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v4.10.11
   1/*
   2 * Copyright (c) 2007-2014 Nicira, Inc.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of version 2 of the GNU General Public
   6 * License as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public License
  14 * along with this program; if not, write to the Free Software
  15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16 * 02110-1301, USA
  17 */
  18
  19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  20
  21#include <linux/skbuff.h>
  22#include <linux/in.h>
  23#include <linux/ip.h>
  24#include <linux/openvswitch.h>
  25#include <linux/netfilter_ipv6.h>
  26#include <linux/sctp.h>
  27#include <linux/tcp.h>
  28#include <linux/udp.h>
  29#include <linux/in6.h>
  30#include <linux/if_arp.h>
  31#include <linux/if_vlan.h>
  32
  33#include <net/dst.h>
  34#include <net/ip.h>
  35#include <net/ipv6.h>
  36#include <net/ip6_fib.h>
  37#include <net/checksum.h>
  38#include <net/dsfield.h>
  39#include <net/mpls.h>
  40#include <net/sctp/checksum.h>
  41
  42#include "datapath.h"
  43#include "flow.h"
  44#include "conntrack.h"
  45#include "vport.h"
  46
  47static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
  48			      struct sw_flow_key *key,
  49			      const struct nlattr *attr, int len);
  50
  51struct deferred_action {
  52	struct sk_buff *skb;
  53	const struct nlattr *actions;
 
  54
  55	/* Store pkt_key clone when creating deferred action. */
  56	struct sw_flow_key pkt_key;
  57};
  58
  59#define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
  60struct ovs_frag_data {
  61	unsigned long dst;
  62	struct vport *vport;
  63	struct ovs_skb_cb cb;
  64	__be16 inner_protocol;
  65	u16 network_offset;	/* valid only for MPLS */
  66	u16 vlan_tci;
  67	__be16 vlan_proto;
  68	unsigned int l2_len;
  69	u8 mac_proto;
  70	u8 l2_data[MAX_L2_LEN];
  71};
  72
  73static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
  74
  75#define DEFERRED_ACTION_FIFO_SIZE 10
  76#define OVS_RECURSION_LIMIT 5
  77#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
  78struct action_fifo {
  79	int head;
  80	int tail;
  81	/* Deferred action fifo queue storage. */
  82	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
  83};
  84
  85struct recirc_keys {
  86	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
  87};
  88
  89static struct action_fifo __percpu *action_fifos;
  90static struct recirc_keys __percpu *recirc_keys;
  91static DEFINE_PER_CPU(int, exec_actions_level);
  92
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  93static void action_fifo_init(struct action_fifo *fifo)
  94{
  95	fifo->head = 0;
  96	fifo->tail = 0;
  97}
  98
  99static bool action_fifo_is_empty(const struct action_fifo *fifo)
 100{
 101	return (fifo->head == fifo->tail);
 102}
 103
 104static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
 105{
 106	if (action_fifo_is_empty(fifo))
 107		return NULL;
 108
 109	return &fifo->fifo[fifo->tail++];
 110}
 111
 112static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
 113{
 114	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
 115		return NULL;
 116
 117	return &fifo->fifo[fifo->head++];
 118}
 119
 120/* Return true if fifo is not full */
 121static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
 122						    const struct sw_flow_key *key,
 123						    const struct nlattr *attr)
 
 124{
 125	struct action_fifo *fifo;
 126	struct deferred_action *da;
 127
 128	fifo = this_cpu_ptr(action_fifos);
 129	da = action_fifo_put(fifo);
 130	if (da) {
 131		da->skb = skb;
 132		da->actions = attr;
 
 133		da->pkt_key = *key;
 134	}
 135
 136	return da;
 137}
 138
 139static void invalidate_flow_key(struct sw_flow_key *key)
 140{
 141	key->mac_proto |= SW_FLOW_KEY_INVALID;
 142}
 143
 144static bool is_flow_key_valid(const struct sw_flow_key *key)
 145{
 146	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
 147}
 148
 
 
 
 
 
 
 149static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr,
 150			     __be16 ethertype)
 151{
 152	if (skb->ip_summed == CHECKSUM_COMPLETE) {
 153		__be16 diff[] = { ~(hdr->h_proto), ethertype };
 154
 155		skb->csum = ~csum_partial((char *)diff, sizeof(diff),
 156					~skb->csum);
 157	}
 158
 159	hdr->h_proto = ethertype;
 160}
 161
 162static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 163		     const struct ovs_action_push_mpls *mpls)
 164{
 165	struct mpls_shim_hdr *new_mpls_lse;
 166
 167	/* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
 168	if (skb->encapsulation)
 169		return -ENOTSUPP;
 170
 171	if (skb_cow_head(skb, MPLS_HLEN) < 0)
 172		return -ENOMEM;
 173
 174	if (!skb->inner_protocol) {
 175		skb_set_inner_network_header(skb, skb->mac_len);
 176		skb_set_inner_protocol(skb, skb->protocol);
 177	}
 178
 179	skb_push(skb, MPLS_HLEN);
 180	memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
 181		skb->mac_len);
 182	skb_reset_mac_header(skb);
 183	skb_set_network_header(skb, skb->mac_len);
 184
 185	new_mpls_lse = mpls_hdr(skb);
 186	new_mpls_lse->label_stack_entry = mpls->mpls_lse;
 187
 188	skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
 189
 190	if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET)
 191		update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
 192	skb->protocol = mpls->mpls_ethertype;
 193
 194	invalidate_flow_key(key);
 195	return 0;
 196}
 197
 198static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 199		    const __be16 ethertype)
 200{
 201	int err;
 202
 203	err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
 204	if (unlikely(err))
 205		return err;
 206
 207	skb_postpull_rcsum(skb, mpls_hdr(skb), MPLS_HLEN);
 208
 209	memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
 210		skb->mac_len);
 211
 212	__skb_pull(skb, MPLS_HLEN);
 213	skb_reset_mac_header(skb);
 214	skb_set_network_header(skb, skb->mac_len);
 215
 216	if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET) {
 217		struct ethhdr *hdr;
 218
 219		/* mpls_hdr() is used to locate the ethertype field correctly in the
 220		 * presence of VLAN tags.
 221		 */
 222		hdr = (struct ethhdr *)((void *)mpls_hdr(skb) - ETH_HLEN);
 223		update_ethertype(skb, hdr, ethertype);
 224	}
 225	if (eth_p_mpls(skb->protocol))
 226		skb->protocol = ethertype;
 227
 228	invalidate_flow_key(key);
 229	return 0;
 230}
 231
 232static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 233		    const __be32 *mpls_lse, const __be32 *mask)
 234{
 235	struct mpls_shim_hdr *stack;
 236	__be32 lse;
 237	int err;
 238
 239	err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
 240	if (unlikely(err))
 241		return err;
 242
 243	stack = mpls_hdr(skb);
 244	lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
 245	if (skb->ip_summed == CHECKSUM_COMPLETE) {
 246		__be32 diff[] = { ~(stack->label_stack_entry), lse };
 247
 248		skb->csum = ~csum_partial((char *)diff, sizeof(diff),
 249					  ~skb->csum);
 250	}
 251
 252	stack->label_stack_entry = lse;
 253	flow_key->mpls.top_lse = lse;
 254	return 0;
 255}
 256
 257static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 258{
 259	int err;
 260
 261	err = skb_vlan_pop(skb);
 262	if (skb_vlan_tag_present(skb)) {
 263		invalidate_flow_key(key);
 264	} else {
 265		key->eth.vlan.tci = 0;
 266		key->eth.vlan.tpid = 0;
 267	}
 268	return err;
 269}
 270
 271static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 272		     const struct ovs_action_push_vlan *vlan)
 273{
 274	if (skb_vlan_tag_present(skb)) {
 275		invalidate_flow_key(key);
 276	} else {
 277		key->eth.vlan.tci = vlan->vlan_tci;
 278		key->eth.vlan.tpid = vlan->vlan_tpid;
 279	}
 280	return skb_vlan_push(skb, vlan->vlan_tpid,
 281			     ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
 282}
 283
 284/* 'src' is already properly masked. */
 285static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 286{
 287	u16 *dst = (u16 *)dst_;
 288	const u16 *src = (const u16 *)src_;
 289	const u16 *mask = (const u16 *)mask_;
 290
 291	OVS_SET_MASKED(dst[0], src[0], mask[0]);
 292	OVS_SET_MASKED(dst[1], src[1], mask[1]);
 293	OVS_SET_MASKED(dst[2], src[2], mask[2]);
 294}
 295
 296static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 297			const struct ovs_key_ethernet *key,
 298			const struct ovs_key_ethernet *mask)
 299{
 300	int err;
 301
 302	err = skb_ensure_writable(skb, ETH_HLEN);
 303	if (unlikely(err))
 304		return err;
 305
 306	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 307
 308	ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 309			       mask->eth_src);
 310	ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 311			       mask->eth_dst);
 312
 313	skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 314
 315	ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 316	ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 317	return 0;
 318}
 319
 320/* pop_eth does not support VLAN packets as this action is never called
 321 * for them.
 322 */
 323static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
 324{
 325	skb_pull_rcsum(skb, ETH_HLEN);
 326	skb_reset_mac_header(skb);
 327	skb_reset_mac_len(skb);
 328
 329	/* safe right before invalidate_flow_key */
 330	key->mac_proto = MAC_PROTO_NONE;
 331	invalidate_flow_key(key);
 332	return 0;
 333}
 334
 335static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
 336		    const struct ovs_action_push_eth *ethh)
 337{
 338	struct ethhdr *hdr;
 339
 340	/* Add the new Ethernet header */
 341	if (skb_cow_head(skb, ETH_HLEN) < 0)
 342		return -ENOMEM;
 343
 344	skb_push(skb, ETH_HLEN);
 345	skb_reset_mac_header(skb);
 346	skb_reset_mac_len(skb);
 347
 348	hdr = eth_hdr(skb);
 349	ether_addr_copy(hdr->h_source, ethh->addresses.eth_src);
 350	ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst);
 351	hdr->h_proto = skb->protocol;
 352
 353	skb_postpush_rcsum(skb, hdr, ETH_HLEN);
 354
 355	/* safe right before invalidate_flow_key */
 356	key->mac_proto = MAC_PROTO_ETHERNET;
 357	invalidate_flow_key(key);
 358	return 0;
 359}
 360
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 361static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
 362				  __be32 addr, __be32 new_addr)
 363{
 364	int transport_len = skb->len - skb_transport_offset(skb);
 365
 366	if (nh->frag_off & htons(IP_OFFSET))
 367		return;
 368
 369	if (nh->protocol == IPPROTO_TCP) {
 370		if (likely(transport_len >= sizeof(struct tcphdr)))
 371			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 372						 addr, new_addr, true);
 373	} else if (nh->protocol == IPPROTO_UDP) {
 374		if (likely(transport_len >= sizeof(struct udphdr))) {
 375			struct udphdr *uh = udp_hdr(skb);
 376
 377			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 378				inet_proto_csum_replace4(&uh->check, skb,
 379							 addr, new_addr, true);
 380				if (!uh->check)
 381					uh->check = CSUM_MANGLED_0;
 382			}
 383		}
 384	}
 385}
 386
 387static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 388			__be32 *addr, __be32 new_addr)
 389{
 390	update_ip_l4_checksum(skb, nh, *addr, new_addr);
 391	csum_replace4(&nh->check, *addr, new_addr);
 392	skb_clear_hash(skb);
 393	*addr = new_addr;
 394}
 395
 396static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 397				 __be32 addr[4], const __be32 new_addr[4])
 398{
 399	int transport_len = skb->len - skb_transport_offset(skb);
 400
 401	if (l4_proto == NEXTHDR_TCP) {
 402		if (likely(transport_len >= sizeof(struct tcphdr)))
 403			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 404						  addr, new_addr, true);
 405	} else if (l4_proto == NEXTHDR_UDP) {
 406		if (likely(transport_len >= sizeof(struct udphdr))) {
 407			struct udphdr *uh = udp_hdr(skb);
 408
 409			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 410				inet_proto_csum_replace16(&uh->check, skb,
 411							  addr, new_addr, true);
 412				if (!uh->check)
 413					uh->check = CSUM_MANGLED_0;
 414			}
 415		}
 416	} else if (l4_proto == NEXTHDR_ICMP) {
 417		if (likely(transport_len >= sizeof(struct icmp6hdr)))
 418			inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 419						  skb, addr, new_addr, true);
 420	}
 421}
 422
 423static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 424			   const __be32 mask[4], __be32 masked[4])
 425{
 426	masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
 427	masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
 428	masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
 429	masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
 430}
 431
 432static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 433			  __be32 addr[4], const __be32 new_addr[4],
 434			  bool recalculate_csum)
 435{
 436	if (recalculate_csum)
 437		update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 438
 439	skb_clear_hash(skb);
 440	memcpy(addr, new_addr, sizeof(__be32[4]));
 441}
 442
 443static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
 444{
 445	/* Bits 21-24 are always unmasked, so this retains their values. */
 446	OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
 447	OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
 448	OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
 449}
 450
 451static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 452		       u8 mask)
 453{
 454	new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
 455
 456	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 457	nh->ttl = new_ttl;
 458}
 459
 460static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 461		    const struct ovs_key_ipv4 *key,
 462		    const struct ovs_key_ipv4 *mask)
 463{
 464	struct iphdr *nh;
 465	__be32 new_addr;
 466	int err;
 467
 468	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 469				  sizeof(struct iphdr));
 470	if (unlikely(err))
 471		return err;
 472
 473	nh = ip_hdr(skb);
 474
 475	/* Setting an IP addresses is typically only a side effect of
 476	 * matching on them in the current userspace implementation, so it
 477	 * makes sense to check if the value actually changed.
 478	 */
 479	if (mask->ipv4_src) {
 480		new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 481
 482		if (unlikely(new_addr != nh->saddr)) {
 483			set_ip_addr(skb, nh, &nh->saddr, new_addr);
 484			flow_key->ipv4.addr.src = new_addr;
 485		}
 486	}
 487	if (mask->ipv4_dst) {
 488		new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 489
 490		if (unlikely(new_addr != nh->daddr)) {
 491			set_ip_addr(skb, nh, &nh->daddr, new_addr);
 492			flow_key->ipv4.addr.dst = new_addr;
 493		}
 494	}
 495	if (mask->ipv4_tos) {
 496		ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 497		flow_key->ip.tos = nh->tos;
 498	}
 499	if (mask->ipv4_ttl) {
 500		set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 501		flow_key->ip.ttl = nh->ttl;
 502	}
 503
 504	return 0;
 505}
 506
 507static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 508{
 509	return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 510}
 511
 512static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 513		    const struct ovs_key_ipv6 *key,
 514		    const struct ovs_key_ipv6 *mask)
 515{
 516	struct ipv6hdr *nh;
 517	int err;
 518
 519	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 520				  sizeof(struct ipv6hdr));
 521	if (unlikely(err))
 522		return err;
 523
 524	nh = ipv6_hdr(skb);
 525
 526	/* Setting an IP addresses is typically only a side effect of
 527	 * matching on them in the current userspace implementation, so it
 528	 * makes sense to check if the value actually changed.
 529	 */
 530	if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 531		__be32 *saddr = (__be32 *)&nh->saddr;
 532		__be32 masked[4];
 533
 534		mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 535
 536		if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 537			set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
 538				      true);
 539			memcpy(&flow_key->ipv6.addr.src, masked,
 540			       sizeof(flow_key->ipv6.addr.src));
 541		}
 542	}
 543	if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 544		unsigned int offset = 0;
 545		int flags = IP6_FH_F_SKIP_RH;
 546		bool recalc_csum = true;
 547		__be32 *daddr = (__be32 *)&nh->daddr;
 548		__be32 masked[4];
 549
 550		mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 551
 552		if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 553			if (ipv6_ext_hdr(nh->nexthdr))
 554				recalc_csum = (ipv6_find_hdr(skb, &offset,
 555							     NEXTHDR_ROUTING,
 556							     NULL, &flags)
 557					       != NEXTHDR_ROUTING);
 558
 559			set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
 560				      recalc_csum);
 561			memcpy(&flow_key->ipv6.addr.dst, masked,
 562			       sizeof(flow_key->ipv6.addr.dst));
 563		}
 564	}
 565	if (mask->ipv6_tclass) {
 566		ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
 567		flow_key->ip.tos = ipv6_get_dsfield(nh);
 568	}
 569	if (mask->ipv6_label) {
 570		set_ipv6_fl(nh, ntohl(key->ipv6_label),
 571			    ntohl(mask->ipv6_label));
 572		flow_key->ipv6.label =
 573		    *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 574	}
 575	if (mask->ipv6_hlimit) {
 576		OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
 577			       mask->ipv6_hlimit);
 578		flow_key->ip.ttl = nh->hop_limit;
 579	}
 580	return 0;
 581}
 582
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 583/* Must follow skb_ensure_writable() since that can move the skb data. */
 584static void set_tp_port(struct sk_buff *skb, __be16 *port,
 585			__be16 new_port, __sum16 *check)
 586{
 587	inet_proto_csum_replace2(check, skb, *port, new_port, false);
 588	*port = new_port;
 589}
 590
 591static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 592		   const struct ovs_key_udp *key,
 593		   const struct ovs_key_udp *mask)
 594{
 595	struct udphdr *uh;
 596	__be16 src, dst;
 597	int err;
 598
 599	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 600				  sizeof(struct udphdr));
 601	if (unlikely(err))
 602		return err;
 603
 604	uh = udp_hdr(skb);
 605	/* Either of the masks is non-zero, so do not bother checking them. */
 606	src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
 607	dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 608
 609	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 610		if (likely(src != uh->source)) {
 611			set_tp_port(skb, &uh->source, src, &uh->check);
 612			flow_key->tp.src = src;
 613		}
 614		if (likely(dst != uh->dest)) {
 615			set_tp_port(skb, &uh->dest, dst, &uh->check);
 616			flow_key->tp.dst = dst;
 617		}
 618
 619		if (unlikely(!uh->check))
 620			uh->check = CSUM_MANGLED_0;
 621	} else {
 622		uh->source = src;
 623		uh->dest = dst;
 624		flow_key->tp.src = src;
 625		flow_key->tp.dst = dst;
 626	}
 627
 628	skb_clear_hash(skb);
 629
 630	return 0;
 631}
 632
 633static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 634		   const struct ovs_key_tcp *key,
 635		   const struct ovs_key_tcp *mask)
 636{
 637	struct tcphdr *th;
 638	__be16 src, dst;
 639	int err;
 640
 641	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 642				  sizeof(struct tcphdr));
 643	if (unlikely(err))
 644		return err;
 645
 646	th = tcp_hdr(skb);
 647	src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
 648	if (likely(src != th->source)) {
 649		set_tp_port(skb, &th->source, src, &th->check);
 650		flow_key->tp.src = src;
 651	}
 652	dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 653	if (likely(dst != th->dest)) {
 654		set_tp_port(skb, &th->dest, dst, &th->check);
 655		flow_key->tp.dst = dst;
 656	}
 657	skb_clear_hash(skb);
 658
 659	return 0;
 660}
 661
 662static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 663		    const struct ovs_key_sctp *key,
 664		    const struct ovs_key_sctp *mask)
 665{
 666	unsigned int sctphoff = skb_transport_offset(skb);
 667	struct sctphdr *sh;
 668	__le32 old_correct_csum, new_csum, old_csum;
 669	int err;
 670
 671	err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 672	if (unlikely(err))
 673		return err;
 674
 675	sh = sctp_hdr(skb);
 676	old_csum = sh->checksum;
 677	old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 678
 679	sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
 680	sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 681
 682	new_csum = sctp_compute_cksum(skb, sctphoff);
 683
 684	/* Carry any checksum errors through. */
 685	sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 686
 687	skb_clear_hash(skb);
 688	flow_key->tp.src = sh->source;
 689	flow_key->tp.dst = sh->dest;
 690
 691	return 0;
 692}
 693
 694static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 695{
 696	struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
 697	struct vport *vport = data->vport;
 698
 699	if (skb_cow_head(skb, data->l2_len) < 0) {
 700		kfree_skb(skb);
 701		return -ENOMEM;
 702	}
 703
 704	__skb_dst_copy(skb, data->dst);
 705	*OVS_CB(skb) = data->cb;
 706	skb->inner_protocol = data->inner_protocol;
 707	skb->vlan_tci = data->vlan_tci;
 708	skb->vlan_proto = data->vlan_proto;
 709
 710	/* Reconstruct the MAC header.  */
 711	skb_push(skb, data->l2_len);
 712	memcpy(skb->data, &data->l2_data, data->l2_len);
 713	skb_postpush_rcsum(skb, skb->data, data->l2_len);
 714	skb_reset_mac_header(skb);
 715
 716	if (eth_p_mpls(skb->protocol)) {
 717		skb->inner_network_header = skb->network_header;
 718		skb_set_network_header(skb, data->network_offset);
 719		skb_reset_mac_len(skb);
 720	}
 721
 722	ovs_vport_send(vport, skb, data->mac_proto);
 723	return 0;
 724}
 725
 726static unsigned int
 727ovs_dst_get_mtu(const struct dst_entry *dst)
 728{
 729	return dst->dev->mtu;
 730}
 731
 732static struct dst_ops ovs_dst_ops = {
 733	.family = AF_UNSPEC,
 734	.mtu = ovs_dst_get_mtu,
 735};
 736
 737/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 738 * ovs_vport_output(), which is called once per fragmented packet.
 739 */
 740static void prepare_frag(struct vport *vport, struct sk_buff *skb,
 741			 u16 orig_network_offset, u8 mac_proto)
 742{
 743	unsigned int hlen = skb_network_offset(skb);
 744	struct ovs_frag_data *data;
 745
 746	data = this_cpu_ptr(&ovs_frag_data_storage);
 747	data->dst = skb->_skb_refdst;
 748	data->vport = vport;
 749	data->cb = *OVS_CB(skb);
 750	data->inner_protocol = skb->inner_protocol;
 751	data->network_offset = orig_network_offset;
 752	data->vlan_tci = skb->vlan_tci;
 753	data->vlan_proto = skb->vlan_proto;
 754	data->mac_proto = mac_proto;
 755	data->l2_len = hlen;
 756	memcpy(&data->l2_data, skb->data, hlen);
 757
 758	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 759	skb_pull(skb, hlen);
 760}
 761
 762static void ovs_fragment(struct net *net, struct vport *vport,
 763			 struct sk_buff *skb, u16 mru,
 764			 struct sw_flow_key *key)
 765{
 766	u16 orig_network_offset = 0;
 767
 768	if (eth_p_mpls(skb->protocol)) {
 769		orig_network_offset = skb_network_offset(skb);
 770		skb->network_header = skb->inner_network_header;
 771	}
 772
 773	if (skb_network_offset(skb) > MAX_L2_LEN) {
 774		OVS_NLERR(1, "L2 header too long to fragment");
 775		goto err;
 776	}
 777
 778	if (key->eth.type == htons(ETH_P_IP)) {
 779		struct dst_entry ovs_dst;
 780		unsigned long orig_dst;
 781
 782		prepare_frag(vport, skb, orig_network_offset,
 783			     ovs_key_mac_proto(key));
 784		dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1,
 785			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 786		ovs_dst.dev = vport->dev;
 787
 788		orig_dst = skb->_skb_refdst;
 789		skb_dst_set_noref(skb, &ovs_dst);
 790		IPCB(skb)->frag_max_size = mru;
 791
 792		ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
 793		refdst_drop(orig_dst);
 794	} else if (key->eth.type == htons(ETH_P_IPV6)) {
 795		const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
 796		unsigned long orig_dst;
 797		struct rt6_info ovs_rt;
 798
 799		if (!v6ops) {
 800			goto err;
 801		}
 802
 803		prepare_frag(vport, skb, orig_network_offset,
 804			     ovs_key_mac_proto(key));
 805		memset(&ovs_rt, 0, sizeof(ovs_rt));
 806		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 807			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 808		ovs_rt.dst.dev = vport->dev;
 809
 810		orig_dst = skb->_skb_refdst;
 811		skb_dst_set_noref(skb, &ovs_rt.dst);
 812		IP6CB(skb)->frag_max_size = mru;
 813
 814		v6ops->fragment(net, skb->sk, skb, ovs_vport_output);
 815		refdst_drop(orig_dst);
 816	} else {
 817		WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
 818			  ovs_vport_name(vport), ntohs(key->eth.type), mru,
 819			  vport->dev->mtu);
 820		goto err;
 821	}
 822
 823	return;
 824err:
 825	kfree_skb(skb);
 826}
 827
 828static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
 829		      struct sw_flow_key *key)
 830{
 831	struct vport *vport = ovs_vport_rcu(dp, out_port);
 832
 833	if (likely(vport)) {
 834		u16 mru = OVS_CB(skb)->mru;
 835		u32 cutlen = OVS_CB(skb)->cutlen;
 836
 837		if (unlikely(cutlen > 0)) {
 838			if (skb->len - cutlen > ovs_mac_header_len(key))
 839				pskb_trim(skb, skb->len - cutlen);
 840			else
 841				pskb_trim(skb, ovs_mac_header_len(key));
 842		}
 843
 844		if (likely(!mru ||
 845		           (skb->len <= mru + vport->dev->hard_header_len))) {
 846			ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
 847		} else if (mru <= vport->dev->mtu) {
 848			struct net *net = read_pnet(&dp->net);
 849
 850			ovs_fragment(net, vport, skb, mru, key);
 851		} else {
 852			kfree_skb(skb);
 853		}
 854	} else {
 855		kfree_skb(skb);
 856	}
 857}
 858
 859static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 860			    struct sw_flow_key *key, const struct nlattr *attr,
 861			    const struct nlattr *actions, int actions_len,
 862			    uint32_t cutlen)
 863{
 864	struct dp_upcall_info upcall;
 865	const struct nlattr *a;
 866	int rem;
 867
 868	memset(&upcall, 0, sizeof(upcall));
 869	upcall.cmd = OVS_PACKET_CMD_ACTION;
 870	upcall.mru = OVS_CB(skb)->mru;
 871
 872	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 873		 a = nla_next(a, &rem)) {
 874		switch (nla_type(a)) {
 875		case OVS_USERSPACE_ATTR_USERDATA:
 876			upcall.userdata = a;
 877			break;
 878
 879		case OVS_USERSPACE_ATTR_PID:
 880			upcall.portid = nla_get_u32(a);
 881			break;
 882
 883		case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
 884			/* Get out tunnel info. */
 885			struct vport *vport;
 886
 887			vport = ovs_vport_rcu(dp, nla_get_u32(a));
 888			if (vport) {
 889				int err;
 890
 891				err = dev_fill_metadata_dst(vport->dev, skb);
 892				if (!err)
 893					upcall.egress_tun_info = skb_tunnel_info(skb);
 894			}
 895
 896			break;
 897		}
 898
 899		case OVS_USERSPACE_ATTR_ACTIONS: {
 900			/* Include actions. */
 901			upcall.actions = actions;
 902			upcall.actions_len = actions_len;
 903			break;
 904		}
 905
 906		} /* End of switch. */
 907	}
 908
 909	return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
 910}
 911
 
 
 
 
 912static int sample(struct datapath *dp, struct sk_buff *skb,
 913		  struct sw_flow_key *key, const struct nlattr *attr,
 914		  const struct nlattr *actions, int actions_len)
 915{
 916	const struct nlattr *acts_list = NULL;
 917	const struct nlattr *a;
 918	int rem;
 919	u32 cutlen = 0;
 920
 921	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 922		 a = nla_next(a, &rem)) {
 923		u32 probability;
 924
 925		switch (nla_type(a)) {
 926		case OVS_SAMPLE_ATTR_PROBABILITY:
 927			probability = nla_get_u32(a);
 928			if (!probability || prandom_u32() > probability)
 929				return 0;
 930			break;
 931
 932		case OVS_SAMPLE_ATTR_ACTIONS:
 933			acts_list = a;
 934			break;
 935		}
 936	}
 937
 938	rem = nla_len(acts_list);
 939	a = nla_data(acts_list);
 940
 941	/* Actions list is empty, do nothing */
 942	if (unlikely(!rem))
 943		return 0;
 944
 945	/* The only known usage of sample action is having a single user-space
 946	 * action, or having a truncate action followed by a single user-space
 947	 * action. Treat this usage as a special case.
 948	 * The output_userspace() should clone the skb to be sent to the
 949	 * user space. This skb will be consumed by its caller.
 950	 */
 951	if (unlikely(nla_type(a) == OVS_ACTION_ATTR_TRUNC)) {
 952		struct ovs_action_trunc *trunc = nla_data(a);
 953
 954		if (skb->len > trunc->max_len)
 955			cutlen = skb->len - trunc->max_len;
 956
 957		a = nla_next(a, &rem);
 958	}
 959
 960	if (likely(nla_type(a) == OVS_ACTION_ATTR_USERSPACE &&
 961		   nla_is_last(a, rem)))
 962		return output_userspace(dp, skb, key, a, actions,
 963					actions_len, cutlen);
 964
 965	skb = skb_clone(skb, GFP_ATOMIC);
 966	if (!skb)
 967		/* Skip the sample action when out of memory. */
 968		return 0;
 969
 970	if (!add_deferred_actions(skb, key, a)) {
 971		if (net_ratelimit())
 972			pr_warn("%s: deferred actions limit reached, dropping sample action\n",
 973				ovs_dp_name(dp));
 974
 975		kfree_skb(skb);
 976	}
 977	return 0;
 978}
 979
 980static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
 981			 const struct nlattr *attr)
 982{
 983	struct ovs_action_hash *hash_act = nla_data(attr);
 984	u32 hash = 0;
 985
 986	/* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
 987	hash = skb_get_hash(skb);
 988	hash = jhash_1word(hash, hash_act->hash_basis);
 989	if (!hash)
 990		hash = 0x1;
 991
 992	key->ovs_flow_hash = hash;
 993}
 994
 995static int execute_set_action(struct sk_buff *skb,
 996			      struct sw_flow_key *flow_key,
 997			      const struct nlattr *a)
 998{
 999	/* Only tunnel set execution is supported without a mask. */
1000	if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1001		struct ovs_tunnel_info *tun = nla_data(a);
1002
1003		skb_dst_drop(skb);
1004		dst_hold((struct dst_entry *)tun->tun_dst);
1005		skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
1006		return 0;
1007	}
1008
1009	return -EINVAL;
1010}
1011
1012/* Mask is at the midpoint of the data. */
1013#define get_mask(a, type) ((const type)nla_data(a) + 1)
1014
1015static int execute_masked_set_action(struct sk_buff *skb,
1016				     struct sw_flow_key *flow_key,
1017				     const struct nlattr *a)
1018{
1019	int err = 0;
1020
1021	switch (nla_type(a)) {
1022	case OVS_KEY_ATTR_PRIORITY:
1023		OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1024			       *get_mask(a, u32 *));
1025		flow_key->phy.priority = skb->priority;
1026		break;
1027
1028	case OVS_KEY_ATTR_SKB_MARK:
1029		OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1030		flow_key->phy.skb_mark = skb->mark;
1031		break;
1032
1033	case OVS_KEY_ATTR_TUNNEL_INFO:
1034		/* Masked data not supported for tunnel. */
1035		err = -EINVAL;
1036		break;
1037
1038	case OVS_KEY_ATTR_ETHERNET:
1039		err = set_eth_addr(skb, flow_key, nla_data(a),
1040				   get_mask(a, struct ovs_key_ethernet *));
1041		break;
1042
 
 
 
 
1043	case OVS_KEY_ATTR_IPV4:
1044		err = set_ipv4(skb, flow_key, nla_data(a),
1045			       get_mask(a, struct ovs_key_ipv4 *));
1046		break;
1047
1048	case OVS_KEY_ATTR_IPV6:
1049		err = set_ipv6(skb, flow_key, nla_data(a),
1050			       get_mask(a, struct ovs_key_ipv6 *));
1051		break;
1052
1053	case OVS_KEY_ATTR_TCP:
1054		err = set_tcp(skb, flow_key, nla_data(a),
1055			      get_mask(a, struct ovs_key_tcp *));
1056		break;
1057
1058	case OVS_KEY_ATTR_UDP:
1059		err = set_udp(skb, flow_key, nla_data(a),
1060			      get_mask(a, struct ovs_key_udp *));
1061		break;
1062
1063	case OVS_KEY_ATTR_SCTP:
1064		err = set_sctp(skb, flow_key, nla_data(a),
1065			       get_mask(a, struct ovs_key_sctp *));
1066		break;
1067
1068	case OVS_KEY_ATTR_MPLS:
1069		err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1070								    __be32 *));
1071		break;
1072
1073	case OVS_KEY_ATTR_CT_STATE:
1074	case OVS_KEY_ATTR_CT_ZONE:
1075	case OVS_KEY_ATTR_CT_MARK:
1076	case OVS_KEY_ATTR_CT_LABELS:
 
 
1077		err = -EINVAL;
1078		break;
1079	}
1080
1081	return err;
1082}
1083
1084static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1085			  struct sw_flow_key *key,
1086			  const struct nlattr *a, int rem)
1087{
1088	struct deferred_action *da;
1089	int level;
1090
1091	if (!is_flow_key_valid(key)) {
1092		int err;
1093
1094		err = ovs_flow_key_update(skb, key);
1095		if (err)
1096			return err;
1097	}
1098	BUG_ON(!is_flow_key_valid(key));
1099
1100	if (!nla_is_last(a, rem)) {
1101		/* Recirc action is the not the last action
1102		 * of the action list, need to clone the skb.
1103		 */
1104		skb = skb_clone(skb, GFP_ATOMIC);
1105
1106		/* Skip the recirc action when out of memory, but
1107		 * continue on with the rest of the action list.
1108		 */
1109		if (!skb)
1110			return 0;
1111	}
1112
1113	level = this_cpu_read(exec_actions_level);
1114	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
1115		struct recirc_keys *rks = this_cpu_ptr(recirc_keys);
1116		struct sw_flow_key *recirc_key = &rks->key[level - 1];
1117
1118		*recirc_key = *key;
1119		recirc_key->recirc_id = nla_get_u32(a);
1120		ovs_dp_process_packet(skb, recirc_key);
1121
1122		return 0;
1123	}
1124
1125	da = add_deferred_actions(skb, key, NULL);
1126	if (da) {
1127		da->pkt_key.recirc_id = nla_get_u32(a);
1128	} else {
1129		kfree_skb(skb);
1130
1131		if (net_ratelimit())
1132			pr_warn("%s: deferred action limit reached, drop recirc action\n",
1133				ovs_dp_name(dp));
1134	}
1135
1136	return 0;
1137}
1138
1139/* Execute a list of actions against 'skb'. */
1140static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1141			      struct sw_flow_key *key,
1142			      const struct nlattr *attr, int len)
1143{
1144	/* Every output action needs a separate clone of 'skb', but the common
1145	 * case is just a single output action, so that doing a clone and
1146	 * then freeing the original skbuff is wasteful.  So the following code
1147	 * is slightly obscure just to avoid that.
1148	 */
1149	int prev_port = -1;
1150	const struct nlattr *a;
1151	int rem;
1152
1153	for (a = attr, rem = len; rem > 0;
1154	     a = nla_next(a, &rem)) {
1155		int err = 0;
1156
1157		if (unlikely(prev_port != -1)) {
1158			struct sk_buff *out_skb = skb_clone(skb, GFP_ATOMIC);
1159
1160			if (out_skb)
1161				do_output(dp, out_skb, prev_port, key);
 
 
 
 
 
 
 
 
 
 
1162
 
 
 
1163			OVS_CB(skb)->cutlen = 0;
1164			prev_port = -1;
1165		}
1166
1167		switch (nla_type(a)) {
1168		case OVS_ACTION_ATTR_OUTPUT:
1169			prev_port = nla_get_u32(a);
1170			break;
 
1171
1172		case OVS_ACTION_ATTR_TRUNC: {
1173			struct ovs_action_trunc *trunc = nla_data(a);
1174
1175			if (skb->len > trunc->max_len)
1176				OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1177			break;
1178		}
1179
1180		case OVS_ACTION_ATTR_USERSPACE:
1181			output_userspace(dp, skb, key, a, attr,
1182						     len, OVS_CB(skb)->cutlen);
1183			OVS_CB(skb)->cutlen = 0;
1184			break;
1185
1186		case OVS_ACTION_ATTR_HASH:
1187			execute_hash(skb, key, a);
1188			break;
1189
1190		case OVS_ACTION_ATTR_PUSH_MPLS:
1191			err = push_mpls(skb, key, nla_data(a));
1192			break;
1193
1194		case OVS_ACTION_ATTR_POP_MPLS:
1195			err = pop_mpls(skb, key, nla_get_be16(a));
1196			break;
1197
1198		case OVS_ACTION_ATTR_PUSH_VLAN:
1199			err = push_vlan(skb, key, nla_data(a));
1200			break;
1201
1202		case OVS_ACTION_ATTR_POP_VLAN:
1203			err = pop_vlan(skb, key);
1204			break;
1205
1206		case OVS_ACTION_ATTR_RECIRC:
1207			err = execute_recirc(dp, skb, key, a, rem);
1208			if (nla_is_last(a, rem)) {
 
 
1209				/* If this is the last action, the skb has
1210				 * been consumed or freed.
1211				 * Return immediately.
1212				 */
1213				return err;
1214			}
1215			break;
 
1216
1217		case OVS_ACTION_ATTR_SET:
1218			err = execute_set_action(skb, key, nla_data(a));
1219			break;
1220
1221		case OVS_ACTION_ATTR_SET_MASKED:
1222		case OVS_ACTION_ATTR_SET_TO_MASKED:
1223			err = execute_masked_set_action(skb, key, nla_data(a));
1224			break;
1225
1226		case OVS_ACTION_ATTR_SAMPLE:
1227			err = sample(dp, skb, key, a, attr, len);
 
 
 
 
 
1228			break;
 
1229
1230		case OVS_ACTION_ATTR_CT:
1231			if (!is_flow_key_valid(key)) {
1232				err = ovs_flow_key_update(skb, key);
1233				if (err)
1234					return err;
1235			}
1236
1237			err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1238					     nla_data(a));
1239
1240			/* Hide stolen IP fragments from user space. */
1241			if (err)
1242				return err == -EINPROGRESS ? 0 : err;
1243			break;
1244
 
 
 
 
1245		case OVS_ACTION_ATTR_PUSH_ETH:
1246			err = push_eth(skb, key, nla_data(a));
1247			break;
1248
1249		case OVS_ACTION_ATTR_POP_ETH:
1250			err = pop_eth(skb, key);
1251			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1252		}
1253
1254		if (unlikely(err)) {
1255			kfree_skb(skb);
1256			return err;
1257		}
1258	}
1259
1260	if (prev_port != -1)
1261		do_output(dp, skb, prev_port, key);
1262	else
1263		consume_skb(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
1264
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1265	return 0;
1266}
1267
1268static void process_deferred_actions(struct datapath *dp)
1269{
1270	struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1271
1272	/* Do not touch the FIFO in case there is no deferred actions. */
1273	if (action_fifo_is_empty(fifo))
1274		return;
1275
1276	/* Finishing executing all deferred actions. */
1277	do {
1278		struct deferred_action *da = action_fifo_get(fifo);
1279		struct sk_buff *skb = da->skb;
1280		struct sw_flow_key *key = &da->pkt_key;
1281		const struct nlattr *actions = da->actions;
 
1282
1283		if (actions)
1284			do_execute_actions(dp, skb, key, actions,
1285					   nla_len(actions));
1286		else
1287			ovs_dp_process_packet(skb, key);
1288	} while (!action_fifo_is_empty(fifo));
1289
1290	/* Reset FIFO for the next packet.  */
1291	action_fifo_init(fifo);
1292}
1293
1294/* Execute a list of actions against 'skb'. */
1295int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1296			const struct sw_flow_actions *acts,
1297			struct sw_flow_key *key)
1298{
1299	int err, level;
1300
1301	level = __this_cpu_inc_return(exec_actions_level);
1302	if (unlikely(level > OVS_RECURSION_LIMIT)) {
1303		net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1304				     ovs_dp_name(dp));
1305		kfree_skb(skb);
1306		err = -ENETDOWN;
1307		goto out;
1308	}
1309
 
1310	err = do_execute_actions(dp, skb, key,
1311				 acts->actions, acts->actions_len);
1312
1313	if (level == 1)
1314		process_deferred_actions(dp);
1315
1316out:
1317	__this_cpu_dec(exec_actions_level);
1318	return err;
1319}
1320
1321int action_fifos_init(void)
1322{
1323	action_fifos = alloc_percpu(struct action_fifo);
1324	if (!action_fifos)
1325		return -ENOMEM;
1326
1327	recirc_keys = alloc_percpu(struct recirc_keys);
1328	if (!recirc_keys) {
1329		free_percpu(action_fifos);
1330		return -ENOMEM;
1331	}
1332
1333	return 0;
1334}
1335
1336void action_fifos_exit(void)
1337{
1338	free_percpu(action_fifos);
1339	free_percpu(recirc_keys);
1340}
v4.17
   1/*
   2 * Copyright (c) 2007-2017 Nicira, Inc.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of version 2 of the GNU General Public
   6 * License as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public License
  14 * along with this program; if not, write to the Free Software
  15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16 * 02110-1301, USA
  17 */
  18
  19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  20
  21#include <linux/skbuff.h>
  22#include <linux/in.h>
  23#include <linux/ip.h>
  24#include <linux/openvswitch.h>
  25#include <linux/netfilter_ipv6.h>
  26#include <linux/sctp.h>
  27#include <linux/tcp.h>
  28#include <linux/udp.h>
  29#include <linux/in6.h>
  30#include <linux/if_arp.h>
  31#include <linux/if_vlan.h>
  32
  33#include <net/dst.h>
  34#include <net/ip.h>
  35#include <net/ipv6.h>
  36#include <net/ip6_fib.h>
  37#include <net/checksum.h>
  38#include <net/dsfield.h>
  39#include <net/mpls.h>
  40#include <net/sctp/checksum.h>
  41
  42#include "datapath.h"
  43#include "flow.h"
  44#include "conntrack.h"
  45#include "vport.h"
  46#include "flow_netlink.h"
 
 
 
  47
  48struct deferred_action {
  49	struct sk_buff *skb;
  50	const struct nlattr *actions;
  51	int actions_len;
  52
  53	/* Store pkt_key clone when creating deferred action. */
  54	struct sw_flow_key pkt_key;
  55};
  56
  57#define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
  58struct ovs_frag_data {
  59	unsigned long dst;
  60	struct vport *vport;
  61	struct ovs_skb_cb cb;
  62	__be16 inner_protocol;
  63	u16 network_offset;	/* valid only for MPLS */
  64	u16 vlan_tci;
  65	__be16 vlan_proto;
  66	unsigned int l2_len;
  67	u8 mac_proto;
  68	u8 l2_data[MAX_L2_LEN];
  69};
  70
  71static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
  72
  73#define DEFERRED_ACTION_FIFO_SIZE 10
  74#define OVS_RECURSION_LIMIT 5
  75#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
  76struct action_fifo {
  77	int head;
  78	int tail;
  79	/* Deferred action fifo queue storage. */
  80	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
  81};
  82
  83struct action_flow_keys {
  84	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
  85};
  86
  87static struct action_fifo __percpu *action_fifos;
  88static struct action_flow_keys __percpu *flow_keys;
  89static DEFINE_PER_CPU(int, exec_actions_level);
  90
  91/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
  92 * space. Return NULL if out of key spaces.
  93 */
  94static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
  95{
  96	struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
  97	int level = this_cpu_read(exec_actions_level);
  98	struct sw_flow_key *key = NULL;
  99
 100	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
 101		key = &keys->key[level - 1];
 102		*key = *key_;
 103	}
 104
 105	return key;
 106}
 107
 108static void action_fifo_init(struct action_fifo *fifo)
 109{
 110	fifo->head = 0;
 111	fifo->tail = 0;
 112}
 113
 114static bool action_fifo_is_empty(const struct action_fifo *fifo)
 115{
 116	return (fifo->head == fifo->tail);
 117}
 118
 119static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
 120{
 121	if (action_fifo_is_empty(fifo))
 122		return NULL;
 123
 124	return &fifo->fifo[fifo->tail++];
 125}
 126
 127static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
 128{
 129	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
 130		return NULL;
 131
 132	return &fifo->fifo[fifo->head++];
 133}
 134
 135/* Return true if fifo is not full */
 136static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
 137				    const struct sw_flow_key *key,
 138				    const struct nlattr *actions,
 139				    const int actions_len)
 140{
 141	struct action_fifo *fifo;
 142	struct deferred_action *da;
 143
 144	fifo = this_cpu_ptr(action_fifos);
 145	da = action_fifo_put(fifo);
 146	if (da) {
 147		da->skb = skb;
 148		da->actions = actions;
 149		da->actions_len = actions_len;
 150		da->pkt_key = *key;
 151	}
 152
 153	return da;
 154}
 155
 156static void invalidate_flow_key(struct sw_flow_key *key)
 157{
 158	key->mac_proto |= SW_FLOW_KEY_INVALID;
 159}
 160
 161static bool is_flow_key_valid(const struct sw_flow_key *key)
 162{
 163	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
 164}
 165
 166static int clone_execute(struct datapath *dp, struct sk_buff *skb,
 167			 struct sw_flow_key *key,
 168			 u32 recirc_id,
 169			 const struct nlattr *actions, int len,
 170			 bool last, bool clone_flow_key);
 171
 172static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr,
 173			     __be16 ethertype)
 174{
 175	if (skb->ip_summed == CHECKSUM_COMPLETE) {
 176		__be16 diff[] = { ~(hdr->h_proto), ethertype };
 177
 178		skb->csum = ~csum_partial((char *)diff, sizeof(diff),
 179					~skb->csum);
 180	}
 181
 182	hdr->h_proto = ethertype;
 183}
 184
 185static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 186		     const struct ovs_action_push_mpls *mpls)
 187{
 188	struct mpls_shim_hdr *new_mpls_lse;
 189
 190	/* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
 191	if (skb->encapsulation)
 192		return -ENOTSUPP;
 193
 194	if (skb_cow_head(skb, MPLS_HLEN) < 0)
 195		return -ENOMEM;
 196
 197	if (!skb->inner_protocol) {
 198		skb_set_inner_network_header(skb, skb->mac_len);
 199		skb_set_inner_protocol(skb, skb->protocol);
 200	}
 201
 202	skb_push(skb, MPLS_HLEN);
 203	memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
 204		skb->mac_len);
 205	skb_reset_mac_header(skb);
 206	skb_set_network_header(skb, skb->mac_len);
 207
 208	new_mpls_lse = mpls_hdr(skb);
 209	new_mpls_lse->label_stack_entry = mpls->mpls_lse;
 210
 211	skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
 212
 213	if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET)
 214		update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
 215	skb->protocol = mpls->mpls_ethertype;
 216
 217	invalidate_flow_key(key);
 218	return 0;
 219}
 220
 221static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 222		    const __be16 ethertype)
 223{
 224	int err;
 225
 226	err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
 227	if (unlikely(err))
 228		return err;
 229
 230	skb_postpull_rcsum(skb, mpls_hdr(skb), MPLS_HLEN);
 231
 232	memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
 233		skb->mac_len);
 234
 235	__skb_pull(skb, MPLS_HLEN);
 236	skb_reset_mac_header(skb);
 237	skb_set_network_header(skb, skb->mac_len);
 238
 239	if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET) {
 240		struct ethhdr *hdr;
 241
 242		/* mpls_hdr() is used to locate the ethertype field correctly in the
 243		 * presence of VLAN tags.
 244		 */
 245		hdr = (struct ethhdr *)((void *)mpls_hdr(skb) - ETH_HLEN);
 246		update_ethertype(skb, hdr, ethertype);
 247	}
 248	if (eth_p_mpls(skb->protocol))
 249		skb->protocol = ethertype;
 250
 251	invalidate_flow_key(key);
 252	return 0;
 253}
 254
 255static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 256		    const __be32 *mpls_lse, const __be32 *mask)
 257{
 258	struct mpls_shim_hdr *stack;
 259	__be32 lse;
 260	int err;
 261
 262	err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
 263	if (unlikely(err))
 264		return err;
 265
 266	stack = mpls_hdr(skb);
 267	lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
 268	if (skb->ip_summed == CHECKSUM_COMPLETE) {
 269		__be32 diff[] = { ~(stack->label_stack_entry), lse };
 270
 271		skb->csum = ~csum_partial((char *)diff, sizeof(diff),
 272					  ~skb->csum);
 273	}
 274
 275	stack->label_stack_entry = lse;
 276	flow_key->mpls.top_lse = lse;
 277	return 0;
 278}
 279
 280static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 281{
 282	int err;
 283
 284	err = skb_vlan_pop(skb);
 285	if (skb_vlan_tag_present(skb)) {
 286		invalidate_flow_key(key);
 287	} else {
 288		key->eth.vlan.tci = 0;
 289		key->eth.vlan.tpid = 0;
 290	}
 291	return err;
 292}
 293
 294static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 295		     const struct ovs_action_push_vlan *vlan)
 296{
 297	if (skb_vlan_tag_present(skb)) {
 298		invalidate_flow_key(key);
 299	} else {
 300		key->eth.vlan.tci = vlan->vlan_tci;
 301		key->eth.vlan.tpid = vlan->vlan_tpid;
 302	}
 303	return skb_vlan_push(skb, vlan->vlan_tpid,
 304			     ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
 305}
 306
 307/* 'src' is already properly masked. */
 308static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 309{
 310	u16 *dst = (u16 *)dst_;
 311	const u16 *src = (const u16 *)src_;
 312	const u16 *mask = (const u16 *)mask_;
 313
 314	OVS_SET_MASKED(dst[0], src[0], mask[0]);
 315	OVS_SET_MASKED(dst[1], src[1], mask[1]);
 316	OVS_SET_MASKED(dst[2], src[2], mask[2]);
 317}
 318
 319static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 320			const struct ovs_key_ethernet *key,
 321			const struct ovs_key_ethernet *mask)
 322{
 323	int err;
 324
 325	err = skb_ensure_writable(skb, ETH_HLEN);
 326	if (unlikely(err))
 327		return err;
 328
 329	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 330
 331	ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 332			       mask->eth_src);
 333	ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 334			       mask->eth_dst);
 335
 336	skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 337
 338	ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 339	ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 340	return 0;
 341}
 342
 343/* pop_eth does not support VLAN packets as this action is never called
 344 * for them.
 345 */
 346static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
 347{
 348	skb_pull_rcsum(skb, ETH_HLEN);
 349	skb_reset_mac_header(skb);
 350	skb_reset_mac_len(skb);
 351
 352	/* safe right before invalidate_flow_key */
 353	key->mac_proto = MAC_PROTO_NONE;
 354	invalidate_flow_key(key);
 355	return 0;
 356}
 357
 358static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
 359		    const struct ovs_action_push_eth *ethh)
 360{
 361	struct ethhdr *hdr;
 362
 363	/* Add the new Ethernet header */
 364	if (skb_cow_head(skb, ETH_HLEN) < 0)
 365		return -ENOMEM;
 366
 367	skb_push(skb, ETH_HLEN);
 368	skb_reset_mac_header(skb);
 369	skb_reset_mac_len(skb);
 370
 371	hdr = eth_hdr(skb);
 372	ether_addr_copy(hdr->h_source, ethh->addresses.eth_src);
 373	ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst);
 374	hdr->h_proto = skb->protocol;
 375
 376	skb_postpush_rcsum(skb, hdr, ETH_HLEN);
 377
 378	/* safe right before invalidate_flow_key */
 379	key->mac_proto = MAC_PROTO_ETHERNET;
 380	invalidate_flow_key(key);
 381	return 0;
 382}
 383
 384static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key,
 385		    const struct nshhdr *nh)
 386{
 387	int err;
 388
 389	err = nsh_push(skb, nh);
 390	if (err)
 391		return err;
 392
 393	/* safe right before invalidate_flow_key */
 394	key->mac_proto = MAC_PROTO_NONE;
 395	invalidate_flow_key(key);
 396	return 0;
 397}
 398
 399static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 400{
 401	int err;
 402
 403	err = nsh_pop(skb);
 404	if (err)
 405		return err;
 406
 407	/* safe right before invalidate_flow_key */
 408	if (skb->protocol == htons(ETH_P_TEB))
 409		key->mac_proto = MAC_PROTO_ETHERNET;
 410	else
 411		key->mac_proto = MAC_PROTO_NONE;
 412	invalidate_flow_key(key);
 413	return 0;
 414}
 415
 416static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
 417				  __be32 addr, __be32 new_addr)
 418{
 419	int transport_len = skb->len - skb_transport_offset(skb);
 420
 421	if (nh->frag_off & htons(IP_OFFSET))
 422		return;
 423
 424	if (nh->protocol == IPPROTO_TCP) {
 425		if (likely(transport_len >= sizeof(struct tcphdr)))
 426			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 427						 addr, new_addr, true);
 428	} else if (nh->protocol == IPPROTO_UDP) {
 429		if (likely(transport_len >= sizeof(struct udphdr))) {
 430			struct udphdr *uh = udp_hdr(skb);
 431
 432			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 433				inet_proto_csum_replace4(&uh->check, skb,
 434							 addr, new_addr, true);
 435				if (!uh->check)
 436					uh->check = CSUM_MANGLED_0;
 437			}
 438		}
 439	}
 440}
 441
 442static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 443			__be32 *addr, __be32 new_addr)
 444{
 445	update_ip_l4_checksum(skb, nh, *addr, new_addr);
 446	csum_replace4(&nh->check, *addr, new_addr);
 447	skb_clear_hash(skb);
 448	*addr = new_addr;
 449}
 450
 451static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 452				 __be32 addr[4], const __be32 new_addr[4])
 453{
 454	int transport_len = skb->len - skb_transport_offset(skb);
 455
 456	if (l4_proto == NEXTHDR_TCP) {
 457		if (likely(transport_len >= sizeof(struct tcphdr)))
 458			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 459						  addr, new_addr, true);
 460	} else if (l4_proto == NEXTHDR_UDP) {
 461		if (likely(transport_len >= sizeof(struct udphdr))) {
 462			struct udphdr *uh = udp_hdr(skb);
 463
 464			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 465				inet_proto_csum_replace16(&uh->check, skb,
 466							  addr, new_addr, true);
 467				if (!uh->check)
 468					uh->check = CSUM_MANGLED_0;
 469			}
 470		}
 471	} else if (l4_proto == NEXTHDR_ICMP) {
 472		if (likely(transport_len >= sizeof(struct icmp6hdr)))
 473			inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 474						  skb, addr, new_addr, true);
 475	}
 476}
 477
 478static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 479			   const __be32 mask[4], __be32 masked[4])
 480{
 481	masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
 482	masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
 483	masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
 484	masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
 485}
 486
 487static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 488			  __be32 addr[4], const __be32 new_addr[4],
 489			  bool recalculate_csum)
 490{
 491	if (recalculate_csum)
 492		update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 493
 494	skb_clear_hash(skb);
 495	memcpy(addr, new_addr, sizeof(__be32[4]));
 496}
 497
 498static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
 499{
 500	/* Bits 21-24 are always unmasked, so this retains their values. */
 501	OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
 502	OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
 503	OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
 504}
 505
 506static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 507		       u8 mask)
 508{
 509	new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
 510
 511	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 512	nh->ttl = new_ttl;
 513}
 514
 515static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 516		    const struct ovs_key_ipv4 *key,
 517		    const struct ovs_key_ipv4 *mask)
 518{
 519	struct iphdr *nh;
 520	__be32 new_addr;
 521	int err;
 522
 523	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 524				  sizeof(struct iphdr));
 525	if (unlikely(err))
 526		return err;
 527
 528	nh = ip_hdr(skb);
 529
 530	/* Setting an IP addresses is typically only a side effect of
 531	 * matching on them in the current userspace implementation, so it
 532	 * makes sense to check if the value actually changed.
 533	 */
 534	if (mask->ipv4_src) {
 535		new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 536
 537		if (unlikely(new_addr != nh->saddr)) {
 538			set_ip_addr(skb, nh, &nh->saddr, new_addr);
 539			flow_key->ipv4.addr.src = new_addr;
 540		}
 541	}
 542	if (mask->ipv4_dst) {
 543		new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 544
 545		if (unlikely(new_addr != nh->daddr)) {
 546			set_ip_addr(skb, nh, &nh->daddr, new_addr);
 547			flow_key->ipv4.addr.dst = new_addr;
 548		}
 549	}
 550	if (mask->ipv4_tos) {
 551		ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 552		flow_key->ip.tos = nh->tos;
 553	}
 554	if (mask->ipv4_ttl) {
 555		set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 556		flow_key->ip.ttl = nh->ttl;
 557	}
 558
 559	return 0;
 560}
 561
 562static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 563{
 564	return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 565}
 566
 567static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 568		    const struct ovs_key_ipv6 *key,
 569		    const struct ovs_key_ipv6 *mask)
 570{
 571	struct ipv6hdr *nh;
 572	int err;
 573
 574	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 575				  sizeof(struct ipv6hdr));
 576	if (unlikely(err))
 577		return err;
 578
 579	nh = ipv6_hdr(skb);
 580
 581	/* Setting an IP addresses is typically only a side effect of
 582	 * matching on them in the current userspace implementation, so it
 583	 * makes sense to check if the value actually changed.
 584	 */
 585	if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 586		__be32 *saddr = (__be32 *)&nh->saddr;
 587		__be32 masked[4];
 588
 589		mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 590
 591		if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 592			set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
 593				      true);
 594			memcpy(&flow_key->ipv6.addr.src, masked,
 595			       sizeof(flow_key->ipv6.addr.src));
 596		}
 597	}
 598	if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 599		unsigned int offset = 0;
 600		int flags = IP6_FH_F_SKIP_RH;
 601		bool recalc_csum = true;
 602		__be32 *daddr = (__be32 *)&nh->daddr;
 603		__be32 masked[4];
 604
 605		mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 606
 607		if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 608			if (ipv6_ext_hdr(nh->nexthdr))
 609				recalc_csum = (ipv6_find_hdr(skb, &offset,
 610							     NEXTHDR_ROUTING,
 611							     NULL, &flags)
 612					       != NEXTHDR_ROUTING);
 613
 614			set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
 615				      recalc_csum);
 616			memcpy(&flow_key->ipv6.addr.dst, masked,
 617			       sizeof(flow_key->ipv6.addr.dst));
 618		}
 619	}
 620	if (mask->ipv6_tclass) {
 621		ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
 622		flow_key->ip.tos = ipv6_get_dsfield(nh);
 623	}
 624	if (mask->ipv6_label) {
 625		set_ipv6_fl(nh, ntohl(key->ipv6_label),
 626			    ntohl(mask->ipv6_label));
 627		flow_key->ipv6.label =
 628		    *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 629	}
 630	if (mask->ipv6_hlimit) {
 631		OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
 632			       mask->ipv6_hlimit);
 633		flow_key->ip.ttl = nh->hop_limit;
 634	}
 635	return 0;
 636}
 637
 638static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
 639		   const struct nlattr *a)
 640{
 641	struct nshhdr *nh;
 642	size_t length;
 643	int err;
 644	u8 flags;
 645	u8 ttl;
 646	int i;
 647
 648	struct ovs_key_nsh key;
 649	struct ovs_key_nsh mask;
 650
 651	err = nsh_key_from_nlattr(a, &key, &mask);
 652	if (err)
 653		return err;
 654
 655	/* Make sure the NSH base header is there */
 656	if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
 657		return -ENOMEM;
 658
 659	nh = nsh_hdr(skb);
 660	length = nsh_hdr_len(nh);
 661
 662	/* Make sure the whole NSH header is there */
 663	err = skb_ensure_writable(skb, skb_network_offset(skb) +
 664				       length);
 665	if (unlikely(err))
 666		return err;
 667
 668	nh = nsh_hdr(skb);
 669	skb_postpull_rcsum(skb, nh, length);
 670	flags = nsh_get_flags(nh);
 671	flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
 672	flow_key->nsh.base.flags = flags;
 673	ttl = nsh_get_ttl(nh);
 674	ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
 675	flow_key->nsh.base.ttl = ttl;
 676	nsh_set_flags_and_ttl(nh, flags, ttl);
 677	nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
 678				  mask.base.path_hdr);
 679	flow_key->nsh.base.path_hdr = nh->path_hdr;
 680	switch (nh->mdtype) {
 681	case NSH_M_TYPE1:
 682		for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
 683			nh->md1.context[i] =
 684			    OVS_MASKED(nh->md1.context[i], key.context[i],
 685				       mask.context[i]);
 686		}
 687		memcpy(flow_key->nsh.context, nh->md1.context,
 688		       sizeof(nh->md1.context));
 689		break;
 690	case NSH_M_TYPE2:
 691		memset(flow_key->nsh.context, 0,
 692		       sizeof(flow_key->nsh.context));
 693		break;
 694	default:
 695		return -EINVAL;
 696	}
 697	skb_postpush_rcsum(skb, nh, length);
 698	return 0;
 699}
 700
 701/* Must follow skb_ensure_writable() since that can move the skb data. */
 702static void set_tp_port(struct sk_buff *skb, __be16 *port,
 703			__be16 new_port, __sum16 *check)
 704{
 705	inet_proto_csum_replace2(check, skb, *port, new_port, false);
 706	*port = new_port;
 707}
 708
 709static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 710		   const struct ovs_key_udp *key,
 711		   const struct ovs_key_udp *mask)
 712{
 713	struct udphdr *uh;
 714	__be16 src, dst;
 715	int err;
 716
 717	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 718				  sizeof(struct udphdr));
 719	if (unlikely(err))
 720		return err;
 721
 722	uh = udp_hdr(skb);
 723	/* Either of the masks is non-zero, so do not bother checking them. */
 724	src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
 725	dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 726
 727	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 728		if (likely(src != uh->source)) {
 729			set_tp_port(skb, &uh->source, src, &uh->check);
 730			flow_key->tp.src = src;
 731		}
 732		if (likely(dst != uh->dest)) {
 733			set_tp_port(skb, &uh->dest, dst, &uh->check);
 734			flow_key->tp.dst = dst;
 735		}
 736
 737		if (unlikely(!uh->check))
 738			uh->check = CSUM_MANGLED_0;
 739	} else {
 740		uh->source = src;
 741		uh->dest = dst;
 742		flow_key->tp.src = src;
 743		flow_key->tp.dst = dst;
 744	}
 745
 746	skb_clear_hash(skb);
 747
 748	return 0;
 749}
 750
 751static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 752		   const struct ovs_key_tcp *key,
 753		   const struct ovs_key_tcp *mask)
 754{
 755	struct tcphdr *th;
 756	__be16 src, dst;
 757	int err;
 758
 759	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 760				  sizeof(struct tcphdr));
 761	if (unlikely(err))
 762		return err;
 763
 764	th = tcp_hdr(skb);
 765	src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
 766	if (likely(src != th->source)) {
 767		set_tp_port(skb, &th->source, src, &th->check);
 768		flow_key->tp.src = src;
 769	}
 770	dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 771	if (likely(dst != th->dest)) {
 772		set_tp_port(skb, &th->dest, dst, &th->check);
 773		flow_key->tp.dst = dst;
 774	}
 775	skb_clear_hash(skb);
 776
 777	return 0;
 778}
 779
 780static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 781		    const struct ovs_key_sctp *key,
 782		    const struct ovs_key_sctp *mask)
 783{
 784	unsigned int sctphoff = skb_transport_offset(skb);
 785	struct sctphdr *sh;
 786	__le32 old_correct_csum, new_csum, old_csum;
 787	int err;
 788
 789	err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 790	if (unlikely(err))
 791		return err;
 792
 793	sh = sctp_hdr(skb);
 794	old_csum = sh->checksum;
 795	old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 796
 797	sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
 798	sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 799
 800	new_csum = sctp_compute_cksum(skb, sctphoff);
 801
 802	/* Carry any checksum errors through. */
 803	sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 804
 805	skb_clear_hash(skb);
 806	flow_key->tp.src = sh->source;
 807	flow_key->tp.dst = sh->dest;
 808
 809	return 0;
 810}
 811
 812static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 813{
 814	struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
 815	struct vport *vport = data->vport;
 816
 817	if (skb_cow_head(skb, data->l2_len) < 0) {
 818		kfree_skb(skb);
 819		return -ENOMEM;
 820	}
 821
 822	__skb_dst_copy(skb, data->dst);
 823	*OVS_CB(skb) = data->cb;
 824	skb->inner_protocol = data->inner_protocol;
 825	skb->vlan_tci = data->vlan_tci;
 826	skb->vlan_proto = data->vlan_proto;
 827
 828	/* Reconstruct the MAC header.  */
 829	skb_push(skb, data->l2_len);
 830	memcpy(skb->data, &data->l2_data, data->l2_len);
 831	skb_postpush_rcsum(skb, skb->data, data->l2_len);
 832	skb_reset_mac_header(skb);
 833
 834	if (eth_p_mpls(skb->protocol)) {
 835		skb->inner_network_header = skb->network_header;
 836		skb_set_network_header(skb, data->network_offset);
 837		skb_reset_mac_len(skb);
 838	}
 839
 840	ovs_vport_send(vport, skb, data->mac_proto);
 841	return 0;
 842}
 843
 844static unsigned int
 845ovs_dst_get_mtu(const struct dst_entry *dst)
 846{
 847	return dst->dev->mtu;
 848}
 849
 850static struct dst_ops ovs_dst_ops = {
 851	.family = AF_UNSPEC,
 852	.mtu = ovs_dst_get_mtu,
 853};
 854
 855/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 856 * ovs_vport_output(), which is called once per fragmented packet.
 857 */
 858static void prepare_frag(struct vport *vport, struct sk_buff *skb,
 859			 u16 orig_network_offset, u8 mac_proto)
 860{
 861	unsigned int hlen = skb_network_offset(skb);
 862	struct ovs_frag_data *data;
 863
 864	data = this_cpu_ptr(&ovs_frag_data_storage);
 865	data->dst = skb->_skb_refdst;
 866	data->vport = vport;
 867	data->cb = *OVS_CB(skb);
 868	data->inner_protocol = skb->inner_protocol;
 869	data->network_offset = orig_network_offset;
 870	data->vlan_tci = skb->vlan_tci;
 871	data->vlan_proto = skb->vlan_proto;
 872	data->mac_proto = mac_proto;
 873	data->l2_len = hlen;
 874	memcpy(&data->l2_data, skb->data, hlen);
 875
 876	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 877	skb_pull(skb, hlen);
 878}
 879
 880static void ovs_fragment(struct net *net, struct vport *vport,
 881			 struct sk_buff *skb, u16 mru,
 882			 struct sw_flow_key *key)
 883{
 884	u16 orig_network_offset = 0;
 885
 886	if (eth_p_mpls(skb->protocol)) {
 887		orig_network_offset = skb_network_offset(skb);
 888		skb->network_header = skb->inner_network_header;
 889	}
 890
 891	if (skb_network_offset(skb) > MAX_L2_LEN) {
 892		OVS_NLERR(1, "L2 header too long to fragment");
 893		goto err;
 894	}
 895
 896	if (key->eth.type == htons(ETH_P_IP)) {
 897		struct dst_entry ovs_dst;
 898		unsigned long orig_dst;
 899
 900		prepare_frag(vport, skb, orig_network_offset,
 901			     ovs_key_mac_proto(key));
 902		dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1,
 903			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 904		ovs_dst.dev = vport->dev;
 905
 906		orig_dst = skb->_skb_refdst;
 907		skb_dst_set_noref(skb, &ovs_dst);
 908		IPCB(skb)->frag_max_size = mru;
 909
 910		ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
 911		refdst_drop(orig_dst);
 912	} else if (key->eth.type == htons(ETH_P_IPV6)) {
 913		const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
 914		unsigned long orig_dst;
 915		struct rt6_info ovs_rt;
 916
 917		if (!v6ops)
 918			goto err;
 
 919
 920		prepare_frag(vport, skb, orig_network_offset,
 921			     ovs_key_mac_proto(key));
 922		memset(&ovs_rt, 0, sizeof(ovs_rt));
 923		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 924			 DST_OBSOLETE_NONE, DST_NOCOUNT);
 925		ovs_rt.dst.dev = vport->dev;
 926
 927		orig_dst = skb->_skb_refdst;
 928		skb_dst_set_noref(skb, &ovs_rt.dst);
 929		IP6CB(skb)->frag_max_size = mru;
 930
 931		v6ops->fragment(net, skb->sk, skb, ovs_vport_output);
 932		refdst_drop(orig_dst);
 933	} else {
 934		WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
 935			  ovs_vport_name(vport), ntohs(key->eth.type), mru,
 936			  vport->dev->mtu);
 937		goto err;
 938	}
 939
 940	return;
 941err:
 942	kfree_skb(skb);
 943}
 944
 945static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
 946		      struct sw_flow_key *key)
 947{
 948	struct vport *vport = ovs_vport_rcu(dp, out_port);
 949
 950	if (likely(vport)) {
 951		u16 mru = OVS_CB(skb)->mru;
 952		u32 cutlen = OVS_CB(skb)->cutlen;
 953
 954		if (unlikely(cutlen > 0)) {
 955			if (skb->len - cutlen > ovs_mac_header_len(key))
 956				pskb_trim(skb, skb->len - cutlen);
 957			else
 958				pskb_trim(skb, ovs_mac_header_len(key));
 959		}
 960
 961		if (likely(!mru ||
 962		           (skb->len <= mru + vport->dev->hard_header_len))) {
 963			ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
 964		} else if (mru <= vport->dev->mtu) {
 965			struct net *net = read_pnet(&dp->net);
 966
 967			ovs_fragment(net, vport, skb, mru, key);
 968		} else {
 969			kfree_skb(skb);
 970		}
 971	} else {
 972		kfree_skb(skb);
 973	}
 974}
 975
 976static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 977			    struct sw_flow_key *key, const struct nlattr *attr,
 978			    const struct nlattr *actions, int actions_len,
 979			    uint32_t cutlen)
 980{
 981	struct dp_upcall_info upcall;
 982	const struct nlattr *a;
 983	int rem;
 984
 985	memset(&upcall, 0, sizeof(upcall));
 986	upcall.cmd = OVS_PACKET_CMD_ACTION;
 987	upcall.mru = OVS_CB(skb)->mru;
 988
 989	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 990		 a = nla_next(a, &rem)) {
 991		switch (nla_type(a)) {
 992		case OVS_USERSPACE_ATTR_USERDATA:
 993			upcall.userdata = a;
 994			break;
 995
 996		case OVS_USERSPACE_ATTR_PID:
 997			upcall.portid = nla_get_u32(a);
 998			break;
 999
1000		case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
1001			/* Get out tunnel info. */
1002			struct vport *vport;
1003
1004			vport = ovs_vport_rcu(dp, nla_get_u32(a));
1005			if (vport) {
1006				int err;
1007
1008				err = dev_fill_metadata_dst(vport->dev, skb);
1009				if (!err)
1010					upcall.egress_tun_info = skb_tunnel_info(skb);
1011			}
1012
1013			break;
1014		}
1015
1016		case OVS_USERSPACE_ATTR_ACTIONS: {
1017			/* Include actions. */
1018			upcall.actions = actions;
1019			upcall.actions_len = actions_len;
1020			break;
1021		}
1022
1023		} /* End of switch. */
1024	}
1025
1026	return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
1027}
1028
1029/* When 'last' is true, sample() should always consume the 'skb'.
1030 * Otherwise, sample() should keep 'skb' intact regardless what
1031 * actions are executed within sample().
1032 */
1033static int sample(struct datapath *dp, struct sk_buff *skb,
1034		  struct sw_flow_key *key, const struct nlattr *attr,
1035		  bool last)
1036{
1037	struct nlattr *actions;
1038	struct nlattr *sample_arg;
1039	int rem = nla_len(attr);
1040	const struct sample_arg *arg;
1041	bool clone_flow_key;
1042
1043	/* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
1044	sample_arg = nla_data(attr);
1045	arg = nla_data(sample_arg);
1046	actions = nla_next(sample_arg, &rem);
1047
1048	if ((arg->probability != U32_MAX) &&
1049	    (!arg->probability || prandom_u32() > arg->probability)) {
1050		if (last)
1051			consume_skb(skb);
 
 
 
 
 
 
 
 
 
 
 
 
1052		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1053	}
1054
1055	clone_flow_key = !arg->exec;
1056	return clone_execute(dp, skb, key, 0, actions, rem, last,
1057			     clone_flow_key);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1058}
1059
1060static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
1061			 const struct nlattr *attr)
1062{
1063	struct ovs_action_hash *hash_act = nla_data(attr);
1064	u32 hash = 0;
1065
1066	/* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
1067	hash = skb_get_hash(skb);
1068	hash = jhash_1word(hash, hash_act->hash_basis);
1069	if (!hash)
1070		hash = 0x1;
1071
1072	key->ovs_flow_hash = hash;
1073}
1074
1075static int execute_set_action(struct sk_buff *skb,
1076			      struct sw_flow_key *flow_key,
1077			      const struct nlattr *a)
1078{
1079	/* Only tunnel set execution is supported without a mask. */
1080	if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1081		struct ovs_tunnel_info *tun = nla_data(a);
1082
1083		skb_dst_drop(skb);
1084		dst_hold((struct dst_entry *)tun->tun_dst);
1085		skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
1086		return 0;
1087	}
1088
1089	return -EINVAL;
1090}
1091
1092/* Mask is at the midpoint of the data. */
1093#define get_mask(a, type) ((const type)nla_data(a) + 1)
1094
1095static int execute_masked_set_action(struct sk_buff *skb,
1096				     struct sw_flow_key *flow_key,
1097				     const struct nlattr *a)
1098{
1099	int err = 0;
1100
1101	switch (nla_type(a)) {
1102	case OVS_KEY_ATTR_PRIORITY:
1103		OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1104			       *get_mask(a, u32 *));
1105		flow_key->phy.priority = skb->priority;
1106		break;
1107
1108	case OVS_KEY_ATTR_SKB_MARK:
1109		OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1110		flow_key->phy.skb_mark = skb->mark;
1111		break;
1112
1113	case OVS_KEY_ATTR_TUNNEL_INFO:
1114		/* Masked data not supported for tunnel. */
1115		err = -EINVAL;
1116		break;
1117
1118	case OVS_KEY_ATTR_ETHERNET:
1119		err = set_eth_addr(skb, flow_key, nla_data(a),
1120				   get_mask(a, struct ovs_key_ethernet *));
1121		break;
1122
1123	case OVS_KEY_ATTR_NSH:
1124		err = set_nsh(skb, flow_key, a);
1125		break;
1126
1127	case OVS_KEY_ATTR_IPV4:
1128		err = set_ipv4(skb, flow_key, nla_data(a),
1129			       get_mask(a, struct ovs_key_ipv4 *));
1130		break;
1131
1132	case OVS_KEY_ATTR_IPV6:
1133		err = set_ipv6(skb, flow_key, nla_data(a),
1134			       get_mask(a, struct ovs_key_ipv6 *));
1135		break;
1136
1137	case OVS_KEY_ATTR_TCP:
1138		err = set_tcp(skb, flow_key, nla_data(a),
1139			      get_mask(a, struct ovs_key_tcp *));
1140		break;
1141
1142	case OVS_KEY_ATTR_UDP:
1143		err = set_udp(skb, flow_key, nla_data(a),
1144			      get_mask(a, struct ovs_key_udp *));
1145		break;
1146
1147	case OVS_KEY_ATTR_SCTP:
1148		err = set_sctp(skb, flow_key, nla_data(a),
1149			       get_mask(a, struct ovs_key_sctp *));
1150		break;
1151
1152	case OVS_KEY_ATTR_MPLS:
1153		err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1154								    __be32 *));
1155		break;
1156
1157	case OVS_KEY_ATTR_CT_STATE:
1158	case OVS_KEY_ATTR_CT_ZONE:
1159	case OVS_KEY_ATTR_CT_MARK:
1160	case OVS_KEY_ATTR_CT_LABELS:
1161	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1162	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1163		err = -EINVAL;
1164		break;
1165	}
1166
1167	return err;
1168}
1169
1170static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1171			  struct sw_flow_key *key,
1172			  const struct nlattr *a, bool last)
1173{
1174	u32 recirc_id;
 
1175
1176	if (!is_flow_key_valid(key)) {
1177		int err;
1178
1179		err = ovs_flow_key_update(skb, key);
1180		if (err)
1181			return err;
1182	}
1183	BUG_ON(!is_flow_key_valid(key));
1184
1185	recirc_id = nla_get_u32(a);
1186	return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1187}
1188
1189/* Execute a list of actions against 'skb'. */
1190static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1191			      struct sw_flow_key *key,
1192			      const struct nlattr *attr, int len)
1193{
 
 
 
 
 
 
1194	const struct nlattr *a;
1195	int rem;
1196
1197	for (a = attr, rem = len; rem > 0;
1198	     a = nla_next(a, &rem)) {
1199		int err = 0;
1200
1201		switch (nla_type(a)) {
1202		case OVS_ACTION_ATTR_OUTPUT: {
1203			int port = nla_get_u32(a);
1204			struct sk_buff *clone;
1205
1206			/* Every output action needs a separate clone
1207			 * of 'skb', In case the output action is the
1208			 * last action, cloning can be avoided.
1209			 */
1210			if (nla_is_last(a, rem)) {
1211				do_output(dp, skb, port, key);
1212				/* 'skb' has been used for output.
1213				 */
1214				return 0;
1215			}
1216
1217			clone = skb_clone(skb, GFP_ATOMIC);
1218			if (clone)
1219				do_output(dp, clone, port, key);
1220			OVS_CB(skb)->cutlen = 0;
 
 
 
 
 
 
1221			break;
1222		}
1223
1224		case OVS_ACTION_ATTR_TRUNC: {
1225			struct ovs_action_trunc *trunc = nla_data(a);
1226
1227			if (skb->len > trunc->max_len)
1228				OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1229			break;
1230		}
1231
1232		case OVS_ACTION_ATTR_USERSPACE:
1233			output_userspace(dp, skb, key, a, attr,
1234						     len, OVS_CB(skb)->cutlen);
1235			OVS_CB(skb)->cutlen = 0;
1236			break;
1237
1238		case OVS_ACTION_ATTR_HASH:
1239			execute_hash(skb, key, a);
1240			break;
1241
1242		case OVS_ACTION_ATTR_PUSH_MPLS:
1243			err = push_mpls(skb, key, nla_data(a));
1244			break;
1245
1246		case OVS_ACTION_ATTR_POP_MPLS:
1247			err = pop_mpls(skb, key, nla_get_be16(a));
1248			break;
1249
1250		case OVS_ACTION_ATTR_PUSH_VLAN:
1251			err = push_vlan(skb, key, nla_data(a));
1252			break;
1253
1254		case OVS_ACTION_ATTR_POP_VLAN:
1255			err = pop_vlan(skb, key);
1256			break;
1257
1258		case OVS_ACTION_ATTR_RECIRC: {
1259			bool last = nla_is_last(a, rem);
1260
1261			err = execute_recirc(dp, skb, key, a, last);
1262			if (last) {
1263				/* If this is the last action, the skb has
1264				 * been consumed or freed.
1265				 * Return immediately.
1266				 */
1267				return err;
1268			}
1269			break;
1270		}
1271
1272		case OVS_ACTION_ATTR_SET:
1273			err = execute_set_action(skb, key, nla_data(a));
1274			break;
1275
1276		case OVS_ACTION_ATTR_SET_MASKED:
1277		case OVS_ACTION_ATTR_SET_TO_MASKED:
1278			err = execute_masked_set_action(skb, key, nla_data(a));
1279			break;
1280
1281		case OVS_ACTION_ATTR_SAMPLE: {
1282			bool last = nla_is_last(a, rem);
1283
1284			err = sample(dp, skb, key, a, last);
1285			if (last)
1286				return err;
1287
1288			break;
1289		}
1290
1291		case OVS_ACTION_ATTR_CT:
1292			if (!is_flow_key_valid(key)) {
1293				err = ovs_flow_key_update(skb, key);
1294				if (err)
1295					return err;
1296			}
1297
1298			err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1299					     nla_data(a));
1300
1301			/* Hide stolen IP fragments from user space. */
1302			if (err)
1303				return err == -EINPROGRESS ? 0 : err;
1304			break;
1305
1306		case OVS_ACTION_ATTR_CT_CLEAR:
1307			err = ovs_ct_clear(skb, key);
1308			break;
1309
1310		case OVS_ACTION_ATTR_PUSH_ETH:
1311			err = push_eth(skb, key, nla_data(a));
1312			break;
1313
1314		case OVS_ACTION_ATTR_POP_ETH:
1315			err = pop_eth(skb, key);
1316			break;
1317
1318		case OVS_ACTION_ATTR_PUSH_NSH: {
1319			u8 buffer[NSH_HDR_MAX_LEN];
1320			struct nshhdr *nh = (struct nshhdr *)buffer;
1321
1322			err = nsh_hdr_from_nlattr(nla_data(a), nh,
1323						  NSH_HDR_MAX_LEN);
1324			if (unlikely(err))
1325				break;
1326			err = push_nsh(skb, key, nh);
1327			break;
1328		}
1329
1330		case OVS_ACTION_ATTR_POP_NSH:
1331			err = pop_nsh(skb, key);
1332			break;
1333
1334		case OVS_ACTION_ATTR_METER:
1335			if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
1336				consume_skb(skb);
1337				return 0;
1338			}
1339		}
1340
1341		if (unlikely(err)) {
1342			kfree_skb(skb);
1343			return err;
1344		}
1345	}
1346
1347	consume_skb(skb);
1348	return 0;
1349}
1350
1351/* Execute the actions on the clone of the packet. The effect of the
1352 * execution does not affect the original 'skb' nor the original 'key'.
1353 *
1354 * The execution may be deferred in case the actions can not be executed
1355 * immediately.
1356 */
1357static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1358			 struct sw_flow_key *key, u32 recirc_id,
1359			 const struct nlattr *actions, int len,
1360			 bool last, bool clone_flow_key)
1361{
1362	struct deferred_action *da;
1363	struct sw_flow_key *clone;
1364
1365	skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1366	if (!skb) {
1367		/* Out of memory, skip this action.
1368		 */
1369		return 0;
1370	}
1371
1372	/* When clone_flow_key is false, the 'key' will not be change
1373	 * by the actions, then the 'key' can be used directly.
1374	 * Otherwise, try to clone key from the next recursion level of
1375	 * 'flow_keys'. If clone is successful, execute the actions
1376	 * without deferring.
1377	 */
1378	clone = clone_flow_key ? clone_key(key) : key;
1379	if (clone) {
1380		int err = 0;
1381
1382		if (actions) { /* Sample action */
1383			if (clone_flow_key)
1384				__this_cpu_inc(exec_actions_level);
1385
1386			err = do_execute_actions(dp, skb, clone,
1387						 actions, len);
1388
1389			if (clone_flow_key)
1390				__this_cpu_dec(exec_actions_level);
1391		} else { /* Recirc action */
1392			clone->recirc_id = recirc_id;
1393			ovs_dp_process_packet(skb, clone);
1394		}
1395		return err;
1396	}
1397
1398	/* Out of 'flow_keys' space. Defer actions */
1399	da = add_deferred_actions(skb, key, actions, len);
1400	if (da) {
1401		if (!actions) { /* Recirc action */
1402			key = &da->pkt_key;
1403			key->recirc_id = recirc_id;
1404		}
1405	} else {
1406		/* Out of per CPU action FIFO space. Drop the 'skb' and
1407		 * log an error.
1408		 */
1409		kfree_skb(skb);
1410
1411		if (net_ratelimit()) {
1412			if (actions) { /* Sample action */
1413				pr_warn("%s: deferred action limit reached, drop sample action\n",
1414					ovs_dp_name(dp));
1415			} else {  /* Recirc action */
1416				pr_warn("%s: deferred action limit reached, drop recirc action\n",
1417					ovs_dp_name(dp));
1418			}
1419		}
1420	}
1421	return 0;
1422}
1423
1424static void process_deferred_actions(struct datapath *dp)
1425{
1426	struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1427
1428	/* Do not touch the FIFO in case there is no deferred actions. */
1429	if (action_fifo_is_empty(fifo))
1430		return;
1431
1432	/* Finishing executing all deferred actions. */
1433	do {
1434		struct deferred_action *da = action_fifo_get(fifo);
1435		struct sk_buff *skb = da->skb;
1436		struct sw_flow_key *key = &da->pkt_key;
1437		const struct nlattr *actions = da->actions;
1438		int actions_len = da->actions_len;
1439
1440		if (actions)
1441			do_execute_actions(dp, skb, key, actions, actions_len);
 
1442		else
1443			ovs_dp_process_packet(skb, key);
1444	} while (!action_fifo_is_empty(fifo));
1445
1446	/* Reset FIFO for the next packet.  */
1447	action_fifo_init(fifo);
1448}
1449
1450/* Execute a list of actions against 'skb'. */
1451int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1452			const struct sw_flow_actions *acts,
1453			struct sw_flow_key *key)
1454{
1455	int err, level;
1456
1457	level = __this_cpu_inc_return(exec_actions_level);
1458	if (unlikely(level > OVS_RECURSION_LIMIT)) {
1459		net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1460				     ovs_dp_name(dp));
1461		kfree_skb(skb);
1462		err = -ENETDOWN;
1463		goto out;
1464	}
1465
1466	OVS_CB(skb)->acts_origlen = acts->orig_len;
1467	err = do_execute_actions(dp, skb, key,
1468				 acts->actions, acts->actions_len);
1469
1470	if (level == 1)
1471		process_deferred_actions(dp);
1472
1473out:
1474	__this_cpu_dec(exec_actions_level);
1475	return err;
1476}
1477
1478int action_fifos_init(void)
1479{
1480	action_fifos = alloc_percpu(struct action_fifo);
1481	if (!action_fifos)
1482		return -ENOMEM;
1483
1484	flow_keys = alloc_percpu(struct action_flow_keys);
1485	if (!flow_keys) {
1486		free_percpu(action_fifos);
1487		return -ENOMEM;
1488	}
1489
1490	return 0;
1491}
1492
1493void action_fifos_exit(void)
1494{
1495	free_percpu(action_fifos);
1496	free_percpu(flow_keys);
1497}