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         struct l2tp_stats stats;
 229         unsigned int start;
 230
 231         hdr = genlmsg_put(skb, pid, seq, &l2tp_nl_family, flags,
 232                           L2TP_CMD_TUNNEL_GET);
 233         if (IS_ERR(hdr))
 234                 return PTR_ERR(hdr);
 235
 236         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 237             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 238             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 239             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
 240             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 241                 goto nla_put_failure;
 242
 243         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 244         if (nest == NULL)
 245                 goto nla_put_failure;
 246
 247         do {
 248                 start = u64_stats_fetch_begin(&tunnel->stats.syncp);
 249                 stats.tx_packets = tunnel->stats.tx_packets;
 250                 stats.tx_bytes = tunnel->stats.tx_bytes;
 251                 stats.tx_errors = tunnel->stats.tx_errors;
 252                 stats.rx_packets = tunnel->stats.rx_packets;
 253                 stats.rx_bytes = tunnel->stats.rx_bytes;
 254                 stats.rx_errors = tunnel->stats.rx_errors;
 255                 stats.rx_seq_discards = tunnel->stats.rx_seq_discards;
 256                 stats.rx_oos_packets = tunnel->stats.rx_oos_packets;
 257         } while (u64_stats_fetch_retry(&tunnel->stats.syncp, start));
 258
 259         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
 260             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
 261             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
 262             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
 263             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
 264             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 265                         stats.rx_seq_discards) ||
 266             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 267                         stats.rx_oos_packets) ||
 268             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
 269                 goto nla_put_failure;
 270         nla_nest_end(skb, nest);
 271
 272         sk = tunnel->sock;
 273         if (!sk)
 274                 goto out;
 275
 276         inet = inet_sk(sk);
 277
 278         switch (tunnel->encap) {
 279         case L2TP_ENCAPTYPE_UDP:
 280                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 281                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
 282                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM,
 283                                (sk->sk_no_check != UDP_CSUM_NOXMIT)))
 284                         goto nla_put_failure;
 285                 /* NOBREAK */
 286         case L2TP_ENCAPTYPE_IP:
 287                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 288                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 289                         goto nla_put_failure;
 290                 break;
 291         }
 292
 293 out:
 294         return genlmsg_end(skb, hdr);
 295
 296 nla_put_failure:
 297         genlmsg_cancel(skb, hdr);
 298         return -1;
 299 }
 300
 301 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 302 {
 303         struct l2tp_tunnel *tunnel;
 304         struct sk_buff *msg;
 305         u32 tunnel_id;
 306         int ret = -ENOBUFS;
 307         struct net *net = genl_info_net(info);
 308
 309         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 310                 ret = -EINVAL;
 311                 goto out;
 312         }
 313
 314         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 315
 316         tunnel = l2tp_tunnel_find(net, tunnel_id);
 317         if (tunnel == NULL) {
 318                 ret = -ENODEV;
 319                 goto out;
 320         }
 321
 322         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 323         if (!msg) {
 324                 ret = -ENOMEM;
 325                 goto out;
 326         }
 327
 328         ret = l2tp_nl_tunnel_send(msg, info->snd_pid, info->snd_seq,
 329                                   NLM_F_ACK, tunnel);
 330         if (ret < 0)
 331                 goto err_out;
 332
 333         return genlmsg_unicast(net, msg, info->snd_pid);
 334
 335 err_out:
 336         nlmsg_free(msg);
 337
 338 out:
 339         return ret;
 340 }
 341
 342 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 343 {
 344         int ti = cb->args[0];
 345         struct l2tp_tunnel *tunnel;
 346         struct net *net = sock_net(skb->sk);
 347
 348         for (;;) {
 349                 tunnel = l2tp_tunnel_find_nth(net, ti);
 350                 if (tunnel == NULL)
 351                         goto out;
 352
 353                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).pid,
 354                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 355                                         tunnel) <= 0)
 356                         goto out;
 357
 358                 ti++;
 359         }
 360
 361 out:
 362         cb->args[0] = ti;
 363
 364         return skb->len;
 365 }
 366
 367 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 368 {
 369         u32 tunnel_id = 0;
 370         u32 session_id;
 371         u32 peer_session_id;
 372         int ret = 0;
 373         struct l2tp_tunnel *tunnel;
 374         struct l2tp_session *session;
 375         struct l2tp_session_cfg cfg = { 0, };
 376         struct net *net = genl_info_net(info);
 377
 378         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 379                 ret = -EINVAL;
 380                 goto out;
 381         }
 382         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 383         tunnel = l2tp_tunnel_find(net, tunnel_id);
 384         if (!tunnel) {
 385                 ret = -ENODEV;
 386                 goto out;
 387         }
 388
 389         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 390                 ret = -EINVAL;
 391                 goto out;
 392         }
 393         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 394         session = l2tp_session_find(net, tunnel, session_id);
 395         if (session) {
 396                 ret = -EEXIST;
 397                 goto out;
 398         }
 399
 400         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 401                 ret = -EINVAL;
 402                 goto out;
 403         }
 404         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 405
 406         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 407                 ret = -EINVAL;
 408                 goto out;
 409         }
 410         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 411         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 412                 ret = -EINVAL;
 413                 goto out;
 414         }
 415
 416         if (tunnel->version > 2) {
 417                 if (info->attrs[L2TP_ATTR_OFFSET])
 418                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 419
 420                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 421                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 422
 423                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 424                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 425                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 426
 427                 cfg.l2specific_len = 4;
 428                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 429                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 430
 431                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 432                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 433                         if (len > 8) {
 434                                 ret = -EINVAL;
 435                                 goto out;
 436                         }
 437                         cfg.cookie_len = len;
 438                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 439                 }
 440                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 441                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 442                         if (len > 8) {
 443                                 ret = -EINVAL;
 444                                 goto out;
 445                         }
 446                         cfg.peer_cookie_len = len;
 447                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 448                 }
 449                 if (info->attrs[L2TP_ATTR_IFNAME])
 450                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 451
 452                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 453                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 454         }
 455
 456         if (info->attrs[L2TP_ATTR_DEBUG])
 457                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 458
 459         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 460                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 461
 462         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 463                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 464
 465         if (info->attrs[L2TP_ATTR_LNS_MODE])
 466                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 467
 468         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 469                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 470
 471         if (info->attrs[L2TP_ATTR_MTU])
 472                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 473
 474         if (info->attrs[L2TP_ATTR_MRU])
 475                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 476
 477         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 478             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 479                 ret = -EPROTONOSUPPORT;
 480                 goto out;
 481         }
 482
 483         /* Check that pseudowire-specific params are present */
 484         switch (cfg.pw_type) {
 485         case L2TP_PWTYPE_NONE:
 486                 break;
 487         case L2TP_PWTYPE_ETH_VLAN:
 488                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 489                         ret = -EINVAL;
 490                         goto out;
 491                 }
 492                 break;
 493         case L2TP_PWTYPE_ETH:
 494                 break;
 495         case L2TP_PWTYPE_PPP:
 496         case L2TP_PWTYPE_PPP_AC:
 497                 break;
 498         case L2TP_PWTYPE_IP:
 499         default:
 500                 ret = -EPROTONOSUPPORT;
 501                 break;
 502         }
 503
 504         ret = -EPROTONOSUPPORT;
 505         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 506                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 507                         session_id, peer_session_id, &cfg);
 508
 509 out:
 510         return ret;
 511 }
 512
 513 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 514 {
 515         int ret = 0;
 516         struct l2tp_session *session;
 517         u16 pw_type;
 518
 519         session = l2tp_nl_session_find(info);
 520         if (session == NULL) {
 521                 ret = -ENODEV;
 522                 goto out;
 523         }
 524
 525         pw_type = session->pwtype;
 526         if (pw_type < __L2TP_PWTYPE_MAX)
 527                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 528                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 529
 530 out:
 531         return ret;
 532 }
 533
 534 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 535 {
 536         int ret = 0;
 537         struct l2tp_session *session;
 538
 539         session = l2tp_nl_session_find(info);
 540         if (session == NULL) {
 541                 ret = -ENODEV;
 542                 goto out;
 543         }
 544
 545         if (info->attrs[L2TP_ATTR_DEBUG])
 546                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 547
 548         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 549                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 550
 551         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 552                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 553
 554         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 555                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 556
 557         if (info->attrs[L2TP_ATTR_LNS_MODE])
 558                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 559
 560         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 561                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 562
 563         if (info->attrs[L2TP_ATTR_MTU])
 564                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 565
 566         if (info->attrs[L2TP_ATTR_MRU])
 567                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 568
 569 out:
 570         return ret;
 571 }
 572
 573 static int l2tp_nl_session_send(struct sk_buff *skb, u32 pid, u32 seq, int flags,
 574                                 struct l2tp_session *session)
 575 {
 576         void *hdr;
 577         struct nlattr *nest;
 578         struct l2tp_tunnel *tunnel = session->tunnel;
 579         struct sock *sk = NULL;
 580         struct l2tp_stats stats;
 581         unsigned int start;
 582
 583         sk = tunnel->sock;
 584
 585         hdr = genlmsg_put(skb, pid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
 586         if (IS_ERR(hdr))
 587                 return PTR_ERR(hdr);
 588
 589         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 590             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 591             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 592             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
 593                         session->peer_session_id) ||
 594             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 595             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
 596             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
 597             (session->mru &&
 598              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
 599                 goto nla_put_failure;
 600
 601         if ((session->ifname && session->ifname[0] &&
 602              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 603             (session->cookie_len &&
 604              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
 605                      &session->cookie[0])) ||
 606             (session->peer_cookie_len &&
 607              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
 608                      &session->peer_cookie[0])) ||
 609             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 610             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 611             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 612 #ifdef CONFIG_XFRM
 613             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
 614              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 615 #endif
 616             (session->reorder_timeout &&
 617              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
 618                 goto nla_put_failure;
 619
 620         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 621         if (nest == NULL)
 622                 goto nla_put_failure;
 623
 624         do {
 625                 start = u64_stats_fetch_begin(&session->stats.syncp);
 626                 stats.tx_packets = session->stats.tx_packets;
 627                 stats.tx_bytes = session->stats.tx_bytes;
 628                 stats.tx_errors = session->stats.tx_errors;
 629                 stats.rx_packets = session->stats.rx_packets;
 630                 stats.rx_bytes = session->stats.rx_bytes;
 631                 stats.rx_errors = session->stats.rx_errors;
 632                 stats.rx_seq_discards = session->stats.rx_seq_discards;
 633                 stats.rx_oos_packets = session->stats.rx_oos_packets;
 634         } while (u64_stats_fetch_retry(&session->stats.syncp, start));
 635
 636         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
 637             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
 638             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
 639             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
 640             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
 641             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 642                         stats.rx_seq_discards) ||
 643             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 644                         stats.rx_oos_packets) ||
 645             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
 646                 goto nla_put_failure;
 647         nla_nest_end(skb, nest);
 648
 649         return genlmsg_end(skb, hdr);
 650
 651  nla_put_failure:
 652         genlmsg_cancel(skb, hdr);
 653         return -1;
 654 }
 655
 656 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 657 {
 658         struct l2tp_session *session;
 659         struct sk_buff *msg;
 660         int ret;
 661
 662         session = l2tp_nl_session_find(info);
 663         if (session == NULL) {
 664                 ret = -ENODEV;
 665                 goto out;
 666         }
 667
 668         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 669         if (!msg) {
 670                 ret = -ENOMEM;
 671                 goto out;
 672         }
 673
 674         ret = l2tp_nl_session_send(msg, info->snd_pid, info->snd_seq,
 675                                    0, session);
 676         if (ret < 0)
 677                 goto err_out;
 678
 679         return genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
 680
 681 err_out:
 682         nlmsg_free(msg);
 683
 684 out:
 685         return ret;
 686 }
 687
 688 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 689 {
 690         struct net *net = sock_net(skb->sk);
 691         struct l2tp_session *session;
 692         struct l2tp_tunnel *tunnel = NULL;
 693         int ti = cb->args[0];
 694         int si = cb->args[1];
 695
 696         for (;;) {
 697                 if (tunnel == NULL) {
 698                         tunnel = l2tp_tunnel_find_nth(net, ti);
 699                         if (tunnel == NULL)
 700                                 goto out;
 701                 }
 702
 703                 session = l2tp_session_find_nth(tunnel, si);
 704                 if (session == NULL) {
 705                         ti++;
 706                         tunnel = NULL;
 707                         si = 0;
 708                         continue;
 709                 }
 710
 711                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).pid,
 712                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 713                                          session) <= 0)
 714                         break;
 715
 716                 si++;
 717         }
 718
 719 out:
 720         cb->args[0] = ti;
 721         cb->args[1] = si;
 722
 723         return skb->len;
 724 }
 725
 726 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 727         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 728         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 729         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 730         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 731         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 732         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 733         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 734         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 735         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 736         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 737         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 738         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 739         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 740         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 741         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 742         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 743         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 744         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 745         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 746         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 747         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 748         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 749         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 750         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 751         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 752         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 753         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 754         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 755         [L2TP_ATTR_IFNAME] = {
 756                 .type = NLA_NUL_STRING,
 757                 .len = IFNAMSIZ - 1,
 758         },
 759         [L2TP_ATTR_COOKIE] = {
 760                 .type = NLA_BINARY,
 761                 .len = 8,
 762         },
 763         [L2TP_ATTR_PEER_COOKIE] = {
 764                 .type = NLA_BINARY,
 765                 .len = 8,
 766         },
 767 };
 768
 769 static struct genl_ops l2tp_nl_ops[] = {
 770         {
 771                 .cmd = L2TP_CMD_NOOP,
 772                 .doit = l2tp_nl_cmd_noop,
 773                 .policy = l2tp_nl_policy,
 774                 /* can be retrieved by unprivileged users */
 775         },
 776         {
 777                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 778                 .doit = l2tp_nl_cmd_tunnel_create,
 779                 .policy = l2tp_nl_policy,
 780                 .flags = GENL_ADMIN_PERM,
 781         },
 782         {
 783                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 784                 .doit = l2tp_nl_cmd_tunnel_delete,
 785                 .policy = l2tp_nl_policy,
 786                 .flags = GENL_ADMIN_PERM,
 787         },
 788         {
 789                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 790                 .doit = l2tp_nl_cmd_tunnel_modify,
 791                 .policy = l2tp_nl_policy,
 792                 .flags = GENL_ADMIN_PERM,
 793         },
 794         {
 795                 .cmd = L2TP_CMD_TUNNEL_GET,
 796                 .doit = l2tp_nl_cmd_tunnel_get,
 797                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 798                 .policy = l2tp_nl_policy,
 799                 .flags = GENL_ADMIN_PERM,
 800         },
 801         {
 802                 .cmd = L2TP_CMD_SESSION_CREATE,
 803                 .doit = l2tp_nl_cmd_session_create,
 804                 .policy = l2tp_nl_policy,
 805                 .flags = GENL_ADMIN_PERM,
 806         },
 807         {
 808                 .cmd = L2TP_CMD_SESSION_DELETE,
 809                 .doit = l2tp_nl_cmd_session_delete,
 810                 .policy = l2tp_nl_policy,
 811                 .flags = GENL_ADMIN_PERM,
 812         },
 813         {
 814                 .cmd = L2TP_CMD_SESSION_MODIFY,
 815                 .doit = l2tp_nl_cmd_session_modify,
 816                 .policy = l2tp_nl_policy,
 817                 .flags = GENL_ADMIN_PERM,
 818         },
 819         {
 820                 .cmd = L2TP_CMD_SESSION_GET,
 821                 .doit = l2tp_nl_cmd_session_get,
 822                 .dumpit = l2tp_nl_cmd_session_dump,
 823                 .policy = l2tp_nl_policy,
 824                 .flags = GENL_ADMIN_PERM,
 825         },
 826 };
 827
 828 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 829 {
 830         int ret;
 831
 832         ret = -EINVAL;
 833         if (pw_type >= __L2TP_PWTYPE_MAX)
 834                 goto err;
 835
 836         genl_lock();
 837         ret = -EBUSY;
 838         if (l2tp_nl_cmd_ops[pw_type])
 839                 goto out;
 840
 841         l2tp_nl_cmd_ops[pw_type] = ops;
 842         ret = 0;
 843
 844 out:
 845         genl_unlock();
 846 err:
 847         return ret;
 848 }
 849 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 850
 851 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 852 {
 853         if (pw_type < __L2TP_PWTYPE_MAX) {
 854                 genl_lock();
 855                 l2tp_nl_cmd_ops[pw_type] = NULL;
 856                 genl_unlock();
 857         }
 858 }
 859 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 860
 861 static int l2tp_nl_init(void)
 862 {
 863         int err;
 864
 865         printk(KERN_INFO "L2TP netlink interface\n");
 866         err = genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops,
 867                                             ARRAY_SIZE(l2tp_nl_ops));
 868
 869         return err;
 870 }
 871
 872 static void l2tp_nl_cleanup(void)
 873 {
 874         genl_unregister_family(&l2tp_nl_family);
 875 }
 876
 877 module_init(l2tp_nl_init);
 878 module_exit(l2tp_nl_cleanup);
 879
 880 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 881 MODULE_DESCRIPTION("L2TP netlink");
 882 MODULE_LICENSE("GPL");
 883 MODULE_VERSION("1.0");
 884 MODULE_ALIAS("net-pf-" __stringify(PF_NETLINK) "-proto-" \
 885              __stringify(NETLINK_GENERIC) "-type-" "l2tp");