1// SPDX-License-Identifier: GPL-2.0-only
   2#include <linux/types.h>
   3#include <linux/skbuff.h>
   4#include <linux/socket.h>
   5#include <linux/sysctl.h>
   6#include <linux/net.h>
   7#include <linux/module.h>
   8#include <linux/if_arp.h>
   9#include <linux/ipv6.h>
  10#include <linux/mpls.h>
  11#include <linux/netconf.h>
  12#include <linux/nospec.h>
  13#include <linux/vmalloc.h>
  14#include <linux/percpu.h>
  15#include <net/gso.h>
  16#include <net/ip.h>
  17#include <net/dst.h>
  18#include <net/sock.h>
  19#include <net/arp.h>
  20#include <net/ip_fib.h>
  21#include <net/netevent.h>
  22#include <net/ip_tunnels.h>
  23#include <net/netns/generic.h>
  24#if IS_ENABLED(CONFIG_IPV6)
  25#include <net/ipv6.h>
 
  26#endif
  27#include <net/ipv6_stubs.h>
  28#include <net/rtnh.h>
  29#include "internal.h"
  30
  31/* max memory we will use for mpls_route */
  32#define MAX_MPLS_ROUTE_MEM	4096
  33
  34/* Maximum number of labels to look ahead at when selecting a path of
  35 * a multipath route
  36 */
  37#define MAX_MP_SELECT_LABELS 4
  38
  39#define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1)
  40
 
  41static int label_limit = (1 << 20) - 1;
  42static int ttl_max = 255;
  43
  44#if IS_ENABLED(CONFIG_NET_IP_TUNNEL)
  45static size_t ipgre_mpls_encap_hlen(struct ip_tunnel_encap *e)
  46{
  47	return sizeof(struct mpls_shim_hdr);
  48}
  49
  50static const struct ip_tunnel_encap_ops mpls_iptun_ops = {
  51	.encap_hlen	= ipgre_mpls_encap_hlen,
  52};
  53
  54static int ipgre_tunnel_encap_add_mpls_ops(void)
  55{
  56	return ip_tunnel_encap_add_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS);
  57}
  58
  59static void ipgre_tunnel_encap_del_mpls_ops(void)
  60{
  61	ip_tunnel_encap_del_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS);
  62}
  63#else
  64static int ipgre_tunnel_encap_add_mpls_ops(void)
  65{
  66	return 0;
  67}
  68
  69static void ipgre_tunnel_encap_del_mpls_ops(void)
  70{
  71}
  72#endif
  73
  74static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
  75		       struct nlmsghdr *nlh, struct net *net, u32 portid,
  76		       unsigned int nlm_flags);
  77
  78static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
  79{
  80	struct mpls_route *rt = NULL;
  81
  82	if (index < net->mpls.platform_labels) {
  83		struct mpls_route __rcu **platform_label =
  84			rcu_dereference(net->mpls.platform_label);
  85		rt = rcu_dereference(platform_label[index]);
  86	}
  87	return rt;
  88}
  89
 
 
 
 
 
  90bool mpls_output_possible(const struct net_device *dev)
  91{
  92	return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
  93}
  94EXPORT_SYMBOL_GPL(mpls_output_possible);
  95
  96static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh)
  97{
  98	return (u8 *)nh + rt->rt_via_offset;
 
 
 
  99}
 100
 101static const u8 *mpls_nh_via(const struct mpls_route *rt,
 102			     const struct mpls_nh *nh)
 103{
 104	return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh);
 105}
 106
 107static unsigned int mpls_nh_header_size(const struct mpls_nh *nh)
 108{
 109	/* The size of the layer 2.5 labels to be added for this route */
 110	return nh->nh_labels * sizeof(struct mpls_shim_hdr);
 111}
 112
 113unsigned int mpls_dev_mtu(const struct net_device *dev)
 114{
 115	/* The amount of data the layer 2 frame can hold */
 116	return dev->mtu;
 117}
 118EXPORT_SYMBOL_GPL(mpls_dev_mtu);
 119
 120bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
 121{
 122	if (skb->len <= mtu)
 123		return false;
 124
 125	if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
 126		return false;
 127
 128	return true;
 129}
 130EXPORT_SYMBOL_GPL(mpls_pkt_too_big);
 131
 132void mpls_stats_inc_outucastpkts(struct net_device *dev,
 133				 const struct sk_buff *skb)
 134{
 135	struct mpls_dev *mdev;
 136
 137	if (skb->protocol == htons(ETH_P_MPLS_UC)) {
 138		mdev = mpls_dev_get(dev);
 139		if (mdev)
 140			MPLS_INC_STATS_LEN(mdev, skb->len,
 141					   tx_packets,
 142					   tx_bytes);
 143	} else if (skb->protocol == htons(ETH_P_IP)) {
 144		IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
 145#if IS_ENABLED(CONFIG_IPV6)
 146	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 147		struct inet6_dev *in6dev = __in6_dev_get(dev);
 148
 149		if (in6dev)
 150			IP6_UPD_PO_STATS(dev_net(dev), in6dev,
 151					 IPSTATS_MIB_OUT, skb->len);
 152#endif
 153	}
 154}
 155EXPORT_SYMBOL_GPL(mpls_stats_inc_outucastpkts);
 156
 157static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb)
 158{
 159	struct mpls_entry_decoded dec;
 160	unsigned int mpls_hdr_len = 0;
 161	struct mpls_shim_hdr *hdr;
 162	bool eli_seen = false;
 163	int label_index;
 164	u32 hash = 0;
 165
 166	for (label_index = 0; label_index < MAX_MP_SELECT_LABELS;
 167	     label_index++) {
 168		mpls_hdr_len += sizeof(*hdr);
 169		if (!pskb_may_pull(skb, mpls_hdr_len))
 170			break;
 171
 172		/* Read and decode the current label */
 173		hdr = mpls_hdr(skb) + label_index;
 174		dec = mpls_entry_decode(hdr);
 175
 176		/* RFC6790 - reserved labels MUST NOT be used as keys
 177		 * for the load-balancing function
 178		 */
 179		if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) {
 180			hash = jhash_1word(dec.label, hash);
 181
 182			/* The entropy label follows the entropy label
 183			 * indicator, so this means that the entropy
 184			 * label was just added to the hash - no need to
 185			 * go any deeper either in the label stack or in the
 186			 * payload
 187			 */
 188			if (eli_seen)
 189				break;
 190		} else if (dec.label == MPLS_LABEL_ENTROPY) {
 191			eli_seen = true;
 192		}
 193
 194		if (!dec.bos)
 195			continue;
 196
 197		/* found bottom label; does skb have room for a header? */
 198		if (pskb_may_pull(skb, mpls_hdr_len + sizeof(struct iphdr))) {
 199			const struct iphdr *v4hdr;
 200
 201			v4hdr = (const struct iphdr *)(hdr + 1);
 202			if (v4hdr->version == 4) {
 203				hash = jhash_3words(ntohl(v4hdr->saddr),
 204						    ntohl(v4hdr->daddr),
 205						    v4hdr->protocol, hash);
 206			} else if (v4hdr->version == 6 &&
 207				   pskb_may_pull(skb, mpls_hdr_len +
 208						 sizeof(struct ipv6hdr))) {
 209				const struct ipv6hdr *v6hdr;
 210
 211				v6hdr = (const struct ipv6hdr *)(hdr + 1);
 212				hash = __ipv6_addr_jhash(&v6hdr->saddr, hash);
 213				hash = __ipv6_addr_jhash(&v6hdr->daddr, hash);
 214				hash = jhash_1word(v6hdr->nexthdr, hash);
 215			}
 216		}
 217
 218		break;
 219	}
 220
 221	return hash;
 222}
 223
 224static struct mpls_nh *mpls_get_nexthop(struct mpls_route *rt, u8 index)
 225{
 226	return (struct mpls_nh *)((u8 *)rt->rt_nh + index * rt->rt_nh_size);
 227}
 228
 229/* number of alive nexthops (rt->rt_nhn_alive) and the flags for
 230 * a next hop (nh->nh_flags) are modified by netdev event handlers.
 231 * Since those fields can change at any moment, use READ_ONCE to
 232 * access both.
 233 */
 234static const struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
 235						   struct sk_buff *skb)
 236{
 
 237	u32 hash = 0;
 238	int nh_index = 0;
 239	int n = 0;
 240	u8 alive;
 241
 242	/* No need to look further into packet if there's only
 243	 * one path
 244	 */
 245	if (rt->rt_nhn == 1)
 246		return rt->rt_nh;
 247
 248	alive = READ_ONCE(rt->rt_nhn_alive);
 249	if (alive == 0)
 250		return NULL;
 251
 252	hash = mpls_multipath_hash(rt, skb);
 253	nh_index = hash % alive;
 254	if (alive == rt->rt_nhn)
 255		goto out;
 256	for_nexthops(rt) {
 257		unsigned int nh_flags = READ_ONCE(nh->nh_flags);
 258
 259		if (nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
 260			continue;
 261		if (n == nh_index)
 262			return nh;
 263		n++;
 264	} endfor_nexthops(rt);
 265
 266out:
 267	return mpls_get_nexthop(rt, nh_index);
 268}
 269
 270static bool mpls_egress(struct net *net, struct mpls_route *rt,
 271			struct sk_buff *skb, struct mpls_entry_decoded dec)
 272{
 273	enum mpls_payload_type payload_type;
 274	bool success = false;
 275
 276	/* The IPv4 code below accesses through the IPv4 header
 277	 * checksum, which is 12 bytes into the packet.
 278	 * The IPv6 code below accesses through the IPv6 hop limit
 279	 * which is 8 bytes into the packet.
 280	 *
 281	 * For all supported cases there should always be at least 12
 282	 * bytes of packet data present.  The IPv4 header is 20 bytes
 283	 * without options and the IPv6 header is always 40 bytes
 284	 * long.
 285	 */
 286	if (!pskb_may_pull(skb, 12))
 287		return false;
 288
 289	payload_type = rt->rt_payload_type;
 290	if (payload_type == MPT_UNSPEC)
 291		payload_type = ip_hdr(skb)->version;
 292
 293	switch (payload_type) {
 294	case MPT_IPV4: {
 295		struct iphdr *hdr4 = ip_hdr(skb);
 296		u8 new_ttl;
 297		skb->protocol = htons(ETH_P_IP);
 298
 299		/* If propagating TTL, take the decremented TTL from
 300		 * the incoming MPLS header, otherwise decrement the
 301		 * TTL, but only if not 0 to avoid underflow.
 302		 */
 303		if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
 304		    (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
 305		     net->mpls.ip_ttl_propagate))
 306			new_ttl = dec.ttl;
 307		else
 308			new_ttl = hdr4->ttl ? hdr4->ttl - 1 : 0;
 309
 310		csum_replace2(&hdr4->check,
 311			      htons(hdr4->ttl << 8),
 312			      htons(new_ttl << 8));
 313		hdr4->ttl = new_ttl;
 314		success = true;
 315		break;
 316	}
 317	case MPT_IPV6: {
 318		struct ipv6hdr *hdr6 = ipv6_hdr(skb);
 319		skb->protocol = htons(ETH_P_IPV6);
 320
 321		/* If propagating TTL, take the decremented TTL from
 322		 * the incoming MPLS header, otherwise decrement the
 323		 * hop limit, but only if not 0 to avoid underflow.
 324		 */
 325		if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
 326		    (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
 327		     net->mpls.ip_ttl_propagate))
 328			hdr6->hop_limit = dec.ttl;
 329		else if (hdr6->hop_limit)
 330			hdr6->hop_limit = hdr6->hop_limit - 1;
 331		success = true;
 332		break;
 333	}
 334	case MPT_UNSPEC:
 335		/* Should have decided which protocol it is by now */
 336		break;
 337	}
 338
 339	return success;
 340}
 341
 342static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
 343			struct packet_type *pt, struct net_device *orig_dev)
 344{
 345	struct net *net = dev_net(dev);
 346	struct mpls_shim_hdr *hdr;
 347	const struct mpls_nh *nh;
 348	struct mpls_route *rt;
 
 349	struct mpls_entry_decoded dec;
 350	struct net_device *out_dev;
 351	struct mpls_dev *out_mdev;
 352	struct mpls_dev *mdev;
 353	unsigned int hh_len;
 354	unsigned int new_header_size;
 355	unsigned int mtu;
 356	int err;
 357
 358	/* Careful this entire function runs inside of an rcu critical section */
 359
 360	mdev = mpls_dev_get(dev);
 361	if (!mdev)
 362		goto drop;
 363
 364	MPLS_INC_STATS_LEN(mdev, skb->len, rx_packets,
 365			   rx_bytes);
 366
 367	if (!mdev->input_enabled) {
 368		MPLS_INC_STATS(mdev, rx_dropped);
 369		goto drop;
 370	}
 371
 372	if (skb->pkt_type != PACKET_HOST)
 373		goto err;
 374
 375	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 376		goto err;
 377
 378	if (!pskb_may_pull(skb, sizeof(*hdr)))
 379		goto err;
 380
 381	skb_dst_drop(skb);
 382
 383	/* Read and decode the label */
 384	hdr = mpls_hdr(skb);
 385	dec = mpls_entry_decode(hdr);
 386
 387	rt = mpls_route_input_rcu(net, dec.label);
 388	if (!rt) {
 389		MPLS_INC_STATS(mdev, rx_noroute);
 390		goto drop;
 391	}
 392
 393	nh = mpls_select_multipath(rt, skb);
 394	if (!nh)
 395		goto err;
 
 
 
 
 
 396
 397	/* Pop the label */
 398	skb_pull(skb, sizeof(*hdr));
 399	skb_reset_network_header(skb);
 400
 401	skb_orphan(skb);
 402
 403	if (skb_warn_if_lro(skb))
 404		goto err;
 405
 406	skb_forward_csum(skb);
 407
 408	/* Verify ttl is valid */
 409	if (dec.ttl <= 1)
 410		goto err;
 411
 412	/* Find the output device */
 413	out_dev = nh->nh_dev;
 414	if (!mpls_output_possible(out_dev))
 415		goto tx_err;
 416
 417	/* Verify the destination can hold the packet */
 418	new_header_size = mpls_nh_header_size(nh);
 419	mtu = mpls_dev_mtu(out_dev);
 420	if (mpls_pkt_too_big(skb, mtu - new_header_size))
 421		goto tx_err;
 422
 423	hh_len = LL_RESERVED_SPACE(out_dev);
 424	if (!out_dev->header_ops)
 425		hh_len = 0;
 426
 427	/* Ensure there is enough space for the headers in the skb */
 428	if (skb_cow(skb, hh_len + new_header_size))
 429		goto tx_err;
 430
 431	skb->dev = out_dev;
 432	skb->protocol = htons(ETH_P_MPLS_UC);
 433
 434	dec.ttl -= 1;
 435	if (unlikely(!new_header_size && dec.bos)) {
 436		/* Penultimate hop popping */
 437		if (!mpls_egress(dev_net(out_dev), rt, skb, dec))
 438			goto err;
 439	} else {
 440		bool bos;
 441		int i;
 442		skb_push(skb, new_header_size);
 443		skb_reset_network_header(skb);
 444		/* Push the new labels */
 445		hdr = mpls_hdr(skb);
 446		bos = dec.bos;
 447		for (i = nh->nh_labels - 1; i >= 0; i--) {
 448			hdr[i] = mpls_entry_encode(nh->nh_label[i],
 449						   dec.ttl, 0, bos);
 450			bos = false;
 451		}
 452	}
 453
 454	mpls_stats_inc_outucastpkts(out_dev, skb);
 455
 456	/* If via wasn't specified then send out using device address */
 457	if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC)
 458		err = neigh_xmit(NEIGH_LINK_TABLE, out_dev,
 459				 out_dev->dev_addr, skb);
 460	else
 461		err = neigh_xmit(nh->nh_via_table, out_dev,
 462				 mpls_nh_via(rt, nh), skb);
 463	if (err)
 464		net_dbg_ratelimited("%s: packet transmission failed: %d\n",
 465				    __func__, err);
 466	return 0;
 467
 468tx_err:
 469	out_mdev = out_dev ? mpls_dev_get(out_dev) : NULL;
 470	if (out_mdev)
 471		MPLS_INC_STATS(out_mdev, tx_errors);
 472	goto drop;
 473err:
 474	MPLS_INC_STATS(mdev, rx_errors);
 475drop:
 476	kfree_skb(skb);
 477	return NET_RX_DROP;
 478}
 479
 480static struct packet_type mpls_packet_type __read_mostly = {
 481	.type = cpu_to_be16(ETH_P_MPLS_UC),
 482	.func = mpls_forward,
 483};
 484
 485static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
 486	[RTA_DST]		= { .type = NLA_U32 },
 487	[RTA_OIF]		= { .type = NLA_U32 },
 488	[RTA_TTL_PROPAGATE]	= { .type = NLA_U8 },
 489};
 490
 491struct mpls_route_config {
 492	u32			rc_protocol;
 493	u32			rc_ifindex;
 494	u8			rc_via_table;
 495	u8			rc_via_alen;
 496	u8			rc_via[MAX_VIA_ALEN];
 497	u32			rc_label;
 498	u8			rc_ttl_propagate;
 499	u8			rc_output_labels;
 500	u32			rc_output_label[MAX_NEW_LABELS];
 501	u32			rc_nlflags;
 502	enum mpls_payload_type	rc_payload_type;
 503	struct nl_info		rc_nlinfo;
 504	struct rtnexthop	*rc_mp;
 505	int			rc_mp_len;
 506};
 507
 508/* all nexthops within a route have the same size based on max
 509 * number of labels and max via length for a hop
 510 */
 511static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen, u8 max_labels)
 512{
 513	u8 nh_size = MPLS_NH_SIZE(max_labels, max_alen);
 514	struct mpls_route *rt;
 515	size_t size;
 516
 517	size = sizeof(*rt) + num_nh * nh_size;
 518	if (size > MAX_MPLS_ROUTE_MEM)
 519		return ERR_PTR(-EINVAL);
 520
 521	rt = kzalloc(size, GFP_KERNEL);
 522	if (!rt)
 523		return ERR_PTR(-ENOMEM);
 524
 525	rt->rt_nhn = num_nh;
 526	rt->rt_nhn_alive = num_nh;
 527	rt->rt_nh_size = nh_size;
 528	rt->rt_via_offset = MPLS_NH_VIA_OFF(max_labels);
 529
 530	return rt;
 531}
 532
 533static void mpls_rt_free(struct mpls_route *rt)
 534{
 535	if (rt)
 536		kfree_rcu(rt, rt_rcu);
 537}
 538
 539static void mpls_notify_route(struct net *net, unsigned index,
 540			      struct mpls_route *old, struct mpls_route *new,
 541			      const struct nl_info *info)
 542{
 543	struct nlmsghdr *nlh = info ? info->nlh : NULL;
 544	unsigned portid = info ? info->portid : 0;
 545	int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
 546	struct mpls_route *rt = new ? new : old;
 547	unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
 548	/* Ignore reserved labels for now */
 549	if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED))
 550		rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
 551}
 552
 553static void mpls_route_update(struct net *net, unsigned index,
 554			      struct mpls_route *new,
 555			      const struct nl_info *info)
 556{
 557	struct mpls_route __rcu **platform_label;
 558	struct mpls_route *rt;
 559
 560	ASSERT_RTNL();
 561
 562	platform_label = rtnl_dereference(net->mpls.platform_label);
 563	rt = rtnl_dereference(platform_label[index]);
 564	rcu_assign_pointer(platform_label[index], new);
 565
 566	mpls_notify_route(net, index, rt, new, info);
 567
 568	/* If we removed a route free it now */
 569	mpls_rt_free(rt);
 570}
 571
 572static unsigned find_free_label(struct net *net)
 573{
 574	struct mpls_route __rcu **platform_label;
 575	size_t platform_labels;
 576	unsigned index;
 577
 578	platform_label = rtnl_dereference(net->mpls.platform_label);
 579	platform_labels = net->mpls.platform_labels;
 580	for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
 581	     index++) {
 582		if (!rtnl_dereference(platform_label[index]))
 583			return index;
 584	}
 585	return LABEL_NOT_SPECIFIED;
 586}
 587
 588#if IS_ENABLED(CONFIG_INET)
 589static struct net_device *inet_fib_lookup_dev(struct net *net,
 590					      const void *addr)
 591{
 592	struct net_device *dev;
 593	struct rtable *rt;
 594	struct in_addr daddr;
 595
 596	memcpy(&daddr, addr, sizeof(struct in_addr));
 597	rt = ip_route_output(net, daddr.s_addr, 0, 0, 0);
 598	if (IS_ERR(rt))
 599		return ERR_CAST(rt);
 600
 601	dev = rt->dst.dev;
 602	dev_hold(dev);
 603
 604	ip_rt_put(rt);
 605
 606	return dev;
 607}
 608#else
 609static struct net_device *inet_fib_lookup_dev(struct net *net,
 610					      const void *addr)
 611{
 612	return ERR_PTR(-EAFNOSUPPORT);
 613}
 614#endif
 615
 616#if IS_ENABLED(CONFIG_IPV6)
 617static struct net_device *inet6_fib_lookup_dev(struct net *net,
 618					       const void *addr)
 619{
 620	struct net_device *dev;
 621	struct dst_entry *dst;
 622	struct flowi6 fl6;
 
 623
 624	if (!ipv6_stub)
 625		return ERR_PTR(-EAFNOSUPPORT);
 626
 627	memset(&fl6, 0, sizeof(fl6));
 628	memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
 629	dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
 630	if (IS_ERR(dst))
 631		return ERR_CAST(dst);
 632
 633	dev = dst->dev;
 634	dev_hold(dev);
 635	dst_release(dst);
 636
 637	return dev;
 638}
 639#else
 640static struct net_device *inet6_fib_lookup_dev(struct net *net,
 641					       const void *addr)
 642{
 643	return ERR_PTR(-EAFNOSUPPORT);
 644}
 645#endif
 646
 647static struct net_device *find_outdev(struct net *net,
 648				      struct mpls_route *rt,
 649				      struct mpls_nh *nh, int oif)
 650{
 651	struct net_device *dev = NULL;
 652
 653	if (!oif) {
 654		switch (nh->nh_via_table) {
 655		case NEIGH_ARP_TABLE:
 656			dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh));
 657			break;
 658		case NEIGH_ND_TABLE:
 659			dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh));
 660			break;
 661		case NEIGH_LINK_TABLE:
 662			break;
 663		}
 664	} else {
 665		dev = dev_get_by_index(net, oif);
 666	}
 667
 668	if (!dev)
 669		return ERR_PTR(-ENODEV);
 670
 671	if (IS_ERR(dev))
 672		return dev;
 673
 674	/* The caller is holding rtnl anyways, so release the dev reference */
 675	dev_put(dev);
 676
 677	return dev;
 678}
 679
 680static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt,
 681			      struct mpls_nh *nh, int oif)
 682{
 683	struct net_device *dev = NULL;
 684	int err = -ENODEV;
 685
 686	dev = find_outdev(net, rt, nh, oif);
 687	if (IS_ERR(dev)) {
 688		err = PTR_ERR(dev);
 689		dev = NULL;
 690		goto errout;
 691	}
 692
 693	/* Ensure this is a supported device */
 694	err = -EINVAL;
 695	if (!mpls_dev_get(dev))
 696		goto errout;
 697
 698	if ((nh->nh_via_table == NEIGH_LINK_TABLE) &&
 699	    (dev->addr_len != nh->nh_via_alen))
 700		goto errout;
 701
 702	nh->nh_dev = dev;
 703
 704	if (!(dev->flags & IFF_UP)) {
 705		nh->nh_flags |= RTNH_F_DEAD;
 706	} else {
 707		unsigned int flags;
 708
 709		flags = dev_get_flags(dev);
 710		if (!(flags & (IFF_RUNNING | IFF_LOWER_UP)))
 711			nh->nh_flags |= RTNH_F_LINKDOWN;
 712	}
 713
 714	return 0;
 715
 716errout:
 717	return err;
 718}
 719
 720static int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table,
 721		       u8 via_addr[], struct netlink_ext_ack *extack)
 722{
 723	struct rtvia *via = nla_data(nla);
 724	int err = -EINVAL;
 725	int alen;
 726
 727	if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) {
 728		NL_SET_ERR_MSG_ATTR(extack, nla,
 729				    "Invalid attribute length for RTA_VIA");
 730		goto errout;
 731	}
 732	alen = nla_len(nla) -
 733			offsetof(struct rtvia, rtvia_addr);
 734	if (alen > MAX_VIA_ALEN) {
 735		NL_SET_ERR_MSG_ATTR(extack, nla,
 736				    "Invalid address length for RTA_VIA");
 737		goto errout;
 738	}
 739
 740	/* Validate the address family */
 741	switch (via->rtvia_family) {
 742	case AF_PACKET:
 743		*via_table = NEIGH_LINK_TABLE;
 744		break;
 745	case AF_INET:
 746		*via_table = NEIGH_ARP_TABLE;
 747		if (alen != 4)
 748			goto errout;
 749		break;
 750	case AF_INET6:
 751		*via_table = NEIGH_ND_TABLE;
 752		if (alen != 16)
 753			goto errout;
 754		break;
 755	default:
 756		/* Unsupported address family */
 757		goto errout;
 758	}
 759
 760	memcpy(via_addr, via->rtvia_addr, alen);
 761	*via_alen = alen;
 762	err = 0;
 763
 764errout:
 765	return err;
 766}
 767
 768static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg,
 769				  struct mpls_route *rt)
 770{
 771	struct net *net = cfg->rc_nlinfo.nl_net;
 772	struct mpls_nh *nh = rt->rt_nh;
 773	int err;
 774	int i;
 775
 776	if (!nh)
 777		return -ENOMEM;
 778
 
 
 
 
 
 779	nh->nh_labels = cfg->rc_output_labels;
 780	for (i = 0; i < nh->nh_labels; i++)
 781		nh->nh_label[i] = cfg->rc_output_label[i];
 782
 783	nh->nh_via_table = cfg->rc_via_table;
 784	memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen);
 785	nh->nh_via_alen = cfg->rc_via_alen;
 786
 787	err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex);
 788	if (err)
 789		goto errout;
 790
 791	if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
 792		rt->rt_nhn_alive--;
 793
 794	return 0;
 795
 796errout:
 797	return err;
 798}
 799
 800static int mpls_nh_build(struct net *net, struct mpls_route *rt,
 801			 struct mpls_nh *nh, int oif, struct nlattr *via,
 802			 struct nlattr *newdst, u8 max_labels,
 803			 struct netlink_ext_ack *extack)
 804{
 805	int err = -ENOMEM;
 806
 807	if (!nh)
 808		goto errout;
 809
 810	if (newdst) {
 811		err = nla_get_labels(newdst, max_labels, &nh->nh_labels,
 812				     nh->nh_label, extack);
 813		if (err)
 814			goto errout;
 815	}
 816
 817	if (via) {
 818		err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table,
 819				  __mpls_nh_via(rt, nh), extack);
 820		if (err)
 821			goto errout;
 822	} else {
 823		nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC;
 824	}
 825
 826	err = mpls_nh_assign_dev(net, rt, nh, oif);
 827	if (err)
 828		goto errout;
 829
 830	return 0;
 831
 832errout:
 833	return err;
 834}
 835
 836static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len,
 837			      u8 cfg_via_alen, u8 *max_via_alen,
 838			      u8 *max_labels)
 839{
 
 840	int remaining = len;
 841	u8 nhs = 0;
 
 
 
 
 842
 843	*max_via_alen = 0;
 844	*max_labels = 0;
 845
 846	while (rtnh_ok(rtnh, remaining)) {
 847		struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
 848		int attrlen;
 849		u8 n_labels = 0;
 850
 851		attrlen = rtnh_attrlen(rtnh);
 852		nla = nla_find(attrs, attrlen, RTA_VIA);
 853		if (nla && nla_len(nla) >=
 854		    offsetof(struct rtvia, rtvia_addr)) {
 855			int via_alen = nla_len(nla) -
 856				offsetof(struct rtvia, rtvia_addr);
 857
 858			if (via_alen <= MAX_VIA_ALEN)
 859				*max_via_alen = max_t(u16, *max_via_alen,
 860						      via_alen);
 861		}
 862
 863		nla = nla_find(attrs, attrlen, RTA_NEWDST);
 864		if (nla &&
 865		    nla_get_labels(nla, MAX_NEW_LABELS, &n_labels,
 866				   NULL, NULL) != 0)
 867			return 0;
 868
 869		*max_labels = max_t(u8, *max_labels, n_labels);
 870
 871		/* number of nexthops is tracked by a u8.
 872		 * Check for overflow.
 873		 */
 874		if (nhs == 255)
 875			return 0;
 876		nhs++;
 877
 878		rtnh = rtnh_next(rtnh, &remaining);
 879	}
 880
 881	/* leftover implies invalid nexthop configuration, discard it */
 882	return remaining > 0 ? 0 : nhs;
 883}
 884
 885static int mpls_nh_build_multi(struct mpls_route_config *cfg,
 886			       struct mpls_route *rt, u8 max_labels,
 887			       struct netlink_ext_ack *extack)
 888{
 889	struct rtnexthop *rtnh = cfg->rc_mp;
 890	struct nlattr *nla_via, *nla_newdst;
 891	int remaining = cfg->rc_mp_len;
 
 892	int err = 0;
 893	u8 nhs = 0;
 894
 895	change_nexthops(rt) {
 896		int attrlen;
 897
 898		nla_via = NULL;
 899		nla_newdst = NULL;
 900
 901		err = -EINVAL;
 902		if (!rtnh_ok(rtnh, remaining))
 903			goto errout;
 904
 905		/* neither weighted multipath nor any flags
 906		 * are supported
 907		 */
 908		if (rtnh->rtnh_hops || rtnh->rtnh_flags)
 909			goto errout;
 910
 911		attrlen = rtnh_attrlen(rtnh);
 912		if (attrlen > 0) {
 913			struct nlattr *attrs = rtnh_attrs(rtnh);
 914
 915			nla_via = nla_find(attrs, attrlen, RTA_VIA);
 916			nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST);
 917		}
 918
 919		err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh,
 920				    rtnh->rtnh_ifindex, nla_via, nla_newdst,
 921				    max_labels, extack);
 922		if (err)
 923			goto errout;
 924
 925		if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
 926			rt->rt_nhn_alive--;
 927
 928		rtnh = rtnh_next(rtnh, &remaining);
 929		nhs++;
 930	} endfor_nexthops(rt);
 931
 932	rt->rt_nhn = nhs;
 933
 934	return 0;
 935
 936errout:
 937	return err;
 938}
 939
 940static bool mpls_label_ok(struct net *net, unsigned int *index,
 941			  struct netlink_ext_ack *extack)
 942{
 943	bool is_ok = true;
 944
 945	/* Reserved labels may not be set */
 946	if (*index < MPLS_LABEL_FIRST_UNRESERVED) {
 947		NL_SET_ERR_MSG(extack,
 948			       "Invalid label - must be MPLS_LABEL_FIRST_UNRESERVED or higher");
 949		is_ok = false;
 950	}
 951
 952	/* The full 20 bit range may not be supported. */
 953	if (is_ok && *index >= net->mpls.platform_labels) {
 954		NL_SET_ERR_MSG(extack,
 955			       "Label >= configured maximum in platform_labels");
 956		is_ok = false;
 957	}
 958
 959	*index = array_index_nospec(*index, net->mpls.platform_labels);
 960	return is_ok;
 961}
 962
 963static int mpls_route_add(struct mpls_route_config *cfg,
 964			  struct netlink_ext_ack *extack)
 965{
 966	struct mpls_route __rcu **platform_label;
 967	struct net *net = cfg->rc_nlinfo.nl_net;
 968	struct mpls_route *rt, *old;
 969	int err = -EINVAL;
 970	u8 max_via_alen;
 971	unsigned index;
 972	u8 max_labels;
 973	u8 nhs;
 974
 975	index = cfg->rc_label;
 976
 977	/* If a label was not specified during insert pick one */
 978	if ((index == LABEL_NOT_SPECIFIED) &&
 979	    (cfg->rc_nlflags & NLM_F_CREATE)) {
 980		index = find_free_label(net);
 981	}
 982
 983	if (!mpls_label_ok(net, &index, extack))
 
 
 
 
 
 984		goto errout;
 985
 986	/* Append makes no sense with mpls */
 987	err = -EOPNOTSUPP;
 988	if (cfg->rc_nlflags & NLM_F_APPEND) {
 989		NL_SET_ERR_MSG(extack, "MPLS does not support route append");
 990		goto errout;
 991	}
 992
 993	err = -EEXIST;
 994	platform_label = rtnl_dereference(net->mpls.platform_label);
 995	old = rtnl_dereference(platform_label[index]);
 996	if ((cfg->rc_nlflags & NLM_F_EXCL) && old)
 997		goto errout;
 998
 999	err = -EEXIST;
1000	if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old)
1001		goto errout;
1002
1003	err = -ENOENT;
1004	if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old)
1005		goto errout;
1006
1007	err = -EINVAL;
1008	if (cfg->rc_mp) {
1009		nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len,
1010					  cfg->rc_via_alen, &max_via_alen,
1011					  &max_labels);
1012	} else {
1013		max_via_alen = cfg->rc_via_alen;
1014		max_labels = cfg->rc_output_labels;
1015		nhs = 1;
1016	}
1017
1018	if (nhs == 0) {
1019		NL_SET_ERR_MSG(extack, "Route does not contain a nexthop");
1020		goto errout;
1021	}
1022
1023	rt = mpls_rt_alloc(nhs, max_via_alen, max_labels);
1024	if (IS_ERR(rt)) {
1025		err = PTR_ERR(rt);
1026		goto errout;
1027	}
1028
1029	rt->rt_protocol = cfg->rc_protocol;
1030	rt->rt_payload_type = cfg->rc_payload_type;
1031	rt->rt_ttl_propagate = cfg->rc_ttl_propagate;
1032
1033	if (cfg->rc_mp)
1034		err = mpls_nh_build_multi(cfg, rt, max_labels, extack);
1035	else
1036		err = mpls_nh_build_from_cfg(cfg, rt);
1037	if (err)
1038		goto freert;
1039
1040	mpls_route_update(net, index, rt, &cfg->rc_nlinfo);
1041
1042	return 0;
1043
1044freert:
1045	mpls_rt_free(rt);
1046errout:
1047	return err;
1048}
1049
1050static int mpls_route_del(struct mpls_route_config *cfg,
1051			  struct netlink_ext_ack *extack)
1052{
1053	struct net *net = cfg->rc_nlinfo.nl_net;
1054	unsigned index;
1055	int err = -EINVAL;
1056
1057	index = cfg->rc_label;
1058
1059	if (!mpls_label_ok(net, &index, extack))
1060		goto errout;
1061
1062	mpls_route_update(net, index, NULL, &cfg->rc_nlinfo);
1063
1064	err = 0;
1065errout:
1066	return err;
1067}
1068
1069static void mpls_get_stats(struct mpls_dev *mdev,
1070			   struct mpls_link_stats *stats)
1071{
1072	struct mpls_pcpu_stats *p;
1073	int i;
1074
1075	memset(stats, 0, sizeof(*stats));
1076
1077	for_each_possible_cpu(i) {
1078		struct mpls_link_stats local;
1079		unsigned int start;
1080
1081		p = per_cpu_ptr(mdev->stats, i);
1082		do {
1083			start = u64_stats_fetch_begin(&p->syncp);
1084			local = p->stats;
1085		} while (u64_stats_fetch_retry(&p->syncp, start));
1086
1087		stats->rx_packets	+= local.rx_packets;
1088		stats->rx_bytes		+= local.rx_bytes;
1089		stats->tx_packets	+= local.tx_packets;
1090		stats->tx_bytes		+= local.tx_bytes;
1091		stats->rx_errors	+= local.rx_errors;
1092		stats->tx_errors	+= local.tx_errors;
1093		stats->rx_dropped	+= local.rx_dropped;
1094		stats->tx_dropped	+= local.tx_dropped;
1095		stats->rx_noroute	+= local.rx_noroute;
1096	}
1097}
1098
1099static int mpls_fill_stats_af(struct sk_buff *skb,
1100			      const struct net_device *dev)
1101{
1102	struct mpls_link_stats *stats;
1103	struct mpls_dev *mdev;
1104	struct nlattr *nla;
1105
1106	mdev = mpls_dev_get(dev);
1107	if (!mdev)
1108		return -ENODATA;
1109
1110	nla = nla_reserve_64bit(skb, MPLS_STATS_LINK,
1111				sizeof(struct mpls_link_stats),
1112				MPLS_STATS_UNSPEC);
1113	if (!nla)
1114		return -EMSGSIZE;
1115
1116	stats = nla_data(nla);
1117	mpls_get_stats(mdev, stats);
1118
1119	return 0;
1120}
1121
1122static size_t mpls_get_stats_af_size(const struct net_device *dev)
1123{
1124	struct mpls_dev *mdev;
1125
1126	mdev = mpls_dev_get(dev);
1127	if (!mdev)
1128		return 0;
1129
1130	return nla_total_size_64bit(sizeof(struct mpls_link_stats));
1131}
1132
1133static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev,
1134				     u32 portid, u32 seq, int event,
1135				     unsigned int flags, int type)
1136{
1137	struct nlmsghdr  *nlh;
1138	struct netconfmsg *ncm;
1139	bool all = false;
1140
1141	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
1142			flags);
1143	if (!nlh)
1144		return -EMSGSIZE;
1145
1146	if (type == NETCONFA_ALL)
1147		all = true;
1148
1149	ncm = nlmsg_data(nlh);
1150	ncm->ncm_family = AF_MPLS;
1151
1152	if (nla_put_s32(skb, NETCONFA_IFINDEX, mdev->dev->ifindex) < 0)
1153		goto nla_put_failure;
1154
1155	if ((all || type == NETCONFA_INPUT) &&
1156	    nla_put_s32(skb, NETCONFA_INPUT,
1157			mdev->input_enabled) < 0)
1158		goto nla_put_failure;
1159
1160	nlmsg_end(skb, nlh);
1161	return 0;
1162
1163nla_put_failure:
1164	nlmsg_cancel(skb, nlh);
1165	return -EMSGSIZE;
1166}
1167
1168static int mpls_netconf_msgsize_devconf(int type)
1169{
1170	int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1171			+ nla_total_size(4); /* NETCONFA_IFINDEX */
1172	bool all = false;
1173
1174	if (type == NETCONFA_ALL)
1175		all = true;
1176
1177	if (all || type == NETCONFA_INPUT)
1178		size += nla_total_size(4);
1179
1180	return size;
1181}
1182
1183static void mpls_netconf_notify_devconf(struct net *net, int event,
1184					int type, struct mpls_dev *mdev)
1185{
1186	struct sk_buff *skb;
1187	int err = -ENOBUFS;
1188
1189	skb = nlmsg_new(mpls_netconf_msgsize_devconf(type), GFP_KERNEL);
1190	if (!skb)
1191		goto errout;
1192
1193	err = mpls_netconf_fill_devconf(skb, mdev, 0, 0, event, 0, type);
1194	if (err < 0) {
1195		/* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
1196		WARN_ON(err == -EMSGSIZE);
1197		kfree_skb(skb);
1198		goto errout;
1199	}
1200
1201	rtnl_notify(skb, net, 0, RTNLGRP_MPLS_NETCONF, NULL, GFP_KERNEL);
1202	return;
1203errout:
1204	if (err < 0)
1205		rtnl_set_sk_err(net, RTNLGRP_MPLS_NETCONF, err);
1206}
1207
1208static const struct nla_policy devconf_mpls_policy[NETCONFA_MAX + 1] = {
1209	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
1210};
1211
1212static int mpls_netconf_valid_get_req(struct sk_buff *skb,
1213				      const struct nlmsghdr *nlh,
1214				      struct nlattr **tb,
1215				      struct netlink_ext_ack *extack)
1216{
1217	int i, err;
1218
1219	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
1220		NL_SET_ERR_MSG_MOD(extack,
1221				   "Invalid header for netconf get request");
1222		return -EINVAL;
1223	}
1224
1225	if (!netlink_strict_get_check(skb))
1226		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
1227					      tb, NETCONFA_MAX,
1228					      devconf_mpls_policy, extack);
1229
1230	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
1231					    tb, NETCONFA_MAX,
1232					    devconf_mpls_policy, extack);
1233	if (err)
1234		return err;
1235
1236	for (i = 0; i <= NETCONFA_MAX; i++) {
1237		if (!tb[i])
1238			continue;
1239
1240		switch (i) {
1241		case NETCONFA_IFINDEX:
1242			break;
1243		default:
1244			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
1245			return -EINVAL;
1246		}
1247	}
1248
1249	return 0;
1250}
1251
1252static int mpls_netconf_get_devconf(struct sk_buff *in_skb,
1253				    struct nlmsghdr *nlh,
1254				    struct netlink_ext_ack *extack)
1255{
1256	struct net *net = sock_net(in_skb->sk);
1257	struct nlattr *tb[NETCONFA_MAX + 1];
1258	struct net_device *dev;
1259	struct mpls_dev *mdev;
1260	struct sk_buff *skb;
1261	int ifindex;
1262	int err;
1263
1264	err = mpls_netconf_valid_get_req(in_skb, nlh, tb, extack);
1265	if (err < 0)
1266		goto errout;
1267
1268	err = -EINVAL;
1269	if (!tb[NETCONFA_IFINDEX])
1270		goto errout;
1271
1272	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
1273	dev = __dev_get_by_index(net, ifindex);
1274	if (!dev)
1275		goto errout;
1276
1277	mdev = mpls_dev_get(dev);
1278	if (!mdev)
1279		goto errout;
1280
1281	err = -ENOBUFS;
1282	skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
1283	if (!skb)
1284		goto errout;
1285
1286	err = mpls_netconf_fill_devconf(skb, mdev,
1287					NETLINK_CB(in_skb).portid,
1288					nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
1289					NETCONFA_ALL);
1290	if (err < 0) {
1291		/* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
1292		WARN_ON(err == -EMSGSIZE);
1293		kfree_skb(skb);
1294		goto errout;
1295	}
1296	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1297errout:
1298	return err;
1299}
1300
1301static int mpls_netconf_dump_devconf(struct sk_buff *skb,
1302				     struct netlink_callback *cb)
1303{
1304	const struct nlmsghdr *nlh = cb->nlh;
1305	struct net *net = sock_net(skb->sk);
1306	struct hlist_head *head;
1307	struct net_device *dev;
1308	struct mpls_dev *mdev;
1309	int idx, s_idx;
1310	int h, s_h;
1311
1312	if (cb->strict_check) {
1313		struct netlink_ext_ack *extack = cb->extack;
1314		struct netconfmsg *ncm;
1315
1316		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
1317			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
1318			return -EINVAL;
1319		}
1320
1321		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
1322			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
1323			return -EINVAL;
1324		}
1325	}
1326
1327	s_h = cb->args[0];
1328	s_idx = idx = cb->args[1];
1329
1330	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1331		idx = 0;
1332		head = &net->dev_index_head[h];
1333		rcu_read_lock();
1334		cb->seq = net->dev_base_seq;
1335		hlist_for_each_entry_rcu(dev, head, index_hlist) {
1336			if (idx < s_idx)
1337				goto cont;
1338			mdev = mpls_dev_get(dev);
1339			if (!mdev)
1340				goto cont;
1341			if (mpls_netconf_fill_devconf(skb, mdev,
1342						      NETLINK_CB(cb->skb).portid,
1343						      nlh->nlmsg_seq,
1344						      RTM_NEWNETCONF,
1345						      NLM_F_MULTI,
1346						      NETCONFA_ALL) < 0) {
1347				rcu_read_unlock();
1348				goto done;
1349			}
1350			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1351cont:
1352			idx++;
1353		}
1354		rcu_read_unlock();
1355	}
1356done:
1357	cb->args[0] = h;
1358	cb->args[1] = idx;
1359
1360	return skb->len;
1361}
1362
1363#define MPLS_PERDEV_SYSCTL_OFFSET(field)	\
1364	(&((struct mpls_dev *)0)->field)
1365
1366static int mpls_conf_proc(struct ctl_table *ctl, int write,
1367			  void *buffer, size_t *lenp, loff_t *ppos)
1368{
1369	int oval = *(int *)ctl->data;
1370	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1371
1372	if (write) {
1373		struct mpls_dev *mdev = ctl->extra1;
1374		int i = (int *)ctl->data - (int *)mdev;
1375		struct net *net = ctl->extra2;
1376		int val = *(int *)ctl->data;
1377
1378		if (i == offsetof(struct mpls_dev, input_enabled) &&
1379		    val != oval) {
1380			mpls_netconf_notify_devconf(net, RTM_NEWNETCONF,
1381						    NETCONFA_INPUT, mdev);
1382		}
1383	}
1384
1385	return ret;
1386}
1387
1388static const struct ctl_table mpls_dev_table[] = {
1389	{
1390		.procname	= "input",
1391		.maxlen		= sizeof(int),
1392		.mode		= 0644,
1393		.proc_handler	= mpls_conf_proc,
1394		.data		= MPLS_PERDEV_SYSCTL_OFFSET(input_enabled),
1395	},
1396	{ }
1397};
1398
1399static int mpls_dev_sysctl_register(struct net_device *dev,
1400				    struct mpls_dev *mdev)
1401{
1402	char path[sizeof("net/mpls/conf/") + IFNAMSIZ];
1403	struct net *net = dev_net(dev);
1404	struct ctl_table *table;
1405	int i;
1406
1407	table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL);
1408	if (!table)
1409		goto out;
1410
1411	/* Table data contains only offsets relative to the base of
1412	 * the mdev at this point, so make them absolute.
1413	 */
1414	for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) {
1415		table[i].data = (char *)mdev + (uintptr_t)table[i].data;
1416		table[i].extra1 = mdev;
1417		table[i].extra2 = net;
1418	}
1419
1420	snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name);
1421
1422	mdev->sysctl = register_net_sysctl_sz(net, path, table,
1423					      ARRAY_SIZE(mpls_dev_table));
1424	if (!mdev->sysctl)
1425		goto free;
1426
1427	mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, mdev);
1428	return 0;
1429
1430free:
1431	kfree(table);
1432out:
1433	mdev->sysctl = NULL;
1434	return -ENOBUFS;
1435}
1436
1437static void mpls_dev_sysctl_unregister(struct net_device *dev,
1438				       struct mpls_dev *mdev)
1439{
1440	struct net *net = dev_net(dev);
1441	struct ctl_table *table;
1442
1443	if (!mdev->sysctl)
1444		return;
1445
1446	table = mdev->sysctl->ctl_table_arg;
1447	unregister_net_sysctl_table(mdev->sysctl);
1448	kfree(table);
1449
1450	mpls_netconf_notify_devconf(net, RTM_DELNETCONF, 0, mdev);
1451}
1452
1453static struct mpls_dev *mpls_add_dev(struct net_device *dev)
1454{
1455	struct mpls_dev *mdev;
1456	int err = -ENOMEM;
1457	int i;
1458
1459	ASSERT_RTNL();
1460
1461	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
1462	if (!mdev)
1463		return ERR_PTR(err);
1464
1465	mdev->stats = alloc_percpu(struct mpls_pcpu_stats);
1466	if (!mdev->stats)
1467		goto free;
1468
1469	for_each_possible_cpu(i) {
1470		struct mpls_pcpu_stats *mpls_stats;
1471
1472		mpls_stats = per_cpu_ptr(mdev->stats, i);
1473		u64_stats_init(&mpls_stats->syncp);
1474	}
1475
1476	mdev->dev = dev;
1477
1478	err = mpls_dev_sysctl_register(dev, mdev);
1479	if (err)
1480		goto free;
1481
1482	rcu_assign_pointer(dev->mpls_ptr, mdev);
1483
1484	return mdev;
1485
1486free:
1487	free_percpu(mdev->stats);
1488	kfree(mdev);
1489	return ERR_PTR(err);
1490}
1491
1492static void mpls_dev_destroy_rcu(struct rcu_head *head)
1493{
1494	struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu);
1495
1496	free_percpu(mdev->stats);
1497	kfree(mdev);
1498}
1499
1500static int mpls_ifdown(struct net_device *dev, int event)
1501{
1502	struct mpls_route __rcu **platform_label;
1503	struct net *net = dev_net(dev);
1504	unsigned index;
1505
1506	platform_label = rtnl_dereference(net->mpls.platform_label);
1507	for (index = 0; index < net->mpls.platform_labels; index++) {
1508		struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1509		bool nh_del = false;
1510		u8 alive = 0;
1511
1512		if (!rt)
1513			continue;
1514
1515		if (event == NETDEV_UNREGISTER) {
1516			u8 deleted = 0;
1517
1518			for_nexthops(rt) {
1519				if (!nh->nh_dev || nh->nh_dev == dev)
1520					deleted++;
1521				if (nh->nh_dev == dev)
1522					nh_del = true;
1523			} endfor_nexthops(rt);
1524
1525			/* if there are no more nexthops, delete the route */
1526			if (deleted == rt->rt_nhn) {
1527				mpls_route_update(net, index, NULL, NULL);
1528				continue;
1529			}
1530
1531			if (nh_del) {
1532				size_t size = sizeof(*rt) + rt->rt_nhn *
1533					rt->rt_nh_size;
1534				struct mpls_route *orig = rt;
1535
1536				rt = kmemdup(orig, size, GFP_KERNEL);
1537				if (!rt)
1538					return -ENOMEM;
1539			}
1540		}
1541
1542		change_nexthops(rt) {
1543			unsigned int nh_flags = nh->nh_flags;
1544
1545			if (nh->nh_dev != dev)
1546				goto next;
1547
1548			switch (event) {
1549			case NETDEV_DOWN:
1550			case NETDEV_UNREGISTER:
1551				nh_flags |= RTNH_F_DEAD;
1552				fallthrough;
1553			case NETDEV_CHANGE:
1554				nh_flags |= RTNH_F_LINKDOWN;
 
 
1555				break;
1556			}
1557			if (event == NETDEV_UNREGISTER)
1558				nh->nh_dev = NULL;
1559
1560			if (nh->nh_flags != nh_flags)
1561				WRITE_ONCE(nh->nh_flags, nh_flags);
1562next:
1563			if (!(nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)))
1564				alive++;
1565		} endfor_nexthops(rt);
1566
1567		WRITE_ONCE(rt->rt_nhn_alive, alive);
1568
1569		if (nh_del)
1570			mpls_route_update(net, index, rt, NULL);
1571	}
1572
1573	return 0;
1574}
1575
1576static void mpls_ifup(struct net_device *dev, unsigned int flags)
1577{
1578	struct mpls_route __rcu **platform_label;
1579	struct net *net = dev_net(dev);
1580	unsigned index;
1581	u8 alive;
1582
1583	platform_label = rtnl_dereference(net->mpls.platform_label);
1584	for (index = 0; index < net->mpls.platform_labels; index++) {
1585		struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1586
1587		if (!rt)
1588			continue;
1589
1590		alive = 0;
1591		change_nexthops(rt) {
1592			unsigned int nh_flags = nh->nh_flags;
 
1593
1594			if (!(nh_flags & flags)) {
1595				alive++;
1596				continue;
1597			}
1598			if (nh->nh_dev != dev)
1599				continue;
1600			alive++;
1601			nh_flags &= ~flags;
1602			WRITE_ONCE(nh->nh_flags, nh_flags);
1603		} endfor_nexthops(rt);
1604
1605		WRITE_ONCE(rt->rt_nhn_alive, alive);
1606	}
1607}
1608
1609static int mpls_dev_notify(struct notifier_block *this, unsigned long event,
1610			   void *ptr)
1611{
1612	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1613	struct mpls_dev *mdev;
1614	unsigned int flags;
1615	int err;
1616
1617	if (event == NETDEV_REGISTER) {
1618		mdev = mpls_add_dev(dev);
1619		if (IS_ERR(mdev))
1620			return notifier_from_errno(PTR_ERR(mdev));
1621
 
 
 
 
 
 
1622		return NOTIFY_OK;
1623	}
1624
1625	mdev = mpls_dev_get(dev);
1626	if (!mdev)
1627		return NOTIFY_OK;
1628
1629	switch (event) {
1630
1631	case NETDEV_DOWN:
1632		err = mpls_ifdown(dev, event);
1633		if (err)
1634			return notifier_from_errno(err);
1635		break;
1636	case NETDEV_UP:
1637		flags = dev_get_flags(dev);
1638		if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1639			mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN);
1640		else
1641			mpls_ifup(dev, RTNH_F_DEAD);
1642		break;
1643	case NETDEV_CHANGE:
1644		flags = dev_get_flags(dev);
1645		if (flags & (IFF_RUNNING | IFF_LOWER_UP)) {
1646			mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN);
1647		} else {
1648			err = mpls_ifdown(dev, event);
1649			if (err)
1650				return notifier_from_errno(err);
1651		}
1652		break;
1653	case NETDEV_UNREGISTER:
1654		err = mpls_ifdown(dev, event);
1655		if (err)
1656			return notifier_from_errno(err);
1657		mdev = mpls_dev_get(dev);
1658		if (mdev) {
1659			mpls_dev_sysctl_unregister(dev, mdev);
1660			RCU_INIT_POINTER(dev->mpls_ptr, NULL);
1661			call_rcu(&mdev->rcu, mpls_dev_destroy_rcu);
1662		}
1663		break;
1664	case NETDEV_CHANGENAME:
1665		mdev = mpls_dev_get(dev);
1666		if (mdev) {
1667			mpls_dev_sysctl_unregister(dev, mdev);
 
 
1668			err = mpls_dev_sysctl_register(dev, mdev);
1669			if (err)
1670				return notifier_from_errno(err);
1671		}
1672		break;
1673	}
1674	return NOTIFY_OK;
1675}
1676
1677static struct notifier_block mpls_dev_notifier = {
1678	.notifier_call = mpls_dev_notify,
1679};
1680
1681static int nla_put_via(struct sk_buff *skb,
1682		       u8 table, const void *addr, int alen)
1683{
1684	static const int table_to_family[NEIGH_NR_TABLES + 1] = {
1685		AF_INET, AF_INET6, AF_DECnet, AF_PACKET,
1686	};
1687	struct nlattr *nla;
1688	struct rtvia *via;
1689	int family = AF_UNSPEC;
1690
1691	nla = nla_reserve(skb, RTA_VIA, alen + 2);
1692	if (!nla)
1693		return -EMSGSIZE;
1694
1695	if (table <= NEIGH_NR_TABLES)
1696		family = table_to_family[table];
1697
1698	via = nla_data(nla);
1699	via->rtvia_family = family;
1700	memcpy(via->rtvia_addr, addr, alen);
1701	return 0;
1702}
1703
1704int nla_put_labels(struct sk_buff *skb, int attrtype,
1705		   u8 labels, const u32 label[])
1706{
1707	struct nlattr *nla;
1708	struct mpls_shim_hdr *nla_label;
1709	bool bos;
1710	int i;
1711	nla = nla_reserve(skb, attrtype, labels*4);
1712	if (!nla)
1713		return -EMSGSIZE;
1714
1715	nla_label = nla_data(nla);
1716	bos = true;
1717	for (i = labels - 1; i >= 0; i--) {
1718		nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos);
1719		bos = false;
1720	}
1721
1722	return 0;
1723}
1724EXPORT_SYMBOL_GPL(nla_put_labels);
1725
1726int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels,
1727		   u32 label[], struct netlink_ext_ack *extack)
1728{
1729	unsigned len = nla_len(nla);
 
1730	struct mpls_shim_hdr *nla_label;
1731	u8 nla_labels;
1732	bool bos;
1733	int i;
1734
1735	/* len needs to be an even multiple of 4 (the label size). Number
1736	 * of labels is a u8 so check for overflow.
1737	 */
1738	if (len & 3 || len / 4 > 255) {
1739		NL_SET_ERR_MSG_ATTR(extack, nla,
1740				    "Invalid length for labels attribute");
1741		return -EINVAL;
1742	}
1743
1744	/* Limit the number of new labels allowed */
1745	nla_labels = len/4;
1746	if (nla_labels > max_labels) {
1747		NL_SET_ERR_MSG(extack, "Too many labels");
1748		return -EINVAL;
1749	}
1750
1751	/* when label == NULL, caller wants number of labels */
1752	if (!label)
1753		goto out;
1754
1755	nla_label = nla_data(nla);
1756	bos = true;
1757	for (i = nla_labels - 1; i >= 0; i--, bos = false) {
1758		struct mpls_entry_decoded dec;
1759		dec = mpls_entry_decode(nla_label + i);
1760
1761		/* Ensure the bottom of stack flag is properly set
1762		 * and ttl and tc are both clear.
1763		 */
1764		if (dec.ttl) {
1765			NL_SET_ERR_MSG_ATTR(extack, nla,
1766					    "TTL in label must be 0");
1767			return -EINVAL;
1768		}
1769
1770		if (dec.tc) {
1771			NL_SET_ERR_MSG_ATTR(extack, nla,
1772					    "Traffic class in label must be 0");
1773			return -EINVAL;
1774		}
1775
1776		if (dec.bos != bos) {
1777			NL_SET_BAD_ATTR(extack, nla);
1778			if (bos) {
1779				NL_SET_ERR_MSG(extack,
1780					       "BOS bit must be set in first label");
1781			} else {
1782				NL_SET_ERR_MSG(extack,
1783					       "BOS bit can only be set in first label");
1784			}
1785			return -EINVAL;
1786		}
1787
1788		switch (dec.label) {
1789		case MPLS_LABEL_IMPLNULL:
1790			/* RFC3032: This is a label that an LSR may
1791			 * assign and distribute, but which never
1792			 * actually appears in the encapsulation.
1793			 */
1794			NL_SET_ERR_MSG_ATTR(extack, nla,
1795					    "Implicit NULL Label (3) can not be used in encapsulation");
1796			return -EINVAL;
1797		}
1798
1799		label[i] = dec.label;
1800	}
1801out:
1802	*labels = nla_labels;
1803	return 0;
1804}
1805EXPORT_SYMBOL_GPL(nla_get_labels);
1806
1807static int rtm_to_route_config(struct sk_buff *skb,
1808			       struct nlmsghdr *nlh,
1809			       struct mpls_route_config *cfg,
1810			       struct netlink_ext_ack *extack)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1811{
1812	struct rtmsg *rtm;
1813	struct nlattr *tb[RTA_MAX+1];
1814	int index;
1815	int err;
1816
1817	err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
1818				     rtm_mpls_policy, extack);
1819	if (err < 0)
1820		goto errout;
1821
1822	err = -EINVAL;
1823	rtm = nlmsg_data(nlh);
 
1824
1825	if (rtm->rtm_family != AF_MPLS) {
1826		NL_SET_ERR_MSG(extack, "Invalid address family in rtmsg");
1827		goto errout;
1828	}
1829	if (rtm->rtm_dst_len != 20) {
1830		NL_SET_ERR_MSG(extack, "rtm_dst_len must be 20 for MPLS");
1831		goto errout;
1832	}
1833	if (rtm->rtm_src_len != 0) {
1834		NL_SET_ERR_MSG(extack, "rtm_src_len must be 0 for MPLS");
1835		goto errout;
1836	}
1837	if (rtm->rtm_tos != 0) {
1838		NL_SET_ERR_MSG(extack, "rtm_tos must be 0 for MPLS");
1839		goto errout;
1840	}
1841	if (rtm->rtm_table != RT_TABLE_MAIN) {
1842		NL_SET_ERR_MSG(extack,
1843			       "MPLS only supports the main route table");
1844		goto errout;
1845	}
1846	/* Any value is acceptable for rtm_protocol */
1847
1848	/* As mpls uses destination specific addresses
1849	 * (or source specific address in the case of multicast)
1850	 * all addresses have universal scope.
1851	 */
1852	if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) {
1853		NL_SET_ERR_MSG(extack,
1854			       "Invalid route scope  - MPLS only supports UNIVERSE");
1855		goto errout;
1856	}
1857	if (rtm->rtm_type != RTN_UNICAST) {
1858		NL_SET_ERR_MSG(extack,
1859			       "Invalid route type - MPLS only supports UNICAST");
1860		goto errout;
1861	}
1862	if (rtm->rtm_flags != 0) {
1863		NL_SET_ERR_MSG(extack, "rtm_flags must be 0 for MPLS");
1864		goto errout;
1865	}
1866
1867	cfg->rc_label		= LABEL_NOT_SPECIFIED;
1868	cfg->rc_protocol	= rtm->rtm_protocol;
1869	cfg->rc_via_table	= MPLS_NEIGH_TABLE_UNSPEC;
1870	cfg->rc_ttl_propagate	= MPLS_TTL_PROP_DEFAULT;
1871	cfg->rc_nlflags		= nlh->nlmsg_flags;
1872	cfg->rc_nlinfo.portid	= NETLINK_CB(skb).portid;
1873	cfg->rc_nlinfo.nlh	= nlh;
1874	cfg->rc_nlinfo.nl_net	= sock_net(skb->sk);
1875
1876	for (index = 0; index <= RTA_MAX; index++) {
1877		struct nlattr *nla = tb[index];
1878		if (!nla)
1879			continue;
1880
1881		switch (index) {
1882		case RTA_OIF:
1883			cfg->rc_ifindex = nla_get_u32(nla);
1884			break;
1885		case RTA_NEWDST:
1886			if (nla_get_labels(nla, MAX_NEW_LABELS,
1887					   &cfg->rc_output_labels,
1888					   cfg->rc_output_label, extack))
1889				goto errout;
1890			break;
1891		case RTA_DST:
1892		{
1893			u8 label_count;
1894			if (nla_get_labels(nla, 1, &label_count,
1895					   &cfg->rc_label, extack))
1896				goto errout;
1897
1898			if (!mpls_label_ok(cfg->rc_nlinfo.nl_net,
1899					   &cfg->rc_label, extack))
1900				goto errout;
 
1901			break;
1902		}
1903		case RTA_GATEWAY:
1904			NL_SET_ERR_MSG(extack, "MPLS does not support RTA_GATEWAY attribute");
1905			goto errout;
1906		case RTA_VIA:
1907		{
1908			if (nla_get_via(nla, &cfg->rc_via_alen,
1909					&cfg->rc_via_table, cfg->rc_via,
1910					extack))
1911				goto errout;
1912			break;
1913		}
1914		case RTA_MULTIPATH:
1915		{
1916			cfg->rc_mp = nla_data(nla);
1917			cfg->rc_mp_len = nla_len(nla);
1918			break;
1919		}
1920		case RTA_TTL_PROPAGATE:
1921		{
1922			u8 ttl_propagate = nla_get_u8(nla);
1923
1924			if (ttl_propagate > 1) {
1925				NL_SET_ERR_MSG_ATTR(extack, nla,
1926						    "RTA_TTL_PROPAGATE can only be 0 or 1");
1927				goto errout;
1928			}
1929			cfg->rc_ttl_propagate = ttl_propagate ?
1930				MPLS_TTL_PROP_ENABLED :
1931				MPLS_TTL_PROP_DISABLED;
1932			break;
1933		}
1934		default:
1935			NL_SET_ERR_MSG_ATTR(extack, nla, "Unknown attribute");
1936			/* Unsupported attribute */
1937			goto errout;
1938		}
1939	}
1940
1941	err = 0;
1942errout:
1943	return err;
1944}
1945
1946static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
1947			     struct netlink_ext_ack *extack)
1948{
1949	struct mpls_route_config *cfg;
1950	int err;
1951
1952	cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
1953	if (!cfg)
1954		return -ENOMEM;
1955
1956	err = rtm_to_route_config(skb, nlh, cfg, extack);
1957	if (err < 0)
1958		goto out;
1959
1960	err = mpls_route_del(cfg, extack);
1961out:
1962	kfree(cfg);
1963
1964	return err;
1965}
1966
1967
1968static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
1969			     struct netlink_ext_ack *extack)
1970{
1971	struct mpls_route_config *cfg;
1972	int err;
1973
1974	cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
1975	if (!cfg)
1976		return -ENOMEM;
1977
1978	err = rtm_to_route_config(skb, nlh, cfg, extack);
1979	if (err < 0)
1980		goto out;
1981
1982	err = mpls_route_add(cfg, extack);
1983out:
1984	kfree(cfg);
1985
1986	return err;
1987}
1988
1989static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event,
1990			   u32 label, struct mpls_route *rt, int flags)
1991{
1992	struct net_device *dev;
1993	struct nlmsghdr *nlh;
1994	struct rtmsg *rtm;
1995
1996	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
1997	if (nlh == NULL)
1998		return -EMSGSIZE;
1999
2000	rtm = nlmsg_data(nlh);
2001	rtm->rtm_family = AF_MPLS;
2002	rtm->rtm_dst_len = 20;
2003	rtm->rtm_src_len = 0;
2004	rtm->rtm_tos = 0;
2005	rtm->rtm_table = RT_TABLE_MAIN;
2006	rtm->rtm_protocol = rt->rt_protocol;
2007	rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2008	rtm->rtm_type = RTN_UNICAST;
2009	rtm->rtm_flags = 0;
2010
2011	if (nla_put_labels(skb, RTA_DST, 1, &label))
2012		goto nla_put_failure;
2013
2014	if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) {
2015		bool ttl_propagate =
2016			rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED;
2017
2018		if (nla_put_u8(skb, RTA_TTL_PROPAGATE,
2019			       ttl_propagate))
2020			goto nla_put_failure;
2021	}
2022	if (rt->rt_nhn == 1) {
2023		const struct mpls_nh *nh = rt->rt_nh;
2024
2025		if (nh->nh_labels &&
2026		    nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
2027				   nh->nh_label))
2028			goto nla_put_failure;
2029		if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2030		    nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
2031				nh->nh_via_alen))
2032			goto nla_put_failure;
2033		dev = nh->nh_dev;
2034		if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
2035			goto nla_put_failure;
2036		if (nh->nh_flags & RTNH_F_LINKDOWN)
2037			rtm->rtm_flags |= RTNH_F_LINKDOWN;
2038		if (nh->nh_flags & RTNH_F_DEAD)
2039			rtm->rtm_flags |= RTNH_F_DEAD;
2040	} else {
2041		struct rtnexthop *rtnh;
2042		struct nlattr *mp;
2043		u8 linkdown = 0;
2044		u8 dead = 0;
2045
2046		mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
2047		if (!mp)
2048			goto nla_put_failure;
2049
2050		for_nexthops(rt) {
2051			dev = nh->nh_dev;
2052			if (!dev)
2053				continue;
2054
2055			rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh));
2056			if (!rtnh)
2057				goto nla_put_failure;
2058
2059			rtnh->rtnh_ifindex = dev->ifindex;
 
 
2060			if (nh->nh_flags & RTNH_F_LINKDOWN) {
2061				rtnh->rtnh_flags |= RTNH_F_LINKDOWN;
2062				linkdown++;
2063			}
2064			if (nh->nh_flags & RTNH_F_DEAD) {
2065				rtnh->rtnh_flags |= RTNH_F_DEAD;
2066				dead++;
2067			}
2068
2069			if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST,
2070							    nh->nh_labels,
2071							    nh->nh_label))
2072				goto nla_put_failure;
2073			if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2074			    nla_put_via(skb, nh->nh_via_table,
2075					mpls_nh_via(rt, nh),
2076					nh->nh_via_alen))
2077				goto nla_put_failure;
2078
2079			/* length of rtnetlink header + attributes */
2080			rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh;
2081		} endfor_nexthops(rt);
2082
2083		if (linkdown == rt->rt_nhn)
2084			rtm->rtm_flags |= RTNH_F_LINKDOWN;
2085		if (dead == rt->rt_nhn)
2086			rtm->rtm_flags |= RTNH_F_DEAD;
2087
2088		nla_nest_end(skb, mp);
2089	}
2090
2091	nlmsg_end(skb, nlh);
2092	return 0;
2093
2094nla_put_failure:
2095	nlmsg_cancel(skb, nlh);
2096	return -EMSGSIZE;
2097}
2098
2099#if IS_ENABLED(CONFIG_INET)
2100static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
2101				   struct fib_dump_filter *filter,
2102				   struct netlink_callback *cb)
2103{
2104	return ip_valid_fib_dump_req(net, nlh, filter, cb);
2105}
2106#else
2107static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
2108				   struct fib_dump_filter *filter,
2109				   struct netlink_callback *cb)
2110{
2111	struct netlink_ext_ack *extack = cb->extack;
2112	struct nlattr *tb[RTA_MAX + 1];
2113	struct rtmsg *rtm;
2114	int err, i;
2115
2116	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2117		NL_SET_ERR_MSG_MOD(extack, "Invalid header for FIB dump request");
2118		return -EINVAL;
2119	}
2120
2121	rtm = nlmsg_data(nlh);
2122	if (rtm->rtm_dst_len || rtm->rtm_src_len  || rtm->rtm_tos   ||
2123	    rtm->rtm_table   || rtm->rtm_scope    || rtm->rtm_type  ||
2124	    rtm->rtm_flags) {
2125		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for FIB dump request");
2126		return -EINVAL;
2127	}
2128
2129	if (rtm->rtm_protocol) {
2130		filter->protocol = rtm->rtm_protocol;
2131		filter->filter_set = 1;
2132		cb->answer_flags = NLM_F_DUMP_FILTERED;
2133	}
2134
2135	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2136					    rtm_mpls_policy, extack);
2137	if (err < 0)
2138		return err;
2139
2140	for (i = 0; i <= RTA_MAX; ++i) {
2141		int ifindex;
2142
2143		if (i == RTA_OIF) {
2144			ifindex = nla_get_u32(tb[i]);
2145			filter->dev = __dev_get_by_index(net, ifindex);
2146			if (!filter->dev)
2147				return -ENODEV;
2148			filter->filter_set = 1;
2149		} else if (tb[i]) {
2150			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
2151			return -EINVAL;
2152		}
2153	}
2154
2155	return 0;
2156}
2157#endif
2158
2159static bool mpls_rt_uses_dev(struct mpls_route *rt,
2160			     const struct net_device *dev)
2161{
2162	if (rt->rt_nhn == 1) {
2163		struct mpls_nh *nh = rt->rt_nh;
2164
2165		if (nh->nh_dev == dev)
2166			return true;
2167	} else {
2168		for_nexthops(rt) {
2169			if (nh->nh_dev == dev)
2170				return true;
2171		} endfor_nexthops(rt);
2172	}
2173
2174	return false;
2175}
2176
2177static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
2178{
2179	const struct nlmsghdr *nlh = cb->nlh;
2180	struct net *net = sock_net(skb->sk);
2181	struct mpls_route __rcu **platform_label;
2182	struct fib_dump_filter filter = {};
2183	unsigned int flags = NLM_F_MULTI;
2184	size_t platform_labels;
2185	unsigned int index;
2186
2187	ASSERT_RTNL();
2188
2189	if (cb->strict_check) {
2190		int err;
2191
2192		err = mpls_valid_fib_dump_req(net, nlh, &filter, cb);
2193		if (err < 0)
2194			return err;
2195
2196		/* for MPLS, there is only 1 table with fixed type and flags.
2197		 * If either are set in the filter then return nothing.
2198		 */
2199		if ((filter.table_id && filter.table_id != RT_TABLE_MAIN) ||
2200		    (filter.rt_type && filter.rt_type != RTN_UNICAST) ||
2201		     filter.flags)
2202			return skb->len;
2203	}
2204
2205	index = cb->args[0];
2206	if (index < MPLS_LABEL_FIRST_UNRESERVED)
2207		index = MPLS_LABEL_FIRST_UNRESERVED;
2208
2209	platform_label = rtnl_dereference(net->mpls.platform_label);
2210	platform_labels = net->mpls.platform_labels;
2211
2212	if (filter.filter_set)
2213		flags |= NLM_F_DUMP_FILTERED;
2214
2215	for (; index < platform_labels; index++) {
2216		struct mpls_route *rt;
2217
2218		rt = rtnl_dereference(platform_label[index]);
2219		if (!rt)
2220			continue;
2221
2222		if ((filter.dev && !mpls_rt_uses_dev(rt, filter.dev)) ||
2223		    (filter.protocol && rt->rt_protocol != filter.protocol))
2224			continue;
2225
2226		if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,
2227				    cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2228				    index, rt, flags) < 0)
2229			break;
2230	}
2231	cb->args[0] = index;
2232
2233	return skb->len;
2234}
2235
2236static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
2237{
2238	size_t payload =
2239		NLMSG_ALIGN(sizeof(struct rtmsg))
2240		+ nla_total_size(4)			/* RTA_DST */
2241		+ nla_total_size(1);			/* RTA_TTL_PROPAGATE */
2242
2243	if (rt->rt_nhn == 1) {
2244		struct mpls_nh *nh = rt->rt_nh;
2245
2246		if (nh->nh_dev)
2247			payload += nla_total_size(4); /* RTA_OIF */
2248		if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */
2249			payload += nla_total_size(2 + nh->nh_via_alen);
2250		if (nh->nh_labels) /* RTA_NEWDST */
2251			payload += nla_total_size(nh->nh_labels * 4);
2252	} else {
2253		/* each nexthop is packed in an attribute */
2254		size_t nhsize = 0;
2255
2256		for_nexthops(rt) {
2257			if (!nh->nh_dev)
2258				continue;
2259			nhsize += nla_total_size(sizeof(struct rtnexthop));
2260			/* RTA_VIA */
2261			if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC)
2262				nhsize += nla_total_size(2 + nh->nh_via_alen);
2263			if (nh->nh_labels)
2264				nhsize += nla_total_size(nh->nh_labels * 4);
2265		} endfor_nexthops(rt);
2266		/* nested attribute */
2267		payload += nla_total_size(nhsize);
2268	}
2269
2270	return payload;
2271}
2272
2273static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
2274		       struct nlmsghdr *nlh, struct net *net, u32 portid,
2275		       unsigned int nlm_flags)
2276{
2277	struct sk_buff *skb;
2278	u32 seq = nlh ? nlh->nlmsg_seq : 0;
2279	int err = -ENOBUFS;
2280
2281	skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
2282	if (skb == NULL)
2283		goto errout;
2284
2285	err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags);
2286	if (err < 0) {
2287		/* -EMSGSIZE implies BUG in lfib_nlmsg_size */
2288		WARN_ON(err == -EMSGSIZE);
2289		kfree_skb(skb);
2290		goto errout;
2291	}
2292	rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL);
2293
2294	return;
2295errout:
2296	if (err < 0)
2297		rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err);
2298}
2299
2300static int mpls_valid_getroute_req(struct sk_buff *skb,
2301				   const struct nlmsghdr *nlh,
2302				   struct nlattr **tb,
2303				   struct netlink_ext_ack *extack)
2304{
2305	struct rtmsg *rtm;
2306	int i, err;
2307
2308	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2309		NL_SET_ERR_MSG_MOD(extack,
2310				   "Invalid header for get route request");
2311		return -EINVAL;
2312	}
2313
2314	if (!netlink_strict_get_check(skb))
2315		return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
2316					      rtm_mpls_policy, extack);
2317
2318	rtm = nlmsg_data(nlh);
2319	if ((rtm->rtm_dst_len && rtm->rtm_dst_len != 20) ||
2320	    rtm->rtm_src_len || rtm->rtm_tos || rtm->rtm_table ||
2321	    rtm->rtm_protocol || rtm->rtm_scope || rtm->rtm_type) {
2322		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request");
2323		return -EINVAL;
2324	}
2325	if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) {
2326		NL_SET_ERR_MSG_MOD(extack,
2327				   "Invalid flags for get route request");
2328		return -EINVAL;
2329	}
2330
2331	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2332					    rtm_mpls_policy, extack);
2333	if (err)
2334		return err;
2335
2336	if ((tb[RTA_DST] || tb[RTA_NEWDST]) && !rtm->rtm_dst_len) {
2337		NL_SET_ERR_MSG_MOD(extack, "rtm_dst_len must be 20 for MPLS");
2338		return -EINVAL;
2339	}
2340
2341	for (i = 0; i <= RTA_MAX; i++) {
2342		if (!tb[i])
2343			continue;
2344
2345		switch (i) {
2346		case RTA_DST:
2347		case RTA_NEWDST:
2348			break;
2349		default:
2350			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
2351			return -EINVAL;
2352		}
2353	}
2354
2355	return 0;
2356}
2357
2358static int mpls_getroute(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
2359			 struct netlink_ext_ack *extack)
2360{
2361	struct net *net = sock_net(in_skb->sk);
2362	u32 portid = NETLINK_CB(in_skb).portid;
2363	u32 in_label = LABEL_NOT_SPECIFIED;
2364	struct nlattr *tb[RTA_MAX + 1];
2365	u32 labels[MAX_NEW_LABELS];
2366	struct mpls_shim_hdr *hdr;
2367	unsigned int hdr_size = 0;
2368	const struct mpls_nh *nh;
2369	struct net_device *dev;
2370	struct mpls_route *rt;
2371	struct rtmsg *rtm, *r;
2372	struct nlmsghdr *nlh;
2373	struct sk_buff *skb;
2374	u8 n_labels;
2375	int err;
2376
2377	err = mpls_valid_getroute_req(in_skb, in_nlh, tb, extack);
2378	if (err < 0)
2379		goto errout;
2380
2381	rtm = nlmsg_data(in_nlh);
2382
2383	if (tb[RTA_DST]) {
2384		u8 label_count;
2385
2386		if (nla_get_labels(tb[RTA_DST], 1, &label_count,
2387				   &in_label, extack)) {
2388			err = -EINVAL;
2389			goto errout;
2390		}
2391
2392		if (!mpls_label_ok(net, &in_label, extack)) {
2393			err = -EINVAL;
2394			goto errout;
2395		}
2396	}
2397
2398	rt = mpls_route_input_rcu(net, in_label);
2399	if (!rt) {
2400		err = -ENETUNREACH;
2401		goto errout;
2402	}
2403
2404	if (rtm->rtm_flags & RTM_F_FIB_MATCH) {
2405		skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
2406		if (!skb) {
2407			err = -ENOBUFS;
2408			goto errout;
2409		}
2410
2411		err = mpls_dump_route(skb, portid, in_nlh->nlmsg_seq,
2412				      RTM_NEWROUTE, in_label, rt, 0);
2413		if (err < 0) {
2414			/* -EMSGSIZE implies BUG in lfib_nlmsg_size */
2415			WARN_ON(err == -EMSGSIZE);
2416			goto errout_free;
2417		}
2418
2419		return rtnl_unicast(skb, net, portid);
2420	}
2421
2422	if (tb[RTA_NEWDST]) {
2423		if (nla_get_labels(tb[RTA_NEWDST], MAX_NEW_LABELS, &n_labels,
2424				   labels, extack) != 0) {
2425			err = -EINVAL;
2426			goto errout;
2427		}
2428
2429		hdr_size = n_labels * sizeof(struct mpls_shim_hdr);
2430	}
2431
2432	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2433	if (!skb) {
2434		err = -ENOBUFS;
2435		goto errout;
2436	}
2437
2438	skb->protocol = htons(ETH_P_MPLS_UC);
2439
2440	if (hdr_size) {
2441		bool bos;
2442		int i;
2443
2444		if (skb_cow(skb, hdr_size)) {
2445			err = -ENOBUFS;
2446			goto errout_free;
2447		}
2448
2449		skb_reserve(skb, hdr_size);
2450		skb_push(skb, hdr_size);
2451		skb_reset_network_header(skb);
2452
2453		/* Push new labels */
2454		hdr = mpls_hdr(skb);
2455		bos = true;
2456		for (i = n_labels - 1; i >= 0; i--) {
2457			hdr[i] = mpls_entry_encode(labels[i],
2458						   1, 0, bos);
2459			bos = false;
2460		}
2461	}
2462
2463	nh = mpls_select_multipath(rt, skb);
2464	if (!nh) {
2465		err = -ENETUNREACH;
2466		goto errout_free;
2467	}
2468
2469	if (hdr_size) {
2470		skb_pull(skb, hdr_size);
2471		skb_reset_network_header(skb);
2472	}
2473
2474	nlh = nlmsg_put(skb, portid, in_nlh->nlmsg_seq,
2475			RTM_NEWROUTE, sizeof(*r), 0);
2476	if (!nlh) {
2477		err = -EMSGSIZE;
2478		goto errout_free;
2479	}
2480
2481	r = nlmsg_data(nlh);
2482	r->rtm_family	 = AF_MPLS;
2483	r->rtm_dst_len	= 20;
2484	r->rtm_src_len	= 0;
2485	r->rtm_table	= RT_TABLE_MAIN;
2486	r->rtm_type	= RTN_UNICAST;
2487	r->rtm_scope	= RT_SCOPE_UNIVERSE;
2488	r->rtm_protocol = rt->rt_protocol;
2489	r->rtm_flags	= 0;
2490
2491	if (nla_put_labels(skb, RTA_DST, 1, &in_label))
2492		goto nla_put_failure;
2493
2494	if (nh->nh_labels &&
2495	    nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
2496			   nh->nh_label))
2497		goto nla_put_failure;
2498
2499	if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2500	    nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
2501			nh->nh_via_alen))
2502		goto nla_put_failure;
2503	dev = nh->nh_dev;
2504	if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
2505		goto nla_put_failure;
2506
2507	nlmsg_end(skb, nlh);
2508
2509	err = rtnl_unicast(skb, net, portid);
2510errout:
2511	return err;
2512
2513nla_put_failure:
2514	nlmsg_cancel(skb, nlh);
2515	err = -EMSGSIZE;
2516errout_free:
2517	kfree_skb(skb);
2518	return err;
2519}
2520
2521static int resize_platform_label_table(struct net *net, size_t limit)
2522{
2523	size_t size = sizeof(struct mpls_route *) * limit;
2524	size_t old_limit;
2525	size_t cp_size;
2526	struct mpls_route __rcu **labels = NULL, **old;
2527	struct mpls_route *rt0 = NULL, *rt2 = NULL;
2528	unsigned index;
2529
2530	if (size) {
2531		labels = kvzalloc(size, GFP_KERNEL);
 
 
 
2532		if (!labels)
2533			goto nolabels;
2534	}
2535
2536	/* In case the predefined labels need to be populated */
2537	if (limit > MPLS_LABEL_IPV4NULL) {
2538		struct net_device *lo = net->loopback_dev;
2539		rt0 = mpls_rt_alloc(1, lo->addr_len, 0);
2540		if (IS_ERR(rt0))
2541			goto nort0;
2542		rt0->rt_nh->nh_dev = lo;
2543		rt0->rt_protocol = RTPROT_KERNEL;
2544		rt0->rt_payload_type = MPT_IPV4;
2545		rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
2546		rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
2547		rt0->rt_nh->nh_via_alen = lo->addr_len;
2548		memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr,
2549		       lo->addr_len);
2550	}
2551	if (limit > MPLS_LABEL_IPV6NULL) {
2552		struct net_device *lo = net->loopback_dev;
2553		rt2 = mpls_rt_alloc(1, lo->addr_len, 0);
2554		if (IS_ERR(rt2))
2555			goto nort2;
2556		rt2->rt_nh->nh_dev = lo;
2557		rt2->rt_protocol = RTPROT_KERNEL;
2558		rt2->rt_payload_type = MPT_IPV6;
2559		rt2->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
2560		rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
2561		rt2->rt_nh->nh_via_alen = lo->addr_len;
2562		memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr,
2563		       lo->addr_len);
2564	}
2565
2566	rtnl_lock();
2567	/* Remember the original table */
2568	old = rtnl_dereference(net->mpls.platform_label);
2569	old_limit = net->mpls.platform_labels;
2570
2571	/* Free any labels beyond the new table */
2572	for (index = limit; index < old_limit; index++)
2573		mpls_route_update(net, index, NULL, NULL);
2574
2575	/* Copy over the old labels */
2576	cp_size = size;
2577	if (old_limit < limit)
2578		cp_size = old_limit * sizeof(struct mpls_route *);
2579
2580	memcpy(labels, old, cp_size);
2581
2582	/* If needed set the predefined labels */
2583	if ((old_limit <= MPLS_LABEL_IPV6NULL) &&
2584	    (limit > MPLS_LABEL_IPV6NULL)) {
2585		RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2);
2586		rt2 = NULL;
2587	}
2588
2589	if ((old_limit <= MPLS_LABEL_IPV4NULL) &&
2590	    (limit > MPLS_LABEL_IPV4NULL)) {
2591		RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0);
2592		rt0 = NULL;
2593	}
2594
2595	/* Update the global pointers */
2596	net->mpls.platform_labels = limit;
2597	rcu_assign_pointer(net->mpls.platform_label, labels);
2598
2599	rtnl_unlock();
2600
2601	mpls_rt_free(rt2);
2602	mpls_rt_free(rt0);
2603
2604	if (old) {
2605		synchronize_rcu();
2606		kvfree(old);
2607	}
2608	return 0;
2609
2610nort2:
2611	mpls_rt_free(rt0);
2612nort0:
2613	kvfree(labels);
2614nolabels:
2615	return -ENOMEM;
2616}
2617
2618static int mpls_platform_labels(struct ctl_table *table, int write,
2619				void *buffer, size_t *lenp, loff_t *ppos)
2620{
2621	struct net *net = table->data;
2622	int platform_labels = net->mpls.platform_labels;
2623	int ret;
2624	struct ctl_table tmp = {
2625		.procname	= table->procname,
2626		.data		= &platform_labels,
2627		.maxlen		= sizeof(int),
2628		.mode		= table->mode,
2629		.extra1		= SYSCTL_ZERO,
2630		.extra2		= &label_limit,
2631	};
2632
2633	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2634
2635	if (write && ret == 0)
2636		ret = resize_platform_label_table(net, platform_labels);
2637
2638	return ret;
2639}
2640
2641#define MPLS_NS_SYSCTL_OFFSET(field)		\
2642	(&((struct net *)0)->field)
2643
2644static const struct ctl_table mpls_table[] = {
2645	{
2646		.procname	= "platform_labels",
2647		.data		= NULL,
2648		.maxlen		= sizeof(int),
2649		.mode		= 0644,
2650		.proc_handler	= mpls_platform_labels,
2651	},
2652	{
2653		.procname	= "ip_ttl_propagate",
2654		.data		= MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate),
2655		.maxlen		= sizeof(int),
2656		.mode		= 0644,
2657		.proc_handler	= proc_dointvec_minmax,
2658		.extra1		= SYSCTL_ZERO,
2659		.extra2		= SYSCTL_ONE,
2660	},
2661	{
2662		.procname	= "default_ttl",
2663		.data		= MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl),
2664		.maxlen		= sizeof(int),
2665		.mode		= 0644,
2666		.proc_handler	= proc_dointvec_minmax,
2667		.extra1		= SYSCTL_ONE,
2668		.extra2		= &ttl_max,
2669	},
2670	{ }
2671};
2672
2673static int mpls_net_init(struct net *net)
2674{
2675	struct ctl_table *table;
2676	int i;
2677
2678	net->mpls.platform_labels = 0;
2679	net->mpls.platform_label = NULL;
2680	net->mpls.ip_ttl_propagate = 1;
2681	net->mpls.default_ttl = 255;
2682
2683	table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
2684	if (table == NULL)
2685		return -ENOMEM;
2686
2687	/* Table data contains only offsets relative to the base of
2688	 * the mdev at this point, so make them absolute.
2689	 */
2690	for (i = 0; i < ARRAY_SIZE(mpls_table) - 1; i++)
2691		table[i].data = (char *)net + (uintptr_t)table[i].data;
2692
2693	net->mpls.ctl = register_net_sysctl_sz(net, "net/mpls", table,
2694					       ARRAY_SIZE(mpls_table));
2695	if (net->mpls.ctl == NULL) {
2696		kfree(table);
2697		return -ENOMEM;
2698	}
2699
2700	return 0;
2701}
2702
2703static void mpls_net_exit(struct net *net)
2704{
2705	struct mpls_route __rcu **platform_label;
2706	size_t platform_labels;
2707	struct ctl_table *table;
2708	unsigned int index;
2709
2710	table = net->mpls.ctl->ctl_table_arg;
2711	unregister_net_sysctl_table(net->mpls.ctl);
2712	kfree(table);
2713
2714	/* An rcu grace period has passed since there was a device in
2715	 * the network namespace (and thus the last in flight packet)
2716	 * left this network namespace.  This is because
2717	 * unregister_netdevice_many and netdev_run_todo has completed
2718	 * for each network device that was in this network namespace.
2719	 *
2720	 * As such no additional rcu synchronization is necessary when
2721	 * freeing the platform_label table.
2722	 */
2723	rtnl_lock();
2724	platform_label = rtnl_dereference(net->mpls.platform_label);
2725	platform_labels = net->mpls.platform_labels;
2726	for (index = 0; index < platform_labels; index++) {
2727		struct mpls_route *rt = rtnl_dereference(platform_label[index]);
2728		RCU_INIT_POINTER(platform_label[index], NULL);
2729		mpls_notify_route(net, index, rt, NULL, NULL);
2730		mpls_rt_free(rt);
2731	}
2732	rtnl_unlock();
2733
2734	kvfree(platform_label);
2735}
2736
2737static struct pernet_operations mpls_net_ops = {
2738	.init = mpls_net_init,
2739	.exit = mpls_net_exit,
2740};
2741
2742static struct rtnl_af_ops mpls_af_ops __read_mostly = {
2743	.family		   = AF_MPLS,
2744	.fill_stats_af	   = mpls_fill_stats_af,
2745	.get_stats_af_size = mpls_get_stats_af_size,
2746};
2747
2748static int __init mpls_init(void)
2749{
2750	int err;
2751
2752	BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4);
2753
2754	err = register_pernet_subsys(&mpls_net_ops);
2755	if (err)
2756		goto out;
2757
2758	err = register_netdevice_notifier(&mpls_dev_notifier);
2759	if (err)
2760		goto out_unregister_pernet;
2761
2762	dev_add_pack(&mpls_packet_type);
2763
2764	rtnl_af_register(&mpls_af_ops);
2765
2766	rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_NEWROUTE,
2767			     mpls_rtm_newroute, NULL, 0);
2768	rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_DELROUTE,
2769			     mpls_rtm_delroute, NULL, 0);
2770	rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETROUTE,
2771			     mpls_getroute, mpls_dump_routes, 0);
2772	rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETNETCONF,
2773			     mpls_netconf_get_devconf,
2774			     mpls_netconf_dump_devconf, 0);
2775	err = ipgre_tunnel_encap_add_mpls_ops();
2776	if (err)
2777		pr_err("Can't add mpls over gre tunnel ops\n");
2778
2779	err = 0;
2780out:
2781	return err;
2782
2783out_unregister_pernet:
2784	unregister_pernet_subsys(&mpls_net_ops);
2785	goto out;
2786}
2787module_init(mpls_init);
2788
2789static void __exit mpls_exit(void)
2790{
2791	rtnl_unregister_all(PF_MPLS);
2792	rtnl_af_unregister(&mpls_af_ops);
2793	dev_remove_pack(&mpls_packet_type);
2794	unregister_netdevice_notifier(&mpls_dev_notifier);
2795	unregister_pernet_subsys(&mpls_net_ops);
2796	ipgre_tunnel_encap_del_mpls_ops();
2797}
2798module_exit(mpls_exit);
2799
2800MODULE_DESCRIPTION("MultiProtocol Label Switching");
2801MODULE_LICENSE("GPL v2");
2802MODULE_ALIAS_NETPROTO(PF_MPLS);