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
 166         if (info->attrs[L2TP_ATTR_DEBUG])
 167                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 168
 169         tunnel = l2tp_tunnel_find(net, tunnel_id);
 170         if (tunnel != NULL) {
 171                 ret = -EEXIST;
 172                 goto out;
 173         }
 174
 175         ret = -EINVAL;
 176         switch (cfg.encap) {
 177         case L2TP_ENCAPTYPE_UDP:
 178         case L2TP_ENCAPTYPE_IP:
 179                 ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
 180                                          peer_tunnel_id, &cfg, &tunnel);
 181                 break;
 182         }
 183
 184 out:
 185         return ret;
 186 }
 187
 188 static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 189 {
 190         struct l2tp_tunnel *tunnel;
 191         u32 tunnel_id;
 192         int ret = 0;
 193         struct net *net = genl_info_net(info);
 194
 195         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 196                 ret = -EINVAL;
 197                 goto out;
 198         }
 199         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 200
 201         tunnel = l2tp_tunnel_find(net, tunnel_id);
 202         if (tunnel == NULL) {
 203                 ret = -ENODEV;
 204                 goto out;
 205         }
 206
 207         (void) l2tp_tunnel_delete(tunnel);
 208
 209 out:
 210         return ret;
 211 }
 212
 213 static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 214 {
 215         struct l2tp_tunnel *tunnel;
 216         u32 tunnel_id;
 217         int ret = 0;
 218         struct net *net = genl_info_net(info);
 219
 220         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 221                 ret = -EINVAL;
 222                 goto out;
 223         }
 224         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 225
 226         tunnel = l2tp_tunnel_find(net, tunnel_id);
 227         if (tunnel == NULL) {
 228                 ret = -ENODEV;
 229                 goto out;
 230         }
 231
 232         if (info->attrs[L2TP_ATTR_DEBUG])
 233                 tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 234
 235 out:
 236         return ret;
 237 }
 238
 239 static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 240                                struct l2tp_tunnel *tunnel)
 241 {
 242         void *hdr;
 243         struct nlattr *nest;
 244         struct sock *sk = NULL;
 245         struct inet_sock *inet;
 246 #if IS_ENABLED(CONFIG_IPV6)
 247         struct ipv6_pinfo *np = NULL;
 248 #endif
 249         struct l2tp_stats stats;
 250         unsigned int start;
 251
 252         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags,
 253                           L2TP_CMD_TUNNEL_GET);
 254         if (!hdr)
 255                 return -EMSGSIZE;
 256
 257         if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 258             nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 259             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 260             nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
 261             nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 262                 goto nla_put_failure;
 263
 264         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 265         if (nest == NULL)
 266                 goto nla_put_failure;
 267
 268         do {
 269                 start = u64_stats_fetch_begin(&tunnel->stats.syncp);
 270                 stats.tx_packets = tunnel->stats.tx_packets;
 271                 stats.tx_bytes = tunnel->stats.tx_bytes;
 272                 stats.tx_errors = tunnel->stats.tx_errors;
 273                 stats.rx_packets = tunnel->stats.rx_packets;
 274                 stats.rx_bytes = tunnel->stats.rx_bytes;
 275                 stats.rx_errors = tunnel->stats.rx_errors;
 276                 stats.rx_seq_discards = tunnel->stats.rx_seq_discards;
 277                 stats.rx_oos_packets = tunnel->stats.rx_oos_packets;
 278         } while (u64_stats_fetch_retry(&tunnel->stats.syncp, start));
 279
 280         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
 281             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
 282             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
 283             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
 284             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
 285             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 286                         stats.rx_seq_discards) ||
 287             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 288                         stats.rx_oos_packets) ||
 289             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
 290                 goto nla_put_failure;
 291         nla_nest_end(skb, nest);
 292
 293         sk = tunnel->sock;
 294         if (!sk)
 295                 goto out;
 296
 297 #if IS_ENABLED(CONFIG_IPV6)
 298         if (sk->sk_family == AF_INET6)
 299                 np = inet6_sk(sk);
 300 #endif
 301
 302         inet = inet_sk(sk);
 303
 304         switch (tunnel->encap) {
 305         case L2TP_ENCAPTYPE_UDP:
 306                 if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 307                     nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)) ||
 308                     nla_put_u8(skb, L2TP_ATTR_UDP_CSUM,
 309                                (sk->sk_no_check != UDP_CSUM_NOXMIT)))
 310                         goto nla_put_failure;
 311                 /* NOBREAK */
 312         case L2TP_ENCAPTYPE_IP:
 313 #if IS_ENABLED(CONFIG_IPV6)
 314                 if (np) {
 315                         if (nla_put(skb, L2TP_ATTR_IP6_SADDR, sizeof(np->saddr),
 316                                     &np->saddr) ||
 317                             nla_put(skb, L2TP_ATTR_IP6_DADDR, sizeof(np->daddr),
 318                                     &np->daddr))
 319                                 goto nla_put_failure;
 320                 } else
 321 #endif
 322                 if (nla_put_be32(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 323                     nla_put_be32(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 324                         goto nla_put_failure;
 325                 break;
 326         }
 327
 328 out:
 329         return genlmsg_end(skb, hdr);
 330
 331 nla_put_failure:
 332         genlmsg_cancel(skb, hdr);
 333         return -1;
 334 }
 335
 336 static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 337 {
 338         struct l2tp_tunnel *tunnel;
 339         struct sk_buff *msg;
 340         u32 tunnel_id;
 341         int ret = -ENOBUFS;
 342         struct net *net = genl_info_net(info);
 343
 344         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 345                 ret = -EINVAL;
 346                 goto out;
 347         }
 348
 349         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 350
 351         tunnel = l2tp_tunnel_find(net, tunnel_id);
 352         if (tunnel == NULL) {
 353                 ret = -ENODEV;
 354                 goto out;
 355         }
 356
 357         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 358         if (!msg) {
 359                 ret = -ENOMEM;
 360                 goto out;
 361         }
 362
 363         ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 364                                   NLM_F_ACK, tunnel);
 365         if (ret < 0)
 366                 goto err_out;
 367
 368         return genlmsg_unicast(net, msg, info->snd_portid);
 369
 370 err_out:
 371         nlmsg_free(msg);
 372
 373 out:
 374         return ret;
 375 }
 376
 377 static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 378 {
 379         int ti = cb->args[0];
 380         struct l2tp_tunnel *tunnel;
 381         struct net *net = sock_net(skb->sk);
 382
 383         for (;;) {
 384                 tunnel = l2tp_tunnel_find_nth(net, ti);
 385                 if (tunnel == NULL)
 386                         goto out;
 387
 388                 if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 389                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
 390                                         tunnel) <= 0)
 391                         goto out;
 392
 393                 ti++;
 394         }
 395
 396 out:
 397         cb->args[0] = ti;
 398
 399         return skb->len;
 400 }
 401
 402 static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 403 {
 404         u32 tunnel_id = 0;
 405         u32 session_id;
 406         u32 peer_session_id;
 407         int ret = 0;
 408         struct l2tp_tunnel *tunnel;
 409         struct l2tp_session *session;
 410         struct l2tp_session_cfg cfg = { 0, };
 411         struct net *net = genl_info_net(info);
 412
 413         if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 414                 ret = -EINVAL;
 415                 goto out;
 416         }
 417         tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 418         tunnel = l2tp_tunnel_find(net, tunnel_id);
 419         if (!tunnel) {
 420                 ret = -ENODEV;
 421                 goto out;
 422         }
 423
 424         if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 425                 ret = -EINVAL;
 426                 goto out;
 427         }
 428         session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 429         session = l2tp_session_find(net, tunnel, session_id);
 430         if (session) {
 431                 ret = -EEXIST;
 432                 goto out;
 433         }
 434
 435         if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 436                 ret = -EINVAL;
 437                 goto out;
 438         }
 439         peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 440
 441         if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 442                 ret = -EINVAL;
 443                 goto out;
 444         }
 445         cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 446         if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 447                 ret = -EINVAL;
 448                 goto out;
 449         }
 450
 451         if (tunnel->version > 2) {
 452                 if (info->attrs[L2TP_ATTR_OFFSET])
 453                         cfg.offset = nla_get_u16(info->attrs[L2TP_ATTR_OFFSET]);
 454
 455                 if (info->attrs[L2TP_ATTR_DATA_SEQ])
 456                         cfg.data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 457
 458                 cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 459                 if (info->attrs[L2TP_ATTR_L2SPEC_TYPE])
 460                         cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 461
 462                 cfg.l2specific_len = 4;
 463                 if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
 464                         cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
 465
 466                 if (info->attrs[L2TP_ATTR_COOKIE]) {
 467                         u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 468                         if (len > 8) {
 469                                 ret = -EINVAL;
 470                                 goto out;
 471                         }
 472                         cfg.cookie_len = len;
 473                         memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 474                 }
 475                 if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 476                         u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 477                         if (len > 8) {
 478                                 ret = -EINVAL;
 479                                 goto out;
 480                         }
 481                         cfg.peer_cookie_len = len;
 482                         memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 483                 }
 484                 if (info->attrs[L2TP_ATTR_IFNAME])
 485                         cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 486
 487                 if (info->attrs[L2TP_ATTR_VLAN_ID])
 488                         cfg.vlan_id = nla_get_u16(info->attrs[L2TP_ATTR_VLAN_ID]);
 489         }
 490
 491         if (info->attrs[L2TP_ATTR_DEBUG])
 492                 cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 493
 494         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 495                 cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 496
 497         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 498                 cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 499
 500         if (info->attrs[L2TP_ATTR_LNS_MODE])
 501                 cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 502
 503         if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 504                 cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 505
 506         if (info->attrs[L2TP_ATTR_MTU])
 507                 cfg.mtu = nla_get_u16(info->attrs[L2TP_ATTR_MTU]);
 508
 509         if (info->attrs[L2TP_ATTR_MRU])
 510                 cfg.mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 511
 512         if ((l2tp_nl_cmd_ops[cfg.pw_type] == NULL) ||
 513             (l2tp_nl_cmd_ops[cfg.pw_type]->session_create == NULL)) {
 514                 ret = -EPROTONOSUPPORT;
 515                 goto out;
 516         }
 517
 518         /* Check that pseudowire-specific params are present */
 519         switch (cfg.pw_type) {
 520         case L2TP_PWTYPE_NONE:
 521                 break;
 522         case L2TP_PWTYPE_ETH_VLAN:
 523                 if (!info->attrs[L2TP_ATTR_VLAN_ID]) {
 524                         ret = -EINVAL;
 525                         goto out;
 526                 }
 527                 break;
 528         case L2TP_PWTYPE_ETH:
 529                 break;
 530         case L2TP_PWTYPE_PPP:
 531         case L2TP_PWTYPE_PPP_AC:
 532                 break;
 533         case L2TP_PWTYPE_IP:
 534         default:
 535                 ret = -EPROTONOSUPPORT;
 536                 break;
 537         }
 538
 539         ret = -EPROTONOSUPPORT;
 540         if (l2tp_nl_cmd_ops[cfg.pw_type]->session_create)
 541                 ret = (*l2tp_nl_cmd_ops[cfg.pw_type]->session_create)(net, tunnel_id,
 542                         session_id, peer_session_id, &cfg);
 543
 544 out:
 545         return ret;
 546 }
 547
 548 static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 549 {
 550         int ret = 0;
 551         struct l2tp_session *session;
 552         u16 pw_type;
 553
 554         session = l2tp_nl_session_find(info);
 555         if (session == NULL) {
 556                 ret = -ENODEV;
 557                 goto out;
 558         }
 559
 560         pw_type = session->pwtype;
 561         if (pw_type < __L2TP_PWTYPE_MAX)
 562                 if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 563                         ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 564
 565 out:
 566         return ret;
 567 }
 568
 569 static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 570 {
 571         int ret = 0;
 572         struct l2tp_session *session;
 573
 574         session = l2tp_nl_session_find(info);
 575         if (session == NULL) {
 576                 ret = -ENODEV;
 577                 goto out;
 578         }
 579
 580         if (info->attrs[L2TP_ATTR_DEBUG])
 581                 session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 582
 583         if (info->attrs[L2TP_ATTR_DATA_SEQ])
 584                 session->data_seq = nla_get_u8(info->attrs[L2TP_ATTR_DATA_SEQ]);
 585
 586         if (info->attrs[L2TP_ATTR_RECV_SEQ])
 587                 session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 588
 589         if (info->attrs[L2TP_ATTR_SEND_SEQ])
 590                 session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 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         struct l2tp_stats stats;
 616         unsigned int start;
 617
 618         sk = tunnel->sock;
 619
 620         hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, L2TP_CMD_SESSION_GET);
 621         if (!hdr)
 622                 return -EMSGSIZE;
 623
 624         if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 625             nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 626             nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 627             nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID,
 628                         session->peer_session_id) ||
 629             nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 630             nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype) ||
 631             nla_put_u16(skb, L2TP_ATTR_MTU, session->mtu) ||
 632             (session->mru &&
 633              nla_put_u16(skb, L2TP_ATTR_MRU, session->mru)))
 634                 goto nla_put_failure;
 635
 636         if ((session->ifname[0] &&
 637              nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 638             (session->cookie_len &&
 639              nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len,
 640                      &session->cookie[0])) ||
 641             (session->peer_cookie_len &&
 642              nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len,
 643                      &session->peer_cookie[0])) ||
 644             nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 645             nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 646             nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 647 #ifdef CONFIG_XFRM
 648             (((sk) && (sk->sk_policy[0] || sk->sk_policy[1])) &&
 649              nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 650 #endif
 651             (session->reorder_timeout &&
 652              nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, session->reorder_timeout)))
 653                 goto nla_put_failure;
 654
 655         nest = nla_nest_start(skb, L2TP_ATTR_STATS);
 656         if (nest == NULL)
 657                 goto nla_put_failure;
 658
 659         do {
 660                 start = u64_stats_fetch_begin(&session->stats.syncp);
 661                 stats.tx_packets = session->stats.tx_packets;
 662                 stats.tx_bytes = session->stats.tx_bytes;
 663                 stats.tx_errors = session->stats.tx_errors;
 664                 stats.rx_packets = session->stats.rx_packets;
 665                 stats.rx_bytes = session->stats.rx_bytes;
 666                 stats.rx_errors = session->stats.rx_errors;
 667                 stats.rx_seq_discards = session->stats.rx_seq_discards;
 668                 stats.rx_oos_packets = session->stats.rx_oos_packets;
 669         } while (u64_stats_fetch_retry(&session->stats.syncp, start));
 670
 671         if (nla_put_u64(skb, L2TP_ATTR_TX_PACKETS, stats.tx_packets) ||
 672             nla_put_u64(skb, L2TP_ATTR_TX_BYTES, stats.tx_bytes) ||
 673             nla_put_u64(skb, L2TP_ATTR_TX_ERRORS, stats.tx_errors) ||
 674             nla_put_u64(skb, L2TP_ATTR_RX_PACKETS, stats.rx_packets) ||
 675             nla_put_u64(skb, L2TP_ATTR_RX_BYTES, stats.rx_bytes) ||
 676             nla_put_u64(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 677                         stats.rx_seq_discards) ||
 678             nla_put_u64(skb, L2TP_ATTR_RX_OOS_PACKETS,
 679                         stats.rx_oos_packets) ||
 680             nla_put_u64(skb, L2TP_ATTR_RX_ERRORS, stats.rx_errors))
 681                 goto nla_put_failure;
 682         nla_nest_end(skb, nest);
 683
 684         return genlmsg_end(skb, hdr);
 685
 686  nla_put_failure:
 687         genlmsg_cancel(skb, hdr);
 688         return -1;
 689 }
 690
 691 static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 692 {
 693         struct l2tp_session *session;
 694         struct sk_buff *msg;
 695         int ret;
 696
 697         session = l2tp_nl_session_find(info);
 698         if (session == NULL) {
 699                 ret = -ENODEV;
 700                 goto out;
 701         }
 702
 703         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 704         if (!msg) {
 705                 ret = -ENOMEM;
 706                 goto out;
 707         }
 708
 709         ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 710                                    0, session);
 711         if (ret < 0)
 712                 goto err_out;
 713
 714         return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 715
 716 err_out:
 717         nlmsg_free(msg);
 718
 719 out:
 720         return ret;
 721 }
 722
 723 static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 724 {
 725         struct net *net = sock_net(skb->sk);
 726         struct l2tp_session *session;
 727         struct l2tp_tunnel *tunnel = NULL;
 728         int ti = cb->args[0];
 729         int si = cb->args[1];
 730
 731         for (;;) {
 732                 if (tunnel == NULL) {
 733                         tunnel = l2tp_tunnel_find_nth(net, ti);
 734                         if (tunnel == NULL)
 735                                 goto out;
 736                 }
 737
 738                 session = l2tp_session_find_nth(tunnel, si);
 739                 if (session == NULL) {
 740                         ti++;
 741                         tunnel = NULL;
 742                         si = 0;
 743                         continue;
 744                 }
 745
 746                 if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 747                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
 748                                          session) <= 0)
 749                         break;
 750
 751                 si++;
 752         }
 753
 754 out:
 755         cb->args[0] = ti;
 756         cb->args[1] = si;
 757
 758         return skb->len;
 759 }
 760
 761 static struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 762         [L2TP_ATTR_NONE]                = { .type = NLA_UNSPEC, },
 763         [L2TP_ATTR_PW_TYPE]             = { .type = NLA_U16, },
 764         [L2TP_ATTR_ENCAP_TYPE]          = { .type = NLA_U16, },
 765         [L2TP_ATTR_OFFSET]              = { .type = NLA_U16, },
 766         [L2TP_ATTR_DATA_SEQ]            = { .type = NLA_U8, },
 767         [L2TP_ATTR_L2SPEC_TYPE]         = { .type = NLA_U8, },
 768         [L2TP_ATTR_L2SPEC_LEN]          = { .type = NLA_U8, },
 769         [L2TP_ATTR_PROTO_VERSION]       = { .type = NLA_U8, },
 770         [L2TP_ATTR_CONN_ID]             = { .type = NLA_U32, },
 771         [L2TP_ATTR_PEER_CONN_ID]        = { .type = NLA_U32, },
 772         [L2TP_ATTR_SESSION_ID]          = { .type = NLA_U32, },
 773         [L2TP_ATTR_PEER_SESSION_ID]     = { .type = NLA_U32, },
 774         [L2TP_ATTR_UDP_CSUM]            = { .type = NLA_U8, },
 775         [L2TP_ATTR_VLAN_ID]             = { .type = NLA_U16, },
 776         [L2TP_ATTR_DEBUG]               = { .type = NLA_U32, },
 777         [L2TP_ATTR_RECV_SEQ]            = { .type = NLA_U8, },
 778         [L2TP_ATTR_SEND_SEQ]            = { .type = NLA_U8, },
 779         [L2TP_ATTR_LNS_MODE]            = { .type = NLA_U8, },
 780         [L2TP_ATTR_USING_IPSEC]         = { .type = NLA_U8, },
 781         [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
 782         [L2TP_ATTR_FD]                  = { .type = NLA_U32, },
 783         [L2TP_ATTR_IP_SADDR]            = { .type = NLA_U32, },
 784         [L2TP_ATTR_IP_DADDR]            = { .type = NLA_U32, },
 785         [L2TP_ATTR_UDP_SPORT]           = { .type = NLA_U16, },
 786         [L2TP_ATTR_UDP_DPORT]           = { .type = NLA_U16, },
 787         [L2TP_ATTR_MTU]                 = { .type = NLA_U16, },
 788         [L2TP_ATTR_MRU]                 = { .type = NLA_U16, },
 789         [L2TP_ATTR_STATS]               = { .type = NLA_NESTED, },
 790         [L2TP_ATTR_IP6_SADDR] = {
 791                 .type = NLA_BINARY,
 792                 .len = sizeof(struct in6_addr),
 793         },
 794         [L2TP_ATTR_IP6_DADDR] = {
 795                 .type = NLA_BINARY,
 796                 .len = sizeof(struct in6_addr),
 797         },
 798         [L2TP_ATTR_IFNAME] = {
 799                 .type = NLA_NUL_STRING,
 800                 .len = IFNAMSIZ - 1,
 801         },
 802         [L2TP_ATTR_COOKIE] = {
 803                 .type = NLA_BINARY,
 804                 .len = 8,
 805         },
 806         [L2TP_ATTR_PEER_COOKIE] = {
 807                 .type = NLA_BINARY,
 808                 .len = 8,
 809         },
 810 };
 811
 812 static struct genl_ops l2tp_nl_ops[] = {
 813         {
 814                 .cmd = L2TP_CMD_NOOP,
 815                 .doit = l2tp_nl_cmd_noop,
 816                 .policy = l2tp_nl_policy,
 817                 /* can be retrieved by unprivileged users */
 818         },
 819         {
 820                 .cmd = L2TP_CMD_TUNNEL_CREATE,
 821                 .doit = l2tp_nl_cmd_tunnel_create,
 822                 .policy = l2tp_nl_policy,
 823                 .flags = GENL_ADMIN_PERM,
 824         },
 825         {
 826                 .cmd = L2TP_CMD_TUNNEL_DELETE,
 827                 .doit = l2tp_nl_cmd_tunnel_delete,
 828                 .policy = l2tp_nl_policy,
 829                 .flags = GENL_ADMIN_PERM,
 830         },
 831         {
 832                 .cmd = L2TP_CMD_TUNNEL_MODIFY,
 833                 .doit = l2tp_nl_cmd_tunnel_modify,
 834                 .policy = l2tp_nl_policy,
 835                 .flags = GENL_ADMIN_PERM,
 836         },
 837         {
 838                 .cmd = L2TP_CMD_TUNNEL_GET,
 839                 .doit = l2tp_nl_cmd_tunnel_get,
 840                 .dumpit = l2tp_nl_cmd_tunnel_dump,
 841                 .policy = l2tp_nl_policy,
 842                 .flags = GENL_ADMIN_PERM,
 843         },
 844         {
 845                 .cmd = L2TP_CMD_SESSION_CREATE,
 846                 .doit = l2tp_nl_cmd_session_create,
 847                 .policy = l2tp_nl_policy,
 848                 .flags = GENL_ADMIN_PERM,
 849         },
 850         {
 851                 .cmd = L2TP_CMD_SESSION_DELETE,
 852                 .doit = l2tp_nl_cmd_session_delete,
 853                 .policy = l2tp_nl_policy,
 854                 .flags = GENL_ADMIN_PERM,
 855         },
 856         {
 857                 .cmd = L2TP_CMD_SESSION_MODIFY,
 858                 .doit = l2tp_nl_cmd_session_modify,
 859                 .policy = l2tp_nl_policy,
 860                 .flags = GENL_ADMIN_PERM,
 861         },
 862         {
 863                 .cmd = L2TP_CMD_SESSION_GET,
 864                 .doit = l2tp_nl_cmd_session_get,
 865                 .dumpit = l2tp_nl_cmd_session_dump,
 866                 .policy = l2tp_nl_policy,
 867                 .flags = GENL_ADMIN_PERM,
 868         },
 869 };
 870
 871 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 872 {
 873         int ret;
 874
 875         ret = -EINVAL;
 876         if (pw_type >= __L2TP_PWTYPE_MAX)
 877                 goto err;
 878
 879         genl_lock();
 880         ret = -EBUSY;
 881         if (l2tp_nl_cmd_ops[pw_type])
 882                 goto out;
 883
 884         l2tp_nl_cmd_ops[pw_type] = ops;
 885         ret = 0;
 886
 887 out:
 888         genl_unlock();
 889 err:
 890         return ret;
 891 }
 892 EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
 893
 894 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
 895 {
 896         if (pw_type < __L2TP_PWTYPE_MAX) {
 897                 genl_lock();
 898                 l2tp_nl_cmd_ops[pw_type] = NULL;
 899                 genl_unlock();
 900         }
 901 }
 902 EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
 903
 904 static int l2tp_nl_init(void)
 905 {
 906         int err;
 907
 908         pr_info("L2TP netlink interface\n");
 909         err = genl_register_family_with_ops(&l2tp_nl_family, l2tp_nl_ops,
 910                                             ARRAY_SIZE(l2tp_nl_ops));
 911
 912         return err;
 913 }
 914
 915 static void l2tp_nl_cleanup(void)
 916 {
 917         genl_unregister_family(&l2tp_nl_family);
 918 }
 919
 920 module_init(l2tp_nl_init);
 921 module_exit(l2tp_nl_cleanup);
 922
 923 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 924 MODULE_DESCRIPTION("L2TP netlink");
 925 MODULE_LICENSE("GPL");
 926 MODULE_VERSION("1.0");
 927 MODULE_ALIAS_GENL_FAMILY("l2tp");