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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2007-2017 Nicira, Inc.
   4 */
   5
   6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7
   8#include <linux/skbuff.h>
   9#include <linux/in.h>
  10#include <linux/ip.h>
  11#include <linux/openvswitch.h>
  12#include <linux/sctp.h>
  13#include <linux/tcp.h>
  14#include <linux/udp.h>
  15#include <linux/in6.h>
  16#include <linux/if_arp.h>
  17#include <linux/if_vlan.h>
  18
  19#include <net/dst.h>
  20#include <net/ip.h>
  21#include <net/ipv6.h>
  22#include <net/ip6_fib.h>
  23#include <net/checksum.h>
  24#include <net/dsfield.h>
  25#include <net/mpls.h>
  26#include <net/sctp/checksum.h>
  27
  28#include "datapath.h"
  29#include "flow.h"
  30#include "conntrack.h"
  31#include "vport.h"
  32#include "flow_netlink.h"
  33#include "openvswitch_trace.h"
  34
  35struct deferred_action {
  36	struct sk_buff *skb;
  37	const struct nlattr *actions;
  38	int actions_len;
  39
  40	/* Store pkt_key clone when creating deferred action. */
  41	struct sw_flow_key pkt_key;
  42};
  43
  44#define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
  45struct ovs_frag_data {
  46	unsigned long dst;
  47	struct vport *vport;
  48	struct ovs_skb_cb cb;
  49	__be16 inner_protocol;
  50	u16 network_offset;	/* valid only for MPLS */
  51	u16 vlan_tci;
  52	__be16 vlan_proto;
  53	unsigned int l2_len;
  54	u8 mac_proto;
  55	u8 l2_data[MAX_L2_LEN];
  56};
  57
  58static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
  59
  60#define DEFERRED_ACTION_FIFO_SIZE 10
  61#define OVS_RECURSION_LIMIT 5
  62#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
  63struct action_fifo {
  64	int head;
  65	int tail;
  66	/* Deferred action fifo queue storage. */
  67	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
  68};
  69
  70struct action_flow_keys {
  71	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
  72};
  73
  74static struct action_fifo __percpu *action_fifos;
  75static struct action_flow_keys __percpu *flow_keys;
  76static DEFINE_PER_CPU(int, exec_actions_level);
  77
  78/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
  79 * space. Return NULL if out of key spaces.
  80 */
  81static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
  82{
  83	struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
  84	int level = this_cpu_read(exec_actions_level);
  85	struct sw_flow_key *key = NULL;
  86
  87	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
  88		key = &keys->key[level - 1];
  89		*key = *key_;
  90	}
  91
  92	return key;
  93}
  94
  95static void action_fifo_init(struct action_fifo *fifo)
  96{
  97	fifo->head = 0;
  98	fifo->tail = 0;
  99}
 100
 101static bool action_fifo_is_empty(const struct action_fifo *fifo)
 102{
 103	return (fifo->head == fifo->tail);
 104}
 105
 106static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
 107{
 108	if (action_fifo_is_empty(fifo))
 109		return NULL;
 110
 111	return &fifo->fifo[fifo->tail++];
 112}
 113
 114static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
 115{
 116	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
 117		return NULL;
 118
 119	return &fifo->fifo[fifo->head++];
 120}
 121
 122/* Return true if fifo is not full */
 123static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
 124				    const struct sw_flow_key *key,
 125				    const struct nlattr *actions,
 126				    const int actions_len)
 127{
 128	struct action_fifo *fifo;
 129	struct deferred_action *da;
 130
 131	fifo = this_cpu_ptr(action_fifos);
 132	da = action_fifo_put(fifo);
 133	if (da) {
 134		da->skb = skb;
 135		da->actions = actions;
 136		da->actions_len = actions_len;
 137		da->pkt_key = *key;
 138	}
 139
 140	return da;
 141}
 142
 143static void invalidate_flow_key(struct sw_flow_key *key)
 144{
 145	key->mac_proto |= SW_FLOW_KEY_INVALID;
 146}
 147
 148static bool is_flow_key_valid(const struct sw_flow_key *key)
 149{
 150	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
 151}
 152
 153static int clone_execute(struct datapath *dp, struct sk_buff *skb,
 154			 struct sw_flow_key *key,
 155			 u32 recirc_id,
 156			 const struct nlattr *actions, int len,
 157			 bool last, bool clone_flow_key);
 158
 159static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 160			      struct sw_flow_key *key,
 161			      const struct nlattr *attr, int len);
 162
 163static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 164		     __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len)
 165{
 166	int err;
 167
 168	err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len);
 169	if (err)
 170		return err;
 171
 172	if (!mac_len)
 173		key->mac_proto = MAC_PROTO_NONE;
 174
 175	invalidate_flow_key(key);
 176	return 0;
 177}
 178
 179static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 180		    const __be16 ethertype)
 181{
 182	int err;
 183
 184	err = skb_mpls_pop(skb, ethertype, skb->mac_len,
 185			   ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET);
 186	if (err)
 187		return err;
 188
 189	if (ethertype == htons(ETH_P_TEB))
 190		key->mac_proto = MAC_PROTO_ETHERNET;
 191
 192	invalidate_flow_key(key);
 193	return 0;
 194}
 195
 196static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 197		    const __be32 *mpls_lse, const __be32 *mask)
 198{
 199	struct mpls_shim_hdr *stack;
 200	__be32 lse;
 201	int err;
 202
 203	if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN))
 204		return -ENOMEM;
 205
 206	stack = mpls_hdr(skb);
 207	lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
 208	err = skb_mpls_update_lse(skb, lse);
 209	if (err)
 210		return err;
 211
 212	flow_key->mpls.lse[0] = lse;
 213	return 0;
 214}
 215
 216static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 217{
 218	int err;
 219
 220	err = skb_vlan_pop(skb);
 221	if (skb_vlan_tag_present(skb)) {
 222		invalidate_flow_key(key);
 223	} else {
 224		key->eth.vlan.tci = 0;
 225		key->eth.vlan.tpid = 0;
 226	}
 227	return err;
 228}
 229
 230static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 231		     const struct ovs_action_push_vlan *vlan)
 232{
 233	if (skb_vlan_tag_present(skb)) {
 234		invalidate_flow_key(key);
 235	} else {
 236		key->eth.vlan.tci = vlan->vlan_tci;
 237		key->eth.vlan.tpid = vlan->vlan_tpid;
 238	}
 239	return skb_vlan_push(skb, vlan->vlan_tpid,
 240			     ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
 241}
 242
 243/* 'src' is already properly masked. */
 244static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 245{
 246	u16 *dst = (u16 *)dst_;
 247	const u16 *src = (const u16 *)src_;
 248	const u16 *mask = (const u16 *)mask_;
 249
 250	OVS_SET_MASKED(dst[0], src[0], mask[0]);
 251	OVS_SET_MASKED(dst[1], src[1], mask[1]);
 252	OVS_SET_MASKED(dst[2], src[2], mask[2]);
 253}
 254
 255static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 256			const struct ovs_key_ethernet *key,
 257			const struct ovs_key_ethernet *mask)
 258{
 259	int err;
 260
 261	err = skb_ensure_writable(skb, ETH_HLEN);
 262	if (unlikely(err))
 263		return err;
 264
 265	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 266
 267	ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 268			       mask->eth_src);
 269	ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 270			       mask->eth_dst);
 271
 272	skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 273
 274	ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 275	ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 276	return 0;
 277}
 278
 279/* pop_eth does not support VLAN packets as this action is never called
 280 * for them.
 281 */
 282static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
 283{
 284	int err;
 285
 286	err = skb_eth_pop(skb);
 287	if (err)
 288		return err;
 289
 290	/* safe right before invalidate_flow_key */
 291	key->mac_proto = MAC_PROTO_NONE;
 292	invalidate_flow_key(key);
 293	return 0;
 294}
 295
 296static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
 297		    const struct ovs_action_push_eth *ethh)
 298{
 299	int err;
 300
 301	err = skb_eth_push(skb, ethh->addresses.eth_dst,
 302			   ethh->addresses.eth_src);
 303	if (err)
 304		return err;
 305
 306	/* safe right before invalidate_flow_key */
 307	key->mac_proto = MAC_PROTO_ETHERNET;
 308	invalidate_flow_key(key);
 309	return 0;
 310}
 311
 312static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key,
 313		    const struct nshhdr *nh)
 314{
 315	int err;
 316
 317	err = nsh_push(skb, nh);
 318	if (err)
 319		return err;
 320
 321	/* safe right before invalidate_flow_key */
 322	key->mac_proto = MAC_PROTO_NONE;
 323	invalidate_flow_key(key);
 324	return 0;
 325}
 326
 327static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 328{
 329	int err;
 330
 331	err = nsh_pop(skb);
 332	if (err)
 333		return err;
 334
 335	/* safe right before invalidate_flow_key */
 336	if (skb->protocol == htons(ETH_P_TEB))
 337		key->mac_proto = MAC_PROTO_ETHERNET;
 338	else
 339		key->mac_proto = MAC_PROTO_NONE;
 340	invalidate_flow_key(key);
 341	return 0;
 342}
 343
 344static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
 345				  __be32 addr, __be32 new_addr)
 346{
 347	int transport_len = skb->len - skb_transport_offset(skb);
 348
 349	if (nh->frag_off & htons(IP_OFFSET))
 350		return;
 351
 352	if (nh->protocol == IPPROTO_TCP) {
 353		if (likely(transport_len >= sizeof(struct tcphdr)))
 354			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 355						 addr, new_addr, true);
 356	} else if (nh->protocol == IPPROTO_UDP) {
 357		if (likely(transport_len >= sizeof(struct udphdr))) {
 358			struct udphdr *uh = udp_hdr(skb);
 359
 360			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 361				inet_proto_csum_replace4(&uh->check, skb,
 362							 addr, new_addr, true);
 363				if (!uh->check)
 364					uh->check = CSUM_MANGLED_0;
 365			}
 366		}
 367	}
 368}
 369
 370static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 371			__be32 *addr, __be32 new_addr)
 372{
 373	update_ip_l4_checksum(skb, nh, *addr, new_addr);
 374	csum_replace4(&nh->check, *addr, new_addr);
 375	skb_clear_hash(skb);
 
 376	*addr = new_addr;
 377}
 378
 379static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 380				 __be32 addr[4], const __be32 new_addr[4])
 381{
 382	int transport_len = skb->len - skb_transport_offset(skb);
 383
 384	if (l4_proto == NEXTHDR_TCP) {
 385		if (likely(transport_len >= sizeof(struct tcphdr)))
 386			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 387						  addr, new_addr, true);
 388	} else if (l4_proto == NEXTHDR_UDP) {
 389		if (likely(transport_len >= sizeof(struct udphdr))) {
 390			struct udphdr *uh = udp_hdr(skb);
 391
 392			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 393				inet_proto_csum_replace16(&uh->check, skb,
 394							  addr, new_addr, true);
 395				if (!uh->check)
 396					uh->check = CSUM_MANGLED_0;
 397			}
 398		}
 399	} else if (l4_proto == NEXTHDR_ICMP) {
 400		if (likely(transport_len >= sizeof(struct icmp6hdr)))
 401			inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 402						  skb, addr, new_addr, true);
 403	}
 404}
 405
 406static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 407			   const __be32 mask[4], __be32 masked[4])
 408{
 409	masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
 410	masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
 411	masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
 412	masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
 413}
 414
 415static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 416			  __be32 addr[4], const __be32 new_addr[4],
 417			  bool recalculate_csum)
 418{
 419	if (recalculate_csum)
 420		update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 421
 422	skb_clear_hash(skb);
 
 423	memcpy(addr, new_addr, sizeof(__be32[4]));
 424}
 425
 426static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
 427{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 428	/* Bits 21-24 are always unmasked, so this retains their values. */
 429	OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
 430	OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
 431	OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 432}
 433
 434static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 435		       u8 mask)
 436{
 437	new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
 438
 439	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 440	nh->ttl = new_ttl;
 441}
 442
 443static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 444		    const struct ovs_key_ipv4 *key,
 445		    const struct ovs_key_ipv4 *mask)
 446{
 447	struct iphdr *nh;
 448	__be32 new_addr;
 449	int err;
 450
 451	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 452				  sizeof(struct iphdr));
 453	if (unlikely(err))
 454		return err;
 455
 456	nh = ip_hdr(skb);
 457
 458	/* Setting an IP addresses is typically only a side effect of
 459	 * matching on them in the current userspace implementation, so it
 460	 * makes sense to check if the value actually changed.
 461	 */
 462	if (mask->ipv4_src) {
 463		new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 464
 465		if (unlikely(new_addr != nh->saddr)) {
 466			set_ip_addr(skb, nh, &nh->saddr, new_addr);
 467			flow_key->ipv4.addr.src = new_addr;
 468		}
 469	}
 470	if (mask->ipv4_dst) {
 471		new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 472
 473		if (unlikely(new_addr != nh->daddr)) {
 474			set_ip_addr(skb, nh, &nh->daddr, new_addr);
 475			flow_key->ipv4.addr.dst = new_addr;
 476		}
 477	}
 478	if (mask->ipv4_tos) {
 479		ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 480		flow_key->ip.tos = nh->tos;
 481	}
 482	if (mask->ipv4_ttl) {
 483		set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 484		flow_key->ip.ttl = nh->ttl;
 485	}
 486
 487	return 0;
 488}
 489
 490static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 491{
 492	return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 493}
 494
 495static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 496		    const struct ovs_key_ipv6 *key,
 497		    const struct ovs_key_ipv6 *mask)
 498{
 499	struct ipv6hdr *nh;
 500	int err;
 501
 502	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 503				  sizeof(struct ipv6hdr));
 504	if (unlikely(err))
 505		return err;
 506
 507	nh = ipv6_hdr(skb);
 508
 509	/* Setting an IP addresses is typically only a side effect of
 510	 * matching on them in the current userspace implementation, so it
 511	 * makes sense to check if the value actually changed.
 512	 */
 513	if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 514		__be32 *saddr = (__be32 *)&nh->saddr;
 515		__be32 masked[4];
 516
 517		mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 518
 519		if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 520			set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
 521				      true);
 522			memcpy(&flow_key->ipv6.addr.src, masked,
 523			       sizeof(flow_key->ipv6.addr.src));
 524		}
 525	}
 526	if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 527		unsigned int offset = 0;
 528		int flags = IP6_FH_F_SKIP_RH;
 529		bool recalc_csum = true;
 530		__be32 *daddr = (__be32 *)&nh->daddr;
 531		__be32 masked[4];
 532
 533		mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 534
 535		if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 536			if (ipv6_ext_hdr(nh->nexthdr))
 537				recalc_csum = (ipv6_find_hdr(skb, &offset,
 538							     NEXTHDR_ROUTING,
 539							     NULL, &flags)
 540					       != NEXTHDR_ROUTING);
 541
 542			set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
 543				      recalc_csum);
 544			memcpy(&flow_key->ipv6.addr.dst, masked,
 545			       sizeof(flow_key->ipv6.addr.dst));
 546		}
 547	}
 548	if (mask->ipv6_tclass) {
 549		ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
 550		flow_key->ip.tos = ipv6_get_dsfield(nh);
 551	}
 552	if (mask->ipv6_label) {
 553		set_ipv6_fl(nh, ntohl(key->ipv6_label),
 554			    ntohl(mask->ipv6_label));
 555		flow_key->ipv6.label =
 556		    *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 557	}
 558	if (mask->ipv6_hlimit) {
 559		OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
 560			       mask->ipv6_hlimit);
 561		flow_key->ip.ttl = nh->hop_limit;
 562	}
 563	return 0;
 564}
 565
 566static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
 567		   const struct nlattr *a)
 568{
 569	struct nshhdr *nh;
 570	size_t length;
 571	int err;
 572	u8 flags;
 573	u8 ttl;
 574	int i;
 575
 576	struct ovs_key_nsh key;
 577	struct ovs_key_nsh mask;
 578
 579	err = nsh_key_from_nlattr(a, &key, &mask);
 580	if (err)
 581		return err;
 582
 583	/* Make sure the NSH base header is there */
 584	if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
 585		return -ENOMEM;
 586
 587	nh = nsh_hdr(skb);
 588	length = nsh_hdr_len(nh);
 589
 590	/* Make sure the whole NSH header is there */
 591	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 592				       length);
 593	if (unlikely(err))
 594		return err;
 595
 596	nh = nsh_hdr(skb);
 597	skb_postpull_rcsum(skb, nh, length);
 598	flags = nsh_get_flags(nh);
 599	flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
 600	flow_key->nsh.base.flags = flags;
 601	ttl = nsh_get_ttl(nh);
 602	ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
 603	flow_key->nsh.base.ttl = ttl;
 604	nsh_set_flags_and_ttl(nh, flags, ttl);
 605	nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
 606				  mask.base.path_hdr);
 607	flow_key->nsh.base.path_hdr = nh->path_hdr;
 608	switch (nh->mdtype) {
 609	case NSH_M_TYPE1:
 610		for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
 611			nh->md1.context[i] =
 612			    OVS_MASKED(nh->md1.context[i], key.context[i],
 613				       mask.context[i]);
 614		}
 615		memcpy(flow_key->nsh.context, nh->md1.context,
 616		       sizeof(nh->md1.context));
 617		break;
 618	case NSH_M_TYPE2:
 619		memset(flow_key->nsh.context, 0,
 620		       sizeof(flow_key->nsh.context));
 621		break;
 622	default:
 623		return -EINVAL;
 624	}
 625	skb_postpush_rcsum(skb, nh, length);
 626	return 0;
 627}
 628
 629/* Must follow skb_ensure_writable() since that can move the skb data. */
 630static void set_tp_port(struct sk_buff *skb, __be16 *port,
 631			__be16 new_port, __sum16 *check)
 632{
 
 633	inet_proto_csum_replace2(check, skb, *port, new_port, false);
 634	*port = new_port;
 635}
 636
 637static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 638		   const struct ovs_key_udp *key,
 639		   const struct ovs_key_udp *mask)
 640{
 641	struct udphdr *uh;
 642	__be16 src, dst;
 643	int err;
 644
 645	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 646				  sizeof(struct udphdr));
 647	if (unlikely(err))
 648		return err;
 649
 650	uh = udp_hdr(skb);
 651	/* Either of the masks is non-zero, so do not bother checking them. */
 652	src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
 653	dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 654
 655	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 656		if (likely(src != uh->source)) {
 657			set_tp_port(skb, &uh->source, src, &uh->check);
 658			flow_key->tp.src = src;
 659		}
 660		if (likely(dst != uh->dest)) {
 661			set_tp_port(skb, &uh->dest, dst, &uh->check);
 662			flow_key->tp.dst = dst;
 663		}
 664
 665		if (unlikely(!uh->check))
 666			uh->check = CSUM_MANGLED_0;
 667	} else {
 668		uh->source = src;
 669		uh->dest = dst;
 670		flow_key->tp.src = src;
 671		flow_key->tp.dst = dst;
 
 672	}
 673
 674	skb_clear_hash(skb);
 675
 676	return 0;
 677}
 678
 679static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 680		   const struct ovs_key_tcp *key,
 681		   const struct ovs_key_tcp *mask)
 682{
 683	struct tcphdr *th;
 684	__be16 src, dst;
 685	int err;
 686
 687	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 688				  sizeof(struct tcphdr));
 689	if (unlikely(err))
 690		return err;
 691
 692	th = tcp_hdr(skb);
 693	src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
 694	if (likely(src != th->source)) {
 695		set_tp_port(skb, &th->source, src, &th->check);
 696		flow_key->tp.src = src;
 697	}
 698	dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 699	if (likely(dst != th->dest)) {
 700		set_tp_port(skb, &th->dest, dst, &th->check);
 701		flow_key->tp.dst = dst;
 702	}
 703	skb_clear_hash(skb);
 704
 705	return 0;
 706}
 707
 708static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 709		    const struct ovs_key_sctp *key,
 710		    const struct ovs_key_sctp *mask)
 711{
 712	unsigned int sctphoff = skb_transport_offset(skb);
 713	struct sctphdr *sh;
 714	__le32 old_correct_csum, new_csum, old_csum;
 715	int err;
 716
 717	err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 718	if (unlikely(err))
 719		return err;
 720
 721	sh = sctp_hdr(skb);
 722	old_csum = sh->checksum;
 723	old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 724
 725	sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
 726	sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 727
 728	new_csum = sctp_compute_cksum(skb, sctphoff);
 729
 730	/* Carry any checksum errors through. */
 731	sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 732
 733	skb_clear_hash(skb);
 
 
 734	flow_key->tp.src = sh->source;
 735	flow_key->tp.dst = sh->dest;
 736
 737	return 0;
 738}
 739
 740static int ovs_vport_output(struct net *net, struct sock *sk,
 741			    struct sk_buff *skb)
 742{
 743	struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
 744	struct vport *vport = data->vport;
 745
 746	if (skb_cow_head(skb, data->l2_len) < 0) {
 747		kfree_skb(skb);
 748		return -ENOMEM;
 749	}
 750
 751	__skb_dst_copy(skb, data->dst);
 752	*OVS_CB(skb) = data->cb;
 753	skb->inner_protocol = data->inner_protocol;
 754	if (data->vlan_tci & VLAN_CFI_MASK)
 755		__vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK);
 756	else
 757		__vlan_hwaccel_clear_tag(skb);
 758
 759	/* Reconstruct the MAC header.  */
 760	skb_push(skb, data->l2_len);
 761	memcpy(skb->data, &data->l2_data, data->l2_len);
 762	skb_postpush_rcsum(skb, skb->data, data->l2_len);
 763	skb_reset_mac_header(skb);
 764
 765	if (eth_p_mpls(skb->protocol)) {
 766		skb->inner_network_header = skb->network_header;
 767		skb_set_network_header(skb, data->network_offset);
 768		skb_reset_mac_len(skb);
 769	}
 770
 771	ovs_vport_send(vport, skb, data->mac_proto);
 772	return 0;
 773}
 774
 775static unsigned int
 776ovs_dst_get_mtu(const struct dst_entry *dst)
 777{
 778	return dst->dev->mtu;
 779}
 780
 781static struct dst_ops ovs_dst_ops = {
 782	.family = AF_UNSPEC,
 783	.mtu = ovs_dst_get_mtu,
 784};
 785
 786/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 787 * ovs_vport_output(), which is called once per fragmented packet.
 788 */
 789static void prepare_frag(struct vport *vport, struct sk_buff *skb,
 790			 u16 orig_network_offset, u8 mac_proto)
 791{
 792	unsigned int hlen = skb_network_offset(skb);
 793	struct ovs_frag_data *data;
 794
 795	data = this_cpu_ptr(&ovs_frag_data_storage);
 796	data->dst = skb->_skb_refdst;
 797	data->vport = vport;
 798	data->cb = *OVS_CB(skb);
 799	data->inner_protocol = skb->inner_protocol;
 800	data->network_offset = orig_network_offset;
 801	if (skb_vlan_tag_present(skb))
 802		data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
 803	else
 804		data->vlan_tci = 0;
 805	data->vlan_proto = skb->vlan_proto;
 806	data->mac_proto = mac_proto;
 807	data->l2_len = hlen;
 808	memcpy(&data->l2_data, skb->data, hlen);
 809
 810	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 811	skb_pull(skb, hlen);
 812}
 813
 814static void ovs_fragment(struct net *net, struct vport *vport,
 815			 struct sk_buff *skb, u16 mru,
 816			 struct sw_flow_key *key)
 817{
 818	u16 orig_network_offset = 0;
 819
 820	if (eth_p_mpls(skb->protocol)) {
 821		orig_network_offset = skb_network_offset(skb);
 822		skb->network_header = skb->inner_network_header;
 823	}
 824
 825	if (skb_network_offset(skb) > MAX_L2_LEN) {
 826		OVS_NLERR(1, "L2 header too long to fragment");
 827		goto err;
 828	}
 829
 830	if (key->eth.type == htons(ETH_P_IP)) {
 831		struct rtable ovs_rt = { 0 };
 832		unsigned long orig_dst;
 833
 834		prepare_frag(vport, skb, orig_network_offset,
 835			     ovs_key_mac_proto(key));
 836		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 837			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 838		ovs_rt.dst.dev = vport->dev;
 839
 840		orig_dst = skb->_skb_refdst;
 841		skb_dst_set_noref(skb, &ovs_rt.dst);
 842		IPCB(skb)->frag_max_size = mru;
 843
 844		ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
 845		refdst_drop(orig_dst);
 846	} else if (key->eth.type == htons(ETH_P_IPV6)) {
 847		unsigned long orig_dst;
 848		struct rt6_info ovs_rt;
 849
 850		prepare_frag(vport, skb, orig_network_offset,
 851			     ovs_key_mac_proto(key));
 852		memset(&ovs_rt, 0, sizeof(ovs_rt));
 853		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 854			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 855		ovs_rt.dst.dev = vport->dev;
 856
 857		orig_dst = skb->_skb_refdst;
 858		skb_dst_set_noref(skb, &ovs_rt.dst);
 859		IP6CB(skb)->frag_max_size = mru;
 860
 861		ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output);
 862		refdst_drop(orig_dst);
 863	} else {
 864		WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
 865			  ovs_vport_name(vport), ntohs(key->eth.type), mru,
 866			  vport->dev->mtu);
 867		goto err;
 868	}
 869
 870	return;
 871err:
 872	kfree_skb(skb);
 873}
 874
 875static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
 876		      struct sw_flow_key *key)
 877{
 878	struct vport *vport = ovs_vport_rcu(dp, out_port);
 879
 880	if (likely(vport)) {
 881		u16 mru = OVS_CB(skb)->mru;
 882		u32 cutlen = OVS_CB(skb)->cutlen;
 883
 884		if (unlikely(cutlen > 0)) {
 885			if (skb->len - cutlen > ovs_mac_header_len(key))
 886				pskb_trim(skb, skb->len - cutlen);
 887			else
 888				pskb_trim(skb, ovs_mac_header_len(key));
 889		}
 890
 891		if (likely(!mru ||
 892		           (skb->len <= mru + vport->dev->hard_header_len))) {
 893			ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
 894		} else if (mru <= vport->dev->mtu) {
 895			struct net *net = read_pnet(&dp->net);
 896
 897			ovs_fragment(net, vport, skb, mru, key);
 898		} else {
 899			kfree_skb(skb);
 900		}
 901	} else {
 902		kfree_skb(skb);
 903	}
 904}
 905
 906static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 907			    struct sw_flow_key *key, const struct nlattr *attr,
 908			    const struct nlattr *actions, int actions_len,
 909			    uint32_t cutlen)
 910{
 911	struct dp_upcall_info upcall;
 912	const struct nlattr *a;
 913	int rem;
 914
 915	memset(&upcall, 0, sizeof(upcall));
 916	upcall.cmd = OVS_PACKET_CMD_ACTION;
 917	upcall.mru = OVS_CB(skb)->mru;
 918
 919	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 920	     a = nla_next(a, &rem)) {
 921		switch (nla_type(a)) {
 922		case OVS_USERSPACE_ATTR_USERDATA:
 923			upcall.userdata = a;
 924			break;
 925
 926		case OVS_USERSPACE_ATTR_PID:
 927			upcall.portid = nla_get_u32(a);
 
 
 
 
 
 
 928			break;
 929
 930		case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
 931			/* Get out tunnel info. */
 932			struct vport *vport;
 933
 934			vport = ovs_vport_rcu(dp, nla_get_u32(a));
 935			if (vport) {
 936				int err;
 937
 938				err = dev_fill_metadata_dst(vport->dev, skb);
 939				if (!err)
 940					upcall.egress_tun_info = skb_tunnel_info(skb);
 941			}
 942
 943			break;
 944		}
 945
 946		case OVS_USERSPACE_ATTR_ACTIONS: {
 947			/* Include actions. */
 948			upcall.actions = actions;
 949			upcall.actions_len = actions_len;
 950			break;
 951		}
 952
 953		} /* End of switch. */
 954	}
 955
 956	return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
 957}
 958
 959static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb,
 960				     struct sw_flow_key *key,
 961				     const struct nlattr *attr)
 962{
 963	/* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */
 964	struct nlattr *actions = nla_data(attr);
 965
 966	if (nla_len(actions))
 967		return clone_execute(dp, skb, key, 0, nla_data(actions),
 968				     nla_len(actions), true, false);
 969
 970	consume_skb(skb);
 971	return 0;
 972}
 973
 974/* When 'last' is true, sample() should always consume the 'skb'.
 975 * Otherwise, sample() should keep 'skb' intact regardless what
 976 * actions are executed within sample().
 977 */
 978static int sample(struct datapath *dp, struct sk_buff *skb,
 979		  struct sw_flow_key *key, const struct nlattr *attr,
 980		  bool last)
 981{
 982	struct nlattr *actions;
 983	struct nlattr *sample_arg;
 984	int rem = nla_len(attr);
 985	const struct sample_arg *arg;
 986	bool clone_flow_key;
 987
 988	/* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
 989	sample_arg = nla_data(attr);
 990	arg = nla_data(sample_arg);
 991	actions = nla_next(sample_arg, &rem);
 992
 993	if ((arg->probability != U32_MAX) &&
 994	    (!arg->probability || prandom_u32() > arg->probability)) {
 995		if (last)
 996			consume_skb(skb);
 997		return 0;
 998	}
 999
1000	clone_flow_key = !arg->exec;
1001	return clone_execute(dp, skb, key, 0, actions, rem, last,
1002			     clone_flow_key);
1003}
1004
1005/* When 'last' is true, clone() should always consume the 'skb'.
1006 * Otherwise, clone() should keep 'skb' intact regardless what
1007 * actions are executed within clone().
1008 */
1009static int clone(struct datapath *dp, struct sk_buff *skb,
1010		 struct sw_flow_key *key, const struct nlattr *attr,
1011		 bool last)
1012{
1013	struct nlattr *actions;
1014	struct nlattr *clone_arg;
1015	int rem = nla_len(attr);
1016	bool dont_clone_flow_key;
1017
1018	/* The first action is always 'OVS_CLONE_ATTR_ARG'. */
1019	clone_arg = nla_data(attr);
1020	dont_clone_flow_key = nla_get_u32(clone_arg);
1021	actions = nla_next(clone_arg, &rem);
1022
1023	return clone_execute(dp, skb, key, 0, actions, rem, last,
1024			     !dont_clone_flow_key);
1025}
1026
1027static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
1028			 const struct nlattr *attr)
1029{
1030	struct ovs_action_hash *hash_act = nla_data(attr);
1031	u32 hash = 0;
1032
1033	/* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
1034	hash = skb_get_hash(skb);
1035	hash = jhash_1word(hash, hash_act->hash_basis);
1036	if (!hash)
1037		hash = 0x1;
1038
1039	key->ovs_flow_hash = hash;
1040}
1041
1042static int execute_set_action(struct sk_buff *skb,
1043			      struct sw_flow_key *flow_key,
1044			      const struct nlattr *a)
1045{
1046	/* Only tunnel set execution is supported without a mask. */
1047	if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1048		struct ovs_tunnel_info *tun = nla_data(a);
1049
1050		skb_dst_drop(skb);
1051		dst_hold((struct dst_entry *)tun->tun_dst);
1052		skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
1053		return 0;
1054	}
1055
1056	return -EINVAL;
1057}
1058
1059/* Mask is at the midpoint of the data. */
1060#define get_mask(a, type) ((const type)nla_data(a) + 1)
1061
1062static int execute_masked_set_action(struct sk_buff *skb,
1063				     struct sw_flow_key *flow_key,
1064				     const struct nlattr *a)
1065{
1066	int err = 0;
1067
1068	switch (nla_type(a)) {
1069	case OVS_KEY_ATTR_PRIORITY:
1070		OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1071			       *get_mask(a, u32 *));
1072		flow_key->phy.priority = skb->priority;
1073		break;
1074
1075	case OVS_KEY_ATTR_SKB_MARK:
1076		OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1077		flow_key->phy.skb_mark = skb->mark;
1078		break;
1079
1080	case OVS_KEY_ATTR_TUNNEL_INFO:
1081		/* Masked data not supported for tunnel. */
1082		err = -EINVAL;
1083		break;
1084
1085	case OVS_KEY_ATTR_ETHERNET:
1086		err = set_eth_addr(skb, flow_key, nla_data(a),
1087				   get_mask(a, struct ovs_key_ethernet *));
1088		break;
1089
1090	case OVS_KEY_ATTR_NSH:
1091		err = set_nsh(skb, flow_key, a);
1092		break;
1093
1094	case OVS_KEY_ATTR_IPV4:
1095		err = set_ipv4(skb, flow_key, nla_data(a),
1096			       get_mask(a, struct ovs_key_ipv4 *));
1097		break;
1098
1099	case OVS_KEY_ATTR_IPV6:
1100		err = set_ipv6(skb, flow_key, nla_data(a),
1101			       get_mask(a, struct ovs_key_ipv6 *));
1102		break;
1103
1104	case OVS_KEY_ATTR_TCP:
1105		err = set_tcp(skb, flow_key, nla_data(a),
1106			      get_mask(a, struct ovs_key_tcp *));
1107		break;
1108
1109	case OVS_KEY_ATTR_UDP:
1110		err = set_udp(skb, flow_key, nla_data(a),
1111			      get_mask(a, struct ovs_key_udp *));
1112		break;
1113
1114	case OVS_KEY_ATTR_SCTP:
1115		err = set_sctp(skb, flow_key, nla_data(a),
1116			       get_mask(a, struct ovs_key_sctp *));
1117		break;
1118
1119	case OVS_KEY_ATTR_MPLS:
1120		err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1121								    __be32 *));
1122		break;
1123
1124	case OVS_KEY_ATTR_CT_STATE:
1125	case OVS_KEY_ATTR_CT_ZONE:
1126	case OVS_KEY_ATTR_CT_MARK:
1127	case OVS_KEY_ATTR_CT_LABELS:
1128	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1129	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1130		err = -EINVAL;
1131		break;
1132	}
1133
1134	return err;
1135}
1136
1137static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1138			  struct sw_flow_key *key,
1139			  const struct nlattr *a, bool last)
1140{
1141	u32 recirc_id;
1142
1143	if (!is_flow_key_valid(key)) {
1144		int err;
1145
1146		err = ovs_flow_key_update(skb, key);
1147		if (err)
1148			return err;
1149	}
1150	BUG_ON(!is_flow_key_valid(key));
1151
1152	recirc_id = nla_get_u32(a);
1153	return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
1154}
1155
1156static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
1157				 struct sw_flow_key *key,
1158				 const struct nlattr *attr, bool last)
1159{
1160	struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
1161	const struct nlattr *actions, *cpl_arg;
1162	int len, max_len, rem = nla_len(attr);
1163	const struct check_pkt_len_arg *arg;
1164	bool clone_flow_key;
1165
1166	/* The first netlink attribute in 'attr' is always
1167	 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
1168	 */
1169	cpl_arg = nla_data(attr);
1170	arg = nla_data(cpl_arg);
1171
1172	len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
1173	max_len = arg->pkt_len;
1174
1175	if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) ||
1176	    len <= max_len) {
1177		/* Second netlink attribute in 'attr' is always
1178		 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
1179		 */
1180		actions = nla_next(cpl_arg, &rem);
1181		clone_flow_key = !arg->exec_for_lesser_equal;
1182	} else {
1183		/* Third netlink attribute in 'attr' is always
1184		 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
1185		 */
1186		actions = nla_next(cpl_arg, &rem);
1187		actions = nla_next(actions, &rem);
1188		clone_flow_key = !arg->exec_for_greater;
1189	}
1190
1191	return clone_execute(dp, skb, key, 0, nla_data(actions),
1192			     nla_len(actions), last, clone_flow_key);
1193}
1194
1195static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key)
1196{
1197	int err;
1198
1199	if (skb->protocol == htons(ETH_P_IPV6)) {
1200		struct ipv6hdr *nh;
1201
1202		err = skb_ensure_writable(skb, skb_network_offset(skb) +
1203					  sizeof(*nh));
1204		if (unlikely(err))
1205			return err;
1206
1207		nh = ipv6_hdr(skb);
1208
1209		if (nh->hop_limit <= 1)
1210			return -EHOSTUNREACH;
1211
1212		key->ip.ttl = --nh->hop_limit;
1213	} else if (skb->protocol == htons(ETH_P_IP)) {
1214		struct iphdr *nh;
1215		u8 old_ttl;
1216
1217		err = skb_ensure_writable(skb, skb_network_offset(skb) +
1218					  sizeof(*nh));
1219		if (unlikely(err))
1220			return err;
1221
1222		nh = ip_hdr(skb);
1223		if (nh->ttl <= 1)
1224			return -EHOSTUNREACH;
1225
1226		old_ttl = nh->ttl--;
1227		csum_replace2(&nh->check, htons(old_ttl << 8),
1228			      htons(nh->ttl << 8));
1229		key->ip.ttl = nh->ttl;
1230	}
1231	return 0;
1232}
1233
1234/* Execute a list of actions against 'skb'. */
1235static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1236			      struct sw_flow_key *key,
1237			      const struct nlattr *attr, int len)
1238{
1239	const struct nlattr *a;
1240	int rem;
1241
1242	for (a = attr, rem = len; rem > 0;
1243	     a = nla_next(a, &rem)) {
1244		int err = 0;
1245
1246		if (trace_ovs_do_execute_action_enabled())
1247			trace_ovs_do_execute_action(dp, skb, key, a, rem);
1248
1249		switch (nla_type(a)) {
1250		case OVS_ACTION_ATTR_OUTPUT: {
1251			int port = nla_get_u32(a);
1252			struct sk_buff *clone;
1253
1254			/* Every output action needs a separate clone
1255			 * of 'skb', In case the output action is the
1256			 * last action, cloning can be avoided.
1257			 */
1258			if (nla_is_last(a, rem)) {
1259				do_output(dp, skb, port, key);
1260				/* 'skb' has been used for output.
1261				 */
1262				return 0;
1263			}
1264
1265			clone = skb_clone(skb, GFP_ATOMIC);
1266			if (clone)
1267				do_output(dp, clone, port, key);
1268			OVS_CB(skb)->cutlen = 0;
1269			break;
1270		}
1271
1272		case OVS_ACTION_ATTR_TRUNC: {
1273			struct ovs_action_trunc *trunc = nla_data(a);
1274
1275			if (skb->len > trunc->max_len)
1276				OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1277			break;
1278		}
1279
1280		case OVS_ACTION_ATTR_USERSPACE:
1281			output_userspace(dp, skb, key, a, attr,
1282						     len, OVS_CB(skb)->cutlen);
1283			OVS_CB(skb)->cutlen = 0;
1284			break;
1285
1286		case OVS_ACTION_ATTR_HASH:
1287			execute_hash(skb, key, a);
1288			break;
1289
1290		case OVS_ACTION_ATTR_PUSH_MPLS: {
1291			struct ovs_action_push_mpls *mpls = nla_data(a);
1292
1293			err = push_mpls(skb, key, mpls->mpls_lse,
1294					mpls->mpls_ethertype, skb->mac_len);
1295			break;
1296		}
1297		case OVS_ACTION_ATTR_ADD_MPLS: {
1298			struct ovs_action_add_mpls *mpls = nla_data(a);
1299			__u16 mac_len = 0;
1300
1301			if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK)
1302				mac_len = skb->mac_len;
1303
1304			err = push_mpls(skb, key, mpls->mpls_lse,
1305					mpls->mpls_ethertype, mac_len);
1306			break;
1307		}
1308		case OVS_ACTION_ATTR_POP_MPLS:
1309			err = pop_mpls(skb, key, nla_get_be16(a));
1310			break;
1311
1312		case OVS_ACTION_ATTR_PUSH_VLAN:
1313			err = push_vlan(skb, key, nla_data(a));
1314			break;
1315
1316		case OVS_ACTION_ATTR_POP_VLAN:
1317			err = pop_vlan(skb, key);
1318			break;
1319
1320		case OVS_ACTION_ATTR_RECIRC: {
1321			bool last = nla_is_last(a, rem);
1322
1323			err = execute_recirc(dp, skb, key, a, last);
1324			if (last) {
1325				/* If this is the last action, the skb has
1326				 * been consumed or freed.
1327				 * Return immediately.
1328				 */
1329				return err;
1330			}
1331			break;
1332		}
1333
1334		case OVS_ACTION_ATTR_SET:
1335			err = execute_set_action(skb, key, nla_data(a));
1336			break;
1337
1338		case OVS_ACTION_ATTR_SET_MASKED:
1339		case OVS_ACTION_ATTR_SET_TO_MASKED:
1340			err = execute_masked_set_action(skb, key, nla_data(a));
1341			break;
1342
1343		case OVS_ACTION_ATTR_SAMPLE: {
1344			bool last = nla_is_last(a, rem);
1345
1346			err = sample(dp, skb, key, a, last);
1347			if (last)
1348				return err;
1349
1350			break;
1351		}
1352
1353		case OVS_ACTION_ATTR_CT:
1354			if (!is_flow_key_valid(key)) {
1355				err = ovs_flow_key_update(skb, key);
1356				if (err)
1357					return err;
1358			}
1359
1360			err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1361					     nla_data(a));
1362
1363			/* Hide stolen IP fragments from user space. */
1364			if (err)
1365				return err == -EINPROGRESS ? 0 : err;
1366			break;
1367
1368		case OVS_ACTION_ATTR_CT_CLEAR:
1369			err = ovs_ct_clear(skb, key);
1370			break;
1371
1372		case OVS_ACTION_ATTR_PUSH_ETH:
1373			err = push_eth(skb, key, nla_data(a));
1374			break;
1375
1376		case OVS_ACTION_ATTR_POP_ETH:
1377			err = pop_eth(skb, key);
1378			break;
1379
1380		case OVS_ACTION_ATTR_PUSH_NSH: {
1381			u8 buffer[NSH_HDR_MAX_LEN];
1382			struct nshhdr *nh = (struct nshhdr *)buffer;
1383
1384			err = nsh_hdr_from_nlattr(nla_data(a), nh,
1385						  NSH_HDR_MAX_LEN);
1386			if (unlikely(err))
1387				break;
1388			err = push_nsh(skb, key, nh);
1389			break;
1390		}
1391
1392		case OVS_ACTION_ATTR_POP_NSH:
1393			err = pop_nsh(skb, key);
1394			break;
1395
1396		case OVS_ACTION_ATTR_METER:
1397			if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
1398				consume_skb(skb);
1399				return 0;
1400			}
1401			break;
1402
1403		case OVS_ACTION_ATTR_CLONE: {
1404			bool last = nla_is_last(a, rem);
1405
1406			err = clone(dp, skb, key, a, last);
1407			if (last)
1408				return err;
1409
1410			break;
1411		}
1412
1413		case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
1414			bool last = nla_is_last(a, rem);
1415
1416			err = execute_check_pkt_len(dp, skb, key, a, last);
1417			if (last)
1418				return err;
1419
1420			break;
1421		}
1422
1423		case OVS_ACTION_ATTR_DEC_TTL:
1424			err = execute_dec_ttl(skb, key);
1425			if (err == -EHOSTUNREACH)
1426				return dec_ttl_exception_handler(dp, skb,
1427								 key, a);
1428			break;
1429		}
1430
1431		if (unlikely(err)) {
1432			kfree_skb(skb);
1433			return err;
1434		}
1435	}
1436
1437	consume_skb(skb);
1438	return 0;
1439}
1440
1441/* Execute the actions on the clone of the packet. The effect of the
1442 * execution does not affect the original 'skb' nor the original 'key'.
1443 *
1444 * The execution may be deferred in case the actions can not be executed
1445 * immediately.
1446 */
1447static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1448			 struct sw_flow_key *key, u32 recirc_id,
1449			 const struct nlattr *actions, int len,
1450			 bool last, bool clone_flow_key)
1451{
1452	struct deferred_action *da;
1453	struct sw_flow_key *clone;
1454
1455	skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1456	if (!skb) {
1457		/* Out of memory, skip this action.
1458		 */
1459		return 0;
1460	}
1461
1462	/* When clone_flow_key is false, the 'key' will not be change
1463	 * by the actions, then the 'key' can be used directly.
1464	 * Otherwise, try to clone key from the next recursion level of
1465	 * 'flow_keys'. If clone is successful, execute the actions
1466	 * without deferring.
1467	 */
1468	clone = clone_flow_key ? clone_key(key) : key;
1469	if (clone) {
1470		int err = 0;
1471
1472		if (actions) { /* Sample action */
1473			if (clone_flow_key)
1474				__this_cpu_inc(exec_actions_level);
1475
1476			err = do_execute_actions(dp, skb, clone,
1477						 actions, len);
1478
1479			if (clone_flow_key)
1480				__this_cpu_dec(exec_actions_level);
1481		} else { /* Recirc action */
1482			clone->recirc_id = recirc_id;
1483			ovs_dp_process_packet(skb, clone);
1484		}
1485		return err;
1486	}
1487
1488	/* Out of 'flow_keys' space. Defer actions */
1489	da = add_deferred_actions(skb, key, actions, len);
1490	if (da) {
1491		if (!actions) { /* Recirc action */
1492			key = &da->pkt_key;
1493			key->recirc_id = recirc_id;
1494		}
1495	} else {
1496		/* Out of per CPU action FIFO space. Drop the 'skb' and
1497		 * log an error.
1498		 */
1499		kfree_skb(skb);
1500
1501		if (net_ratelimit()) {
1502			if (actions) { /* Sample action */
1503				pr_warn("%s: deferred action limit reached, drop sample action\n",
1504					ovs_dp_name(dp));
1505			} else {  /* Recirc action */
1506				pr_warn("%s: deferred action limit reached, drop recirc action\n",
1507					ovs_dp_name(dp));
1508			}
1509		}
1510	}
1511	return 0;
1512}
1513
1514static void process_deferred_actions(struct datapath *dp)
1515{
1516	struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1517
1518	/* Do not touch the FIFO in case there is no deferred actions. */
1519	if (action_fifo_is_empty(fifo))
1520		return;
1521
1522	/* Finishing executing all deferred actions. */
1523	do {
1524		struct deferred_action *da = action_fifo_get(fifo);
1525		struct sk_buff *skb = da->skb;
1526		struct sw_flow_key *key = &da->pkt_key;
1527		const struct nlattr *actions = da->actions;
1528		int actions_len = da->actions_len;
1529
1530		if (actions)
1531			do_execute_actions(dp, skb, key, actions, actions_len);
1532		else
1533			ovs_dp_process_packet(skb, key);
1534	} while (!action_fifo_is_empty(fifo));
1535
1536	/* Reset FIFO for the next packet.  */
1537	action_fifo_init(fifo);
1538}
1539
1540/* Execute a list of actions against 'skb'. */
1541int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1542			const struct sw_flow_actions *acts,
1543			struct sw_flow_key *key)
1544{
1545	int err, level;
1546
1547	level = __this_cpu_inc_return(exec_actions_level);
1548	if (unlikely(level > OVS_RECURSION_LIMIT)) {
1549		net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1550				     ovs_dp_name(dp));
1551		kfree_skb(skb);
1552		err = -ENETDOWN;
1553		goto out;
1554	}
1555
1556	OVS_CB(skb)->acts_origlen = acts->orig_len;
1557	err = do_execute_actions(dp, skb, key,
1558				 acts->actions, acts->actions_len);
1559
1560	if (level == 1)
1561		process_deferred_actions(dp);
1562
1563out:
1564	__this_cpu_dec(exec_actions_level);
1565	return err;
1566}
1567
1568int action_fifos_init(void)
1569{
1570	action_fifos = alloc_percpu(struct action_fifo);
1571	if (!action_fifos)
1572		return -ENOMEM;
1573
1574	flow_keys = alloc_percpu(struct action_flow_keys);
1575	if (!flow_keys) {
1576		free_percpu(action_fifos);
1577		return -ENOMEM;
1578	}
1579
1580	return 0;
1581}
1582
1583void action_fifos_exit(void)
1584{
1585	free_percpu(action_fifos);
1586	free_percpu(flow_keys);
1587}
v6.2
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2007-2017 Nicira, Inc.
   4 */
   5
   6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7
   8#include <linux/skbuff.h>
   9#include <linux/in.h>
  10#include <linux/ip.h>
  11#include <linux/openvswitch.h>
  12#include <linux/sctp.h>
  13#include <linux/tcp.h>
  14#include <linux/udp.h>
  15#include <linux/in6.h>
  16#include <linux/if_arp.h>
  17#include <linux/if_vlan.h>
  18
  19#include <net/dst.h>
  20#include <net/ip.h>
  21#include <net/ipv6.h>
  22#include <net/ip6_fib.h>
  23#include <net/checksum.h>
  24#include <net/dsfield.h>
  25#include <net/mpls.h>
  26#include <net/sctp/checksum.h>
  27
  28#include "datapath.h"
  29#include "flow.h"
  30#include "conntrack.h"
  31#include "vport.h"
  32#include "flow_netlink.h"
  33#include "openvswitch_trace.h"
  34
  35struct deferred_action {
  36	struct sk_buff *skb;
  37	const struct nlattr *actions;
  38	int actions_len;
  39
  40	/* Store pkt_key clone when creating deferred action. */
  41	struct sw_flow_key pkt_key;
  42};
  43
  44#define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
  45struct ovs_frag_data {
  46	unsigned long dst;
  47	struct vport *vport;
  48	struct ovs_skb_cb cb;
  49	__be16 inner_protocol;
  50	u16 network_offset;	/* valid only for MPLS */
  51	u16 vlan_tci;
  52	__be16 vlan_proto;
  53	unsigned int l2_len;
  54	u8 mac_proto;
  55	u8 l2_data[MAX_L2_LEN];
  56};
  57
  58static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
  59
  60#define DEFERRED_ACTION_FIFO_SIZE 10
  61#define OVS_RECURSION_LIMIT 5
  62#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
  63struct action_fifo {
  64	int head;
  65	int tail;
  66	/* Deferred action fifo queue storage. */
  67	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
  68};
  69
  70struct action_flow_keys {
  71	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
  72};
  73
  74static struct action_fifo __percpu *action_fifos;
  75static struct action_flow_keys __percpu *flow_keys;
  76static DEFINE_PER_CPU(int, exec_actions_level);
  77
  78/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
  79 * space. Return NULL if out of key spaces.
  80 */
  81static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
  82{
  83	struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
  84	int level = this_cpu_read(exec_actions_level);
  85	struct sw_flow_key *key = NULL;
  86
  87	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
  88		key = &keys->key[level - 1];
  89		*key = *key_;
  90	}
  91
  92	return key;
  93}
  94
  95static void action_fifo_init(struct action_fifo *fifo)
  96{
  97	fifo->head = 0;
  98	fifo->tail = 0;
  99}
 100
 101static bool action_fifo_is_empty(const struct action_fifo *fifo)
 102{
 103	return (fifo->head == fifo->tail);
 104}
 105
 106static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
 107{
 108	if (action_fifo_is_empty(fifo))
 109		return NULL;
 110
 111	return &fifo->fifo[fifo->tail++];
 112}
 113
 114static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
 115{
 116	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
 117		return NULL;
 118
 119	return &fifo->fifo[fifo->head++];
 120}
 121
 122/* Return true if fifo is not full */
 123static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
 124				    const struct sw_flow_key *key,
 125				    const struct nlattr *actions,
 126				    const int actions_len)
 127{
 128	struct action_fifo *fifo;
 129	struct deferred_action *da;
 130
 131	fifo = this_cpu_ptr(action_fifos);
 132	da = action_fifo_put(fifo);
 133	if (da) {
 134		da->skb = skb;
 135		da->actions = actions;
 136		da->actions_len = actions_len;
 137		da->pkt_key = *key;
 138	}
 139
 140	return da;
 141}
 142
 143static void invalidate_flow_key(struct sw_flow_key *key)
 144{
 145	key->mac_proto |= SW_FLOW_KEY_INVALID;
 146}
 147
 148static bool is_flow_key_valid(const struct sw_flow_key *key)
 149{
 150	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
 151}
 152
 153static int clone_execute(struct datapath *dp, struct sk_buff *skb,
 154			 struct sw_flow_key *key,
 155			 u32 recirc_id,
 156			 const struct nlattr *actions, int len,
 157			 bool last, bool clone_flow_key);
 158
 159static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 160			      struct sw_flow_key *key,
 161			      const struct nlattr *attr, int len);
 162
 163static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 164		     __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len)
 165{
 166	int err;
 167
 168	err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len);
 169	if (err)
 170		return err;
 171
 172	if (!mac_len)
 173		key->mac_proto = MAC_PROTO_NONE;
 174
 175	invalidate_flow_key(key);
 176	return 0;
 177}
 178
 179static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 180		    const __be16 ethertype)
 181{
 182	int err;
 183
 184	err = skb_mpls_pop(skb, ethertype, skb->mac_len,
 185			   ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET);
 186	if (err)
 187		return err;
 188
 189	if (ethertype == htons(ETH_P_TEB))
 190		key->mac_proto = MAC_PROTO_ETHERNET;
 191
 192	invalidate_flow_key(key);
 193	return 0;
 194}
 195
 196static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 197		    const __be32 *mpls_lse, const __be32 *mask)
 198{
 199	struct mpls_shim_hdr *stack;
 200	__be32 lse;
 201	int err;
 202
 203	if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN))
 204		return -ENOMEM;
 205
 206	stack = mpls_hdr(skb);
 207	lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
 208	err = skb_mpls_update_lse(skb, lse);
 209	if (err)
 210		return err;
 211
 212	flow_key->mpls.lse[0] = lse;
 213	return 0;
 214}
 215
 216static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 217{
 218	int err;
 219
 220	err = skb_vlan_pop(skb);
 221	if (skb_vlan_tag_present(skb)) {
 222		invalidate_flow_key(key);
 223	} else {
 224		key->eth.vlan.tci = 0;
 225		key->eth.vlan.tpid = 0;
 226	}
 227	return err;
 228}
 229
 230static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 231		     const struct ovs_action_push_vlan *vlan)
 232{
 233	if (skb_vlan_tag_present(skb)) {
 234		invalidate_flow_key(key);
 235	} else {
 236		key->eth.vlan.tci = vlan->vlan_tci;
 237		key->eth.vlan.tpid = vlan->vlan_tpid;
 238	}
 239	return skb_vlan_push(skb, vlan->vlan_tpid,
 240			     ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
 241}
 242
 243/* 'src' is already properly masked. */
 244static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 245{
 246	u16 *dst = (u16 *)dst_;
 247	const u16 *src = (const u16 *)src_;
 248	const u16 *mask = (const u16 *)mask_;
 249
 250	OVS_SET_MASKED(dst[0], src[0], mask[0]);
 251	OVS_SET_MASKED(dst[1], src[1], mask[1]);
 252	OVS_SET_MASKED(dst[2], src[2], mask[2]);
 253}
 254
 255static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 256			const struct ovs_key_ethernet *key,
 257			const struct ovs_key_ethernet *mask)
 258{
 259	int err;
 260
 261	err = skb_ensure_writable(skb, ETH_HLEN);
 262	if (unlikely(err))
 263		return err;
 264
 265	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 266
 267	ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 268			       mask->eth_src);
 269	ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 270			       mask->eth_dst);
 271
 272	skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 273
 274	ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 275	ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 276	return 0;
 277}
 278
 279/* pop_eth does not support VLAN packets as this action is never called
 280 * for them.
 281 */
 282static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
 283{
 284	int err;
 285
 286	err = skb_eth_pop(skb);
 287	if (err)
 288		return err;
 289
 290	/* safe right before invalidate_flow_key */
 291	key->mac_proto = MAC_PROTO_NONE;
 292	invalidate_flow_key(key);
 293	return 0;
 294}
 295
 296static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
 297		    const struct ovs_action_push_eth *ethh)
 298{
 299	int err;
 300
 301	err = skb_eth_push(skb, ethh->addresses.eth_dst,
 302			   ethh->addresses.eth_src);
 303	if (err)
 304		return err;
 305
 306	/* safe right before invalidate_flow_key */
 307	key->mac_proto = MAC_PROTO_ETHERNET;
 308	invalidate_flow_key(key);
 309	return 0;
 310}
 311
 312static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key,
 313		    const struct nshhdr *nh)
 314{
 315	int err;
 316
 317	err = nsh_push(skb, nh);
 318	if (err)
 319		return err;
 320
 321	/* safe right before invalidate_flow_key */
 322	key->mac_proto = MAC_PROTO_NONE;
 323	invalidate_flow_key(key);
 324	return 0;
 325}
 326
 327static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 328{
 329	int err;
 330
 331	err = nsh_pop(skb);
 332	if (err)
 333		return err;
 334
 335	/* safe right before invalidate_flow_key */
 336	if (skb->protocol == htons(ETH_P_TEB))
 337		key->mac_proto = MAC_PROTO_ETHERNET;
 338	else
 339		key->mac_proto = MAC_PROTO_NONE;
 340	invalidate_flow_key(key);
 341	return 0;
 342}
 343
 344static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
 345				  __be32 addr, __be32 new_addr)
 346{
 347	int transport_len = skb->len - skb_transport_offset(skb);
 348
 349	if (nh->frag_off & htons(IP_OFFSET))
 350		return;
 351
 352	if (nh->protocol == IPPROTO_TCP) {
 353		if (likely(transport_len >= sizeof(struct tcphdr)))
 354			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 355						 addr, new_addr, true);
 356	} else if (nh->protocol == IPPROTO_UDP) {
 357		if (likely(transport_len >= sizeof(struct udphdr))) {
 358			struct udphdr *uh = udp_hdr(skb);
 359
 360			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 361				inet_proto_csum_replace4(&uh->check, skb,
 362							 addr, new_addr, true);
 363				if (!uh->check)
 364					uh->check = CSUM_MANGLED_0;
 365			}
 366		}
 367	}
 368}
 369
 370static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 371			__be32 *addr, __be32 new_addr)
 372{
 373	update_ip_l4_checksum(skb, nh, *addr, new_addr);
 374	csum_replace4(&nh->check, *addr, new_addr);
 375	skb_clear_hash(skb);
 376	ovs_ct_clear(skb, NULL);
 377	*addr = new_addr;
 378}
 379
 380static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 381				 __be32 addr[4], const __be32 new_addr[4])
 382{
 383	int transport_len = skb->len - skb_transport_offset(skb);
 384
 385	if (l4_proto == NEXTHDR_TCP) {
 386		if (likely(transport_len >= sizeof(struct tcphdr)))
 387			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 388						  addr, new_addr, true);
 389	} else if (l4_proto == NEXTHDR_UDP) {
 390		if (likely(transport_len >= sizeof(struct udphdr))) {
 391			struct udphdr *uh = udp_hdr(skb);
 392
 393			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 394				inet_proto_csum_replace16(&uh->check, skb,
 395							  addr, new_addr, true);
 396				if (!uh->check)
 397					uh->check = CSUM_MANGLED_0;
 398			}
 399		}
 400	} else if (l4_proto == NEXTHDR_ICMP) {
 401		if (likely(transport_len >= sizeof(struct icmp6hdr)))
 402			inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 403						  skb, addr, new_addr, true);
 404	}
 405}
 406
 407static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 408			   const __be32 mask[4], __be32 masked[4])
 409{
 410	masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
 411	masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
 412	masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
 413	masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
 414}
 415
 416static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 417			  __be32 addr[4], const __be32 new_addr[4],
 418			  bool recalculate_csum)
 419{
 420	if (recalculate_csum)
 421		update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 422
 423	skb_clear_hash(skb);
 424	ovs_ct_clear(skb, NULL);
 425	memcpy(addr, new_addr, sizeof(__be32[4]));
 426}
 427
 428static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask)
 429{
 430	u8 old_ipv6_tclass = ipv6_get_dsfield(nh);
 431
 432	ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask);
 433
 434	if (skb->ip_summed == CHECKSUM_COMPLETE)
 435		csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12),
 436			     (__force __wsum)(ipv6_tclass << 12));
 437
 438	ipv6_change_dsfield(nh, ~mask, ipv6_tclass);
 439}
 440
 441static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask)
 442{
 443	u32 ofl;
 444
 445	ofl = nh->flow_lbl[0] << 16 |  nh->flow_lbl[1] << 8 |  nh->flow_lbl[2];
 446	fl = OVS_MASKED(ofl, fl, mask);
 447
 448	/* Bits 21-24 are always unmasked, so this retains their values. */
 449	nh->flow_lbl[0] = (u8)(fl >> 16);
 450	nh->flow_lbl[1] = (u8)(fl >> 8);
 451	nh->flow_lbl[2] = (u8)fl;
 452
 453	if (skb->ip_summed == CHECKSUM_COMPLETE)
 454		csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl));
 455}
 456
 457static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask)
 458{
 459	new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask);
 460
 461	if (skb->ip_summed == CHECKSUM_COMPLETE)
 462		csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8),
 463			     (__force __wsum)(new_ttl << 8));
 464	nh->hop_limit = new_ttl;
 465}
 466
 467static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 468		       u8 mask)
 469{
 470	new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
 471
 472	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 473	nh->ttl = new_ttl;
 474}
 475
 476static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 477		    const struct ovs_key_ipv4 *key,
 478		    const struct ovs_key_ipv4 *mask)
 479{
 480	struct iphdr *nh;
 481	__be32 new_addr;
 482	int err;
 483
 484	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 485				  sizeof(struct iphdr));
 486	if (unlikely(err))
 487		return err;
 488
 489	nh = ip_hdr(skb);
 490
 491	/* Setting an IP addresses is typically only a side effect of
 492	 * matching on them in the current userspace implementation, so it
 493	 * makes sense to check if the value actually changed.
 494	 */
 495	if (mask->ipv4_src) {
 496		new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 497
 498		if (unlikely(new_addr != nh->saddr)) {
 499			set_ip_addr(skb, nh, &nh->saddr, new_addr);
 500			flow_key->ipv4.addr.src = new_addr;
 501		}
 502	}
 503	if (mask->ipv4_dst) {
 504		new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 505
 506		if (unlikely(new_addr != nh->daddr)) {
 507			set_ip_addr(skb, nh, &nh->daddr, new_addr);
 508			flow_key->ipv4.addr.dst = new_addr;
 509		}
 510	}
 511	if (mask->ipv4_tos) {
 512		ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 513		flow_key->ip.tos = nh->tos;
 514	}
 515	if (mask->ipv4_ttl) {
 516		set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 517		flow_key->ip.ttl = nh->ttl;
 518	}
 519
 520	return 0;
 521}
 522
 523static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 524{
 525	return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 526}
 527
 528static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 529		    const struct ovs_key_ipv6 *key,
 530		    const struct ovs_key_ipv6 *mask)
 531{
 532	struct ipv6hdr *nh;
 533	int err;
 534
 535	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 536				  sizeof(struct ipv6hdr));
 537	if (unlikely(err))
 538		return err;
 539
 540	nh = ipv6_hdr(skb);
 541
 542	/* Setting an IP addresses is typically only a side effect of
 543	 * matching on them in the current userspace implementation, so it
 544	 * makes sense to check if the value actually changed.
 545	 */
 546	if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 547		__be32 *saddr = (__be32 *)&nh->saddr;
 548		__be32 masked[4];
 549
 550		mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 551
 552		if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 553			set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
 554				      true);
 555			memcpy(&flow_key->ipv6.addr.src, masked,
 556			       sizeof(flow_key->ipv6.addr.src));
 557		}
 558	}
 559	if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 560		unsigned int offset = 0;
 561		int flags = IP6_FH_F_SKIP_RH;
 562		bool recalc_csum = true;
 563		__be32 *daddr = (__be32 *)&nh->daddr;
 564		__be32 masked[4];
 565
 566		mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 567
 568		if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 569			if (ipv6_ext_hdr(nh->nexthdr))
 570				recalc_csum = (ipv6_find_hdr(skb, &offset,
 571							     NEXTHDR_ROUTING,
 572							     NULL, &flags)
 573					       != NEXTHDR_ROUTING);
 574
 575			set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
 576				      recalc_csum);
 577			memcpy(&flow_key->ipv6.addr.dst, masked,
 578			       sizeof(flow_key->ipv6.addr.dst));
 579		}
 580	}
 581	if (mask->ipv6_tclass) {
 582		set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass);
 583		flow_key->ip.tos = ipv6_get_dsfield(nh);
 584	}
 585	if (mask->ipv6_label) {
 586		set_ipv6_fl(skb, nh, ntohl(key->ipv6_label),
 587			    ntohl(mask->ipv6_label));
 588		flow_key->ipv6.label =
 589		    *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 590	}
 591	if (mask->ipv6_hlimit) {
 592		set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit);
 
 593		flow_key->ip.ttl = nh->hop_limit;
 594	}
 595	return 0;
 596}
 597
 598static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
 599		   const struct nlattr *a)
 600{
 601	struct nshhdr *nh;
 602	size_t length;
 603	int err;
 604	u8 flags;
 605	u8 ttl;
 606	int i;
 607
 608	struct ovs_key_nsh key;
 609	struct ovs_key_nsh mask;
 610
 611	err = nsh_key_from_nlattr(a, &key, &mask);
 612	if (err)
 613		return err;
 614
 615	/* Make sure the NSH base header is there */
 616	if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
 617		return -ENOMEM;
 618
 619	nh = nsh_hdr(skb);
 620	length = nsh_hdr_len(nh);
 621
 622	/* Make sure the whole NSH header is there */
 623	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 624				       length);
 625	if (unlikely(err))
 626		return err;
 627
 628	nh = nsh_hdr(skb);
 629	skb_postpull_rcsum(skb, nh, length);
 630	flags = nsh_get_flags(nh);
 631	flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
 632	flow_key->nsh.base.flags = flags;
 633	ttl = nsh_get_ttl(nh);
 634	ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
 635	flow_key->nsh.base.ttl = ttl;
 636	nsh_set_flags_and_ttl(nh, flags, ttl);
 637	nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
 638				  mask.base.path_hdr);
 639	flow_key->nsh.base.path_hdr = nh->path_hdr;
 640	switch (nh->mdtype) {
 641	case NSH_M_TYPE1:
 642		for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
 643			nh->md1.context[i] =
 644			    OVS_MASKED(nh->md1.context[i], key.context[i],
 645				       mask.context[i]);
 646		}
 647		memcpy(flow_key->nsh.context, nh->md1.context,
 648		       sizeof(nh->md1.context));
 649		break;
 650	case NSH_M_TYPE2:
 651		memset(flow_key->nsh.context, 0,
 652		       sizeof(flow_key->nsh.context));
 653		break;
 654	default:
 655		return -EINVAL;
 656	}
 657	skb_postpush_rcsum(skb, nh, length);
 658	return 0;
 659}
 660
 661/* Must follow skb_ensure_writable() since that can move the skb data. */
 662static void set_tp_port(struct sk_buff *skb, __be16 *port,
 663			__be16 new_port, __sum16 *check)
 664{
 665	ovs_ct_clear(skb, NULL);
 666	inet_proto_csum_replace2(check, skb, *port, new_port, false);
 667	*port = new_port;
 668}
 669
 670static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 671		   const struct ovs_key_udp *key,
 672		   const struct ovs_key_udp *mask)
 673{
 674	struct udphdr *uh;
 675	__be16 src, dst;
 676	int err;
 677
 678	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 679				  sizeof(struct udphdr));
 680	if (unlikely(err))
 681		return err;
 682
 683	uh = udp_hdr(skb);
 684	/* Either of the masks is non-zero, so do not bother checking them. */
 685	src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
 686	dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 687
 688	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 689		if (likely(src != uh->source)) {
 690			set_tp_port(skb, &uh->source, src, &uh->check);
 691			flow_key->tp.src = src;
 692		}
 693		if (likely(dst != uh->dest)) {
 694			set_tp_port(skb, &uh->dest, dst, &uh->check);
 695			flow_key->tp.dst = dst;
 696		}
 697
 698		if (unlikely(!uh->check))
 699			uh->check = CSUM_MANGLED_0;
 700	} else {
 701		uh->source = src;
 702		uh->dest = dst;
 703		flow_key->tp.src = src;
 704		flow_key->tp.dst = dst;
 705		ovs_ct_clear(skb, NULL);
 706	}
 707
 708	skb_clear_hash(skb);
 709
 710	return 0;
 711}
 712
 713static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 714		   const struct ovs_key_tcp *key,
 715		   const struct ovs_key_tcp *mask)
 716{
 717	struct tcphdr *th;
 718	__be16 src, dst;
 719	int err;
 720
 721	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 722				  sizeof(struct tcphdr));
 723	if (unlikely(err))
 724		return err;
 725
 726	th = tcp_hdr(skb);
 727	src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
 728	if (likely(src != th->source)) {
 729		set_tp_port(skb, &th->source, src, &th->check);
 730		flow_key->tp.src = src;
 731	}
 732	dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 733	if (likely(dst != th->dest)) {
 734		set_tp_port(skb, &th->dest, dst, &th->check);
 735		flow_key->tp.dst = dst;
 736	}
 737	skb_clear_hash(skb);
 738
 739	return 0;
 740}
 741
 742static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 743		    const struct ovs_key_sctp *key,
 744		    const struct ovs_key_sctp *mask)
 745{
 746	unsigned int sctphoff = skb_transport_offset(skb);
 747	struct sctphdr *sh;
 748	__le32 old_correct_csum, new_csum, old_csum;
 749	int err;
 750
 751	err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 752	if (unlikely(err))
 753		return err;
 754
 755	sh = sctp_hdr(skb);
 756	old_csum = sh->checksum;
 757	old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 758
 759	sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
 760	sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 761
 762	new_csum = sctp_compute_cksum(skb, sctphoff);
 763
 764	/* Carry any checksum errors through. */
 765	sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 766
 767	skb_clear_hash(skb);
 768	ovs_ct_clear(skb, NULL);
 769
 770	flow_key->tp.src = sh->source;
 771	flow_key->tp.dst = sh->dest;
 772
 773	return 0;
 774}
 775
 776static int ovs_vport_output(struct net *net, struct sock *sk,
 777			    struct sk_buff *skb)
 778{
 779	struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
 780	struct vport *vport = data->vport;
 781
 782	if (skb_cow_head(skb, data->l2_len) < 0) {
 783		kfree_skb(skb);
 784		return -ENOMEM;
 785	}
 786
 787	__skb_dst_copy(skb, data->dst);
 788	*OVS_CB(skb) = data->cb;
 789	skb->inner_protocol = data->inner_protocol;
 790	if (data->vlan_tci & VLAN_CFI_MASK)
 791		__vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK);
 792	else
 793		__vlan_hwaccel_clear_tag(skb);
 794
 795	/* Reconstruct the MAC header.  */
 796	skb_push(skb, data->l2_len);
 797	memcpy(skb->data, &data->l2_data, data->l2_len);
 798	skb_postpush_rcsum(skb, skb->data, data->l2_len);
 799	skb_reset_mac_header(skb);
 800
 801	if (eth_p_mpls(skb->protocol)) {
 802		skb->inner_network_header = skb->network_header;
 803		skb_set_network_header(skb, data->network_offset);
 804		skb_reset_mac_len(skb);
 805	}
 806
 807	ovs_vport_send(vport, skb, data->mac_proto);
 808	return 0;
 809}
 810
 811static unsigned int
 812ovs_dst_get_mtu(const struct dst_entry *dst)
 813{
 814	return dst->dev->mtu;
 815}
 816
 817static struct dst_ops ovs_dst_ops = {
 818	.family = AF_UNSPEC,
 819	.mtu = ovs_dst_get_mtu,
 820};
 821
 822/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 823 * ovs_vport_output(), which is called once per fragmented packet.
 824 */
 825static void prepare_frag(struct vport *vport, struct sk_buff *skb,
 826			 u16 orig_network_offset, u8 mac_proto)
 827{
 828	unsigned int hlen = skb_network_offset(skb);
 829	struct ovs_frag_data *data;
 830
 831	data = this_cpu_ptr(&ovs_frag_data_storage);
 832	data->dst = skb->_skb_refdst;
 833	data->vport = vport;
 834	data->cb = *OVS_CB(skb);
 835	data->inner_protocol = skb->inner_protocol;
 836	data->network_offset = orig_network_offset;
 837	if (skb_vlan_tag_present(skb))
 838		data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
 839	else
 840		data->vlan_tci = 0;
 841	data->vlan_proto = skb->vlan_proto;
 842	data->mac_proto = mac_proto;
 843	data->l2_len = hlen;
 844	memcpy(&data->l2_data, skb->data, hlen);
 845
 846	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 847	skb_pull(skb, hlen);
 848}
 849
 850static void ovs_fragment(struct net *net, struct vport *vport,
 851			 struct sk_buff *skb, u16 mru,
 852			 struct sw_flow_key *key)
 853{
 854	u16 orig_network_offset = 0;
 855
 856	if (eth_p_mpls(skb->protocol)) {
 857		orig_network_offset = skb_network_offset(skb);
 858		skb->network_header = skb->inner_network_header;
 859	}
 860
 861	if (skb_network_offset(skb) > MAX_L2_LEN) {
 862		OVS_NLERR(1, "L2 header too long to fragment");
 863		goto err;
 864	}
 865
 866	if (key->eth.type == htons(ETH_P_IP)) {
 867		struct rtable ovs_rt = { 0 };
 868		unsigned long orig_dst;
 869
 870		prepare_frag(vport, skb, orig_network_offset,
 871			     ovs_key_mac_proto(key));
 872		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 873			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 874		ovs_rt.dst.dev = vport->dev;
 875
 876		orig_dst = skb->_skb_refdst;
 877		skb_dst_set_noref(skb, &ovs_rt.dst);
 878		IPCB(skb)->frag_max_size = mru;
 879
 880		ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
 881		refdst_drop(orig_dst);
 882	} else if (key->eth.type == htons(ETH_P_IPV6)) {
 883		unsigned long orig_dst;
 884		struct rt6_info ovs_rt;
 885
 886		prepare_frag(vport, skb, orig_network_offset,
 887			     ovs_key_mac_proto(key));
 888		memset(&ovs_rt, 0, sizeof(ovs_rt));
 889		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 890			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 891		ovs_rt.dst.dev = vport->dev;
 892
 893		orig_dst = skb->_skb_refdst;
 894		skb_dst_set_noref(skb, &ovs_rt.dst);
 895		IP6CB(skb)->frag_max_size = mru;
 896
 897		ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output);
 898		refdst_drop(orig_dst);
 899	} else {
 900		WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
 901			  ovs_vport_name(vport), ntohs(key->eth.type), mru,
 902			  vport->dev->mtu);
 903		goto err;
 904	}
 905
 906	return;
 907err:
 908	kfree_skb(skb);
 909}
 910
 911static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
 912		      struct sw_flow_key *key)
 913{
 914	struct vport *vport = ovs_vport_rcu(dp, out_port);
 915
 916	if (likely(vport)) {
 917		u16 mru = OVS_CB(skb)->mru;
 918		u32 cutlen = OVS_CB(skb)->cutlen;
 919
 920		if (unlikely(cutlen > 0)) {
 921			if (skb->len - cutlen > ovs_mac_header_len(key))
 922				pskb_trim(skb, skb->len - cutlen);
 923			else
 924				pskb_trim(skb, ovs_mac_header_len(key));
 925		}
 926
 927		if (likely(!mru ||
 928		           (skb->len <= mru + vport->dev->hard_header_len))) {
 929			ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
 930		} else if (mru <= vport->dev->mtu) {
 931			struct net *net = read_pnet(&dp->net);
 932
 933			ovs_fragment(net, vport, skb, mru, key);
 934		} else {
 935			kfree_skb(skb);
 936		}
 937	} else {
 938		kfree_skb(skb);
 939	}
 940}
 941
 942static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 943			    struct sw_flow_key *key, const struct nlattr *attr,
 944			    const struct nlattr *actions, int actions_len,
 945			    uint32_t cutlen)
 946{
 947	struct dp_upcall_info upcall;
 948	const struct nlattr *a;
 949	int rem;
 950
 951	memset(&upcall, 0, sizeof(upcall));
 952	upcall.cmd = OVS_PACKET_CMD_ACTION;
 953	upcall.mru = OVS_CB(skb)->mru;
 954
 955	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 956	     a = nla_next(a, &rem)) {
 957		switch (nla_type(a)) {
 958		case OVS_USERSPACE_ATTR_USERDATA:
 959			upcall.userdata = a;
 960			break;
 961
 962		case OVS_USERSPACE_ATTR_PID:
 963			if (dp->user_features &
 964			    OVS_DP_F_DISPATCH_UPCALL_PER_CPU)
 965				upcall.portid =
 966				  ovs_dp_get_upcall_portid(dp,
 967							   smp_processor_id());
 968			else
 969				upcall.portid = nla_get_u32(a);
 970			break;
 971
 972		case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
 973			/* Get out tunnel info. */
 974			struct vport *vport;
 975
 976			vport = ovs_vport_rcu(dp, nla_get_u32(a));
 977			if (vport) {
 978				int err;
 979
 980				err = dev_fill_metadata_dst(vport->dev, skb);
 981				if (!err)
 982					upcall.egress_tun_info = skb_tunnel_info(skb);
 983			}
 984
 985			break;
 986		}
 987
 988		case OVS_USERSPACE_ATTR_ACTIONS: {
 989			/* Include actions. */
 990			upcall.actions = actions;
 991			upcall.actions_len = actions_len;
 992			break;
 993		}
 994
 995		} /* End of switch. */
 996	}
 997
 998	return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
 999}
1000
1001static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb,
1002				     struct sw_flow_key *key,
1003				     const struct nlattr *attr)
1004{
1005	/* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */
1006	struct nlattr *actions = nla_data(attr);
1007
1008	if (nla_len(actions))
1009		return clone_execute(dp, skb, key, 0, nla_data(actions),
1010				     nla_len(actions), true, false);
1011
1012	consume_skb(skb);
1013	return 0;
1014}
1015
1016/* When 'last' is true, sample() should always consume the 'skb'.
1017 * Otherwise, sample() should keep 'skb' intact regardless what
1018 * actions are executed within sample().
1019 */
1020static int sample(struct datapath *dp, struct sk_buff *skb,
1021		  struct sw_flow_key *key, const struct nlattr *attr,
1022		  bool last)
1023{
1024	struct nlattr *actions;
1025	struct nlattr *sample_arg;
1026	int rem = nla_len(attr);
1027	const struct sample_arg *arg;
1028	bool clone_flow_key;
1029
1030	/* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
1031	sample_arg = nla_data(attr);
1032	arg = nla_data(sample_arg);
1033	actions = nla_next(sample_arg, &rem);
1034
1035	if ((arg->probability != U32_MAX) &&
1036	    (!arg->probability || get_random_u32() > arg->probability)) {
1037		if (last)
1038			consume_skb(skb);
1039		return 0;
1040	}
1041
1042	clone_flow_key = !arg->exec;
1043	return clone_execute(dp, skb, key, 0, actions, rem, last,
1044			     clone_flow_key);
1045}
1046
1047/* When 'last' is true, clone() should always consume the 'skb'.
1048 * Otherwise, clone() should keep 'skb' intact regardless what
1049 * actions are executed within clone().
1050 */
1051static int clone(struct datapath *dp, struct sk_buff *skb,
1052		 struct sw_flow_key *key, const struct nlattr *attr,
1053		 bool last)
1054{
1055	struct nlattr *actions;
1056	struct nlattr *clone_arg;
1057	int rem = nla_len(attr);
1058	bool dont_clone_flow_key;
1059
1060	/* The first action is always 'OVS_CLONE_ATTR_EXEC'. */
1061	clone_arg = nla_data(attr);
1062	dont_clone_flow_key = nla_get_u32(clone_arg);
1063	actions = nla_next(clone_arg, &rem);
1064
1065	return clone_execute(dp, skb, key, 0, actions, rem, last,
1066			     !dont_clone_flow_key);
1067}
1068
1069static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
1070			 const struct nlattr *attr)
1071{
1072	struct ovs_action_hash *hash_act = nla_data(attr);
1073	u32 hash = 0;
1074
1075	/* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
1076	hash = skb_get_hash(skb);
1077	hash = jhash_1word(hash, hash_act->hash_basis);
1078	if (!hash)
1079		hash = 0x1;
1080
1081	key->ovs_flow_hash = hash;
1082}
1083
1084static int execute_set_action(struct sk_buff *skb,
1085			      struct sw_flow_key *flow_key,
1086			      const struct nlattr *a)
1087{
1088	/* Only tunnel set execution is supported without a mask. */
1089	if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1090		struct ovs_tunnel_info *tun = nla_data(a);
1091
1092		skb_dst_drop(skb);
1093		dst_hold((struct dst_entry *)tun->tun_dst);
1094		skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
1095		return 0;
1096	}
1097
1098	return -EINVAL;
1099}
1100
1101/* Mask is at the midpoint of the data. */
1102#define get_mask(a, type) ((const type)nla_data(a) + 1)
1103
1104static int execute_masked_set_action(struct sk_buff *skb,
1105				     struct sw_flow_key *flow_key,
1106				     const struct nlattr *a)
1107{
1108	int err = 0;
1109
1110	switch (nla_type(a)) {
1111	case OVS_KEY_ATTR_PRIORITY:
1112		OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1113			       *get_mask(a, u32 *));
1114		flow_key->phy.priority = skb->priority;
1115		break;
1116
1117	case OVS_KEY_ATTR_SKB_MARK:
1118		OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1119		flow_key->phy.skb_mark = skb->mark;
1120		break;
1121
1122	case OVS_KEY_ATTR_TUNNEL_INFO:
1123		/* Masked data not supported for tunnel. */
1124		err = -EINVAL;
1125		break;
1126
1127	case OVS_KEY_ATTR_ETHERNET:
1128		err = set_eth_addr(skb, flow_key, nla_data(a),
1129				   get_mask(a, struct ovs_key_ethernet *));
1130		break;
1131
1132	case OVS_KEY_ATTR_NSH:
1133		err = set_nsh(skb, flow_key, a);
1134		break;
1135
1136	case OVS_KEY_ATTR_IPV4:
1137		err = set_ipv4(skb, flow_key, nla_data(a),
1138			       get_mask(a, struct ovs_key_ipv4 *));
1139		break;
1140
1141	case OVS_KEY_ATTR_IPV6:
1142		err = set_ipv6(skb, flow_key, nla_data(a),
1143			       get_mask(a, struct ovs_key_ipv6 *));
1144		break;
1145
1146	case OVS_KEY_ATTR_TCP:
1147		err = set_tcp(skb, flow_key, nla_data(a),
1148			      get_mask(a, struct ovs_key_tcp *));
1149		break;
1150
1151	case OVS_KEY_ATTR_UDP:
1152		err = set_udp(skb, flow_key, nla_data(a),
1153			      get_mask(a, struct ovs_key_udp *));
1154		break;
1155
1156	case OVS_KEY_ATTR_SCTP:
1157		err = set_sctp(skb, flow_key, nla_data(a),
1158			       get_mask(a, struct ovs_key_sctp *));
1159		break;
1160
1161	case OVS_KEY_ATTR_MPLS:
1162		err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1163								    __be32 *));
1164		break;
1165
1166	case OVS_KEY_ATTR_CT_STATE:
1167	case OVS_KEY_ATTR_CT_ZONE:
1168	case OVS_KEY_ATTR_CT_MARK:
1169	case OVS_KEY_ATTR_CT_LABELS:
1170	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1171	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1172		err = -EINVAL;
1173		break;
1174	}
1175
1176	return err;
1177}
1178
1179static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1180			  struct sw_flow_key *key,
1181			  const struct nlattr *a, bool last)
1182{
1183	u32 recirc_id;
1184
1185	if (!is_flow_key_valid(key)) {
1186		int err;
1187
1188		err = ovs_flow_key_update(skb, key);
1189		if (err)
1190			return err;
1191	}
1192	BUG_ON(!is_flow_key_valid(key));
1193
1194	recirc_id = nla_get_u32(a);
1195	return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
1196}
1197
1198static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
1199				 struct sw_flow_key *key,
1200				 const struct nlattr *attr, bool last)
1201{
1202	struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
1203	const struct nlattr *actions, *cpl_arg;
1204	int len, max_len, rem = nla_len(attr);
1205	const struct check_pkt_len_arg *arg;
1206	bool clone_flow_key;
1207
1208	/* The first netlink attribute in 'attr' is always
1209	 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
1210	 */
1211	cpl_arg = nla_data(attr);
1212	arg = nla_data(cpl_arg);
1213
1214	len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
1215	max_len = arg->pkt_len;
1216
1217	if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) ||
1218	    len <= max_len) {
1219		/* Second netlink attribute in 'attr' is always
1220		 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
1221		 */
1222		actions = nla_next(cpl_arg, &rem);
1223		clone_flow_key = !arg->exec_for_lesser_equal;
1224	} else {
1225		/* Third netlink attribute in 'attr' is always
1226		 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
1227		 */
1228		actions = nla_next(cpl_arg, &rem);
1229		actions = nla_next(actions, &rem);
1230		clone_flow_key = !arg->exec_for_greater;
1231	}
1232
1233	return clone_execute(dp, skb, key, 0, nla_data(actions),
1234			     nla_len(actions), last, clone_flow_key);
1235}
1236
1237static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key)
1238{
1239	int err;
1240
1241	if (skb->protocol == htons(ETH_P_IPV6)) {
1242		struct ipv6hdr *nh;
1243
1244		err = skb_ensure_writable(skb, skb_network_offset(skb) +
1245					  sizeof(*nh));
1246		if (unlikely(err))
1247			return err;
1248
1249		nh = ipv6_hdr(skb);
1250
1251		if (nh->hop_limit <= 1)
1252			return -EHOSTUNREACH;
1253
1254		key->ip.ttl = --nh->hop_limit;
1255	} else if (skb->protocol == htons(ETH_P_IP)) {
1256		struct iphdr *nh;
1257		u8 old_ttl;
1258
1259		err = skb_ensure_writable(skb, skb_network_offset(skb) +
1260					  sizeof(*nh));
1261		if (unlikely(err))
1262			return err;
1263
1264		nh = ip_hdr(skb);
1265		if (nh->ttl <= 1)
1266			return -EHOSTUNREACH;
1267
1268		old_ttl = nh->ttl--;
1269		csum_replace2(&nh->check, htons(old_ttl << 8),
1270			      htons(nh->ttl << 8));
1271		key->ip.ttl = nh->ttl;
1272	}
1273	return 0;
1274}
1275
1276/* Execute a list of actions against 'skb'. */
1277static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1278			      struct sw_flow_key *key,
1279			      const struct nlattr *attr, int len)
1280{
1281	const struct nlattr *a;
1282	int rem;
1283
1284	for (a = attr, rem = len; rem > 0;
1285	     a = nla_next(a, &rem)) {
1286		int err = 0;
1287
1288		if (trace_ovs_do_execute_action_enabled())
1289			trace_ovs_do_execute_action(dp, skb, key, a, rem);
1290
1291		switch (nla_type(a)) {
1292		case OVS_ACTION_ATTR_OUTPUT: {
1293			int port = nla_get_u32(a);
1294			struct sk_buff *clone;
1295
1296			/* Every output action needs a separate clone
1297			 * of 'skb', In case the output action is the
1298			 * last action, cloning can be avoided.
1299			 */
1300			if (nla_is_last(a, rem)) {
1301				do_output(dp, skb, port, key);
1302				/* 'skb' has been used for output.
1303				 */
1304				return 0;
1305			}
1306
1307			clone = skb_clone(skb, GFP_ATOMIC);
1308			if (clone)
1309				do_output(dp, clone, port, key);
1310			OVS_CB(skb)->cutlen = 0;
1311			break;
1312		}
1313
1314		case OVS_ACTION_ATTR_TRUNC: {
1315			struct ovs_action_trunc *trunc = nla_data(a);
1316
1317			if (skb->len > trunc->max_len)
1318				OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1319			break;
1320		}
1321
1322		case OVS_ACTION_ATTR_USERSPACE:
1323			output_userspace(dp, skb, key, a, attr,
1324						     len, OVS_CB(skb)->cutlen);
1325			OVS_CB(skb)->cutlen = 0;
1326			break;
1327
1328		case OVS_ACTION_ATTR_HASH:
1329			execute_hash(skb, key, a);
1330			break;
1331
1332		case OVS_ACTION_ATTR_PUSH_MPLS: {
1333			struct ovs_action_push_mpls *mpls = nla_data(a);
1334
1335			err = push_mpls(skb, key, mpls->mpls_lse,
1336					mpls->mpls_ethertype, skb->mac_len);
1337			break;
1338		}
1339		case OVS_ACTION_ATTR_ADD_MPLS: {
1340			struct ovs_action_add_mpls *mpls = nla_data(a);
1341			__u16 mac_len = 0;
1342
1343			if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK)
1344				mac_len = skb->mac_len;
1345
1346			err = push_mpls(skb, key, mpls->mpls_lse,
1347					mpls->mpls_ethertype, mac_len);
1348			break;
1349		}
1350		case OVS_ACTION_ATTR_POP_MPLS:
1351			err = pop_mpls(skb, key, nla_get_be16(a));
1352			break;
1353
1354		case OVS_ACTION_ATTR_PUSH_VLAN:
1355			err = push_vlan(skb, key, nla_data(a));
1356			break;
1357
1358		case OVS_ACTION_ATTR_POP_VLAN:
1359			err = pop_vlan(skb, key);
1360			break;
1361
1362		case OVS_ACTION_ATTR_RECIRC: {
1363			bool last = nla_is_last(a, rem);
1364
1365			err = execute_recirc(dp, skb, key, a, last);
1366			if (last) {
1367				/* If this is the last action, the skb has
1368				 * been consumed or freed.
1369				 * Return immediately.
1370				 */
1371				return err;
1372			}
1373			break;
1374		}
1375
1376		case OVS_ACTION_ATTR_SET:
1377			err = execute_set_action(skb, key, nla_data(a));
1378			break;
1379
1380		case OVS_ACTION_ATTR_SET_MASKED:
1381		case OVS_ACTION_ATTR_SET_TO_MASKED:
1382			err = execute_masked_set_action(skb, key, nla_data(a));
1383			break;
1384
1385		case OVS_ACTION_ATTR_SAMPLE: {
1386			bool last = nla_is_last(a, rem);
1387
1388			err = sample(dp, skb, key, a, last);
1389			if (last)
1390				return err;
1391
1392			break;
1393		}
1394
1395		case OVS_ACTION_ATTR_CT:
1396			if (!is_flow_key_valid(key)) {
1397				err = ovs_flow_key_update(skb, key);
1398				if (err)
1399					return err;
1400			}
1401
1402			err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1403					     nla_data(a));
1404
1405			/* Hide stolen IP fragments from user space. */
1406			if (err)
1407				return err == -EINPROGRESS ? 0 : err;
1408			break;
1409
1410		case OVS_ACTION_ATTR_CT_CLEAR:
1411			err = ovs_ct_clear(skb, key);
1412			break;
1413
1414		case OVS_ACTION_ATTR_PUSH_ETH:
1415			err = push_eth(skb, key, nla_data(a));
1416			break;
1417
1418		case OVS_ACTION_ATTR_POP_ETH:
1419			err = pop_eth(skb, key);
1420			break;
1421
1422		case OVS_ACTION_ATTR_PUSH_NSH: {
1423			u8 buffer[NSH_HDR_MAX_LEN];
1424			struct nshhdr *nh = (struct nshhdr *)buffer;
1425
1426			err = nsh_hdr_from_nlattr(nla_data(a), nh,
1427						  NSH_HDR_MAX_LEN);
1428			if (unlikely(err))
1429				break;
1430			err = push_nsh(skb, key, nh);
1431			break;
1432		}
1433
1434		case OVS_ACTION_ATTR_POP_NSH:
1435			err = pop_nsh(skb, key);
1436			break;
1437
1438		case OVS_ACTION_ATTR_METER:
1439			if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
1440				consume_skb(skb);
1441				return 0;
1442			}
1443			break;
1444
1445		case OVS_ACTION_ATTR_CLONE: {
1446			bool last = nla_is_last(a, rem);
1447
1448			err = clone(dp, skb, key, a, last);
1449			if (last)
1450				return err;
1451
1452			break;
1453		}
1454
1455		case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
1456			bool last = nla_is_last(a, rem);
1457
1458			err = execute_check_pkt_len(dp, skb, key, a, last);
1459			if (last)
1460				return err;
1461
1462			break;
1463		}
1464
1465		case OVS_ACTION_ATTR_DEC_TTL:
1466			err = execute_dec_ttl(skb, key);
1467			if (err == -EHOSTUNREACH)
1468				return dec_ttl_exception_handler(dp, skb,
1469								 key, a);
1470			break;
1471		}
1472
1473		if (unlikely(err)) {
1474			kfree_skb(skb);
1475			return err;
1476		}
1477	}
1478
1479	consume_skb(skb);
1480	return 0;
1481}
1482
1483/* Execute the actions on the clone of the packet. The effect of the
1484 * execution does not affect the original 'skb' nor the original 'key'.
1485 *
1486 * The execution may be deferred in case the actions can not be executed
1487 * immediately.
1488 */
1489static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1490			 struct sw_flow_key *key, u32 recirc_id,
1491			 const struct nlattr *actions, int len,
1492			 bool last, bool clone_flow_key)
1493{
1494	struct deferred_action *da;
1495	struct sw_flow_key *clone;
1496
1497	skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1498	if (!skb) {
1499		/* Out of memory, skip this action.
1500		 */
1501		return 0;
1502	}
1503
1504	/* When clone_flow_key is false, the 'key' will not be change
1505	 * by the actions, then the 'key' can be used directly.
1506	 * Otherwise, try to clone key from the next recursion level of
1507	 * 'flow_keys'. If clone is successful, execute the actions
1508	 * without deferring.
1509	 */
1510	clone = clone_flow_key ? clone_key(key) : key;
1511	if (clone) {
1512		int err = 0;
1513
1514		if (actions) { /* Sample action */
1515			if (clone_flow_key)
1516				__this_cpu_inc(exec_actions_level);
1517
1518			err = do_execute_actions(dp, skb, clone,
1519						 actions, len);
1520
1521			if (clone_flow_key)
1522				__this_cpu_dec(exec_actions_level);
1523		} else { /* Recirc action */
1524			clone->recirc_id = recirc_id;
1525			ovs_dp_process_packet(skb, clone);
1526		}
1527		return err;
1528	}
1529
1530	/* Out of 'flow_keys' space. Defer actions */
1531	da = add_deferred_actions(skb, key, actions, len);
1532	if (da) {
1533		if (!actions) { /* Recirc action */
1534			key = &da->pkt_key;
1535			key->recirc_id = recirc_id;
1536		}
1537	} else {
1538		/* Out of per CPU action FIFO space. Drop the 'skb' and
1539		 * log an error.
1540		 */
1541		kfree_skb(skb);
1542
1543		if (net_ratelimit()) {
1544			if (actions) { /* Sample action */
1545				pr_warn("%s: deferred action limit reached, drop sample action\n",
1546					ovs_dp_name(dp));
1547			} else {  /* Recirc action */
1548				pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n",
1549					ovs_dp_name(dp), recirc_id);
1550			}
1551		}
1552	}
1553	return 0;
1554}
1555
1556static void process_deferred_actions(struct datapath *dp)
1557{
1558	struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1559
1560	/* Do not touch the FIFO in case there is no deferred actions. */
1561	if (action_fifo_is_empty(fifo))
1562		return;
1563
1564	/* Finishing executing all deferred actions. */
1565	do {
1566		struct deferred_action *da = action_fifo_get(fifo);
1567		struct sk_buff *skb = da->skb;
1568		struct sw_flow_key *key = &da->pkt_key;
1569		const struct nlattr *actions = da->actions;
1570		int actions_len = da->actions_len;
1571
1572		if (actions)
1573			do_execute_actions(dp, skb, key, actions, actions_len);
1574		else
1575			ovs_dp_process_packet(skb, key);
1576	} while (!action_fifo_is_empty(fifo));
1577
1578	/* Reset FIFO for the next packet.  */
1579	action_fifo_init(fifo);
1580}
1581
1582/* Execute a list of actions against 'skb'. */
1583int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1584			const struct sw_flow_actions *acts,
1585			struct sw_flow_key *key)
1586{
1587	int err, level;
1588
1589	level = __this_cpu_inc_return(exec_actions_level);
1590	if (unlikely(level > OVS_RECURSION_LIMIT)) {
1591		net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1592				     ovs_dp_name(dp));
1593		kfree_skb(skb);
1594		err = -ENETDOWN;
1595		goto out;
1596	}
1597
1598	OVS_CB(skb)->acts_origlen = acts->orig_len;
1599	err = do_execute_actions(dp, skb, key,
1600				 acts->actions, acts->actions_len);
1601
1602	if (level == 1)
1603		process_deferred_actions(dp);
1604
1605out:
1606	__this_cpu_dec(exec_actions_level);
1607	return err;
1608}
1609
1610int action_fifos_init(void)
1611{
1612	action_fifos = alloc_percpu(struct action_fifo);
1613	if (!action_fifos)
1614		return -ENOMEM;
1615
1616	flow_keys = alloc_percpu(struct action_flow_keys);
1617	if (!flow_keys) {
1618		free_percpu(action_fifos);
1619		return -ENOMEM;
1620	}
1621
1622	return 0;
1623}
1624
1625void action_fifos_exit(void)
1626{
1627	free_percpu(action_fifos);
1628	free_percpu(flow_keys);
1629}