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