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 /* Accessed under genl lock */
  44 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
  45
  46 static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info)
  47 {
  48         u32 tunnel_id;
  49         u32 session_id;
  50         char *ifname;
  51         struct l2tp_tunnel *tunnel;
  52         struct l2tp_session *session = NULL;
  53         struct net *net = genl_info_net(info);
  54
  55         if (info->attrs[L2TP_ATTR_IFNAME]) {
  56                 ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
  57                 session = l2tp_session_find_by_ifname(net, ifname);
  58         } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
  59                    (info->attrs[L2TP_ATTR_CONN_ID])) {
  60                 tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
  61                 session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
  62                 tunnel = l2tp_tunnel_find(net, tunnel_id);
  63                 if (tunnel)
  64                         session = l2tp_session_find(net, tunnel, session_id);
  65         }
  66
  67         return session;
  68 }
  69
  70 static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
  71 {
  72         struct sk_buff *msg;
  73         void *hdr;
  74         int ret = -ENOBUFS;
  75
  76         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  77         if (!msg) {
  78                 ret = -ENOMEM;
  79                 goto out;
  80         }
  81
  82         hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
  83                           &l2tp_nl_family, 0, L2TP_CMD_NOOP);
  84         if (!hdr) {
  85                 ret = -EMSGSIZE;
  86                 goto err_out;
  87         }
  88
  89         genlmsg_end(msg, hdr);
  90
  91         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
  92
  93 err_out:
  94         nlmsg_free(msg);
  95
  96 out:
  97         return ret;
  98 }
  99
 100 static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
 101 {
 102         u32 tunnel_id;
 103         u32 peer_tunnel_id;
 104         int proto_version;
 105         int fd;
 106         int ret = 0;
 107         struct l2tp_tunnel_cfg cfg = { 0, };
 108         struct l2tp_tunnel *tunnel;
 109         struct net *net = genl_info_net(info);
 110
 111         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 112                 ret = -EINVAL;
 113                 goto out;
 114         }
 115         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 116
 117         if (!info->attrs[L2TP_ATTR_PEER_CONN_ID]) {
 118                 ret = -EINVAL;
 119                 goto out;
 120         }
 121         peer_tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_CONN_ID]);
 122
 123         if (!info->attrs[L2TP_ATTR_PROTO_VERSION]) {
 124                 ret = -EINVAL;
 125                 goto out;
 126         }
 127         proto_version = nla_get_u8(info->attrs[L2TP_ATTR_PROTO_VERSION]);
 128
 129         if (!info->attrs[L2TP_ATTR_ENCAP_TYPE]) {
 130                 ret = -EINVAL;
 131                 goto out;
 132         }
 133         cfg.encap = nla_get_u16(info->attrs[L2TP_ATTR_ENCAP_TYPE]);
 134
 135         fd = -1;
 136         if (info->attrs[L2TP_ATTR_FD]) {
 137                 fd = nla_get_u32(info->attrs[L2TP_ATTR_FD]);
 138         } else {
 139 #if IS_ENABLED(CONFIG_IPV6)
 140                 if (info->attrs[L2TP_ATTR_IP6_SADDR] &&
 141                     info->attrs[L2TP_ATTR_IP6_DADDR]) {
 142                         cfg.local_ip6 = nla_data(
 143                                 info->attrs[L2TP_ATTR_IP6_SADDR]);
 144                         cfg.peer_ip6 = nla_data(
 145                                 info->attrs[L2TP_ATTR_IP6_DADDR]);
 146                 } else
 147 #endif
 148                 if (info->attrs[L2TP_ATTR_IP_SADDR] &&
 149                     info->attrs[L2TP_ATTR_IP_DADDR]) {
 150                         cfg.local_ip.s_addr = nla_get_be32(
 151                                 info->attrs[L2TP_ATTR_IP_SADDR]);
 152                         cfg.peer_ip.s_addr = nla_get_be32(
 153                                 info->attrs[L2TP_ATTR_IP_DADDR]);
 154                 } else {
 155                         ret = -EINVAL;
 156                         goto out;
 157                 }
 158                 if (info->attrs[L2TP_ATTR_UDP_SPORT])
 159                         cfg.local_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_SPORT]);
 160                 if (info->attrs[L2TP_ATTR_UDP_DPORT])
 161                         cfg.peer_udp_port = nla_get_u16(info->attrs[L2TP_ATTR_UDP_DPORT]);
 162                 if (info->attrs[L2TP_ATTR_UDP_CSUM])
 163                         cfg.use_udp_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_CSUM]);
 164
 165 #if IS_ENABLED(CONFIG_IPV6)
 166                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX])
 167                         cfg.udp6_zero_tx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
 168                 if (info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX])
 169                         cfg.udp6_zero_rx_checksums = nla_get_flag(info->attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
 170 #endif
 171         }
 172
 173         if (info->attrs[L2TP_ATTR_DEBUG])
 174                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 175
 176         tunnel = l2tp_tunnel_find(net, tunnel_id);
 177         if (tunnel != NULL) {
 178                 ret = -EEXIST;
 179                 goto out;
 180         }
 181
 182         ret = -EINVAL;
 183         switch (cfg.encap) {
 184         case L2TP_ENCAPTYPE_UDP:
 185         case L2TP_ENCAPTYPE_IP:
 186                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
 187                                          peer_tunnel_id, &cfg, &tunnel);
 188                 break;
 189         }
 190
 191 out:
 192         return ret;
 193 }
 194
 195 static int l2tp_nl_cmd_tunnel_delete(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         (void) l2tp_tunnel_delete(tunnel);
 215
 216 out:
 217         return ret;
 218 }
 219
 220 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 221 {
 222         struct l2tp_tunnel *tunnel;
 223         u32 tunnel_id;
 224         int ret = 0;
 225         struct net *net = genl_info_net(info);
 226
 227         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 228                 ret = -EINVAL;
 229                 goto out;
 230         }
 231         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 232
 233         tunnel = l2tp_tunnel_find(net, tunnel_id);
 234         if (tunnel == NULL) {
 235                 ret = -ENODEV;
 236                 goto out;
 237         }
 238
 239         if (info->attrs[L2TP_ATTR_DEBUG])
 240                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 241
 242 out:
 243         return ret;
 244 }
 245
 246 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 247                                struct l2tp_tunnel *tunnel)
 248 {
 249         void *hdr;
 250         struct nlattr *nest;
 251         struct sock *sk = NULL;
 252         struct inet_sock *inet;
 253 #if IS_ENABLED(CONFIG_IPV6)
 254         struct ipv6_pinfo *np = NULL;
 255 #endif
 256
 257         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags,
 258                           L2TP_CMD_TUNNEL_GET);
 259         if (!hdr)
 260                 return -EMSGSIZE;
 261
 262         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 263             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 264             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 265             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
 266             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 267                 goto nla_put_failure;
 268
 269         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 270         if (nest == NULL)
 271                 goto nla_put_failure;
 272
 273         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 274                     atomic_long_read(&tunnel->stats.tx_packets)) ||
 275             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 276                     atomic_long_read(&tunnel->stats.tx_bytes)) ||
 277             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 278                     atomic_long_read(&tunnel->stats.tx_errors)) ||
 279             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 280                     atomic_long_read(&tunnel->stats.rx_packets)) ||
 281             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 282                     atomic_long_read(&tunnel->stats.rx_bytes)) ||
 283             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 284                     atomic_long_read(&tunnel->stats.rx_seq_discards)) ||
 285             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 286                     atomic_long_read(&tunnel->stats.rx_oos_packets)) ||
 287             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 288                     atomic_long_read(&tunnel->stats.rx_errors)))
 289                 goto nla_put_failure;
 290         nla_nest_end(skb, nest);
 291
 292         sk = tunnel->sock;
 293         if (!sk)
 294                 goto out;
 295
 296 #if IS_ENABLED(CONFIG_IPV6)
 297         if (sk->sk_family == AF_INET6)
 298                 np = inet6_sk(sk);
 299 #endif
 300
 301         inet = inet_sk(sk);
 302
 303         switch (tunnel->encap) {
 304         case L2TP_ENCAPTYPE_UDP:
 305                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 306                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
 307                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx))
 308                         goto nla_put_failure;
 309                 /* NOBREAK */
 310         case L2TP_ENCAPTYPE_IP:
 311 #if IS_ENABLED(CONFIG_IPV6)
 312                 if (np) {
 313                         if (nla_put(skb, L2TP_ATTR_IP6_SADDR, sizeof(np->saddr),
 314                                     &np->saddr) ||
 315                             nla_put(skb, L2TP_ATTR_IP6_DADDR, sizeof(sk->sk_v6_daddr),
 316                                     &sk->sk_v6_daddr))
 317                                 goto nla_put_failure;
 318                 } else
 319 #endif
 320                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 321                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 322                         goto nla_put_failure;
 323                 break;
 324         }
 325
 326 out:
 327         return genlmsg_end(skb, hdr);
 328
 329 nla_put_failure:
 330         genlmsg_cancel(skb, hdr);
 331         return -1;
 332 }
 333
 334 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 335 {
 336         struct l2tp_tunnel *tunnel;
 337         struct sk_buff *msg;
 338         u32 tunnel_id;
 339         int ret = -ENOBUFS;
 340         struct net *net = genl_info_net(info);
 341
 342         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 343                 ret = -EINVAL;
 344                 goto out;
 345         }
 346
 347         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 348
 349         tunnel = l2tp_tunnel_find(net, tunnel_id);
 350         if (tunnel == NULL) {
 351                 ret = -ENODEV;
 352                 goto out;
 353         }
 354
 355         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 356         if (!msg) {
 357                 ret = -ENOMEM;
 358                 goto out;
 359         }
 360
 361         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 362                                   NLM_F_ACK, tunnel);
 363         if (ret < 0)
 364                 goto err_out;
 365
 366         return genlmsg_unicast(net, msg, info->snd_portid);
 367
 368 err_out:
 369         nlmsg_free(msg);
 370
 371 out:
 372         return ret;
 373 }
 374
 375 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 376 {
 377         int ti = cb->args[0];
 378         struct l2tp_tunnel *tunnel;
 379         struct net *net = sock_net(skb->sk);
 380
 381         for (;;) {
 382                 tunnel = l2tp_tunnel_find_nth(net, ti);
 383                 if (tunnel == NULL)
 384                         goto out;
 385
 386                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 387                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 388                                         tunnel) <= 0)
 389                         goto out;
 390
 391                 ti++;
 392         }
 393
 394 out:
 395         cb->args[0] = ti;
 396
 397         return skb->len;
 398 }
 399
 400 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 401 {
 402         u32 tunnel_id = 0;
 403         u32 session_id;
 404         u32 peer_session_id;
 405         int ret = 0;
 406         struct l2tp_tunnel *tunnel;
 407         struct l2tp_session *session;
 408         struct l2tp_session_cfg cfg = { 0, };
 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         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 416         tunnel = l2tp_tunnel_find(net, tunnel_id);
 417         if (!tunnel) {
 418                 ret = -ENODEV;
 419                 goto out;
 420         }
 421
 422         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 423                 ret = -EINVAL;
 424                 goto out;
 425         }
 426         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 427         session = l2tp_session_find(net, tunnel, session_id);
 428         if (session) {
 429                 ret = -EEXIST;
 430                 goto out;
 431         }
 432
 433         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 434                 ret = -EINVAL;
 435                 goto out;
 436         }
 437         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 438
 439         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 440                 ret = -EINVAL;
 441                 goto out;
 442         }
 443         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 444         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 445                 ret = -EINVAL;
 446                 goto out;
 447         }
 448
 449         if (tunnel->version > 2) {
 450                 if (info->attrs[L2TP_ATTR_OFFSET])
 451                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 452
 453                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 454                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 455
 456                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 457                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 458                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 459
 460                 cfg.l2specific_len = 4;
 461                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 462                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 463
 464                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 465                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 466                         if (len > 8) {
 467                                 ret = -EINVAL;
 468                                 goto out;
 469                         }
 470                         cfg.cookie_len = len;
 471                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 472                 }
 473                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 474                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 475                         if (len > 8) {
 476                                 ret = -EINVAL;
 477                                 goto out;
 478                         }
 479                         cfg.peer_cookie_len = len;
 480                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 481                 }
 482                 if (info->attrs[L2TP_ATTR_IFNAME])
 483                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 484
 485                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 486                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 487         }
 488
 489         if (info->attrs[L2TP_ATTR_DEBUG])
 490                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 491
 492         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 493                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 494
 495         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 496                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 497
 498         if (info->attrs[L2TP_ATTR_LNS_MODE])
 499                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 500
 501         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 502                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 503
 504         if (info->attrs[L2TP_ATTR_MTU])
 505                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 506
 507         if (info->attrs[L2TP_ATTR_MRU])
 508                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 509
 510         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 511             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 512                 ret = -EPROTONOSUPPORT;
 513                 goto out;
 514         }
 515
 516         /* Check that pseudowire-specific params are present */
 517         switch (cfg.pw_type) {
 518         case L2TP_PWTYPE_NONE:
 519                 break;
 520         case L2TP_PWTYPE_ETH_VLAN:
 521                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 522                         ret = -EINVAL;
 523                         goto out;
 524                 }
 525                 break;
 526         case L2TP_PWTYPE_ETH:
 527                 break;
 528         case L2TP_PWTYPE_PPP:
 529         case L2TP_PWTYPE_PPP_AC:
 530                 break;
 531         case L2TP_PWTYPE_IP:
 532         default:
 533                 ret = -EPROTONOSUPPORT;
 534                 break;
 535         }
 536
 537         ret = -EPROTONOSUPPORT;
 538         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 539                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 540                         session_id, peer_session_id, &cfg);
 541
 542 out:
 543         return ret;
 544 }
 545
 546 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 547 {
 548         int ret = 0;
 549         struct l2tp_session *session;
 550         u16 pw_type;
 551
 552         session = l2tp_nl_session_find(info);
 553         if (session == NULL) {
 554                 ret = -ENODEV;
 555                 goto out;
 556         }
 557
 558         pw_type = session->pwtype;
 559         if (pw_type < __L2TP_PWTYPE_MAX)
 560                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 561                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 562
 563 out:
 564         return ret;
 565 }
 566
 567 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 568 {
 569         int ret = 0;
 570         struct l2tp_session *session;
 571
 572         session = l2tp_nl_session_find(info);
 573         if (session == NULL) {
 574                 ret = -ENODEV;
 575                 goto out;
 576         }
 577
 578         if (info->attrs[L2TP_ATTR_DEBUG])
 579                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 580
 581         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 582                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 583
 584         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 585                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 586
 587         if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 588                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 589                 l2tp_session_set_header_len(session, session->tunnel->version);
 590         }
 591
 592         if (info->attrs[L2TP_ATTR_LNS_MODE])
 593                 session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 594
 595         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 596                 session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 597
 598         if (info->attrs[L2TP_ATTR_MTU])
 599                 session->mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 600
 601         if (info->attrs[L2TP_ATTR_MRU])
 602                 session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 603
 604 out:
 605         return ret;
 606 }
 607
 608 static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 609                                 struct l2tp_session *session)
 610 {
 611         void *hdr;
 612         struct nlattr *nest;
 613         struct l2tp_tunnel *tunnel = session->tunnel;
 614         struct sock *sk = NULL;
 615
 616         sk = tunnel->sock;
 617
 618         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
 619         if (!hdr)
 620                 return -EMSGSIZE;
 621
 622         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 623             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 624             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 625             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
 626                         session->peer_session_id) ||
 627             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 628             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
 629             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
 630             (session->mru &&
 631              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
 632                 goto nla_put_failure;
 633
 634         if ((session->ifname[0] &&
 635              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 636             (session->cookie_len &&
 637              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
 638                      &session->cookie[0])) ||
 639             (session->peer_cookie_len &&
 640              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
 641                      &session->peer_cookie[0])) ||
 642             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 643             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 644             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 645 #ifdef CONFIG_XFRM
 646             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
 647              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 648 #endif
 649             (session->reorder_timeout &&
 650              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
 651                 goto nla_put_failure;
 652
 653         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 654         if (nest == NULL)
 655                 goto nla_put_failure;
 656
 657         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS,
 658                 atomic_long_read(&session->stats.tx_packets)) ||
 659             nla_put_u64(skb, L2TP_ATTR_TX_BYTES,
 660                 atomic_long_read(&session->stats.tx_bytes)) ||
 661             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS,
 662                 atomic_long_read(&session->stats.tx_errors)) ||
 663             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS,
 664                 atomic_long_read(&session->stats.rx_packets)) ||
 665             nla_put_u64(skb, L2TP_ATTR_RX_BYTES,
 666                 atomic_long_read(&session->stats.rx_bytes)) ||
 667             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 668                 atomic_long_read(&session->stats.rx_seq_discards)) ||
 669             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 670                 atomic_long_read(&session->stats.rx_oos_packets)) ||
 671             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS,
 672                 atomic_long_read(&session->stats.rx_errors)))
 673                 goto nla_put_failure;
 674         nla_nest_end(skb, nest);
 675
 676         return genlmsg_end(skb, hdr);
 677
 678  nla_put_failure:
 679         genlmsg_cancel(skb, hdr);
 680         return -1;
 681 }
 682
 683 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 684 {
 685         struct l2tp_session *session;
 686         struct sk_buff *msg;
 687         int ret;
 688
 689         session = l2tp_nl_session_find(info);
 690         if (session == NULL) {
 691                 ret = -ENODEV;
 692                 goto out;
 693         }
 694
 695         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 696         if (!msg) {
 697                 ret = -ENOMEM;
 698                 goto out;
 699         }
 700
 701         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 702                                    0, session);
 703         if (ret < 0)
 704                 goto err_out;
 705
 706         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 707
 708 err_out:
 709         nlmsg_free(msg);
 710
 711 out:
 712         return ret;
 713 }
 714
 715 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 716 {
 717         struct net *net = sock_net(skb->sk);
 718         struct l2tp_session *session;
 719         struct l2tp_tunnel *tunnel = NULL;
 720         int ti = cb->args[0];
 721         int si = cb->args[1];
 722
 723         for (;;) {
 724                 if (tunnel == NULL) {
 725                         tunnel = l2tp_tunnel_find_nth(net, ti);
 726                         if (tunnel == NULL)
 727                                 goto out;
 728                 }
 729
 730                 session = l2tp_session_find_nth(tunnel, si);
 731                 if (session == NULL) {
 732                         ti++;
 733                         tunnel = NULL;
 734                         si = 0;
 735                         continue;
 736                 }
 737
 738                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 739                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 740                                          session) <= 0)
 741                         break;
 742
 743                 si++;
 744         }
 745
 746 out:
 747         cb->args[0] = ti;
 748         cb->args[1] = si;
 749
 750         return skb->len;
 751 }
 752
 753 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 754         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 755         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 756         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 757         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 758         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 759         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 760         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 761         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 762         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 763         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 764         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 765         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 766         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 767         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 768         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 769         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 770         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 771         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 772         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 773         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 774         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 775         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 776         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 777         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 778         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 779         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 780         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 781         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 782         [L2TP_ATTR_IP6_SADDR] = {
 783                 .type = NLA_BINARY,
 784                 .len = sizeof(struct in6_addr),
 785         },
 786         [L2TP_ATTR_IP6_DADDR] = {
 787                 .type = NLA_BINARY,
 788                 .len = sizeof(struct in6_addr),
 789         },
 790         [L2TP_ATTR_IFNAME] = {
 791                 .type = NLA_NUL_STRING,
 792                 .len = IFNAMSIZ - 1,
 793         },
 794         [L2TP_ATTR_COOKIE] = {
 795                 .type = NLA_BINARY,
 796                 .len = 8,
 797         },
 798         [L2TP_ATTR_PEER_COOKIE] = {
 799                 .type = NLA_BINARY,
 800                 .len = 8,
 801         },
 802 };
 803
 804 static const struct genl_ops l2tp_nl_ops[] = {
 805         {
 806                 .cmd = L2TP_CMD_NOOP,
 807                 .doit = l2tp_nl_cmd_noop,
 808                 .policy = l2tp_nl_policy,
 809                 /* can be retrieved by unprivileged users */
 810         },
 811         {
 812                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 813                 .doit = l2tp_nl_cmd_tunnel_create,
 814                 .policy = l2tp_nl_policy,
 815                 .flags = GENL_ADMIN_PERM,
 816         },
 817         {
 818                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 819                 .doit = l2tp_nl_cmd_tunnel_delete,
 820                 .policy = l2tp_nl_policy,
 821                 .flags = GENL_ADMIN_PERM,
 822         },
 823         {
 824                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 825                 .doit = l2tp_nl_cmd_tunnel_modify,
 826                 .policy = l2tp_nl_policy,
 827                 .flags = GENL_ADMIN_PERM,
 828         },
 829         {
 830                 .cmd = L2TP_CMD_TUNNEL_GET,
 831                 .doit = l2tp_nl_cmd_tunnel_get,
 832                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 833                 .policy = l2tp_nl_policy,
 834                 .flags = GENL_ADMIN_PERM,
 835         },
 836         {
 837                 .cmd = L2TP_CMD_SESSION_CREATE,
 838                 .doit = l2tp_nl_cmd_session_create,
 839                 .policy = l2tp_nl_policy,
 840                 .flags = GENL_ADMIN_PERM,
 841         },
 842         {
 843                 .cmd = L2TP_CMD_SESSION_DELETE,
 844                 .doit = l2tp_nl_cmd_session_delete,
 845                 .policy = l2tp_nl_policy,
 846                 .flags = GENL_ADMIN_PERM,
 847         },
 848         {
 849                 .cmd = L2TP_CMD_SESSION_MODIFY,
 850                 .doit = l2tp_nl_cmd_session_modify,
 851                 .policy = l2tp_nl_policy,
 852                 .flags = GENL_ADMIN_PERM,
 853         },
 854         {
 855                 .cmd = L2TP_CMD_SESSION_GET,
 856                 .doit = l2tp_nl_cmd_session_get,
 857                 .dumpit = l2tp_nl_cmd_session_dump,
 858                 .policy = l2tp_nl_policy,
 859                 .flags = GENL_ADMIN_PERM,
 860         },
 861 };
 862
 863 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 864 {
 865         int ret;
 866
 867         ret = -EINVAL;
 868         if (pw_type >= __L2TP_PWTYPE_MAX)
 869                 goto err;
 870
 871         genl_lock();
 872         ret = -EBUSY;
 873         if (l2tp_nl_cmd_ops[pw_type])
 874                 goto out;
 875
 876         l2tp_nl_cmd_ops[pw_type] = ops;
 877         ret = 0;
 878
 879 out:
 880         genl_unlock();
 881 err:
 882         return ret;
 883 }
 884 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 885
 886 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 887 {
 888         if (pw_type < __L2TP_PWTYPE_MAX) {
 889                 genl_lock();
 890                 l2tp_nl_cmd_ops[pw_type] = NULL;
 891                 genl_unlock();
 892         }
 893 }
 894 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 895
 896 static int l2tp_nl_init(void)
 897 {
 898         pr_info("L2TP netlink interface\n");
 899         return genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops);
 900 }
 901
 902 static void l2tp_nl_cleanup(void)
 903 {
 904         genl_unregister_family(&l2tp_nl_family);
 905 }
 906
 907 module_init(l2tp_nl_init);
 908 module_exit(l2tp_nl_cleanup);
 909
 910 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 911 MODULE_DESCRIPTION("L2TP netlink");
 912 MODULE_LICENSE("GPL");
 913 MODULE_VERSION("1.0");
 914 MODULE_ALIAS_GENL_FAMILY("l2tp");