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