Linux Audio

Check our new training course

In-person Linux kernel drivers training

Jun 16-20, 2025
Register
Loading...
v3.1
 
   1/*
   2 *	IPv6 tunneling device
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Ville Nuorvala		<vnuorval@tcs.hut.fi>
   7 *	Yasuyuki Kozakai	<kozakai@linux-ipv6.org>
   8 *
   9 *      Based on:
  10 *      linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
  11 *
  12 *      RFC 2473
  13 *
  14 *	This program is free software; you can redistribute it and/or
  15 *      modify it under the terms of the GNU General Public License
  16 *      as published by the Free Software Foundation; either version
  17 *      2 of the License, or (at your option) any later version.
  18 *
  19 */
  20
 
 
  21#include <linux/module.h>
  22#include <linux/capability.h>
  23#include <linux/errno.h>
  24#include <linux/types.h>
  25#include <linux/sockios.h>
  26#include <linux/icmp.h>
  27#include <linux/if.h>
  28#include <linux/in.h>
  29#include <linux/ip.h>
  30#include <linux/if_tunnel.h>
  31#include <linux/net.h>
  32#include <linux/in6.h>
  33#include <linux/netdevice.h>
  34#include <linux/if_arp.h>
  35#include <linux/icmpv6.h>
  36#include <linux/init.h>
  37#include <linux/route.h>
  38#include <linux/rtnetlink.h>
  39#include <linux/netfilter_ipv6.h>
  40#include <linux/slab.h>
 
 
  41
  42#include <asm/uaccess.h>
  43#include <linux/atomic.h>
  44
  45#include <net/icmp.h>
  46#include <net/ip.h>
 
  47#include <net/ipv6.h>
  48#include <net/ip6_route.h>
  49#include <net/addrconf.h>
  50#include <net/ip6_tunnel.h>
  51#include <net/xfrm.h>
  52#include <net/dsfield.h>
  53#include <net/inet_ecn.h>
  54#include <net/net_namespace.h>
  55#include <net/netns/generic.h>
 
 
  56
  57MODULE_AUTHOR("Ville Nuorvala");
  58MODULE_DESCRIPTION("IPv6 tunneling device");
  59MODULE_LICENSE("GPL");
 
  60MODULE_ALIAS_NETDEV("ip6tnl0");
  61
  62#ifdef IP6_TNL_DEBUG
  63#define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __func__)
  64#else
  65#define IP6_TNL_TRACE(x...) do {;} while(0)
  66#endif
  67
  68#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
  69#define IPV6_TCLASS_SHIFT 20
  70
  71#define HASH_SIZE  32
  72
  73#define HASH(addr) ((__force u32)((addr)->s6_addr32[0] ^ (addr)->s6_addr32[1] ^ \
  74		     (addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \
  75		    (HASH_SIZE - 1))
  76
  77static int ip6_tnl_dev_init(struct net_device *dev);
  78static void ip6_tnl_dev_setup(struct net_device *dev);
 
  79
  80static int ip6_tnl_net_id __read_mostly;
  81struct ip6_tnl_net {
  82	/* the IPv6 tunnel fallback device */
  83	struct net_device *fb_tnl_dev;
  84	/* lists for storing tunnels in use */
  85	struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
  86	struct ip6_tnl __rcu *tnls_wc[1];
  87	struct ip6_tnl __rcu **tnls[2];
 
  88};
  89
  90/* often modified stats are per cpu, other are shared (netdev->stats) */
  91struct pcpu_tstats {
  92	unsigned long	rx_packets;
  93	unsigned long	rx_bytes;
  94	unsigned long	tx_packets;
  95	unsigned long	tx_bytes;
  96};
  97
  98static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  99{
 100	struct pcpu_tstats sum = { 0 };
 101	int i;
 102
 103	for_each_possible_cpu(i) {
 104		const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
 105
 106		sum.rx_packets += tstats->rx_packets;
 107		sum.rx_bytes   += tstats->rx_bytes;
 108		sum.tx_packets += tstats->tx_packets;
 109		sum.tx_bytes   += tstats->tx_bytes;
 110	}
 111	dev->stats.rx_packets = sum.rx_packets;
 112	dev->stats.rx_bytes   = sum.rx_bytes;
 113	dev->stats.tx_packets = sum.tx_packets;
 114	dev->stats.tx_bytes   = sum.tx_bytes;
 115	return &dev->stats;
 116}
 117
 118/*
 119 * Locking : hash tables are protected by RCU and RTNL
 120 */
 121
 122static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
 123{
 124	struct dst_entry *dst = t->dst_cache;
 125
 126	if (dst && dst->obsolete &&
 127	    dst->ops->check(dst, t->dst_cookie) == NULL) {
 128		t->dst_cache = NULL;
 129		dst_release(dst);
 130		return NULL;
 131	}
 132
 133	return dst;
 134}
 135
 136static inline void ip6_tnl_dst_reset(struct ip6_tnl *t)
 137{
 138	dst_release(t->dst_cache);
 139	t->dst_cache = NULL;
 140}
 141
 142static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
 143{
 144	struct rt6_info *rt = (struct rt6_info *) dst;
 145	t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
 146	dst_release(t->dst_cache);
 147	t->dst_cache = dst;
 148}
 149
 150/**
 151 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 
 
 152 *   @remote: the address of the tunnel exit-point
 153 *   @local: the address of the tunnel entry-point
 154 *
 155 * Return:
 156 *   tunnel matching given end-points if found,
 157 *   else fallback tunnel if its device is up,
 158 *   else %NULL
 159 **/
 160
 161#define for_each_ip6_tunnel_rcu(start) \
 162	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 163
 164static struct ip6_tnl *
 165ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
 
 166{
 167	unsigned int h0 = HASH(remote);
 168	unsigned int h1 = HASH(local);
 169	struct ip6_tnl *t;
 170	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 
 171
 172	for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[h0 ^ h1]) {
 173		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 174		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 175		    (t->dev->flags & IFF_UP))
 
 
 
 176			return t;
 
 
 177	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 178	t = rcu_dereference(ip6n->tnls_wc[0]);
 179	if (t && (t->dev->flags & IFF_UP))
 180		return t;
 181
 182	return NULL;
 183}
 184
 185/**
 186 * ip6_tnl_bucket - get head of list matching given tunnel parameters
 
 187 *   @p: parameters containing tunnel end-points
 188 *
 189 * Description:
 190 *   ip6_tnl_bucket() returns the head of the list matching the
 191 *   &struct in6_addr entries laddr and raddr in @p.
 192 *
 193 * Return: head of IPv6 tunnel list
 194 **/
 195
 196static struct ip6_tnl __rcu **
 197ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct ip6_tnl_parm *p)
 198{
 199	const struct in6_addr *remote = &p->raddr;
 200	const struct in6_addr *local = &p->laddr;
 201	unsigned h = 0;
 202	int prio = 0;
 203
 204	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 205		prio = 1;
 206		h = HASH(remote) ^ HASH(local);
 207	}
 208	return &ip6n->tnls[prio][h];
 209}
 210
 211/**
 212 * ip6_tnl_link - add tunnel to hash table
 
 213 *   @t: tunnel to be added
 214 **/
 215
 216static void
 217ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 218{
 219	struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 220
 
 
 221	rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 222	rcu_assign_pointer(*tp, t);
 223}
 224
 225/**
 226 * ip6_tnl_unlink - remove tunnel from hash table
 
 227 *   @t: tunnel to be removed
 228 **/
 229
 230static void
 231ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 232{
 233	struct ip6_tnl __rcu **tp;
 234	struct ip6_tnl *iter;
 235
 
 
 
 236	for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 237	     (iter = rtnl_dereference(*tp)) != NULL;
 238	     tp = &iter->next) {
 239		if (t == iter) {
 240			rcu_assign_pointer(*tp, t->next);
 241			break;
 242		}
 243	}
 244}
 245
 246static void ip6_dev_free(struct net_device *dev)
 247{
 248	free_percpu(dev->tstats);
 249	free_netdev(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 250}
 251
 252/**
 253 * ip6_tnl_create() - create a new tunnel
 
 254 *   @p: tunnel parameters
 255 *   @pt: pointer to new tunnel
 256 *
 257 * Description:
 258 *   Create tunnel matching given parameters.
 259 *
 260 * Return:
 261 *   created tunnel or NULL
 262 **/
 263
 264static struct ip6_tnl *ip6_tnl_create(struct net *net, struct ip6_tnl_parm *p)
 265{
 266	struct net_device *dev;
 267	struct ip6_tnl *t;
 268	char name[IFNAMSIZ];
 269	int err;
 270	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 271
 272	if (p->name[0])
 273		strlcpy(name, p->name, IFNAMSIZ);
 274	else
 
 
 275		sprintf(name, "ip6tnl%%d");
 276
 277	dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup);
 278	if (dev == NULL)
 
 
 279		goto failed;
 280
 281	dev_net_set(dev, net);
 282
 283	t = netdev_priv(dev);
 284	t->parms = *p;
 285	err = ip6_tnl_dev_init(dev);
 
 286	if (err < 0)
 287		goto failed_free;
 288
 289	if ((err = register_netdevice(dev)) < 0)
 290		goto failed_free;
 291
 292	dev_hold(dev);
 293	ip6_tnl_link(ip6n, t);
 294	return t;
 295
 296failed_free:
 297	ip6_dev_free(dev);
 298failed:
 299	return NULL;
 300}
 301
 302/**
 303 * ip6_tnl_locate - find or create tunnel matching given parameters
 
 304 *   @p: tunnel parameters
 305 *   @create: != 0 if allowed to create new tunnel if no match found
 306 *
 307 * Description:
 308 *   ip6_tnl_locate() first tries to locate an existing tunnel
 309 *   based on @parms. If this is unsuccessful, but @create is set a new
 310 *   tunnel device is created and registered for use.
 311 *
 312 * Return:
 313 *   matching tunnel or NULL
 314 **/
 315
 316static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 317		struct ip6_tnl_parm *p, int create)
 318{
 319	const struct in6_addr *remote = &p->raddr;
 320	const struct in6_addr *local = &p->laddr;
 321	struct ip6_tnl __rcu **tp;
 322	struct ip6_tnl *t;
 323	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 324
 325	for (tp = ip6_tnl_bucket(ip6n, p);
 326	     (t = rtnl_dereference(*tp)) != NULL;
 327	     tp = &t->next) {
 328		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 329		    ipv6_addr_equal(remote, &t->parms.raddr))
 
 
 
 
 330			return t;
 
 331	}
 332	if (!create)
 333		return NULL;
 334	return ip6_tnl_create(net, p);
 335}
 336
 337/**
 338 * ip6_tnl_dev_uninit - tunnel device uninitializer
 339 *   @dev: the device to be destroyed
 340 *
 341 * Description:
 342 *   ip6_tnl_dev_uninit() removes tunnel from its list
 343 **/
 344
 345static void
 346ip6_tnl_dev_uninit(struct net_device *dev)
 347{
 348	struct ip6_tnl *t = netdev_priv(dev);
 349	struct net *net = dev_net(dev);
 350	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 351
 352	if (dev == ip6n->fb_tnl_dev)
 353		rcu_assign_pointer(ip6n->tnls_wc[0], NULL);
 354	else
 355		ip6_tnl_unlink(ip6n, t);
 356	ip6_tnl_dst_reset(t);
 357	dev_put(dev);
 358}
 359
 360/**
 361 * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 362 *   @skb: received socket buffer
 
 363 *
 364 * Return:
 365 *   0 if none was found,
 366 *   else index to encapsulation limit
 367 **/
 368
 369static __u16
 370parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
 371{
 372	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
 373	__u8 nexthdr = ipv6h->nexthdr;
 374	__u16 off = sizeof (*ipv6h);
 
 375
 376	while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 377		__u16 optlen = 0;
 378		struct ipv6_opt_hdr *hdr;
 379		if (raw + off + sizeof (*hdr) > skb->data &&
 380		    !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
 
 381			break;
 382
 383		hdr = (struct ipv6_opt_hdr *) (raw + off);
 384		if (nexthdr == NEXTHDR_FRAGMENT) {
 385			struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 386			if (frag_hdr->frag_off)
 387				break;
 388			optlen = 8;
 389		} else if (nexthdr == NEXTHDR_AUTH) {
 390			optlen = (hdr->hdrlen + 2) << 2;
 391		} else {
 392			optlen = ipv6_optlen(hdr);
 393		}
 
 
 
 
 
 
 
 
 
 
 
 394		if (nexthdr == NEXTHDR_DEST) {
 395			__u16 i = off + 2;
 
 396			while (1) {
 397				struct ipv6_tlv_tnl_enc_lim *tel;
 398
 399				/* No more room for encapsulation limit */
 400				if (i + sizeof (*tel) > off + optlen)
 401					break;
 402
 403				tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
 404				/* return index of option if found and valid */
 405				if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 406				    tel->length == 1)
 407					return i;
 408				/* else jump to next option */
 409				if (tel->type)
 410					i += tel->length + 2;
 411				else
 412					i++;
 413			}
 414		}
 415		nexthdr = hdr->nexthdr;
 416		off += optlen;
 417	}
 418	return 0;
 419}
 
 420
 421/**
 422 * ip6_tnl_err - tunnel error handler
 423 *
 424 * Description:
 425 *   ip6_tnl_err() should handle errors in the tunnel according
 426 *   to the specifications in RFC 2473.
 427 **/
 428
 429static int
 430ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 431	    u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 432{
 433	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
 434	struct ip6_tnl *t;
 435	int rel_msg = 0;
 436	u8 rel_type = ICMPV6_DEST_UNREACH;
 437	u8 rel_code = ICMPV6_ADDR_UNREACH;
 438	__u32 rel_info = 0;
 439	__u16 len;
 440	int err = -ENOENT;
 
 
 
 441
 442	/* If the packet doesn't contain the original IPv6 header we are
 443	   in trouble since we might need the source address for further
 444	   processing of the error. */
 445
 446	rcu_read_lock();
 447	if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr,
 448					&ipv6h->saddr)) == NULL)
 449		goto out;
 450
 451	if (t->parms.proto != ipproto && t->parms.proto != 0)
 
 452		goto out;
 453
 454	err = 0;
 455
 456	switch (*type) {
 457		__u32 teli;
 458		struct ipv6_tlv_tnl_enc_lim *tel;
 459		__u32 mtu;
 460	case ICMPV6_DEST_UNREACH:
 461		if (net_ratelimit())
 462			printk(KERN_WARNING
 463			       "%s: Path to destination invalid "
 464			       "or inactive!\n", t->parms.name);
 465		rel_msg = 1;
 466		break;
 467	case ICMPV6_TIME_EXCEED:
 468		if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 469			if (net_ratelimit())
 470				printk(KERN_WARNING
 471				       "%s: Too small hop limit or "
 472				       "routing loop in tunnel!\n",
 473				       t->parms.name);
 474			rel_msg = 1;
 475		}
 476		break;
 477	case ICMPV6_PARAMPROB:
 
 
 
 478		teli = 0;
 479		if ((*code) == ICMPV6_HDR_FIELD)
 480			teli = parse_tlv_tnl_enc_lim(skb, skb->data);
 481
 482		if (teli && teli == *info - 2) {
 483			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 484			if (tel->encap_limit == 0) {
 485				if (net_ratelimit())
 486					printk(KERN_WARNING
 487					       "%s: Too small encapsulation "
 488					       "limit or routing loop in "
 489					       "tunnel!\n", t->parms.name);
 490				rel_msg = 1;
 491			}
 492		} else if (net_ratelimit()) {
 493			printk(KERN_WARNING
 494			       "%s: Recipient unable to parse tunneled "
 495			       "packet!\n ", t->parms.name);
 496		}
 497		break;
 498	case ICMPV6_PKT_TOOBIG:
 
 
 
 
 
 499		mtu = *info - offset;
 500		if (mtu < IPV6_MIN_MTU)
 501			mtu = IPV6_MIN_MTU;
 502		t->dev->mtu = mtu;
 503
 504		if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
 505			rel_type = ICMPV6_PKT_TOOBIG;
 506			rel_code = 0;
 507			rel_info = mtu;
 508			rel_msg = 1;
 509		}
 510		break;
 511	}
 
 
 
 
 
 512
 513	*type = rel_type;
 514	*code = rel_code;
 515	*info = rel_info;
 516	*msg = rel_msg;
 517
 518out:
 519	rcu_read_unlock();
 520	return err;
 521}
 522
 523static int
 524ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 525	   u8 type, u8 code, int offset, __be32 info)
 526{
 527	int rel_msg = 0;
 528	u8 rel_type = type;
 529	u8 rel_code = code;
 530	__u32 rel_info = ntohl(info);
 531	int err;
 532	struct sk_buff *skb2;
 533	const struct iphdr *eiph;
 
 
 
 
 534	struct rtable *rt;
 535	struct flowi4 fl4;
 536
 537	err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 538			  &rel_msg, &rel_info, offset);
 539	if (err < 0)
 540		return err;
 541
 542	if (rel_msg == 0)
 543		return 0;
 544
 545	switch (rel_type) {
 546	case ICMPV6_DEST_UNREACH:
 547		if (rel_code != ICMPV6_ADDR_UNREACH)
 548			return 0;
 549		rel_type = ICMP_DEST_UNREACH;
 550		rel_code = ICMP_HOST_UNREACH;
 551		break;
 552	case ICMPV6_PKT_TOOBIG:
 553		if (rel_code != 0)
 554			return 0;
 555		rel_type = ICMP_DEST_UNREACH;
 556		rel_code = ICMP_FRAG_NEEDED;
 557		break;
 558	default:
 559		return 0;
 560	}
 561
 562	if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 563		return 0;
 564
 565	skb2 = skb_clone(skb, GFP_ATOMIC);
 566	if (!skb2)
 567		return 0;
 568
 569	skb_dst_drop(skb2);
 570
 571	skb_pull(skb2, offset);
 572	skb_reset_network_header(skb2);
 573	eiph = ip_hdr(skb2);
 574
 575	/* Try to guess incoming interface */
 576	rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 577				   eiph->saddr, 0,
 578				   0, 0,
 579				   IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 580	if (IS_ERR(rt))
 581		goto out;
 582
 583	skb2->dev = rt->dst.dev;
 
 584
 585	/* route "incoming" packet */
 586	if (rt->rt_flags & RTCF_LOCAL) {
 587		ip_rt_put(rt);
 588		rt = NULL;
 589		rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 590					   eiph->daddr, eiph->saddr,
 591					   0, 0,
 592					   IPPROTO_IPIP,
 593					   RT_TOS(eiph->tos), 0);
 594		if (IS_ERR(rt) ||
 595		    rt->dst.dev->type != ARPHRD_TUNNEL) {
 596			if (!IS_ERR(rt))
 597				ip_rt_put(rt);
 598			goto out;
 599		}
 600		skb_dst_set(skb2, &rt->dst);
 601	} else {
 602		ip_rt_put(rt);
 603		if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 604				   skb2->dev) ||
 605		    skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
 606			goto out;
 607	}
 608
 609	/* change mtu on this route */
 610	if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 611		if (rel_info > dst_mtu(skb_dst(skb2)))
 612			goto out;
 613
 614		skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), rel_info);
 615	}
 616
 617	icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 618
 619out:
 620	kfree_skb(skb2);
 621	return 0;
 622}
 623
 624static int
 625ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 626	   u8 type, u8 code, int offset, __be32 info)
 627{
 628	int rel_msg = 0;
 
 629	u8 rel_type = type;
 630	u8 rel_code = code;
 631	__u32 rel_info = ntohl(info);
 632	int err;
 633
 634	err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 635			  &rel_msg, &rel_info, offset);
 636	if (err < 0)
 637		return err;
 638
 639	if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 640		struct rt6_info *rt;
 641		struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 642
 643		if (!skb2)
 644			return 0;
 645
 646		skb_dst_drop(skb2);
 647		skb_pull(skb2, offset);
 648		skb_reset_network_header(skb2);
 649
 650		/* Try to guess incoming interface */
 651		rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 652				NULL, 0, 0);
 653
 654		if (rt && rt->rt6i_dev)
 655			skb2->dev = rt->rt6i_dev;
 656
 657		icmpv6_send(skb2, rel_type, rel_code, rel_info);
 658
 659		if (rt)
 660			dst_release(&rt->dst);
 661
 662		kfree_skb(skb2);
 663	}
 664
 665	return 0;
 666}
 667
 668static void ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 669					const struct ipv6hdr *ipv6h,
 670					struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 671{
 672	__u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 673
 674	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 675		ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 676
 677	if (INET_ECN_is_ce(dsfield))
 678		IP_ECN_set_ce(ip_hdr(skb));
 679}
 680
 681static void ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 682					const struct ipv6hdr *ipv6h,
 683					struct sk_buff *skb)
 684{
 685	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 686		ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 687
 688	if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h)))
 689		IP6_ECN_set_ce(ipv6_hdr(skb));
 690}
 691
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 692/* called with rcu_read_lock() */
 693static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t)
 
 
 694{
 695	struct ip6_tnl_parm *p = &t->parms;
 696	int ret = 0;
 697	struct net *net = dev_net(t->dev);
 698
 699	if (p->flags & IP6_TNL_F_CAP_RCV) {
 
 
 700		struct net_device *ldev = NULL;
 701
 702		if (p->link)
 703			ldev = dev_get_by_index_rcu(net, p->link);
 704
 705		if ((ipv6_addr_is_multicast(&p->laddr) ||
 706		     likely(ipv6_chk_addr(net, &p->laddr, ldev, 0))) &&
 707		    likely(!ipv6_chk_addr(net, &p->raddr, NULL, 0)))
 
 
 
 708			ret = 1;
 709
 710	}
 711	return ret;
 712}
 
 713
 714/**
 715 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
 716 *   @skb: received socket buffer
 717 *   @protocol: ethernet protocol ID
 718 *   @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
 719 *
 720 * Return: 0
 721 **/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 722
 723static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
 724		       __u8 ipproto,
 725		       void (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 726						    const struct ipv6hdr *ipv6h,
 727						    struct sk_buff *skb))
 728{
 729	struct ip6_tnl *t;
 730	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 731
 732	rcu_read_lock();
 
 
 
 
 
 
 733
 734	if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
 735					&ipv6h->daddr)) != NULL) {
 736		struct pcpu_tstats *tstats;
 
 
 
 737
 738		if (t->parms.proto != ipproto && t->parms.proto != 0) {
 739			rcu_read_unlock();
 740			goto discard;
 741		}
 
 742
 743		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 744			rcu_read_unlock();
 745			goto discard;
 746		}
 747
 748		if (!ip6_tnl_rcv_ctl(t)) {
 749			t->dev->stats.rx_dropped++;
 750			rcu_read_unlock();
 751			goto discard;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 752		}
 753		secpath_reset(skb);
 754		skb->mac_header = skb->network_header;
 755		skb_reset_network_header(skb);
 756		skb->protocol = htons(protocol);
 757		skb->pkt_type = PACKET_HOST;
 758		memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 759
 760		tstats = this_cpu_ptr(t->dev->tstats);
 761		tstats->rx_packets++;
 762		tstats->rx_bytes += skb->len;
 763
 764		__skb_tunnel_rx(skb, t->dev);
 765
 766		dscp_ecn_decapsulate(t, ipv6h, skb);
 
 767
 768		netif_rx(skb);
 
 769
 770		rcu_read_unlock();
 771		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 772	}
 
 773	rcu_read_unlock();
 774	return 1;
 775
 776discard:
 
 
 
 777	kfree_skb(skb);
 778	return 0;
 779}
 780
 781static int ip4ip6_rcv(struct sk_buff *skb)
 782{
 783	return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
 784			   ip4ip6_dscp_ecn_decapsulate);
 785}
 786
 787static int ip6ip6_rcv(struct sk_buff *skb)
 788{
 789	return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
 790			   ip6ip6_dscp_ecn_decapsulate);
 
 
 
 
 
 
 791}
 792
 793struct ipv6_tel_txoption {
 794	struct ipv6_txoptions ops;
 795	__u8 dst_opt[8];
 796};
 797
 798static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 799{
 800	memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 801
 802	opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 803	opt->dst_opt[3] = 1;
 804	opt->dst_opt[4] = encap_limit;
 805	opt->dst_opt[5] = IPV6_TLV_PADN;
 806	opt->dst_opt[6] = 1;
 807
 808	opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 809	opt->ops.opt_nflen = 8;
 810}
 811
 812/**
 813 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 814 *   @t: the outgoing tunnel device
 815 *   @hdr: IPv6 header from the incoming packet
 816 *
 817 * Description:
 818 *   Avoid trivial tunneling loop by checking that tunnel exit-point
 819 *   doesn't match source of incoming packet.
 820 *
 821 * Return:
 822 *   1 if conflict,
 823 *   0 else
 824 **/
 825
 826static inline int
 827ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 828{
 829	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 830}
 831
 832static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
 
 
 833{
 834	struct ip6_tnl_parm *p = &t->parms;
 835	int ret = 0;
 836	struct net *net = dev_net(t->dev);
 837
 838	if (p->flags & IP6_TNL_F_CAP_XMIT) {
 
 
 
 
 
 839		struct net_device *ldev = NULL;
 840
 841		rcu_read_lock();
 842		if (p->link)
 843			ldev = dev_get_by_index_rcu(net, p->link);
 844
 845		if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0)))
 846			printk(KERN_WARNING
 847			       "%s xmit: Local address not yet configured!\n",
 848			       p->name);
 849		else if (!ipv6_addr_is_multicast(&p->raddr) &&
 850			 unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0)))
 851			printk(KERN_WARNING
 852			       "%s xmit: Routing loop! "
 853			       "Remote address found on this node!\n",
 854			       p->name);
 855		else
 856			ret = 1;
 857		rcu_read_unlock();
 858	}
 859	return ret;
 860}
 
 
 861/**
 862 * ip6_tnl_xmit2 - encapsulate packet and send
 863 *   @skb: the outgoing socket buffer
 864 *   @dev: the outgoing tunnel device
 865 *   @dsfield: dscp code for outer header
 866 *   @fl: flow of tunneled packet
 867 *   @encap_limit: encapsulation limit
 868 *   @pmtu: Path MTU is stored if packet is too big
 
 869 *
 870 * Description:
 871 *   Build new header and do some sanity checks on the packet before sending
 872 *   it.
 873 *
 874 * Return:
 875 *   0 on success
 876 *   -1 fail
 877 *   %-EMSGSIZE message too big. return mtu in this case.
 878 **/
 879
 880static int ip6_tnl_xmit2(struct sk_buff *skb,
 881			 struct net_device *dev,
 882			 __u8 dsfield,
 883			 struct flowi6 *fl6,
 884			 int encap_limit,
 885			 __u32 *pmtu)
 886{
 887	struct net *net = dev_net(dev);
 888	struct ip6_tnl *t = netdev_priv(dev);
 889	struct net_device_stats *stats = &t->dev->stats;
 890	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 891	struct ipv6_tel_txoption opt;
 892	struct dst_entry *dst;
 893	struct net_device *tdev;
 894	int mtu;
 895	unsigned int max_headroom = sizeof(struct ipv6hdr);
 896	u8 proto;
 
 
 
 
 897	int err = -1;
 898	int pkt_len;
 899
 900	if ((dst = ip6_tnl_dst_check(t)) != NULL)
 901		dst_hold(dst);
 902	else {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 903		dst = ip6_route_output(net, NULL, fl6);
 904
 905		if (dst->error)
 906			goto tx_err_link_failure;
 907		dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
 908		if (IS_ERR(dst)) {
 909			err = PTR_ERR(dst);
 910			dst = NULL;
 911			goto tx_err_link_failure;
 912		}
 
 
 
 
 
 913	}
 914
 915	tdev = dst->dev;
 916
 917	if (tdev == dev) {
 918		stats->collisions++;
 919		if (net_ratelimit())
 920			printk(KERN_WARNING
 921			       "%s: Local routing loop detected!\n",
 922			       t->parms.name);
 923		goto tx_err_dst_release;
 924	}
 925	mtu = dst_mtu(dst) - sizeof (*ipv6h);
 926	if (encap_limit >= 0) {
 927		max_headroom += 8;
 928		mtu -= 8;
 929	}
 930	if (mtu < IPV6_MIN_MTU)
 931		mtu = IPV6_MIN_MTU;
 932	if (skb_dst(skb))
 933		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
 934	if (skb->len > mtu) {
 935		*pmtu = mtu;
 936		err = -EMSGSIZE;
 937		goto tx_err_dst_release;
 938	}
 939
 
 
 
 
 
 
 
 
 
 
 
 
 
 940	/*
 941	 * Okay, now see if we can stuff it in the buffer as-is.
 942	 */
 943	max_headroom += LL_RESERVED_SPACE(tdev);
 944
 945	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
 946	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
 947		struct sk_buff *new_skb;
 948
 949		if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
 
 950			goto tx_err_dst_release;
 951
 952		if (skb->sk)
 953			skb_set_owner_w(new_skb, skb->sk);
 954		kfree_skb(skb);
 955		skb = new_skb;
 956	}
 957	skb_dst_drop(skb);
 958	skb_dst_set(skb, dst_clone(dst));
 959
 960	skb->transport_header = skb->network_header;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 961
 962	proto = fl6->flowi6_proto;
 963	if (encap_limit >= 0) {
 964		init_tel_txopt(&opt, encap_limit);
 965		ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
 966	}
 
 967	skb_push(skb, sizeof(struct ipv6hdr));
 968	skb_reset_network_header(skb);
 969	ipv6h = ipv6_hdr(skb);
 970	*(__be32*)ipv6h = fl6->flowlabel | htonl(0x60000000);
 971	dsfield = INET_ECN_encapsulate(0, dsfield);
 972	ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
 973	ipv6h->hop_limit = t->parms.hop_limit;
 974	ipv6h->nexthdr = proto;
 975	ipv6_addr_copy(&ipv6h->saddr, &fl6->saddr);
 976	ipv6_addr_copy(&ipv6h->daddr, &fl6->daddr);
 977	nf_reset(skb);
 978	pkt_len = skb->len;
 979	err = ip6_local_out(skb);
 980
 981	if (net_xmit_eval(err) == 0) {
 982		struct pcpu_tstats *tstats = this_cpu_ptr(t->dev->tstats);
 983
 984		tstats->tx_bytes += pkt_len;
 985		tstats->tx_packets++;
 986	} else {
 987		stats->tx_errors++;
 988		stats->tx_aborted_errors++;
 989	}
 990	ip6_tnl_dst_store(t, dst);
 991	return 0;
 992tx_err_link_failure:
 993	stats->tx_carrier_errors++;
 994	dst_link_failure(skb);
 995tx_err_dst_release:
 996	dst_release(dst);
 997	return err;
 998}
 
 999
1000static inline int
1001ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
 
1002{
1003	struct ip6_tnl *t = netdev_priv(dev);
1004	const struct iphdr  *iph = ip_hdr(skb);
 
1005	int encap_limit = -1;
 
1006	struct flowi6 fl6;
1007	__u8 dsfield;
1008	__u32 mtu;
 
1009	int err;
1010
1011	if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
1012	    !ip6_tnl_xmit_ctl(t))
1013		return -1;
1014
1015	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1016		encap_limit = t->parms.encap_limit;
1017
1018	memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1019	fl6.flowi6_proto = IPPROTO_IPIP;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1020
1021	dsfield = ipv4_get_dsfield(iph);
 
 
 
 
 
 
 
 
1022
1023	if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS))
1024		fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1025					  & IPV6_TCLASS_MASK;
1026
1027	err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1028	if (err != 0) {
1029		/* XXX: send ICMP error even if DF is not set. */
1030		if (err == -EMSGSIZE)
1031			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1032				  htonl(mtu));
1033		return -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1034	}
1035
1036	return 0;
1037}
1038
1039static inline int
1040ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1041{
1042	struct ip6_tnl *t = netdev_priv(dev);
1043	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1044	int encap_limit = -1;
1045	__u16 offset;
1046	struct flowi6 fl6;
1047	__u8 dsfield;
1048	__u32 mtu;
1049	int err;
1050
1051	if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
1052	    !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
1053		return -1;
1054
1055	offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb));
1056	if (offset > 0) {
1057		struct ipv6_tlv_tnl_enc_lim *tel;
1058		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1059		if (tel->encap_limit == 0) {
1060			icmpv6_send(skb, ICMPV6_PARAMPROB,
1061				    ICMPV6_HDR_FIELD, offset + 2);
1062			return -1;
1063		}
1064		encap_limit = tel->encap_limit - 1;
1065	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1066		encap_limit = t->parms.encap_limit;
1067
1068	memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1069	fl6.flowi6_proto = IPPROTO_IPV6;
1070
1071	dsfield = ipv6_get_dsfield(ipv6h);
1072	if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS))
1073		fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1074	if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL))
1075		fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
1076
1077	err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
 
1078	if (err != 0) {
 
1079		if (err == -EMSGSIZE)
1080			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 
 
 
 
 
 
 
 
 
 
1081		return -1;
1082	}
1083
1084	return 0;
1085}
1086
1087static netdev_tx_t
1088ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1089{
1090	struct ip6_tnl *t = netdev_priv(dev);
1091	struct net_device_stats *stats = &t->dev->stats;
1092	int ret;
1093
 
 
 
1094	switch (skb->protocol) {
1095	case htons(ETH_P_IP):
1096		ret = ip4ip6_tnl_xmit(skb, dev);
1097		break;
1098	case htons(ETH_P_IPV6):
1099		ret = ip6ip6_tnl_xmit(skb, dev);
 
 
 
 
 
1100		break;
1101	default:
1102		goto tx_err;
1103	}
1104
 
1105	if (ret < 0)
1106		goto tx_err;
1107
1108	return NETDEV_TX_OK;
1109
1110tx_err:
1111	stats->tx_errors++;
1112	stats->tx_dropped++;
1113	kfree_skb(skb);
1114	return NETDEV_TX_OK;
1115}
1116
1117static void ip6_tnl_set_cap(struct ip6_tnl *t)
1118{
1119	struct ip6_tnl_parm *p = &t->parms;
1120	int ltype = ipv6_addr_type(&p->laddr);
1121	int rtype = ipv6_addr_type(&p->raddr);
1122
1123	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV);
1124
1125	if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
1126	    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
1127	    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
1128	    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
1129		if (ltype&IPV6_ADDR_UNICAST)
1130			p->flags |= IP6_TNL_F_CAP_XMIT;
1131		if (rtype&IPV6_ADDR_UNICAST)
1132			p->flags |= IP6_TNL_F_CAP_RCV;
1133	}
1134}
1135
1136static void ip6_tnl_link_config(struct ip6_tnl *t)
1137{
1138	struct net_device *dev = t->dev;
1139	struct ip6_tnl_parm *p = &t->parms;
 
1140	struct flowi6 *fl6 = &t->fl.u.ip6;
 
 
1141
1142	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1143	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1144
1145	/* Set up flowi template */
1146	ipv6_addr_copy(&fl6->saddr, &p->laddr);
1147	ipv6_addr_copy(&fl6->daddr, &p->raddr);
1148	fl6->flowi6_oif = p->link;
1149	fl6->flowlabel = 0;
1150
1151	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1152		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1153	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1154		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1155
1156	ip6_tnl_set_cap(t);
 
1157
1158	if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1159		dev->flags |= IFF_POINTOPOINT;
1160	else
1161		dev->flags &= ~IFF_POINTOPOINT;
1162
1163	dev->iflink = p->link;
 
 
1164
1165	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1166		int strict = (ipv6_addr_type(&p->raddr) &
1167			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1168
1169		struct rt6_info *rt = rt6_lookup(dev_net(dev),
1170						 &p->raddr, &p->laddr,
1171						 p->link, strict);
 
 
 
 
1172
1173		if (rt == NULL)
1174			return;
1175
1176		if (rt->rt6i_dev) {
1177			dev->hard_header_len = rt->rt6i_dev->hard_header_len +
1178				sizeof (struct ipv6hdr);
 
1179
1180			dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr);
1181			if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1182				dev->mtu-=8;
1183
1184			if (dev->mtu < IPV6_MIN_MTU)
1185				dev->mtu = IPV6_MIN_MTU;
 
1186		}
1187		dst_release(&rt->dst);
1188	}
1189}
1190
1191/**
1192 * ip6_tnl_change - update the tunnel parameters
1193 *   @t: tunnel to be changed
1194 *   @p: tunnel configuration parameters
1195 *
1196 * Description:
1197 *   ip6_tnl_change() updates the tunnel parameters
1198 **/
1199
1200static int
1201ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p)
1202{
1203	ipv6_addr_copy(&t->parms.laddr, &p->laddr);
1204	ipv6_addr_copy(&t->parms.raddr, &p->raddr);
1205	t->parms.flags = p->flags;
1206	t->parms.hop_limit = p->hop_limit;
1207	t->parms.encap_limit = p->encap_limit;
1208	t->parms.flowinfo = p->flowinfo;
1209	t->parms.link = p->link;
1210	t->parms.proto = p->proto;
1211	ip6_tnl_dst_reset(t);
 
1212	ip6_tnl_link_config(t);
1213	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1214}
1215
1216/**
1217 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1218 *   @dev: virtual device associated with tunnel
1219 *   @ifr: parameters passed from userspace
 
1220 *   @cmd: command to be performed
1221 *
1222 * Description:
1223 *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1224 *   from userspace.
1225 *
1226 *   The possible commands are the following:
1227 *     %SIOCGETTUNNEL: get tunnel parameters for device
1228 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1229 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1230 *     %SIOCDELTUNNEL: delete tunnel
1231 *
1232 *   The fallback device "ip6tnl0", created during module
1233 *   initialization, can be used for creating other tunnel devices.
1234 *
1235 * Return:
1236 *   0 on success,
1237 *   %-EFAULT if unable to copy data to or from userspace,
1238 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1239 *   %-EINVAL if passed tunnel parameters are invalid,
1240 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1241 *   %-ENODEV if attempting to change or delete a nonexisting device
1242 **/
1243
1244static int
1245ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 
1246{
1247	int err = 0;
1248	struct ip6_tnl_parm p;
1249	struct ip6_tnl *t = NULL;
1250	struct net *net = dev_net(dev);
 
1251	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1252
 
 
1253	switch (cmd) {
1254	case SIOCGETTUNNEL:
1255		if (dev == ip6n->fb_tnl_dev) {
1256			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
1257				err = -EFAULT;
1258				break;
1259			}
1260			t = ip6_tnl_locate(net, &p, 0);
 
 
 
 
 
1261		}
1262		if (t == NULL)
1263			t = netdev_priv(dev);
1264		memcpy(&p, &t->parms, sizeof (p));
1265		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
1266			err = -EFAULT;
1267		}
1268		break;
1269	case SIOCADDTUNNEL:
1270	case SIOCCHGTUNNEL:
1271		err = -EPERM;
1272		if (!capable(CAP_NET_ADMIN))
1273			break;
1274		err = -EFAULT;
1275		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1276			break;
1277		err = -EINVAL;
1278		if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1279		    p.proto != 0)
1280			break;
1281		t = ip6_tnl_locate(net, &p, cmd == SIOCADDTUNNEL);
1282		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
1283			if (t != NULL) {
 
1284				if (t->dev != dev) {
1285					err = -EEXIST;
1286					break;
1287				}
1288			} else
1289				t = netdev_priv(dev);
1290
1291			ip6_tnl_unlink(ip6n, t);
1292			synchronize_net();
1293			err = ip6_tnl_change(t, &p);
1294			ip6_tnl_link(ip6n, t);
1295			netdev_state_change(dev);
1296		}
1297		if (t) {
1298			err = 0;
1299			if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p)))
 
1300				err = -EFAULT;
1301
1302		} else
1303			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
 
1304		break;
1305	case SIOCDELTUNNEL:
1306		err = -EPERM;
1307		if (!capable(CAP_NET_ADMIN))
1308			break;
1309
1310		if (dev == ip6n->fb_tnl_dev) {
1311			err = -EFAULT;
1312			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1313				break;
1314			err = -ENOENT;
1315			if ((t = ip6_tnl_locate(net, &p, 0)) == NULL)
 
 
1316				break;
1317			err = -EPERM;
1318			if (t->dev == ip6n->fb_tnl_dev)
1319				break;
1320			dev = t->dev;
1321		}
1322		err = 0;
1323		unregister_netdevice(dev);
1324		break;
1325	default:
1326		err = -EINVAL;
1327	}
1328	return err;
1329}
1330
1331/**
1332 * ip6_tnl_change_mtu - change mtu manually for tunnel device
1333 *   @dev: virtual device associated with tunnel
1334 *   @new_mtu: the new mtu
1335 *
1336 * Return:
1337 *   0 on success,
1338 *   %-EINVAL if mtu too small
1339 **/
1340
1341static int
1342ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1343{
1344	if (new_mtu < IPV6_MIN_MTU) {
1345		return -EINVAL;
 
 
 
 
 
 
 
 
1346	}
1347	dev->mtu = new_mtu;
 
 
 
 
 
 
 
1348	return 0;
1349}
 
 
 
 
 
 
 
 
 
1350
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1351
1352static const struct net_device_ops ip6_tnl_netdev_ops = {
 
1353	.ndo_uninit	= ip6_tnl_dev_uninit,
1354	.ndo_start_xmit = ip6_tnl_xmit,
1355	.ndo_do_ioctl	= ip6_tnl_ioctl,
1356	.ndo_change_mtu = ip6_tnl_change_mtu,
1357	.ndo_get_stats	= ip6_get_stats,
 
1358};
1359
 
 
 
 
 
1360
1361/**
1362 * ip6_tnl_dev_setup - setup virtual tunnel device
1363 *   @dev: virtual device associated with tunnel
1364 *
1365 * Description:
1366 *   Initialize function pointers and device parameters
1367 **/
1368
1369static void ip6_tnl_dev_setup(struct net_device *dev)
1370{
1371	struct ip6_tnl *t;
1372
1373	dev->netdev_ops = &ip6_tnl_netdev_ops;
1374	dev->destructor = ip6_dev_free;
 
 
1375
1376	dev->type = ARPHRD_TUNNEL6;
1377	dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1378	dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1379	t = netdev_priv(dev);
1380	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1381		dev->mtu-=8;
1382	dev->flags |= IFF_NOARP;
1383	dev->addr_len = sizeof(struct in6_addr);
1384	dev->features |= NETIF_F_NETNS_LOCAL;
1385	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
 
 
 
 
 
 
 
 
1386}
1387
1388
1389/**
1390 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1391 *   @dev: virtual device associated with tunnel
1392 **/
1393
1394static inline int
1395ip6_tnl_dev_init_gen(struct net_device *dev)
1396{
1397	struct ip6_tnl *t = netdev_priv(dev);
 
 
1398
1399	t->dev = dev;
1400	strcpy(t->parms.name, dev->name);
1401	dev->tstats = alloc_percpu(struct pcpu_tstats);
1402	if (!dev->tstats)
1403		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1404	return 0;
 
 
 
 
 
1405}
1406
1407/**
1408 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1409 *   @dev: virtual device associated with tunnel
1410 **/
1411
1412static int ip6_tnl_dev_init(struct net_device *dev)
1413{
1414	struct ip6_tnl *t = netdev_priv(dev);
1415	int err = ip6_tnl_dev_init_gen(dev);
1416
1417	if (err)
1418		return err;
1419	ip6_tnl_link_config(t);
 
 
1420	return 0;
1421}
1422
1423/**
1424 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1425 *   @dev: fallback device
1426 *
1427 * Return: 0
1428 **/
1429
1430static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1431{
1432	struct ip6_tnl *t = netdev_priv(dev);
1433	struct net *net = dev_net(dev);
1434	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1435	int err = ip6_tnl_dev_init_gen(dev);
1436
1437	if (err)
1438		return err;
1439
1440	t->parms.proto = IPPROTO_IPV6;
1441	dev_hold(dev);
1442	rcu_assign_pointer(ip6n->tnls_wc[0], t);
1443	return 0;
1444}
1445
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1446static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1447	.handler	= ip4ip6_rcv,
1448	.err_handler	= ip4ip6_err,
1449	.priority	=	1,
1450};
1451
1452static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1453	.handler	= ip6ip6_rcv,
1454	.err_handler	= ip6ip6_err,
1455	.priority	=	1,
1456};
1457
1458static void __net_exit ip6_tnl_destroy_tunnels(struct ip6_tnl_net *ip6n)
 
 
 
 
 
 
1459{
 
 
1460	int h;
1461	struct ip6_tnl *t;
1462	LIST_HEAD(list);
1463
1464	for (h = 0; h < HASH_SIZE; h++) {
 
 
 
 
1465		t = rtnl_dereference(ip6n->tnls_r_l[h]);
1466		while (t != NULL) {
1467			unregister_netdevice_queue(t->dev, &list);
 
 
 
 
1468			t = rtnl_dereference(t->next);
1469		}
1470	}
1471
1472	t = rtnl_dereference(ip6n->tnls_wc[0]);
1473	unregister_netdevice_queue(t->dev, &list);
1474	unregister_netdevice_many(&list);
 
 
 
 
 
 
1475}
1476
1477static int __net_init ip6_tnl_init_net(struct net *net)
1478{
1479	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 
1480	int err;
1481
1482	ip6n->tnls[0] = ip6n->tnls_wc;
1483	ip6n->tnls[1] = ip6n->tnls_r_l;
1484
 
 
1485	err = -ENOMEM;
1486	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1487				      ip6_tnl_dev_setup);
1488
1489	if (!ip6n->fb_tnl_dev)
1490		goto err_alloc_dev;
1491	dev_net_set(ip6n->fb_tnl_dev, net);
 
 
 
 
 
1492
1493	err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1494	if (err < 0)
1495		goto err_register;
1496
1497	err = register_netdev(ip6n->fb_tnl_dev);
1498	if (err < 0)
1499		goto err_register;
 
 
 
 
1500	return 0;
1501
1502err_register:
1503	ip6_dev_free(ip6n->fb_tnl_dev);
1504err_alloc_dev:
1505	return err;
1506}
1507
1508static void __net_exit ip6_tnl_exit_net(struct net *net)
 
1509{
1510	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1511
1512	rtnl_lock();
1513	ip6_tnl_destroy_tunnels(ip6n);
1514	rtnl_unlock();
1515}
1516
1517static struct pernet_operations ip6_tnl_net_ops = {
1518	.init = ip6_tnl_init_net,
1519	.exit = ip6_tnl_exit_net,
1520	.id   = &ip6_tnl_net_id,
1521	.size = sizeof(struct ip6_tnl_net),
1522};
1523
1524/**
1525 * ip6_tunnel_init - register protocol and reserve needed resources
1526 *
1527 * Return: 0 on success
1528 **/
1529
1530static int __init ip6_tunnel_init(void)
1531{
1532	int  err;
1533
 
 
 
1534	err = register_pernet_device(&ip6_tnl_net_ops);
1535	if (err < 0)
1536		goto out_pernet;
1537
1538	err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1539	if (err < 0) {
1540		printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n");
1541		goto out_ip4ip6;
1542	}
1543
1544	err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1545	if (err < 0) {
1546		printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n");
1547		goto out_ip6ip6;
1548	}
1549
 
 
 
 
 
 
 
 
 
 
 
 
1550	return 0;
1551
 
 
 
 
 
1552out_ip6ip6:
1553	xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1554out_ip4ip6:
1555	unregister_pernet_device(&ip6_tnl_net_ops);
1556out_pernet:
1557	return err;
1558}
1559
1560/**
1561 * ip6_tunnel_cleanup - free resources and unregister protocol
1562 **/
1563
1564static void __exit ip6_tunnel_cleanup(void)
1565{
 
1566	if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1567		printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n");
1568
1569	if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1570		printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n");
1571
 
 
 
1572	unregister_pernet_device(&ip6_tnl_net_ops);
1573}
1574
1575module_init(ip6_tunnel_init);
1576module_exit(ip6_tunnel_cleanup);
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	IPv6 tunneling device
   4 *	Linux INET6 implementation
   5 *
   6 *	Authors:
   7 *	Ville Nuorvala		<vnuorval@tcs.hut.fi>
   8 *	Yasuyuki Kozakai	<kozakai@linux-ipv6.org>
   9 *
  10 *      Based on:
  11 *      linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
  12 *
  13 *      RFC 2473
 
 
 
 
 
 
  14 */
  15
  16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  17
  18#include <linux/module.h>
  19#include <linux/capability.h>
  20#include <linux/errno.h>
  21#include <linux/types.h>
  22#include <linux/sockios.h>
  23#include <linux/icmp.h>
  24#include <linux/if.h>
  25#include <linux/in.h>
  26#include <linux/ip.h>
 
  27#include <linux/net.h>
  28#include <linux/in6.h>
  29#include <linux/netdevice.h>
  30#include <linux/if_arp.h>
  31#include <linux/icmpv6.h>
  32#include <linux/init.h>
  33#include <linux/route.h>
  34#include <linux/rtnetlink.h>
  35#include <linux/netfilter_ipv6.h>
  36#include <linux/slab.h>
  37#include <linux/hash.h>
  38#include <linux/etherdevice.h>
  39
  40#include <linux/uaccess.h>
  41#include <linux/atomic.h>
  42
  43#include <net/icmp.h>
  44#include <net/ip.h>
  45#include <net/ip_tunnels.h>
  46#include <net/ipv6.h>
  47#include <net/ip6_route.h>
  48#include <net/addrconf.h>
  49#include <net/ip6_tunnel.h>
  50#include <net/xfrm.h>
  51#include <net/dsfield.h>
  52#include <net/inet_ecn.h>
  53#include <net/net_namespace.h>
  54#include <net/netns/generic.h>
  55#include <net/dst_metadata.h>
  56#include <net/inet_dscp.h>
  57
  58MODULE_AUTHOR("Ville Nuorvala");
  59MODULE_DESCRIPTION("IPv6 tunneling device");
  60MODULE_LICENSE("GPL");
  61MODULE_ALIAS_RTNL_LINK("ip6tnl");
  62MODULE_ALIAS_NETDEV("ip6tnl0");
  63
  64#define IP6_TUNNEL_HASH_SIZE_SHIFT  5
  65#define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT)
  66
  67static bool log_ecn_error = true;
  68module_param(log_ecn_error, bool, 0644);
  69MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  70
  71static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  72{
  73	u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  74
  75	return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT);
  76}
 
  77
  78static int ip6_tnl_dev_init(struct net_device *dev);
  79static void ip6_tnl_dev_setup(struct net_device *dev);
  80static struct rtnl_link_ops ip6_link_ops __read_mostly;
  81
  82static unsigned int ip6_tnl_net_id __read_mostly;
  83struct ip6_tnl_net {
  84	/* the IPv6 tunnel fallback device */
  85	struct net_device *fb_tnl_dev;
  86	/* lists for storing tunnels in use */
  87	struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE];
  88	struct ip6_tnl __rcu *tnls_wc[1];
  89	struct ip6_tnl __rcu **tnls[2];
  90	struct ip6_tnl __rcu *collect_md_tun;
  91};
  92
  93static inline int ip6_tnl_mpls_supported(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  94{
  95	return IS_ENABLED(CONFIG_MPLS);
 
 
 
 
 
 
 
 
 
  96}
  97
  98#define for_each_ip6_tunnel_rcu(start) \
  99	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 
 
 
 
 
 
 
 
 
 
 
 100
 101/**
 102 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 103 *   @net: network namespace
 104 *   @link: ifindex of underlying interface
 105 *   @remote: the address of the tunnel exit-point
 106 *   @local: the address of the tunnel entry-point
 107 *
 108 * Return:
 109 *   tunnel matching given end-points if found,
 110 *   else fallback tunnel if its device is up,
 111 *   else %NULL
 112 **/
 113
 
 
 
 114static struct ip6_tnl *
 115ip6_tnl_lookup(struct net *net, int link,
 116	       const struct in6_addr *remote, const struct in6_addr *local)
 117{
 118	unsigned int hash = HASH(remote, local);
 119	struct ip6_tnl *t, *cand = NULL;
 
 120	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 121	struct in6_addr any;
 122
 123	for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 124		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 125		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
 126		    !(t->dev->flags & IFF_UP))
 127			continue;
 128
 129		if (link == t->parms.link)
 130			return t;
 131		else
 132			cand = t;
 133	}
 134
 135	memset(&any, 0, sizeof(any));
 136	hash = HASH(&any, local);
 137	for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 138		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 139		    !ipv6_addr_any(&t->parms.raddr) ||
 140		    !(t->dev->flags & IFF_UP))
 141			continue;
 142
 143		if (link == t->parms.link)
 144			return t;
 145		else if (!cand)
 146			cand = t;
 147	}
 148
 149	hash = HASH(remote, &any);
 150	for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 151		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 152		    !ipv6_addr_any(&t->parms.laddr) ||
 153		    !(t->dev->flags & IFF_UP))
 154			continue;
 155
 156		if (link == t->parms.link)
 157			return t;
 158		else if (!cand)
 159			cand = t;
 160	}
 161
 162	if (cand)
 163		return cand;
 164
 165	t = rcu_dereference(ip6n->collect_md_tun);
 166	if (t && t->dev->flags & IFF_UP)
 167		return t;
 168
 169	t = rcu_dereference(ip6n->tnls_wc[0]);
 170	if (t && (t->dev->flags & IFF_UP))
 171		return t;
 172
 173	return NULL;
 174}
 175
 176/**
 177 * ip6_tnl_bucket - get head of list matching given tunnel parameters
 178 *   @ip6n: the private data for ip6_vti in the netns
 179 *   @p: parameters containing tunnel end-points
 180 *
 181 * Description:
 182 *   ip6_tnl_bucket() returns the head of the list matching the
 183 *   &struct in6_addr entries laddr and raddr in @p.
 184 *
 185 * Return: head of IPv6 tunnel list
 186 **/
 187
 188static struct ip6_tnl __rcu **
 189ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 190{
 191	const struct in6_addr *remote = &p->raddr;
 192	const struct in6_addr *local = &p->laddr;
 193	unsigned int h = 0;
 194	int prio = 0;
 195
 196	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 197		prio = 1;
 198		h = HASH(remote, local);
 199	}
 200	return &ip6n->tnls[prio][h];
 201}
 202
 203/**
 204 * ip6_tnl_link - add tunnel to hash table
 205 *   @ip6n: the private data for ip6_vti in the netns
 206 *   @t: tunnel to be added
 207 **/
 208
 209static void
 210ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 211{
 212	struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 213
 214	if (t->parms.collect_md)
 215		rcu_assign_pointer(ip6n->collect_md_tun, t);
 216	rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 217	rcu_assign_pointer(*tp, t);
 218}
 219
 220/**
 221 * ip6_tnl_unlink - remove tunnel from hash table
 222 *   @ip6n: the private data for ip6_vti in the netns
 223 *   @t: tunnel to be removed
 224 **/
 225
 226static void
 227ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 228{
 229	struct ip6_tnl __rcu **tp;
 230	struct ip6_tnl *iter;
 231
 232	if (t->parms.collect_md)
 233		rcu_assign_pointer(ip6n->collect_md_tun, NULL);
 234
 235	for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 236	     (iter = rtnl_dereference(*tp)) != NULL;
 237	     tp = &iter->next) {
 238		if (t == iter) {
 239			rcu_assign_pointer(*tp, t->next);
 240			break;
 241		}
 242	}
 243}
 244
 245static void ip6_dev_free(struct net_device *dev)
 246{
 247	struct ip6_tnl *t = netdev_priv(dev);
 248
 249	gro_cells_destroy(&t->gro_cells);
 250	dst_cache_destroy(&t->dst_cache);
 251}
 252
 253static int ip6_tnl_create2(struct net_device *dev)
 254{
 255	struct ip6_tnl *t = netdev_priv(dev);
 256	struct net *net = dev_net(dev);
 257	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 258	int err;
 259
 260	dev->rtnl_link_ops = &ip6_link_ops;
 261	err = register_netdevice(dev);
 262	if (err < 0)
 263		goto out;
 264
 265	strcpy(t->parms.name, dev->name);
 266
 267	ip6_tnl_link(ip6n, t);
 268	return 0;
 269
 270out:
 271	return err;
 272}
 273
 274/**
 275 * ip6_tnl_create - create a new tunnel
 276 *   @net: network namespace
 277 *   @p: tunnel parameters
 
 278 *
 279 * Description:
 280 *   Create tunnel matching given parameters.
 281 *
 282 * Return:
 283 *   created tunnel or error pointer
 284 **/
 285
 286static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 287{
 288	struct net_device *dev;
 289	struct ip6_tnl *t;
 290	char name[IFNAMSIZ];
 291	int err = -E2BIG;
 
 292
 293	if (p->name[0]) {
 294		if (!dev_valid_name(p->name))
 295			goto failed;
 296		strscpy(name, p->name, IFNAMSIZ);
 297	} else {
 298		sprintf(name, "ip6tnl%%d");
 299	}
 300	err = -ENOMEM;
 301	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 302			   ip6_tnl_dev_setup);
 303	if (!dev)
 304		goto failed;
 305
 306	dev_net_set(dev, net);
 307
 308	t = netdev_priv(dev);
 309	t->parms = *p;
 310	t->net = dev_net(dev);
 311	err = ip6_tnl_create2(dev);
 312	if (err < 0)
 313		goto failed_free;
 314
 
 
 
 
 
 315	return t;
 316
 317failed_free:
 318	free_netdev(dev);
 319failed:
 320	return ERR_PTR(err);
 321}
 322
 323/**
 324 * ip6_tnl_locate - find or create tunnel matching given parameters
 325 *   @net: network namespace
 326 *   @p: tunnel parameters
 327 *   @create: != 0 if allowed to create new tunnel if no match found
 328 *
 329 * Description:
 330 *   ip6_tnl_locate() first tries to locate an existing tunnel
 331 *   based on @parms. If this is unsuccessful, but @create is set a new
 332 *   tunnel device is created and registered for use.
 333 *
 334 * Return:
 335 *   matching tunnel or error pointer
 336 **/
 337
 338static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 339		struct __ip6_tnl_parm *p, int create)
 340{
 341	const struct in6_addr *remote = &p->raddr;
 342	const struct in6_addr *local = &p->laddr;
 343	struct ip6_tnl __rcu **tp;
 344	struct ip6_tnl *t;
 345	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 346
 347	for (tp = ip6_tnl_bucket(ip6n, p);
 348	     (t = rtnl_dereference(*tp)) != NULL;
 349	     tp = &t->next) {
 350		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 351		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 352		    p->link == t->parms.link) {
 353			if (create)
 354				return ERR_PTR(-EEXIST);
 355
 356			return t;
 357		}
 358	}
 359	if (!create)
 360		return ERR_PTR(-ENODEV);
 361	return ip6_tnl_create(net, p);
 362}
 363
 364/**
 365 * ip6_tnl_dev_uninit - tunnel device uninitializer
 366 *   @dev: the device to be destroyed
 367 *
 368 * Description:
 369 *   ip6_tnl_dev_uninit() removes tunnel from its list
 370 **/
 371
 372static void
 373ip6_tnl_dev_uninit(struct net_device *dev)
 374{
 375	struct ip6_tnl *t = netdev_priv(dev);
 376	struct net *net = t->net;
 377	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 378
 379	if (dev == ip6n->fb_tnl_dev)
 380		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 381	else
 382		ip6_tnl_unlink(ip6n, t);
 383	dst_cache_reset(&t->dst_cache);
 384	netdev_put(dev, &t->dev_tracker);
 385}
 386
 387/**
 388 * ip6_tnl_parse_tlv_enc_lim - handle encapsulation limit option
 389 *   @skb: received socket buffer
 390 *   @raw: the ICMPv6 error message data
 391 *
 392 * Return:
 393 *   0 if none was found,
 394 *   else index to encapsulation limit
 395 **/
 396
 397__u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 
 398{
 399	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw;
 400	unsigned int nhoff = raw - skb->data;
 401	unsigned int off = nhoff + sizeof(*ipv6h);
 402	u8 nexthdr = ipv6h->nexthdr;
 403
 404	while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 
 405		struct ipv6_opt_hdr *hdr;
 406		u16 optlen;
 407
 408		if (!pskb_may_pull(skb, off + sizeof(*hdr)))
 409			break;
 410
 411		hdr = (struct ipv6_opt_hdr *)(skb->data + off);
 412		if (nexthdr == NEXTHDR_FRAGMENT) {
 
 
 
 413			optlen = 8;
 414		} else if (nexthdr == NEXTHDR_AUTH) {
 415			optlen = ipv6_authlen(hdr);
 416		} else {
 417			optlen = ipv6_optlen(hdr);
 418		}
 419
 420		if (!pskb_may_pull(skb, off + optlen))
 421			break;
 422
 423		hdr = (struct ipv6_opt_hdr *)(skb->data + off);
 424		if (nexthdr == NEXTHDR_FRAGMENT) {
 425			struct frag_hdr *frag_hdr = (struct frag_hdr *)hdr;
 426
 427			if (frag_hdr->frag_off)
 428				break;
 429		}
 430		if (nexthdr == NEXTHDR_DEST) {
 431			u16 i = 2;
 432
 433			while (1) {
 434				struct ipv6_tlv_tnl_enc_lim *tel;
 435
 436				/* No more room for encapsulation limit */
 437				if (i + sizeof(*tel) > optlen)
 438					break;
 439
 440				tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i);
 441				/* return index of option if found and valid */
 442				if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 443				    tel->length == 1)
 444					return i + off - nhoff;
 445				/* else jump to next option */
 446				if (tel->type)
 447					i += tel->length + 2;
 448				else
 449					i++;
 450			}
 451		}
 452		nexthdr = hdr->nexthdr;
 453		off += optlen;
 454	}
 455	return 0;
 456}
 457EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 458
 459/* ip6_tnl_err() should handle errors in the tunnel according to the
 460 * specifications in RFC 2473.
 461 */
 
 
 
 
 
 462static int
 463ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 464	    u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 465{
 466	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
 467	struct net *net = dev_net(skb->dev);
 
 468	u8 rel_type = ICMPV6_DEST_UNREACH;
 469	u8 rel_code = ICMPV6_ADDR_UNREACH;
 470	__u32 rel_info = 0;
 471	struct ip6_tnl *t;
 472	int err = -ENOENT;
 473	int rel_msg = 0;
 474	u8 tproto;
 475	__u16 len;
 476
 477	/* If the packet doesn't contain the original IPv6 header we are
 478	   in trouble since we might need the source address for further
 479	   processing of the error. */
 480
 481	rcu_read_lock();
 482	t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr);
 483	if (!t)
 484		goto out;
 485
 486	tproto = READ_ONCE(t->parms.proto);
 487	if (tproto != ipproto && tproto != 0)
 488		goto out;
 489
 490	err = 0;
 491
 492	switch (*type) {
 
 
 
 493	case ICMPV6_DEST_UNREACH:
 494		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 495				    t->parms.name);
 
 
 496		rel_msg = 1;
 497		break;
 498	case ICMPV6_TIME_EXCEED:
 499		if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 500			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 501					    t->parms.name);
 
 
 
 502			rel_msg = 1;
 503		}
 504		break;
 505	case ICMPV6_PARAMPROB: {
 506		struct ipv6_tlv_tnl_enc_lim *tel;
 507		__u32 teli;
 508
 509		teli = 0;
 510		if ((*code) == ICMPV6_HDR_FIELD)
 511			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 512
 513		if (teli && teli == *info - 2) {
 514			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 515			if (tel->encap_limit == 0) {
 516				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 517						    t->parms.name);
 
 
 
 518				rel_msg = 1;
 519			}
 520		} else {
 521			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 522					    t->parms.name);
 
 523		}
 524		break;
 525	}
 526	case ICMPV6_PKT_TOOBIG: {
 527		__u32 mtu;
 528
 529		ip6_update_pmtu(skb, net, htonl(*info), 0, 0,
 530				sock_net_uid(net, NULL));
 531		mtu = *info - offset;
 532		if (mtu < IPV6_MIN_MTU)
 533			mtu = IPV6_MIN_MTU;
 534		len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
 535		if (len > mtu) {
 
 536			rel_type = ICMPV6_PKT_TOOBIG;
 537			rel_code = 0;
 538			rel_info = mtu;
 539			rel_msg = 1;
 540		}
 541		break;
 542	}
 543	case NDISC_REDIRECT:
 544		ip6_redirect(skb, net, skb->dev->ifindex, 0,
 545			     sock_net_uid(net, NULL));
 546		break;
 547	}
 548
 549	*type = rel_type;
 550	*code = rel_code;
 551	*info = rel_info;
 552	*msg = rel_msg;
 553
 554out:
 555	rcu_read_unlock();
 556	return err;
 557}
 558
 559static int
 560ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 561	   u8 type, u8 code, int offset, __be32 info)
 562{
 
 
 
 563	__u32 rel_info = ntohl(info);
 
 
 564	const struct iphdr *eiph;
 565	struct sk_buff *skb2;
 566	int err, rel_msg = 0;
 567	u8 rel_type = type;
 568	u8 rel_code = code;
 569	struct rtable *rt;
 570	struct flowi4 fl4;
 571
 572	err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 573			  &rel_msg, &rel_info, offset);
 574	if (err < 0)
 575		return err;
 576
 577	if (rel_msg == 0)
 578		return 0;
 579
 580	switch (rel_type) {
 581	case ICMPV6_DEST_UNREACH:
 582		if (rel_code != ICMPV6_ADDR_UNREACH)
 583			return 0;
 584		rel_type = ICMP_DEST_UNREACH;
 585		rel_code = ICMP_HOST_UNREACH;
 586		break;
 587	case ICMPV6_PKT_TOOBIG:
 588		if (rel_code != 0)
 589			return 0;
 590		rel_type = ICMP_DEST_UNREACH;
 591		rel_code = ICMP_FRAG_NEEDED;
 592		break;
 593	default:
 594		return 0;
 595	}
 596
 597	if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 598		return 0;
 599
 600	skb2 = skb_clone(skb, GFP_ATOMIC);
 601	if (!skb2)
 602		return 0;
 603
 604	skb_dst_drop(skb2);
 605
 606	skb_pull(skb2, offset);
 607	skb_reset_network_header(skb2);
 608	eiph = ip_hdr(skb2);
 609
 610	/* Try to guess incoming interface */
 611	rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr,
 612				   0, 0, 0, IPPROTO_IPIP,
 613				   eiph->tos & INET_DSCP_MASK, 0);
 
 614	if (IS_ERR(rt))
 615		goto out;
 616
 617	skb2->dev = rt->dst.dev;
 618	ip_rt_put(rt);
 619
 620	/* route "incoming" packet */
 621	if (rt->rt_flags & RTCF_LOCAL) {
 
 
 622		rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 623					   eiph->daddr, eiph->saddr, 0, 0,
 
 624					   IPPROTO_IPIP,
 625					   eiph->tos & INET_DSCP_MASK, 0);
 626		if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) {
 
 627			if (!IS_ERR(rt))
 628				ip_rt_put(rt);
 629			goto out;
 630		}
 631		skb_dst_set(skb2, &rt->dst);
 632	} else {
 633		if (ip_route_input(skb2, eiph->daddr, eiph->saddr,
 634				   ip4h_dscp(eiph), skb2->dev) ||
 635		    skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6)
 
 636			goto out;
 637	}
 638
 639	/* change mtu on this route */
 640	if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
 641		if (rel_info > dst_mtu(skb_dst(skb2)))
 642			goto out;
 643
 644		skb_dst_update_pmtu_no_confirm(skb2, rel_info);
 645	}
 646
 647	icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 648
 649out:
 650	kfree_skb(skb2);
 651	return 0;
 652}
 653
 654static int
 655ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 656	   u8 type, u8 code, int offset, __be32 info)
 657{
 658	__u32 rel_info = ntohl(info);
 659	int err, rel_msg = 0;
 660	u8 rel_type = type;
 661	u8 rel_code = code;
 
 
 662
 663	err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 664			  &rel_msg, &rel_info, offset);
 665	if (err < 0)
 666		return err;
 667
 668	if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 669		struct rt6_info *rt;
 670		struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 671
 672		if (!skb2)
 673			return 0;
 674
 675		skb_dst_drop(skb2);
 676		skb_pull(skb2, offset);
 677		skb_reset_network_header(skb2);
 678
 679		/* Try to guess incoming interface */
 680		rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 681				NULL, 0, skb2, 0);
 682
 683		if (rt && rt->dst.dev)
 684			skb2->dev = rt->dst.dev;
 685
 686		icmpv6_send(skb2, rel_type, rel_code, rel_info);
 687
 688		ip6_rt_put(rt);
 
 689
 690		kfree_skb(skb2);
 691	}
 692
 693	return 0;
 694}
 695
 696static int
 697mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 698	    u8 type, u8 code, int offset, __be32 info)
 699{
 700	__u32 rel_info = ntohl(info);
 701	int err, rel_msg = 0;
 702	u8 rel_type = type;
 703	u8 rel_code = code;
 704
 705	err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code,
 706			  &rel_msg, &rel_info, offset);
 707	return err;
 708}
 709
 710static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 711				       const struct ipv6hdr *ipv6h,
 712				       struct sk_buff *skb)
 713{
 714	__u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 715
 716	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 717		ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 718
 719	return IP6_ECN_decapsulate(ipv6h, skb);
 
 720}
 721
 722static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 723				       const struct ipv6hdr *ipv6h,
 724				       struct sk_buff *skb)
 725{
 726	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 727		ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 728
 729	return IP6_ECN_decapsulate(ipv6h, skb);
 
 730}
 731
 732static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 733					       const struct ipv6hdr *ipv6h,
 734					       struct sk_buff *skb)
 735{
 736	/* ECN is not supported in AF_MPLS */
 737	return 0;
 738}
 739
 740__u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 741			     const struct in6_addr *laddr,
 742			     const struct in6_addr *raddr)
 743{
 744	struct __ip6_tnl_parm *p = &t->parms;
 745	int ltype = ipv6_addr_type(laddr);
 746	int rtype = ipv6_addr_type(raddr);
 747	__u32 flags = 0;
 748
 749	if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 750		flags = IP6_TNL_F_CAP_PER_PACKET;
 751	} else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 752		   rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 753		   !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 754		   (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 755		if (ltype&IPV6_ADDR_UNICAST)
 756			flags |= IP6_TNL_F_CAP_XMIT;
 757		if (rtype&IPV6_ADDR_UNICAST)
 758			flags |= IP6_TNL_F_CAP_RCV;
 759	}
 760	return flags;
 761}
 762EXPORT_SYMBOL(ip6_tnl_get_cap);
 763
 764/* called with rcu_read_lock() */
 765int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 766				  const struct in6_addr *laddr,
 767				  const struct in6_addr *raddr)
 768{
 769	struct __ip6_tnl_parm *p = &t->parms;
 770	int ret = 0;
 771	struct net *net = t->net;
 772
 773	if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 774	    ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 775	     (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 776		struct net_device *ldev = NULL;
 777
 778		if (p->link)
 779			ldev = dev_get_by_index_rcu(net, p->link);
 780
 781		if ((ipv6_addr_is_multicast(laddr) ||
 782		     likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false,
 783						    0, IFA_F_TENTATIVE))) &&
 784		    ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) ||
 785		     likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true,
 786						     0, IFA_F_TENTATIVE))))
 787			ret = 1;
 
 788	}
 789	return ret;
 790}
 791EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 792
 793static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
 794			 const struct tnl_ptk_info *tpi,
 795			 struct metadata_dst *tun_dst,
 796			 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 797						const struct ipv6hdr *ipv6h,
 798						struct sk_buff *skb),
 799			 bool log_ecn_err)
 800{
 801	const struct ipv6hdr *ipv6h;
 802	int nh, err;
 803
 804	if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.i_flags) !=
 805	    test_bit(IP_TUNNEL_CSUM_BIT, tpi->flags)) {
 806		DEV_STATS_INC(tunnel->dev, rx_crc_errors);
 807		DEV_STATS_INC(tunnel->dev, rx_errors);
 808		goto drop;
 809	}
 810
 811	if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.i_flags)) {
 812		if (!test_bit(IP_TUNNEL_SEQ_BIT, tpi->flags) ||
 813		    (tunnel->i_seqno &&
 814		     (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
 815			DEV_STATS_INC(tunnel->dev, rx_fifo_errors);
 816			DEV_STATS_INC(tunnel->dev, rx_errors);
 817			goto drop;
 818		}
 819		tunnel->i_seqno = ntohl(tpi->seq) + 1;
 820	}
 821
 822	skb->protocol = tpi->proto;
 
 
 
 
 
 
 
 823
 824	/* Warning: All skb pointers will be invalidated! */
 825	if (tunnel->dev->type == ARPHRD_ETHER) {
 826		if (!pskb_may_pull(skb, ETH_HLEN)) {
 827			DEV_STATS_INC(tunnel->dev, rx_length_errors);
 828			DEV_STATS_INC(tunnel->dev, rx_errors);
 829			goto drop;
 830		}
 831
 832		skb->protocol = eth_type_trans(skb, tunnel->dev);
 833		skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 834	} else {
 835		skb->dev = tunnel->dev;
 836		skb_reset_mac_header(skb);
 837	}
 838
 839	/* Save offset of outer header relative to skb->head,
 840	 * because we are going to reset the network header to the inner header
 841	 * and might change skb->head.
 842	 */
 843	nh = skb_network_header(skb) - skb->head;
 844
 845	skb_reset_network_header(skb);
 
 
 
 846
 847	if (!pskb_inet_may_pull(skb)) {
 848		DEV_STATS_INC(tunnel->dev, rx_length_errors);
 849		DEV_STATS_INC(tunnel->dev, rx_errors);
 850		goto drop;
 851	}
 852
 853	/* Get the outer header. */
 854	ipv6h = (struct ipv6hdr *)(skb->head + nh);
 855
 856	memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 857
 858	__skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
 859
 860	err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
 861	if (unlikely(err)) {
 862		if (log_ecn_err)
 863			net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
 864					     &ipv6h->saddr,
 865					     ipv6_get_dsfield(ipv6h));
 866		if (err > 1) {
 867			DEV_STATS_INC(tunnel->dev, rx_frame_errors);
 868			DEV_STATS_INC(tunnel->dev, rx_errors);
 869			goto drop;
 870		}
 871	}
 
 
 
 
 
 872
 873	dev_sw_netstats_rx_add(tunnel->dev, skb->len);
 
 
 874
 875	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
 876
 877	if (tun_dst)
 878		skb_dst_set(skb, (struct dst_entry *)tun_dst);
 879
 880	gro_cells_receive(&tunnel->gro_cells, skb);
 881	return 0;
 882
 883drop:
 884	if (tun_dst)
 885		dst_release((struct dst_entry *)tun_dst);
 886	kfree_skb(skb);
 887	return 0;
 888}
 889
 890int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
 891		const struct tnl_ptk_info *tpi,
 892		struct metadata_dst *tun_dst,
 893		bool log_ecn_err)
 894{
 895	int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 896				    const struct ipv6hdr *ipv6h,
 897				    struct sk_buff *skb);
 898
 899	dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate;
 900	if (tpi->proto == htons(ETH_P_IP))
 901		dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate;
 902
 903	return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 904			     log_ecn_err);
 905}
 906EXPORT_SYMBOL(ip6_tnl_rcv);
 907
 908static const struct tnl_ptk_info tpi_v6 = {
 909	/* no tunnel info required for ipxip6. */
 910	.proto = htons(ETH_P_IPV6),
 911};
 912
 913static const struct tnl_ptk_info tpi_v4 = {
 914	/* no tunnel info required for ipxip6. */
 915	.proto = htons(ETH_P_IP),
 916};
 917
 918static const struct tnl_ptk_info tpi_mpls = {
 919	/* no tunnel info required for mplsip6. */
 920	.proto = htons(ETH_P_MPLS_UC),
 921};
 922
 923static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
 924		      const struct tnl_ptk_info *tpi,
 925		      int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 926						  const struct ipv6hdr *ipv6h,
 927						  struct sk_buff *skb))
 928{
 929	struct ip6_tnl *t;
 930	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 931	struct metadata_dst *tun_dst = NULL;
 932	int ret = -1;
 933
 934	rcu_read_lock();
 935	t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr);
 936
 937	if (t) {
 938		u8 tproto = READ_ONCE(t->parms.proto);
 939
 940		if (tproto != ipproto && tproto != 0)
 941			goto drop;
 942		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 943			goto drop;
 944		ipv6h = ipv6_hdr(skb);
 945		if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
 946			goto drop;
 947		if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 948			goto drop;
 949		if (t->parms.collect_md) {
 950			IP_TUNNEL_DECLARE_FLAGS(flags) = { };
 951
 952			tun_dst = ipv6_tun_rx_dst(skb, flags, 0, 0);
 953			if (!tun_dst)
 954				goto drop;
 955		}
 956		ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
 957				    log_ecn_error);
 958	}
 959
 960	rcu_read_unlock();
 
 961
 962	return ret;
 963
 964drop:
 965	rcu_read_unlock();
 966	kfree_skb(skb);
 967	return 0;
 968}
 969
 970static int ip4ip6_rcv(struct sk_buff *skb)
 971{
 972	return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
 973			  ip4ip6_dscp_ecn_decapsulate);
 974}
 975
 976static int ip6ip6_rcv(struct sk_buff *skb)
 977{
 978	return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
 979			  ip6ip6_dscp_ecn_decapsulate);
 980}
 981
 982static int mplsip6_rcv(struct sk_buff *skb)
 983{
 984	return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls,
 985			  mplsip6_dscp_ecn_decapsulate);
 986}
 987
 988struct ipv6_tel_txoption {
 989	struct ipv6_txoptions ops;
 990	__u8 dst_opt[8];
 991};
 992
 993static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 994{
 995	memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 996
 997	opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 998	opt->dst_opt[3] = 1;
 999	opt->dst_opt[4] = encap_limit;
1000	opt->dst_opt[5] = IPV6_TLV_PADN;
1001	opt->dst_opt[6] = 1;
1002
1003	opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt;
1004	opt->ops.opt_nflen = 8;
1005}
1006
1007/**
1008 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
1009 *   @t: the outgoing tunnel device
1010 *   @hdr: IPv6 header from the incoming packet
1011 *
1012 * Description:
1013 *   Avoid trivial tunneling loop by checking that tunnel exit-point
1014 *   doesn't match source of incoming packet.
1015 *
1016 * Return:
1017 *   1 if conflict,
1018 *   0 else
1019 **/
1020
1021static inline bool
1022ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
1023{
1024	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
1025}
1026
1027int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
1028		     const struct in6_addr *laddr,
1029		     const struct in6_addr *raddr)
1030{
1031	struct __ip6_tnl_parm *p = &t->parms;
1032	int ret = 0;
1033	struct net *net = t->net;
1034
1035	if (t->parms.collect_md)
1036		return 1;
1037
1038	if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
1039	    ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
1040	     (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
1041		struct net_device *ldev = NULL;
1042
1043		rcu_read_lock();
1044		if (p->link)
1045			ldev = dev_get_by_index_rcu(net, p->link);
1046
1047		if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false,
1048						      0, IFA_F_TENTATIVE)))
1049			pr_warn_ratelimited("%s xmit: Local address not yet configured!\n",
1050					    p->name);
1051		else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) &&
1052			 !ipv6_addr_is_multicast(raddr) &&
1053			 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev,
1054							  true, 0, IFA_F_TENTATIVE)))
1055			pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n",
1056					    p->name);
1057		else
1058			ret = 1;
1059		rcu_read_unlock();
1060	}
1061	return ret;
1062}
1063EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
1064
1065/**
1066 * ip6_tnl_xmit - encapsulate packet and send
1067 *   @skb: the outgoing socket buffer
1068 *   @dev: the outgoing tunnel device
1069 *   @dsfield: dscp code for outer header
1070 *   @fl6: flow of tunneled packet
1071 *   @encap_limit: encapsulation limit
1072 *   @pmtu: Path MTU is stored if packet is too big
1073 *   @proto: next header value
1074 *
1075 * Description:
1076 *   Build new header and do some sanity checks on the packet before sending
1077 *   it.
1078 *
1079 * Return:
1080 *   0 on success
1081 *   -1 fail
1082 *   %-EMSGSIZE message too big. return mtu in this case.
1083 **/
1084
1085int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1086		 struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1087		 __u8 proto)
 
 
 
1088{
 
1089	struct ip6_tnl *t = netdev_priv(dev);
1090	struct net *net = t->net;
1091	struct ipv6hdr *ipv6h;
1092	struct ipv6_tel_txoption opt;
1093	struct dst_entry *dst = NULL, *ndst = NULL;
1094	struct net_device *tdev;
1095	int mtu;
1096	unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0;
1097	unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
1098	unsigned int max_headroom = psh_hlen;
1099	__be16 payload_protocol;
1100	bool use_cache = false;
1101	u8 hop_limit;
1102	int err = -1;
 
1103
1104	payload_protocol = skb_protocol(skb, true);
1105
1106	if (t->parms.collect_md) {
1107		hop_limit = skb_tunnel_info(skb)->key.ttl;
1108		goto route_lookup;
1109	} else {
1110		hop_limit = t->parms.hop_limit;
1111	}
1112
1113	/* NBMA tunnel */
1114	if (ipv6_addr_any(&t->parms.raddr)) {
1115		if (payload_protocol == htons(ETH_P_IPV6)) {
1116			struct in6_addr *addr6;
1117			struct neighbour *neigh;
1118			int addr_type;
1119
1120			if (!skb_dst(skb))
1121				goto tx_err_link_failure;
1122
1123			neigh = dst_neigh_lookup(skb_dst(skb),
1124						 &ipv6_hdr(skb)->daddr);
1125			if (!neigh)
1126				goto tx_err_link_failure;
1127
1128			addr6 = (struct in6_addr *)&neigh->primary_key;
1129			addr_type = ipv6_addr_type(addr6);
1130
1131			if (addr_type == IPV6_ADDR_ANY)
1132				addr6 = &ipv6_hdr(skb)->daddr;
1133
1134			memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1135			neigh_release(neigh);
1136		} else if (payload_protocol == htons(ETH_P_IP)) {
1137			const struct rtable *rt = skb_rtable(skb);
1138
1139			if (!rt)
1140				goto tx_err_link_failure;
1141
1142			if (rt->rt_gw_family == AF_INET6)
1143				memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr));
1144		}
1145	} else if (t->parms.proto != 0 && !(t->parms.flags &
1146					    (IP6_TNL_F_USE_ORIG_TCLASS |
1147					     IP6_TNL_F_USE_ORIG_FWMARK))) {
1148		/* enable the cache only if neither the outer protocol nor the
1149		 * routing decision depends on the current inner header value
1150		 */
1151		use_cache = true;
1152	}
1153
1154	if (use_cache)
1155		dst = dst_cache_get(&t->dst_cache);
1156
1157	if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1158		goto tx_err_link_failure;
1159
1160	if (!dst) {
1161route_lookup:
1162		/* add dsfield to flowlabel for route lookup */
1163		fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel);
1164
1165		dst = ip6_route_output(net, NULL, fl6);
1166
1167		if (dst->error)
1168			goto tx_err_link_failure;
1169		dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1170		if (IS_ERR(dst)) {
1171			err = PTR_ERR(dst);
1172			dst = NULL;
1173			goto tx_err_link_failure;
1174		}
1175		if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) &&
1176		    ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
1177				       &fl6->daddr, 0, &fl6->saddr))
1178			goto tx_err_link_failure;
1179		ndst = dst;
1180	}
1181
1182	tdev = dst->dev;
1183
1184	if (tdev == dev) {
1185		DEV_STATS_INC(dev, collisions);
1186		net_warn_ratelimited("%s: Local routing loop detected!\n",
1187				     t->parms.name);
 
 
1188		goto tx_err_dst_release;
1189	}
1190	mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen;
1191	if (encap_limit >= 0) {
1192		max_headroom += 8;
1193		mtu -= 8;
1194	}
1195	mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ?
1196		       IPV6_MIN_MTU : IPV4_MIN_MTU);
1197
1198	skb_dst_update_pmtu_no_confirm(skb, mtu);
1199	if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) {
1200		*pmtu = mtu;
1201		err = -EMSGSIZE;
1202		goto tx_err_dst_release;
1203	}
1204
1205	if (t->err_count > 0) {
1206		if (time_before(jiffies,
1207				t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1208			t->err_count--;
1209
1210			dst_link_failure(skb);
1211		} else {
1212			t->err_count = 0;
1213		}
1214	}
1215
1216	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1217
1218	/*
1219	 * Okay, now see if we can stuff it in the buffer as-is.
1220	 */
1221	max_headroom += LL_RESERVED_SPACE(tdev);
1222
1223	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1224	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1225		struct sk_buff *new_skb;
1226
1227		new_skb = skb_realloc_headroom(skb, max_headroom);
1228		if (!new_skb)
1229			goto tx_err_dst_release;
1230
1231		if (skb->sk)
1232			skb_set_owner_w(new_skb, skb->sk);
1233		consume_skb(skb);
1234		skb = new_skb;
1235	}
 
 
1236
1237	if (t->parms.collect_md) {
1238		if (t->encap.type != TUNNEL_ENCAP_NONE)
1239			goto tx_err_dst_release;
1240	} else {
1241		if (use_cache && ndst)
1242			dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1243	}
1244	skb_dst_set(skb, dst);
1245
1246	if (hop_limit == 0) {
1247		if (payload_protocol == htons(ETH_P_IP))
1248			hop_limit = ip_hdr(skb)->ttl;
1249		else if (payload_protocol == htons(ETH_P_IPV6))
1250			hop_limit = ipv6_hdr(skb)->hop_limit;
1251		else
1252			hop_limit = ip6_dst_hoplimit(dst);
1253	}
1254
1255	/* Calculate max headroom for all the headers and adjust
1256	 * needed_headroom if necessary.
1257	 */
1258	max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1259			+ dst->header_len + t->hlen;
1260	if (max_headroom > READ_ONCE(dev->needed_headroom))
1261		WRITE_ONCE(dev->needed_headroom, max_headroom);
1262
1263	err = ip6_tnl_encap(skb, t, &proto, fl6);
1264	if (err)
1265		return err;
1266
 
1267	if (encap_limit >= 0) {
1268		init_tel_txopt(&opt, encap_limit);
1269		ipv6_push_frag_opts(skb, &opt.ops, &proto);
1270	}
1271
1272	skb_push(skb, sizeof(struct ipv6hdr));
1273	skb_reset_network_header(skb);
1274	ipv6h = ipv6_hdr(skb);
1275	ip6_flow_hdr(ipv6h, dsfield,
1276		     ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1277	ipv6h->hop_limit = hop_limit;
 
1278	ipv6h->nexthdr = proto;
1279	ipv6h->saddr = fl6->saddr;
1280	ipv6h->daddr = fl6->daddr;
1281	ip6tunnel_xmit(NULL, skb, dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
1282	return 0;
1283tx_err_link_failure:
1284	DEV_STATS_INC(dev, tx_carrier_errors);
1285	dst_link_failure(skb);
1286tx_err_dst_release:
1287	dst_release(dst);
1288	return err;
1289}
1290EXPORT_SYMBOL(ip6_tnl_xmit);
1291
1292static inline int
1293ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev,
1294		u8 protocol)
1295{
1296	struct ip6_tnl *t = netdev_priv(dev);
1297	struct ipv6hdr *ipv6h;
1298	const struct iphdr  *iph;
1299	int encap_limit = -1;
1300	__u16 offset;
1301	struct flowi6 fl6;
1302	__u8 dsfield, orig_dsfield;
1303	__u32 mtu;
1304	u8 tproto;
1305	int err;
1306
1307	tproto = READ_ONCE(t->parms.proto);
1308	if (tproto != protocol && tproto != 0)
1309		return -1;
1310
1311	if (t->parms.collect_md) {
1312		struct ip_tunnel_info *tun_info;
1313		const struct ip_tunnel_key *key;
1314
1315		tun_info = skb_tunnel_info(skb);
1316		if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1317			     ip_tunnel_info_af(tun_info) != AF_INET6))
1318			return -1;
1319		key = &tun_info->key;
1320		memset(&fl6, 0, sizeof(fl6));
1321		fl6.flowi6_proto = protocol;
1322		fl6.saddr = key->u.ipv6.src;
1323		fl6.daddr = key->u.ipv6.dst;
1324		fl6.flowlabel = key->label;
1325		dsfield =  key->tos;
1326		switch (protocol) {
1327		case IPPROTO_IPIP:
1328			iph = ip_hdr(skb);
1329			orig_dsfield = ipv4_get_dsfield(iph);
1330			break;
1331		case IPPROTO_IPV6:
1332			ipv6h = ipv6_hdr(skb);
1333			orig_dsfield = ipv6_get_dsfield(ipv6h);
1334			break;
1335		default:
1336			orig_dsfield = dsfield;
1337			break;
1338		}
1339	} else {
1340		if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1341			encap_limit = t->parms.encap_limit;
1342		if (protocol == IPPROTO_IPV6) {
1343			offset = ip6_tnl_parse_tlv_enc_lim(skb,
1344						skb_network_header(skb));
1345			/* ip6_tnl_parse_tlv_enc_lim() might have
1346			 * reallocated skb->head
1347			 */
1348			if (offset > 0) {
1349				struct ipv6_tlv_tnl_enc_lim *tel;
1350
1351				tel = (void *)&skb_network_header(skb)[offset];
1352				if (tel->encap_limit == 0) {
1353					icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
1354							ICMPV6_HDR_FIELD, offset + 2);
1355					return -1;
1356				}
1357				encap_limit = tel->encap_limit - 1;
1358			}
1359		}
1360
1361		memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1362		fl6.flowi6_proto = protocol;
 
1363
1364		if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1365			fl6.flowi6_mark = skb->mark;
1366		else
1367			fl6.flowi6_mark = t->parms.fwmark;
1368		switch (protocol) {
1369		case IPPROTO_IPIP:
1370			iph = ip_hdr(skb);
1371			orig_dsfield = ipv4_get_dsfield(iph);
1372			if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1373				dsfield = orig_dsfield;
1374			else
1375				dsfield = ip6_tclass(t->parms.flowinfo);
1376			break;
1377		case IPPROTO_IPV6:
1378			ipv6h = ipv6_hdr(skb);
1379			orig_dsfield = ipv6_get_dsfield(ipv6h);
1380			if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1381				dsfield = orig_dsfield;
1382			else
1383				dsfield = ip6_tclass(t->parms.flowinfo);
1384			if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1385				fl6.flowlabel |= ip6_flowlabel(ipv6h);
1386			break;
1387		default:
1388			orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo);
1389			break;
1390		}
1391	}
1392
1393	fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1394	dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield);
1395
1396	if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
 
 
 
 
 
 
 
 
 
 
 
 
 
1397		return -1;
1398
1399	skb_set_inner_ipproto(skb, protocol);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1400
1401	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1402			   protocol);
1403	if (err != 0) {
1404		/* XXX: send ICMP error even if DF is not set. */
1405		if (err == -EMSGSIZE)
1406			switch (protocol) {
1407			case IPPROTO_IPIP:
1408				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1409					      ICMP_FRAG_NEEDED, htonl(mtu));
1410				break;
1411			case IPPROTO_IPV6:
1412				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1413				break;
1414			default:
1415				break;
1416			}
1417		return -1;
1418	}
1419
1420	return 0;
1421}
1422
1423static netdev_tx_t
1424ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1425{
1426	struct ip6_tnl *t = netdev_priv(dev);
1427	u8 ipproto;
1428	int ret;
1429
1430	if (!pskb_inet_may_pull(skb))
1431		goto tx_err;
1432
1433	switch (skb->protocol) {
1434	case htons(ETH_P_IP):
1435		ipproto = IPPROTO_IPIP;
1436		break;
1437	case htons(ETH_P_IPV6):
1438		if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb)))
1439			goto tx_err;
1440		ipproto = IPPROTO_IPV6;
1441		break;
1442	case htons(ETH_P_MPLS_UC):
1443		ipproto = IPPROTO_MPLS;
1444		break;
1445	default:
1446		goto tx_err;
1447	}
1448
1449	ret = ipxip6_tnl_xmit(skb, dev, ipproto);
1450	if (ret < 0)
1451		goto tx_err;
1452
1453	return NETDEV_TX_OK;
1454
1455tx_err:
1456	DEV_STATS_INC(dev, tx_errors);
1457	DEV_STATS_INC(dev, tx_dropped);
1458	kfree_skb(skb);
1459	return NETDEV_TX_OK;
1460}
1461
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1462static void ip6_tnl_link_config(struct ip6_tnl *t)
1463{
1464	struct net_device *dev = t->dev;
1465	struct net_device *tdev = NULL;
1466	struct __ip6_tnl_parm *p = &t->parms;
1467	struct flowi6 *fl6 = &t->fl.u.ip6;
1468	int t_hlen;
1469	int mtu;
1470
1471	__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1472	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1473
1474	/* Set up flowi template */
1475	fl6->saddr = p->laddr;
1476	fl6->daddr = p->raddr;
1477	fl6->flowi6_oif = p->link;
1478	fl6->flowlabel = 0;
1479
1480	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1481		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1482	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1483		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1484
1485	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1486	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1487
1488	if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1489		dev->flags |= IFF_POINTOPOINT;
1490	else
1491		dev->flags &= ~IFF_POINTOPOINT;
1492
1493	t->tun_hlen = 0;
1494	t->hlen = t->encap_hlen + t->tun_hlen;
1495	t_hlen = t->hlen + sizeof(struct ipv6hdr);
1496
1497	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1498		int strict = (ipv6_addr_type(&p->raddr) &
1499			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1500
1501		struct rt6_info *rt = rt6_lookup(t->net,
1502						 &p->raddr, &p->laddr,
1503						 p->link, NULL, strict);
1504		if (rt) {
1505			tdev = rt->dst.dev;
1506			ip6_rt_put(rt);
1507		}
1508
1509		if (!tdev && p->link)
1510			tdev = __dev_get_by_index(t->net, p->link);
1511
1512		if (tdev) {
1513			dev->needed_headroom = tdev->hard_header_len +
1514				tdev->needed_headroom + t_hlen;
1515			mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU);
1516
1517			mtu = mtu - t_hlen;
1518			if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1519				mtu -= 8;
1520
1521			if (mtu < IPV6_MIN_MTU)
1522				mtu = IPV6_MIN_MTU;
1523			WRITE_ONCE(dev->mtu, mtu);
1524		}
 
1525	}
1526}
1527
1528/**
1529 * ip6_tnl_change - update the tunnel parameters
1530 *   @t: tunnel to be changed
1531 *   @p: tunnel configuration parameters
1532 *
1533 * Description:
1534 *   ip6_tnl_change() updates the tunnel parameters
1535 **/
1536
1537static void
1538ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1539{
1540	t->parms.laddr = p->laddr;
1541	t->parms.raddr = p->raddr;
1542	t->parms.flags = p->flags;
1543	t->parms.hop_limit = p->hop_limit;
1544	t->parms.encap_limit = p->encap_limit;
1545	t->parms.flowinfo = p->flowinfo;
1546	t->parms.link = p->link;
1547	t->parms.proto = p->proto;
1548	t->parms.fwmark = p->fwmark;
1549	dst_cache_reset(&t->dst_cache);
1550	ip6_tnl_link_config(t);
1551}
1552
1553static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1554{
1555	struct net *net = t->net;
1556	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1557
1558	ip6_tnl_unlink(ip6n, t);
1559	synchronize_net();
1560	ip6_tnl_change(t, p);
1561	ip6_tnl_link(ip6n, t);
1562	netdev_state_change(t->dev);
1563}
1564
1565static void ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1566{
1567	/* for default tnl0 device allow to change only the proto */
1568	t->parms.proto = p->proto;
1569	netdev_state_change(t->dev);
1570}
1571
1572static void
1573ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1574{
1575	p->laddr = u->laddr;
1576	p->raddr = u->raddr;
1577	p->flags = u->flags;
1578	p->hop_limit = u->hop_limit;
1579	p->encap_limit = u->encap_limit;
1580	p->flowinfo = u->flowinfo;
1581	p->link = u->link;
1582	p->proto = u->proto;
1583	memcpy(p->name, u->name, sizeof(u->name));
1584}
1585
1586static void
1587ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1588{
1589	u->laddr = p->laddr;
1590	u->raddr = p->raddr;
1591	u->flags = p->flags;
1592	u->hop_limit = p->hop_limit;
1593	u->encap_limit = p->encap_limit;
1594	u->flowinfo = p->flowinfo;
1595	u->link = p->link;
1596	u->proto = p->proto;
1597	memcpy(u->name, p->name, sizeof(u->name));
1598}
1599
1600/**
1601 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace
1602 *   @dev: virtual device associated with tunnel
1603 *   @ifr: unused
1604 *   @data: parameters passed from userspace
1605 *   @cmd: command to be performed
1606 *
1607 * Description:
1608 *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1609 *   from userspace.
1610 *
1611 *   The possible commands are the following:
1612 *     %SIOCGETTUNNEL: get tunnel parameters for device
1613 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1614 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1615 *     %SIOCDELTUNNEL: delete tunnel
1616 *
1617 *   The fallback device "ip6tnl0", created during module
1618 *   initialization, can be used for creating other tunnel devices.
1619 *
1620 * Return:
1621 *   0 on success,
1622 *   %-EFAULT if unable to copy data to or from userspace,
1623 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1624 *   %-EINVAL if passed tunnel parameters are invalid,
1625 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1626 *   %-ENODEV if attempting to change or delete a nonexisting device
1627 **/
1628
1629static int
1630ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
1631		       void __user *data, int cmd)
1632{
1633	int err = 0;
1634	struct ip6_tnl_parm p;
1635	struct __ip6_tnl_parm p1;
1636	struct ip6_tnl *t = netdev_priv(dev);
1637	struct net *net = t->net;
1638	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1639
1640	memset(&p1, 0, sizeof(p1));
1641
1642	switch (cmd) {
1643	case SIOCGETTUNNEL:
1644		if (dev == ip6n->fb_tnl_dev) {
1645			if (copy_from_user(&p, data, sizeof(p))) {
1646				err = -EFAULT;
1647				break;
1648			}
1649			ip6_tnl_parm_from_user(&p1, &p);
1650			t = ip6_tnl_locate(net, &p1, 0);
1651			if (IS_ERR(t))
1652				t = netdev_priv(dev);
1653		} else {
1654			memset(&p, 0, sizeof(p));
1655		}
1656		ip6_tnl_parm_to_user(&p, &t->parms);
1657		if (copy_to_user(data, &p, sizeof(p)))
 
 
1658			err = -EFAULT;
 
1659		break;
1660	case SIOCADDTUNNEL:
1661	case SIOCCHGTUNNEL:
1662		err = -EPERM;
1663		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1664			break;
1665		err = -EFAULT;
1666		if (copy_from_user(&p, data, sizeof(p)))
1667			break;
1668		err = -EINVAL;
1669		if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1670		    p.proto != 0)
1671			break;
1672		ip6_tnl_parm_from_user(&p1, &p);
1673		t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1674		if (cmd == SIOCCHGTUNNEL) {
1675			if (!IS_ERR(t)) {
1676				if (t->dev != dev) {
1677					err = -EEXIST;
1678					break;
1679				}
1680			} else
1681				t = netdev_priv(dev);
1682			if (dev == ip6n->fb_tnl_dev)
1683				ip6_tnl0_update(t, &p1);
1684			else
1685				ip6_tnl_update(t, &p1);
 
 
1686		}
1687		if (!IS_ERR(t)) {
1688			err = 0;
1689			ip6_tnl_parm_to_user(&p, &t->parms);
1690			if (copy_to_user(data, &p, sizeof(p)))
1691				err = -EFAULT;
1692
1693		} else {
1694			err = PTR_ERR(t);
1695		}
1696		break;
1697	case SIOCDELTUNNEL:
1698		err = -EPERM;
1699		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1700			break;
1701
1702		if (dev == ip6n->fb_tnl_dev) {
1703			err = -EFAULT;
1704			if (copy_from_user(&p, data, sizeof(p)))
1705				break;
1706			err = -ENOENT;
1707			ip6_tnl_parm_from_user(&p1, &p);
1708			t = ip6_tnl_locate(net, &p1, 0);
1709			if (IS_ERR(t))
1710				break;
1711			err = -EPERM;
1712			if (t->dev == ip6n->fb_tnl_dev)
1713				break;
1714			dev = t->dev;
1715		}
1716		err = 0;
1717		unregister_netdevice(dev);
1718		break;
1719	default:
1720		err = -EINVAL;
1721	}
1722	return err;
1723}
1724
1725/**
1726 * ip6_tnl_change_mtu - change mtu manually for tunnel device
1727 *   @dev: virtual device associated with tunnel
1728 *   @new_mtu: the new mtu
1729 *
1730 * Return:
1731 *   0 on success,
1732 *   %-EINVAL if mtu too small
1733 **/
1734
1735int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
 
1736{
1737	struct ip6_tnl *tnl = netdev_priv(dev);
1738	int t_hlen;
1739
1740	t_hlen = tnl->hlen + sizeof(struct ipv6hdr);
1741	if (tnl->parms.proto == IPPROTO_IPV6) {
1742		if (new_mtu < IPV6_MIN_MTU)
1743			return -EINVAL;
1744	} else {
1745		if (new_mtu < ETH_MIN_MTU)
1746			return -EINVAL;
1747	}
1748	if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
1749		if (new_mtu > IP6_MAX_MTU - dev->hard_header_len - t_hlen)
1750			return -EINVAL;
1751	} else {
1752		if (new_mtu > IP_MAX_MTU - dev->hard_header_len - t_hlen)
1753			return -EINVAL;
1754	}
1755	WRITE_ONCE(dev->mtu, new_mtu);
1756	return 0;
1757}
1758EXPORT_SYMBOL(ip6_tnl_change_mtu);
1759
1760int ip6_tnl_get_iflink(const struct net_device *dev)
1761{
1762	struct ip6_tnl *t = netdev_priv(dev);
1763
1764	return READ_ONCE(t->parms.link);
1765}
1766EXPORT_SYMBOL(ip6_tnl_get_iflink);
1767
1768int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
1769			  unsigned int num)
1770{
1771	if (num >= MAX_IPTUN_ENCAP_OPS)
1772		return -ERANGE;
1773
1774	return !cmpxchg((const struct ip6_tnl_encap_ops **)
1775			&ip6tun_encaps[num],
1776			NULL, ops) ? 0 : -1;
1777}
1778EXPORT_SYMBOL(ip6_tnl_encap_add_ops);
1779
1780int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
1781			  unsigned int num)
1782{
1783	int ret;
1784
1785	if (num >= MAX_IPTUN_ENCAP_OPS)
1786		return -ERANGE;
1787
1788	ret = (cmpxchg((const struct ip6_tnl_encap_ops **)
1789		       &ip6tun_encaps[num],
1790		       ops, NULL) == ops) ? 0 : -1;
1791
1792	synchronize_net();
1793
1794	return ret;
1795}
1796EXPORT_SYMBOL(ip6_tnl_encap_del_ops);
1797
1798int ip6_tnl_encap_setup(struct ip6_tnl *t,
1799			struct ip_tunnel_encap *ipencap)
1800{
1801	int hlen;
1802
1803	memset(&t->encap, 0, sizeof(t->encap));
1804
1805	hlen = ip6_encap_hlen(ipencap);
1806	if (hlen < 0)
1807		return hlen;
1808
1809	t->encap.type = ipencap->type;
1810	t->encap.sport = ipencap->sport;
1811	t->encap.dport = ipencap->dport;
1812	t->encap.flags = ipencap->flags;
1813
1814	t->encap_hlen = hlen;
1815	t->hlen = t->encap_hlen + t->tun_hlen;
1816
1817	return 0;
1818}
1819EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup);
1820
1821static const struct net_device_ops ip6_tnl_netdev_ops = {
1822	.ndo_init	= ip6_tnl_dev_init,
1823	.ndo_uninit	= ip6_tnl_dev_uninit,
1824	.ndo_start_xmit = ip6_tnl_start_xmit,
1825	.ndo_siocdevprivate = ip6_tnl_siocdevprivate,
1826	.ndo_change_mtu = ip6_tnl_change_mtu,
1827	.ndo_get_stats64 = dev_get_tstats64,
1828	.ndo_get_iflink = ip6_tnl_get_iflink,
1829};
1830
1831#define IPXIPX_FEATURES (NETIF_F_SG |		\
1832			 NETIF_F_FRAGLIST |	\
1833			 NETIF_F_HIGHDMA |	\
1834			 NETIF_F_GSO_SOFTWARE |	\
1835			 NETIF_F_HW_CSUM)
1836
1837/**
1838 * ip6_tnl_dev_setup - setup virtual tunnel device
1839 *   @dev: virtual device associated with tunnel
1840 *
1841 * Description:
1842 *   Initialize function pointers and device parameters
1843 **/
1844
1845static void ip6_tnl_dev_setup(struct net_device *dev)
1846{
 
 
1847	dev->netdev_ops = &ip6_tnl_netdev_ops;
1848	dev->header_ops = &ip_tunnel_header_ops;
1849	dev->needs_free_netdev = true;
1850	dev->priv_destructor = ip6_dev_free;
1851
1852	dev->type = ARPHRD_TUNNEL6;
 
 
 
 
 
1853	dev->flags |= IFF_NOARP;
1854	dev->addr_len = sizeof(struct in6_addr);
1855	dev->lltx = true;
1856	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1857	netif_keep_dst(dev);
1858
1859	dev->features		|= IPXIPX_FEATURES;
1860	dev->hw_features	|= IPXIPX_FEATURES;
1861
1862	/* This perm addr will be used as interface identifier by IPv6 */
1863	dev->addr_assign_type = NET_ADDR_RANDOM;
1864	eth_random_addr(dev->perm_addr);
1865}
1866
1867
1868/**
1869 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1870 *   @dev: virtual device associated with tunnel
1871 **/
1872
1873static inline int
1874ip6_tnl_dev_init_gen(struct net_device *dev)
1875{
1876	struct ip6_tnl *t = netdev_priv(dev);
1877	int ret;
1878	int t_hlen;
1879
1880	t->dev = dev;
1881	t->net = dev_net(dev);
1882
1883	ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1884	if (ret)
1885		return ret;
1886
1887	ret = gro_cells_init(&t->gro_cells, dev);
1888	if (ret)
1889		goto destroy_dst;
1890
1891	t->tun_hlen = 0;
1892	t->hlen = t->encap_hlen + t->tun_hlen;
1893	t_hlen = t->hlen + sizeof(struct ipv6hdr);
1894
1895	dev->type = ARPHRD_TUNNEL6;
1896	dev->mtu = ETH_DATA_LEN - t_hlen;
1897	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1898		dev->mtu -= 8;
1899	dev->min_mtu = ETH_MIN_MTU;
1900	dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len - t_hlen;
1901
1902	netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
1903	netdev_lockdep_set_classes(dev);
1904	return 0;
1905
1906destroy_dst:
1907	dst_cache_destroy(&t->dst_cache);
1908
1909	return ret;
1910}
1911
1912/**
1913 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1914 *   @dev: virtual device associated with tunnel
1915 **/
1916
1917static int ip6_tnl_dev_init(struct net_device *dev)
1918{
1919	struct ip6_tnl *t = netdev_priv(dev);
1920	int err = ip6_tnl_dev_init_gen(dev);
1921
1922	if (err)
1923		return err;
1924	ip6_tnl_link_config(t);
1925	if (t->parms.collect_md)
1926		netif_keep_dst(dev);
1927	return 0;
1928}
1929
1930/**
1931 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1932 *   @dev: fallback device
1933 *
1934 * Return: 0
1935 **/
1936
1937static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1938{
1939	struct ip6_tnl *t = netdev_priv(dev);
1940	struct net *net = dev_net(dev);
1941	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 
 
 
 
1942
1943	t->parms.proto = IPPROTO_IPV6;
1944
1945	rcu_assign_pointer(ip6n->tnls_wc[0], t);
1946	return 0;
1947}
1948
1949static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[],
1950			    struct netlink_ext_ack *extack)
1951{
1952	u8 proto;
1953
1954	if (!data || !data[IFLA_IPTUN_PROTO])
1955		return 0;
1956
1957	proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1958	if (proto != IPPROTO_IPV6 &&
1959	    proto != IPPROTO_IPIP &&
1960	    proto != 0)
1961		return -EINVAL;
1962
1963	return 0;
1964}
1965
1966static void ip6_tnl_netlink_parms(struct nlattr *data[],
1967				  struct __ip6_tnl_parm *parms)
1968{
1969	memset(parms, 0, sizeof(*parms));
1970
1971	if (!data)
1972		return;
1973
1974	if (data[IFLA_IPTUN_LINK])
1975		parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1976
1977	if (data[IFLA_IPTUN_LOCAL])
1978		parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1979
1980	if (data[IFLA_IPTUN_REMOTE])
1981		parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1982
1983	if (data[IFLA_IPTUN_TTL])
1984		parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1985
1986	if (data[IFLA_IPTUN_ENCAP_LIMIT])
1987		parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1988
1989	if (data[IFLA_IPTUN_FLOWINFO])
1990		parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1991
1992	if (data[IFLA_IPTUN_FLAGS])
1993		parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1994
1995	if (data[IFLA_IPTUN_PROTO])
1996		parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1997
1998	if (data[IFLA_IPTUN_COLLECT_METADATA])
1999		parms->collect_md = true;
2000
2001	if (data[IFLA_IPTUN_FWMARK])
2002		parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
2003}
2004
2005static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
2006			   struct nlattr *tb[], struct nlattr *data[],
2007			   struct netlink_ext_ack *extack)
2008{
2009	struct net *net = dev_net(dev);
2010	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2011	struct ip_tunnel_encap ipencap;
2012	struct ip6_tnl *nt, *t;
2013	int err;
2014
2015	nt = netdev_priv(dev);
2016
2017	if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
2018		err = ip6_tnl_encap_setup(nt, &ipencap);
2019		if (err < 0)
2020			return err;
2021	}
2022
2023	ip6_tnl_netlink_parms(data, &nt->parms);
2024
2025	if (nt->parms.collect_md) {
2026		if (rtnl_dereference(ip6n->collect_md_tun))
2027			return -EEXIST;
2028	} else {
2029		t = ip6_tnl_locate(net, &nt->parms, 0);
2030		if (!IS_ERR(t))
2031			return -EEXIST;
2032	}
2033
2034	err = ip6_tnl_create2(dev);
2035	if (!err && tb[IFLA_MTU])
2036		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2037
2038	return err;
2039}
2040
2041static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
2042			      struct nlattr *data[],
2043			      struct netlink_ext_ack *extack)
2044{
2045	struct ip6_tnl *t = netdev_priv(dev);
2046	struct __ip6_tnl_parm p;
2047	struct net *net = t->net;
2048	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2049	struct ip_tunnel_encap ipencap;
2050
2051	if (dev == ip6n->fb_tnl_dev)
2052		return -EINVAL;
2053
2054	if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
2055		int err = ip6_tnl_encap_setup(t, &ipencap);
2056
2057		if (err < 0)
2058			return err;
2059	}
2060	ip6_tnl_netlink_parms(data, &p);
2061	if (p.collect_md)
2062		return -EINVAL;
2063
2064	t = ip6_tnl_locate(net, &p, 0);
2065	if (!IS_ERR(t)) {
2066		if (t->dev != dev)
2067			return -EEXIST;
2068	} else
2069		t = netdev_priv(dev);
2070
2071	ip6_tnl_update(t, &p);
2072	return 0;
2073}
2074
2075static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
2076{
2077	struct net *net = dev_net(dev);
2078	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2079
2080	if (dev != ip6n->fb_tnl_dev)
2081		unregister_netdevice_queue(dev, head);
2082}
2083
2084static size_t ip6_tnl_get_size(const struct net_device *dev)
2085{
2086	return
2087		/* IFLA_IPTUN_LINK */
2088		nla_total_size(4) +
2089		/* IFLA_IPTUN_LOCAL */
2090		nla_total_size(sizeof(struct in6_addr)) +
2091		/* IFLA_IPTUN_REMOTE */
2092		nla_total_size(sizeof(struct in6_addr)) +
2093		/* IFLA_IPTUN_TTL */
2094		nla_total_size(1) +
2095		/* IFLA_IPTUN_ENCAP_LIMIT */
2096		nla_total_size(1) +
2097		/* IFLA_IPTUN_FLOWINFO */
2098		nla_total_size(4) +
2099		/* IFLA_IPTUN_FLAGS */
2100		nla_total_size(4) +
2101		/* IFLA_IPTUN_PROTO */
2102		nla_total_size(1) +
2103		/* IFLA_IPTUN_ENCAP_TYPE */
2104		nla_total_size(2) +
2105		/* IFLA_IPTUN_ENCAP_FLAGS */
2106		nla_total_size(2) +
2107		/* IFLA_IPTUN_ENCAP_SPORT */
2108		nla_total_size(2) +
2109		/* IFLA_IPTUN_ENCAP_DPORT */
2110		nla_total_size(2) +
2111		/* IFLA_IPTUN_COLLECT_METADATA */
2112		nla_total_size(0) +
2113		/* IFLA_IPTUN_FWMARK */
2114		nla_total_size(4) +
2115		0;
2116}
2117
2118static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
2119{
2120	struct ip6_tnl *tunnel = netdev_priv(dev);
2121	struct __ip6_tnl_parm *parm = &tunnel->parms;
2122
2123	if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
2124	    nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
2125	    nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
2126	    nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
2127	    nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
2128	    nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
2129	    nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
2130	    nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) ||
2131	    nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark))
2132		goto nla_put_failure;
2133
2134	if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
2135	    nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
2136	    nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
2137	    nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
2138		goto nla_put_failure;
2139
2140	if (parm->collect_md)
2141		if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
2142			goto nla_put_failure;
2143
2144	return 0;
2145
2146nla_put_failure:
2147	return -EMSGSIZE;
2148}
2149
2150struct net *ip6_tnl_get_link_net(const struct net_device *dev)
2151{
2152	struct ip6_tnl *tunnel = netdev_priv(dev);
2153
2154	return READ_ONCE(tunnel->net);
2155}
2156EXPORT_SYMBOL(ip6_tnl_get_link_net);
2157
2158static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
2159	[IFLA_IPTUN_LINK]		= { .type = NLA_U32 },
2160	[IFLA_IPTUN_LOCAL]		= { .len = sizeof(struct in6_addr) },
2161	[IFLA_IPTUN_REMOTE]		= { .len = sizeof(struct in6_addr) },
2162	[IFLA_IPTUN_TTL]		= { .type = NLA_U8 },
2163	[IFLA_IPTUN_ENCAP_LIMIT]	= { .type = NLA_U8 },
2164	[IFLA_IPTUN_FLOWINFO]		= { .type = NLA_U32 },
2165	[IFLA_IPTUN_FLAGS]		= { .type = NLA_U32 },
2166	[IFLA_IPTUN_PROTO]		= { .type = NLA_U8 },
2167	[IFLA_IPTUN_ENCAP_TYPE]		= { .type = NLA_U16 },
2168	[IFLA_IPTUN_ENCAP_FLAGS]	= { .type = NLA_U16 },
2169	[IFLA_IPTUN_ENCAP_SPORT]	= { .type = NLA_U16 },
2170	[IFLA_IPTUN_ENCAP_DPORT]	= { .type = NLA_U16 },
2171	[IFLA_IPTUN_COLLECT_METADATA]	= { .type = NLA_FLAG },
2172	[IFLA_IPTUN_FWMARK]		= { .type = NLA_U32 },
2173};
2174
2175static struct rtnl_link_ops ip6_link_ops __read_mostly = {
2176	.kind		= "ip6tnl",
2177	.maxtype	= IFLA_IPTUN_MAX,
2178	.policy		= ip6_tnl_policy,
2179	.priv_size	= sizeof(struct ip6_tnl),
2180	.setup		= ip6_tnl_dev_setup,
2181	.validate	= ip6_tnl_validate,
2182	.newlink	= ip6_tnl_newlink,
2183	.changelink	= ip6_tnl_changelink,
2184	.dellink	= ip6_tnl_dellink,
2185	.get_size	= ip6_tnl_get_size,
2186	.fill_info	= ip6_tnl_fill_info,
2187	.get_link_net	= ip6_tnl_get_link_net,
2188};
2189
2190static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
2191	.handler	= ip4ip6_rcv,
2192	.err_handler	= ip4ip6_err,
2193	.priority	=	1,
2194};
2195
2196static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
2197	.handler	= ip6ip6_rcv,
2198	.err_handler	= ip6ip6_err,
2199	.priority	=	1,
2200};
2201
2202static struct xfrm6_tunnel mplsip6_handler __read_mostly = {
2203	.handler	= mplsip6_rcv,
2204	.err_handler	= mplsip6_err,
2205	.priority	=	1,
2206};
2207
2208static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list)
2209{
2210	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2211	struct net_device *dev, *aux;
2212	int h;
2213	struct ip6_tnl *t;
 
2214
2215	for_each_netdev_safe(net, dev, aux)
2216		if (dev->rtnl_link_ops == &ip6_link_ops)
2217			unregister_netdevice_queue(dev, list);
2218
2219	for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) {
2220		t = rtnl_dereference(ip6n->tnls_r_l[h]);
2221		while (t) {
2222			/* If dev is in the same netns, it has already
2223			 * been added to the list by the previous loop.
2224			 */
2225			if (!net_eq(dev_net(t->dev), net))
2226				unregister_netdevice_queue(t->dev, list);
2227			t = rtnl_dereference(t->next);
2228		}
2229	}
2230
2231	t = rtnl_dereference(ip6n->tnls_wc[0]);
2232	while (t) {
2233		/* If dev is in the same netns, it has already
2234		 * been added to the list by the previous loop.
2235		 */
2236		if (!net_eq(dev_net(t->dev), net))
2237			unregister_netdevice_queue(t->dev, list);
2238		t = rtnl_dereference(t->next);
2239	}
2240}
2241
2242static int __net_init ip6_tnl_init_net(struct net *net)
2243{
2244	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2245	struct ip6_tnl *t = NULL;
2246	int err;
2247
2248	ip6n->tnls[0] = ip6n->tnls_wc;
2249	ip6n->tnls[1] = ip6n->tnls_r_l;
2250
2251	if (!net_has_fallback_tunnels(net))
2252		return 0;
2253	err = -ENOMEM;
2254	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
2255					NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
2256
2257	if (!ip6n->fb_tnl_dev)
2258		goto err_alloc_dev;
2259	dev_net_set(ip6n->fb_tnl_dev, net);
2260	ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
2261	/* FB netdevice is special: we have one, and only one per netns.
2262	 * Allowing to move it to another netns is clearly unsafe.
2263	 */
2264	ip6n->fb_tnl_dev->netns_local = true;
2265
2266	err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
2267	if (err < 0)
2268		goto err_register;
2269
2270	err = register_netdev(ip6n->fb_tnl_dev);
2271	if (err < 0)
2272		goto err_register;
2273
2274	t = netdev_priv(ip6n->fb_tnl_dev);
2275
2276	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
2277	return 0;
2278
2279err_register:
2280	free_netdev(ip6n->fb_tnl_dev);
2281err_alloc_dev:
2282	return err;
2283}
2284
2285static void __net_exit ip6_tnl_exit_batch_rtnl(struct list_head *net_list,
2286					       struct list_head *dev_to_kill)
2287{
2288	struct net *net;
2289
2290	ASSERT_RTNL();
2291	list_for_each_entry(net, net_list, exit_list)
2292		ip6_tnl_destroy_tunnels(net, dev_to_kill);
2293}
2294
2295static struct pernet_operations ip6_tnl_net_ops = {
2296	.init = ip6_tnl_init_net,
2297	.exit_batch_rtnl = ip6_tnl_exit_batch_rtnl,
2298	.id   = &ip6_tnl_net_id,
2299	.size = sizeof(struct ip6_tnl_net),
2300};
2301
2302/**
2303 * ip6_tunnel_init - register protocol and reserve needed resources
2304 *
2305 * Return: 0 on success
2306 **/
2307
2308static int __init ip6_tunnel_init(void)
2309{
2310	int  err;
2311
2312	if (!ipv6_mod_enabled())
2313		return -EOPNOTSUPP;
2314
2315	err = register_pernet_device(&ip6_tnl_net_ops);
2316	if (err < 0)
2317		goto out_pernet;
2318
2319	err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
2320	if (err < 0) {
2321		pr_err("%s: can't register ip4ip6\n", __func__);
2322		goto out_ip4ip6;
2323	}
2324
2325	err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
2326	if (err < 0) {
2327		pr_err("%s: can't register ip6ip6\n", __func__);
2328		goto out_ip6ip6;
2329	}
2330
2331	if (ip6_tnl_mpls_supported()) {
2332		err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS);
2333		if (err < 0) {
2334			pr_err("%s: can't register mplsip6\n", __func__);
2335			goto out_mplsip6;
2336		}
2337	}
2338
2339	err = rtnl_link_register(&ip6_link_ops);
2340	if (err < 0)
2341		goto rtnl_link_failed;
2342
2343	return 0;
2344
2345rtnl_link_failed:
2346	if (ip6_tnl_mpls_supported())
2347		xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS);
2348out_mplsip6:
2349	xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
2350out_ip6ip6:
2351	xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
2352out_ip4ip6:
2353	unregister_pernet_device(&ip6_tnl_net_ops);
2354out_pernet:
2355	return err;
2356}
2357
2358/**
2359 * ip6_tunnel_cleanup - free resources and unregister protocol
2360 **/
2361
2362static void __exit ip6_tunnel_cleanup(void)
2363{
2364	rtnl_link_unregister(&ip6_link_ops);
2365	if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
2366		pr_info("%s: can't deregister ip4ip6\n", __func__);
2367
2368	if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2369		pr_info("%s: can't deregister ip6ip6\n", __func__);
2370
2371	if (ip6_tnl_mpls_supported() &&
2372	    xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS))
2373		pr_info("%s: can't deregister mplsip6\n", __func__);
2374	unregister_pernet_device(&ip6_tnl_net_ops);
2375}
2376
2377module_init(ip6_tunnel_init);
2378module_exit(ip6_tunnel_cleanup);