Linux Audio

Check our new training course

Loading...
v4.6
 
   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	struct in6_addr any;
  99
 100	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 101		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 102		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 103		    (t->dev->flags & IFF_UP))
 104			return t;
 105	}
 106
 107	memset(&any, 0, sizeof(any));
 108	hash = HASH(&any, local);
 109	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 110		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 111		    (t->dev->flags & IFF_UP))
 112			return t;
 113	}
 114
 115	hash = HASH(remote, &any);
 116	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 117		if (ipv6_addr_equal(remote, &t->parms.raddr) &&
 118		    (t->dev->flags & IFF_UP))
 119			return t;
 120	}
 121
 122	t = rcu_dereference(ip6n->tnls_wc[0]);
 123	if (t && (t->dev->flags & IFF_UP))
 124		return t;
 125
 126	return NULL;
 127}
 128
 129/**
 130 * vti6_tnl_bucket - get head of list matching given tunnel parameters
 
 131 *   @p: parameters containing tunnel end-points
 132 *
 133 * Description:
 134 *   vti6_tnl_bucket() returns the head of the list matching the
 135 *   &struct in6_addr entries laddr and raddr in @p.
 136 *
 137 * Return: head of IPv6 tunnel list
 138 **/
 139static struct ip6_tnl __rcu **
 140vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
 141{
 142	const struct in6_addr *remote = &p->raddr;
 143	const struct in6_addr *local = &p->laddr;
 144	unsigned int h = 0;
 145	int prio = 0;
 146
 147	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 148		prio = 1;
 149		h = HASH(remote, local);
 150	}
 151	return &ip6n->tnls[prio][h];
 152}
 153
 154static void
 155vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
 156{
 157	struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
 158
 159	rcu_assign_pointer(t->next , rtnl_dereference(*tp));
 160	rcu_assign_pointer(*tp, t);
 161}
 162
 163static void
 164vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
 165{
 166	struct ip6_tnl __rcu **tp;
 167	struct ip6_tnl *iter;
 168
 169	for (tp = vti6_tnl_bucket(ip6n, &t->parms);
 170	     (iter = rtnl_dereference(*tp)) != NULL;
 171	     tp = &iter->next) {
 172		if (t == iter) {
 173			rcu_assign_pointer(*tp, t->next);
 174			break;
 175		}
 176	}
 177}
 178
 179static void vti6_dev_free(struct net_device *dev)
 180{
 181	free_percpu(dev->tstats);
 182	free_netdev(dev);
 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	err = register_netdevice(dev);
 193	if (err < 0)
 194		goto out;
 195
 196	strcpy(t->parms.name, dev->name);
 197	dev->rtnl_link_ops = &vti6_link_ops;
 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		strlcpy(name, p->name, IFNAMSIZ);
 217	else
 
 
 218		sprintf(name, "ip6_vti%%d");
 
 219
 220	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
 221	if (!dev)
 222		goto failed;
 223
 224	dev_net_set(dev, net);
 225
 226	t = netdev_priv(dev);
 227	t->parms = *p;
 228	t->net = dev_net(dev);
 229
 230	err = vti6_tnl_create2(dev);
 231	if (err < 0)
 232		goto failed_free;
 233
 234	return t;
 235
 236failed_free:
 237	vti6_dev_free(dev);
 238failed:
 239	return NULL;
 240}
 241
 242/**
 243 * vti6_locate - find or create tunnel matching given parameters
 244 *   @net: network namespace
 245 *   @p: tunnel parameters
 246 *   @create: != 0 if allowed to create new tunnel if no match found
 247 *
 248 * Description:
 249 *   vti6_locate() first tries to locate an existing tunnel
 250 *   based on @parms. If this is unsuccessful, but @create is set a new
 251 *   tunnel device is created and registered for use.
 252 *
 253 * Return:
 254 *   matching tunnel or NULL
 255 **/
 256static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
 257				   int create)
 258{
 259	const struct in6_addr *remote = &p->raddr;
 260	const struct in6_addr *local = &p->laddr;
 261	struct ip6_tnl __rcu **tp;
 262	struct ip6_tnl *t;
 263	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 264
 265	for (tp = vti6_tnl_bucket(ip6n, p);
 266	     (t = rtnl_dereference(*tp)) != NULL;
 267	     tp = &t->next) {
 268		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 269		    ipv6_addr_equal(remote, &t->parms.raddr)) {
 270			if (create)
 271				return NULL;
 272
 273			return t;
 274		}
 275	}
 276	if (!create)
 277		return NULL;
 278	return vti6_tnl_create(net, p);
 279}
 280
 281/**
 282 * vti6_dev_uninit - tunnel device uninitializer
 283 *   @dev: the device to be destroyed
 284 *
 285 * Description:
 286 *   vti6_dev_uninit() removes tunnel from its list
 287 **/
 288static void vti6_dev_uninit(struct net_device *dev)
 289{
 290	struct ip6_tnl *t = netdev_priv(dev);
 291	struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
 292
 293	if (dev == ip6n->fb_tnl_dev)
 294		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 295	else
 296		vti6_tnl_unlink(ip6n, t);
 297	dev_put(dev);
 298}
 299
 300static int vti6_rcv(struct sk_buff *skb)
 
 301{
 302	struct ip6_tnl *t;
 303	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 304
 305	rcu_read_lock();
 306	t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
 307	if (t) {
 308		if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
 309			rcu_read_unlock();
 310			goto discard;
 311		}
 312
 313		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 314			rcu_read_unlock();
 315			return 0;
 316		}
 317
 
 318		if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
 319			t->dev->stats.rx_dropped++;
 320			rcu_read_unlock();
 321			goto discard;
 322		}
 323
 324		XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
 325
 326		rcu_read_unlock();
 327
 328		return xfrm6_rcv(skb);
 
 
 
 329	}
 330	rcu_read_unlock();
 331	return -EINVAL;
 332discard:
 333	kfree_skb(skb);
 334	return 0;
 335}
 336
 
 
 
 
 
 
 
 337static int vti6_rcv_cb(struct sk_buff *skb, int err)
 338{
 339	unsigned short family;
 340	struct net_device *dev;
 341	struct pcpu_sw_netstats *tstats;
 342	struct xfrm_state *x;
 
 343	struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
 344	u32 orig_mark = skb->mark;
 345	int ret;
 346
 347	if (!t)
 348		return 1;
 349
 350	dev = t->dev;
 351
 352	if (err) {
 353		dev->stats.rx_errors++;
 354		dev->stats.rx_dropped++;
 355
 356		return 0;
 357	}
 358
 359	x = xfrm_input_state(skb);
 360	family = x->inner_mode->afinfo->family;
 
 
 
 
 
 
 
 
 
 
 
 
 361
 362	skb->mark = be32_to_cpu(t->parms.i_key);
 363	ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
 364	skb->mark = orig_mark;
 365
 366	if (!ret)
 367		return -EPERM;
 368
 369	skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
 370	skb->dev = dev;
 371
 372	tstats = this_cpu_ptr(dev->tstats);
 373	u64_stats_update_begin(&tstats->syncp);
 374	tstats->rx_packets++;
 375	tstats->rx_bytes += skb->len;
 376	u64_stats_update_end(&tstats->syncp);
 377
 378	return 0;
 379}
 380
 381/**
 382 * vti6_addr_conflict - compare packet addresses to tunnel's own
 383 *   @t: the outgoing tunnel device
 384 *   @hdr: IPv6 header from the incoming packet
 385 *
 386 * Description:
 387 *   Avoid trivial tunneling loop by checking that tunnel exit-point
 388 *   doesn't match source of incoming packet.
 389 *
 390 * Return:
 391 *   1 if conflict,
 392 *   0 else
 393 **/
 394static inline bool
 395vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 396{
 397	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 398}
 399
 400static bool vti6_state_check(const struct xfrm_state *x,
 401			     const struct in6_addr *dst,
 402			     const struct in6_addr *src)
 403{
 404	xfrm_address_t *daddr = (xfrm_address_t *)dst;
 405	xfrm_address_t *saddr = (xfrm_address_t *)src;
 406
 407	/* if there is no transform then this tunnel is not functional.
 408	 * Or if the xfrm is not mode tunnel.
 409	 */
 410	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
 411	    x->props.family != AF_INET6)
 412		return false;
 413
 414	if (ipv6_addr_any(dst))
 415		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
 416
 417	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
 418		return false;
 419
 420	return true;
 421}
 422
 423/**
 424 * vti6_xmit - send a packet
 425 *   @skb: the outgoing socket buffer
 426 *   @dev: the outgoing tunnel device
 427 *   @fl: the flow informations for the xfrm_lookup
 428 **/
 429static int
 430vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 431{
 432	struct ip6_tnl *t = netdev_priv(dev);
 433	struct net_device_stats *stats = &t->dev->stats;
 434	struct dst_entry *dst = skb_dst(skb);
 435	struct net_device *tdev;
 436	struct xfrm_state *x;
 
 437	int err = -1;
 438	int mtu;
 439
 440	if (!dst)
 441		goto tx_err_link_failure;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 442
 443	dst_hold(dst);
 444	dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
 445	if (IS_ERR(dst)) {
 446		err = PTR_ERR(dst);
 447		dst = NULL;
 448		goto tx_err_link_failure;
 449	}
 450
 
 
 
 451	x = dst->xfrm;
 452	if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
 453		goto tx_err_link_failure;
 454
 455	if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
 456			      (const struct in6_addr *)&x->id.daddr))
 457		goto tx_err_link_failure;
 458
 459	tdev = dst->dev;
 460
 461	if (tdev == dev) {
 462		stats->collisions++;
 463		net_warn_ratelimited("%s: Local routing loop detected!\n",
 464				     t->parms.name);
 465		goto tx_err_dst_release;
 466	}
 467
 468	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
 469	skb_dst_set(skb, dst);
 470	skb->dev = skb_dst(skb)->dev;
 471
 472	mtu = dst_mtu(dst);
 473	if (!skb->ignore_df && skb->len > mtu) {
 474		skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu);
 475
 476		if (skb->protocol == htons(ETH_P_IPV6))
 477			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 478		else
 479			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 480				  htonl(mtu));
 481
 482		return -EMSGSIZE;
 
 
 
 
 
 
 
 
 
 483	}
 484
 485	err = dst_output(t->net, skb->sk, skb);
 486	if (net_xmit_eval(err) == 0) {
 487		struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
 
 488
 489		u64_stats_update_begin(&tstats->syncp);
 490		tstats->tx_bytes += skb->len;
 491		tstats->tx_packets++;
 492		u64_stats_update_end(&tstats->syncp);
 493	} else {
 494		stats->tx_errors++;
 495		stats->tx_aborted_errors++;
 496	}
 497
 498	return 0;
 499tx_err_link_failure:
 500	stats->tx_carrier_errors++;
 501	dst_link_failure(skb);
 502tx_err_dst_release:
 503	dst_release(dst);
 504	return err;
 505}
 506
 507static netdev_tx_t
 508vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
 509{
 510	struct ip6_tnl *t = netdev_priv(dev);
 511	struct net_device_stats *stats = &t->dev->stats;
 512	struct ipv6hdr *ipv6h;
 513	struct flowi fl;
 514	int ret;
 515
 
 
 
 516	memset(&fl, 0, sizeof(fl));
 517
 518	switch (skb->protocol) {
 519	case htons(ETH_P_IPV6):
 520		ipv6h = ipv6_hdr(skb);
 521
 522		if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
 523		    vti6_addr_conflict(t, ipv6h))
 524			goto tx_err;
 525
 526		xfrm_decode_session(skb, &fl, AF_INET6);
 527		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
 
 528		break;
 529	case htons(ETH_P_IP):
 530		xfrm_decode_session(skb, &fl, AF_INET);
 531		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 
 532		break;
 533	default:
 534		goto tx_err;
 535	}
 536
 537	/* override mark with tunnel output key */
 538	fl.flowi_mark = be32_to_cpu(t->parms.o_key);
 539
 540	ret = vti6_xmit(skb, dev, &fl);
 541	if (ret < 0)
 542		goto tx_err;
 543
 544	return NETDEV_TX_OK;
 545
 546tx_err:
 547	stats->tx_errors++;
 548	stats->tx_dropped++;
 549	kfree_skb(skb);
 550	return NETDEV_TX_OK;
 551}
 552
 553static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 554		    u8 type, u8 code, int offset, __be32 info)
 555{
 556	__be32 spi;
 557	__u32 mark;
 558	struct xfrm_state *x;
 559	struct ip6_tnl *t;
 560	struct ip_esp_hdr *esph;
 561	struct ip_auth_hdr *ah;
 562	struct ip_comp_hdr *ipch;
 563	struct net *net = dev_net(skb->dev);
 564	const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
 565	int protocol = iph->nexthdr;
 566
 567	t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
 568	if (!t)
 569		return -1;
 570
 571	mark = be32_to_cpu(t->parms.o_key);
 572
 573	switch (protocol) {
 574	case IPPROTO_ESP:
 575		esph = (struct ip_esp_hdr *)(skb->data + offset);
 576		spi = esph->spi;
 577		break;
 578	case IPPROTO_AH:
 579		ah = (struct ip_auth_hdr *)(skb->data + offset);
 580		spi = ah->spi;
 581		break;
 582	case IPPROTO_COMP:
 583		ipch = (struct ip_comp_hdr *)(skb->data + offset);
 584		spi = htonl(ntohs(ipch->cpi));
 585		break;
 586	default:
 587		return 0;
 588	}
 589
 590	if (type != ICMPV6_PKT_TOOBIG &&
 591	    type != NDISC_REDIRECT)
 592		return 0;
 593
 594	x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
 595			      spi, protocol, AF_INET6);
 596	if (!x)
 597		return 0;
 598
 599	if (type == NDISC_REDIRECT)
 600		ip6_redirect(skb, net, skb->dev->ifindex, 0);
 
 601	else
 602		ip6_update_pmtu(skb, net, info, 0, 0);
 603	xfrm_state_put(x);
 604
 605	return 0;
 606}
 607
 608static void vti6_link_config(struct ip6_tnl *t)
 609{
 610	struct net_device *dev = t->dev;
 611	struct __ip6_tnl_parm *p = &t->parms;
 
 
 612
 613	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
 614	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
 615
 616	p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
 617		      IP6_TNL_F_CAP_PER_PACKET);
 618	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
 619
 620	if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
 621		dev->flags |= IFF_POINTOPOINT;
 622	else
 623		dev->flags &= ~IFF_POINTOPOINT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 624}
 625
 626/**
 627 * vti6_tnl_change - update the tunnel parameters
 628 *   @t: tunnel to be changed
 629 *   @p: tunnel configuration parameters
 
 630 *
 631 * Description:
 632 *   vti6_tnl_change() updates the tunnel parameters
 633 **/
 634static int
 635vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
 
 636{
 637	t->parms.laddr = p->laddr;
 638	t->parms.raddr = p->raddr;
 639	t->parms.link = p->link;
 640	t->parms.i_key = p->i_key;
 641	t->parms.o_key = p->o_key;
 642	t->parms.proto = p->proto;
 
 643	dst_cache_reset(&t->dst_cache);
 644	vti6_link_config(t);
 645	return 0;
 646}
 647
 648static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
 
 649{
 650	struct net *net = dev_net(t->dev);
 651	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 652	int err;
 653
 654	vti6_tnl_unlink(ip6n, t);
 655	synchronize_net();
 656	err = vti6_tnl_change(t, p);
 657	vti6_tnl_link(ip6n, t);
 658	netdev_state_change(t->dev);
 659	return err;
 660}
 661
 662static void
 663vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
 664{
 665	p->laddr = u->laddr;
 666	p->raddr = u->raddr;
 667	p->link = u->link;
 668	p->i_key = u->i_key;
 669	p->o_key = u->o_key;
 670	p->proto = u->proto;
 671
 672	memcpy(p->name, u->name, sizeof(u->name));
 673}
 674
 675static void
 676vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
 677{
 678	u->laddr = p->laddr;
 679	u->raddr = p->raddr;
 680	u->link = p->link;
 681	u->i_key = p->i_key;
 682	u->o_key = p->o_key;
 
 
 
 
 683	u->proto = p->proto;
 684
 685	memcpy(u->name, p->name, sizeof(u->name));
 686}
 687
 688/**
 689 * vti6_tnl_ioctl - configure vti6 tunnels from userspace
 690 *   @dev: virtual device associated with tunnel
 691 *   @ifr: parameters passed from userspace
 
 692 *   @cmd: command to be performed
 693 *
 694 * Description:
 695 *   vti6_ioctl() is used for managing vti6 tunnels
 696 *   from userspace.
 697 *
 698 *   The possible commands are the following:
 699 *     %SIOCGETTUNNEL: get tunnel parameters for device
 700 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
 701 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
 702 *     %SIOCDELTUNNEL: delete tunnel
 703 *
 704 *   The fallback device "ip6_vti0", created during module
 705 *   initialization, can be used for creating other tunnel devices.
 706 *
 707 * Return:
 708 *   0 on success,
 709 *   %-EFAULT if unable to copy data to or from userspace,
 710 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
 711 *   %-EINVAL if passed tunnel parameters are invalid,
 712 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
 713 *   %-ENODEV if attempting to change or delete a nonexisting device
 714 **/
 715static int
 716vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 717{
 718	int err = 0;
 719	struct ip6_tnl_parm2 p;
 720	struct __ip6_tnl_parm p1;
 721	struct ip6_tnl *t = NULL;
 722	struct net *net = dev_net(dev);
 723	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 724
 
 
 725	switch (cmd) {
 726	case SIOCGETTUNNEL:
 727		if (dev == ip6n->fb_tnl_dev) {
 728			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
 729				err = -EFAULT;
 730				break;
 731			}
 732			vti6_parm_from_user(&p1, &p);
 733			t = vti6_locate(net, &p1, 0);
 734		} else {
 735			memset(&p, 0, sizeof(p));
 736		}
 737		if (!t)
 738			t = netdev_priv(dev);
 739		vti6_parm_to_user(&p, &t->parms);
 740		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 741			err = -EFAULT;
 742		break;
 743	case SIOCADDTUNNEL:
 744	case SIOCCHGTUNNEL:
 745		err = -EPERM;
 746		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 747			break;
 748		err = -EFAULT;
 749		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 750			break;
 751		err = -EINVAL;
 752		if (p.proto != IPPROTO_IPV6  && p.proto != 0)
 753			break;
 754		vti6_parm_from_user(&p1, &p);
 755		t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
 756		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
 757			if (t) {
 758				if (t->dev != dev) {
 759					err = -EEXIST;
 760					break;
 761				}
 762			} else
 763				t = netdev_priv(dev);
 764
 765			err = vti6_update(t, &p1);
 766		}
 767		if (t) {
 768			err = 0;
 769			vti6_parm_to_user(&p, &t->parms);
 770			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 771				err = -EFAULT;
 772
 773		} else
 774			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
 775		break;
 776	case SIOCDELTUNNEL:
 777		err = -EPERM;
 778		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 779			break;
 780
 781		if (dev == ip6n->fb_tnl_dev) {
 782			err = -EFAULT;
 783			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
 784				break;
 785			err = -ENOENT;
 786			vti6_parm_from_user(&p1, &p);
 787			t = vti6_locate(net, &p1, 0);
 788			if (!t)
 789				break;
 790			err = -EPERM;
 791			if (t->dev == ip6n->fb_tnl_dev)
 792				break;
 793			dev = t->dev;
 794		}
 795		err = 0;
 796		unregister_netdevice(dev);
 797		break;
 798	default:
 799		err = -EINVAL;
 800	}
 801	return err;
 802}
 803
 804/**
 805 * vti6_tnl_change_mtu - change mtu manually for tunnel device
 806 *   @dev: virtual device associated with tunnel
 807 *   @new_mtu: the new mtu
 808 *
 809 * Return:
 810 *   0 on success,
 811 *   %-EINVAL if mtu too small
 812 **/
 813static int vti6_change_mtu(struct net_device *dev, int new_mtu)
 814{
 815	if (new_mtu < IPV6_MIN_MTU)
 816		return -EINVAL;
 817
 818	dev->mtu = new_mtu;
 819	return 0;
 820}
 821
 822static const struct net_device_ops vti6_netdev_ops = {
 823	.ndo_init	= vti6_dev_init,
 824	.ndo_uninit	= vti6_dev_uninit,
 825	.ndo_start_xmit = vti6_tnl_xmit,
 826	.ndo_do_ioctl	= vti6_ioctl,
 827	.ndo_change_mtu = vti6_change_mtu,
 828	.ndo_get_stats64 = ip_tunnel_get_stats64,
 829	.ndo_get_iflink = ip6_tnl_get_iflink,
 830};
 831
 832/**
 833 * vti6_dev_setup - setup virtual tunnel device
 834 *   @dev: virtual device associated with tunnel
 835 *
 836 * Description:
 837 *   Initialize function pointers and device parameters
 838 **/
 839static void vti6_dev_setup(struct net_device *dev)
 840{
 841	dev->netdev_ops = &vti6_netdev_ops;
 842	dev->destructor = vti6_dev_free;
 
 
 843
 844	dev->type = ARPHRD_TUNNEL6;
 845	dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
 846	dev->mtu = ETH_DATA_LEN;
 847	dev->flags |= IFF_NOARP;
 848	dev->addr_len = sizeof(struct in6_addr);
 849	netif_keep_dst(dev);
 
 
 
 850}
 851
 852/**
 853 * vti6_dev_init_gen - general initializer for all tunnel devices
 854 *   @dev: virtual device associated with tunnel
 855 **/
 856static inline int vti6_dev_init_gen(struct net_device *dev)
 857{
 858	struct ip6_tnl *t = netdev_priv(dev);
 859
 860	t->dev = dev;
 861	t->net = dev_net(dev);
 862	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 863	if (!dev->tstats)
 864		return -ENOMEM;
 
 865	return 0;
 866}
 867
 868/**
 869 * vti6_dev_init - initializer for all non fallback tunnel devices
 870 *   @dev: virtual device associated with tunnel
 871 **/
 872static int vti6_dev_init(struct net_device *dev)
 873{
 874	struct ip6_tnl *t = netdev_priv(dev);
 875	int err = vti6_dev_init_gen(dev);
 876
 877	if (err)
 878		return err;
 879	vti6_link_config(t);
 880	return 0;
 881}
 882
 883/**
 884 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
 885 *   @dev: fallback device
 886 *
 887 * Return: 0
 888 **/
 889static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
 890{
 891	struct ip6_tnl *t = netdev_priv(dev);
 892	struct net *net = dev_net(dev);
 893	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 894
 895	t->parms.proto = IPPROTO_IPV6;
 896	dev_hold(dev);
 897
 898	rcu_assign_pointer(ip6n->tnls_wc[0], t);
 899	return 0;
 900}
 901
 902static int vti6_validate(struct nlattr *tb[], struct nlattr *data[])
 
 903{
 904	return 0;
 905}
 906
 907static void vti6_netlink_parms(struct nlattr *data[],
 908			       struct __ip6_tnl_parm *parms)
 909{
 910	memset(parms, 0, sizeof(*parms));
 911
 912	if (!data)
 913		return;
 914
 915	if (data[IFLA_VTI_LINK])
 916		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
 917
 918	if (data[IFLA_VTI_LOCAL])
 919		parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
 920
 921	if (data[IFLA_VTI_REMOTE])
 922		parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
 923
 924	if (data[IFLA_VTI_IKEY])
 925		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
 926
 927	if (data[IFLA_VTI_OKEY])
 928		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
 
 
 
 929}
 930
 931static int vti6_newlink(struct net *src_net, struct net_device *dev,
 932			struct nlattr *tb[], struct nlattr *data[])
 
 933{
 934	struct net *net = dev_net(dev);
 935	struct ip6_tnl *nt;
 936
 937	nt = netdev_priv(dev);
 938	vti6_netlink_parms(data, &nt->parms);
 939
 940	nt->parms.proto = IPPROTO_IPV6;
 941
 942	if (vti6_locate(net, &nt->parms, 0))
 943		return -EEXIST;
 944
 945	return vti6_tnl_create2(dev);
 946}
 947
 948static void vti6_dellink(struct net_device *dev, struct list_head *head)
 949{
 950	struct net *net = dev_net(dev);
 951	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 952
 953	if (dev != ip6n->fb_tnl_dev)
 954		unregister_netdevice_queue(dev, head);
 955}
 956
 957static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
 958			   struct nlattr *data[])
 
 959{
 960	struct ip6_tnl *t;
 961	struct __ip6_tnl_parm p;
 962	struct net *net = dev_net(dev);
 963	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 964
 965	if (dev == ip6n->fb_tnl_dev)
 966		return -EINVAL;
 967
 968	vti6_netlink_parms(data, &p);
 969
 970	t = vti6_locate(net, &p, 0);
 971
 972	if (t) {
 973		if (t->dev != dev)
 974			return -EEXIST;
 975	} else
 976		t = netdev_priv(dev);
 977
 978	return vti6_update(t, &p);
 979}
 980
 981static size_t vti6_get_size(const struct net_device *dev)
 982{
 983	return
 984		/* IFLA_VTI_LINK */
 985		nla_total_size(4) +
 986		/* IFLA_VTI_LOCAL */
 987		nla_total_size(sizeof(struct in6_addr)) +
 988		/* IFLA_VTI_REMOTE */
 989		nla_total_size(sizeof(struct in6_addr)) +
 990		/* IFLA_VTI_IKEY */
 991		nla_total_size(4) +
 992		/* IFLA_VTI_OKEY */
 993		nla_total_size(4) +
 
 
 994		0;
 995}
 996
 997static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
 998{
 999	struct ip6_tnl *tunnel = netdev_priv(dev);
1000	struct __ip6_tnl_parm *parm = &tunnel->parms;
1001
1002	if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
1003	    nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
1004	    nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
1005	    nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
1006	    nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key))
 
1007		goto nla_put_failure;
1008	return 0;
1009
1010nla_put_failure:
1011	return -EMSGSIZE;
1012}
1013
1014static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
1015	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
1016	[IFLA_VTI_LOCAL]	= { .len = sizeof(struct in6_addr) },
1017	[IFLA_VTI_REMOTE]	= { .len = sizeof(struct in6_addr) },
1018	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
1019	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
 
1020};
1021
1022static struct rtnl_link_ops vti6_link_ops __read_mostly = {
1023	.kind		= "vti6",
1024	.maxtype	= IFLA_VTI_MAX,
1025	.policy		= vti6_policy,
1026	.priv_size	= sizeof(struct ip6_tnl),
1027	.setup		= vti6_dev_setup,
1028	.validate	= vti6_validate,
1029	.newlink	= vti6_newlink,
1030	.dellink	= vti6_dellink,
1031	.changelink	= vti6_changelink,
1032	.get_size	= vti6_get_size,
1033	.fill_info	= vti6_fill_info,
1034	.get_link_net	= ip6_tnl_get_link_net,
1035};
1036
1037static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n)
 
1038{
1039	int h;
1040	struct ip6_tnl *t;
1041	LIST_HEAD(list);
1042
1043	for (h = 0; h < HASH_SIZE; h++) {
1044		t = rtnl_dereference(ip6n->tnls_r_l[h]);
1045		while (t) {
1046			unregister_netdevice_queue(t->dev, &list);
1047			t = rtnl_dereference(t->next);
1048		}
1049	}
1050
1051	t = rtnl_dereference(ip6n->tnls_wc[0]);
1052	unregister_netdevice_queue(t->dev, &list);
1053	unregister_netdevice_many(&list);
1054}
1055
1056static int __net_init vti6_init_net(struct net *net)
1057{
1058	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1059	struct ip6_tnl *t = NULL;
1060	int err;
1061
1062	ip6n->tnls[0] = ip6n->tnls_wc;
1063	ip6n->tnls[1] = ip6n->tnls_r_l;
1064
 
 
1065	err = -ENOMEM;
1066	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1067					NET_NAME_UNKNOWN, vti6_dev_setup);
1068
1069	if (!ip6n->fb_tnl_dev)
1070		goto err_alloc_dev;
1071	dev_net_set(ip6n->fb_tnl_dev, net);
1072	ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
1073
1074	err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1075	if (err < 0)
1076		goto err_register;
1077
1078	err = register_netdev(ip6n->fb_tnl_dev);
1079	if (err < 0)
1080		goto err_register;
1081
1082	t = netdev_priv(ip6n->fb_tnl_dev);
1083
1084	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1085	return 0;
1086
1087err_register:
1088	vti6_dev_free(ip6n->fb_tnl_dev);
1089err_alloc_dev:
1090	return err;
1091}
1092
1093static void __net_exit vti6_exit_net(struct net *net)
1094{
1095	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 
 
1096
1097	rtnl_lock();
1098	vti6_destroy_tunnels(ip6n);
 
 
 
 
1099	rtnl_unlock();
1100}
1101
1102static struct pernet_operations vti6_net_ops = {
1103	.init = vti6_init_net,
1104	.exit = vti6_exit_net,
1105	.id   = &vti6_net_id,
1106	.size = sizeof(struct vti6_net),
1107};
1108
1109static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1110	.handler	=	vti6_rcv,
 
1111	.cb_handler	=	vti6_rcv_cb,
1112	.err_handler	=	vti6_err,
1113	.priority	=	100,
1114};
1115
1116static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1117	.handler	=	vti6_rcv,
 
1118	.cb_handler	=	vti6_rcv_cb,
1119	.err_handler	=	vti6_err,
1120	.priority	=	100,
1121};
1122
1123static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1124	.handler	=	vti6_rcv,
 
1125	.cb_handler	=	vti6_rcv_cb,
1126	.err_handler	=	vti6_err,
1127	.priority	=	100,
1128};
1129
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1130/**
1131 * vti6_tunnel_init - register protocol and reserve needed resources
1132 *
1133 * Return: 0 on success
1134 **/
1135static int __init vti6_tunnel_init(void)
1136{
1137	const char *msg;
1138	int err;
1139
1140	msg = "tunnel device";
1141	err = register_pernet_device(&vti6_net_ops);
1142	if (err < 0)
1143		goto pernet_dev_failed;
1144
1145	msg = "tunnel protocols";
1146	err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1147	if (err < 0)
1148		goto xfrm_proto_esp_failed;
1149	err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1150	if (err < 0)
1151		goto xfrm_proto_ah_failed;
1152	err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1153	if (err < 0)
1154		goto xfrm_proto_comp_failed;
 
 
 
 
 
 
 
 
 
1155
1156	msg = "netlink interface";
1157	err = rtnl_link_register(&vti6_link_ops);
1158	if (err < 0)
1159		goto rtnl_link_failed;
1160
1161	return 0;
1162
1163rtnl_link_failed:
 
 
 
 
 
 
1164	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1165xfrm_proto_comp_failed:
1166	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1167xfrm_proto_ah_failed:
1168	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1169xfrm_proto_esp_failed:
1170	unregister_pernet_device(&vti6_net_ops);
1171pernet_dev_failed:
1172	pr_err("vti6 init: failed to register %s\n", msg);
1173	return err;
1174}
1175
1176/**
1177 * vti6_tunnel_cleanup - free resources and unregister protocol
1178 **/
1179static void __exit vti6_tunnel_cleanup(void)
1180{
1181	rtnl_link_unregister(&vti6_link_ops);
 
 
 
 
1182	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1183	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1184	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1185	unregister_pernet_device(&vti6_net_ops);
1186}
1187
1188module_init(vti6_tunnel_init);
1189module_exit(vti6_tunnel_cleanup);
1190MODULE_LICENSE("GPL");
1191MODULE_ALIAS_RTNL_LINK("vti6");
1192MODULE_ALIAS_NETDEV("ip6_vti0");
1193MODULE_AUTHOR("Steffen Klassert");
1194MODULE_DESCRIPTION("IPv6 virtual tunnel interface");
v6.8
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	IPv6 virtual tunneling interface
   4 *
   5 *	Copyright (C) 2013 secunet Security Networks AG
   6 *
   7 *	Author:
   8 *	Steffen Klassert <steffen.klassert@secunet.com>
   9 *
  10 *	Based on:
  11 *	net/ipv6/ip6_tunnel.c
 
 
 
 
 
  12 */
  13
  14#include <linux/module.h>
  15#include <linux/capability.h>
  16#include <linux/errno.h>
  17#include <linux/types.h>
  18#include <linux/sockios.h>
  19#include <linux/icmp.h>
  20#include <linux/if.h>
  21#include <linux/in.h>
  22#include <linux/ip.h>
  23#include <linux/net.h>
  24#include <linux/in6.h>
  25#include <linux/netdevice.h>
  26#include <linux/if_arp.h>
  27#include <linux/icmpv6.h>
  28#include <linux/init.h>
  29#include <linux/route.h>
  30#include <linux/rtnetlink.h>
  31#include <linux/netfilter_ipv6.h>
  32#include <linux/slab.h>
  33#include <linux/hash.h>
  34
  35#include <linux/uaccess.h>
  36#include <linux/atomic.h>
  37
  38#include <net/icmp.h>
  39#include <net/ip.h>
  40#include <net/ip_tunnels.h>
  41#include <net/ipv6.h>
  42#include <net/ip6_route.h>
  43#include <net/addrconf.h>
  44#include <net/ip6_tunnel.h>
  45#include <net/xfrm.h>
  46#include <net/net_namespace.h>
  47#include <net/netns/generic.h>
  48#include <linux/etherdevice.h>
  49
  50#define IP6_VTI_HASH_SIZE_SHIFT  5
  51#define IP6_VTI_HASH_SIZE (1 << IP6_VTI_HASH_SIZE_SHIFT)
  52
  53static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  54{
  55	u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  56
  57	return hash_32(hash, IP6_VTI_HASH_SIZE_SHIFT);
  58}
  59
  60static int vti6_dev_init(struct net_device *dev);
  61static void vti6_dev_setup(struct net_device *dev);
  62static struct rtnl_link_ops vti6_link_ops __read_mostly;
  63
  64static unsigned int vti6_net_id __read_mostly;
  65struct vti6_net {
  66	/* the vti6 tunnel fallback device */
  67	struct net_device *fb_tnl_dev;
  68	/* lists for storing tunnels in use */
  69	struct ip6_tnl __rcu *tnls_r_l[IP6_VTI_HASH_SIZE];
  70	struct ip6_tnl __rcu *tnls_wc[1];
  71	struct ip6_tnl __rcu **tnls[2];
  72};
  73
  74#define for_each_vti6_tunnel_rcu(start) \
  75	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
  76
  77/**
  78 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses
  79 *   @net: network namespace
  80 *   @remote: the address of the tunnel exit-point
  81 *   @local: the address of the tunnel entry-point
  82 *
  83 * Return:
  84 *   tunnel matching given end-points if found,
  85 *   else fallback tunnel if its device is up,
  86 *   else %NULL
  87 **/
  88static struct ip6_tnl *
  89vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
  90		const struct in6_addr *local)
  91{
  92	unsigned int hash = HASH(remote, local);
  93	struct ip6_tnl *t;
  94	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
  95	struct in6_addr any;
  96
  97	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
  98		if (ipv6_addr_equal(local, &t->parms.laddr) &&
  99		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 100		    (t->dev->flags & IFF_UP))
 101			return t;
 102	}
 103
 104	memset(&any, 0, sizeof(any));
 105	hash = HASH(&any, local);
 106	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 107		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 108		    (t->dev->flags & IFF_UP))
 109			return t;
 110	}
 111
 112	hash = HASH(remote, &any);
 113	for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 114		if (ipv6_addr_equal(remote, &t->parms.raddr) &&
 115		    (t->dev->flags & IFF_UP))
 116			return t;
 117	}
 118
 119	t = rcu_dereference(ip6n->tnls_wc[0]);
 120	if (t && (t->dev->flags & IFF_UP))
 121		return t;
 122
 123	return NULL;
 124}
 125
 126/**
 127 * vti6_tnl_bucket - get head of list matching given tunnel parameters
 128 *   @ip6n: the private data for ip6_vti in the netns
 129 *   @p: parameters containing tunnel end-points
 130 *
 131 * Description:
 132 *   vti6_tnl_bucket() returns the head of the list matching the
 133 *   &struct in6_addr entries laddr and raddr in @p.
 134 *
 135 * Return: head of IPv6 tunnel list
 136 **/
 137static struct ip6_tnl __rcu **
 138vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
 139{
 140	const struct in6_addr *remote = &p->raddr;
 141	const struct in6_addr *local = &p->laddr;
 142	unsigned int h = 0;
 143	int prio = 0;
 144
 145	if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 146		prio = 1;
 147		h = HASH(remote, local);
 148	}
 149	return &ip6n->tnls[prio][h];
 150}
 151
 152static void
 153vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
 154{
 155	struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
 156
 157	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
 158	rcu_assign_pointer(*tp, t);
 159}
 160
 161static void
 162vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
 163{
 164	struct ip6_tnl __rcu **tp;
 165	struct ip6_tnl *iter;
 166
 167	for (tp = vti6_tnl_bucket(ip6n, &t->parms);
 168	     (iter = rtnl_dereference(*tp)) != NULL;
 169	     tp = &iter->next) {
 170		if (t == iter) {
 171			rcu_assign_pointer(*tp, t->next);
 172			break;
 173		}
 174	}
 175}
 176
 177static void vti6_dev_free(struct net_device *dev)
 178{
 179	free_percpu(dev->tstats);
 
 180}
 181
 182static int vti6_tnl_create2(struct net_device *dev)
 183{
 184	struct ip6_tnl *t = netdev_priv(dev);
 185	struct net *net = dev_net(dev);
 186	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 187	int err;
 188
 189	dev->rtnl_link_ops = &vti6_link_ops;
 190	err = register_netdevice(dev);
 191	if (err < 0)
 192		goto out;
 193
 194	strcpy(t->parms.name, dev->name);
 
 195
 
 196	vti6_tnl_link(ip6n, t);
 197
 198	return 0;
 199
 200out:
 201	return err;
 202}
 203
 204static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 205{
 206	struct net_device *dev;
 207	struct ip6_tnl *t;
 208	char name[IFNAMSIZ];
 209	int err;
 210
 211	if (p->name[0]) {
 212		if (!dev_valid_name(p->name))
 213			goto failed;
 214		strscpy(name, p->name, IFNAMSIZ);
 215	} else {
 216		sprintf(name, "ip6_vti%%d");
 217	}
 218
 219	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
 220	if (!dev)
 221		goto failed;
 222
 223	dev_net_set(dev, net);
 224
 225	t = netdev_priv(dev);
 226	t->parms = *p;
 227	t->net = dev_net(dev);
 228
 229	err = vti6_tnl_create2(dev);
 230	if (err < 0)
 231		goto failed_free;
 232
 233	return t;
 234
 235failed_free:
 236	free_netdev(dev);
 237failed:
 238	return NULL;
 239}
 240
 241/**
 242 * vti6_locate - find or create tunnel matching given parameters
 243 *   @net: network namespace
 244 *   @p: tunnel parameters
 245 *   @create: != 0 if allowed to create new tunnel if no match found
 246 *
 247 * Description:
 248 *   vti6_locate() first tries to locate an existing tunnel
 249 *   based on @parms. If this is unsuccessful, but @create is set a new
 250 *   tunnel device is created and registered for use.
 251 *
 252 * Return:
 253 *   matching tunnel or NULL
 254 **/
 255static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
 256				   int create)
 257{
 258	const struct in6_addr *remote = &p->raddr;
 259	const struct in6_addr *local = &p->laddr;
 260	struct ip6_tnl __rcu **tp;
 261	struct ip6_tnl *t;
 262	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 263
 264	for (tp = vti6_tnl_bucket(ip6n, p);
 265	     (t = rtnl_dereference(*tp)) != NULL;
 266	     tp = &t->next) {
 267		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 268		    ipv6_addr_equal(remote, &t->parms.raddr)) {
 269			if (create)
 270				return NULL;
 271
 272			return t;
 273		}
 274	}
 275	if (!create)
 276		return NULL;
 277	return vti6_tnl_create(net, p);
 278}
 279
 280/**
 281 * vti6_dev_uninit - tunnel device uninitializer
 282 *   @dev: the device to be destroyed
 283 *
 284 * Description:
 285 *   vti6_dev_uninit() removes tunnel from its list
 286 **/
 287static void vti6_dev_uninit(struct net_device *dev)
 288{
 289	struct ip6_tnl *t = netdev_priv(dev);
 290	struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
 291
 292	if (dev == ip6n->fb_tnl_dev)
 293		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 294	else
 295		vti6_tnl_unlink(ip6n, t);
 296	netdev_put(dev, &t->dev_tracker);
 297}
 298
 299static int vti6_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi,
 300			    int encap_type)
 301{
 302	struct ip6_tnl *t;
 303	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 304
 305	rcu_read_lock();
 306	t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
 307	if (t) {
 308		if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
 309			rcu_read_unlock();
 310			goto discard;
 311		}
 312
 313		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 314			rcu_read_unlock();
 315			goto discard;
 316		}
 317
 318		ipv6h = ipv6_hdr(skb);
 319		if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
 320			DEV_STATS_INC(t->dev, rx_dropped);
 321			rcu_read_unlock();
 322			goto discard;
 323		}
 324
 
 
 325		rcu_read_unlock();
 326
 327		XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
 328		XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
 329		XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
 330		return xfrm_input(skb, nexthdr, spi, encap_type);
 331	}
 332	rcu_read_unlock();
 333	return -EINVAL;
 334discard:
 335	kfree_skb(skb);
 336	return 0;
 337}
 338
 339static int vti6_rcv(struct sk_buff *skb)
 340{
 341	int nexthdr = skb_network_header(skb)[IP6CB(skb)->nhoff];
 342
 343	return vti6_input_proto(skb, nexthdr, 0, 0);
 344}
 345
 346static int vti6_rcv_cb(struct sk_buff *skb, int err)
 347{
 348	unsigned short family;
 349	struct net_device *dev;
 
 350	struct xfrm_state *x;
 351	const struct xfrm_mode *inner_mode;
 352	struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
 353	u32 orig_mark = skb->mark;
 354	int ret;
 355
 356	if (!t)
 357		return 1;
 358
 359	dev = t->dev;
 360
 361	if (err) {
 362		DEV_STATS_INC(dev, rx_errors);
 363		DEV_STATS_INC(dev, rx_dropped);
 364
 365		return 0;
 366	}
 367
 368	x = xfrm_input_state(skb);
 369
 370	inner_mode = &x->inner_mode;
 371
 372	if (x->sel.family == AF_UNSPEC) {
 373		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 374		if (inner_mode == NULL) {
 375			XFRM_INC_STATS(dev_net(skb->dev),
 376				       LINUX_MIB_XFRMINSTATEMODEERROR);
 377			return -EINVAL;
 378		}
 379	}
 380
 381	family = inner_mode->family;
 382
 383	skb->mark = be32_to_cpu(t->parms.i_key);
 384	ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
 385	skb->mark = orig_mark;
 386
 387	if (!ret)
 388		return -EPERM;
 389
 390	skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
 391	skb->dev = dev;
 392	dev_sw_netstats_rx_add(dev, skb->len);
 
 
 
 
 
 393
 394	return 0;
 395}
 396
 397/**
 398 * vti6_addr_conflict - compare packet addresses to tunnel's own
 399 *   @t: the outgoing tunnel device
 400 *   @hdr: IPv6 header from the incoming packet
 401 *
 402 * Description:
 403 *   Avoid trivial tunneling loop by checking that tunnel exit-point
 404 *   doesn't match source of incoming packet.
 405 *
 406 * Return:
 407 *   1 if conflict,
 408 *   0 else
 409 **/
 410static inline bool
 411vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 412{
 413	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 414}
 415
 416static bool vti6_state_check(const struct xfrm_state *x,
 417			     const struct in6_addr *dst,
 418			     const struct in6_addr *src)
 419{
 420	xfrm_address_t *daddr = (xfrm_address_t *)dst;
 421	xfrm_address_t *saddr = (xfrm_address_t *)src;
 422
 423	/* if there is no transform then this tunnel is not functional.
 424	 * Or if the xfrm is not mode tunnel.
 425	 */
 426	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
 427	    x->props.family != AF_INET6)
 428		return false;
 429
 430	if (ipv6_addr_any(dst))
 431		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
 432
 433	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
 434		return false;
 435
 436	return true;
 437}
 438
 439/**
 440 * vti6_xmit - send a packet
 441 *   @skb: the outgoing socket buffer
 442 *   @dev: the outgoing tunnel device
 443 *   @fl: the flow informations for the xfrm_lookup
 444 **/
 445static int
 446vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 447{
 448	struct ip6_tnl *t = netdev_priv(dev);
 
 449	struct dst_entry *dst = skb_dst(skb);
 450	struct net_device *tdev;
 451	struct xfrm_state *x;
 452	int pkt_len = skb->len;
 453	int err = -1;
 454	int mtu;
 455
 456	if (!dst) {
 457		switch (skb->protocol) {
 458		case htons(ETH_P_IP): {
 459			struct rtable *rt;
 460
 461			fl->u.ip4.flowi4_oif = dev->ifindex;
 462			fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
 463			rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4);
 464			if (IS_ERR(rt))
 465				goto tx_err_link_failure;
 466			dst = &rt->dst;
 467			skb_dst_set(skb, dst);
 468			break;
 469		}
 470		case htons(ETH_P_IPV6):
 471			fl->u.ip6.flowi6_oif = dev->ifindex;
 472			fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
 473			dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6);
 474			if (dst->error) {
 475				dst_release(dst);
 476				dst = NULL;
 477				goto tx_err_link_failure;
 478			}
 479			skb_dst_set(skb, dst);
 480			break;
 481		default:
 482			goto tx_err_link_failure;
 483		}
 484	}
 485
 486	dst_hold(dst);
 487	dst = xfrm_lookup_route(t->net, dst, fl, NULL, 0);
 488	if (IS_ERR(dst)) {
 489		err = PTR_ERR(dst);
 490		dst = NULL;
 491		goto tx_err_link_failure;
 492	}
 493
 494	if (dst->flags & DST_XFRM_QUEUE)
 495		goto xmit;
 496
 497	x = dst->xfrm;
 498	if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
 499		goto tx_err_link_failure;
 500
 501	if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
 502			      (const struct in6_addr *)&x->id.daddr))
 503		goto tx_err_link_failure;
 504
 505	tdev = dst->dev;
 506
 507	if (tdev == dev) {
 508		DEV_STATS_INC(dev, collisions);
 509		net_warn_ratelimited("%s: Local routing loop detected!\n",
 510				     t->parms.name);
 511		goto tx_err_dst_release;
 512	}
 513
 
 
 
 
 514	mtu = dst_mtu(dst);
 515	if (skb->len > mtu) {
 516		skb_dst_update_pmtu_no_confirm(skb, mtu);
 517
 518		if (skb->protocol == htons(ETH_P_IPV6)) {
 519			if (mtu < IPV6_MIN_MTU)
 520				mtu = IPV6_MIN_MTU;
 
 
 521
 522			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 523		} else {
 524			if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
 525				goto xmit;
 526			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 527				      htonl(mtu));
 528		}
 529
 530		err = -EMSGSIZE;
 531		goto tx_err_dst_release;
 532	}
 533
 534xmit:
 535	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
 536	skb_dst_set(skb, dst);
 537	skb->dev = skb_dst(skb)->dev;
 538
 539	err = dst_output(t->net, skb->sk, skb);
 540	if (net_xmit_eval(err) == 0)
 541		err = pkt_len;
 542	iptunnel_xmit_stats(dev, err);
 
 
 
 
 543
 544	return 0;
 545tx_err_link_failure:
 546	DEV_STATS_INC(dev, tx_carrier_errors);
 547	dst_link_failure(skb);
 548tx_err_dst_release:
 549	dst_release(dst);
 550	return err;
 551}
 552
 553static netdev_tx_t
 554vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
 555{
 556	struct ip6_tnl *t = netdev_priv(dev);
 
 
 557	struct flowi fl;
 558	int ret;
 559
 560	if (!pskb_inet_may_pull(skb))
 561		goto tx_err;
 562
 563	memset(&fl, 0, sizeof(fl));
 564
 565	switch (skb->protocol) {
 566	case htons(ETH_P_IPV6):
 
 
 567		if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
 568		    vti6_addr_conflict(t, ipv6_hdr(skb)))
 569			goto tx_err;
 570
 
 571		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
 572		xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET6);
 573		break;
 574	case htons(ETH_P_IP):
 
 575		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 576		xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET);
 577		break;
 578	default:
 579		goto tx_err;
 580	}
 581
 582	/* override mark with tunnel output key */
 583	fl.flowi_mark = be32_to_cpu(t->parms.o_key);
 584
 585	ret = vti6_xmit(skb, dev, &fl);
 586	if (ret < 0)
 587		goto tx_err;
 588
 589	return NETDEV_TX_OK;
 590
 591tx_err:
 592	DEV_STATS_INC(dev, tx_errors);
 593	DEV_STATS_INC(dev, tx_dropped);
 594	kfree_skb(skb);
 595	return NETDEV_TX_OK;
 596}
 597
 598static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 599		    u8 type, u8 code, int offset, __be32 info)
 600{
 601	__be32 spi;
 602	__u32 mark;
 603	struct xfrm_state *x;
 604	struct ip6_tnl *t;
 605	struct ip_esp_hdr *esph;
 606	struct ip_auth_hdr *ah;
 607	struct ip_comp_hdr *ipch;
 608	struct net *net = dev_net(skb->dev);
 609	const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
 610	int protocol = iph->nexthdr;
 611
 612	t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
 613	if (!t)
 614		return -1;
 615
 616	mark = be32_to_cpu(t->parms.o_key);
 617
 618	switch (protocol) {
 619	case IPPROTO_ESP:
 620		esph = (struct ip_esp_hdr *)(skb->data + offset);
 621		spi = esph->spi;
 622		break;
 623	case IPPROTO_AH:
 624		ah = (struct ip_auth_hdr *)(skb->data + offset);
 625		spi = ah->spi;
 626		break;
 627	case IPPROTO_COMP:
 628		ipch = (struct ip_comp_hdr *)(skb->data + offset);
 629		spi = htonl(ntohs(ipch->cpi));
 630		break;
 631	default:
 632		return 0;
 633	}
 634
 635	if (type != ICMPV6_PKT_TOOBIG &&
 636	    type != NDISC_REDIRECT)
 637		return 0;
 638
 639	x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
 640			      spi, protocol, AF_INET6);
 641	if (!x)
 642		return 0;
 643
 644	if (type == NDISC_REDIRECT)
 645		ip6_redirect(skb, net, skb->dev->ifindex, 0,
 646			     sock_net_uid(net, NULL));
 647	else
 648		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
 649	xfrm_state_put(x);
 650
 651	return 0;
 652}
 653
 654static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu)
 655{
 656	struct net_device *dev = t->dev;
 657	struct __ip6_tnl_parm *p = &t->parms;
 658	struct net_device *tdev = NULL;
 659	int mtu;
 660
 661	__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
 662	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
 663
 664	p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
 665		      IP6_TNL_F_CAP_PER_PACKET);
 666	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
 667
 668	if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
 669		dev->flags |= IFF_POINTOPOINT;
 670	else
 671		dev->flags &= ~IFF_POINTOPOINT;
 672
 673	if (keep_mtu && dev->mtu) {
 674		dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu);
 675		return;
 676	}
 677
 678	if (p->flags & IP6_TNL_F_CAP_XMIT) {
 679		int strict = (ipv6_addr_type(&p->raddr) &
 680			      (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
 681		struct rt6_info *rt = rt6_lookup(t->net,
 682						 &p->raddr, &p->laddr,
 683						 p->link, NULL, strict);
 684
 685		if (rt)
 686			tdev = rt->dst.dev;
 687		ip6_rt_put(rt);
 688	}
 689
 690	if (!tdev && p->link)
 691		tdev = __dev_get_by_index(t->net, p->link);
 692
 693	if (tdev)
 694		mtu = tdev->mtu - sizeof(struct ipv6hdr);
 695	else
 696		mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr);
 697
 698	dev->mtu = max_t(int, mtu, IPV4_MIN_MTU);
 699}
 700
 701/**
 702 * vti6_tnl_change - update the tunnel parameters
 703 *   @t: tunnel to be changed
 704 *   @p: tunnel configuration parameters
 705 *   @keep_mtu: MTU was set from userspace, don't re-compute it
 706 *
 707 * Description:
 708 *   vti6_tnl_change() updates the tunnel parameters
 709 **/
 710static int
 711vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
 712		bool keep_mtu)
 713{
 714	t->parms.laddr = p->laddr;
 715	t->parms.raddr = p->raddr;
 716	t->parms.link = p->link;
 717	t->parms.i_key = p->i_key;
 718	t->parms.o_key = p->o_key;
 719	t->parms.proto = p->proto;
 720	t->parms.fwmark = p->fwmark;
 721	dst_cache_reset(&t->dst_cache);
 722	vti6_link_config(t, keep_mtu);
 723	return 0;
 724}
 725
 726static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p,
 727		       bool keep_mtu)
 728{
 729	struct net *net = dev_net(t->dev);
 730	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 731	int err;
 732
 733	vti6_tnl_unlink(ip6n, t);
 734	synchronize_net();
 735	err = vti6_tnl_change(t, p, keep_mtu);
 736	vti6_tnl_link(ip6n, t);
 737	netdev_state_change(t->dev);
 738	return err;
 739}
 740
 741static void
 742vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
 743{
 744	p->laddr = u->laddr;
 745	p->raddr = u->raddr;
 746	p->link = u->link;
 747	p->i_key = u->i_key;
 748	p->o_key = u->o_key;
 749	p->proto = u->proto;
 750
 751	memcpy(p->name, u->name, sizeof(u->name));
 752}
 753
 754static void
 755vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
 756{
 757	u->laddr = p->laddr;
 758	u->raddr = p->raddr;
 759	u->link = p->link;
 760	u->i_key = p->i_key;
 761	u->o_key = p->o_key;
 762	if (u->i_key)
 763		u->i_flags |= GRE_KEY;
 764	if (u->o_key)
 765		u->o_flags |= GRE_KEY;
 766	u->proto = p->proto;
 767
 768	memcpy(u->name, p->name, sizeof(u->name));
 769}
 770
 771/**
 772 * vti6_siocdevprivate - configure vti6 tunnels from userspace
 773 *   @dev: virtual device associated with tunnel
 774 *   @ifr: unused
 775 *   @data: parameters passed from userspace
 776 *   @cmd: command to be performed
 777 *
 778 * Description:
 779 *   vti6_siocdevprivate() is used for managing vti6 tunnels
 780 *   from userspace.
 781 *
 782 *   The possible commands are the following:
 783 *     %SIOCGETTUNNEL: get tunnel parameters for device
 784 *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
 785 *     %SIOCCHGTUNNEL: change tunnel parameters to those given
 786 *     %SIOCDELTUNNEL: delete tunnel
 787 *
 788 *   The fallback device "ip6_vti0", created during module
 789 *   initialization, can be used for creating other tunnel devices.
 790 *
 791 * Return:
 792 *   0 on success,
 793 *   %-EFAULT if unable to copy data to or from userspace,
 794 *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
 795 *   %-EINVAL if passed tunnel parameters are invalid,
 796 *   %-EEXIST if changing a tunnel's parameters would cause a conflict
 797 *   %-ENODEV if attempting to change or delete a nonexisting device
 798 **/
 799static int
 800vti6_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __user *data, int cmd)
 801{
 802	int err = 0;
 803	struct ip6_tnl_parm2 p;
 804	struct __ip6_tnl_parm p1;
 805	struct ip6_tnl *t = NULL;
 806	struct net *net = dev_net(dev);
 807	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 808
 809	memset(&p1, 0, sizeof(p1));
 810
 811	switch (cmd) {
 812	case SIOCGETTUNNEL:
 813		if (dev == ip6n->fb_tnl_dev) {
 814			if (copy_from_user(&p, data, sizeof(p))) {
 815				err = -EFAULT;
 816				break;
 817			}
 818			vti6_parm_from_user(&p1, &p);
 819			t = vti6_locate(net, &p1, 0);
 820		} else {
 821			memset(&p, 0, sizeof(p));
 822		}
 823		if (!t)
 824			t = netdev_priv(dev);
 825		vti6_parm_to_user(&p, &t->parms);
 826		if (copy_to_user(data, &p, sizeof(p)))
 827			err = -EFAULT;
 828		break;
 829	case SIOCADDTUNNEL:
 830	case SIOCCHGTUNNEL:
 831		err = -EPERM;
 832		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 833			break;
 834		err = -EFAULT;
 835		if (copy_from_user(&p, data, sizeof(p)))
 836			break;
 837		err = -EINVAL;
 838		if (p.proto != IPPROTO_IPV6  && p.proto != 0)
 839			break;
 840		vti6_parm_from_user(&p1, &p);
 841		t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
 842		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
 843			if (t) {
 844				if (t->dev != dev) {
 845					err = -EEXIST;
 846					break;
 847				}
 848			} else
 849				t = netdev_priv(dev);
 850
 851			err = vti6_update(t, &p1, false);
 852		}
 853		if (t) {
 854			err = 0;
 855			vti6_parm_to_user(&p, &t->parms);
 856			if (copy_to_user(data, &p, sizeof(p)))
 857				err = -EFAULT;
 858
 859		} else
 860			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
 861		break;
 862	case SIOCDELTUNNEL:
 863		err = -EPERM;
 864		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 865			break;
 866
 867		if (dev == ip6n->fb_tnl_dev) {
 868			err = -EFAULT;
 869			if (copy_from_user(&p, data, sizeof(p)))
 870				break;
 871			err = -ENOENT;
 872			vti6_parm_from_user(&p1, &p);
 873			t = vti6_locate(net, &p1, 0);
 874			if (!t)
 875				break;
 876			err = -EPERM;
 877			if (t->dev == ip6n->fb_tnl_dev)
 878				break;
 879			dev = t->dev;
 880		}
 881		err = 0;
 882		unregister_netdevice(dev);
 883		break;
 884	default:
 885		err = -EINVAL;
 886	}
 887	return err;
 888}
 889
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 890static const struct net_device_ops vti6_netdev_ops = {
 891	.ndo_init	= vti6_dev_init,
 892	.ndo_uninit	= vti6_dev_uninit,
 893	.ndo_start_xmit = vti6_tnl_xmit,
 894	.ndo_siocdevprivate = vti6_siocdevprivate,
 895	.ndo_get_stats64 = dev_get_tstats64,
 
 896	.ndo_get_iflink = ip6_tnl_get_iflink,
 897};
 898
 899/**
 900 * vti6_dev_setup - setup virtual tunnel device
 901 *   @dev: virtual device associated with tunnel
 902 *
 903 * Description:
 904 *   Initialize function pointers and device parameters
 905 **/
 906static void vti6_dev_setup(struct net_device *dev)
 907{
 908	dev->netdev_ops = &vti6_netdev_ops;
 909	dev->header_ops = &ip_tunnel_header_ops;
 910	dev->needs_free_netdev = true;
 911	dev->priv_destructor = vti6_dev_free;
 912
 913	dev->type = ARPHRD_TUNNEL6;
 914	dev->min_mtu = IPV4_MIN_MTU;
 915	dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr);
 916	dev->flags |= IFF_NOARP;
 917	dev->addr_len = sizeof(struct in6_addr);
 918	netif_keep_dst(dev);
 919	/* This perm addr will be used as interface identifier by IPv6 */
 920	dev->addr_assign_type = NET_ADDR_RANDOM;
 921	eth_random_addr(dev->perm_addr);
 922}
 923
 924/**
 925 * vti6_dev_init_gen - general initializer for all tunnel devices
 926 *   @dev: virtual device associated with tunnel
 927 **/
 928static inline int vti6_dev_init_gen(struct net_device *dev)
 929{
 930	struct ip6_tnl *t = netdev_priv(dev);
 931
 932	t->dev = dev;
 933	t->net = dev_net(dev);
 934	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 935	if (!dev->tstats)
 936		return -ENOMEM;
 937	netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
 938	return 0;
 939}
 940
 941/**
 942 * vti6_dev_init - initializer for all non fallback tunnel devices
 943 *   @dev: virtual device associated with tunnel
 944 **/
 945static int vti6_dev_init(struct net_device *dev)
 946{
 947	struct ip6_tnl *t = netdev_priv(dev);
 948	int err = vti6_dev_init_gen(dev);
 949
 950	if (err)
 951		return err;
 952	vti6_link_config(t, true);
 953	return 0;
 954}
 955
 956/**
 957 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
 958 *   @dev: fallback device
 959 *
 960 * Return: 0
 961 **/
 962static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
 963{
 964	struct ip6_tnl *t = netdev_priv(dev);
 965	struct net *net = dev_net(dev);
 966	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 967
 968	t->parms.proto = IPPROTO_IPV6;
 
 969
 970	rcu_assign_pointer(ip6n->tnls_wc[0], t);
 971	return 0;
 972}
 973
 974static int vti6_validate(struct nlattr *tb[], struct nlattr *data[],
 975			 struct netlink_ext_ack *extack)
 976{
 977	return 0;
 978}
 979
 980static void vti6_netlink_parms(struct nlattr *data[],
 981			       struct __ip6_tnl_parm *parms)
 982{
 983	memset(parms, 0, sizeof(*parms));
 984
 985	if (!data)
 986		return;
 987
 988	if (data[IFLA_VTI_LINK])
 989		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
 990
 991	if (data[IFLA_VTI_LOCAL])
 992		parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
 993
 994	if (data[IFLA_VTI_REMOTE])
 995		parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
 996
 997	if (data[IFLA_VTI_IKEY])
 998		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
 999
1000	if (data[IFLA_VTI_OKEY])
1001		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
1002
1003	if (data[IFLA_VTI_FWMARK])
1004		parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
1005}
1006
1007static int vti6_newlink(struct net *src_net, struct net_device *dev,
1008			struct nlattr *tb[], struct nlattr *data[],
1009			struct netlink_ext_ack *extack)
1010{
1011	struct net *net = dev_net(dev);
1012	struct ip6_tnl *nt;
1013
1014	nt = netdev_priv(dev);
1015	vti6_netlink_parms(data, &nt->parms);
1016
1017	nt->parms.proto = IPPROTO_IPV6;
1018
1019	if (vti6_locate(net, &nt->parms, 0))
1020		return -EEXIST;
1021
1022	return vti6_tnl_create2(dev);
1023}
1024
1025static void vti6_dellink(struct net_device *dev, struct list_head *head)
1026{
1027	struct net *net = dev_net(dev);
1028	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1029
1030	if (dev != ip6n->fb_tnl_dev)
1031		unregister_netdevice_queue(dev, head);
1032}
1033
1034static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
1035			   struct nlattr *data[],
1036			   struct netlink_ext_ack *extack)
1037{
1038	struct ip6_tnl *t;
1039	struct __ip6_tnl_parm p;
1040	struct net *net = dev_net(dev);
1041	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1042
1043	if (dev == ip6n->fb_tnl_dev)
1044		return -EINVAL;
1045
1046	vti6_netlink_parms(data, &p);
1047
1048	t = vti6_locate(net, &p, 0);
1049
1050	if (t) {
1051		if (t->dev != dev)
1052			return -EEXIST;
1053	} else
1054		t = netdev_priv(dev);
1055
1056	return vti6_update(t, &p, tb && tb[IFLA_MTU]);
1057}
1058
1059static size_t vti6_get_size(const struct net_device *dev)
1060{
1061	return
1062		/* IFLA_VTI_LINK */
1063		nla_total_size(4) +
1064		/* IFLA_VTI_LOCAL */
1065		nla_total_size(sizeof(struct in6_addr)) +
1066		/* IFLA_VTI_REMOTE */
1067		nla_total_size(sizeof(struct in6_addr)) +
1068		/* IFLA_VTI_IKEY */
1069		nla_total_size(4) +
1070		/* IFLA_VTI_OKEY */
1071		nla_total_size(4) +
1072		/* IFLA_VTI_FWMARK */
1073		nla_total_size(4) +
1074		0;
1075}
1076
1077static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1078{
1079	struct ip6_tnl *tunnel = netdev_priv(dev);
1080	struct __ip6_tnl_parm *parm = &tunnel->parms;
1081
1082	if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
1083	    nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
1084	    nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
1085	    nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
1086	    nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key) ||
1087	    nla_put_u32(skb, IFLA_VTI_FWMARK, parm->fwmark))
1088		goto nla_put_failure;
1089	return 0;
1090
1091nla_put_failure:
1092	return -EMSGSIZE;
1093}
1094
1095static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
1096	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
1097	[IFLA_VTI_LOCAL]	= { .len = sizeof(struct in6_addr) },
1098	[IFLA_VTI_REMOTE]	= { .len = sizeof(struct in6_addr) },
1099	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
1100	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
1101	[IFLA_VTI_FWMARK]	= { .type = NLA_U32 },
1102};
1103
1104static struct rtnl_link_ops vti6_link_ops __read_mostly = {
1105	.kind		= "vti6",
1106	.maxtype	= IFLA_VTI_MAX,
1107	.policy		= vti6_policy,
1108	.priv_size	= sizeof(struct ip6_tnl),
1109	.setup		= vti6_dev_setup,
1110	.validate	= vti6_validate,
1111	.newlink	= vti6_newlink,
1112	.dellink	= vti6_dellink,
1113	.changelink	= vti6_changelink,
1114	.get_size	= vti6_get_size,
1115	.fill_info	= vti6_fill_info,
1116	.get_link_net	= ip6_tnl_get_link_net,
1117};
1118
1119static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n,
1120					    struct list_head *list)
1121{
1122	int h;
1123	struct ip6_tnl *t;
 
1124
1125	for (h = 0; h < IP6_VTI_HASH_SIZE; h++) {
1126		t = rtnl_dereference(ip6n->tnls_r_l[h]);
1127		while (t) {
1128			unregister_netdevice_queue(t->dev, list);
1129			t = rtnl_dereference(t->next);
1130		}
1131	}
1132
1133	t = rtnl_dereference(ip6n->tnls_wc[0]);
1134	if (t)
1135		unregister_netdevice_queue(t->dev, list);
1136}
1137
1138static int __net_init vti6_init_net(struct net *net)
1139{
1140	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1141	struct ip6_tnl *t = NULL;
1142	int err;
1143
1144	ip6n->tnls[0] = ip6n->tnls_wc;
1145	ip6n->tnls[1] = ip6n->tnls_r_l;
1146
1147	if (!net_has_fallback_tunnels(net))
1148		return 0;
1149	err = -ENOMEM;
1150	ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1151					NET_NAME_UNKNOWN, vti6_dev_setup);
1152
1153	if (!ip6n->fb_tnl_dev)
1154		goto err_alloc_dev;
1155	dev_net_set(ip6n->fb_tnl_dev, net);
1156	ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
1157
1158	err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1159	if (err < 0)
1160		goto err_register;
1161
1162	err = register_netdev(ip6n->fb_tnl_dev);
1163	if (err < 0)
1164		goto err_register;
1165
1166	t = netdev_priv(ip6n->fb_tnl_dev);
1167
1168	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1169	return 0;
1170
1171err_register:
1172	free_netdev(ip6n->fb_tnl_dev);
1173err_alloc_dev:
1174	return err;
1175}
1176
1177static void __net_exit vti6_exit_batch_net(struct list_head *net_list)
1178{
1179	struct vti6_net *ip6n;
1180	struct net *net;
1181	LIST_HEAD(list);
1182
1183	rtnl_lock();
1184	list_for_each_entry(net, net_list, exit_list) {
1185		ip6n = net_generic(net, vti6_net_id);
1186		vti6_destroy_tunnels(ip6n, &list);
1187	}
1188	unregister_netdevice_many(&list);
1189	rtnl_unlock();
1190}
1191
1192static struct pernet_operations vti6_net_ops = {
1193	.init = vti6_init_net,
1194	.exit_batch = vti6_exit_batch_net,
1195	.id   = &vti6_net_id,
1196	.size = sizeof(struct vti6_net),
1197};
1198
1199static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1200	.handler	=	vti6_rcv,
1201	.input_handler	=	vti6_input_proto,
1202	.cb_handler	=	vti6_rcv_cb,
1203	.err_handler	=	vti6_err,
1204	.priority	=	100,
1205};
1206
1207static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1208	.handler	=	vti6_rcv,
1209	.input_handler	=	vti6_input_proto,
1210	.cb_handler	=	vti6_rcv_cb,
1211	.err_handler	=	vti6_err,
1212	.priority	=	100,
1213};
1214
1215static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1216	.handler	=	vti6_rcv,
1217	.input_handler	=	vti6_input_proto,
1218	.cb_handler	=	vti6_rcv_cb,
1219	.err_handler	=	vti6_err,
1220	.priority	=	100,
1221};
1222
1223#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1224static int vti6_rcv_tunnel(struct sk_buff *skb)
1225{
1226	const xfrm_address_t *saddr;
1227	__be32 spi;
1228
1229	saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr;
1230	spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr);
1231
1232	return vti6_input_proto(skb, IPPROTO_IPV6, spi, 0);
1233}
1234
1235static struct xfrm6_tunnel vti_ipv6_handler __read_mostly = {
1236	.handler	=	vti6_rcv_tunnel,
1237	.cb_handler	=	vti6_rcv_cb,
1238	.err_handler	=	vti6_err,
1239	.priority	=	0,
1240};
1241
1242static struct xfrm6_tunnel vti_ip6ip_handler __read_mostly = {
1243	.handler	=	vti6_rcv_tunnel,
1244	.cb_handler	=	vti6_rcv_cb,
1245	.err_handler	=	vti6_err,
1246	.priority	=	0,
1247};
1248#endif
1249
1250/**
1251 * vti6_tunnel_init - register protocol and reserve needed resources
1252 *
1253 * Return: 0 on success
1254 **/
1255static int __init vti6_tunnel_init(void)
1256{
1257	const char *msg;
1258	int err;
1259
1260	msg = "tunnel device";
1261	err = register_pernet_device(&vti6_net_ops);
1262	if (err < 0)
1263		goto pernet_dev_failed;
1264
1265	msg = "tunnel protocols";
1266	err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1267	if (err < 0)
1268		goto xfrm_proto_esp_failed;
1269	err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1270	if (err < 0)
1271		goto xfrm_proto_ah_failed;
1272	err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1273	if (err < 0)
1274		goto xfrm_proto_comp_failed;
1275#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1276	msg = "ipv6 tunnel";
1277	err = xfrm6_tunnel_register(&vti_ipv6_handler, AF_INET6);
1278	if (err < 0)
1279		goto vti_tunnel_ipv6_failed;
1280	err = xfrm6_tunnel_register(&vti_ip6ip_handler, AF_INET);
1281	if (err < 0)
1282		goto vti_tunnel_ip6ip_failed;
1283#endif
1284
1285	msg = "netlink interface";
1286	err = rtnl_link_register(&vti6_link_ops);
1287	if (err < 0)
1288		goto rtnl_link_failed;
1289
1290	return 0;
1291
1292rtnl_link_failed:
1293#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1294	err = xfrm6_tunnel_deregister(&vti_ip6ip_handler, AF_INET);
1295vti_tunnel_ip6ip_failed:
1296	err = xfrm6_tunnel_deregister(&vti_ipv6_handler, AF_INET6);
1297vti_tunnel_ipv6_failed:
1298#endif
1299	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1300xfrm_proto_comp_failed:
1301	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1302xfrm_proto_ah_failed:
1303	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1304xfrm_proto_esp_failed:
1305	unregister_pernet_device(&vti6_net_ops);
1306pernet_dev_failed:
1307	pr_err("vti6 init: failed to register %s\n", msg);
1308	return err;
1309}
1310
1311/**
1312 * vti6_tunnel_cleanup - free resources and unregister protocol
1313 **/
1314static void __exit vti6_tunnel_cleanup(void)
1315{
1316	rtnl_link_unregister(&vti6_link_ops);
1317#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1318	xfrm6_tunnel_deregister(&vti_ip6ip_handler, AF_INET);
1319	xfrm6_tunnel_deregister(&vti_ipv6_handler, AF_INET6);
1320#endif
1321	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1322	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1323	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1324	unregister_pernet_device(&vti6_net_ops);
1325}
1326
1327module_init(vti6_tunnel_init);
1328module_exit(vti6_tunnel_cleanup);
1329MODULE_LICENSE("GPL");
1330MODULE_ALIAS_RTNL_LINK("vti6");
1331MODULE_ALIAS_NETDEV("ip6_vti0");
1332MODULE_AUTHOR("Steffen Klassert");
1333MODULE_DESCRIPTION("IPv6 virtual tunnel interface");