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 int err; 241 242 if (skb_vlan_tag_present(skb)) { 243 invalidate_flow_key(key); 244 } else { 245 key->eth.vlan.tci = vlan->vlan_tci; 246 key->eth.vlan.tpid = vlan->vlan_tpid; 247 } 248 err = skb_vlan_push(skb, vlan->vlan_tpid, 249 ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK); 250 skb_reset_mac_len(skb); 251 return err; 252 } 253 254 /* 'src' is already properly masked. */ 255 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) 256 { 257 u16 *dst = (u16 *)dst_; 258 const u16 *src = (const u16 *)src_; 259 const u16 *mask = (const u16 *)mask_; 260 261 OVS_SET_MASKED(dst[0], src[0], mask[0]); 262 OVS_SET_MASKED(dst[1], src[1], mask[1]); 263 OVS_SET_MASKED(dst[2], src[2], mask[2]); 264 } 265 266 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, 267 const struct ovs_key_ethernet *key, 268 const struct ovs_key_ethernet *mask) 269 { 270 int err; 271 272 err = skb_ensure_writable(skb, ETH_HLEN); 273 if (unlikely(err)) 274 return err; 275 276 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 277 278 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 279 mask->eth_src); 280 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 281 mask->eth_dst); 282 283 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 284 285 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 286 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); 287 return 0; 288 } 289 290 /* pop_eth does not support VLAN packets as this action is never called 291 * for them. 292 */ 293 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key) 294 { 295 int err; 296 297 err = skb_eth_pop(skb); 298 if (err) 299 return err; 300 301 /* safe right before invalidate_flow_key */ 302 key->mac_proto = MAC_PROTO_NONE; 303 invalidate_flow_key(key); 304 return 0; 305 } 306 307 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key, 308 const struct ovs_action_push_eth *ethh) 309 { 310 int err; 311 312 err = skb_eth_push(skb, ethh->addresses.eth_dst, 313 ethh->addresses.eth_src); 314 if (err) 315 return err; 316 317 /* safe right before invalidate_flow_key */ 318 key->mac_proto = MAC_PROTO_ETHERNET; 319 invalidate_flow_key(key); 320 return 0; 321 } 322 323 static noinline_for_stack int push_nsh(struct sk_buff *skb, 324 struct sw_flow_key *key, 325 const struct nlattr *a) 326 { 327 u8 buffer[NSH_HDR_MAX_LEN]; 328 struct nshhdr *nh = (struct nshhdr *)buffer; 329 int err; 330 331 err = nsh_hdr_from_nlattr(a, nh, NSH_HDR_MAX_LEN); 332 if (err) 333 return err; 334 335 err = nsh_push(skb, nh); 336 if (err) 337 return err; 338 339 /* safe right before invalidate_flow_key */ 340 key->mac_proto = MAC_PROTO_NONE; 341 invalidate_flow_key(key); 342 return 0; 343 } 344 345 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key) 346 { 347 int err; 348 349 err = nsh_pop(skb); 350 if (err) 351 return err; 352 353 /* safe right before invalidate_flow_key */ 354 if (skb->protocol == htons(ETH_P_TEB)) 355 key->mac_proto = MAC_PROTO_ETHERNET; 356 else 357 key->mac_proto = MAC_PROTO_NONE; 358 invalidate_flow_key(key); 359 return 0; 360 } 361 362 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, 363 __be32 addr, __be32 new_addr) 364 { 365 int transport_len = skb->len - skb_transport_offset(skb); 366 367 if (nh->frag_off & htons(IP_OFFSET)) 368 return; 369 370 if (nh->protocol == IPPROTO_TCP) { 371 if (likely(transport_len >= sizeof(struct tcphdr))) 372 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 373 addr, new_addr, true); 374 } else if (nh->protocol == IPPROTO_UDP) { 375 if (likely(transport_len >= sizeof(struct udphdr))) { 376 struct udphdr *uh = udp_hdr(skb); 377 378 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 379 inet_proto_csum_replace4(&uh->check, skb, 380 addr, new_addr, true); 381 if (!uh->check) 382 uh->check = CSUM_MANGLED_0; 383 } 384 } 385 } 386 } 387 388 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 389 __be32 *addr, __be32 new_addr) 390 { 391 update_ip_l4_checksum(skb, nh, *addr, new_addr); 392 csum_replace4(&nh->check, *addr, new_addr); 393 skb_clear_hash(skb); 394 ovs_ct_clear(skb, NULL); 395 *addr = new_addr; 396 } 397 398 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 399 __be32 addr[4], const __be32 new_addr[4]) 400 { 401 int transport_len = skb->len - skb_transport_offset(skb); 402 403 if (l4_proto == NEXTHDR_TCP) { 404 if (likely(transport_len >= sizeof(struct tcphdr))) 405 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 406 addr, new_addr, true); 407 } else if (l4_proto == NEXTHDR_UDP) { 408 if (likely(transport_len >= sizeof(struct udphdr))) { 409 struct udphdr *uh = udp_hdr(skb); 410 411 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 412 inet_proto_csum_replace16(&uh->check, skb, 413 addr, new_addr, true); 414 if (!uh->check) 415 uh->check = CSUM_MANGLED_0; 416 } 417 } 418 } else if (l4_proto == NEXTHDR_ICMP) { 419 if (likely(transport_len >= sizeof(struct icmp6hdr))) 420 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 421 skb, addr, new_addr, true); 422 } 423 } 424 425 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 426 const __be32 mask[4], __be32 masked[4]) 427 { 428 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 429 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 430 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 431 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 432 } 433 434 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 435 __be32 addr[4], const __be32 new_addr[4], 436 bool recalculate_csum) 437 { 438 if (recalculate_csum) 439 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 440 441 skb_clear_hash(skb); 442 ovs_ct_clear(skb, NULL); 443 memcpy(addr, new_addr, sizeof(__be32[4])); 444 } 445 446 static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask) 447 { 448 u8 old_ipv6_tclass = ipv6_get_dsfield(nh); 449 450 ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask); 451 452 if (skb->ip_summed == CHECKSUM_COMPLETE) 453 csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12), 454 (__force __wsum)(ipv6_tclass << 12)); 455 456 ipv6_change_dsfield(nh, ~mask, ipv6_tclass); 457 } 458 459 static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask) 460 { 461 u32 ofl; 462 463 ofl = nh->flow_lbl[0] << 16 | nh->flow_lbl[1] << 8 | nh->flow_lbl[2]; 464 fl = OVS_MASKED(ofl, fl, mask); 465 466 /* Bits 21-24 are always unmasked, so this retains their values. */ 467 nh->flow_lbl[0] = (u8)(fl >> 16); 468 nh->flow_lbl[1] = (u8)(fl >> 8); 469 nh->flow_lbl[2] = (u8)fl; 470 471 if (skb->ip_summed == CHECKSUM_COMPLETE) 472 csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl)); 473 } 474 475 static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask) 476 { 477 new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask); 478 479 if (skb->ip_summed == CHECKSUM_COMPLETE) 480 csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8), 481 (__force __wsum)(new_ttl << 8)); 482 nh->hop_limit = new_ttl; 483 } 484 485 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 486 u8 mask) 487 { 488 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 489 490 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 491 nh->ttl = new_ttl; 492 } 493 494 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 495 const struct ovs_key_ipv4 *key, 496 const struct ovs_key_ipv4 *mask) 497 { 498 struct iphdr *nh; 499 __be32 new_addr; 500 int err; 501 502 err = skb_ensure_writable(skb, skb_network_offset(skb) + 503 sizeof(struct iphdr)); 504 if (unlikely(err)) 505 return err; 506 507 nh = ip_hdr(skb); 508 509 /* Setting an IP addresses is typically only a side effect of 510 * matching on them in the current userspace implementation, so it 511 * makes sense to check if the value actually changed. 512 */ 513 if (mask->ipv4_src) { 514 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 515 516 if (unlikely(new_addr != nh->saddr)) { 517 set_ip_addr(skb, nh, &nh->saddr, new_addr); 518 flow_key->ipv4.addr.src = new_addr; 519 } 520 } 521 if (mask->ipv4_dst) { 522 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 523 524 if (unlikely(new_addr != nh->daddr)) { 525 set_ip_addr(skb, nh, &nh->daddr, new_addr); 526 flow_key->ipv4.addr.dst = new_addr; 527 } 528 } 529 if (mask->ipv4_tos) { 530 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 531 flow_key->ip.tos = nh->tos; 532 } 533 if (mask->ipv4_ttl) { 534 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 535 flow_key->ip.ttl = nh->ttl; 536 } 537 538 return 0; 539 } 540 541 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 542 { 543 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 544 } 545 546 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 547 const struct ovs_key_ipv6 *key, 548 const struct ovs_key_ipv6 *mask) 549 { 550 struct ipv6hdr *nh; 551 int err; 552 553 err = skb_ensure_writable(skb, skb_network_offset(skb) + 554 sizeof(struct ipv6hdr)); 555 if (unlikely(err)) 556 return err; 557 558 nh = ipv6_hdr(skb); 559 560 /* Setting an IP addresses is typically only a side effect of 561 * matching on them in the current userspace implementation, so it 562 * makes sense to check if the value actually changed. 563 */ 564 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 565 __be32 *saddr = (__be32 *)&nh->saddr; 566 __be32 masked[4]; 567 568 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 569 570 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 571 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 572 true); 573 memcpy(&flow_key->ipv6.addr.src, masked, 574 sizeof(flow_key->ipv6.addr.src)); 575 } 576 } 577 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 578 unsigned int offset = 0; 579 int flags = IP6_FH_F_SKIP_RH; 580 bool recalc_csum = true; 581 __be32 *daddr = (__be32 *)&nh->daddr; 582 __be32 masked[4]; 583 584 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 585 586 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 587 if (ipv6_ext_hdr(nh->nexthdr)) 588 recalc_csum = (ipv6_find_hdr(skb, &offset, 589 NEXTHDR_ROUTING, 590 NULL, &flags) 591 != NEXTHDR_ROUTING); 592 593 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 594 recalc_csum); 595 memcpy(&flow_key->ipv6.addr.dst, masked, 596 sizeof(flow_key->ipv6.addr.dst)); 597 } 598 } 599 if (mask->ipv6_tclass) { 600 set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass); 601 flow_key->ip.tos = ipv6_get_dsfield(nh); 602 } 603 if (mask->ipv6_label) { 604 set_ipv6_fl(skb, nh, ntohl(key->ipv6_label), 605 ntohl(mask->ipv6_label)); 606 flow_key->ipv6.label = 607 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 608 } 609 if (mask->ipv6_hlimit) { 610 set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit); 611 flow_key->ip.ttl = nh->hop_limit; 612 } 613 return 0; 614 } 615 616 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, 617 const struct nlattr *a) 618 { 619 struct nshhdr *nh; 620 size_t length; 621 int err; 622 u8 flags; 623 u8 ttl; 624 int i; 625 626 struct ovs_key_nsh key; 627 struct ovs_key_nsh mask; 628 629 err = nsh_key_from_nlattr(a, &key, &mask); 630 if (err) 631 return err; 632 633 /* Make sure the NSH base header is there */ 634 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 635 return -ENOMEM; 636 637 nh = nsh_hdr(skb); 638 length = nsh_hdr_len(nh); 639 640 /* Make sure the whole NSH header is there */ 641 err = skb_ensure_writable(skb, skb_network_offset(skb) + 642 length); 643 if (unlikely(err)) 644 return err; 645 646 nh = nsh_hdr(skb); 647 skb_postpull_rcsum(skb, nh, length); 648 flags = nsh_get_flags(nh); 649 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 650 flow_key->nsh.base.flags = flags; 651 ttl = nsh_get_ttl(nh); 652 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); 653 flow_key->nsh.base.ttl = ttl; 654 nsh_set_flags_and_ttl(nh, flags, ttl); 655 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, 656 mask.base.path_hdr); 657 flow_key->nsh.base.path_hdr = nh->path_hdr; 658 switch (nh->mdtype) { 659 case NSH_M_TYPE1: 660 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { 661 nh->md1.context[i] = 662 OVS_MASKED(nh->md1.context[i], key.context[i], 663 mask.context[i]); 664 } 665 memcpy(flow_key->nsh.context, nh->md1.context, 666 sizeof(nh->md1.context)); 667 break; 668 case NSH_M_TYPE2: 669 memset(flow_key->nsh.context, 0, 670 sizeof(flow_key->nsh.context)); 671 break; 672 default: 673 return -EINVAL; 674 } 675 skb_postpush_rcsum(skb, nh, length); 676 return 0; 677 } 678 679 /* Must follow skb_ensure_writable() since that can move the skb data. */ 680 static void set_tp_port(struct sk_buff *skb, __be16 *port, 681 __be16 new_port, __sum16 *check) 682 { 683 ovs_ct_clear(skb, NULL); 684 inet_proto_csum_replace2(check, skb, *port, new_port, false); 685 *port = new_port; 686 } 687 688 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 689 const struct ovs_key_udp *key, 690 const struct ovs_key_udp *mask) 691 { 692 struct udphdr *uh; 693 __be16 src, dst; 694 int err; 695 696 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 697 sizeof(struct udphdr)); 698 if (unlikely(err)) 699 return err; 700 701 uh = udp_hdr(skb); 702 /* Either of the masks is non-zero, so do not bother checking them. */ 703 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 704 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 705 706 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 707 if (likely(src != uh->source)) { 708 set_tp_port(skb, &uh->source, src, &uh->check); 709 flow_key->tp.src = src; 710 } 711 if (likely(dst != uh->dest)) { 712 set_tp_port(skb, &uh->dest, dst, &uh->check); 713 flow_key->tp.dst = dst; 714 } 715 716 if (unlikely(!uh->check)) 717 uh->check = CSUM_MANGLED_0; 718 } else { 719 uh->source = src; 720 uh->dest = dst; 721 flow_key->tp.src = src; 722 flow_key->tp.dst = dst; 723 ovs_ct_clear(skb, NULL); 724 } 725 726 skb_clear_hash(skb); 727 728 return 0; 729 } 730 731 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 732 const struct ovs_key_tcp *key, 733 const struct ovs_key_tcp *mask) 734 { 735 struct tcphdr *th; 736 __be16 src, dst; 737 int err; 738 739 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 740 sizeof(struct tcphdr)); 741 if (unlikely(err)) 742 return err; 743 744 th = tcp_hdr(skb); 745 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 746 if (likely(src != th->source)) { 747 set_tp_port(skb, &th->source, src, &th->check); 748 flow_key->tp.src = src; 749 } 750 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 751 if (likely(dst != th->dest)) { 752 set_tp_port(skb, &th->dest, dst, &th->check); 753 flow_key->tp.dst = dst; 754 } 755 skb_clear_hash(skb); 756 757 return 0; 758 } 759 760 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 761 const struct ovs_key_sctp *key, 762 const struct ovs_key_sctp *mask) 763 { 764 unsigned int sctphoff = skb_transport_offset(skb); 765 struct sctphdr *sh; 766 __le32 old_correct_csum, new_csum, old_csum; 767 int err; 768 769 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 770 if (unlikely(err)) 771 return err; 772 773 sh = sctp_hdr(skb); 774 old_csum = sh->checksum; 775 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 776 777 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 778 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 779 780 new_csum = sctp_compute_cksum(skb, sctphoff); 781 782 /* Carry any checksum errors through. */ 783 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 784 785 skb_clear_hash(skb); 786 ovs_ct_clear(skb, NULL); 787 788 flow_key->tp.src = sh->source; 789 flow_key->tp.dst = sh->dest; 790 791 return 0; 792 } 793 794 static int ovs_vport_output(struct net *net, struct sock *sk, 795 struct sk_buff *skb) 796 { 797 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 798 struct vport *vport = data->vport; 799 800 if (skb_cow_head(skb, data->l2_len) < 0) { 801 kfree_skb_reason(skb, SKB_DROP_REASON_NOMEM); 802 return -ENOMEM; 803 } 804 805 __skb_dst_copy(skb, data->dst); 806 *OVS_CB(skb) = data->cb; 807 skb->inner_protocol = data->inner_protocol; 808 if (data->vlan_tci & VLAN_CFI_MASK) 809 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); 810 else 811 __vlan_hwaccel_clear_tag(skb); 812 813 /* Reconstruct the MAC header. */ 814 skb_push(skb, data->l2_len); 815 memcpy(skb->data, &data->l2_data, data->l2_len); 816 skb_postpush_rcsum(skb, skb->data, data->l2_len); 817 skb_reset_mac_header(skb); 818 819 if (eth_p_mpls(skb->protocol)) { 820 skb->inner_network_header = skb->network_header; 821 skb_set_network_header(skb, data->network_offset); 822 skb_reset_mac_len(skb); 823 } 824 825 ovs_vport_send(vport, skb, data->mac_proto); 826 return 0; 827 } 828 829 static unsigned int 830 ovs_dst_get_mtu(const struct dst_entry *dst) 831 { 832 return dst->dev->mtu; 833 } 834 835 static struct dst_ops ovs_dst_ops = { 836 .family = AF_UNSPEC, 837 .mtu = ovs_dst_get_mtu, 838 }; 839 840 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 841 * ovs_vport_output(), which is called once per fragmented packet. 842 */ 843 static void prepare_frag(struct vport *vport, struct sk_buff *skb, 844 u16 orig_network_offset, u8 mac_proto) 845 { 846 unsigned int hlen = skb_network_offset(skb); 847 struct ovs_frag_data *data; 848 849 data = this_cpu_ptr(&ovs_frag_data_storage); 850 data->dst = skb->_skb_refdst; 851 data->vport = vport; 852 data->cb = *OVS_CB(skb); 853 data->inner_protocol = skb->inner_protocol; 854 data->network_offset = orig_network_offset; 855 if (skb_vlan_tag_present(skb)) 856 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK; 857 else 858 data->vlan_tci = 0; 859 data->vlan_proto = skb->vlan_proto; 860 data->mac_proto = mac_proto; 861 data->l2_len = hlen; 862 memcpy(&data->l2_data, skb->data, hlen); 863 864 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 865 skb_pull(skb, hlen); 866 } 867 868 static void ovs_fragment(struct net *net, struct vport *vport, 869 struct sk_buff *skb, u16 mru, 870 struct sw_flow_key *key) 871 { 872 enum ovs_drop_reason reason; 873 u16 orig_network_offset = 0; 874 875 if (eth_p_mpls(skb->protocol)) { 876 orig_network_offset = skb_network_offset(skb); 877 skb->network_header = skb->inner_network_header; 878 } 879 880 if (skb_network_offset(skb) > MAX_L2_LEN) { 881 OVS_NLERR(1, "L2 header too long to fragment"); 882 reason = OVS_DROP_FRAG_L2_TOO_LONG; 883 goto err; 884 } 885 886 if (key->eth.type == htons(ETH_P_IP)) { 887 struct rtable ovs_rt = { 0 }; 888 unsigned long orig_dst; 889 890 prepare_frag(vport, skb, orig_network_offset, 891 ovs_key_mac_proto(key)); 892 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 893 DST_OBSOLETE_NONE, DST_NOCOUNT); 894 ovs_rt.dst.dev = vport->dev; 895 896 orig_dst = skb->_skb_refdst; 897 skb_dst_set_noref(skb, &ovs_rt.dst); 898 IPCB(skb)->frag_max_size = mru; 899 900 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 901 refdst_drop(orig_dst); 902 } else if (key->eth.type == htons(ETH_P_IPV6)) { 903 unsigned long orig_dst; 904 struct rt6_info ovs_rt; 905 906 prepare_frag(vport, skb, orig_network_offset, 907 ovs_key_mac_proto(key)); 908 memset(&ovs_rt, 0, sizeof(ovs_rt)); 909 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 910 DST_OBSOLETE_NONE, DST_NOCOUNT); 911 ovs_rt.dst.dev = vport->dev; 912 913 orig_dst = skb->_skb_refdst; 914 skb_dst_set_noref(skb, &ovs_rt.dst); 915 IP6CB(skb)->frag_max_size = mru; 916 917 ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output); 918 refdst_drop(orig_dst); 919 } else { 920 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 921 ovs_vport_name(vport), ntohs(key->eth.type), mru, 922 vport->dev->mtu); 923 reason = OVS_DROP_FRAG_INVALID_PROTO; 924 goto err; 925 } 926 927 return; 928 err: 929 ovs_kfree_skb_reason(skb, reason); 930 } 931 932 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 933 struct sw_flow_key *key) 934 { 935 struct vport *vport = ovs_vport_rcu(dp, out_port); 936 937 if (likely(vport && 938 netif_running(vport->dev) && 939 netif_carrier_ok(vport->dev))) { 940 u16 mru = OVS_CB(skb)->mru; 941 u32 cutlen = OVS_CB(skb)->cutlen; 942 943 if (unlikely(cutlen > 0)) { 944 if (skb->len - cutlen > ovs_mac_header_len(key)) 945 pskb_trim(skb, skb->len - cutlen); 946 else 947 pskb_trim(skb, ovs_mac_header_len(key)); 948 } 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 nla_for_each_nested(a, attr, rem) { 979 switch (nla_type(a)) { 980 case OVS_USERSPACE_ATTR_USERDATA: 981 upcall.userdata = a; 982 break; 983 984 case OVS_USERSPACE_ATTR_PID: 985 if (dp->user_features & 986 OVS_DP_F_DISPATCH_UPCALL_PER_CPU) 987 upcall.portid = 988 ovs_dp_get_upcall_portid(dp, 989 smp_processor_id()); 990 else 991 upcall.portid = nla_get_u32(a); 992 break; 993 994 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 995 /* Get out tunnel info. */ 996 struct vport *vport; 997 998 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 999 if (vport) { 1000 int err; 1001 1002 err = dev_fill_metadata_dst(vport->dev, skb); 1003 if (!err) 1004 upcall.egress_tun_info = skb_tunnel_info(skb); 1005 } 1006 1007 break; 1008 } 1009 1010 case OVS_USERSPACE_ATTR_ACTIONS: { 1011 /* Include actions. */ 1012 upcall.actions = actions; 1013 upcall.actions_len = actions_len; 1014 break; 1015 } 1016 1017 } /* End of switch. */ 1018 } 1019 1020 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 1021 } 1022 1023 static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb, 1024 struct sw_flow_key *key, 1025 const struct nlattr *attr) 1026 { 1027 /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */ 1028 struct nlattr *actions = nla_data(attr); 1029 1030 if (nla_len(actions)) 1031 return clone_execute(dp, skb, key, 0, nla_data(actions), 1032 nla_len(actions), true, false); 1033 1034 ovs_kfree_skb_reason(skb, OVS_DROP_IP_TTL); 1035 return 0; 1036 } 1037 1038 /* When 'last' is true, sample() should always consume the 'skb'. 1039 * Otherwise, sample() should keep 'skb' intact regardless what 1040 * actions are executed within sample(). 1041 */ 1042 static int sample(struct datapath *dp, struct sk_buff *skb, 1043 struct sw_flow_key *key, const struct nlattr *attr, 1044 bool last) 1045 { 1046 struct nlattr *actions; 1047 struct nlattr *sample_arg; 1048 int rem = nla_len(attr); 1049 const struct sample_arg *arg; 1050 u32 init_probability; 1051 bool clone_flow_key; 1052 int err; 1053 1054 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ 1055 sample_arg = nla_data(attr); 1056 arg = nla_data(sample_arg); 1057 actions = nla_next(sample_arg, &rem); 1058 init_probability = OVS_CB(skb)->probability; 1059 1060 if ((arg->probability != U32_MAX) && 1061 (!arg->probability || get_random_u32() > arg->probability)) { 1062 if (last) 1063 ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); 1064 return 0; 1065 } 1066 1067 OVS_CB(skb)->probability = arg->probability; 1068 1069 clone_flow_key = !arg->exec; 1070 err = clone_execute(dp, skb, key, 0, actions, rem, last, 1071 clone_flow_key); 1072 1073 if (!last) 1074 OVS_CB(skb)->probability = init_probability; 1075 1076 return err; 1077 } 1078 1079 /* When 'last' is true, clone() should always consume the 'skb'. 1080 * Otherwise, clone() should keep 'skb' intact regardless what 1081 * actions are executed within clone(). 1082 */ 1083 static int clone(struct datapath *dp, struct sk_buff *skb, 1084 struct sw_flow_key *key, const struct nlattr *attr, 1085 bool last) 1086 { 1087 struct nlattr *actions; 1088 struct nlattr *clone_arg; 1089 int rem = nla_len(attr); 1090 bool dont_clone_flow_key; 1091 1092 /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */ 1093 clone_arg = nla_data(attr); 1094 dont_clone_flow_key = nla_get_u32(clone_arg); 1095 actions = nla_next(clone_arg, &rem); 1096 1097 return clone_execute(dp, skb, key, 0, actions, rem, last, 1098 !dont_clone_flow_key); 1099 } 1100 1101 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 1102 const struct nlattr *attr) 1103 { 1104 struct ovs_action_hash *hash_act = nla_data(attr); 1105 u32 hash = 0; 1106 1107 if (hash_act->hash_alg == OVS_HASH_ALG_L4) { 1108 /* OVS_HASH_ALG_L4 hasing type. */ 1109 hash = skb_get_hash(skb); 1110 } else if (hash_act->hash_alg == OVS_HASH_ALG_SYM_L4) { 1111 /* OVS_HASH_ALG_SYM_L4 hashing type. NOTE: this doesn't 1112 * extend past an encapsulated header. 1113 */ 1114 hash = __skb_get_hash_symmetric(skb); 1115 } 1116 1117 hash = jhash_1word(hash, hash_act->hash_basis); 1118 if (!hash) 1119 hash = 0x1; 1120 1121 key->ovs_flow_hash = hash; 1122 } 1123 1124 static int execute_set_action(struct sk_buff *skb, 1125 struct sw_flow_key *flow_key, 1126 const struct nlattr *a) 1127 { 1128 /* Only tunnel set execution is supported without a mask. */ 1129 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1130 struct ovs_tunnel_info *tun = nla_data(a); 1131 1132 skb_dst_drop(skb); 1133 dst_hold((struct dst_entry *)tun->tun_dst); 1134 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 1135 return 0; 1136 } 1137 1138 return -EINVAL; 1139 } 1140 1141 /* Mask is at the midpoint of the data. */ 1142 #define get_mask(a, type) ((const type)nla_data(a) + 1) 1143 1144 static int execute_masked_set_action(struct sk_buff *skb, 1145 struct sw_flow_key *flow_key, 1146 const struct nlattr *a) 1147 { 1148 int err = 0; 1149 1150 switch (nla_type(a)) { 1151 case OVS_KEY_ATTR_PRIORITY: 1152 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 1153 *get_mask(a, u32 *)); 1154 flow_key->phy.priority = skb->priority; 1155 break; 1156 1157 case OVS_KEY_ATTR_SKB_MARK: 1158 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 1159 flow_key->phy.skb_mark = skb->mark; 1160 break; 1161 1162 case OVS_KEY_ATTR_TUNNEL_INFO: 1163 /* Masked data not supported for tunnel. */ 1164 err = -EINVAL; 1165 break; 1166 1167 case OVS_KEY_ATTR_ETHERNET: 1168 err = set_eth_addr(skb, flow_key, nla_data(a), 1169 get_mask(a, struct ovs_key_ethernet *)); 1170 break; 1171 1172 case OVS_KEY_ATTR_NSH: 1173 err = set_nsh(skb, flow_key, a); 1174 break; 1175 1176 case OVS_KEY_ATTR_IPV4: 1177 err = set_ipv4(skb, flow_key, nla_data(a), 1178 get_mask(a, struct ovs_key_ipv4 *)); 1179 break; 1180 1181 case OVS_KEY_ATTR_IPV6: 1182 err = set_ipv6(skb, flow_key, nla_data(a), 1183 get_mask(a, struct ovs_key_ipv6 *)); 1184 break; 1185 1186 case OVS_KEY_ATTR_TCP: 1187 err = set_tcp(skb, flow_key, nla_data(a), 1188 get_mask(a, struct ovs_key_tcp *)); 1189 break; 1190 1191 case OVS_KEY_ATTR_UDP: 1192 err = set_udp(skb, flow_key, nla_data(a), 1193 get_mask(a, struct ovs_key_udp *)); 1194 break; 1195 1196 case OVS_KEY_ATTR_SCTP: 1197 err = set_sctp(skb, flow_key, nla_data(a), 1198 get_mask(a, struct ovs_key_sctp *)); 1199 break; 1200 1201 case OVS_KEY_ATTR_MPLS: 1202 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1203 __be32 *)); 1204 break; 1205 1206 case OVS_KEY_ATTR_CT_STATE: 1207 case OVS_KEY_ATTR_CT_ZONE: 1208 case OVS_KEY_ATTR_CT_MARK: 1209 case OVS_KEY_ATTR_CT_LABELS: 1210 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: 1211 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: 1212 err = -EINVAL; 1213 break; 1214 } 1215 1216 return err; 1217 } 1218 1219 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1220 struct sw_flow_key *key, 1221 const struct nlattr *a, bool last) 1222 { 1223 u32 recirc_id; 1224 1225 if (!is_flow_key_valid(key)) { 1226 int err; 1227 1228 err = ovs_flow_key_update(skb, key); 1229 if (err) 1230 return err; 1231 } 1232 BUG_ON(!is_flow_key_valid(key)); 1233 1234 recirc_id = nla_get_u32(a); 1235 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); 1236 } 1237 1238 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb, 1239 struct sw_flow_key *key, 1240 const struct nlattr *attr, bool last) 1241 { 1242 struct ovs_skb_cb *ovs_cb = OVS_CB(skb); 1243 const struct nlattr *actions, *cpl_arg; 1244 int len, max_len, rem = nla_len(attr); 1245 const struct check_pkt_len_arg *arg; 1246 bool clone_flow_key; 1247 1248 /* The first netlink attribute in 'attr' is always 1249 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'. 1250 */ 1251 cpl_arg = nla_data(attr); 1252 arg = nla_data(cpl_arg); 1253 1254 len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len; 1255 max_len = arg->pkt_len; 1256 1257 if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) || 1258 len <= max_len) { 1259 /* Second netlink attribute in 'attr' is always 1260 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'. 1261 */ 1262 actions = nla_next(cpl_arg, &rem); 1263 clone_flow_key = !arg->exec_for_lesser_equal; 1264 } else { 1265 /* Third netlink attribute in 'attr' is always 1266 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'. 1267 */ 1268 actions = nla_next(cpl_arg, &rem); 1269 actions = nla_next(actions, &rem); 1270 clone_flow_key = !arg->exec_for_greater; 1271 } 1272 1273 return clone_execute(dp, skb, key, 0, nla_data(actions), 1274 nla_len(actions), last, clone_flow_key); 1275 } 1276 1277 static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) 1278 { 1279 int err; 1280 1281 if (skb->protocol == htons(ETH_P_IPV6)) { 1282 struct ipv6hdr *nh; 1283 1284 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1285 sizeof(*nh)); 1286 if (unlikely(err)) 1287 return err; 1288 1289 nh = ipv6_hdr(skb); 1290 1291 if (nh->hop_limit <= 1) 1292 return -EHOSTUNREACH; 1293 1294 key->ip.ttl = --nh->hop_limit; 1295 } else if (skb->protocol == htons(ETH_P_IP)) { 1296 struct iphdr *nh; 1297 u8 old_ttl; 1298 1299 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1300 sizeof(*nh)); 1301 if (unlikely(err)) 1302 return err; 1303 1304 nh = ip_hdr(skb); 1305 if (nh->ttl <= 1) 1306 return -EHOSTUNREACH; 1307 1308 old_ttl = nh->ttl--; 1309 csum_replace2(&nh->check, htons(old_ttl << 8), 1310 htons(nh->ttl << 8)); 1311 key->ip.ttl = nh->ttl; 1312 } 1313 return 0; 1314 } 1315 1316 #if IS_ENABLED(CONFIG_PSAMPLE) 1317 static void execute_psample(struct datapath *dp, struct sk_buff *skb, 1318 const struct nlattr *attr) 1319 { 1320 struct psample_group psample_group = {}; 1321 struct psample_metadata md = {}; 1322 const struct nlattr *a; 1323 u32 rate; 1324 int rem; 1325 1326 nla_for_each_attr(a, nla_data(attr), nla_len(attr), rem) { 1327 switch (nla_type(a)) { 1328 case OVS_PSAMPLE_ATTR_GROUP: 1329 psample_group.group_num = nla_get_u32(a); 1330 break; 1331 1332 case OVS_PSAMPLE_ATTR_COOKIE: 1333 md.user_cookie = nla_data(a); 1334 md.user_cookie_len = nla_len(a); 1335 break; 1336 } 1337 } 1338 1339 psample_group.net = ovs_dp_get_net(dp); 1340 md.in_ifindex = OVS_CB(skb)->input_vport->dev->ifindex; 1341 md.trunc_size = skb->len - OVS_CB(skb)->cutlen; 1342 md.rate_as_probability = 1; 1343 1344 rate = OVS_CB(skb)->probability ? OVS_CB(skb)->probability : U32_MAX; 1345 1346 psample_sample_packet(&psample_group, skb, rate, &md); 1347 } 1348 #else 1349 static void execute_psample(struct datapath *dp, struct sk_buff *skb, 1350 const struct nlattr *attr) 1351 {} 1352 #endif 1353 1354 /* Execute a list of actions against 'skb'. */ 1355 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1356 struct sw_flow_key *key, 1357 const struct nlattr *attr, int len) 1358 { 1359 const struct nlattr *a; 1360 int rem; 1361 1362 for (a = attr, rem = len; rem > 0; 1363 a = nla_next(a, &rem)) { 1364 int err = 0; 1365 1366 if (trace_ovs_do_execute_action_enabled()) 1367 trace_ovs_do_execute_action(dp, skb, key, a, rem); 1368 1369 /* Actions that rightfully have to consume the skb should do it 1370 * and return directly. 1371 */ 1372 switch (nla_type(a)) { 1373 case OVS_ACTION_ATTR_OUTPUT: { 1374 int port = nla_get_u32(a); 1375 struct sk_buff *clone; 1376 1377 /* Every output action needs a separate clone 1378 * of 'skb', In case the output action is the 1379 * last action, cloning can be avoided. 1380 */ 1381 if (nla_is_last(a, rem)) { 1382 do_output(dp, skb, port, key); 1383 /* 'skb' has been used for output. 1384 */ 1385 return 0; 1386 } 1387 1388 clone = skb_clone(skb, GFP_ATOMIC); 1389 if (clone) 1390 do_output(dp, clone, port, key); 1391 OVS_CB(skb)->cutlen = 0; 1392 break; 1393 } 1394 1395 case OVS_ACTION_ATTR_TRUNC: { 1396 struct ovs_action_trunc *trunc = nla_data(a); 1397 1398 if (skb->len > trunc->max_len) 1399 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1400 break; 1401 } 1402 1403 case OVS_ACTION_ATTR_USERSPACE: 1404 output_userspace(dp, skb, key, a, attr, 1405 len, OVS_CB(skb)->cutlen); 1406 OVS_CB(skb)->cutlen = 0; 1407 if (nla_is_last(a, rem)) { 1408 consume_skb(skb); 1409 return 0; 1410 } 1411 break; 1412 1413 case OVS_ACTION_ATTR_HASH: 1414 execute_hash(skb, key, a); 1415 break; 1416 1417 case OVS_ACTION_ATTR_PUSH_MPLS: { 1418 struct ovs_action_push_mpls *mpls = nla_data(a); 1419 1420 err = push_mpls(skb, key, mpls->mpls_lse, 1421 mpls->mpls_ethertype, skb->mac_len); 1422 break; 1423 } 1424 case OVS_ACTION_ATTR_ADD_MPLS: { 1425 struct ovs_action_add_mpls *mpls = nla_data(a); 1426 __u16 mac_len = 0; 1427 1428 if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK) 1429 mac_len = skb->mac_len; 1430 1431 err = push_mpls(skb, key, mpls->mpls_lse, 1432 mpls->mpls_ethertype, mac_len); 1433 break; 1434 } 1435 case OVS_ACTION_ATTR_POP_MPLS: 1436 err = pop_mpls(skb, key, nla_get_be16(a)); 1437 break; 1438 1439 case OVS_ACTION_ATTR_PUSH_VLAN: 1440 err = push_vlan(skb, key, nla_data(a)); 1441 break; 1442 1443 case OVS_ACTION_ATTR_POP_VLAN: 1444 err = pop_vlan(skb, key); 1445 break; 1446 1447 case OVS_ACTION_ATTR_RECIRC: { 1448 bool last = nla_is_last(a, rem); 1449 1450 err = execute_recirc(dp, skb, key, a, last); 1451 if (last) { 1452 /* If this is the last action, the skb has 1453 * been consumed or freed. 1454 * Return immediately. 1455 */ 1456 return err; 1457 } 1458 break; 1459 } 1460 1461 case OVS_ACTION_ATTR_SET: 1462 err = execute_set_action(skb, key, nla_data(a)); 1463 break; 1464 1465 case OVS_ACTION_ATTR_SET_MASKED: 1466 case OVS_ACTION_ATTR_SET_TO_MASKED: 1467 err = execute_masked_set_action(skb, key, nla_data(a)); 1468 break; 1469 1470 case OVS_ACTION_ATTR_SAMPLE: { 1471 bool last = nla_is_last(a, rem); 1472 1473 err = sample(dp, skb, key, a, last); 1474 if (last) 1475 return err; 1476 1477 break; 1478 } 1479 1480 case OVS_ACTION_ATTR_CT: 1481 if (!is_flow_key_valid(key)) { 1482 err = ovs_flow_key_update(skb, key); 1483 if (err) 1484 return err; 1485 } 1486 1487 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1488 nla_data(a)); 1489 1490 /* Hide stolen IP fragments from user space. */ 1491 if (err) 1492 return err == -EINPROGRESS ? 0 : err; 1493 break; 1494 1495 case OVS_ACTION_ATTR_CT_CLEAR: 1496 err = ovs_ct_clear(skb, key); 1497 break; 1498 1499 case OVS_ACTION_ATTR_PUSH_ETH: 1500 err = push_eth(skb, key, nla_data(a)); 1501 break; 1502 1503 case OVS_ACTION_ATTR_POP_ETH: 1504 err = pop_eth(skb, key); 1505 break; 1506 1507 case OVS_ACTION_ATTR_PUSH_NSH: 1508 err = push_nsh(skb, key, nla_data(a)); 1509 break; 1510 1511 case OVS_ACTION_ATTR_POP_NSH: 1512 err = pop_nsh(skb, key); 1513 break; 1514 1515 case OVS_ACTION_ATTR_METER: 1516 if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { 1517 ovs_kfree_skb_reason(skb, OVS_DROP_METER); 1518 return 0; 1519 } 1520 break; 1521 1522 case OVS_ACTION_ATTR_CLONE: { 1523 bool last = nla_is_last(a, rem); 1524 1525 err = clone(dp, skb, key, a, last); 1526 if (last) 1527 return err; 1528 1529 break; 1530 } 1531 1532 case OVS_ACTION_ATTR_CHECK_PKT_LEN: { 1533 bool last = nla_is_last(a, rem); 1534 1535 err = execute_check_pkt_len(dp, skb, key, a, last); 1536 if (last) 1537 return err; 1538 1539 break; 1540 } 1541 1542 case OVS_ACTION_ATTR_DEC_TTL: 1543 err = execute_dec_ttl(skb, key); 1544 if (err == -EHOSTUNREACH) 1545 return dec_ttl_exception_handler(dp, skb, 1546 key, a); 1547 break; 1548 1549 case OVS_ACTION_ATTR_DROP: { 1550 enum ovs_drop_reason reason = nla_get_u32(a) 1551 ? OVS_DROP_EXPLICIT_WITH_ERROR 1552 : OVS_DROP_EXPLICIT; 1553 1554 ovs_kfree_skb_reason(skb, reason); 1555 return 0; 1556 } 1557 1558 case OVS_ACTION_ATTR_PSAMPLE: 1559 execute_psample(dp, skb, a); 1560 OVS_CB(skb)->cutlen = 0; 1561 if (nla_is_last(a, rem)) { 1562 consume_skb(skb); 1563 return 0; 1564 } 1565 break; 1566 } 1567 1568 if (unlikely(err)) { 1569 ovs_kfree_skb_reason(skb, OVS_DROP_ACTION_ERROR); 1570 return err; 1571 } 1572 } 1573 1574 ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); 1575 return 0; 1576 } 1577 1578 /* Execute the actions on the clone of the packet. The effect of the 1579 * execution does not affect the original 'skb' nor the original 'key'. 1580 * 1581 * The execution may be deferred in case the actions can not be executed 1582 * immediately. 1583 */ 1584 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 1585 struct sw_flow_key *key, u32 recirc_id, 1586 const struct nlattr *actions, int len, 1587 bool last, bool clone_flow_key) 1588 { 1589 struct deferred_action *da; 1590 struct sw_flow_key *clone; 1591 1592 skb = last ? skb : skb_clone(skb, GFP_ATOMIC); 1593 if (!skb) { 1594 /* Out of memory, skip this action. 1595 */ 1596 return 0; 1597 } 1598 1599 /* When clone_flow_key is false, the 'key' will not be change 1600 * by the actions, then the 'key' can be used directly. 1601 * Otherwise, try to clone key from the next recursion level of 1602 * 'flow_keys'. If clone is successful, execute the actions 1603 * without deferring. 1604 */ 1605 clone = clone_flow_key ? clone_key(key) : key; 1606 if (clone) { 1607 int err = 0; 1608 1609 if (actions) { /* Sample action */ 1610 if (clone_flow_key) 1611 __this_cpu_inc(exec_actions_level); 1612 1613 err = do_execute_actions(dp, skb, clone, 1614 actions, len); 1615 1616 if (clone_flow_key) 1617 __this_cpu_dec(exec_actions_level); 1618 } else { /* Recirc action */ 1619 clone->recirc_id = recirc_id; 1620 ovs_dp_process_packet(skb, clone); 1621 } 1622 return err; 1623 } 1624 1625 /* Out of 'flow_keys' space. Defer actions */ 1626 da = add_deferred_actions(skb, key, actions, len); 1627 if (da) { 1628 if (!actions) { /* Recirc action */ 1629 key = &da->pkt_key; 1630 key->recirc_id = recirc_id; 1631 } 1632 } else { 1633 /* Out of per CPU action FIFO space. Drop the 'skb' and 1634 * log an error. 1635 */ 1636 ovs_kfree_skb_reason(skb, OVS_DROP_DEFERRED_LIMIT); 1637 1638 if (net_ratelimit()) { 1639 if (actions) { /* Sample action */ 1640 pr_warn("%s: deferred action limit reached, drop sample action\n", 1641 ovs_dp_name(dp)); 1642 } else { /* Recirc action */ 1643 pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n", 1644 ovs_dp_name(dp), recirc_id); 1645 } 1646 } 1647 } 1648 return 0; 1649 } 1650 1651 static void process_deferred_actions(struct datapath *dp) 1652 { 1653 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1654 1655 /* Do not touch the FIFO in case there is no deferred actions. */ 1656 if (action_fifo_is_empty(fifo)) 1657 return; 1658 1659 /* Finishing executing all deferred actions. */ 1660 do { 1661 struct deferred_action *da = action_fifo_get(fifo); 1662 struct sk_buff *skb = da->skb; 1663 struct sw_flow_key *key = &da->pkt_key; 1664 const struct nlattr *actions = da->actions; 1665 int actions_len = da->actions_len; 1666 1667 if (actions) 1668 do_execute_actions(dp, skb, key, actions, actions_len); 1669 else 1670 ovs_dp_process_packet(skb, key); 1671 } while (!action_fifo_is_empty(fifo)); 1672 1673 /* Reset FIFO for the next packet. */ 1674 action_fifo_init(fifo); 1675 } 1676 1677 /* Execute a list of actions against 'skb'. */ 1678 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1679 const struct sw_flow_actions *acts, 1680 struct sw_flow_key *key) 1681 { 1682 int err, level; 1683 1684 level = __this_cpu_inc_return(exec_actions_level); 1685 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1686 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1687 ovs_dp_name(dp)); 1688 ovs_kfree_skb_reason(skb, OVS_DROP_RECURSION_LIMIT); 1689 err = -ENETDOWN; 1690 goto out; 1691 } 1692 1693 OVS_CB(skb)->acts_origlen = acts->orig_len; 1694 err = do_execute_actions(dp, skb, key, 1695 acts->actions, acts->actions_len); 1696 1697 if (level == 1) 1698 process_deferred_actions(dp); 1699 1700 out: 1701 __this_cpu_dec(exec_actions_level); 1702 return err; 1703 } 1704 1705 int action_fifos_init(void) 1706 { 1707 action_fifos = alloc_percpu(struct action_fifo); 1708 if (!action_fifos) 1709 return -ENOMEM; 1710 1711 flow_keys = alloc_percpu(struct action_flow_keys); 1712 if (!flow_keys) { 1713 free_percpu(action_fifos); 1714 return -ENOMEM; 1715 } 1716 1717 return 0; 1718 } 1719 1720 void action_fifos_exit(void) 1721 { 1722 free_percpu(action_fifos); 1723 free_percpu(flow_keys); 1724 } 1725