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