1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2007-2017 Nicira, Inc. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/skbuff.h> 9 #include <linux/in.h> 10 #include <linux/ip.h> 11 #include <linux/openvswitch.h> 12 #include <linux/sctp.h> 13 #include <linux/tcp.h> 14 #include <linux/udp.h> 15 #include <linux/in6.h> 16 #include <linux/if_arp.h> 17 #include <linux/if_vlan.h> 18 19 #include <net/dst.h> 20 #include <net/gso.h> 21 #include <net/ip.h> 22 #include <net/ipv6.h> 23 #include <net/ip6_fib.h> 24 #include <net/checksum.h> 25 #include <net/dsfield.h> 26 #include <net/mpls.h> 27 #include <net/sctp/checksum.h> 28 29 #include "datapath.h" 30 #include "drop.h" 31 #include "flow.h" 32 #include "conntrack.h" 33 #include "vport.h" 34 #include "flow_netlink.h" 35 #include "openvswitch_trace.h" 36 37 struct deferred_action { 38 struct sk_buff *skb; 39 const struct nlattr *actions; 40 int actions_len; 41 42 /* Store pkt_key clone when creating deferred action. */ 43 struct sw_flow_key pkt_key; 44 }; 45 46 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN) 47 struct ovs_frag_data { 48 unsigned long dst; 49 struct vport *vport; 50 struct ovs_skb_cb cb; 51 __be16 inner_protocol; 52 u16 network_offset; /* valid only for MPLS */ 53 u16 vlan_tci; 54 __be16 vlan_proto; 55 unsigned int l2_len; 56 u8 mac_proto; 57 u8 l2_data[MAX_L2_LEN]; 58 }; 59 60 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); 61 62 #define DEFERRED_ACTION_FIFO_SIZE 10 63 #define OVS_RECURSION_LIMIT 5 64 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2) 65 struct action_fifo { 66 int head; 67 int tail; 68 /* Deferred action fifo queue storage. */ 69 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; 70 }; 71 72 struct action_flow_keys { 73 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD]; 74 }; 75 76 static struct action_fifo __percpu *action_fifos; 77 static struct action_flow_keys __percpu *flow_keys; 78 static DEFINE_PER_CPU(int, exec_actions_level); 79 80 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys' 81 * space. Return NULL if out of key spaces. 82 */ 83 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_) 84 { 85 struct action_flow_keys *keys = this_cpu_ptr(flow_keys); 86 int level = this_cpu_read(exec_actions_level); 87 struct sw_flow_key *key = NULL; 88 89 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) { 90 key = &keys->key[level - 1]; 91 *key = *key_; 92 } 93 94 return key; 95 } 96 97 static void action_fifo_init(struct action_fifo *fifo) 98 { 99 fifo->head = 0; 100 fifo->tail = 0; 101 } 102 103 static bool action_fifo_is_empty(const struct action_fifo *fifo) 104 { 105 return (fifo->head == fifo->tail); 106 } 107 108 static struct deferred_action *action_fifo_get(struct action_fifo *fifo) 109 { 110 if (action_fifo_is_empty(fifo)) 111 return NULL; 112 113 return &fifo->fifo[fifo->tail++]; 114 } 115 116 static struct deferred_action *action_fifo_put(struct action_fifo *fifo) 117 { 118 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) 119 return NULL; 120 121 return &fifo->fifo[fifo->head++]; 122 } 123 124 /* Return true if fifo is not full */ 125 static struct deferred_action *add_deferred_actions(struct sk_buff *skb, 126 const struct sw_flow_key *key, 127 const struct nlattr *actions, 128 const int actions_len) 129 { 130 struct action_fifo *fifo; 131 struct deferred_action *da; 132 133 fifo = this_cpu_ptr(action_fifos); 134 da = action_fifo_put(fifo); 135 if (da) { 136 da->skb = skb; 137 da->actions = actions; 138 da->actions_len = actions_len; 139 da->pkt_key = *key; 140 } 141 142 return da; 143 } 144 145 static void invalidate_flow_key(struct sw_flow_key *key) 146 { 147 key->mac_proto |= SW_FLOW_KEY_INVALID; 148 } 149 150 static bool is_flow_key_valid(const struct sw_flow_key *key) 151 { 152 return !(key->mac_proto & SW_FLOW_KEY_INVALID); 153 } 154 155 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 156 struct sw_flow_key *key, 157 u32 recirc_id, 158 const struct nlattr *actions, int len, 159 bool last, bool clone_flow_key); 160 161 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 162 struct sw_flow_key *key, 163 const struct nlattr *attr, int len); 164 165 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key, 166 __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len) 167 { 168 int err; 169 170 err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len); 171 if (err) 172 return err; 173 174 if (!mac_len) 175 key->mac_proto = MAC_PROTO_NONE; 176 177 invalidate_flow_key(key); 178 return 0; 179 } 180 181 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key, 182 const __be16 ethertype) 183 { 184 int err; 185 186 err = skb_mpls_pop(skb, ethertype, skb->mac_len, 187 ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET); 188 if (err) 189 return err; 190 191 if (ethertype == htons(ETH_P_TEB)) 192 key->mac_proto = MAC_PROTO_ETHERNET; 193 194 invalidate_flow_key(key); 195 return 0; 196 } 197 198 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key, 199 const __be32 *mpls_lse, const __be32 *mask) 200 { 201 struct mpls_shim_hdr *stack; 202 __be32 lse; 203 int err; 204 205 if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN)) 206 return -ENOMEM; 207 208 stack = mpls_hdr(skb); 209 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); 210 err = skb_mpls_update_lse(skb, lse); 211 if (err) 212 return err; 213 214 flow_key->mpls.lse[0] = lse; 215 return 0; 216 } 217 218 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key) 219 { 220 int err; 221 222 err = skb_vlan_pop(skb); 223 if (skb_vlan_tag_present(skb)) { 224 invalidate_flow_key(key); 225 } else { 226 key->eth.vlan.tci = 0; 227 key->eth.vlan.tpid = 0; 228 } 229 return err; 230 } 231 232 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key, 233 const struct ovs_action_push_vlan *vlan) 234 { 235 if (skb_vlan_tag_present(skb)) { 236 invalidate_flow_key(key); 237 } else { 238 key->eth.vlan.tci = vlan->vlan_tci; 239 key->eth.vlan.tpid = vlan->vlan_tpid; 240 } 241 return skb_vlan_push(skb, vlan->vlan_tpid, 242 ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK); 243 } 244 245 /* 'src' is already properly masked. */ 246 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) 247 { 248 u16 *dst = (u16 *)dst_; 249 const u16 *src = (const u16 *)src_; 250 const u16 *mask = (const u16 *)mask_; 251 252 OVS_SET_MASKED(dst[0], src[0], mask[0]); 253 OVS_SET_MASKED(dst[1], src[1], mask[1]); 254 OVS_SET_MASKED(dst[2], src[2], mask[2]); 255 } 256 257 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, 258 const struct ovs_key_ethernet *key, 259 const struct ovs_key_ethernet *mask) 260 { 261 int err; 262 263 err = skb_ensure_writable(skb, ETH_HLEN); 264 if (unlikely(err)) 265 return err; 266 267 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 268 269 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 270 mask->eth_src); 271 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 272 mask->eth_dst); 273 274 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 275 276 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 277 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); 278 return 0; 279 } 280 281 /* pop_eth does not support VLAN packets as this action is never called 282 * for them. 283 */ 284 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key) 285 { 286 int err; 287 288 err = skb_eth_pop(skb); 289 if (err) 290 return err; 291 292 /* safe right before invalidate_flow_key */ 293 key->mac_proto = MAC_PROTO_NONE; 294 invalidate_flow_key(key); 295 return 0; 296 } 297 298 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key, 299 const struct ovs_action_push_eth *ethh) 300 { 301 int err; 302 303 err = skb_eth_push(skb, ethh->addresses.eth_dst, 304 ethh->addresses.eth_src); 305 if (err) 306 return err; 307 308 /* safe right before invalidate_flow_key */ 309 key->mac_proto = MAC_PROTO_ETHERNET; 310 invalidate_flow_key(key); 311 return 0; 312 } 313 314 static noinline_for_stack int push_nsh(struct sk_buff *skb, 315 struct sw_flow_key *key, 316 const struct nlattr *a) 317 { 318 u8 buffer[NSH_HDR_MAX_LEN]; 319 struct nshhdr *nh = (struct nshhdr *)buffer; 320 int err; 321 322 err = nsh_hdr_from_nlattr(a, nh, NSH_HDR_MAX_LEN); 323 if (err) 324 return err; 325 326 err = nsh_push(skb, nh); 327 if (err) 328 return err; 329 330 /* safe right before invalidate_flow_key */ 331 key->mac_proto = MAC_PROTO_NONE; 332 invalidate_flow_key(key); 333 return 0; 334 } 335 336 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key) 337 { 338 int err; 339 340 err = nsh_pop(skb); 341 if (err) 342 return err; 343 344 /* safe right before invalidate_flow_key */ 345 if (skb->protocol == htons(ETH_P_TEB)) 346 key->mac_proto = MAC_PROTO_ETHERNET; 347 else 348 key->mac_proto = MAC_PROTO_NONE; 349 invalidate_flow_key(key); 350 return 0; 351 } 352 353 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, 354 __be32 addr, __be32 new_addr) 355 { 356 int transport_len = skb->len - skb_transport_offset(skb); 357 358 if (nh->frag_off & htons(IP_OFFSET)) 359 return; 360 361 if (nh->protocol == IPPROTO_TCP) { 362 if (likely(transport_len >= sizeof(struct tcphdr))) 363 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 364 addr, new_addr, true); 365 } else if (nh->protocol == IPPROTO_UDP) { 366 if (likely(transport_len >= sizeof(struct udphdr))) { 367 struct udphdr *uh = udp_hdr(skb); 368 369 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 370 inet_proto_csum_replace4(&uh->check, skb, 371 addr, new_addr, true); 372 if (!uh->check) 373 uh->check = CSUM_MANGLED_0; 374 } 375 } 376 } 377 } 378 379 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 380 __be32 *addr, __be32 new_addr) 381 { 382 update_ip_l4_checksum(skb, nh, *addr, new_addr); 383 csum_replace4(&nh->check, *addr, new_addr); 384 skb_clear_hash(skb); 385 ovs_ct_clear(skb, NULL); 386 *addr = new_addr; 387 } 388 389 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 390 __be32 addr[4], const __be32 new_addr[4]) 391 { 392 int transport_len = skb->len - skb_transport_offset(skb); 393 394 if (l4_proto == NEXTHDR_TCP) { 395 if (likely(transport_len >= sizeof(struct tcphdr))) 396 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 397 addr, new_addr, true); 398 } else if (l4_proto == NEXTHDR_UDP) { 399 if (likely(transport_len >= sizeof(struct udphdr))) { 400 struct udphdr *uh = udp_hdr(skb); 401 402 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 403 inet_proto_csum_replace16(&uh->check, skb, 404 addr, new_addr, true); 405 if (!uh->check) 406 uh->check = CSUM_MANGLED_0; 407 } 408 } 409 } else if (l4_proto == NEXTHDR_ICMP) { 410 if (likely(transport_len >= sizeof(struct icmp6hdr))) 411 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 412 skb, addr, new_addr, true); 413 } 414 } 415 416 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 417 const __be32 mask[4], __be32 masked[4]) 418 { 419 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 420 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 421 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 422 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 423 } 424 425 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 426 __be32 addr[4], const __be32 new_addr[4], 427 bool recalculate_csum) 428 { 429 if (recalculate_csum) 430 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 431 432 skb_clear_hash(skb); 433 ovs_ct_clear(skb, NULL); 434 memcpy(addr, new_addr, sizeof(__be32[4])); 435 } 436 437 static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask) 438 { 439 u8 old_ipv6_tclass = ipv6_get_dsfield(nh); 440 441 ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask); 442 443 if (skb->ip_summed == CHECKSUM_COMPLETE) 444 csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12), 445 (__force __wsum)(ipv6_tclass << 12)); 446 447 ipv6_change_dsfield(nh, ~mask, ipv6_tclass); 448 } 449 450 static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask) 451 { 452 u32 ofl; 453 454 ofl = nh->flow_lbl[0] << 16 | nh->flow_lbl[1] << 8 | nh->flow_lbl[2]; 455 fl = OVS_MASKED(ofl, fl, mask); 456 457 /* Bits 21-24 are always unmasked, so this retains their values. */ 458 nh->flow_lbl[0] = (u8)(fl >> 16); 459 nh->flow_lbl[1] = (u8)(fl >> 8); 460 nh->flow_lbl[2] = (u8)fl; 461 462 if (skb->ip_summed == CHECKSUM_COMPLETE) 463 csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl)); 464 } 465 466 static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask) 467 { 468 new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask); 469 470 if (skb->ip_summed == CHECKSUM_COMPLETE) 471 csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8), 472 (__force __wsum)(new_ttl << 8)); 473 nh->hop_limit = new_ttl; 474 } 475 476 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 477 u8 mask) 478 { 479 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 480 481 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 482 nh->ttl = new_ttl; 483 } 484 485 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 486 const struct ovs_key_ipv4 *key, 487 const struct ovs_key_ipv4 *mask) 488 { 489 struct iphdr *nh; 490 __be32 new_addr; 491 int err; 492 493 err = skb_ensure_writable(skb, skb_network_offset(skb) + 494 sizeof(struct iphdr)); 495 if (unlikely(err)) 496 return err; 497 498 nh = ip_hdr(skb); 499 500 /* Setting an IP addresses is typically only a side effect of 501 * matching on them in the current userspace implementation, so it 502 * makes sense to check if the value actually changed. 503 */ 504 if (mask->ipv4_src) { 505 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 506 507 if (unlikely(new_addr != nh->saddr)) { 508 set_ip_addr(skb, nh, &nh->saddr, new_addr); 509 flow_key->ipv4.addr.src = new_addr; 510 } 511 } 512 if (mask->ipv4_dst) { 513 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 514 515 if (unlikely(new_addr != nh->daddr)) { 516 set_ip_addr(skb, nh, &nh->daddr, new_addr); 517 flow_key->ipv4.addr.dst = new_addr; 518 } 519 } 520 if (mask->ipv4_tos) { 521 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 522 flow_key->ip.tos = nh->tos; 523 } 524 if (mask->ipv4_ttl) { 525 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 526 flow_key->ip.ttl = nh->ttl; 527 } 528 529 return 0; 530 } 531 532 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 533 { 534 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 535 } 536 537 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 538 const struct ovs_key_ipv6 *key, 539 const struct ovs_key_ipv6 *mask) 540 { 541 struct ipv6hdr *nh; 542 int err; 543 544 err = skb_ensure_writable(skb, skb_network_offset(skb) + 545 sizeof(struct ipv6hdr)); 546 if (unlikely(err)) 547 return err; 548 549 nh = ipv6_hdr(skb); 550 551 /* Setting an IP addresses is typically only a side effect of 552 * matching on them in the current userspace implementation, so it 553 * makes sense to check if the value actually changed. 554 */ 555 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 556 __be32 *saddr = (__be32 *)&nh->saddr; 557 __be32 masked[4]; 558 559 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 560 561 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 562 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 563 true); 564 memcpy(&flow_key->ipv6.addr.src, masked, 565 sizeof(flow_key->ipv6.addr.src)); 566 } 567 } 568 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 569 unsigned int offset = 0; 570 int flags = IP6_FH_F_SKIP_RH; 571 bool recalc_csum = true; 572 __be32 *daddr = (__be32 *)&nh->daddr; 573 __be32 masked[4]; 574 575 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 576 577 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 578 if (ipv6_ext_hdr(nh->nexthdr)) 579 recalc_csum = (ipv6_find_hdr(skb, &offset, 580 NEXTHDR_ROUTING, 581 NULL, &flags) 582 != NEXTHDR_ROUTING); 583 584 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 585 recalc_csum); 586 memcpy(&flow_key->ipv6.addr.dst, masked, 587 sizeof(flow_key->ipv6.addr.dst)); 588 } 589 } 590 if (mask->ipv6_tclass) { 591 set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass); 592 flow_key->ip.tos = ipv6_get_dsfield(nh); 593 } 594 if (mask->ipv6_label) { 595 set_ipv6_fl(skb, nh, ntohl(key->ipv6_label), 596 ntohl(mask->ipv6_label)); 597 flow_key->ipv6.label = 598 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 599 } 600 if (mask->ipv6_hlimit) { 601 set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit); 602 flow_key->ip.ttl = nh->hop_limit; 603 } 604 return 0; 605 } 606 607 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, 608 const struct nlattr *a) 609 { 610 struct nshhdr *nh; 611 size_t length; 612 int err; 613 u8 flags; 614 u8 ttl; 615 int i; 616 617 struct ovs_key_nsh key; 618 struct ovs_key_nsh mask; 619 620 err = nsh_key_from_nlattr(a, &key, &mask); 621 if (err) 622 return err; 623 624 /* Make sure the NSH base header is there */ 625 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 626 return -ENOMEM; 627 628 nh = nsh_hdr(skb); 629 length = nsh_hdr_len(nh); 630 631 /* Make sure the whole NSH header is there */ 632 err = skb_ensure_writable(skb, skb_network_offset(skb) + 633 length); 634 if (unlikely(err)) 635 return err; 636 637 nh = nsh_hdr(skb); 638 skb_postpull_rcsum(skb, nh, length); 639 flags = nsh_get_flags(nh); 640 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 641 flow_key->nsh.base.flags = flags; 642 ttl = nsh_get_ttl(nh); 643 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); 644 flow_key->nsh.base.ttl = ttl; 645 nsh_set_flags_and_ttl(nh, flags, ttl); 646 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, 647 mask.base.path_hdr); 648 flow_key->nsh.base.path_hdr = nh->path_hdr; 649 switch (nh->mdtype) { 650 case NSH_M_TYPE1: 651 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { 652 nh->md1.context[i] = 653 OVS_MASKED(nh->md1.context[i], key.context[i], 654 mask.context[i]); 655 } 656 memcpy(flow_key->nsh.context, nh->md1.context, 657 sizeof(nh->md1.context)); 658 break; 659 case NSH_M_TYPE2: 660 memset(flow_key->nsh.context, 0, 661 sizeof(flow_key->nsh.context)); 662 break; 663 default: 664 return -EINVAL; 665 } 666 skb_postpush_rcsum(skb, nh, length); 667 return 0; 668 } 669 670 /* Must follow skb_ensure_writable() since that can move the skb data. */ 671 static void set_tp_port(struct sk_buff *skb, __be16 *port, 672 __be16 new_port, __sum16 *check) 673 { 674 ovs_ct_clear(skb, NULL); 675 inet_proto_csum_replace2(check, skb, *port, new_port, false); 676 *port = new_port; 677 } 678 679 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 680 const struct ovs_key_udp *key, 681 const struct ovs_key_udp *mask) 682 { 683 struct udphdr *uh; 684 __be16 src, dst; 685 int err; 686 687 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 688 sizeof(struct udphdr)); 689 if (unlikely(err)) 690 return err; 691 692 uh = udp_hdr(skb); 693 /* Either of the masks is non-zero, so do not bother checking them. */ 694 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 695 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 696 697 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 698 if (likely(src != uh->source)) { 699 set_tp_port(skb, &uh->source, src, &uh->check); 700 flow_key->tp.src = src; 701 } 702 if (likely(dst != uh->dest)) { 703 set_tp_port(skb, &uh->dest, dst, &uh->check); 704 flow_key->tp.dst = dst; 705 } 706 707 if (unlikely(!uh->check)) 708 uh->check = CSUM_MANGLED_0; 709 } else { 710 uh->source = src; 711 uh->dest = dst; 712 flow_key->tp.src = src; 713 flow_key->tp.dst = dst; 714 ovs_ct_clear(skb, NULL); 715 } 716 717 skb_clear_hash(skb); 718 719 return 0; 720 } 721 722 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 723 const struct ovs_key_tcp *key, 724 const struct ovs_key_tcp *mask) 725 { 726 struct tcphdr *th; 727 __be16 src, dst; 728 int err; 729 730 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 731 sizeof(struct tcphdr)); 732 if (unlikely(err)) 733 return err; 734 735 th = tcp_hdr(skb); 736 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 737 if (likely(src != th->source)) { 738 set_tp_port(skb, &th->source, src, &th->check); 739 flow_key->tp.src = src; 740 } 741 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 742 if (likely(dst != th->dest)) { 743 set_tp_port(skb, &th->dest, dst, &th->check); 744 flow_key->tp.dst = dst; 745 } 746 skb_clear_hash(skb); 747 748 return 0; 749 } 750 751 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 752 const struct ovs_key_sctp *key, 753 const struct ovs_key_sctp *mask) 754 { 755 unsigned int sctphoff = skb_transport_offset(skb); 756 struct sctphdr *sh; 757 __le32 old_correct_csum, new_csum, old_csum; 758 int err; 759 760 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 761 if (unlikely(err)) 762 return err; 763 764 sh = sctp_hdr(skb); 765 old_csum = sh->checksum; 766 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 767 768 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 769 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 770 771 new_csum = sctp_compute_cksum(skb, sctphoff); 772 773 /* Carry any checksum errors through. */ 774 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 775 776 skb_clear_hash(skb); 777 ovs_ct_clear(skb, NULL); 778 779 flow_key->tp.src = sh->source; 780 flow_key->tp.dst = sh->dest; 781 782 return 0; 783 } 784 785 static int ovs_vport_output(struct net *net, struct sock *sk, 786 struct sk_buff *skb) 787 { 788 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 789 struct vport *vport = data->vport; 790 791 if (skb_cow_head(skb, data->l2_len) < 0) { 792 kfree_skb_reason(skb, SKB_DROP_REASON_NOMEM); 793 return -ENOMEM; 794 } 795 796 __skb_dst_copy(skb, data->dst); 797 *OVS_CB(skb) = data->cb; 798 skb->inner_protocol = data->inner_protocol; 799 if (data->vlan_tci & VLAN_CFI_MASK) 800 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); 801 else 802 __vlan_hwaccel_clear_tag(skb); 803 804 /* Reconstruct the MAC header. */ 805 skb_push(skb, data->l2_len); 806 memcpy(skb->data, &data->l2_data, data->l2_len); 807 skb_postpush_rcsum(skb, skb->data, data->l2_len); 808 skb_reset_mac_header(skb); 809 810 if (eth_p_mpls(skb->protocol)) { 811 skb->inner_network_header = skb->network_header; 812 skb_set_network_header(skb, data->network_offset); 813 skb_reset_mac_len(skb); 814 } 815 816 ovs_vport_send(vport, skb, data->mac_proto); 817 return 0; 818 } 819 820 static unsigned int 821 ovs_dst_get_mtu(const struct dst_entry *dst) 822 { 823 return dst->dev->mtu; 824 } 825 826 static struct dst_ops ovs_dst_ops = { 827 .family = AF_UNSPEC, 828 .mtu = ovs_dst_get_mtu, 829 }; 830 831 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 832 * ovs_vport_output(), which is called once per fragmented packet. 833 */ 834 static void prepare_frag(struct vport *vport, struct sk_buff *skb, 835 u16 orig_network_offset, u8 mac_proto) 836 { 837 unsigned int hlen = skb_network_offset(skb); 838 struct ovs_frag_data *data; 839 840 data = this_cpu_ptr(&ovs_frag_data_storage); 841 data->dst = skb->_skb_refdst; 842 data->vport = vport; 843 data->cb = *OVS_CB(skb); 844 data->inner_protocol = skb->inner_protocol; 845 data->network_offset = orig_network_offset; 846 if (skb_vlan_tag_present(skb)) 847 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK; 848 else 849 data->vlan_tci = 0; 850 data->vlan_proto = skb->vlan_proto; 851 data->mac_proto = mac_proto; 852 data->l2_len = hlen; 853 memcpy(&data->l2_data, skb->data, hlen); 854 855 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 856 skb_pull(skb, hlen); 857 } 858 859 static void ovs_fragment(struct net *net, struct vport *vport, 860 struct sk_buff *skb, u16 mru, 861 struct sw_flow_key *key) 862 { 863 enum ovs_drop_reason reason; 864 u16 orig_network_offset = 0; 865 866 if (eth_p_mpls(skb->protocol)) { 867 orig_network_offset = skb_network_offset(skb); 868 skb->network_header = skb->inner_network_header; 869 } 870 871 if (skb_network_offset(skb) > MAX_L2_LEN) { 872 OVS_NLERR(1, "L2 header too long to fragment"); 873 reason = OVS_DROP_FRAG_L2_TOO_LONG; 874 goto err; 875 } 876 877 if (key->eth.type == htons(ETH_P_IP)) { 878 struct rtable ovs_rt = { 0 }; 879 unsigned long orig_dst; 880 881 prepare_frag(vport, skb, orig_network_offset, 882 ovs_key_mac_proto(key)); 883 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 884 DST_OBSOLETE_NONE, DST_NOCOUNT); 885 ovs_rt.dst.dev = vport->dev; 886 887 orig_dst = skb->_skb_refdst; 888 skb_dst_set_noref(skb, &ovs_rt.dst); 889 IPCB(skb)->frag_max_size = mru; 890 891 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 892 refdst_drop(orig_dst); 893 } else if (key->eth.type == htons(ETH_P_IPV6)) { 894 unsigned long orig_dst; 895 struct rt6_info ovs_rt; 896 897 prepare_frag(vport, skb, orig_network_offset, 898 ovs_key_mac_proto(key)); 899 memset(&ovs_rt, 0, sizeof(ovs_rt)); 900 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 901 DST_OBSOLETE_NONE, DST_NOCOUNT); 902 ovs_rt.dst.dev = vport->dev; 903 904 orig_dst = skb->_skb_refdst; 905 skb_dst_set_noref(skb, &ovs_rt.dst); 906 IP6CB(skb)->frag_max_size = mru; 907 908 ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output); 909 refdst_drop(orig_dst); 910 } else { 911 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 912 ovs_vport_name(vport), ntohs(key->eth.type), mru, 913 vport->dev->mtu); 914 reason = OVS_DROP_FRAG_INVALID_PROTO; 915 goto err; 916 } 917 918 return; 919 err: 920 ovs_kfree_skb_reason(skb, reason); 921 } 922 923 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 924 struct sw_flow_key *key) 925 { 926 struct vport *vport = ovs_vport_rcu(dp, out_port); 927 928 if (likely(vport && netif_carrier_ok(vport->dev))) { 929 u16 mru = OVS_CB(skb)->mru; 930 u32 cutlen = OVS_CB(skb)->cutlen; 931 932 if (unlikely(cutlen > 0)) { 933 if (skb->len - cutlen > ovs_mac_header_len(key)) 934 pskb_trim(skb, skb->len - cutlen); 935 else 936 pskb_trim(skb, ovs_mac_header_len(key)); 937 } 938 939 /* Need to set the pkt_type to involve the routing layer. The 940 * packet movement through the OVS datapath doesn't generally 941 * use routing, but this is needed for tunnel cases. 942 */ 943 skb->pkt_type = PACKET_OUTGOING; 944 945 if (likely(!mru || 946 (skb->len <= mru + vport->dev->hard_header_len))) { 947 ovs_vport_send(vport, skb, ovs_key_mac_proto(key)); 948 } else if (mru <= vport->dev->mtu) { 949 struct net *net = read_pnet(&dp->net); 950 951 ovs_fragment(net, vport, skb, mru, key); 952 } else { 953 kfree_skb_reason(skb, SKB_DROP_REASON_PKT_TOO_BIG); 954 } 955 } else { 956 kfree_skb_reason(skb, SKB_DROP_REASON_DEV_READY); 957 } 958 } 959 960 static int output_userspace(struct datapath *dp, struct sk_buff *skb, 961 struct sw_flow_key *key, const struct nlattr *attr, 962 const struct nlattr *actions, int actions_len, 963 uint32_t cutlen) 964 { 965 struct dp_upcall_info upcall; 966 const struct nlattr *a; 967 int rem; 968 969 memset(&upcall, 0, sizeof(upcall)); 970 upcall.cmd = OVS_PACKET_CMD_ACTION; 971 upcall.mru = OVS_CB(skb)->mru; 972 973 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 974 a = nla_next(a, &rem)) { 975 switch (nla_type(a)) { 976 case OVS_USERSPACE_ATTR_USERDATA: 977 upcall.userdata = a; 978 break; 979 980 case OVS_USERSPACE_ATTR_PID: 981 if (dp->user_features & 982 OVS_DP_F_DISPATCH_UPCALL_PER_CPU) 983 upcall.portid = 984 ovs_dp_get_upcall_portid(dp, 985 smp_processor_id()); 986 else 987 upcall.portid = nla_get_u32(a); 988 break; 989 990 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 991 /* Get out tunnel info. */ 992 struct vport *vport; 993 994 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 995 if (vport) { 996 int err; 997 998 err = dev_fill_metadata_dst(vport->dev, skb); 999 if (!err) 1000 upcall.egress_tun_info = skb_tunnel_info(skb); 1001 } 1002 1003 break; 1004 } 1005 1006 case OVS_USERSPACE_ATTR_ACTIONS: { 1007 /* Include actions. */ 1008 upcall.actions = actions; 1009 upcall.actions_len = actions_len; 1010 break; 1011 } 1012 1013 } /* End of switch. */ 1014 } 1015 1016 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 1017 } 1018 1019 static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb, 1020 struct sw_flow_key *key, 1021 const struct nlattr *attr) 1022 { 1023 /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */ 1024 struct nlattr *actions = nla_data(attr); 1025 1026 if (nla_len(actions)) 1027 return clone_execute(dp, skb, key, 0, nla_data(actions), 1028 nla_len(actions), true, false); 1029 1030 ovs_kfree_skb_reason(skb, OVS_DROP_IP_TTL); 1031 return 0; 1032 } 1033 1034 /* When 'last' is true, sample() should always consume the 'skb'. 1035 * Otherwise, sample() should keep 'skb' intact regardless what 1036 * actions are executed within sample(). 1037 */ 1038 static int sample(struct datapath *dp, struct sk_buff *skb, 1039 struct sw_flow_key *key, const struct nlattr *attr, 1040 bool last) 1041 { 1042 struct nlattr *actions; 1043 struct nlattr *sample_arg; 1044 int rem = nla_len(attr); 1045 const struct sample_arg *arg; 1046 bool clone_flow_key; 1047 1048 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ 1049 sample_arg = nla_data(attr); 1050 arg = nla_data(sample_arg); 1051 actions = nla_next(sample_arg, &rem); 1052 1053 if ((arg->probability != U32_MAX) && 1054 (!arg->probability || get_random_u32() > arg->probability)) { 1055 if (last) 1056 ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); 1057 return 0; 1058 } 1059 1060 clone_flow_key = !arg->exec; 1061 return clone_execute(dp, skb, key, 0, actions, rem, last, 1062 clone_flow_key); 1063 } 1064 1065 /* When 'last' is true, clone() should always consume the 'skb'. 1066 * Otherwise, clone() should keep 'skb' intact regardless what 1067 * actions are executed within clone(). 1068 */ 1069 static int clone(struct datapath *dp, struct sk_buff *skb, 1070 struct sw_flow_key *key, const struct nlattr *attr, 1071 bool last) 1072 { 1073 struct nlattr *actions; 1074 struct nlattr *clone_arg; 1075 int rem = nla_len(attr); 1076 bool dont_clone_flow_key; 1077 1078 /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */ 1079 clone_arg = nla_data(attr); 1080 dont_clone_flow_key = nla_get_u32(clone_arg); 1081 actions = nla_next(clone_arg, &rem); 1082 1083 return clone_execute(dp, skb, key, 0, actions, rem, last, 1084 !dont_clone_flow_key); 1085 } 1086 1087 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 1088 const struct nlattr *attr) 1089 { 1090 struct ovs_action_hash *hash_act = nla_data(attr); 1091 u32 hash = 0; 1092 1093 if (hash_act->hash_alg == OVS_HASH_ALG_L4) { 1094 /* OVS_HASH_ALG_L4 hasing type. */ 1095 hash = skb_get_hash(skb); 1096 } else if (hash_act->hash_alg == OVS_HASH_ALG_SYM_L4) { 1097 /* OVS_HASH_ALG_SYM_L4 hashing type. NOTE: this doesn't 1098 * extend past an encapsulated header. 1099 */ 1100 hash = __skb_get_hash_symmetric(skb); 1101 } 1102 1103 hash = jhash_1word(hash, hash_act->hash_basis); 1104 if (!hash) 1105 hash = 0x1; 1106 1107 key->ovs_flow_hash = hash; 1108 } 1109 1110 static int execute_set_action(struct sk_buff *skb, 1111 struct sw_flow_key *flow_key, 1112 const struct nlattr *a) 1113 { 1114 /* Only tunnel set execution is supported without a mask. */ 1115 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1116 struct ovs_tunnel_info *tun = nla_data(a); 1117 1118 skb_dst_drop(skb); 1119 dst_hold((struct dst_entry *)tun->tun_dst); 1120 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 1121 return 0; 1122 } 1123 1124 return -EINVAL; 1125 } 1126 1127 /* Mask is at the midpoint of the data. */ 1128 #define get_mask(a, type) ((const type)nla_data(a) + 1) 1129 1130 static int execute_masked_set_action(struct sk_buff *skb, 1131 struct sw_flow_key *flow_key, 1132 const struct nlattr *a) 1133 { 1134 int err = 0; 1135 1136 switch (nla_type(a)) { 1137 case OVS_KEY_ATTR_PRIORITY: 1138 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 1139 *get_mask(a, u32 *)); 1140 flow_key->phy.priority = skb->priority; 1141 break; 1142 1143 case OVS_KEY_ATTR_SKB_MARK: 1144 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 1145 flow_key->phy.skb_mark = skb->mark; 1146 break; 1147 1148 case OVS_KEY_ATTR_TUNNEL_INFO: 1149 /* Masked data not supported for tunnel. */ 1150 err = -EINVAL; 1151 break; 1152 1153 case OVS_KEY_ATTR_ETHERNET: 1154 err = set_eth_addr(skb, flow_key, nla_data(a), 1155 get_mask(a, struct ovs_key_ethernet *)); 1156 break; 1157 1158 case OVS_KEY_ATTR_NSH: 1159 err = set_nsh(skb, flow_key, a); 1160 break; 1161 1162 case OVS_KEY_ATTR_IPV4: 1163 err = set_ipv4(skb, flow_key, nla_data(a), 1164 get_mask(a, struct ovs_key_ipv4 *)); 1165 break; 1166 1167 case OVS_KEY_ATTR_IPV6: 1168 err = set_ipv6(skb, flow_key, nla_data(a), 1169 get_mask(a, struct ovs_key_ipv6 *)); 1170 break; 1171 1172 case OVS_KEY_ATTR_TCP: 1173 err = set_tcp(skb, flow_key, nla_data(a), 1174 get_mask(a, struct ovs_key_tcp *)); 1175 break; 1176 1177 case OVS_KEY_ATTR_UDP: 1178 err = set_udp(skb, flow_key, nla_data(a), 1179 get_mask(a, struct ovs_key_udp *)); 1180 break; 1181 1182 case OVS_KEY_ATTR_SCTP: 1183 err = set_sctp(skb, flow_key, nla_data(a), 1184 get_mask(a, struct ovs_key_sctp *)); 1185 break; 1186 1187 case OVS_KEY_ATTR_MPLS: 1188 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1189 __be32 *)); 1190 break; 1191 1192 case OVS_KEY_ATTR_CT_STATE: 1193 case OVS_KEY_ATTR_CT_ZONE: 1194 case OVS_KEY_ATTR_CT_MARK: 1195 case OVS_KEY_ATTR_CT_LABELS: 1196 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: 1197 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: 1198 err = -EINVAL; 1199 break; 1200 } 1201 1202 return err; 1203 } 1204 1205 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1206 struct sw_flow_key *key, 1207 const struct nlattr *a, bool last) 1208 { 1209 u32 recirc_id; 1210 1211 if (!is_flow_key_valid(key)) { 1212 int err; 1213 1214 err = ovs_flow_key_update(skb, key); 1215 if (err) 1216 return err; 1217 } 1218 BUG_ON(!is_flow_key_valid(key)); 1219 1220 recirc_id = nla_get_u32(a); 1221 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); 1222 } 1223 1224 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb, 1225 struct sw_flow_key *key, 1226 const struct nlattr *attr, bool last) 1227 { 1228 struct ovs_skb_cb *ovs_cb = OVS_CB(skb); 1229 const struct nlattr *actions, *cpl_arg; 1230 int len, max_len, rem = nla_len(attr); 1231 const struct check_pkt_len_arg *arg; 1232 bool clone_flow_key; 1233 1234 /* The first netlink attribute in 'attr' is always 1235 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'. 1236 */ 1237 cpl_arg = nla_data(attr); 1238 arg = nla_data(cpl_arg); 1239 1240 len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len; 1241 max_len = arg->pkt_len; 1242 1243 if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) || 1244 len <= max_len) { 1245 /* Second netlink attribute in 'attr' is always 1246 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'. 1247 */ 1248 actions = nla_next(cpl_arg, &rem); 1249 clone_flow_key = !arg->exec_for_lesser_equal; 1250 } else { 1251 /* Third netlink attribute in 'attr' is always 1252 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'. 1253 */ 1254 actions = nla_next(cpl_arg, &rem); 1255 actions = nla_next(actions, &rem); 1256 clone_flow_key = !arg->exec_for_greater; 1257 } 1258 1259 return clone_execute(dp, skb, key, 0, nla_data(actions), 1260 nla_len(actions), last, clone_flow_key); 1261 } 1262 1263 static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) 1264 { 1265 int err; 1266 1267 if (skb->protocol == htons(ETH_P_IPV6)) { 1268 struct ipv6hdr *nh; 1269 1270 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1271 sizeof(*nh)); 1272 if (unlikely(err)) 1273 return err; 1274 1275 nh = ipv6_hdr(skb); 1276 1277 if (nh->hop_limit <= 1) 1278 return -EHOSTUNREACH; 1279 1280 key->ip.ttl = --nh->hop_limit; 1281 } else if (skb->protocol == htons(ETH_P_IP)) { 1282 struct iphdr *nh; 1283 u8 old_ttl; 1284 1285 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1286 sizeof(*nh)); 1287 if (unlikely(err)) 1288 return err; 1289 1290 nh = ip_hdr(skb); 1291 if (nh->ttl <= 1) 1292 return -EHOSTUNREACH; 1293 1294 old_ttl = nh->ttl--; 1295 csum_replace2(&nh->check, htons(old_ttl << 8), 1296 htons(nh->ttl << 8)); 1297 key->ip.ttl = nh->ttl; 1298 } 1299 return 0; 1300 } 1301 1302 /* Execute a list of actions against 'skb'. */ 1303 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1304 struct sw_flow_key *key, 1305 const struct nlattr *attr, int len) 1306 { 1307 const struct nlattr *a; 1308 int rem; 1309 1310 for (a = attr, rem = len; rem > 0; 1311 a = nla_next(a, &rem)) { 1312 int err = 0; 1313 1314 if (trace_ovs_do_execute_action_enabled()) 1315 trace_ovs_do_execute_action(dp, skb, key, a, rem); 1316 1317 /* Actions that rightfully have to consume the skb should do it 1318 * and return directly. 1319 */ 1320 switch (nla_type(a)) { 1321 case OVS_ACTION_ATTR_OUTPUT: { 1322 int port = nla_get_u32(a); 1323 struct sk_buff *clone; 1324 1325 /* Every output action needs a separate clone 1326 * of 'skb', In case the output action is the 1327 * last action, cloning can be avoided. 1328 */ 1329 if (nla_is_last(a, rem)) { 1330 do_output(dp, skb, port, key); 1331 /* 'skb' has been used for output. 1332 */ 1333 return 0; 1334 } 1335 1336 clone = skb_clone(skb, GFP_ATOMIC); 1337 if (clone) 1338 do_output(dp, clone, port, key); 1339 OVS_CB(skb)->cutlen = 0; 1340 break; 1341 } 1342 1343 case OVS_ACTION_ATTR_TRUNC: { 1344 struct ovs_action_trunc *trunc = nla_data(a); 1345 1346 if (skb->len > trunc->max_len) 1347 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1348 break; 1349 } 1350 1351 case OVS_ACTION_ATTR_USERSPACE: 1352 output_userspace(dp, skb, key, a, attr, 1353 len, OVS_CB(skb)->cutlen); 1354 OVS_CB(skb)->cutlen = 0; 1355 if (nla_is_last(a, rem)) { 1356 consume_skb(skb); 1357 return 0; 1358 } 1359 break; 1360 1361 case OVS_ACTION_ATTR_HASH: 1362 execute_hash(skb, key, a); 1363 break; 1364 1365 case OVS_ACTION_ATTR_PUSH_MPLS: { 1366 struct ovs_action_push_mpls *mpls = nla_data(a); 1367 1368 err = push_mpls(skb, key, mpls->mpls_lse, 1369 mpls->mpls_ethertype, skb->mac_len); 1370 break; 1371 } 1372 case OVS_ACTION_ATTR_ADD_MPLS: { 1373 struct ovs_action_add_mpls *mpls = nla_data(a); 1374 __u16 mac_len = 0; 1375 1376 if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK) 1377 mac_len = skb->mac_len; 1378 1379 err = push_mpls(skb, key, mpls->mpls_lse, 1380 mpls->mpls_ethertype, mac_len); 1381 break; 1382 } 1383 case OVS_ACTION_ATTR_POP_MPLS: 1384 err = pop_mpls(skb, key, nla_get_be16(a)); 1385 break; 1386 1387 case OVS_ACTION_ATTR_PUSH_VLAN: 1388 err = push_vlan(skb, key, nla_data(a)); 1389 break; 1390 1391 case OVS_ACTION_ATTR_POP_VLAN: 1392 err = pop_vlan(skb, key); 1393 break; 1394 1395 case OVS_ACTION_ATTR_RECIRC: { 1396 bool last = nla_is_last(a, rem); 1397 1398 err = execute_recirc(dp, skb, key, a, last); 1399 if (last) { 1400 /* If this is the last action, the skb has 1401 * been consumed or freed. 1402 * Return immediately. 1403 */ 1404 return err; 1405 } 1406 break; 1407 } 1408 1409 case OVS_ACTION_ATTR_SET: 1410 err = execute_set_action(skb, key, nla_data(a)); 1411 break; 1412 1413 case OVS_ACTION_ATTR_SET_MASKED: 1414 case OVS_ACTION_ATTR_SET_TO_MASKED: 1415 err = execute_masked_set_action(skb, key, nla_data(a)); 1416 break; 1417 1418 case OVS_ACTION_ATTR_SAMPLE: { 1419 bool last = nla_is_last(a, rem); 1420 1421 err = sample(dp, skb, key, a, last); 1422 if (last) 1423 return err; 1424 1425 break; 1426 } 1427 1428 case OVS_ACTION_ATTR_CT: 1429 if (!is_flow_key_valid(key)) { 1430 err = ovs_flow_key_update(skb, key); 1431 if (err) 1432 return err; 1433 } 1434 1435 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1436 nla_data(a)); 1437 1438 /* Hide stolen IP fragments from user space. */ 1439 if (err) 1440 return err == -EINPROGRESS ? 0 : err; 1441 break; 1442 1443 case OVS_ACTION_ATTR_CT_CLEAR: 1444 err = ovs_ct_clear(skb, key); 1445 break; 1446 1447 case OVS_ACTION_ATTR_PUSH_ETH: 1448 err = push_eth(skb, key, nla_data(a)); 1449 break; 1450 1451 case OVS_ACTION_ATTR_POP_ETH: 1452 err = pop_eth(skb, key); 1453 break; 1454 1455 case OVS_ACTION_ATTR_PUSH_NSH: 1456 err = push_nsh(skb, key, nla_data(a)); 1457 break; 1458 1459 case OVS_ACTION_ATTR_POP_NSH: 1460 err = pop_nsh(skb, key); 1461 break; 1462 1463 case OVS_ACTION_ATTR_METER: 1464 if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { 1465 ovs_kfree_skb_reason(skb, OVS_DROP_METER); 1466 return 0; 1467 } 1468 break; 1469 1470 case OVS_ACTION_ATTR_CLONE: { 1471 bool last = nla_is_last(a, rem); 1472 1473 err = clone(dp, skb, key, a, last); 1474 if (last) 1475 return err; 1476 1477 break; 1478 } 1479 1480 case OVS_ACTION_ATTR_CHECK_PKT_LEN: { 1481 bool last = nla_is_last(a, rem); 1482 1483 err = execute_check_pkt_len(dp, skb, key, a, last); 1484 if (last) 1485 return err; 1486 1487 break; 1488 } 1489 1490 case OVS_ACTION_ATTR_DEC_TTL: 1491 err = execute_dec_ttl(skb, key); 1492 if (err == -EHOSTUNREACH) 1493 return dec_ttl_exception_handler(dp, skb, 1494 key, a); 1495 break; 1496 1497 case OVS_ACTION_ATTR_DROP: { 1498 enum ovs_drop_reason reason = nla_get_u32(a) 1499 ? OVS_DROP_EXPLICIT_WITH_ERROR 1500 : OVS_DROP_EXPLICIT; 1501 1502 ovs_kfree_skb_reason(skb, reason); 1503 return 0; 1504 } 1505 } 1506 1507 if (unlikely(err)) { 1508 ovs_kfree_skb_reason(skb, OVS_DROP_ACTION_ERROR); 1509 return err; 1510 } 1511 } 1512 1513 ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); 1514 return 0; 1515 } 1516 1517 /* Execute the actions on the clone of the packet. The effect of the 1518 * execution does not affect the original 'skb' nor the original 'key'. 1519 * 1520 * The execution may be deferred in case the actions can not be executed 1521 * immediately. 1522 */ 1523 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 1524 struct sw_flow_key *key, u32 recirc_id, 1525 const struct nlattr *actions, int len, 1526 bool last, bool clone_flow_key) 1527 { 1528 struct deferred_action *da; 1529 struct sw_flow_key *clone; 1530 1531 skb = last ? skb : skb_clone(skb, GFP_ATOMIC); 1532 if (!skb) { 1533 /* Out of memory, skip this action. 1534 */ 1535 return 0; 1536 } 1537 1538 /* When clone_flow_key is false, the 'key' will not be change 1539 * by the actions, then the 'key' can be used directly. 1540 * Otherwise, try to clone key from the next recursion level of 1541 * 'flow_keys'. If clone is successful, execute the actions 1542 * without deferring. 1543 */ 1544 clone = clone_flow_key ? clone_key(key) : key; 1545 if (clone) { 1546 int err = 0; 1547 1548 if (actions) { /* Sample action */ 1549 if (clone_flow_key) 1550 __this_cpu_inc(exec_actions_level); 1551 1552 err = do_execute_actions(dp, skb, clone, 1553 actions, len); 1554 1555 if (clone_flow_key) 1556 __this_cpu_dec(exec_actions_level); 1557 } else { /* Recirc action */ 1558 clone->recirc_id = recirc_id; 1559 ovs_dp_process_packet(skb, clone); 1560 } 1561 return err; 1562 } 1563 1564 /* Out of 'flow_keys' space. Defer actions */ 1565 da = add_deferred_actions(skb, key, actions, len); 1566 if (da) { 1567 if (!actions) { /* Recirc action */ 1568 key = &da->pkt_key; 1569 key->recirc_id = recirc_id; 1570 } 1571 } else { 1572 /* Out of per CPU action FIFO space. Drop the 'skb' and 1573 * log an error. 1574 */ 1575 ovs_kfree_skb_reason(skb, OVS_DROP_DEFERRED_LIMIT); 1576 1577 if (net_ratelimit()) { 1578 if (actions) { /* Sample action */ 1579 pr_warn("%s: deferred action limit reached, drop sample action\n", 1580 ovs_dp_name(dp)); 1581 } else { /* Recirc action */ 1582 pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n", 1583 ovs_dp_name(dp), recirc_id); 1584 } 1585 } 1586 } 1587 return 0; 1588 } 1589 1590 static void process_deferred_actions(struct datapath *dp) 1591 { 1592 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1593 1594 /* Do not touch the FIFO in case there is no deferred actions. */ 1595 if (action_fifo_is_empty(fifo)) 1596 return; 1597 1598 /* Finishing executing all deferred actions. */ 1599 do { 1600 struct deferred_action *da = action_fifo_get(fifo); 1601 struct sk_buff *skb = da->skb; 1602 struct sw_flow_key *key = &da->pkt_key; 1603 const struct nlattr *actions = da->actions; 1604 int actions_len = da->actions_len; 1605 1606 if (actions) 1607 do_execute_actions(dp, skb, key, actions, actions_len); 1608 else 1609 ovs_dp_process_packet(skb, key); 1610 } while (!action_fifo_is_empty(fifo)); 1611 1612 /* Reset FIFO for the next packet. */ 1613 action_fifo_init(fifo); 1614 } 1615 1616 /* Execute a list of actions against 'skb'. */ 1617 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1618 const struct sw_flow_actions *acts, 1619 struct sw_flow_key *key) 1620 { 1621 int err, level; 1622 1623 level = __this_cpu_inc_return(exec_actions_level); 1624 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1625 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1626 ovs_dp_name(dp)); 1627 ovs_kfree_skb_reason(skb, OVS_DROP_RECURSION_LIMIT); 1628 err = -ENETDOWN; 1629 goto out; 1630 } 1631 1632 OVS_CB(skb)->acts_origlen = acts->orig_len; 1633 err = do_execute_actions(dp, skb, key, 1634 acts->actions, acts->actions_len); 1635 1636 if (level == 1) 1637 process_deferred_actions(dp); 1638 1639 out: 1640 __this_cpu_dec(exec_actions_level); 1641 return err; 1642 } 1643 1644 int action_fifos_init(void) 1645 { 1646 action_fifos = alloc_percpu(struct action_fifo); 1647 if (!action_fifos) 1648 return -ENOMEM; 1649 1650 flow_keys = alloc_percpu(struct action_flow_keys); 1651 if (!flow_keys) { 1652 free_percpu(action_fifos); 1653 return -ENOMEM; 1654 } 1655 1656 return 0; 1657 } 1658 1659 void action_fifos_exit(void) 1660 { 1661 free_percpu(action_fifos); 1662 free_percpu(flow_keys); 1663 } 1664