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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);
v3.15
   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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23#include <linux/module.h>
  24#include <linux/capability.h>
  25#include <linux/errno.h>
  26#include <linux/types.h>
  27#include <linux/sockios.h>
  28#include <linux/icmp.h>
  29#include <linux/if.h>
  30#include <linux/in.h>
  31#include <linux/ip.h>
 
  32#include <linux/net.h>
  33#include <linux/in6.h>
  34#include <linux/netdevice.h>
  35#include <linux/if_arp.h>
  36#include <linux/icmpv6.h>
  37#include <linux/init.h>
  38#include <linux/route.h>
  39#include <linux/rtnetlink.h>
  40#include <linux/netfilter_ipv6.h>
  41#include <linux/slab.h>
  42#include <linux/hash.h>
  43#include <linux/etherdevice.h>
  44
  45#include <asm/uaccess.h>
  46#include <linux/atomic.h>
  47
  48#include <net/icmp.h>
  49#include <net/ip.h>
  50#include <net/ip_tunnels.h>
  51#include <net/ipv6.h>
  52#include <net/ip6_route.h>
  53#include <net/addrconf.h>
  54#include <net/ip6_tunnel.h>
  55#include <net/xfrm.h>
  56#include <net/dsfield.h>
  57#include <net/inet_ecn.h>
  58#include <net/net_namespace.h>
  59#include <net/netns/generic.h>
  60
  61MODULE_AUTHOR("Ville Nuorvala");
  62MODULE_DESCRIPTION("IPv6 tunneling device");
  63MODULE_LICENSE("GPL");
  64MODULE_ALIAS_NETDEV("ip6tnl0");
  65
  66#ifdef IP6_TNL_DEBUG
  67#define IP6_TNL_TRACE(x...) pr_debug("%s:" x "\n", __func__)
  68#else
  69#define IP6_TNL_TRACE(x...) do {;} while(0)
  70#endif
  71
  72#define HASH_SIZE_SHIFT  5
  73#define HASH_SIZE (1 << HASH_SIZE_SHIFT)
  74
  75static bool log_ecn_error = true;
  76module_param(log_ecn_error, bool, 0644);
  77MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  78
  79static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  80{
  81	u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  82
  83	return hash_32(hash, HASH_SIZE_SHIFT);
  84}
 
  85
  86static int ip6_tnl_dev_init(struct net_device *dev);
  87static void ip6_tnl_dev_setup(struct net_device *dev);
  88static struct rtnl_link_ops ip6_link_ops __read_mostly;
  89
  90static int ip6_tnl_net_id __read_mostly;
  91struct ip6_tnl_net {
  92	/* the IPv6 tunnel fallback device */
  93	struct net_device *fb_tnl_dev;
  94	/* lists for storing tunnels in use */
  95	struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
  96	struct ip6_tnl __rcu *tnls_wc[1];
  97	struct ip6_tnl __rcu **tnls[2];
  98};
  99
 
 
 
 
 
 
 
 
 100static struct net_device_stats *ip6_get_stats(struct net_device *dev)
 101{
 102	struct pcpu_sw_netstats tmp, sum = { 0 };
 103	int i;
 104
 105	for_each_possible_cpu(i) {
 106		unsigned int start;
 107		const struct pcpu_sw_netstats *tstats =
 108						   per_cpu_ptr(dev->tstats, i);
 109
 110		do {
 111			start = u64_stats_fetch_begin_irq(&tstats->syncp);
 112			tmp.rx_packets = tstats->rx_packets;
 113			tmp.rx_bytes = tstats->rx_bytes;
 114			tmp.tx_packets = tstats->tx_packets;
 115			tmp.tx_bytes =  tstats->tx_bytes;
 116		} while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
 117
 118		sum.rx_packets += tmp.rx_packets;
 119		sum.rx_bytes   += tmp.rx_bytes;
 120		sum.tx_packets += tmp.tx_packets;
 121		sum.tx_bytes   += tmp.tx_bytes;
 122	}
 123	dev->stats.rx_packets = sum.rx_packets;
 124	dev->stats.rx_bytes   = sum.rx_bytes;
 125	dev->stats.tx_packets = sum.tx_packets;
 126	dev->stats.tx_bytes   = sum.tx_bytes;
 127	return &dev->stats;
 128}
 129
 130/*
 131 * Locking : hash tables are protected by RCU and RTNL
 132 */
 133
 134struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
 135{
 136	struct dst_entry *dst = t->dst_cache;
 137
 138	if (dst && dst->obsolete &&
 139	    dst->ops->check(dst, t->dst_cookie) == NULL) {
 140		t->dst_cache = NULL;
 141		dst_release(dst);
 142		return NULL;
 143	}
 144
 145	return dst;
 146}
 147EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
 148
 149void ip6_tnl_dst_reset(struct ip6_tnl *t)
 150{
 151	dst_release(t->dst_cache);
 152	t->dst_cache = NULL;
 153}
 154EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
 155
 156void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
 157{
 158	struct rt6_info *rt = (struct rt6_info *) dst;
 159	t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
 160	dst_release(t->dst_cache);
 161	t->dst_cache = dst;
 162}
 163EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
 164
 165/**
 166 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
 167 *   @remote: the address of the tunnel exit-point
 168 *   @local: the address of the tunnel entry-point
 169 *
 170 * Return:
 171 *   tunnel matching given end-points if found,
 172 *   else fallback tunnel if its device is up,
 173 *   else %NULL
 174 **/
 175
 176#define for_each_ip6_tunnel_rcu(start) \
 177	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
 178
 179static struct ip6_tnl *
 180ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
 181{
 182	unsigned int hash = HASH(remote, local);
 
 183	struct ip6_tnl *t;
 184	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 185
 186	for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 187		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 188		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 189		    (t->dev->flags & IFF_UP))
 190			return t;
 191	}
 192	t = rcu_dereference(ip6n->tnls_wc[0]);
 193	if (t && (t->dev->flags & IFF_UP))
 194		return t;
 195
 196	return NULL;
 197}
 198
 199/**
 200 * ip6_tnl_bucket - get head of list matching given tunnel parameters
 201 *   @p: parameters containing tunnel end-points
 202 *
 203 * Description:
 204 *   ip6_tnl_bucket() returns the head of the list matching the
 205 *   &struct in6_addr entries laddr and raddr in @p.
 206 *
 207 * Return: head of IPv6 tunnel list
 208 **/
 209
 210static struct ip6_tnl __rcu **
 211ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 212{
 213	const struct in6_addr *remote = &p->raddr;
 214	const struct in6_addr *local = &p->laddr;
 215	unsigned int h = 0;
 216	int prio = 0;
 217
 218	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 219		prio = 1;
 220		h = HASH(remote, local);
 221	}
 222	return &ip6n->tnls[prio][h];
 223}
 224
 225/**
 226 * ip6_tnl_link - add tunnel to hash table
 227 *   @t: tunnel to be added
 228 **/
 229
 230static void
 231ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 232{
 233	struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
 234
 235	rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 236	rcu_assign_pointer(*tp, t);
 237}
 238
 239/**
 240 * ip6_tnl_unlink - remove tunnel from hash table
 241 *   @t: tunnel to be removed
 242 **/
 243
 244static void
 245ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
 246{
 247	struct ip6_tnl __rcu **tp;
 248	struct ip6_tnl *iter;
 249
 250	for (tp = ip6_tnl_bucket(ip6n, &t->parms);
 251	     (iter = rtnl_dereference(*tp)) != NULL;
 252	     tp = &iter->next) {
 253		if (t == iter) {
 254			rcu_assign_pointer(*tp, t->next);
 255			break;
 256		}
 257	}
 258}
 259
 260static void ip6_dev_free(struct net_device *dev)
 261{
 262	free_percpu(dev->tstats);
 263	free_netdev(dev);
 264}
 265
 266static int ip6_tnl_create2(struct net_device *dev)
 267{
 268	struct ip6_tnl *t = netdev_priv(dev);
 269	struct net *net = dev_net(dev);
 270	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 271	int err;
 272
 273	t = netdev_priv(dev);
 274	err = ip6_tnl_dev_init(dev);
 275	if (err < 0)
 276		goto out;
 277
 278	err = register_netdevice(dev);
 279	if (err < 0)
 280		goto out;
 281
 282	strcpy(t->parms.name, dev->name);
 283	dev->rtnl_link_ops = &ip6_link_ops;
 284
 285	dev_hold(dev);
 286	ip6_tnl_link(ip6n, t);
 287	return 0;
 288
 289out:
 290	return err;
 291}
 292
 293/**
 294 * ip6_tnl_create - create a new tunnel
 295 *   @p: tunnel parameters
 296 *   @pt: pointer to new tunnel
 297 *
 298 * Description:
 299 *   Create tunnel matching given parameters.
 300 *
 301 * Return:
 302 *   created tunnel or NULL
 303 **/
 304
 305static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 306{
 307	struct net_device *dev;
 308	struct ip6_tnl *t;
 309	char name[IFNAMSIZ];
 310	int err;
 
 311
 312	if (p->name[0])
 313		strlcpy(name, p->name, IFNAMSIZ);
 314	else
 315		sprintf(name, "ip6tnl%%d");
 316
 317	dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup);
 318	if (dev == NULL)
 319		goto failed;
 320
 321	dev_net_set(dev, net);
 322
 323	t = netdev_priv(dev);
 324	t->parms = *p;
 325	t->net = dev_net(dev);
 326	err = ip6_tnl_create2(dev);
 327	if (err < 0)
 328		goto failed_free;
 329
 
 
 
 
 
 330	return t;
 331
 332failed_free:
 333	ip6_dev_free(dev);
 334failed:
 335	return NULL;
 336}
 337
 338/**
 339 * ip6_tnl_locate - find or create tunnel matching given parameters
 340 *   @p: tunnel parameters
 341 *   @create: != 0 if allowed to create new tunnel if no match found
 342 *
 343 * Description:
 344 *   ip6_tnl_locate() first tries to locate an existing tunnel
 345 *   based on @parms. If this is unsuccessful, but @create is set a new
 346 *   tunnel device is created and registered for use.
 347 *
 348 * Return:
 349 *   matching tunnel or NULL
 350 **/
 351
 352static struct ip6_tnl *ip6_tnl_locate(struct net *net,
 353		struct __ip6_tnl_parm *p, int create)
 354{
 355	const struct in6_addr *remote = &p->raddr;
 356	const struct in6_addr *local = &p->laddr;
 357	struct ip6_tnl __rcu **tp;
 358	struct ip6_tnl *t;
 359	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 360
 361	for (tp = ip6_tnl_bucket(ip6n, p);
 362	     (t = rtnl_dereference(*tp)) != NULL;
 363	     tp = &t->next) {
 364		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 365		    ipv6_addr_equal(remote, &t->parms.raddr))
 366			return t;
 367	}
 368	if (!create)
 369		return NULL;
 370	return ip6_tnl_create(net, p);
 371}
 372
 373/**
 374 * ip6_tnl_dev_uninit - tunnel device uninitializer
 375 *   @dev: the device to be destroyed
 376 *
 377 * Description:
 378 *   ip6_tnl_dev_uninit() removes tunnel from its list
 379 **/
 380
 381static void
 382ip6_tnl_dev_uninit(struct net_device *dev)
 383{
 384	struct ip6_tnl *t = netdev_priv(dev);
 385	struct net *net = t->net;
 386	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 387
 388	if (dev == ip6n->fb_tnl_dev)
 389		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 390	else
 391		ip6_tnl_unlink(ip6n, t);
 392	ip6_tnl_dst_reset(t);
 393	dev_put(dev);
 394}
 395
 396/**
 397 * parse_tvl_tnl_enc_lim - handle encapsulation limit option
 398 *   @skb: received socket buffer
 399 *
 400 * Return:
 401 *   0 if none was found,
 402 *   else index to encapsulation limit
 403 **/
 404
 405__u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 
 406{
 407	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
 408	__u8 nexthdr = ipv6h->nexthdr;
 409	__u16 off = sizeof (*ipv6h);
 410
 411	while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
 412		__u16 optlen = 0;
 413		struct ipv6_opt_hdr *hdr;
 414		if (raw + off + sizeof (*hdr) > skb->data &&
 415		    !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
 416			break;
 417
 418		hdr = (struct ipv6_opt_hdr *) (raw + off);
 419		if (nexthdr == NEXTHDR_FRAGMENT) {
 420			struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
 421			if (frag_hdr->frag_off)
 422				break;
 423			optlen = 8;
 424		} else if (nexthdr == NEXTHDR_AUTH) {
 425			optlen = (hdr->hdrlen + 2) << 2;
 426		} else {
 427			optlen = ipv6_optlen(hdr);
 428		}
 429		if (nexthdr == NEXTHDR_DEST) {
 430			__u16 i = off + 2;
 431			while (1) {
 432				struct ipv6_tlv_tnl_enc_lim *tel;
 433
 434				/* No more room for encapsulation limit */
 435				if (i + sizeof (*tel) > off + optlen)
 436					break;
 437
 438				tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
 439				/* return index of option if found and valid */
 440				if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
 441				    tel->length == 1)
 442					return i;
 443				/* else jump to next option */
 444				if (tel->type)
 445					i += tel->length + 2;
 446				else
 447					i++;
 448			}
 449		}
 450		nexthdr = hdr->nexthdr;
 451		off += optlen;
 452	}
 453	return 0;
 454}
 455EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 456
 457/**
 458 * ip6_tnl_err - tunnel error handler
 459 *
 460 * Description:
 461 *   ip6_tnl_err() should handle errors in the tunnel according
 462 *   to the specifications in RFC 2473.
 463 **/
 464
 465static int
 466ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
 467	    u8 *type, u8 *code, int *msg, __u32 *info, int offset)
 468{
 469	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
 470	struct ip6_tnl *t;
 471	int rel_msg = 0;
 472	u8 rel_type = ICMPV6_DEST_UNREACH;
 473	u8 rel_code = ICMPV6_ADDR_UNREACH;
 474	__u32 rel_info = 0;
 475	__u16 len;
 476	int err = -ENOENT;
 477
 478	/* If the packet doesn't contain the original IPv6 header we are
 479	   in trouble since we might need the source address for further
 480	   processing of the error. */
 481
 482	rcu_read_lock();
 483	if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr,
 484					&ipv6h->saddr)) == NULL)
 485		goto out;
 486
 487	if (t->parms.proto != ipproto && t->parms.proto != 0)
 488		goto out;
 489
 490	err = 0;
 491
 492	switch (*type) {
 493		__u32 teli;
 494		struct ipv6_tlv_tnl_enc_lim *tel;
 495		__u32 mtu;
 496	case ICMPV6_DEST_UNREACH:
 497		net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
 498				     t->parms.name);
 
 
 499		rel_msg = 1;
 500		break;
 501	case ICMPV6_TIME_EXCEED:
 502		if ((*code) == ICMPV6_EXC_HOPLIMIT) {
 503			net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 504					     t->parms.name);
 
 
 
 505			rel_msg = 1;
 506		}
 507		break;
 508	case ICMPV6_PARAMPROB:
 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_warn_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_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 522					     t->parms.name);
 
 523		}
 524		break;
 525	case ICMPV6_PKT_TOOBIG:
 526		mtu = *info - offset;
 527		if (mtu < IPV6_MIN_MTU)
 528			mtu = IPV6_MIN_MTU;
 529		t->dev->mtu = mtu;
 530
 531		if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
 532			rel_type = ICMPV6_PKT_TOOBIG;
 533			rel_code = 0;
 534			rel_info = mtu;
 535			rel_msg = 1;
 536		}
 537		break;
 538	}
 539
 540	*type = rel_type;
 541	*code = rel_code;
 542	*info = rel_info;
 543	*msg = rel_msg;
 544
 545out:
 546	rcu_read_unlock();
 547	return err;
 548}
 549
 550static int
 551ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 552	   u8 type, u8 code, int offset, __be32 info)
 553{
 554	int rel_msg = 0;
 555	u8 rel_type = type;
 556	u8 rel_code = code;
 557	__u32 rel_info = ntohl(info);
 558	int err;
 559	struct sk_buff *skb2;
 560	const struct iphdr *eiph;
 561	struct rtable *rt;
 562	struct flowi4 fl4;
 563
 564	err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
 565			  &rel_msg, &rel_info, offset);
 566	if (err < 0)
 567		return err;
 568
 569	if (rel_msg == 0)
 570		return 0;
 571
 572	switch (rel_type) {
 573	case ICMPV6_DEST_UNREACH:
 574		if (rel_code != ICMPV6_ADDR_UNREACH)
 575			return 0;
 576		rel_type = ICMP_DEST_UNREACH;
 577		rel_code = ICMP_HOST_UNREACH;
 578		break;
 579	case ICMPV6_PKT_TOOBIG:
 580		if (rel_code != 0)
 581			return 0;
 582		rel_type = ICMP_DEST_UNREACH;
 583		rel_code = ICMP_FRAG_NEEDED;
 584		break;
 585	case NDISC_REDIRECT:
 586		rel_type = ICMP_REDIRECT;
 587		rel_code = ICMP_REDIR_HOST;
 588	default:
 589		return 0;
 590	}
 591
 592	if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
 593		return 0;
 594
 595	skb2 = skb_clone(skb, GFP_ATOMIC);
 596	if (!skb2)
 597		return 0;
 598
 599	skb_dst_drop(skb2);
 600
 601	skb_pull(skb2, offset);
 602	skb_reset_network_header(skb2);
 603	eiph = ip_hdr(skb2);
 604
 605	/* Try to guess incoming interface */
 606	rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 607				   eiph->saddr, 0,
 608				   0, 0,
 609				   IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
 610	if (IS_ERR(rt))
 611		goto out;
 612
 613	skb2->dev = rt->dst.dev;
 614
 615	/* route "incoming" packet */
 616	if (rt->rt_flags & RTCF_LOCAL) {
 617		ip_rt_put(rt);
 618		rt = NULL;
 619		rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
 620					   eiph->daddr, eiph->saddr,
 621					   0, 0,
 622					   IPPROTO_IPIP,
 623					   RT_TOS(eiph->tos), 0);
 624		if (IS_ERR(rt) ||
 625		    rt->dst.dev->type != ARPHRD_TUNNEL) {
 626			if (!IS_ERR(rt))
 627				ip_rt_put(rt);
 628			goto out;
 629		}
 630		skb_dst_set(skb2, &rt->dst);
 631	} else {
 632		ip_rt_put(rt);
 633		if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
 634				   skb2->dev) ||
 635		    skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
 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(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
 645	}
 646	if (rel_type == ICMP_REDIRECT)
 647		skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
 648
 649	icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
 650
 651out:
 652	kfree_skb(skb2);
 653	return 0;
 654}
 655
 656static int
 657ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 658	   u8 type, u8 code, int offset, __be32 info)
 659{
 660	int rel_msg = 0;
 661	u8 rel_type = type;
 662	u8 rel_code = code;
 663	__u32 rel_info = ntohl(info);
 664	int err;
 665
 666	err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
 667			  &rel_msg, &rel_info, offset);
 668	if (err < 0)
 669		return err;
 670
 671	if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
 672		struct rt6_info *rt;
 673		struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 674
 675		if (!skb2)
 676			return 0;
 677
 678		skb_dst_drop(skb2);
 679		skb_pull(skb2, offset);
 680		skb_reset_network_header(skb2);
 681
 682		/* Try to guess incoming interface */
 683		rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
 684				NULL, 0, 0);
 685
 686		if (rt && rt->dst.dev)
 687			skb2->dev = rt->dst.dev;
 688
 689		icmpv6_send(skb2, rel_type, rel_code, rel_info);
 690
 691		ip6_rt_put(rt);
 
 692
 693		kfree_skb(skb2);
 694	}
 695
 696	return 0;
 697}
 698
 699static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 700				       const struct ipv6hdr *ipv6h,
 701				       struct sk_buff *skb)
 702{
 703	__u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
 704
 705	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 706		ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
 707
 708	return IP6_ECN_decapsulate(ipv6h, skb);
 
 709}
 710
 711static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
 712				       const struct ipv6hdr *ipv6h,
 713				       struct sk_buff *skb)
 714{
 715	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
 716		ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
 717
 718	return IP6_ECN_decapsulate(ipv6h, skb);
 
 719}
 720
 721__u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 722			     const struct in6_addr *laddr,
 723			     const struct in6_addr *raddr)
 724{
 725	struct __ip6_tnl_parm *p = &t->parms;
 726	int ltype = ipv6_addr_type(laddr);
 727	int rtype = ipv6_addr_type(raddr);
 728	__u32 flags = 0;
 729
 730	if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
 731		flags = IP6_TNL_F_CAP_PER_PACKET;
 732	} else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 733		   rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
 734		   !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
 735		   (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
 736		if (ltype&IPV6_ADDR_UNICAST)
 737			flags |= IP6_TNL_F_CAP_XMIT;
 738		if (rtype&IPV6_ADDR_UNICAST)
 739			flags |= IP6_TNL_F_CAP_RCV;
 740	}
 741	return flags;
 742}
 743EXPORT_SYMBOL(ip6_tnl_get_cap);
 744
 745/* called with rcu_read_lock() */
 746int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 747				  const struct in6_addr *laddr,
 748				  const struct in6_addr *raddr)
 749{
 750	struct __ip6_tnl_parm *p = &t->parms;
 751	int ret = 0;
 752	struct net *net = t->net;
 753
 754	if ((p->flags & IP6_TNL_F_CAP_RCV) ||
 755	    ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
 756	     (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
 757		struct net_device *ldev = NULL;
 758
 759		if (p->link)
 760			ldev = dev_get_by_index_rcu(net, p->link);
 761
 762		if ((ipv6_addr_is_multicast(laddr) ||
 763		     likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
 764		    likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
 765			ret = 1;
 
 766	}
 767	return ret;
 768}
 769EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 770
 771/**
 772 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
 773 *   @skb: received socket buffer
 774 *   @protocol: ethernet protocol ID
 775 *   @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
 776 *
 777 * Return: 0
 778 **/
 779
 780static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
 781		       __u8 ipproto,
 782		       int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
 783						   const struct ipv6hdr *ipv6h,
 784						   struct sk_buff *skb))
 785{
 786	struct ip6_tnl *t;
 787	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 788	int err;
 789
 790	rcu_read_lock();
 791
 792	if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
 793					&ipv6h->daddr)) != NULL) {
 794		struct pcpu_sw_netstats *tstats;
 795
 796		if (t->parms.proto != ipproto && t->parms.proto != 0) {
 797			rcu_read_unlock();
 798			goto discard;
 799		}
 800
 801		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 802			rcu_read_unlock();
 803			goto discard;
 804		}
 805
 806		if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
 807			t->dev->stats.rx_dropped++;
 808			rcu_read_unlock();
 809			goto discard;
 810		}
 
 811		skb->mac_header = skb->network_header;
 812		skb_reset_network_header(skb);
 813		skb->protocol = htons(protocol);
 
 814		memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 815
 816		__skb_tunnel_rx(skb, t->dev, t->net);
 817
 818		err = dscp_ecn_decapsulate(t, ipv6h, skb);
 819		if (unlikely(err)) {
 820			if (log_ecn_error)
 821				net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
 822						     &ipv6h->saddr,
 823						     ipv6_get_dsfield(ipv6h));
 824			if (err > 1) {
 825				++t->dev->stats.rx_frame_errors;
 826				++t->dev->stats.rx_errors;
 827				rcu_read_unlock();
 828				goto discard;
 829			}
 830		}
 831
 832		tstats = this_cpu_ptr(t->dev->tstats);
 833		u64_stats_update_begin(&tstats->syncp);
 834		tstats->rx_packets++;
 835		tstats->rx_bytes += skb->len;
 836		u64_stats_update_end(&tstats->syncp);
 
 
 
 837
 838		netif_rx(skb);
 839
 840		rcu_read_unlock();
 841		return 0;
 842	}
 843	rcu_read_unlock();
 844	return 1;
 845
 846discard:
 847	kfree_skb(skb);
 848	return 0;
 849}
 850
 851static int ip4ip6_rcv(struct sk_buff *skb)
 852{
 853	return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
 854			   ip4ip6_dscp_ecn_decapsulate);
 855}
 856
 857static int ip6ip6_rcv(struct sk_buff *skb)
 858{
 859	return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
 860			   ip6ip6_dscp_ecn_decapsulate);
 861}
 862
 863struct ipv6_tel_txoption {
 864	struct ipv6_txoptions ops;
 865	__u8 dst_opt[8];
 866};
 867
 868static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
 869{
 870	memset(opt, 0, sizeof(struct ipv6_tel_txoption));
 871
 872	opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
 873	opt->dst_opt[3] = 1;
 874	opt->dst_opt[4] = encap_limit;
 875	opt->dst_opt[5] = IPV6_TLV_PADN;
 876	opt->dst_opt[6] = 1;
 877
 878	opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
 879	opt->ops.opt_nflen = 8;
 880}
 881
 882/**
 883 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
 884 *   @t: the outgoing tunnel device
 885 *   @hdr: IPv6 header from the incoming packet
 886 *
 887 * Description:
 888 *   Avoid trivial tunneling loop by checking that tunnel exit-point
 889 *   doesn't match source of incoming packet.
 890 *
 891 * Return:
 892 *   1 if conflict,
 893 *   0 else
 894 **/
 895
 896static inline bool
 897ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 898{
 899	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 900}
 901
 902int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
 903{
 904	struct __ip6_tnl_parm *p = &t->parms;
 905	int ret = 0;
 906	struct net *net = t->net;
 907
 908	if (p->flags & IP6_TNL_F_CAP_XMIT) {
 909		struct net_device *ldev = NULL;
 910
 911		rcu_read_lock();
 912		if (p->link)
 913			ldev = dev_get_by_index_rcu(net, p->link);
 914
 915		if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0)))
 916			pr_warn("%s xmit: Local address not yet configured!\n",
 917				p->name);
 
 918		else if (!ipv6_addr_is_multicast(&p->raddr) &&
 919			 unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0)))
 920			pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
 921				p->name);
 
 
 922		else
 923			ret = 1;
 924		rcu_read_unlock();
 925	}
 926	return ret;
 927}
 928EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
 929
 930/**
 931 * ip6_tnl_xmit2 - encapsulate packet and send
 932 *   @skb: the outgoing socket buffer
 933 *   @dev: the outgoing tunnel device
 934 *   @dsfield: dscp code for outer header
 935 *   @fl: flow of tunneled packet
 936 *   @encap_limit: encapsulation limit
 937 *   @pmtu: Path MTU is stored if packet is too big
 938 *
 939 * Description:
 940 *   Build new header and do some sanity checks on the packet before sending
 941 *   it.
 942 *
 943 * Return:
 944 *   0 on success
 945 *   -1 fail
 946 *   %-EMSGSIZE message too big. return mtu in this case.
 947 **/
 948
 949static int ip6_tnl_xmit2(struct sk_buff *skb,
 950			 struct net_device *dev,
 951			 __u8 dsfield,
 952			 struct flowi6 *fl6,
 953			 int encap_limit,
 954			 __u32 *pmtu)
 955{
 
 956	struct ip6_tnl *t = netdev_priv(dev);
 957	struct net *net = t->net;
 958	struct net_device_stats *stats = &t->dev->stats;
 959	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 960	struct ipv6_tel_txoption opt;
 961	struct dst_entry *dst = NULL, *ndst = NULL;
 962	struct net_device *tdev;
 963	int mtu;
 964	unsigned int max_headroom = sizeof(struct ipv6hdr);
 965	u8 proto;
 966	int err = -1;
 
 967
 968	if (!fl6->flowi6_mark)
 969		dst = ip6_tnl_dst_check(t);
 970	if (!dst) {
 971		ndst = ip6_route_output(net, NULL, fl6);
 972
 973		if (ndst->error)
 974			goto tx_err_link_failure;
 975		ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
 976		if (IS_ERR(ndst)) {
 977			err = PTR_ERR(ndst);
 978			ndst = NULL;
 979			goto tx_err_link_failure;
 980		}
 981		dst = ndst;
 982	}
 983
 984	tdev = dst->dev;
 985
 986	if (tdev == dev) {
 987		stats->collisions++;
 988		net_warn_ratelimited("%s: Local routing loop detected!\n",
 989				     t->parms.name);
 
 
 990		goto tx_err_dst_release;
 991	}
 992	mtu = dst_mtu(dst) - sizeof (*ipv6h);
 993	if (encap_limit >= 0) {
 994		max_headroom += 8;
 995		mtu -= 8;
 996	}
 997	if (mtu < IPV6_MIN_MTU)
 998		mtu = IPV6_MIN_MTU;
 999	if (skb_dst(skb))
1000		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
1001	if (skb->len > mtu) {
1002		*pmtu = mtu;
1003		err = -EMSGSIZE;
1004		goto tx_err_dst_release;
1005	}
1006
1007	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1008
1009	/*
1010	 * Okay, now see if we can stuff it in the buffer as-is.
1011	 */
1012	max_headroom += LL_RESERVED_SPACE(tdev);
1013
1014	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1015	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1016		struct sk_buff *new_skb;
1017
1018		if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
1019			goto tx_err_dst_release;
1020
1021		if (skb->sk)
1022			skb_set_owner_w(new_skb, skb->sk);
1023		consume_skb(skb);
1024		skb = new_skb;
1025	}
1026	if (fl6->flowi6_mark) {
1027		skb_dst_set(skb, dst);
1028		ndst = NULL;
1029	} else {
1030		skb_dst_set_noref(skb, dst);
1031	}
1032	skb->transport_header = skb->network_header;
1033
1034	proto = fl6->flowi6_proto;
1035	if (encap_limit >= 0) {
1036		init_tel_txopt(&opt, encap_limit);
1037		ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1038	}
1039
1040	if (likely(!skb->encapsulation)) {
1041		skb_reset_inner_headers(skb);
1042		skb->encapsulation = 1;
1043	}
1044
1045	skb_push(skb, sizeof(struct ipv6hdr));
1046	skb_reset_network_header(skb);
1047	ipv6h = ipv6_hdr(skb);
1048	ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel);
 
 
1049	ipv6h->hop_limit = t->parms.hop_limit;
1050	ipv6h->nexthdr = proto;
1051	ipv6h->saddr = fl6->saddr;
1052	ipv6h->daddr = fl6->daddr;
1053	ip6tunnel_xmit(skb, dev);
1054	if (ndst)
1055		ip6_tnl_dst_store(t, ndst);
 
 
 
 
 
 
 
 
 
 
 
1056	return 0;
1057tx_err_link_failure:
1058	stats->tx_carrier_errors++;
1059	dst_link_failure(skb);
1060tx_err_dst_release:
1061	dst_release(ndst);
1062	return err;
1063}
1064
1065static inline int
1066ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1067{
1068	struct ip6_tnl *t = netdev_priv(dev);
1069	const struct iphdr  *iph = ip_hdr(skb);
1070	int encap_limit = -1;
1071	struct flowi6 fl6;
1072	__u8 dsfield;
1073	__u32 mtu;
1074	int err;
1075
1076	if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
1077	    !ip6_tnl_xmit_ctl(t))
1078		return -1;
1079
1080	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1081		encap_limit = t->parms.encap_limit;
1082
1083	memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1084	fl6.flowi6_proto = IPPROTO_IPIP;
1085
1086	dsfield = ipv4_get_dsfield(iph);
1087
1088	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1089		fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1090					  & IPV6_TCLASS_MASK;
1091	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1092		fl6.flowi6_mark = skb->mark;
1093
1094	err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1095	if (err != 0) {
1096		/* XXX: send ICMP error even if DF is not set. */
1097		if (err == -EMSGSIZE)
1098			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1099				  htonl(mtu));
1100		return -1;
1101	}
1102
1103	return 0;
1104}
1105
1106static inline int
1107ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1108{
1109	struct ip6_tnl *t = netdev_priv(dev);
1110	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1111	int encap_limit = -1;
1112	__u16 offset;
1113	struct flowi6 fl6;
1114	__u8 dsfield;
1115	__u32 mtu;
1116	int err;
1117
1118	if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
1119	    !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
1120		return -1;
1121
1122	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1123	if (offset > 0) {
1124		struct ipv6_tlv_tnl_enc_lim *tel;
1125		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1126		if (tel->encap_limit == 0) {
1127			icmpv6_send(skb, ICMPV6_PARAMPROB,
1128				    ICMPV6_HDR_FIELD, offset + 2);
1129			return -1;
1130		}
1131		encap_limit = tel->encap_limit - 1;
1132	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1133		encap_limit = t->parms.encap_limit;
1134
1135	memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1136	fl6.flowi6_proto = IPPROTO_IPV6;
1137
1138	dsfield = ipv6_get_dsfield(ipv6h);
1139	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1140		fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1141	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1142		fl6.flowlabel |= ip6_flowlabel(ipv6h);
1143	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1144		fl6.flowi6_mark = skb->mark;
1145
1146	err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1147	if (err != 0) {
1148		if (err == -EMSGSIZE)
1149			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1150		return -1;
1151	}
1152
1153	return 0;
1154}
1155
1156static netdev_tx_t
1157ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1158{
1159	struct ip6_tnl *t = netdev_priv(dev);
1160	struct net_device_stats *stats = &t->dev->stats;
1161	int ret;
1162
1163	switch (skb->protocol) {
1164	case htons(ETH_P_IP):
1165		ret = ip4ip6_tnl_xmit(skb, dev);
1166		break;
1167	case htons(ETH_P_IPV6):
1168		ret = ip6ip6_tnl_xmit(skb, dev);
1169		break;
1170	default:
1171		goto tx_err;
1172	}
1173
1174	if (ret < 0)
1175		goto tx_err;
1176
1177	return NETDEV_TX_OK;
1178
1179tx_err:
1180	stats->tx_errors++;
1181	stats->tx_dropped++;
1182	kfree_skb(skb);
1183	return NETDEV_TX_OK;
1184}
1185
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1186static void ip6_tnl_link_config(struct ip6_tnl *t)
1187{
1188	struct net_device *dev = t->dev;
1189	struct __ip6_tnl_parm *p = &t->parms;
1190	struct flowi6 *fl6 = &t->fl.u.ip6;
1191
1192	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1193	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1194
1195	/* Set up flowi template */
1196	fl6->saddr = p->laddr;
1197	fl6->daddr = p->raddr;
1198	fl6->flowi6_oif = p->link;
1199	fl6->flowlabel = 0;
1200
1201	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1202		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1203	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1204		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1205
1206	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1207	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1208
1209	if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1210		dev->flags |= IFF_POINTOPOINT;
1211	else
1212		dev->flags &= ~IFF_POINTOPOINT;
1213
1214	dev->iflink = p->link;
1215
1216	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1217		int strict = (ipv6_addr_type(&p->raddr) &
1218			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1219
1220		struct rt6_info *rt = rt6_lookup(t->net,
1221						 &p->raddr, &p->laddr,
1222						 p->link, strict);
1223
1224		if (rt == NULL)
1225			return;
1226
1227		if (rt->dst.dev) {
1228			dev->hard_header_len = rt->dst.dev->hard_header_len +
1229				sizeof (struct ipv6hdr);
1230
1231			dev->mtu = rt->dst.dev->mtu - sizeof (struct ipv6hdr);
1232			if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1233				dev->mtu-=8;
1234
1235			if (dev->mtu < IPV6_MIN_MTU)
1236				dev->mtu = IPV6_MIN_MTU;
1237		}
1238		ip6_rt_put(rt);
1239	}
1240}
1241
1242/**
1243 * ip6_tnl_change - update the tunnel parameters
1244 *   @t: tunnel to be changed
1245 *   @p: tunnel configuration parameters
1246 *
1247 * Description:
1248 *   ip6_tnl_change() updates the tunnel parameters
1249 **/
1250
1251static int
1252ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1253{
1254	t->parms.laddr = p->laddr;
1255	t->parms.raddr = p->raddr;
1256	t->parms.flags = p->flags;
1257	t->parms.hop_limit = p->hop_limit;
1258	t->parms.encap_limit = p->encap_limit;
1259	t->parms.flowinfo = p->flowinfo;
1260	t->parms.link = p->link;
1261	t->parms.proto = p->proto;
1262	ip6_tnl_dst_reset(t);
1263	ip6_tnl_link_config(t);
1264	return 0;
1265}
1266
1267static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1268{
1269	struct net *net = t->net;
1270	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1271	int err;
1272
1273	ip6_tnl_unlink(ip6n, t);
1274	synchronize_net();
1275	err = ip6_tnl_change(t, p);
1276	ip6_tnl_link(ip6n, t);
1277	netdev_state_change(t->dev);
1278	return err;
1279}
1280
1281static void
1282ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1283{
1284	p->laddr = u->laddr;
1285	p->raddr = u->raddr;
1286	p->flags = u->flags;
1287	p->hop_limit = u->hop_limit;
1288	p->encap_limit = u->encap_limit;
1289	p->flowinfo = u->flowinfo;
1290	p->link = u->link;
1291	p->proto = u->proto;
1292	memcpy(p->name, u->name, sizeof(u->name));
1293}
1294
1295static void
1296ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1297{
1298	u->laddr = p->laddr;
1299	u->raddr = p->raddr;
1300	u->flags = p->flags;
1301	u->hop_limit = p->hop_limit;
1302	u->encap_limit = p->encap_limit;
1303	u->flowinfo = p->flowinfo;
1304	u->link = p->link;
1305	u->proto = p->proto;
1306	memcpy(u->name, p->name, sizeof(u->name));
1307}
1308
1309/**
1310 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1311 *   @dev: virtual device associated with tunnel
1312 *   @ifr: parameters passed from userspace
1313 *   @cmd: command to be performed
1314 *
1315 * Description:
1316 *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1317 *   from userspace.
1318 *
1319 *   The possible commands are the following:
1320 *     %SIOCGETTUNNEL: get tunnel parameters for device
1321 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1322 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1323 *     %SIOCDELTUNNEL: delete tunnel
1324 *
1325 *   The fallback device "ip6tnl0", created during module
1326 *   initialization, can be used for creating other tunnel devices.
1327 *
1328 * Return:
1329 *   0 on success,
1330 *   %-EFAULT if unable to copy data to or from userspace,
1331 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1332 *   %-EINVAL if passed tunnel parameters are invalid,
1333 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1334 *   %-ENODEV if attempting to change or delete a nonexisting device
1335 **/
1336
1337static int
1338ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1339{
1340	int err = 0;
1341	struct ip6_tnl_parm p;
1342	struct __ip6_tnl_parm p1;
1343	struct ip6_tnl *t = netdev_priv(dev);
1344	struct net *net = t->net;
1345	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1346
1347	switch (cmd) {
1348	case SIOCGETTUNNEL:
1349		if (dev == ip6n->fb_tnl_dev) {
1350			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
1351				err = -EFAULT;
1352				break;
1353			}
1354			ip6_tnl_parm_from_user(&p1, &p);
1355			t = ip6_tnl_locate(net, &p1, 0);
1356			if (t == NULL)
1357				t = netdev_priv(dev);
1358		} else {
1359			memset(&p, 0, sizeof(p));
1360		}
1361		ip6_tnl_parm_to_user(&p, &t->parms);
 
 
1362		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
1363			err = -EFAULT;
1364		}
1365		break;
1366	case SIOCADDTUNNEL:
1367	case SIOCCHGTUNNEL:
1368		err = -EPERM;
1369		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1370			break;
1371		err = -EFAULT;
1372		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1373			break;
1374		err = -EINVAL;
1375		if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1376		    p.proto != 0)
1377			break;
1378		ip6_tnl_parm_from_user(&p1, &p);
1379		t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1380		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
1381			if (t != NULL) {
1382				if (t->dev != dev) {
1383					err = -EEXIST;
1384					break;
1385				}
1386			} else
1387				t = netdev_priv(dev);
1388
1389			err = ip6_tnl_update(t, &p1);
 
 
 
 
1390		}
1391		if (t) {
1392			err = 0;
1393			ip6_tnl_parm_to_user(&p, &t->parms);
1394			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1395				err = -EFAULT;
1396
1397		} else
1398			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1399		break;
1400	case SIOCDELTUNNEL:
1401		err = -EPERM;
1402		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1403			break;
1404
1405		if (dev == ip6n->fb_tnl_dev) {
1406			err = -EFAULT;
1407			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1408				break;
1409			err = -ENOENT;
1410			ip6_tnl_parm_from_user(&p1, &p);
1411			t = ip6_tnl_locate(net, &p1, 0);
1412			if (t == NULL)
1413				break;
1414			err = -EPERM;
1415			if (t->dev == ip6n->fb_tnl_dev)
1416				break;
1417			dev = t->dev;
1418		}
1419		err = 0;
1420		unregister_netdevice(dev);
1421		break;
1422	default:
1423		err = -EINVAL;
1424	}
1425	return err;
1426}
1427
1428/**
1429 * ip6_tnl_change_mtu - change mtu manually for tunnel device
1430 *   @dev: virtual device associated with tunnel
1431 *   @new_mtu: the new mtu
1432 *
1433 * Return:
1434 *   0 on success,
1435 *   %-EINVAL if mtu too small
1436 **/
1437
1438static int
1439ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1440{
1441	struct ip6_tnl *tnl = netdev_priv(dev);
1442
1443	if (tnl->parms.proto == IPPROTO_IPIP) {
1444		if (new_mtu < 68)
1445			return -EINVAL;
1446	} else {
1447		if (new_mtu < IPV6_MIN_MTU)
1448			return -EINVAL;
1449	}
1450	if (new_mtu > 0xFFF8 - dev->hard_header_len)
1451		return -EINVAL;
1452	dev->mtu = new_mtu;
1453	return 0;
1454}
1455
1456
1457static const struct net_device_ops ip6_tnl_netdev_ops = {
1458	.ndo_uninit	= ip6_tnl_dev_uninit,
1459	.ndo_start_xmit = ip6_tnl_xmit,
1460	.ndo_do_ioctl	= ip6_tnl_ioctl,
1461	.ndo_change_mtu = ip6_tnl_change_mtu,
1462	.ndo_get_stats	= ip6_get_stats,
1463};
1464
1465
1466/**
1467 * ip6_tnl_dev_setup - setup virtual tunnel device
1468 *   @dev: virtual device associated with tunnel
1469 *
1470 * Description:
1471 *   Initialize function pointers and device parameters
1472 **/
1473
1474static void ip6_tnl_dev_setup(struct net_device *dev)
1475{
1476	struct ip6_tnl *t;
1477
1478	dev->netdev_ops = &ip6_tnl_netdev_ops;
1479	dev->destructor = ip6_dev_free;
1480
1481	dev->type = ARPHRD_TUNNEL6;
1482	dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1483	dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1484	t = netdev_priv(dev);
1485	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1486		dev->mtu-=8;
1487	dev->flags |= IFF_NOARP;
1488	dev->addr_len = sizeof(struct in6_addr);
 
1489	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1490	/* This perm addr will be used as interface identifier by IPv6 */
1491	dev->addr_assign_type = NET_ADDR_RANDOM;
1492	eth_random_addr(dev->perm_addr);
1493}
1494
1495
1496/**
1497 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1498 *   @dev: virtual device associated with tunnel
1499 **/
1500
1501static inline int
1502ip6_tnl_dev_init_gen(struct net_device *dev)
1503{
1504	struct ip6_tnl *t = netdev_priv(dev);
1505
1506	t->dev = dev;
1507	t->net = dev_net(dev);
1508	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1509	if (!dev->tstats)
1510		return -ENOMEM;
1511	return 0;
1512}
1513
1514/**
1515 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1516 *   @dev: virtual device associated with tunnel
1517 **/
1518
1519static int ip6_tnl_dev_init(struct net_device *dev)
1520{
1521	struct ip6_tnl *t = netdev_priv(dev);
1522	int err = ip6_tnl_dev_init_gen(dev);
1523
1524	if (err)
1525		return err;
1526	ip6_tnl_link_config(t);
1527	return 0;
1528}
1529
1530/**
1531 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1532 *   @dev: fallback device
1533 *
1534 * Return: 0
1535 **/
1536
1537static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1538{
1539	struct ip6_tnl *t = netdev_priv(dev);
1540	struct net *net = dev_net(dev);
1541	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1542	int err = ip6_tnl_dev_init_gen(dev);
1543
1544	if (err)
1545		return err;
1546
1547	t->parms.proto = IPPROTO_IPV6;
1548	dev_hold(dev);
1549
1550	ip6_tnl_link_config(t);
1551
1552	rcu_assign_pointer(ip6n->tnls_wc[0], t);
1553	return 0;
1554}
1555
1556static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1557{
1558	u8 proto;
1559
1560	if (!data || !data[IFLA_IPTUN_PROTO])
1561		return 0;
1562
1563	proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1564	if (proto != IPPROTO_IPV6 &&
1565	    proto != IPPROTO_IPIP &&
1566	    proto != 0)
1567		return -EINVAL;
1568
1569	return 0;
1570}
1571
1572static void ip6_tnl_netlink_parms(struct nlattr *data[],
1573				  struct __ip6_tnl_parm *parms)
1574{
1575	memset(parms, 0, sizeof(*parms));
1576
1577	if (!data)
1578		return;
1579
1580	if (data[IFLA_IPTUN_LINK])
1581		parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1582
1583	if (data[IFLA_IPTUN_LOCAL])
1584		nla_memcpy(&parms->laddr, data[IFLA_IPTUN_LOCAL],
1585			   sizeof(struct in6_addr));
1586
1587	if (data[IFLA_IPTUN_REMOTE])
1588		nla_memcpy(&parms->raddr, data[IFLA_IPTUN_REMOTE],
1589			   sizeof(struct in6_addr));
1590
1591	if (data[IFLA_IPTUN_TTL])
1592		parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1593
1594	if (data[IFLA_IPTUN_ENCAP_LIMIT])
1595		parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1596
1597	if (data[IFLA_IPTUN_FLOWINFO])
1598		parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1599
1600	if (data[IFLA_IPTUN_FLAGS])
1601		parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1602
1603	if (data[IFLA_IPTUN_PROTO])
1604		parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1605}
1606
1607static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1608			   struct nlattr *tb[], struct nlattr *data[])
1609{
1610	struct net *net = dev_net(dev);
1611	struct ip6_tnl *nt;
1612
1613	nt = netdev_priv(dev);
1614	ip6_tnl_netlink_parms(data, &nt->parms);
1615
1616	if (ip6_tnl_locate(net, &nt->parms, 0))
1617		return -EEXIST;
1618
1619	return ip6_tnl_create2(dev);
1620}
1621
1622static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1623			      struct nlattr *data[])
1624{
1625	struct ip6_tnl *t = netdev_priv(dev);
1626	struct __ip6_tnl_parm p;
1627	struct net *net = t->net;
1628	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1629
1630	if (dev == ip6n->fb_tnl_dev)
1631		return -EINVAL;
1632
1633	ip6_tnl_netlink_parms(data, &p);
1634
1635	t = ip6_tnl_locate(net, &p, 0);
1636
1637	if (t) {
1638		if (t->dev != dev)
1639			return -EEXIST;
1640	} else
1641		t = netdev_priv(dev);
1642
1643	return ip6_tnl_update(t, &p);
1644}
1645
1646static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
1647{
1648	struct net *net = dev_net(dev);
1649	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1650
1651	if (dev != ip6n->fb_tnl_dev)
1652		unregister_netdevice_queue(dev, head);
1653}
1654
1655static size_t ip6_tnl_get_size(const struct net_device *dev)
1656{
1657	return
1658		/* IFLA_IPTUN_LINK */
1659		nla_total_size(4) +
1660		/* IFLA_IPTUN_LOCAL */
1661		nla_total_size(sizeof(struct in6_addr)) +
1662		/* IFLA_IPTUN_REMOTE */
1663		nla_total_size(sizeof(struct in6_addr)) +
1664		/* IFLA_IPTUN_TTL */
1665		nla_total_size(1) +
1666		/* IFLA_IPTUN_ENCAP_LIMIT */
1667		nla_total_size(1) +
1668		/* IFLA_IPTUN_FLOWINFO */
1669		nla_total_size(4) +
1670		/* IFLA_IPTUN_FLAGS */
1671		nla_total_size(4) +
1672		/* IFLA_IPTUN_PROTO */
1673		nla_total_size(1) +
1674		0;
1675}
1676
1677static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1678{
1679	struct ip6_tnl *tunnel = netdev_priv(dev);
1680	struct __ip6_tnl_parm *parm = &tunnel->parms;
1681
1682	if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1683	    nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr),
1684		    &parm->laddr) ||
1685	    nla_put(skb, IFLA_IPTUN_REMOTE, sizeof(struct in6_addr),
1686		    &parm->raddr) ||
1687	    nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
1688	    nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
1689	    nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
1690	    nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
1691	    nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
1692		goto nla_put_failure;
1693	return 0;
1694
1695nla_put_failure:
1696	return -EMSGSIZE;
1697}
1698
1699static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
1700	[IFLA_IPTUN_LINK]		= { .type = NLA_U32 },
1701	[IFLA_IPTUN_LOCAL]		= { .len = sizeof(struct in6_addr) },
1702	[IFLA_IPTUN_REMOTE]		= { .len = sizeof(struct in6_addr) },
1703	[IFLA_IPTUN_TTL]		= { .type = NLA_U8 },
1704	[IFLA_IPTUN_ENCAP_LIMIT]	= { .type = NLA_U8 },
1705	[IFLA_IPTUN_FLOWINFO]		= { .type = NLA_U32 },
1706	[IFLA_IPTUN_FLAGS]		= { .type = NLA_U32 },
1707	[IFLA_IPTUN_PROTO]		= { .type = NLA_U8 },
1708};
1709
1710static struct rtnl_link_ops ip6_link_ops __read_mostly = {
1711	.kind		= "ip6tnl",
1712	.maxtype	= IFLA_IPTUN_MAX,
1713	.policy		= ip6_tnl_policy,
1714	.priv_size	= sizeof(struct ip6_tnl),
1715	.setup		= ip6_tnl_dev_setup,
1716	.validate	= ip6_tnl_validate,
1717	.newlink	= ip6_tnl_newlink,
1718	.changelink	= ip6_tnl_changelink,
1719	.dellink	= ip6_tnl_dellink,
1720	.get_size	= ip6_tnl_get_size,
1721	.fill_info	= ip6_tnl_fill_info,
1722};
1723
1724static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1725	.handler	= ip4ip6_rcv,
1726	.err_handler	= ip4ip6_err,
1727	.priority	=	1,
1728};
1729
1730static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1731	.handler	= ip6ip6_rcv,
1732	.err_handler	= ip6ip6_err,
1733	.priority	=	1,
1734};
1735
1736static void __net_exit ip6_tnl_destroy_tunnels(struct net *net)
1737{
1738	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1739	struct net_device *dev, *aux;
1740	int h;
1741	struct ip6_tnl *t;
1742	LIST_HEAD(list);
1743
1744	for_each_netdev_safe(net, dev, aux)
1745		if (dev->rtnl_link_ops == &ip6_link_ops)
1746			unregister_netdevice_queue(dev, &list);
1747
1748	for (h = 0; h < HASH_SIZE; h++) {
1749		t = rtnl_dereference(ip6n->tnls_r_l[h]);
1750		while (t != NULL) {
1751			/* If dev is in the same netns, it has already
1752			 * been added to the list by the previous loop.
1753			 */
1754			if (!net_eq(dev_net(t->dev), net))
1755				unregister_netdevice_queue(t->dev, &list);
1756			t = rtnl_dereference(t->next);
1757		}
1758	}
1759
 
 
1760	unregister_netdevice_many(&list);
1761}
1762
1763static int __net_init ip6_tnl_init_net(struct net *net)
1764{
1765	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1766	struct ip6_tnl *t = NULL;
1767	int err;
1768
1769	ip6n->tnls[0] = ip6n->tnls_wc;
1770	ip6n->tnls[1] = ip6n->tnls_r_l;
1771
1772	err = -ENOMEM;
1773	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1774				      ip6_tnl_dev_setup);
1775
1776	if (!ip6n->fb_tnl_dev)
1777		goto err_alloc_dev;
1778	dev_net_set(ip6n->fb_tnl_dev, net);
1779	ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
1780	/* FB netdevice is special: we have one, and only one per netns.
1781	 * Allowing to move it to another netns is clearly unsafe.
1782	 */
1783	ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
1784
1785	err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1786	if (err < 0)
1787		goto err_register;
1788
1789	err = register_netdev(ip6n->fb_tnl_dev);
1790	if (err < 0)
1791		goto err_register;
1792
1793	t = netdev_priv(ip6n->fb_tnl_dev);
1794
1795	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1796	return 0;
1797
1798err_register:
1799	ip6_dev_free(ip6n->fb_tnl_dev);
1800err_alloc_dev:
1801	return err;
1802}
1803
1804static void __net_exit ip6_tnl_exit_net(struct net *net)
1805{
 
 
1806	rtnl_lock();
1807	ip6_tnl_destroy_tunnels(net);
1808	rtnl_unlock();
1809}
1810
1811static struct pernet_operations ip6_tnl_net_ops = {
1812	.init = ip6_tnl_init_net,
1813	.exit = ip6_tnl_exit_net,
1814	.id   = &ip6_tnl_net_id,
1815	.size = sizeof(struct ip6_tnl_net),
1816};
1817
1818/**
1819 * ip6_tunnel_init - register protocol and reserve needed resources
1820 *
1821 * Return: 0 on success
1822 **/
1823
1824static int __init ip6_tunnel_init(void)
1825{
1826	int  err;
1827
1828	err = register_pernet_device(&ip6_tnl_net_ops);
1829	if (err < 0)
1830		goto out_pernet;
1831
1832	err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1833	if (err < 0) {
1834		pr_err("%s: can't register ip4ip6\n", __func__);
1835		goto out_ip4ip6;
1836	}
1837
1838	err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1839	if (err < 0) {
1840		pr_err("%s: can't register ip6ip6\n", __func__);
1841		goto out_ip6ip6;
1842	}
1843	err = rtnl_link_register(&ip6_link_ops);
1844	if (err < 0)
1845		goto rtnl_link_failed;
1846
1847	return 0;
1848
1849rtnl_link_failed:
1850	xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1851out_ip6ip6:
1852	xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1853out_ip4ip6:
1854	unregister_pernet_device(&ip6_tnl_net_ops);
1855out_pernet:
1856	return err;
1857}
1858
1859/**
1860 * ip6_tunnel_cleanup - free resources and unregister protocol
1861 **/
1862
1863static void __exit ip6_tunnel_cleanup(void)
1864{
1865	rtnl_link_unregister(&ip6_link_ops);
1866	if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1867		pr_info("%s: can't deregister ip4ip6\n", __func__);
1868
1869	if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1870		pr_info("%s: can't deregister ip6ip6\n", __func__);
1871
1872	unregister_pernet_device(&ip6_tnl_net_ops);
1873}
1874
1875module_init(ip6_tunnel_init);
1876module_exit(ip6_tunnel_cleanup);