net/openvswitch/actions.c

   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/netfilter_ipv6.h>
  13 #include <linux/sctp.h>
  14 #include <linux/tcp.h>
  15 #include <linux/udp.h>
  16 #include <linux/in6.h>
  17 #include <linux/if_arp.h>
  18 #include <linux/if_vlan.h>
  19
  20 #include <net/dst.h>
  21 #include <net/ip.h>
  22 #include <net/ipv6.h>
  23 #include <net/ip6_fib.h>
  24 #include <net/checksum.h>
  25 #include <net/dsfield.h>
  26 #include <net/mpls.h>
  27 #include <net/sctp/checksum.h>
  28
  29 #include "datapath.h"
  30 #include "flow.h"
  31 #include "conntrack.h"
  32 #include "vport.h"
  33 #include "flow_netlink.h"
  34
  35 struct 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)
  45 struct 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
  58 static 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)
  63 struct 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
  70 struct action_flow_keys {
  71         struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
  72 };
  73
  74 static struct action_fifo __percpu *action_fifos;
  75 static struct action_flow_keys __percpu *flow_keys;
  76 static 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  */
  81 static 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
  95 static void action_fifo_init(struct action_fifo *fifo)
  96 {
  97         fifo->head = 0;
  98         fifo->tail = 0;
  99 }
 100
 101 static bool action_fifo_is_empty(const struct action_fifo *fifo)
 102 {
 103         return (fifo->head == fifo->tail);
 104 }
 105
 106 static 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
 114 static 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 */
 123 static 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
 143 static void invalidate_flow_key(struct sw_flow_key *key)
 144 {
 145         key->mac_proto |= SW_FLOW_KEY_INVALID;
 146 }
 147
 148 static bool is_flow_key_valid(const struct sw_flow_key *key)
 149 {
 150         return !(key->mac_proto & SW_FLOW_KEY_INVALID);
 151 }
 152
 153 static 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
 159 static 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
 163 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 164                      const struct ovs_action_push_mpls *mpls)
 165 {
 166         int err;
 167
 168         err = skb_mpls_push(skb, mpls->mpls_lse, mpls->mpls_ethertype,
 169                             skb->mac_len);
 170         if (err)
 171                 return err;
 172
 173         invalidate_flow_key(key);
 174         return 0;
 175 }
 176
 177 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 178                     const __be16 ethertype)
 179 {
 180         int err;
 181
 182         err = skb_mpls_pop(skb, ethertype, skb->mac_len);
 183         if (err)
 184                 return err;
 185
 186         invalidate_flow_key(key);
 187         return 0;
 188 }
 189
 190 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 191                     const __be32 *mpls_lse, const __be32 *mask)
 192 {
 193         struct mpls_shim_hdr *stack;
 194         __be32 lse;
 195         int err;
 196
 197         stack = mpls_hdr(skb);
 198         lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
 199         err = skb_mpls_update_lse(skb, lse);
 200         if (err)
 201                 return err;
 202
 203         flow_key->mpls.top_lse = lse;
 204         return 0;
 205 }
 206
 207 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 208 {
 209         int err;
 210
 211         err = skb_vlan_pop(skb);
 212         if (skb_vlan_tag_present(skb)) {
 213                 invalidate_flow_key(key);
 214         } else {
 215                 key->eth.vlan.tci = 0;
 216                 key->eth.vlan.tpid = 0;
 217         }
 218         return err;
 219 }
 220
 221 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 222                      const struct ovs_action_push_vlan *vlan)
 223 {
 224         if (skb_vlan_tag_present(skb)) {
 225                 invalidate_flow_key(key);
 226         } else {
 227                 key->eth.vlan.tci = vlan->vlan_tci;
 228                 key->eth.vlan.tpid = vlan->vlan_tpid;
 229         }
 230         return skb_vlan_push(skb, vlan->vlan_tpid,
 231                              ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
 232 }
 233
 234 /* 'src' is already properly masked. */
 235 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 236 {
 237         u16 *dst = (u16 *)dst_;
 238         const u16 *src = (const u16 *)src_;
 239         const u16 *mask = (const u16 *)mask_;
 240
 241         OVS_SET_MASKED(dst[0], src[0], mask[0]);
 242         OVS_SET_MASKED(dst[1], src[1], mask[1]);
 243         OVS_SET_MASKED(dst[2], src[2], mask[2]);
 244 }
 245
 246 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 247                         const struct ovs_key_ethernet *key,
 248                         const struct ovs_key_ethernet *mask)
 249 {
 250         int err;
 251
 252         err = skb_ensure_writable(skb, ETH_HLEN);
 253         if (unlikely(err))
 254                 return err;
 255
 256         skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 257
 258         ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 259                                mask->eth_src);
 260         ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 261                                mask->eth_dst);
 262
 263         skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 264
 265         ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 266         ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 267         return 0;
 268 }
 269
 270 /* pop_eth does not support VLAN packets as this action is never called
 271  * for them.
 272  */
 273 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
 274 {
 275         skb_pull_rcsum(skb, ETH_HLEN);
 276         skb_reset_mac_header(skb);
 277         skb_reset_mac_len(skb);
 278
 279         /* safe right before invalidate_flow_key */
 280         key->mac_proto = MAC_PROTO_NONE;
 281         invalidate_flow_key(key);
 282         return 0;
 283 }
 284
 285 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
 286                     const struct ovs_action_push_eth *ethh)
 287 {
 288         struct ethhdr *hdr;
 289
 290         /* Add the new Ethernet header */
 291         if (skb_cow_head(skb, ETH_HLEN) < 0)
 292                 return -ENOMEM;
 293
 294         skb_push(skb, ETH_HLEN);
 295         skb_reset_mac_header(skb);
 296         skb_reset_mac_len(skb);
 297
 298         hdr = eth_hdr(skb);
 299         ether_addr_copy(hdr->h_source, ethh->addresses.eth_src);
 300         ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst);
 301         hdr->h_proto = skb->protocol;
 302
 303         skb_postpush_rcsum(skb, hdr, ETH_HLEN);
 304
 305         /* safe right before invalidate_flow_key */
 306         key->mac_proto = MAC_PROTO_ETHERNET;
 307         invalidate_flow_key(key);
 308         return 0;
 309 }
 310
 311 static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key,
 312                     const struct nshhdr *nh)
 313 {
 314         int err;
 315
 316         err = nsh_push(skb, nh);
 317         if (err)
 318                 return err;
 319
 320         /* safe right before invalidate_flow_key */
 321         key->mac_proto = MAC_PROTO_NONE;
 322         invalidate_flow_key(key);
 323         return 0;
 324 }
 325
 326 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 327 {
 328         int err;
 329
 330         err = nsh_pop(skb);
 331         if (err)
 332                 return err;
 333
 334         /* safe right before invalidate_flow_key */
 335         if (skb->protocol == htons(ETH_P_TEB))
 336                 key->mac_proto = MAC_PROTO_ETHERNET;
 337         else
 338                 key->mac_proto = MAC_PROTO_NONE;
 339         invalidate_flow_key(key);
 340         return 0;
 341 }
 342
 343 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
 344                                   __be32 addr, __be32 new_addr)
 345 {
 346         int transport_len = skb->len - skb_transport_offset(skb);
 347
 348         if (nh->frag_off & htons(IP_OFFSET))
 349                 return;
 350
 351         if (nh->protocol == IPPROTO_TCP) {
 352                 if (likely(transport_len >= sizeof(struct tcphdr)))
 353                         inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 354                                                  addr, new_addr, true);
 355         } else if (nh->protocol == IPPROTO_UDP) {
 356                 if (likely(transport_len >= sizeof(struct udphdr))) {
 357                         struct udphdr *uh = udp_hdr(skb);
 358
 359                         if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 360                                 inet_proto_csum_replace4(&uh->check, skb,
 361                                                          addr, new_addr, true);
 362                                 if (!uh->check)
 363                                         uh->check = CSUM_MANGLED_0;
 364                         }
 365                 }
 366         }
 367 }
 368
 369 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 370                         __be32 *addr, __be32 new_addr)
 371 {
 372         update_ip_l4_checksum(skb, nh, *addr, new_addr);
 373         csum_replace4(&nh->check, *addr, new_addr);
 374         skb_clear_hash(skb);
 375         *addr = new_addr;
 376 }
 377
 378 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 379                                  __be32 addr[4], const __be32 new_addr[4])
 380 {
 381         int transport_len = skb->len - skb_transport_offset(skb);
 382
 383         if (l4_proto == NEXTHDR_TCP) {
 384                 if (likely(transport_len >= sizeof(struct tcphdr)))
 385                         inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 386                                                   addr, new_addr, true);
 387         } else if (l4_proto == NEXTHDR_UDP) {
 388                 if (likely(transport_len >= sizeof(struct udphdr))) {
 389                         struct udphdr *uh = udp_hdr(skb);
 390
 391                         if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 392                                 inet_proto_csum_replace16(&uh->check, skb,
 393                                                           addr, new_addr, true);
 394                                 if (!uh->check)
 395                                         uh->check = CSUM_MANGLED_0;
 396                         }
 397                 }
 398         } else if (l4_proto == NEXTHDR_ICMP) {
 399                 if (likely(transport_len >= sizeof(struct icmp6hdr)))
 400                         inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 401                                                   skb, addr, new_addr, true);
 402         }
 403 }
 404
 405 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 406                            const __be32 mask[4], __be32 masked[4])
 407 {
 408         masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
 409         masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
 410         masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
 411         masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
 412 }
 413
 414 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 415                           __be32 addr[4], const __be32 new_addr[4],
 416                           bool recalculate_csum)
 417 {
 418         if (recalculate_csum)
 419                 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 420
 421         skb_clear_hash(skb);
 422         memcpy(addr, new_addr, sizeof(__be32[4]));
 423 }
 424
 425 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
 426 {
 427         /* Bits 21-24 are always unmasked, so this retains their values. */
 428         OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
 429         OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
 430         OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
 431 }
 432
 433 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 434                        u8 mask)
 435 {
 436         new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
 437
 438         csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 439         nh->ttl = new_ttl;
 440 }
 441
 442 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 443                     const struct ovs_key_ipv4 *key,
 444                     const struct ovs_key_ipv4 *mask)
 445 {
 446         struct iphdr *nh;
 447         __be32 new_addr;
 448         int err;
 449
 450         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 451                                   sizeof(struct iphdr));
 452         if (unlikely(err))
 453                 return err;
 454
 455         nh = ip_hdr(skb);
 456
 457         /* Setting an IP addresses is typically only a side effect of
 458          * matching on them in the current userspace implementation, so it
 459          * makes sense to check if the value actually changed.
 460          */
 461         if (mask->ipv4_src) {
 462                 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 463
 464                 if (unlikely(new_addr != nh->saddr)) {
 465                         set_ip_addr(skb, nh, &nh->saddr, new_addr);
 466                         flow_key->ipv4.addr.src = new_addr;
 467                 }
 468         }
 469         if (mask->ipv4_dst) {
 470                 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 471
 472                 if (unlikely(new_addr != nh->daddr)) {
 473                         set_ip_addr(skb, nh, &nh->daddr, new_addr);
 474                         flow_key->ipv4.addr.dst = new_addr;
 475                 }
 476         }
 477         if (mask->ipv4_tos) {
 478                 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 479                 flow_key->ip.tos = nh->tos;
 480         }
 481         if (mask->ipv4_ttl) {
 482                 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 483                 flow_key->ip.ttl = nh->ttl;
 484         }
 485
 486         return 0;
 487 }
 488
 489 static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 490 {
 491         return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 492 }
 493
 494 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 495                     const struct ovs_key_ipv6 *key,
 496                     const struct ovs_key_ipv6 *mask)
 497 {
 498         struct ipv6hdr *nh;
 499         int err;
 500
 501         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 502                                   sizeof(struct ipv6hdr));
 503         if (unlikely(err))
 504                 return err;
 505
 506         nh = ipv6_hdr(skb);
 507
 508         /* Setting an IP addresses is typically only a side effect of
 509          * matching on them in the current userspace implementation, so it
 510          * makes sense to check if the value actually changed.
 511          */
 512         if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 513                 __be32 *saddr = (__be32 *)&nh->saddr;
 514                 __be32 masked[4];
 515
 516                 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 517
 518                 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 519                         set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
 520                                       true);
 521                         memcpy(&flow_key->ipv6.addr.src, masked,
 522                                sizeof(flow_key->ipv6.addr.src));
 523                 }
 524         }
 525         if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 526                 unsigned int offset = 0;
 527                 int flags = IP6_FH_F_SKIP_RH;
 528                 bool recalc_csum = true;
 529                 __be32 *daddr = (__be32 *)&nh->daddr;
 530                 __be32 masked[4];
 531
 532                 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 533
 534                 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 535                         if (ipv6_ext_hdr(nh->nexthdr))
 536                                 recalc_csum = (ipv6_find_hdr(skb, &offset,
 537                                                              NEXTHDR_ROUTING,
 538                                                              NULL, &flags)
 539                                                != NEXTHDR_ROUTING);
 540
 541                         set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
 542                                       recalc_csum);
 543                         memcpy(&flow_key->ipv6.addr.dst, masked,
 544                                sizeof(flow_key->ipv6.addr.dst));
 545                 }
 546         }
 547         if (mask->ipv6_tclass) {
 548                 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
 549                 flow_key->ip.tos = ipv6_get_dsfield(nh);
 550         }
 551         if (mask->ipv6_label) {
 552                 set_ipv6_fl(nh, ntohl(key->ipv6_label),
 553                             ntohl(mask->ipv6_label));
 554                 flow_key->ipv6.label =
 555                     *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 556         }
 557         if (mask->ipv6_hlimit) {
 558                 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
 559                                mask->ipv6_hlimit);
 560                 flow_key->ip.ttl = nh->hop_limit;
 561         }
 562         return 0;
 563 }
 564
 565 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
 566                    const struct nlattr *a)
 567 {
 568         struct nshhdr *nh;
 569         size_t length;
 570         int err;
 571         u8 flags;
 572         u8 ttl;
 573         int i;
 574
 575         struct ovs_key_nsh key;
 576         struct ovs_key_nsh mask;
 577
 578         err = nsh_key_from_nlattr(a, &key, &mask);
 579         if (err)
 580                 return err;
 581
 582         /* Make sure the NSH base header is there */
 583         if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
 584                 return -ENOMEM;
 585
 586         nh = nsh_hdr(skb);
 587         length = nsh_hdr_len(nh);
 588
 589         /* Make sure the whole NSH header is there */
 590         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 591                                        length);
 592         if (unlikely(err))
 593                 return err;
 594
 595         nh = nsh_hdr(skb);
 596         skb_postpull_rcsum(skb, nh, length);
 597         flags = nsh_get_flags(nh);
 598         flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
 599         flow_key->nsh.base.flags = flags;
 600         ttl = nsh_get_ttl(nh);
 601         ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
 602         flow_key->nsh.base.ttl = ttl;
 603         nsh_set_flags_and_ttl(nh, flags, ttl);
 604         nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
 605                                   mask.base.path_hdr);
 606         flow_key->nsh.base.path_hdr = nh->path_hdr;
 607         switch (nh->mdtype) {
 608         case NSH_M_TYPE1:
 609                 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
 610                         nh->md1.context[i] =
 611                             OVS_MASKED(nh->md1.context[i], key.context[i],
 612                                        mask.context[i]);
 613                 }
 614                 memcpy(flow_key->nsh.context, nh->md1.context,
 615                        sizeof(nh->md1.context));
 616                 break;
 617         case NSH_M_TYPE2:
 618                 memset(flow_key->nsh.context, 0,
 619                        sizeof(flow_key->nsh.context));
 620                 break;
 621         default:
 622                 return -EINVAL;
 623         }
 624         skb_postpush_rcsum(skb, nh, length);
 625         return 0;
 626 }
 627
 628 /* Must follow skb_ensure_writable() since that can move the skb data. */
 629 static void set_tp_port(struct sk_buff *skb, __be16 *port,
 630                         __be16 new_port, __sum16 *check)
 631 {
 632         inet_proto_csum_replace2(check, skb, *port, new_port, false);
 633         *port = new_port;
 634 }
 635
 636 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 637                    const struct ovs_key_udp *key,
 638                    const struct ovs_key_udp *mask)
 639 {
 640         struct udphdr *uh;
 641         __be16 src, dst;
 642         int err;
 643
 644         err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 645                                   sizeof(struct udphdr));
 646         if (unlikely(err))
 647                 return err;
 648
 649         uh = udp_hdr(skb);
 650         /* Either of the masks is non-zero, so do not bother checking them. */
 651         src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
 652         dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 653
 654         if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 655                 if (likely(src != uh->source)) {
 656                         set_tp_port(skb, &uh->source, src, &uh->check);
 657                         flow_key->tp.src = src;
 658                 }
 659                 if (likely(dst != uh->dest)) {
 660                         set_tp_port(skb, &uh->dest, dst, &uh->check);
 661                         flow_key->tp.dst = dst;
 662                 }
 663
 664                 if (unlikely(!uh->check))
 665                         uh->check = CSUM_MANGLED_0;
 666         } else {
 667                 uh->source = src;
 668                 uh->dest = dst;
 669                 flow_key->tp.src = src;
 670                 flow_key->tp.dst = dst;
 671         }
 672
 673         skb_clear_hash(skb);
 674
 675         return 0;
 676 }
 677
 678 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 679                    const struct ovs_key_tcp *key,
 680                    const struct ovs_key_tcp *mask)
 681 {
 682         struct tcphdr *th;
 683         __be16 src, dst;
 684         int err;
 685
 686         err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 687                                   sizeof(struct tcphdr));
 688         if (unlikely(err))
 689                 return err;
 690
 691         th = tcp_hdr(skb);
 692         src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
 693         if (likely(src != th->source)) {
 694                 set_tp_port(skb, &th->source, src, &th->check);
 695                 flow_key->tp.src = src;
 696         }
 697         dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 698         if (likely(dst != th->dest)) {
 699                 set_tp_port(skb, &th->dest, dst, &th->check);
 700                 flow_key->tp.dst = dst;
 701         }
 702         skb_clear_hash(skb);
 703
 704         return 0;
 705 }
 706
 707 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 708                     const struct ovs_key_sctp *key,
 709                     const struct ovs_key_sctp *mask)
 710 {
 711         unsigned int sctphoff = skb_transport_offset(skb);
 712         struct sctphdr *sh;
 713         __le32 old_correct_csum, new_csum, old_csum;
 714         int err;
 715
 716         err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 717         if (unlikely(err))
 718                 return err;
 719
 720         sh = sctp_hdr(skb);
 721         old_csum = sh->checksum;
 722         old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 723
 724         sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
 725         sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 726
 727         new_csum = sctp_compute_cksum(skb, sctphoff);
 728
 729         /* Carry any checksum errors through. */
 730         sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 731
 732         skb_clear_hash(skb);
 733         flow_key->tp.src = sh->source;
 734         flow_key->tp.dst = sh->dest;
 735
 736         return 0;
 737 }
 738
 739 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 740 {
 741         struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
 742         struct vport *vport = data->vport;
 743
 744         if (skb_cow_head(skb, data->l2_len) < 0) {
 745                 kfree_skb(skb);
 746                 return -ENOMEM;
 747         }
 748
 749         __skb_dst_copy(skb, data->dst);
 750         *OVS_CB(skb) = data->cb;
 751         skb->inner_protocol = data->inner_protocol;
 752         if (data->vlan_tci & VLAN_CFI_MASK)
 753                 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK);
 754         else
 755                 __vlan_hwaccel_clear_tag(skb);
 756
 757         /* Reconstruct the MAC header.  */
 758         skb_push(skb, data->l2_len);
 759         memcpy(skb->data, &data->l2_data, data->l2_len);
 760         skb_postpush_rcsum(skb, skb->data, data->l2_len);
 761         skb_reset_mac_header(skb);
 762
 763         if (eth_p_mpls(skb->protocol)) {
 764                 skb->inner_network_header = skb->network_header;
 765                 skb_set_network_header(skb, data->network_offset);
 766                 skb_reset_mac_len(skb);
 767         }
 768
 769         ovs_vport_send(vport, skb, data->mac_proto);
 770         return 0;
 771 }
 772
 773 static unsigned int
 774 ovs_dst_get_mtu(const struct dst_entry *dst)
 775 {
 776         return dst->dev->mtu;
 777 }
 778
 779 static struct dst_ops ovs_dst_ops = {
 780         .family = AF_UNSPEC,
 781         .mtu = ovs_dst_get_mtu,
 782 };
 783
 784 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 785  * ovs_vport_output(), which is called once per fragmented packet.
 786  */
 787 static void prepare_frag(struct vport *vport, struct sk_buff *skb,
 788                          u16 orig_network_offset, u8 mac_proto)
 789 {
 790         unsigned int hlen = skb_network_offset(skb);
 791         struct ovs_frag_data *data;
 792
 793         data = this_cpu_ptr(&ovs_frag_data_storage);
 794         data->dst = skb->_skb_refdst;
 795         data->vport = vport;
 796         data->cb = *OVS_CB(skb);
 797         data->inner_protocol = skb->inner_protocol;
 798         data->network_offset = orig_network_offset;
 799         if (skb_vlan_tag_present(skb))
 800                 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
 801         else
 802                 data->vlan_tci = 0;
 803         data->vlan_proto = skb->vlan_proto;
 804         data->mac_proto = mac_proto;
 805         data->l2_len = hlen;
 806         memcpy(&data->l2_data, skb->data, hlen);
 807
 808         memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 809         skb_pull(skb, hlen);
 810 }
 811
 812 static void ovs_fragment(struct net *net, struct vport *vport,
 813                          struct sk_buff *skb, u16 mru,
 814                          struct sw_flow_key *key)
 815 {
 816         u16 orig_network_offset = 0;
 817
 818         if (eth_p_mpls(skb->protocol)) {
 819                 orig_network_offset = skb_network_offset(skb);
 820                 skb->network_header = skb->inner_network_header;
 821         }
 822
 823         if (skb_network_offset(skb) > MAX_L2_LEN) {
 824                 OVS_NLERR(1, "L2 header too long to fragment");
 825                 goto err;
 826         }
 827
 828         if (key->eth.type == htons(ETH_P_IP)) {
 829                 struct dst_entry ovs_dst;
 830                 unsigned long orig_dst;
 831
 832                 prepare_frag(vport, skb, orig_network_offset,
 833                              ovs_key_mac_proto(key));
 834                 dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1,
 835                          DST_OBSOLETE_NONE, DST_NOCOUNT);
 836                 ovs_dst.dev = vport->dev;
 837
 838                 orig_dst = skb->_skb_refdst;
 839                 skb_dst_set_noref(skb, &ovs_dst);
 840                 IPCB(skb)->frag_max_size = mru;
 841
 842                 ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
 843                 refdst_drop(orig_dst);
 844         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 845                 const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
 846                 unsigned long orig_dst;
 847                 struct rt6_info ovs_rt;
 848
 849                 if (!v6ops)
 850                         goto err;
 851
 852                 prepare_frag(vport, skb, orig_network_offset,
 853                              ovs_key_mac_proto(key));
 854                 memset(&ovs_rt, 0, sizeof(ovs_rt));
 855                 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
 856                          DST_OBSOLETE_NONE, DST_NOCOUNT);
 857                 ovs_rt.dst.dev = vport->dev;
 858
 859                 orig_dst = skb->_skb_refdst;
 860                 skb_dst_set_noref(skb, &ovs_rt.dst);
 861                 IP6CB(skb)->frag_max_size = mru;
 862
 863                 v6ops->fragment(net, skb->sk, skb, ovs_vport_output);
 864                 refdst_drop(orig_dst);
 865         } else {
 866                 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
 867                           ovs_vport_name(vport), ntohs(key->eth.type), mru,
 868                           vport->dev->mtu);
 869                 goto err;
 870         }
 871
 872         return;
 873 err:
 874         kfree_skb(skb);
 875 }
 876
 877 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
 878                       struct sw_flow_key *key)
 879 {
 880         struct vport *vport = ovs_vport_rcu(dp, out_port);
 881
 882         if (likely(vport)) {
 883                 u16 mru = OVS_CB(skb)->mru;
 884                 u32 cutlen = OVS_CB(skb)->cutlen;
 885
 886                 if (unlikely(cutlen > 0)) {
 887                         if (skb->len - cutlen > ovs_mac_header_len(key))
 888                                 pskb_trim(skb, skb->len - cutlen);
 889                         else
 890                                 pskb_trim(skb, ovs_mac_header_len(key));
 891                 }
 892
 893                 if (likely(!mru ||
 894                            (skb->len <= mru + vport->dev->hard_header_len))) {
 895                         ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
 896                 } else if (mru <= vport->dev->mtu) {
 897                         struct net *net = read_pnet(&dp->net);
 898
 899                         ovs_fragment(net, vport, skb, mru, key);
 900                 } else {
 901                         kfree_skb(skb);
 902                 }
 903         } else {
 904                 kfree_skb(skb);
 905         }
 906 }
 907
 908 static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 909                             struct sw_flow_key *key, const struct nlattr *attr,
 910                             const struct nlattr *actions, int actions_len,
 911                             uint32_t cutlen)
 912 {
 913         struct dp_upcall_info upcall;
 914         const struct nlattr *a;
 915         int rem;
 916
 917         memset(&upcall, 0, sizeof(upcall));
 918         upcall.cmd = OVS_PACKET_CMD_ACTION;
 919         upcall.mru = OVS_CB(skb)->mru;
 920
 921         for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 922                  a = nla_next(a, &rem)) {
 923                 switch (nla_type(a)) {
 924                 case OVS_USERSPACE_ATTR_USERDATA:
 925                         upcall.userdata = a;
 926                         break;
 927
 928                 case OVS_USERSPACE_ATTR_PID:
 929                         upcall.portid = nla_get_u32(a);
 930                         break;
 931
 932                 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
 933                         /* Get out tunnel info. */
 934                         struct vport *vport;
 935
 936                         vport = ovs_vport_rcu(dp, nla_get_u32(a));
 937                         if (vport) {
 938                                 int err;
 939
 940                                 err = dev_fill_metadata_dst(vport->dev, skb);
 941                                 if (!err)
 942                                         upcall.egress_tun_info = skb_tunnel_info(skb);
 943                         }
 944
 945                         break;
 946                 }
 947
 948                 case OVS_USERSPACE_ATTR_ACTIONS: {
 949                         /* Include actions. */
 950                         upcall.actions = actions;
 951                         upcall.actions_len = actions_len;
 952                         break;
 953                 }
 954
 955                 } /* End of switch. */
 956         }
 957
 958         return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
 959 }
 960
 961 /* When 'last' is true, sample() should always consume the 'skb'.
 962  * Otherwise, sample() should keep 'skb' intact regardless what
 963  * actions are executed within sample().
 964  */
 965 static int sample(struct datapath *dp, struct sk_buff *skb,
 966                   struct sw_flow_key *key, const struct nlattr *attr,
 967                   bool last)
 968 {
 969         struct nlattr *actions;
 970         struct nlattr *sample_arg;
 971         int rem = nla_len(attr);
 972         const struct sample_arg *arg;
 973         bool clone_flow_key;
 974
 975         /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
 976         sample_arg = nla_data(attr);
 977         arg = nla_data(sample_arg);
 978         actions = nla_next(sample_arg, &rem);
 979
 980         if ((arg->probability != U32_MAX) &&
 981             (!arg->probability || prandom_u32() > arg->probability)) {
 982                 if (last)
 983                         consume_skb(skb);
 984                 return 0;
 985         }
 986
 987         clone_flow_key = !arg->exec;
 988         return clone_execute(dp, skb, key, 0, actions, rem, last,
 989                              clone_flow_key);
 990 }
 991
 992 /* When 'last' is true, clone() should always consume the 'skb'.
 993  * Otherwise, clone() should keep 'skb' intact regardless what
 994  * actions are executed within clone().
 995  */
 996 static int clone(struct datapath *dp, struct sk_buff *skb,
 997                  struct sw_flow_key *key, const struct nlattr *attr,
 998                  bool last)
 999 {
1000         struct nlattr *actions;
1001         struct nlattr *clone_arg;
1002         int rem = nla_len(attr);
1003         bool dont_clone_flow_key;
1004
1005         /* The first action is always 'OVS_CLONE_ATTR_ARG'. */
1006         clone_arg = nla_data(attr);
1007         dont_clone_flow_key = nla_get_u32(clone_arg);
1008         actions = nla_next(clone_arg, &rem);
1009
1010         return clone_execute(dp, skb, key, 0, actions, rem, last,
1011                              !dont_clone_flow_key);
1012 }
1013
1014 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
1015                          const struct nlattr *attr)
1016 {
1017         struct ovs_action_hash *hash_act = nla_data(attr);
1018         u32 hash = 0;
1019
1020         /* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
1021         hash = skb_get_hash(skb);
1022         hash = jhash_1word(hash, hash_act->hash_basis);
1023         if (!hash)
1024                 hash = 0x1;
1025
1026         key->ovs_flow_hash = hash;
1027 }
1028
1029 static int execute_set_action(struct sk_buff *skb,
1030                               struct sw_flow_key *flow_key,
1031                               const struct nlattr *a)
1032 {
1033         /* Only tunnel set execution is supported without a mask. */
1034         if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1035                 struct ovs_tunnel_info *tun = nla_data(a);
1036
1037                 skb_dst_drop(skb);
1038                 dst_hold((struct dst_entry *)tun->tun_dst);
1039                 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
1040                 return 0;
1041         }
1042
1043         return -EINVAL;
1044 }
1045
1046 /* Mask is at the midpoint of the data. */
1047 #define get_mask(a, type) ((const type)nla_data(a) + 1)
1048
1049 static int execute_masked_set_action(struct sk_buff *skb,
1050                                      struct sw_flow_key *flow_key,
1051                                      const struct nlattr *a)
1052 {
1053         int err = 0;
1054
1055         switch (nla_type(a)) {
1056         case OVS_KEY_ATTR_PRIORITY:
1057                 OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1058                                *get_mask(a, u32 *));
1059                 flow_key->phy.priority = skb->priority;
1060                 break;
1061
1062         case OVS_KEY_ATTR_SKB_MARK:
1063                 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1064                 flow_key->phy.skb_mark = skb->mark;
1065                 break;
1066
1067         case OVS_KEY_ATTR_TUNNEL_INFO:
1068                 /* Masked data not supported for tunnel. */
1069                 err = -EINVAL;
1070                 break;
1071
1072         case OVS_KEY_ATTR_ETHERNET:
1073                 err = set_eth_addr(skb, flow_key, nla_data(a),
1074                                    get_mask(a, struct ovs_key_ethernet *));
1075                 break;
1076
1077         case OVS_KEY_ATTR_NSH:
1078                 err = set_nsh(skb, flow_key, a);
1079                 break;
1080
1081         case OVS_KEY_ATTR_IPV4:
1082                 err = set_ipv4(skb, flow_key, nla_data(a),
1083                                get_mask(a, struct ovs_key_ipv4 *));
1084                 break;
1085
1086         case OVS_KEY_ATTR_IPV6:
1087                 err = set_ipv6(skb, flow_key, nla_data(a),
1088                                get_mask(a, struct ovs_key_ipv6 *));
1089                 break;
1090
1091         case OVS_KEY_ATTR_TCP:
1092                 err = set_tcp(skb, flow_key, nla_data(a),
1093                               get_mask(a, struct ovs_key_tcp *));
1094                 break;
1095
1096         case OVS_KEY_ATTR_UDP:
1097                 err = set_udp(skb, flow_key, nla_data(a),
1098                               get_mask(a, struct ovs_key_udp *));
1099                 break;
1100
1101         case OVS_KEY_ATTR_SCTP:
1102                 err = set_sctp(skb, flow_key, nla_data(a),
1103                                get_mask(a, struct ovs_key_sctp *));
1104                 break;
1105
1106         case OVS_KEY_ATTR_MPLS:
1107                 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1108                                                                     __be32 *));
1109                 break;
1110
1111         case OVS_KEY_ATTR_CT_STATE:
1112         case OVS_KEY_ATTR_CT_ZONE:
1113         case OVS_KEY_ATTR_CT_MARK:
1114         case OVS_KEY_ATTR_CT_LABELS:
1115         case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1116         case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1117                 err = -EINVAL;
1118                 break;
1119         }
1120
1121         return err;
1122 }
1123
1124 static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1125                           struct sw_flow_key *key,
1126                           const struct nlattr *a, bool last)
1127 {
1128         u32 recirc_id;
1129
1130         if (!is_flow_key_valid(key)) {
1131                 int err;
1132
1133                 err = ovs_flow_key_update(skb, key);
1134                 if (err)
1135                         return err;
1136         }
1137         BUG_ON(!is_flow_key_valid(key));
1138
1139         recirc_id = nla_get_u32(a);
1140         return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
1141 }
1142
1143 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
1144                                  struct sw_flow_key *key,
1145                                  const struct nlattr *attr, bool last)
1146 {
1147         const struct nlattr *actions, *cpl_arg;
1148         const struct check_pkt_len_arg *arg;
1149         int rem = nla_len(attr);
1150         bool clone_flow_key;
1151
1152         /* The first netlink attribute in 'attr' is always
1153          * 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
1154          */
1155         cpl_arg = nla_data(attr);
1156         arg = nla_data(cpl_arg);
1157
1158         if (skb->len <= arg->pkt_len) {
1159                 /* Second netlink attribute in 'attr' is always
1160                  * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
1161                  */
1162                 actions = nla_next(cpl_arg, &rem);
1163                 clone_flow_key = !arg->exec_for_lesser_equal;
1164         } else {
1165                 /* Third netlink attribute in 'attr' is always
1166                  * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
1167                  */
1168                 actions = nla_next(cpl_arg, &rem);
1169                 actions = nla_next(actions, &rem);
1170                 clone_flow_key = !arg->exec_for_greater;
1171         }
1172
1173         return clone_execute(dp, skb, key, 0, nla_data(actions),
1174                              nla_len(actions), last, clone_flow_key);
1175 }
1176
1177 /* Execute a list of actions against 'skb'. */
1178 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1179                               struct sw_flow_key *key,
1180                               const struct nlattr *attr, int len)
1181 {
1182         const struct nlattr *a;
1183         int rem;
1184
1185         for (a = attr, rem = len; rem > 0;
1186              a = nla_next(a, &rem)) {
1187                 int err = 0;
1188
1189                 switch (nla_type(a)) {
1190                 case OVS_ACTION_ATTR_OUTPUT: {
1191                         int port = nla_get_u32(a);
1192                         struct sk_buff *clone;
1193
1194                         /* Every output action needs a separate clone
1195                          * of 'skb', In case the output action is the
1196                          * last action, cloning can be avoided.
1197                          */
1198                         if (nla_is_last(a, rem)) {
1199                                 do_output(dp, skb, port, key);
1200                                 /* 'skb' has been used for output.
1201                                  */
1202                                 return 0;
1203                         }
1204
1205                         clone = skb_clone(skb, GFP_ATOMIC);
1206                         if (clone)
1207                                 do_output(dp, clone, port, key);
1208                         OVS_CB(skb)->cutlen = 0;
1209                         break;
1210                 }
1211
1212                 case OVS_ACTION_ATTR_TRUNC: {
1213                         struct ovs_action_trunc *trunc = nla_data(a);
1214
1215                         if (skb->len > trunc->max_len)
1216                                 OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1217                         break;
1218                 }
1219
1220                 case OVS_ACTION_ATTR_USERSPACE:
1221                         output_userspace(dp, skb, key, a, attr,
1222                                                      len, OVS_CB(skb)->cutlen);
1223                         OVS_CB(skb)->cutlen = 0;
1224                         break;
1225
1226                 case OVS_ACTION_ATTR_HASH:
1227                         execute_hash(skb, key, a);
1228                         break;
1229
1230                 case OVS_ACTION_ATTR_PUSH_MPLS:
1231                         err = push_mpls(skb, key, nla_data(a));
1232                         break;
1233
1234                 case OVS_ACTION_ATTR_POP_MPLS:
1235                         err = pop_mpls(skb, key, nla_get_be16(a));
1236                         break;
1237
1238                 case OVS_ACTION_ATTR_PUSH_VLAN:
1239                         err = push_vlan(skb, key, nla_data(a));
1240                         break;
1241
1242                 case OVS_ACTION_ATTR_POP_VLAN:
1243                         err = pop_vlan(skb, key);
1244                         break;
1245
1246                 case OVS_ACTION_ATTR_RECIRC: {
1247                         bool last = nla_is_last(a, rem);
1248
1249                         err = execute_recirc(dp, skb, key, a, last);
1250                         if (last) {
1251                                 /* If this is the last action, the skb has
1252                                  * been consumed or freed.
1253                                  * Return immediately.
1254                                  */
1255                                 return err;
1256                         }
1257                         break;
1258                 }
1259
1260                 case OVS_ACTION_ATTR_SET:
1261                         err = execute_set_action(skb, key, nla_data(a));
1262                         break;
1263
1264                 case OVS_ACTION_ATTR_SET_MASKED:
1265                 case OVS_ACTION_ATTR_SET_TO_MASKED:
1266                         err = execute_masked_set_action(skb, key, nla_data(a));
1267                         break;
1268
1269                 case OVS_ACTION_ATTR_SAMPLE: {
1270                         bool last = nla_is_last(a, rem);
1271
1272                         err = sample(dp, skb, key, a, last);
1273                         if (last)
1274                                 return err;
1275
1276                         break;
1277                 }
1278
1279                 case OVS_ACTION_ATTR_CT:
1280                         if (!is_flow_key_valid(key)) {
1281                                 err = ovs_flow_key_update(skb, key);
1282                                 if (err)
1283                                         return err;
1284                         }
1285
1286                         err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1287                                              nla_data(a));
1288
1289                         /* Hide stolen IP fragments from user space. */
1290                         if (err)
1291                                 return err == -EINPROGRESS ? 0 : err;
1292                         break;
1293
1294                 case OVS_ACTION_ATTR_CT_CLEAR:
1295                         err = ovs_ct_clear(skb, key);
1296                         break;
1297
1298                 case OVS_ACTION_ATTR_PUSH_ETH:
1299                         err = push_eth(skb, key, nla_data(a));
1300                         break;
1301
1302                 case OVS_ACTION_ATTR_POP_ETH:
1303                         err = pop_eth(skb, key);
1304                         break;
1305
1306                 case OVS_ACTION_ATTR_PUSH_NSH: {
1307                         u8 buffer[NSH_HDR_MAX_LEN];
1308                         struct nshhdr *nh = (struct nshhdr *)buffer;
1309
1310                         err = nsh_hdr_from_nlattr(nla_data(a), nh,
1311                                                   NSH_HDR_MAX_LEN);
1312                         if (unlikely(err))
1313                                 break;
1314                         err = push_nsh(skb, key, nh);
1315                         break;
1316                 }
1317
1318                 case OVS_ACTION_ATTR_POP_NSH:
1319                         err = pop_nsh(skb, key);
1320                         break;
1321
1322                 case OVS_ACTION_ATTR_METER:
1323                         if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
1324                                 consume_skb(skb);
1325                                 return 0;
1326                         }
1327                         break;
1328
1329                 case OVS_ACTION_ATTR_CLONE: {
1330                         bool last = nla_is_last(a, rem);
1331
1332                         err = clone(dp, skb, key, a, last);
1333                         if (last)
1334                                 return err;
1335
1336                         break;
1337                 }
1338
1339                 case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
1340                         bool last = nla_is_last(a, rem);
1341
1342                         err = execute_check_pkt_len(dp, skb, key, a, last);
1343                         if (last)
1344                                 return err;
1345
1346                         break;
1347                 }
1348                 }
1349
1350                 if (unlikely(err)) {
1351                         kfree_skb(skb);
1352                         return err;
1353                 }
1354         }
1355
1356         consume_skb(skb);
1357         return 0;
1358 }
1359
1360 /* Execute the actions on the clone of the packet. The effect of the
1361  * execution does not affect the original 'skb' nor the original 'key'.
1362  *
1363  * The execution may be deferred in case the actions can not be executed
1364  * immediately.
1365  */
1366 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1367                          struct sw_flow_key *key, u32 recirc_id,
1368                          const struct nlattr *actions, int len,
1369                          bool last, bool clone_flow_key)
1370 {
1371         struct deferred_action *da;
1372         struct sw_flow_key *clone;
1373
1374         skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1375         if (!skb) {
1376                 /* Out of memory, skip this action.
1377                  */
1378                 return 0;
1379         }
1380
1381         /* When clone_flow_key is false, the 'key' will not be change
1382          * by the actions, then the 'key' can be used directly.
1383          * Otherwise, try to clone key from the next recursion level of
1384          * 'flow_keys'. If clone is successful, execute the actions
1385          * without deferring.
1386          */
1387         clone = clone_flow_key ? clone_key(key) : key;
1388         if (clone) {
1389                 int err = 0;
1390
1391                 if (actions) { /* Sample action */
1392                         if (clone_flow_key)
1393                                 __this_cpu_inc(exec_actions_level);
1394
1395                         err = do_execute_actions(dp, skb, clone,
1396                                                  actions, len);
1397
1398                         if (clone_flow_key)
1399                                 __this_cpu_dec(exec_actions_level);
1400                 } else { /* Recirc action */
1401                         clone->recirc_id = recirc_id;
1402                         ovs_dp_process_packet(skb, clone);
1403                 }
1404                 return err;
1405         }
1406
1407         /* Out of 'flow_keys' space. Defer actions */
1408         da = add_deferred_actions(skb, key, actions, len);
1409         if (da) {
1410                 if (!actions) { /* Recirc action */
1411                         key = &da->pkt_key;
1412                         key->recirc_id = recirc_id;
1413                 }
1414         } else {
1415                 /* Out of per CPU action FIFO space. Drop the 'skb' and
1416                  * log an error.
1417                  */
1418                 kfree_skb(skb);
1419
1420                 if (net_ratelimit()) {
1421                         if (actions) { /* Sample action */
1422                                 pr_warn("%s: deferred action limit reached, drop sample action\n",
1423                                         ovs_dp_name(dp));
1424                         } else {  /* Recirc action */
1425                                 pr_warn("%s: deferred action limit reached, drop recirc action\n",
1426                                         ovs_dp_name(dp));
1427                         }
1428                 }
1429         }
1430         return 0;
1431 }
1432
1433 static void process_deferred_actions(struct datapath *dp)
1434 {
1435         struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1436
1437         /* Do not touch the FIFO in case there is no deferred actions. */
1438         if (action_fifo_is_empty(fifo))
1439                 return;
1440
1441         /* Finishing executing all deferred actions. */
1442         do {
1443                 struct deferred_action *da = action_fifo_get(fifo);
1444                 struct sk_buff *skb = da->skb;
1445                 struct sw_flow_key *key = &da->pkt_key;
1446                 const struct nlattr *actions = da->actions;
1447                 int actions_len = da->actions_len;
1448
1449                 if (actions)
1450                         do_execute_actions(dp, skb, key, actions, actions_len);
1451                 else
1452                         ovs_dp_process_packet(skb, key);
1453         } while (!action_fifo_is_empty(fifo));
1454
1455         /* Reset FIFO for the next packet.  */
1456         action_fifo_init(fifo);
1457 }
1458
1459 /* Execute a list of actions against 'skb'. */
1460 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1461                         const struct sw_flow_actions *acts,
1462                         struct sw_flow_key *key)
1463 {
1464         int err, level;
1465
1466         level = __this_cpu_inc_return(exec_actions_level);
1467         if (unlikely(level > OVS_RECURSION_LIMIT)) {
1468                 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1469                                      ovs_dp_name(dp));
1470                 kfree_skb(skb);
1471                 err = -ENETDOWN;
1472                 goto out;
1473         }
1474
1475         OVS_CB(skb)->acts_origlen = acts->orig_len;
1476         err = do_execute_actions(dp, skb, key,
1477                                  acts->actions, acts->actions_len);
1478
1479         if (level == 1)
1480                 process_deferred_actions(dp);
1481
1482 out:
1483         __this_cpu_dec(exec_actions_level);
1484         return err;
1485 }
1486
1487 int action_fifos_init(void)
1488 {
1489         action_fifos = alloc_percpu(struct action_fifo);
1490         if (!action_fifos)
1491                 return -ENOMEM;
1492
1493         flow_keys = alloc_percpu(struct action_flow_keys);
1494         if (!flow_keys) {
1495                 free_percpu(action_fifos);
1496                 return -ENOMEM;
1497         }
1498
1499         return 0;
1500 }
1501
1502 void action_fifos_exit(void)
1503 {
1504         free_percpu(action_fifos);
1505         free_percpu(flow_keys);
1506 }