1 /* 2 * Copyright (c) 2007-2017 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 20 21 #include <linux/skbuff.h> 22 #include <linux/in.h> 23 #include <linux/ip.h> 24 #include <linux/openvswitch.h> 25 #include <linux/netfilter_ipv6.h> 26 #include <linux/sctp.h> 27 #include <linux/tcp.h> 28 #include <linux/udp.h> 29 #include <linux/in6.h> 30 #include <linux/if_arp.h> 31 #include <linux/if_vlan.h> 32 33 #include <net/dst.h> 34 #include <net/ip.h> 35 #include <net/ipv6.h> 36 #include <net/ip6_fib.h> 37 #include <net/checksum.h> 38 #include <net/dsfield.h> 39 #include <net/mpls.h> 40 #include <net/sctp/checksum.h> 41 42 #include "datapath.h" 43 #include "flow.h" 44 #include "conntrack.h" 45 #include "vport.h" 46 #include "flow_netlink.h" 47 48 struct deferred_action { 49 struct sk_buff *skb; 50 const struct nlattr *actions; 51 int actions_len; 52 53 /* Store pkt_key clone when creating deferred action. */ 54 struct sw_flow_key pkt_key; 55 }; 56 57 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN) 58 struct ovs_frag_data { 59 unsigned long dst; 60 struct vport *vport; 61 struct ovs_skb_cb cb; 62 __be16 inner_protocol; 63 u16 network_offset; /* valid only for MPLS */ 64 u16 vlan_tci; 65 __be16 vlan_proto; 66 unsigned int l2_len; 67 u8 mac_proto; 68 u8 l2_data[MAX_L2_LEN]; 69 }; 70 71 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); 72 73 #define DEFERRED_ACTION_FIFO_SIZE 10 74 #define OVS_RECURSION_LIMIT 5 75 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2) 76 struct action_fifo { 77 int head; 78 int tail; 79 /* Deferred action fifo queue storage. */ 80 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; 81 }; 82 83 struct action_flow_keys { 84 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD]; 85 }; 86 87 static struct action_fifo __percpu *action_fifos; 88 static struct action_flow_keys __percpu *flow_keys; 89 static DEFINE_PER_CPU(int, exec_actions_level); 90 91 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys' 92 * space. Return NULL if out of key spaces. 93 */ 94 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_) 95 { 96 struct action_flow_keys *keys = this_cpu_ptr(flow_keys); 97 int level = this_cpu_read(exec_actions_level); 98 struct sw_flow_key *key = NULL; 99 100 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) { 101 key = &keys->key[level - 1]; 102 *key = *key_; 103 } 104 105 return key; 106 } 107 108 static void action_fifo_init(struct action_fifo *fifo) 109 { 110 fifo->head = 0; 111 fifo->tail = 0; 112 } 113 114 static bool action_fifo_is_empty(const struct action_fifo *fifo) 115 { 116 return (fifo->head == fifo->tail); 117 } 118 119 static struct deferred_action *action_fifo_get(struct action_fifo *fifo) 120 { 121 if (action_fifo_is_empty(fifo)) 122 return NULL; 123 124 return &fifo->fifo[fifo->tail++]; 125 } 126 127 static struct deferred_action *action_fifo_put(struct action_fifo *fifo) 128 { 129 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) 130 return NULL; 131 132 return &fifo->fifo[fifo->head++]; 133 } 134 135 /* Return true if fifo is not full */ 136 static struct deferred_action *add_deferred_actions(struct sk_buff *skb, 137 const struct sw_flow_key *key, 138 const struct nlattr *actions, 139 const int actions_len) 140 { 141 struct action_fifo *fifo; 142 struct deferred_action *da; 143 144 fifo = this_cpu_ptr(action_fifos); 145 da = action_fifo_put(fifo); 146 if (da) { 147 da->skb = skb; 148 da->actions = actions; 149 da->actions_len = actions_len; 150 da->pkt_key = *key; 151 } 152 153 return da; 154 } 155 156 static void invalidate_flow_key(struct sw_flow_key *key) 157 { 158 key->mac_proto |= SW_FLOW_KEY_INVALID; 159 } 160 161 static bool is_flow_key_valid(const struct sw_flow_key *key) 162 { 163 return !(key->mac_proto & SW_FLOW_KEY_INVALID); 164 } 165 166 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 167 struct sw_flow_key *key, 168 u32 recirc_id, 169 const struct nlattr *actions, int len, 170 bool last, bool clone_flow_key); 171 172 static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr, 173 __be16 ethertype) 174 { 175 if (skb->ip_summed == CHECKSUM_COMPLETE) { 176 __be16 diff[] = { ~(hdr->h_proto), ethertype }; 177 178 skb->csum = ~csum_partial((char *)diff, sizeof(diff), 179 ~skb->csum); 180 } 181 182 hdr->h_proto = ethertype; 183 } 184 185 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key, 186 const struct ovs_action_push_mpls *mpls) 187 { 188 struct mpls_shim_hdr *new_mpls_lse; 189 190 /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */ 191 if (skb->encapsulation) 192 return -ENOTSUPP; 193 194 if (skb_cow_head(skb, MPLS_HLEN) < 0) 195 return -ENOMEM; 196 197 if (!skb->inner_protocol) { 198 skb_set_inner_network_header(skb, skb->mac_len); 199 skb_set_inner_protocol(skb, skb->protocol); 200 } 201 202 skb_push(skb, MPLS_HLEN); 203 memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb), 204 skb->mac_len); 205 skb_reset_mac_header(skb); 206 skb_set_network_header(skb, skb->mac_len); 207 208 new_mpls_lse = mpls_hdr(skb); 209 new_mpls_lse->label_stack_entry = mpls->mpls_lse; 210 211 skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN); 212 213 if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET) 214 update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype); 215 skb->protocol = mpls->mpls_ethertype; 216 217 invalidate_flow_key(key); 218 return 0; 219 } 220 221 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key, 222 const __be16 ethertype) 223 { 224 int err; 225 226 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); 227 if (unlikely(err)) 228 return err; 229 230 skb_postpull_rcsum(skb, mpls_hdr(skb), MPLS_HLEN); 231 232 memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb), 233 skb->mac_len); 234 235 __skb_pull(skb, MPLS_HLEN); 236 skb_reset_mac_header(skb); 237 skb_set_network_header(skb, skb->mac_len); 238 239 if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET) { 240 struct ethhdr *hdr; 241 242 /* mpls_hdr() is used to locate the ethertype field correctly in the 243 * presence of VLAN tags. 244 */ 245 hdr = (struct ethhdr *)((void *)mpls_hdr(skb) - ETH_HLEN); 246 update_ethertype(skb, hdr, ethertype); 247 } 248 if (eth_p_mpls(skb->protocol)) 249 skb->protocol = ethertype; 250 251 invalidate_flow_key(key); 252 return 0; 253 } 254 255 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key, 256 const __be32 *mpls_lse, const __be32 *mask) 257 { 258 struct mpls_shim_hdr *stack; 259 __be32 lse; 260 int err; 261 262 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); 263 if (unlikely(err)) 264 return err; 265 266 stack = mpls_hdr(skb); 267 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); 268 if (skb->ip_summed == CHECKSUM_COMPLETE) { 269 __be32 diff[] = { ~(stack->label_stack_entry), lse }; 270 271 skb->csum = ~csum_partial((char *)diff, sizeof(diff), 272 ~skb->csum); 273 } 274 275 stack->label_stack_entry = lse; 276 flow_key->mpls.top_lse = lse; 277 return 0; 278 } 279 280 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key) 281 { 282 int err; 283 284 err = skb_vlan_pop(skb); 285 if (skb_vlan_tag_present(skb)) { 286 invalidate_flow_key(key); 287 } else { 288 key->eth.vlan.tci = 0; 289 key->eth.vlan.tpid = 0; 290 } 291 return err; 292 } 293 294 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key, 295 const struct ovs_action_push_vlan *vlan) 296 { 297 if (skb_vlan_tag_present(skb)) { 298 invalidate_flow_key(key); 299 } else { 300 key->eth.vlan.tci = vlan->vlan_tci; 301 key->eth.vlan.tpid = vlan->vlan_tpid; 302 } 303 return skb_vlan_push(skb, vlan->vlan_tpid, 304 ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT); 305 } 306 307 /* 'src' is already properly masked. */ 308 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) 309 { 310 u16 *dst = (u16 *)dst_; 311 const u16 *src = (const u16 *)src_; 312 const u16 *mask = (const u16 *)mask_; 313 314 OVS_SET_MASKED(dst[0], src[0], mask[0]); 315 OVS_SET_MASKED(dst[1], src[1], mask[1]); 316 OVS_SET_MASKED(dst[2], src[2], mask[2]); 317 } 318 319 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, 320 const struct ovs_key_ethernet *key, 321 const struct ovs_key_ethernet *mask) 322 { 323 int err; 324 325 err = skb_ensure_writable(skb, ETH_HLEN); 326 if (unlikely(err)) 327 return err; 328 329 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 330 331 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 332 mask->eth_src); 333 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 334 mask->eth_dst); 335 336 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 337 338 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 339 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); 340 return 0; 341 } 342 343 /* pop_eth does not support VLAN packets as this action is never called 344 * for them. 345 */ 346 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key) 347 { 348 skb_pull_rcsum(skb, ETH_HLEN); 349 skb_reset_mac_header(skb); 350 skb_reset_mac_len(skb); 351 352 /* safe right before invalidate_flow_key */ 353 key->mac_proto = MAC_PROTO_NONE; 354 invalidate_flow_key(key); 355 return 0; 356 } 357 358 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key, 359 const struct ovs_action_push_eth *ethh) 360 { 361 struct ethhdr *hdr; 362 363 /* Add the new Ethernet header */ 364 if (skb_cow_head(skb, ETH_HLEN) < 0) 365 return -ENOMEM; 366 367 skb_push(skb, ETH_HLEN); 368 skb_reset_mac_header(skb); 369 skb_reset_mac_len(skb); 370 371 hdr = eth_hdr(skb); 372 ether_addr_copy(hdr->h_source, ethh->addresses.eth_src); 373 ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst); 374 hdr->h_proto = skb->protocol; 375 376 skb_postpush_rcsum(skb, hdr, ETH_HLEN); 377 378 /* safe right before invalidate_flow_key */ 379 key->mac_proto = MAC_PROTO_ETHERNET; 380 invalidate_flow_key(key); 381 return 0; 382 } 383 384 static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key, 385 const struct nshhdr *nh) 386 { 387 int err; 388 389 err = nsh_push(skb, nh); 390 if (err) 391 return err; 392 393 /* safe right before invalidate_flow_key */ 394 key->mac_proto = MAC_PROTO_NONE; 395 invalidate_flow_key(key); 396 return 0; 397 } 398 399 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key) 400 { 401 int err; 402 403 err = nsh_pop(skb); 404 if (err) 405 return err; 406 407 /* safe right before invalidate_flow_key */ 408 if (skb->protocol == htons(ETH_P_TEB)) 409 key->mac_proto = MAC_PROTO_ETHERNET; 410 else 411 key->mac_proto = MAC_PROTO_NONE; 412 invalidate_flow_key(key); 413 return 0; 414 } 415 416 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, 417 __be32 addr, __be32 new_addr) 418 { 419 int transport_len = skb->len - skb_transport_offset(skb); 420 421 if (nh->frag_off & htons(IP_OFFSET)) 422 return; 423 424 if (nh->protocol == IPPROTO_TCP) { 425 if (likely(transport_len >= sizeof(struct tcphdr))) 426 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 427 addr, new_addr, true); 428 } else if (nh->protocol == IPPROTO_UDP) { 429 if (likely(transport_len >= sizeof(struct udphdr))) { 430 struct udphdr *uh = udp_hdr(skb); 431 432 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 433 inet_proto_csum_replace4(&uh->check, skb, 434 addr, new_addr, true); 435 if (!uh->check) 436 uh->check = CSUM_MANGLED_0; 437 } 438 } 439 } 440 } 441 442 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 443 __be32 *addr, __be32 new_addr) 444 { 445 update_ip_l4_checksum(skb, nh, *addr, new_addr); 446 csum_replace4(&nh->check, *addr, new_addr); 447 skb_clear_hash(skb); 448 *addr = new_addr; 449 } 450 451 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 452 __be32 addr[4], const __be32 new_addr[4]) 453 { 454 int transport_len = skb->len - skb_transport_offset(skb); 455 456 if (l4_proto == NEXTHDR_TCP) { 457 if (likely(transport_len >= sizeof(struct tcphdr))) 458 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 459 addr, new_addr, true); 460 } else if (l4_proto == NEXTHDR_UDP) { 461 if (likely(transport_len >= sizeof(struct udphdr))) { 462 struct udphdr *uh = udp_hdr(skb); 463 464 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 465 inet_proto_csum_replace16(&uh->check, skb, 466 addr, new_addr, true); 467 if (!uh->check) 468 uh->check = CSUM_MANGLED_0; 469 } 470 } 471 } else if (l4_proto == NEXTHDR_ICMP) { 472 if (likely(transport_len >= sizeof(struct icmp6hdr))) 473 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 474 skb, addr, new_addr, true); 475 } 476 } 477 478 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 479 const __be32 mask[4], __be32 masked[4]) 480 { 481 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 482 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 483 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 484 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 485 } 486 487 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 488 __be32 addr[4], const __be32 new_addr[4], 489 bool recalculate_csum) 490 { 491 if (recalculate_csum) 492 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 493 494 skb_clear_hash(skb); 495 memcpy(addr, new_addr, sizeof(__be32[4])); 496 } 497 498 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask) 499 { 500 /* Bits 21-24 are always unmasked, so this retains their values. */ 501 OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16)); 502 OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8)); 503 OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask); 504 } 505 506 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 507 u8 mask) 508 { 509 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 510 511 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 512 nh->ttl = new_ttl; 513 } 514 515 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 516 const struct ovs_key_ipv4 *key, 517 const struct ovs_key_ipv4 *mask) 518 { 519 struct iphdr *nh; 520 __be32 new_addr; 521 int err; 522 523 err = skb_ensure_writable(skb, skb_network_offset(skb) + 524 sizeof(struct iphdr)); 525 if (unlikely(err)) 526 return err; 527 528 nh = ip_hdr(skb); 529 530 /* Setting an IP addresses is typically only a side effect of 531 * matching on them in the current userspace implementation, so it 532 * makes sense to check if the value actually changed. 533 */ 534 if (mask->ipv4_src) { 535 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 536 537 if (unlikely(new_addr != nh->saddr)) { 538 set_ip_addr(skb, nh, &nh->saddr, new_addr); 539 flow_key->ipv4.addr.src = new_addr; 540 } 541 } 542 if (mask->ipv4_dst) { 543 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 544 545 if (unlikely(new_addr != nh->daddr)) { 546 set_ip_addr(skb, nh, &nh->daddr, new_addr); 547 flow_key->ipv4.addr.dst = new_addr; 548 } 549 } 550 if (mask->ipv4_tos) { 551 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 552 flow_key->ip.tos = nh->tos; 553 } 554 if (mask->ipv4_ttl) { 555 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 556 flow_key->ip.ttl = nh->ttl; 557 } 558 559 return 0; 560 } 561 562 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 563 { 564 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 565 } 566 567 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 568 const struct ovs_key_ipv6 *key, 569 const struct ovs_key_ipv6 *mask) 570 { 571 struct ipv6hdr *nh; 572 int err; 573 574 err = skb_ensure_writable(skb, skb_network_offset(skb) + 575 sizeof(struct ipv6hdr)); 576 if (unlikely(err)) 577 return err; 578 579 nh = ipv6_hdr(skb); 580 581 /* Setting an IP addresses is typically only a side effect of 582 * matching on them in the current userspace implementation, so it 583 * makes sense to check if the value actually changed. 584 */ 585 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 586 __be32 *saddr = (__be32 *)&nh->saddr; 587 __be32 masked[4]; 588 589 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 590 591 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 592 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 593 true); 594 memcpy(&flow_key->ipv6.addr.src, masked, 595 sizeof(flow_key->ipv6.addr.src)); 596 } 597 } 598 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 599 unsigned int offset = 0; 600 int flags = IP6_FH_F_SKIP_RH; 601 bool recalc_csum = true; 602 __be32 *daddr = (__be32 *)&nh->daddr; 603 __be32 masked[4]; 604 605 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 606 607 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 608 if (ipv6_ext_hdr(nh->nexthdr)) 609 recalc_csum = (ipv6_find_hdr(skb, &offset, 610 NEXTHDR_ROUTING, 611 NULL, &flags) 612 != NEXTHDR_ROUTING); 613 614 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 615 recalc_csum); 616 memcpy(&flow_key->ipv6.addr.dst, masked, 617 sizeof(flow_key->ipv6.addr.dst)); 618 } 619 } 620 if (mask->ipv6_tclass) { 621 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass); 622 flow_key->ip.tos = ipv6_get_dsfield(nh); 623 } 624 if (mask->ipv6_label) { 625 set_ipv6_fl(nh, ntohl(key->ipv6_label), 626 ntohl(mask->ipv6_label)); 627 flow_key->ipv6.label = 628 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 629 } 630 if (mask->ipv6_hlimit) { 631 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit, 632 mask->ipv6_hlimit); 633 flow_key->ip.ttl = nh->hop_limit; 634 } 635 return 0; 636 } 637 638 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, 639 const struct nlattr *a) 640 { 641 struct nshhdr *nh; 642 size_t length; 643 int err; 644 u8 flags; 645 u8 ttl; 646 int i; 647 648 struct ovs_key_nsh key; 649 struct ovs_key_nsh mask; 650 651 err = nsh_key_from_nlattr(a, &key, &mask); 652 if (err) 653 return err; 654 655 /* Make sure the NSH base header is there */ 656 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 657 return -ENOMEM; 658 659 nh = nsh_hdr(skb); 660 length = nsh_hdr_len(nh); 661 662 /* Make sure the whole NSH header is there */ 663 err = skb_ensure_writable(skb, skb_network_offset(skb) + 664 length); 665 if (unlikely(err)) 666 return err; 667 668 nh = nsh_hdr(skb); 669 skb_postpull_rcsum(skb, nh, length); 670 flags = nsh_get_flags(nh); 671 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 672 flow_key->nsh.base.flags = flags; 673 ttl = nsh_get_ttl(nh); 674 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); 675 flow_key->nsh.base.ttl = ttl; 676 nsh_set_flags_and_ttl(nh, flags, ttl); 677 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, 678 mask.base.path_hdr); 679 flow_key->nsh.base.path_hdr = nh->path_hdr; 680 switch (nh->mdtype) { 681 case NSH_M_TYPE1: 682 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { 683 nh->md1.context[i] = 684 OVS_MASKED(nh->md1.context[i], key.context[i], 685 mask.context[i]); 686 } 687 memcpy(flow_key->nsh.context, nh->md1.context, 688 sizeof(nh->md1.context)); 689 break; 690 case NSH_M_TYPE2: 691 memset(flow_key->nsh.context, 0, 692 sizeof(flow_key->nsh.context)); 693 break; 694 default: 695 return -EINVAL; 696 } 697 skb_postpush_rcsum(skb, nh, length); 698 return 0; 699 } 700 701 /* Must follow skb_ensure_writable() since that can move the skb data. */ 702 static void set_tp_port(struct sk_buff *skb, __be16 *port, 703 __be16 new_port, __sum16 *check) 704 { 705 inet_proto_csum_replace2(check, skb, *port, new_port, false); 706 *port = new_port; 707 } 708 709 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 710 const struct ovs_key_udp *key, 711 const struct ovs_key_udp *mask) 712 { 713 struct udphdr *uh; 714 __be16 src, dst; 715 int err; 716 717 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 718 sizeof(struct udphdr)); 719 if (unlikely(err)) 720 return err; 721 722 uh = udp_hdr(skb); 723 /* Either of the masks is non-zero, so do not bother checking them. */ 724 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 725 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 726 727 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 728 if (likely(src != uh->source)) { 729 set_tp_port(skb, &uh->source, src, &uh->check); 730 flow_key->tp.src = src; 731 } 732 if (likely(dst != uh->dest)) { 733 set_tp_port(skb, &uh->dest, dst, &uh->check); 734 flow_key->tp.dst = dst; 735 } 736 737 if (unlikely(!uh->check)) 738 uh->check = CSUM_MANGLED_0; 739 } else { 740 uh->source = src; 741 uh->dest = dst; 742 flow_key->tp.src = src; 743 flow_key->tp.dst = dst; 744 } 745 746 skb_clear_hash(skb); 747 748 return 0; 749 } 750 751 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 752 const struct ovs_key_tcp *key, 753 const struct ovs_key_tcp *mask) 754 { 755 struct tcphdr *th; 756 __be16 src, dst; 757 int err; 758 759 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 760 sizeof(struct tcphdr)); 761 if (unlikely(err)) 762 return err; 763 764 th = tcp_hdr(skb); 765 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 766 if (likely(src != th->source)) { 767 set_tp_port(skb, &th->source, src, &th->check); 768 flow_key->tp.src = src; 769 } 770 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 771 if (likely(dst != th->dest)) { 772 set_tp_port(skb, &th->dest, dst, &th->check); 773 flow_key->tp.dst = dst; 774 } 775 skb_clear_hash(skb); 776 777 return 0; 778 } 779 780 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 781 const struct ovs_key_sctp *key, 782 const struct ovs_key_sctp *mask) 783 { 784 unsigned int sctphoff = skb_transport_offset(skb); 785 struct sctphdr *sh; 786 __le32 old_correct_csum, new_csum, old_csum; 787 int err; 788 789 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 790 if (unlikely(err)) 791 return err; 792 793 sh = sctp_hdr(skb); 794 old_csum = sh->checksum; 795 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 796 797 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 798 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 799 800 new_csum = sctp_compute_cksum(skb, sctphoff); 801 802 /* Carry any checksum errors through. */ 803 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 804 805 skb_clear_hash(skb); 806 flow_key->tp.src = sh->source; 807 flow_key->tp.dst = sh->dest; 808 809 return 0; 810 } 811 812 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb) 813 { 814 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 815 struct vport *vport = data->vport; 816 817 if (skb_cow_head(skb, data->l2_len) < 0) { 818 kfree_skb(skb); 819 return -ENOMEM; 820 } 821 822 __skb_dst_copy(skb, data->dst); 823 *OVS_CB(skb) = data->cb; 824 skb->inner_protocol = data->inner_protocol; 825 skb->vlan_tci = data->vlan_tci; 826 skb->vlan_proto = data->vlan_proto; 827 828 /* Reconstruct the MAC header. */ 829 skb_push(skb, data->l2_len); 830 memcpy(skb->data, &data->l2_data, data->l2_len); 831 skb_postpush_rcsum(skb, skb->data, data->l2_len); 832 skb_reset_mac_header(skb); 833 834 if (eth_p_mpls(skb->protocol)) { 835 skb->inner_network_header = skb->network_header; 836 skb_set_network_header(skb, data->network_offset); 837 skb_reset_mac_len(skb); 838 } 839 840 ovs_vport_send(vport, skb, data->mac_proto); 841 return 0; 842 } 843 844 static unsigned int 845 ovs_dst_get_mtu(const struct dst_entry *dst) 846 { 847 return dst->dev->mtu; 848 } 849 850 static struct dst_ops ovs_dst_ops = { 851 .family = AF_UNSPEC, 852 .mtu = ovs_dst_get_mtu, 853 }; 854 855 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 856 * ovs_vport_output(), which is called once per fragmented packet. 857 */ 858 static void prepare_frag(struct vport *vport, struct sk_buff *skb, 859 u16 orig_network_offset, u8 mac_proto) 860 { 861 unsigned int hlen = skb_network_offset(skb); 862 struct ovs_frag_data *data; 863 864 data = this_cpu_ptr(&ovs_frag_data_storage); 865 data->dst = skb->_skb_refdst; 866 data->vport = vport; 867 data->cb = *OVS_CB(skb); 868 data->inner_protocol = skb->inner_protocol; 869 data->network_offset = orig_network_offset; 870 data->vlan_tci = skb->vlan_tci; 871 data->vlan_proto = skb->vlan_proto; 872 data->mac_proto = mac_proto; 873 data->l2_len = hlen; 874 memcpy(&data->l2_data, skb->data, hlen); 875 876 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 877 skb_pull(skb, hlen); 878 } 879 880 static void ovs_fragment(struct net *net, struct vport *vport, 881 struct sk_buff *skb, u16 mru, 882 struct sw_flow_key *key) 883 { 884 u16 orig_network_offset = 0; 885 886 if (eth_p_mpls(skb->protocol)) { 887 orig_network_offset = skb_network_offset(skb); 888 skb->network_header = skb->inner_network_header; 889 } 890 891 if (skb_network_offset(skb) > MAX_L2_LEN) { 892 OVS_NLERR(1, "L2 header too long to fragment"); 893 goto err; 894 } 895 896 if (key->eth.type == htons(ETH_P_IP)) { 897 struct dst_entry ovs_dst; 898 unsigned long orig_dst; 899 900 prepare_frag(vport, skb, orig_network_offset, 901 ovs_key_mac_proto(key)); 902 dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1, 903 DST_OBSOLETE_NONE, DST_NOCOUNT); 904 ovs_dst.dev = vport->dev; 905 906 orig_dst = skb->_skb_refdst; 907 skb_dst_set_noref(skb, &ovs_dst); 908 IPCB(skb)->frag_max_size = mru; 909 910 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 911 refdst_drop(orig_dst); 912 } else if (key->eth.type == htons(ETH_P_IPV6)) { 913 const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops(); 914 unsigned long orig_dst; 915 struct rt6_info ovs_rt; 916 917 if (!v6ops) 918 goto err; 919 920 prepare_frag(vport, skb, orig_network_offset, 921 ovs_key_mac_proto(key)); 922 memset(&ovs_rt, 0, sizeof(ovs_rt)); 923 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, 924 DST_OBSOLETE_NONE, DST_NOCOUNT); 925 ovs_rt.dst.dev = vport->dev; 926 927 orig_dst = skb->_skb_refdst; 928 skb_dst_set_noref(skb, &ovs_rt.dst); 929 IP6CB(skb)->frag_max_size = mru; 930 931 v6ops->fragment(net, skb->sk, skb, ovs_vport_output); 932 refdst_drop(orig_dst); 933 } else { 934 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 935 ovs_vport_name(vport), ntohs(key->eth.type), mru, 936 vport->dev->mtu); 937 goto err; 938 } 939 940 return; 941 err: 942 kfree_skb(skb); 943 } 944 945 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 946 struct sw_flow_key *key) 947 { 948 struct vport *vport = ovs_vport_rcu(dp, out_port); 949 950 if (likely(vport)) { 951 u16 mru = OVS_CB(skb)->mru; 952 u32 cutlen = OVS_CB(skb)->cutlen; 953 954 if (unlikely(cutlen > 0)) { 955 if (skb->len - cutlen > ovs_mac_header_len(key)) 956 pskb_trim(skb, skb->len - cutlen); 957 else 958 pskb_trim(skb, ovs_mac_header_len(key)); 959 } 960 961 if (likely(!mru || 962 (skb->len <= mru + vport->dev->hard_header_len))) { 963 ovs_vport_send(vport, skb, ovs_key_mac_proto(key)); 964 } else if (mru <= vport->dev->mtu) { 965 struct net *net = read_pnet(&dp->net); 966 967 ovs_fragment(net, vport, skb, mru, key); 968 } else { 969 kfree_skb(skb); 970 } 971 } else { 972 kfree_skb(skb); 973 } 974 } 975 976 static int output_userspace(struct datapath *dp, struct sk_buff *skb, 977 struct sw_flow_key *key, const struct nlattr *attr, 978 const struct nlattr *actions, int actions_len, 979 uint32_t cutlen) 980 { 981 struct dp_upcall_info upcall; 982 const struct nlattr *a; 983 int rem; 984 985 memset(&upcall, 0, sizeof(upcall)); 986 upcall.cmd = OVS_PACKET_CMD_ACTION; 987 upcall.mru = OVS_CB(skb)->mru; 988 989 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 990 a = nla_next(a, &rem)) { 991 switch (nla_type(a)) { 992 case OVS_USERSPACE_ATTR_USERDATA: 993 upcall.userdata = a; 994 break; 995 996 case OVS_USERSPACE_ATTR_PID: 997 upcall.portid = nla_get_u32(a); 998 break; 999 1000 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 1001 /* Get out tunnel info. */ 1002 struct vport *vport; 1003 1004 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 1005 if (vport) { 1006 int err; 1007 1008 err = dev_fill_metadata_dst(vport->dev, skb); 1009 if (!err) 1010 upcall.egress_tun_info = skb_tunnel_info(skb); 1011 } 1012 1013 break; 1014 } 1015 1016 case OVS_USERSPACE_ATTR_ACTIONS: { 1017 /* Include actions. */ 1018 upcall.actions = actions; 1019 upcall.actions_len = actions_len; 1020 break; 1021 } 1022 1023 } /* End of switch. */ 1024 } 1025 1026 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 1027 } 1028 1029 /* When 'last' is true, sample() should always consume the 'skb'. 1030 * Otherwise, sample() should keep 'skb' intact regardless what 1031 * actions are executed within sample(). 1032 */ 1033 static int sample(struct datapath *dp, struct sk_buff *skb, 1034 struct sw_flow_key *key, const struct nlattr *attr, 1035 bool last) 1036 { 1037 struct nlattr *actions; 1038 struct nlattr *sample_arg; 1039 int rem = nla_len(attr); 1040 const struct sample_arg *arg; 1041 bool clone_flow_key; 1042 1043 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ 1044 sample_arg = nla_data(attr); 1045 arg = nla_data(sample_arg); 1046 actions = nla_next(sample_arg, &rem); 1047 1048 if ((arg->probability != U32_MAX) && 1049 (!arg->probability || prandom_u32() > arg->probability)) { 1050 if (last) 1051 consume_skb(skb); 1052 return 0; 1053 } 1054 1055 clone_flow_key = !arg->exec; 1056 return clone_execute(dp, skb, key, 0, actions, rem, last, 1057 clone_flow_key); 1058 } 1059 1060 /* When 'last' is true, clone() should always consume the 'skb'. 1061 * Otherwise, clone() should keep 'skb' intact regardless what 1062 * actions are executed within clone(). 1063 */ 1064 static int clone(struct datapath *dp, struct sk_buff *skb, 1065 struct sw_flow_key *key, const struct nlattr *attr, 1066 bool last) 1067 { 1068 struct nlattr *actions; 1069 struct nlattr *clone_arg; 1070 int rem = nla_len(attr); 1071 bool dont_clone_flow_key; 1072 1073 /* The first action is always 'OVS_CLONE_ATTR_ARG'. */ 1074 clone_arg = nla_data(attr); 1075 dont_clone_flow_key = nla_get_u32(clone_arg); 1076 actions = nla_next(clone_arg, &rem); 1077 1078 return clone_execute(dp, skb, key, 0, actions, rem, last, 1079 !dont_clone_flow_key); 1080 } 1081 1082 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 1083 const struct nlattr *attr) 1084 { 1085 struct ovs_action_hash *hash_act = nla_data(attr); 1086 u32 hash = 0; 1087 1088 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */ 1089 hash = skb_get_hash(skb); 1090 hash = jhash_1word(hash, hash_act->hash_basis); 1091 if (!hash) 1092 hash = 0x1; 1093 1094 key->ovs_flow_hash = hash; 1095 } 1096 1097 static int execute_set_action(struct sk_buff *skb, 1098 struct sw_flow_key *flow_key, 1099 const struct nlattr *a) 1100 { 1101 /* Only tunnel set execution is supported without a mask. */ 1102 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1103 struct ovs_tunnel_info *tun = nla_data(a); 1104 1105 skb_dst_drop(skb); 1106 dst_hold((struct dst_entry *)tun->tun_dst); 1107 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 1108 return 0; 1109 } 1110 1111 return -EINVAL; 1112 } 1113 1114 /* Mask is at the midpoint of the data. */ 1115 #define get_mask(a, type) ((const type)nla_data(a) + 1) 1116 1117 static int execute_masked_set_action(struct sk_buff *skb, 1118 struct sw_flow_key *flow_key, 1119 const struct nlattr *a) 1120 { 1121 int err = 0; 1122 1123 switch (nla_type(a)) { 1124 case OVS_KEY_ATTR_PRIORITY: 1125 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 1126 *get_mask(a, u32 *)); 1127 flow_key->phy.priority = skb->priority; 1128 break; 1129 1130 case OVS_KEY_ATTR_SKB_MARK: 1131 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 1132 flow_key->phy.skb_mark = skb->mark; 1133 break; 1134 1135 case OVS_KEY_ATTR_TUNNEL_INFO: 1136 /* Masked data not supported for tunnel. */ 1137 err = -EINVAL; 1138 break; 1139 1140 case OVS_KEY_ATTR_ETHERNET: 1141 err = set_eth_addr(skb, flow_key, nla_data(a), 1142 get_mask(a, struct ovs_key_ethernet *)); 1143 break; 1144 1145 case OVS_KEY_ATTR_NSH: 1146 err = set_nsh(skb, flow_key, a); 1147 break; 1148 1149 case OVS_KEY_ATTR_IPV4: 1150 err = set_ipv4(skb, flow_key, nla_data(a), 1151 get_mask(a, struct ovs_key_ipv4 *)); 1152 break; 1153 1154 case OVS_KEY_ATTR_IPV6: 1155 err = set_ipv6(skb, flow_key, nla_data(a), 1156 get_mask(a, struct ovs_key_ipv6 *)); 1157 break; 1158 1159 case OVS_KEY_ATTR_TCP: 1160 err = set_tcp(skb, flow_key, nla_data(a), 1161 get_mask(a, struct ovs_key_tcp *)); 1162 break; 1163 1164 case OVS_KEY_ATTR_UDP: 1165 err = set_udp(skb, flow_key, nla_data(a), 1166 get_mask(a, struct ovs_key_udp *)); 1167 break; 1168 1169 case OVS_KEY_ATTR_SCTP: 1170 err = set_sctp(skb, flow_key, nla_data(a), 1171 get_mask(a, struct ovs_key_sctp *)); 1172 break; 1173 1174 case OVS_KEY_ATTR_MPLS: 1175 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1176 __be32 *)); 1177 break; 1178 1179 case OVS_KEY_ATTR_CT_STATE: 1180 case OVS_KEY_ATTR_CT_ZONE: 1181 case OVS_KEY_ATTR_CT_MARK: 1182 case OVS_KEY_ATTR_CT_LABELS: 1183 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: 1184 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: 1185 err = -EINVAL; 1186 break; 1187 } 1188 1189 return err; 1190 } 1191 1192 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1193 struct sw_flow_key *key, 1194 const struct nlattr *a, bool last) 1195 { 1196 u32 recirc_id; 1197 1198 if (!is_flow_key_valid(key)) { 1199 int err; 1200 1201 err = ovs_flow_key_update(skb, key); 1202 if (err) 1203 return err; 1204 } 1205 BUG_ON(!is_flow_key_valid(key)); 1206 1207 recirc_id = nla_get_u32(a); 1208 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); 1209 } 1210 1211 /* Execute a list of actions against 'skb'. */ 1212 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1213 struct sw_flow_key *key, 1214 const struct nlattr *attr, int len) 1215 { 1216 const struct nlattr *a; 1217 int rem; 1218 1219 for (a = attr, rem = len; rem > 0; 1220 a = nla_next(a, &rem)) { 1221 int err = 0; 1222 1223 switch (nla_type(a)) { 1224 case OVS_ACTION_ATTR_OUTPUT: { 1225 int port = nla_get_u32(a); 1226 struct sk_buff *clone; 1227 1228 /* Every output action needs a separate clone 1229 * of 'skb', In case the output action is the 1230 * last action, cloning can be avoided. 1231 */ 1232 if (nla_is_last(a, rem)) { 1233 do_output(dp, skb, port, key); 1234 /* 'skb' has been used for output. 1235 */ 1236 return 0; 1237 } 1238 1239 clone = skb_clone(skb, GFP_ATOMIC); 1240 if (clone) 1241 do_output(dp, clone, port, key); 1242 OVS_CB(skb)->cutlen = 0; 1243 break; 1244 } 1245 1246 case OVS_ACTION_ATTR_TRUNC: { 1247 struct ovs_action_trunc *trunc = nla_data(a); 1248 1249 if (skb->len > trunc->max_len) 1250 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1251 break; 1252 } 1253 1254 case OVS_ACTION_ATTR_USERSPACE: 1255 output_userspace(dp, skb, key, a, attr, 1256 len, OVS_CB(skb)->cutlen); 1257 OVS_CB(skb)->cutlen = 0; 1258 break; 1259 1260 case OVS_ACTION_ATTR_HASH: 1261 execute_hash(skb, key, a); 1262 break; 1263 1264 case OVS_ACTION_ATTR_PUSH_MPLS: 1265 err = push_mpls(skb, key, nla_data(a)); 1266 break; 1267 1268 case OVS_ACTION_ATTR_POP_MPLS: 1269 err = pop_mpls(skb, key, nla_get_be16(a)); 1270 break; 1271 1272 case OVS_ACTION_ATTR_PUSH_VLAN: 1273 err = push_vlan(skb, key, nla_data(a)); 1274 break; 1275 1276 case OVS_ACTION_ATTR_POP_VLAN: 1277 err = pop_vlan(skb, key); 1278 break; 1279 1280 case OVS_ACTION_ATTR_RECIRC: { 1281 bool last = nla_is_last(a, rem); 1282 1283 err = execute_recirc(dp, skb, key, a, last); 1284 if (last) { 1285 /* If this is the last action, the skb has 1286 * been consumed or freed. 1287 * Return immediately. 1288 */ 1289 return err; 1290 } 1291 break; 1292 } 1293 1294 case OVS_ACTION_ATTR_SET: 1295 err = execute_set_action(skb, key, nla_data(a)); 1296 break; 1297 1298 case OVS_ACTION_ATTR_SET_MASKED: 1299 case OVS_ACTION_ATTR_SET_TO_MASKED: 1300 err = execute_masked_set_action(skb, key, nla_data(a)); 1301 break; 1302 1303 case OVS_ACTION_ATTR_SAMPLE: { 1304 bool last = nla_is_last(a, rem); 1305 1306 err = sample(dp, skb, key, a, last); 1307 if (last) 1308 return err; 1309 1310 break; 1311 } 1312 1313 case OVS_ACTION_ATTR_CT: 1314 if (!is_flow_key_valid(key)) { 1315 err = ovs_flow_key_update(skb, key); 1316 if (err) 1317 return err; 1318 } 1319 1320 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1321 nla_data(a)); 1322 1323 /* Hide stolen IP fragments from user space. */ 1324 if (err) 1325 return err == -EINPROGRESS ? 0 : err; 1326 break; 1327 1328 case OVS_ACTION_ATTR_CT_CLEAR: 1329 err = ovs_ct_clear(skb, key); 1330 break; 1331 1332 case OVS_ACTION_ATTR_PUSH_ETH: 1333 err = push_eth(skb, key, nla_data(a)); 1334 break; 1335 1336 case OVS_ACTION_ATTR_POP_ETH: 1337 err = pop_eth(skb, key); 1338 break; 1339 1340 case OVS_ACTION_ATTR_PUSH_NSH: { 1341 u8 buffer[NSH_HDR_MAX_LEN]; 1342 struct nshhdr *nh = (struct nshhdr *)buffer; 1343 1344 err = nsh_hdr_from_nlattr(nla_data(a), nh, 1345 NSH_HDR_MAX_LEN); 1346 if (unlikely(err)) 1347 break; 1348 err = push_nsh(skb, key, nh); 1349 break; 1350 } 1351 1352 case OVS_ACTION_ATTR_POP_NSH: 1353 err = pop_nsh(skb, key); 1354 break; 1355 1356 case OVS_ACTION_ATTR_METER: 1357 if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { 1358 consume_skb(skb); 1359 return 0; 1360 } 1361 break; 1362 1363 case OVS_ACTION_ATTR_CLONE: { 1364 bool last = nla_is_last(a, rem); 1365 1366 err = clone(dp, skb, key, a, last); 1367 if (last) 1368 return err; 1369 1370 break; 1371 } 1372 } 1373 1374 if (unlikely(err)) { 1375 kfree_skb(skb); 1376 return err; 1377 } 1378 } 1379 1380 consume_skb(skb); 1381 return 0; 1382 } 1383 1384 /* Execute the actions on the clone of the packet. The effect of the 1385 * execution does not affect the original 'skb' nor the original 'key'. 1386 * 1387 * The execution may be deferred in case the actions can not be executed 1388 * immediately. 1389 */ 1390 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 1391 struct sw_flow_key *key, u32 recirc_id, 1392 const struct nlattr *actions, int len, 1393 bool last, bool clone_flow_key) 1394 { 1395 struct deferred_action *da; 1396 struct sw_flow_key *clone; 1397 1398 skb = last ? skb : skb_clone(skb, GFP_ATOMIC); 1399 if (!skb) { 1400 /* Out of memory, skip this action. 1401 */ 1402 return 0; 1403 } 1404 1405 /* When clone_flow_key is false, the 'key' will not be change 1406 * by the actions, then the 'key' can be used directly. 1407 * Otherwise, try to clone key from the next recursion level of 1408 * 'flow_keys'. If clone is successful, execute the actions 1409 * without deferring. 1410 */ 1411 clone = clone_flow_key ? clone_key(key) : key; 1412 if (clone) { 1413 int err = 0; 1414 1415 if (actions) { /* Sample action */ 1416 if (clone_flow_key) 1417 __this_cpu_inc(exec_actions_level); 1418 1419 err = do_execute_actions(dp, skb, clone, 1420 actions, len); 1421 1422 if (clone_flow_key) 1423 __this_cpu_dec(exec_actions_level); 1424 } else { /* Recirc action */ 1425 clone->recirc_id = recirc_id; 1426 ovs_dp_process_packet(skb, clone); 1427 } 1428 return err; 1429 } 1430 1431 /* Out of 'flow_keys' space. Defer actions */ 1432 da = add_deferred_actions(skb, key, actions, len); 1433 if (da) { 1434 if (!actions) { /* Recirc action */ 1435 key = &da->pkt_key; 1436 key->recirc_id = recirc_id; 1437 } 1438 } else { 1439 /* Out of per CPU action FIFO space. Drop the 'skb' and 1440 * log an error. 1441 */ 1442 kfree_skb(skb); 1443 1444 if (net_ratelimit()) { 1445 if (actions) { /* Sample action */ 1446 pr_warn("%s: deferred action limit reached, drop sample action\n", 1447 ovs_dp_name(dp)); 1448 } else { /* Recirc action */ 1449 pr_warn("%s: deferred action limit reached, drop recirc action\n", 1450 ovs_dp_name(dp)); 1451 } 1452 } 1453 } 1454 return 0; 1455 } 1456 1457 static void process_deferred_actions(struct datapath *dp) 1458 { 1459 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1460 1461 /* Do not touch the FIFO in case there is no deferred actions. */ 1462 if (action_fifo_is_empty(fifo)) 1463 return; 1464 1465 /* Finishing executing all deferred actions. */ 1466 do { 1467 struct deferred_action *da = action_fifo_get(fifo); 1468 struct sk_buff *skb = da->skb; 1469 struct sw_flow_key *key = &da->pkt_key; 1470 const struct nlattr *actions = da->actions; 1471 int actions_len = da->actions_len; 1472 1473 if (actions) 1474 do_execute_actions(dp, skb, key, actions, actions_len); 1475 else 1476 ovs_dp_process_packet(skb, key); 1477 } while (!action_fifo_is_empty(fifo)); 1478 1479 /* Reset FIFO for the next packet. */ 1480 action_fifo_init(fifo); 1481 } 1482 1483 /* Execute a list of actions against 'skb'. */ 1484 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1485 const struct sw_flow_actions *acts, 1486 struct sw_flow_key *key) 1487 { 1488 int err, level; 1489 1490 level = __this_cpu_inc_return(exec_actions_level); 1491 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1492 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1493 ovs_dp_name(dp)); 1494 kfree_skb(skb); 1495 err = -ENETDOWN; 1496 goto out; 1497 } 1498 1499 OVS_CB(skb)->acts_origlen = acts->orig_len; 1500 err = do_execute_actions(dp, skb, key, 1501 acts->actions, acts->actions_len); 1502 1503 if (level == 1) 1504 process_deferred_actions(dp); 1505 1506 out: 1507 __this_cpu_dec(exec_actions_level); 1508 return err; 1509 } 1510 1511 int action_fifos_init(void) 1512 { 1513 action_fifos = alloc_percpu(struct action_fifo); 1514 if (!action_fifos) 1515 return -ENOMEM; 1516 1517 flow_keys = alloc_percpu(struct action_flow_keys); 1518 if (!flow_keys) { 1519 free_percpu(action_fifos); 1520 return -ENOMEM; 1521 } 1522 1523 return 0; 1524 } 1525 1526 void action_fifos_exit(void) 1527 { 1528 free_percpu(action_fifos); 1529 free_percpu(flow_keys); 1530 } 1531