1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2007-2014 Nicira, Inc. 4 */ 5 6 #include <linux/uaccess.h> 7 #include <linux/netdevice.h> 8 #include <linux/etherdevice.h> 9 #include <linux/if_ether.h> 10 #include <linux/if_vlan.h> 11 #include <net/llc_pdu.h> 12 #include <linux/kernel.h> 13 #include <linux/jhash.h> 14 #include <linux/jiffies.h> 15 #include <linux/llc.h> 16 #include <linux/module.h> 17 #include <linux/in.h> 18 #include <linux/rcupdate.h> 19 #include <linux/cpumask.h> 20 #include <linux/if_arp.h> 21 #include <linux/ip.h> 22 #include <linux/ipv6.h> 23 #include <linux/mpls.h> 24 #include <linux/sctp.h> 25 #include <linux/smp.h> 26 #include <linux/tcp.h> 27 #include <linux/udp.h> 28 #include <linux/icmp.h> 29 #include <linux/icmpv6.h> 30 #include <linux/rculist.h> 31 #include <net/ip.h> 32 #include <net/ip_tunnels.h> 33 #include <net/ipv6.h> 34 #include <net/mpls.h> 35 #include <net/ndisc.h> 36 #include <net/nsh.h> 37 #include <net/pkt_cls.h> 38 #include <net/netfilter/nf_conntrack_zones.h> 39 40 #include "conntrack.h" 41 #include "datapath.h" 42 #include "flow.h" 43 #include "flow_netlink.h" 44 #include "vport.h" 45 46 u64 ovs_flow_used_time(unsigned long flow_jiffies) 47 { 48 struct timespec64 cur_ts; 49 u64 cur_ms, idle_ms; 50 51 ktime_get_ts64(&cur_ts); 52 idle_ms = jiffies_to_msecs(jiffies - flow_jiffies); 53 cur_ms = (u64)(u32)cur_ts.tv_sec * MSEC_PER_SEC + 54 cur_ts.tv_nsec / NSEC_PER_MSEC; 55 56 return cur_ms - idle_ms; 57 } 58 59 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF)) 60 61 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags, 62 const struct sk_buff *skb) 63 { 64 struct sw_flow_stats *stats; 65 unsigned int cpu = smp_processor_id(); 66 int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0); 67 68 stats = rcu_dereference(flow->stats[cpu]); 69 70 /* Check if already have CPU-specific stats. */ 71 if (likely(stats)) { 72 spin_lock(&stats->lock); 73 /* Mark if we write on the pre-allocated stats. */ 74 if (cpu == 0 && unlikely(flow->stats_last_writer != cpu)) 75 flow->stats_last_writer = cpu; 76 } else { 77 stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */ 78 spin_lock(&stats->lock); 79 80 /* If the current CPU is the only writer on the 81 * pre-allocated stats keep using them. 82 */ 83 if (unlikely(flow->stats_last_writer != cpu)) { 84 /* A previous locker may have already allocated the 85 * stats, so we need to check again. If CPU-specific 86 * stats were already allocated, we update the pre- 87 * allocated stats as we have already locked them. 88 */ 89 if (likely(flow->stats_last_writer != -1) && 90 likely(!rcu_access_pointer(flow->stats[cpu]))) { 91 /* Try to allocate CPU-specific stats. */ 92 struct sw_flow_stats *new_stats; 93 94 new_stats = 95 kmem_cache_alloc_node(flow_stats_cache, 96 GFP_NOWAIT | 97 __GFP_THISNODE | 98 __GFP_NOWARN | 99 __GFP_NOMEMALLOC, 100 numa_node_id()); 101 if (likely(new_stats)) { 102 new_stats->used = jiffies; 103 new_stats->packet_count = 1; 104 new_stats->byte_count = len; 105 new_stats->tcp_flags = tcp_flags; 106 spin_lock_init(&new_stats->lock); 107 108 rcu_assign_pointer(flow->stats[cpu], 109 new_stats); 110 cpumask_set_cpu(cpu, 111 flow->cpu_used_mask); 112 goto unlock; 113 } 114 } 115 flow->stats_last_writer = cpu; 116 } 117 } 118 119 stats->used = jiffies; 120 stats->packet_count++; 121 stats->byte_count += len; 122 stats->tcp_flags |= tcp_flags; 123 unlock: 124 spin_unlock(&stats->lock); 125 } 126 127 /* Must be called with rcu_read_lock or ovs_mutex. */ 128 void ovs_flow_stats_get(const struct sw_flow *flow, 129 struct ovs_flow_stats *ovs_stats, 130 unsigned long *used, __be16 *tcp_flags) 131 { 132 int cpu; 133 134 *used = 0; 135 *tcp_flags = 0; 136 memset(ovs_stats, 0, sizeof(*ovs_stats)); 137 138 /* We open code this to make sure cpu 0 is always considered */ 139 for (cpu = 0; cpu < nr_cpu_ids; 140 cpu = cpumask_next(cpu, flow->cpu_used_mask)) { 141 struct sw_flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]); 142 143 if (stats) { 144 /* Local CPU may write on non-local stats, so we must 145 * block bottom-halves here. 146 */ 147 spin_lock_bh(&stats->lock); 148 if (!*used || time_after(stats->used, *used)) 149 *used = stats->used; 150 *tcp_flags |= stats->tcp_flags; 151 ovs_stats->n_packets += stats->packet_count; 152 ovs_stats->n_bytes += stats->byte_count; 153 spin_unlock_bh(&stats->lock); 154 } 155 } 156 } 157 158 /* Called with ovs_mutex. */ 159 void ovs_flow_stats_clear(struct sw_flow *flow) 160 { 161 int cpu; 162 163 /* We open code this to make sure cpu 0 is always considered */ 164 for (cpu = 0; cpu < nr_cpu_ids; 165 cpu = cpumask_next(cpu, flow->cpu_used_mask)) { 166 struct sw_flow_stats *stats = ovsl_dereference(flow->stats[cpu]); 167 168 if (stats) { 169 spin_lock_bh(&stats->lock); 170 stats->used = 0; 171 stats->packet_count = 0; 172 stats->byte_count = 0; 173 stats->tcp_flags = 0; 174 spin_unlock_bh(&stats->lock); 175 } 176 } 177 } 178 179 static int check_header(struct sk_buff *skb, int len) 180 { 181 if (unlikely(skb->len < len)) 182 return -EINVAL; 183 if (unlikely(!pskb_may_pull(skb, len))) 184 return -ENOMEM; 185 return 0; 186 } 187 188 static bool arphdr_ok(struct sk_buff *skb) 189 { 190 return pskb_may_pull(skb, skb_network_offset(skb) + 191 sizeof(struct arp_eth_header)); 192 } 193 194 static int check_iphdr(struct sk_buff *skb) 195 { 196 unsigned int nh_ofs = skb_network_offset(skb); 197 unsigned int ip_len; 198 int err; 199 200 err = check_header(skb, nh_ofs + sizeof(struct iphdr)); 201 if (unlikely(err)) 202 return err; 203 204 ip_len = ip_hdrlen(skb); 205 if (unlikely(ip_len < sizeof(struct iphdr) || 206 skb->len < nh_ofs + ip_len)) 207 return -EINVAL; 208 209 skb_set_transport_header(skb, nh_ofs + ip_len); 210 return 0; 211 } 212 213 static bool tcphdr_ok(struct sk_buff *skb) 214 { 215 int th_ofs = skb_transport_offset(skb); 216 int tcp_len; 217 218 if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr)))) 219 return false; 220 221 tcp_len = tcp_hdrlen(skb); 222 if (unlikely(tcp_len < sizeof(struct tcphdr) || 223 skb->len < th_ofs + tcp_len)) 224 return false; 225 226 return true; 227 } 228 229 static bool udphdr_ok(struct sk_buff *skb) 230 { 231 return pskb_may_pull(skb, skb_transport_offset(skb) + 232 sizeof(struct udphdr)); 233 } 234 235 static bool sctphdr_ok(struct sk_buff *skb) 236 { 237 return pskb_may_pull(skb, skb_transport_offset(skb) + 238 sizeof(struct sctphdr)); 239 } 240 241 static bool icmphdr_ok(struct sk_buff *skb) 242 { 243 return pskb_may_pull(skb, skb_transport_offset(skb) + 244 sizeof(struct icmphdr)); 245 } 246 247 /** 248 * get_ipv6_ext_hdrs() - Parses packet and sets IPv6 extension header flags. 249 * 250 * @skb: buffer where extension header data starts in packet 251 * @nh: ipv6 header 252 * @ext_hdrs: flags are stored here 253 * 254 * OFPIEH12_UNREP is set if more than one of a given IPv6 extension header 255 * is unexpectedly encountered. (Two destination options headers may be 256 * expected and would not cause this bit to be set.) 257 * 258 * OFPIEH12_UNSEQ is set if IPv6 extension headers were not in the order 259 * preferred (but not required) by RFC 2460: 260 * 261 * When more than one extension header is used in the same packet, it is 262 * recommended that those headers appear in the following order: 263 * IPv6 header 264 * Hop-by-Hop Options header 265 * Destination Options header 266 * Routing header 267 * Fragment header 268 * Authentication header 269 * Encapsulating Security Payload header 270 * Destination Options header 271 * upper-layer header 272 */ 273 static void get_ipv6_ext_hdrs(struct sk_buff *skb, struct ipv6hdr *nh, 274 u16 *ext_hdrs) 275 { 276 u8 next_type = nh->nexthdr; 277 unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr); 278 int dest_options_header_count = 0; 279 280 *ext_hdrs = 0; 281 282 while (ipv6_ext_hdr(next_type)) { 283 struct ipv6_opt_hdr _hdr, *hp; 284 285 switch (next_type) { 286 case IPPROTO_NONE: 287 *ext_hdrs |= OFPIEH12_NONEXT; 288 /* stop parsing */ 289 return; 290 291 case IPPROTO_ESP: 292 if (*ext_hdrs & OFPIEH12_ESP) 293 *ext_hdrs |= OFPIEH12_UNREP; 294 if ((*ext_hdrs & ~(OFPIEH12_HOP | OFPIEH12_DEST | 295 OFPIEH12_ROUTER | IPPROTO_FRAGMENT | 296 OFPIEH12_AUTH | OFPIEH12_UNREP)) || 297 dest_options_header_count >= 2) { 298 *ext_hdrs |= OFPIEH12_UNSEQ; 299 } 300 *ext_hdrs |= OFPIEH12_ESP; 301 break; 302 303 case IPPROTO_AH: 304 if (*ext_hdrs & OFPIEH12_AUTH) 305 *ext_hdrs |= OFPIEH12_UNREP; 306 if ((*ext_hdrs & 307 ~(OFPIEH12_HOP | OFPIEH12_DEST | OFPIEH12_ROUTER | 308 IPPROTO_FRAGMENT | OFPIEH12_UNREP)) || 309 dest_options_header_count >= 2) { 310 *ext_hdrs |= OFPIEH12_UNSEQ; 311 } 312 *ext_hdrs |= OFPIEH12_AUTH; 313 break; 314 315 case IPPROTO_DSTOPTS: 316 if (dest_options_header_count == 0) { 317 if (*ext_hdrs & 318 ~(OFPIEH12_HOP | OFPIEH12_UNREP)) 319 *ext_hdrs |= OFPIEH12_UNSEQ; 320 *ext_hdrs |= OFPIEH12_DEST; 321 } else if (dest_options_header_count == 1) { 322 if (*ext_hdrs & 323 ~(OFPIEH12_HOP | OFPIEH12_DEST | 324 OFPIEH12_ROUTER | OFPIEH12_FRAG | 325 OFPIEH12_AUTH | OFPIEH12_ESP | 326 OFPIEH12_UNREP)) { 327 *ext_hdrs |= OFPIEH12_UNSEQ; 328 } 329 } else { 330 *ext_hdrs |= OFPIEH12_UNREP; 331 } 332 dest_options_header_count++; 333 break; 334 335 case IPPROTO_FRAGMENT: 336 if (*ext_hdrs & OFPIEH12_FRAG) 337 *ext_hdrs |= OFPIEH12_UNREP; 338 if ((*ext_hdrs & ~(OFPIEH12_HOP | 339 OFPIEH12_DEST | 340 OFPIEH12_ROUTER | 341 OFPIEH12_UNREP)) || 342 dest_options_header_count >= 2) { 343 *ext_hdrs |= OFPIEH12_UNSEQ; 344 } 345 *ext_hdrs |= OFPIEH12_FRAG; 346 break; 347 348 case IPPROTO_ROUTING: 349 if (*ext_hdrs & OFPIEH12_ROUTER) 350 *ext_hdrs |= OFPIEH12_UNREP; 351 if ((*ext_hdrs & ~(OFPIEH12_HOP | 352 OFPIEH12_DEST | 353 OFPIEH12_UNREP)) || 354 dest_options_header_count >= 2) { 355 *ext_hdrs |= OFPIEH12_UNSEQ; 356 } 357 *ext_hdrs |= OFPIEH12_ROUTER; 358 break; 359 360 case IPPROTO_HOPOPTS: 361 if (*ext_hdrs & OFPIEH12_HOP) 362 *ext_hdrs |= OFPIEH12_UNREP; 363 /* OFPIEH12_HOP is set to 1 if a hop-by-hop IPv6 364 * extension header is present as the first 365 * extension header in the packet. 366 */ 367 if (*ext_hdrs == 0) 368 *ext_hdrs |= OFPIEH12_HOP; 369 else 370 *ext_hdrs |= OFPIEH12_UNSEQ; 371 break; 372 373 default: 374 return; 375 } 376 377 hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr); 378 if (!hp) 379 break; 380 next_type = hp->nexthdr; 381 start += ipv6_optlen(hp); 382 } 383 } 384 385 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key) 386 { 387 unsigned short frag_off; 388 unsigned int payload_ofs = 0; 389 unsigned int nh_ofs = skb_network_offset(skb); 390 unsigned int nh_len; 391 struct ipv6hdr *nh; 392 int err, nexthdr, flags = 0; 393 394 err = check_header(skb, nh_ofs + sizeof(*nh)); 395 if (unlikely(err)) 396 return err; 397 398 nh = ipv6_hdr(skb); 399 400 get_ipv6_ext_hdrs(skb, nh, &key->ipv6.exthdrs); 401 402 key->ip.proto = NEXTHDR_NONE; 403 key->ip.tos = ipv6_get_dsfield(nh); 404 key->ip.ttl = nh->hop_limit; 405 key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 406 key->ipv6.addr.src = nh->saddr; 407 key->ipv6.addr.dst = nh->daddr; 408 409 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 410 if (flags & IP6_FH_F_FRAG) { 411 if (frag_off) { 412 key->ip.frag = OVS_FRAG_TYPE_LATER; 413 key->ip.proto = NEXTHDR_FRAGMENT; 414 return 0; 415 } 416 key->ip.frag = OVS_FRAG_TYPE_FIRST; 417 } else { 418 key->ip.frag = OVS_FRAG_TYPE_NONE; 419 } 420 421 /* Delayed handling of error in ipv6_find_hdr() as it 422 * always sets flags and frag_off to a valid value which may be 423 * used to set key->ip.frag above. 424 */ 425 if (unlikely(nexthdr < 0)) 426 return -EPROTO; 427 428 nh_len = payload_ofs - nh_ofs; 429 skb_set_transport_header(skb, nh_ofs + nh_len); 430 key->ip.proto = nexthdr; 431 return nh_len; 432 } 433 434 static bool icmp6hdr_ok(struct sk_buff *skb) 435 { 436 return pskb_may_pull(skb, skb_transport_offset(skb) + 437 sizeof(struct icmp6hdr)); 438 } 439 440 /** 441 * parse_vlan_tag - Parse vlan tag from vlan header. 442 * @skb: skb containing frame to parse 443 * @key_vh: pointer to parsed vlan tag 444 * @untag_vlan: should the vlan header be removed from the frame 445 * 446 * Return: ERROR on memory error. 447 * %0 if it encounters a non-vlan or incomplete packet. 448 * %1 after successfully parsing vlan tag. 449 */ 450 static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh, 451 bool untag_vlan) 452 { 453 struct vlan_head *vh = (struct vlan_head *)skb->data; 454 455 if (likely(!eth_type_vlan(vh->tpid))) 456 return 0; 457 458 if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16))) 459 return 0; 460 461 if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) + 462 sizeof(__be16)))) 463 return -ENOMEM; 464 465 vh = (struct vlan_head *)skb->data; 466 key_vh->tci = vh->tci | htons(VLAN_CFI_MASK); 467 key_vh->tpid = vh->tpid; 468 469 if (unlikely(untag_vlan)) { 470 int offset = skb->data - skb_mac_header(skb); 471 u16 tci; 472 int err; 473 474 __skb_push(skb, offset); 475 err = __skb_vlan_pop(skb, &tci); 476 __skb_pull(skb, offset); 477 if (err) 478 return err; 479 __vlan_hwaccel_put_tag(skb, key_vh->tpid, tci); 480 } else { 481 __skb_pull(skb, sizeof(struct vlan_head)); 482 } 483 return 1; 484 } 485 486 static void clear_vlan(struct sw_flow_key *key) 487 { 488 key->eth.vlan.tci = 0; 489 key->eth.vlan.tpid = 0; 490 key->eth.cvlan.tci = 0; 491 key->eth.cvlan.tpid = 0; 492 } 493 494 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key) 495 { 496 int res; 497 498 if (skb_vlan_tag_present(skb)) { 499 key->eth.vlan.tci = htons(skb->vlan_tci) | htons(VLAN_CFI_MASK); 500 key->eth.vlan.tpid = skb->vlan_proto; 501 } else { 502 /* Parse outer vlan tag in the non-accelerated case. */ 503 res = parse_vlan_tag(skb, &key->eth.vlan, true); 504 if (res <= 0) 505 return res; 506 } 507 508 /* Parse inner vlan tag. */ 509 res = parse_vlan_tag(skb, &key->eth.cvlan, false); 510 if (res <= 0) 511 return res; 512 513 return 0; 514 } 515 516 static __be16 parse_ethertype(struct sk_buff *skb) 517 { 518 struct llc_snap_hdr { 519 u8 dsap; /* Always 0xAA */ 520 u8 ssap; /* Always 0xAA */ 521 u8 ctrl; 522 u8 oui[3]; 523 __be16 ethertype; 524 }; 525 struct llc_snap_hdr *llc; 526 __be16 proto; 527 528 proto = *(__be16 *) skb->data; 529 __skb_pull(skb, sizeof(__be16)); 530 531 if (eth_proto_is_802_3(proto)) 532 return proto; 533 534 if (skb->len < sizeof(struct llc_snap_hdr)) 535 return htons(ETH_P_802_2); 536 537 if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr)))) 538 return htons(0); 539 540 llc = (struct llc_snap_hdr *) skb->data; 541 if (llc->dsap != LLC_SAP_SNAP || 542 llc->ssap != LLC_SAP_SNAP || 543 (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0) 544 return htons(ETH_P_802_2); 545 546 __skb_pull(skb, sizeof(struct llc_snap_hdr)); 547 548 if (eth_proto_is_802_3(llc->ethertype)) 549 return llc->ethertype; 550 551 return htons(ETH_P_802_2); 552 } 553 554 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key, 555 int nh_len) 556 { 557 struct icmp6hdr *icmp = icmp6_hdr(skb); 558 559 /* The ICMPv6 type and code fields use the 16-bit transport port 560 * fields, so we need to store them in 16-bit network byte order. 561 */ 562 key->tp.src = htons(icmp->icmp6_type); 563 key->tp.dst = htons(icmp->icmp6_code); 564 565 if (icmp->icmp6_code == 0 && 566 (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION || 567 icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) { 568 int icmp_len = skb->len - skb_transport_offset(skb); 569 struct nd_msg *nd; 570 int offset; 571 572 memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd)); 573 574 /* In order to process neighbor discovery options, we need the 575 * entire packet. 576 */ 577 if (unlikely(icmp_len < sizeof(*nd))) 578 return 0; 579 580 if (unlikely(skb_linearize(skb))) 581 return -ENOMEM; 582 583 nd = (struct nd_msg *)skb_transport_header(skb); 584 key->ipv6.nd.target = nd->target; 585 586 icmp_len -= sizeof(*nd); 587 offset = 0; 588 while (icmp_len >= 8) { 589 struct nd_opt_hdr *nd_opt = 590 (struct nd_opt_hdr *)(nd->opt + offset); 591 int opt_len = nd_opt->nd_opt_len * 8; 592 593 if (unlikely(!opt_len || opt_len > icmp_len)) 594 return 0; 595 596 /* Store the link layer address if the appropriate 597 * option is provided. It is considered an error if 598 * the same link layer option is specified twice. 599 */ 600 if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR 601 && opt_len == 8) { 602 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll))) 603 goto invalid; 604 ether_addr_copy(key->ipv6.nd.sll, 605 &nd->opt[offset+sizeof(*nd_opt)]); 606 } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR 607 && opt_len == 8) { 608 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll))) 609 goto invalid; 610 ether_addr_copy(key->ipv6.nd.tll, 611 &nd->opt[offset+sizeof(*nd_opt)]); 612 } 613 614 icmp_len -= opt_len; 615 offset += opt_len; 616 } 617 } 618 619 return 0; 620 621 invalid: 622 memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target)); 623 memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll)); 624 memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll)); 625 626 return 0; 627 } 628 629 static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key) 630 { 631 struct nshhdr *nh; 632 unsigned int nh_ofs = skb_network_offset(skb); 633 u8 version, length; 634 int err; 635 636 err = check_header(skb, nh_ofs + NSH_BASE_HDR_LEN); 637 if (unlikely(err)) 638 return err; 639 640 nh = nsh_hdr(skb); 641 version = nsh_get_ver(nh); 642 length = nsh_hdr_len(nh); 643 644 if (version != 0) 645 return -EINVAL; 646 647 err = check_header(skb, nh_ofs + length); 648 if (unlikely(err)) 649 return err; 650 651 nh = nsh_hdr(skb); 652 key->nsh.base.flags = nsh_get_flags(nh); 653 key->nsh.base.ttl = nsh_get_ttl(nh); 654 key->nsh.base.mdtype = nh->mdtype; 655 key->nsh.base.np = nh->np; 656 key->nsh.base.path_hdr = nh->path_hdr; 657 switch (key->nsh.base.mdtype) { 658 case NSH_M_TYPE1: 659 if (length != NSH_M_TYPE1_LEN) 660 return -EINVAL; 661 memcpy(key->nsh.context, nh->md1.context, 662 sizeof(nh->md1)); 663 break; 664 case NSH_M_TYPE2: 665 memset(key->nsh.context, 0, 666 sizeof(nh->md1)); 667 break; 668 default: 669 return -EINVAL; 670 } 671 672 return 0; 673 } 674 675 /** 676 * key_extract_l3l4 - extracts L3/L4 header information. 677 * @skb: sk_buff that contains the frame, with skb->data pointing to the 678 * L3 header 679 * @key: output flow key 680 * 681 * Return: %0 if successful, otherwise a negative errno value. 682 */ 683 static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key) 684 { 685 int error; 686 687 /* Network layer. */ 688 if (key->eth.type == htons(ETH_P_IP)) { 689 struct iphdr *nh; 690 __be16 offset; 691 692 error = check_iphdr(skb); 693 if (unlikely(error)) { 694 memset(&key->ip, 0, sizeof(key->ip)); 695 memset(&key->ipv4, 0, sizeof(key->ipv4)); 696 if (error == -EINVAL) { 697 skb->transport_header = skb->network_header; 698 error = 0; 699 } 700 return error; 701 } 702 703 nh = ip_hdr(skb); 704 key->ipv4.addr.src = nh->saddr; 705 key->ipv4.addr.dst = nh->daddr; 706 707 key->ip.proto = nh->protocol; 708 key->ip.tos = nh->tos; 709 key->ip.ttl = nh->ttl; 710 711 offset = nh->frag_off & htons(IP_OFFSET); 712 if (offset) { 713 key->ip.frag = OVS_FRAG_TYPE_LATER; 714 memset(&key->tp, 0, sizeof(key->tp)); 715 return 0; 716 } 717 if (nh->frag_off & htons(IP_MF) || 718 skb_shinfo(skb)->gso_type & SKB_GSO_UDP) 719 key->ip.frag = OVS_FRAG_TYPE_FIRST; 720 else 721 key->ip.frag = OVS_FRAG_TYPE_NONE; 722 723 /* Transport layer. */ 724 if (key->ip.proto == IPPROTO_TCP) { 725 if (tcphdr_ok(skb)) { 726 struct tcphdr *tcp = tcp_hdr(skb); 727 key->tp.src = tcp->source; 728 key->tp.dst = tcp->dest; 729 key->tp.flags = TCP_FLAGS_BE16(tcp); 730 } else { 731 memset(&key->tp, 0, sizeof(key->tp)); 732 } 733 734 } else if (key->ip.proto == IPPROTO_UDP) { 735 if (udphdr_ok(skb)) { 736 struct udphdr *udp = udp_hdr(skb); 737 key->tp.src = udp->source; 738 key->tp.dst = udp->dest; 739 } else { 740 memset(&key->tp, 0, sizeof(key->tp)); 741 } 742 } else if (key->ip.proto == IPPROTO_SCTP) { 743 if (sctphdr_ok(skb)) { 744 struct sctphdr *sctp = sctp_hdr(skb); 745 key->tp.src = sctp->source; 746 key->tp.dst = sctp->dest; 747 } else { 748 memset(&key->tp, 0, sizeof(key->tp)); 749 } 750 } else if (key->ip.proto == IPPROTO_ICMP) { 751 if (icmphdr_ok(skb)) { 752 struct icmphdr *icmp = icmp_hdr(skb); 753 /* The ICMP type and code fields use the 16-bit 754 * transport port fields, so we need to store 755 * them in 16-bit network byte order. */ 756 key->tp.src = htons(icmp->type); 757 key->tp.dst = htons(icmp->code); 758 } else { 759 memset(&key->tp, 0, sizeof(key->tp)); 760 } 761 } 762 763 } else if (key->eth.type == htons(ETH_P_ARP) || 764 key->eth.type == htons(ETH_P_RARP)) { 765 struct arp_eth_header *arp; 766 bool arp_available = arphdr_ok(skb); 767 768 arp = (struct arp_eth_header *)skb_network_header(skb); 769 770 if (arp_available && 771 arp->ar_hrd == htons(ARPHRD_ETHER) && 772 arp->ar_pro == htons(ETH_P_IP) && 773 arp->ar_hln == ETH_ALEN && 774 arp->ar_pln == 4) { 775 776 /* We only match on the lower 8 bits of the opcode. */ 777 if (ntohs(arp->ar_op) <= 0xff) 778 key->ip.proto = ntohs(arp->ar_op); 779 else 780 key->ip.proto = 0; 781 782 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src)); 783 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst)); 784 ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha); 785 ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha); 786 } else { 787 memset(&key->ip, 0, sizeof(key->ip)); 788 memset(&key->ipv4, 0, sizeof(key->ipv4)); 789 } 790 } else if (eth_p_mpls(key->eth.type)) { 791 u8 label_count = 1; 792 793 memset(&key->mpls, 0, sizeof(key->mpls)); 794 skb_set_inner_network_header(skb, skb->mac_len); 795 while (1) { 796 __be32 lse; 797 798 error = check_header(skb, skb->mac_len + 799 label_count * MPLS_HLEN); 800 if (unlikely(error)) 801 return 0; 802 803 memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN); 804 805 if (label_count <= MPLS_LABEL_DEPTH) 806 memcpy(&key->mpls.lse[label_count - 1], &lse, 807 MPLS_HLEN); 808 809 skb_set_inner_network_header(skb, skb->mac_len + 810 label_count * MPLS_HLEN); 811 if (lse & htonl(MPLS_LS_S_MASK)) 812 break; 813 814 label_count++; 815 } 816 if (label_count > MPLS_LABEL_DEPTH) 817 label_count = MPLS_LABEL_DEPTH; 818 819 key->mpls.num_labels_mask = GENMASK(label_count - 1, 0); 820 } else if (key->eth.type == htons(ETH_P_IPV6)) { 821 int nh_len; /* IPv6 Header + Extensions */ 822 823 nh_len = parse_ipv6hdr(skb, key); 824 if (unlikely(nh_len < 0)) { 825 switch (nh_len) { 826 case -EINVAL: 827 memset(&key->ip, 0, sizeof(key->ip)); 828 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr)); 829 fallthrough; 830 case -EPROTO: 831 skb->transport_header = skb->network_header; 832 error = 0; 833 break; 834 default: 835 error = nh_len; 836 } 837 return error; 838 } 839 840 if (key->ip.frag == OVS_FRAG_TYPE_LATER) { 841 memset(&key->tp, 0, sizeof(key->tp)); 842 return 0; 843 } 844 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) 845 key->ip.frag = OVS_FRAG_TYPE_FIRST; 846 847 /* Transport layer. */ 848 if (key->ip.proto == NEXTHDR_TCP) { 849 if (tcphdr_ok(skb)) { 850 struct tcphdr *tcp = tcp_hdr(skb); 851 key->tp.src = tcp->source; 852 key->tp.dst = tcp->dest; 853 key->tp.flags = TCP_FLAGS_BE16(tcp); 854 } else { 855 memset(&key->tp, 0, sizeof(key->tp)); 856 } 857 } else if (key->ip.proto == NEXTHDR_UDP) { 858 if (udphdr_ok(skb)) { 859 struct udphdr *udp = udp_hdr(skb); 860 key->tp.src = udp->source; 861 key->tp.dst = udp->dest; 862 } else { 863 memset(&key->tp, 0, sizeof(key->tp)); 864 } 865 } else if (key->ip.proto == NEXTHDR_SCTP) { 866 if (sctphdr_ok(skb)) { 867 struct sctphdr *sctp = sctp_hdr(skb); 868 key->tp.src = sctp->source; 869 key->tp.dst = sctp->dest; 870 } else { 871 memset(&key->tp, 0, sizeof(key->tp)); 872 } 873 } else if (key->ip.proto == NEXTHDR_ICMP) { 874 if (icmp6hdr_ok(skb)) { 875 error = parse_icmpv6(skb, key, nh_len); 876 if (error) 877 return error; 878 } else { 879 memset(&key->tp, 0, sizeof(key->tp)); 880 } 881 } 882 } else if (key->eth.type == htons(ETH_P_NSH)) { 883 error = parse_nsh(skb, key); 884 if (error) 885 return error; 886 } 887 return 0; 888 } 889 890 /** 891 * key_extract - extracts a flow key from an Ethernet frame. 892 * @skb: sk_buff that contains the frame, with skb->data pointing to the 893 * Ethernet header 894 * @key: output flow key 895 * 896 * The caller must ensure that skb->len >= ETH_HLEN. 897 * 898 * Initializes @skb header fields as follows: 899 * 900 * - skb->mac_header: the L2 header. 901 * 902 * - skb->network_header: just past the L2 header, or just past the 903 * VLAN header, to the first byte of the L2 payload. 904 * 905 * - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6 906 * on output, then just past the IP header, if one is present and 907 * of a correct length, otherwise the same as skb->network_header. 908 * For other key->eth.type values it is left untouched. 909 * 910 * - skb->protocol: the type of the data starting at skb->network_header. 911 * Equals to key->eth.type. 912 * 913 * Return: %0 if successful, otherwise a negative errno value. 914 */ 915 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key) 916 { 917 struct ethhdr *eth; 918 919 /* Flags are always used as part of stats */ 920 key->tp.flags = 0; 921 922 skb_reset_mac_header(skb); 923 924 /* Link layer. */ 925 clear_vlan(key); 926 if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) { 927 if (unlikely(eth_type_vlan(skb->protocol))) 928 return -EINVAL; 929 930 skb_reset_network_header(skb); 931 key->eth.type = skb->protocol; 932 } else { 933 eth = eth_hdr(skb); 934 ether_addr_copy(key->eth.src, eth->h_source); 935 ether_addr_copy(key->eth.dst, eth->h_dest); 936 937 __skb_pull(skb, 2 * ETH_ALEN); 938 /* We are going to push all headers that we pull, so no need to 939 * update skb->csum here. 940 */ 941 942 if (unlikely(parse_vlan(skb, key))) 943 return -ENOMEM; 944 945 key->eth.type = parse_ethertype(skb); 946 if (unlikely(key->eth.type == htons(0))) 947 return -ENOMEM; 948 949 /* Multiple tagged packets need to retain TPID to satisfy 950 * skb_vlan_pop(), which will later shift the ethertype into 951 * skb->protocol. 952 */ 953 if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK)) 954 skb->protocol = key->eth.cvlan.tpid; 955 else 956 skb->protocol = key->eth.type; 957 958 skb_reset_network_header(skb); 959 __skb_push(skb, skb->data - skb_mac_header(skb)); 960 } 961 962 skb_reset_mac_len(skb); 963 964 /* Fill out L3/L4 key info, if any */ 965 return key_extract_l3l4(skb, key); 966 } 967 968 /* In the case of conntrack fragment handling it expects L3 headers, 969 * add a helper. 970 */ 971 int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key) 972 { 973 return key_extract_l3l4(skb, key); 974 } 975 976 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key) 977 { 978 int res; 979 980 res = key_extract(skb, key); 981 if (!res) 982 key->mac_proto &= ~SW_FLOW_KEY_INVALID; 983 984 return res; 985 } 986 987 static int key_extract_mac_proto(struct sk_buff *skb) 988 { 989 switch (skb->dev->type) { 990 case ARPHRD_ETHER: 991 return MAC_PROTO_ETHERNET; 992 case ARPHRD_NONE: 993 if (skb->protocol == htons(ETH_P_TEB)) 994 return MAC_PROTO_ETHERNET; 995 return MAC_PROTO_NONE; 996 } 997 WARN_ON_ONCE(1); 998 return -EINVAL; 999 } 1000 1001 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info, 1002 struct sk_buff *skb, struct sw_flow_key *key) 1003 { 1004 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT) 1005 struct tc_skb_ext *tc_ext; 1006 #endif 1007 bool post_ct = false, post_ct_snat = false, post_ct_dnat = false; 1008 int res, err; 1009 u16 zone = 0; 1010 1011 /* Extract metadata from packet. */ 1012 if (tun_info) { 1013 key->tun_proto = ip_tunnel_info_af(tun_info); 1014 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key)); 1015 1016 if (tun_info->options_len) { 1017 BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) * 1018 8)) - 1 1019 > sizeof(key->tun_opts)); 1020 1021 ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len), 1022 tun_info); 1023 key->tun_opts_len = tun_info->options_len; 1024 } else { 1025 key->tun_opts_len = 0; 1026 } 1027 } else { 1028 key->tun_proto = 0; 1029 key->tun_opts_len = 0; 1030 memset(&key->tun_key, 0, sizeof(key->tun_key)); 1031 } 1032 1033 key->phy.priority = skb->priority; 1034 key->phy.in_port = OVS_CB(skb)->input_vport->port_no; 1035 key->phy.skb_mark = skb->mark; 1036 key->ovs_flow_hash = 0; 1037 res = key_extract_mac_proto(skb); 1038 if (res < 0) 1039 return res; 1040 key->mac_proto = res; 1041 1042 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT) 1043 if (tc_skb_ext_tc_enabled()) { 1044 tc_ext = skb_ext_find(skb, TC_SKB_EXT); 1045 key->recirc_id = tc_ext && !tc_ext->act_miss ? 1046 tc_ext->chain : 0; 1047 OVS_CB(skb)->mru = tc_ext ? tc_ext->mru : 0; 1048 post_ct = tc_ext ? tc_ext->post_ct : false; 1049 post_ct_snat = post_ct ? tc_ext->post_ct_snat : false; 1050 post_ct_dnat = post_ct ? tc_ext->post_ct_dnat : false; 1051 zone = post_ct ? tc_ext->zone : 0; 1052 } else { 1053 key->recirc_id = 0; 1054 } 1055 #else 1056 key->recirc_id = 0; 1057 #endif 1058 1059 err = key_extract(skb, key); 1060 if (!err) { 1061 ovs_ct_fill_key(skb, key, post_ct); /* Must be after key_extract(). */ 1062 if (post_ct) { 1063 if (!skb_get_nfct(skb)) { 1064 key->ct_zone = zone; 1065 } else { 1066 if (!post_ct_dnat) 1067 key->ct_state &= ~OVS_CS_F_DST_NAT; 1068 if (!post_ct_snat) 1069 key->ct_state &= ~OVS_CS_F_SRC_NAT; 1070 } 1071 } 1072 } 1073 return err; 1074 } 1075 1076 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr, 1077 struct sk_buff *skb, 1078 struct sw_flow_key *key, bool log) 1079 { 1080 const struct nlattr *a[OVS_KEY_ATTR_MAX + 1]; 1081 u64 attrs = 0; 1082 int err; 1083 1084 err = parse_flow_nlattrs(attr, a, &attrs, log); 1085 if (err) 1086 return -EINVAL; 1087 1088 /* Extract metadata from netlink attributes. */ 1089 err = ovs_nla_get_flow_metadata(net, a, attrs, key, log); 1090 if (err) 1091 return err; 1092 1093 /* key_extract assumes that skb->protocol is set-up for 1094 * layer 3 packets which is the case for other callers, 1095 * in particular packets received from the network stack. 1096 * Here the correct value can be set from the metadata 1097 * extracted above. 1098 * For L2 packet key eth type would be zero. skb protocol 1099 * would be set to correct value later during key-extact. 1100 */ 1101 1102 skb->protocol = key->eth.type; 1103 err = key_extract(skb, key); 1104 if (err) 1105 return err; 1106 1107 /* Check that we have conntrack original direction tuple metadata only 1108 * for packets for which it makes sense. Otherwise the key may be 1109 * corrupted due to overlapping key fields. 1110 */ 1111 if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) && 1112 key->eth.type != htons(ETH_P_IP)) 1113 return -EINVAL; 1114 if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) && 1115 (key->eth.type != htons(ETH_P_IPV6) || 1116 sw_flow_key_is_nd(key))) 1117 return -EINVAL; 1118 1119 return 0; 1120 } 1121