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