tx_errors)) ||
 742             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 743                 atomic_long_read(&session->stats.rx_packets)) ||
 744             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 745                 atomic_long_read(&session->stats.rx_bytes)) ||
 746             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 747                 atomic_long_read(&session->stats.rx_seq_discards)) ||
 748             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 749                 atomic_long_read(&session->stats.rx_oos_packets)) ||
 750             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 751                 atomic_long_read(&session->stats.rx_errors)))
 752                 goto nla_put_failure;
 753         nla_nest_end(skb, nest);
 754
 755         return genlmsg_end(skb, hdr);
 756
 757  nla_put_failure:
 758         genlmsg_cancel(skb, hdr);
 759         return -1;
 760 }
 761
 762 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 763 {
 764         struct l2tp_session *session;
 765         struct sk_buff *msg;
 766         int ret;
 767
 768         session = l2tp_nl_session_find(info);
 769         if (session == NULL) {
 770                 ret = -ENODEV;
 771                 goto out;
 772         }
 773
 774         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 775         if (!msg) {
 776                 ret = -ENOMEM;
 777                 goto out;
 778         }
 779
 780         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 781                                    0, session, L2TP_CMD_SESSION_GET);
 782         if (ret < 0)
 783                 goto err_out;
 784
 785         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 786
 787 err_out:
 788         nlmsg_free(msg);
 789
 790 out:
 791         return ret;
 792 }
 793
 794 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 795 {
 796         struct net *net = sock_net(skb->sk);
 797         struct l2tp_session *session;
 798         struct l2tp_tunnel *tunnel = NULL;
 799         int ti = cb->args[0];
 800         int si = cb->args[1];
 801
 802         for (;;) {
 803                 if (tunnel == NULL) {
 804                         tunnel = l2tp_tunnel_find_nth(net, ti);
 805                         if (tunnel == NULL)
 806                                 goto out;
 807                 }
 808
 809                 session = l2tp_session_find_nth(tunnel, si);
 810                 if (session == NULL) {
 811                         ti++;
 812                         tunnel = NULL;
 813                         si = 0;
 814                         continue;
 815                 }
 816
 817                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 818                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 819                                          session, L2TP_CMD_SESSION_GET) <= 0)
 820                         break;
 821
 822                 si++;
 823         }
 824
 825 out:
 826         cb->args[0] = ti;
 827         cb->args[1] = si;
 828
 829         return skb->len;
 830 }
 831
 832 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 833         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 834         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 835         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 836         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 837         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 838         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 839         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 840         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 841         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 842         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 843         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 844         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 845         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 846         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 847         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 848         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 849         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 850         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 851         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 852         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 853         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 854         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 855         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 856         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 857         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 858         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 859         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 860         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 861         [L2TP_ATTR_IP6_SADDR] = {
 862                 .type = NLA_BINARY,
 863                 .len = sizeof(struct in6_addr),
 864         },
 865         [L2TP_ATTR_IP6_DADDR] = {
 866                 .type = NLA_BINARY,
 867                 .len = sizeof(struct in6_addr),
 868         },
 869         [L2TP_ATTR_IFNAME] = {
 870                 .type = NLA_NUL_STRING,
 871                 .len = IFNAMSIZ - 1,
 872         },
 873         [L2TP_ATTR_COOKIE] = {
 874                 .type = NLA_BINARY,
 875                 .len = 8,
 876         },
 877         [L2TP_ATTR_PEER_COOKIE] = {
 878                 .type = NLA_BINARY,
 879                 .len = 8,
 880         },
 881 };
 882
 883 static const struct genl_ops l2tp_nl_ops[] = {
 884         {
 885                 .cmd = L2TP_CMD_NOOP,
 886                 .doit = l2tp_nl_cmd_noop,
 887                 .policy = l2tp_nl_policy,
 888                 /* can be retrieved by unprivileged users */
 889         },
 890         {
 891                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 892                 .doit = l2tp_nl_cmd_tunnel_create,
 893                 .policy = l2tp_nl_policy,
 894                 .flags = GENL_ADMIN_PERM,
 895         },
 896         {
 897                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 898                 .doit = l2tp_nl_cmd_tunnel_delete,
 899                 .policy = l2tp_nl_policy,
 900                 .flags = GENL_ADMIN_PERM,
 901         },
 902         {
 903                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 904                 .doit = l2tp_nl_cmd_tunnel_modify,
 905                 .policy = l2tp_nl_policy,
 906                 .flags = GENL_ADMIN_PERM,
 907         },
 908         {
 909                 .cmd = L2TP_CMD_TUNNEL_GET,
 910                 .doit = l2tp_nl_cmd_tunnel_get,
 911                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 912                 .policy = l2tp_nl_policy,
 913                 .flags = GENL_ADMIN_PERM,
 914         },
 915         {
 916                 .cmd = L2TP_CMD_SESSION_CREATE,
 917                 .doit = l2tp_nl_cmd_session_create,
 918                 .policy = l2tp_nl_policy,
 919                 .flags = GENL_ADMIN_PERM,
 920         },
 921         {
 922                 .cmd = L2TP_CMD_SESSION_DELETE,
 923                 .doit = l2tp_nl_cmd_session_delete,
 924                 .policy = l2tp_nl_policy,
 925                 .flags = GENL_ADMIN_PERM,
 926         },
 927         {
 928                 .cmd = L2TP_CMD_SESSION_MODIFY,
 929                 .doit = l2tp_nl_cmd_session_modify,
 930                 .policy = l2tp_nl_policy,
 931                 .flags = GENL_ADMIN_PERM,
 932         },
 933         {
 934                 .cmd = L2TP_CMD_SESSION_GET,
 935                 .doit = l2tp_nl_cmd_session_get,
 936                 .dumpit = l2tp_nl_cmd_session_dump,
 937                 .policy = l2tp_nl_policy,
 938                 .flags = GENL_ADMIN_PERM,
 939         },
 940 };
 941
 942 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 943 {
 944         int ret;
 945
 946         ret = -EINVAL;
 947         if (pw_type >= __L2TP_PWTYPE_MAX)
 948                 goto err;
 949
 950         genl_lock();
 951         ret = -EBUSY;
 952         if (l2tp_nl_cmd_ops[pw_type])
 953                 goto out;
 954
 955         l2tp_nl_cmd_ops[pw_type] = ops;
 956         ret = 0;
 957
 958 out:
 959         genl_unlock();
 960 err:
 961         return ret;
 962 }
 963 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 964
 965 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 966 {
 967         if (pw_type < __L2TP_PWTYPE_MAX) {
 968                 genl_lock();
 969                 l2tp_nl_cmd_ops[pw_type] = NULL;
 970                 genl_unlock();
 971         }
 972 }
 973 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 974
 975 static int l2tp_nl_init(void)
 976 {
 977         pr_info("L2TP netlink interface\n");
 978         return genl_register_family_with_ops_groups(&l2tp_nl_family,
 979                                                     l2tp_nl_ops,
 980                                                     l2tp_multicast_group);
 981 }
 982
 983 static void l2tp_nl_cleanup(void)
 984 {
 985         genl_unregister_family(&l2tp_nl_family);
 986 }
 987
 988 module_init(l2tp_nl_init);
 989 module_exit(l2tp_nl_cleanup);
 990
 991 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 992 MODULE_DESCRIPTION("L2TP netlink");
 993 MODULE_LICENSE("GPL");
 994 MODULE_VERSION("1.0");
 995 MODULE_ALIAS_GENL_FAMILY("l2tp");