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Note: File does not exist in v3.5.6.
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	GRE over IPv6 protocol decoder.
   4 *
   5 *	Authors: Dmitry Kozlov (xeb@mail.ru)
   6 */
   7
   8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10#include <linux/capability.h>
  11#include <linux/module.h>
  12#include <linux/types.h>
  13#include <linux/kernel.h>
  14#include <linux/slab.h>
  15#include <linux/uaccess.h>
  16#include <linux/skbuff.h>
  17#include <linux/netdevice.h>
  18#include <linux/in.h>
  19#include <linux/tcp.h>
  20#include <linux/udp.h>
  21#include <linux/if_arp.h>
  22#include <linux/init.h>
  23#include <linux/in6.h>
  24#include <linux/inetdevice.h>
  25#include <linux/igmp.h>
  26#include <linux/netfilter_ipv4.h>
  27#include <linux/etherdevice.h>
  28#include <linux/if_ether.h>
  29#include <linux/hash.h>
  30#include <linux/if_tunnel.h>
  31#include <linux/ip6_tunnel.h>
  32
  33#include <net/sock.h>
  34#include <net/ip.h>
  35#include <net/ip_tunnels.h>
  36#include <net/icmp.h>
  37#include <net/protocol.h>
  38#include <net/addrconf.h>
  39#include <net/arp.h>
  40#include <net/checksum.h>
  41#include <net/dsfield.h>
  42#include <net/inet_ecn.h>
  43#include <net/xfrm.h>
  44#include <net/net_namespace.h>
  45#include <net/netns/generic.h>
  46#include <net/rtnetlink.h>
  47
  48#include <net/ipv6.h>
  49#include <net/ip6_fib.h>
  50#include <net/ip6_route.h>
  51#include <net/ip6_tunnel.h>
  52#include <net/gre.h>
  53#include <net/erspan.h>
  54#include <net/dst_metadata.h>
  55
  56
  57static bool log_ecn_error = true;
  58module_param(log_ecn_error, bool, 0644);
  59MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  60
  61#define IP6_GRE_HASH_SIZE_SHIFT  5
  62#define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
  63
  64static unsigned int ip6gre_net_id __read_mostly;
  65struct ip6gre_net {
  66	struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
  67
  68	struct ip6_tnl __rcu *collect_md_tun;
  69	struct ip6_tnl __rcu *collect_md_tun_erspan;
  70	struct net_device *fb_tunnel_dev;
  71};
  72
  73static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
  74static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
  75static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
  76static int ip6gre_tunnel_init(struct net_device *dev);
  77static void ip6gre_tunnel_setup(struct net_device *dev);
  78static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
  79static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  80static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
  81
  82/* Tunnel hash table */
  83
  84/*
  85   4 hash tables:
  86
  87   3: (remote,local)
  88   2: (remote,*)
  89   1: (*,local)
  90   0: (*,*)
  91
  92   We require exact key match i.e. if a key is present in packet
  93   it will match only tunnel with the same key; if it is not present,
  94   it will match only keyless tunnel.
  95
  96   All keysless packets, if not matched configured keyless tunnels
  97   will match fallback tunnel.
  98 */
  99
 100#define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
 101static u32 HASH_ADDR(const struct in6_addr *addr)
 102{
 103	u32 hash = ipv6_addr_hash(addr);
 104
 105	return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
 106}
 107
 108#define tunnels_r_l	tunnels[3]
 109#define tunnels_r	tunnels[2]
 110#define tunnels_l	tunnels[1]
 111#define tunnels_wc	tunnels[0]
 112
 113/* Given src, dst and key, find appropriate for input tunnel. */
 114
 115static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
 116		const struct in6_addr *remote, const struct in6_addr *local,
 117		__be32 key, __be16 gre_proto)
 118{
 119	struct net *net = dev_net(dev);
 120	int link = dev->ifindex;
 121	unsigned int h0 = HASH_ADDR(remote);
 122	unsigned int h1 = HASH_KEY(key);
 123	struct ip6_tnl *t, *cand = NULL;
 124	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 125	int dev_type = (gre_proto == htons(ETH_P_TEB) ||
 126			gre_proto == htons(ETH_P_ERSPAN) ||
 127			gre_proto == htons(ETH_P_ERSPAN2)) ?
 128		       ARPHRD_ETHER : ARPHRD_IP6GRE;
 129	int score, cand_score = 4;
 130	struct net_device *ndev;
 131
 132	for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
 133		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 134		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
 135		    key != t->parms.i_key ||
 136		    !(t->dev->flags & IFF_UP))
 137			continue;
 138
 139		if (t->dev->type != ARPHRD_IP6GRE &&
 140		    t->dev->type != dev_type)
 141			continue;
 142
 143		score = 0;
 144		if (t->parms.link != link)
 145			score |= 1;
 146		if (t->dev->type != dev_type)
 147			score |= 2;
 148		if (score == 0)
 149			return t;
 150
 151		if (score < cand_score) {
 152			cand = t;
 153			cand_score = score;
 154		}
 155	}
 156
 157	for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
 158		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
 159		    key != t->parms.i_key ||
 160		    !(t->dev->flags & IFF_UP))
 161			continue;
 162
 163		if (t->dev->type != ARPHRD_IP6GRE &&
 164		    t->dev->type != dev_type)
 165			continue;
 166
 167		score = 0;
 168		if (t->parms.link != link)
 169			score |= 1;
 170		if (t->dev->type != dev_type)
 171			score |= 2;
 172		if (score == 0)
 173			return t;
 174
 175		if (score < cand_score) {
 176			cand = t;
 177			cand_score = score;
 178		}
 179	}
 180
 181	for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
 182		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
 183			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
 184				 !ipv6_addr_is_multicast(local))) ||
 185		    key != t->parms.i_key ||
 186		    !(t->dev->flags & IFF_UP))
 187			continue;
 188
 189		if (t->dev->type != ARPHRD_IP6GRE &&
 190		    t->dev->type != dev_type)
 191			continue;
 192
 193		score = 0;
 194		if (t->parms.link != link)
 195			score |= 1;
 196		if (t->dev->type != dev_type)
 197			score |= 2;
 198		if (score == 0)
 199			return t;
 200
 201		if (score < cand_score) {
 202			cand = t;
 203			cand_score = score;
 204		}
 205	}
 206
 207	for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
 208		if (t->parms.i_key != key ||
 209		    !(t->dev->flags & IFF_UP))
 210			continue;
 211
 212		if (t->dev->type != ARPHRD_IP6GRE &&
 213		    t->dev->type != dev_type)
 214			continue;
 215
 216		score = 0;
 217		if (t->parms.link != link)
 218			score |= 1;
 219		if (t->dev->type != dev_type)
 220			score |= 2;
 221		if (score == 0)
 222			return t;
 223
 224		if (score < cand_score) {
 225			cand = t;
 226			cand_score = score;
 227		}
 228	}
 229
 230	if (cand)
 231		return cand;
 232
 233	if (gre_proto == htons(ETH_P_ERSPAN) ||
 234	    gre_proto == htons(ETH_P_ERSPAN2))
 235		t = rcu_dereference(ign->collect_md_tun_erspan);
 236	else
 237		t = rcu_dereference(ign->collect_md_tun);
 238
 239	if (t && t->dev->flags & IFF_UP)
 240		return t;
 241
 242	ndev = READ_ONCE(ign->fb_tunnel_dev);
 243	if (ndev && ndev->flags & IFF_UP)
 244		return netdev_priv(ndev);
 245
 246	return NULL;
 247}
 248
 249static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
 250		const struct __ip6_tnl_parm *p)
 251{
 252	const struct in6_addr *remote = &p->raddr;
 253	const struct in6_addr *local = &p->laddr;
 254	unsigned int h = HASH_KEY(p->i_key);
 255	int prio = 0;
 256
 257	if (!ipv6_addr_any(local))
 258		prio |= 1;
 259	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
 260		prio |= 2;
 261		h ^= HASH_ADDR(remote);
 262	}
 263
 264	return &ign->tunnels[prio][h];
 265}
 266
 267static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 268{
 269	if (t->parms.collect_md)
 270		rcu_assign_pointer(ign->collect_md_tun, t);
 271}
 272
 273static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 274{
 275	if (t->parms.collect_md)
 276		rcu_assign_pointer(ign->collect_md_tun_erspan, t);
 277}
 278
 279static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
 280{
 281	if (t->parms.collect_md)
 282		rcu_assign_pointer(ign->collect_md_tun, NULL);
 283}
 284
 285static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
 286				       struct ip6_tnl *t)
 287{
 288	if (t->parms.collect_md)
 289		rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
 290}
 291
 292static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
 293		const struct ip6_tnl *t)
 294{
 295	return __ip6gre_bucket(ign, &t->parms);
 296}
 297
 298static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
 299{
 300	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
 301
 302	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
 303	rcu_assign_pointer(*tp, t);
 304}
 305
 306static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
 307{
 308	struct ip6_tnl __rcu **tp;
 309	struct ip6_tnl *iter;
 310
 311	for (tp = ip6gre_bucket(ign, t);
 312	     (iter = rtnl_dereference(*tp)) != NULL;
 313	     tp = &iter->next) {
 314		if (t == iter) {
 315			rcu_assign_pointer(*tp, t->next);
 316			break;
 317		}
 318	}
 319}
 320
 321static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
 322					   const struct __ip6_tnl_parm *parms,
 323					   int type)
 324{
 325	const struct in6_addr *remote = &parms->raddr;
 326	const struct in6_addr *local = &parms->laddr;
 327	__be32 key = parms->i_key;
 328	int link = parms->link;
 329	struct ip6_tnl *t;
 330	struct ip6_tnl __rcu **tp;
 331	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 332
 333	for (tp = __ip6gre_bucket(ign, parms);
 334	     (t = rtnl_dereference(*tp)) != NULL;
 335	     tp = &t->next)
 336		if (ipv6_addr_equal(local, &t->parms.laddr) &&
 337		    ipv6_addr_equal(remote, &t->parms.raddr) &&
 338		    key == t->parms.i_key &&
 339		    link == t->parms.link &&
 340		    type == t->dev->type)
 341			break;
 342
 343	return t;
 344}
 345
 346static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
 347		const struct __ip6_tnl_parm *parms, int create)
 348{
 349	struct ip6_tnl *t, *nt;
 350	struct net_device *dev;
 351	char name[IFNAMSIZ];
 352	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
 353
 354	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
 355	if (t && create)
 356		return NULL;
 357	if (t || !create)
 358		return t;
 359
 360	if (parms->name[0]) {
 361		if (!dev_valid_name(parms->name))
 362			return NULL;
 363		strscpy(name, parms->name, IFNAMSIZ);
 364	} else {
 365		strcpy(name, "ip6gre%d");
 366	}
 367	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
 368			   ip6gre_tunnel_setup);
 369	if (!dev)
 370		return NULL;
 371
 372	dev_net_set(dev, net);
 373
 374	nt = netdev_priv(dev);
 375	nt->parms = *parms;
 376	dev->rtnl_link_ops = &ip6gre_link_ops;
 377
 378	nt->dev = dev;
 379	nt->net = dev_net(dev);
 380
 381	if (register_netdevice(dev) < 0)
 382		goto failed_free;
 383
 384	ip6gre_tnl_link_config(nt, 1);
 385	ip6gre_tunnel_link(ign, nt);
 386	return nt;
 387
 388failed_free:
 389	free_netdev(dev);
 390	return NULL;
 391}
 392
 393static void ip6erspan_tunnel_uninit(struct net_device *dev)
 394{
 395	struct ip6_tnl *t = netdev_priv(dev);
 396	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
 397
 398	ip6erspan_tunnel_unlink_md(ign, t);
 399	ip6gre_tunnel_unlink(ign, t);
 400	dst_cache_reset(&t->dst_cache);
 401	netdev_put(dev, &t->dev_tracker);
 402}
 403
 404static void ip6gre_tunnel_uninit(struct net_device *dev)
 405{
 406	struct ip6_tnl *t = netdev_priv(dev);
 407	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
 408
 409	ip6gre_tunnel_unlink_md(ign, t);
 410	ip6gre_tunnel_unlink(ign, t);
 411	if (ign->fb_tunnel_dev == dev)
 412		WRITE_ONCE(ign->fb_tunnel_dev, NULL);
 413	dst_cache_reset(&t->dst_cache);
 414	netdev_put(dev, &t->dev_tracker);
 415}
 416
 417
 418static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 419		       u8 type, u8 code, int offset, __be32 info)
 420{
 421	struct net *net = dev_net(skb->dev);
 422	const struct ipv6hdr *ipv6h;
 423	struct tnl_ptk_info tpi;
 424	struct ip6_tnl *t;
 425
 426	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
 427			     offset) < 0)
 428		return -EINVAL;
 429
 430	ipv6h = (const struct ipv6hdr *)skb->data;
 431	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
 432				 tpi.key, tpi.proto);
 433	if (!t)
 434		return -ENOENT;
 435
 436	switch (type) {
 437	case ICMPV6_DEST_UNREACH:
 438		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
 439				    t->parms.name);
 440		if (code != ICMPV6_PORT_UNREACH)
 441			break;
 442		return 0;
 443	case ICMPV6_TIME_EXCEED:
 444		if (code == ICMPV6_EXC_HOPLIMIT) {
 445			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
 446					    t->parms.name);
 447			break;
 448		}
 449		return 0;
 450	case ICMPV6_PARAMPROB: {
 451		struct ipv6_tlv_tnl_enc_lim *tel;
 452		__u32 teli;
 453
 454		teli = 0;
 455		if (code == ICMPV6_HDR_FIELD)
 456			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 457
 458		if (teli && teli == be32_to_cpu(info) - 2) {
 459			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
 460			if (tel->encap_limit == 0) {
 461				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
 462						    t->parms.name);
 463			}
 464		} else {
 465			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
 466					    t->parms.name);
 467		}
 468		return 0;
 469	}
 470	case ICMPV6_PKT_TOOBIG:
 471		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
 472		return 0;
 473	case NDISC_REDIRECT:
 474		ip6_redirect(skb, net, skb->dev->ifindex, 0,
 475			     sock_net_uid(net, NULL));
 476		return 0;
 477	}
 478
 479	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
 480		t->err_count++;
 481	else
 482		t->err_count = 1;
 483	t->err_time = jiffies;
 484
 485	return 0;
 486}
 487
 488static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
 489{
 490	const struct ipv6hdr *ipv6h;
 491	struct ip6_tnl *tunnel;
 492
 493	ipv6h = ipv6_hdr(skb);
 494	tunnel = ip6gre_tunnel_lookup(skb->dev,
 495				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
 496				      tpi->proto);
 497	if (tunnel) {
 498		if (tunnel->parms.collect_md) {
 499			struct metadata_dst *tun_dst;
 500			__be64 tun_id;
 501			__be16 flags;
 502
 503			flags = tpi->flags;
 504			tun_id = key32_to_tunnel_id(tpi->key);
 505
 506			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
 507			if (!tun_dst)
 508				return PACKET_REJECT;
 509
 510			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 511		} else {
 512			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
 513		}
 514
 515		return PACKET_RCVD;
 516	}
 517
 518	return PACKET_REJECT;
 519}
 520
 521static int ip6erspan_rcv(struct sk_buff *skb,
 522			 struct tnl_ptk_info *tpi,
 523			 int gre_hdr_len)
 524{
 525	struct erspan_base_hdr *ershdr;
 526	const struct ipv6hdr *ipv6h;
 527	struct erspan_md2 *md2;
 528	struct ip6_tnl *tunnel;
 529	u8 ver;
 530
 531	ipv6h = ipv6_hdr(skb);
 532	ershdr = (struct erspan_base_hdr *)skb->data;
 533	ver = ershdr->ver;
 534
 535	tunnel = ip6gre_tunnel_lookup(skb->dev,
 536				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
 537				      tpi->proto);
 538	if (tunnel) {
 539		int len = erspan_hdr_len(ver);
 540
 541		if (unlikely(!pskb_may_pull(skb, len)))
 542			return PACKET_REJECT;
 543
 544		if (__iptunnel_pull_header(skb, len,
 545					   htons(ETH_P_TEB),
 546					   false, false) < 0)
 547			return PACKET_REJECT;
 548
 549		if (tunnel->parms.collect_md) {
 550			struct erspan_metadata *pkt_md, *md;
 551			struct metadata_dst *tun_dst;
 552			struct ip_tunnel_info *info;
 553			unsigned char *gh;
 554			__be64 tun_id;
 555			__be16 flags;
 556
 557			tpi->flags |= TUNNEL_KEY;
 558			flags = tpi->flags;
 559			tun_id = key32_to_tunnel_id(tpi->key);
 560
 561			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
 562						  sizeof(*md));
 563			if (!tun_dst)
 564				return PACKET_REJECT;
 565
 566			/* skb can be uncloned in __iptunnel_pull_header, so
 567			 * old pkt_md is no longer valid and we need to reset
 568			 * it
 569			 */
 570			gh = skb_network_header(skb) +
 571			     skb_network_header_len(skb);
 572			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
 573							    sizeof(*ershdr));
 574			info = &tun_dst->u.tun_info;
 575			md = ip_tunnel_info_opts(info);
 576			md->version = ver;
 577			md2 = &md->u.md2;
 578			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
 579						       ERSPAN_V2_MDSIZE);
 580			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
 581			info->options_len = sizeof(*md);
 582
 583			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 584
 585		} else {
 586			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
 587		}
 588
 589		return PACKET_RCVD;
 590	}
 591
 592	return PACKET_REJECT;
 593}
 594
 595static int gre_rcv(struct sk_buff *skb)
 596{
 597	struct tnl_ptk_info tpi;
 598	bool csum_err = false;
 599	int hdr_len;
 600
 601	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
 602	if (hdr_len < 0)
 603		goto drop;
 604
 605	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
 606		goto drop;
 607
 608	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
 609		     tpi.proto == htons(ETH_P_ERSPAN2))) {
 610		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
 611			return 0;
 612		goto out;
 613	}
 614
 615	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
 616		return 0;
 617
 618out:
 619	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 620drop:
 621	kfree_skb(skb);
 622	return 0;
 623}
 624
 625static int gre_handle_offloads(struct sk_buff *skb, bool csum)
 626{
 627	return iptunnel_handle_offloads(skb,
 628					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
 629}
 630
 631static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
 632				     struct net_device *dev,
 633				     struct flowi6 *fl6, __u8 *dsfield,
 634				     int *encap_limit)
 635{
 636	const struct iphdr *iph = ip_hdr(skb);
 637	struct ip6_tnl *t = netdev_priv(dev);
 638
 639	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 640		*encap_limit = t->parms.encap_limit;
 641
 642	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 643
 644	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 645		*dsfield = ipv4_get_dsfield(iph);
 646	else
 647		*dsfield = ip6_tclass(t->parms.flowinfo);
 648
 649	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 650		fl6->flowi6_mark = skb->mark;
 651	else
 652		fl6->flowi6_mark = t->parms.fwmark;
 653
 654	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 655}
 656
 657static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
 658				    struct net_device *dev,
 659				    struct flowi6 *fl6, __u8 *dsfield,
 660				    int *encap_limit)
 661{
 662	struct ipv6hdr *ipv6h;
 663	struct ip6_tnl *t = netdev_priv(dev);
 664	__u16 offset;
 665
 666	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
 667	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
 668	ipv6h = ipv6_hdr(skb);
 669
 670	if (offset > 0) {
 671		struct ipv6_tlv_tnl_enc_lim *tel;
 672
 673		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
 674		if (tel->encap_limit == 0) {
 675			icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
 676					ICMPV6_HDR_FIELD, offset + 2);
 677			return -1;
 678		}
 679		*encap_limit = tel->encap_limit - 1;
 680	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
 681		*encap_limit = t->parms.encap_limit;
 682	}
 683
 684	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 685
 686	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 687		*dsfield = ipv6_get_dsfield(ipv6h);
 688	else
 689		*dsfield = ip6_tclass(t->parms.flowinfo);
 690
 691	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 692		fl6->flowlabel |= ip6_flowlabel(ipv6h);
 693
 694	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 695		fl6->flowi6_mark = skb->mark;
 696	else
 697		fl6->flowi6_mark = t->parms.fwmark;
 698
 699	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 700
 701	return 0;
 702}
 703
 704static int prepare_ip6gre_xmit_other(struct sk_buff *skb,
 705				     struct net_device *dev,
 706				     struct flowi6 *fl6, __u8 *dsfield,
 707				     int *encap_limit)
 708{
 709	struct ip6_tnl *t = netdev_priv(dev);
 710
 711	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
 712		*encap_limit = t->parms.encap_limit;
 713
 714	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
 715
 716	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
 717		*dsfield = 0;
 718	else
 719		*dsfield = ip6_tclass(t->parms.flowinfo);
 720
 721	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 722		fl6->flowi6_mark = skb->mark;
 723	else
 724		fl6->flowi6_mark = t->parms.fwmark;
 725
 726	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 727
 728	return 0;
 729}
 730
 731static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
 732{
 733	struct ip_tunnel_info *tun_info;
 734
 735	tun_info = skb_tunnel_info(skb);
 736	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
 737		return ERR_PTR(-EINVAL);
 738
 739	return tun_info;
 740}
 741
 742static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
 743			       struct net_device *dev, __u8 dsfield,
 744			       struct flowi6 *fl6, int encap_limit,
 745			       __u32 *pmtu, __be16 proto)
 746{
 747	struct ip6_tnl *tunnel = netdev_priv(dev);
 748	__be16 protocol;
 749	__be16 flags;
 750
 751	if (dev->type == ARPHRD_ETHER)
 752		IPCB(skb)->flags = 0;
 753
 754	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
 755		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
 756	else
 757		fl6->daddr = tunnel->parms.raddr;
 758
 759	/* Push GRE header. */
 760	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
 761
 762	if (tunnel->parms.collect_md) {
 763		struct ip_tunnel_info *tun_info;
 764		const struct ip_tunnel_key *key;
 765		int tun_hlen;
 766
 767		tun_info = skb_tunnel_info_txcheck(skb);
 768		if (IS_ERR(tun_info) ||
 769		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 770			return -EINVAL;
 771
 772		key = &tun_info->key;
 773		memset(fl6, 0, sizeof(*fl6));
 774		fl6->flowi6_proto = IPPROTO_GRE;
 775		fl6->daddr = key->u.ipv6.dst;
 776		fl6->flowlabel = key->label;
 777		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
 778		fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
 779
 780		dsfield = key->tos;
 781		flags = key->tun_flags &
 782			(TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
 783		tun_hlen = gre_calc_hlen(flags);
 784
 785		if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
 786			return -ENOMEM;
 787
 788		gre_build_header(skb, tun_hlen,
 789				 flags, protocol,
 790				 tunnel_id_to_key32(tun_info->key.tun_id),
 791				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
 792						      : 0);
 793
 794	} else {
 795		if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
 796			return -ENOMEM;
 797
 798		flags = tunnel->parms.o_flags;
 799
 800		gre_build_header(skb, tunnel->tun_hlen, flags,
 801				 protocol, tunnel->parms.o_key,
 802				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
 803						      : 0);
 804	}
 805
 806	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
 807			    NEXTHDR_GRE);
 808}
 809
 810static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
 811{
 812	struct ip6_tnl *t = netdev_priv(dev);
 813	int encap_limit = -1;
 814	struct flowi6 fl6;
 815	__u8 dsfield = 0;
 816	__u32 mtu;
 817	int err;
 818
 819	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 820
 821	if (!t->parms.collect_md)
 822		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
 823					 &dsfield, &encap_limit);
 824
 825	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 826	if (err)
 827		return -1;
 828
 829	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
 830			  skb->protocol);
 831	if (err != 0) {
 832		/* XXX: send ICMP error even if DF is not set. */
 833		if (err == -EMSGSIZE)
 834			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
 835				      htonl(mtu));
 836		return -1;
 837	}
 838
 839	return 0;
 840}
 841
 842static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
 843{
 844	struct ip6_tnl *t = netdev_priv(dev);
 845	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 846	int encap_limit = -1;
 847	struct flowi6 fl6;
 848	__u8 dsfield = 0;
 849	__u32 mtu;
 850	int err;
 851
 852	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
 853		return -1;
 854
 855	if (!t->parms.collect_md &&
 856	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
 857		return -1;
 858
 859	if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
 860		return -1;
 861
 862	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
 863			  &mtu, skb->protocol);
 864	if (err != 0) {
 865		if (err == -EMSGSIZE)
 866			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 867		return -1;
 868	}
 869
 870	return 0;
 871}
 872
 873static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
 874{
 875	struct ip6_tnl *t = netdev_priv(dev);
 876	int encap_limit = -1;
 877	struct flowi6 fl6;
 878	__u8 dsfield = 0;
 879	__u32 mtu;
 880	int err;
 881
 882	if (!t->parms.collect_md &&
 883	    prepare_ip6gre_xmit_other(skb, dev, &fl6, &dsfield, &encap_limit))
 884		return -1;
 885
 886	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
 887	if (err)
 888		return err;
 889	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, skb->protocol);
 890
 891	return err;
 892}
 893
 894static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
 895	struct net_device *dev)
 896{
 897	struct ip6_tnl *t = netdev_priv(dev);
 898	__be16 payload_protocol;
 899	int ret;
 900
 901	if (!pskb_inet_may_pull(skb))
 902		goto tx_err;
 903
 904	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 905		goto tx_err;
 906
 907	payload_protocol = skb_protocol(skb, true);
 908	switch (payload_protocol) {
 909	case htons(ETH_P_IP):
 910		ret = ip6gre_xmit_ipv4(skb, dev);
 911		break;
 912	case htons(ETH_P_IPV6):
 913		ret = ip6gre_xmit_ipv6(skb, dev);
 914		break;
 915	default:
 916		ret = ip6gre_xmit_other(skb, dev);
 917		break;
 918	}
 919
 920	if (ret < 0)
 921		goto tx_err;
 922
 923	return NETDEV_TX_OK;
 924
 925tx_err:
 926	if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
 927		DEV_STATS_INC(dev, tx_errors);
 928	DEV_STATS_INC(dev, tx_dropped);
 929	kfree_skb(skb);
 930	return NETDEV_TX_OK;
 931}
 932
 933static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
 934					 struct net_device *dev)
 935{
 936	struct ip_tunnel_info *tun_info = NULL;
 937	struct ip6_tnl *t = netdev_priv(dev);
 938	struct dst_entry *dst = skb_dst(skb);
 939	bool truncate = false;
 940	int encap_limit = -1;
 941	__u8 dsfield = false;
 942	struct flowi6 fl6;
 943	int err = -EINVAL;
 944	__be16 proto;
 945	__u32 mtu;
 946	int nhoff;
 947
 948	if (!pskb_inet_may_pull(skb))
 949		goto tx_err;
 950
 951	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
 952		goto tx_err;
 953
 954	if (gre_handle_offloads(skb, false))
 955		goto tx_err;
 956
 957	if (skb->len > dev->mtu + dev->hard_header_len) {
 958		pskb_trim(skb, dev->mtu + dev->hard_header_len);
 959		truncate = true;
 960	}
 961
 962	nhoff = skb_network_header(skb) - skb_mac_header(skb);
 963	if (skb->protocol == htons(ETH_P_IP) &&
 964	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
 965		truncate = true;
 966
 967	if (skb->protocol == htons(ETH_P_IPV6)) {
 968		int thoff;
 969
 970		if (skb_transport_header_was_set(skb))
 971			thoff = skb_transport_header(skb) - skb_mac_header(skb);
 972		else
 973			thoff = nhoff + sizeof(struct ipv6hdr);
 974		if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
 975			truncate = true;
 976	}
 977
 978	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
 979		goto tx_err;
 980
 981	t->parms.o_flags &= ~TUNNEL_KEY;
 982	IPCB(skb)->flags = 0;
 983
 984	/* For collect_md mode, derive fl6 from the tunnel key,
 985	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
 986	 */
 987	if (t->parms.collect_md) {
 988		const struct ip_tunnel_key *key;
 989		struct erspan_metadata *md;
 990		__be32 tun_id;
 991
 992		tun_info = skb_tunnel_info_txcheck(skb);
 993		if (IS_ERR(tun_info) ||
 994		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
 995			goto tx_err;
 996
 997		key = &tun_info->key;
 998		memset(&fl6, 0, sizeof(fl6));
 999		fl6.flowi6_proto = IPPROTO_GRE;
1000		fl6.daddr = key->u.ipv6.dst;
1001		fl6.flowlabel = key->label;
1002		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1003		fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
1004
1005		dsfield = key->tos;
1006		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
1007			goto tx_err;
1008		if (tun_info->options_len < sizeof(*md))
1009			goto tx_err;
1010		md = ip_tunnel_info_opts(tun_info);
1011
1012		tun_id = tunnel_id_to_key32(key->tun_id);
1013		if (md->version == 1) {
1014			erspan_build_header(skb,
1015					    ntohl(tun_id),
1016					    ntohl(md->u.index), truncate,
1017					    false);
1018		} else if (md->version == 2) {
1019			erspan_build_header_v2(skb,
1020					       ntohl(tun_id),
1021					       md->u.md2.dir,
1022					       get_hwid(&md->u.md2),
1023					       truncate, false);
1024		} else {
1025			goto tx_err;
1026		}
1027	} else {
1028		switch (skb->protocol) {
1029		case htons(ETH_P_IP):
1030			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1031			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1032						 &dsfield, &encap_limit);
1033			break;
1034		case htons(ETH_P_IPV6):
1035			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1036				goto tx_err;
1037			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1038						     &dsfield, &encap_limit))
1039				goto tx_err;
1040			break;
1041		default:
1042			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1043			break;
1044		}
1045
1046		if (t->parms.erspan_ver == 1)
1047			erspan_build_header(skb, ntohl(t->parms.o_key),
1048					    t->parms.index,
1049					    truncate, false);
1050		else if (t->parms.erspan_ver == 2)
1051			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1052					       t->parms.dir,
1053					       t->parms.hwid,
1054					       truncate, false);
1055		else
1056			goto tx_err;
1057
1058		fl6.daddr = t->parms.raddr;
1059	}
1060
1061	/* Push GRE header. */
1062	proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1063					   : htons(ETH_P_ERSPAN2);
1064	gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(atomic_fetch_inc(&t->o_seqno)));
1065
1066	/* TooBig packet may have updated dst->dev's mtu */
1067	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1068		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1069
1070	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1071			   NEXTHDR_GRE);
1072	if (err != 0) {
1073		/* XXX: send ICMP error even if DF is not set. */
1074		if (err == -EMSGSIZE) {
1075			if (skb->protocol == htons(ETH_P_IP))
1076				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1077					      ICMP_FRAG_NEEDED, htonl(mtu));
1078			else
1079				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1080		}
1081
1082		goto tx_err;
1083	}
1084	return NETDEV_TX_OK;
1085
1086tx_err:
1087	if (!IS_ERR(tun_info))
1088		DEV_STATS_INC(dev, tx_errors);
1089	DEV_STATS_INC(dev, tx_dropped);
1090	kfree_skb(skb);
1091	return NETDEV_TX_OK;
1092}
1093
1094static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1095{
1096	struct net_device *dev = t->dev;
1097	struct __ip6_tnl_parm *p = &t->parms;
1098	struct flowi6 *fl6 = &t->fl.u.ip6;
1099
1100	if (dev->type != ARPHRD_ETHER) {
1101		__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1102		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1103	}
1104
1105	/* Set up flowi template */
1106	fl6->saddr = p->laddr;
1107	fl6->daddr = p->raddr;
1108	fl6->flowi6_oif = p->link;
1109	fl6->flowlabel = 0;
1110	fl6->flowi6_proto = IPPROTO_GRE;
1111	fl6->fl6_gre_key = t->parms.o_key;
1112
1113	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1114		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1115	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1116		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1117
1118	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1119	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1120
1121	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1122			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1123		dev->flags |= IFF_POINTOPOINT;
1124	else
1125		dev->flags &= ~IFF_POINTOPOINT;
1126}
1127
1128static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1129					 int t_hlen)
1130{
1131	const struct __ip6_tnl_parm *p = &t->parms;
1132	struct net_device *dev = t->dev;
1133
1134	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1135		int strict = (ipv6_addr_type(&p->raddr) &
1136			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1137
1138		struct rt6_info *rt = rt6_lookup(t->net,
1139						 &p->raddr, &p->laddr,
1140						 p->link, NULL, strict);
1141
1142		if (!rt)
1143			return;
1144
1145		if (rt->dst.dev) {
1146			unsigned short dst_len = rt->dst.dev->hard_header_len +
1147						 t_hlen;
1148
1149			if (t->dev->header_ops)
1150				dev->hard_header_len = dst_len;
1151			else
1152				dev->needed_headroom = dst_len;
1153
1154			if (set_mtu) {
1155				int mtu = rt->dst.dev->mtu - t_hlen;
1156
1157				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1158					mtu -= 8;
1159				if (dev->type == ARPHRD_ETHER)
1160					mtu -= ETH_HLEN;
1161
1162				if (mtu < IPV6_MIN_MTU)
1163					mtu = IPV6_MIN_MTU;
1164				WRITE_ONCE(dev->mtu, mtu);
1165			}
1166		}
1167		ip6_rt_put(rt);
1168	}
1169}
1170
1171static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1172{
1173	int t_hlen;
1174
1175	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1176	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1177
1178	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1179
1180	if (tunnel->dev->header_ops)
1181		tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1182	else
1183		tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1184
1185	return t_hlen;
1186}
1187
1188static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1189{
1190	ip6gre_tnl_link_config_common(t);
1191	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1192}
1193
1194static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1195				     const struct __ip6_tnl_parm *p)
1196{
1197	t->parms.laddr = p->laddr;
1198	t->parms.raddr = p->raddr;
1199	t->parms.flags = p->flags;
1200	t->parms.hop_limit = p->hop_limit;
1201	t->parms.encap_limit = p->encap_limit;
1202	t->parms.flowinfo = p->flowinfo;
1203	t->parms.link = p->link;
1204	t->parms.proto = p->proto;
1205	t->parms.i_key = p->i_key;
1206	t->parms.o_key = p->o_key;
1207	t->parms.i_flags = p->i_flags;
1208	t->parms.o_flags = p->o_flags;
1209	t->parms.fwmark = p->fwmark;
1210	t->parms.erspan_ver = p->erspan_ver;
1211	t->parms.index = p->index;
1212	t->parms.dir = p->dir;
1213	t->parms.hwid = p->hwid;
1214	dst_cache_reset(&t->dst_cache);
1215}
1216
1217static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1218			     int set_mtu)
1219{
1220	ip6gre_tnl_copy_tnl_parm(t, p);
1221	ip6gre_tnl_link_config(t, set_mtu);
1222	return 0;
1223}
1224
1225static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1226	const struct ip6_tnl_parm2 *u)
1227{
1228	p->laddr = u->laddr;
1229	p->raddr = u->raddr;
1230	p->flags = u->flags;
1231	p->hop_limit = u->hop_limit;
1232	p->encap_limit = u->encap_limit;
1233	p->flowinfo = u->flowinfo;
1234	p->link = u->link;
1235	p->i_key = u->i_key;
1236	p->o_key = u->o_key;
1237	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1238	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1239	memcpy(p->name, u->name, sizeof(u->name));
1240}
1241
1242static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1243	const struct __ip6_tnl_parm *p)
1244{
1245	u->proto = IPPROTO_GRE;
1246	u->laddr = p->laddr;
1247	u->raddr = p->raddr;
1248	u->flags = p->flags;
1249	u->hop_limit = p->hop_limit;
1250	u->encap_limit = p->encap_limit;
1251	u->flowinfo = p->flowinfo;
1252	u->link = p->link;
1253	u->i_key = p->i_key;
1254	u->o_key = p->o_key;
1255	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1256	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1257	memcpy(u->name, p->name, sizeof(u->name));
1258}
1259
1260static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1261					struct ifreq *ifr, void __user *data,
1262					int cmd)
1263{
1264	int err = 0;
1265	struct ip6_tnl_parm2 p;
1266	struct __ip6_tnl_parm p1;
1267	struct ip6_tnl *t = netdev_priv(dev);
1268	struct net *net = t->net;
1269	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1270
1271	memset(&p1, 0, sizeof(p1));
1272
1273	switch (cmd) {
1274	case SIOCGETTUNNEL:
1275		if (dev == ign->fb_tunnel_dev) {
1276			if (copy_from_user(&p, data, sizeof(p))) {
1277				err = -EFAULT;
1278				break;
1279			}
1280			ip6gre_tnl_parm_from_user(&p1, &p);
1281			t = ip6gre_tunnel_locate(net, &p1, 0);
1282			if (!t)
1283				t = netdev_priv(dev);
1284		}
1285		memset(&p, 0, sizeof(p));
1286		ip6gre_tnl_parm_to_user(&p, &t->parms);
1287		if (copy_to_user(data, &p, sizeof(p)))
1288			err = -EFAULT;
1289		break;
1290
1291	case SIOCADDTUNNEL:
1292	case SIOCCHGTUNNEL:
1293		err = -EPERM;
1294		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1295			goto done;
1296
1297		err = -EFAULT;
1298		if (copy_from_user(&p, data, sizeof(p)))
1299			goto done;
1300
1301		err = -EINVAL;
1302		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1303			goto done;
1304
1305		if (!(p.i_flags&GRE_KEY))
1306			p.i_key = 0;
1307		if (!(p.o_flags&GRE_KEY))
1308			p.o_key = 0;
1309
1310		ip6gre_tnl_parm_from_user(&p1, &p);
1311		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1312
1313		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1314			if (t) {
1315				if (t->dev != dev) {
1316					err = -EEXIST;
1317					break;
1318				}
1319			} else {
1320				t = netdev_priv(dev);
1321
1322				ip6gre_tunnel_unlink(ign, t);
1323				synchronize_net();
1324				ip6gre_tnl_change(t, &p1, 1);
1325				ip6gre_tunnel_link(ign, t);
1326				netdev_state_change(dev);
1327			}
1328		}
1329
1330		if (t) {
1331			err = 0;
1332
1333			memset(&p, 0, sizeof(p));
1334			ip6gre_tnl_parm_to_user(&p, &t->parms);
1335			if (copy_to_user(data, &p, sizeof(p)))
1336				err = -EFAULT;
1337		} else
1338			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1339		break;
1340
1341	case SIOCDELTUNNEL:
1342		err = -EPERM;
1343		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1344			goto done;
1345
1346		if (dev == ign->fb_tunnel_dev) {
1347			err = -EFAULT;
1348			if (copy_from_user(&p, data, sizeof(p)))
1349				goto done;
1350			err = -ENOENT;
1351			ip6gre_tnl_parm_from_user(&p1, &p);
1352			t = ip6gre_tunnel_locate(net, &p1, 0);
1353			if (!t)
1354				goto done;
1355			err = -EPERM;
1356			if (t == netdev_priv(ign->fb_tunnel_dev))
1357				goto done;
1358			dev = t->dev;
1359		}
1360		unregister_netdevice(dev);
1361		err = 0;
1362		break;
1363
1364	default:
1365		err = -EINVAL;
1366	}
1367
1368done:
1369	return err;
1370}
1371
1372static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1373			 unsigned short type, const void *daddr,
1374			 const void *saddr, unsigned int len)
1375{
1376	struct ip6_tnl *t = netdev_priv(dev);
1377	struct ipv6hdr *ipv6h;
1378	__be16 *p;
1379
1380	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1381	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1382						  t->fl.u.ip6.flowlabel,
1383						  true, &t->fl.u.ip6));
1384	ipv6h->hop_limit = t->parms.hop_limit;
1385	ipv6h->nexthdr = NEXTHDR_GRE;
1386	ipv6h->saddr = t->parms.laddr;
1387	ipv6h->daddr = t->parms.raddr;
1388
1389	p = (__be16 *)(ipv6h + 1);
1390	p[0] = t->parms.o_flags;
1391	p[1] = htons(type);
1392
1393	/*
1394	 *	Set the source hardware address.
1395	 */
1396
1397	if (saddr)
1398		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1399	if (daddr)
1400		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1401	if (!ipv6_addr_any(&ipv6h->daddr))
1402		return t->hlen;
1403
1404	return -t->hlen;
1405}
1406
1407static const struct header_ops ip6gre_header_ops = {
1408	.create	= ip6gre_header,
1409};
1410
1411static const struct net_device_ops ip6gre_netdev_ops = {
1412	.ndo_init		= ip6gre_tunnel_init,
1413	.ndo_uninit		= ip6gre_tunnel_uninit,
1414	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1415	.ndo_siocdevprivate	= ip6gre_tunnel_siocdevprivate,
1416	.ndo_change_mtu		= ip6_tnl_change_mtu,
1417	.ndo_get_stats64	= dev_get_tstats64,
1418	.ndo_get_iflink		= ip6_tnl_get_iflink,
1419};
1420
1421static void ip6gre_dev_free(struct net_device *dev)
1422{
1423	struct ip6_tnl *t = netdev_priv(dev);
1424
1425	gro_cells_destroy(&t->gro_cells);
1426	dst_cache_destroy(&t->dst_cache);
1427	free_percpu(dev->tstats);
1428}
1429
1430static void ip6gre_tunnel_setup(struct net_device *dev)
1431{
1432	dev->netdev_ops = &ip6gre_netdev_ops;
1433	dev->needs_free_netdev = true;
1434	dev->priv_destructor = ip6gre_dev_free;
1435
1436	dev->type = ARPHRD_IP6GRE;
1437
1438	dev->flags |= IFF_NOARP;
1439	dev->addr_len = sizeof(struct in6_addr);
1440	netif_keep_dst(dev);
1441	/* This perm addr will be used as interface identifier by IPv6 */
1442	dev->addr_assign_type = NET_ADDR_RANDOM;
1443	eth_random_addr(dev->perm_addr);
1444}
1445
1446#define GRE6_FEATURES (NETIF_F_SG |		\
1447		       NETIF_F_FRAGLIST |	\
1448		       NETIF_F_HIGHDMA |	\
1449		       NETIF_F_HW_CSUM)
1450
1451static void ip6gre_tnl_init_features(struct net_device *dev)
1452{
1453	struct ip6_tnl *nt = netdev_priv(dev);
1454	__be16 flags;
1455
1456	dev->features		|= GRE6_FEATURES | NETIF_F_LLTX;
1457	dev->hw_features	|= GRE6_FEATURES;
1458
1459	flags = nt->parms.o_flags;
1460
1461	/* TCP offload with GRE SEQ is not supported, nor can we support 2
1462	 * levels of outer headers requiring an update.
1463	 */
1464	if (flags & TUNNEL_SEQ)
1465		return;
1466	if (flags & TUNNEL_CSUM && nt->encap.type != TUNNEL_ENCAP_NONE)
1467		return;
1468
1469	dev->features |= NETIF_F_GSO_SOFTWARE;
1470	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1471}
1472
1473static int ip6gre_tunnel_init_common(struct net_device *dev)
1474{
1475	struct ip6_tnl *tunnel;
1476	int ret;
1477	int t_hlen;
1478
1479	tunnel = netdev_priv(dev);
1480
1481	tunnel->dev = dev;
1482	tunnel->net = dev_net(dev);
1483	strcpy(tunnel->parms.name, dev->name);
1484
1485	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1486	if (!dev->tstats)
1487		return -ENOMEM;
1488
1489	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1490	if (ret)
1491		goto cleanup_alloc_pcpu_stats;
1492
1493	ret = gro_cells_init(&tunnel->gro_cells, dev);
1494	if (ret)
1495		goto cleanup_dst_cache_init;
1496
1497	t_hlen = ip6gre_calc_hlen(tunnel);
1498	dev->mtu = ETH_DATA_LEN - t_hlen;
1499	if (dev->type == ARPHRD_ETHER)
1500		dev->mtu -= ETH_HLEN;
1501	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1502		dev->mtu -= 8;
1503
1504	if (tunnel->parms.collect_md) {
1505		netif_keep_dst(dev);
1506	}
1507	ip6gre_tnl_init_features(dev);
1508
1509	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1510	return 0;
1511
1512cleanup_dst_cache_init:
1513	dst_cache_destroy(&tunnel->dst_cache);
1514cleanup_alloc_pcpu_stats:
1515	free_percpu(dev->tstats);
1516	dev->tstats = NULL;
1517	return ret;
1518}
1519
1520static int ip6gre_tunnel_init(struct net_device *dev)
1521{
1522	struct ip6_tnl *tunnel;
1523	int ret;
1524
1525	ret = ip6gre_tunnel_init_common(dev);
1526	if (ret)
1527		return ret;
1528
1529	tunnel = netdev_priv(dev);
1530
1531	if (tunnel->parms.collect_md)
1532		return 0;
1533
1534	__dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1535	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1536
1537	if (ipv6_addr_any(&tunnel->parms.raddr))
1538		dev->header_ops = &ip6gre_header_ops;
1539
1540	return 0;
1541}
1542
1543static void ip6gre_fb_tunnel_init(struct net_device *dev)
1544{
1545	struct ip6_tnl *tunnel = netdev_priv(dev);
1546
1547	tunnel->dev = dev;
1548	tunnel->net = dev_net(dev);
1549	strcpy(tunnel->parms.name, dev->name);
1550
1551	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1552}
1553
1554static struct inet6_protocol ip6gre_protocol __read_mostly = {
1555	.handler     = gre_rcv,
1556	.err_handler = ip6gre_err,
1557	.flags       = INET6_PROTO_FINAL,
1558};
1559
1560static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1561{
1562	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1563	struct net_device *dev, *aux;
1564	int prio;
1565
1566	for_each_netdev_safe(net, dev, aux)
1567		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1568		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1569		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1570			unregister_netdevice_queue(dev, head);
1571
1572	for (prio = 0; prio < 4; prio++) {
1573		int h;
1574		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1575			struct ip6_tnl *t;
1576
1577			t = rtnl_dereference(ign->tunnels[prio][h]);
1578
1579			while (t) {
1580				/* If dev is in the same netns, it has already
1581				 * been added to the list by the previous loop.
1582				 */
1583				if (!net_eq(dev_net(t->dev), net))
1584					unregister_netdevice_queue(t->dev,
1585								   head);
1586				t = rtnl_dereference(t->next);
1587			}
1588		}
1589	}
1590}
1591
1592static int __net_init ip6gre_init_net(struct net *net)
1593{
1594	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1595	struct net_device *ndev;
1596	int err;
1597
1598	if (!net_has_fallback_tunnels(net))
1599		return 0;
1600	ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1601			    NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1602	if (!ndev) {
1603		err = -ENOMEM;
1604		goto err_alloc_dev;
1605	}
1606	ign->fb_tunnel_dev = ndev;
1607	dev_net_set(ign->fb_tunnel_dev, net);
1608	/* FB netdevice is special: we have one, and only one per netns.
1609	 * Allowing to move it to another netns is clearly unsafe.
1610	 */
1611	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1612
1613
1614	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1615	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1616
1617	err = register_netdev(ign->fb_tunnel_dev);
1618	if (err)
1619		goto err_reg_dev;
1620
1621	rcu_assign_pointer(ign->tunnels_wc[0],
1622			   netdev_priv(ign->fb_tunnel_dev));
1623	return 0;
1624
1625err_reg_dev:
1626	free_netdev(ndev);
1627err_alloc_dev:
1628	return err;
1629}
1630
1631static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1632{
1633	struct net *net;
1634	LIST_HEAD(list);
1635
1636	rtnl_lock();
1637	list_for_each_entry(net, net_list, exit_list)
1638		ip6gre_destroy_tunnels(net, &list);
1639	unregister_netdevice_many(&list);
1640	rtnl_unlock();
1641}
1642
1643static struct pernet_operations ip6gre_net_ops = {
1644	.init = ip6gre_init_net,
1645	.exit_batch = ip6gre_exit_batch_net,
1646	.id   = &ip6gre_net_id,
1647	.size = sizeof(struct ip6gre_net),
1648};
1649
1650static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1651				  struct netlink_ext_ack *extack)
1652{
1653	__be16 flags;
1654
1655	if (!data)
1656		return 0;
1657
1658	flags = 0;
1659	if (data[IFLA_GRE_IFLAGS])
1660		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1661	if (data[IFLA_GRE_OFLAGS])
1662		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1663	if (flags & (GRE_VERSION|GRE_ROUTING))
1664		return -EINVAL;
1665
1666	return 0;
1667}
1668
1669static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1670			       struct netlink_ext_ack *extack)
1671{
1672	struct in6_addr daddr;
1673
1674	if (tb[IFLA_ADDRESS]) {
1675		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1676			return -EINVAL;
1677		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1678			return -EADDRNOTAVAIL;
1679	}
1680
1681	if (!data)
1682		goto out;
1683
1684	if (data[IFLA_GRE_REMOTE]) {
1685		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1686		if (ipv6_addr_any(&daddr))
1687			return -EINVAL;
1688	}
1689
1690out:
1691	return ip6gre_tunnel_validate(tb, data, extack);
1692}
1693
1694static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1695				  struct netlink_ext_ack *extack)
1696{
1697	__be16 flags = 0;
1698	int ret, ver = 0;
1699
1700	if (!data)
1701		return 0;
1702
1703	ret = ip6gre_tap_validate(tb, data, extack);
1704	if (ret)
1705		return ret;
1706
1707	/* ERSPAN should only have GRE sequence and key flag */
1708	if (data[IFLA_GRE_OFLAGS])
1709		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1710	if (data[IFLA_GRE_IFLAGS])
1711		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1712	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1713	    flags != (GRE_SEQ | GRE_KEY))
1714		return -EINVAL;
1715
1716	/* ERSPAN Session ID only has 10-bit. Since we reuse
1717	 * 32-bit key field as ID, check it's range.
1718	 */
1719	if (data[IFLA_GRE_IKEY] &&
1720	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1721		return -EINVAL;
1722
1723	if (data[IFLA_GRE_OKEY] &&
1724	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1725		return -EINVAL;
1726
1727	if (data[IFLA_GRE_ERSPAN_VER]) {
1728		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1729		if (ver != 1 && ver != 2)
1730			return -EINVAL;
1731	}
1732
1733	if (ver == 1) {
1734		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1735			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1736
1737			if (index & ~INDEX_MASK)
1738				return -EINVAL;
1739		}
1740	} else if (ver == 2) {
1741		if (data[IFLA_GRE_ERSPAN_DIR]) {
1742			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1743
1744			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1745				return -EINVAL;
1746		}
1747
1748		if (data[IFLA_GRE_ERSPAN_HWID]) {
1749			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1750
1751			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1752				return -EINVAL;
1753		}
1754	}
1755
1756	return 0;
1757}
1758
1759static void ip6erspan_set_version(struct nlattr *data[],
1760				  struct __ip6_tnl_parm *parms)
1761{
1762	if (!data)
1763		return;
1764
1765	parms->erspan_ver = 1;
1766	if (data[IFLA_GRE_ERSPAN_VER])
1767		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1768
1769	if (parms->erspan_ver == 1) {
1770		if (data[IFLA_GRE_ERSPAN_INDEX])
1771			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1772	} else if (parms->erspan_ver == 2) {
1773		if (data[IFLA_GRE_ERSPAN_DIR])
1774			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1775		if (data[IFLA_GRE_ERSPAN_HWID])
1776			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1777	}
1778}
1779
1780static void ip6gre_netlink_parms(struct nlattr *data[],
1781				struct __ip6_tnl_parm *parms)
1782{
1783	memset(parms, 0, sizeof(*parms));
1784
1785	if (!data)
1786		return;
1787
1788	if (data[IFLA_GRE_LINK])
1789		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1790
1791	if (data[IFLA_GRE_IFLAGS])
1792		parms->i_flags = gre_flags_to_tnl_flags(
1793				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1794
1795	if (data[IFLA_GRE_OFLAGS])
1796		parms->o_flags = gre_flags_to_tnl_flags(
1797				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1798
1799	if (data[IFLA_GRE_IKEY])
1800		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1801
1802	if (data[IFLA_GRE_OKEY])
1803		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1804
1805	if (data[IFLA_GRE_LOCAL])
1806		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1807
1808	if (data[IFLA_GRE_REMOTE])
1809		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1810
1811	if (data[IFLA_GRE_TTL])
1812		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1813
1814	if (data[IFLA_GRE_ENCAP_LIMIT])
1815		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1816
1817	if (data[IFLA_GRE_FLOWINFO])
1818		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1819
1820	if (data[IFLA_GRE_FLAGS])
1821		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1822
1823	if (data[IFLA_GRE_FWMARK])
1824		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1825
1826	if (data[IFLA_GRE_COLLECT_METADATA])
1827		parms->collect_md = true;
1828}
1829
1830static int ip6gre_tap_init(struct net_device *dev)
1831{
1832	int ret;
1833
1834	ret = ip6gre_tunnel_init_common(dev);
1835	if (ret)
1836		return ret;
1837
1838	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1839
1840	return 0;
1841}
1842
1843static const struct net_device_ops ip6gre_tap_netdev_ops = {
1844	.ndo_init = ip6gre_tap_init,
1845	.ndo_uninit = ip6gre_tunnel_uninit,
1846	.ndo_start_xmit = ip6gre_tunnel_xmit,
1847	.ndo_set_mac_address = eth_mac_addr,
1848	.ndo_validate_addr = eth_validate_addr,
1849	.ndo_change_mtu = ip6_tnl_change_mtu,
1850	.ndo_get_stats64 = dev_get_tstats64,
1851	.ndo_get_iflink = ip6_tnl_get_iflink,
1852};
1853
1854static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1855{
1856	int t_hlen;
1857
1858	tunnel->tun_hlen = 8;
1859	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1860		       erspan_hdr_len(tunnel->parms.erspan_ver);
1861
1862	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1863	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1864	return t_hlen;
1865}
1866
1867static int ip6erspan_tap_init(struct net_device *dev)
1868{
1869	struct ip6_tnl *tunnel;
1870	int t_hlen;
1871	int ret;
1872
1873	tunnel = netdev_priv(dev);
1874
1875	tunnel->dev = dev;
1876	tunnel->net = dev_net(dev);
1877	strcpy(tunnel->parms.name, dev->name);
1878
1879	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1880	if (!dev->tstats)
1881		return -ENOMEM;
1882
1883	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1884	if (ret)
1885		goto cleanup_alloc_pcpu_stats;
1886
1887	ret = gro_cells_init(&tunnel->gro_cells, dev);
1888	if (ret)
1889		goto cleanup_dst_cache_init;
1890
1891	t_hlen = ip6erspan_calc_hlen(tunnel);
1892	dev->mtu = ETH_DATA_LEN - t_hlen;
1893	if (dev->type == ARPHRD_ETHER)
1894		dev->mtu -= ETH_HLEN;
1895	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1896		dev->mtu -= 8;
1897
1898	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1899	ip6erspan_tnl_link_config(tunnel, 1);
1900
1901	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1902	return 0;
1903
1904cleanup_dst_cache_init:
1905	dst_cache_destroy(&tunnel->dst_cache);
1906cleanup_alloc_pcpu_stats:
1907	free_percpu(dev->tstats);
1908	dev->tstats = NULL;
1909	return ret;
1910}
1911
1912static const struct net_device_ops ip6erspan_netdev_ops = {
1913	.ndo_init =		ip6erspan_tap_init,
1914	.ndo_uninit =		ip6erspan_tunnel_uninit,
1915	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1916	.ndo_set_mac_address =	eth_mac_addr,
1917	.ndo_validate_addr =	eth_validate_addr,
1918	.ndo_change_mtu =	ip6_tnl_change_mtu,
1919	.ndo_get_stats64 =	dev_get_tstats64,
1920	.ndo_get_iflink =	ip6_tnl_get_iflink,
1921};
1922
1923static void ip6gre_tap_setup(struct net_device *dev)
1924{
1925
1926	ether_setup(dev);
1927
1928	dev->max_mtu = 0;
1929	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1930	dev->needs_free_netdev = true;
1931	dev->priv_destructor = ip6gre_dev_free;
1932
1933	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1934	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1935	netif_keep_dst(dev);
1936}
1937
1938static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1939				       struct ip_tunnel_encap *ipencap)
1940{
1941	bool ret = false;
1942
1943	memset(ipencap, 0, sizeof(*ipencap));
1944
1945	if (!data)
1946		return ret;
1947
1948	if (data[IFLA_GRE_ENCAP_TYPE]) {
1949		ret = true;
1950		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1951	}
1952
1953	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1954		ret = true;
1955		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1956	}
1957
1958	if (data[IFLA_GRE_ENCAP_SPORT]) {
1959		ret = true;
1960		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1961	}
1962
1963	if (data[IFLA_GRE_ENCAP_DPORT]) {
1964		ret = true;
1965		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1966	}
1967
1968	return ret;
1969}
1970
1971static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1972				 struct nlattr *tb[], struct nlattr *data[],
1973				 struct netlink_ext_ack *extack)
1974{
1975	struct ip6_tnl *nt;
1976	struct ip_tunnel_encap ipencap;
1977	int err;
1978
1979	nt = netdev_priv(dev);
1980
1981	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1982		int err = ip6_tnl_encap_setup(nt, &ipencap);
1983
1984		if (err < 0)
1985			return err;
1986	}
1987
1988	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1989		eth_hw_addr_random(dev);
1990
1991	nt->dev = dev;
1992	nt->net = dev_net(dev);
1993
1994	err = register_netdevice(dev);
1995	if (err)
1996		goto out;
1997
1998	if (tb[IFLA_MTU])
1999		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2000
2001out:
2002	return err;
2003}
2004
2005static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2006			  struct nlattr *tb[], struct nlattr *data[],
2007			  struct netlink_ext_ack *extack)
2008{
2009	struct ip6_tnl *nt = netdev_priv(dev);
2010	struct net *net = dev_net(dev);
2011	struct ip6gre_net *ign;
2012	int err;
2013
2014	ip6gre_netlink_parms(data, &nt->parms);
2015	ign = net_generic(net, ip6gre_net_id);
2016
2017	if (nt->parms.collect_md) {
2018		if (rtnl_dereference(ign->collect_md_tun))
2019			return -EEXIST;
2020	} else {
2021		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2022			return -EEXIST;
2023	}
2024
2025	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2026	if (!err) {
2027		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2028		ip6gre_tunnel_link_md(ign, nt);
2029		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2030	}
2031	return err;
2032}
2033
2034static struct ip6_tnl *
2035ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2036			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2037			 struct netlink_ext_ack *extack)
2038{
2039	struct ip6_tnl *t, *nt = netdev_priv(dev);
2040	struct net *net = nt->net;
2041	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2042	struct ip_tunnel_encap ipencap;
2043
2044	if (dev == ign->fb_tunnel_dev)
2045		return ERR_PTR(-EINVAL);
2046
2047	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2048		int err = ip6_tnl_encap_setup(nt, &ipencap);
2049
2050		if (err < 0)
2051			return ERR_PTR(err);
2052	}
2053
2054	ip6gre_netlink_parms(data, p_p);
2055
2056	t = ip6gre_tunnel_locate(net, p_p, 0);
2057
2058	if (t) {
2059		if (t->dev != dev)
2060			return ERR_PTR(-EEXIST);
2061	} else {
2062		t = nt;
2063	}
2064
2065	return t;
2066}
2067
2068static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2069			     struct nlattr *data[],
2070			     struct netlink_ext_ack *extack)
2071{
2072	struct ip6_tnl *t = netdev_priv(dev);
2073	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2074	struct __ip6_tnl_parm p;
2075
2076	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2077	if (IS_ERR(t))
2078		return PTR_ERR(t);
2079
2080	ip6gre_tunnel_unlink_md(ign, t);
2081	ip6gre_tunnel_unlink(ign, t);
2082	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2083	ip6gre_tunnel_link_md(ign, t);
2084	ip6gre_tunnel_link(ign, t);
2085	return 0;
2086}
2087
2088static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2089{
2090	struct net *net = dev_net(dev);
2091	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2092
2093	if (dev != ign->fb_tunnel_dev)
2094		unregister_netdevice_queue(dev, head);
2095}
2096
2097static size_t ip6gre_get_size(const struct net_device *dev)
2098{
2099	return
2100		/* IFLA_GRE_LINK */
2101		nla_total_size(4) +
2102		/* IFLA_GRE_IFLAGS */
2103		nla_total_size(2) +
2104		/* IFLA_GRE_OFLAGS */
2105		nla_total_size(2) +
2106		/* IFLA_GRE_IKEY */
2107		nla_total_size(4) +
2108		/* IFLA_GRE_OKEY */
2109		nla_total_size(4) +
2110		/* IFLA_GRE_LOCAL */
2111		nla_total_size(sizeof(struct in6_addr)) +
2112		/* IFLA_GRE_REMOTE */
2113		nla_total_size(sizeof(struct in6_addr)) +
2114		/* IFLA_GRE_TTL */
2115		nla_total_size(1) +
2116		/* IFLA_GRE_ENCAP_LIMIT */
2117		nla_total_size(1) +
2118		/* IFLA_GRE_FLOWINFO */
2119		nla_total_size(4) +
2120		/* IFLA_GRE_FLAGS */
2121		nla_total_size(4) +
2122		/* IFLA_GRE_ENCAP_TYPE */
2123		nla_total_size(2) +
2124		/* IFLA_GRE_ENCAP_FLAGS */
2125		nla_total_size(2) +
2126		/* IFLA_GRE_ENCAP_SPORT */
2127		nla_total_size(2) +
2128		/* IFLA_GRE_ENCAP_DPORT */
2129		nla_total_size(2) +
2130		/* IFLA_GRE_COLLECT_METADATA */
2131		nla_total_size(0) +
2132		/* IFLA_GRE_FWMARK */
2133		nla_total_size(4) +
2134		/* IFLA_GRE_ERSPAN_INDEX */
2135		nla_total_size(4) +
2136		0;
2137}
2138
2139static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2140{
2141	struct ip6_tnl *t = netdev_priv(dev);
2142	struct __ip6_tnl_parm *p = &t->parms;
2143	__be16 o_flags = p->o_flags;
2144
2145	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2146		if (!p->collect_md)
2147			o_flags |= TUNNEL_KEY;
2148
2149		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2150			goto nla_put_failure;
2151
2152		if (p->erspan_ver == 1) {
2153			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2154				goto nla_put_failure;
2155		} else {
2156			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2157				goto nla_put_failure;
2158			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2159				goto nla_put_failure;
2160		}
2161	}
2162
2163	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2164	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2165			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2166	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2167			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2168	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2169	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2170	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2171	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2172	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2173	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2174	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2175	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2176	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2177		goto nla_put_failure;
2178
2179	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2180			t->encap.type) ||
2181	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2182			 t->encap.sport) ||
2183	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2184			 t->encap.dport) ||
2185	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2186			t->encap.flags))
2187		goto nla_put_failure;
2188
2189	if (p->collect_md) {
2190		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2191			goto nla_put_failure;
2192	}
2193
2194	return 0;
2195
2196nla_put_failure:
2197	return -EMSGSIZE;
2198}
2199
2200static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2201	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2202	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2203	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2204	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2205	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2206	[IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2207	[IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2208	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2209	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2210	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2211	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2212	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2213	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2214	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2215	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2216	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2217	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2218	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2219	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2220	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2221	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2222};
2223
2224static void ip6erspan_tap_setup(struct net_device *dev)
2225{
2226	ether_setup(dev);
2227
2228	dev->max_mtu = 0;
2229	dev->netdev_ops = &ip6erspan_netdev_ops;
2230	dev->needs_free_netdev = true;
2231	dev->priv_destructor = ip6gre_dev_free;
2232
2233	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2234	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2235	netif_keep_dst(dev);
2236}
2237
2238static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2239			     struct nlattr *tb[], struct nlattr *data[],
2240			     struct netlink_ext_ack *extack)
2241{
2242	struct ip6_tnl *nt = netdev_priv(dev);
2243	struct net *net = dev_net(dev);
2244	struct ip6gre_net *ign;
2245	int err;
2246
2247	ip6gre_netlink_parms(data, &nt->parms);
2248	ip6erspan_set_version(data, &nt->parms);
2249	ign = net_generic(net, ip6gre_net_id);
2250
2251	if (nt->parms.collect_md) {
2252		if (rtnl_dereference(ign->collect_md_tun_erspan))
2253			return -EEXIST;
2254	} else {
2255		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2256			return -EEXIST;
2257	}
2258
2259	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2260	if (!err) {
2261		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2262		ip6erspan_tunnel_link_md(ign, nt);
2263		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2264	}
2265	return err;
2266}
2267
2268static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2269{
2270	ip6gre_tnl_link_config_common(t);
2271	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2272}
2273
2274static int ip6erspan_tnl_change(struct ip6_tnl *t,
2275				const struct __ip6_tnl_parm *p, int set_mtu)
2276{
2277	ip6gre_tnl_copy_tnl_parm(t, p);
2278	ip6erspan_tnl_link_config(t, set_mtu);
2279	return 0;
2280}
2281
2282static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2283				struct nlattr *data[],
2284				struct netlink_ext_ack *extack)
2285{
2286	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2287	struct __ip6_tnl_parm p;
2288	struct ip6_tnl *t;
2289
2290	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2291	if (IS_ERR(t))
2292		return PTR_ERR(t);
2293
2294	ip6erspan_set_version(data, &p);
2295	ip6gre_tunnel_unlink_md(ign, t);
2296	ip6gre_tunnel_unlink(ign, t);
2297	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2298	ip6erspan_tunnel_link_md(ign, t);
2299	ip6gre_tunnel_link(ign, t);
2300	return 0;
2301}
2302
2303static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2304	.kind		= "ip6gre",
2305	.maxtype	= IFLA_GRE_MAX,
2306	.policy		= ip6gre_policy,
2307	.priv_size	= sizeof(struct ip6_tnl),
2308	.setup		= ip6gre_tunnel_setup,
2309	.validate	= ip6gre_tunnel_validate,
2310	.newlink	= ip6gre_newlink,
2311	.changelink	= ip6gre_changelink,
2312	.dellink	= ip6gre_dellink,
2313	.get_size	= ip6gre_get_size,
2314	.fill_info	= ip6gre_fill_info,
2315	.get_link_net	= ip6_tnl_get_link_net,
2316};
2317
2318static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2319	.kind		= "ip6gretap",
2320	.maxtype	= IFLA_GRE_MAX,
2321	.policy		= ip6gre_policy,
2322	.priv_size	= sizeof(struct ip6_tnl),
2323	.setup		= ip6gre_tap_setup,
2324	.validate	= ip6gre_tap_validate,
2325	.newlink	= ip6gre_newlink,
2326	.changelink	= ip6gre_changelink,
2327	.get_size	= ip6gre_get_size,
2328	.fill_info	= ip6gre_fill_info,
2329	.get_link_net	= ip6_tnl_get_link_net,
2330};
2331
2332static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2333	.kind		= "ip6erspan",
2334	.maxtype	= IFLA_GRE_MAX,
2335	.policy		= ip6gre_policy,
2336	.priv_size	= sizeof(struct ip6_tnl),
2337	.setup		= ip6erspan_tap_setup,
2338	.validate	= ip6erspan_tap_validate,
2339	.newlink	= ip6erspan_newlink,
2340	.changelink	= ip6erspan_changelink,
2341	.get_size	= ip6gre_get_size,
2342	.fill_info	= ip6gre_fill_info,
2343	.get_link_net	= ip6_tnl_get_link_net,
2344};
2345
2346/*
2347 *	And now the modules code and kernel interface.
2348 */
2349
2350static int __init ip6gre_init(void)
2351{
2352	int err;
2353
2354	pr_info("GRE over IPv6 tunneling driver\n");
2355
2356	err = register_pernet_device(&ip6gre_net_ops);
2357	if (err < 0)
2358		return err;
2359
2360	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2361	if (err < 0) {
2362		pr_info("%s: can't add protocol\n", __func__);
2363		goto add_proto_failed;
2364	}
2365
2366	err = rtnl_link_register(&ip6gre_link_ops);
2367	if (err < 0)
2368		goto rtnl_link_failed;
2369
2370	err = rtnl_link_register(&ip6gre_tap_ops);
2371	if (err < 0)
2372		goto tap_ops_failed;
2373
2374	err = rtnl_link_register(&ip6erspan_tap_ops);
2375	if (err < 0)
2376		goto erspan_link_failed;
2377
2378out:
2379	return err;
2380
2381erspan_link_failed:
2382	rtnl_link_unregister(&ip6gre_tap_ops);
2383tap_ops_failed:
2384	rtnl_link_unregister(&ip6gre_link_ops);
2385rtnl_link_failed:
2386	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2387add_proto_failed:
2388	unregister_pernet_device(&ip6gre_net_ops);
2389	goto out;
2390}
2391
2392static void __exit ip6gre_fini(void)
2393{
2394	rtnl_link_unregister(&ip6gre_tap_ops);
2395	rtnl_link_unregister(&ip6gre_link_ops);
2396	rtnl_link_unregister(&ip6erspan_tap_ops);
2397	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2398	unregister_pernet_device(&ip6gre_net_ops);
2399}
2400
2401module_init(ip6gre_init);
2402module_exit(ip6gre_fini);
2403MODULE_LICENSE("GPL");
2404MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2405MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2406MODULE_ALIAS_RTNL_LINK("ip6gre");
2407MODULE_ALIAS_RTNL_LINK("ip6gretap");
2408MODULE_ALIAS_RTNL_LINK("ip6erspan");
2409MODULE_ALIAS_NETDEV("ip6gre0");