linux/net/openvswitch/flow.c
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   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
  44u64 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
  59void 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;
 120unlock:
 121        spin_unlock(&stats->lock);
 122}
 123
 124/* Must be called with rcu_read_lock or ovs_mutex. */
 125void 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. */
 155void 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
 174static 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
 183static 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
 189static 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
 208static 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
 224static bool udphdr_ok(struct sk_buff *skb)
 225{
 226        return pskb_may_pull(skb, skb_transport_offset(skb) +
 227                                  sizeof(struct udphdr));
 228}
 229
 230static bool sctphdr_ok(struct sk_buff *skb)
 231{
 232        return pskb_may_pull(skb, skb_transport_offset(skb) +
 233                                  sizeof(struct sctphdr));
 234}
 235
 236static bool icmphdr_ok(struct sk_buff *skb)
 237{
 238        return pskb_may_pull(skb, skb_transport_offset(skb) +
 239                                  sizeof(struct icmphdr));
 240}
 241
 242static 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
 289static 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 */
 301static 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
 337static 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
 345static 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
 367static __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
 405static 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
 471invalid:
 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
 479static 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 */
 532static 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 */
 756static 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 */
 812int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
 813{
 814        return key_extract_l3l4(skb, key);
 815}
 816
 817int 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
 828static 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
 842int 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
 898int 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