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                 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_in_addr(
 209                                 info->attrs[L2TP_ATTR_IP_SADDR]);
 210                         cfg.peer_ip.s_addr = nla_get_in_addr(
 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_in6_addr(skb, L2TP_ATTR_IP6_SADDR,
 380                                              &np->saddr) ||
 381                             nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR,
 382                                              &sk->sk_v6_daddr))
 383                                 goto nla_put_failure;
 384                 } else
 385 #endif
 386                 if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR,
 387                                     inet->inet_saddr) ||
 388                     nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR,
 389                                     inet->inet_daddr))
 390                         goto nla_put_failure;
 391                 break;
 392         }
 393
 394 out:
 395         genlmsg_end(skb, hdr);
 396         return 0;
 397
 398 nla_put_failure:
 399         genlmsg_cancel(skb, hdr);
 400         return -1;
 401 }
 402
 403 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 404 {
 405         struct l2tp_tunnel *tunnel;
 406         struct sk_buff *msg;
 407         u32 tunnel_id;
 408         int ret = -ENOBUFS;
 409         struct net *net = genl_info_net(info);
 410
 411         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 412                 ret = -EINVAL;
 413                 goto out;
 414         }
 415
 416         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 417
 418         tunnel = l2tp_tunnel_find(net, tunnel_id);
 419         if (tunnel == NULL) {
 420                 ret = -ENODEV;
 421                 goto out;
 422         }
 423
 424         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 425         if (!msg) {
 426                 ret = -ENOMEM;
 427                 goto out;
 428         }
 429
 430         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 431                                   NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
 432         if (ret < 0)
 433                 goto err_out;
 434
 435         return genlmsg_unicast(net, msg, info->snd_portid);
 436
 437 err_out:
 438         nlmsg_free(msg);
 439
 440 out:
 441         return ret;
 442 }
 443
 444 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 445 {
 446         int ti = cb->args[0];
 447         struct l2tp_tunnel *tunnel;
 448         struct net *net = sock_net(skb->sk);
 449
 450         for (;;) {
 451                 tunnel = l2tp_tunnel_find_nth(net, ti);
 452                 if (tunnel == NULL)
 453                         goto out;
 454
 455                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 456                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 457                                         tunnel, L2TP_CMD_TUNNEL_GET) < 0)
 458                         goto out;
 459
 460                 ti++;
 461         }
 462
 463 out:
 464         cb->args[0] = ti;
 465
 466         return skb->len;
 467 }
 468
 469 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 470 {
 471         u32 tunnel_id = 0;
 472         u32 session_id;
 473         u32 peer_session_id;
 474         int ret = 0;
 475         struct l2tp_tunnel *tunnel;
 476         struct l2tp_session *session;
 477         struct l2tp_session_cfg cfg = { 0, };
 478         struct net *net = genl_info_net(info);
 479
 480         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 481                 ret = -EINVAL;
 482                 goto out;
 483         }
 484         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 485         tunnel = l2tp_tunnel_find(net, tunnel_id);
 486         if (!tunnel) {
 487                 ret = -ENODEV;
 488                 goto out;
 489         }
 490
 491         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 492                 ret = -EINVAL;
 493                 goto out;
 494         }
 495         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 496         session = l2tp_session_find(net, tunnel, session_id);
 497         if (session) {
 498                 ret = -EEXIST;
 499                 goto out;
 500         }
 501
 502         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 503                 ret = -EINVAL;
 504                 goto out;
 505         }
 506         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 507
 508         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 509                 ret = -EINVAL;
 510                 goto out;
 511         }
 512         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 513         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 514                 ret = -EINVAL;
 515                 goto out;
 516         }
 517
 518         if (tunnel->version > 2) {
 519                 if (info->attrs[L2TP_ATTR_OFFSET])
 520                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 521
 522                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 523                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 524
 525                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 526                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 527                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 528
 529                 cfg.l2specific_len = 4;
 530                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 531                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 532
 533                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 534                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 535                         if (len > 8) {
 536                                 ret = -EINVAL;
 537                                 goto out;
 538                         }
 539                         cfg.cookie_len = len;
 540                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 541                 }
 542                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 543                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 544                         if (len > 8) {
 545                                 ret = -EINVAL;
 546                                 goto out;
 547                         }
 548                         cfg.peer_cookie_len = len;
 549                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 550                 }
 551                 if (info->attrs[L2TP_ATTR_IFNAME])
 552                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 553
 554                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 555                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 556         }
 557
 558         if (info->attrs[L2TP_ATTR_DEBUG])
 559                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 560
 561         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 562                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 563
 564         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 565                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 566
 567         if (info->attrs[L2TP_ATTR_LNS_MODE])
 568                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 569
 570         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 571                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 572
 573         if (info->attrs[L2TP_ATTR_MTU])
 574                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 575
 576         if (info->attrs[L2TP_ATTR_MRU])
 577                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 578
 579         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 580             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 581                 ret = -EPROTONOSUPPORT;
 582                 goto out;
 583         }
 584
 585         /* Check that pseudowire-specific params are present */
 586         switch (cfg.pw_type) {
 587         case L2TP_PWTYPE_NONE:
 588                 break;
 589         case L2TP_PWTYPE_ETH_VLAN:
 590                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 591                         ret = -EINVAL;
 592                         goto out;
 593                 }
 594                 break;
 595         case L2TP_PWTYPE_ETH:
 596                 break;
 597         case L2TP_PWTYPE_PPP:
 598         case L2TP_PWTYPE_PPP_AC:
 599                 break;
 600         case L2TP_PWTYPE_IP:
 601         default:
 602                 ret = -EPROTONOSUPPORT;
 603                 break;
 604         }
 605
 606         ret = -EPROTONOSUPPORT;
 607         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 608                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 609                         session_id, peer_session_id, &cfg);
 610
 611         if (ret >= 0) {
 612                 session = l2tp_session_find(net, tunnel, session_id);
 613                 if (session)
 614                         ret = l2tp_session_notify(&l2tp_nl_family, info, session,
 615                                                   L2TP_CMD_SESSION_CREATE);
 616         }
 617
 618 out:
 619         return ret;
 620 }
 621
 622 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 623 {
 624         int ret = 0;
 625         struct l2tp_session *session;
 626         u16 pw_type;
 627
 628         session = l2tp_nl_session_find(info);
 629         if (session == NULL) {
 630                 ret = -ENODEV;
 631                 goto out;
 632         }
 633
 634         l2tp_session_notify(&l2tp_nl_family, info,
 635                             session, L2TP_CMD_SESSION_DELETE);
 636
 637         pw_type = session->pwtype;
 638         if (pw_type < __L2TP_PWTYPE_MAX)
 639                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 640                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 641
 642 out:
 643         return ret;
 644 }
 645
 646 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 647 {
 648         int ret = 0;
 649         struct l2tp_session *session;
 650
 651         session = l2tp_nl_session_find(info);
 652         if (session == NULL) {
 653                 ret = -ENODEV;
 654                 goto out;
 655         }
 656
 657         if (info->attrs[L2TP_ATTR_DEBUG])
 658                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 659
 660         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 661                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 662
 663         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 664                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 665
 666         if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 667                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 668                 l2tp_session_set_header_len(session, session->tunnel->version);
 669         }
 670
 671         if (info->attrs[L2TP_ATTR_LNS_MODE])
 672                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 673
 674         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 675                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 676
 677         if (info->attrs[L2TP_ATTR_MTU])
 678                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 679
 680         if (info->attrs[L2TP_ATTR_MRU])
 681                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 682
 683         ret = l2tp_session_notify(&l2tp_nl_family, info,
 684                                   session, L2TP_CMD_SESSION_MODIFY);
 685
 686 out:
 687         return ret;
 688 }
 689
 690 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 691                                 struct l2tp_session *session, u8 cmd)
 692 {
 693         void *hdr;
 694         struct nlattr *nest;
 695         struct l2tp_tunnel *tunnel = session->tunnel;
 696         struct sock *sk = NULL;
 697
 698         sk = tunnel->sock;
 699
 700         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 701         if (!hdr)
 702                 return -EMSGSIZE;
 703
 704         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 705             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 706             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 707             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
 708                         session->peer_session_id) ||
 709             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 710             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
 711             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
 712             (session->mru &&
 713              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
 714                 goto nla_put_failure;
 715
 716         if ((session->ifname[0] &&
 717              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 718             (session->cookie_len &&
 719              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
 720                      &session->cookie[0])) ||
 721             (session->peer_cookie_len &&
 722              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
 723                      &session->peer_cookie[0])) ||
 724             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 725             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 726             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 727 #ifdef CONFIG_XFRM
 728             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
 729              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 730 #endif
 731             (session->reorder_timeout &&
 732              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
 733                 goto nla_put_failure;
 734
 735         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 736         if (nest == NULL)
 737                 goto nla_put_failure;
 738
 739         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 740                 atomic_long_read(&session->stats.tx_packets)) ||
 741             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 742                 atomic_long_read(&session->stats.tx_bytes)) ||
 743             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 744                 atomic_long_read(&session->stats.tx_errors)) ||
 745             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 746                 atomic_long_read(&session->stats.rx_packets)) ||
 747             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 748                 atomic_long_read(&session->stats.rx_bytes)) ||
 749             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 750                 atomic_long_read(&session->stats.rx_seq_discards)) ||
 751             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 752                 atomic_long_read(&session->stats.rx_oos_packets)) ||
 753             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 754                 atomic_long_read(&session->stats.rx_errors)))
 755                 goto nla_put_failure;
 756         nla_nest_end(skb, nest);
 757
 758         genlmsg_end(skb, hdr);
 759         return 0;
 760
 761  nla_put_failure:
 762         genlmsg_cancel(skb, hdr);
 763         return -1;
 764 }
 765
 766 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 767 {
 768         struct l2tp_session *session;
 769         struct sk_buff *msg;
 770         int ret;
 771
 772         session = l2tp_nl_session_find(info);
 773         if (session == NULL) {
 774                 ret = -ENODEV;
 775                 goto out;
 776         }
 777
 778         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 779         if (!msg) {
 780                 ret = -ENOMEM;
 781                 goto out;
 782         }
 783
 784         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 785                                    0, session, L2TP_CMD_SESSION_GET);
 786         if (ret < 0)
 787                 goto err_out;
 788
 789         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 790
 791 err_out:
 792         nlmsg_free(msg);
 793
 794 out:
 795         return ret;
 796 }
 797
 798 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 799 {
 800         struct net *net = sock_net(skb->sk);
 801         struct l2tp_session *session;
 802         struct l2tp_tunnel *tunnel = NULL;
 803         int ti = cb->args[0];
 804         int si = cb->args[1];
 805
 806         for (;;) {
 807                 if (tunnel == NULL) {
 808                         tunnel = l2tp_tunnel_find_nth(net, ti);
 809                         if (tunnel == NULL)
 810                                 goto out;
 811                 }
 812
 813                 session = l2tp_session_find_nth(tunnel, si);
 814                 if (session == NULL) {
 815                         ti++;
 816                         tunnel = NULL;
 817                         si = 0;
 818                         continue;
 819                 }
 820
 821                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 822                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 823                                          session, L2TP_CMD_SESSION_GET) < 0)
 824                         break;
 825
 826                 si++;
 827         }
 828
 829 out:
 830         cb->args[0] = ti;
 831         cb->args[1] = si;
 832
 833         return skb->len;
 834 }
 835
 836 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 837         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 838         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 839         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 840         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 841         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 842         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 843         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 844         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 845         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 846         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 847         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 848         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 849         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 850         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 851         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 852         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 853         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 854         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 855         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 856         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 857         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 858         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 859         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 860         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 861         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 862         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 863         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 864         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 865         [L2TP_ATTR_IP6_SADDR] = {
 866                 .type = NLA_BINARY,
 867                 .len = sizeof(struct in6_addr),
 868         },
 869         [L2TP_ATTR_IP6_DADDR] = {
 870                 .type = NLA_BINARY,
 871                 .len = sizeof(struct in6_addr),
 872         },
 873         [L2TP_ATTR_IFNAME] = {
 874                 .type = NLA_NUL_STRING,
 875                 .len = IFNAMSIZ - 1,
 876         },
 877         [L2TP_ATTR_COOKIE] = {
 878                 .type = NLA_BINARY,
 879                 .len = 8,
 880         },
 881         [L2TP_ATTR_PEER_COOKIE] = {
 882                 .type = NLA_BINARY,
 883                 .len = 8,
 884         },
 885 };
 886
 887 static const struct genl_ops l2tp_nl_ops[] = {
 888         {
 889                 .cmd = L2TP_CMD_NOOP,
 890                 .doit = l2tp_nl_cmd_noop,
 891                 .policy = l2tp_nl_policy,
 892                 /* can be retrieved by unprivileged users */
 893         },
 894         {
 895                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 896                 .doit = l2tp_nl_cmd_tunnel_create,
 897                 .policy = l2tp_nl_policy,
 898                 .flags = GENL_ADMIN_PERM,
 899         },
 900         {
 901                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 902                 .doit = l2tp_nl_cmd_tunnel_delete,
 903                 .policy = l2tp_nl_policy,
 904                 .flags = GENL_ADMIN_PERM,
 905         },
 906         {
 907                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 908                 .doit = l2tp_nl_cmd_tunnel_modify,
 909                 .policy = l2tp_nl_policy,
 910                 .flags = GENL_ADMIN_PERM,
 911         },
 912         {
 913                 .cmd = L2TP_CMD_TUNNEL_GET,
 914                 .doit = l2tp_nl_cmd_tunnel_get,
 915                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 916                 .policy = l2tp_nl_policy,
 917                 .flags = GENL_ADMIN_PERM,
 918         },
 919         {
 920                 .cmd = L2TP_CMD_SESSION_CREATE,
 921                 .doit = l2tp_nl_cmd_session_create,
 922                 .policy = l2tp_nl_policy,
 923                 .flags = GENL_ADMIN_PERM,
 924         },
 925         {
 926                 .cmd = L2TP_CMD_SESSION_DELETE,
 927                 .doit = l2tp_nl_cmd_session_delete,
 928                 .policy = l2tp_nl_policy,
 929                 .flags = GENL_ADMIN_PERM,
 930         },
 931         {
 932                 .cmd = L2TP_CMD_SESSION_MODIFY,
 933                 .doit = l2tp_nl_cmd_session_modify,
 934                 .policy = l2tp_nl_policy,
 935                 .flags = GENL_ADMIN_PERM,
 936         },
 937         {
 938                 .cmd = L2TP_CMD_SESSION_GET,
 939                 .doit = l2tp_nl_cmd_session_get,
 940                 .dumpit = l2tp_nl_cmd_session_dump,
 941                 .policy = l2tp_nl_policy,
 942                 .flags = GENL_ADMIN_PERM,
 943         },
 944 };
 945
 946 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 947 {
 948         int ret;
 949
 950         ret = -EINVAL;
 951         if (pw_type >= __L2TP_PWTYPE_MAX)
 952                 goto err;
 953
 954         genl_lock();
 955         ret = -EBUSY;
 956         if (l2tp_nl_cmd_ops[pw_type])
 957                 goto out;
 958
 959         l2tp_nl_cmd_ops[pw_type] = ops;
 960         ret = 0;
 961
 962 out:
 963         genl_unlock();
 964 err:
 965         return ret;
 966 }
 967 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 968
 969 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 970 {
 971         if (pw_type < __L2TP_PWTYPE_MAX) {
 972                 genl_lock();
 973                 l2tp_nl_cmd_ops[pw_type] = NULL;
 974                 genl_unlock();
 975         }
 976 }
 977 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 978
 979 static int l2tp_nl_init(void)
 980 {
 981         pr_info("L2TP netlink interface\n");
 982         return genl_register_family_with_ops_groups(&l2tp_nl_family,
 983                                                     l2tp_nl_ops,
 984                                                     l2tp_multicast_group);
 985 }
 986
 987 static void l2tp_nl_cleanup(void)
 988 {
 989         genl_unregister_family(&l2tp_nl_family);
 990 }
 991
 992 module_init(l2tp_nl_init);
 993 module_exit(l2tp_nl_cleanup);
 994
 995 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 996 MODULE_DESCRIPTION("L2TP netlink");
 997 MODULE_LICENSE("GPL");
 998 MODULE_VERSION("1.0");
 999 MODULE_ALIAS_GENL_FAMILY("l2tp");