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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * vrf.c: device driver to encapsulate a VRF space
   4 *
   5 * Copyright (c) 2015 Cumulus Networks. All rights reserved.
   6 * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
   7 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
   8 *
   9 * Based on dummy, team and ipvlan drivers
 
 
 
 
 
  10 */
  11
  12#include <linux/ethtool.h>
  13#include <linux/module.h>
  14#include <linux/kernel.h>
  15#include <linux/netdevice.h>
  16#include <linux/etherdevice.h>
  17#include <linux/ip.h>
  18#include <linux/init.h>
  19#include <linux/moduleparam.h>
  20#include <linux/netfilter.h>
  21#include <linux/rtnetlink.h>
  22#include <net/rtnetlink.h>
  23#include <linux/u64_stats_sync.h>
  24#include <linux/hashtable.h>
  25#include <linux/spinlock_types.h>
  26
  27#include <linux/inetdevice.h>
  28#include <net/arp.h>
  29#include <net/ip.h>
  30#include <net/ip_fib.h>
  31#include <net/ip6_fib.h>
  32#include <net/ip6_route.h>
  33#include <net/route.h>
  34#include <net/addrconf.h>
  35#include <net/l3mdev.h>
  36#include <net/fib_rules.h>
  37#include <net/sch_generic.h>
  38#include <net/netns/generic.h>
  39#include <net/netfilter/nf_conntrack.h>
  40#include <net/inet_dscp.h>
  41
  42#define DRV_NAME	"vrf"
  43#define DRV_VERSION	"1.1"
  44
  45#define FIB_RULE_PREF  1000       /* default preference for FIB rules */
  46
  47#define HT_MAP_BITS	4
  48#define HASH_INITVAL	((u32)0xcafef00d)
  49
  50struct  vrf_map {
  51	DECLARE_HASHTABLE(ht, HT_MAP_BITS);
  52	spinlock_t vmap_lock;
  53
  54	/* shared_tables:
  55	 * count how many distinct tables do not comply with the strict mode
  56	 * requirement.
  57	 * shared_tables value must be 0 in order to enable the strict mode.
  58	 *
  59	 * example of the evolution of shared_tables:
  60	 *                                                        | time
  61	 * add  vrf0 --> table 100        shared_tables = 0       | t0
  62	 * add  vrf1 --> table 101        shared_tables = 0       | t1
  63	 * add  vrf2 --> table 100        shared_tables = 1       | t2
  64	 * add  vrf3 --> table 100        shared_tables = 1       | t3
  65	 * add  vrf4 --> table 101        shared_tables = 2       v t4
  66	 *
  67	 * shared_tables is a "step function" (or "staircase function")
  68	 * and it is increased by one when the second vrf is associated to a
  69	 * table.
  70	 *
  71	 * at t2, vrf0 and vrf2 are bound to table 100: shared_tables = 1.
  72	 *
  73	 * at t3, another dev (vrf3) is bound to the same table 100 but the
  74	 * value of shared_tables is still 1.
  75	 * This means that no matter how many new vrfs will register on the
  76	 * table 100, the shared_tables will not increase (considering only
  77	 * table 100).
  78	 *
  79	 * at t4, vrf4 is bound to table 101, and shared_tables = 2.
  80	 *
  81	 * Looking at the value of shared_tables we can immediately know if
  82	 * the strict_mode can or cannot be enforced. Indeed, strict_mode
  83	 * can be enforced iff shared_tables = 0.
  84	 *
  85	 * Conversely, shared_tables is decreased when a vrf is de-associated
  86	 * from a table with exactly two associated vrfs.
  87	 */
  88	u32 shared_tables;
  89
  90	bool strict_mode;
  91};
  92
  93struct vrf_map_elem {
  94	struct hlist_node hnode;
  95	struct list_head vrf_list;  /* VRFs registered to this table */
  96
  97	u32 table_id;
  98	int users;
  99	int ifindex;
 100};
 101
 102static unsigned int vrf_net_id;
 
 103
 104/* per netns vrf data */
 105struct netns_vrf {
 106	/* protected by rtnl lock */
 107	bool add_fib_rules;
 108
 109	struct vrf_map vmap;
 110	struct ctl_table_header	*ctl_hdr;
 111};
 112
 113struct net_vrf {
 114	struct rtable __rcu	*rth;
 115	struct rt6_info	__rcu	*rt6;
 116#if IS_ENABLED(CONFIG_IPV6)
 117	struct fib6_table	*fib6_table;
 118#endif
 119	u32                     tb_id;
 120
 121	struct list_head	me_list;   /* entry in vrf_map_elem */
 122	int			ifindex;
 123};
 124
 125static void vrf_rx_stats(struct net_device *dev, int len)
 126{
 127	struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 128
 129	u64_stats_update_begin(&dstats->syncp);
 130	u64_stats_inc(&dstats->rx_packets);
 131	u64_stats_add(&dstats->rx_bytes, len);
 132	u64_stats_update_end(&dstats->syncp);
 133}
 134
 135static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
 136{
 137	vrf_dev->stats.tx_errors++;
 138	kfree_skb(skb);
 139}
 140
 141static struct vrf_map *netns_vrf_map(struct net *net)
 142{
 143	struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
 144
 145	return &nn_vrf->vmap;
 146}
 147
 148static struct vrf_map *netns_vrf_map_by_dev(struct net_device *dev)
 149{
 150	return netns_vrf_map(dev_net(dev));
 151}
 152
 153static int vrf_map_elem_get_vrf_ifindex(struct vrf_map_elem *me)
 154{
 155	struct list_head *me_head = &me->vrf_list;
 156	struct net_vrf *vrf;
 157
 158	if (list_empty(me_head))
 159		return -ENODEV;
 160
 161	vrf = list_first_entry(me_head, struct net_vrf, me_list);
 162
 163	return vrf->ifindex;
 164}
 165
 166static struct vrf_map_elem *vrf_map_elem_alloc(gfp_t flags)
 167{
 168	struct vrf_map_elem *me;
 169
 170	me = kmalloc(sizeof(*me), flags);
 171	if (!me)
 172		return NULL;
 173
 174	return me;
 175}
 176
 177static void vrf_map_elem_free(struct vrf_map_elem *me)
 178{
 179	kfree(me);
 180}
 181
 182static void vrf_map_elem_init(struct vrf_map_elem *me, int table_id,
 183			      int ifindex, int users)
 184{
 185	me->table_id = table_id;
 186	me->ifindex = ifindex;
 187	me->users = users;
 188	INIT_LIST_HEAD(&me->vrf_list);
 189}
 190
 191static struct vrf_map_elem *vrf_map_lookup_elem(struct vrf_map *vmap,
 192						u32 table_id)
 193{
 194	struct vrf_map_elem *me;
 195	u32 key;
 196
 197	key = jhash_1word(table_id, HASH_INITVAL);
 198	hash_for_each_possible(vmap->ht, me, hnode, key) {
 199		if (me->table_id == table_id)
 200			return me;
 201	}
 202
 203	return NULL;
 204}
 205
 206static void vrf_map_add_elem(struct vrf_map *vmap, struct vrf_map_elem *me)
 207{
 208	u32 table_id = me->table_id;
 209	u32 key;
 210
 211	key = jhash_1word(table_id, HASH_INITVAL);
 212	hash_add(vmap->ht, &me->hnode, key);
 213}
 214
 215static void vrf_map_del_elem(struct vrf_map_elem *me)
 
 
 
 
 
 
 216{
 217	hash_del(&me->hnode);
 218}
 
 219
 220static void vrf_map_lock(struct vrf_map *vmap) __acquires(&vmap->vmap_lock)
 221{
 222	spin_lock(&vmap->vmap_lock);
 223}
 224
 225static void vrf_map_unlock(struct vrf_map *vmap) __releases(&vmap->vmap_lock)
 226{
 227	spin_unlock(&vmap->vmap_lock);
 228}
 229
 230/* called with rtnl lock held */
 231static int
 232vrf_map_register_dev(struct net_device *dev, struct netlink_ext_ack *extack)
 233{
 234	struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
 235	struct net_vrf *vrf = netdev_priv(dev);
 236	struct vrf_map_elem *new_me, *me;
 237	u32 table_id = vrf->tb_id;
 238	bool free_new_me = false;
 239	int users;
 240	int res;
 241
 242	/* we pre-allocate elements used in the spin-locked section (so that we
 243	 * keep the spinlock as short as possible).
 244	 */
 245	new_me = vrf_map_elem_alloc(GFP_KERNEL);
 246	if (!new_me)
 247		return -ENOMEM;
 248
 249	vrf_map_elem_init(new_me, table_id, dev->ifindex, 0);
 250
 251	vrf_map_lock(vmap);
 252
 253	me = vrf_map_lookup_elem(vmap, table_id);
 254	if (!me) {
 255		me = new_me;
 256		vrf_map_add_elem(vmap, me);
 257		goto link_vrf;
 258	}
 259
 260	/* we already have an entry in the vrf_map, so it means there is (at
 261	 * least) a vrf registered on the specific table.
 262	 */
 263	free_new_me = true;
 264	if (vmap->strict_mode) {
 265		/* vrfs cannot share the same table */
 266		NL_SET_ERR_MSG(extack, "Table is used by another VRF");
 267		res = -EBUSY;
 268		goto unlock;
 269	}
 270
 271link_vrf:
 272	users = ++me->users;
 273	if (users == 2)
 274		++vmap->shared_tables;
 275
 276	list_add(&vrf->me_list, &me->vrf_list);
 277
 278	res = 0;
 279
 280unlock:
 281	vrf_map_unlock(vmap);
 282
 283	/* clean-up, if needed */
 284	if (free_new_me)
 285		vrf_map_elem_free(new_me);
 286
 287	return res;
 288}
 289
 290/* called with rtnl lock held */
 291static void vrf_map_unregister_dev(struct net_device *dev)
 292{
 293	struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
 294	struct net_vrf *vrf = netdev_priv(dev);
 295	u32 table_id = vrf->tb_id;
 296	struct vrf_map_elem *me;
 297	int users;
 298
 299	vrf_map_lock(vmap);
 300
 301	me = vrf_map_lookup_elem(vmap, table_id);
 302	if (!me)
 303		goto unlock;
 304
 305	list_del(&vrf->me_list);
 306
 307	users = --me->users;
 308	if (users == 1) {
 309		--vmap->shared_tables;
 310	} else if (users == 0) {
 311		vrf_map_del_elem(me);
 312
 313		/* no one will refer to this element anymore */
 314		vrf_map_elem_free(me);
 315	}
 316
 317unlock:
 318	vrf_map_unlock(vmap);
 319}
 
 320
 321/* return the vrf device index associated with the table_id */
 322static int vrf_ifindex_lookup_by_table_id(struct net *net, u32 table_id)
 323{
 324	struct vrf_map *vmap = netns_vrf_map(net);
 325	struct vrf_map_elem *me;
 326	int ifindex;
 327
 328	vrf_map_lock(vmap);
 329
 330	if (!vmap->strict_mode) {
 331		ifindex = -EPERM;
 332		goto unlock;
 333	}
 334
 335	me = vrf_map_lookup_elem(vmap, table_id);
 336	if (!me) {
 337		ifindex = -ENODEV;
 338		goto unlock;
 339	}
 340
 341	ifindex = vrf_map_elem_get_vrf_ifindex(me);
 342
 343unlock:
 344	vrf_map_unlock(vmap);
 345
 346	return ifindex;
 347}
 348
 349/* by default VRF devices do not have a qdisc and are expected
 350 * to be created with only a single queue.
 351 */
 352static bool qdisc_tx_is_default(const struct net_device *dev)
 353{
 354	struct netdev_queue *txq;
 355	struct Qdisc *qdisc;
 356
 357	if (dev->num_tx_queues > 1)
 358		return false;
 359
 360	txq = netdev_get_tx_queue(dev, 0);
 361	qdisc = rcu_access_pointer(txq->qdisc);
 362
 363	return !qdisc->enqueue;
 364}
 365
 366/* Local traffic destined to local address. Reinsert the packet to rx
 367 * path, similar to loopback handling.
 368 */
 369static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
 370			  struct dst_entry *dst)
 371{
 372	int len = skb->len;
 373
 374	skb_orphan(skb);
 375
 376	skb_dst_set(skb, dst);
 377
 378	/* set pkt_type to avoid skb hitting packet taps twice -
 379	 * once on Tx and again in Rx processing
 380	 */
 381	skb->pkt_type = PACKET_LOOPBACK;
 382
 383	skb->protocol = eth_type_trans(skb, dev);
 384
 385	if (likely(__netif_rx(skb) == NET_RX_SUCCESS)) {
 386		vrf_rx_stats(dev, len);
 387	} else {
 388		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 389
 390		u64_stats_update_begin(&dstats->syncp);
 391		u64_stats_inc(&dstats->rx_drops);
 
 392		u64_stats_update_end(&dstats->syncp);
 393	}
 394
 395	return NETDEV_TX_OK;
 396}
 397
 398static void vrf_nf_set_untracked(struct sk_buff *skb)
 399{
 400	if (skb_get_nfct(skb) == 0)
 401		nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 402}
 403
 404static void vrf_nf_reset_ct(struct sk_buff *skb)
 405{
 406	if (skb_get_nfct(skb) == IP_CT_UNTRACKED)
 407		nf_reset_ct(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 408}
 409
 410#if IS_ENABLED(CONFIG_IPV6)
 411static int vrf_ip6_local_out(struct net *net, struct sock *sk,
 412			     struct sk_buff *skb)
 413{
 414	int err;
 415
 416	vrf_nf_reset_ct(skb);
 417
 418	err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
 419		      sk, skb, NULL, skb_dst(skb)->dev, dst_output);
 420
 421	if (likely(err == 1))
 422		err = dst_output(net, sk, skb);
 423
 424	return err;
 425}
 426
 427static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
 428					   struct net_device *dev)
 429{
 430	const struct ipv6hdr *iph;
 431	struct net *net = dev_net(skb->dev);
 432	struct flowi6 fl6;
 
 
 
 
 
 
 
 
 
 
 433	int ret = NET_XMIT_DROP;
 434	struct dst_entry *dst;
 435	struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
 436
 437	if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr)))
 438		goto err;
 439
 440	iph = ipv6_hdr(skb);
 441
 442	memset(&fl6, 0, sizeof(fl6));
 443	/* needed to match OIF rule */
 444	fl6.flowi6_l3mdev = dev->ifindex;
 445	fl6.flowi6_iif = LOOPBACK_IFINDEX;
 446	fl6.daddr = iph->daddr;
 447	fl6.saddr = iph->saddr;
 448	fl6.flowlabel = ip6_flowinfo(iph);
 449	fl6.flowi6_mark = skb->mark;
 450	fl6.flowi6_proto = iph->nexthdr;
 451
 452	dst = ip6_dst_lookup_flow(net, NULL, &fl6, NULL);
 453	if (IS_ERR(dst) || dst == dst_null)
 454		goto err;
 455
 456	skb_dst_drop(skb);
 457
 458	/* if dst.dev is the VRF device again this is locally originated traffic
 459	 * destined to a local address. Short circuit to Rx path.
 460	 */
 461	if (dst->dev == dev)
 462		return vrf_local_xmit(skb, dev, dst);
 463
 464	skb_dst_set(skb, dst);
 465
 466	/* strip the ethernet header added for pass through VRF device */
 467	__skb_pull(skb, skb_network_offset(skb));
 468
 469	memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
 470	ret = vrf_ip6_local_out(net, skb->sk, skb);
 471	if (unlikely(net_xmit_eval(ret)))
 472		dev->stats.tx_errors++;
 473	else
 474		ret = NET_XMIT_SUCCESS;
 475
 476	return ret;
 477err:
 478	vrf_tx_error(dev, skb);
 479	return NET_XMIT_DROP;
 480}
 481#else
 482static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
 483					   struct net_device *dev)
 484{
 485	vrf_tx_error(dev, skb);
 486	return NET_XMIT_DROP;
 487}
 488#endif
 489
 490/* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
 491static int vrf_ip_local_out(struct net *net, struct sock *sk,
 492			    struct sk_buff *skb)
 493{
 494	int err;
 495
 496	vrf_nf_reset_ct(skb);
 497
 498	err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
 499		      skb, NULL, skb_dst(skb)->dev, dst_output);
 500	if (likely(err == 1))
 501		err = dst_output(net, sk, skb);
 502
 
 
 
 
 
 
 
 
 
 
 503	return err;
 504}
 505
 506static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
 507					   struct net_device *vrf_dev)
 508{
 509	struct iphdr *ip4h;
 510	int ret = NET_XMIT_DROP;
 511	struct flowi4 fl4;
 512	struct net *net = dev_net(vrf_dev);
 513	struct rtable *rt;
 514
 515	if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr)))
 516		goto err;
 517
 518	ip4h = ip_hdr(skb);
 519
 520	memset(&fl4, 0, sizeof(fl4));
 521	/* needed to match OIF rule */
 522	fl4.flowi4_l3mdev = vrf_dev->ifindex;
 523	fl4.flowi4_iif = LOOPBACK_IFINDEX;
 524	fl4.flowi4_tos = inet_dscp_to_dsfield(ip4h_dscp(ip4h));
 525	fl4.flowi4_flags = FLOWI_FLAG_ANYSRC;
 526	fl4.flowi4_proto = ip4h->protocol;
 527	fl4.daddr = ip4h->daddr;
 528	fl4.saddr = ip4h->saddr;
 529
 530	rt = ip_route_output_flow(net, &fl4, NULL);
 531	if (IS_ERR(rt))
 532		goto err;
 533
 534	skb_dst_drop(skb);
 535
 536	/* if dst.dev is the VRF device again this is locally originated traffic
 537	 * destined to a local address. Short circuit to Rx path.
 538	 */
 539	if (rt->dst.dev == vrf_dev)
 540		return vrf_local_xmit(skb, vrf_dev, &rt->dst);
 541
 542	skb_dst_set(skb, &rt->dst);
 543
 544	/* strip the ethernet header added for pass through VRF device */
 545	__skb_pull(skb, skb_network_offset(skb));
 546
 547	if (!ip4h->saddr) {
 548		ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
 549					       RT_SCOPE_LINK);
 550	}
 551
 552	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 553	ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 554	if (unlikely(net_xmit_eval(ret)))
 555		vrf_dev->stats.tx_errors++;
 556	else
 557		ret = NET_XMIT_SUCCESS;
 558
 559out:
 560	return ret;
 561err:
 562	vrf_tx_error(vrf_dev, skb);
 563	goto out;
 564}
 565
 566static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
 567{
 
 
 
 568	switch (skb->protocol) {
 569	case htons(ETH_P_IP):
 570		return vrf_process_v4_outbound(skb, dev);
 571	case htons(ETH_P_IPV6):
 572		return vrf_process_v6_outbound(skb, dev);
 573	default:
 574		vrf_tx_error(dev, skb);
 575		return NET_XMIT_DROP;
 576	}
 577}
 578
 579static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
 580{
 581	struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 582
 583	int len = skb->len;
 584	netdev_tx_t ret = is_ip_tx_frame(skb, dev);
 585
 586	u64_stats_update_begin(&dstats->syncp);
 587	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 
 588
 589		u64_stats_inc(&dstats->tx_packets);
 590		u64_stats_add(&dstats->tx_bytes, len);
 
 
 591	} else {
 592		u64_stats_inc(&dstats->tx_drops);
 593	}
 594	u64_stats_update_end(&dstats->syncp);
 595
 596	return ret;
 597}
 598
 599static void vrf_finish_direct(struct sk_buff *skb)
 600{
 601	struct net_device *vrf_dev = skb->dev;
 602
 603	if (!list_empty(&vrf_dev->ptype_all) &&
 604	    likely(skb_headroom(skb) >= ETH_HLEN)) {
 605		struct ethhdr *eth = skb_push(skb, ETH_HLEN);
 606
 607		ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
 608		eth_zero_addr(eth->h_dest);
 609		eth->h_proto = skb->protocol;
 610
 611		rcu_read_lock_bh();
 612		dev_queue_xmit_nit(skb, vrf_dev);
 613		rcu_read_unlock_bh();
 614
 615		skb_pull(skb, ETH_HLEN);
 616	}
 617
 618	vrf_nf_reset_ct(skb);
 619}
 620
 621#if IS_ENABLED(CONFIG_IPV6)
 622/* modelled after ip6_finish_output2 */
 623static int vrf_finish_output6(struct net *net, struct sock *sk,
 624			      struct sk_buff *skb)
 625{
 626	struct dst_entry *dst = skb_dst(skb);
 627	struct net_device *dev = dst->dev;
 628	const struct in6_addr *nexthop;
 629	struct neighbour *neigh;
 
 630	int ret;
 631
 632	vrf_nf_reset_ct(skb);
 633
 634	skb->protocol = htons(ETH_P_IPV6);
 635	skb->dev = dev;
 636
 637	rcu_read_lock();
 638	nexthop = rt6_nexthop(dst_rt6_info(dst), &ipv6_hdr(skb)->daddr);
 639	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
 640	if (unlikely(!neigh))
 641		neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
 642	if (!IS_ERR(neigh)) {
 643		sock_confirm_neigh(skb, neigh);
 644		ret = neigh_output(neigh, skb, false);
 645		rcu_read_unlock();
 646		return ret;
 647	}
 648	rcu_read_unlock();
 649
 650	IP6_INC_STATS(dev_net(dst->dev),
 651		      ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
 652	kfree_skb(skb);
 653	return -EINVAL;
 654}
 655
 656/* modelled after ip6_output */
 657static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
 658{
 659	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
 660			    net, sk, skb, NULL, skb_dst(skb)->dev,
 661			    vrf_finish_output6,
 662			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
 663}
 664
 665/* set dst on skb to send packet to us via dev_xmit path. Allows
 666 * packet to go through device based features such as qdisc, netfilter
 667 * hooks and packet sockets with skb->dev set to vrf device.
 668 */
 669static struct sk_buff *vrf_ip6_out_redirect(struct net_device *vrf_dev,
 670					    struct sk_buff *skb)
 671{
 672	struct net_vrf *vrf = netdev_priv(vrf_dev);
 673	struct dst_entry *dst = NULL;
 674	struct rt6_info *rt6;
 675
 676	rcu_read_lock();
 677
 678	rt6 = rcu_dereference(vrf->rt6);
 679	if (likely(rt6)) {
 680		dst = &rt6->dst;
 681		dst_hold(dst);
 682	}
 683
 684	rcu_read_unlock();
 685
 686	if (unlikely(!dst)) {
 687		vrf_tx_error(vrf_dev, skb);
 688		return NULL;
 689	}
 690
 691	skb_dst_drop(skb);
 692	skb_dst_set(skb, dst);
 693
 694	return skb;
 695}
 696
 697static int vrf_output6_direct_finish(struct net *net, struct sock *sk,
 698				     struct sk_buff *skb)
 699{
 700	vrf_finish_direct(skb);
 701
 702	return vrf_ip6_local_out(net, sk, skb);
 703}
 704
 705static int vrf_output6_direct(struct net *net, struct sock *sk,
 706			      struct sk_buff *skb)
 707{
 708	int err = 1;
 709
 710	skb->protocol = htons(ETH_P_IPV6);
 711
 712	if (!(IPCB(skb)->flags & IPSKB_REROUTED))
 713		err = nf_hook(NFPROTO_IPV6, NF_INET_POST_ROUTING, net, sk, skb,
 714			      NULL, skb->dev, vrf_output6_direct_finish);
 715
 716	if (likely(err == 1))
 717		vrf_finish_direct(skb);
 718
 719	return err;
 720}
 721
 722static int vrf_ip6_out_direct_finish(struct net *net, struct sock *sk,
 723				     struct sk_buff *skb)
 724{
 725	int err;
 726
 727	err = vrf_output6_direct(net, sk, skb);
 728	if (likely(err == 1))
 729		err = vrf_ip6_local_out(net, sk, skb);
 730
 731	return err;
 732}
 733
 734static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
 735					  struct sock *sk,
 736					  struct sk_buff *skb)
 737{
 738	struct net *net = dev_net(vrf_dev);
 739	int err;
 740
 741	skb->dev = vrf_dev;
 742
 743	err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk,
 744		      skb, NULL, vrf_dev, vrf_ip6_out_direct_finish);
 745
 746	if (likely(err == 1))
 747		err = vrf_output6_direct(net, sk, skb);
 748
 749	if (likely(err == 1))
 750		return skb;
 751
 752	return NULL;
 753}
 754
 755static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
 756				   struct sock *sk,
 757				   struct sk_buff *skb)
 758{
 759	/* don't divert link scope packets */
 760	if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
 761		return skb;
 762
 763	vrf_nf_set_untracked(skb);
 764
 765	if (qdisc_tx_is_default(vrf_dev) ||
 766	    IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
 767		return vrf_ip6_out_direct(vrf_dev, sk, skb);
 768
 769	return vrf_ip6_out_redirect(vrf_dev, skb);
 770}
 771
 772/* holding rtnl */
 773static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
 774{
 775	struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
 776	struct net *net = dev_net(dev);
 777	struct dst_entry *dst;
 778
 779	RCU_INIT_POINTER(vrf->rt6, NULL);
 780	synchronize_rcu();
 781
 782	/* move dev in dst's to loopback so this VRF device can be deleted
 783	 * - based on dst_ifdown
 784	 */
 785	if (rt6) {
 786		dst = &rt6->dst;
 787		netdev_ref_replace(dst->dev, net->loopback_dev,
 788				   &dst->dev_tracker, GFP_KERNEL);
 789		dst->dev = net->loopback_dev;
 790		dst_release(dst);
 791	}
 792}
 793
 794static int vrf_rt6_create(struct net_device *dev)
 795{
 796	int flags = DST_NOPOLICY | DST_NOXFRM;
 797	struct net_vrf *vrf = netdev_priv(dev);
 798	struct net *net = dev_net(dev);
 799	struct rt6_info *rt6;
 800	int rc = -ENOMEM;
 801
 802	/* IPv6 can be CONFIG enabled and then disabled runtime */
 803	if (!ipv6_mod_enabled())
 804		return 0;
 805
 806	vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
 807	if (!vrf->fib6_table)
 808		goto out;
 809
 810	/* create a dst for routing packets out a VRF device */
 811	rt6 = ip6_dst_alloc(net, dev, flags);
 812	if (!rt6)
 813		goto out;
 814
 815	rt6->dst.output	= vrf_output6;
 816
 817	rcu_assign_pointer(vrf->rt6, rt6);
 818
 819	rc = 0;
 820out:
 821	return rc;
 822}
 823#else
 824static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
 825				   struct sock *sk,
 826				   struct sk_buff *skb)
 827{
 828	return skb;
 829}
 830
 831static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
 832{
 833}
 834
 835static int vrf_rt6_create(struct net_device *dev)
 836{
 837	return 0;
 838}
 839#endif
 840
 841/* modelled after ip_finish_output2 */
 842static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 843{
 844	struct dst_entry *dst = skb_dst(skb);
 845	struct rtable *rt = dst_rtable(dst);
 846	struct net_device *dev = dst->dev;
 847	unsigned int hh_len = LL_RESERVED_SPACE(dev);
 848	struct neighbour *neigh;
 849	bool is_v6gw = false;
 850
 851	vrf_nf_reset_ct(skb);
 852
 853	/* Be paranoid, rather than too clever. */
 854	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
 855		skb = skb_expand_head(skb, hh_len);
 856		if (!skb) {
 857			dev->stats.tx_errors++;
 858			return -ENOMEM;
 
 
 859		}
 860	}
 
 861
 862	rcu_read_lock();
 
 
 863
 864	neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
 865	if (!IS_ERR(neigh)) {
 866		int ret;
 867
 868		sock_confirm_neigh(skb, neigh);
 869		/* if crossing protocols, can not use the cached header */
 870		ret = neigh_output(neigh, skb, is_v6gw);
 871		rcu_read_unlock();
 872		return ret;
 873	}
 874
 875	rcu_read_unlock();
 876	vrf_tx_error(skb->dev, skb);
 877	return -EINVAL;
 
 
 878}
 879
 880static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 881{
 882	struct net_device *dev = skb_dst(skb)->dev;
 883
 884	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
 885
 886	skb->dev = dev;
 887	skb->protocol = htons(ETH_P_IP);
 888
 889	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
 890			    net, sk, skb, NULL, dev,
 891			    vrf_finish_output,
 892			    !(IPCB(skb)->flags & IPSKB_REROUTED));
 893}
 894
 895/* set dst on skb to send packet to us via dev_xmit path. Allows
 896 * packet to go through device based features such as qdisc, netfilter
 897 * hooks and packet sockets with skb->dev set to vrf device.
 898 */
 899static struct sk_buff *vrf_ip_out_redirect(struct net_device *vrf_dev,
 900					   struct sk_buff *skb)
 901{
 902	struct net_vrf *vrf = netdev_priv(vrf_dev);
 903	struct dst_entry *dst = NULL;
 904	struct rtable *rth;
 905
 906	rcu_read_lock();
 907
 908	rth = rcu_dereference(vrf->rth);
 909	if (likely(rth)) {
 910		dst = &rth->dst;
 911		dst_hold(dst);
 912	}
 913
 914	rcu_read_unlock();
 915
 916	if (unlikely(!dst)) {
 917		vrf_tx_error(vrf_dev, skb);
 918		return NULL;
 919	}
 920
 921	skb_dst_drop(skb);
 922	skb_dst_set(skb, dst);
 923
 924	return skb;
 925}
 926
 927static int vrf_output_direct_finish(struct net *net, struct sock *sk,
 928				    struct sk_buff *skb)
 929{
 930	vrf_finish_direct(skb);
 931
 932	return vrf_ip_local_out(net, sk, skb);
 933}
 934
 935static int vrf_output_direct(struct net *net, struct sock *sk,
 936			     struct sk_buff *skb)
 937{
 938	int err = 1;
 939
 940	skb->protocol = htons(ETH_P_IP);
 941
 942	if (!(IPCB(skb)->flags & IPSKB_REROUTED))
 943		err = nf_hook(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb,
 944			      NULL, skb->dev, vrf_output_direct_finish);
 945
 946	if (likely(err == 1))
 947		vrf_finish_direct(skb);
 948
 949	return err;
 950}
 951
 952static int vrf_ip_out_direct_finish(struct net *net, struct sock *sk,
 953				    struct sk_buff *skb)
 954{
 955	int err;
 956
 957	err = vrf_output_direct(net, sk, skb);
 958	if (likely(err == 1))
 959		err = vrf_ip_local_out(net, sk, skb);
 960
 961	return err;
 962}
 963
 964static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
 965					 struct sock *sk,
 966					 struct sk_buff *skb)
 967{
 968	struct net *net = dev_net(vrf_dev);
 969	int err;
 970
 971	skb->dev = vrf_dev;
 972
 973	err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
 974		      skb, NULL, vrf_dev, vrf_ip_out_direct_finish);
 975
 976	if (likely(err == 1))
 977		err = vrf_output_direct(net, sk, skb);
 978
 979	if (likely(err == 1))
 980		return skb;
 981
 982	return NULL;
 983}
 984
 985static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
 986				  struct sock *sk,
 987				  struct sk_buff *skb)
 988{
 989	/* don't divert multicast or local broadcast */
 990	if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
 991	    ipv4_is_lbcast(ip_hdr(skb)->daddr))
 992		return skb;
 993
 994	vrf_nf_set_untracked(skb);
 995
 996	if (qdisc_tx_is_default(vrf_dev) ||
 997	    IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
 998		return vrf_ip_out_direct(vrf_dev, sk, skb);
 999
1000	return vrf_ip_out_redirect(vrf_dev, skb);
1001}
1002
1003/* called with rcu lock held */
1004static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
1005				  struct sock *sk,
1006				  struct sk_buff *skb,
1007				  u16 proto)
1008{
1009	switch (proto) {
1010	case AF_INET:
1011		return vrf_ip_out(vrf_dev, sk, skb);
1012	case AF_INET6:
1013		return vrf_ip6_out(vrf_dev, sk, skb);
1014	}
1015
1016	return skb;
 
1017}
1018
1019/* holding rtnl */
1020static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
1021{
1022	struct rtable *rth = rtnl_dereference(vrf->rth);
1023	struct net *net = dev_net(dev);
1024	struct dst_entry *dst;
1025
1026	RCU_INIT_POINTER(vrf->rth, NULL);
1027	synchronize_rcu();
1028
1029	/* move dev in dst's to loopback so this VRF device can be deleted
1030	 * - based on dst_ifdown
1031	 */
1032	if (rth) {
1033		dst = &rth->dst;
1034		netdev_ref_replace(dst->dev, net->loopback_dev,
1035				   &dst->dev_tracker, GFP_KERNEL);
1036		dst->dev = net->loopback_dev;
1037		dst_release(dst);
1038	}
1039}
1040
1041static int vrf_rtable_create(struct net_device *dev)
1042{
1043	struct net_vrf *vrf = netdev_priv(dev);
1044	struct rtable *rth;
1045
1046	if (!fib_new_table(dev_net(dev), vrf->tb_id))
1047		return -ENOMEM;
1048
1049	/* create a dst for routing packets out through a VRF device */
1050	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1);
1051	if (!rth)
1052		return -ENOMEM;
1053
1054	rth->dst.output	= vrf_output;
1055
1056	rcu_assign_pointer(vrf->rth, rth);
1057
1058	return 0;
1059}
1060
1061/**************************** device handling ********************/
1062
1063/* cycle interface to flush neighbor cache and move routes across tables */
1064static void cycle_netdev(struct net_device *dev,
1065			 struct netlink_ext_ack *extack)
1066{
1067	unsigned int flags = dev->flags;
1068	int ret;
1069
1070	if (!netif_running(dev))
1071		return;
1072
1073	ret = dev_change_flags(dev, flags & ~IFF_UP, extack);
1074	if (ret >= 0)
1075		ret = dev_change_flags(dev, flags, extack);
1076
1077	if (ret < 0) {
1078		netdev_err(dev,
1079			   "Failed to cycle device %s; route tables might be wrong!\n",
1080			   dev->name);
1081	}
1082}
1083
1084static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
1085			    struct netlink_ext_ack *extack)
1086{
1087	int ret;
1088
1089	/* do not allow loopback device to be enslaved to a VRF.
1090	 * The vrf device acts as the loopback for the vrf.
1091	 */
1092	if (port_dev == dev_net(dev)->loopback_dev) {
1093		NL_SET_ERR_MSG(extack,
1094			       "Can not enslave loopback device to a VRF");
1095		return -EOPNOTSUPP;
1096	}
1097
1098	port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
1099	ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
1100	if (ret < 0)
1101		goto err;
1102
1103	cycle_netdev(port_dev, extack);
 
1104
1105	return 0;
1106
1107err:
1108	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
 
1109	return ret;
1110}
1111
1112static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
1113			 struct netlink_ext_ack *extack)
1114{
1115	if (netif_is_l3_master(port_dev)) {
1116		NL_SET_ERR_MSG(extack,
1117			       "Can not enslave an L3 master device to a VRF");
1118		return -EINVAL;
1119	}
1120
1121	if (netif_is_l3_slave(port_dev))
1122		return -EINVAL;
1123
1124	return do_vrf_add_slave(dev, port_dev, extack);
1125}
1126
1127/* inverse of do_vrf_add_slave */
1128static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
1129{
1130	netdev_upper_dev_unlink(port_dev, dev);
1131	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
1132
1133	cycle_netdev(port_dev, NULL);
 
 
1134
1135	return 0;
1136}
1137
1138static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
1139{
1140	return do_vrf_del_slave(dev, port_dev);
1141}
1142
1143static void vrf_dev_uninit(struct net_device *dev)
1144{
1145	struct net_vrf *vrf = netdev_priv(dev);
 
 
 
 
 
 
 
 
1146
1147	vrf_rtable_release(dev, vrf);
1148	vrf_rt6_release(dev, vrf);
1149}
1150
1151static int vrf_dev_init(struct net_device *dev)
1152{
1153	struct net_vrf *vrf = netdev_priv(dev);
1154
1155	/* create the default dst which points back to us */
1156	if (vrf_rtable_create(dev) != 0)
1157		goto out_nomem;
1158
 
 
 
 
 
1159	if (vrf_rt6_create(dev) != 0)
1160		goto out_rth;
1161
1162	dev->flags = IFF_MASTER | IFF_NOARP;
1163
1164	/* similarly, oper state is irrelevant; set to up to avoid confusion */
1165	dev->operstate = IF_OPER_UP;
1166	netdev_lockdep_set_classes(dev);
1167	return 0;
1168
1169out_rth:
1170	vrf_rtable_release(dev, vrf);
 
 
 
1171out_nomem:
1172	return -ENOMEM;
1173}
1174
1175static const struct net_device_ops vrf_netdev_ops = {
1176	.ndo_init		= vrf_dev_init,
1177	.ndo_uninit		= vrf_dev_uninit,
1178	.ndo_start_xmit		= vrf_xmit,
1179	.ndo_set_mac_address	= eth_mac_addr,
1180	.ndo_add_slave		= vrf_add_slave,
1181	.ndo_del_slave		= vrf_del_slave,
1182};
1183
1184static u32 vrf_fib_table(const struct net_device *dev)
1185{
1186	struct net_vrf *vrf = netdev_priv(dev);
1187
1188	return vrf->tb_id;
1189}
1190
1191static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
1192{
1193	kfree_skb(skb);
1194	return 0;
1195}
1196
1197static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
1198				      struct sk_buff *skb,
1199				      struct net_device *dev)
1200{
1201	struct net *net = dev_net(dev);
1202
1203	if (nf_hook(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) != 1)
1204		skb = NULL;    /* kfree_skb(skb) handled by nf code */
1205
1206	return skb;
1207}
1208
1209static int vrf_prepare_mac_header(struct sk_buff *skb,
1210				  struct net_device *vrf_dev, u16 proto)
1211{
1212	struct ethhdr *eth;
1213	int err;
1214
1215	/* in general, we do not know if there is enough space in the head of
1216	 * the packet for hosting the mac header.
1217	 */
1218	err = skb_cow_head(skb, LL_RESERVED_SPACE(vrf_dev));
1219	if (unlikely(err))
1220		/* no space in the skb head */
1221		return -ENOBUFS;
1222
1223	__skb_push(skb, ETH_HLEN);
1224	eth = (struct ethhdr *)skb->data;
1225
1226	skb_reset_mac_header(skb);
1227	skb_reset_mac_len(skb);
1228
1229	/* we set the ethernet destination and the source addresses to the
1230	 * address of the VRF device.
1231	 */
1232	ether_addr_copy(eth->h_dest, vrf_dev->dev_addr);
1233	ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
1234	eth->h_proto = htons(proto);
1235
1236	/* the destination address of the Ethernet frame corresponds to the
1237	 * address set on the VRF interface; therefore, the packet is intended
1238	 * to be processed locally.
1239	 */
1240	skb->protocol = eth->h_proto;
1241	skb->pkt_type = PACKET_HOST;
1242
1243	skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
1244
1245	skb_pull_inline(skb, ETH_HLEN);
1246
1247	return 0;
1248}
1249
1250/* prepare and add the mac header to the packet if it was not set previously.
1251 * In this way, packet sniffers such as tcpdump can parse the packet correctly.
1252 * If the mac header was already set, the original mac header is left
1253 * untouched and the function returns immediately.
1254 */
1255static int vrf_add_mac_header_if_unset(struct sk_buff *skb,
1256				       struct net_device *vrf_dev,
1257				       u16 proto, struct net_device *orig_dev)
1258{
1259	if (skb_mac_header_was_set(skb) && dev_has_header(orig_dev))
1260		return 0;
1261
1262	return vrf_prepare_mac_header(skb, vrf_dev, proto);
1263}
1264
1265#if IS_ENABLED(CONFIG_IPV6)
1266/* neighbor handling is done with actual device; do not want
1267 * to flip skb->dev for those ndisc packets. This really fails
1268 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
1269 * a start.
1270 */
1271static bool ipv6_ndisc_frame(const struct sk_buff *skb)
1272{
1273	const struct ipv6hdr *iph = ipv6_hdr(skb);
1274	bool rc = false;
1275
1276	if (iph->nexthdr == NEXTHDR_ICMP) {
1277		const struct icmp6hdr *icmph;
1278		struct icmp6hdr _icmph;
1279
1280		icmph = skb_header_pointer(skb, sizeof(*iph),
1281					   sizeof(_icmph), &_icmph);
1282		if (!icmph)
1283			goto out;
1284
1285		switch (icmph->icmp6_type) {
1286		case NDISC_ROUTER_SOLICITATION:
1287		case NDISC_ROUTER_ADVERTISEMENT:
1288		case NDISC_NEIGHBOUR_SOLICITATION:
1289		case NDISC_NEIGHBOUR_ADVERTISEMENT:
1290		case NDISC_REDIRECT:
1291			rc = true;
1292			break;
1293		}
1294	}
1295
1296out:
1297	return rc;
1298}
1299
1300static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
1301					     const struct net_device *dev,
1302					     struct flowi6 *fl6,
1303					     int ifindex,
1304					     const struct sk_buff *skb,
1305					     int flags)
1306{
1307	struct net_vrf *vrf = netdev_priv(dev);
1308
1309	return ip6_pol_route(net, vrf->fib6_table, ifindex, fl6, skb, flags);
1310}
1311
1312static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
1313			      int ifindex)
1314{
1315	const struct ipv6hdr *iph = ipv6_hdr(skb);
1316	struct flowi6 fl6 = {
1317		.flowi6_iif     = ifindex,
1318		.flowi6_mark    = skb->mark,
1319		.flowi6_proto   = iph->nexthdr,
1320		.daddr          = iph->daddr,
1321		.saddr          = iph->saddr,
1322		.flowlabel      = ip6_flowinfo(iph),
1323	};
1324	struct net *net = dev_net(vrf_dev);
1325	struct rt6_info *rt6;
1326
1327	rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex, skb,
1328				   RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
1329	if (unlikely(!rt6))
1330		return;
1331
1332	if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
1333		return;
1334
1335	skb_dst_set(skb, &rt6->dst);
1336}
1337
1338static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1339				   struct sk_buff *skb)
1340{
1341	int orig_iif = skb->skb_iif;
1342	bool need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
1343	bool is_ndisc = ipv6_ndisc_frame(skb);
1344
1345	/* loopback, multicast & non-ND link-local traffic; do not push through
1346	 * packet taps again. Reset pkt_type for upper layers to process skb.
1347	 * For non-loopback strict packets, determine the dst using the original
1348	 * ifindex.
1349	 */
1350	if (skb->pkt_type == PACKET_LOOPBACK || (need_strict && !is_ndisc)) {
1351		skb->dev = vrf_dev;
1352		skb->skb_iif = vrf_dev->ifindex;
1353		IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1354
1355		if (skb->pkt_type == PACKET_LOOPBACK)
1356			skb->pkt_type = PACKET_HOST;
 
 
 
 
 
 
 
 
1357		else
1358			vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1359
1360		goto out;
1361	}
1362
1363	/* if packet is NDISC then keep the ingress interface */
1364	if (!is_ndisc) {
1365		struct net_device *orig_dev = skb->dev;
1366
1367		vrf_rx_stats(vrf_dev, skb->len);
1368		skb->dev = vrf_dev;
1369		skb->skb_iif = vrf_dev->ifindex;
1370
1371		if (!list_empty(&vrf_dev->ptype_all)) {
1372			int err;
1373
1374			err = vrf_add_mac_header_if_unset(skb, vrf_dev,
1375							  ETH_P_IPV6,
1376							  orig_dev);
1377			if (likely(!err)) {
1378				skb_push(skb, skb->mac_len);
1379				dev_queue_xmit_nit(skb, vrf_dev);
1380				skb_pull(skb, skb->mac_len);
1381			}
1382		}
1383
1384		IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1385	}
1386
1387	if (need_strict)
1388		vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1389
1390	skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1391out:
1392	return skb;
1393}
1394
1395#else
1396static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1397				   struct sk_buff *skb)
1398{
1399	return skb;
1400}
1401#endif
1402
1403static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1404				  struct sk_buff *skb)
1405{
1406	struct net_device *orig_dev = skb->dev;
1407
1408	skb->dev = vrf_dev;
1409	skb->skb_iif = vrf_dev->ifindex;
1410	IPCB(skb)->flags |= IPSKB_L3SLAVE;
1411
1412	if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1413		goto out;
1414
1415	/* loopback traffic; do not push through packet taps again.
1416	 * Reset pkt_type for upper layers to process skb
1417	 */
1418	if (skb->pkt_type == PACKET_LOOPBACK) {
1419		skb->pkt_type = PACKET_HOST;
1420		goto out;
1421	}
1422
1423	vrf_rx_stats(vrf_dev, skb->len);
1424
1425	if (!list_empty(&vrf_dev->ptype_all)) {
1426		int err;
1427
1428		err = vrf_add_mac_header_if_unset(skb, vrf_dev, ETH_P_IP,
1429						  orig_dev);
1430		if (likely(!err)) {
1431			skb_push(skb, skb->mac_len);
1432			dev_queue_xmit_nit(skb, vrf_dev);
1433			skb_pull(skb, skb->mac_len);
1434		}
1435	}
1436
1437	skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1438out:
1439	return skb;
1440}
1441
1442/* called with rcu lock held */
1443static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1444				  struct sk_buff *skb,
1445				  u16 proto)
1446{
1447	switch (proto) {
1448	case AF_INET:
1449		return vrf_ip_rcv(vrf_dev, skb);
1450	case AF_INET6:
1451		return vrf_ip6_rcv(vrf_dev, skb);
1452	}
1453
1454	return skb;
1455}
1456
1457#if IS_ENABLED(CONFIG_IPV6)
1458/* send to link-local or multicast address via interface enslaved to
1459 * VRF device. Force lookup to VRF table without changing flow struct
1460 * Note: Caller to this function must hold rcu_read_lock() and no refcnt
1461 * is taken on the dst by this function.
1462 */
1463static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1464					      struct flowi6 *fl6)
1465{
1466	struct net *net = dev_net(dev);
1467	int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_DST_NOREF;
1468	struct dst_entry *dst = NULL;
1469	struct rt6_info *rt;
1470
1471	/* VRF device does not have a link-local address and
1472	 * sending packets to link-local or mcast addresses over
1473	 * a VRF device does not make sense
1474	 */
1475	if (fl6->flowi6_oif == dev->ifindex) {
1476		dst = &net->ipv6.ip6_null_entry->dst;
1477		return dst;
1478	}
1479
1480	if (!ipv6_addr_any(&fl6->saddr))
1481		flags |= RT6_LOOKUP_F_HAS_SADDR;
1482
1483	rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
1484	if (rt)
1485		dst = &rt->dst;
1486
1487	return dst;
1488}
1489#endif
1490
1491static const struct l3mdev_ops vrf_l3mdev_ops = {
1492	.l3mdev_fib_table	= vrf_fib_table,
1493	.l3mdev_l3_rcv		= vrf_l3_rcv,
1494	.l3mdev_l3_out		= vrf_l3_out,
1495#if IS_ENABLED(CONFIG_IPV6)
1496	.l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1497#endif
1498};
1499
1500static void vrf_get_drvinfo(struct net_device *dev,
1501			    struct ethtool_drvinfo *info)
1502{
1503	strscpy(info->driver, DRV_NAME, sizeof(info->driver));
1504	strscpy(info->version, DRV_VERSION, sizeof(info->version));
1505}
1506
1507static const struct ethtool_ops vrf_ethtool_ops = {
1508	.get_drvinfo	= vrf_get_drvinfo,
1509};
1510
1511static inline size_t vrf_fib_rule_nl_size(void)
1512{
1513	size_t sz;
1514
1515	sz  = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1516	sz += nla_total_size(sizeof(u8));	/* FRA_L3MDEV */
1517	sz += nla_total_size(sizeof(u32));	/* FRA_PRIORITY */
1518	sz += nla_total_size(sizeof(u8));       /* FRA_PROTOCOL */
1519
1520	return sz;
1521}
1522
1523static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1524{
1525	struct fib_rule_hdr *frh;
1526	struct nlmsghdr *nlh;
1527	struct sk_buff *skb;
1528	int err;
1529
1530	if ((family == AF_INET6 || family == RTNL_FAMILY_IP6MR) &&
1531	    !ipv6_mod_enabled())
1532		return 0;
1533
1534	skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1535	if (!skb)
1536		return -ENOMEM;
1537
1538	nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1539	if (!nlh)
1540		goto nla_put_failure;
1541
1542	/* rule only needs to appear once */
1543	nlh->nlmsg_flags |= NLM_F_EXCL;
1544
1545	frh = nlmsg_data(nlh);
1546	memset(frh, 0, sizeof(*frh));
1547	frh->family = family;
1548	frh->action = FR_ACT_TO_TBL;
1549
1550	if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
1551		goto nla_put_failure;
1552
1553	if (nla_put_u8(skb, FRA_L3MDEV, 1))
1554		goto nla_put_failure;
1555
1556	if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1557		goto nla_put_failure;
1558
1559	nlmsg_end(skb, nlh);
1560
1561	/* fib_nl_{new,del}rule handling looks for net from skb->sk */
1562	skb->sk = dev_net(dev)->rtnl;
1563	if (add_it) {
1564		err = fib_nl_newrule(skb, nlh, NULL);
1565		if (err == -EEXIST)
1566			err = 0;
1567	} else {
1568		err = fib_nl_delrule(skb, nlh, NULL);
1569		if (err == -ENOENT)
1570			err = 0;
1571	}
1572	nlmsg_free(skb);
1573
1574	return err;
1575
1576nla_put_failure:
1577	nlmsg_free(skb);
1578
1579	return -EMSGSIZE;
1580}
1581
1582static int vrf_add_fib_rules(const struct net_device *dev)
1583{
1584	int err;
1585
1586	err = vrf_fib_rule(dev, AF_INET,  true);
1587	if (err < 0)
1588		goto out_err;
1589
1590	err = vrf_fib_rule(dev, AF_INET6, true);
1591	if (err < 0)
1592		goto ipv6_err;
1593
1594#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1595	err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1596	if (err < 0)
1597		goto ipmr_err;
1598#endif
1599
1600#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1601	err = vrf_fib_rule(dev, RTNL_FAMILY_IP6MR, true);
1602	if (err < 0)
1603		goto ip6mr_err;
1604#endif
1605
1606	return 0;
1607
1608#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1609ip6mr_err:
1610	vrf_fib_rule(dev, RTNL_FAMILY_IPMR,  false);
1611#endif
1612
1613#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1614ipmr_err:
1615	vrf_fib_rule(dev, AF_INET6,  false);
1616#endif
1617
1618ipv6_err:
1619	vrf_fib_rule(dev, AF_INET,  false);
1620
1621out_err:
1622	netdev_err(dev, "Failed to add FIB rules.\n");
1623	return err;
1624}
1625
1626static void vrf_setup(struct net_device *dev)
1627{
1628	ether_setup(dev);
1629
1630	/* Initialize the device structure. */
1631	dev->netdev_ops = &vrf_netdev_ops;
1632	dev->l3mdev_ops = &vrf_l3mdev_ops;
1633	dev->ethtool_ops = &vrf_ethtool_ops;
1634	dev->needs_free_netdev = true;
1635
1636	/* Fill in device structure with ethernet-generic values. */
1637	eth_hw_addr_random(dev);
1638
1639	/* don't acquire vrf device's netif_tx_lock when transmitting */
1640	dev->lltx = true;
1641
1642	/* don't allow vrf devices to change network namespaces. */
1643	dev->netns_local = true;
1644
1645	/* does not make sense for a VLAN to be added to a vrf device */
1646	dev->features   |= NETIF_F_VLAN_CHALLENGED;
1647
1648	/* enable offload features */
1649	dev->features   |= NETIF_F_GSO_SOFTWARE;
1650	dev->features   |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
1651	dev->features   |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1652
1653	dev->hw_features = dev->features;
1654	dev->hw_enc_features = dev->features;
1655
1656	/* default to no qdisc; user can add if desired */
1657	dev->priv_flags |= IFF_NO_QUEUE;
1658	dev->priv_flags |= IFF_NO_RX_HANDLER;
1659	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1660
1661	/* VRF devices do not care about MTU, but if the MTU is set
1662	 * too low then the ipv4 and ipv6 protocols are disabled
1663	 * which breaks networking.
1664	 */
1665	dev->min_mtu = IPV6_MIN_MTU;
1666	dev->max_mtu = IP6_MAX_MTU;
1667	dev->mtu = dev->max_mtu;
1668
1669	dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
1670}
1671
1672static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
1673			struct netlink_ext_ack *extack)
1674{
1675	if (tb[IFLA_ADDRESS]) {
1676		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1677			NL_SET_ERR_MSG(extack, "Invalid hardware address");
1678			return -EINVAL;
1679		}
1680		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1681			NL_SET_ERR_MSG(extack, "Invalid hardware address");
1682			return -EADDRNOTAVAIL;
1683		}
1684	}
1685	return 0;
1686}
1687
1688static void vrf_dellink(struct net_device *dev, struct list_head *head)
1689{
1690	struct net_device *port_dev;
1691	struct list_head *iter;
1692
1693	netdev_for_each_lower_dev(dev, port_dev, iter)
1694		vrf_del_slave(dev, port_dev);
1695
1696	vrf_map_unregister_dev(dev);
1697
1698	unregister_netdevice_queue(dev, head);
1699}
1700
1701static int vrf_newlink(struct net *src_net, struct net_device *dev,
1702		       struct nlattr *tb[], struct nlattr *data[],
1703		       struct netlink_ext_ack *extack)
1704{
1705	struct net_vrf *vrf = netdev_priv(dev);
1706	struct netns_vrf *nn_vrf;
1707	bool *add_fib_rules;
1708	struct net *net;
1709	int err;
1710
1711	if (!data || !data[IFLA_VRF_TABLE]) {
1712		NL_SET_ERR_MSG(extack, "VRF table id is missing");
1713		return -EINVAL;
1714	}
1715
1716	vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1717	if (vrf->tb_id == RT_TABLE_UNSPEC) {
1718		NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
1719				    "Invalid VRF table id");
1720		return -EINVAL;
1721	}
1722
1723	dev->priv_flags |= IFF_L3MDEV_MASTER;
1724
1725	err = register_netdevice(dev);
1726	if (err)
1727		goto out;
1728
1729	/* mapping between table_id and vrf;
1730	 * note: such binding could not be done in the dev init function
1731	 * because dev->ifindex id is not available yet.
1732	 */
1733	vrf->ifindex = dev->ifindex;
1734
1735	err = vrf_map_register_dev(dev, extack);
1736	if (err) {
1737		unregister_netdevice(dev);
1738		goto out;
1739	}
1740
1741	net = dev_net(dev);
1742	nn_vrf = net_generic(net, vrf_net_id);
1743
1744	add_fib_rules = &nn_vrf->add_fib_rules;
1745	if (*add_fib_rules) {
1746		err = vrf_add_fib_rules(dev);
1747		if (err) {
1748			vrf_map_unregister_dev(dev);
1749			unregister_netdevice(dev);
1750			goto out;
1751		}
1752		*add_fib_rules = false;
1753	}
1754
1755out:
1756	return err;
1757}
1758
1759static size_t vrf_nl_getsize(const struct net_device *dev)
1760{
1761	return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
1762}
1763
1764static int vrf_fillinfo(struct sk_buff *skb,
1765			const struct net_device *dev)
1766{
1767	struct net_vrf *vrf = netdev_priv(dev);
1768
1769	return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1770}
1771
1772static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1773				 const struct net_device *slave_dev)
1774{
1775	return nla_total_size(sizeof(u32));  /* IFLA_VRF_PORT_TABLE */
1776}
1777
1778static int vrf_fill_slave_info(struct sk_buff *skb,
1779			       const struct net_device *vrf_dev,
1780			       const struct net_device *slave_dev)
1781{
1782	struct net_vrf *vrf = netdev_priv(vrf_dev);
1783
1784	if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1785		return -EMSGSIZE;
1786
1787	return 0;
1788}
1789
1790static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1791	[IFLA_VRF_TABLE] = { .type = NLA_U32 },
1792};
1793
1794static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1795	.kind		= DRV_NAME,
1796	.priv_size	= sizeof(struct net_vrf),
1797
1798	.get_size	= vrf_nl_getsize,
1799	.policy		= vrf_nl_policy,
1800	.validate	= vrf_validate,
1801	.fill_info	= vrf_fillinfo,
1802
1803	.get_slave_size  = vrf_get_slave_size,
1804	.fill_slave_info = vrf_fill_slave_info,
1805
1806	.newlink	= vrf_newlink,
1807	.dellink	= vrf_dellink,
1808	.setup		= vrf_setup,
1809	.maxtype	= IFLA_VRF_MAX,
1810};
1811
1812static int vrf_device_event(struct notifier_block *unused,
1813			    unsigned long event, void *ptr)
1814{
1815	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1816
1817	/* only care about unregister events to drop slave references */
1818	if (event == NETDEV_UNREGISTER) {
1819		struct net_device *vrf_dev;
1820
1821		if (!netif_is_l3_slave(dev))
1822			goto out;
1823
1824		vrf_dev = netdev_master_upper_dev_get(dev);
1825		vrf_del_slave(vrf_dev, dev);
1826	}
1827out:
1828	return NOTIFY_DONE;
1829}
1830
1831static struct notifier_block vrf_notifier_block __read_mostly = {
1832	.notifier_call = vrf_device_event,
1833};
1834
1835static int vrf_map_init(struct vrf_map *vmap)
1836{
1837	spin_lock_init(&vmap->vmap_lock);
1838	hash_init(vmap->ht);
1839
1840	vmap->strict_mode = false;
1841
1842	return 0;
1843}
1844
1845#ifdef CONFIG_SYSCTL
1846static bool vrf_strict_mode(struct vrf_map *vmap)
1847{
1848	bool strict_mode;
1849
1850	vrf_map_lock(vmap);
1851	strict_mode = vmap->strict_mode;
1852	vrf_map_unlock(vmap);
1853
1854	return strict_mode;
1855}
1856
1857static int vrf_strict_mode_change(struct vrf_map *vmap, bool new_mode)
1858{
1859	bool *cur_mode;
1860	int res = 0;
1861
1862	vrf_map_lock(vmap);
1863
1864	cur_mode = &vmap->strict_mode;
1865	if (*cur_mode == new_mode)
1866		goto unlock;
1867
1868	if (*cur_mode) {
1869		/* disable strict mode */
1870		*cur_mode = false;
1871	} else {
1872		if (vmap->shared_tables) {
1873			/* we cannot allow strict_mode because there are some
1874			 * vrfs that share one or more tables.
1875			 */
1876			res = -EBUSY;
1877			goto unlock;
1878		}
1879
1880		/* no tables are shared among vrfs, so we can go back
1881		 * to 1:1 association between a vrf with its table.
1882		 */
1883		*cur_mode = true;
1884	}
1885
1886unlock:
1887	vrf_map_unlock(vmap);
1888
1889	return res;
1890}
1891
1892static int vrf_shared_table_handler(const struct ctl_table *table, int write,
1893				    void *buffer, size_t *lenp, loff_t *ppos)
1894{
1895	struct net *net = (struct net *)table->extra1;
1896	struct vrf_map *vmap = netns_vrf_map(net);
1897	int proc_strict_mode = 0;
1898	struct ctl_table tmp = {
1899		.procname	= table->procname,
1900		.data		= &proc_strict_mode,
1901		.maxlen		= sizeof(int),
1902		.mode		= table->mode,
1903		.extra1		= SYSCTL_ZERO,
1904		.extra2		= SYSCTL_ONE,
1905	};
1906	int ret;
1907
1908	if (!write)
1909		proc_strict_mode = vrf_strict_mode(vmap);
1910
1911	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
1912
1913	if (write && ret == 0)
1914		ret = vrf_strict_mode_change(vmap, (bool)proc_strict_mode);
1915
1916	return ret;
1917}
1918
1919static const struct ctl_table vrf_table[] = {
1920	{
1921		.procname	= "strict_mode",
1922		.data		= NULL,
1923		.maxlen		= sizeof(int),
1924		.mode		= 0644,
1925		.proc_handler	= vrf_shared_table_handler,
1926		/* set by the vrf_netns_init */
1927		.extra1		= NULL,
1928	},
1929};
1930
1931static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
1932{
1933	struct ctl_table *table;
1934
1935	table = kmemdup(vrf_table, sizeof(vrf_table), GFP_KERNEL);
1936	if (!table)
1937		return -ENOMEM;
1938
1939	/* init the extra1 parameter with the reference to current netns */
1940	table[0].extra1 = net;
1941
1942	nn_vrf->ctl_hdr = register_net_sysctl_sz(net, "net/vrf", table,
1943						 ARRAY_SIZE(vrf_table));
1944	if (!nn_vrf->ctl_hdr) {
1945		kfree(table);
1946		return -ENOMEM;
1947	}
1948
1949	return 0;
1950}
1951
1952static void vrf_netns_exit_sysctl(struct net *net)
1953{
1954	struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
1955	const struct ctl_table *table;
1956
1957	table = nn_vrf->ctl_hdr->ctl_table_arg;
1958	unregister_net_sysctl_table(nn_vrf->ctl_hdr);
1959	kfree(table);
1960}
1961#else
1962static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
1963{
1964	return 0;
1965}
1966
1967static void vrf_netns_exit_sysctl(struct net *net)
1968{
1969}
1970#endif
1971
1972/* Initialize per network namespace state */
1973static int __net_init vrf_netns_init(struct net *net)
1974{
1975	struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
1976
1977	nn_vrf->add_fib_rules = true;
1978	vrf_map_init(&nn_vrf->vmap);
1979
1980	return vrf_netns_init_sysctl(net, nn_vrf);
1981}
1982
1983static void __net_exit vrf_netns_exit(struct net *net)
1984{
1985	vrf_netns_exit_sysctl(net);
1986}
1987
1988static struct pernet_operations vrf_net_ops __net_initdata = {
1989	.init = vrf_netns_init,
1990	.exit = vrf_netns_exit,
1991	.id   = &vrf_net_id,
1992	.size = sizeof(struct netns_vrf),
1993};
1994
1995static int __init vrf_init_module(void)
1996{
1997	int rc;
1998
1999	register_netdevice_notifier(&vrf_notifier_block);
2000
2001	rc = register_pernet_subsys(&vrf_net_ops);
2002	if (rc < 0)
2003		goto error;
2004
2005	rc = l3mdev_table_lookup_register(L3MDEV_TYPE_VRF,
2006					  vrf_ifindex_lookup_by_table_id);
2007	if (rc < 0)
2008		goto unreg_pernet;
2009
2010	rc = rtnl_link_register(&vrf_link_ops);
2011	if (rc < 0)
2012		goto table_lookup_unreg;
2013
2014	return 0;
2015
2016table_lookup_unreg:
2017	l3mdev_table_lookup_unregister(L3MDEV_TYPE_VRF,
2018				       vrf_ifindex_lookup_by_table_id);
2019
2020unreg_pernet:
2021	unregister_pernet_subsys(&vrf_net_ops);
2022
2023error:
2024	unregister_netdevice_notifier(&vrf_notifier_block);
2025	return rc;
2026}
2027
2028module_init(vrf_init_module);
2029MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
2030MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
2031MODULE_LICENSE("GPL");
2032MODULE_ALIAS_RTNL_LINK(DRV_NAME);
2033MODULE_VERSION(DRV_VERSION);
v4.6
 
  1/*
  2 * vrf.c: device driver to encapsulate a VRF space
  3 *
  4 * Copyright (c) 2015 Cumulus Networks. All rights reserved.
  5 * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
  6 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
  7 *
  8 * Based on dummy, team and ipvlan drivers
  9 *
 10 * This program is free software; you can redistribute it and/or modify
 11 * it under the terms of the GNU General Public License as published by
 12 * the Free Software Foundation; either version 2 of the License, or
 13 * (at your option) any later version.
 14 */
 15
 
 16#include <linux/module.h>
 17#include <linux/kernel.h>
 18#include <linux/netdevice.h>
 19#include <linux/etherdevice.h>
 20#include <linux/ip.h>
 21#include <linux/init.h>
 22#include <linux/moduleparam.h>
 23#include <linux/netfilter.h>
 24#include <linux/rtnetlink.h>
 25#include <net/rtnetlink.h>
 26#include <linux/u64_stats_sync.h>
 27#include <linux/hashtable.h>
 
 28
 29#include <linux/inetdevice.h>
 30#include <net/arp.h>
 31#include <net/ip.h>
 32#include <net/ip_fib.h>
 33#include <net/ip6_fib.h>
 34#include <net/ip6_route.h>
 35#include <net/route.h>
 36#include <net/addrconf.h>
 37#include <net/l3mdev.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 38
 39#define RT_FL_TOS(oldflp4) \
 40	((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
 41
 42#define DRV_NAME	"vrf"
 43#define DRV_VERSION	"1.0"
 
 
 44
 45#define vrf_master_get_rcu(dev) \
 46	((struct net_device *)rcu_dereference(dev->rx_handler_data))
 
 47
 48struct net_vrf {
 49	struct rtable           *rth;
 50	struct rt6_info		*rt6;
 
 
 
 51	u32                     tb_id;
 
 
 
 52};
 53
 54struct pcpu_dstats {
 55	u64			tx_pkts;
 56	u64			tx_bytes;
 57	u64			tx_drps;
 58	u64			rx_pkts;
 59	u64			rx_bytes;
 60	struct u64_stats_sync	syncp;
 61};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 62
 63/* neighbor handling is done with actual device; do not want
 64 * to flip skb->dev for those ndisc packets. This really fails
 65 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
 66 * a start.
 67 */
 68#if IS_ENABLED(CONFIG_IPV6)
 69static bool check_ipv6_frame(const struct sk_buff *skb)
 70{
 71	const struct ipv6hdr *ipv6h;
 72	struct ipv6hdr _ipv6h;
 73	bool rc = true;
 74
 75	ipv6h = skb_header_pointer(skb, 0, sizeof(_ipv6h), &_ipv6h);
 76	if (!ipv6h)
 77		goto out;
 
 78
 79	if (ipv6h->nexthdr == NEXTHDR_ICMP) {
 80		const struct icmp6hdr *icmph;
 81		struct icmp6hdr _icmph;
 
 82
 83		icmph = skb_header_pointer(skb, sizeof(_ipv6h),
 84					   sizeof(_icmph), &_icmph);
 85		if (!icmph)
 86			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 87
 88		switch (icmph->icmp6_type) {
 89		case NDISC_ROUTER_SOLICITATION:
 90		case NDISC_ROUTER_ADVERTISEMENT:
 91		case NDISC_NEIGHBOUR_SOLICITATION:
 92		case NDISC_NEIGHBOUR_ADVERTISEMENT:
 93		case NDISC_REDIRECT:
 94			rc = false;
 95			break;
 96		}
 97	}
 98
 99out:
100	return rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
101}
102#else
103static bool check_ipv6_frame(const struct sk_buff *skb)
 
104{
105	return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
106}
107#endif
108
109static bool is_ip_rx_frame(struct sk_buff *skb)
 
110{
111	switch (skb->protocol) {
112	case htons(ETH_P_IP):
113		return true;
114	case htons(ETH_P_IPV6):
115		return check_ipv6_frame(skb);
 
 
 
 
 
 
 
 
 
 
116	}
117	return false;
 
 
 
 
 
 
118}
119
120static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
 
 
 
121{
122	vrf_dev->stats.tx_errors++;
123	kfree_skb(skb);
 
 
 
 
 
 
 
 
124}
125
126/* note: already called with rcu_read_lock */
127static rx_handler_result_t vrf_handle_frame(struct sk_buff **pskb)
 
 
 
128{
129	struct sk_buff *skb = *pskb;
 
 
 
 
 
 
 
 
 
 
 
130
131	if (is_ip_rx_frame(skb)) {
132		struct net_device *dev = vrf_master_get_rcu(skb->dev);
 
133		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
134
135		u64_stats_update_begin(&dstats->syncp);
136		dstats->rx_pkts++;
137		dstats->rx_bytes += skb->len;
138		u64_stats_update_end(&dstats->syncp);
 
139
140		skb->dev = dev;
 
141
142		return RX_HANDLER_ANOTHER;
143	}
144	return RX_HANDLER_PASS;
 
145}
146
147static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
148						 struct rtnl_link_stats64 *stats)
149{
150	int i;
151
152	for_each_possible_cpu(i) {
153		const struct pcpu_dstats *dstats;
154		u64 tbytes, tpkts, tdrops, rbytes, rpkts;
155		unsigned int start;
156
157		dstats = per_cpu_ptr(dev->dstats, i);
158		do {
159			start = u64_stats_fetch_begin_irq(&dstats->syncp);
160			tbytes = dstats->tx_bytes;
161			tpkts = dstats->tx_pkts;
162			tdrops = dstats->tx_drps;
163			rbytes = dstats->rx_bytes;
164			rpkts = dstats->rx_pkts;
165		} while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
166		stats->tx_bytes += tbytes;
167		stats->tx_packets += tpkts;
168		stats->tx_dropped += tdrops;
169		stats->rx_bytes += rbytes;
170		stats->rx_packets += rpkts;
171	}
172	return stats;
173}
174
175#if IS_ENABLED(CONFIG_IPV6)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
176static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
177					   struct net_device *dev)
178{
179	const struct ipv6hdr *iph = ipv6_hdr(skb);
180	struct net *net = dev_net(skb->dev);
181	struct flowi6 fl6 = {
182		/* needed to match OIF rule */
183		.flowi6_oif = dev->ifindex,
184		.flowi6_iif = LOOPBACK_IFINDEX,
185		.daddr = iph->daddr,
186		.saddr = iph->saddr,
187		.flowlabel = ip6_flowinfo(iph),
188		.flowi6_mark = skb->mark,
189		.flowi6_proto = iph->nexthdr,
190		.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF,
191	};
192	int ret = NET_XMIT_DROP;
193	struct dst_entry *dst;
194	struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
195
196	dst = ip6_route_output(net, NULL, &fl6);
197	if (dst == dst_null)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
198		goto err;
199
200	skb_dst_drop(skb);
 
 
 
 
 
 
 
201	skb_dst_set(skb, dst);
202
203	ret = ip6_local_out(net, skb->sk, skb);
 
 
 
 
204	if (unlikely(net_xmit_eval(ret)))
205		dev->stats.tx_errors++;
206	else
207		ret = NET_XMIT_SUCCESS;
208
209	return ret;
210err:
211	vrf_tx_error(dev, skb);
212	return NET_XMIT_DROP;
213}
214#else
215static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
216					   struct net_device *dev)
217{
218	vrf_tx_error(dev, skb);
219	return NET_XMIT_DROP;
220}
221#endif
222
223static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4,
224			    struct net_device *vrf_dev)
225{
226	struct rtable *rt;
227	int err = 1;
228
229	rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL);
230	if (IS_ERR(rt))
231		goto out;
 
 
 
232
233	/* TO-DO: what about broadcast ? */
234	if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
235		ip_rt_put(rt);
236		goto out;
237	}
238
239	skb_dst_drop(skb);
240	skb_dst_set(skb, &rt->dst);
241	err = 0;
242out:
243	return err;
244}
245
246static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
247					   struct net_device *vrf_dev)
248{
249	struct iphdr *ip4h = ip_hdr(skb);
250	int ret = NET_XMIT_DROP;
251	struct flowi4 fl4 = {
252		/* needed to match OIF rule */
253		.flowi4_oif = vrf_dev->ifindex,
254		.flowi4_iif = LOOPBACK_IFINDEX,
255		.flowi4_tos = RT_TOS(ip4h->tos),
256		.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_L3MDEV_SRC |
257				FLOWI_FLAG_SKIP_NH_OIF,
258		.daddr = ip4h->daddr,
259	};
 
 
 
 
 
 
 
 
 
260
261	if (vrf_send_v4_prep(skb, &fl4, vrf_dev))
 
262		goto err;
263
 
 
 
 
 
 
 
 
 
 
 
 
 
264	if (!ip4h->saddr) {
265		ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
266					       RT_SCOPE_LINK);
267	}
268
269	ret = ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 
270	if (unlikely(net_xmit_eval(ret)))
271		vrf_dev->stats.tx_errors++;
272	else
273		ret = NET_XMIT_SUCCESS;
274
275out:
276	return ret;
277err:
278	vrf_tx_error(vrf_dev, skb);
279	goto out;
280}
281
282static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
283{
284	/* strip the ethernet header added for pass through VRF device */
285	__skb_pull(skb, skb_network_offset(skb));
286
287	switch (skb->protocol) {
288	case htons(ETH_P_IP):
289		return vrf_process_v4_outbound(skb, dev);
290	case htons(ETH_P_IPV6):
291		return vrf_process_v6_outbound(skb, dev);
292	default:
293		vrf_tx_error(dev, skb);
294		return NET_XMIT_DROP;
295	}
296}
297
298static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
299{
 
 
 
300	netdev_tx_t ret = is_ip_tx_frame(skb, dev);
301
 
302	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
303		struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
304
305		u64_stats_update_begin(&dstats->syncp);
306		dstats->tx_pkts++;
307		dstats->tx_bytes += skb->len;
308		u64_stats_update_end(&dstats->syncp);
309	} else {
310		this_cpu_inc(dev->dstats->tx_drps);
311	}
 
312
313	return ret;
314}
315
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
316#if IS_ENABLED(CONFIG_IPV6)
317/* modelled after ip6_finish_output2 */
318static int vrf_finish_output6(struct net *net, struct sock *sk,
319			      struct sk_buff *skb)
320{
321	struct dst_entry *dst = skb_dst(skb);
322	struct net_device *dev = dst->dev;
 
323	struct neighbour *neigh;
324	struct in6_addr *nexthop;
325	int ret;
326
 
 
327	skb->protocol = htons(ETH_P_IPV6);
328	skb->dev = dev;
329
330	rcu_read_lock_bh();
331	nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
332	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
333	if (unlikely(!neigh))
334		neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
335	if (!IS_ERR(neigh)) {
336		ret = dst_neigh_output(dst, neigh, skb);
337		rcu_read_unlock_bh();
 
338		return ret;
339	}
340	rcu_read_unlock_bh();
341
342	IP6_INC_STATS(dev_net(dst->dev),
343		      ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
344	kfree_skb(skb);
345	return -EINVAL;
346}
347
348/* modelled after ip6_output */
349static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
350{
351	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
352			    net, sk, skb, NULL, skb_dst(skb)->dev,
353			    vrf_finish_output6,
354			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
355}
356
357static void vrf_rt6_release(struct net_vrf *vrf)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
358{
359	dst_release(&vrf->rt6->dst);
360	vrf->rt6 = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
361}
362
363static int vrf_rt6_create(struct net_device *dev)
364{
 
365	struct net_vrf *vrf = netdev_priv(dev);
366	struct net *net = dev_net(dev);
367	struct rt6_info *rt6;
368	int rc = -ENOMEM;
369
370	rt6 = ip6_dst_alloc(net, dev,
371			    DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE);
 
 
 
 
 
 
 
 
372	if (!rt6)
373		goto out;
374
375	rt6->dst.output	= vrf_output6;
376	rt6->rt6i_table = fib6_get_table(net, vrf->tb_id);
377	dst_hold(&rt6->dst);
378	vrf->rt6 = rt6;
379	rc = 0;
380out:
381	return rc;
382}
383#else
384static void vrf_rt6_release(struct net_vrf *vrf)
 
 
 
 
 
 
 
385{
386}
387
388static int vrf_rt6_create(struct net_device *dev)
389{
390	return 0;
391}
392#endif
393
394/* modelled after ip_finish_output2 */
395static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
396{
397	struct dst_entry *dst = skb_dst(skb);
398	struct rtable *rt = (struct rtable *)dst;
399	struct net_device *dev = dst->dev;
400	unsigned int hh_len = LL_RESERVED_SPACE(dev);
401	struct neighbour *neigh;
402	u32 nexthop;
403	int ret = -EINVAL;
 
404
405	/* Be paranoid, rather than too clever. */
406	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
407		struct sk_buff *skb2;
408
409		skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
410		if (!skb2) {
411			ret = -ENOMEM;
412			goto err;
413		}
414		if (skb->sk)
415			skb_set_owner_w(skb2, skb->sk);
416
417		consume_skb(skb);
418		skb = skb2;
419	}
420
421	rcu_read_lock_bh();
 
 
422
423	nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
424	neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
425	if (unlikely(!neigh))
426		neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
427	if (!IS_ERR(neigh))
428		ret = dst_neigh_output(dst, neigh, skb);
429
430	rcu_read_unlock_bh();
431err:
432	if (unlikely(ret < 0))
433		vrf_tx_error(skb->dev, skb);
434	return ret;
435}
436
437static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
438{
439	struct net_device *dev = skb_dst(skb)->dev;
440
441	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
442
443	skb->dev = dev;
444	skb->protocol = htons(ETH_P_IP);
445
446	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
447			    net, sk, skb, NULL, dev,
448			    vrf_finish_output,
449			    !(IPCB(skb)->flags & IPSKB_REROUTED));
450}
451
452static void vrf_rtable_release(struct net_vrf *vrf)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
453{
454	struct dst_entry *dst = (struct dst_entry *)vrf->rth;
 
 
 
 
 
455
456	dst_release(dst);
457	vrf->rth = NULL;
458}
459
460static struct rtable *vrf_rtable_create(struct net_device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
461{
462	struct net_vrf *vrf = netdev_priv(dev);
463	struct rtable *rth;
464
465	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
466	if (rth) {
467		rth->dst.output	= vrf_output;
468		rth->rt_table_id = vrf->tb_id;
469	}
 
 
 
 
 
 
470
471	return rth;
472}
473
474/**************************** device handling ********************/
475
476/* cycle interface to flush neighbor cache and move routes across tables */
477static void cycle_netdev(struct net_device *dev)
 
478{
479	unsigned int flags = dev->flags;
480	int ret;
481
482	if (!netif_running(dev))
483		return;
484
485	ret = dev_change_flags(dev, flags & ~IFF_UP);
486	if (ret >= 0)
487		ret = dev_change_flags(dev, flags);
488
489	if (ret < 0) {
490		netdev_err(dev,
491			   "Failed to cycle device %s; route tables might be wrong!\n",
492			   dev->name);
493	}
494}
495
496static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 
497{
498	int ret;
499
500	/* register the packet handler for slave ports */
501	ret = netdev_rx_handler_register(port_dev, vrf_handle_frame, dev);
502	if (ret) {
503		netdev_err(port_dev,
504			   "Device %s failed to register rx_handler\n",
505			   port_dev->name);
506		goto out_fail;
507	}
508
509	ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL);
 
510	if (ret < 0)
511		goto out_unregister;
512
513	port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
514	cycle_netdev(port_dev);
515
516	return 0;
517
518out_unregister:
519	netdev_rx_handler_unregister(port_dev);
520out_fail:
521	return ret;
522}
523
524static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 
525{
526	if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
 
 
 
 
 
 
527		return -EINVAL;
528
529	return do_vrf_add_slave(dev, port_dev);
530}
531
532/* inverse of do_vrf_add_slave */
533static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
534{
535	netdev_upper_dev_unlink(port_dev, dev);
536	port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
537
538	netdev_rx_handler_unregister(port_dev);
539
540	cycle_netdev(port_dev);
541
542	return 0;
543}
544
545static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
546{
547	return do_vrf_del_slave(dev, port_dev);
548}
549
550static void vrf_dev_uninit(struct net_device *dev)
551{
552	struct net_vrf *vrf = netdev_priv(dev);
553	struct net_device *port_dev;
554	struct list_head *iter;
555
556	vrf_rtable_release(vrf);
557	vrf_rt6_release(vrf);
558
559	netdev_for_each_lower_dev(dev, port_dev, iter)
560		vrf_del_slave(dev, port_dev);
561
562	free_percpu(dev->dstats);
563	dev->dstats = NULL;
564}
565
566static int vrf_dev_init(struct net_device *dev)
567{
568	struct net_vrf *vrf = netdev_priv(dev);
569
570	dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
571	if (!dev->dstats)
572		goto out_nomem;
573
574	/* create the default dst which points back to us */
575	vrf->rth = vrf_rtable_create(dev);
576	if (!vrf->rth)
577		goto out_stats;
578
579	if (vrf_rt6_create(dev) != 0)
580		goto out_rth;
581
582	dev->flags = IFF_MASTER | IFF_NOARP;
583
 
 
 
584	return 0;
585
586out_rth:
587	vrf_rtable_release(vrf);
588out_stats:
589	free_percpu(dev->dstats);
590	dev->dstats = NULL;
591out_nomem:
592	return -ENOMEM;
593}
594
595static const struct net_device_ops vrf_netdev_ops = {
596	.ndo_init		= vrf_dev_init,
597	.ndo_uninit		= vrf_dev_uninit,
598	.ndo_start_xmit		= vrf_xmit,
599	.ndo_get_stats64	= vrf_get_stats64,
600	.ndo_add_slave		= vrf_add_slave,
601	.ndo_del_slave		= vrf_del_slave,
602};
603
604static u32 vrf_fib_table(const struct net_device *dev)
605{
606	struct net_vrf *vrf = netdev_priv(dev);
607
608	return vrf->tb_id;
609}
610
611static struct rtable *vrf_get_rtable(const struct net_device *dev,
612				     const struct flowi4 *fl4)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
613{
614	struct rtable *rth = NULL;
 
615
616	if (!(fl4->flowi4_flags & FLOWI_FLAG_L3MDEV_SRC)) {
617		struct net_vrf *vrf = netdev_priv(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
618
619		rth = vrf->rth;
620		dst_hold(&rth->dst);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
621	}
622
623	return rth;
 
624}
625
626/* called under rcu_read_lock */
627static int vrf_get_saddr(struct net_device *dev, struct flowi4 *fl4)
 
 
 
 
628{
629	struct fib_result res = { .tclassid = 0 };
630	struct net *net = dev_net(dev);
631	u32 orig_tos = fl4->flowi4_tos;
632	u8 flags = fl4->flowi4_flags;
633	u8 scope = fl4->flowi4_scope;
634	u8 tos = RT_FL_TOS(fl4);
635	int rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
636
637	if (unlikely(!fl4->daddr))
638		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
639
640	fl4->flowi4_flags |= FLOWI_FLAG_SKIP_NH_OIF;
641	fl4->flowi4_iif = LOOPBACK_IFINDEX;
642	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
643	fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
644			     RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
645
646	rc = fib_lookup(net, fl4, &res, 0);
647	if (!rc) {
648		if (res.type == RTN_LOCAL)
649			fl4->saddr = res.fi->fib_prefsrc ? : fl4->daddr;
650		else
651			fib_select_path(net, &res, fl4, -1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
652	}
653
654	fl4->flowi4_flags = flags;
655	fl4->flowi4_tos = orig_tos;
656	fl4->flowi4_scope = scope;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
657
658	return rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
659}
660
661#if IS_ENABLED(CONFIG_IPV6)
662static struct dst_entry *vrf_get_rt6_dst(const struct net_device *dev,
663					 const struct flowi6 *fl6)
 
 
 
 
 
664{
665	struct rt6_info *rt = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
666
667	if (!(fl6->flowi6_flags & FLOWI_FLAG_L3MDEV_SRC)) {
668		struct net_vrf *vrf = netdev_priv(dev);
669
670		rt = vrf->rt6;
671		dst_hold(&rt->dst);
672	}
673
674	return (struct dst_entry *)rt;
675}
676#endif
677
678static const struct l3mdev_ops vrf_l3mdev_ops = {
679	.l3mdev_fib_table	= vrf_fib_table,
680	.l3mdev_get_rtable	= vrf_get_rtable,
681	.l3mdev_get_saddr	= vrf_get_saddr,
682#if IS_ENABLED(CONFIG_IPV6)
683	.l3mdev_get_rt6_dst	= vrf_get_rt6_dst,
684#endif
685};
686
687static void vrf_get_drvinfo(struct net_device *dev,
688			    struct ethtool_drvinfo *info)
689{
690	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
691	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
692}
693
694static const struct ethtool_ops vrf_ethtool_ops = {
695	.get_drvinfo	= vrf_get_drvinfo,
696};
697
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
698static void vrf_setup(struct net_device *dev)
699{
700	ether_setup(dev);
701
702	/* Initialize the device structure. */
703	dev->netdev_ops = &vrf_netdev_ops;
704	dev->l3mdev_ops = &vrf_l3mdev_ops;
705	dev->ethtool_ops = &vrf_ethtool_ops;
706	dev->destructor = free_netdev;
707
708	/* Fill in device structure with ethernet-generic values. */
709	eth_hw_addr_random(dev);
710
711	/* don't acquire vrf device's netif_tx_lock when transmitting */
712	dev->features |= NETIF_F_LLTX;
713
714	/* don't allow vrf devices to change network namespaces. */
715	dev->features |= NETIF_F_NETNS_LOCAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
716}
717
718static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
 
719{
720	if (tb[IFLA_ADDRESS]) {
721		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 
722			return -EINVAL;
723		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 
 
724			return -EADDRNOTAVAIL;
 
725	}
726	return 0;
727}
728
729static void vrf_dellink(struct net_device *dev, struct list_head *head)
730{
 
 
 
 
 
 
 
 
731	unregister_netdevice_queue(dev, head);
732}
733
734static int vrf_newlink(struct net *src_net, struct net_device *dev,
735		       struct nlattr *tb[], struct nlattr *data[])
 
736{
737	struct net_vrf *vrf = netdev_priv(dev);
 
 
 
 
738
739	if (!data || !data[IFLA_VRF_TABLE])
 
740		return -EINVAL;
 
741
742	vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
 
 
 
 
 
743
744	dev->priv_flags |= IFF_L3MDEV_MASTER;
745
746	return register_netdevice(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
747}
748
749static size_t vrf_nl_getsize(const struct net_device *dev)
750{
751	return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
752}
753
754static int vrf_fillinfo(struct sk_buff *skb,
755			const struct net_device *dev)
756{
757	struct net_vrf *vrf = netdev_priv(dev);
758
759	return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
760}
761
762static size_t vrf_get_slave_size(const struct net_device *bond_dev,
763				 const struct net_device *slave_dev)
764{
765	return nla_total_size(sizeof(u32));  /* IFLA_VRF_PORT_TABLE */
766}
767
768static int vrf_fill_slave_info(struct sk_buff *skb,
769			       const struct net_device *vrf_dev,
770			       const struct net_device *slave_dev)
771{
772	struct net_vrf *vrf = netdev_priv(vrf_dev);
773
774	if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
775		return -EMSGSIZE;
776
777	return 0;
778}
779
780static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
781	[IFLA_VRF_TABLE] = { .type = NLA_U32 },
782};
783
784static struct rtnl_link_ops vrf_link_ops __read_mostly = {
785	.kind		= DRV_NAME,
786	.priv_size	= sizeof(struct net_vrf),
787
788	.get_size	= vrf_nl_getsize,
789	.policy		= vrf_nl_policy,
790	.validate	= vrf_validate,
791	.fill_info	= vrf_fillinfo,
792
793	.get_slave_size  = vrf_get_slave_size,
794	.fill_slave_info = vrf_fill_slave_info,
795
796	.newlink	= vrf_newlink,
797	.dellink	= vrf_dellink,
798	.setup		= vrf_setup,
799	.maxtype	= IFLA_VRF_MAX,
800};
801
802static int vrf_device_event(struct notifier_block *unused,
803			    unsigned long event, void *ptr)
804{
805	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
806
807	/* only care about unregister events to drop slave references */
808	if (event == NETDEV_UNREGISTER) {
809		struct net_device *vrf_dev;
810
811		if (!netif_is_l3_slave(dev))
812			goto out;
813
814		vrf_dev = netdev_master_upper_dev_get(dev);
815		vrf_del_slave(vrf_dev, dev);
816	}
817out:
818	return NOTIFY_DONE;
819}
820
821static struct notifier_block vrf_notifier_block __read_mostly = {
822	.notifier_call = vrf_device_event,
823};
824
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
825static int __init vrf_init_module(void)
826{
827	int rc;
828
829	register_netdevice_notifier(&vrf_notifier_block);
830
 
 
 
 
 
 
 
 
 
831	rc = rtnl_link_register(&vrf_link_ops);
832	if (rc < 0)
833		goto error;
834
835	return 0;
 
 
 
 
 
 
 
836
837error:
838	unregister_netdevice_notifier(&vrf_notifier_block);
839	return rc;
840}
841
842module_init(vrf_init_module);
843MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
844MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
845MODULE_LICENSE("GPL");
846MODULE_ALIAS_RTNL_LINK(DRV_NAME);
847MODULE_VERSION(DRV_VERSION);