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