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/sctp.h>
  13 #include <linux/tcp.h>
  14 #include <linux/udp.h>
  15 #include <linux/in6.h>
  16 #include <linux/if_arp.h>
  17 #include <linux/if_vlan.h>
  18
  19 #include <net/dst.h>
  20 #include <net/gso.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
  28 #if IS_ENABLED(CONFIG_PSAMPLE)
  29 #include <net/psample.h>
  30 #endif
  31
  32 #include <net/sctp/checksum.h>
  33
  34 #include "datapath.h"
  35 #include "drop.h"
  36 #include "flow.h"
  37 #include "conntrack.h"
  38 #include "vport.h"
  39 #include "flow_netlink.h"
  40 #include "openvswitch_trace.h"
  41
  42 struct deferred_action {
  43         struct sk_buff *skb;
  44         const struct nlattr *actions;
  45         int actions_len;
  46
  47         /* Store pkt_key clone when creating deferred action. */
  48         struct sw_flow_key pkt_key;
  49 };
  50
  51 #define MAX_L2_LEN      (VLAN_ETH_HLEN + 3 * MPLS_HLEN)
  52 struct ovs_frag_data {
  53         unsigned long dst;
  54         struct vport *vport;
  55         struct ovs_skb_cb cb;
  56         __be16 inner_protocol;
  57         u16 network_offset;     /* valid only for MPLS */
  58         u16 vlan_tci;
  59         __be16 vlan_proto;
  60         unsigned int l2_len;
  61         u8 mac_proto;
  62         u8 l2_data[MAX_L2_LEN];
  63 };
  64
  65 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
  66
  67 #define DEFERRED_ACTION_FIFO_SIZE 10
  68 #define OVS_RECURSION_LIMIT 5
  69 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
  70 struct action_fifo {
  71         int head;
  72         int tail;
  73         /* Deferred action fifo queue storage. */
  74         struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
  75 };
  76
  77 struct action_flow_keys {
  78         struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
  79 };
  80
  81 static struct action_fifo __percpu *action_fifos;
  82 static struct action_flow_keys __percpu *flow_keys;
  83 static DEFINE_PER_CPU(int, exec_actions_level);
  84
  85 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
  86  * space. Return NULL if out of key spaces.
  87  */
  88 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
  89 {
  90         struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
  91         int level = this_cpu_read(exec_actions_level);
  92         struct sw_flow_key *key = NULL;
  93
  94         if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
  95                 key = &keys->key[level - 1];
  96                 *key = *key_;
  97         }
  98
  99         return key;
 100 }
 101
 102 static void action_fifo_init(struct action_fifo *fifo)
 103 {
 104         fifo->head = 0;
 105         fifo->tail = 0;
 106 }
 107
 108 static bool action_fifo_is_empty(const struct action_fifo *fifo)
 109 {
 110         return (fifo->head == fifo->tail);
 111 }
 112
 113 static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
 114 {
 115         if (action_fifo_is_empty(fifo))
 116                 return NULL;
 117
 118         return &fifo->fifo[fifo->tail++];
 119 }
 120
 121 static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
 122 {
 123         if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
 124                 return NULL;
 125
 126         return &fifo->fifo[fifo->head++];
 127 }
 128
 129 /* Return true if fifo is not full */
 130 static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
 131                                     const struct sw_flow_key *key,
 132                                     const struct nlattr *actions,
 133                                     const int actions_len)
 134 {
 135         struct action_fifo *fifo;
 136         struct deferred_action *da;
 137
 138         fifo = this_cpu_ptr(action_fifos);
 139         da = action_fifo_put(fifo);
 140         if (da) {
 141                 da->skb = skb;
 142                 da->actions = actions;
 143                 da->actions_len = actions_len;
 144                 da->pkt_key = *key;
 145         }
 146
 147         return da;
 148 }
 149
 150 static void invalidate_flow_key(struct sw_flow_key *key)
 151 {
 152         key->mac_proto |= SW_FLOW_KEY_INVALID;
 153 }
 154
 155 static bool is_flow_key_valid(const struct sw_flow_key *key)
 156 {
 157         return !(key->mac_proto & SW_FLOW_KEY_INVALID);
 158 }
 159
 160 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
 161                          struct sw_flow_key *key,
 162                          u32 recirc_id,
 163                          const struct nlattr *actions, int len,
 164                          bool last, bool clone_flow_key);
 165
 166 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 167                               struct sw_flow_key *key,
 168                               const struct nlattr *attr, int len);
 169
 170 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 171                      __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len)
 172 {
 173         int err;
 174
 175         err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len);
 176         if (err)
 177                 return err;
 178
 179         if (!mac_len)
 180                 key->mac_proto = MAC_PROTO_NONE;
 181
 182         invalidate_flow_key(key);
 183         return 0;
 184 }
 185
 186 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 187                     const __be16 ethertype)
 188 {
 189         int err;
 190
 191         err = skb_mpls_pop(skb, ethertype, skb->mac_len,
 192                            ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET);
 193         if (err)
 194                 return err;
 195
 196         if (ethertype == htons(ETH_P_TEB))
 197                 key->mac_proto = MAC_PROTO_ETHERNET;
 198
 199         invalidate_flow_key(key);
 200         return 0;
 201 }
 202
 203 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 204                     const __be32 *mpls_lse, const __be32 *mask)
 205 {
 206         struct mpls_shim_hdr *stack;
 207         __be32 lse;
 208         int err;
 209
 210         if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN))
 211                 return -ENOMEM;
 212
 213         stack = mpls_hdr(skb);
 214         lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
 215         err = skb_mpls_update_lse(skb, lse);
 216         if (err)
 217                 return err;
 218
 219         flow_key->mpls.lse[0] = lse;
 220         return 0;
 221 }
 222
 223 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 224 {
 225         int err;
 226
 227         err = skb_vlan_pop(skb);
 228         if (skb_vlan_tag_present(skb)) {
 229                 invalidate_flow_key(key);
 230         } else {
 231                 key->eth.vlan.tci = 0;
 232                 key->eth.vlan.tpid = 0;
 233         }
 234         return err;
 235 }
 236
 237 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 238                      const struct ovs_action_push_vlan *vlan)
 239 {
 240         int err;
 241
 242         if (skb_vlan_tag_present(skb)) {
 243                 invalidate_flow_key(key);
 244         } else {
 245                 key->eth.vlan.tci = vlan->vlan_tci;
 246                 key->eth.vlan.tpid = vlan->vlan_tpid;
 247         }
 248         err = skb_vlan_push(skb, vlan->vlan_tpid,
 249                             ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
 250         skb_reset_mac_len(skb);
 251         return err;
 252 }
 253
 254 /* 'src' is already properly masked. */
 255 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 256 {
 257         u16 *dst = (u16 *)dst_;
 258         const u16 *src = (const u16 *)src_;
 259         const u16 *mask = (const u16 *)mask_;
 260
 261         OVS_SET_MASKED(dst[0], src[0], mask[0]);
 262         OVS_SET_MASKED(dst[1], src[1], mask[1]);
 263         OVS_SET_MASKED(dst[2], src[2], mask[2]);
 264 }
 265
 266 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 267                         const struct ovs_key_ethernet *key,
 268                         const struct ovs_key_ethernet *mask)
 269 {
 270         int err;
 271
 272         err = skb_ensure_writable(skb, ETH_HLEN);
 273         if (unlikely(err))
 274                 return err;
 275
 276         skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 277
 278         ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 279                                mask->eth_src);
 280         ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 281                                mask->eth_dst);
 282
 283         skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 284
 285         ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 286         ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 287         return 0;
 288 }
 289
 290 /* pop_eth does not support VLAN packets as this action is never called
 291  * for them.
 292  */
 293 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
 294 {
 295         int err;
 296
 297         err = skb_eth_pop(skb);
 298         if (err)
 299                 return err;
 300
 301         /* safe right before invalidate_flow_key */
 302         key->mac_proto = MAC_PROTO_NONE;
 303         invalidate_flow_key(key);
 304         return 0;
 305 }
 306
 307 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
 308                     const struct ovs_action_push_eth *ethh)
 309 {
 310         int err;
 311
 312         err = skb_eth_push(skb, ethh->addresses.eth_dst,
 313                            ethh->addresses.eth_src);
 314         if (err)
 315                 return err;
 316
 317         /* safe right before invalidate_flow_key */
 318         key->mac_proto = MAC_PROTO_ETHERNET;
 319         invalidate_flow_key(key);
 320         return 0;
 321 }
 322
 323 static noinline_for_stack int push_nsh(struct sk_buff *skb,
 324                                        struct sw_flow_key *key,
 325                                        const struct nlattr *a)
 326 {
 327         u8 buffer[NSH_HDR_MAX_LEN];
 328         struct nshhdr *nh = (struct nshhdr *)buffer;
 329         int err;
 330
 331         err = nsh_hdr_from_nlattr(a, nh, NSH_HDR_MAX_LEN);
 332         if (err)
 333                 return err;
 334
 335         err = nsh_push(skb, nh);
 336         if (err)
 337                 return err;
 338
 339         /* safe right before invalidate_flow_key */
 340         key->mac_proto = MAC_PROTO_NONE;
 341         invalidate_flow_key(key);
 342         return 0;
 343 }
 344
 345 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 346 {
 347         int err;
 348
 349         err = nsh_pop(skb);
 350         if (err)
 351                 return err;
 352
 353         /* safe right before invalidate_flow_key */
 354         if (skb->protocol == htons(ETH_P_TEB))
 355                 key->mac_proto = MAC_PROTO_ETHERNET;
 356         else
 357                 key->mac_proto = MAC_PROTO_NONE;
 358         invalidate_flow_key(key);
 359         return 0;
 360 }
 361
 362 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
 363                                   __be32 addr, __be32 new_addr)
 364 {
 365         int transport_len = skb->len - skb_transport_offset(skb);
 366
 367         if (nh->frag_off & htons(IP_OFFSET))
 368                 return;
 369
 370         if (nh->protocol == IPPROTO_TCP) {
 371                 if (likely(transport_len >= sizeof(struct tcphdr)))
 372                         inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 373                                                  addr, new_addr, true);
 374         } else if (nh->protocol == IPPROTO_UDP) {
 375                 if (likely(transport_len >= sizeof(struct udphdr))) {
 376                         struct udphdr *uh = udp_hdr(skb);
 377
 378                         if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 379                                 inet_proto_csum_replace4(&uh->check, skb,
 380                                                          addr, new_addr, true);
 381                                 if (!uh->check)
 382                                         uh->check = CSUM_MANGLED_0;
 383                         }
 384                 }
 385         }
 386 }
 387
 388 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 389                         __be32 *addr, __be32 new_addr)
 390 {
 391         update_ip_l4_checksum(skb, nh, *addr, new_addr);
 392         csum_replace4(&nh->check, *addr, new_addr);
 393         skb_clear_hash(skb);
 394         ovs_ct_clear(skb, NULL);
 395         *addr = new_addr;
 396 }
 397
 398 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 399                                  __be32 addr[4], const __be32 new_addr[4])
 400 {
 401         int transport_len = skb->len - skb_transport_offset(skb);
 402
 403         if (l4_proto == NEXTHDR_TCP) {
 404                 if (likely(transport_len >= sizeof(struct tcphdr)))
 405                         inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 406                                                   addr, new_addr, true);
 407         } else if (l4_proto == NEXTHDR_UDP) {
 408                 if (likely(transport_len >= sizeof(struct udphdr))) {
 409                         struct udphdr *uh = udp_hdr(skb);
 410
 411                         if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 412                                 inet_proto_csum_replace16(&uh->check, skb,
 413                                                           addr, new_addr, true);
 414                                 if (!uh->check)
 415                                         uh->check = CSUM_MANGLED_0;
 416                         }
 417                 }
 418         } else if (l4_proto == NEXTHDR_ICMP) {
 419                 if (likely(transport_len >= sizeof(struct icmp6hdr)))
 420                         inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 421                                                   skb, addr, new_addr, true);
 422         }
 423 }
 424
 425 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 426                            const __be32 mask[4], __be32 masked[4])
 427 {
 428         masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
 429         masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
 430         masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
 431         masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
 432 }
 433
 434 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 435                           __be32 addr[4], const __be32 new_addr[4],
 436                           bool recalculate_csum)
 437 {
 438         if (recalculate_csum)
 439                 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 440
 441         skb_clear_hash(skb);
 442         ovs_ct_clear(skb, NULL);
 443         memcpy(addr, new_addr, sizeof(__be32[4]));
 444 }
 445
 446 static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask)
 447 {
 448         u8 old_ipv6_tclass = ipv6_get_dsfield(nh);
 449
 450         ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask);
 451
 452         if (skb->ip_summed == CHECKSUM_COMPLETE)
 453                 csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12),
 454                              (__force __wsum)(ipv6_tclass << 12));
 455
 456         ipv6_change_dsfield(nh, ~mask, ipv6_tclass);
 457 }
 458
 459 static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask)
 460 {
 461         u32 ofl;
 462
 463         ofl = nh->flow_lbl[0] << 16 |  nh->flow_lbl[1] << 8 |  nh->flow_lbl[2];
 464         fl = OVS_MASKED(ofl, fl, mask);
 465
 466         /* Bits 21-24 are always unmasked, so this retains their values. */
 467         nh->flow_lbl[0] = (u8)(fl >> 16);
 468         nh->flow_lbl[1] = (u8)(fl >> 8);
 469         nh->flow_lbl[2] = (u8)fl;
 470
 471         if (skb->ip_summed == CHECKSUM_COMPLETE)
 472                 csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl));
 473 }
 474
 475 static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask)
 476 {
 477         new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask);
 478
 479         if (skb->ip_summed == CHECKSUM_COMPLETE)
 480                 csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8),
 481                              (__force __wsum)(new_ttl << 8));
 482         nh->hop_limit = new_ttl;
 483 }
 484
 485 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 486                        u8 mask)
 487 {
 488         new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
 489
 490         csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 491         nh->ttl = new_ttl;
 492 }
 493
 494 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 495                     const struct ovs_key_ipv4 *key,
 496                     const struct ovs_key_ipv4 *mask)
 497 {
 498         struct iphdr *nh;
 499         __be32 new_addr;
 500         int err;
 501
 502         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 503                                   sizeof(struct iphdr));
 504         if (unlikely(err))
 505                 return err;
 506
 507         nh = ip_hdr(skb);
 508
 509         /* Setting an IP addresses is typically only a side effect of
 510          * matching on them in the current userspace implementation, so it
 511          * makes sense to check if the value actually changed.
 512          */
 513         if (mask->ipv4_src) {
 514                 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 515
 516                 if (unlikely(new_addr != nh->saddr)) {
 517                         set_ip_addr(skb, nh, &nh->saddr, new_addr);
 518                         flow_key->ipv4.addr.src = new_addr;
 519                 }
 520         }
 521         if (mask->ipv4_dst) {
 522                 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 523
 524                 if (unlikely(new_addr != nh->daddr)) {
 525                         set_ip_addr(skb, nh, &nh->daddr, new_addr);
 526                         flow_key->ipv4.addr.dst = new_addr;
 527                 }
 528         }
 529         if (mask->ipv4_tos) {
 530                 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 531                 flow_key->ip.tos = nh->tos;
 532         }
 533         if (mask->ipv4_ttl) {
 534                 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 535                 flow_key->ip.ttl = nh->ttl;
 536         }
 537
 538         return 0;
 539 }
 540
 541 static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 542 {
 543         return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 544 }
 545
 546 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 547                     const struct ovs_key_ipv6 *key,
 548                     const struct ovs_key_ipv6 *mask)
 549 {
 550         struct ipv6hdr *nh;
 551         int err;
 552
 553         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 554                                   sizeof(struct ipv6hdr));
 555         if (unlikely(err))
 556                 return err;
 557
 558         nh = ipv6_hdr(skb);
 559
 560         /* Setting an IP addresses is typically only a side effect of
 561          * matching on them in the current userspace implementation, so it
 562          * makes sense to check if the value actually changed.
 563          */
 564         if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 565                 __be32 *saddr = (__be32 *)&nh->saddr;
 566                 __be32 masked[4];
 567
 568                 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 569
 570                 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 571                         set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
 572                                       true);
 573                         memcpy(&flow_key->ipv6.addr.src, masked,
 574                                sizeof(flow_key->ipv6.addr.src));
 575                 }
 576         }
 577         if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 578                 unsigned int offset = 0;
 579                 int flags = IP6_FH_F_SKIP_RH;
 580                 bool recalc_csum = true;
 581                 __be32 *daddr = (__be32 *)&nh->daddr;
 582                 __be32 masked[4];
 583
 584                 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 585
 586                 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 587                         if (ipv6_ext_hdr(nh->nexthdr))
 588                                 recalc_csum = (ipv6_find_hdr(skb, &offset,
 589                                                              NEXTHDR_ROUTING,
 590                                                              NULL, &flags)
 591                                                != NEXTHDR_ROUTING);
 592
 593                         set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
 594                                       recalc_csum);
 595                         memcpy(&flow_key->ipv6.addr.dst, masked,
 596                                sizeof(flow_key->ipv6.addr.dst));
 597                 }
 598         }
 599         if (mask->ipv6_tclass) {
 600                 set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass);
 601                 flow_key->ip.tos = ipv6_get_dsfield(nh);
 602         }
 603         if (mask->ipv6_label) {
 604                 set_ipv6_fl(skb, nh, ntohl(key->ipv6_label),
 605                             ntohl(mask->ipv6_label));
 606                 flow_key->ipv6.label =
 607                     *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 608         }
 609         if (mask->ipv6_hlimit) {
 610                 set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit);
 611                 flow_key->ip.ttl = nh->hop_limit;
 612         }
 613         return 0;
 614 }
 615
 616 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
 617                    const struct nlattr *a)
 618 {
 619         struct nshhdr *nh;
 620         size_t length;
 621         int err;
 622         u8 flags;
 623         u8 ttl;
 624         int i;
 625
 626         struct ovs_key_nsh key;
 627         struct ovs_key_nsh mask;
 628
 629         err = nsh_key_from_nlattr(a, &key, &mask);
 630         if (err)
 631                 return err;
 632
 633         /* Make sure the NSH base header is there */
 634         if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
 635                 return -ENOMEM;
 636
 637         nh = nsh_hdr(skb);
 638         length = nsh_hdr_len(nh);
 639
 640         /* Make sure the whole NSH header is there */
 641         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 642                                        length);
 643         if (unlikely(err))
 644                 return err;
 645
 646         nh = nsh_hdr(skb);
 647         skb_postpull_rcsum(skb, nh, length);
 648         flags = nsh_get_flags(nh);
 649         flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
 650         flow_key->nsh.base.flags = flags;
 651         ttl = nsh_get_ttl(nh);
 652         ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
 653         flow_key->nsh.base.ttl = ttl;
 654         nsh_set_flags_and_ttl(nh, flags, ttl);
 655         nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
 656                                   mask.base.path_hdr);
 657         flow_key->nsh.base.path_hdr = nh->path_hdr;
 658         switch (nh->mdtype) {
 659         case NSH_M_TYPE1:
 660                 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
 661                         nh->md1.context[i] =
 662                             OVS_MASKED(nh->md1.context[i], key.context[i],
 663                                        mask.context[i]);
 664                 }
 665                 memcpy(flow_key->nsh.context, nh->md1.context,
 666                        sizeof(nh->md1.context));
 667                 break;
 668         case NSH_M_TYPE2:
 669                 memset(flow_key->nsh.context, 0,
 670                        sizeof(flow_key->nsh.context));
 671                 break;
 672         default:
 673                 return -EINVAL;
 674         }
 675         skb_postpush_rcsum(skb, nh, length);
 676         return 0;
 677 }
 678
 679 /* Must follow skb_ensure_writable() since that can move the skb data. */
 680 static void set_tp_port(struct sk_buff *skb, __be16 *port,
 681                         __be16 new_port, __sum16 *check)
 682 {
 683         ovs_ct_clear(skb, NULL);
 684         inet_proto_csum_replace2(check, skb, *port, new_port, false);
 685         *port = new_port;
 686 }
 687
 688 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 689                    const struct ovs_key_udp *key,
 690                    const struct ovs_key_udp *mask)
 691 {
 692         struct udphdr *uh;
 693         __be16 src, dst;
 694         int err;
 695
 696         err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 697                                   sizeof(struct udphdr));
 698         if (unlikely(err))
 699                 return err;
 700
 701         uh = udp_hdr(skb);
 702         /* Either of the masks is non-zero, so do not bother checking them. */
 703         src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
 704         dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 705
 706         if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 707                 if (likely(src != uh->source)) {
 708                         set_tp_port(skb, &uh->source, src, &uh->check);
 709                         flow_key->tp.src = src;
 710                 }
 711                 if (likely(dst != uh->dest)) {
 712                         set_tp_port(skb, &uh->dest, dst, &uh->check);
 713                         flow_key->tp.dst = dst;
 714                 }
 715
 716                 if (unlikely(!uh->check))
 717                         uh->check = CSUM_MANGLED_0;
 718         } else {
 719                 uh->source = src;
 720                 uh->dest = dst;
 721                 flow_key->tp.src = src;
 722                 flow_key->tp.dst = dst;
 723                 ovs_ct_clear(skb, NULL);
 724         }
 725
 726         skb_clear_hash(skb);
 727
 728         return 0;
 729 }
 730
 731 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 732                    const struct ovs_key_tcp *key,
 733                    const struct ovs_key_tcp *mask)
 734 {
 735         struct tcphdr *th;
 736         __be16 src, dst;
 737         int err;
 738
 739         err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 740                                   sizeof(struct tcphdr));
 741         if (unlikely(err))
 742                 return err;
 743
 744         th = tcp_hdr(skb);
 745         src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
 746         if (likely(src != th->source)) {
 747                 set_tp_port(skb, &th->source, src, &th->check);
 748                 flow_key->tp.src = src;
 749         }
 750         dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 751         if (likely(dst != th->dest)) {
 752                 set_tp_port(skb, &th->dest, dst, &th->check);
 753                 flow_key->tp.dst = dst;
 754         }
 755         skb_clear_hash(skb);
 756
 757         return 0;
 758 }
 759
 760 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 761                     const struct ovs_key_sctp *key,
 762                     const struct ovs_key_sctp *mask)
 763 {
 764         unsigned int sctphoff = skb_transport_offset(skb);
 765         struct sctphdr *sh;
 766         __le32 old_correct_csum, new_csum, old_csum;
 767         int err;
 768
 769         err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 770         if (unlikely(err))
 771                 return err;
 772
 773         sh = sctp_hdr(skb);
 774         old_csum = sh->checksum;
 775         old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 776
 777         sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
 778         sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 779
 780         new_csum = sctp_compute_cksum(skb, sctphoff);
 781
 782         /* Carry any checksum errors through. */
 783         sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 784
 785         skb_clear_hash(skb);
 786         ovs_ct_clear(skb, NULL);
 787
 788         flow_key->tp.src = sh->source;
 789         flow_key->tp.dst = sh->dest;
 790
 791         return 0;
 792 }
 793
 794 static int ovs_vport_output(struct net *net, struct sock *sk,
 795                             struct sk_buff *skb)
 796 {
 797         struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
 798         struct vport *vport = data->vport;
 799
 800         if (skb_cow_head(skb, data->l2_len) < 0) {
 801                 kfree_skb_reason(skb, SKB_DROP_REASON_NOMEM);
 802                 return -ENOMEM;
 803         }
 804
 805         __skb_dst_copy(skb, data->dst);
 806         *OVS_CB(skb) = data->cb;
 807         skb->inner_protocol = data->inner_protocol;
 808         if (data->vlan_tci & VLAN_CFI_MASK)
 809                 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK);
 810         else
 811                 __vlan_hwaccel_clear_tag(skb);
 812
 813         /* Reconstruct the MAC header.  */
 814         skb_push(skb, data->l2_len);
 815         memcpy(skb->data, &data->l2_data, data->l2_len);
 816         skb_postpush_rcsum(skb, skb->data, data->l2_len);
 817         skb_reset_mac_header(skb);
 818
 819         if (eth_p_mpls(skb->protocol)) {
 820                 skb->inner_network_header = skb->network_header;
 821                 skb_set_network_header(skb, data->network_offset);
 822                 skb_reset_mac_len(skb);
 823         }
 824
 825         ovs_vport_send(vport, skb, data->mac_proto);
 826         return 0;
 827 }
 828
 829 static unsigned int
 830 ovs_dst_get_mtu(const struct dst_entry *dst)
 831 {
 832         return dst->dev->mtu;
 833 }
 834
 835 static struct dst_ops ovs_dst_ops = {
 836         .family = AF_UNSPEC,
 837         .mtu = ovs_dst_get_mtu,
 838 };
 839
 840 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 841  * ovs_vport_output(), which is called once per fragmented packet.
 842  */
 843 static void prepare_frag(struct vport *vport, struct sk_buff *skb,
 844                          u16 orig_network_offset, u8 mac_proto)
 845 {
 846         unsigned int hlen = skb_network_offset(skb);
 847         struct ovs_frag_data *data;
 848
 849         data = this_cpu_ptr(&ovs_frag_data_storage);
 850         data->dst = skb->_skb_refdst;
 851         data->vport = vport;
 852         data->cb = *OVS_CB(skb);
 853         data->inner_protocol = skb->inner_protocol;
 854         data->network_offset = orig_network_offset;
 855         if (skb_vlan_tag_present(skb))
 856                 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
 857         else
 858                 data->vlan_tci = 0;
 859         data->vlan_proto = skb->vlan_proto;
 860         data->mac_proto = mac_proto;
 861         data->l2_len = hlen;
 862         memcpy(&data->l2_data, skb->data, hlen);
 863
 864         memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 865         skb_pull(skb, hlen);
 866 }
 867
 868 static void ovs_fragment(struct net *net, struct vport *vport,
 869                          struct sk_buff *skb, u16 mru,
 870                          struct sw_flow_key *key)
 871 {
 872         enum ovs_drop_reason reason;
 873         u16 orig_network_offset = 0;
 874
 875         if (eth_p_mpls(skb->protocol)) {
 876                 orig_network_offset = skb_network_offset(skb);
 877                 skb->network_header = skb->inner_network_header;
 878         }
 879
 880         if (skb_network_offset(skb) > MAX_L2_LEN) {
 881                 OVS_NLERR(1, "L2 header too long to fragment");
 882                 reason = OVS_DROP_FRAG_L2_TOO_LONG;
 883                 goto err;
 884         }
 885
 886         if (key->eth.type == htons(ETH_P_IP)) {
 887                 struct rtable ovs_rt = { 0 };
 888                 unsigned long orig_dst;
 889
 890                 prepare_frag(vport, skb, orig_network_offset,
 891                              ovs_key_mac_proto(key));
 892                 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL,
 893                          DST_OBSOLETE_NONE, DST_NOCOUNT);
 894                 ovs_rt.dst.dev = vport->dev;
 895
 896                 orig_dst = skb->_skb_refdst;
 897                 skb_dst_set_noref(skb, &ovs_rt.dst);
 898                 IPCB(skb)->frag_max_size = mru;
 899
 900                 ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
 901                 refdst_drop(orig_dst);
 902         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 903                 unsigned long orig_dst;
 904                 struct rt6_info ovs_rt;
 905
 906                 prepare_frag(vport, skb, orig_network_offset,
 907                              ovs_key_mac_proto(key));
 908                 memset(&ovs_rt, 0, sizeof(ovs_rt));
 909                 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL,
 910                          DST_OBSOLETE_NONE, DST_NOCOUNT);
 911                 ovs_rt.dst.dev = vport->dev;
 912
 913                 orig_dst = skb->_skb_refdst;
 914                 skb_dst_set_noref(skb, &ovs_rt.dst);
 915                 IP6CB(skb)->frag_max_size = mru;
 916
 917                 ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output);
 918                 refdst_drop(orig_dst);
 919         } else {
 920                 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
 921                           ovs_vport_name(vport), ntohs(key->eth.type), mru,
 922                           vport->dev->mtu);
 923                 reason = OVS_DROP_FRAG_INVALID_PROTO;
 924                 goto err;
 925         }
 926
 927         return;
 928 err:
 929         ovs_kfree_skb_reason(skb, reason);
 930 }
 931
 932 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
 933                       struct sw_flow_key *key)
 934 {
 935         struct vport *vport = ovs_vport_rcu(dp, out_port);
 936
 937         if (likely(vport && netif_carrier_ok(vport->dev))) {
 938                 u16 mru = OVS_CB(skb)->mru;
 939                 u32 cutlen = OVS_CB(skb)->cutlen;
 940
 941                 if (unlikely(cutlen > 0)) {
 942                         if (skb->len - cutlen > ovs_mac_header_len(key))
 943                                 pskb_trim(skb, skb->len - cutlen);
 944                         else
 945                                 pskb_trim(skb, ovs_mac_header_len(key));
 946                 }
 947
 948                 /* Need to set the pkt_type to involve the routing layer.  The
 949                  * packet movement through the OVS datapath doesn't generally
 950                  * use routing, but this is needed for tunnel cases.
 951                  */
 952                 skb->pkt_type = PACKET_OUTGOING;
 953
 954                 if (likely(!mru ||
 955                            (skb->len <= mru + vport->dev->hard_header_len))) {
 956                         ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
 957                 } else if (mru <= vport->dev->mtu) {
 958                         struct net *net = read_pnet(&dp->net);
 959
 960                         ovs_fragment(net, vport, skb, mru, key);
 961                 } else {
 962                         kfree_skb_reason(skb, SKB_DROP_REASON_PKT_TOO_BIG);
 963                 }
 964         } else {
 965                 kfree_skb_reason(skb, SKB_DROP_REASON_DEV_READY);
 966         }
 967 }
 968
 969 static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 970                             struct sw_flow_key *key, const struct nlattr *attr,
 971                             const struct nlattr *actions, int actions_len,
 972                             uint32_t cutlen)
 973 {
 974         struct dp_upcall_info upcall;
 975         const struct nlattr *a;
 976         int rem;
 977
 978         memset(&upcall, 0, sizeof(upcall));
 979         upcall.cmd = OVS_PACKET_CMD_ACTION;
 980         upcall.mru = OVS_CB(skb)->mru;
 981
 982         for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 983              a = nla_next(a, &rem)) {
 984                 switch (nla_type(a)) {
 985                 case OVS_USERSPACE_ATTR_USERDATA:
 986                         upcall.userdata = a;
 987                         break;
 988
 989                 case OVS_USERSPACE_ATTR_PID:
 990                         if (dp->user_features &
 991                             OVS_DP_F_DISPATCH_UPCALL_PER_CPU)
 992                                 upcall.portid =
 993                                   ovs_dp_get_upcall_portid(dp,
 994                                                            smp_processor_id());
 995                         else
 996                                 upcall.portid = nla_get_u32(a);
 997                         break;
 998
 999                 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
1000                         /* Get out tunnel info. */
1001                         struct vport *vport;
1002
1003                         vport = ovs_vport_rcu(dp, nla_get_u32(a));
1004                         if (vport) {
1005                                 int err;
1006
1007                                 err = dev_fill_metadata_dst(vport->dev, skb);
1008                                 if (!err)
1009                                         upcall.egress_tun_info = skb_tunnel_info(skb);
1010                         }
1011
1012                         break;
1013                 }
1014
1015                 case OVS_USERSPACE_ATTR_ACTIONS: {
1016                         /* Include actions. */
1017                         upcall.actions = actions;
1018                         upcall.actions_len = actions_len;
1019                         break;
1020                 }
1021
1022                 } /* End of switch. */
1023         }
1024
1025         return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
1026 }
1027
1028 static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb,
1029                                      struct sw_flow_key *key,
1030                                      const struct nlattr *attr)
1031 {
1032         /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */
1033         struct nlattr *actions = nla_data(attr);
1034
1035         if (nla_len(actions))
1036                 return clone_execute(dp, skb, key, 0, nla_data(actions),
1037                                      nla_len(actions), true, false);
1038
1039         ovs_kfree_skb_reason(skb, OVS_DROP_IP_TTL);
1040         return 0;
1041 }
1042
1043 /* When 'last' is true, sample() should always consume the 'skb'.
1044  * Otherwise, sample() should keep 'skb' intact regardless what
1045  * actions are executed within sample().
1046  */
1047 static int sample(struct datapath *dp, struct sk_buff *skb,
1048                   struct sw_flow_key *key, const struct nlattr *attr,
1049                   bool last)
1050 {
1051         struct nlattr *actions;
1052         struct nlattr *sample_arg;
1053         int rem = nla_len(attr);
1054         const struct sample_arg *arg;
1055         u32 init_probability;
1056         bool clone_flow_key;
1057         int err;
1058
1059         /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
1060         sample_arg = nla_data(attr);
1061         arg = nla_data(sample_arg);
1062         actions = nla_next(sample_arg, &rem);
1063         init_probability = OVS_CB(skb)->probability;
1064
1065         if ((arg->probability != U32_MAX) &&
1066             (!arg->probability || get_random_u32() > arg->probability)) {
1067                 if (last)
1068                         ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION);
1069                 return 0;
1070         }
1071
1072         OVS_CB(skb)->probability = arg->probability;
1073
1074         clone_flow_key = !arg->exec;
1075         err = clone_execute(dp, skb, key, 0, actions, rem, last,
1076                             clone_flow_key);
1077
1078         if (!last)
1079                 OVS_CB(skb)->probability = init_probability;
1080
1081         return err;
1082 }
1083
1084 /* When 'last' is true, clone() should always consume the 'skb'.
1085  * Otherwise, clone() should keep 'skb' intact regardless what
1086  * actions are executed within clone().
1087  */
1088 static int clone(struct datapath *dp, struct sk_buff *skb,
1089                  struct sw_flow_key *key, const struct nlattr *attr,
1090                  bool last)
1091 {
1092         struct nlattr *actions;
1093         struct nlattr *clone_arg;
1094         int rem = nla_len(attr);
1095         bool dont_clone_flow_key;
1096
1097         /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */
1098         clone_arg = nla_data(attr);
1099         dont_clone_flow_key = nla_get_u32(clone_arg);
1100         actions = nla_next(clone_arg, &rem);
1101
1102         return clone_execute(dp, skb, key, 0, actions, rem, last,
1103                              !dont_clone_flow_key);
1104 }
1105
1106 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
1107                          const struct nlattr *attr)
1108 {
1109         struct ovs_action_hash *hash_act = nla_data(attr);
1110         u32 hash = 0;
1111
1112         if (hash_act->hash_alg == OVS_HASH_ALG_L4) {
1113                 /* OVS_HASH_ALG_L4 hasing type. */
1114                 hash = skb_get_hash(skb);
1115         } else if (hash_act->hash_alg == OVS_HASH_ALG_SYM_L4) {
1116                 /* OVS_HASH_ALG_SYM_L4 hashing type.  NOTE: this doesn't
1117                  * extend past an encapsulated header.
1118                  */
1119                 hash = __skb_get_hash_symmetric(skb);
1120         }
1121
1122         hash = jhash_1word(hash, hash_act->hash_basis);
1123         if (!hash)
1124                 hash = 0x1;
1125
1126         key->ovs_flow_hash = hash;
1127 }
1128
1129 static int execute_set_action(struct sk_buff *skb,
1130                               struct sw_flow_key *flow_key,
1131                               const struct nlattr *a)
1132 {
1133         /* Only tunnel set execution is supported without a mask. */
1134         if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1135                 struct ovs_tunnel_info *tun = nla_data(a);
1136
1137                 skb_dst_drop(skb);
1138                 dst_hold((struct dst_entry *)tun->tun_dst);
1139                 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
1140                 return 0;
1141         }
1142
1143         return -EINVAL;
1144 }
1145
1146 /* Mask is at the midpoint of the data. */
1147 #define get_mask(a, type) ((const type)nla_data(a) + 1)
1148
1149 static int execute_masked_set_action(struct sk_buff *skb,
1150                                      struct sw_flow_key *flow_key,
1151                                      const struct nlattr *a)
1152 {
1153         int err = 0;
1154
1155         switch (nla_type(a)) {
1156         case OVS_KEY_ATTR_PRIORITY:
1157                 OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1158                                *get_mask(a, u32 *));
1159                 flow_key->phy.priority = skb->priority;
1160                 break;
1161
1162         case OVS_KEY_ATTR_SKB_MARK:
1163                 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1164                 flow_key->phy.skb_mark = skb->mark;
1165                 break;
1166
1167         case OVS_KEY_ATTR_TUNNEL_INFO:
1168                 /* Masked data not supported for tunnel. */
1169                 err = -EINVAL;
1170                 break;
1171
1172         case OVS_KEY_ATTR_ETHERNET:
1173                 err = set_eth_addr(skb, flow_key, nla_data(a),
1174                                    get_mask(a, struct ovs_key_ethernet *));
1175                 break;
1176
1177         case OVS_KEY_ATTR_NSH:
1178                 err = set_nsh(skb, flow_key, a);
1179                 break;
1180
1181         case OVS_KEY_ATTR_IPV4:
1182                 err = set_ipv4(skb, flow_key, nla_data(a),
1183                                get_mask(a, struct ovs_key_ipv4 *));
1184                 break;
1185
1186         case OVS_KEY_ATTR_IPV6:
1187                 err = set_ipv6(skb, flow_key, nla_data(a),
1188                                get_mask(a, struct ovs_key_ipv6 *));
1189                 break;
1190
1191         case OVS_KEY_ATTR_TCP:
1192                 err = set_tcp(skb, flow_key, nla_data(a),
1193                               get_mask(a, struct ovs_key_tcp *));
1194                 break;
1195
1196         case OVS_KEY_ATTR_UDP:
1197                 err = set_udp(skb, flow_key, nla_data(a),
1198                               get_mask(a, struct ovs_key_udp *));
1199                 break;
1200
1201         case OVS_KEY_ATTR_SCTP:
1202                 err = set_sctp(skb, flow_key, nla_data(a),
1203                                get_mask(a, struct ovs_key_sctp *));
1204                 break;
1205
1206         case OVS_KEY_ATTR_MPLS:
1207                 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1208                                                                     __be32 *));
1209                 break;
1210
1211         case OVS_KEY_ATTR_CT_STATE:
1212         case OVS_KEY_ATTR_CT_ZONE:
1213         case OVS_KEY_ATTR_CT_MARK:
1214         case OVS_KEY_ATTR_CT_LABELS:
1215         case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1216         case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1217                 err = -EINVAL;
1218                 break;
1219         }
1220
1221         return err;
1222 }
1223
1224 static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1225                           struct sw_flow_key *key,
1226                           const struct nlattr *a, bool last)
1227 {
1228         u32 recirc_id;
1229
1230         if (!is_flow_key_valid(key)) {
1231                 int err;
1232
1233                 err = ovs_flow_key_update(skb, key);
1234                 if (err)
1235                         return err;
1236         }
1237         BUG_ON(!is_flow_key_valid(key));
1238
1239         recirc_id = nla_get_u32(a);
1240         return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
1241 }
1242
1243 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
1244                                  struct sw_flow_key *key,
1245                                  const struct nlattr *attr, bool last)
1246 {
1247         struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
1248         const struct nlattr *actions, *cpl_arg;
1249         int len, max_len, rem = nla_len(attr);
1250         const struct check_pkt_len_arg *arg;
1251         bool clone_flow_key;
1252
1253         /* The first netlink attribute in 'attr' is always
1254          * 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
1255          */
1256         cpl_arg = nla_data(attr);
1257         arg = nla_data(cpl_arg);
1258
1259         len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
1260         max_len = arg->pkt_len;
1261
1262         if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) ||
1263             len <= max_len) {
1264                 /* Second netlink attribute in 'attr' is always
1265                  * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
1266                  */
1267                 actions = nla_next(cpl_arg, &rem);
1268                 clone_flow_key = !arg->exec_for_lesser_equal;
1269         } else {
1270                 /* Third netlink attribute in 'attr' is always
1271                  * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
1272                  */
1273                 actions = nla_next(cpl_arg, &rem);
1274                 actions = nla_next(actions, &rem);
1275                 clone_flow_key = !arg->exec_for_greater;
1276         }
1277
1278         return clone_execute(dp, skb, key, 0, nla_data(actions),
1279                              nla_len(actions), last, clone_flow_key);
1280 }
1281
1282 static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key)
1283 {
1284         int err;
1285
1286         if (skb->protocol == htons(ETH_P_IPV6)) {
1287                 struct ipv6hdr *nh;
1288
1289                 err = skb_ensure_writable(skb, skb_network_offset(skb) +
1290                                           sizeof(*nh));
1291                 if (unlikely(err))
1292                         return err;
1293
1294                 nh = ipv6_hdr(skb);
1295
1296                 if (nh->hop_limit <= 1)
1297                         return -EHOSTUNREACH;
1298
1299                 key->ip.ttl = --nh->hop_limit;
1300         } else if (skb->protocol == htons(ETH_P_IP)) {
1301                 struct iphdr *nh;
1302                 u8 old_ttl;
1303
1304                 err = skb_ensure_writable(skb, skb_network_offset(skb) +
1305                                           sizeof(*nh));
1306                 if (unlikely(err))
1307                         return err;
1308
1309                 nh = ip_hdr(skb);
1310                 if (nh->ttl <= 1)
1311                         return -EHOSTUNREACH;
1312
1313                 old_ttl = nh->ttl--;
1314                 csum_replace2(&nh->check, htons(old_ttl << 8),
1315                               htons(nh->ttl << 8));
1316                 key->ip.ttl = nh->ttl;
1317         }
1318         return 0;
1319 }
1320
1321 #if IS_ENABLED(CONFIG_PSAMPLE)
1322 static void execute_psample(struct datapath *dp, struct sk_buff *skb,
1323                             const struct nlattr *attr)
1324 {
1325         struct psample_group psample_group = {};
1326         struct psample_metadata md = {};
1327         const struct nlattr *a;
1328         u32 rate;
1329         int rem;
1330
1331         nla_for_each_attr(a, nla_data(attr), nla_len(attr), rem) {
1332                 switch (nla_type(a)) {
1333                 case OVS_PSAMPLE_ATTR_GROUP:
1334                         psample_group.group_num = nla_get_u32(a);
1335                         break;
1336
1337                 case OVS_PSAMPLE_ATTR_COOKIE:
1338                         md.user_cookie = nla_data(a);
1339                         md.user_cookie_len = nla_len(a);
1340                         break;
1341                 }
1342         }
1343
1344         psample_group.net = ovs_dp_get_net(dp);
1345         md.in_ifindex = OVS_CB(skb)->input_vport->dev->ifindex;
1346         md.trunc_size = skb->len - OVS_CB(skb)->cutlen;
1347         md.rate_as_probability = 1;
1348
1349         rate = OVS_CB(skb)->probability ? OVS_CB(skb)->probability : U32_MAX;
1350
1351         psample_sample_packet(&psample_group, skb, rate, &md);
1352 }
1353 #else
1354 static void execute_psample(struct datapath *dp, struct sk_buff *skb,
1355                             const struct nlattr *attr)
1356 {}
1357 #endif
1358
1359 /* Execute a list of actions against 'skb'. */
1360 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1361                               struct sw_flow_key *key,
1362                               const struct nlattr *attr, int len)
1363 {
1364         const struct nlattr *a;
1365         int rem;
1366
1367         for (a = attr, rem = len; rem > 0;
1368              a = nla_next(a, &rem)) {
1369                 int err = 0;
1370
1371                 if (trace_ovs_do_execute_action_enabled())
1372                         trace_ovs_do_execute_action(dp, skb, key, a, rem);
1373
1374                 /* Actions that rightfully have to consume the skb should do it
1375                  * and return directly.
1376                  */
1377                 switch (nla_type(a)) {
1378                 case OVS_ACTION_ATTR_OUTPUT: {
1379                         int port = nla_get_u32(a);
1380                         struct sk_buff *clone;
1381
1382                         /* Every output action needs a separate clone
1383                          * of 'skb', In case the output action is the
1384                          * last action, cloning can be avoided.
1385                          */
1386                         if (nla_is_last(a, rem)) {
1387                                 do_output(dp, skb, port, key);
1388                                 /* 'skb' has been used for output.
1389                                  */
1390                                 return 0;
1391                         }
1392
1393                         clone = skb_clone(skb, GFP_ATOMIC);
1394                         if (clone)
1395                                 do_output(dp, clone, port, key);
1396                         OVS_CB(skb)->cutlen = 0;
1397                         break;
1398                 }
1399
1400                 case OVS_ACTION_ATTR_TRUNC: {
1401                         struct ovs_action_trunc *trunc = nla_data(a);
1402
1403                         if (skb->len > trunc->max_len)
1404                                 OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1405                         break;
1406                 }
1407
1408                 case OVS_ACTION_ATTR_USERSPACE:
1409                         output_userspace(dp, skb, key, a, attr,
1410                                                      len, OVS_CB(skb)->cutlen);
1411                         OVS_CB(skb)->cutlen = 0;
1412                         if (nla_is_last(a, rem)) {
1413                                 consume_skb(skb);
1414                                 return 0;
1415                         }
1416                         break;
1417
1418                 case OVS_ACTION_ATTR_HASH:
1419                         execute_hash(skb, key, a);
1420                         break;
1421
1422                 case OVS_ACTION_ATTR_PUSH_MPLS: {
1423                         struct ovs_action_push_mpls *mpls = nla_data(a);
1424
1425                         err = push_mpls(skb, key, mpls->mpls_lse,
1426                                         mpls->mpls_ethertype, skb->mac_len);
1427                         break;
1428                 }
1429                 case OVS_ACTION_ATTR_ADD_MPLS: {
1430                         struct ovs_action_add_mpls *mpls = nla_data(a);
1431                         __u16 mac_len = 0;
1432
1433                         if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK)
1434                                 mac_len = skb->mac_len;
1435
1436                         err = push_mpls(skb, key, mpls->mpls_lse,
1437                                         mpls->mpls_ethertype, mac_len);
1438                         break;
1439                 }
1440                 case OVS_ACTION_ATTR_POP_MPLS:
1441                         err = pop_mpls(skb, key, nla_get_be16(a));
1442                         break;
1443
1444                 case OVS_ACTION_ATTR_PUSH_VLAN:
1445                         err = push_vlan(skb, key, nla_data(a));
1446                         break;
1447
1448                 case OVS_ACTION_ATTR_POP_VLAN:
1449                         err = pop_vlan(skb, key);
1450                         break;
1451
1452                 case OVS_ACTION_ATTR_RECIRC: {
1453                         bool last = nla_is_last(a, rem);
1454
1455                         err = execute_recirc(dp, skb, key, a, last);
1456                         if (last) {
1457                                 /* If this is the last action, the skb has
1458                                  * been consumed or freed.
1459                                  * Return immediately.
1460                                  */
1461                                 return err;
1462                         }
1463                         break;
1464                 }
1465
1466                 case OVS_ACTION_ATTR_SET:
1467                         err = execute_set_action(skb, key, nla_data(a));
1468                         break;
1469
1470                 case OVS_ACTION_ATTR_SET_MASKED:
1471                 case OVS_ACTION_ATTR_SET_TO_MASKED:
1472                         err = execute_masked_set_action(skb, key, nla_data(a));
1473                         break;
1474
1475                 case OVS_ACTION_ATTR_SAMPLE: {
1476                         bool last = nla_is_last(a, rem);
1477
1478                         err = sample(dp, skb, key, a, last);
1479                         if (last)
1480                                 return err;
1481
1482                         break;
1483                 }
1484
1485                 case OVS_ACTION_ATTR_CT:
1486                         if (!is_flow_key_valid(key)) {
1487                                 err = ovs_flow_key_update(skb, key);
1488                                 if (err)
1489                                         return err;
1490                         }
1491
1492                         err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1493                                              nla_data(a));
1494
1495                         /* Hide stolen IP fragments from user space. */
1496                         if (err)
1497                                 return err == -EINPROGRESS ? 0 : err;
1498                         break;
1499
1500                 case OVS_ACTION_ATTR_CT_CLEAR:
1501                         err = ovs_ct_clear(skb, key);
1502                         break;
1503
1504                 case OVS_ACTION_ATTR_PUSH_ETH:
1505                         err = push_eth(skb, key, nla_data(a));
1506                         break;
1507
1508                 case OVS_ACTION_ATTR_POP_ETH:
1509                         err = pop_eth(skb, key);
1510                         break;
1511
1512                 case OVS_ACTION_ATTR_PUSH_NSH:
1513                         err = push_nsh(skb, key, nla_data(a));
1514                         break;
1515
1516                 case OVS_ACTION_ATTR_POP_NSH:
1517                         err = pop_nsh(skb, key);
1518                         break;
1519
1520                 case OVS_ACTION_ATTR_METER:
1521                         if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
1522                                 ovs_kfree_skb_reason(skb, OVS_DROP_METER);
1523                                 return 0;
1524                         }
1525                         break;
1526
1527                 case OVS_ACTION_ATTR_CLONE: {
1528                         bool last = nla_is_last(a, rem);
1529
1530                         err = clone(dp, skb, key, a, last);
1531                         if (last)
1532                                 return err;
1533
1534                         break;
1535                 }
1536
1537                 case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
1538                         bool last = nla_is_last(a, rem);
1539
1540                         err = execute_check_pkt_len(dp, skb, key, a, last);
1541                         if (last)
1542                                 return err;
1543
1544                         break;
1545                 }
1546
1547                 case OVS_ACTION_ATTR_DEC_TTL:
1548                         err = execute_dec_ttl(skb, key);
1549                         if (err == -EHOSTUNREACH)
1550                                 return dec_ttl_exception_handler(dp, skb,
1551                                                                  key, a);
1552                         break;
1553
1554                 case OVS_ACTION_ATTR_DROP: {
1555                         enum ovs_drop_reason reason = nla_get_u32(a)
1556                                 ? OVS_DROP_EXPLICIT_WITH_ERROR
1557                                 : OVS_DROP_EXPLICIT;
1558
1559                         ovs_kfree_skb_reason(skb, reason);
1560                         return 0;
1561                 }
1562
1563                 case OVS_ACTION_ATTR_PSAMPLE:
1564                         execute_psample(dp, skb, a);
1565                         OVS_CB(skb)->cutlen = 0;
1566                         if (nla_is_last(a, rem)) {
1567                                 consume_skb(skb);
1568                                 return 0;
1569                         }
1570                         break;
1571                 }
1572
1573                 if (unlikely(err)) {
1574                         ovs_kfree_skb_reason(skb, OVS_DROP_ACTION_ERROR);
1575                         return err;
1576                 }
1577         }
1578
1579         ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION);
1580         return 0;
1581 }
1582
1583 /* Execute the actions on the clone of the packet. The effect of the
1584  * execution does not affect the original 'skb' nor the original 'key'.
1585  *
1586  * The execution may be deferred in case the actions can not be executed
1587  * immediately.
1588  */
1589 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1590                          struct sw_flow_key *key, u32 recirc_id,
1591                          const struct nlattr *actions, int len,
1592                          bool last, bool clone_flow_key)
1593 {
1594         struct deferred_action *da;
1595         struct sw_flow_key *clone;
1596
1597         skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1598         if (!skb) {
1599                 /* Out of memory, skip this action.
1600                  */
1601                 return 0;
1602         }
1603
1604         /* When clone_flow_key is false, the 'key' will not be change
1605          * by the actions, then the 'key' can be used directly.
1606          * Otherwise, try to clone key from the next recursion level of
1607          * 'flow_keys'. If clone is successful, execute the actions
1608          * without deferring.
1609          */
1610         clone = clone_flow_key ? clone_key(key) : key;
1611         if (clone) {
1612                 int err = 0;
1613
1614                 if (actions) { /* Sample action */
1615                         if (clone_flow_key)
1616                                 __this_cpu_inc(exec_actions_level);
1617
1618                         err = do_execute_actions(dp, skb, clone,
1619                                                  actions, len);
1620
1621                         if (clone_flow_key)
1622                                 __this_cpu_dec(exec_actions_level);
1623                 } else { /* Recirc action */
1624                         clone->recirc_id = recirc_id;
1625                         ovs_dp_process_packet(skb, clone);
1626                 }
1627                 return err;
1628         }
1629
1630         /* Out of 'flow_keys' space. Defer actions */
1631         da = add_deferred_actions(skb, key, actions, len);
1632         if (da) {
1633                 if (!actions) { /* Recirc action */
1634                         key = &da->pkt_key;
1635                         key->recirc_id = recirc_id;
1636                 }
1637         } else {
1638                 /* Out of per CPU action FIFO space. Drop the 'skb' and
1639                  * log an error.
1640                  */
1641                 ovs_kfree_skb_reason(skb, OVS_DROP_DEFERRED_LIMIT);
1642
1643                 if (net_ratelimit()) {
1644                         if (actions) { /* Sample action */
1645                                 pr_warn("%s: deferred action limit reached, drop sample action\n",
1646                                         ovs_dp_name(dp));
1647                         } else {  /* Recirc action */
1648                                 pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n",
1649                                         ovs_dp_name(dp), recirc_id);
1650                         }
1651                 }
1652         }
1653         return 0;
1654 }
1655
1656 static void process_deferred_actions(struct datapath *dp)
1657 {
1658         struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1659
1660         /* Do not touch the FIFO in case there is no deferred actions. */
1661         if (action_fifo_is_empty(fifo))
1662                 return;
1663
1664         /* Finishing executing all deferred actions. */
1665         do {
1666                 struct deferred_action *da = action_fifo_get(fifo);
1667                 struct sk_buff *skb = da->skb;
1668                 struct sw_flow_key *key = &da->pkt_key;
1669                 const struct nlattr *actions = da->actions;
1670                 int actions_len = da->actions_len;
1671
1672                 if (actions)
1673                         do_execute_actions(dp, skb, key, actions, actions_len);
1674                 else
1675                         ovs_dp_process_packet(skb, key);
1676         } while (!action_fifo_is_empty(fifo));
1677
1678         /* Reset FIFO for the next packet.  */
1679         action_fifo_init(fifo);
1680 }
1681
1682 /* Execute a list of actions against 'skb'. */
1683 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1684                         const struct sw_flow_actions *acts,
1685                         struct sw_flow_key *key)
1686 {
1687         int err, level;
1688
1689         level = __this_cpu_inc_return(exec_actions_level);
1690         if (unlikely(level > OVS_RECURSION_LIMIT)) {
1691                 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1692                                      ovs_dp_name(dp));
1693                 ovs_kfree_skb_reason(skb, OVS_DROP_RECURSION_LIMIT);
1694                 err = -ENETDOWN;
1695                 goto out;
1696         }
1697
1698         OVS_CB(skb)->acts_origlen = acts->orig_len;
1699         err = do_execute_actions(dp, skb, key,
1700                                  acts->actions, acts->actions_len);
1701
1702         if (level == 1)
1703                 process_deferred_actions(dp);
1704
1705 out:
1706         __this_cpu_dec(exec_actions_level);
1707         return err;
1708 }
1709
1710 int action_fifos_init(void)
1711 {
1712         action_fifos = alloc_percpu(struct action_fifo);
1713         if (!action_fifos)
1714                 return -ENOMEM;
1715
1716         flow_keys = alloc_percpu(struct action_flow_keys);
1717         if (!flow_keys) {
1718                 free_percpu(action_fifos);
1719                 return -ENOMEM;
1720         }
1721
1722         return 0;
1723 }
1724
1725 void action_fifos_exit(void)
1726 {
1727         free_percpu(action_fifos);
1728         free_percpu(flow_keys);
1729 }