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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   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
  13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15#include <net/sock.h>
  16#include <net/genetlink.h>
  17#include <net/udp.h>
  18#include <linux/in.h>
  19#include <linux/udp.h>
  20#include <linux/socket.h>
  21#include <linux/module.h>
  22#include <linux/list.h>
  23#include <net/net_namespace.h>
  24
  25#include <linux/l2tp.h>
  26
  27#include "l2tp_core.h"
  28
  29static struct genl_family l2tp_nl_family;
  30
  31static const struct genl_multicast_group l2tp_multicast_group[] = {
  32	{
  33		.name = L2TP_GENL_MCGROUP,
  34	},
  35};
  36
  37static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq,
  38			       int flags, struct l2tp_tunnel *tunnel, u8 cmd);
  39static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq,
  40				int flags, struct l2tp_session *session,
  41				u8 cmd);
  42
  43/* Accessed under genl lock */
  44static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
  45
  46static struct l2tp_session *l2tp_nl_session_get(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_get_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_get(net, tunnel_id);
  63		if (tunnel) {
  64			session = l2tp_tunnel_get_session(tunnel, session_id);
  65			l2tp_tunnel_dec_refcount(tunnel);
  66		}
  67	}
  68
  69	return session;
  70}
  71
  72static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
  73{
  74	struct sk_buff *msg;
  75	void *hdr;
  76	int ret = -ENOBUFS;
  77
  78	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  79	if (!msg) {
  80		ret = -ENOMEM;
  81		goto out;
  82	}
  83
  84	hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
  85			  &l2tp_nl_family, 0, L2TP_CMD_NOOP);
  86	if (!hdr) {
  87		ret = -EMSGSIZE;
  88		goto err_out;
  89	}
  90
  91	genlmsg_end(msg, hdr);
  92
  93	return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
  94
  95err_out:
  96	nlmsg_free(msg);
  97
  98out:
  99	return ret;
 100}
 101
 102static int l2tp_tunnel_notify(struct genl_family *family,
 103			      struct genl_info *info,
 104			      struct l2tp_tunnel *tunnel,
 105			      u8 cmd)
 106{
 107	struct sk_buff *msg;
 108	int ret;
 109
 110	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 111	if (!msg)
 112		return -ENOMEM;
 113
 114	ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 115				  NLM_F_ACK, tunnel, cmd);
 116
 117	if (ret >= 0) {
 118		ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
 119		/* We don't care if no one is listening */
 120		if (ret == -ESRCH)
 121			ret = 0;
 122		return ret;
 123	}
 124
 125	nlmsg_free(msg);
 126
 127	return ret;
 128}
 129
 130static int l2tp_session_notify(struct genl_family *family,
 131			       struct genl_info *info,
 132			       struct l2tp_session *session,
 133			       u8 cmd)
 134{
 135	struct sk_buff *msg;
 136	int ret;
 137
 138	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 139	if (!msg)
 140		return -ENOMEM;
 141
 142	ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 143				   NLM_F_ACK, session, cmd);
 144
 145	if (ret >= 0) {
 146		ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
 147		/* We don't care if no one is listening */
 148		if (ret == -ESRCH)
 149			ret = 0;
 150		return ret;
 151	}
 152
 153	nlmsg_free(msg);
 154
 155	return ret;
 156}
 157
 158static int l2tp_nl_cmd_tunnel_create_get_addr(struct nlattr **attrs, struct l2tp_tunnel_cfg *cfg)
 159{
 160	if (attrs[L2TP_ATTR_UDP_SPORT])
 161		cfg->local_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_SPORT]);
 162	if (attrs[L2TP_ATTR_UDP_DPORT])
 163		cfg->peer_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_DPORT]);
 164	cfg->use_udp_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_CSUM]);
 165
 166	/* Must have either AF_INET or AF_INET6 address for source and destination */
 167#if IS_ENABLED(CONFIG_IPV6)
 168	if (attrs[L2TP_ATTR_IP6_SADDR] && attrs[L2TP_ATTR_IP6_DADDR]) {
 169		cfg->local_ip6 = nla_data(attrs[L2TP_ATTR_IP6_SADDR]);
 170		cfg->peer_ip6 = nla_data(attrs[L2TP_ATTR_IP6_DADDR]);
 171		cfg->udp6_zero_tx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
 172		cfg->udp6_zero_rx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
 173		return 0;
 174	}
 175#endif
 176	if (attrs[L2TP_ATTR_IP_SADDR] && attrs[L2TP_ATTR_IP_DADDR]) {
 177		cfg->local_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_SADDR]);
 178		cfg->peer_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_DADDR]);
 179		return 0;
 180	}
 181	return -EINVAL;
 182}
 183
 184static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
 185{
 186	u32 tunnel_id;
 187	u32 peer_tunnel_id;
 188	int proto_version;
 189	int fd = -1;
 190	int ret = 0;
 191	struct l2tp_tunnel_cfg cfg = { 0, };
 192	struct l2tp_tunnel *tunnel;
 193	struct net *net = genl_info_net(info);
 194	struct nlattr **attrs = info->attrs;
 195
 196	if (!attrs[L2TP_ATTR_CONN_ID]) {
 197		ret = -EINVAL;
 198		goto out;
 199	}
 200	tunnel_id = nla_get_u32(attrs[L2TP_ATTR_CONN_ID]);
 201
 202	if (!attrs[L2TP_ATTR_PEER_CONN_ID]) {
 203		ret = -EINVAL;
 204		goto out;
 205	}
 206	peer_tunnel_id = nla_get_u32(attrs[L2TP_ATTR_PEER_CONN_ID]);
 207
 208	if (!attrs[L2TP_ATTR_PROTO_VERSION]) {
 209		ret = -EINVAL;
 210		goto out;
 211	}
 212	proto_version = nla_get_u8(attrs[L2TP_ATTR_PROTO_VERSION]);
 213
 214	if (!attrs[L2TP_ATTR_ENCAP_TYPE]) {
 215		ret = -EINVAL;
 216		goto out;
 217	}
 218	cfg.encap = nla_get_u16(attrs[L2TP_ATTR_ENCAP_TYPE]);
 219
 220	/* Managed tunnels take the tunnel socket from userspace.
 221	 * Unmanaged tunnels must call out the source and destination addresses
 222	 * for the kernel to create the tunnel socket itself.
 223	 */
 224	if (attrs[L2TP_ATTR_FD]) {
 225		fd = nla_get_u32(attrs[L2TP_ATTR_FD]);
 226	} else {
 227		ret = l2tp_nl_cmd_tunnel_create_get_addr(attrs, &cfg);
 228		if (ret < 0)
 229			goto out;
 230	}
 231
 
 
 
 232	ret = -EINVAL;
 233	switch (cfg.encap) {
 234	case L2TP_ENCAPTYPE_UDP:
 235	case L2TP_ENCAPTYPE_IP:
 236		ret = l2tp_tunnel_create(fd, proto_version, tunnel_id,
 237					 peer_tunnel_id, &cfg, &tunnel);
 238		break;
 239	}
 240
 241	if (ret < 0)
 242		goto out;
 243
 244	l2tp_tunnel_inc_refcount(tunnel);
 245	ret = l2tp_tunnel_register(tunnel, net, &cfg);
 246	if (ret < 0) {
 247		kfree(tunnel);
 248		goto out;
 249	}
 250	ret = l2tp_tunnel_notify(&l2tp_nl_family, info, tunnel,
 251				 L2TP_CMD_TUNNEL_CREATE);
 252	l2tp_tunnel_dec_refcount(tunnel);
 253
 254out:
 255	return ret;
 256}
 257
 258static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 259{
 260	struct l2tp_tunnel *tunnel;
 261	u32 tunnel_id;
 262	int ret = 0;
 263	struct net *net = genl_info_net(info);
 264
 265	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 266		ret = -EINVAL;
 267		goto out;
 268	}
 269	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 270
 271	tunnel = l2tp_tunnel_get(net, tunnel_id);
 272	if (!tunnel) {
 273		ret = -ENODEV;
 274		goto out;
 275	}
 276
 277	l2tp_tunnel_notify(&l2tp_nl_family, info,
 278			   tunnel, L2TP_CMD_TUNNEL_DELETE);
 279
 280	l2tp_tunnel_delete(tunnel);
 281
 282	l2tp_tunnel_dec_refcount(tunnel);
 283
 284out:
 285	return ret;
 286}
 287
 288static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 289{
 290	struct l2tp_tunnel *tunnel;
 291	u32 tunnel_id;
 292	int ret = 0;
 293	struct net *net = genl_info_net(info);
 294
 295	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 296		ret = -EINVAL;
 297		goto out;
 298	}
 299	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 300
 301	tunnel = l2tp_tunnel_get(net, tunnel_id);
 302	if (!tunnel) {
 303		ret = -ENODEV;
 304		goto out;
 305	}
 306
 
 
 
 307	ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 308				 tunnel, L2TP_CMD_TUNNEL_MODIFY);
 309
 310	l2tp_tunnel_dec_refcount(tunnel);
 311
 312out:
 313	return ret;
 314}
 315
 316#if IS_ENABLED(CONFIG_IPV6)
 317static int l2tp_nl_tunnel_send_addr6(struct sk_buff *skb, struct sock *sk,
 318				     enum l2tp_encap_type encap)
 319{
 320	struct inet_sock *inet = inet_sk(sk);
 321	struct ipv6_pinfo *np = inet6_sk(sk);
 322
 323	switch (encap) {
 324	case L2TP_ENCAPTYPE_UDP:
 325		if (udp_get_no_check6_tx(sk) &&
 326		    nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_TX))
 327			return -1;
 328		if (udp_get_no_check6_rx(sk) &&
 329		    nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_RX))
 330			return -1;
 331		if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 332		    nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
 333			return -1;
 334		fallthrough;
 335	case L2TP_ENCAPTYPE_IP:
 336		if (nla_put_in6_addr(skb, L2TP_ATTR_IP6_SADDR, &np->saddr) ||
 337		    nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR, &sk->sk_v6_daddr))
 338			return -1;
 339		break;
 340	}
 341	return 0;
 342}
 343#endif
 344
 345static int l2tp_nl_tunnel_send_addr4(struct sk_buff *skb, struct sock *sk,
 346				     enum l2tp_encap_type encap)
 347{
 348	struct inet_sock *inet = inet_sk(sk);
 349
 350	switch (encap) {
 351	case L2TP_ENCAPTYPE_UDP:
 352		if (nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx) ||
 353		    nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 354		    nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
 355			return -1;
 356		fallthrough;
 357	case L2TP_ENCAPTYPE_IP:
 358		if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 359		    nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 360			return -1;
 361		break;
 362	}
 363
 364	return 0;
 365}
 366
 367/* Append attributes for the tunnel address, handling the different attribute types
 368 * used for different tunnel encapsulation and AF_INET v.s. AF_INET6.
 369 */
 370static int l2tp_nl_tunnel_send_addr(struct sk_buff *skb, struct l2tp_tunnel *tunnel)
 371{
 372	struct sock *sk = tunnel->sock;
 373
 374	if (!sk)
 375		return 0;
 376
 377#if IS_ENABLED(CONFIG_IPV6)
 378	if (sk->sk_family == AF_INET6)
 379		return l2tp_nl_tunnel_send_addr6(skb, sk, tunnel->encap);
 380#endif
 381	return l2tp_nl_tunnel_send_addr4(skb, sk, tunnel->encap);
 382}
 383
 384static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 385			       struct l2tp_tunnel *tunnel, u8 cmd)
 386{
 387	void *hdr;
 388	struct nlattr *nest;
 389
 390	hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 391	if (!hdr)
 392		return -EMSGSIZE;
 393
 394	if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 395	    nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 396	    nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 397	    nla_put_u32(skb, L2TP_ATTR_DEBUG, 0) ||
 398	    nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 399		goto nla_put_failure;
 400
 401	nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS);
 402	if (!nest)
 403		goto nla_put_failure;
 404
 405	if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
 406			      atomic_long_read(&tunnel->stats.tx_packets),
 407			      L2TP_ATTR_STATS_PAD) ||
 408	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
 409			      atomic_long_read(&tunnel->stats.tx_bytes),
 410			      L2TP_ATTR_STATS_PAD) ||
 411	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
 412			      atomic_long_read(&tunnel->stats.tx_errors),
 413			      L2TP_ATTR_STATS_PAD) ||
 414	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
 415			      atomic_long_read(&tunnel->stats.rx_packets),
 416			      L2TP_ATTR_STATS_PAD) ||
 417	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
 418			      atomic_long_read(&tunnel->stats.rx_bytes),
 419			      L2TP_ATTR_STATS_PAD) ||
 420	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 421			      atomic_long_read(&tunnel->stats.rx_seq_discards),
 422			      L2TP_ATTR_STATS_PAD) ||
 423	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_COOKIE_DISCARDS,
 424			      atomic_long_read(&tunnel->stats.rx_cookie_discards),
 425			      L2TP_ATTR_STATS_PAD) ||
 426	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
 427			      atomic_long_read(&tunnel->stats.rx_oos_packets),
 428			      L2TP_ATTR_STATS_PAD) ||
 429	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
 430			      atomic_long_read(&tunnel->stats.rx_errors),
 431			      L2TP_ATTR_STATS_PAD) ||
 432	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_INVALID,
 433			      atomic_long_read(&tunnel->stats.rx_invalid),
 434			      L2TP_ATTR_STATS_PAD))
 435		goto nla_put_failure;
 436	nla_nest_end(skb, nest);
 437
 438	if (l2tp_nl_tunnel_send_addr(skb, tunnel))
 439		goto nla_put_failure;
 440
 441	genlmsg_end(skb, hdr);
 442	return 0;
 443
 444nla_put_failure:
 445	genlmsg_cancel(skb, hdr);
 446	return -1;
 447}
 448
 449static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 450{
 451	struct l2tp_tunnel *tunnel;
 452	struct sk_buff *msg;
 453	u32 tunnel_id;
 454	int ret = -ENOBUFS;
 455	struct net *net = genl_info_net(info);
 456
 457	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 458		ret = -EINVAL;
 459		goto err;
 460	}
 461
 462	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 463
 464	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 465	if (!msg) {
 466		ret = -ENOMEM;
 467		goto err;
 468	}
 469
 470	tunnel = l2tp_tunnel_get(net, tunnel_id);
 471	if (!tunnel) {
 472		ret = -ENODEV;
 473		goto err_nlmsg;
 474	}
 475
 476	ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 477				  NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
 478	if (ret < 0)
 479		goto err_nlmsg_tunnel;
 480
 481	l2tp_tunnel_dec_refcount(tunnel);
 482
 483	return genlmsg_unicast(net, msg, info->snd_portid);
 484
 485err_nlmsg_tunnel:
 486	l2tp_tunnel_dec_refcount(tunnel);
 487err_nlmsg:
 488	nlmsg_free(msg);
 489err:
 490	return ret;
 491}
 492
 493static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 494{
 495	int ti = cb->args[0];
 496	struct l2tp_tunnel *tunnel;
 497	struct net *net = sock_net(skb->sk);
 498
 499	for (;;) {
 500		tunnel = l2tp_tunnel_get_nth(net, ti);
 501		if (!tunnel)
 502			goto out;
 503
 504		if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 505					cb->nlh->nlmsg_seq, NLM_F_MULTI,
 506					tunnel, L2TP_CMD_TUNNEL_GET) < 0) {
 507			l2tp_tunnel_dec_refcount(tunnel);
 508			goto out;
 509		}
 510		l2tp_tunnel_dec_refcount(tunnel);
 511
 512		ti++;
 513	}
 514
 515out:
 516	cb->args[0] = ti;
 517
 518	return skb->len;
 519}
 520
 521static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 522{
 523	u32 tunnel_id = 0;
 524	u32 session_id;
 525	u32 peer_session_id;
 526	int ret = 0;
 527	struct l2tp_tunnel *tunnel;
 528	struct l2tp_session *session;
 529	struct l2tp_session_cfg cfg = { 0, };
 530	struct net *net = genl_info_net(info);
 531
 532	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 533		ret = -EINVAL;
 534		goto out;
 535	}
 536
 537	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 538	tunnel = l2tp_tunnel_get(net, tunnel_id);
 539	if (!tunnel) {
 540		ret = -ENODEV;
 541		goto out;
 542	}
 543
 544	if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 545		ret = -EINVAL;
 546		goto out_tunnel;
 547	}
 548	session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 549
 550	if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 551		ret = -EINVAL;
 552		goto out_tunnel;
 553	}
 554	peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 555
 556	if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 557		ret = -EINVAL;
 558		goto out_tunnel;
 559	}
 560	cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 561	if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 562		ret = -EINVAL;
 563		goto out_tunnel;
 564	}
 565
 566	/* L2TPv2 only accepts PPP pseudo-wires */
 567	if (tunnel->version == 2 && cfg.pw_type != L2TP_PWTYPE_PPP) {
 568		ret = -EPROTONOSUPPORT;
 569		goto out_tunnel;
 570	}
 571
 572	if (tunnel->version > 2) {
 573		if (info->attrs[L2TP_ATTR_L2SPEC_TYPE]) {
 574			cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 575			if (cfg.l2specific_type != L2TP_L2SPECTYPE_DEFAULT &&
 576			    cfg.l2specific_type != L2TP_L2SPECTYPE_NONE) {
 577				ret = -EINVAL;
 578				goto out_tunnel;
 579			}
 580		} else {
 581			cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 582		}
 583
 584		if (info->attrs[L2TP_ATTR_COOKIE]) {
 585			u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 586
 587			if (len > 8) {
 588				ret = -EINVAL;
 589				goto out_tunnel;
 590			}
 591			cfg.cookie_len = len;
 592			memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 593		}
 594		if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 595			u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 596
 597			if (len > 8) {
 598				ret = -EINVAL;
 599				goto out_tunnel;
 600			}
 601			cfg.peer_cookie_len = len;
 602			memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 603		}
 604		if (info->attrs[L2TP_ATTR_IFNAME])
 605			cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 606	}
 607
 
 
 
 608	if (info->attrs[L2TP_ATTR_RECV_SEQ])
 609		cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 610
 611	if (info->attrs[L2TP_ATTR_SEND_SEQ])
 612		cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 613
 614	if (info->attrs[L2TP_ATTR_LNS_MODE])
 615		cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 616
 617	if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 618		cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 619
 620#ifdef CONFIG_MODULES
 621	if (!l2tp_nl_cmd_ops[cfg.pw_type]) {
 622		genl_unlock();
 623		request_module("net-l2tp-type-%u", cfg.pw_type);
 624		genl_lock();
 625	}
 626#endif
 627	if (!l2tp_nl_cmd_ops[cfg.pw_type] || !l2tp_nl_cmd_ops[cfg.pw_type]->session_create) {
 628		ret = -EPROTONOSUPPORT;
 629		goto out_tunnel;
 630	}
 631
 632	ret = l2tp_nl_cmd_ops[cfg.pw_type]->session_create(net, tunnel,
 633							   session_id,
 634							   peer_session_id,
 635							   &cfg);
 636
 637	if (ret >= 0) {
 638		session = l2tp_tunnel_get_session(tunnel, session_id);
 639		if (session) {
 640			ret = l2tp_session_notify(&l2tp_nl_family, info, session,
 641						  L2TP_CMD_SESSION_CREATE);
 642			l2tp_session_dec_refcount(session);
 643		}
 644	}
 645
 646out_tunnel:
 647	l2tp_tunnel_dec_refcount(tunnel);
 648out:
 649	return ret;
 650}
 651
 652static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 653{
 654	int ret = 0;
 655	struct l2tp_session *session;
 656	u16 pw_type;
 657
 658	session = l2tp_nl_session_get(info);
 659	if (!session) {
 660		ret = -ENODEV;
 661		goto out;
 662	}
 663
 664	l2tp_session_notify(&l2tp_nl_family, info,
 665			    session, L2TP_CMD_SESSION_DELETE);
 666
 667	pw_type = session->pwtype;
 668	if (pw_type < __L2TP_PWTYPE_MAX)
 669		if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 670			l2tp_nl_cmd_ops[pw_type]->session_delete(session);
 671
 672	l2tp_session_dec_refcount(session);
 673
 674out:
 675	return ret;
 676}
 677
 678static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 679{
 680	int ret = 0;
 681	struct l2tp_session *session;
 682
 683	session = l2tp_nl_session_get(info);
 684	if (!session) {
 685		ret = -ENODEV;
 686		goto out;
 687	}
 688
 
 
 
 689	if (info->attrs[L2TP_ATTR_RECV_SEQ])
 690		session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 691
 692	if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 693		session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 694		l2tp_session_set_header_len(session, session->tunnel->version);
 695	}
 696
 697	if (info->attrs[L2TP_ATTR_LNS_MODE])
 698		session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 699
 700	if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 701		session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 702
 703	ret = l2tp_session_notify(&l2tp_nl_family, info,
 704				  session, L2TP_CMD_SESSION_MODIFY);
 705
 706	l2tp_session_dec_refcount(session);
 707
 708out:
 709	return ret;
 710}
 711
 712static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 713				struct l2tp_session *session, u8 cmd)
 714{
 715	void *hdr;
 716	struct nlattr *nest;
 717	struct l2tp_tunnel *tunnel = session->tunnel;
 718
 719	hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 720	if (!hdr)
 721		return -EMSGSIZE;
 722
 723	if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 724	    nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 725	    nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 726	    nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID, session->peer_session_id) ||
 727	    nla_put_u32(skb, L2TP_ATTR_DEBUG, 0) ||
 728	    nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype))
 729		goto nla_put_failure;
 730
 731	if ((session->ifname[0] &&
 732	     nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 733	    (session->cookie_len &&
 734	     nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len, session->cookie)) ||
 735	    (session->peer_cookie_len &&
 736	     nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len, session->peer_cookie)) ||
 737	    nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 738	    nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 739	    nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 740	    (l2tp_tunnel_uses_xfrm(tunnel) &&
 741	     nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 742	    (session->reorder_timeout &&
 743	     nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT,
 744			   session->reorder_timeout, L2TP_ATTR_PAD)))
 745		goto nla_put_failure;
 746
 747	nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS);
 748	if (!nest)
 749		goto nla_put_failure;
 750
 751	if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
 752			      atomic_long_read(&session->stats.tx_packets),
 753			      L2TP_ATTR_STATS_PAD) ||
 754	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
 755			      atomic_long_read(&session->stats.tx_bytes),
 756			      L2TP_ATTR_STATS_PAD) ||
 757	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
 758			      atomic_long_read(&session->stats.tx_errors),
 759			      L2TP_ATTR_STATS_PAD) ||
 760	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
 761			      atomic_long_read(&session->stats.rx_packets),
 762			      L2TP_ATTR_STATS_PAD) ||
 763	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
 764			      atomic_long_read(&session->stats.rx_bytes),
 765			      L2TP_ATTR_STATS_PAD) ||
 766	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 767			      atomic_long_read(&session->stats.rx_seq_discards),
 768			      L2TP_ATTR_STATS_PAD) ||
 769	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_COOKIE_DISCARDS,
 770			      atomic_long_read(&session->stats.rx_cookie_discards),
 771			      L2TP_ATTR_STATS_PAD) ||
 772	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
 773			      atomic_long_read(&session->stats.rx_oos_packets),
 774			      L2TP_ATTR_STATS_PAD) ||
 775	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
 776			      atomic_long_read(&session->stats.rx_errors),
 777			      L2TP_ATTR_STATS_PAD) ||
 778	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_INVALID,
 779			      atomic_long_read(&session->stats.rx_invalid),
 780			      L2TP_ATTR_STATS_PAD))
 781		goto nla_put_failure;
 782	nla_nest_end(skb, nest);
 783
 784	genlmsg_end(skb, hdr);
 785	return 0;
 786
 787 nla_put_failure:
 788	genlmsg_cancel(skb, hdr);
 789	return -1;
 790}
 791
 792static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 793{
 794	struct l2tp_session *session;
 795	struct sk_buff *msg;
 796	int ret;
 797
 798	session = l2tp_nl_session_get(info);
 799	if (!session) {
 800		ret = -ENODEV;
 801		goto err;
 802	}
 803
 804	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 805	if (!msg) {
 806		ret = -ENOMEM;
 807		goto err_ref;
 808	}
 809
 810	ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 811				   0, session, L2TP_CMD_SESSION_GET);
 812	if (ret < 0)
 813		goto err_ref_msg;
 814
 815	ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 816
 817	l2tp_session_dec_refcount(session);
 818
 819	return ret;
 820
 821err_ref_msg:
 822	nlmsg_free(msg);
 823err_ref:
 824	l2tp_session_dec_refcount(session);
 825err:
 826	return ret;
 827}
 828
 829static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 830{
 831	struct net *net = sock_net(skb->sk);
 832	struct l2tp_session *session;
 833	struct l2tp_tunnel *tunnel = NULL;
 834	int ti = cb->args[0];
 835	int si = cb->args[1];
 836
 837	for (;;) {
 838		if (!tunnel) {
 839			tunnel = l2tp_tunnel_get_nth(net, ti);
 840			if (!tunnel)
 841				goto out;
 842		}
 843
 844		session = l2tp_session_get_nth(tunnel, si);
 845		if (!session) {
 846			ti++;
 847			l2tp_tunnel_dec_refcount(tunnel);
 848			tunnel = NULL;
 849			si = 0;
 850			continue;
 851		}
 852
 853		if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 854					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
 855					 session, L2TP_CMD_SESSION_GET) < 0) {
 856			l2tp_session_dec_refcount(session);
 857			l2tp_tunnel_dec_refcount(tunnel);
 858			break;
 859		}
 860		l2tp_session_dec_refcount(session);
 861
 862		si++;
 863	}
 864
 865out:
 866	cb->args[0] = ti;
 867	cb->args[1] = si;
 868
 869	return skb->len;
 870}
 871
 872static const struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 873	[L2TP_ATTR_NONE]		= { .type = NLA_UNSPEC, },
 874	[L2TP_ATTR_PW_TYPE]		= { .type = NLA_U16, },
 875	[L2TP_ATTR_ENCAP_TYPE]		= { .type = NLA_U16, },
 876	[L2TP_ATTR_OFFSET]		= { .type = NLA_U16, },
 877	[L2TP_ATTR_DATA_SEQ]		= { .type = NLA_U8, },
 878	[L2TP_ATTR_L2SPEC_TYPE]		= { .type = NLA_U8, },
 879	[L2TP_ATTR_L2SPEC_LEN]		= { .type = NLA_U8, },
 880	[L2TP_ATTR_PROTO_VERSION]	= { .type = NLA_U8, },
 881	[L2TP_ATTR_CONN_ID]		= { .type = NLA_U32, },
 882	[L2TP_ATTR_PEER_CONN_ID]	= { .type = NLA_U32, },
 883	[L2TP_ATTR_SESSION_ID]		= { .type = NLA_U32, },
 884	[L2TP_ATTR_PEER_SESSION_ID]	= { .type = NLA_U32, },
 885	[L2TP_ATTR_UDP_CSUM]		= { .type = NLA_U8, },
 886	[L2TP_ATTR_VLAN_ID]		= { .type = NLA_U16, },
 887	[L2TP_ATTR_DEBUG]		= { .type = NLA_U32, },
 888	[L2TP_ATTR_RECV_SEQ]		= { .type = NLA_U8, },
 889	[L2TP_ATTR_SEND_SEQ]		= { .type = NLA_U8, },
 890	[L2TP_ATTR_LNS_MODE]		= { .type = NLA_U8, },
 891	[L2TP_ATTR_USING_IPSEC]		= { .type = NLA_U8, },
 892	[L2TP_ATTR_RECV_TIMEOUT]	= { .type = NLA_MSECS, },
 893	[L2TP_ATTR_FD]			= { .type = NLA_U32, },
 894	[L2TP_ATTR_IP_SADDR]		= { .type = NLA_U32, },
 895	[L2TP_ATTR_IP_DADDR]		= { .type = NLA_U32, },
 896	[L2TP_ATTR_UDP_SPORT]		= { .type = NLA_U16, },
 897	[L2TP_ATTR_UDP_DPORT]		= { .type = NLA_U16, },
 898	[L2TP_ATTR_MTU]			= { .type = NLA_U16, },
 899	[L2TP_ATTR_MRU]			= { .type = NLA_U16, },
 900	[L2TP_ATTR_STATS]		= { .type = NLA_NESTED, },
 901	[L2TP_ATTR_IP6_SADDR] = {
 902		.type = NLA_BINARY,
 903		.len = sizeof(struct in6_addr),
 904	},
 905	[L2TP_ATTR_IP6_DADDR] = {
 906		.type = NLA_BINARY,
 907		.len = sizeof(struct in6_addr),
 908	},
 909	[L2TP_ATTR_IFNAME] = {
 910		.type = NLA_NUL_STRING,
 911		.len = IFNAMSIZ - 1,
 912	},
 913	[L2TP_ATTR_COOKIE] = {
 914		.type = NLA_BINARY,
 915		.len = 8,
 916	},
 917	[L2TP_ATTR_PEER_COOKIE] = {
 918		.type = NLA_BINARY,
 919		.len = 8,
 920	},
 921};
 922
 923static const struct genl_small_ops l2tp_nl_ops[] = {
 924	{
 925		.cmd = L2TP_CMD_NOOP,
 926		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 927		.doit = l2tp_nl_cmd_noop,
 928		/* can be retrieved by unprivileged users */
 929	},
 930	{
 931		.cmd = L2TP_CMD_TUNNEL_CREATE,
 932		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 933		.doit = l2tp_nl_cmd_tunnel_create,
 934		.flags = GENL_UNS_ADMIN_PERM,
 935	},
 936	{
 937		.cmd = L2TP_CMD_TUNNEL_DELETE,
 938		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 939		.doit = l2tp_nl_cmd_tunnel_delete,
 940		.flags = GENL_UNS_ADMIN_PERM,
 941	},
 942	{
 943		.cmd = L2TP_CMD_TUNNEL_MODIFY,
 944		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 945		.doit = l2tp_nl_cmd_tunnel_modify,
 946		.flags = GENL_UNS_ADMIN_PERM,
 947	},
 948	{
 949		.cmd = L2TP_CMD_TUNNEL_GET,
 950		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 951		.doit = l2tp_nl_cmd_tunnel_get,
 952		.dumpit = l2tp_nl_cmd_tunnel_dump,
 953		.flags = GENL_UNS_ADMIN_PERM,
 954	},
 955	{
 956		.cmd = L2TP_CMD_SESSION_CREATE,
 957		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 958		.doit = l2tp_nl_cmd_session_create,
 959		.flags = GENL_UNS_ADMIN_PERM,
 960	},
 961	{
 962		.cmd = L2TP_CMD_SESSION_DELETE,
 963		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 964		.doit = l2tp_nl_cmd_session_delete,
 965		.flags = GENL_UNS_ADMIN_PERM,
 966	},
 967	{
 968		.cmd = L2TP_CMD_SESSION_MODIFY,
 969		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 970		.doit = l2tp_nl_cmd_session_modify,
 971		.flags = GENL_UNS_ADMIN_PERM,
 972	},
 973	{
 974		.cmd = L2TP_CMD_SESSION_GET,
 975		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 976		.doit = l2tp_nl_cmd_session_get,
 977		.dumpit = l2tp_nl_cmd_session_dump,
 978		.flags = GENL_UNS_ADMIN_PERM,
 979	},
 980};
 981
 982static struct genl_family l2tp_nl_family __ro_after_init = {
 983	.name		= L2TP_GENL_NAME,
 984	.version	= L2TP_GENL_VERSION,
 985	.hdrsize	= 0,
 986	.maxattr	= L2TP_ATTR_MAX,
 987	.policy = l2tp_nl_policy,
 988	.netnsok	= true,
 989	.module		= THIS_MODULE,
 990	.small_ops	= l2tp_nl_ops,
 991	.n_small_ops	= ARRAY_SIZE(l2tp_nl_ops),
 992	.resv_start_op	= L2TP_CMD_SESSION_GET + 1,
 993	.mcgrps		= l2tp_multicast_group,
 994	.n_mcgrps	= ARRAY_SIZE(l2tp_multicast_group),
 995};
 996
 997int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 998{
 999	int ret;
1000
1001	ret = -EINVAL;
1002	if (pw_type >= __L2TP_PWTYPE_MAX)
1003		goto err;
1004
1005	genl_lock();
1006	ret = -EBUSY;
1007	if (l2tp_nl_cmd_ops[pw_type])
1008		goto out;
1009
1010	l2tp_nl_cmd_ops[pw_type] = ops;
1011	ret = 0;
1012
1013out:
1014	genl_unlock();
1015err:
1016	return ret;
1017}
1018EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
1019
1020void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
1021{
1022	if (pw_type < __L2TP_PWTYPE_MAX) {
1023		genl_lock();
1024		l2tp_nl_cmd_ops[pw_type] = NULL;
1025		genl_unlock();
1026	}
1027}
1028EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
1029
1030static int __init l2tp_nl_init(void)
1031{
1032	pr_info("L2TP netlink interface\n");
1033	return genl_register_family(&l2tp_nl_family);
1034}
1035
1036static void l2tp_nl_cleanup(void)
1037{
1038	genl_unregister_family(&l2tp_nl_family);
1039}
1040
1041module_init(l2tp_nl_init);
1042module_exit(l2tp_nl_cleanup);
1043
1044MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1045MODULE_DESCRIPTION("L2TP netlink");
1046MODULE_LICENSE("GPL");
1047MODULE_VERSION("1.0");
1048MODULE_ALIAS_GENL_FAMILY("l2tp");
v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   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
  13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15#include <net/sock.h>
  16#include <net/genetlink.h>
  17#include <net/udp.h>
  18#include <linux/in.h>
  19#include <linux/udp.h>
  20#include <linux/socket.h>
  21#include <linux/module.h>
  22#include <linux/list.h>
  23#include <net/net_namespace.h>
  24
  25#include <linux/l2tp.h>
  26
  27#include "l2tp_core.h"
  28
  29static struct genl_family l2tp_nl_family;
  30
  31static const struct genl_multicast_group l2tp_multicast_group[] = {
  32	{
  33		.name = L2TP_GENL_MCGROUP,
  34	},
  35};
  36
  37static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq,
  38			       int flags, struct l2tp_tunnel *tunnel, u8 cmd);
  39static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq,
  40				int flags, struct l2tp_session *session,
  41				u8 cmd);
  42
  43/* Accessed under genl lock */
  44static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
  45
  46static struct l2tp_session *l2tp_nl_session_get(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_get_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_get(net, tunnel_id);
  63		if (tunnel) {
  64			session = l2tp_tunnel_get_session(tunnel, session_id);
  65			l2tp_tunnel_dec_refcount(tunnel);
  66		}
  67	}
  68
  69	return session;
  70}
  71
  72static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
  73{
  74	struct sk_buff *msg;
  75	void *hdr;
  76	int ret = -ENOBUFS;
  77
  78	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  79	if (!msg) {
  80		ret = -ENOMEM;
  81		goto out;
  82	}
  83
  84	hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
  85			  &l2tp_nl_family, 0, L2TP_CMD_NOOP);
  86	if (!hdr) {
  87		ret = -EMSGSIZE;
  88		goto err_out;
  89	}
  90
  91	genlmsg_end(msg, hdr);
  92
  93	return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
  94
  95err_out:
  96	nlmsg_free(msg);
  97
  98out:
  99	return ret;
 100}
 101
 102static int l2tp_tunnel_notify(struct genl_family *family,
 103			      struct genl_info *info,
 104			      struct l2tp_tunnel *tunnel,
 105			      u8 cmd)
 106{
 107	struct sk_buff *msg;
 108	int ret;
 109
 110	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 111	if (!msg)
 112		return -ENOMEM;
 113
 114	ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 115				  NLM_F_ACK, tunnel, cmd);
 116
 117	if (ret >= 0) {
 118		ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
 119		/* We don't care if no one is listening */
 120		if (ret == -ESRCH)
 121			ret = 0;
 122		return ret;
 123	}
 124
 125	nlmsg_free(msg);
 126
 127	return ret;
 128}
 129
 130static int l2tp_session_notify(struct genl_family *family,
 131			       struct genl_info *info,
 132			       struct l2tp_session *session,
 133			       u8 cmd)
 134{
 135	struct sk_buff *msg;
 136	int ret;
 137
 138	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 139	if (!msg)
 140		return -ENOMEM;
 141
 142	ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 143				   NLM_F_ACK, session, cmd);
 144
 145	if (ret >= 0) {
 146		ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC);
 147		/* We don't care if no one is listening */
 148		if (ret == -ESRCH)
 149			ret = 0;
 150		return ret;
 151	}
 152
 153	nlmsg_free(msg);
 154
 155	return ret;
 156}
 157
 158static int l2tp_nl_cmd_tunnel_create_get_addr(struct nlattr **attrs, struct l2tp_tunnel_cfg *cfg)
 159{
 160	if (attrs[L2TP_ATTR_UDP_SPORT])
 161		cfg->local_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_SPORT]);
 162	if (attrs[L2TP_ATTR_UDP_DPORT])
 163		cfg->peer_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_DPORT]);
 164	cfg->use_udp_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_CSUM]);
 165
 166	/* Must have either AF_INET or AF_INET6 address for source and destination */
 167#if IS_ENABLED(CONFIG_IPV6)
 168	if (attrs[L2TP_ATTR_IP6_SADDR] && attrs[L2TP_ATTR_IP6_DADDR]) {
 169		cfg->local_ip6 = nla_data(attrs[L2TP_ATTR_IP6_SADDR]);
 170		cfg->peer_ip6 = nla_data(attrs[L2TP_ATTR_IP6_DADDR]);
 171		cfg->udp6_zero_tx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
 172		cfg->udp6_zero_rx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
 173		return 0;
 174	}
 175#endif
 176	if (attrs[L2TP_ATTR_IP_SADDR] && attrs[L2TP_ATTR_IP_DADDR]) {
 177		cfg->local_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_SADDR]);
 178		cfg->peer_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_DADDR]);
 179		return 0;
 180	}
 181	return -EINVAL;
 182}
 183
 184static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
 185{
 186	u32 tunnel_id;
 187	u32 peer_tunnel_id;
 188	int proto_version;
 189	int fd = -1;
 190	int ret = 0;
 191	struct l2tp_tunnel_cfg cfg = { 0, };
 192	struct l2tp_tunnel *tunnel;
 193	struct net *net = genl_info_net(info);
 194	struct nlattr **attrs = info->attrs;
 195
 196	if (!attrs[L2TP_ATTR_CONN_ID]) {
 197		ret = -EINVAL;
 198		goto out;
 199	}
 200	tunnel_id = nla_get_u32(attrs[L2TP_ATTR_CONN_ID]);
 201
 202	if (!attrs[L2TP_ATTR_PEER_CONN_ID]) {
 203		ret = -EINVAL;
 204		goto out;
 205	}
 206	peer_tunnel_id = nla_get_u32(attrs[L2TP_ATTR_PEER_CONN_ID]);
 207
 208	if (!attrs[L2TP_ATTR_PROTO_VERSION]) {
 209		ret = -EINVAL;
 210		goto out;
 211	}
 212	proto_version = nla_get_u8(attrs[L2TP_ATTR_PROTO_VERSION]);
 213
 214	if (!attrs[L2TP_ATTR_ENCAP_TYPE]) {
 215		ret = -EINVAL;
 216		goto out;
 217	}
 218	cfg.encap = nla_get_u16(attrs[L2TP_ATTR_ENCAP_TYPE]);
 219
 220	/* Managed tunnels take the tunnel socket from userspace.
 221	 * Unmanaged tunnels must call out the source and destination addresses
 222	 * for the kernel to create the tunnel socket itself.
 223	 */
 224	if (attrs[L2TP_ATTR_FD]) {
 225		fd = nla_get_u32(attrs[L2TP_ATTR_FD]);
 226	} else {
 227		ret = l2tp_nl_cmd_tunnel_create_get_addr(attrs, &cfg);
 228		if (ret < 0)
 229			goto out;
 230	}
 231
 232	if (attrs[L2TP_ATTR_DEBUG])
 233		cfg.debug = nla_get_u32(attrs[L2TP_ATTR_DEBUG]);
 234
 235	ret = -EINVAL;
 236	switch (cfg.encap) {
 237	case L2TP_ENCAPTYPE_UDP:
 238	case L2TP_ENCAPTYPE_IP:
 239		ret = l2tp_tunnel_create(net, fd, proto_version, tunnel_id,
 240					 peer_tunnel_id, &cfg, &tunnel);
 241		break;
 242	}
 243
 244	if (ret < 0)
 245		goto out;
 246
 247	l2tp_tunnel_inc_refcount(tunnel);
 248	ret = l2tp_tunnel_register(tunnel, net, &cfg);
 249	if (ret < 0) {
 250		kfree(tunnel);
 251		goto out;
 252	}
 253	ret = l2tp_tunnel_notify(&l2tp_nl_family, info, tunnel,
 254				 L2TP_CMD_TUNNEL_CREATE);
 255	l2tp_tunnel_dec_refcount(tunnel);
 256
 257out:
 258	return ret;
 259}
 260
 261static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 262{
 263	struct l2tp_tunnel *tunnel;
 264	u32 tunnel_id;
 265	int ret = 0;
 266	struct net *net = genl_info_net(info);
 267
 268	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 269		ret = -EINVAL;
 270		goto out;
 271	}
 272	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 273
 274	tunnel = l2tp_tunnel_get(net, tunnel_id);
 275	if (!tunnel) {
 276		ret = -ENODEV;
 277		goto out;
 278	}
 279
 280	l2tp_tunnel_notify(&l2tp_nl_family, info,
 281			   tunnel, L2TP_CMD_TUNNEL_DELETE);
 282
 283	l2tp_tunnel_delete(tunnel);
 284
 285	l2tp_tunnel_dec_refcount(tunnel);
 286
 287out:
 288	return ret;
 289}
 290
 291static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 292{
 293	struct l2tp_tunnel *tunnel;
 294	u32 tunnel_id;
 295	int ret = 0;
 296	struct net *net = genl_info_net(info);
 297
 298	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 299		ret = -EINVAL;
 300		goto out;
 301	}
 302	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 303
 304	tunnel = l2tp_tunnel_get(net, tunnel_id);
 305	if (!tunnel) {
 306		ret = -ENODEV;
 307		goto out;
 308	}
 309
 310	if (info->attrs[L2TP_ATTR_DEBUG])
 311		tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 312
 313	ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 314				 tunnel, L2TP_CMD_TUNNEL_MODIFY);
 315
 316	l2tp_tunnel_dec_refcount(tunnel);
 317
 318out:
 319	return ret;
 320}
 321
 322#if IS_ENABLED(CONFIG_IPV6)
 323static int l2tp_nl_tunnel_send_addr6(struct sk_buff *skb, struct sock *sk,
 324				     enum l2tp_encap_type encap)
 325{
 326	struct inet_sock *inet = inet_sk(sk);
 327	struct ipv6_pinfo *np = inet6_sk(sk);
 328
 329	switch (encap) {
 330	case L2TP_ENCAPTYPE_UDP:
 331		if (udp_get_no_check6_tx(sk) &&
 332		    nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_TX))
 333			return -1;
 334		if (udp_get_no_check6_rx(sk) &&
 335		    nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_RX))
 336			return -1;
 337		if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 338		    nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
 339			return -1;
 340		fallthrough;
 341	case L2TP_ENCAPTYPE_IP:
 342		if (nla_put_in6_addr(skb, L2TP_ATTR_IP6_SADDR, &np->saddr) ||
 343		    nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR, &sk->sk_v6_daddr))
 344			return -1;
 345		break;
 346	}
 347	return 0;
 348}
 349#endif
 350
 351static int l2tp_nl_tunnel_send_addr4(struct sk_buff *skb, struct sock *sk,
 352				     enum l2tp_encap_type encap)
 353{
 354	struct inet_sock *inet = inet_sk(sk);
 355
 356	switch (encap) {
 357	case L2TP_ENCAPTYPE_UDP:
 358		if (nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx) ||
 359		    nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 360		    nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
 361			return -1;
 362		fallthrough;
 363	case L2TP_ENCAPTYPE_IP:
 364		if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 365		    nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 366			return -1;
 367		break;
 368	}
 369
 370	return 0;
 371}
 372
 373/* Append attributes for the tunnel address, handling the different attribute types
 374 * used for different tunnel encapsulation and AF_INET v.s. AF_INET6.
 375 */
 376static int l2tp_nl_tunnel_send_addr(struct sk_buff *skb, struct l2tp_tunnel *tunnel)
 377{
 378	struct sock *sk = tunnel->sock;
 379
 380	if (!sk)
 381		return 0;
 382
 383#if IS_ENABLED(CONFIG_IPV6)
 384	if (sk->sk_family == AF_INET6)
 385		return l2tp_nl_tunnel_send_addr6(skb, sk, tunnel->encap);
 386#endif
 387	return l2tp_nl_tunnel_send_addr4(skb, sk, tunnel->encap);
 388}
 389
 390static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 391			       struct l2tp_tunnel *tunnel, u8 cmd)
 392{
 393	void *hdr;
 394	struct nlattr *nest;
 395
 396	hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 397	if (!hdr)
 398		return -EMSGSIZE;
 399
 400	if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 401	    nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 402	    nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 403	    nla_put_u32(skb, L2TP_ATTR_DEBUG, tunnel->debug) ||
 404	    nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 405		goto nla_put_failure;
 406
 407	nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS);
 408	if (!nest)
 409		goto nla_put_failure;
 410
 411	if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
 412			      atomic_long_read(&tunnel->stats.tx_packets),
 413			      L2TP_ATTR_STATS_PAD) ||
 414	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
 415			      atomic_long_read(&tunnel->stats.tx_bytes),
 416			      L2TP_ATTR_STATS_PAD) ||
 417	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
 418			      atomic_long_read(&tunnel->stats.tx_errors),
 419			      L2TP_ATTR_STATS_PAD) ||
 420	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
 421			      atomic_long_read(&tunnel->stats.rx_packets),
 422			      L2TP_ATTR_STATS_PAD) ||
 423	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
 424			      atomic_long_read(&tunnel->stats.rx_bytes),
 425			      L2TP_ATTR_STATS_PAD) ||
 426	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 427			      atomic_long_read(&tunnel->stats.rx_seq_discards),
 428			      L2TP_ATTR_STATS_PAD) ||
 
 
 
 429	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
 430			      atomic_long_read(&tunnel->stats.rx_oos_packets),
 431			      L2TP_ATTR_STATS_PAD) ||
 432	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
 433			      atomic_long_read(&tunnel->stats.rx_errors),
 
 
 
 434			      L2TP_ATTR_STATS_PAD))
 435		goto nla_put_failure;
 436	nla_nest_end(skb, nest);
 437
 438	if (l2tp_nl_tunnel_send_addr(skb, tunnel))
 439		goto nla_put_failure;
 440
 441	genlmsg_end(skb, hdr);
 442	return 0;
 443
 444nla_put_failure:
 445	genlmsg_cancel(skb, hdr);
 446	return -1;
 447}
 448
 449static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 450{
 451	struct l2tp_tunnel *tunnel;
 452	struct sk_buff *msg;
 453	u32 tunnel_id;
 454	int ret = -ENOBUFS;
 455	struct net *net = genl_info_net(info);
 456
 457	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 458		ret = -EINVAL;
 459		goto err;
 460	}
 461
 462	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 463
 464	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 465	if (!msg) {
 466		ret = -ENOMEM;
 467		goto err;
 468	}
 469
 470	tunnel = l2tp_tunnel_get(net, tunnel_id);
 471	if (!tunnel) {
 472		ret = -ENODEV;
 473		goto err_nlmsg;
 474	}
 475
 476	ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 477				  NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
 478	if (ret < 0)
 479		goto err_nlmsg_tunnel;
 480
 481	l2tp_tunnel_dec_refcount(tunnel);
 482
 483	return genlmsg_unicast(net, msg, info->snd_portid);
 484
 485err_nlmsg_tunnel:
 486	l2tp_tunnel_dec_refcount(tunnel);
 487err_nlmsg:
 488	nlmsg_free(msg);
 489err:
 490	return ret;
 491}
 492
 493static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 494{
 495	int ti = cb->args[0];
 496	struct l2tp_tunnel *tunnel;
 497	struct net *net = sock_net(skb->sk);
 498
 499	for (;;) {
 500		tunnel = l2tp_tunnel_get_nth(net, ti);
 501		if (!tunnel)
 502			goto out;
 503
 504		if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 505					cb->nlh->nlmsg_seq, NLM_F_MULTI,
 506					tunnel, L2TP_CMD_TUNNEL_GET) < 0) {
 507			l2tp_tunnel_dec_refcount(tunnel);
 508			goto out;
 509		}
 510		l2tp_tunnel_dec_refcount(tunnel);
 511
 512		ti++;
 513	}
 514
 515out:
 516	cb->args[0] = ti;
 517
 518	return skb->len;
 519}
 520
 521static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 522{
 523	u32 tunnel_id = 0;
 524	u32 session_id;
 525	u32 peer_session_id;
 526	int ret = 0;
 527	struct l2tp_tunnel *tunnel;
 528	struct l2tp_session *session;
 529	struct l2tp_session_cfg cfg = { 0, };
 530	struct net *net = genl_info_net(info);
 531
 532	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 533		ret = -EINVAL;
 534		goto out;
 535	}
 536
 537	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 538	tunnel = l2tp_tunnel_get(net, tunnel_id);
 539	if (!tunnel) {
 540		ret = -ENODEV;
 541		goto out;
 542	}
 543
 544	if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 545		ret = -EINVAL;
 546		goto out_tunnel;
 547	}
 548	session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 549
 550	if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 551		ret = -EINVAL;
 552		goto out_tunnel;
 553	}
 554	peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 555
 556	if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 557		ret = -EINVAL;
 558		goto out_tunnel;
 559	}
 560	cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 561	if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 562		ret = -EINVAL;
 563		goto out_tunnel;
 564	}
 565
 566	/* L2TPv2 only accepts PPP pseudo-wires */
 567	if (tunnel->version == 2 && cfg.pw_type != L2TP_PWTYPE_PPP) {
 568		ret = -EPROTONOSUPPORT;
 569		goto out_tunnel;
 570	}
 571
 572	if (tunnel->version > 2) {
 573		if (info->attrs[L2TP_ATTR_L2SPEC_TYPE]) {
 574			cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 575			if (cfg.l2specific_type != L2TP_L2SPECTYPE_DEFAULT &&
 576			    cfg.l2specific_type != L2TP_L2SPECTYPE_NONE) {
 577				ret = -EINVAL;
 578				goto out_tunnel;
 579			}
 580		} else {
 581			cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 582		}
 583
 584		if (info->attrs[L2TP_ATTR_COOKIE]) {
 585			u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 586
 587			if (len > 8) {
 588				ret = -EINVAL;
 589				goto out_tunnel;
 590			}
 591			cfg.cookie_len = len;
 592			memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 593		}
 594		if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 595			u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 596
 597			if (len > 8) {
 598				ret = -EINVAL;
 599				goto out_tunnel;
 600			}
 601			cfg.peer_cookie_len = len;
 602			memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 603		}
 604		if (info->attrs[L2TP_ATTR_IFNAME])
 605			cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 606	}
 607
 608	if (info->attrs[L2TP_ATTR_DEBUG])
 609		cfg.debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 610
 611	if (info->attrs[L2TP_ATTR_RECV_SEQ])
 612		cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 613
 614	if (info->attrs[L2TP_ATTR_SEND_SEQ])
 615		cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 616
 617	if (info->attrs[L2TP_ATTR_LNS_MODE])
 618		cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 619
 620	if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 621		cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 622
 623#ifdef CONFIG_MODULES
 624	if (!l2tp_nl_cmd_ops[cfg.pw_type]) {
 625		genl_unlock();
 626		request_module("net-l2tp-type-%u", cfg.pw_type);
 627		genl_lock();
 628	}
 629#endif
 630	if (!l2tp_nl_cmd_ops[cfg.pw_type] || !l2tp_nl_cmd_ops[cfg.pw_type]->session_create) {
 631		ret = -EPROTONOSUPPORT;
 632		goto out_tunnel;
 633	}
 634
 635	ret = l2tp_nl_cmd_ops[cfg.pw_type]->session_create(net, tunnel,
 636							   session_id,
 637							   peer_session_id,
 638							   &cfg);
 639
 640	if (ret >= 0) {
 641		session = l2tp_tunnel_get_session(tunnel, session_id);
 642		if (session) {
 643			ret = l2tp_session_notify(&l2tp_nl_family, info, session,
 644						  L2TP_CMD_SESSION_CREATE);
 645			l2tp_session_dec_refcount(session);
 646		}
 647	}
 648
 649out_tunnel:
 650	l2tp_tunnel_dec_refcount(tunnel);
 651out:
 652	return ret;
 653}
 654
 655static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 656{
 657	int ret = 0;
 658	struct l2tp_session *session;
 659	u16 pw_type;
 660
 661	session = l2tp_nl_session_get(info);
 662	if (!session) {
 663		ret = -ENODEV;
 664		goto out;
 665	}
 666
 667	l2tp_session_notify(&l2tp_nl_family, info,
 668			    session, L2TP_CMD_SESSION_DELETE);
 669
 670	pw_type = session->pwtype;
 671	if (pw_type < __L2TP_PWTYPE_MAX)
 672		if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 673			l2tp_nl_cmd_ops[pw_type]->session_delete(session);
 674
 675	l2tp_session_dec_refcount(session);
 676
 677out:
 678	return ret;
 679}
 680
 681static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 682{
 683	int ret = 0;
 684	struct l2tp_session *session;
 685
 686	session = l2tp_nl_session_get(info);
 687	if (!session) {
 688		ret = -ENODEV;
 689		goto out;
 690	}
 691
 692	if (info->attrs[L2TP_ATTR_DEBUG])
 693		session->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]);
 694
 695	if (info->attrs[L2TP_ATTR_RECV_SEQ])
 696		session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 697
 698	if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 699		session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 700		l2tp_session_set_header_len(session, session->tunnel->version);
 701	}
 702
 703	if (info->attrs[L2TP_ATTR_LNS_MODE])
 704		session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 705
 706	if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 707		session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 708
 709	ret = l2tp_session_notify(&l2tp_nl_family, info,
 710				  session, L2TP_CMD_SESSION_MODIFY);
 711
 712	l2tp_session_dec_refcount(session);
 713
 714out:
 715	return ret;
 716}
 717
 718static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 719				struct l2tp_session *session, u8 cmd)
 720{
 721	void *hdr;
 722	struct nlattr *nest;
 723	struct l2tp_tunnel *tunnel = session->tunnel;
 724
 725	hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 726	if (!hdr)
 727		return -EMSGSIZE;
 728
 729	if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 730	    nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 731	    nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 732	    nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID, session->peer_session_id) ||
 733	    nla_put_u32(skb, L2TP_ATTR_DEBUG, session->debug) ||
 734	    nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype))
 735		goto nla_put_failure;
 736
 737	if ((session->ifname[0] &&
 738	     nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 739	    (session->cookie_len &&
 740	     nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len, session->cookie)) ||
 741	    (session->peer_cookie_len &&
 742	     nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len, session->peer_cookie)) ||
 743	    nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 744	    nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 745	    nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 746	    (l2tp_tunnel_uses_xfrm(tunnel) &&
 747	     nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 748	    (session->reorder_timeout &&
 749	     nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT,
 750			   session->reorder_timeout, L2TP_ATTR_PAD)))
 751		goto nla_put_failure;
 752
 753	nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS);
 754	if (!nest)
 755		goto nla_put_failure;
 756
 757	if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
 758			      atomic_long_read(&session->stats.tx_packets),
 759			      L2TP_ATTR_STATS_PAD) ||
 760	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
 761			      atomic_long_read(&session->stats.tx_bytes),
 762			      L2TP_ATTR_STATS_PAD) ||
 763	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
 764			      atomic_long_read(&session->stats.tx_errors),
 765			      L2TP_ATTR_STATS_PAD) ||
 766	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
 767			      atomic_long_read(&session->stats.rx_packets),
 768			      L2TP_ATTR_STATS_PAD) ||
 769	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
 770			      atomic_long_read(&session->stats.rx_bytes),
 771			      L2TP_ATTR_STATS_PAD) ||
 772	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 773			      atomic_long_read(&session->stats.rx_seq_discards),
 774			      L2TP_ATTR_STATS_PAD) ||
 
 
 
 775	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
 776			      atomic_long_read(&session->stats.rx_oos_packets),
 777			      L2TP_ATTR_STATS_PAD) ||
 778	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
 779			      atomic_long_read(&session->stats.rx_errors),
 
 
 
 780			      L2TP_ATTR_STATS_PAD))
 781		goto nla_put_failure;
 782	nla_nest_end(skb, nest);
 783
 784	genlmsg_end(skb, hdr);
 785	return 0;
 786
 787 nla_put_failure:
 788	genlmsg_cancel(skb, hdr);
 789	return -1;
 790}
 791
 792static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 793{
 794	struct l2tp_session *session;
 795	struct sk_buff *msg;
 796	int ret;
 797
 798	session = l2tp_nl_session_get(info);
 799	if (!session) {
 800		ret = -ENODEV;
 801		goto err;
 802	}
 803
 804	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 805	if (!msg) {
 806		ret = -ENOMEM;
 807		goto err_ref;
 808	}
 809
 810	ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 811				   0, session, L2TP_CMD_SESSION_GET);
 812	if (ret < 0)
 813		goto err_ref_msg;
 814
 815	ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 816
 817	l2tp_session_dec_refcount(session);
 818
 819	return ret;
 820
 821err_ref_msg:
 822	nlmsg_free(msg);
 823err_ref:
 824	l2tp_session_dec_refcount(session);
 825err:
 826	return ret;
 827}
 828
 829static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 830{
 831	struct net *net = sock_net(skb->sk);
 832	struct l2tp_session *session;
 833	struct l2tp_tunnel *tunnel = NULL;
 834	int ti = cb->args[0];
 835	int si = cb->args[1];
 836
 837	for (;;) {
 838		if (!tunnel) {
 839			tunnel = l2tp_tunnel_get_nth(net, ti);
 840			if (!tunnel)
 841				goto out;
 842		}
 843
 844		session = l2tp_session_get_nth(tunnel, si);
 845		if (!session) {
 846			ti++;
 847			l2tp_tunnel_dec_refcount(tunnel);
 848			tunnel = NULL;
 849			si = 0;
 850			continue;
 851		}
 852
 853		if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 854					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
 855					 session, L2TP_CMD_SESSION_GET) < 0) {
 856			l2tp_session_dec_refcount(session);
 857			l2tp_tunnel_dec_refcount(tunnel);
 858			break;
 859		}
 860		l2tp_session_dec_refcount(session);
 861
 862		si++;
 863	}
 864
 865out:
 866	cb->args[0] = ti;
 867	cb->args[1] = si;
 868
 869	return skb->len;
 870}
 871
 872static const struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 873	[L2TP_ATTR_NONE]		= { .type = NLA_UNSPEC, },
 874	[L2TP_ATTR_PW_TYPE]		= { .type = NLA_U16, },
 875	[L2TP_ATTR_ENCAP_TYPE]		= { .type = NLA_U16, },
 876	[L2TP_ATTR_OFFSET]		= { .type = NLA_U16, },
 877	[L2TP_ATTR_DATA_SEQ]		= { .type = NLA_U8, },
 878	[L2TP_ATTR_L2SPEC_TYPE]		= { .type = NLA_U8, },
 879	[L2TP_ATTR_L2SPEC_LEN]		= { .type = NLA_U8, },
 880	[L2TP_ATTR_PROTO_VERSION]	= { .type = NLA_U8, },
 881	[L2TP_ATTR_CONN_ID]		= { .type = NLA_U32, },
 882	[L2TP_ATTR_PEER_CONN_ID]	= { .type = NLA_U32, },
 883	[L2TP_ATTR_SESSION_ID]		= { .type = NLA_U32, },
 884	[L2TP_ATTR_PEER_SESSION_ID]	= { .type = NLA_U32, },
 885	[L2TP_ATTR_UDP_CSUM]		= { .type = NLA_U8, },
 886	[L2TP_ATTR_VLAN_ID]		= { .type = NLA_U16, },
 887	[L2TP_ATTR_DEBUG]		= { .type = NLA_U32, },
 888	[L2TP_ATTR_RECV_SEQ]		= { .type = NLA_U8, },
 889	[L2TP_ATTR_SEND_SEQ]		= { .type = NLA_U8, },
 890	[L2TP_ATTR_LNS_MODE]		= { .type = NLA_U8, },
 891	[L2TP_ATTR_USING_IPSEC]		= { .type = NLA_U8, },
 892	[L2TP_ATTR_RECV_TIMEOUT]	= { .type = NLA_MSECS, },
 893	[L2TP_ATTR_FD]			= { .type = NLA_U32, },
 894	[L2TP_ATTR_IP_SADDR]		= { .type = NLA_U32, },
 895	[L2TP_ATTR_IP_DADDR]		= { .type = NLA_U32, },
 896	[L2TP_ATTR_UDP_SPORT]		= { .type = NLA_U16, },
 897	[L2TP_ATTR_UDP_DPORT]		= { .type = NLA_U16, },
 898	[L2TP_ATTR_MTU]			= { .type = NLA_U16, },
 899	[L2TP_ATTR_MRU]			= { .type = NLA_U16, },
 900	[L2TP_ATTR_STATS]		= { .type = NLA_NESTED, },
 901	[L2TP_ATTR_IP6_SADDR] = {
 902		.type = NLA_BINARY,
 903		.len = sizeof(struct in6_addr),
 904	},
 905	[L2TP_ATTR_IP6_DADDR] = {
 906		.type = NLA_BINARY,
 907		.len = sizeof(struct in6_addr),
 908	},
 909	[L2TP_ATTR_IFNAME] = {
 910		.type = NLA_NUL_STRING,
 911		.len = IFNAMSIZ - 1,
 912	},
 913	[L2TP_ATTR_COOKIE] = {
 914		.type = NLA_BINARY,
 915		.len = 8,
 916	},
 917	[L2TP_ATTR_PEER_COOKIE] = {
 918		.type = NLA_BINARY,
 919		.len = 8,
 920	},
 921};
 922
 923static const struct genl_ops l2tp_nl_ops[] = {
 924	{
 925		.cmd = L2TP_CMD_NOOP,
 926		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 927		.doit = l2tp_nl_cmd_noop,
 928		/* can be retrieved by unprivileged users */
 929	},
 930	{
 931		.cmd = L2TP_CMD_TUNNEL_CREATE,
 932		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 933		.doit = l2tp_nl_cmd_tunnel_create,
 934		.flags = GENL_UNS_ADMIN_PERM,
 935	},
 936	{
 937		.cmd = L2TP_CMD_TUNNEL_DELETE,
 938		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 939		.doit = l2tp_nl_cmd_tunnel_delete,
 940		.flags = GENL_UNS_ADMIN_PERM,
 941	},
 942	{
 943		.cmd = L2TP_CMD_TUNNEL_MODIFY,
 944		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 945		.doit = l2tp_nl_cmd_tunnel_modify,
 946		.flags = GENL_UNS_ADMIN_PERM,
 947	},
 948	{
 949		.cmd = L2TP_CMD_TUNNEL_GET,
 950		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 951		.doit = l2tp_nl_cmd_tunnel_get,
 952		.dumpit = l2tp_nl_cmd_tunnel_dump,
 953		.flags = GENL_UNS_ADMIN_PERM,
 954	},
 955	{
 956		.cmd = L2TP_CMD_SESSION_CREATE,
 957		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 958		.doit = l2tp_nl_cmd_session_create,
 959		.flags = GENL_UNS_ADMIN_PERM,
 960	},
 961	{
 962		.cmd = L2TP_CMD_SESSION_DELETE,
 963		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 964		.doit = l2tp_nl_cmd_session_delete,
 965		.flags = GENL_UNS_ADMIN_PERM,
 966	},
 967	{
 968		.cmd = L2TP_CMD_SESSION_MODIFY,
 969		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 970		.doit = l2tp_nl_cmd_session_modify,
 971		.flags = GENL_UNS_ADMIN_PERM,
 972	},
 973	{
 974		.cmd = L2TP_CMD_SESSION_GET,
 975		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 976		.doit = l2tp_nl_cmd_session_get,
 977		.dumpit = l2tp_nl_cmd_session_dump,
 978		.flags = GENL_UNS_ADMIN_PERM,
 979	},
 980};
 981
 982static struct genl_family l2tp_nl_family __ro_after_init = {
 983	.name		= L2TP_GENL_NAME,
 984	.version	= L2TP_GENL_VERSION,
 985	.hdrsize	= 0,
 986	.maxattr	= L2TP_ATTR_MAX,
 987	.policy = l2tp_nl_policy,
 988	.netnsok	= true,
 989	.module		= THIS_MODULE,
 990	.ops		= l2tp_nl_ops,
 991	.n_ops		= ARRAY_SIZE(l2tp_nl_ops),
 
 992	.mcgrps		= l2tp_multicast_group,
 993	.n_mcgrps	= ARRAY_SIZE(l2tp_multicast_group),
 994};
 995
 996int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
 997{
 998	int ret;
 999
1000	ret = -EINVAL;
1001	if (pw_type >= __L2TP_PWTYPE_MAX)
1002		goto err;
1003
1004	genl_lock();
1005	ret = -EBUSY;
1006	if (l2tp_nl_cmd_ops[pw_type])
1007		goto out;
1008
1009	l2tp_nl_cmd_ops[pw_type] = ops;
1010	ret = 0;
1011
1012out:
1013	genl_unlock();
1014err:
1015	return ret;
1016}
1017EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
1018
1019void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
1020{
1021	if (pw_type < __L2TP_PWTYPE_MAX) {
1022		genl_lock();
1023		l2tp_nl_cmd_ops[pw_type] = NULL;
1024		genl_unlock();
1025	}
1026}
1027EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
1028
1029static int __init l2tp_nl_init(void)
1030{
1031	pr_info("L2TP netlink interface\n");
1032	return genl_register_family(&l2tp_nl_family);
1033}
1034
1035static void l2tp_nl_cleanup(void)
1036{
1037	genl_unregister_family(&l2tp_nl_family);
1038}
1039
1040module_init(l2tp_nl_init);
1041module_exit(l2tp_nl_cleanup);
1042
1043MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1044MODULE_DESCRIPTION("L2TP netlink");
1045MODULE_LICENSE("GPL");
1046MODULE_VERSION("1.0");
1047MODULE_ALIAS_GENL_FAMILY("l2tp");