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 28 #if IS_ENABLED(CONFIG_PSAMPLE) 29 #include <net/psample.h> 30 #endif 31 32 #include <net/sctp/checksum.h> 33 34 #include "datapath.h" 35 #include "drop.h" 36 #include "flow.h" 37 #include "conntrack.h" 38 #include "vport.h" 39 #include "flow_netlink.h" 40 #include "openvswitch_trace.h" 41 42 struct deferred_action { 43 struct sk_buff *skb; 44 const struct nlattr *actions; 45 int actions_len; 46 47 /* Store pkt_key clone when creating deferred action. */ 48 struct sw_flow_key pkt_key; 49 }; 50 51 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN) 52 struct ovs_frag_data { 53 unsigned long dst; 54 struct vport *vport; 55 struct ovs_skb_cb cb; 56 __be16 inner_protocol; 57 u16 network_offset; /* valid only for MPLS */ 58 u16 vlan_tci; 59 __be16 vlan_proto; 60 unsigned int l2_len; 61 u8 mac_proto; 62 u8 l2_data[MAX_L2_LEN]; 63 }; 64 65 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); 66 67 #define DEFERRED_ACTION_FIFO_SIZE 10 68 #define OVS_RECURSION_LIMIT 5 69 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2) 70 struct action_fifo { 71 int head; 72 int tail; 73 /* Deferred action fifo queue storage. */ 74 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; 75 }; 76 77 struct action_flow_keys { 78 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD]; 79 }; 80 81 static struct action_fifo __percpu *action_fifos; 82 static struct action_flow_keys __percpu *flow_keys; 83 static DEFINE_PER_CPU(int, exec_actions_level); 84 85 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys' 86 * space. Return NULL if out of key spaces. 87 */ 88 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_) 89 { 90 struct action_flow_keys *keys = this_cpu_ptr(flow_keys); 91 int level = this_cpu_read(exec_actions_level); 92 struct sw_flow_key *key = NULL; 93 94 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) { 95 key = &keys->key[level - 1]; 96 *key = *key_; 97 } 98 99 return key; 100 } 101 102 static void action_fifo_init(struct action_fifo *fifo) 103 { 104 fifo->head = 0; 105 fifo->tail = 0; 106 } 107 108 static bool action_fifo_is_empty(const struct action_fifo *fifo) 109 { 110 return (fifo->head == fifo->tail); 111 } 112 113 static struct deferred_action *action_fifo_get(struct action_fifo *fifo) 114 { 115 if (action_fifo_is_empty(fifo)) 116 return NULL; 117 118 return &fifo->fifo[fifo->tail++]; 119 } 120 121 static struct deferred_action *action_fifo_put(struct action_fifo *fifo) 122 { 123 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) 124 return NULL; 125 126 return &fifo->fifo[fifo->head++]; 127 } 128 129 /* Return true if fifo is not full */ 130 static struct deferred_action *add_deferred_actions(struct sk_buff *skb, 131 const struct sw_flow_key *key, 132 const struct nlattr *actions, 133 const int actions_len) 134 { 135 struct action_fifo *fifo; 136 struct deferred_action *da; 137 138 fifo = this_cpu_ptr(action_fifos); 139 da = action_fifo_put(fifo); 140 if (da) { 141 da->skb = skb; 142 da->actions = actions; 143 da->actions_len = actions_len; 144 da->pkt_key = *key; 145 } 146 147 return da; 148 } 149 150 static void invalidate_flow_key(struct sw_flow_key *key) 151 { 152 key->mac_proto |= SW_FLOW_KEY_INVALID; 153 } 154 155 static bool is_flow_key_valid(const struct sw_flow_key *key) 156 { 157 return !(key->mac_proto & SW_FLOW_KEY_INVALID); 158 } 159 160 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 161 struct sw_flow_key *key, 162 u32 recirc_id, 163 const struct nlattr *actions, int len, 164 bool last, bool clone_flow_key); 165 166 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 167 struct sw_flow_key *key, 168 const struct nlattr *attr, int len); 169 170 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key, 171 __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len) 172 { 173 int err; 174 175 err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len); 176 if (err) 177 return err; 178 179 if (!mac_len) 180 key->mac_proto = MAC_PROTO_NONE; 181 182 invalidate_flow_key(key); 183 return 0; 184 } 185 186 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key, 187 const __be16 ethertype) 188 { 189 int err; 190 191 err = skb_mpls_pop(skb, ethertype, skb->mac_len, 192 ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET); 193 if (err) 194 return err; 195 196 if (ethertype == htons(ETH_P_TEB)) 197 key->mac_proto = MAC_PROTO_ETHERNET; 198 199 invalidate_flow_key(key); 200 return 0; 201 } 202 203 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key, 204 const __be32 *mpls_lse, const __be32 *mask) 205 { 206 struct mpls_shim_hdr *stack; 207 __be32 lse; 208 int err; 209 210 if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN)) 211 return -ENOMEM; 212 213 stack = mpls_hdr(skb); 214 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); 215 err = skb_mpls_update_lse(skb, lse); 216 if (err) 217 return err; 218 219 flow_key->mpls.lse[0] = lse; 220 return 0; 221 } 222 223 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key) 224 { 225 int err; 226 227 err = skb_vlan_pop(skb); 228 if (skb_vlan_tag_present(skb)) { 229 invalidate_flow_key(key); 230 } else { 231 key->eth.vlan.tci = 0; 232 key->eth.vlan.tpid = 0; 233 } 234 return err; 235 } 236 237 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key, 238 const struct ovs_action_push_vlan *vlan) 239 { 240 if (skb_vlan_tag_present(skb)) { 241 invalidate_flow_key(key); 242 } else { 243 key->eth.vlan.tci = vlan->vlan_tci; 244 key->eth.vlan.tpid = vlan->vlan_tpid; 245 } 246 return skb_vlan_push(skb, vlan->vlan_tpid, 247 ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK); 248 } 249 250 /* 'src' is already properly masked. */ 251 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) 252 { 253 u16 *dst = (u16 *)dst_; 254 const u16 *src = (const u16 *)src_; 255 const u16 *mask = (const u16 *)mask_; 256 257 OVS_SET_MASKED(dst[0], src[0], mask[0]); 258 OVS_SET_MASKED(dst[1], src[1], mask[1]); 259 OVS_SET_MASKED(dst[2], src[2], mask[2]); 260 } 261 262 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, 263 const struct ovs_key_ethernet *key, 264 const struct ovs_key_ethernet *mask) 265 { 266 int err; 267 268 err = skb_ensure_writable(skb, ETH_HLEN); 269 if (unlikely(err)) 270 return err; 271 272 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 273 274 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 275 mask->eth_src); 276 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 277 mask->eth_dst); 278 279 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 280 281 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 282 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); 283 return 0; 284 } 285 286 /* pop_eth does not support VLAN packets as this action is never called 287 * for them. 288 */ 289 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key) 290 { 291 int err; 292 293 err = skb_eth_pop(skb); 294 if (err) 295 return err; 296 297 /* safe right before invalidate_flow_key */ 298 key->mac_proto = MAC_PROTO_NONE; 299 invalidate_flow_key(key); 300 return 0; 301 } 302 303 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key, 304 const struct ovs_action_push_eth *ethh) 305 { 306 int err; 307 308 err = skb_eth_push(skb, ethh->addresses.eth_dst, 309 ethh->addresses.eth_src); 310 if (err) 311 return err; 312 313 /* safe right before invalidate_flow_key */ 314 key->mac_proto = MAC_PROTO_ETHERNET; 315 invalidate_flow_key(key); 316 return 0; 317 } 318 319 static noinline_for_stack int push_nsh(struct sk_buff *skb, 320 struct sw_flow_key *key, 321 const struct nlattr *a) 322 { 323 u8 buffer[NSH_HDR_MAX_LEN]; 324 struct nshhdr *nh = (struct nshhdr *)buffer; 325 int err; 326 327 err = nsh_hdr_from_nlattr(a, nh, NSH_HDR_MAX_LEN); 328 if (err) 329 return err; 330 331 err = nsh_push(skb, nh); 332 if (err) 333 return err; 334 335 /* safe right before invalidate_flow_key */ 336 key->mac_proto = MAC_PROTO_NONE; 337 invalidate_flow_key(key); 338 return 0; 339 } 340 341 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key) 342 { 343 int err; 344 345 err = nsh_pop(skb); 346 if (err) 347 return err; 348 349 /* safe right before invalidate_flow_key */ 350 if (skb->protocol == htons(ETH_P_TEB)) 351 key->mac_proto = MAC_PROTO_ETHERNET; 352 else 353 key->mac_proto = MAC_PROTO_NONE; 354 invalidate_flow_key(key); 355 return 0; 356 } 357 358 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, 359 __be32 addr, __be32 new_addr) 360 { 361 int transport_len = skb->len - skb_transport_offset(skb); 362 363 if (nh->frag_off & htons(IP_OFFSET)) 364 return; 365 366 if (nh->protocol == IPPROTO_TCP) { 367 if (likely(transport_len >= sizeof(struct tcphdr))) 368 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 369 addr, new_addr, true); 370 } else if (nh->protocol == IPPROTO_UDP) { 371 if (likely(transport_len >= sizeof(struct udphdr))) { 372 struct udphdr *uh = udp_hdr(skb); 373 374 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 375 inet_proto_csum_replace4(&uh->check, skb, 376 addr, new_addr, true); 377 if (!uh->check) 378 uh->check = CSUM_MANGLED_0; 379 } 380 } 381 } 382 } 383 384 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 385 __be32 *addr, __be32 new_addr) 386 { 387 update_ip_l4_checksum(skb, nh, *addr, new_addr); 388 csum_replace4(&nh->check, *addr, new_addr); 389 skb_clear_hash(skb); 390 ovs_ct_clear(skb, NULL); 391 *addr = new_addr; 392 } 393 394 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 395 __be32 addr[4], const __be32 new_addr[4]) 396 { 397 int transport_len = skb->len - skb_transport_offset(skb); 398 399 if (l4_proto == NEXTHDR_TCP) { 400 if (likely(transport_len >= sizeof(struct tcphdr))) 401 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 402 addr, new_addr, true); 403 } else if (l4_proto == NEXTHDR_UDP) { 404 if (likely(transport_len >= sizeof(struct udphdr))) { 405 struct udphdr *uh = udp_hdr(skb); 406 407 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 408 inet_proto_csum_replace16(&uh->check, skb, 409 addr, new_addr, true); 410 if (!uh->check) 411 uh->check = CSUM_MANGLED_0; 412 } 413 } 414 } else if (l4_proto == NEXTHDR_ICMP) { 415 if (likely(transport_len >= sizeof(struct icmp6hdr))) 416 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 417 skb, addr, new_addr, true); 418 } 419 } 420 421 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 422 const __be32 mask[4], __be32 masked[4]) 423 { 424 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 425 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 426 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 427 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 428 } 429 430 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 431 __be32 addr[4], const __be32 new_addr[4], 432 bool recalculate_csum) 433 { 434 if (recalculate_csum) 435 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 436 437 skb_clear_hash(skb); 438 ovs_ct_clear(skb, NULL); 439 memcpy(addr, new_addr, sizeof(__be32[4])); 440 } 441 442 static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask) 443 { 444 u8 old_ipv6_tclass = ipv6_get_dsfield(nh); 445 446 ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask); 447 448 if (skb->ip_summed == CHECKSUM_COMPLETE) 449 csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12), 450 (__force __wsum)(ipv6_tclass << 12)); 451 452 ipv6_change_dsfield(nh, ~mask, ipv6_tclass); 453 } 454 455 static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask) 456 { 457 u32 ofl; 458 459 ofl = nh->flow_lbl[0] << 16 | nh->flow_lbl[1] << 8 | nh->flow_lbl[2]; 460 fl = OVS_MASKED(ofl, fl, mask); 461 462 /* Bits 21-24 are always unmasked, so this retains their values. */ 463 nh->flow_lbl[0] = (u8)(fl >> 16); 464 nh->flow_lbl[1] = (u8)(fl >> 8); 465 nh->flow_lbl[2] = (u8)fl; 466 467 if (skb->ip_summed == CHECKSUM_COMPLETE) 468 csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl)); 469 } 470 471 static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask) 472 { 473 new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask); 474 475 if (skb->ip_summed == CHECKSUM_COMPLETE) 476 csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8), 477 (__force __wsum)(new_ttl << 8)); 478 nh->hop_limit = new_ttl; 479 } 480 481 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 482 u8 mask) 483 { 484 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 485 486 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 487 nh->ttl = new_ttl; 488 } 489 490 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 491 const struct ovs_key_ipv4 *key, 492 const struct ovs_key_ipv4 *mask) 493 { 494 struct iphdr *nh; 495 __be32 new_addr; 496 int err; 497 498 err = skb_ensure_writable(skb, skb_network_offset(skb) + 499 sizeof(struct iphdr)); 500 if (unlikely(err)) 501 return err; 502 503 nh = ip_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 (mask->ipv4_src) { 510 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 511 512 if (unlikely(new_addr != nh->saddr)) { 513 set_ip_addr(skb, nh, &nh->saddr, new_addr); 514 flow_key->ipv4.addr.src = new_addr; 515 } 516 } 517 if (mask->ipv4_dst) { 518 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 519 520 if (unlikely(new_addr != nh->daddr)) { 521 set_ip_addr(skb, nh, &nh->daddr, new_addr); 522 flow_key->ipv4.addr.dst = new_addr; 523 } 524 } 525 if (mask->ipv4_tos) { 526 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 527 flow_key->ip.tos = nh->tos; 528 } 529 if (mask->ipv4_ttl) { 530 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 531 flow_key->ip.ttl = nh->ttl; 532 } 533 534 return 0; 535 } 536 537 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 538 { 539 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 540 } 541 542 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 543 const struct ovs_key_ipv6 *key, 544 const struct ovs_key_ipv6 *mask) 545 { 546 struct ipv6hdr *nh; 547 int err; 548 549 err = skb_ensure_writable(skb, skb_network_offset(skb) + 550 sizeof(struct ipv6hdr)); 551 if (unlikely(err)) 552 return err; 553 554 nh = ipv6_hdr(skb); 555 556 /* Setting an IP addresses is typically only a side effect of 557 * matching on them in the current userspace implementation, so it 558 * makes sense to check if the value actually changed. 559 */ 560 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 561 __be32 *saddr = (__be32 *)&nh->saddr; 562 __be32 masked[4]; 563 564 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 565 566 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 567 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 568 true); 569 memcpy(&flow_key->ipv6.addr.src, masked, 570 sizeof(flow_key->ipv6.addr.src)); 571 } 572 } 573 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 574 unsigned int offset = 0; 575 int flags = IP6_FH_F_SKIP_RH; 576 bool recalc_csum = true; 577 __be32 *daddr = (__be32 *)&nh->daddr; 578 __be32 masked[4]; 579 580 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 581 582 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 583 if (ipv6_ext_hdr(nh->nexthdr)) 584 recalc_csum = (ipv6_find_hdr(skb, &offset, 585 NEXTHDR_ROUTING, 586 NULL, &flags) 587 != NEXTHDR_ROUTING); 588 589 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 590 recalc_csum); 591 memcpy(&flow_key->ipv6.addr.dst, masked, 592 sizeof(flow_key->ipv6.addr.dst)); 593 } 594 } 595 if (mask->ipv6_tclass) { 596 set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass); 597 flow_key->ip.tos = ipv6_get_dsfield(nh); 598 } 599 if (mask->ipv6_label) { 600 set_ipv6_fl(skb, nh, ntohl(key->ipv6_label), 601 ntohl(mask->ipv6_label)); 602 flow_key->ipv6.label = 603 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 604 } 605 if (mask->ipv6_hlimit) { 606 set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit); 607 flow_key->ip.ttl = nh->hop_limit; 608 } 609 return 0; 610 } 611 612 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, 613 const struct nlattr *a) 614 { 615 struct nshhdr *nh; 616 size_t length; 617 int err; 618 u8 flags; 619 u8 ttl; 620 int i; 621 622 struct ovs_key_nsh key; 623 struct ovs_key_nsh mask; 624 625 err = nsh_key_from_nlattr(a, &key, &mask); 626 if (err) 627 return err; 628 629 /* Make sure the NSH base header is there */ 630 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 631 return -ENOMEM; 632 633 nh = nsh_hdr(skb); 634 length = nsh_hdr_len(nh); 635 636 /* Make sure the whole NSH header is there */ 637 err = skb_ensure_writable(skb, skb_network_offset(skb) + 638 length); 639 if (unlikely(err)) 640 return err; 641 642 nh = nsh_hdr(skb); 643 skb_postpull_rcsum(skb, nh, length); 644 flags = nsh_get_flags(nh); 645 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 646 flow_key->nsh.base.flags = flags; 647 ttl = nsh_get_ttl(nh); 648 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); 649 flow_key->nsh.base.ttl = ttl; 650 nsh_set_flags_and_ttl(nh, flags, ttl); 651 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, 652 mask.base.path_hdr); 653 flow_key->nsh.base.path_hdr = nh->path_hdr; 654 switch (nh->mdtype) { 655 case NSH_M_TYPE1: 656 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { 657 nh->md1.context[i] = 658 OVS_MASKED(nh->md1.context[i], key.context[i], 659 mask.context[i]); 660 } 661 memcpy(flow_key->nsh.context, nh->md1.context, 662 sizeof(nh->md1.context)); 663 break; 664 case NSH_M_TYPE2: 665 memset(flow_key->nsh.context, 0, 666 sizeof(flow_key->nsh.context)); 667 break; 668 default: 669 return -EINVAL; 670 } 671 skb_postpush_rcsum(skb, nh, length); 672 return 0; 673 } 674 675 /* Must follow skb_ensure_writable() since that can move the skb data. */ 676 static void set_tp_port(struct sk_buff *skb, __be16 *port, 677 __be16 new_port, __sum16 *check) 678 { 679 ovs_ct_clear(skb, NULL); 680 inet_proto_csum_replace2(check, skb, *port, new_port, false); 681 *port = new_port; 682 } 683 684 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 685 const struct ovs_key_udp *key, 686 const struct ovs_key_udp *mask) 687 { 688 struct udphdr *uh; 689 __be16 src, dst; 690 int err; 691 692 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 693 sizeof(struct udphdr)); 694 if (unlikely(err)) 695 return err; 696 697 uh = udp_hdr(skb); 698 /* Either of the masks is non-zero, so do not bother checking them. */ 699 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 700 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 701 702 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 703 if (likely(src != uh->source)) { 704 set_tp_port(skb, &uh->source, src, &uh->check); 705 flow_key->tp.src = src; 706 } 707 if (likely(dst != uh->dest)) { 708 set_tp_port(skb, &uh->dest, dst, &uh->check); 709 flow_key->tp.dst = dst; 710 } 711 712 if (unlikely(!uh->check)) 713 uh->check = CSUM_MANGLED_0; 714 } else { 715 uh->source = src; 716 uh->dest = dst; 717 flow_key->tp.src = src; 718 flow_key->tp.dst = dst; 719 ovs_ct_clear(skb, NULL); 720 } 721 722 skb_clear_hash(skb); 723 724 return 0; 725 } 726 727 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 728 const struct ovs_key_tcp *key, 729 const struct ovs_key_tcp *mask) 730 { 731 struct tcphdr *th; 732 __be16 src, dst; 733 int err; 734 735 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 736 sizeof(struct tcphdr)); 737 if (unlikely(err)) 738 return err; 739 740 th = tcp_hdr(skb); 741 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 742 if (likely(src != th->source)) { 743 set_tp_port(skb, &th->source, src, &th->check); 744 flow_key->tp.src = src; 745 } 746 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 747 if (likely(dst != th->dest)) { 748 set_tp_port(skb, &th->dest, dst, &th->check); 749 flow_key->tp.dst = dst; 750 } 751 skb_clear_hash(skb); 752 753 return 0; 754 } 755 756 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 757 const struct ovs_key_sctp *key, 758 const struct ovs_key_sctp *mask) 759 { 760 unsigned int sctphoff = skb_transport_offset(skb); 761 struct sctphdr *sh; 762 __le32 old_correct_csum, new_csum, old_csum; 763 int err; 764 765 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 766 if (unlikely(err)) 767 return err; 768 769 sh = sctp_hdr(skb); 770 old_csum = sh->checksum; 771 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 772 773 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 774 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 775 776 new_csum = sctp_compute_cksum(skb, sctphoff); 777 778 /* Carry any checksum errors through. */ 779 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 780 781 skb_clear_hash(skb); 782 ovs_ct_clear(skb, NULL); 783 784 flow_key->tp.src = sh->source; 785 flow_key->tp.dst = sh->dest; 786 787 return 0; 788 } 789 790 static int ovs_vport_output(struct net *net, struct sock *sk, 791 struct sk_buff *skb) 792 { 793 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 794 struct vport *vport = data->vport; 795 796 if (skb_cow_head(skb, data->l2_len) < 0) { 797 kfree_skb_reason(skb, SKB_DROP_REASON_NOMEM); 798 return -ENOMEM; 799 } 800 801 __skb_dst_copy(skb, data->dst); 802 *OVS_CB(skb) = data->cb; 803 skb->inner_protocol = data->inner_protocol; 804 if (data->vlan_tci & VLAN_CFI_MASK) 805 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); 806 else 807 __vlan_hwaccel_clear_tag(skb); 808 809 /* Reconstruct the MAC header. */ 810 skb_push(skb, data->l2_len); 811 memcpy(skb->data, &data->l2_data, data->l2_len); 812 skb_postpush_rcsum(skb, skb->data, data->l2_len); 813 skb_reset_mac_header(skb); 814 815 if (eth_p_mpls(skb->protocol)) { 816 skb->inner_network_header = skb->network_header; 817 skb_set_network_header(skb, data->network_offset); 818 skb_reset_mac_len(skb); 819 } 820 821 ovs_vport_send(vport, skb, data->mac_proto); 822 return 0; 823 } 824 825 static unsigned int 826 ovs_dst_get_mtu(const struct dst_entry *dst) 827 { 828 return dst->dev->mtu; 829 } 830 831 static struct dst_ops ovs_dst_ops = { 832 .family = AF_UNSPEC, 833 .mtu = ovs_dst_get_mtu, 834 }; 835 836 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 837 * ovs_vport_output(), which is called once per fragmented packet. 838 */ 839 static void prepare_frag(struct vport *vport, struct sk_buff *skb, 840 u16 orig_network_offset, u8 mac_proto) 841 { 842 unsigned int hlen = skb_network_offset(skb); 843 struct ovs_frag_data *data; 844 845 data = this_cpu_ptr(&ovs_frag_data_storage); 846 data->dst = skb->_skb_refdst; 847 data->vport = vport; 848 data->cb = *OVS_CB(skb); 849 data->inner_protocol = skb->inner_protocol; 850 data->network_offset = orig_network_offset; 851 if (skb_vlan_tag_present(skb)) 852 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK; 853 else 854 data->vlan_tci = 0; 855 data->vlan_proto = skb->vlan_proto; 856 data->mac_proto = mac_proto; 857 data->l2_len = hlen; 858 memcpy(&data->l2_data, skb->data, hlen); 859 860 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 861 skb_pull(skb, hlen); 862 } 863 864 static void ovs_fragment(struct net *net, struct vport *vport, 865 struct sk_buff *skb, u16 mru, 866 struct sw_flow_key *key) 867 { 868 enum ovs_drop_reason reason; 869 u16 orig_network_offset = 0; 870 871 if (eth_p_mpls(skb->protocol)) { 872 orig_network_offset = skb_network_offset(skb); 873 skb->network_header = skb->inner_network_header; 874 } 875 876 if (skb_network_offset(skb) > MAX_L2_LEN) { 877 OVS_NLERR(1, "L2 header too long to fragment"); 878 reason = OVS_DROP_FRAG_L2_TOO_LONG; 879 goto err; 880 } 881 882 if (key->eth.type == htons(ETH_P_IP)) { 883 struct rtable ovs_rt = { 0 }; 884 unsigned long orig_dst; 885 886 prepare_frag(vport, skb, orig_network_offset, 887 ovs_key_mac_proto(key)); 888 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 889 DST_OBSOLETE_NONE, DST_NOCOUNT); 890 ovs_rt.dst.dev = vport->dev; 891 892 orig_dst = skb->_skb_refdst; 893 skb_dst_set_noref(skb, &ovs_rt.dst); 894 IPCB(skb)->frag_max_size = mru; 895 896 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 897 refdst_drop(orig_dst); 898 } else if (key->eth.type == htons(ETH_P_IPV6)) { 899 unsigned long orig_dst; 900 struct rt6_info ovs_rt; 901 902 prepare_frag(vport, skb, orig_network_offset, 903 ovs_key_mac_proto(key)); 904 memset(&ovs_rt, 0, sizeof(ovs_rt)); 905 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 906 DST_OBSOLETE_NONE, DST_NOCOUNT); 907 ovs_rt.dst.dev = vport->dev; 908 909 orig_dst = skb->_skb_refdst; 910 skb_dst_set_noref(skb, &ovs_rt.dst); 911 IP6CB(skb)->frag_max_size = mru; 912 913 ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output); 914 refdst_drop(orig_dst); 915 } else { 916 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 917 ovs_vport_name(vport), ntohs(key->eth.type), mru, 918 vport->dev->mtu); 919 reason = OVS_DROP_FRAG_INVALID_PROTO; 920 goto err; 921 } 922 923 return; 924 err: 925 ovs_kfree_skb_reason(skb, reason); 926 } 927 928 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 929 struct sw_flow_key *key) 930 { 931 struct vport *vport = ovs_vport_rcu(dp, out_port); 932 933 if (likely(vport && netif_carrier_ok(vport->dev))) { 934 u16 mru = OVS_CB(skb)->mru; 935 u32 cutlen = OVS_CB(skb)->cutlen; 936 937 if (unlikely(cutlen > 0)) { 938 if (skb->len - cutlen > ovs_mac_header_len(key)) 939 pskb_trim(skb, skb->len - cutlen); 940 else 941 pskb_trim(skb, ovs_mac_header_len(key)); 942 } 943 944 /* Need to set the pkt_type to involve the routing layer. The 945 * packet movement through the OVS datapath doesn't generally 946 * use routing, but this is needed for tunnel cases. 947 */ 948 skb->pkt_type = PACKET_OUTGOING; 949 950 if (likely(!mru || 951 (skb->len <= mru + vport->dev->hard_header_len))) { 952 ovs_vport_send(vport, skb, ovs_key_mac_proto(key)); 953 } else if (mru <= vport->dev->mtu) { 954 struct net *net = read_pnet(&dp->net); 955 956 ovs_fragment(net, vport, skb, mru, key); 957 } else { 958 kfree_skb_reason(skb, SKB_DROP_REASON_PKT_TOO_BIG); 959 } 960 } else { 961 kfree_skb_reason(skb, SKB_DROP_REASON_DEV_READY); 962 } 963 } 964 965 static int output_userspace(struct datapath *dp, struct sk_buff *skb, 966 struct sw_flow_key *key, const struct nlattr *attr, 967 const struct nlattr *actions, int actions_len, 968 uint32_t cutlen) 969 { 970 struct dp_upcall_info upcall; 971 const struct nlattr *a; 972 int rem; 973 974 memset(&upcall, 0, sizeof(upcall)); 975 upcall.cmd = OVS_PACKET_CMD_ACTION; 976 upcall.mru = OVS_CB(skb)->mru; 977 978 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 979 a = nla_next(a, &rem)) { 980 switch (nla_type(a)) { 981 case OVS_USERSPACE_ATTR_USERDATA: 982 upcall.userdata = a; 983 break; 984 985 case OVS_USERSPACE_ATTR_PID: 986 if (dp->user_features & 987 OVS_DP_F_DISPATCH_UPCALL_PER_CPU) 988 upcall.portid = 989 ovs_dp_get_upcall_portid(dp, 990 smp_processor_id()); 991 else 992 upcall.portid = nla_get_u32(a); 993 break; 994 995 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 996 /* Get out tunnel info. */ 997 struct vport *vport; 998 999 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 1000 if (vport) { 1001 int err; 1002 1003 err = dev_fill_metadata_dst(vport->dev, skb); 1004 if (!err) 1005 upcall.egress_tun_info = skb_tunnel_info(skb); 1006 } 1007 1008 break; 1009 } 1010 1011 case OVS_USERSPACE_ATTR_ACTIONS: { 1012 /* Include actions. */ 1013 upcall.actions = actions; 1014 upcall.actions_len = actions_len; 1015 break; 1016 } 1017 1018 } /* End of switch. */ 1019 } 1020 1021 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 1022 } 1023 1024 static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb, 1025 struct sw_flow_key *key, 1026 const struct nlattr *attr) 1027 { 1028 /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */ 1029 struct nlattr *actions = nla_data(attr); 1030 1031 if (nla_len(actions)) 1032 return clone_execute(dp, skb, key, 0, nla_data(actions), 1033 nla_len(actions), true, false); 1034 1035 ovs_kfree_skb_reason(skb, OVS_DROP_IP_TTL); 1036 return 0; 1037 } 1038 1039 /* When 'last' is true, sample() should always consume the 'skb'. 1040 * Otherwise, sample() should keep 'skb' intact regardless what 1041 * actions are executed within sample(). 1042 */ 1043 static int sample(struct datapath *dp, struct sk_buff *skb, 1044 struct sw_flow_key *key, const struct nlattr *attr, 1045 bool last) 1046 { 1047 struct nlattr *actions; 1048 struct nlattr *sample_arg; 1049 int rem = nla_len(attr); 1050 const struct sample_arg *arg; 1051 u32 init_probability; 1052 bool clone_flow_key; 1053 int err; 1054 1055 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ 1056 sample_arg = nla_data(attr); 1057 arg = nla_data(sample_arg); 1058 actions = nla_next(sample_arg, &rem); 1059 init_probability = OVS_CB(skb)->probability; 1060 1061 if ((arg->probability != U32_MAX) && 1062 (!arg->probability || get_random_u32() > arg->probability)) { 1063 if (last) 1064 ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); 1065 return 0; 1066 } 1067 1068 OVS_CB(skb)->probability = arg->probability; 1069 1070 clone_flow_key = !arg->exec; 1071 err = clone_execute(dp, skb, key, 0, actions, rem, last, 1072 clone_flow_key); 1073 1074 if (!last) 1075 OVS_CB(skb)->probability = init_probability; 1076 1077 return err; 1078 } 1079 1080 /* When 'last' is true, clone() should always consume the 'skb'. 1081 * Otherwise, clone() should keep 'skb' intact regardless what 1082 * actions are executed within clone(). 1083 */ 1084 static int clone(struct datapath *dp, struct sk_buff *skb, 1085 struct sw_flow_key *key, const struct nlattr *attr, 1086 bool last) 1087 { 1088 struct nlattr *actions; 1089 struct nlattr *clone_arg; 1090 int rem = nla_len(attr); 1091 bool dont_clone_flow_key; 1092 1093 /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */ 1094 clone_arg = nla_data(attr); 1095 dont_clone_flow_key = nla_get_u32(clone_arg); 1096 actions = nla_next(clone_arg, &rem); 1097 1098 return clone_execute(dp, skb, key, 0, actions, rem, last, 1099 !dont_clone_flow_key); 1100 } 1101 1102 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 1103 const struct nlattr *attr) 1104 { 1105 struct ovs_action_hash *hash_act = nla_data(attr); 1106 u32 hash = 0; 1107 1108 if (hash_act->hash_alg == OVS_HASH_ALG_L4) { 1109 /* OVS_HASH_ALG_L4 hasing type. */ 1110 hash = skb_get_hash(skb); 1111 } else if (hash_act->hash_alg == OVS_HASH_ALG_SYM_L4) { 1112 /* OVS_HASH_ALG_SYM_L4 hashing type. NOTE: this doesn't 1113 * extend past an encapsulated header. 1114 */ 1115 hash = __skb_get_hash_symmetric(skb); 1116 } 1117 1118 hash = jhash_1word(hash, hash_act->hash_basis); 1119 if (!hash) 1120 hash = 0x1; 1121 1122 key->ovs_flow_hash = hash; 1123 } 1124 1125 static int execute_set_action(struct sk_buff *skb, 1126 struct sw_flow_key *flow_key, 1127 const struct nlattr *a) 1128 { 1129 /* Only tunnel set execution is supported without a mask. */ 1130 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1131 struct ovs_tunnel_info *tun = nla_data(a); 1132 1133 skb_dst_drop(skb); 1134 dst_hold((struct dst_entry *)tun->tun_dst); 1135 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 1136 return 0; 1137 } 1138 1139 return -EINVAL; 1140 } 1141 1142 /* Mask is at the midpoint of the data. */ 1143 #define get_mask(a, type) ((const type)nla_data(a) + 1) 1144 1145 static int execute_masked_set_action(struct sk_buff *skb, 1146 struct sw_flow_key *flow_key, 1147 const struct nlattr *a) 1148 { 1149 int err = 0; 1150 1151 switch (nla_type(a)) { 1152 case OVS_KEY_ATTR_PRIORITY: 1153 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 1154 *get_mask(a, u32 *)); 1155 flow_key->phy.priority = skb->priority; 1156 break; 1157 1158 case OVS_KEY_ATTR_SKB_MARK: 1159 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 1160 flow_key->phy.skb_mark = skb->mark; 1161 break; 1162 1163 case OVS_KEY_ATTR_TUNNEL_INFO: 1164 /* Masked data not supported for tunnel. */ 1165 err = -EINVAL; 1166 break; 1167 1168 case OVS_KEY_ATTR_ETHERNET: 1169 err = set_eth_addr(skb, flow_key, nla_data(a), 1170 get_mask(a, struct ovs_key_ethernet *)); 1171 break; 1172 1173 case OVS_KEY_ATTR_NSH: 1174 err = set_nsh(skb, flow_key, a); 1175 break; 1176 1177 case OVS_KEY_ATTR_IPV4: 1178 err = set_ipv4(skb, flow_key, nla_data(a), 1179 get_mask(a, struct ovs_key_ipv4 *)); 1180 break; 1181 1182 case OVS_KEY_ATTR_IPV6: 1183 err = set_ipv6(skb, flow_key, nla_data(a), 1184 get_mask(a, struct ovs_key_ipv6 *)); 1185 break; 1186 1187 case OVS_KEY_ATTR_TCP: 1188 err = set_tcp(skb, flow_key, nla_data(a), 1189 get_mask(a, struct ovs_key_tcp *)); 1190 break; 1191 1192 case OVS_KEY_ATTR_UDP: 1193 err = set_udp(skb, flow_key, nla_data(a), 1194 get_mask(a, struct ovs_key_udp *)); 1195 break; 1196 1197 case OVS_KEY_ATTR_SCTP: 1198 err = set_sctp(skb, flow_key, nla_data(a), 1199 get_mask(a, struct ovs_key_sctp *)); 1200 break; 1201 1202 case OVS_KEY_ATTR_MPLS: 1203 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1204 __be32 *)); 1205 break; 1206 1207 case OVS_KEY_ATTR_CT_STATE: 1208 case OVS_KEY_ATTR_CT_ZONE: 1209 case OVS_KEY_ATTR_CT_MARK: 1210 case OVS_KEY_ATTR_CT_LABELS: 1211 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: 1212 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: 1213 err = -EINVAL; 1214 break; 1215 } 1216 1217 return err; 1218 } 1219 1220 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1221 struct sw_flow_key *key, 1222 const struct nlattr *a, bool last) 1223 { 1224 u32 recirc_id; 1225 1226 if (!is_flow_key_valid(key)) { 1227 int err; 1228 1229 err = ovs_flow_key_update(skb, key); 1230 if (err) 1231 return err; 1232 } 1233 BUG_ON(!is_flow_key_valid(key)); 1234 1235 recirc_id = nla_get_u32(a); 1236 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); 1237 } 1238 1239 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb, 1240 struct sw_flow_key *key, 1241 const struct nlattr *attr, bool last) 1242 { 1243 struct ovs_skb_cb *ovs_cb = OVS_CB(skb); 1244 const struct nlattr *actions, *cpl_arg; 1245 int len, max_len, rem = nla_len(attr); 1246 const struct check_pkt_len_arg *arg; 1247 bool clone_flow_key; 1248 1249 /* The first netlink attribute in 'attr' is always 1250 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'. 1251 */ 1252 cpl_arg = nla_data(attr); 1253 arg = nla_data(cpl_arg); 1254 1255 len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len; 1256 max_len = arg->pkt_len; 1257 1258 if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) || 1259 len <= max_len) { 1260 /* Second netlink attribute in 'attr' is always 1261 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'. 1262 */ 1263 actions = nla_next(cpl_arg, &rem); 1264 clone_flow_key = !arg->exec_for_lesser_equal; 1265 } else { 1266 /* Third netlink attribute in 'attr' is always 1267 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'. 1268 */ 1269 actions = nla_next(cpl_arg, &rem); 1270 actions = nla_next(actions, &rem); 1271 clone_flow_key = !arg->exec_for_greater; 1272 } 1273 1274 return clone_execute(dp, skb, key, 0, nla_data(actions), 1275 nla_len(actions), last, clone_flow_key); 1276 } 1277 1278 static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) 1279 { 1280 int err; 1281 1282 if (skb->protocol == htons(ETH_P_IPV6)) { 1283 struct ipv6hdr *nh; 1284 1285 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1286 sizeof(*nh)); 1287 if (unlikely(err)) 1288 return err; 1289 1290 nh = ipv6_hdr(skb); 1291 1292 if (nh->hop_limit <= 1) 1293 return -EHOSTUNREACH; 1294 1295 key->ip.ttl = --nh->hop_limit; 1296 } else if (skb->protocol == htons(ETH_P_IP)) { 1297 struct iphdr *nh; 1298 u8 old_ttl; 1299 1300 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1301 sizeof(*nh)); 1302 if (unlikely(err)) 1303 return err; 1304 1305 nh = ip_hdr(skb); 1306 if (nh->ttl <= 1) 1307 return -EHOSTUNREACH; 1308 1309 old_ttl = nh->ttl--; 1310 csum_replace2(&nh->check, htons(old_ttl << 8), 1311 htons(nh->ttl << 8)); 1312 key->ip.ttl = nh->ttl; 1313 } 1314 return 0; 1315 } 1316 1317 #if IS_ENABLED(CONFIG_PSAMPLE) 1318 static void execute_psample(struct datapath *dp, struct sk_buff *skb, 1319 const struct nlattr *attr) 1320 { 1321 struct psample_group psample_group = {}; 1322 struct psample_metadata md = {}; 1323 const struct nlattr *a; 1324 u32 rate; 1325 int rem; 1326 1327 nla_for_each_attr(a, nla_data(attr), nla_len(attr), rem) { 1328 switch (nla_type(a)) { 1329 case OVS_PSAMPLE_ATTR_GROUP: 1330 psample_group.group_num = nla_get_u32(a); 1331 break; 1332 1333 case OVS_PSAMPLE_ATTR_COOKIE: 1334 md.user_cookie = nla_data(a); 1335 md.user_cookie_len = nla_len(a); 1336 break; 1337 } 1338 } 1339 1340 psample_group.net = ovs_dp_get_net(dp); 1341 md.in_ifindex = OVS_CB(skb)->input_vport->dev->ifindex; 1342 md.trunc_size = skb->len - OVS_CB(skb)->cutlen; 1343 md.rate_as_probability = 1; 1344 1345 rate = OVS_CB(skb)->probability ? OVS_CB(skb)->probability : U32_MAX; 1346 1347 psample_sample_packet(&psample_group, skb, rate, &md); 1348 } 1349 #else 1350 static void execute_psample(struct datapath *dp, struct sk_buff *skb, 1351 const struct nlattr *attr) 1352 {} 1353 #endif 1354 1355 /* Execute a list of actions against 'skb'. */ 1356 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1357 struct sw_flow_key *key, 1358 const struct nlattr *attr, int len) 1359 { 1360 const struct nlattr *a; 1361 int rem; 1362 1363 for (a = attr, rem = len; rem > 0; 1364 a = nla_next(a, &rem)) { 1365 int err = 0; 1366 1367 if (trace_ovs_do_execute_action_enabled()) 1368 trace_ovs_do_execute_action(dp, skb, key, a, rem); 1369 1370 /* Actions that rightfully have to consume the skb should do it 1371 * and return directly. 1372 */ 1373 switch (nla_type(a)) { 1374 case OVS_ACTION_ATTR_OUTPUT: { 1375 int port = nla_get_u32(a); 1376 struct sk_buff *clone; 1377 1378 /* Every output action needs a separate clone 1379 * of 'skb', In case the output action is the 1380 * last action, cloning can be avoided. 1381 */ 1382 if (nla_is_last(a, rem)) { 1383 do_output(dp, skb, port, key); 1384 /* 'skb' has been used for output. 1385 */ 1386 return 0; 1387 } 1388 1389 clone = skb_clone(skb, GFP_ATOMIC); 1390 if (clone) 1391 do_output(dp, clone, port, key); 1392 OVS_CB(skb)->cutlen = 0; 1393 break; 1394 } 1395 1396 case OVS_ACTION_ATTR_TRUNC: { 1397 struct ovs_action_trunc *trunc = nla_data(a); 1398 1399 if (skb->len > trunc->max_len) 1400 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1401 break; 1402 } 1403 1404 case OVS_ACTION_ATTR_USERSPACE: 1405 output_userspace(dp, skb, key, a, attr, 1406 len, OVS_CB(skb)->cutlen); 1407 OVS_CB(skb)->cutlen = 0; 1408 if (nla_is_last(a, rem)) { 1409 consume_skb(skb); 1410 return 0; 1411 } 1412 break; 1413 1414 case OVS_ACTION_ATTR_HASH: 1415 execute_hash(skb, key, a); 1416 break; 1417 1418 case OVS_ACTION_ATTR_PUSH_MPLS: { 1419 struct ovs_action_push_mpls *mpls = nla_data(a); 1420 1421 err = push_mpls(skb, key, mpls->mpls_lse, 1422 mpls->mpls_ethertype, skb->mac_len); 1423 break; 1424 } 1425 case OVS_ACTION_ATTR_ADD_MPLS: { 1426 struct ovs_action_add_mpls *mpls = nla_data(a); 1427 __u16 mac_len = 0; 1428 1429 if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK) 1430 mac_len = skb->mac_len; 1431 1432 err = push_mpls(skb, key, mpls->mpls_lse, 1433 mpls->mpls_ethertype, mac_len); 1434 break; 1435 } 1436 case OVS_ACTION_ATTR_POP_MPLS: 1437 err = pop_mpls(skb, key, nla_get_be16(a)); 1438 break; 1439 1440 case OVS_ACTION_ATTR_PUSH_VLAN: 1441 err = push_vlan(skb, key, nla_data(a)); 1442 break; 1443 1444 case OVS_ACTION_ATTR_POP_VLAN: 1445 err = pop_vlan(skb, key); 1446 break; 1447 1448 case OVS_ACTION_ATTR_RECIRC: { 1449 bool last = nla_is_last(a, rem); 1450 1451 err = execute_recirc(dp, skb, key, a, last); 1452 if (last) { 1453 /* If this is the last action, the skb has 1454 * been consumed or freed. 1455 * Return immediately. 1456 */ 1457 return err; 1458 } 1459 break; 1460 } 1461 1462 case OVS_ACTION_ATTR_SET: 1463 err = execute_set_action(skb, key, nla_data(a)); 1464 break; 1465 1466 case OVS_ACTION_ATTR_SET_MASKED: 1467 case OVS_ACTION_ATTR_SET_TO_MASKED: 1468 err = execute_masked_set_action(skb, key, nla_data(a)); 1469 break; 1470 1471 case OVS_ACTION_ATTR_SAMPLE: { 1472 bool last = nla_is_last(a, rem); 1473 1474 err = sample(dp, skb, key, a, last); 1475 if (last) 1476 return err; 1477 1478 break; 1479 } 1480 1481 case OVS_ACTION_ATTR_CT: 1482 if (!is_flow_key_valid(key)) { 1483 err = ovs_flow_key_update(skb, key); 1484 if (err) 1485 return err; 1486 } 1487 1488 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1489 nla_data(a)); 1490 1491 /* Hide stolen IP fragments from user space. */ 1492 if (err) 1493 return err == -EINPROGRESS ? 0 : err; 1494 break; 1495 1496 case OVS_ACTION_ATTR_CT_CLEAR: 1497 err = ovs_ct_clear(skb, key); 1498 break; 1499 1500 case OVS_ACTION_ATTR_PUSH_ETH: 1501 err = push_eth(skb, key, nla_data(a)); 1502 break; 1503 1504 case OVS_ACTION_ATTR_POP_ETH: 1505 err = pop_eth(skb, key); 1506 break; 1507 1508 case OVS_ACTION_ATTR_PUSH_NSH: 1509 err = push_nsh(skb, key, nla_data(a)); 1510 break; 1511 1512 case OVS_ACTION_ATTR_POP_NSH: 1513 err = pop_nsh(skb, key); 1514 break; 1515 1516 case OVS_ACTION_ATTR_METER: 1517 if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { 1518 ovs_kfree_skb_reason(skb, OVS_DROP_METER); 1519 return 0; 1520 } 1521 break; 1522 1523 case OVS_ACTION_ATTR_CLONE: { 1524 bool last = nla_is_last(a, rem); 1525 1526 err = clone(dp, skb, key, a, last); 1527 if (last) 1528 return err; 1529 1530 break; 1531 } 1532 1533 case OVS_ACTION_ATTR_CHECK_PKT_LEN: { 1534 bool last = nla_is_last(a, rem); 1535 1536 err = execute_check_pkt_len(dp, skb, key, a, last); 1537 if (last) 1538 return err; 1539 1540 break; 1541 } 1542 1543 case OVS_ACTION_ATTR_DEC_TTL: 1544 err = execute_dec_ttl(skb, key); 1545 if (err == -EHOSTUNREACH) 1546 return dec_ttl_exception_handler(dp, skb, 1547 key, a); 1548 break; 1549 1550 case OVS_ACTION_ATTR_DROP: { 1551 enum ovs_drop_reason reason = nla_get_u32(a) 1552 ? OVS_DROP_EXPLICIT_WITH_ERROR 1553 : OVS_DROP_EXPLICIT; 1554 1555 ovs_kfree_skb_reason(skb, reason); 1556 return 0; 1557 } 1558 1559 case OVS_ACTION_ATTR_PSAMPLE: 1560 execute_psample(dp, skb, a); 1561 OVS_CB(skb)->cutlen = 0; 1562 if (nla_is_last(a, rem)) { 1563 consume_skb(skb); 1564 return 0; 1565 } 1566 break; 1567 } 1568 1569 if (unlikely(err)) { 1570 ovs_kfree_skb_reason(skb, OVS_DROP_ACTION_ERROR); 1571 return err; 1572 } 1573 } 1574 1575 ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); 1576 return 0; 1577 } 1578 1579 /* Execute the actions on the clone of the packet. The effect of the 1580 * execution does not affect the original 'skb' nor the original 'key'. 1581 * 1582 * The execution may be deferred in case the actions can not be executed 1583 * immediately. 1584 */ 1585 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 1586 struct sw_flow_key *key, u32 recirc_id, 1587 const struct nlattr *actions, int len, 1588 bool last, bool clone_flow_key) 1589 { 1590 struct deferred_action *da; 1591 struct sw_flow_key *clone; 1592 1593 skb = last ? skb : skb_clone(skb, GFP_ATOMIC); 1594 if (!skb) { 1595 /* Out of memory, skip this action. 1596 */ 1597 return 0; 1598 } 1599 1600 /* When clone_flow_key is false, the 'key' will not be change 1601 * by the actions, then the 'key' can be used directly. 1602 * Otherwise, try to clone key from the next recursion level of 1603 * 'flow_keys'. If clone is successful, execute the actions 1604 * without deferring. 1605 */ 1606 clone = clone_flow_key ? clone_key(key) : key; 1607 if (clone) { 1608 int err = 0; 1609 1610 if (actions) { /* Sample action */ 1611 if (clone_flow_key) 1612 __this_cpu_inc(exec_actions_level); 1613 1614 err = do_execute_actions(dp, skb, clone, 1615 actions, len); 1616 1617 if (clone_flow_key) 1618 __this_cpu_dec(exec_actions_level); 1619 } else { /* Recirc action */ 1620 clone->recirc_id = recirc_id; 1621 ovs_dp_process_packet(skb, clone); 1622 } 1623 return err; 1624 } 1625 1626 /* Out of 'flow_keys' space. Defer actions */ 1627 da = add_deferred_actions(skb, key, actions, len); 1628 if (da) { 1629 if (!actions) { /* Recirc action */ 1630 key = &da->pkt_key; 1631 key->recirc_id = recirc_id; 1632 } 1633 } else { 1634 /* Out of per CPU action FIFO space. Drop the 'skb' and 1635 * log an error. 1636 */ 1637 ovs_kfree_skb_reason(skb, OVS_DROP_DEFERRED_LIMIT); 1638 1639 if (net_ratelimit()) { 1640 if (actions) { /* Sample action */ 1641 pr_warn("%s: deferred action limit reached, drop sample action\n", 1642 ovs_dp_name(dp)); 1643 } else { /* Recirc action */ 1644 pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n", 1645 ovs_dp_name(dp), recirc_id); 1646 } 1647 } 1648 } 1649 return 0; 1650 } 1651 1652 static void process_deferred_actions(struct datapath *dp) 1653 { 1654 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1655 1656 /* Do not touch the FIFO in case there is no deferred actions. */ 1657 if (action_fifo_is_empty(fifo)) 1658 return; 1659 1660 /* Finishing executing all deferred actions. */ 1661 do { 1662 struct deferred_action *da = action_fifo_get(fifo); 1663 struct sk_buff *skb = da->skb; 1664 struct sw_flow_key *key = &da->pkt_key; 1665 const struct nlattr *actions = da->actions; 1666 int actions_len = da->actions_len; 1667 1668 if (actions) 1669 do_execute_actions(dp, skb, key, actions, actions_len); 1670 else 1671 ovs_dp_process_packet(skb, key); 1672 } while (!action_fifo_is_empty(fifo)); 1673 1674 /* Reset FIFO for the next packet. */ 1675 action_fifo_init(fifo); 1676 } 1677 1678 /* Execute a list of actions against 'skb'. */ 1679 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1680 const struct sw_flow_actions *acts, 1681 struct sw_flow_key *key) 1682 { 1683 int err, level; 1684 1685 level = __this_cpu_inc_return(exec_actions_level); 1686 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1687 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1688 ovs_dp_name(dp)); 1689 ovs_kfree_skb_reason(skb, OVS_DROP_RECURSION_LIMIT); 1690 err = -ENETDOWN; 1691 goto out; 1692 } 1693 1694 OVS_CB(skb)->acts_origlen = acts->orig_len; 1695 err = do_execute_actions(dp, skb, key, 1696 acts->actions, acts->actions_len); 1697 1698 if (level == 1) 1699 process_deferred_actions(dp); 1700 1701 out: 1702 __this_cpu_dec(exec_actions_level); 1703 return err; 1704 } 1705 1706 int action_fifos_init(void) 1707 { 1708 action_fifos = alloc_percpu(struct action_fifo); 1709 if (!action_fifos) 1710 return -ENOMEM; 1711 1712 flow_keys = alloc_percpu(struct action_flow_keys); 1713 if (!flow_keys) { 1714 free_percpu(action_fifos); 1715 return -ENOMEM; 1716 } 1717 1718 return 0; 1719 } 1720 1721 void action_fifos_exit(void) 1722 { 1723 free_percpu(action_fifos); 1724 free_percpu(flow_keys); 1725 } 1726