flow.c

   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         memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
 565
 566         if (icmp->icmp6_code == 0 &&
 567             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 568              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 569                 int icmp_len = skb->len - skb_transport_offset(skb);
 570                 struct nd_msg *nd;
 571                 int offset;
 572
 573                 /* In order to process neighbor discovery options, we need the
 574                  * entire packet.
 575                  */
 576                 if (unlikely(icmp_len < sizeof(*nd)))
 577                         return 0;
 578
 579                 if (unlikely(skb_linearize(skb)))
 580                         return -ENOMEM;
 581
 582                 nd = (struct nd_msg *)skb_transport_header(skb);
 583                 key->ipv6.nd.target = nd->target;
 584
 585                 icmp_len -= sizeof(*nd);
 586                 offset = 0;
 587                 while (icmp_len >= 8) {
 588                         struct nd_opt_hdr *nd_opt =
 589                                  (struct nd_opt_hdr *)(nd->opt + offset);
 590                         int opt_len = nd_opt->nd_opt_len * 8;
 591
 592                         if (unlikely(!opt_len || opt_len > icmp_len))
 593                                 return 0;
 594
 595                         /* Store the link layer address if the appropriate
 596                          * option is provided.  It is considered an error if
 597                          * the same link layer option is specified twice.
 598                          */
 599                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 600                             && opt_len == 8) {
 601                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 602                                         goto invalid;
 603                                 ether_addr_copy(key->ipv6.nd.sll,
 604                                                 &nd->opt[offset+sizeof(*nd_opt)]);
 605                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 606                                    && opt_len == 8) {
 607                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 608                                         goto invalid;
 609                                 ether_addr_copy(key->ipv6.nd.tll,
 610                                                 &nd->opt[offset+sizeof(*nd_opt)]);
 611                         }
 612
 613                         icmp_len -= opt_len;
 614                         offset += opt_len;
 615                 }
 616         }
 617
 618         return 0;
 619
 620 invalid:
 621         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 622         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 623         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 624
 625         return 0;
 626 }
 627
 628 static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 629 {
 630         struct nshhdr *nh;
 631         unsigned int nh_ofs = skb_network_offset(skb);
 632         u8 version, length;
 633         int err;
 634
 635         err = check_header(skb, nh_ofs + NSH_BASE_HDR_LEN);
 636         if (unlikely(err))
 637                 return err;
 638
 639         nh = nsh_hdr(skb);
 640         version = nsh_get_ver(nh);
 641         length = nsh_hdr_len(nh);
 642
 643         if (version != 0)
 644                 return -EINVAL;
 645
 646         err = check_header(skb, nh_ofs + length);
 647         if (unlikely(err))
 648                 return err;
 649
 650         nh = nsh_hdr(skb);
 651         key->nsh.base.flags = nsh_get_flags(nh);
 652         key->nsh.base.ttl = nsh_get_ttl(nh);
 653         key->nsh.base.mdtype = nh->mdtype;
 654         key->nsh.base.np = nh->np;
 655         key->nsh.base.path_hdr = nh->path_hdr;
 656         switch (key->nsh.base.mdtype) {
 657         case NSH_M_TYPE1:
 658                 if (length != NSH_M_TYPE1_LEN)
 659                         return -EINVAL;
 660                 memcpy(key->nsh.context, nh->md1.context,
 661                        sizeof(nh->md1));
 662                 break;
 663         case NSH_M_TYPE2:
 664                 memset(key->nsh.context, 0,
 665                        sizeof(nh->md1));
 666                 break;
 667         default:
 668                 return -EINVAL;
 669         }
 670
 671         return 0;
 672 }
 673
 674 /**
 675  * key_extract_l3l4 - extracts L3/L4 header information.
 676  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 677  *       L3 header
 678  * @key: output flow key
 679  *
 680  * Return: %0 if successful, otherwise a negative errno value.
 681  */
 682 static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
 683 {
 684         int error;
 685
 686         /* Network layer. */
 687         if (key->eth.type == htons(ETH_P_IP)) {
 688                 struct iphdr *nh;
 689                 __be16 offset;
 690
 691                 error = check_iphdr(skb);
 692                 if (unlikely(error)) {
 693                         memset(&key->ip, 0, sizeof(key->ip));
 694                         memset(&key->ipv4, 0, sizeof(key->ipv4));
 695                         if (error == -EINVAL) {
 696                                 skb->transport_header = skb->network_header;
 697                                 error = 0;
 698                         }
 699                         return error;
 700                 }
 701
 702                 nh = ip_hdr(skb);
 703                 key->ipv4.addr.src = nh->saddr;
 704                 key->ipv4.addr.dst = nh->daddr;
 705
 706                 key->ip.proto = nh->protocol;
 707                 key->ip.tos = nh->tos;
 708                 key->ip.ttl = nh->ttl;
 709
 710                 offset = nh->frag_off & htons(IP_OFFSET);
 711                 if (offset) {
 712                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 713                         memset(&key->tp, 0, sizeof(key->tp));
 714                         return 0;
 715                 }
 716                 if (nh->frag_off & htons(IP_MF) ||
 717                         skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 718                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 719                 else
 720                         key->ip.frag = OVS_FRAG_TYPE_NONE;
 721
 722                 /* Transport layer. */
 723                 if (key->ip.proto == IPPROTO_TCP) {
 724                         if (tcphdr_ok(skb)) {
 725                                 struct tcphdr *tcp = tcp_hdr(skb);
 726                                 key->tp.src = tcp->source;
 727                                 key->tp.dst = tcp->dest;
 728                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
 729                         } else {
 730                                 memset(&key->tp, 0, sizeof(key->tp));
 731                         }
 732
 733                 } else if (key->ip.proto == IPPROTO_UDP) {
 734                         if (udphdr_ok(skb)) {
 735                                 struct udphdr *udp = udp_hdr(skb);
 736                                 key->tp.src = udp->source;
 737                                 key->tp.dst = udp->dest;
 738                         } else {
 739                                 memset(&key->tp, 0, sizeof(key->tp));
 740                         }
 741                 } else if (key->ip.proto == IPPROTO_SCTP) {
 742                         if (sctphdr_ok(skb)) {
 743                                 struct sctphdr *sctp = sctp_hdr(skb);
 744                                 key->tp.src = sctp->source;
 745                                 key->tp.dst = sctp->dest;
 746                         } else {
 747                                 memset(&key->tp, 0, sizeof(key->tp));
 748                         }
 749                 } else if (key->ip.proto == IPPROTO_ICMP) {
 750                         if (icmphdr_ok(skb)) {
 751                                 struct icmphdr *icmp = icmp_hdr(skb);
 752                                 /* The ICMP type and code fields use the 16-bit
 753                                  * transport port fields, so we need to store
 754                                  * them in 16-bit network byte order. */
 755                                 key->tp.src = htons(icmp->type);
 756                                 key->tp.dst = htons(icmp->code);
 757                         } else {
 758                                 memset(&key->tp, 0, sizeof(key->tp));
 759                         }
 760                 }
 761
 762         } else if (key->eth.type == htons(ETH_P_ARP) ||
 763                    key->eth.type == htons(ETH_P_RARP)) {
 764                 struct arp_eth_header *arp;
 765                 bool arp_available = arphdr_ok(skb);
 766
 767                 arp = (struct arp_eth_header *)skb_network_header(skb);
 768
 769                 if (arp_available &&
 770                     arp->ar_hrd == htons(ARPHRD_ETHER) &&
 771                     arp->ar_pro == htons(ETH_P_IP) &&
 772                     arp->ar_hln == ETH_ALEN &&
 773                     arp->ar_pln == 4) {
 774
 775                         /* We only match on the lower 8 bits of the opcode. */
 776                         if (ntohs(arp->ar_op) <= 0xff)
 777                                 key->ip.proto = ntohs(arp->ar_op);
 778                         else
 779                                 key->ip.proto = 0;
 780
 781                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 782                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 783                         ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
 784                         ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
 785                 } else {
 786                         memset(&key->ip, 0, sizeof(key->ip));
 787                         memset(&key->ipv4, 0, sizeof(key->ipv4));
 788                 }
 789         } else if (eth_p_mpls(key->eth.type)) {
 790                 u8 label_count = 1;
 791
 792                 memset(&key->mpls, 0, sizeof(key->mpls));
 793                 skb_set_inner_network_header(skb, skb->mac_len);
 794                 while (1) {
 795                         __be32 lse;
 796
 797                         error = check_header(skb, skb->mac_len +
 798                                              label_count * MPLS_HLEN);
 799                         if (unlikely(error))
 800                                 return 0;
 801
 802                         memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
 803
 804                         if (label_count <= MPLS_LABEL_DEPTH)
 805                                 memcpy(&key->mpls.lse[label_count - 1], &lse,
 806                                        MPLS_HLEN);
 807
 808                         skb_set_inner_network_header(skb, skb->mac_len +
 809                                                      label_count * MPLS_HLEN);
 810                         if (lse & htonl(MPLS_LS_S_MASK))
 811                                 break;
 812
 813                         label_count++;
 814                 }
 815                 if (label_count > MPLS_LABEL_DEPTH)
 816                         label_count = MPLS_LABEL_DEPTH;
 817
 818                 key->mpls.num_labels_mask = GENMASK(label_count - 1, 0);
 819         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 820                 int nh_len;             /* IPv6 Header + Extensions */
 821
 822                 nh_len = parse_ipv6hdr(skb, key);
 823                 if (unlikely(nh_len < 0)) {
 824                         switch (nh_len) {
 825                         case -EINVAL:
 826                                 memset(&key->ip, 0, sizeof(key->ip));
 827                                 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
 828                                 fallthrough;
 829                         case -EPROTO:
 830                                 skb->transport_header = skb->network_header;
 831                                 error = 0;
 832                                 break;
 833                         default:
 834                                 error = nh_len;
 835                         }
 836                         return error;
 837                 }
 838
 839                 if (key->ip.frag == OVS_FRAG_TYPE_LATER) {
 840                         memset(&key->tp, 0, sizeof(key->tp));
 841                         return 0;
 842                 }
 843                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 844                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 845
 846                 /* Transport layer. */
 847                 if (key->ip.proto == NEXTHDR_TCP) {
 848                         if (tcphdr_ok(skb)) {
 849                                 struct tcphdr *tcp = tcp_hdr(skb);
 850                                 key->tp.src = tcp->source;
 851                                 key->tp.dst = tcp->dest;
 852                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
 853                         } else {
 854                                 memset(&key->tp, 0, sizeof(key->tp));
 855                         }
 856                 } else if (key->ip.proto == NEXTHDR_UDP) {
 857                         if (udphdr_ok(skb)) {
 858                                 struct udphdr *udp = udp_hdr(skb);
 859                                 key->tp.src = udp->source;
 860                                 key->tp.dst = udp->dest;
 861                         } else {
 862                                 memset(&key->tp, 0, sizeof(key->tp));
 863                         }
 864                 } else if (key->ip.proto == NEXTHDR_SCTP) {
 865                         if (sctphdr_ok(skb)) {
 866                                 struct sctphdr *sctp = sctp_hdr(skb);
 867                                 key->tp.src = sctp->source;
 868                                 key->tp.dst = sctp->dest;
 869                         } else {
 870                                 memset(&key->tp, 0, sizeof(key->tp));
 871                         }
 872                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 873                         if (icmp6hdr_ok(skb)) {
 874                                 error = parse_icmpv6(skb, key, nh_len);
 875                                 if (error)
 876                                         return error;
 877                         } else {
 878                                 memset(&key->tp, 0, sizeof(key->tp));
 879                         }
 880                 }
 881         } else if (key->eth.type == htons(ETH_P_NSH)) {
 882                 error = parse_nsh(skb, key);
 883                 if (error)
 884                         return error;
 885         }
 886         return 0;
 887 }
 888
 889 /**
 890  * key_extract - extracts a flow key from an Ethernet frame.
 891  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 892  * Ethernet header
 893  * @key: output flow key
 894  *
 895  * The caller must ensure that skb->len >= ETH_HLEN.
 896  *
 897  * Initializes @skb header fields as follows:
 898  *
 899  *    - skb->mac_header: the L2 header.
 900  *
 901  *    - skb->network_header: just past the L2 header, or just past the
 902  *      VLAN header, to the first byte of the L2 payload.
 903  *
 904  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
 905  *      on output, then just past the IP header, if one is present and
 906  *      of a correct length, otherwise the same as skb->network_header.
 907  *      For other key->eth.type values it is left untouched.
 908  *
 909  *    - skb->protocol: the type of the data starting at skb->network_header.
 910  *      Equals to key->eth.type.
 911  *
 912  * Return: %0 if successful, otherwise a negative errno value.
 913  */
 914 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
 915 {
 916         struct ethhdr *eth;
 917
 918         /* Flags are always used as part of stats */
 919         key->tp.flags = 0;
 920
 921         skb_reset_mac_header(skb);
 922
 923         /* Link layer. */
 924         clear_vlan(key);
 925         if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
 926                 if (unlikely(eth_type_vlan(skb->protocol)))
 927                         return -EINVAL;
 928
 929                 skb_reset_network_header(skb);
 930                 key->eth.type = skb->protocol;
 931         } else {
 932                 eth = eth_hdr(skb);
 933                 ether_addr_copy(key->eth.src, eth->h_source);
 934                 ether_addr_copy(key->eth.dst, eth->h_dest);
 935
 936                 __skb_pull(skb, 2 * ETH_ALEN);
 937                 /* We are going to push all headers that we pull, so no need to
 938                  * update skb->csum here.
 939                  */
 940
 941                 if (unlikely(parse_vlan(skb, key)))
 942                         return -ENOMEM;
 943
 944                 key->eth.type = parse_ethertype(skb);
 945                 if (unlikely(key->eth.type == htons(0)))
 946                         return -ENOMEM;
 947
 948                 /* Multiple tagged packets need to retain TPID to satisfy
 949                  * skb_vlan_pop(), which will later shift the ethertype into
 950                  * skb->protocol.
 951                  */
 952                 if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK))
 953                         skb->protocol = key->eth.cvlan.tpid;
 954                 else
 955                         skb->protocol = key->eth.type;
 956
 957                 skb_reset_network_header(skb);
 958                 __skb_push(skb, skb->data - skb_mac_header(skb));
 959         }
 960
 961         skb_reset_mac_len(skb);
 962
 963         /* Fill out L3/L4 key info, if any */
 964         return key_extract_l3l4(skb, key);
 965 }
 966
 967 /* In the case of conntrack fragment handling it expects L3 headers,
 968  * add a helper.
 969  */
 970 int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
 971 {
 972         return key_extract_l3l4(skb, key);
 973 }
 974
 975 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
 976 {
 977         int res;
 978
 979         res = key_extract(skb, key);
 980         if (!res)
 981                 key->mac_proto &= ~SW_FLOW_KEY_INVALID;
 982
 983         return res;
 984 }
 985
 986 static int key_extract_mac_proto(struct sk_buff *skb)
 987 {
 988         switch (skb->dev->type) {
 989         case ARPHRD_ETHER:
 990                 return MAC_PROTO_ETHERNET;
 991         case ARPHRD_NONE:
 992                 if (skb->protocol == htons(ETH_P_TEB))
 993                         return MAC_PROTO_ETHERNET;
 994                 return MAC_PROTO_NONE;
 995         }
 996         WARN_ON_ONCE(1);
 997         return -EINVAL;
 998 }
 999
1000 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
1001                          struct sk_buff *skb, struct sw_flow_key *key)
1002 {
1003 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1004         struct tc_skb_ext *tc_ext;
1005 #endif
1006         bool post_ct = false, post_ct_snat = false, post_ct_dnat = false;
1007         int res, err;
1008         u16 zone = 0;
1009
1010         /* Extract metadata from packet. */
1011         if (tun_info) {
1012                 key->tun_proto = ip_tunnel_info_af(tun_info);
1013                 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
1014
1015                 if (tun_info->options_len) {
1016                         BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
1017                                                    8)) - 1
1018                                         > sizeof(key->tun_opts));
1019
1020                         ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
1021                                                 tun_info);
1022                         key->tun_opts_len = tun_info->options_len;
1023                 } else {
1024                         key->tun_opts_len = 0;
1025                 }
1026         } else  {
1027                 key->tun_proto = 0;
1028                 key->tun_opts_len = 0;
1029                 memset(&key->tun_key, 0, sizeof(key->tun_key));
1030         }
1031
1032         key->phy.priority = skb->priority;
1033         key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
1034         key->phy.skb_mark = skb->mark;
1035         key->ovs_flow_hash = 0;
1036         res = key_extract_mac_proto(skb);
1037         if (res < 0)
1038                 return res;
1039         key->mac_proto = res;
1040
1041 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1042         if (tc_skb_ext_tc_enabled()) {
1043                 tc_ext = skb_ext_find(skb, TC_SKB_EXT);
1044                 key->recirc_id = tc_ext && !tc_ext->act_miss ?
1045                                  tc_ext->chain : 0;
1046                 OVS_CB(skb)->mru = tc_ext ? tc_ext->mru : 0;
1047                 post_ct = tc_ext ? tc_ext->post_ct : false;
1048                 post_ct_snat = post_ct ? tc_ext->post_ct_snat : false;
1049                 post_ct_dnat = post_ct ? tc_ext->post_ct_dnat : false;
1050                 zone = post_ct ? tc_ext->zone : 0;
1051         } else {
1052                 key->recirc_id = 0;
1053         }
1054 #else
1055         key->recirc_id = 0;
1056 #endif
1057
1058         err = key_extract(skb, key);
1059         if (!err) {
1060                 ovs_ct_fill_key(skb, key, post_ct);   /* Must be after key_extract(). */
1061                 if (post_ct) {
1062                         if (!skb_get_nfct(skb)) {
1063                                 key->ct_zone = zone;
1064                         } else {
1065                                 if (!post_ct_dnat)
1066                                         key->ct_state &= ~OVS_CS_F_DST_NAT;
1067                                 if (!post_ct_snat)
1068                                         key->ct_state &= ~OVS_CS_F_SRC_NAT;
1069                         }
1070                 }
1071         }
1072         return err;
1073 }
1074
1075 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
1076                                    struct sk_buff *skb,
1077                                    struct sw_flow_key *key, bool log)
1078 {
1079         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
1080         u64 attrs = 0;
1081         int err;
1082
1083         err = parse_flow_nlattrs(attr, a, &attrs, log);
1084         if (err)
1085                 return -EINVAL;
1086
1087         /* Extract metadata from netlink attributes. */
1088         err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
1089         if (err)
1090                 return err;
1091
1092         /* key_extract assumes that skb->protocol is set-up for
1093          * layer 3 packets which is the case for other callers,
1094          * in particular packets received from the network stack.
1095          * Here the correct value can be set from the metadata
1096          * extracted above.
1097          * For L2 packet key eth type would be zero. skb protocol
1098          * would be set to correct value later during key-extact.
1099          */
1100
1101         skb->protocol = key->eth.type;
1102         err = key_extract(skb, key);
1103         if (err)
1104                 return err;
1105
1106         /* Check that we have conntrack original direction tuple metadata only
1107          * for packets for which it makes sense.  Otherwise the key may be
1108          * corrupted due to overlapping key fields.
1109          */
1110         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
1111             key->eth.type != htons(ETH_P_IP))
1112                 return -EINVAL;
1113         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
1114             (key->eth.type != htons(ETH_P_IPV6) ||
1115              sw_flow_key_is_nd(key)))
1116                 return -EINVAL;
1117
1118         return 0;
1119 }