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v4.17
   1/*
   2 *	IPv6 virtual tunneling interface
   3 *
   4 *	Copyright (C) 2013 secunet Security Networks AG
   5 *
   6 *	Author:
   7 *	Steffen Klassert <steffen.klassert@secunet.com>
   8 *
   9 *	Based on:
  10 *	net/ipv6/ip6_tunnel.c
  11 *
  12 *	This program is free software; you can redistribute it and/or
  13 *	modify it under the terms of the GNU General Public License
  14 *	as published by the Free Software Foundation; either version
  15 *	2 of the License, or (at your option) any later version.
  16 */
  17
  18#include <linux/module.h>
  19#include <linux/capability.h>
  20#include <linux/errno.h>
  21#include <linux/types.h>
  22#include <linux/sockios.h>
  23#include <linux/icmp.h>
  24#include <linux/if.h>
  25#include <linux/in.h>
  26#include <linux/ip.h>
  27#include <linux/net.h>
  28#include <linux/in6.h>
  29#include <linux/netdevice.h>
  30#include <linux/if_arp.h>
  31#include <linux/icmpv6.h>
  32#include <linux/init.h>
  33#include <linux/route.h>
  34#include <linux/rtnetlink.h>
  35#include <linux/netfilter_ipv6.h>
  36#include <linux/slab.h>
  37#include <linux/hash.h>
  38
  39#include <linux/uaccess.h>
  40#include <linux/atomic.h>
  41
  42#include <net/icmp.h>
  43#include <net/ip.h>
  44#include <net/ip_tunnels.h>
  45#include <net/ipv6.h>
  46#include <net/ip6_route.h>
  47#include <net/addrconf.h>
  48#include <net/ip6_tunnel.h>
  49#include <net/xfrm.h>
  50#include <net/net_namespace.h>
  51#include <net/netns/generic.h>
  52#include <linux/etherdevice.h>
  53
  54#define IP6_VTI_HASH_SIZE_SHIFT  5
  55#define IP6_VTI_HASH_SIZE (1 << IP6_VTI_HASH_SIZE_SHIFT)
  56
  57static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  58{
  59	u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  60
  61	return hash_32(hash, IP6_VTI_HASH_SIZE_SHIFT);
  62}
  63
  64static int vti6_dev_init(struct net_device *dev);
  65static void vti6_dev_setup(struct net_device *dev);
  66static struct rtnl_link_ops vti6_link_ops __read_mostly;
  67
  68static unsigned int vti6_net_id __read_mostly;
  69struct vti6_net {
  70	/* the vti6 tunnel fallback device */
  71	struct net_device *fb_tnl_dev;
  72	/* lists for storing tunnels in use */
  73	struct ip6_tnl __rcu *tnls_r_l[IP6_VTI_HASH_SIZE];
  74	struct ip6_tnl __rcu *tnls_wc[1];
  75	struct ip6_tnl __rcu **tnls[2];
  76};
  77
  78#define for_each_vti6_tunnel_rcu(start) \
  79	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
  80
  81/**
  82 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses
  83 *   @net: network namespace
  84 *   @remote: the address of the tunnel exit-point
  85 *   @local: the address of the tunnel entry-point
  86 *
  87 * Return:
  88 *   tunnel matching given end-points if found,
  89 *   else fallback tunnel if its device is up,
  90 *   else %NULL
  91 **/
  92static struct ip6_tnl *
  93vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
  94		const struct in6_addr *local)
  95{
  96	unsigned int hash = HASH(remote, local);
  97	struct ip6_tnl *t;
  98	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
  99	struct in6_addr any;
 100
 101	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 102		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 103		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 104		    (t->dev->flags & IFF_UP))
 105			return t;
 106	}
 107
 108	memset(&any, 0, sizeof(any));
 109	hash = HASH(&any, local);
 110	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 111		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 112		    (t->dev->flags & IFF_UP))
 113			return t;
 114	}
 115
 116	hash = HASH(remote, &any);
 117	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 118		if (ipv6_addr_equal(remote, &t->parms.raddr) &&
 119		    (t->dev->flags & IFF_UP))
 120			return t;
 121	}
 122
 123	t = rcu_dereference(ip6n->tnls_wc[0]);
 124	if (t && (t->dev->flags & IFF_UP))
 125		return t;
 126
 127	return NULL;
 128}
 129
 130/**
 131 * vti6_tnl_bucket - get head of list matching given tunnel parameters
 132 *   @p: parameters containing tunnel end-points
 133 *
 134 * Description:
 135 *   vti6_tnl_bucket() returns the head of the list matching the
 136 *   &struct in6_addr entries laddr and raddr in @p.
 137 *
 138 * Return: head of IPv6 tunnel list
 139 **/
 140static struct ip6_tnl __rcu **
 141vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
 142{
 143	const struct in6_addr *remote = &p->raddr;
 144	const struct in6_addr *local = &p->laddr;
 145	unsigned int h = 0;
 146	int prio = 0;
 147
 148	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 149		prio = 1;
 150		h = HASH(remote, local);
 151	}
 152	return &ip6n->tnls[prio][h];
 153}
 154
 155static void
 156vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
 157{
 158	struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
 159
 160	rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 161	rcu_assign_pointer(*tp, t);
 162}
 163
 164static void
 165vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
 166{
 167	struct ip6_tnl __rcu **tp;
 168	struct ip6_tnl *iter;
 169
 170	for (tp = vti6_tnl_bucket(ip6n, &t->parms);
 171	     (iter = rtnl_dereference(*tp)) != NULL;
 172	     tp = &iter->next) {
 173		if (t == iter) {
 174			rcu_assign_pointer(*tp, t->next);
 175			break;
 176		}
 177	}
 178}
 179
 180static void vti6_dev_free(struct net_device *dev)
 181{
 182	free_percpu(dev->tstats);
 
 183}
 184
 185static int vti6_tnl_create2(struct net_device *dev)
 186{
 187	struct ip6_tnl *t = netdev_priv(dev);
 188	struct net *net = dev_net(dev);
 189	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 190	int err;
 191
 192	dev->rtnl_link_ops = &vti6_link_ops;
 
 
 
 193	err = register_netdevice(dev);
 194	if (err < 0)
 195		goto out;
 196
 197	strcpy(t->parms.name, dev->name);
 
 198
 199	dev_hold(dev);
 200	vti6_tnl_link(ip6n, t);
 201
 202	return 0;
 203
 204out:
 205	return err;
 206}
 207
 208static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 209{
 210	struct net_device *dev;
 211	struct ip6_tnl *t;
 212	char name[IFNAMSIZ];
 213	int err;
 214
 215	if (p->name[0]) {
 216		if (!dev_valid_name(p->name))
 217			goto failed;
 218		strlcpy(name, p->name, IFNAMSIZ);
 219	} else {
 220		sprintf(name, "ip6_vti%%d");
 221	}
 222
 223	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
 224	if (!dev)
 225		goto failed;
 226
 227	dev_net_set(dev, net);
 228
 229	t = netdev_priv(dev);
 230	t->parms = *p;
 231	t->net = dev_net(dev);
 232
 233	err = vti6_tnl_create2(dev);
 234	if (err < 0)
 235		goto failed_free;
 236
 237	return t;
 238
 239failed_free:
 240	free_netdev(dev);
 241failed:
 242	return NULL;
 243}
 244
 245/**
 246 * vti6_locate - find or create tunnel matching given parameters
 247 *   @net: network namespace
 248 *   @p: tunnel parameters
 249 *   @create: != 0 if allowed to create new tunnel if no match found
 250 *
 251 * Description:
 252 *   vti6_locate() first tries to locate an existing tunnel
 253 *   based on @parms. If this is unsuccessful, but @create is set a new
 254 *   tunnel device is created and registered for use.
 255 *
 256 * Return:
 257 *   matching tunnel or NULL
 258 **/
 259static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
 260				   int create)
 261{
 262	const struct in6_addr *remote = &p->raddr;
 263	const struct in6_addr *local = &p->laddr;
 264	struct ip6_tnl __rcu **tp;
 265	struct ip6_tnl *t;
 266	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 267
 268	for (tp = vti6_tnl_bucket(ip6n, p);
 269	     (t = rtnl_dereference(*tp)) != NULL;
 270	     tp = &t->next) {
 271		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 272		    ipv6_addr_equal(remote, &t->parms.raddr)) {
 273			if (create)
 274				return NULL;
 275
 276			return t;
 277		}
 278	}
 279	if (!create)
 280		return NULL;
 281	return vti6_tnl_create(net, p);
 282}
 283
 284/**
 285 * vti6_dev_uninit - tunnel device uninitializer
 286 *   @dev: the device to be destroyed
 287 *
 288 * Description:
 289 *   vti6_dev_uninit() removes tunnel from its list
 290 **/
 291static void vti6_dev_uninit(struct net_device *dev)
 292{
 293	struct ip6_tnl *t = netdev_priv(dev);
 294	struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
 
 295
 296	if (dev == ip6n->fb_tnl_dev)
 297		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 298	else
 299		vti6_tnl_unlink(ip6n, t);
 300	dev_put(dev);
 301}
 302
 303static int vti6_rcv(struct sk_buff *skb)
 304{
 305	struct ip6_tnl *t;
 306	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 307
 308	rcu_read_lock();
 309	t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
 310	if (t) {
 311		if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
 312			rcu_read_unlock();
 313			goto discard;
 314		}
 315
 316		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 317			rcu_read_unlock();
 318			return 0;
 319		}
 320
 321		if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
 322			t->dev->stats.rx_dropped++;
 323			rcu_read_unlock();
 324			goto discard;
 325		}
 326
 
 
 
 327		rcu_read_unlock();
 328
 329		return xfrm6_rcv_tnl(skb, t);
 330	}
 331	rcu_read_unlock();
 332	return -EINVAL;
 333discard:
 334	kfree_skb(skb);
 335	return 0;
 336}
 337
 338static int vti6_rcv_cb(struct sk_buff *skb, int err)
 339{
 340	unsigned short family;
 341	struct net_device *dev;
 342	struct pcpu_sw_netstats *tstats;
 343	struct xfrm_state *x;
 344	struct xfrm_mode *inner_mode;
 345	struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
 346	u32 orig_mark = skb->mark;
 347	int ret;
 348
 349	if (!t)
 350		return 1;
 351
 352	dev = t->dev;
 353
 354	if (err) {
 355		dev->stats.rx_errors++;
 356		dev->stats.rx_dropped++;
 357
 358		return 0;
 359	}
 360
 361	x = xfrm_input_state(skb);
 
 362
 363	inner_mode = x->inner_mode;
 364
 365	if (x->sel.family == AF_UNSPEC) {
 366		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 367		if (inner_mode == NULL) {
 368			XFRM_INC_STATS(dev_net(skb->dev),
 369				       LINUX_MIB_XFRMINSTATEMODEERROR);
 370			return -EINVAL;
 371		}
 372	}
 373
 374	family = inner_mode->afinfo->family;
 375
 376	skb->mark = be32_to_cpu(t->parms.i_key);
 377	ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
 378	skb->mark = orig_mark;
 379
 380	if (!ret)
 381		return -EPERM;
 382
 383	skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
 384	skb->dev = dev;
 385
 386	tstats = this_cpu_ptr(dev->tstats);
 387	u64_stats_update_begin(&tstats->syncp);
 388	tstats->rx_packets++;
 389	tstats->rx_bytes += skb->len;
 390	u64_stats_update_end(&tstats->syncp);
 391
 392	return 0;
 393}
 394
 395/**
 396 * vti6_addr_conflict - compare packet addresses to tunnel's own
 397 *   @t: the outgoing tunnel device
 398 *   @hdr: IPv6 header from the incoming packet
 399 *
 400 * Description:
 401 *   Avoid trivial tunneling loop by checking that tunnel exit-point
 402 *   doesn't match source of incoming packet.
 403 *
 404 * Return:
 405 *   1 if conflict,
 406 *   0 else
 407 **/
 408static inline bool
 409vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 410{
 411	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 412}
 413
 414static bool vti6_state_check(const struct xfrm_state *x,
 415			     const struct in6_addr *dst,
 416			     const struct in6_addr *src)
 417{
 418	xfrm_address_t *daddr = (xfrm_address_t *)dst;
 419	xfrm_address_t *saddr = (xfrm_address_t *)src;
 420
 421	/* if there is no transform then this tunnel is not functional.
 422	 * Or if the xfrm is not mode tunnel.
 423	 */
 424	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
 425	    x->props.family != AF_INET6)
 426		return false;
 427
 428	if (ipv6_addr_any(dst))
 429		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
 430
 431	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
 432		return false;
 433
 434	return true;
 435}
 436
 437/**
 438 * vti6_xmit - send a packet
 439 *   @skb: the outgoing socket buffer
 440 *   @dev: the outgoing tunnel device
 441 *   @fl: the flow informations for the xfrm_lookup
 442 **/
 443static int
 444vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 445{
 446	struct ip6_tnl *t = netdev_priv(dev);
 447	struct net_device_stats *stats = &t->dev->stats;
 448	struct dst_entry *dst = skb_dst(skb);
 449	struct net_device *tdev;
 450	struct xfrm_state *x;
 451	int pkt_len = skb->len;
 452	int err = -1;
 453	int mtu;
 454
 455	if (!dst)
 456		goto tx_err_link_failure;
 457
 458	dst_hold(dst);
 459	dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
 460	if (IS_ERR(dst)) {
 461		err = PTR_ERR(dst);
 462		dst = NULL;
 463		goto tx_err_link_failure;
 464	}
 465
 466	x = dst->xfrm;
 467	if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
 468		goto tx_err_link_failure;
 469
 470	if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
 471			      (const struct in6_addr *)&x->id.daddr))
 472		goto tx_err_link_failure;
 473
 474	tdev = dst->dev;
 475
 476	if (tdev == dev) {
 477		stats->collisions++;
 478		net_warn_ratelimited("%s: Local routing loop detected!\n",
 479				     t->parms.name);
 480		goto tx_err_dst_release;
 481	}
 482
 483	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
 484	skb_dst_set(skb, dst);
 485	skb->dev = skb_dst(skb)->dev;
 486
 487	mtu = dst_mtu(dst);
 488	if (!skb->ignore_df && skb->len > mtu) {
 489		skb_dst_update_pmtu(skb, mtu);
 490
 491		if (skb->protocol == htons(ETH_P_IPV6)) {
 492			if (mtu < IPV6_MIN_MTU)
 493				mtu = IPV6_MIN_MTU;
 494
 495			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 496		} else {
 497			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 498				  htonl(mtu));
 499		}
 500
 501		return -EMSGSIZE;
 502	}
 503
 504	err = dst_output(t->net, skb->sk, skb);
 505	if (net_xmit_eval(err) == 0) {
 506		struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
 507
 508		u64_stats_update_begin(&tstats->syncp);
 509		tstats->tx_bytes += pkt_len;
 510		tstats->tx_packets++;
 511		u64_stats_update_end(&tstats->syncp);
 512	} else {
 513		stats->tx_errors++;
 514		stats->tx_aborted_errors++;
 515	}
 516
 517	return 0;
 518tx_err_link_failure:
 519	stats->tx_carrier_errors++;
 520	dst_link_failure(skb);
 521tx_err_dst_release:
 522	dst_release(dst);
 523	return err;
 524}
 525
 526static netdev_tx_t
 527vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
 528{
 529	struct ip6_tnl *t = netdev_priv(dev);
 530	struct net_device_stats *stats = &t->dev->stats;
 531	struct ipv6hdr *ipv6h;
 532	struct flowi fl;
 533	int ret;
 534
 535	memset(&fl, 0, sizeof(fl));
 
 536
 537	switch (skb->protocol) {
 538	case htons(ETH_P_IPV6):
 539		ipv6h = ipv6_hdr(skb);
 540
 541		if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
 542		    vti6_addr_conflict(t, ipv6h))
 543			goto tx_err;
 544
 545		xfrm_decode_session(skb, &fl, AF_INET6);
 546		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
 547		break;
 548	case htons(ETH_P_IP):
 549		xfrm_decode_session(skb, &fl, AF_INET);
 550		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 551		break;
 552	default:
 553		goto tx_err;
 554	}
 555
 556	/* override mark with tunnel output key */
 557	fl.flowi_mark = be32_to_cpu(t->parms.o_key);
 558
 559	ret = vti6_xmit(skb, dev, &fl);
 560	if (ret < 0)
 561		goto tx_err;
 562
 563	return NETDEV_TX_OK;
 564
 565tx_err:
 566	stats->tx_errors++;
 567	stats->tx_dropped++;
 568	kfree_skb(skb);
 569	return NETDEV_TX_OK;
 570}
 571
 572static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 573		    u8 type, u8 code, int offset, __be32 info)
 574{
 575	__be32 spi;
 576	__u32 mark;
 577	struct xfrm_state *x;
 578	struct ip6_tnl *t;
 579	struct ip_esp_hdr *esph;
 580	struct ip_auth_hdr *ah;
 581	struct ip_comp_hdr *ipch;
 582	struct net *net = dev_net(skb->dev);
 583	const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
 584	int protocol = iph->nexthdr;
 585
 586	t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
 587	if (!t)
 588		return -1;
 589
 590	mark = be32_to_cpu(t->parms.o_key);
 591
 592	switch (protocol) {
 593	case IPPROTO_ESP:
 594		esph = (struct ip_esp_hdr *)(skb->data + offset);
 595		spi = esph->spi;
 596		break;
 597	case IPPROTO_AH:
 598		ah = (struct ip_auth_hdr *)(skb->data + offset);
 599		spi = ah->spi;
 600		break;
 601	case IPPROTO_COMP:
 602		ipch = (struct ip_comp_hdr *)(skb->data + offset);
 603		spi = htonl(ntohs(ipch->cpi));
 604		break;
 605	default:
 606		return 0;
 607	}
 608
 609	if (type != ICMPV6_PKT_TOOBIG &&
 610	    type != NDISC_REDIRECT)
 611		return 0;
 612
 613	x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
 614			      spi, protocol, AF_INET6);
 615	if (!x)
 616		return 0;
 617
 618	if (type == NDISC_REDIRECT)
 619		ip6_redirect(skb, net, skb->dev->ifindex, 0,
 620			     sock_net_uid(net, NULL));
 621	else
 622		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
 623	xfrm_state_put(x);
 624
 625	return 0;
 626}
 627
 628static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu)
 629{
 630	struct net_device *dev = t->dev;
 631	struct __ip6_tnl_parm *p = &t->parms;
 632	struct net_device *tdev = NULL;
 633	int mtu;
 634
 635	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
 636	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
 637
 638	p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
 639		      IP6_TNL_F_CAP_PER_PACKET);
 640	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
 641
 642	if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
 643		dev->flags |= IFF_POINTOPOINT;
 644	else
 645		dev->flags &= ~IFF_POINTOPOINT;
 646
 647	if (keep_mtu && dev->mtu) {
 648		dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu);
 649		return;
 650	}
 651
 652	if (p->flags & IP6_TNL_F_CAP_XMIT) {
 653		int strict = (ipv6_addr_type(&p->raddr) &
 654			      (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
 655		struct rt6_info *rt = rt6_lookup(t->net,
 656						 &p->raddr, &p->laddr,
 657						 p->link, NULL, strict);
 658
 659		if (rt)
 660			tdev = rt->dst.dev;
 661		ip6_rt_put(rt);
 662	}
 663
 664	if (!tdev && p->link)
 665		tdev = __dev_get_by_index(t->net, p->link);
 666
 667	if (tdev)
 668		mtu = tdev->mtu - sizeof(struct ipv6hdr);
 669	else
 670		mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr);
 671
 672	dev->mtu = max_t(int, mtu, IPV4_MIN_MTU);
 673}
 674
 675/**
 676 * vti6_tnl_change - update the tunnel parameters
 677 *   @t: tunnel to be changed
 678 *   @p: tunnel configuration parameters
 679 *   @keep_mtu: MTU was set from userspace, don't re-compute it
 680 *
 681 * Description:
 682 *   vti6_tnl_change() updates the tunnel parameters
 683 **/
 684static int
 685vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
 686		bool keep_mtu)
 687{
 688	t->parms.laddr = p->laddr;
 689	t->parms.raddr = p->raddr;
 690	t->parms.link = p->link;
 691	t->parms.i_key = p->i_key;
 692	t->parms.o_key = p->o_key;
 693	t->parms.proto = p->proto;
 694	t->parms.fwmark = p->fwmark;
 695	dst_cache_reset(&t->dst_cache);
 696	vti6_link_config(t, keep_mtu);
 697	return 0;
 698}
 699
 700static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p,
 701		       bool keep_mtu)
 702{
 703	struct net *net = dev_net(t->dev);
 704	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 705	int err;
 706
 707	vti6_tnl_unlink(ip6n, t);
 708	synchronize_net();
 709	err = vti6_tnl_change(t, p, keep_mtu);
 710	vti6_tnl_link(ip6n, t);
 711	netdev_state_change(t->dev);
 712	return err;
 713}
 714
 715static void
 716vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
 717{
 718	p->laddr = u->laddr;
 719	p->raddr = u->raddr;
 720	p->link = u->link;
 721	p->i_key = u->i_key;
 722	p->o_key = u->o_key;
 723	p->proto = u->proto;
 724
 725	memcpy(p->name, u->name, sizeof(u->name));
 726}
 727
 728static void
 729vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
 730{
 731	u->laddr = p->laddr;
 732	u->raddr = p->raddr;
 733	u->link = p->link;
 734	u->i_key = p->i_key;
 735	u->o_key = p->o_key;
 736	if (u->i_key)
 737		u->i_flags |= GRE_KEY;
 738	if (u->o_key)
 739		u->o_flags |= GRE_KEY;
 740	u->proto = p->proto;
 741
 742	memcpy(u->name, p->name, sizeof(u->name));
 743}
 744
 745/**
 746 * vti6_tnl_ioctl - configure vti6 tunnels from userspace
 747 *   @dev: virtual device associated with tunnel
 748 *   @ifr: parameters passed from userspace
 749 *   @cmd: command to be performed
 750 *
 751 * Description:
 752 *   vti6_ioctl() is used for managing vti6 tunnels
 753 *   from userspace.
 754 *
 755 *   The possible commands are the following:
 756 *     %SIOCGETTUNNEL: get tunnel parameters for device
 757 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
 758 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
 759 *     %SIOCDELTUNNEL: delete tunnel
 760 *
 761 *   The fallback device "ip6_vti0", created during module
 762 *   initialization, can be used for creating other tunnel devices.
 763 *
 764 * Return:
 765 *   0 on success,
 766 *   %-EFAULT if unable to copy data to or from userspace,
 767 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
 768 *   %-EINVAL if passed tunnel parameters are invalid,
 769 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
 770 *   %-ENODEV if attempting to change or delete a nonexisting device
 771 **/
 772static int
 773vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 774{
 775	int err = 0;
 776	struct ip6_tnl_parm2 p;
 777	struct __ip6_tnl_parm p1;
 778	struct ip6_tnl *t = NULL;
 779	struct net *net = dev_net(dev);
 780	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 781
 782	switch (cmd) {
 783	case SIOCGETTUNNEL:
 784		if (dev == ip6n->fb_tnl_dev) {
 785			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
 786				err = -EFAULT;
 787				break;
 788			}
 789			vti6_parm_from_user(&p1, &p);
 790			t = vti6_locate(net, &p1, 0);
 791		} else {
 792			memset(&p, 0, sizeof(p));
 793		}
 794		if (!t)
 795			t = netdev_priv(dev);
 796		vti6_parm_to_user(&p, &t->parms);
 797		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 798			err = -EFAULT;
 799		break;
 800	case SIOCADDTUNNEL:
 801	case SIOCCHGTUNNEL:
 802		err = -EPERM;
 803		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 804			break;
 805		err = -EFAULT;
 806		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 807			break;
 808		err = -EINVAL;
 809		if (p.proto != IPPROTO_IPV6  && p.proto != 0)
 810			break;
 811		vti6_parm_from_user(&p1, &p);
 812		t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
 813		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
 814			if (t) {
 815				if (t->dev != dev) {
 816					err = -EEXIST;
 817					break;
 818				}
 819			} else
 820				t = netdev_priv(dev);
 821
 822			err = vti6_update(t, &p1, false);
 823		}
 824		if (t) {
 825			err = 0;
 826			vti6_parm_to_user(&p, &t->parms);
 827			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 828				err = -EFAULT;
 829
 830		} else
 831			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
 832		break;
 833	case SIOCDELTUNNEL:
 834		err = -EPERM;
 835		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 836			break;
 837
 838		if (dev == ip6n->fb_tnl_dev) {
 839			err = -EFAULT;
 840			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 841				break;
 842			err = -ENOENT;
 843			vti6_parm_from_user(&p1, &p);
 844			t = vti6_locate(net, &p1, 0);
 845			if (!t)
 846				break;
 847			err = -EPERM;
 848			if (t->dev == ip6n->fb_tnl_dev)
 849				break;
 850			dev = t->dev;
 851		}
 852		err = 0;
 853		unregister_netdevice(dev);
 854		break;
 855	default:
 856		err = -EINVAL;
 857	}
 858	return err;
 859}
 860
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 861static const struct net_device_ops vti6_netdev_ops = {
 862	.ndo_init	= vti6_dev_init,
 863	.ndo_uninit	= vti6_dev_uninit,
 864	.ndo_start_xmit = vti6_tnl_xmit,
 865	.ndo_do_ioctl	= vti6_ioctl,
 
 866	.ndo_get_stats64 = ip_tunnel_get_stats64,
 867	.ndo_get_iflink = ip6_tnl_get_iflink,
 868};
 869
 870/**
 871 * vti6_dev_setup - setup virtual tunnel device
 872 *   @dev: virtual device associated with tunnel
 873 *
 874 * Description:
 875 *   Initialize function pointers and device parameters
 876 **/
 877static void vti6_dev_setup(struct net_device *dev)
 878{
 
 
 879	dev->netdev_ops = &vti6_netdev_ops;
 880	dev->needs_free_netdev = true;
 881	dev->priv_destructor = vti6_dev_free;
 882
 883	dev->type = ARPHRD_TUNNEL6;
 884	dev->min_mtu = IPV4_MIN_MTU;
 885	dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr);
 
 886	dev->flags |= IFF_NOARP;
 887	dev->addr_len = sizeof(struct in6_addr);
 888	netif_keep_dst(dev);
 889	/* This perm addr will be used as interface identifier by IPv6 */
 890	dev->addr_assign_type = NET_ADDR_RANDOM;
 891	eth_random_addr(dev->perm_addr);
 892}
 893
 894/**
 895 * vti6_dev_init_gen - general initializer for all tunnel devices
 896 *   @dev: virtual device associated with tunnel
 897 **/
 898static inline int vti6_dev_init_gen(struct net_device *dev)
 899{
 900	struct ip6_tnl *t = netdev_priv(dev);
 901
 902	t->dev = dev;
 903	t->net = dev_net(dev);
 904	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 905	if (!dev->tstats)
 906		return -ENOMEM;
 907	return 0;
 908}
 909
 910/**
 911 * vti6_dev_init - initializer for all non fallback tunnel devices
 912 *   @dev: virtual device associated with tunnel
 913 **/
 914static int vti6_dev_init(struct net_device *dev)
 915{
 916	struct ip6_tnl *t = netdev_priv(dev);
 917	int err = vti6_dev_init_gen(dev);
 918
 919	if (err)
 920		return err;
 921	vti6_link_config(t, true);
 922	return 0;
 923}
 924
 925/**
 926 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
 927 *   @dev: fallback device
 928 *
 929 * Return: 0
 930 **/
 931static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
 932{
 933	struct ip6_tnl *t = netdev_priv(dev);
 934	struct net *net = dev_net(dev);
 935	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 
 
 
 
 936
 937	t->parms.proto = IPPROTO_IPV6;
 938	dev_hold(dev);
 939
 
 
 940	rcu_assign_pointer(ip6n->tnls_wc[0], t);
 941	return 0;
 942}
 943
 944static int vti6_validate(struct nlattr *tb[], struct nlattr *data[],
 945			 struct netlink_ext_ack *extack)
 946{
 947	return 0;
 948}
 949
 950static void vti6_netlink_parms(struct nlattr *data[],
 951			       struct __ip6_tnl_parm *parms)
 952{
 953	memset(parms, 0, sizeof(*parms));
 954
 955	if (!data)
 956		return;
 957
 958	if (data[IFLA_VTI_LINK])
 959		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
 960
 961	if (data[IFLA_VTI_LOCAL])
 962		parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
 
 963
 964	if (data[IFLA_VTI_REMOTE])
 965		parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
 
 966
 967	if (data[IFLA_VTI_IKEY])
 968		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
 969
 970	if (data[IFLA_VTI_OKEY])
 971		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
 972
 973	if (data[IFLA_VTI_FWMARK])
 974		parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
 975}
 976
 977static int vti6_newlink(struct net *src_net, struct net_device *dev,
 978			struct nlattr *tb[], struct nlattr *data[],
 979			struct netlink_ext_ack *extack)
 980{
 981	struct net *net = dev_net(dev);
 982	struct ip6_tnl *nt;
 983
 984	nt = netdev_priv(dev);
 985	vti6_netlink_parms(data, &nt->parms);
 986
 987	nt->parms.proto = IPPROTO_IPV6;
 988
 989	if (vti6_locate(net, &nt->parms, 0))
 990		return -EEXIST;
 991
 992	return vti6_tnl_create2(dev);
 993}
 994
 995static void vti6_dellink(struct net_device *dev, struct list_head *head)
 996{
 997	struct net *net = dev_net(dev);
 998	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 999
1000	if (dev != ip6n->fb_tnl_dev)
1001		unregister_netdevice_queue(dev, head);
1002}
1003
1004static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
1005			   struct nlattr *data[],
1006			   struct netlink_ext_ack *extack)
1007{
1008	struct ip6_tnl *t;
1009	struct __ip6_tnl_parm p;
1010	struct net *net = dev_net(dev);
1011	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1012
1013	if (dev == ip6n->fb_tnl_dev)
1014		return -EINVAL;
1015
1016	vti6_netlink_parms(data, &p);
1017
1018	t = vti6_locate(net, &p, 0);
1019
1020	if (t) {
1021		if (t->dev != dev)
1022			return -EEXIST;
1023	} else
1024		t = netdev_priv(dev);
1025
1026	return vti6_update(t, &p, tb && tb[IFLA_MTU]);
1027}
1028
1029static size_t vti6_get_size(const struct net_device *dev)
1030{
1031	return
1032		/* IFLA_VTI_LINK */
1033		nla_total_size(4) +
1034		/* IFLA_VTI_LOCAL */
1035		nla_total_size(sizeof(struct in6_addr)) +
1036		/* IFLA_VTI_REMOTE */
1037		nla_total_size(sizeof(struct in6_addr)) +
1038		/* IFLA_VTI_IKEY */
1039		nla_total_size(4) +
1040		/* IFLA_VTI_OKEY */
1041		nla_total_size(4) +
1042		/* IFLA_VTI_FWMARK */
1043		nla_total_size(4) +
1044		0;
1045}
1046
1047static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1048{
1049	struct ip6_tnl *tunnel = netdev_priv(dev);
1050	struct __ip6_tnl_parm *parm = &tunnel->parms;
1051
1052	if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
1053	    nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
1054	    nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
 
 
1055	    nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
1056	    nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key) ||
1057	    nla_put_u32(skb, IFLA_VTI_FWMARK, parm->fwmark))
1058		goto nla_put_failure;
1059	return 0;
1060
1061nla_put_failure:
1062	return -EMSGSIZE;
1063}
1064
1065static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
1066	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
1067	[IFLA_VTI_LOCAL]	= { .len = sizeof(struct in6_addr) },
1068	[IFLA_VTI_REMOTE]	= { .len = sizeof(struct in6_addr) },
1069	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
1070	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
1071	[IFLA_VTI_FWMARK]	= { .type = NLA_U32 },
1072};
1073
1074static struct rtnl_link_ops vti6_link_ops __read_mostly = {
1075	.kind		= "vti6",
1076	.maxtype	= IFLA_VTI_MAX,
1077	.policy		= vti6_policy,
1078	.priv_size	= sizeof(struct ip6_tnl),
1079	.setup		= vti6_dev_setup,
1080	.validate	= vti6_validate,
1081	.newlink	= vti6_newlink,
1082	.dellink	= vti6_dellink,
1083	.changelink	= vti6_changelink,
1084	.get_size	= vti6_get_size,
1085	.fill_info	= vti6_fill_info,
1086	.get_link_net	= ip6_tnl_get_link_net,
1087};
1088
1089static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n,
1090					    struct list_head *list)
1091{
1092	int h;
1093	struct ip6_tnl *t;
 
1094
1095	for (h = 0; h < IP6_VTI_HASH_SIZE; h++) {
1096		t = rtnl_dereference(ip6n->tnls_r_l[h]);
1097		while (t) {
1098			unregister_netdevice_queue(t->dev, list);
1099			t = rtnl_dereference(t->next);
1100		}
1101	}
1102
1103	t = rtnl_dereference(ip6n->tnls_wc[0]);
1104	unregister_netdevice_queue(t->dev, list);
 
1105}
1106
1107static int __net_init vti6_init_net(struct net *net)
1108{
1109	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1110	struct ip6_tnl *t = NULL;
1111	int err;
1112
1113	ip6n->tnls[0] = ip6n->tnls_wc;
1114	ip6n->tnls[1] = ip6n->tnls_r_l;
1115
1116	err = -ENOMEM;
1117	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1118					NET_NAME_UNKNOWN, vti6_dev_setup);
1119
1120	if (!ip6n->fb_tnl_dev)
1121		goto err_alloc_dev;
1122	dev_net_set(ip6n->fb_tnl_dev, net);
1123	ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
1124
1125	err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1126	if (err < 0)
1127		goto err_register;
1128
1129	err = register_netdev(ip6n->fb_tnl_dev);
1130	if (err < 0)
1131		goto err_register;
1132
1133	t = netdev_priv(ip6n->fb_tnl_dev);
1134
1135	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1136	return 0;
1137
1138err_register:
1139	free_netdev(ip6n->fb_tnl_dev);
1140err_alloc_dev:
1141	return err;
1142}
1143
1144static void __net_exit vti6_exit_batch_net(struct list_head *net_list)
1145{
1146	struct vti6_net *ip6n;
1147	struct net *net;
1148	LIST_HEAD(list);
1149
1150	rtnl_lock();
1151	list_for_each_entry(net, net_list, exit_list) {
1152		ip6n = net_generic(net, vti6_net_id);
1153		vti6_destroy_tunnels(ip6n, &list);
1154	}
1155	unregister_netdevice_many(&list);
1156	rtnl_unlock();
1157}
1158
1159static struct pernet_operations vti6_net_ops = {
1160	.init = vti6_init_net,
1161	.exit_batch = vti6_exit_batch_net,
1162	.id   = &vti6_net_id,
1163	.size = sizeof(struct vti6_net),
1164};
1165
1166static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1167	.handler	=	vti6_rcv,
1168	.cb_handler	=	vti6_rcv_cb,
1169	.err_handler	=	vti6_err,
1170	.priority	=	100,
1171};
1172
1173static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1174	.handler	=	vti6_rcv,
1175	.cb_handler	=	vti6_rcv_cb,
1176	.err_handler	=	vti6_err,
1177	.priority	=	100,
1178};
1179
1180static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1181	.handler	=	vti6_rcv,
1182	.cb_handler	=	vti6_rcv_cb,
1183	.err_handler	=	vti6_err,
1184	.priority	=	100,
1185};
1186
1187/**
1188 * vti6_tunnel_init - register protocol and reserve needed resources
1189 *
1190 * Return: 0 on success
1191 **/
1192static int __init vti6_tunnel_init(void)
1193{
1194	const char *msg;
1195	int err;
1196
1197	msg = "tunnel device";
1198	err = register_pernet_device(&vti6_net_ops);
1199	if (err < 0)
1200		goto pernet_dev_failed;
1201
1202	msg = "tunnel protocols";
1203	err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1204	if (err < 0)
1205		goto xfrm_proto_esp_failed;
 
 
 
 
1206	err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1207	if (err < 0)
1208		goto xfrm_proto_ah_failed;
 
 
 
 
 
1209	err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1210	if (err < 0)
1211		goto xfrm_proto_comp_failed;
 
 
 
 
 
1212
1213	msg = "netlink interface";
1214	err = rtnl_link_register(&vti6_link_ops);
1215	if (err < 0)
1216		goto rtnl_link_failed;
1217
1218	return 0;
1219
1220rtnl_link_failed:
1221	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1222xfrm_proto_comp_failed:
1223	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1224xfrm_proto_ah_failed:
1225	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1226xfrm_proto_esp_failed:
1227	unregister_pernet_device(&vti6_net_ops);
1228pernet_dev_failed:
1229	pr_err("vti6 init: failed to register %s\n", msg);
1230	return err;
1231}
1232
1233/**
1234 * vti6_tunnel_cleanup - free resources and unregister protocol
1235 **/
1236static void __exit vti6_tunnel_cleanup(void)
1237{
1238	rtnl_link_unregister(&vti6_link_ops);
1239	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1240	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1241	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
 
 
 
 
1242	unregister_pernet_device(&vti6_net_ops);
1243}
1244
1245module_init(vti6_tunnel_init);
1246module_exit(vti6_tunnel_cleanup);
1247MODULE_LICENSE("GPL");
1248MODULE_ALIAS_RTNL_LINK("vti6");
1249MODULE_ALIAS_NETDEV("ip6_vti0");
1250MODULE_AUTHOR("Steffen Klassert");
1251MODULE_DESCRIPTION("IPv6 virtual tunnel interface");
v3.15
   1/*
   2 *	IPv6 virtual tunneling interface
   3 *
   4 *	Copyright (C) 2013 secunet Security Networks AG
   5 *
   6 *	Author:
   7 *	Steffen Klassert <steffen.klassert@secunet.com>
   8 *
   9 *	Based on:
  10 *	net/ipv6/ip6_tunnel.c
  11 *
  12 *	This program is free software; you can redistribute it and/or
  13 *	modify it under the terms of the GNU General Public License
  14 *	as published by the Free Software Foundation; either version
  15 *	2 of the License, or (at your option) any later version.
  16 */
  17
  18#include <linux/module.h>
  19#include <linux/capability.h>
  20#include <linux/errno.h>
  21#include <linux/types.h>
  22#include <linux/sockios.h>
  23#include <linux/icmp.h>
  24#include <linux/if.h>
  25#include <linux/in.h>
  26#include <linux/ip.h>
  27#include <linux/net.h>
  28#include <linux/in6.h>
  29#include <linux/netdevice.h>
  30#include <linux/if_arp.h>
  31#include <linux/icmpv6.h>
  32#include <linux/init.h>
  33#include <linux/route.h>
  34#include <linux/rtnetlink.h>
  35#include <linux/netfilter_ipv6.h>
  36#include <linux/slab.h>
  37#include <linux/hash.h>
  38
  39#include <linux/uaccess.h>
  40#include <linux/atomic.h>
  41
  42#include <net/icmp.h>
  43#include <net/ip.h>
  44#include <net/ip_tunnels.h>
  45#include <net/ipv6.h>
  46#include <net/ip6_route.h>
  47#include <net/addrconf.h>
  48#include <net/ip6_tunnel.h>
  49#include <net/xfrm.h>
  50#include <net/net_namespace.h>
  51#include <net/netns/generic.h>
 
  52
  53#define HASH_SIZE_SHIFT  5
  54#define HASH_SIZE (1 << HASH_SIZE_SHIFT)
  55
  56static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  57{
  58	u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  59
  60	return hash_32(hash, HASH_SIZE_SHIFT);
  61}
  62
  63static int vti6_dev_init(struct net_device *dev);
  64static void vti6_dev_setup(struct net_device *dev);
  65static struct rtnl_link_ops vti6_link_ops __read_mostly;
  66
  67static int vti6_net_id __read_mostly;
  68struct vti6_net {
  69	/* the vti6 tunnel fallback device */
  70	struct net_device *fb_tnl_dev;
  71	/* lists for storing tunnels in use */
  72	struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
  73	struct ip6_tnl __rcu *tnls_wc[1];
  74	struct ip6_tnl __rcu **tnls[2];
  75};
  76
  77#define for_each_vti6_tunnel_rcu(start) \
  78	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
  79
  80/**
  81 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses
  82 *   @net: network namespace
  83 *   @remote: the address of the tunnel exit-point
  84 *   @local: the address of the tunnel entry-point
  85 *
  86 * Return:
  87 *   tunnel matching given end-points if found,
  88 *   else fallback tunnel if its device is up,
  89 *   else %NULL
  90 **/
  91static struct ip6_tnl *
  92vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
  93		const struct in6_addr *local)
  94{
  95	unsigned int hash = HASH(remote, local);
  96	struct ip6_tnl *t;
  97	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 
  98
  99	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 100		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 101		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 102		    (t->dev->flags & IFF_UP))
 103			return t;
 104	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 105	t = rcu_dereference(ip6n->tnls_wc[0]);
 106	if (t && (t->dev->flags & IFF_UP))
 107		return t;
 108
 109	return NULL;
 110}
 111
 112/**
 113 * vti6_tnl_bucket - get head of list matching given tunnel parameters
 114 *   @p: parameters containing tunnel end-points
 115 *
 116 * Description:
 117 *   vti6_tnl_bucket() returns the head of the list matching the
 118 *   &struct in6_addr entries laddr and raddr in @p.
 119 *
 120 * Return: head of IPv6 tunnel list
 121 **/
 122static struct ip6_tnl __rcu **
 123vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
 124{
 125	const struct in6_addr *remote = &p->raddr;
 126	const struct in6_addr *local = &p->laddr;
 127	unsigned int h = 0;
 128	int prio = 0;
 129
 130	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 131		prio = 1;
 132		h = HASH(remote, local);
 133	}
 134	return &ip6n->tnls[prio][h];
 135}
 136
 137static void
 138vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
 139{
 140	struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
 141
 142	rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 143	rcu_assign_pointer(*tp, t);
 144}
 145
 146static void
 147vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
 148{
 149	struct ip6_tnl __rcu **tp;
 150	struct ip6_tnl *iter;
 151
 152	for (tp = vti6_tnl_bucket(ip6n, &t->parms);
 153	     (iter = rtnl_dereference(*tp)) != NULL;
 154	     tp = &iter->next) {
 155		if (t == iter) {
 156			rcu_assign_pointer(*tp, t->next);
 157			break;
 158		}
 159	}
 160}
 161
 162static void vti6_dev_free(struct net_device *dev)
 163{
 164	free_percpu(dev->tstats);
 165	free_netdev(dev);
 166}
 167
 168static int vti6_tnl_create2(struct net_device *dev)
 169{
 170	struct ip6_tnl *t = netdev_priv(dev);
 171	struct net *net = dev_net(dev);
 172	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 173	int err;
 174
 175	err = vti6_dev_init(dev);
 176	if (err < 0)
 177		goto out;
 178
 179	err = register_netdevice(dev);
 180	if (err < 0)
 181		goto out;
 182
 183	strcpy(t->parms.name, dev->name);
 184	dev->rtnl_link_ops = &vti6_link_ops;
 185
 186	dev_hold(dev);
 187	vti6_tnl_link(ip6n, t);
 188
 189	return 0;
 190
 191out:
 192	return err;
 193}
 194
 195static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 196{
 197	struct net_device *dev;
 198	struct ip6_tnl *t;
 199	char name[IFNAMSIZ];
 200	int err;
 201
 202	if (p->name[0])
 
 
 203		strlcpy(name, p->name, IFNAMSIZ);
 204	else
 205		sprintf(name, "ip6_vti%%d");
 
 206
 207	dev = alloc_netdev(sizeof(*t), name, vti6_dev_setup);
 208	if (dev == NULL)
 209		goto failed;
 210
 211	dev_net_set(dev, net);
 212
 213	t = netdev_priv(dev);
 214	t->parms = *p;
 215	t->net = dev_net(dev);
 216
 217	err = vti6_tnl_create2(dev);
 218	if (err < 0)
 219		goto failed_free;
 220
 221	return t;
 222
 223failed_free:
 224	vti6_dev_free(dev);
 225failed:
 226	return NULL;
 227}
 228
 229/**
 230 * vti6_locate - find or create tunnel matching given parameters
 231 *   @net: network namespace
 232 *   @p: tunnel parameters
 233 *   @create: != 0 if allowed to create new tunnel if no match found
 234 *
 235 * Description:
 236 *   vti6_locate() first tries to locate an existing tunnel
 237 *   based on @parms. If this is unsuccessful, but @create is set a new
 238 *   tunnel device is created and registered for use.
 239 *
 240 * Return:
 241 *   matching tunnel or NULL
 242 **/
 243static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
 244				   int create)
 245{
 246	const struct in6_addr *remote = &p->raddr;
 247	const struct in6_addr *local = &p->laddr;
 248	struct ip6_tnl __rcu **tp;
 249	struct ip6_tnl *t;
 250	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 251
 252	for (tp = vti6_tnl_bucket(ip6n, p);
 253	     (t = rtnl_dereference(*tp)) != NULL;
 254	     tp = &t->next) {
 255		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 256		    ipv6_addr_equal(remote, &t->parms.raddr))
 
 
 
 257			return t;
 
 258	}
 259	if (!create)
 260		return NULL;
 261	return vti6_tnl_create(net, p);
 262}
 263
 264/**
 265 * vti6_dev_uninit - tunnel device uninitializer
 266 *   @dev: the device to be destroyed
 267 *
 268 * Description:
 269 *   vti6_dev_uninit() removes tunnel from its list
 270 **/
 271static void vti6_dev_uninit(struct net_device *dev)
 272{
 273	struct ip6_tnl *t = netdev_priv(dev);
 274	struct net *net = dev_net(dev);
 275	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 276
 277	if (dev == ip6n->fb_tnl_dev)
 278		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 279	else
 280		vti6_tnl_unlink(ip6n, t);
 281	dev_put(dev);
 282}
 283
 284static int vti6_rcv(struct sk_buff *skb)
 285{
 286	struct ip6_tnl *t;
 287	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 288
 289	rcu_read_lock();
 290	if ((t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
 291				 &ipv6h->daddr)) != NULL) {
 292		if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
 293			rcu_read_unlock();
 294			goto discard;
 295		}
 296
 297		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 298			rcu_read_unlock();
 299			return 0;
 300		}
 301
 302		if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
 303			t->dev->stats.rx_dropped++;
 304			rcu_read_unlock();
 305			goto discard;
 306		}
 307
 308		XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
 309		skb->mark = be32_to_cpu(t->parms.i_key);
 310
 311		rcu_read_unlock();
 312
 313		return xfrm6_rcv(skb);
 314	}
 315	rcu_read_unlock();
 316	return -EINVAL;
 317discard:
 318	kfree_skb(skb);
 319	return 0;
 320}
 321
 322static int vti6_rcv_cb(struct sk_buff *skb, int err)
 323{
 324	unsigned short family;
 325	struct net_device *dev;
 326	struct pcpu_sw_netstats *tstats;
 327	struct xfrm_state *x;
 
 328	struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
 
 
 329
 330	if (!t)
 331		return 1;
 332
 333	dev = t->dev;
 334
 335	if (err) {
 336		dev->stats.rx_errors++;
 337		dev->stats.rx_dropped++;
 338
 339		return 0;
 340	}
 341
 342	x = xfrm_input_state(skb);
 343	family = x->inner_mode->afinfo->family;
 344
 345	if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 346		return -EPERM;
 347
 348	skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
 349	skb->dev = dev;
 350
 351	tstats = this_cpu_ptr(dev->tstats);
 352	u64_stats_update_begin(&tstats->syncp);
 353	tstats->rx_packets++;
 354	tstats->rx_bytes += skb->len;
 355	u64_stats_update_end(&tstats->syncp);
 356
 357	return 0;
 358}
 359
 360/**
 361 * vti6_addr_conflict - compare packet addresses to tunnel's own
 362 *   @t: the outgoing tunnel device
 363 *   @hdr: IPv6 header from the incoming packet
 364 *
 365 * Description:
 366 *   Avoid trivial tunneling loop by checking that tunnel exit-point
 367 *   doesn't match source of incoming packet.
 368 *
 369 * Return:
 370 *   1 if conflict,
 371 *   0 else
 372 **/
 373static inline bool
 374vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 375{
 376	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 377}
 378
 379static bool vti6_state_check(const struct xfrm_state *x,
 380			     const struct in6_addr *dst,
 381			     const struct in6_addr *src)
 382{
 383	xfrm_address_t *daddr = (xfrm_address_t *)dst;
 384	xfrm_address_t *saddr = (xfrm_address_t *)src;
 385
 386	/* if there is no transform then this tunnel is not functional.
 387	 * Or if the xfrm is not mode tunnel.
 388	 */
 389	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
 390	    x->props.family != AF_INET6)
 391		return false;
 392
 393	if (ipv6_addr_any(dst))
 394		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
 395
 396	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
 397		return false;
 398
 399	return true;
 400}
 401
 402/**
 403 * vti6_xmit - send a packet
 404 *   @skb: the outgoing socket buffer
 405 *   @dev: the outgoing tunnel device
 406 *   @fl: the flow informations for the xfrm_lookup
 407 **/
 408static int
 409vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 410{
 411	struct ip6_tnl *t = netdev_priv(dev);
 412	struct net_device_stats *stats = &t->dev->stats;
 413	struct dst_entry *dst = skb_dst(skb);
 414	struct net_device *tdev;
 
 
 415	int err = -1;
 
 416
 417	if (!dst)
 418		goto tx_err_link_failure;
 419
 420	dst_hold(dst);
 421	dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
 422	if (IS_ERR(dst)) {
 423		err = PTR_ERR(dst);
 424		dst = NULL;
 425		goto tx_err_link_failure;
 426	}
 427
 428	if (!vti6_state_check(dst->xfrm, &t->parms.raddr, &t->parms.laddr))
 
 
 
 
 
 429		goto tx_err_link_failure;
 430
 431	tdev = dst->dev;
 432
 433	if (tdev == dev) {
 434		stats->collisions++;
 435		net_warn_ratelimited("%s: Local routing loop detected!\n",
 436				     t->parms.name);
 437		goto tx_err_dst_release;
 438	}
 439
 440	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
 441	skb_dst_set(skb, dst);
 442	skb->dev = skb_dst(skb)->dev;
 443
 444	err = dst_output(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 445	if (net_xmit_eval(err) == 0) {
 446		struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
 447
 448		u64_stats_update_begin(&tstats->syncp);
 449		tstats->tx_bytes += skb->len;
 450		tstats->tx_packets++;
 451		u64_stats_update_end(&tstats->syncp);
 452	} else {
 453		stats->tx_errors++;
 454		stats->tx_aborted_errors++;
 455	}
 456
 457	return 0;
 458tx_err_link_failure:
 459	stats->tx_carrier_errors++;
 460	dst_link_failure(skb);
 461tx_err_dst_release:
 462	dst_release(dst);
 463	return err;
 464}
 465
 466static netdev_tx_t
 467vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
 468{
 469	struct ip6_tnl *t = netdev_priv(dev);
 470	struct net_device_stats *stats = &t->dev->stats;
 471	struct ipv6hdr *ipv6h;
 472	struct flowi fl;
 473	int ret;
 474
 475	memset(&fl, 0, sizeof(fl));
 476	skb->mark = be32_to_cpu(t->parms.o_key);
 477
 478	switch (skb->protocol) {
 479	case htons(ETH_P_IPV6):
 480		ipv6h = ipv6_hdr(skb);
 481
 482		if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
 483		    !ip6_tnl_xmit_ctl(t) || vti6_addr_conflict(t, ipv6h))
 484			goto tx_err;
 485
 486		xfrm_decode_session(skb, &fl, AF_INET6);
 487		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
 488		break;
 489	case htons(ETH_P_IP):
 490		xfrm_decode_session(skb, &fl, AF_INET);
 491		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 492		break;
 493	default:
 494		goto tx_err;
 495	}
 496
 
 
 
 497	ret = vti6_xmit(skb, dev, &fl);
 498	if (ret < 0)
 499		goto tx_err;
 500
 501	return NETDEV_TX_OK;
 502
 503tx_err:
 504	stats->tx_errors++;
 505	stats->tx_dropped++;
 506	kfree_skb(skb);
 507	return NETDEV_TX_OK;
 508}
 509
 510static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 511		    u8 type, u8 code, int offset, __be32 info)
 512{
 513	__be32 spi;
 514	__u32 mark;
 515	struct xfrm_state *x;
 516	struct ip6_tnl *t;
 517	struct ip_esp_hdr *esph;
 518	struct ip_auth_hdr *ah;
 519	struct ip_comp_hdr *ipch;
 520	struct net *net = dev_net(skb->dev);
 521	const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
 522	int protocol = iph->nexthdr;
 523
 524	t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
 525	if (!t)
 526		return -1;
 527
 528	mark = be32_to_cpu(t->parms.o_key);
 529
 530	switch (protocol) {
 531	case IPPROTO_ESP:
 532		esph = (struct ip_esp_hdr *)(skb->data + offset);
 533		spi = esph->spi;
 534		break;
 535	case IPPROTO_AH:
 536		ah = (struct ip_auth_hdr *)(skb->data + offset);
 537		spi = ah->spi;
 538		break;
 539	case IPPROTO_COMP:
 540		ipch = (struct ip_comp_hdr *)(skb->data + offset);
 541		spi = htonl(ntohs(ipch->cpi));
 542		break;
 543	default:
 544		return 0;
 545	}
 546
 547	if (type != ICMPV6_PKT_TOOBIG &&
 548	    type != NDISC_REDIRECT)
 549		return 0;
 550
 551	x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
 552			      spi, protocol, AF_INET6);
 553	if (!x)
 554		return 0;
 555
 556	if (type == NDISC_REDIRECT)
 557		ip6_redirect(skb, net, skb->dev->ifindex, 0);
 
 558	else
 559		ip6_update_pmtu(skb, net, info, 0, 0);
 560	xfrm_state_put(x);
 561
 562	return 0;
 563}
 564
 565static void vti6_link_config(struct ip6_tnl *t)
 566{
 567	struct net_device *dev = t->dev;
 568	struct __ip6_tnl_parm *p = &t->parms;
 
 
 569
 570	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
 571	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
 572
 573	p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
 574		      IP6_TNL_F_CAP_PER_PACKET);
 575	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
 576
 577	if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
 578		dev->flags |= IFF_POINTOPOINT;
 579	else
 580		dev->flags &= ~IFF_POINTOPOINT;
 581
 582	dev->iflink = p->link;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 583}
 584
 585/**
 586 * vti6_tnl_change - update the tunnel parameters
 587 *   @t: tunnel to be changed
 588 *   @p: tunnel configuration parameters
 
 589 *
 590 * Description:
 591 *   vti6_tnl_change() updates the tunnel parameters
 592 **/
 593static int
 594vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
 
 595{
 596	t->parms.laddr = p->laddr;
 597	t->parms.raddr = p->raddr;
 598	t->parms.link = p->link;
 599	t->parms.i_key = p->i_key;
 600	t->parms.o_key = p->o_key;
 601	t->parms.proto = p->proto;
 602	ip6_tnl_dst_reset(t);
 603	vti6_link_config(t);
 
 604	return 0;
 605}
 606
 607static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
 
 608{
 609	struct net *net = dev_net(t->dev);
 610	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 611	int err;
 612
 613	vti6_tnl_unlink(ip6n, t);
 614	synchronize_net();
 615	err = vti6_tnl_change(t, p);
 616	vti6_tnl_link(ip6n, t);
 617	netdev_state_change(t->dev);
 618	return err;
 619}
 620
 621static void
 622vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
 623{
 624	p->laddr = u->laddr;
 625	p->raddr = u->raddr;
 626	p->link = u->link;
 627	p->i_key = u->i_key;
 628	p->o_key = u->o_key;
 629	p->proto = u->proto;
 630
 631	memcpy(p->name, u->name, sizeof(u->name));
 632}
 633
 634static void
 635vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
 636{
 637	u->laddr = p->laddr;
 638	u->raddr = p->raddr;
 639	u->link = p->link;
 640	u->i_key = p->i_key;
 641	u->o_key = p->o_key;
 
 
 
 
 642	u->proto = p->proto;
 643
 644	memcpy(u->name, p->name, sizeof(u->name));
 645}
 646
 647/**
 648 * vti6_tnl_ioctl - configure vti6 tunnels from userspace
 649 *   @dev: virtual device associated with tunnel
 650 *   @ifr: parameters passed from userspace
 651 *   @cmd: command to be performed
 652 *
 653 * Description:
 654 *   vti6_ioctl() is used for managing vti6 tunnels
 655 *   from userspace.
 656 *
 657 *   The possible commands are the following:
 658 *     %SIOCGETTUNNEL: get tunnel parameters for device
 659 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
 660 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
 661 *     %SIOCDELTUNNEL: delete tunnel
 662 *
 663 *   The fallback device "ip6_vti0", created during module
 664 *   initialization, can be used for creating other tunnel devices.
 665 *
 666 * Return:
 667 *   0 on success,
 668 *   %-EFAULT if unable to copy data to or from userspace,
 669 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
 670 *   %-EINVAL if passed tunnel parameters are invalid,
 671 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
 672 *   %-ENODEV if attempting to change or delete a nonexisting device
 673 **/
 674static int
 675vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 676{
 677	int err = 0;
 678	struct ip6_tnl_parm2 p;
 679	struct __ip6_tnl_parm p1;
 680	struct ip6_tnl *t = NULL;
 681	struct net *net = dev_net(dev);
 682	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 683
 684	switch (cmd) {
 685	case SIOCGETTUNNEL:
 686		if (dev == ip6n->fb_tnl_dev) {
 687			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
 688				err = -EFAULT;
 689				break;
 690			}
 691			vti6_parm_from_user(&p1, &p);
 692			t = vti6_locate(net, &p1, 0);
 693		} else {
 694			memset(&p, 0, sizeof(p));
 695		}
 696		if (t == NULL)
 697			t = netdev_priv(dev);
 698		vti6_parm_to_user(&p, &t->parms);
 699		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 700			err = -EFAULT;
 701		break;
 702	case SIOCADDTUNNEL:
 703	case SIOCCHGTUNNEL:
 704		err = -EPERM;
 705		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 706			break;
 707		err = -EFAULT;
 708		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 709			break;
 710		err = -EINVAL;
 711		if (p.proto != IPPROTO_IPV6  && p.proto != 0)
 712			break;
 713		vti6_parm_from_user(&p1, &p);
 714		t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
 715		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
 716			if (t != NULL) {
 717				if (t->dev != dev) {
 718					err = -EEXIST;
 719					break;
 720				}
 721			} else
 722				t = netdev_priv(dev);
 723
 724			err = vti6_update(t, &p1);
 725		}
 726		if (t) {
 727			err = 0;
 728			vti6_parm_to_user(&p, &t->parms);
 729			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 730				err = -EFAULT;
 731
 732		} else
 733			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
 734		break;
 735	case SIOCDELTUNNEL:
 736		err = -EPERM;
 737		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 738			break;
 739
 740		if (dev == ip6n->fb_tnl_dev) {
 741			err = -EFAULT;
 742			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 743				break;
 744			err = -ENOENT;
 745			vti6_parm_from_user(&p1, &p);
 746			t = vti6_locate(net, &p1, 0);
 747			if (t == NULL)
 748				break;
 749			err = -EPERM;
 750			if (t->dev == ip6n->fb_tnl_dev)
 751				break;
 752			dev = t->dev;
 753		}
 754		err = 0;
 755		unregister_netdevice(dev);
 756		break;
 757	default:
 758		err = -EINVAL;
 759	}
 760	return err;
 761}
 762
 763/**
 764 * vti6_tnl_change_mtu - change mtu manually for tunnel device
 765 *   @dev: virtual device associated with tunnel
 766 *   @new_mtu: the new mtu
 767 *
 768 * Return:
 769 *   0 on success,
 770 *   %-EINVAL if mtu too small
 771 **/
 772static int vti6_change_mtu(struct net_device *dev, int new_mtu)
 773{
 774	if (new_mtu < IPV6_MIN_MTU)
 775		return -EINVAL;
 776
 777	dev->mtu = new_mtu;
 778	return 0;
 779}
 780
 781static const struct net_device_ops vti6_netdev_ops = {
 
 782	.ndo_uninit	= vti6_dev_uninit,
 783	.ndo_start_xmit = vti6_tnl_xmit,
 784	.ndo_do_ioctl	= vti6_ioctl,
 785	.ndo_change_mtu = vti6_change_mtu,
 786	.ndo_get_stats64 = ip_tunnel_get_stats64,
 
 787};
 788
 789/**
 790 * vti6_dev_setup - setup virtual tunnel device
 791 *   @dev: virtual device associated with tunnel
 792 *
 793 * Description:
 794 *   Initialize function pointers and device parameters
 795 **/
 796static void vti6_dev_setup(struct net_device *dev)
 797{
 798	struct ip6_tnl *t;
 799
 800	dev->netdev_ops = &vti6_netdev_ops;
 801	dev->destructor = vti6_dev_free;
 
 802
 803	dev->type = ARPHRD_TUNNEL6;
 804	dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
 805	dev->mtu = ETH_DATA_LEN;
 806	t = netdev_priv(dev);
 807	dev->flags |= IFF_NOARP;
 808	dev->addr_len = sizeof(struct in6_addr);
 809	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
 
 
 
 810}
 811
 812/**
 813 * vti6_dev_init_gen - general initializer for all tunnel devices
 814 *   @dev: virtual device associated with tunnel
 815 **/
 816static inline int vti6_dev_init_gen(struct net_device *dev)
 817{
 818	struct ip6_tnl *t = netdev_priv(dev);
 819
 820	t->dev = dev;
 821	t->net = dev_net(dev);
 822	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 823	if (!dev->tstats)
 824		return -ENOMEM;
 825	return 0;
 826}
 827
 828/**
 829 * vti6_dev_init - initializer for all non fallback tunnel devices
 830 *   @dev: virtual device associated with tunnel
 831 **/
 832static int vti6_dev_init(struct net_device *dev)
 833{
 834	struct ip6_tnl *t = netdev_priv(dev);
 835	int err = vti6_dev_init_gen(dev);
 836
 837	if (err)
 838		return err;
 839	vti6_link_config(t);
 840	return 0;
 841}
 842
 843/**
 844 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
 845 *   @dev: fallback device
 846 *
 847 * Return: 0
 848 **/
 849static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
 850{
 851	struct ip6_tnl *t = netdev_priv(dev);
 852	struct net *net = dev_net(dev);
 853	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 854	int err = vti6_dev_init_gen(dev);
 855
 856	if (err)
 857		return err;
 858
 859	t->parms.proto = IPPROTO_IPV6;
 860	dev_hold(dev);
 861
 862	vti6_link_config(t);
 863
 864	rcu_assign_pointer(ip6n->tnls_wc[0], t);
 865	return 0;
 866}
 867
 868static int vti6_validate(struct nlattr *tb[], struct nlattr *data[])
 
 869{
 870	return 0;
 871}
 872
 873static void vti6_netlink_parms(struct nlattr *data[],
 874			       struct __ip6_tnl_parm *parms)
 875{
 876	memset(parms, 0, sizeof(*parms));
 877
 878	if (!data)
 879		return;
 880
 881	if (data[IFLA_VTI_LINK])
 882		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
 883
 884	if (data[IFLA_VTI_LOCAL])
 885		nla_memcpy(&parms->laddr, data[IFLA_VTI_LOCAL],
 886			   sizeof(struct in6_addr));
 887
 888	if (data[IFLA_VTI_REMOTE])
 889		nla_memcpy(&parms->raddr, data[IFLA_VTI_REMOTE],
 890			   sizeof(struct in6_addr));
 891
 892	if (data[IFLA_VTI_IKEY])
 893		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
 894
 895	if (data[IFLA_VTI_OKEY])
 896		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
 
 
 
 897}
 898
 899static int vti6_newlink(struct net *src_net, struct net_device *dev,
 900			struct nlattr *tb[], struct nlattr *data[])
 
 901{
 902	struct net *net = dev_net(dev);
 903	struct ip6_tnl *nt;
 904
 905	nt = netdev_priv(dev);
 906	vti6_netlink_parms(data, &nt->parms);
 907
 908	nt->parms.proto = IPPROTO_IPV6;
 909
 910	if (vti6_locate(net, &nt->parms, 0))
 911		return -EEXIST;
 912
 913	return vti6_tnl_create2(dev);
 914}
 915
 
 
 
 
 
 
 
 
 
 916static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
 917			   struct nlattr *data[])
 
 918{
 919	struct ip6_tnl *t;
 920	struct __ip6_tnl_parm p;
 921	struct net *net = dev_net(dev);
 922	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 923
 924	if (dev == ip6n->fb_tnl_dev)
 925		return -EINVAL;
 926
 927	vti6_netlink_parms(data, &p);
 928
 929	t = vti6_locate(net, &p, 0);
 930
 931	if (t) {
 932		if (t->dev != dev)
 933			return -EEXIST;
 934	} else
 935		t = netdev_priv(dev);
 936
 937	return vti6_update(t, &p);
 938}
 939
 940static size_t vti6_get_size(const struct net_device *dev)
 941{
 942	return
 943		/* IFLA_VTI_LINK */
 944		nla_total_size(4) +
 945		/* IFLA_VTI_LOCAL */
 946		nla_total_size(sizeof(struct in6_addr)) +
 947		/* IFLA_VTI_REMOTE */
 948		nla_total_size(sizeof(struct in6_addr)) +
 949		/* IFLA_VTI_IKEY */
 950		nla_total_size(4) +
 951		/* IFLA_VTI_OKEY */
 952		nla_total_size(4) +
 
 
 953		0;
 954}
 955
 956static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
 957{
 958	struct ip6_tnl *tunnel = netdev_priv(dev);
 959	struct __ip6_tnl_parm *parm = &tunnel->parms;
 960
 961	if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
 962	    nla_put(skb, IFLA_VTI_LOCAL, sizeof(struct in6_addr),
 963		    &parm->laddr) ||
 964	    nla_put(skb, IFLA_VTI_REMOTE, sizeof(struct in6_addr),
 965		    &parm->raddr) ||
 966	    nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
 967	    nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key))
 
 968		goto nla_put_failure;
 969	return 0;
 970
 971nla_put_failure:
 972	return -EMSGSIZE;
 973}
 974
 975static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
 976	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
 977	[IFLA_VTI_LOCAL]	= { .len = sizeof(struct in6_addr) },
 978	[IFLA_VTI_REMOTE]	= { .len = sizeof(struct in6_addr) },
 979	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
 980	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
 
 981};
 982
 983static struct rtnl_link_ops vti6_link_ops __read_mostly = {
 984	.kind		= "vti6",
 985	.maxtype	= IFLA_VTI_MAX,
 986	.policy		= vti6_policy,
 987	.priv_size	= sizeof(struct ip6_tnl),
 988	.setup		= vti6_dev_setup,
 989	.validate	= vti6_validate,
 990	.newlink	= vti6_newlink,
 
 991	.changelink	= vti6_changelink,
 992	.get_size	= vti6_get_size,
 993	.fill_info	= vti6_fill_info,
 
 994};
 995
 996static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n)
 
 997{
 998	int h;
 999	struct ip6_tnl *t;
1000	LIST_HEAD(list);
1001
1002	for (h = 0; h < HASH_SIZE; h++) {
1003		t = rtnl_dereference(ip6n->tnls_r_l[h]);
1004		while (t != NULL) {
1005			unregister_netdevice_queue(t->dev, &list);
1006			t = rtnl_dereference(t->next);
1007		}
1008	}
1009
1010	t = rtnl_dereference(ip6n->tnls_wc[0]);
1011	unregister_netdevice_queue(t->dev, &list);
1012	unregister_netdevice_many(&list);
1013}
1014
1015static int __net_init vti6_init_net(struct net *net)
1016{
1017	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1018	struct ip6_tnl *t = NULL;
1019	int err;
1020
1021	ip6n->tnls[0] = ip6n->tnls_wc;
1022	ip6n->tnls[1] = ip6n->tnls_r_l;
1023
1024	err = -ENOMEM;
1025	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1026					vti6_dev_setup);
1027
1028	if (!ip6n->fb_tnl_dev)
1029		goto err_alloc_dev;
1030	dev_net_set(ip6n->fb_tnl_dev, net);
 
1031
1032	err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1033	if (err < 0)
1034		goto err_register;
1035
1036	err = register_netdev(ip6n->fb_tnl_dev);
1037	if (err < 0)
1038		goto err_register;
1039
1040	t = netdev_priv(ip6n->fb_tnl_dev);
1041
1042	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1043	return 0;
1044
1045err_register:
1046	vti6_dev_free(ip6n->fb_tnl_dev);
1047err_alloc_dev:
1048	return err;
1049}
1050
1051static void __net_exit vti6_exit_net(struct net *net)
1052{
1053	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 
 
1054
1055	rtnl_lock();
1056	vti6_destroy_tunnels(ip6n);
 
 
 
 
1057	rtnl_unlock();
1058}
1059
1060static struct pernet_operations vti6_net_ops = {
1061	.init = vti6_init_net,
1062	.exit = vti6_exit_net,
1063	.id   = &vti6_net_id,
1064	.size = sizeof(struct vti6_net),
1065};
1066
1067static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1068	.handler	=	vti6_rcv,
1069	.cb_handler	=	vti6_rcv_cb,
1070	.err_handler	=	vti6_err,
1071	.priority	=	100,
1072};
1073
1074static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1075	.handler	=	vti6_rcv,
1076	.cb_handler	=	vti6_rcv_cb,
1077	.err_handler	=	vti6_err,
1078	.priority	=	100,
1079};
1080
1081static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1082	.handler	=	vti6_rcv,
1083	.cb_handler	=	vti6_rcv_cb,
1084	.err_handler	=	vti6_err,
1085	.priority	=	100,
1086};
1087
1088/**
1089 * vti6_tunnel_init - register protocol and reserve needed resources
1090 *
1091 * Return: 0 on success
1092 **/
1093static int __init vti6_tunnel_init(void)
1094{
1095	int  err;
 
1096
 
1097	err = register_pernet_device(&vti6_net_ops);
1098	if (err < 0)
1099		goto out_pernet;
1100
 
1101	err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1102	if (err < 0) {
1103		pr_err("%s: can't register vti6 protocol\n", __func__);
1104
1105		goto out;
1106	}
1107
1108	err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1109	if (err < 0) {
1110		xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1111		pr_err("%s: can't register vti6 protocol\n", __func__);
1112
1113		goto out;
1114	}
1115
1116	err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1117	if (err < 0) {
1118		xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1119		xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1120		pr_err("%s: can't register vti6 protocol\n", __func__);
1121
1122		goto out;
1123	}
1124
 
1125	err = rtnl_link_register(&vti6_link_ops);
1126	if (err < 0)
1127		goto rtnl_link_failed;
1128
1129	return 0;
1130
1131rtnl_link_failed:
1132	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
 
1133	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
 
1134	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1135out:
1136	unregister_pernet_device(&vti6_net_ops);
1137out_pernet:
 
1138	return err;
1139}
1140
1141/**
1142 * vti6_tunnel_cleanup - free resources and unregister protocol
1143 **/
1144static void __exit vti6_tunnel_cleanup(void)
1145{
1146	rtnl_link_unregister(&vti6_link_ops);
1147	if (xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP))
1148		pr_info("%s: can't deregister protocol\n", __func__);
1149	if (xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH))
1150		pr_info("%s: can't deregister protocol\n", __func__);
1151	if (xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP))
1152		pr_info("%s: can't deregister protocol\n", __func__);
1153
1154	unregister_pernet_device(&vti6_net_ops);
1155}
1156
1157module_init(vti6_tunnel_init);
1158module_exit(vti6_tunnel_cleanup);
1159MODULE_LICENSE("GPL");
1160MODULE_ALIAS_RTNL_LINK("vti6");
1161MODULE_ALIAS_NETDEV("ip6_vti0");
1162MODULE_AUTHOR("Steffen Klassert");
1163MODULE_DESCRIPTION("IPv6 virtual tunnel interface");