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v4.17
   1/*
   2 * Copyright (c) 2013 Nicira, Inc.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of version 2 of the GNU General Public
   6 * License as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public License
  14 * along with this program; if not, write to the Free Software
  15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16 * 02110-1301, USA
  17 */
  18
  19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  20
  21#include <linux/capability.h>
  22#include <linux/module.h>
  23#include <linux/types.h>
  24#include <linux/kernel.h>
  25#include <linux/slab.h>
  26#include <linux/uaccess.h>
  27#include <linux/skbuff.h>
  28#include <linux/netdevice.h>
  29#include <linux/in.h>
  30#include <linux/tcp.h>
  31#include <linux/udp.h>
  32#include <linux/if_arp.h>
 
  33#include <linux/init.h>
  34#include <linux/in6.h>
  35#include <linux/inetdevice.h>
  36#include <linux/igmp.h>
  37#include <linux/netfilter_ipv4.h>
  38#include <linux/etherdevice.h>
  39#include <linux/if_ether.h>
  40#include <linux/if_vlan.h>
  41#include <linux/rculist.h>
  42#include <linux/err.h>
  43
  44#include <net/sock.h>
  45#include <net/ip.h>
  46#include <net/icmp.h>
  47#include <net/protocol.h>
  48#include <net/ip_tunnels.h>
  49#include <net/arp.h>
  50#include <net/checksum.h>
  51#include <net/dsfield.h>
  52#include <net/inet_ecn.h>
  53#include <net/xfrm.h>
  54#include <net/net_namespace.h>
  55#include <net/netns/generic.h>
  56#include <net/rtnetlink.h>
  57#include <net/udp.h>
  58#include <net/dst_metadata.h>
  59
  60#if IS_ENABLED(CONFIG_IPV6)
  61#include <net/ipv6.h>
  62#include <net/ip6_fib.h>
  63#include <net/ip6_route.h>
  64#endif
  65
  66static unsigned int ip_tunnel_hash(__be32 key, __be32 remote)
  67{
  68	return hash_32((__force u32)key ^ (__force u32)remote,
  69			 IP_TNL_HASH_BITS);
  70}
  71
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  72static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p,
  73				__be16 flags, __be32 key)
  74{
  75	if (p->i_flags & TUNNEL_KEY) {
  76		if (flags & TUNNEL_KEY)
  77			return key == p->i_key;
  78		else
  79			/* key expected, none present */
  80			return false;
  81	} else
  82		return !(flags & TUNNEL_KEY);
  83}
  84
  85/* Fallback tunnel: no source, no destination, no key, no options
  86
  87   Tunnel hash table:
  88   We require exact key match i.e. if a key is present in packet
  89   it will match only tunnel with the same key; if it is not present,
  90   it will match only keyless tunnel.
  91
  92   All keysless packets, if not matched configured keyless tunnels
  93   will match fallback tunnel.
  94   Given src, dst and key, find appropriate for input tunnel.
  95*/
  96struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
  97				   int link, __be16 flags,
  98				   __be32 remote, __be32 local,
  99				   __be32 key)
 100{
 101	unsigned int hash;
 102	struct ip_tunnel *t, *cand = NULL;
 103	struct hlist_head *head;
 104
 105	hash = ip_tunnel_hash(key, remote);
 106	head = &itn->tunnels[hash];
 107
 108	hlist_for_each_entry_rcu(t, head, hash_node) {
 109		if (local != t->parms.iph.saddr ||
 110		    remote != t->parms.iph.daddr ||
 111		    !(t->dev->flags & IFF_UP))
 112			continue;
 113
 114		if (!ip_tunnel_key_match(&t->parms, flags, key))
 115			continue;
 116
 117		if (t->parms.link == link)
 118			return t;
 119		else
 120			cand = t;
 121	}
 122
 123	hlist_for_each_entry_rcu(t, head, hash_node) {
 124		if (remote != t->parms.iph.daddr ||
 125		    t->parms.iph.saddr != 0 ||
 126		    !(t->dev->flags & IFF_UP))
 127			continue;
 128
 129		if (!ip_tunnel_key_match(&t->parms, flags, key))
 130			continue;
 131
 132		if (t->parms.link == link)
 133			return t;
 134		else if (!cand)
 135			cand = t;
 136	}
 137
 138	hash = ip_tunnel_hash(key, 0);
 139	head = &itn->tunnels[hash];
 140
 141	hlist_for_each_entry_rcu(t, head, hash_node) {
 142		if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) &&
 143		    (local != t->parms.iph.daddr || !ipv4_is_multicast(local)))
 144			continue;
 145
 146		if (!(t->dev->flags & IFF_UP))
 147			continue;
 148
 149		if (!ip_tunnel_key_match(&t->parms, flags, key))
 150			continue;
 151
 152		if (t->parms.link == link)
 153			return t;
 154		else if (!cand)
 155			cand = t;
 156	}
 157
 158	if (flags & TUNNEL_NO_KEY)
 159		goto skip_key_lookup;
 160
 161	hlist_for_each_entry_rcu(t, head, hash_node) {
 162		if (t->parms.i_key != key ||
 163		    t->parms.iph.saddr != 0 ||
 164		    t->parms.iph.daddr != 0 ||
 165		    !(t->dev->flags & IFF_UP))
 166			continue;
 167
 168		if (t->parms.link == link)
 169			return t;
 170		else if (!cand)
 171			cand = t;
 172	}
 173
 174skip_key_lookup:
 175	if (cand)
 176		return cand;
 177
 178	t = rcu_dereference(itn->collect_md_tun);
 179	if (t && t->dev->flags & IFF_UP)
 180		return t;
 181
 182	if (itn->fb_tunnel_dev && itn->fb_tunnel_dev->flags & IFF_UP)
 183		return netdev_priv(itn->fb_tunnel_dev);
 184
 
 185	return NULL;
 186}
 187EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
 188
 189static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn,
 190				    struct ip_tunnel_parm *parms)
 191{
 192	unsigned int h;
 193	__be32 remote;
 194	__be32 i_key = parms->i_key;
 195
 196	if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr))
 197		remote = parms->iph.daddr;
 198	else
 199		remote = 0;
 200
 201	if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI))
 202		i_key = 0;
 203
 204	h = ip_tunnel_hash(i_key, remote);
 205	return &itn->tunnels[h];
 206}
 207
 208static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t)
 209{
 210	struct hlist_head *head = ip_bucket(itn, &t->parms);
 211
 212	if (t->collect_md)
 213		rcu_assign_pointer(itn->collect_md_tun, t);
 214	hlist_add_head_rcu(&t->hash_node, head);
 215}
 216
 217static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t)
 218{
 219	if (t->collect_md)
 220		rcu_assign_pointer(itn->collect_md_tun, NULL);
 221	hlist_del_init_rcu(&t->hash_node);
 222}
 223
 224static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
 225					struct ip_tunnel_parm *parms,
 226					int type)
 227{
 228	__be32 remote = parms->iph.daddr;
 229	__be32 local = parms->iph.saddr;
 230	__be32 key = parms->i_key;
 231	__be16 flags = parms->i_flags;
 232	int link = parms->link;
 233	struct ip_tunnel *t = NULL;
 234	struct hlist_head *head = ip_bucket(itn, parms);
 235
 236	hlist_for_each_entry_rcu(t, head, hash_node) {
 237		if (local == t->parms.iph.saddr &&
 238		    remote == t->parms.iph.daddr &&
 
 239		    link == t->parms.link &&
 240		    type == t->dev->type &&
 241		    ip_tunnel_key_match(&t->parms, flags, key))
 242			break;
 243	}
 244	return t;
 245}
 246
 247static struct net_device *__ip_tunnel_create(struct net *net,
 248					     const struct rtnl_link_ops *ops,
 249					     struct ip_tunnel_parm *parms)
 250{
 251	int err;
 252	struct ip_tunnel *tunnel;
 253	struct net_device *dev;
 254	char name[IFNAMSIZ];
 255
 256	err = -E2BIG;
 257	if (parms->name[0]) {
 258		if (!dev_valid_name(parms->name))
 259			goto failed;
 260		strlcpy(name, parms->name, IFNAMSIZ);
 261	} else {
 262		if (strlen(ops->kind) > (IFNAMSIZ - 3))
 
 263			goto failed;
 
 264		strlcpy(name, ops->kind, IFNAMSIZ);
 265		strncat(name, "%d", 2);
 266	}
 267
 268	ASSERT_RTNL();
 269	dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup);
 270	if (!dev) {
 271		err = -ENOMEM;
 272		goto failed;
 273	}
 274	dev_net_set(dev, net);
 275
 276	dev->rtnl_link_ops = ops;
 277
 278	tunnel = netdev_priv(dev);
 279	tunnel->parms = *parms;
 280	tunnel->net = net;
 281
 282	err = register_netdevice(dev);
 283	if (err)
 284		goto failed_free;
 285
 286	return dev;
 287
 288failed_free:
 289	free_netdev(dev);
 290failed:
 291	return ERR_PTR(err);
 292}
 293
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 294static int ip_tunnel_bind_dev(struct net_device *dev)
 295{
 296	struct net_device *tdev = NULL;
 297	struct ip_tunnel *tunnel = netdev_priv(dev);
 298	const struct iphdr *iph;
 299	int hlen = LL_MAX_HEADER;
 300	int mtu = ETH_DATA_LEN;
 301	int t_hlen = tunnel->hlen + sizeof(struct iphdr);
 302
 303	iph = &tunnel->parms.iph;
 304
 305	/* Guess output device to choose reasonable mtu and needed_headroom */
 306	if (iph->daddr) {
 307		struct flowi4 fl4;
 308		struct rtable *rt;
 309
 310		ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr,
 311				    iph->saddr, tunnel->parms.o_key,
 312				    RT_TOS(iph->tos), tunnel->parms.link,
 313				    tunnel->fwmark);
 314		rt = ip_route_output_key(tunnel->net, &fl4);
 315
 316		if (!IS_ERR(rt)) {
 317			tdev = rt->dst.dev;
 
 318			ip_rt_put(rt);
 319		}
 320		if (dev->type != ARPHRD_ETHER)
 321			dev->flags |= IFF_POINTOPOINT;
 322
 323		dst_cache_reset(&tunnel->dst_cache);
 324	}
 325
 326	if (!tdev && tunnel->parms.link)
 327		tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
 328
 329	if (tdev) {
 330		hlen = tdev->hard_header_len + tdev->needed_headroom;
 331		mtu = min(tdev->mtu, IP_MAX_MTU);
 332	}
 
 333
 334	dev->needed_headroom = t_hlen + hlen;
 335	mtu -= (dev->hard_header_len + t_hlen);
 336
 337	if (mtu < IPV4_MIN_MTU)
 338		mtu = IPV4_MIN_MTU;
 339
 340	return mtu;
 341}
 342
 343static struct ip_tunnel *ip_tunnel_create(struct net *net,
 344					  struct ip_tunnel_net *itn,
 345					  struct ip_tunnel_parm *parms)
 346{
 347	struct ip_tunnel *nt;
 348	struct net_device *dev;
 349	int t_hlen;
 350	int mtu;
 351	int err;
 352
 353	dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms);
 
 
 354	if (IS_ERR(dev))
 355		return ERR_CAST(dev);
 356
 357	mtu = ip_tunnel_bind_dev(dev);
 358	err = dev_set_mtu(dev, mtu);
 359	if (err)
 360		goto err_dev_set_mtu;
 361
 362	nt = netdev_priv(dev);
 363	t_hlen = nt->hlen + sizeof(struct iphdr);
 364	dev->min_mtu = ETH_MIN_MTU;
 365	dev->max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen;
 366	ip_tunnel_add(itn, nt);
 367	return nt;
 368
 369err_dev_set_mtu:
 370	unregister_netdevice(dev);
 371	return ERR_PTR(err);
 372}
 373
 374int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 375		  const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
 376		  bool log_ecn_error)
 377{
 378	struct pcpu_sw_netstats *tstats;
 379	const struct iphdr *iph = ip_hdr(skb);
 380	int err;
 381
 382#ifdef CONFIG_NET_IPGRE_BROADCAST
 383	if (ipv4_is_multicast(iph->daddr)) {
 384		tunnel->dev->stats.multicast++;
 385		skb->pkt_type = PACKET_BROADCAST;
 386	}
 387#endif
 388
 389	if ((!(tpi->flags&TUNNEL_CSUM) &&  (tunnel->parms.i_flags&TUNNEL_CSUM)) ||
 390	     ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) {
 391		tunnel->dev->stats.rx_crc_errors++;
 392		tunnel->dev->stats.rx_errors++;
 393		goto drop;
 394	}
 395
 396	if (tunnel->parms.i_flags&TUNNEL_SEQ) {
 397		if (!(tpi->flags&TUNNEL_SEQ) ||
 398		    (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 399			tunnel->dev->stats.rx_fifo_errors++;
 400			tunnel->dev->stats.rx_errors++;
 401			goto drop;
 402		}
 403		tunnel->i_seqno = ntohl(tpi->seq) + 1;
 404	}
 405
 406	skb_reset_network_header(skb);
 407
 408	err = IP_ECN_decapsulate(iph, skb);
 409	if (unlikely(err)) {
 410		if (log_ecn_error)
 411			net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
 412					&iph->saddr, iph->tos);
 413		if (err > 1) {
 414			++tunnel->dev->stats.rx_frame_errors;
 415			++tunnel->dev->stats.rx_errors;
 416			goto drop;
 417		}
 418	}
 419
 420	tstats = this_cpu_ptr(tunnel->dev->tstats);
 421	u64_stats_update_begin(&tstats->syncp);
 422	tstats->rx_packets++;
 423	tstats->rx_bytes += skb->len;
 424	u64_stats_update_end(&tstats->syncp);
 425
 426	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 427
 428	if (tunnel->dev->type == ARPHRD_ETHER) {
 429		skb->protocol = eth_type_trans(skb, tunnel->dev);
 430		skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 431	} else {
 432		skb->dev = tunnel->dev;
 433	}
 434
 435	if (tun_dst)
 436		skb_dst_set(skb, (struct dst_entry *)tun_dst);
 437
 438	gro_cells_receive(&tunnel->gro_cells, skb);
 439	return 0;
 440
 441drop:
 442	if (tun_dst)
 443		dst_release((struct dst_entry *)tun_dst);
 444	kfree_skb(skb);
 445	return 0;
 446}
 447EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
 448
 449int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops,
 450			    unsigned int num)
 451{
 452	if (num >= MAX_IPTUN_ENCAP_OPS)
 453		return -ERANGE;
 454
 455	return !cmpxchg((const struct ip_tunnel_encap_ops **)
 456			&iptun_encaps[num],
 457			NULL, ops) ? 0 : -1;
 458}
 459EXPORT_SYMBOL(ip_tunnel_encap_add_ops);
 460
 461int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops,
 462			    unsigned int num)
 463{
 464	int ret;
 465
 466	if (num >= MAX_IPTUN_ENCAP_OPS)
 467		return -ERANGE;
 468
 469	ret = (cmpxchg((const struct ip_tunnel_encap_ops **)
 470		       &iptun_encaps[num],
 471		       ops, NULL) == ops) ? 0 : -1;
 472
 473	synchronize_net();
 474
 475	return ret;
 476}
 477EXPORT_SYMBOL(ip_tunnel_encap_del_ops);
 478
 479int ip_tunnel_encap_setup(struct ip_tunnel *t,
 480			  struct ip_tunnel_encap *ipencap)
 481{
 482	int hlen;
 483
 484	memset(&t->encap, 0, sizeof(t->encap));
 485
 486	hlen = ip_encap_hlen(ipencap);
 487	if (hlen < 0)
 488		return hlen;
 489
 490	t->encap.type = ipencap->type;
 491	t->encap.sport = ipencap->sport;
 492	t->encap.dport = ipencap->dport;
 493	t->encap.flags = ipencap->flags;
 494
 495	t->encap_hlen = hlen;
 496	t->hlen = t->encap_hlen + t->tun_hlen;
 497
 498	return 0;
 499}
 500EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
 501
 502static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
 503			    struct rtable *rt, __be16 df,
 504			    const struct iphdr *inner_iph)
 505{
 506	struct ip_tunnel *tunnel = netdev_priv(dev);
 507	int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len;
 508	int mtu;
 509
 510	if (df)
 511		mtu = dst_mtu(&rt->dst) - dev->hard_header_len
 512					- sizeof(struct iphdr) - tunnel->hlen;
 513	else
 514		mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
 515
 516	skb_dst_update_pmtu(skb, mtu);
 
 517
 518	if (skb->protocol == htons(ETH_P_IP)) {
 519		if (!skb_is_gso(skb) &&
 520		    (inner_iph->frag_off & htons(IP_DF)) &&
 521		    mtu < pkt_size) {
 522			memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 523			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
 524			return -E2BIG;
 525		}
 526	}
 527#if IS_ENABLED(CONFIG_IPV6)
 528	else if (skb->protocol == htons(ETH_P_IPV6)) {
 529		struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
 530
 531		if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
 532			   mtu >= IPV6_MIN_MTU) {
 533			if ((tunnel->parms.iph.daddr &&
 534			    !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
 535			    rt6->rt6i_dst.plen == 128) {
 536				rt6->rt6i_flags |= RTF_MODIFIED;
 537				dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
 538			}
 539		}
 540
 541		if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
 542					mtu < pkt_size) {
 543			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 544			return -E2BIG;
 545		}
 546	}
 547#endif
 548	return 0;
 549}
 550
 551void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
 552{
 553	struct ip_tunnel *tunnel = netdev_priv(dev);
 554	u32 headroom = sizeof(struct iphdr);
 555	struct ip_tunnel_info *tun_info;
 556	const struct ip_tunnel_key *key;
 557	const struct iphdr *inner_iph;
 558	struct rtable *rt;
 559	struct flowi4 fl4;
 560	__be16 df = 0;
 561	u8 tos, ttl;
 562
 563	tun_info = skb_tunnel_info(skb);
 564	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
 565		     ip_tunnel_info_af(tun_info) != AF_INET))
 566		goto tx_error;
 567	key = &tun_info->key;
 568	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 569	inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
 570	tos = key->tos;
 571	if (tos == 1) {
 572		if (skb->protocol == htons(ETH_P_IP))
 573			tos = inner_iph->tos;
 574		else if (skb->protocol == htons(ETH_P_IPV6))
 575			tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
 576	}
 577	ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0,
 578			    RT_TOS(tos), tunnel->parms.link, tunnel->fwmark);
 579	if (tunnel->encap.type != TUNNEL_ENCAP_NONE)
 580		goto tx_error;
 581	rt = ip_route_output_key(tunnel->net, &fl4);
 582	if (IS_ERR(rt)) {
 583		dev->stats.tx_carrier_errors++;
 584		goto tx_error;
 585	}
 586	if (rt->dst.dev == dev) {
 587		ip_rt_put(rt);
 588		dev->stats.collisions++;
 589		goto tx_error;
 590	}
 591	tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
 592	ttl = key->ttl;
 593	if (ttl == 0) {
 594		if (skb->protocol == htons(ETH_P_IP))
 595			ttl = inner_iph->ttl;
 596		else if (skb->protocol == htons(ETH_P_IPV6))
 597			ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
 598		else
 599			ttl = ip4_dst_hoplimit(&rt->dst);
 600	}
 601	if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
 602		df = htons(IP_DF);
 603	else if (skb->protocol == htons(ETH_P_IP))
 604		df = inner_iph->frag_off & htons(IP_DF);
 605	headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
 606	if (headroom > dev->needed_headroom)
 607		dev->needed_headroom = headroom;
 608
 609	if (skb_cow_head(skb, dev->needed_headroom)) {
 610		ip_rt_put(rt);
 611		goto tx_dropped;
 612	}
 613	iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
 614		      df, !net_eq(tunnel->net, dev_net(dev)));
 615	return;
 616tx_error:
 617	dev->stats.tx_errors++;
 618	goto kfree;
 619tx_dropped:
 620	dev->stats.tx_dropped++;
 621kfree:
 622	kfree_skb(skb);
 623}
 624EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
 625
 626void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 627		    const struct iphdr *tnl_params, u8 protocol)
 628{
 629	struct ip_tunnel *tunnel = netdev_priv(dev);
 630	const struct iphdr *inner_iph;
 631	struct flowi4 fl4;
 632	u8     tos, ttl;
 633	__be16 df;
 634	struct rtable *rt;		/* Route to the other host */
 635	unsigned int max_headroom;	/* The extra header space needed */
 636	__be32 dst;
 
 637	bool connected;
 638
 639	inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
 640	connected = (tunnel->parms.iph.daddr != 0);
 641
 642	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 643
 644	dst = tnl_params->daddr;
 645	if (dst == 0) {
 646		/* NBMA tunnel */
 647
 648		if (!skb_dst(skb)) {
 649			dev->stats.tx_fifo_errors++;
 650			goto tx_error;
 651		}
 652
 653		if (skb->protocol == htons(ETH_P_IP)) {
 654			rt = skb_rtable(skb);
 655			dst = rt_nexthop(rt, inner_iph->daddr);
 656		}
 657#if IS_ENABLED(CONFIG_IPV6)
 658		else if (skb->protocol == htons(ETH_P_IPV6)) {
 659			const struct in6_addr *addr6;
 660			struct neighbour *neigh;
 661			bool do_tx_error_icmp;
 662			int addr_type;
 663
 664			neigh = dst_neigh_lookup(skb_dst(skb),
 665						 &ipv6_hdr(skb)->daddr);
 666			if (!neigh)
 667				goto tx_error;
 668
 669			addr6 = (const struct in6_addr *)&neigh->primary_key;
 670			addr_type = ipv6_addr_type(addr6);
 671
 672			if (addr_type == IPV6_ADDR_ANY) {
 673				addr6 = &ipv6_hdr(skb)->daddr;
 674				addr_type = ipv6_addr_type(addr6);
 675			}
 676
 677			if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
 678				do_tx_error_icmp = true;
 679			else {
 680				do_tx_error_icmp = false;
 681				dst = addr6->s6_addr32[3];
 682			}
 683			neigh_release(neigh);
 684			if (do_tx_error_icmp)
 685				goto tx_error_icmp;
 686		}
 687#endif
 688		else
 689			goto tx_error;
 690
 691		connected = false;
 692	}
 693
 694	tos = tnl_params->tos;
 695	if (tos & 0x1) {
 696		tos &= ~0x1;
 697		if (skb->protocol == htons(ETH_P_IP)) {
 698			tos = inner_iph->tos;
 699			connected = false;
 700		} else if (skb->protocol == htons(ETH_P_IPV6)) {
 701			tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
 702			connected = false;
 703		}
 704	}
 705
 706	ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr,
 707			    tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link,
 708			    tunnel->fwmark);
 709
 710	if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0)
 711		goto tx_error;
 712
 713	rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) :
 714			 NULL;
 715
 716	if (!rt) {
 717		rt = ip_route_output_key(tunnel->net, &fl4);
 718
 719		if (IS_ERR(rt)) {
 720			dev->stats.tx_carrier_errors++;
 721			goto tx_error;
 722		}
 723		if (connected)
 724			dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
 725					  fl4.saddr);
 726	}
 727
 728	if (rt->dst.dev == dev) {
 729		ip_rt_put(rt);
 730		dev->stats.collisions++;
 731		goto tx_error;
 732	}
 733
 734	if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) {
 735		ip_rt_put(rt);
 736		goto tx_error;
 737	}
 738
 739	if (tunnel->err_count > 0) {
 740		if (time_before(jiffies,
 741				tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
 742			tunnel->err_count--;
 743
 
 744			dst_link_failure(skb);
 745		} else
 746			tunnel->err_count = 0;
 747	}
 748
 749	tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
 750	ttl = tnl_params->ttl;
 751	if (ttl == 0) {
 752		if (skb->protocol == htons(ETH_P_IP))
 753			ttl = inner_iph->ttl;
 754#if IS_ENABLED(CONFIG_IPV6)
 755		else if (skb->protocol == htons(ETH_P_IPV6))
 756			ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
 757#endif
 758		else
 759			ttl = ip4_dst_hoplimit(&rt->dst);
 760	}
 761
 762	df = tnl_params->frag_off;
 763	if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
 764		df |= (inner_iph->frag_off&htons(IP_DF));
 765
 766	max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
 767			+ rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
 768	if (max_headroom > dev->needed_headroom)
 769		dev->needed_headroom = max_headroom;
 770
 771	if (skb_cow_head(skb, dev->needed_headroom)) {
 772		ip_rt_put(rt);
 773		dev->stats.tx_dropped++;
 774		kfree_skb(skb);
 775		return;
 776	}
 777
 778	iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
 779		      df, !net_eq(tunnel->net, dev_net(dev)));
 
 
 780	return;
 781
 782#if IS_ENABLED(CONFIG_IPV6)
 783tx_error_icmp:
 784	dst_link_failure(skb);
 785#endif
 786tx_error:
 787	dev->stats.tx_errors++;
 788	kfree_skb(skb);
 789}
 790EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
 791
 792static void ip_tunnel_update(struct ip_tunnel_net *itn,
 793			     struct ip_tunnel *t,
 794			     struct net_device *dev,
 795			     struct ip_tunnel_parm *p,
 796			     bool set_mtu,
 797			     __u32 fwmark)
 798{
 799	ip_tunnel_del(itn, t);
 800	t->parms.iph.saddr = p->iph.saddr;
 801	t->parms.iph.daddr = p->iph.daddr;
 802	t->parms.i_key = p->i_key;
 803	t->parms.o_key = p->o_key;
 804	if (dev->type != ARPHRD_ETHER) {
 805		memcpy(dev->dev_addr, &p->iph.saddr, 4);
 806		memcpy(dev->broadcast, &p->iph.daddr, 4);
 807	}
 808	ip_tunnel_add(itn, t);
 809
 810	t->parms.iph.ttl = p->iph.ttl;
 811	t->parms.iph.tos = p->iph.tos;
 812	t->parms.iph.frag_off = p->iph.frag_off;
 813
 814	if (t->parms.link != p->link || t->fwmark != fwmark) {
 815		int mtu;
 816
 817		t->parms.link = p->link;
 818		t->fwmark = fwmark;
 819		mtu = ip_tunnel_bind_dev(dev);
 820		if (set_mtu)
 821			dev->mtu = mtu;
 822	}
 823	dst_cache_reset(&t->dst_cache);
 824	netdev_state_change(dev);
 825}
 826
 827int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
 828{
 829	int err = 0;
 830	struct ip_tunnel *t = netdev_priv(dev);
 831	struct net *net = t->net;
 832	struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
 833
 
 834	switch (cmd) {
 835	case SIOCGETTUNNEL:
 836		if (dev == itn->fb_tunnel_dev) {
 837			t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
 838			if (!t)
 839				t = netdev_priv(dev);
 840		}
 841		memcpy(p, &t->parms, sizeof(*p));
 842		break;
 843
 844	case SIOCADDTUNNEL:
 845	case SIOCCHGTUNNEL:
 846		err = -EPERM;
 847		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 848			goto done;
 849		if (p->iph.ttl)
 850			p->iph.frag_off |= htons(IP_DF);
 851		if (!(p->i_flags & VTI_ISVTI)) {
 852			if (!(p->i_flags & TUNNEL_KEY))
 853				p->i_key = 0;
 854			if (!(p->o_flags & TUNNEL_KEY))
 855				p->o_key = 0;
 856		}
 857
 858		t = ip_tunnel_find(itn, p, itn->type);
 859
 860		if (cmd == SIOCADDTUNNEL) {
 861			if (!t) {
 862				t = ip_tunnel_create(net, itn, p);
 863				err = PTR_ERR_OR_ZERO(t);
 864				break;
 865			}
 866
 867			err = -EEXIST;
 868			break;
 869		}
 870		if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
 871			if (t) {
 872				if (t->dev != dev) {
 873					err = -EEXIST;
 874					break;
 875				}
 876			} else {
 877				unsigned int nflags = 0;
 878
 879				if (ipv4_is_multicast(p->iph.daddr))
 880					nflags = IFF_BROADCAST;
 881				else if (p->iph.daddr)
 882					nflags = IFF_POINTOPOINT;
 883
 884				if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
 885					err = -EINVAL;
 886					break;
 887				}
 888
 889				t = netdev_priv(dev);
 890			}
 891		}
 892
 893		if (t) {
 894			err = 0;
 895			ip_tunnel_update(itn, t, dev, p, true, 0);
 896		} else {
 897			err = -ENOENT;
 898		}
 899		break;
 900
 901	case SIOCDELTUNNEL:
 902		err = -EPERM;
 903		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 904			goto done;
 905
 906		if (dev == itn->fb_tunnel_dev) {
 907			err = -ENOENT;
 908			t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
 909			if (!t)
 910				goto done;
 911			err = -EPERM;
 912			if (t == netdev_priv(itn->fb_tunnel_dev))
 913				goto done;
 914			dev = t->dev;
 915		}
 916		unregister_netdevice(dev);
 917		err = 0;
 918		break;
 919
 920	default:
 921		err = -EINVAL;
 922	}
 923
 924done:
 925	return err;
 926}
 927EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
 928
 929int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
 930{
 931	struct ip_tunnel *tunnel = netdev_priv(dev);
 932	int t_hlen = tunnel->hlen + sizeof(struct iphdr);
 933	int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen;
 934
 935	if (new_mtu < ETH_MIN_MTU)
 
 936		return -EINVAL;
 937
 938	if (new_mtu > max_mtu) {
 939		if (strict)
 940			return -EINVAL;
 941
 942		new_mtu = max_mtu;
 943	}
 944
 945	dev->mtu = new_mtu;
 946	return 0;
 947}
 948EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
 949
 950int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
 951{
 952	return __ip_tunnel_change_mtu(dev, new_mtu, true);
 953}
 954EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
 955
 956static void ip_tunnel_dev_free(struct net_device *dev)
 957{
 958	struct ip_tunnel *tunnel = netdev_priv(dev);
 959
 960	gro_cells_destroy(&tunnel->gro_cells);
 961	dst_cache_destroy(&tunnel->dst_cache);
 962	free_percpu(dev->tstats);
 
 963}
 964
 965void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
 966{
 967	struct ip_tunnel *tunnel = netdev_priv(dev);
 968	struct ip_tunnel_net *itn;
 969
 970	itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
 971
 972	if (itn->fb_tunnel_dev != dev) {
 973		ip_tunnel_del(itn, netdev_priv(dev));
 974		unregister_netdevice_queue(dev, head);
 975	}
 976}
 977EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
 978
 979struct net *ip_tunnel_get_link_net(const struct net_device *dev)
 980{
 981	struct ip_tunnel *tunnel = netdev_priv(dev);
 982
 983	return tunnel->net;
 984}
 985EXPORT_SYMBOL(ip_tunnel_get_link_net);
 986
 987int ip_tunnel_get_iflink(const struct net_device *dev)
 988{
 989	struct ip_tunnel *tunnel = netdev_priv(dev);
 990
 991	return tunnel->parms.link;
 992}
 993EXPORT_SYMBOL(ip_tunnel_get_iflink);
 994
 995int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
 996				  struct rtnl_link_ops *ops, char *devname)
 997{
 998	struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
 999	struct ip_tunnel_parm parms;
1000	unsigned int i;
1001
1002	itn->rtnl_link_ops = ops;
1003	for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1004		INIT_HLIST_HEAD(&itn->tunnels[i]);
1005
1006	if (!ops || !net_has_fallback_tunnels(net)) {
1007		struct ip_tunnel_net *it_init_net;
1008
1009		it_init_net = net_generic(&init_net, ip_tnl_net_id);
1010		itn->type = it_init_net->type;
1011		itn->fb_tunnel_dev = NULL;
1012		return 0;
1013	}
1014
1015	memset(&parms, 0, sizeof(parms));
1016	if (devname)
1017		strlcpy(parms.name, devname, IFNAMSIZ);
1018
1019	rtnl_lock();
1020	itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1021	/* FB netdevice is special: we have one, and only one per netns.
1022	 * Allowing to move it to another netns is clearly unsafe.
1023	 */
1024	if (!IS_ERR(itn->fb_tunnel_dev)) {
1025		itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1026		itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1027		ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1028		itn->type = itn->fb_tunnel_dev->type;
1029	}
1030	rtnl_unlock();
1031
1032	return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1033}
1034EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1035
1036static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn,
1037			      struct list_head *head,
1038			      struct rtnl_link_ops *ops)
1039{
 
1040	struct net_device *dev, *aux;
1041	int h;
1042
1043	for_each_netdev_safe(net, dev, aux)
1044		if (dev->rtnl_link_ops == ops)
1045			unregister_netdevice_queue(dev, head);
1046
1047	for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1048		struct ip_tunnel *t;
1049		struct hlist_node *n;
1050		struct hlist_head *thead = &itn->tunnels[h];
1051
1052		hlist_for_each_entry_safe(t, n, thead, hash_node)
1053			/* If dev is in the same netns, it has already
1054			 * been added to the list by the previous loop.
1055			 */
1056			if (!net_eq(dev_net(t->dev), net))
1057				unregister_netdevice_queue(t->dev, head);
1058	}
1059}
1060
1061void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id,
1062			   struct rtnl_link_ops *ops)
1063{
1064	struct ip_tunnel_net *itn;
1065	struct net *net;
1066	LIST_HEAD(list);
1067
1068	rtnl_lock();
1069	list_for_each_entry(net, net_list, exit_list) {
1070		itn = net_generic(net, id);
1071		ip_tunnel_destroy(net, itn, &list, ops);
1072	}
1073	unregister_netdevice_many(&list);
1074	rtnl_unlock();
1075}
1076EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets);
1077
1078int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1079		      struct ip_tunnel_parm *p, __u32 fwmark)
1080{
1081	struct ip_tunnel *nt;
1082	struct net *net = dev_net(dev);
1083	struct ip_tunnel_net *itn;
1084	int mtu;
1085	int err;
1086
1087	nt = netdev_priv(dev);
1088	itn = net_generic(net, nt->ip_tnl_net_id);
1089
1090	if (nt->collect_md) {
1091		if (rtnl_dereference(itn->collect_md_tun))
1092			return -EEXIST;
1093	} else {
1094		if (ip_tunnel_find(itn, p, dev->type))
1095			return -EEXIST;
1096	}
1097
1098	nt->net = net;
1099	nt->parms = *p;
1100	nt->fwmark = fwmark;
1101	err = register_netdevice(dev);
1102	if (err)
1103		goto err_register_netdevice;
1104
1105	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1106		eth_hw_addr_random(dev);
1107
1108	mtu = ip_tunnel_bind_dev(dev);
1109	if (tb[IFLA_MTU]) {
1110		unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen;
1111
1112		mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU,
1113			    (unsigned int)(max - sizeof(struct iphdr)));
1114	}
1115
1116	err = dev_set_mtu(dev, mtu);
1117	if (err)
1118		goto err_dev_set_mtu;
1119
1120	ip_tunnel_add(itn, nt);
1121	return 0;
1122
1123err_dev_set_mtu:
1124	unregister_netdevice(dev);
1125err_register_netdevice:
1126	return err;
1127}
1128EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1129
1130int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1131			 struct ip_tunnel_parm *p, __u32 fwmark)
1132{
1133	struct ip_tunnel *t;
1134	struct ip_tunnel *tunnel = netdev_priv(dev);
1135	struct net *net = tunnel->net;
1136	struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1137
1138	if (dev == itn->fb_tunnel_dev)
1139		return -EINVAL;
1140
1141	t = ip_tunnel_find(itn, p, dev->type);
1142
1143	if (t) {
1144		if (t->dev != dev)
1145			return -EEXIST;
1146	} else {
1147		t = tunnel;
1148
1149		if (dev->type != ARPHRD_ETHER) {
1150			unsigned int nflags = 0;
1151
1152			if (ipv4_is_multicast(p->iph.daddr))
1153				nflags = IFF_BROADCAST;
1154			else if (p->iph.daddr)
1155				nflags = IFF_POINTOPOINT;
1156
1157			if ((dev->flags ^ nflags) &
1158			    (IFF_POINTOPOINT | IFF_BROADCAST))
1159				return -EINVAL;
1160		}
1161	}
1162
1163	ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1164	return 0;
1165}
1166EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1167
1168int ip_tunnel_init(struct net_device *dev)
1169{
1170	struct ip_tunnel *tunnel = netdev_priv(dev);
1171	struct iphdr *iph = &tunnel->parms.iph;
1172	int err;
1173
1174	dev->needs_free_netdev = true;
1175	dev->priv_destructor = ip_tunnel_dev_free;
1176	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1177	if (!dev->tstats)
1178		return -ENOMEM;
1179
1180	err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1181	if (err) {
1182		free_percpu(dev->tstats);
1183		return err;
1184	}
1185
1186	err = gro_cells_init(&tunnel->gro_cells, dev);
1187	if (err) {
1188		dst_cache_destroy(&tunnel->dst_cache);
1189		free_percpu(dev->tstats);
1190		return err;
1191	}
1192
1193	tunnel->dev = dev;
1194	tunnel->net = dev_net(dev);
1195	strcpy(tunnel->parms.name, dev->name);
1196	iph->version		= 4;
1197	iph->ihl		= 5;
1198
1199	if (tunnel->collect_md) {
1200		dev->features |= NETIF_F_NETNS_LOCAL;
1201		netif_keep_dst(dev);
1202	}
1203	return 0;
1204}
1205EXPORT_SYMBOL_GPL(ip_tunnel_init);
1206
1207void ip_tunnel_uninit(struct net_device *dev)
1208{
1209	struct ip_tunnel *tunnel = netdev_priv(dev);
1210	struct net *net = tunnel->net;
1211	struct ip_tunnel_net *itn;
1212
1213	itn = net_generic(net, tunnel->ip_tnl_net_id);
1214	/* fb_tunnel_dev will be unregisted in net-exit call. */
1215	if (itn->fb_tunnel_dev != dev)
1216		ip_tunnel_del(itn, netdev_priv(dev));
1217
1218	dst_cache_reset(&tunnel->dst_cache);
1219}
1220EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1221
1222/* Do least required initialization, rest of init is done in tunnel_init call */
1223void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1224{
1225	struct ip_tunnel *tunnel = netdev_priv(dev);
1226	tunnel->ip_tnl_net_id = net_id;
1227}
1228EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1229
1230MODULE_LICENSE("GPL");
v3.15
   1/*
   2 * Copyright (c) 2013 Nicira, Inc.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of version 2 of the GNU General Public
   6 * License as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public License
  14 * along with this program; if not, write to the Free Software
  15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16 * 02110-1301, USA
  17 */
  18
  19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  20
  21#include <linux/capability.h>
  22#include <linux/module.h>
  23#include <linux/types.h>
  24#include <linux/kernel.h>
  25#include <linux/slab.h>
  26#include <linux/uaccess.h>
  27#include <linux/skbuff.h>
  28#include <linux/netdevice.h>
  29#include <linux/in.h>
  30#include <linux/tcp.h>
  31#include <linux/udp.h>
  32#include <linux/if_arp.h>
  33#include <linux/mroute.h>
  34#include <linux/init.h>
  35#include <linux/in6.h>
  36#include <linux/inetdevice.h>
  37#include <linux/igmp.h>
  38#include <linux/netfilter_ipv4.h>
  39#include <linux/etherdevice.h>
  40#include <linux/if_ether.h>
  41#include <linux/if_vlan.h>
  42#include <linux/rculist.h>
  43#include <linux/err.h>
  44
  45#include <net/sock.h>
  46#include <net/ip.h>
  47#include <net/icmp.h>
  48#include <net/protocol.h>
  49#include <net/ip_tunnels.h>
  50#include <net/arp.h>
  51#include <net/checksum.h>
  52#include <net/dsfield.h>
  53#include <net/inet_ecn.h>
  54#include <net/xfrm.h>
  55#include <net/net_namespace.h>
  56#include <net/netns/generic.h>
  57#include <net/rtnetlink.h>
 
 
  58
  59#if IS_ENABLED(CONFIG_IPV6)
  60#include <net/ipv6.h>
  61#include <net/ip6_fib.h>
  62#include <net/ip6_route.h>
  63#endif
  64
  65static unsigned int ip_tunnel_hash(__be32 key, __be32 remote)
  66{
  67	return hash_32((__force u32)key ^ (__force u32)remote,
  68			 IP_TNL_HASH_BITS);
  69}
  70
  71static void __tunnel_dst_set(struct ip_tunnel_dst *idst,
  72			     struct dst_entry *dst)
  73{
  74	struct dst_entry *old_dst;
  75
  76	if (dst) {
  77		if (dst->flags & DST_NOCACHE)
  78			dst = NULL;
  79		else
  80			dst_clone(dst);
  81	}
  82	old_dst = xchg((__force struct dst_entry **)&idst->dst, dst);
  83	dst_release(old_dst);
  84}
  85
  86static void tunnel_dst_set(struct ip_tunnel *t, struct dst_entry *dst)
  87{
  88	__tunnel_dst_set(this_cpu_ptr(t->dst_cache), dst);
  89}
  90
  91static void tunnel_dst_reset(struct ip_tunnel *t)
  92{
  93	tunnel_dst_set(t, NULL);
  94}
  95
  96void ip_tunnel_dst_reset_all(struct ip_tunnel *t)
  97{
  98	int i;
  99
 100	for_each_possible_cpu(i)
 101		__tunnel_dst_set(per_cpu_ptr(t->dst_cache, i), NULL);
 102}
 103EXPORT_SYMBOL(ip_tunnel_dst_reset_all);
 104
 105static struct rtable *tunnel_rtable_get(struct ip_tunnel *t, u32 cookie)
 106{
 107	struct dst_entry *dst;
 108
 109	rcu_read_lock();
 110	dst = rcu_dereference(this_cpu_ptr(t->dst_cache)->dst);
 111	if (dst) {
 112		if (dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 113			rcu_read_unlock();
 114			tunnel_dst_reset(t);
 115			return NULL;
 116		}
 117		dst_hold(dst);
 118	}
 119	rcu_read_unlock();
 120	return (struct rtable *)dst;
 121}
 122
 123static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p,
 124				__be16 flags, __be32 key)
 125{
 126	if (p->i_flags & TUNNEL_KEY) {
 127		if (flags & TUNNEL_KEY)
 128			return key == p->i_key;
 129		else
 130			/* key expected, none present */
 131			return false;
 132	} else
 133		return !(flags & TUNNEL_KEY);
 134}
 135
 136/* Fallback tunnel: no source, no destination, no key, no options
 137
 138   Tunnel hash table:
 139   We require exact key match i.e. if a key is present in packet
 140   it will match only tunnel with the same key; if it is not present,
 141   it will match only keyless tunnel.
 142
 143   All keysless packets, if not matched configured keyless tunnels
 144   will match fallback tunnel.
 145   Given src, dst and key, find appropriate for input tunnel.
 146*/
 147struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 148				   int link, __be16 flags,
 149				   __be32 remote, __be32 local,
 150				   __be32 key)
 151{
 152	unsigned int hash;
 153	struct ip_tunnel *t, *cand = NULL;
 154	struct hlist_head *head;
 155
 156	hash = ip_tunnel_hash(key, remote);
 157	head = &itn->tunnels[hash];
 158
 159	hlist_for_each_entry_rcu(t, head, hash_node) {
 160		if (local != t->parms.iph.saddr ||
 161		    remote != t->parms.iph.daddr ||
 162		    !(t->dev->flags & IFF_UP))
 163			continue;
 164
 165		if (!ip_tunnel_key_match(&t->parms, flags, key))
 166			continue;
 167
 168		if (t->parms.link == link)
 169			return t;
 170		else
 171			cand = t;
 172	}
 173
 174	hlist_for_each_entry_rcu(t, head, hash_node) {
 175		if (remote != t->parms.iph.daddr ||
 
 176		    !(t->dev->flags & IFF_UP))
 177			continue;
 178
 179		if (!ip_tunnel_key_match(&t->parms, flags, key))
 180			continue;
 181
 182		if (t->parms.link == link)
 183			return t;
 184		else if (!cand)
 185			cand = t;
 186	}
 187
 188	hash = ip_tunnel_hash(key, 0);
 189	head = &itn->tunnels[hash];
 190
 191	hlist_for_each_entry_rcu(t, head, hash_node) {
 192		if ((local != t->parms.iph.saddr &&
 193		     (local != t->parms.iph.daddr ||
 194		      !ipv4_is_multicast(local))) ||
 195		    !(t->dev->flags & IFF_UP))
 
 196			continue;
 197
 198		if (!ip_tunnel_key_match(&t->parms, flags, key))
 199			continue;
 200
 201		if (t->parms.link == link)
 202			return t;
 203		else if (!cand)
 204			cand = t;
 205	}
 206
 207	if (flags & TUNNEL_NO_KEY)
 208		goto skip_key_lookup;
 209
 210	hlist_for_each_entry_rcu(t, head, hash_node) {
 211		if (t->parms.i_key != key ||
 
 
 212		    !(t->dev->flags & IFF_UP))
 213			continue;
 214
 215		if (t->parms.link == link)
 216			return t;
 217		else if (!cand)
 218			cand = t;
 219	}
 220
 221skip_key_lookup:
 222	if (cand)
 223		return cand;
 224
 
 
 
 
 225	if (itn->fb_tunnel_dev && itn->fb_tunnel_dev->flags & IFF_UP)
 226		return netdev_priv(itn->fb_tunnel_dev);
 227
 228
 229	return NULL;
 230}
 231EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
 232
 233static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn,
 234				    struct ip_tunnel_parm *parms)
 235{
 236	unsigned int h;
 237	__be32 remote;
 238	__be32 i_key = parms->i_key;
 239
 240	if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr))
 241		remote = parms->iph.daddr;
 242	else
 243		remote = 0;
 244
 245	if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI))
 246		i_key = 0;
 247
 248	h = ip_tunnel_hash(i_key, remote);
 249	return &itn->tunnels[h];
 250}
 251
 252static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t)
 253{
 254	struct hlist_head *head = ip_bucket(itn, &t->parms);
 255
 
 
 256	hlist_add_head_rcu(&t->hash_node, head);
 257}
 258
 259static void ip_tunnel_del(struct ip_tunnel *t)
 260{
 
 
 261	hlist_del_init_rcu(&t->hash_node);
 262}
 263
 264static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
 265					struct ip_tunnel_parm *parms,
 266					int type)
 267{
 268	__be32 remote = parms->iph.daddr;
 269	__be32 local = parms->iph.saddr;
 270	__be32 key = parms->i_key;
 
 271	int link = parms->link;
 272	struct ip_tunnel *t = NULL;
 273	struct hlist_head *head = ip_bucket(itn, parms);
 274
 275	hlist_for_each_entry_rcu(t, head, hash_node) {
 276		if (local == t->parms.iph.saddr &&
 277		    remote == t->parms.iph.daddr &&
 278		    key == t->parms.i_key &&
 279		    link == t->parms.link &&
 280		    type == t->dev->type)
 
 281			break;
 282	}
 283	return t;
 284}
 285
 286static struct net_device *__ip_tunnel_create(struct net *net,
 287					     const struct rtnl_link_ops *ops,
 288					     struct ip_tunnel_parm *parms)
 289{
 290	int err;
 291	struct ip_tunnel *tunnel;
 292	struct net_device *dev;
 293	char name[IFNAMSIZ];
 294
 295	if (parms->name[0])
 
 
 
 296		strlcpy(name, parms->name, IFNAMSIZ);
 297	else {
 298		if (strlen(ops->kind) > (IFNAMSIZ - 3)) {
 299			err = -E2BIG;
 300			goto failed;
 301		}
 302		strlcpy(name, ops->kind, IFNAMSIZ);
 303		strncat(name, "%d", 2);
 304	}
 305
 306	ASSERT_RTNL();
 307	dev = alloc_netdev(ops->priv_size, name, ops->setup);
 308	if (!dev) {
 309		err = -ENOMEM;
 310		goto failed;
 311	}
 312	dev_net_set(dev, net);
 313
 314	dev->rtnl_link_ops = ops;
 315
 316	tunnel = netdev_priv(dev);
 317	tunnel->parms = *parms;
 318	tunnel->net = net;
 319
 320	err = register_netdevice(dev);
 321	if (err)
 322		goto failed_free;
 323
 324	return dev;
 325
 326failed_free:
 327	free_netdev(dev);
 328failed:
 329	return ERR_PTR(err);
 330}
 331
 332static inline void init_tunnel_flow(struct flowi4 *fl4,
 333				    int proto,
 334				    __be32 daddr, __be32 saddr,
 335				    __be32 key, __u8 tos, int oif)
 336{
 337	memset(fl4, 0, sizeof(*fl4));
 338	fl4->flowi4_oif = oif;
 339	fl4->daddr = daddr;
 340	fl4->saddr = saddr;
 341	fl4->flowi4_tos = tos;
 342	fl4->flowi4_proto = proto;
 343	fl4->fl4_gre_key = key;
 344}
 345
 346static int ip_tunnel_bind_dev(struct net_device *dev)
 347{
 348	struct net_device *tdev = NULL;
 349	struct ip_tunnel *tunnel = netdev_priv(dev);
 350	const struct iphdr *iph;
 351	int hlen = LL_MAX_HEADER;
 352	int mtu = ETH_DATA_LEN;
 353	int t_hlen = tunnel->hlen + sizeof(struct iphdr);
 354
 355	iph = &tunnel->parms.iph;
 356
 357	/* Guess output device to choose reasonable mtu and needed_headroom */
 358	if (iph->daddr) {
 359		struct flowi4 fl4;
 360		struct rtable *rt;
 361
 362		init_tunnel_flow(&fl4, iph->protocol, iph->daddr,
 363				 iph->saddr, tunnel->parms.o_key,
 364				 RT_TOS(iph->tos), tunnel->parms.link);
 
 365		rt = ip_route_output_key(tunnel->net, &fl4);
 366
 367		if (!IS_ERR(rt)) {
 368			tdev = rt->dst.dev;
 369			tunnel_dst_set(tunnel, &rt->dst);
 370			ip_rt_put(rt);
 371		}
 372		if (dev->type != ARPHRD_ETHER)
 373			dev->flags |= IFF_POINTOPOINT;
 
 
 374	}
 375
 376	if (!tdev && tunnel->parms.link)
 377		tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
 378
 379	if (tdev) {
 380		hlen = tdev->hard_header_len + tdev->needed_headroom;
 381		mtu = tdev->mtu;
 382	}
 383	dev->iflink = tunnel->parms.link;
 384
 385	dev->needed_headroom = t_hlen + hlen;
 386	mtu -= (dev->hard_header_len + t_hlen);
 387
 388	if (mtu < 68)
 389		mtu = 68;
 390
 391	return mtu;
 392}
 393
 394static struct ip_tunnel *ip_tunnel_create(struct net *net,
 395					  struct ip_tunnel_net *itn,
 396					  struct ip_tunnel_parm *parms)
 397{
 398	struct ip_tunnel *nt, *fbt;
 399	struct net_device *dev;
 
 
 
 400
 401	BUG_ON(!itn->fb_tunnel_dev);
 402	fbt = netdev_priv(itn->fb_tunnel_dev);
 403	dev = __ip_tunnel_create(net, itn->fb_tunnel_dev->rtnl_link_ops, parms);
 404	if (IS_ERR(dev))
 405		return ERR_CAST(dev);
 406
 407	dev->mtu = ip_tunnel_bind_dev(dev);
 
 
 
 408
 409	nt = netdev_priv(dev);
 
 
 
 410	ip_tunnel_add(itn, nt);
 411	return nt;
 
 
 
 
 412}
 413
 414int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 415		  const struct tnl_ptk_info *tpi, bool log_ecn_error)
 
 416{
 417	struct pcpu_sw_netstats *tstats;
 418	const struct iphdr *iph = ip_hdr(skb);
 419	int err;
 420
 421#ifdef CONFIG_NET_IPGRE_BROADCAST
 422	if (ipv4_is_multicast(iph->daddr)) {
 423		tunnel->dev->stats.multicast++;
 424		skb->pkt_type = PACKET_BROADCAST;
 425	}
 426#endif
 427
 428	if ((!(tpi->flags&TUNNEL_CSUM) &&  (tunnel->parms.i_flags&TUNNEL_CSUM)) ||
 429	     ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) {
 430		tunnel->dev->stats.rx_crc_errors++;
 431		tunnel->dev->stats.rx_errors++;
 432		goto drop;
 433	}
 434
 435	if (tunnel->parms.i_flags&TUNNEL_SEQ) {
 436		if (!(tpi->flags&TUNNEL_SEQ) ||
 437		    (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 438			tunnel->dev->stats.rx_fifo_errors++;
 439			tunnel->dev->stats.rx_errors++;
 440			goto drop;
 441		}
 442		tunnel->i_seqno = ntohl(tpi->seq) + 1;
 443	}
 444
 445	skb_reset_network_header(skb);
 446
 447	err = IP_ECN_decapsulate(iph, skb);
 448	if (unlikely(err)) {
 449		if (log_ecn_error)
 450			net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
 451					&iph->saddr, iph->tos);
 452		if (err > 1) {
 453			++tunnel->dev->stats.rx_frame_errors;
 454			++tunnel->dev->stats.rx_errors;
 455			goto drop;
 456		}
 457	}
 458
 459	tstats = this_cpu_ptr(tunnel->dev->tstats);
 460	u64_stats_update_begin(&tstats->syncp);
 461	tstats->rx_packets++;
 462	tstats->rx_bytes += skb->len;
 463	u64_stats_update_end(&tstats->syncp);
 464
 465	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 466
 467	if (tunnel->dev->type == ARPHRD_ETHER) {
 468		skb->protocol = eth_type_trans(skb, tunnel->dev);
 469		skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 470	} else {
 471		skb->dev = tunnel->dev;
 472	}
 473
 
 
 
 474	gro_cells_receive(&tunnel->gro_cells, skb);
 475	return 0;
 476
 477drop:
 
 
 478	kfree_skb(skb);
 479	return 0;
 480}
 481EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
 482
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 483static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
 484			    struct rtable *rt, __be16 df)
 
 485{
 486	struct ip_tunnel *tunnel = netdev_priv(dev);
 487	int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len;
 488	int mtu;
 489
 490	if (df)
 491		mtu = dst_mtu(&rt->dst) - dev->hard_header_len
 492					- sizeof(struct iphdr) - tunnel->hlen;
 493	else
 494		mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
 495
 496	if (skb_dst(skb))
 497		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
 498
 499	if (skb->protocol == htons(ETH_P_IP)) {
 500		if (!skb_is_gso(skb) &&
 501		    (df & htons(IP_DF)) && mtu < pkt_size) {
 
 502			memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 503			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
 504			return -E2BIG;
 505		}
 506	}
 507#if IS_ENABLED(CONFIG_IPV6)
 508	else if (skb->protocol == htons(ETH_P_IPV6)) {
 509		struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
 510
 511		if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
 512			   mtu >= IPV6_MIN_MTU) {
 513			if ((tunnel->parms.iph.daddr &&
 514			    !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
 515			    rt6->rt6i_dst.plen == 128) {
 516				rt6->rt6i_flags |= RTF_MODIFIED;
 517				dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
 518			}
 519		}
 520
 521		if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
 522					mtu < pkt_size) {
 523			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 524			return -E2BIG;
 525		}
 526	}
 527#endif
 528	return 0;
 529}
 530
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 531void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 532		    const struct iphdr *tnl_params, const u8 protocol)
 533{
 534	struct ip_tunnel *tunnel = netdev_priv(dev);
 535	const struct iphdr *inner_iph;
 536	struct flowi4 fl4;
 537	u8     tos, ttl;
 538	__be16 df;
 539	struct rtable *rt;		/* Route to the other host */
 540	unsigned int max_headroom;	/* The extra header space needed */
 541	__be32 dst;
 542	int err;
 543	bool connected;
 544
 545	inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
 546	connected = (tunnel->parms.iph.daddr != 0);
 547
 
 
 548	dst = tnl_params->daddr;
 549	if (dst == 0) {
 550		/* NBMA tunnel */
 551
 552		if (skb_dst(skb) == NULL) {
 553			dev->stats.tx_fifo_errors++;
 554			goto tx_error;
 555		}
 556
 557		if (skb->protocol == htons(ETH_P_IP)) {
 558			rt = skb_rtable(skb);
 559			dst = rt_nexthop(rt, inner_iph->daddr);
 560		}
 561#if IS_ENABLED(CONFIG_IPV6)
 562		else if (skb->protocol == htons(ETH_P_IPV6)) {
 563			const struct in6_addr *addr6;
 564			struct neighbour *neigh;
 565			bool do_tx_error_icmp;
 566			int addr_type;
 567
 568			neigh = dst_neigh_lookup(skb_dst(skb),
 569						 &ipv6_hdr(skb)->daddr);
 570			if (neigh == NULL)
 571				goto tx_error;
 572
 573			addr6 = (const struct in6_addr *)&neigh->primary_key;
 574			addr_type = ipv6_addr_type(addr6);
 575
 576			if (addr_type == IPV6_ADDR_ANY) {
 577				addr6 = &ipv6_hdr(skb)->daddr;
 578				addr_type = ipv6_addr_type(addr6);
 579			}
 580
 581			if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
 582				do_tx_error_icmp = true;
 583			else {
 584				do_tx_error_icmp = false;
 585				dst = addr6->s6_addr32[3];
 586			}
 587			neigh_release(neigh);
 588			if (do_tx_error_icmp)
 589				goto tx_error_icmp;
 590		}
 591#endif
 592		else
 593			goto tx_error;
 594
 595		connected = false;
 596	}
 597
 598	tos = tnl_params->tos;
 599	if (tos & 0x1) {
 600		tos &= ~0x1;
 601		if (skb->protocol == htons(ETH_P_IP)) {
 602			tos = inner_iph->tos;
 603			connected = false;
 604		} else if (skb->protocol == htons(ETH_P_IPV6)) {
 605			tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
 606			connected = false;
 607		}
 608	}
 609
 610	init_tunnel_flow(&fl4, protocol, dst, tnl_params->saddr,
 611			 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link);
 
 612
 613	rt = connected ? tunnel_rtable_get(tunnel, 0) : NULL;
 
 
 
 
 614
 615	if (!rt) {
 616		rt = ip_route_output_key(tunnel->net, &fl4);
 617
 618		if (IS_ERR(rt)) {
 619			dev->stats.tx_carrier_errors++;
 620			goto tx_error;
 621		}
 622		if (connected)
 623			tunnel_dst_set(tunnel, &rt->dst);
 
 624	}
 625
 626	if (rt->dst.dev == dev) {
 627		ip_rt_put(rt);
 628		dev->stats.collisions++;
 629		goto tx_error;
 630	}
 631
 632	if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off)) {
 633		ip_rt_put(rt);
 634		goto tx_error;
 635	}
 636
 637	if (tunnel->err_count > 0) {
 638		if (time_before(jiffies,
 639				tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
 640			tunnel->err_count--;
 641
 642			memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 643			dst_link_failure(skb);
 644		} else
 645			tunnel->err_count = 0;
 646	}
 647
 648	tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
 649	ttl = tnl_params->ttl;
 650	if (ttl == 0) {
 651		if (skb->protocol == htons(ETH_P_IP))
 652			ttl = inner_iph->ttl;
 653#if IS_ENABLED(CONFIG_IPV6)
 654		else if (skb->protocol == htons(ETH_P_IPV6))
 655			ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
 656#endif
 657		else
 658			ttl = ip4_dst_hoplimit(&rt->dst);
 659	}
 660
 661	df = tnl_params->frag_off;
 662	if (skb->protocol == htons(ETH_P_IP))
 663		df |= (inner_iph->frag_off&htons(IP_DF));
 664
 665	max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
 666			+ rt->dst.header_len;
 667	if (max_headroom > dev->needed_headroom)
 668		dev->needed_headroom = max_headroom;
 669
 670	if (skb_cow_head(skb, dev->needed_headroom)) {
 
 671		dev->stats.tx_dropped++;
 672		kfree_skb(skb);
 673		return;
 674	}
 675
 676	err = iptunnel_xmit(skb->sk, rt, skb, fl4.saddr, fl4.daddr, protocol,
 677			    tos, ttl, df, !net_eq(tunnel->net, dev_net(dev)));
 678	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
 679
 680	return;
 681
 682#if IS_ENABLED(CONFIG_IPV6)
 683tx_error_icmp:
 684	dst_link_failure(skb);
 685#endif
 686tx_error:
 687	dev->stats.tx_errors++;
 688	kfree_skb(skb);
 689}
 690EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
 691
 692static void ip_tunnel_update(struct ip_tunnel_net *itn,
 693			     struct ip_tunnel *t,
 694			     struct net_device *dev,
 695			     struct ip_tunnel_parm *p,
 696			     bool set_mtu)
 
 697{
 698	ip_tunnel_del(t);
 699	t->parms.iph.saddr = p->iph.saddr;
 700	t->parms.iph.daddr = p->iph.daddr;
 701	t->parms.i_key = p->i_key;
 702	t->parms.o_key = p->o_key;
 703	if (dev->type != ARPHRD_ETHER) {
 704		memcpy(dev->dev_addr, &p->iph.saddr, 4);
 705		memcpy(dev->broadcast, &p->iph.daddr, 4);
 706	}
 707	ip_tunnel_add(itn, t);
 708
 709	t->parms.iph.ttl = p->iph.ttl;
 710	t->parms.iph.tos = p->iph.tos;
 711	t->parms.iph.frag_off = p->iph.frag_off;
 712
 713	if (t->parms.link != p->link) {
 714		int mtu;
 715
 716		t->parms.link = p->link;
 
 717		mtu = ip_tunnel_bind_dev(dev);
 718		if (set_mtu)
 719			dev->mtu = mtu;
 720	}
 721	ip_tunnel_dst_reset_all(t);
 722	netdev_state_change(dev);
 723}
 724
 725int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
 726{
 727	int err = 0;
 728	struct ip_tunnel *t = netdev_priv(dev);
 729	struct net *net = t->net;
 730	struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
 731
 732	BUG_ON(!itn->fb_tunnel_dev);
 733	switch (cmd) {
 734	case SIOCGETTUNNEL:
 735		if (dev == itn->fb_tunnel_dev) {
 736			t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
 737			if (t == NULL)
 738				t = netdev_priv(dev);
 739		}
 740		memcpy(p, &t->parms, sizeof(*p));
 741		break;
 742
 743	case SIOCADDTUNNEL:
 744	case SIOCCHGTUNNEL:
 745		err = -EPERM;
 746		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 747			goto done;
 748		if (p->iph.ttl)
 749			p->iph.frag_off |= htons(IP_DF);
 750		if (!(p->i_flags&TUNNEL_KEY))
 751			p->i_key = 0;
 752		if (!(p->o_flags&TUNNEL_KEY))
 753			p->o_key = 0;
 754
 755		t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
 756
 757		if (!t && (cmd == SIOCADDTUNNEL)) {
 758			t = ip_tunnel_create(net, itn, p);
 759			if (IS_ERR(t)) {
 760				err = PTR_ERR(t);
 
 
 761				break;
 762			}
 
 
 
 763		}
 764		if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
 765			if (t != NULL) {
 766				if (t->dev != dev) {
 767					err = -EEXIST;
 768					break;
 769				}
 770			} else {
 771				unsigned int nflags = 0;
 772
 773				if (ipv4_is_multicast(p->iph.daddr))
 774					nflags = IFF_BROADCAST;
 775				else if (p->iph.daddr)
 776					nflags = IFF_POINTOPOINT;
 777
 778				if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
 779					err = -EINVAL;
 780					break;
 781				}
 782
 783				t = netdev_priv(dev);
 784			}
 785		}
 786
 787		if (t) {
 788			err = 0;
 789			ip_tunnel_update(itn, t, dev, p, true);
 790		} else {
 791			err = -ENOENT;
 792		}
 793		break;
 794
 795	case SIOCDELTUNNEL:
 796		err = -EPERM;
 797		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 798			goto done;
 799
 800		if (dev == itn->fb_tunnel_dev) {
 801			err = -ENOENT;
 802			t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
 803			if (t == NULL)
 804				goto done;
 805			err = -EPERM;
 806			if (t == netdev_priv(itn->fb_tunnel_dev))
 807				goto done;
 808			dev = t->dev;
 809		}
 810		unregister_netdevice(dev);
 811		err = 0;
 812		break;
 813
 814	default:
 815		err = -EINVAL;
 816	}
 817
 818done:
 819	return err;
 820}
 821EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
 822
 823int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
 824{
 825	struct ip_tunnel *tunnel = netdev_priv(dev);
 826	int t_hlen = tunnel->hlen + sizeof(struct iphdr);
 
 827
 828	if (new_mtu < 68 ||
 829	    new_mtu > 0xFFF8 - dev->hard_header_len - t_hlen)
 830		return -EINVAL;
 
 
 
 
 
 
 
 
 831	dev->mtu = new_mtu;
 832	return 0;
 833}
 
 
 
 
 
 
 834EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
 835
 836static void ip_tunnel_dev_free(struct net_device *dev)
 837{
 838	struct ip_tunnel *tunnel = netdev_priv(dev);
 839
 840	gro_cells_destroy(&tunnel->gro_cells);
 841	free_percpu(tunnel->dst_cache);
 842	free_percpu(dev->tstats);
 843	free_netdev(dev);
 844}
 845
 846void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
 847{
 848	struct ip_tunnel *tunnel = netdev_priv(dev);
 849	struct ip_tunnel_net *itn;
 850
 851	itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
 852
 853	if (itn->fb_tunnel_dev != dev) {
 854		ip_tunnel_del(netdev_priv(dev));
 855		unregister_netdevice_queue(dev, head);
 856	}
 857}
 858EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
 859
 860int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 861				  struct rtnl_link_ops *ops, char *devname)
 862{
 863	struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
 864	struct ip_tunnel_parm parms;
 865	unsigned int i;
 866
 
 867	for (i = 0; i < IP_TNL_HASH_SIZE; i++)
 868		INIT_HLIST_HEAD(&itn->tunnels[i]);
 869
 870	if (!ops) {
 
 
 
 
 871		itn->fb_tunnel_dev = NULL;
 872		return 0;
 873	}
 874
 875	memset(&parms, 0, sizeof(parms));
 876	if (devname)
 877		strlcpy(parms.name, devname, IFNAMSIZ);
 878
 879	rtnl_lock();
 880	itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
 881	/* FB netdevice is special: we have one, and only one per netns.
 882	 * Allowing to move it to another netns is clearly unsafe.
 883	 */
 884	if (!IS_ERR(itn->fb_tunnel_dev)) {
 885		itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
 886		itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
 887		ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
 
 888	}
 889	rtnl_unlock();
 890
 891	return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
 892}
 893EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
 894
 895static void ip_tunnel_destroy(struct ip_tunnel_net *itn, struct list_head *head,
 
 896			      struct rtnl_link_ops *ops)
 897{
 898	struct net *net = dev_net(itn->fb_tunnel_dev);
 899	struct net_device *dev, *aux;
 900	int h;
 901
 902	for_each_netdev_safe(net, dev, aux)
 903		if (dev->rtnl_link_ops == ops)
 904			unregister_netdevice_queue(dev, head);
 905
 906	for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
 907		struct ip_tunnel *t;
 908		struct hlist_node *n;
 909		struct hlist_head *thead = &itn->tunnels[h];
 910
 911		hlist_for_each_entry_safe(t, n, thead, hash_node)
 912			/* If dev is in the same netns, it has already
 913			 * been added to the list by the previous loop.
 914			 */
 915			if (!net_eq(dev_net(t->dev), net))
 916				unregister_netdevice_queue(t->dev, head);
 917	}
 918}
 919
 920void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops)
 
 921{
 
 
 922	LIST_HEAD(list);
 923
 924	rtnl_lock();
 925	ip_tunnel_destroy(itn, &list, ops);
 
 
 
 926	unregister_netdevice_many(&list);
 927	rtnl_unlock();
 928}
 929EXPORT_SYMBOL_GPL(ip_tunnel_delete_net);
 930
 931int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
 932		      struct ip_tunnel_parm *p)
 933{
 934	struct ip_tunnel *nt;
 935	struct net *net = dev_net(dev);
 936	struct ip_tunnel_net *itn;
 937	int mtu;
 938	int err;
 939
 940	nt = netdev_priv(dev);
 941	itn = net_generic(net, nt->ip_tnl_net_id);
 942
 943	if (ip_tunnel_find(itn, p, dev->type))
 944		return -EEXIST;
 
 
 
 
 
 945
 946	nt->net = net;
 947	nt->parms = *p;
 
 948	err = register_netdevice(dev);
 949	if (err)
 950		goto out;
 951
 952	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
 953		eth_hw_addr_random(dev);
 954
 955	mtu = ip_tunnel_bind_dev(dev);
 956	if (!tb[IFLA_MTU])
 957		dev->mtu = mtu;
 
 
 
 
 
 
 
 
 958
 959	ip_tunnel_add(itn, nt);
 
 960
 961out:
 
 
 962	return err;
 963}
 964EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
 965
 966int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
 967			 struct ip_tunnel_parm *p)
 968{
 969	struct ip_tunnel *t;
 970	struct ip_tunnel *tunnel = netdev_priv(dev);
 971	struct net *net = tunnel->net;
 972	struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
 973
 974	if (dev == itn->fb_tunnel_dev)
 975		return -EINVAL;
 976
 977	t = ip_tunnel_find(itn, p, dev->type);
 978
 979	if (t) {
 980		if (t->dev != dev)
 981			return -EEXIST;
 982	} else {
 983		t = tunnel;
 984
 985		if (dev->type != ARPHRD_ETHER) {
 986			unsigned int nflags = 0;
 987
 988			if (ipv4_is_multicast(p->iph.daddr))
 989				nflags = IFF_BROADCAST;
 990			else if (p->iph.daddr)
 991				nflags = IFF_POINTOPOINT;
 992
 993			if ((dev->flags ^ nflags) &
 994			    (IFF_POINTOPOINT | IFF_BROADCAST))
 995				return -EINVAL;
 996		}
 997	}
 998
 999	ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU]);
1000	return 0;
1001}
1002EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1003
1004int ip_tunnel_init(struct net_device *dev)
1005{
1006	struct ip_tunnel *tunnel = netdev_priv(dev);
1007	struct iphdr *iph = &tunnel->parms.iph;
1008	int err;
1009
1010	dev->destructor	= ip_tunnel_dev_free;
 
1011	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1012	if (!dev->tstats)
1013		return -ENOMEM;
1014
1015	tunnel->dst_cache = alloc_percpu(struct ip_tunnel_dst);
1016	if (!tunnel->dst_cache) {
1017		free_percpu(dev->tstats);
1018		return -ENOMEM;
1019	}
1020
1021	err = gro_cells_init(&tunnel->gro_cells, dev);
1022	if (err) {
1023		free_percpu(tunnel->dst_cache);
1024		free_percpu(dev->tstats);
1025		return err;
1026	}
1027
1028	tunnel->dev = dev;
1029	tunnel->net = dev_net(dev);
1030	strcpy(tunnel->parms.name, dev->name);
1031	iph->version		= 4;
1032	iph->ihl		= 5;
1033
 
 
 
 
1034	return 0;
1035}
1036EXPORT_SYMBOL_GPL(ip_tunnel_init);
1037
1038void ip_tunnel_uninit(struct net_device *dev)
1039{
1040	struct ip_tunnel *tunnel = netdev_priv(dev);
1041	struct net *net = tunnel->net;
1042	struct ip_tunnel_net *itn;
1043
1044	itn = net_generic(net, tunnel->ip_tnl_net_id);
1045	/* fb_tunnel_dev will be unregisted in net-exit call. */
1046	if (itn->fb_tunnel_dev != dev)
1047		ip_tunnel_del(netdev_priv(dev));
1048
1049	ip_tunnel_dst_reset_all(tunnel);
1050}
1051EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1052
1053/* Do least required initialization, rest of init is done in tunnel_init call */
1054void ip_tunnel_setup(struct net_device *dev, int net_id)
1055{
1056	struct ip_tunnel *tunnel = netdev_priv(dev);
1057	tunnel->ip_tnl_net_id = net_id;
1058}
1059EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1060
1061MODULE_LICENSE("GPL");