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 *addr = new_addr; 377 } 378 379 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 380 __be32 addr[4], const __be32 new_addr[4]) 381 { 382 int transport_len = skb->len - skb_transport_offset(skb); 383 384 if (l4_proto == NEXTHDR_TCP) { 385 if (likely(transport_len >= sizeof(struct tcphdr))) 386 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 387 addr, new_addr, true); 388 } else if (l4_proto == NEXTHDR_UDP) { 389 if (likely(transport_len >= sizeof(struct udphdr))) { 390 struct udphdr *uh = udp_hdr(skb); 391 392 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 393 inet_proto_csum_replace16(&uh->check, skb, 394 addr, new_addr, true); 395 if (!uh->check) 396 uh->check = CSUM_MANGLED_0; 397 } 398 } 399 } else if (l4_proto == NEXTHDR_ICMP) { 400 if (likely(transport_len >= sizeof(struct icmp6hdr))) 401 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 402 skb, addr, new_addr, true); 403 } 404 } 405 406 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 407 const __be32 mask[4], __be32 masked[4]) 408 { 409 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 410 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 411 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 412 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 413 } 414 415 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 416 __be32 addr[4], const __be32 new_addr[4], 417 bool recalculate_csum) 418 { 419 if (recalculate_csum) 420 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 421 422 skb_clear_hash(skb); 423 memcpy(addr, new_addr, sizeof(__be32[4])); 424 } 425 426 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask) 427 { 428 /* Bits 21-24 are always unmasked, so this retains their values. */ 429 OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16)); 430 OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8)); 431 OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask); 432 } 433 434 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 435 u8 mask) 436 { 437 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 438 439 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 440 nh->ttl = new_ttl; 441 } 442 443 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 444 const struct ovs_key_ipv4 *key, 445 const struct ovs_key_ipv4 *mask) 446 { 447 struct iphdr *nh; 448 __be32 new_addr; 449 int err; 450 451 err = skb_ensure_writable(skb, skb_network_offset(skb) + 452 sizeof(struct iphdr)); 453 if (unlikely(err)) 454 return err; 455 456 nh = ip_hdr(skb); 457 458 /* Setting an IP addresses is typically only a side effect of 459 * matching on them in the current userspace implementation, so it 460 * makes sense to check if the value actually changed. 461 */ 462 if (mask->ipv4_src) { 463 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 464 465 if (unlikely(new_addr != nh->saddr)) { 466 set_ip_addr(skb, nh, &nh->saddr, new_addr); 467 flow_key->ipv4.addr.src = new_addr; 468 } 469 } 470 if (mask->ipv4_dst) { 471 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 472 473 if (unlikely(new_addr != nh->daddr)) { 474 set_ip_addr(skb, nh, &nh->daddr, new_addr); 475 flow_key->ipv4.addr.dst = new_addr; 476 } 477 } 478 if (mask->ipv4_tos) { 479 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 480 flow_key->ip.tos = nh->tos; 481 } 482 if (mask->ipv4_ttl) { 483 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 484 flow_key->ip.ttl = nh->ttl; 485 } 486 487 return 0; 488 } 489 490 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 491 { 492 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 493 } 494 495 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 496 const struct ovs_key_ipv6 *key, 497 const struct ovs_key_ipv6 *mask) 498 { 499 struct ipv6hdr *nh; 500 int err; 501 502 err = skb_ensure_writable(skb, skb_network_offset(skb) + 503 sizeof(struct ipv6hdr)); 504 if (unlikely(err)) 505 return err; 506 507 nh = ipv6_hdr(skb); 508 509 /* Setting an IP addresses is typically only a side effect of 510 * matching on them in the current userspace implementation, so it 511 * makes sense to check if the value actually changed. 512 */ 513 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 514 __be32 *saddr = (__be32 *)&nh->saddr; 515 __be32 masked[4]; 516 517 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 518 519 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 520 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 521 true); 522 memcpy(&flow_key->ipv6.addr.src, masked, 523 sizeof(flow_key->ipv6.addr.src)); 524 } 525 } 526 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 527 unsigned int offset = 0; 528 int flags = IP6_FH_F_SKIP_RH; 529 bool recalc_csum = true; 530 __be32 *daddr = (__be32 *)&nh->daddr; 531 __be32 masked[4]; 532 533 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 534 535 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 536 if (ipv6_ext_hdr(nh->nexthdr)) 537 recalc_csum = (ipv6_find_hdr(skb, &offset, 538 NEXTHDR_ROUTING, 539 NULL, &flags) 540 != NEXTHDR_ROUTING); 541 542 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 543 recalc_csum); 544 memcpy(&flow_key->ipv6.addr.dst, masked, 545 sizeof(flow_key->ipv6.addr.dst)); 546 } 547 } 548 if (mask->ipv6_tclass) { 549 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass); 550 flow_key->ip.tos = ipv6_get_dsfield(nh); 551 } 552 if (mask->ipv6_label) { 553 set_ipv6_fl(nh, ntohl(key->ipv6_label), 554 ntohl(mask->ipv6_label)); 555 flow_key->ipv6.label = 556 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 557 } 558 if (mask->ipv6_hlimit) { 559 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit, 560 mask->ipv6_hlimit); 561 flow_key->ip.ttl = nh->hop_limit; 562 } 563 return 0; 564 } 565 566 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, 567 const struct nlattr *a) 568 { 569 struct nshhdr *nh; 570 size_t length; 571 int err; 572 u8 flags; 573 u8 ttl; 574 int i; 575 576 struct ovs_key_nsh key; 577 struct ovs_key_nsh mask; 578 579 err = nsh_key_from_nlattr(a, &key, &mask); 580 if (err) 581 return err; 582 583 /* Make sure the NSH base header is there */ 584 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 585 return -ENOMEM; 586 587 nh = nsh_hdr(skb); 588 length = nsh_hdr_len(nh); 589 590 /* Make sure the whole NSH header is there */ 591 err = skb_ensure_writable(skb, skb_network_offset(skb) + 592 length); 593 if (unlikely(err)) 594 return err; 595 596 nh = nsh_hdr(skb); 597 skb_postpull_rcsum(skb, nh, length); 598 flags = nsh_get_flags(nh); 599 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 600 flow_key->nsh.base.flags = flags; 601 ttl = nsh_get_ttl(nh); 602 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); 603 flow_key->nsh.base.ttl = ttl; 604 nsh_set_flags_and_ttl(nh, flags, ttl); 605 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, 606 mask.base.path_hdr); 607 flow_key->nsh.base.path_hdr = nh->path_hdr; 608 switch (nh->mdtype) { 609 case NSH_M_TYPE1: 610 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { 611 nh->md1.context[i] = 612 OVS_MASKED(nh->md1.context[i], key.context[i], 613 mask.context[i]); 614 } 615 memcpy(flow_key->nsh.context, nh->md1.context, 616 sizeof(nh->md1.context)); 617 break; 618 case NSH_M_TYPE2: 619 memset(flow_key->nsh.context, 0, 620 sizeof(flow_key->nsh.context)); 621 break; 622 default: 623 return -EINVAL; 624 } 625 skb_postpush_rcsum(skb, nh, length); 626 return 0; 627 } 628 629 /* Must follow skb_ensure_writable() since that can move the skb data. */ 630 static void set_tp_port(struct sk_buff *skb, __be16 *port, 631 __be16 new_port, __sum16 *check) 632 { 633 inet_proto_csum_replace2(check, skb, *port, new_port, false); 634 *port = new_port; 635 } 636 637 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 638 const struct ovs_key_udp *key, 639 const struct ovs_key_udp *mask) 640 { 641 struct udphdr *uh; 642 __be16 src, dst; 643 int err; 644 645 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 646 sizeof(struct udphdr)); 647 if (unlikely(err)) 648 return err; 649 650 uh = udp_hdr(skb); 651 /* Either of the masks is non-zero, so do not bother checking them. */ 652 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 653 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 654 655 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 656 if (likely(src != uh->source)) { 657 set_tp_port(skb, &uh->source, src, &uh->check); 658 flow_key->tp.src = src; 659 } 660 if (likely(dst != uh->dest)) { 661 set_tp_port(skb, &uh->dest, dst, &uh->check); 662 flow_key->tp.dst = dst; 663 } 664 665 if (unlikely(!uh->check)) 666 uh->check = CSUM_MANGLED_0; 667 } else { 668 uh->source = src; 669 uh->dest = dst; 670 flow_key->tp.src = src; 671 flow_key->tp.dst = dst; 672 } 673 674 skb_clear_hash(skb); 675 676 return 0; 677 } 678 679 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 680 const struct ovs_key_tcp *key, 681 const struct ovs_key_tcp *mask) 682 { 683 struct tcphdr *th; 684 __be16 src, dst; 685 int err; 686 687 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 688 sizeof(struct tcphdr)); 689 if (unlikely(err)) 690 return err; 691 692 th = tcp_hdr(skb); 693 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 694 if (likely(src != th->source)) { 695 set_tp_port(skb, &th->source, src, &th->check); 696 flow_key->tp.src = src; 697 } 698 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 699 if (likely(dst != th->dest)) { 700 set_tp_port(skb, &th->dest, dst, &th->check); 701 flow_key->tp.dst = dst; 702 } 703 skb_clear_hash(skb); 704 705 return 0; 706 } 707 708 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 709 const struct ovs_key_sctp *key, 710 const struct ovs_key_sctp *mask) 711 { 712 unsigned int sctphoff = skb_transport_offset(skb); 713 struct sctphdr *sh; 714 __le32 old_correct_csum, new_csum, old_csum; 715 int err; 716 717 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 718 if (unlikely(err)) 719 return err; 720 721 sh = sctp_hdr(skb); 722 old_csum = sh->checksum; 723 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 724 725 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 726 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 727 728 new_csum = sctp_compute_cksum(skb, sctphoff); 729 730 /* Carry any checksum errors through. */ 731 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 732 733 skb_clear_hash(skb); 734 flow_key->tp.src = sh->source; 735 flow_key->tp.dst = sh->dest; 736 737 return 0; 738 } 739 740 static int ovs_vport_output(struct net *net, struct sock *sk, 741 struct sk_buff *skb) 742 { 743 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 744 struct vport *vport = data->vport; 745 746 if (skb_cow_head(skb, data->l2_len) < 0) { 747 kfree_skb(skb); 748 return -ENOMEM; 749 } 750 751 __skb_dst_copy(skb, data->dst); 752 *OVS_CB(skb) = data->cb; 753 skb->inner_protocol = data->inner_protocol; 754 if (data->vlan_tci & VLAN_CFI_MASK) 755 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); 756 else 757 __vlan_hwaccel_clear_tag(skb); 758 759 /* Reconstruct the MAC header. */ 760 skb_push(skb, data->l2_len); 761 memcpy(skb->data, &data->l2_data, data->l2_len); 762 skb_postpush_rcsum(skb, skb->data, data->l2_len); 763 skb_reset_mac_header(skb); 764 765 if (eth_p_mpls(skb->protocol)) { 766 skb->inner_network_header = skb->network_header; 767 skb_set_network_header(skb, data->network_offset); 768 skb_reset_mac_len(skb); 769 } 770 771 ovs_vport_send(vport, skb, data->mac_proto); 772 return 0; 773 } 774 775 static unsigned int 776 ovs_dst_get_mtu(const struct dst_entry *dst) 777 { 778 return dst->dev->mtu; 779 } 780 781 static struct dst_ops ovs_dst_ops = { 782 .family = AF_UNSPEC, 783 .mtu = ovs_dst_get_mtu, 784 }; 785 786 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 787 * ovs_vport_output(), which is called once per fragmented packet. 788 */ 789 static void prepare_frag(struct vport *vport, struct sk_buff *skb, 790 u16 orig_network_offset, u8 mac_proto) 791 { 792 unsigned int hlen = skb_network_offset(skb); 793 struct ovs_frag_data *data; 794 795 data = this_cpu_ptr(&ovs_frag_data_storage); 796 data->dst = skb->_skb_refdst; 797 data->vport = vport; 798 data->cb = *OVS_CB(skb); 799 data->inner_protocol = skb->inner_protocol; 800 data->network_offset = orig_network_offset; 801 if (skb_vlan_tag_present(skb)) 802 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK; 803 else 804 data->vlan_tci = 0; 805 data->vlan_proto = skb->vlan_proto; 806 data->mac_proto = mac_proto; 807 data->l2_len = hlen; 808 memcpy(&data->l2_data, skb->data, hlen); 809 810 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 811 skb_pull(skb, hlen); 812 } 813 814 static void ovs_fragment(struct net *net, struct vport *vport, 815 struct sk_buff *skb, u16 mru, 816 struct sw_flow_key *key) 817 { 818 u16 orig_network_offset = 0; 819 820 if (eth_p_mpls(skb->protocol)) { 821 orig_network_offset = skb_network_offset(skb); 822 skb->network_header = skb->inner_network_header; 823 } 824 825 if (skb_network_offset(skb) > MAX_L2_LEN) { 826 OVS_NLERR(1, "L2 header too long to fragment"); 827 goto err; 828 } 829 830 if (key->eth.type == htons(ETH_P_IP)) { 831 struct rtable ovs_rt = { 0 }; 832 unsigned long orig_dst; 833 834 prepare_frag(vport, skb, orig_network_offset, 835 ovs_key_mac_proto(key)); 836 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, 837 DST_OBSOLETE_NONE, DST_NOCOUNT); 838 ovs_rt.dst.dev = vport->dev; 839 840 orig_dst = skb->_skb_refdst; 841 skb_dst_set_noref(skb, &ovs_rt.dst); 842 IPCB(skb)->frag_max_size = mru; 843 844 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 845 refdst_drop(orig_dst); 846 } else if (key->eth.type == htons(ETH_P_IPV6)) { 847 unsigned long orig_dst; 848 struct rt6_info ovs_rt; 849 850 prepare_frag(vport, skb, orig_network_offset, 851 ovs_key_mac_proto(key)); 852 memset(&ovs_rt, 0, sizeof(ovs_rt)); 853 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, 854 DST_OBSOLETE_NONE, DST_NOCOUNT); 855 ovs_rt.dst.dev = vport->dev; 856 857 orig_dst = skb->_skb_refdst; 858 skb_dst_set_noref(skb, &ovs_rt.dst); 859 IP6CB(skb)->frag_max_size = mru; 860 861 ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output); 862 refdst_drop(orig_dst); 863 } else { 864 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 865 ovs_vport_name(vport), ntohs(key->eth.type), mru, 866 vport->dev->mtu); 867 goto err; 868 } 869 870 return; 871 err: 872 kfree_skb(skb); 873 } 874 875 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 876 struct sw_flow_key *key) 877 { 878 struct vport *vport = ovs_vport_rcu(dp, out_port); 879 880 if (likely(vport)) { 881 u16 mru = OVS_CB(skb)->mru; 882 u32 cutlen = OVS_CB(skb)->cutlen; 883 884 if (unlikely(cutlen > 0)) { 885 if (skb->len - cutlen > ovs_mac_header_len(key)) 886 pskb_trim(skb, skb->len - cutlen); 887 else 888 pskb_trim(skb, ovs_mac_header_len(key)); 889 } 890 891 if (likely(!mru || 892 (skb->len <= mru + vport->dev->hard_header_len))) { 893 ovs_vport_send(vport, skb, ovs_key_mac_proto(key)); 894 } else if (mru <= vport->dev->mtu) { 895 struct net *net = read_pnet(&dp->net); 896 897 ovs_fragment(net, vport, skb, mru, key); 898 } else { 899 kfree_skb(skb); 900 } 901 } else { 902 kfree_skb(skb); 903 } 904 } 905 906 static int output_userspace(struct datapath *dp, struct sk_buff *skb, 907 struct sw_flow_key *key, const struct nlattr *attr, 908 const struct nlattr *actions, int actions_len, 909 uint32_t cutlen) 910 { 911 struct dp_upcall_info upcall; 912 const struct nlattr *a; 913 int rem; 914 915 memset(&upcall, 0, sizeof(upcall)); 916 upcall.cmd = OVS_PACKET_CMD_ACTION; 917 upcall.mru = OVS_CB(skb)->mru; 918 919 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 920 a = nla_next(a, &rem)) { 921 switch (nla_type(a)) { 922 case OVS_USERSPACE_ATTR_USERDATA: 923 upcall.userdata = a; 924 break; 925 926 case OVS_USERSPACE_ATTR_PID: 927 if (dp->user_features & OVS_DP_F_DISPATCH_UPCALL_PER_CPU) 928 upcall.portid = 929 ovs_dp_get_upcall_portid(dp, smp_processor_id()); 930 else 931 upcall.portid = nla_get_u32(a); 932 break; 933 934 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 935 /* Get out tunnel info. */ 936 struct vport *vport; 937 938 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 939 if (vport) { 940 int err; 941 942 err = dev_fill_metadata_dst(vport->dev, skb); 943 if (!err) 944 upcall.egress_tun_info = skb_tunnel_info(skb); 945 } 946 947 break; 948 } 949 950 case OVS_USERSPACE_ATTR_ACTIONS: { 951 /* Include actions. */ 952 upcall.actions = actions; 953 upcall.actions_len = actions_len; 954 break; 955 } 956 957 } /* End of switch. */ 958 } 959 960 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 961 } 962 963 static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb, 964 struct sw_flow_key *key, 965 const struct nlattr *attr) 966 { 967 /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */ 968 struct nlattr *actions = nla_data(attr); 969 970 if (nla_len(actions)) 971 return clone_execute(dp, skb, key, 0, nla_data(actions), 972 nla_len(actions), true, false); 973 974 consume_skb(skb); 975 return 0; 976 } 977 978 /* When 'last' is true, sample() should always consume the 'skb'. 979 * Otherwise, sample() should keep 'skb' intact regardless what 980 * actions are executed within sample(). 981 */ 982 static int sample(struct datapath *dp, struct sk_buff *skb, 983 struct sw_flow_key *key, const struct nlattr *attr, 984 bool last) 985 { 986 struct nlattr *actions; 987 struct nlattr *sample_arg; 988 int rem = nla_len(attr); 989 const struct sample_arg *arg; 990 bool clone_flow_key; 991 992 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ 993 sample_arg = nla_data(attr); 994 arg = nla_data(sample_arg); 995 actions = nla_next(sample_arg, &rem); 996 997 if ((arg->probability != U32_MAX) && 998 (!arg->probability || prandom_u32() > arg->probability)) { 999 if (last) 1000 consume_skb(skb); 1001 return 0; 1002 } 1003 1004 clone_flow_key = !arg->exec; 1005 return clone_execute(dp, skb, key, 0, actions, rem, last, 1006 clone_flow_key); 1007 } 1008 1009 /* When 'last' is true, clone() should always consume the 'skb'. 1010 * Otherwise, clone() should keep 'skb' intact regardless what 1011 * actions are executed within clone(). 1012 */ 1013 static int clone(struct datapath *dp, struct sk_buff *skb, 1014 struct sw_flow_key *key, const struct nlattr *attr, 1015 bool last) 1016 { 1017 struct nlattr *actions; 1018 struct nlattr *clone_arg; 1019 int rem = nla_len(attr); 1020 bool dont_clone_flow_key; 1021 1022 /* The first action is always 'OVS_CLONE_ATTR_ARG'. */ 1023 clone_arg = nla_data(attr); 1024 dont_clone_flow_key = nla_get_u32(clone_arg); 1025 actions = nla_next(clone_arg, &rem); 1026 1027 return clone_execute(dp, skb, key, 0, actions, rem, last, 1028 !dont_clone_flow_key); 1029 } 1030 1031 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 1032 const struct nlattr *attr) 1033 { 1034 struct ovs_action_hash *hash_act = nla_data(attr); 1035 u32 hash = 0; 1036 1037 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */ 1038 hash = skb_get_hash(skb); 1039 hash = jhash_1word(hash, hash_act->hash_basis); 1040 if (!hash) 1041 hash = 0x1; 1042 1043 key->ovs_flow_hash = hash; 1044 } 1045 1046 static int execute_set_action(struct sk_buff *skb, 1047 struct sw_flow_key *flow_key, 1048 const struct nlattr *a) 1049 { 1050 /* Only tunnel set execution is supported without a mask. */ 1051 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1052 struct ovs_tunnel_info *tun = nla_data(a); 1053 1054 skb_dst_drop(skb); 1055 dst_hold((struct dst_entry *)tun->tun_dst); 1056 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 1057 return 0; 1058 } 1059 1060 return -EINVAL; 1061 } 1062 1063 /* Mask is at the midpoint of the data. */ 1064 #define get_mask(a, type) ((const type)nla_data(a) + 1) 1065 1066 static int execute_masked_set_action(struct sk_buff *skb, 1067 struct sw_flow_key *flow_key, 1068 const struct nlattr *a) 1069 { 1070 int err = 0; 1071 1072 switch (nla_type(a)) { 1073 case OVS_KEY_ATTR_PRIORITY: 1074 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 1075 *get_mask(a, u32 *)); 1076 flow_key->phy.priority = skb->priority; 1077 break; 1078 1079 case OVS_KEY_ATTR_SKB_MARK: 1080 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 1081 flow_key->phy.skb_mark = skb->mark; 1082 break; 1083 1084 case OVS_KEY_ATTR_TUNNEL_INFO: 1085 /* Masked data not supported for tunnel. */ 1086 err = -EINVAL; 1087 break; 1088 1089 case OVS_KEY_ATTR_ETHERNET: 1090 err = set_eth_addr(skb, flow_key, nla_data(a), 1091 get_mask(a, struct ovs_key_ethernet *)); 1092 break; 1093 1094 case OVS_KEY_ATTR_NSH: 1095 err = set_nsh(skb, flow_key, a); 1096 break; 1097 1098 case OVS_KEY_ATTR_IPV4: 1099 err = set_ipv4(skb, flow_key, nla_data(a), 1100 get_mask(a, struct ovs_key_ipv4 *)); 1101 break; 1102 1103 case OVS_KEY_ATTR_IPV6: 1104 err = set_ipv6(skb, flow_key, nla_data(a), 1105 get_mask(a, struct ovs_key_ipv6 *)); 1106 break; 1107 1108 case OVS_KEY_ATTR_TCP: 1109 err = set_tcp(skb, flow_key, nla_data(a), 1110 get_mask(a, struct ovs_key_tcp *)); 1111 break; 1112 1113 case OVS_KEY_ATTR_UDP: 1114 err = set_udp(skb, flow_key, nla_data(a), 1115 get_mask(a, struct ovs_key_udp *)); 1116 break; 1117 1118 case OVS_KEY_ATTR_SCTP: 1119 err = set_sctp(skb, flow_key, nla_data(a), 1120 get_mask(a, struct ovs_key_sctp *)); 1121 break; 1122 1123 case OVS_KEY_ATTR_MPLS: 1124 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1125 __be32 *)); 1126 break; 1127 1128 case OVS_KEY_ATTR_CT_STATE: 1129 case OVS_KEY_ATTR_CT_ZONE: 1130 case OVS_KEY_ATTR_CT_MARK: 1131 case OVS_KEY_ATTR_CT_LABELS: 1132 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: 1133 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: 1134 err = -EINVAL; 1135 break; 1136 } 1137 1138 return err; 1139 } 1140 1141 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1142 struct sw_flow_key *key, 1143 const struct nlattr *a, bool last) 1144 { 1145 u32 recirc_id; 1146 1147 if (!is_flow_key_valid(key)) { 1148 int err; 1149 1150 err = ovs_flow_key_update(skb, key); 1151 if (err) 1152 return err; 1153 } 1154 BUG_ON(!is_flow_key_valid(key)); 1155 1156 recirc_id = nla_get_u32(a); 1157 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); 1158 } 1159 1160 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb, 1161 struct sw_flow_key *key, 1162 const struct nlattr *attr, bool last) 1163 { 1164 struct ovs_skb_cb *ovs_cb = OVS_CB(skb); 1165 const struct nlattr *actions, *cpl_arg; 1166 int len, max_len, rem = nla_len(attr); 1167 const struct check_pkt_len_arg *arg; 1168 bool clone_flow_key; 1169 1170 /* The first netlink attribute in 'attr' is always 1171 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'. 1172 */ 1173 cpl_arg = nla_data(attr); 1174 arg = nla_data(cpl_arg); 1175 1176 len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len; 1177 max_len = arg->pkt_len; 1178 1179 if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) || 1180 len <= max_len) { 1181 /* Second netlink attribute in 'attr' is always 1182 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'. 1183 */ 1184 actions = nla_next(cpl_arg, &rem); 1185 clone_flow_key = !arg->exec_for_lesser_equal; 1186 } else { 1187 /* Third netlink attribute in 'attr' is always 1188 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'. 1189 */ 1190 actions = nla_next(cpl_arg, &rem); 1191 actions = nla_next(actions, &rem); 1192 clone_flow_key = !arg->exec_for_greater; 1193 } 1194 1195 return clone_execute(dp, skb, key, 0, nla_data(actions), 1196 nla_len(actions), last, clone_flow_key); 1197 } 1198 1199 static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) 1200 { 1201 int err; 1202 1203 if (skb->protocol == htons(ETH_P_IPV6)) { 1204 struct ipv6hdr *nh; 1205 1206 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1207 sizeof(*nh)); 1208 if (unlikely(err)) 1209 return err; 1210 1211 nh = ipv6_hdr(skb); 1212 1213 if (nh->hop_limit <= 1) 1214 return -EHOSTUNREACH; 1215 1216 key->ip.ttl = --nh->hop_limit; 1217 } else if (skb->protocol == htons(ETH_P_IP)) { 1218 struct iphdr *nh; 1219 u8 old_ttl; 1220 1221 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1222 sizeof(*nh)); 1223 if (unlikely(err)) 1224 return err; 1225 1226 nh = ip_hdr(skb); 1227 if (nh->ttl <= 1) 1228 return -EHOSTUNREACH; 1229 1230 old_ttl = nh->ttl--; 1231 csum_replace2(&nh->check, htons(old_ttl << 8), 1232 htons(nh->ttl << 8)); 1233 key->ip.ttl = nh->ttl; 1234 } 1235 return 0; 1236 } 1237 1238 /* Execute a list of actions against 'skb'. */ 1239 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1240 struct sw_flow_key *key, 1241 const struct nlattr *attr, int len) 1242 { 1243 const struct nlattr *a; 1244 int rem; 1245 1246 for (a = attr, rem = len; rem > 0; 1247 a = nla_next(a, &rem)) { 1248 int err = 0; 1249 1250 if (trace_ovs_do_execute_action_enabled()) 1251 trace_ovs_do_execute_action(dp, skb, key, a, rem); 1252 1253 switch (nla_type(a)) { 1254 case OVS_ACTION_ATTR_OUTPUT: { 1255 int port = nla_get_u32(a); 1256 struct sk_buff *clone; 1257 1258 /* Every output action needs a separate clone 1259 * of 'skb', In case the output action is the 1260 * last action, cloning can be avoided. 1261 */ 1262 if (nla_is_last(a, rem)) { 1263 do_output(dp, skb, port, key); 1264 /* 'skb' has been used for output. 1265 */ 1266 return 0; 1267 } 1268 1269 clone = skb_clone(skb, GFP_ATOMIC); 1270 if (clone) 1271 do_output(dp, clone, port, key); 1272 OVS_CB(skb)->cutlen = 0; 1273 break; 1274 } 1275 1276 case OVS_ACTION_ATTR_TRUNC: { 1277 struct ovs_action_trunc *trunc = nla_data(a); 1278 1279 if (skb->len > trunc->max_len) 1280 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1281 break; 1282 } 1283 1284 case OVS_ACTION_ATTR_USERSPACE: 1285 output_userspace(dp, skb, key, a, attr, 1286 len, OVS_CB(skb)->cutlen); 1287 OVS_CB(skb)->cutlen = 0; 1288 break; 1289 1290 case OVS_ACTION_ATTR_HASH: 1291 execute_hash(skb, key, a); 1292 break; 1293 1294 case OVS_ACTION_ATTR_PUSH_MPLS: { 1295 struct ovs_action_push_mpls *mpls = nla_data(a); 1296 1297 err = push_mpls(skb, key, mpls->mpls_lse, 1298 mpls->mpls_ethertype, skb->mac_len); 1299 break; 1300 } 1301 case OVS_ACTION_ATTR_ADD_MPLS: { 1302 struct ovs_action_add_mpls *mpls = nla_data(a); 1303 __u16 mac_len = 0; 1304 1305 if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK) 1306 mac_len = skb->mac_len; 1307 1308 err = push_mpls(skb, key, mpls->mpls_lse, 1309 mpls->mpls_ethertype, mac_len); 1310 break; 1311 } 1312 case OVS_ACTION_ATTR_POP_MPLS: 1313 err = pop_mpls(skb, key, nla_get_be16(a)); 1314 break; 1315 1316 case OVS_ACTION_ATTR_PUSH_VLAN: 1317 err = push_vlan(skb, key, nla_data(a)); 1318 break; 1319 1320 case OVS_ACTION_ATTR_POP_VLAN: 1321 err = pop_vlan(skb, key); 1322 break; 1323 1324 case OVS_ACTION_ATTR_RECIRC: { 1325 bool last = nla_is_last(a, rem); 1326 1327 err = execute_recirc(dp, skb, key, a, last); 1328 if (last) { 1329 /* If this is the last action, the skb has 1330 * been consumed or freed. 1331 * Return immediately. 1332 */ 1333 return err; 1334 } 1335 break; 1336 } 1337 1338 case OVS_ACTION_ATTR_SET: 1339 err = execute_set_action(skb, key, nla_data(a)); 1340 break; 1341 1342 case OVS_ACTION_ATTR_SET_MASKED: 1343 case OVS_ACTION_ATTR_SET_TO_MASKED: 1344 err = execute_masked_set_action(skb, key, nla_data(a)); 1345 break; 1346 1347 case OVS_ACTION_ATTR_SAMPLE: { 1348 bool last = nla_is_last(a, rem); 1349 1350 err = sample(dp, skb, key, a, last); 1351 if (last) 1352 return err; 1353 1354 break; 1355 } 1356 1357 case OVS_ACTION_ATTR_CT: 1358 if (!is_flow_key_valid(key)) { 1359 err = ovs_flow_key_update(skb, key); 1360 if (err) 1361 return err; 1362 } 1363 1364 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1365 nla_data(a)); 1366 1367 /* Hide stolen IP fragments from user space. */ 1368 if (err) 1369 return err == -EINPROGRESS ? 0 : err; 1370 break; 1371 1372 case OVS_ACTION_ATTR_CT_CLEAR: 1373 err = ovs_ct_clear(skb, key); 1374 break; 1375 1376 case OVS_ACTION_ATTR_PUSH_ETH: 1377 err = push_eth(skb, key, nla_data(a)); 1378 break; 1379 1380 case OVS_ACTION_ATTR_POP_ETH: 1381 err = pop_eth(skb, key); 1382 break; 1383 1384 case OVS_ACTION_ATTR_PUSH_NSH: { 1385 u8 buffer[NSH_HDR_MAX_LEN]; 1386 struct nshhdr *nh = (struct nshhdr *)buffer; 1387 1388 err = nsh_hdr_from_nlattr(nla_data(a), nh, 1389 NSH_HDR_MAX_LEN); 1390 if (unlikely(err)) 1391 break; 1392 err = push_nsh(skb, key, nh); 1393 break; 1394 } 1395 1396 case OVS_ACTION_ATTR_POP_NSH: 1397 err = pop_nsh(skb, key); 1398 break; 1399 1400 case OVS_ACTION_ATTR_METER: 1401 if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { 1402 consume_skb(skb); 1403 return 0; 1404 } 1405 break; 1406 1407 case OVS_ACTION_ATTR_CLONE: { 1408 bool last = nla_is_last(a, rem); 1409 1410 err = clone(dp, skb, key, a, last); 1411 if (last) 1412 return err; 1413 1414 break; 1415 } 1416 1417 case OVS_ACTION_ATTR_CHECK_PKT_LEN: { 1418 bool last = nla_is_last(a, rem); 1419 1420 err = execute_check_pkt_len(dp, skb, key, a, last); 1421 if (last) 1422 return err; 1423 1424 break; 1425 } 1426 1427 case OVS_ACTION_ATTR_DEC_TTL: 1428 err = execute_dec_ttl(skb, key); 1429 if (err == -EHOSTUNREACH) 1430 return dec_ttl_exception_handler(dp, skb, 1431 key, a); 1432 break; 1433 } 1434 1435 if (unlikely(err)) { 1436 kfree_skb(skb); 1437 return err; 1438 } 1439 } 1440 1441 consume_skb(skb); 1442 return 0; 1443 } 1444 1445 /* Execute the actions on the clone of the packet. The effect of the 1446 * execution does not affect the original 'skb' nor the original 'key'. 1447 * 1448 * The execution may be deferred in case the actions can not be executed 1449 * immediately. 1450 */ 1451 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 1452 struct sw_flow_key *key, u32 recirc_id, 1453 const struct nlattr *actions, int len, 1454 bool last, bool clone_flow_key) 1455 { 1456 struct deferred_action *da; 1457 struct sw_flow_key *clone; 1458 1459 skb = last ? skb : skb_clone(skb, GFP_ATOMIC); 1460 if (!skb) { 1461 /* Out of memory, skip this action. 1462 */ 1463 return 0; 1464 } 1465 1466 /* When clone_flow_key is false, the 'key' will not be change 1467 * by the actions, then the 'key' can be used directly. 1468 * Otherwise, try to clone key from the next recursion level of 1469 * 'flow_keys'. If clone is successful, execute the actions 1470 * without deferring. 1471 */ 1472 clone = clone_flow_key ? clone_key(key) : key; 1473 if (clone) { 1474 int err = 0; 1475 1476 if (actions) { /* Sample action */ 1477 if (clone_flow_key) 1478 __this_cpu_inc(exec_actions_level); 1479 1480 err = do_execute_actions(dp, skb, clone, 1481 actions, len); 1482 1483 if (clone_flow_key) 1484 __this_cpu_dec(exec_actions_level); 1485 } else { /* Recirc action */ 1486 clone->recirc_id = recirc_id; 1487 ovs_dp_process_packet(skb, clone); 1488 } 1489 return err; 1490 } 1491 1492 /* Out of 'flow_keys' space. Defer actions */ 1493 da = add_deferred_actions(skb, key, actions, len); 1494 if (da) { 1495 if (!actions) { /* Recirc action */ 1496 key = &da->pkt_key; 1497 key->recirc_id = recirc_id; 1498 } 1499 } else { 1500 /* Out of per CPU action FIFO space. Drop the 'skb' and 1501 * log an error. 1502 */ 1503 kfree_skb(skb); 1504 1505 if (net_ratelimit()) { 1506 if (actions) { /* Sample action */ 1507 pr_warn("%s: deferred action limit reached, drop sample action\n", 1508 ovs_dp_name(dp)); 1509 } else { /* Recirc action */ 1510 pr_warn("%s: deferred action limit reached, drop recirc action\n", 1511 ovs_dp_name(dp)); 1512 } 1513 } 1514 } 1515 return 0; 1516 } 1517 1518 static void process_deferred_actions(struct datapath *dp) 1519 { 1520 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1521 1522 /* Do not touch the FIFO in case there is no deferred actions. */ 1523 if (action_fifo_is_empty(fifo)) 1524 return; 1525 1526 /* Finishing executing all deferred actions. */ 1527 do { 1528 struct deferred_action *da = action_fifo_get(fifo); 1529 struct sk_buff *skb = da->skb; 1530 struct sw_flow_key *key = &da->pkt_key; 1531 const struct nlattr *actions = da->actions; 1532 int actions_len = da->actions_len; 1533 1534 if (actions) 1535 do_execute_actions(dp, skb, key, actions, actions_len); 1536 else 1537 ovs_dp_process_packet(skb, key); 1538 } while (!action_fifo_is_empty(fifo)); 1539 1540 /* Reset FIFO for the next packet. */ 1541 action_fifo_init(fifo); 1542 } 1543 1544 /* Execute a list of actions against 'skb'. */ 1545 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1546 const struct sw_flow_actions *acts, 1547 struct sw_flow_key *key) 1548 { 1549 int err, level; 1550 1551 level = __this_cpu_inc_return(exec_actions_level); 1552 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1553 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1554 ovs_dp_name(dp)); 1555 kfree_skb(skb); 1556 err = -ENETDOWN; 1557 goto out; 1558 } 1559 1560 OVS_CB(skb)->acts_origlen = acts->orig_len; 1561 err = do_execute_actions(dp, skb, key, 1562 acts->actions, acts->actions_len); 1563 1564 if (level == 1) 1565 process_deferred_actions(dp); 1566 1567 out: 1568 __this_cpu_dec(exec_actions_level); 1569 return err; 1570 } 1571 1572 int action_fifos_init(void) 1573 { 1574 action_fifos = alloc_percpu(struct action_fifo); 1575 if (!action_fifos) 1576 return -ENOMEM; 1577 1578 flow_keys = alloc_percpu(struct action_flow_keys); 1579 if (!flow_keys) { 1580 free_percpu(action_fifos); 1581 return -ENOMEM; 1582 } 1583 1584 return 0; 1585 } 1586 1587 void action_fifos_exit(void) 1588 { 1589 free_percpu(action_fifos); 1590 free_percpu(flow_keys); 1591 } 1592