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