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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");
v6.13.7
   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_session_get(net, tunnel->sock, tunnel->version,
  65						   tunnel_id, session_id);
  66			l2tp_tunnel_put(tunnel);
  67		}
  68	}
  69
  70	return session;
  71}
  72
  73static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info)
  74{
  75	struct sk_buff *msg;
  76	void *hdr;
  77	int ret = -ENOBUFS;
  78
  79	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  80	if (!msg) {
  81		ret = -ENOMEM;
  82		goto out;
  83	}
  84
  85	hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
  86			  &l2tp_nl_family, 0, L2TP_CMD_NOOP);
  87	if (!hdr) {
  88		ret = -EMSGSIZE;
  89		goto err_out;
  90	}
  91
  92	genlmsg_end(msg, hdr);
  93
  94	return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
  95
  96err_out:
  97	nlmsg_free(msg);
  98
  99out:
 100	return ret;
 101}
 102
 103static int l2tp_tunnel_notify(struct genl_family *family,
 104			      struct genl_info *info,
 105			      struct l2tp_tunnel *tunnel,
 106			      u8 cmd)
 107{
 108	struct sk_buff *msg;
 109	int ret;
 110
 111	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 112	if (!msg)
 113		return -ENOMEM;
 114
 115	ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 116				  NLM_F_ACK, tunnel, cmd);
 117
 118	if (ret >= 0) {
 119		ret = genlmsg_multicast_allns(family, msg, 0, 0);
 120		/* We don't care if no one is listening */
 121		if (ret == -ESRCH)
 122			ret = 0;
 123		return ret;
 124	}
 125
 126	nlmsg_free(msg);
 127
 128	return ret;
 129}
 130
 131static int l2tp_session_notify(struct genl_family *family,
 132			       struct genl_info *info,
 133			       struct l2tp_session *session,
 134			       u8 cmd)
 135{
 136	struct sk_buff *msg;
 137	int ret;
 138
 139	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 140	if (!msg)
 141		return -ENOMEM;
 142
 143	ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 144				   NLM_F_ACK, session, cmd);
 145
 146	if (ret >= 0) {
 147		ret = genlmsg_multicast_allns(family, msg, 0, 0);
 148		/* We don't care if no one is listening */
 149		if (ret == -ESRCH)
 150			ret = 0;
 151		return ret;
 152	}
 153
 154	nlmsg_free(msg);
 155
 156	return ret;
 157}
 158
 159static int l2tp_nl_cmd_tunnel_create_get_addr(struct nlattr **attrs, struct l2tp_tunnel_cfg *cfg)
 160{
 161	if (attrs[L2TP_ATTR_UDP_SPORT])
 162		cfg->local_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_SPORT]);
 163	if (attrs[L2TP_ATTR_UDP_DPORT])
 164		cfg->peer_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_DPORT]);
 165	cfg->use_udp_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_CSUM]);
 166
 167	/* Must have either AF_INET or AF_INET6 address for source and destination */
 168#if IS_ENABLED(CONFIG_IPV6)
 169	if (attrs[L2TP_ATTR_IP6_SADDR] && attrs[L2TP_ATTR_IP6_DADDR]) {
 170		cfg->local_ip6 = nla_data(attrs[L2TP_ATTR_IP6_SADDR]);
 171		cfg->peer_ip6 = nla_data(attrs[L2TP_ATTR_IP6_DADDR]);
 172		cfg->udp6_zero_tx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]);
 173		cfg->udp6_zero_rx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]);
 174		return 0;
 175	}
 176#endif
 177	if (attrs[L2TP_ATTR_IP_SADDR] && attrs[L2TP_ATTR_IP_DADDR]) {
 178		cfg->local_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_SADDR]);
 179		cfg->peer_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_DADDR]);
 180		return 0;
 181	}
 182	return -EINVAL;
 183}
 184
 185static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info)
 186{
 187	u32 tunnel_id;
 188	u32 peer_tunnel_id;
 189	int proto_version;
 190	int fd = -1;
 191	int ret = 0;
 192	struct l2tp_tunnel_cfg cfg = { 0, };
 193	struct l2tp_tunnel *tunnel;
 194	struct net *net = genl_info_net(info);
 195	struct nlattr **attrs = info->attrs;
 196
 197	if (!attrs[L2TP_ATTR_CONN_ID]) {
 198		ret = -EINVAL;
 199		goto out;
 200	}
 201	tunnel_id = nla_get_u32(attrs[L2TP_ATTR_CONN_ID]);
 202
 203	if (!attrs[L2TP_ATTR_PEER_CONN_ID]) {
 204		ret = -EINVAL;
 205		goto out;
 206	}
 207	peer_tunnel_id = nla_get_u32(attrs[L2TP_ATTR_PEER_CONN_ID]);
 208
 209	if (!attrs[L2TP_ATTR_PROTO_VERSION]) {
 210		ret = -EINVAL;
 211		goto out;
 212	}
 213	proto_version = nla_get_u8(attrs[L2TP_ATTR_PROTO_VERSION]);
 214
 215	if (!attrs[L2TP_ATTR_ENCAP_TYPE]) {
 216		ret = -EINVAL;
 217		goto out;
 218	}
 219	cfg.encap = nla_get_u16(attrs[L2TP_ATTR_ENCAP_TYPE]);
 220
 221	/* Managed tunnels take the tunnel socket from userspace.
 222	 * Unmanaged tunnels must call out the source and destination addresses
 223	 * for the kernel to create the tunnel socket itself.
 224	 */
 225	if (attrs[L2TP_ATTR_FD]) {
 226		fd = nla_get_u32(attrs[L2TP_ATTR_FD]);
 227	} else {
 228		ret = l2tp_nl_cmd_tunnel_create_get_addr(attrs, &cfg);
 229		if (ret < 0)
 230			goto out;
 231	}
 232
 233	ret = -EINVAL;
 234	switch (cfg.encap) {
 235	case L2TP_ENCAPTYPE_UDP:
 236	case L2TP_ENCAPTYPE_IP:
 237		ret = l2tp_tunnel_create(fd, proto_version, tunnel_id,
 238					 peer_tunnel_id, &cfg, &tunnel);
 239		break;
 240	}
 241
 242	if (ret < 0)
 243		goto out;
 244
 245	refcount_inc(&tunnel->ref_count);
 246	ret = l2tp_tunnel_register(tunnel, net, &cfg);
 247	if (ret < 0) {
 248		kfree(tunnel);
 249		goto out;
 250	}
 251	ret = l2tp_tunnel_notify(&l2tp_nl_family, info, tunnel,
 252				 L2TP_CMD_TUNNEL_CREATE);
 253	l2tp_tunnel_put(tunnel);
 254
 255out:
 256	return ret;
 257}
 258
 259static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
 260{
 261	struct l2tp_tunnel *tunnel;
 262	u32 tunnel_id;
 263	int ret = 0;
 264	struct net *net = genl_info_net(info);
 265
 266	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 267		ret = -EINVAL;
 268		goto out;
 269	}
 270	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 271
 272	tunnel = l2tp_tunnel_get(net, tunnel_id);
 273	if (!tunnel) {
 274		ret = -ENODEV;
 275		goto out;
 276	}
 277
 278	l2tp_tunnel_notify(&l2tp_nl_family, info,
 279			   tunnel, L2TP_CMD_TUNNEL_DELETE);
 280
 281	l2tp_tunnel_delete(tunnel);
 282
 283	l2tp_tunnel_put(tunnel);
 284
 285out:
 286	return ret;
 287}
 288
 289static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info)
 290{
 291	struct l2tp_tunnel *tunnel;
 292	u32 tunnel_id;
 293	int ret = 0;
 294	struct net *net = genl_info_net(info);
 295
 296	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 297		ret = -EINVAL;
 298		goto out;
 299	}
 300	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 301
 302	tunnel = l2tp_tunnel_get(net, tunnel_id);
 303	if (!tunnel) {
 304		ret = -ENODEV;
 305		goto out;
 306	}
 307
 308	ret = l2tp_tunnel_notify(&l2tp_nl_family, info,
 309				 tunnel, L2TP_CMD_TUNNEL_MODIFY);
 310
 311	l2tp_tunnel_put(tunnel);
 312
 313out:
 314	return ret;
 315}
 316
 317#if IS_ENABLED(CONFIG_IPV6)
 318static int l2tp_nl_tunnel_send_addr6(struct sk_buff *skb, struct sock *sk,
 319				     enum l2tp_encap_type encap)
 320{
 321	struct inet_sock *inet = inet_sk(sk);
 322	struct ipv6_pinfo *np = inet6_sk(sk);
 323
 324	switch (encap) {
 325	case L2TP_ENCAPTYPE_UDP:
 326		if (udp_get_no_check6_tx(sk) &&
 327		    nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_TX))
 328			return -1;
 329		if (udp_get_no_check6_rx(sk) &&
 330		    nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_RX))
 331			return -1;
 332		if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 333		    nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
 334			return -1;
 335		fallthrough;
 336	case L2TP_ENCAPTYPE_IP:
 337		if (nla_put_in6_addr(skb, L2TP_ATTR_IP6_SADDR, &np->saddr) ||
 338		    nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR, &sk->sk_v6_daddr))
 339			return -1;
 340		break;
 341	}
 342	return 0;
 343}
 344#endif
 345
 346static int l2tp_nl_tunnel_send_addr4(struct sk_buff *skb, struct sock *sk,
 347				     enum l2tp_encap_type encap)
 348{
 349	struct inet_sock *inet = inet_sk(sk);
 350
 351	switch (encap) {
 352	case L2TP_ENCAPTYPE_UDP:
 353		if (nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx) ||
 354		    nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) ||
 355		    nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport)))
 356			return -1;
 357		fallthrough;
 358	case L2TP_ENCAPTYPE_IP:
 359		if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) ||
 360		    nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr))
 361			return -1;
 362		break;
 363	}
 364
 365	return 0;
 366}
 367
 368/* Append attributes for the tunnel address, handling the different attribute types
 369 * used for different tunnel encapsulation and AF_INET v.s. AF_INET6.
 370 */
 371static int l2tp_nl_tunnel_send_addr(struct sk_buff *skb, struct l2tp_tunnel *tunnel)
 372{
 373	struct sock *sk = tunnel->sock;
 374
 375	if (!sk)
 376		return 0;
 377
 378#if IS_ENABLED(CONFIG_IPV6)
 379	if (sk->sk_family == AF_INET6)
 380		return l2tp_nl_tunnel_send_addr6(skb, sk, tunnel->encap);
 381#endif
 382	return l2tp_nl_tunnel_send_addr4(skb, sk, tunnel->encap);
 383}
 384
 385static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 386			       struct l2tp_tunnel *tunnel, u8 cmd)
 387{
 388	void *hdr;
 389	struct nlattr *nest;
 390
 391	hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 392	if (!hdr)
 393		return -EMSGSIZE;
 394
 395	if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) ||
 396	    nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 397	    nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 398	    nla_put_u32(skb, L2TP_ATTR_DEBUG, 0) ||
 399	    nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap))
 400		goto nla_put_failure;
 401
 402	nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS);
 403	if (!nest)
 404		goto nla_put_failure;
 405
 406	if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
 407			      atomic_long_read(&tunnel->stats.tx_packets),
 408			      L2TP_ATTR_STATS_PAD) ||
 409	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
 410			      atomic_long_read(&tunnel->stats.tx_bytes),
 411			      L2TP_ATTR_STATS_PAD) ||
 412	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
 413			      atomic_long_read(&tunnel->stats.tx_errors),
 414			      L2TP_ATTR_STATS_PAD) ||
 415	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
 416			      atomic_long_read(&tunnel->stats.rx_packets),
 417			      L2TP_ATTR_STATS_PAD) ||
 418	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
 419			      atomic_long_read(&tunnel->stats.rx_bytes),
 420			      L2TP_ATTR_STATS_PAD) ||
 421	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 422			      atomic_long_read(&tunnel->stats.rx_seq_discards),
 423			      L2TP_ATTR_STATS_PAD) ||
 424	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_COOKIE_DISCARDS,
 425			      atomic_long_read(&tunnel->stats.rx_cookie_discards),
 426			      L2TP_ATTR_STATS_PAD) ||
 427	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
 428			      atomic_long_read(&tunnel->stats.rx_oos_packets),
 429			      L2TP_ATTR_STATS_PAD) ||
 430	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
 431			      atomic_long_read(&tunnel->stats.rx_errors),
 432			      L2TP_ATTR_STATS_PAD) ||
 433	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_INVALID,
 434			      atomic_long_read(&tunnel->stats.rx_invalid),
 435			      L2TP_ATTR_STATS_PAD))
 436		goto nla_put_failure;
 437	nla_nest_end(skb, nest);
 438
 439	if (l2tp_nl_tunnel_send_addr(skb, tunnel))
 440		goto nla_put_failure;
 441
 442	genlmsg_end(skb, hdr);
 443	return 0;
 444
 445nla_put_failure:
 446	genlmsg_cancel(skb, hdr);
 447	return -1;
 448}
 449
 450static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info)
 451{
 452	struct l2tp_tunnel *tunnel;
 453	struct sk_buff *msg;
 454	u32 tunnel_id;
 455	int ret = -ENOBUFS;
 456	struct net *net = genl_info_net(info);
 457
 458	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 459		ret = -EINVAL;
 460		goto err;
 461	}
 462
 463	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 464
 465	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 466	if (!msg) {
 467		ret = -ENOMEM;
 468		goto err;
 469	}
 470
 471	tunnel = l2tp_tunnel_get(net, tunnel_id);
 472	if (!tunnel) {
 473		ret = -ENODEV;
 474		goto err_nlmsg;
 475	}
 476
 477	ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq,
 478				  NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET);
 479	if (ret < 0)
 480		goto err_nlmsg_tunnel;
 481
 482	l2tp_tunnel_put(tunnel);
 483
 484	return genlmsg_unicast(net, msg, info->snd_portid);
 485
 486err_nlmsg_tunnel:
 487	l2tp_tunnel_put(tunnel);
 488err_nlmsg:
 489	nlmsg_free(msg);
 490err:
 491	return ret;
 492}
 493
 494struct l2tp_nl_cb_data {
 495	unsigned long tkey;
 496	unsigned long skey;
 497};
 498
 499static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
 500{
 501	struct l2tp_nl_cb_data *cbd = (void *)&cb->ctx[0];
 502	unsigned long key = cbd->tkey;
 503	struct l2tp_tunnel *tunnel;
 504	struct net *net = sock_net(skb->sk);
 505
 506	for (;;) {
 507		tunnel = l2tp_tunnel_get_next(net, &key);
 508		if (!tunnel)
 509			goto out;
 510
 511		if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid,
 512					cb->nlh->nlmsg_seq, NLM_F_MULTI,
 513					tunnel, L2TP_CMD_TUNNEL_GET) < 0) {
 514			l2tp_tunnel_put(tunnel);
 515			goto out;
 516		}
 517		l2tp_tunnel_put(tunnel);
 518
 519		key++;
 520	}
 521
 522out:
 523	cbd->tkey = key;
 524
 525	return skb->len;
 526}
 527
 528static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info)
 529{
 530	u32 tunnel_id = 0;
 531	u32 session_id;
 532	u32 peer_session_id;
 533	int ret = 0;
 534	struct l2tp_tunnel *tunnel;
 535	struct l2tp_session *session;
 536	struct l2tp_session_cfg cfg = { 0, };
 537	struct net *net = genl_info_net(info);
 538
 539	if (!info->attrs[L2TP_ATTR_CONN_ID]) {
 540		ret = -EINVAL;
 541		goto out;
 542	}
 543
 544	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 545	tunnel = l2tp_tunnel_get(net, tunnel_id);
 546	if (!tunnel) {
 547		ret = -ENODEV;
 548		goto out;
 549	}
 550
 551	if (!info->attrs[L2TP_ATTR_SESSION_ID]) {
 552		ret = -EINVAL;
 553		goto out_tunnel;
 554	}
 555	session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
 556
 557	if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) {
 558		ret = -EINVAL;
 559		goto out_tunnel;
 560	}
 561	peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]);
 562
 563	if (!info->attrs[L2TP_ATTR_PW_TYPE]) {
 564		ret = -EINVAL;
 565		goto out_tunnel;
 566	}
 567	cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]);
 568	if (cfg.pw_type >= __L2TP_PWTYPE_MAX) {
 569		ret = -EINVAL;
 570		goto out_tunnel;
 571	}
 572
 573	/* L2TPv2 only accepts PPP pseudo-wires */
 574	if (tunnel->version == 2 && cfg.pw_type != L2TP_PWTYPE_PPP) {
 575		ret = -EPROTONOSUPPORT;
 576		goto out_tunnel;
 577	}
 578
 579	if (tunnel->version > 2) {
 580		if (info->attrs[L2TP_ATTR_L2SPEC_TYPE]) {
 581			cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]);
 582			if (cfg.l2specific_type != L2TP_L2SPECTYPE_DEFAULT &&
 583			    cfg.l2specific_type != L2TP_L2SPECTYPE_NONE) {
 584				ret = -EINVAL;
 585				goto out_tunnel;
 586			}
 587		} else {
 588			cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 589		}
 590
 591		if (info->attrs[L2TP_ATTR_COOKIE]) {
 592			u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 593
 594			if (len > 8) {
 595				ret = -EINVAL;
 596				goto out_tunnel;
 597			}
 598			cfg.cookie_len = len;
 599			memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len);
 600		}
 601		if (info->attrs[L2TP_ATTR_PEER_COOKIE]) {
 602			u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]);
 603
 604			if (len > 8) {
 605				ret = -EINVAL;
 606				goto out_tunnel;
 607			}
 608			cfg.peer_cookie_len = len;
 609			memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len);
 610		}
 611		if (info->attrs[L2TP_ATTR_IFNAME])
 612			cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
 613	}
 614
 615	if (info->attrs[L2TP_ATTR_RECV_SEQ])
 616		cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 617
 618	if (info->attrs[L2TP_ATTR_SEND_SEQ])
 619		cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 620
 621	if (info->attrs[L2TP_ATTR_LNS_MODE])
 622		cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 623
 624	if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 625		cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 626
 627#ifdef CONFIG_MODULES
 628	if (!l2tp_nl_cmd_ops[cfg.pw_type]) {
 629		genl_unlock();
 630		request_module("net-l2tp-type-%u", cfg.pw_type);
 631		genl_lock();
 632	}
 633#endif
 634	if (!l2tp_nl_cmd_ops[cfg.pw_type] || !l2tp_nl_cmd_ops[cfg.pw_type]->session_create) {
 635		ret = -EPROTONOSUPPORT;
 636		goto out_tunnel;
 637	}
 638
 639	ret = l2tp_nl_cmd_ops[cfg.pw_type]->session_create(net, tunnel,
 640							   session_id,
 641							   peer_session_id,
 642							   &cfg);
 643
 644	if (ret >= 0) {
 645		session = l2tp_session_get(net, tunnel->sock, tunnel->version,
 646					   tunnel_id, session_id);
 647		if (session) {
 648			ret = l2tp_session_notify(&l2tp_nl_family, info, session,
 649						  L2TP_CMD_SESSION_CREATE);
 650			l2tp_session_put(session);
 651		}
 652	}
 653
 654out_tunnel:
 655	l2tp_tunnel_put(tunnel);
 656out:
 657	return ret;
 658}
 659
 660static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info)
 661{
 662	int ret = 0;
 663	struct l2tp_session *session;
 664	u16 pw_type;
 665
 666	session = l2tp_nl_session_get(info);
 667	if (!session) {
 668		ret = -ENODEV;
 669		goto out;
 670	}
 671
 672	l2tp_session_notify(&l2tp_nl_family, info,
 673			    session, L2TP_CMD_SESSION_DELETE);
 674
 675	pw_type = session->pwtype;
 676	if (pw_type < __L2TP_PWTYPE_MAX)
 677		if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
 678			l2tp_nl_cmd_ops[pw_type]->session_delete(session);
 679
 680	l2tp_session_put(session);
 681
 682out:
 683	return ret;
 684}
 685
 686static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info)
 687{
 688	int ret = 0;
 689	struct l2tp_session *session;
 690
 691	session = l2tp_nl_session_get(info);
 692	if (!session) {
 693		ret = -ENODEV;
 694		goto out;
 695	}
 696
 697	if (info->attrs[L2TP_ATTR_RECV_SEQ])
 698		session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]);
 699
 700	if (info->attrs[L2TP_ATTR_SEND_SEQ]) {
 701		struct l2tp_tunnel *tunnel = session->tunnel;
 702
 703		session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]);
 704		l2tp_session_set_header_len(session, tunnel->version, tunnel->encap);
 705	}
 706
 707	if (info->attrs[L2TP_ATTR_LNS_MODE])
 708		session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]);
 709
 710	if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
 711		session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);
 712
 713	ret = l2tp_session_notify(&l2tp_nl_family, info,
 714				  session, L2TP_CMD_SESSION_MODIFY);
 715
 716	l2tp_session_put(session);
 717
 718out:
 719	return ret;
 720}
 721
 722static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags,
 723				struct l2tp_session *session, u8 cmd)
 724{
 725	void *hdr;
 726	struct nlattr *nest;
 727	struct l2tp_tunnel *tunnel = session->tunnel;
 728
 729	hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd);
 730	if (!hdr)
 731		return -EMSGSIZE;
 732
 733	if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) ||
 734	    nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) ||
 735	    nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) ||
 736	    nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID, session->peer_session_id) ||
 737	    nla_put_u32(skb, L2TP_ATTR_DEBUG, 0) ||
 738	    nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype))
 739		goto nla_put_failure;
 740
 741	if ((session->ifname[0] &&
 742	     nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) ||
 743	    (session->cookie_len &&
 744	     nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len, session->cookie)) ||
 745	    (session->peer_cookie_len &&
 746	     nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len, session->peer_cookie)) ||
 747	    nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) ||
 748	    nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) ||
 749	    nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) ||
 750	    (l2tp_tunnel_uses_xfrm(tunnel) &&
 751	     nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) ||
 752	    (session->reorder_timeout &&
 753	     nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT,
 754			   session->reorder_timeout, L2TP_ATTR_PAD)))
 755		goto nla_put_failure;
 756
 757	nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS);
 758	if (!nest)
 759		goto nla_put_failure;
 760
 761	if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS,
 762			      atomic_long_read(&session->stats.tx_packets),
 763			      L2TP_ATTR_STATS_PAD) ||
 764	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES,
 765			      atomic_long_read(&session->stats.tx_bytes),
 766			      L2TP_ATTR_STATS_PAD) ||
 767	    nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS,
 768			      atomic_long_read(&session->stats.tx_errors),
 769			      L2TP_ATTR_STATS_PAD) ||
 770	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS,
 771			      atomic_long_read(&session->stats.rx_packets),
 772			      L2TP_ATTR_STATS_PAD) ||
 773	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES,
 774			      atomic_long_read(&session->stats.rx_bytes),
 775			      L2TP_ATTR_STATS_PAD) ||
 776	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS,
 777			      atomic_long_read(&session->stats.rx_seq_discards),
 778			      L2TP_ATTR_STATS_PAD) ||
 779	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_COOKIE_DISCARDS,
 780			      atomic_long_read(&session->stats.rx_cookie_discards),
 781			      L2TP_ATTR_STATS_PAD) ||
 782	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS,
 783			      atomic_long_read(&session->stats.rx_oos_packets),
 784			      L2TP_ATTR_STATS_PAD) ||
 785	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS,
 786			      atomic_long_read(&session->stats.rx_errors),
 787			      L2TP_ATTR_STATS_PAD) ||
 788	    nla_put_u64_64bit(skb, L2TP_ATTR_RX_INVALID,
 789			      atomic_long_read(&session->stats.rx_invalid),
 790			      L2TP_ATTR_STATS_PAD))
 791		goto nla_put_failure;
 792	nla_nest_end(skb, nest);
 793
 794	genlmsg_end(skb, hdr);
 795	return 0;
 796
 797 nla_put_failure:
 798	genlmsg_cancel(skb, hdr);
 799	return -1;
 800}
 801
 802static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
 803{
 804	struct l2tp_session *session;
 805	struct sk_buff *msg;
 806	int ret;
 807
 808	session = l2tp_nl_session_get(info);
 809	if (!session) {
 810		ret = -ENODEV;
 811		goto err;
 812	}
 813
 814	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 815	if (!msg) {
 816		ret = -ENOMEM;
 817		goto err_ref;
 818	}
 819
 820	ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq,
 821				   0, session, L2TP_CMD_SESSION_GET);
 822	if (ret < 0)
 823		goto err_ref_msg;
 824
 825	ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_portid);
 826
 827	l2tp_session_put(session);
 828
 829	return ret;
 830
 831err_ref_msg:
 832	nlmsg_free(msg);
 833err_ref:
 834	l2tp_session_put(session);
 835err:
 836	return ret;
 837}
 838
 839static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)
 840{
 841	struct l2tp_nl_cb_data *cbd = (void *)&cb->ctx[0];
 842	struct net *net = sock_net(skb->sk);
 843	struct l2tp_session *session;
 844	struct l2tp_tunnel *tunnel = NULL;
 845	unsigned long tkey = cbd->tkey;
 846	unsigned long skey = cbd->skey;
 847
 848	for (;;) {
 849		if (!tunnel) {
 850			tunnel = l2tp_tunnel_get_next(net, &tkey);
 851			if (!tunnel)
 852				goto out;
 853		}
 854
 855		session = l2tp_session_get_next(net, tunnel->sock, tunnel->version,
 856						tunnel->tunnel_id, &skey);
 857		if (!session) {
 858			tkey++;
 859			l2tp_tunnel_put(tunnel);
 860			tunnel = NULL;
 861			skey = 0;
 862			continue;
 863		}
 864
 865		if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid,
 866					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
 867					 session, L2TP_CMD_SESSION_GET) < 0) {
 868			l2tp_session_put(session);
 869			l2tp_tunnel_put(tunnel);
 870			break;
 871		}
 872		l2tp_session_put(session);
 873
 874		skey++;
 875	}
 876
 877out:
 878	cbd->tkey = tkey;
 879	cbd->skey = skey;
 880
 881	return skb->len;
 882}
 883
 884static const struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = {
 885	[L2TP_ATTR_NONE]		= { .type = NLA_UNSPEC, },
 886	[L2TP_ATTR_PW_TYPE]		= { .type = NLA_U16, },
 887	[L2TP_ATTR_ENCAP_TYPE]		= { .type = NLA_U16, },
 888	[L2TP_ATTR_OFFSET]		= { .type = NLA_U16, },
 889	[L2TP_ATTR_DATA_SEQ]		= { .type = NLA_U8, },
 890	[L2TP_ATTR_L2SPEC_TYPE]		= { .type = NLA_U8, },
 891	[L2TP_ATTR_L2SPEC_LEN]		= { .type = NLA_U8, },
 892	[L2TP_ATTR_PROTO_VERSION]	= { .type = NLA_U8, },
 893	[L2TP_ATTR_CONN_ID]		= { .type = NLA_U32, },
 894	[L2TP_ATTR_PEER_CONN_ID]	= { .type = NLA_U32, },
 895	[L2TP_ATTR_SESSION_ID]		= { .type = NLA_U32, },
 896	[L2TP_ATTR_PEER_SESSION_ID]	= { .type = NLA_U32, },
 897	[L2TP_ATTR_UDP_CSUM]		= { .type = NLA_U8, },
 898	[L2TP_ATTR_VLAN_ID]		= { .type = NLA_U16, },
 899	[L2TP_ATTR_DEBUG]		= { .type = NLA_U32, },
 900	[L2TP_ATTR_RECV_SEQ]		= { .type = NLA_U8, },
 901	[L2TP_ATTR_SEND_SEQ]		= { .type = NLA_U8, },
 902	[L2TP_ATTR_LNS_MODE]		= { .type = NLA_U8, },
 903	[L2TP_ATTR_USING_IPSEC]		= { .type = NLA_U8, },
 904	[L2TP_ATTR_RECV_TIMEOUT]	= { .type = NLA_MSECS, },
 905	[L2TP_ATTR_FD]			= { .type = NLA_U32, },
 906	[L2TP_ATTR_IP_SADDR]		= { .type = NLA_U32, },
 907	[L2TP_ATTR_IP_DADDR]		= { .type = NLA_U32, },
 908	[L2TP_ATTR_UDP_SPORT]		= { .type = NLA_U16, },
 909	[L2TP_ATTR_UDP_DPORT]		= { .type = NLA_U16, },
 910	[L2TP_ATTR_MTU]			= { .type = NLA_U16, },
 911	[L2TP_ATTR_MRU]			= { .type = NLA_U16, },
 912	[L2TP_ATTR_STATS]		= { .type = NLA_NESTED, },
 913	[L2TP_ATTR_IP6_SADDR] = {
 914		.type = NLA_BINARY,
 915		.len = sizeof(struct in6_addr),
 916	},
 917	[L2TP_ATTR_IP6_DADDR] = {
 918		.type = NLA_BINARY,
 919		.len = sizeof(struct in6_addr),
 920	},
 921	[L2TP_ATTR_IFNAME] = {
 922		.type = NLA_NUL_STRING,
 923		.len = IFNAMSIZ - 1,
 924	},
 925	[L2TP_ATTR_COOKIE] = {
 926		.type = NLA_BINARY,
 927		.len = 8,
 928	},
 929	[L2TP_ATTR_PEER_COOKIE] = {
 930		.type = NLA_BINARY,
 931		.len = 8,
 932	},
 933};
 934
 935static const struct genl_small_ops l2tp_nl_ops[] = {
 936	{
 937		.cmd = L2TP_CMD_NOOP,
 938		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 939		.doit = l2tp_nl_cmd_noop,
 940		/* can be retrieved by unprivileged users */
 941	},
 942	{
 943		.cmd = L2TP_CMD_TUNNEL_CREATE,
 944		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 945		.doit = l2tp_nl_cmd_tunnel_create,
 946		.flags = GENL_UNS_ADMIN_PERM,
 947	},
 948	{
 949		.cmd = L2TP_CMD_TUNNEL_DELETE,
 950		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 951		.doit = l2tp_nl_cmd_tunnel_delete,
 952		.flags = GENL_UNS_ADMIN_PERM,
 953	},
 954	{
 955		.cmd = L2TP_CMD_TUNNEL_MODIFY,
 956		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 957		.doit = l2tp_nl_cmd_tunnel_modify,
 958		.flags = GENL_UNS_ADMIN_PERM,
 959	},
 960	{
 961		.cmd = L2TP_CMD_TUNNEL_GET,
 962		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 963		.doit = l2tp_nl_cmd_tunnel_get,
 964		.dumpit = l2tp_nl_cmd_tunnel_dump,
 965		.flags = GENL_UNS_ADMIN_PERM,
 966	},
 967	{
 968		.cmd = L2TP_CMD_SESSION_CREATE,
 969		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 970		.doit = l2tp_nl_cmd_session_create,
 971		.flags = GENL_UNS_ADMIN_PERM,
 972	},
 973	{
 974		.cmd = L2TP_CMD_SESSION_DELETE,
 975		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 976		.doit = l2tp_nl_cmd_session_delete,
 977		.flags = GENL_UNS_ADMIN_PERM,
 978	},
 979	{
 980		.cmd = L2TP_CMD_SESSION_MODIFY,
 981		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 982		.doit = l2tp_nl_cmd_session_modify,
 983		.flags = GENL_UNS_ADMIN_PERM,
 984	},
 985	{
 986		.cmd = L2TP_CMD_SESSION_GET,
 987		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 988		.doit = l2tp_nl_cmd_session_get,
 989		.dumpit = l2tp_nl_cmd_session_dump,
 990		.flags = GENL_UNS_ADMIN_PERM,
 991	},
 992};
 993
 994static struct genl_family l2tp_nl_family __ro_after_init = {
 995	.name		= L2TP_GENL_NAME,
 996	.version	= L2TP_GENL_VERSION,
 997	.hdrsize	= 0,
 998	.maxattr	= L2TP_ATTR_MAX,
 999	.policy = l2tp_nl_policy,
1000	.netnsok	= true,
1001	.module		= THIS_MODULE,
1002	.small_ops	= l2tp_nl_ops,
1003	.n_small_ops	= ARRAY_SIZE(l2tp_nl_ops),
1004	.resv_start_op	= L2TP_CMD_SESSION_GET + 1,
1005	.mcgrps		= l2tp_multicast_group,
1006	.n_mcgrps	= ARRAY_SIZE(l2tp_multicast_group),
1007};
1008
1009int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops)
1010{
1011	int ret;
1012
1013	ret = -EINVAL;
1014	if (pw_type >= __L2TP_PWTYPE_MAX)
1015		goto err;
1016
1017	genl_lock();
1018	ret = -EBUSY;
1019	if (l2tp_nl_cmd_ops[pw_type])
1020		goto out;
1021
1022	l2tp_nl_cmd_ops[pw_type] = ops;
1023	ret = 0;
1024
1025out:
1026	genl_unlock();
1027err:
1028	return ret;
1029}
1030EXPORT_SYMBOL_GPL(l2tp_nl_register_ops);
1031
1032void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type)
1033{
1034	if (pw_type < __L2TP_PWTYPE_MAX) {
1035		genl_lock();
1036		l2tp_nl_cmd_ops[pw_type] = NULL;
1037		genl_unlock();
1038	}
1039}
1040EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops);
1041
1042static int __init l2tp_nl_init(void)
1043{
1044	pr_info("L2TP netlink interface\n");
1045	return genl_register_family(&l2tp_nl_family);
1046}
1047
1048static void l2tp_nl_cleanup(void)
1049{
1050	genl_unregister_family(&l2tp_nl_family);
1051}
1052
1053module_init(l2tp_nl_init);
1054module_exit(l2tp_nl_cleanup);
1055
1056MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
1057MODULE_DESCRIPTION("L2TP netlink");
1058MODULE_LICENSE("GPL");
1059MODULE_VERSION("1.0");
1060MODULE_ALIAS_GENL_FAMILY("l2tp");