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