openvswitch/conntrack.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2015 Nicira, Inc.
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/openvswitch.h>
   8 #include <linux/tcp.h>
   9 #include <linux/udp.h>
  10 #include <linux/sctp.h>
  11 #include <linux/static_key.h>
  12 #include <net/ip.h>
  13 #include <net/genetlink.h>
  14 #include <net/netfilter/nf_conntrack_core.h>
  15 #include <net/netfilter/nf_conntrack_count.h>
  16 #include <net/netfilter/nf_conntrack_helper.h>
  17 #include <net/netfilter/nf_conntrack_labels.h>
  18 #include <net/netfilter/nf_conntrack_seqadj.h>
  19 #include <net/netfilter/nf_conntrack_timeout.h>
  20 #include <net/netfilter/nf_conntrack_zones.h>
  21 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  22 #include <net/ipv6_frag.h>
  23
  24 #if IS_ENABLED(CONFIG_NF_NAT)
  25 #include <net/netfilter/nf_nat.h>
  26 #endif
  27
  28 #include <net/netfilter/nf_conntrack_act_ct.h>
  29
  30 #include "datapath.h"
  31 #include "conntrack.h"
  32 #include "flow.h"
  33 #include "flow_netlink.h"
  34
  35 struct ovs_ct_len_tbl {
  36         int maxlen;
  37         int minlen;
  38 };
  39
  40 /* Metadata mark for masked write to conntrack mark */
  41 struct md_mark {
  42         u32 value;
  43         u32 mask;
  44 };
  45
  46 /* Metadata label for masked write to conntrack label. */
  47 struct md_labels {
  48         struct ovs_key_ct_labels value;
  49         struct ovs_key_ct_labels mask;
  50 };
  51
  52 enum ovs_ct_nat {
  53         OVS_CT_NAT = 1 << 0,     /* NAT for committed connections only. */
  54         OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */
  55         OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */
  56 };
  57
  58 /* Conntrack action context for execution. */
  59 struct ovs_conntrack_info {
  60         struct nf_conntrack_helper *helper;
  61         struct nf_conntrack_zone zone;
  62         struct nf_conn *ct;
  63         u8 commit : 1;
  64         u8 nat : 3;                 /* enum ovs_ct_nat */
  65         u8 force : 1;
  66         u8 have_eventmask : 1;
  67         u16 family;
  68         u32 eventmask;              /* Mask of 1 << IPCT_*. */
  69         struct md_mark mark;
  70         struct md_labels labels;
  71         char timeout[CTNL_TIMEOUT_NAME_MAX];
  72         struct nf_ct_timeout *nf_ct_timeout;
  73 #if IS_ENABLED(CONFIG_NF_NAT)
  74         struct nf_nat_range2 range;  /* Only present for SRC NAT and DST NAT. */
  75 #endif
  76 };
  77
  78 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
  79 #define OVS_CT_LIMIT_UNLIMITED  0
  80 #define OVS_CT_LIMIT_DEFAULT OVS_CT_LIMIT_UNLIMITED
  81 #define CT_LIMIT_HASH_BUCKETS 512
  82 static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled);
  83
  84 struct ovs_ct_limit {
  85         /* Elements in ovs_ct_limit_info->limits hash table */
  86         struct hlist_node hlist_node;
  87         struct rcu_head rcu;
  88         u16 zone;
  89         u32 limit;
  90 };
  91
  92 struct ovs_ct_limit_info {
  93         u32 default_limit;
  94         struct hlist_head *limits;
  95         struct nf_conncount_data *data;
  96 };
  97
  98 static const struct nla_policy ct_limit_policy[OVS_CT_LIMIT_ATTR_MAX + 1] = {
  99         [OVS_CT_LIMIT_ATTR_ZONE_LIMIT] = { .type = NLA_NESTED, },
 100 };
 101 #endif
 102
 103 static bool labels_nonzero(const struct ovs_key_ct_labels *labels);
 104
 105 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
 106
 107 static u16 key_to_nfproto(const struct sw_flow_key *key)
 108 {
 109         switch (ntohs(key->eth.type)) {
 110         case ETH_P_IP:
 111                 return NFPROTO_IPV4;
 112         case ETH_P_IPV6:
 113                 return NFPROTO_IPV6;
 114         default:
 115                 return NFPROTO_UNSPEC;
 116         }
 117 }
 118
 119 /* Map SKB connection state into the values used by flow definition. */
 120 static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
 121 {
 122         u8 ct_state = OVS_CS_F_TRACKED;
 123
 124         switch (ctinfo) {
 125         case IP_CT_ESTABLISHED_REPLY:
 126         case IP_CT_RELATED_REPLY:
 127                 ct_state |= OVS_CS_F_REPLY_DIR;
 128                 break;
 129         default:
 130                 break;
 131         }
 132
 133         switch (ctinfo) {
 134         case IP_CT_ESTABLISHED:
 135         case IP_CT_ESTABLISHED_REPLY:
 136                 ct_state |= OVS_CS_F_ESTABLISHED;
 137                 break;
 138         case IP_CT_RELATED:
 139         case IP_CT_RELATED_REPLY:
 140                 ct_state |= OVS_CS_F_RELATED;
 141                 break;
 142         case IP_CT_NEW:
 143                 ct_state |= OVS_CS_F_NEW;
 144                 break;
 145         default:
 146                 break;
 147         }
 148
 149         return ct_state;
 150 }
 151
 152 static u32 ovs_ct_get_mark(const struct nf_conn *ct)
 153 {
 154 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 155         return ct ? READ_ONCE(ct->mark) : 0;
 156 #else
 157         return 0;
 158 #endif
 159 }
 160
 161 /* Guard against conntrack labels max size shrinking below 128 bits. */
 162 #if NF_CT_LABELS_MAX_SIZE < 16
 163 #error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes
 164 #endif
 165
 166 static void ovs_ct_get_labels(const struct nf_conn *ct,
 167                               struct ovs_key_ct_labels *labels)
 168 {
 169         struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL;
 170
 171         if (cl)
 172                 memcpy(labels, cl->bits, OVS_CT_LABELS_LEN);
 173         else
 174                 memset(labels, 0, OVS_CT_LABELS_LEN);
 175 }
 176
 177 static void __ovs_ct_update_key_orig_tp(struct sw_flow_key *key,
 178                                         const struct nf_conntrack_tuple *orig,
 179                                         u8 icmp_proto)
 180 {
 181         key->ct_orig_proto = orig->dst.protonum;
 182         if (orig->dst.protonum == icmp_proto) {
 183                 key->ct.orig_tp.src = htons(orig->dst.u.icmp.type);
 184                 key->ct.orig_tp.dst = htons(orig->dst.u.icmp.code);
 185         } else {
 186                 key->ct.orig_tp.src = orig->src.u.all;
 187                 key->ct.orig_tp.dst = orig->dst.u.all;
 188         }
 189 }
 190
 191 static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
 192                                 const struct nf_conntrack_zone *zone,
 193                                 const struct nf_conn *ct)
 194 {
 195         key->ct_state = state;
 196         key->ct_zone = zone->id;
 197         key->ct.mark = ovs_ct_get_mark(ct);
 198         ovs_ct_get_labels(ct, &key->ct.labels);
 199
 200         if (ct) {
 201                 const struct nf_conntrack_tuple *orig;
 202
 203                 /* Use the master if we have one. */
 204                 if (ct->master)
 205                         ct = ct->master;
 206                 orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
 207
 208                 /* IP version must match with the master connection. */
 209                 if (key->eth.type == htons(ETH_P_IP) &&
 210                     nf_ct_l3num(ct) == NFPROTO_IPV4) {
 211                         key->ipv4.ct_orig.src = orig->src.u3.ip;
 212                         key->ipv4.ct_orig.dst = orig->dst.u3.ip;
 213                         __ovs_ct_update_key_orig_tp(key, orig, IPPROTO_ICMP);
 214                         return;
 215                 } else if (key->eth.type == htons(ETH_P_IPV6) &&
 216                            !sw_flow_key_is_nd(key) &&
 217                            nf_ct_l3num(ct) == NFPROTO_IPV6) {
 218                         key->ipv6.ct_orig.src = orig->src.u3.in6;
 219                         key->ipv6.ct_orig.dst = orig->dst.u3.in6;
 220                         __ovs_ct_update_key_orig_tp(key, orig, NEXTHDR_ICMP);
 221                         return;
 222                 }
 223         }
 224         /* Clear 'ct_orig_proto' to mark the non-existence of conntrack
 225          * original direction key fields.
 226          */
 227         key->ct_orig_proto = 0;
 228 }
 229
 230 /* Update 'key' based on skb->_nfct.  If 'post_ct' is true, then OVS has
 231  * previously sent the packet to conntrack via the ct action.  If
 232  * 'keep_nat_flags' is true, the existing NAT flags retained, else they are
 233  * initialized from the connection status.
 234  */
 235 static void ovs_ct_update_key(const struct sk_buff *skb,
 236                               const struct ovs_conntrack_info *info,
 237                               struct sw_flow_key *key, bool post_ct,
 238                               bool keep_nat_flags)
 239 {
 240         const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
 241         enum ip_conntrack_info ctinfo;
 242         struct nf_conn *ct;
 243         u8 state = 0;
 244
 245         ct = nf_ct_get(skb, &ctinfo);
 246         if (ct) {
 247                 state = ovs_ct_get_state(ctinfo);
 248                 /* All unconfirmed entries are NEW connections. */
 249                 if (!nf_ct_is_confirmed(ct))
 250                         state |= OVS_CS_F_NEW;
 251                 /* OVS persists the related flag for the duration of the
 252                  * connection.
 253                  */
 254                 if (ct->master)
 255                         state |= OVS_CS_F_RELATED;
 256                 if (keep_nat_flags) {
 257                         state |= key->ct_state & OVS_CS_F_NAT_MASK;
 258                 } else {
 259                         if (ct->status & IPS_SRC_NAT)
 260                                 state |= OVS_CS_F_SRC_NAT;
 261                         if (ct->status & IPS_DST_NAT)
 262                                 state |= OVS_CS_F_DST_NAT;
 263                 }
 264                 zone = nf_ct_zone(ct);
 265         } else if (post_ct) {
 266                 state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
 267                 if (info)
 268                         zone = &info->zone;
 269         }
 270         __ovs_ct_update_key(key, state, zone, ct);
 271 }
 272
 273 /* This is called to initialize CT key fields possibly coming in from the local
 274  * stack.
 275  */
 276 void ovs_ct_fill_key(const struct sk_buff *skb,
 277                      struct sw_flow_key *key,
 278                      bool post_ct)
 279 {
 280         ovs_ct_update_key(skb, NULL, key, post_ct, false);
 281 }
 282
 283 int ovs_ct_put_key(const struct sw_flow_key *swkey,
 284                    const struct sw_flow_key *output, struct sk_buff *skb)
 285 {
 286         if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state))
 287                 return -EMSGSIZE;
 288
 289         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
 290             nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone))
 291                 return -EMSGSIZE;
 292
 293         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
 294             nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark))
 295                 return -EMSGSIZE;
 296
 297         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
 298             nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels),
 299                     &output->ct.labels))
 300                 return -EMSGSIZE;
 301
 302         if (swkey->ct_orig_proto) {
 303                 if (swkey->eth.type == htons(ETH_P_IP)) {
 304                         struct ovs_key_ct_tuple_ipv4 orig;
 305
 306                         memset(&orig, 0, sizeof(orig));
 307                         orig.ipv4_src = output->ipv4.ct_orig.src;
 308                         orig.ipv4_dst = output->ipv4.ct_orig.dst;
 309                         orig.src_port = output->ct.orig_tp.src;
 310                         orig.dst_port = output->ct.orig_tp.dst;
 311                         orig.ipv4_proto = output->ct_orig_proto;
 312
 313                         if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4,
 314                                     sizeof(orig), &orig))
 315                                 return -EMSGSIZE;
 316                 } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
 317                         struct ovs_key_ct_tuple_ipv6 orig;
 318
 319                         memset(&orig, 0, sizeof(orig));
 320                         memcpy(orig.ipv6_src, output->ipv6.ct_orig.src.s6_addr32,
 321                                sizeof(orig.ipv6_src));
 322                         memcpy(orig.ipv6_dst, output->ipv6.ct_orig.dst.s6_addr32,
 323                                sizeof(orig.ipv6_dst));
 324                         orig.src_port = output->ct.orig_tp.src;
 325                         orig.dst_port = output->ct.orig_tp.dst;
 326                         orig.ipv6_proto = output->ct_orig_proto;
 327
 328                         if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6,
 329                                     sizeof(orig), &orig))
 330                                 return -EMSGSIZE;
 331                 }
 332         }
 333
 334         return 0;
 335 }
 336
 337 static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key,
 338                            u32 ct_mark, u32 mask)
 339 {
 340 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 341         u32 new_mark;
 342
 343         new_mark = ct_mark | (READ_ONCE(ct->mark) & ~(mask));
 344         if (READ_ONCE(ct->mark) != new_mark) {
 345                 WRITE_ONCE(ct->mark, new_mark);
 346                 if (nf_ct_is_confirmed(ct))
 347                         nf_conntrack_event_cache(IPCT_MARK, ct);
 348                 key->ct.mark = new_mark;
 349         }
 350
 351         return 0;
 352 #else
 353         return -ENOTSUPP;
 354 #endif
 355 }
 356
 357 static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct)
 358 {
 359         struct nf_conn_labels *cl;
 360
 361         cl = nf_ct_labels_find(ct);
 362         if (!cl) {
 363                 nf_ct_labels_ext_add(ct);
 364                 cl = nf_ct_labels_find(ct);
 365         }
 366
 367         return cl;
 368 }
 369
 370 /* Initialize labels for a new, yet to be committed conntrack entry.  Note that
 371  * since the new connection is not yet confirmed, and thus no-one else has
 372  * access to it's labels, we simply write them over.
 373  */
 374 static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key,
 375                               const struct ovs_key_ct_labels *labels,
 376                               const struct ovs_key_ct_labels *mask)
 377 {
 378         struct nf_conn_labels *cl, *master_cl;
 379         bool have_mask = labels_nonzero(mask);
 380
 381         /* Inherit master's labels to the related connection? */
 382         master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL;
 383
 384         if (!master_cl && !have_mask)
 385                 return 0;   /* Nothing to do. */
 386
 387         cl = ovs_ct_get_conn_labels(ct);
 388         if (!cl)
 389                 return -ENOSPC;
 390
 391         /* Inherit the master's labels, if any. */
 392         if (master_cl)
 393                 *cl = *master_cl;
 394
 395         if (have_mask) {
 396                 u32 *dst = (u32 *)cl->bits;
 397                 int i;
 398
 399                 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
 400                         dst[i] = (dst[i] & ~mask->ct_labels_32[i]) |
 401                                 (labels->ct_labels_32[i]
 402                                  & mask->ct_labels_32[i]);
 403         }
 404
 405         /* Labels are included in the IPCTNL_MSG_CT_NEW event only if the
 406          * IPCT_LABEL bit is set in the event cache.
 407          */
 408         nf_conntrack_event_cache(IPCT_LABEL, ct);
 409
 410         memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
 411
 412         return 0;
 413 }
 414
 415 static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key,
 416                              const struct ovs_key_ct_labels *labels,
 417                              const struct ovs_key_ct_labels *mask)
 418 {
 419         struct nf_conn_labels *cl;
 420         int err;
 421
 422         cl = ovs_ct_get_conn_labels(ct);
 423         if (!cl)
 424                 return -ENOSPC;
 425
 426         err = nf_connlabels_replace(ct, labels->ct_labels_32,
 427                                     mask->ct_labels_32,
 428                                     OVS_CT_LABELS_LEN_32);
 429         if (err)
 430                 return err;
 431
 432         memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
 433
 434         return 0;
 435 }
 436
 437 /* 'skb' should already be pulled to nh_ofs. */
 438 static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
 439 {
 440         const struct nf_conntrack_helper *helper;
 441         const struct nf_conn_help *help;
 442         enum ip_conntrack_info ctinfo;
 443         unsigned int protoff;
 444         struct nf_conn *ct;
 445         int err;
 446
 447         ct = nf_ct_get(skb, &ctinfo);
 448         if (!ct || ctinfo == IP_CT_RELATED_REPLY)
 449                 return NF_ACCEPT;
 450
 451         help = nfct_help(ct);
 452         if (!help)
 453                 return NF_ACCEPT;
 454
 455         helper = rcu_dereference(help->helper);
 456         if (!helper)
 457                 return NF_ACCEPT;
 458
 459         switch (proto) {
 460         case NFPROTO_IPV4:
 461                 protoff = ip_hdrlen(skb);
 462                 break;
 463         case NFPROTO_IPV6: {
 464                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 465                 __be16 frag_off;
 466                 int ofs;
 467
 468                 ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
 469                                        &frag_off);
 470                 if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
 471                         pr_debug("proto header not found\n");
 472                         return NF_ACCEPT;
 473                 }
 474                 protoff = ofs;
 475                 break;
 476         }
 477         default:
 478                 WARN_ONCE(1, "helper invoked on non-IP family!");
 479                 return NF_DROP;
 480         }
 481
 482         err = helper->help(skb, protoff, ct, ctinfo);
 483         if (err != NF_ACCEPT)
 484                 return err;
 485
 486         /* Adjust seqs after helper.  This is needed due to some helpers (e.g.,
 487          * FTP with NAT) adusting the TCP payload size when mangling IP
 488          * addresses and/or port numbers in the text-based control connection.
 489          */
 490         if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
 491             !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
 492                 return NF_DROP;
 493         return NF_ACCEPT;
 494 }
 495
 496 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
 497  * value if 'skb' is freed.
 498  */
 499 static int handle_fragments(struct net *net, struct sw_flow_key *key,
 500                             u16 zone, struct sk_buff *skb)
 501 {
 502         struct ovs_skb_cb ovs_cb = *OVS_CB(skb);
 503         int err;
 504
 505         if (key->eth.type == htons(ETH_P_IP)) {
 506                 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
 507
 508                 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 509                 err = ip_defrag(net, skb, user);
 510                 if (err)
 511                         return err;
 512
 513                 ovs_cb.mru = IPCB(skb)->frag_max_size;
 514 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 515         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 516                 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
 517
 518                 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 519                 err = nf_ct_frag6_gather(net, skb, user);
 520                 if (err) {
 521                         if (err != -EINPROGRESS)
 522                                 kfree_skb(skb);
 523                         return err;
 524                 }
 525
 526                 key->ip.proto = ipv6_hdr(skb)->nexthdr;
 527                 ovs_cb.mru = IP6CB(skb)->frag_max_size;
 528 #endif
 529         } else {
 530                 kfree_skb(skb);
 531                 return -EPFNOSUPPORT;
 532         }
 533
 534         /* The key extracted from the fragment that completed this datagram
 535          * likely didn't have an L4 header, so regenerate it.
 536          */
 537         ovs_flow_key_update_l3l4(skb, key);
 538
 539         key->ip.frag = OVS_FRAG_TYPE_NONE;
 540         skb_clear_hash(skb);
 541         skb->ignore_df = 1;
 542         *OVS_CB(skb) = ovs_cb;
 543
 544         return 0;
 545 }
 546
 547 static struct nf_conntrack_expect *
 548 ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone,
 549                    u16 proto, const struct sk_buff *skb)
 550 {
 551         struct nf_conntrack_tuple tuple;
 552         struct nf_conntrack_expect *exp;
 553
 554         if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple))
 555                 return NULL;
 556
 557         exp = __nf_ct_expect_find(net, zone, &tuple);
 558         if (exp) {
 559                 struct nf_conntrack_tuple_hash *h;
 560
 561                 /* Delete existing conntrack entry, if it clashes with the
 562                  * expectation.  This can happen since conntrack ALGs do not
 563                  * check for clashes between (new) expectations and existing
 564                  * conntrack entries.  nf_conntrack_in() will check the
 565                  * expectations only if a conntrack entry can not be found,
 566                  * which can lead to OVS finding the expectation (here) in the
 567                  * init direction, but which will not be removed by the
 568                  * nf_conntrack_in() call, if a matching conntrack entry is
 569                  * found instead.  In this case all init direction packets
 570                  * would be reported as new related packets, while reply
 571                  * direction packets would be reported as un-related
 572                  * established packets.
 573                  */
 574                 h = nf_conntrack_find_get(net, zone, &tuple);
 575                 if (h) {
 576                         struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
 577
 578                         nf_ct_delete(ct, 0, 0);
 579                         nf_ct_put(ct);
 580                 }
 581         }
 582
 583         return exp;
 584 }
 585
 586 /* This replicates logic from nf_conntrack_core.c that is not exported. */
 587 static enum ip_conntrack_info
 588 ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h)
 589 {
 590         const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
 591
 592         if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
 593                 return IP_CT_ESTABLISHED_REPLY;
 594         /* Once we've had two way comms, always ESTABLISHED. */
 595         if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status))
 596                 return IP_CT_ESTABLISHED;
 597         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
 598                 return IP_CT_RELATED;
 599         return IP_CT_NEW;
 600 }
 601
 602 /* Find an existing connection which this packet belongs to without
 603  * re-attributing statistics or modifying the connection state.  This allows an
 604  * skb->_nfct lost due to an upcall to be recovered during actions execution.
 605  *
 606  * Must be called with rcu_read_lock.
 607  *
 608  * On success, populates skb->_nfct and returns the connection.  Returns NULL
 609  * if there is no existing entry.
 610  */
 611 static struct nf_conn *
 612 ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone,
 613                      u8 l3num, struct sk_buff *skb, bool natted)
 614 {
 615         struct nf_conntrack_tuple tuple;
 616         struct nf_conntrack_tuple_hash *h;
 617         struct nf_conn *ct;
 618
 619         if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), l3num,
 620                                net, &tuple)) {
 621                 pr_debug("ovs_ct_find_existing: Can't get tuple\n");
 622                 return NULL;
 623         }
 624
 625         /* Must invert the tuple if skb has been transformed by NAT. */
 626         if (natted) {
 627                 struct nf_conntrack_tuple inverse;
 628
 629                 if (!nf_ct_invert_tuple(&inverse, &tuple)) {
 630                         pr_debug("ovs_ct_find_existing: Inversion failed!\n");
 631                         return NULL;
 632                 }
 633                 tuple = inverse;
 634         }
 635
 636         /* look for tuple match */
 637         h = nf_conntrack_find_get(net, zone, &tuple);
 638         if (!h)
 639                 return NULL;   /* Not found. */
 640
 641         ct = nf_ct_tuplehash_to_ctrack(h);
 642
 643         /* Inverted packet tuple matches the reverse direction conntrack tuple,
 644          * select the other tuplehash to get the right 'ctinfo' bits for this
 645          * packet.
 646          */
 647         if (natted)
 648                 h = &ct->tuplehash[!h->tuple.dst.dir];
 649
 650         nf_ct_set(skb, ct, ovs_ct_get_info(h));
 651         return ct;
 652 }
 653
 654 static
 655 struct nf_conn *ovs_ct_executed(struct net *net,
 656                                 const struct sw_flow_key *key,
 657                                 const struct ovs_conntrack_info *info,
 658                                 struct sk_buff *skb,
 659                                 bool *ct_executed)
 660 {
 661         struct nf_conn *ct = NULL;
 662
 663         /* If no ct, check if we have evidence that an existing conntrack entry
 664          * might be found for this skb.  This happens when we lose a skb->_nfct
 665          * due to an upcall, or if the direction is being forced.  If the
 666          * connection was not confirmed, it is not cached and needs to be run
 667          * through conntrack again.
 668          */
 669         *ct_executed = (key->ct_state & OVS_CS_F_TRACKED) &&
 670                        !(key->ct_state & OVS_CS_F_INVALID) &&
 671                        (key->ct_zone == info->zone.id);
 672
 673         if (*ct_executed || (!key->ct_state && info->force)) {
 674                 ct = ovs_ct_find_existing(net, &info->zone, info->family, skb,
 675                                           !!(key->ct_state &
 676                                           OVS_CS_F_NAT_MASK));
 677         }
 678
 679         return ct;
 680 }
 681
 682 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
 683 static bool skb_nfct_cached(struct net *net,
 684                             const struct sw_flow_key *key,
 685                             const struct ovs_conntrack_info *info,
 686                             struct sk_buff *skb)
 687 {
 688         enum ip_conntrack_info ctinfo;
 689         struct nf_conn *ct;
 690         bool ct_executed = true;
 691
 692         ct = nf_ct_get(skb, &ctinfo);
 693         if (!ct)
 694                 ct = ovs_ct_executed(net, key, info, skb, &ct_executed);
 695
 696         if (ct)
 697                 nf_ct_get(skb, &ctinfo);
 698         else
 699                 return false;
 700
 701         if (!net_eq(net, read_pnet(&ct->ct_net)))
 702                 return false;
 703         if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct)))
 704                 return false;
 705         if (info->helper) {
 706                 struct nf_conn_help *help;
 707
 708                 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
 709                 if (help && rcu_access_pointer(help->helper) != info->helper)
 710                         return false;
 711         }
 712         if (info->nf_ct_timeout) {
 713                 struct nf_conn_timeout *timeout_ext;
 714
 715                 timeout_ext = nf_ct_timeout_find(ct);
 716                 if (!timeout_ext || info->nf_ct_timeout !=
 717                     rcu_dereference(timeout_ext->timeout))
 718                         return false;
 719         }
 720         /* Force conntrack entry direction to the current packet? */
 721         if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
 722                 /* Delete the conntrack entry if confirmed, else just release
 723                  * the reference.
 724                  */
 725                 if (nf_ct_is_confirmed(ct))
 726                         nf_ct_delete(ct, 0, 0);
 727
 728                 nf_ct_put(ct);
 729                 nf_ct_set(skb, NULL, 0);
 730                 return false;
 731         }
 732
 733         return ct_executed;
 734 }
 735
 736 #if IS_ENABLED(CONFIG_NF_NAT)
 737 static void ovs_nat_update_key(struct sw_flow_key *key,
 738                                const struct sk_buff *skb,
 739                                enum nf_nat_manip_type maniptype)
 740 {
 741         if (maniptype == NF_NAT_MANIP_SRC) {
 742                 __be16 src;
 743
 744                 key->ct_state |= OVS_CS_F_SRC_NAT;
 745                 if (key->eth.type == htons(ETH_P_IP))
 746                         key->ipv4.addr.src = ip_hdr(skb)->saddr;
 747                 else if (key->eth.type == htons(ETH_P_IPV6))
 748                         memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
 749                                sizeof(key->ipv6.addr.src));
 750                 else
 751                         return;
 752
 753                 if (key->ip.proto == IPPROTO_UDP)
 754                         src = udp_hdr(skb)->source;
 755                 else if (key->ip.proto == IPPROTO_TCP)
 756                         src = tcp_hdr(skb)->source;
 757                 else if (key->ip.proto == IPPROTO_SCTP)
 758                         src = sctp_hdr(skb)->source;
 759                 else
 760                         return;
 761
 762                 key->tp.src = src;
 763         } else {
 764                 __be16 dst;
 765
 766                 key->ct_state |= OVS_CS_F_DST_NAT;
 767                 if (key->eth.type == htons(ETH_P_IP))
 768                         key->ipv4.addr.dst = ip_hdr(skb)->daddr;
 769                 else if (key->eth.type == htons(ETH_P_IPV6))
 770                         memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
 771                                sizeof(key->ipv6.addr.dst));
 772                 else
 773                         return;
 774
 775                 if (key->ip.proto == IPPROTO_UDP)
 776                         dst = udp_hdr(skb)->dest;
 777                 else if (key->ip.proto == IPPROTO_TCP)
 778                         dst = tcp_hdr(skb)->dest;
 779                 else if (key->ip.proto == IPPROTO_SCTP)
 780                         dst = sctp_hdr(skb)->dest;
 781                 else
 782                         return;
 783
 784                 key->tp.dst = dst;
 785         }
 786 }
 787
 788 /* Modelled after nf_nat_ipv[46]_fn().
 789  * range is only used for new, uninitialized NAT state.
 790  * Returns either NF_ACCEPT or NF_DROP.
 791  */
 792 static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 793                               enum ip_conntrack_info ctinfo,
 794                               const struct nf_nat_range2 *range,
 795                               enum nf_nat_manip_type maniptype, struct sw_flow_key *key)
 796 {
 797         int hooknum, nh_off, err = NF_ACCEPT;
 798
 799         nh_off = skb_network_offset(skb);
 800         skb_pull_rcsum(skb, nh_off);
 801
 802         /* See HOOK2MANIP(). */
 803         if (maniptype == NF_NAT_MANIP_SRC)
 804                 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
 805         else
 806                 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
 807
 808         switch (ctinfo) {
 809         case IP_CT_RELATED:
 810         case IP_CT_RELATED_REPLY:
 811                 if (IS_ENABLED(CONFIG_NF_NAT) &&
 812                     skb->protocol == htons(ETH_P_IP) &&
 813                     ip_hdr(skb)->protocol == IPPROTO_ICMP) {
 814                         if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
 815                                                            hooknum))
 816                                 err = NF_DROP;
 817                         goto push;
 818                 } else if (IS_ENABLED(CONFIG_IPV6) &&
 819                            skb->protocol == htons(ETH_P_IPV6)) {
 820                         __be16 frag_off;
 821                         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 822                         int hdrlen = ipv6_skip_exthdr(skb,
 823                                                       sizeof(struct ipv6hdr),
 824                                                       &nexthdr, &frag_off);
 825
 826                         if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
 827                                 if (!nf_nat_icmpv6_reply_translation(skb, ct,
 828                                                                      ctinfo,
 829                                                                      hooknum,
 830                                                                      hdrlen))
 831                                         err = NF_DROP;
 832                                 goto push;
 833                         }
 834                 }
 835                 /* Non-ICMP, fall thru to initialize if needed. */
 836                 fallthrough;
 837         case IP_CT_NEW:
 838                 /* Seen it before?  This can happen for loopback, retrans,
 839                  * or local packets.
 840                  */
 841                 if (!nf_nat_initialized(ct, maniptype)) {
 842                         /* Initialize according to the NAT action. */
 843                         err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
 844                                 /* Action is set up to establish a new
 845                                  * mapping.
 846                                  */
 847                                 ? nf_nat_setup_info(ct, range, maniptype)
 848                                 : nf_nat_alloc_null_binding(ct, hooknum);
 849                         if (err != NF_ACCEPT)
 850                                 goto push;
 851                 }
 852                 break;
 853
 854         case IP_CT_ESTABLISHED:
 855         case IP_CT_ESTABLISHED_REPLY:
 856                 break;
 857
 858         default:
 859                 err = NF_DROP;
 860                 goto push;
 861         }
 862
 863         err = nf_nat_packet(ct, ctinfo, hooknum, skb);
 864 push:
 865         skb_push_rcsum(skb, nh_off);
 866
 867         /* Update the flow key if NAT successful. */
 868         if (err == NF_ACCEPT)
 869                 ovs_nat_update_key(key, skb, maniptype);
 870
 871         return err;
 872 }
 873
 874 /* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
 875 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
 876                       const struct ovs_conntrack_info *info,
 877                       struct sk_buff *skb, struct nf_conn *ct,
 878                       enum ip_conntrack_info ctinfo)
 879 {
 880         enum nf_nat_manip_type maniptype;
 881         int err;
 882
 883         /* Add NAT extension if not confirmed yet. */
 884         if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
 885                 return NF_ACCEPT;   /* Can't NAT. */
 886
 887         /* Determine NAT type.
 888          * Check if the NAT type can be deduced from the tracked connection.
 889          * Make sure new expected connections (IP_CT_RELATED) are NATted only
 890          * when committing.
 891          */
 892         if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
 893             ct->status & IPS_NAT_MASK &&
 894             (ctinfo != IP_CT_RELATED || info->commit)) {
 895                 /* NAT an established or related connection like before. */
 896                 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
 897                         /* This is the REPLY direction for a connection
 898                          * for which NAT was applied in the forward
 899                          * direction.  Do the reverse NAT.
 900                          */
 901                         maniptype = ct->status & IPS_SRC_NAT
 902                                 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
 903                 else
 904                         maniptype = ct->status & IPS_SRC_NAT
 905                                 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
 906         } else if (info->nat & OVS_CT_SRC_NAT) {
 907                 maniptype = NF_NAT_MANIP_SRC;
 908         } else if (info->nat & OVS_CT_DST_NAT) {
 909                 maniptype = NF_NAT_MANIP_DST;
 910         } else {
 911                 return NF_ACCEPT; /* Connection is not NATed. */
 912         }
 913         err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype, key);
 914
 915         if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) {
 916                 if (ct->status & IPS_SRC_NAT) {
 917                         if (maniptype == NF_NAT_MANIP_SRC)
 918                                 maniptype = NF_NAT_MANIP_DST;
 919                         else
 920                                 maniptype = NF_NAT_MANIP_SRC;
 921
 922                         err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range,
 923                                                  maniptype, key);
 924                 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) {
 925                         err = ovs_ct_nat_execute(skb, ct, ctinfo, NULL,
 926                                                  NF_NAT_MANIP_SRC, key);
 927                 }
 928         }
 929
 930         return err;
 931 }
 932 #else /* !CONFIG_NF_NAT */
 933 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
 934                       const struct ovs_conntrack_info *info,
 935                       struct sk_buff *skb, struct nf_conn *ct,
 936                       enum ip_conntrack_info ctinfo)
 937 {
 938         return NF_ACCEPT;
 939 }
 940 #endif
 941
 942 /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
 943  * not done already.  Update key with new CT state after passing the packet
 944  * through conntrack.
 945  * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be
 946  * set to NULL and 0 will be returned.
 947  */
 948 static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 949                            const struct ovs_conntrack_info *info,
 950                            struct sk_buff *skb)
 951 {
 952         /* If we are recirculating packets to match on conntrack fields and
 953          * committing with a separate conntrack action,  then we don't need to
 954          * actually run the packet through conntrack twice unless it's for a
 955          * different zone.
 956          */
 957         bool cached = skb_nfct_cached(net, key, info, skb);
 958         enum ip_conntrack_info ctinfo;
 959         struct nf_conn *ct;
 960
 961         if (!cached) {
 962                 struct nf_hook_state state = {
 963                         .hook = NF_INET_PRE_ROUTING,
 964                         .pf = info->family,
 965                         .net = net,
 966                 };
 967                 struct nf_conn *tmpl = info->ct;
 968                 int err;
 969
 970                 /* Associate skb with specified zone. */
 971                 if (tmpl) {
 972                         ct = nf_ct_get(skb, &ctinfo);
 973                         nf_ct_put(ct);
 974                         nf_conntrack_get(&tmpl->ct_general);
 975                         nf_ct_set(skb, tmpl, IP_CT_NEW);
 976                 }
 977
 978                 err = nf_conntrack_in(skb, &state);
 979                 if (err != NF_ACCEPT)
 980                         return -ENOENT;
 981
 982                 /* Clear CT state NAT flags to mark that we have not yet done
 983                  * NAT after the nf_conntrack_in() call.  We can actually clear
 984                  * the whole state, as it will be re-initialized below.
 985                  */
 986                 key->ct_state = 0;
 987
 988                 /* Update the key, but keep the NAT flags. */
 989                 ovs_ct_update_key(skb, info, key, true, true);
 990         }
 991
 992         ct = nf_ct_get(skb, &ctinfo);
 993         if (ct) {
 994                 bool add_helper = false;
 995
 996                 /* Packets starting a new connection must be NATted before the
 997                  * helper, so that the helper knows about the NAT.  We enforce
 998                  * this by delaying both NAT and helper calls for unconfirmed
 999                  * connections until the committing CT action.  For later
1000                  * packets NAT and Helper may be called in either order.
1001                  *
1002                  * NAT will be done only if the CT action has NAT, and only
1003                  * once per packet (per zone), as guarded by the NAT bits in
1004                  * the key->ct_state.
1005                  */
1006                 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) &&
1007                     (nf_ct_is_confirmed(ct) || info->commit) &&
1008                     ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
1009                         return -EINVAL;
1010                 }
1011
1012                 /* Userspace may decide to perform a ct lookup without a helper
1013                  * specified followed by a (recirculate and) commit with one,
1014                  * or attach a helper in a later commit.  Therefore, for
1015                  * connections which we will commit, we may need to attach
1016                  * the helper here.
1017                  */
1018                 if (!nf_ct_is_confirmed(ct) && info->commit &&
1019                     info->helper && !nfct_help(ct)) {
1020                         int err = __nf_ct_try_assign_helper(ct, info->ct,
1021                                                             GFP_ATOMIC);
1022                         if (err)
1023                                 return err;
1024                         add_helper = true;
1025
1026                         /* helper installed, add seqadj if NAT is required */
1027                         if (info->nat && !nfct_seqadj(ct)) {
1028                                 if (!nfct_seqadj_ext_add(ct))
1029                                         return -EINVAL;
1030                         }
1031                 }
1032
1033                 /* Call the helper only if:
1034                  * - nf_conntrack_in() was executed above ("!cached") or a
1035                  *   helper was just attached ("add_helper") for a confirmed
1036                  *   connection, or
1037                  * - When committing an unconfirmed connection.
1038                  */
1039                 if ((nf_ct_is_confirmed(ct) ? !cached || add_helper :
1040                                               info->commit) &&
1041                     ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
1042                         return -EINVAL;
1043                 }
1044
1045                 if (nf_ct_protonum(ct) == IPPROTO_TCP &&
1046                     nf_ct_is_confirmed(ct) && nf_conntrack_tcp_established(ct)) {
1047                         /* Be liberal for tcp packets so that out-of-window
1048                          * packets are not marked invalid.
1049                          */
1050                         nf_ct_set_tcp_be_liberal(ct);
1051                 }
1052
1053                 nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1054         }
1055
1056         return 0;
1057 }
1058
1059 /* Lookup connection and read fields into key. */
1060 static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
1061                          const struct ovs_conntrack_info *info,
1062                          struct sk_buff *skb)
1063 {
1064         struct nf_conntrack_expect *exp;
1065
1066         /* If we pass an expected packet through nf_conntrack_in() the
1067          * expectation is typically removed, but the packet could still be
1068          * lost in upcall processing.  To prevent this from happening we
1069          * perform an explicit expectation lookup.  Expected connections are
1070          * always new, and will be passed through conntrack only when they are
1071          * committed, as it is OK to remove the expectation at that time.
1072          */
1073         exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
1074         if (exp) {
1075                 u8 state;
1076
1077                 /* NOTE: New connections are NATted and Helped only when
1078                  * committed, so we are not calling into NAT here.
1079                  */
1080                 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
1081                 __ovs_ct_update_key(key, state, &info->zone, exp->master);
1082         } else {
1083                 struct nf_conn *ct;
1084                 int err;
1085
1086                 err = __ovs_ct_lookup(net, key, info, skb);
1087                 if (err)
1088                         return err;
1089
1090                 ct = (struct nf_conn *)skb_nfct(skb);
1091                 if (ct)
1092                         nf_ct_deliver_cached_events(ct);
1093         }
1094
1095         return 0;
1096 }
1097
1098 static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
1099 {
1100         size_t i;
1101
1102         for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
1103                 if (labels->ct_labels_32[i])
1104                         return true;
1105
1106         return false;
1107 }
1108
1109 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1110 static struct hlist_head *ct_limit_hash_bucket(
1111         const struct ovs_ct_limit_info *info, u16 zone)
1112 {
1113         return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)];
1114 }
1115
1116 /* Call with ovs_mutex */
1117 static void ct_limit_set(const struct ovs_ct_limit_info *info,
1118                          struct ovs_ct_limit *new_ct_limit)
1119 {
1120         struct ovs_ct_limit *ct_limit;
1121         struct hlist_head *head;
1122
1123         head = ct_limit_hash_bucket(info, new_ct_limit->zone);
1124         hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1125                 if (ct_limit->zone == new_ct_limit->zone) {
1126                         hlist_replace_rcu(&ct_limit->hlist_node,
1127                                           &new_ct_limit->hlist_node);
1128                         kfree_rcu(ct_limit, rcu);
1129                         return;
1130                 }
1131         }
1132
1133         hlist_add_head_rcu(&new_ct_limit->hlist_node, head);
1134 }
1135
1136 /* Call with ovs_mutex */
1137 static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone)
1138 {
1139         struct ovs_ct_limit *ct_limit;
1140         struct hlist_head *head;
1141         struct hlist_node *n;
1142
1143         head = ct_limit_hash_bucket(info, zone);
1144         hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) {
1145                 if (ct_limit->zone == zone) {
1146                         hlist_del_rcu(&ct_limit->hlist_node);
1147                         kfree_rcu(ct_limit, rcu);
1148                         return;
1149                 }
1150         }
1151 }
1152
1153 /* Call with RCU read lock */
1154 static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone)
1155 {
1156         struct ovs_ct_limit *ct_limit;
1157         struct hlist_head *head;
1158
1159         head = ct_limit_hash_bucket(info, zone);
1160         hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1161                 if (ct_limit->zone == zone)
1162                         return ct_limit->limit;
1163         }
1164
1165         return info->default_limit;
1166 }
1167
1168 static int ovs_ct_check_limit(struct net *net,
1169                               const struct ovs_conntrack_info *info,
1170                               const struct nf_conntrack_tuple *tuple)
1171 {
1172         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1173         const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
1174         u32 per_zone_limit, connections;
1175         u32 conncount_key;
1176
1177         conncount_key = info->zone.id;
1178
1179         per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id);
1180         if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED)
1181                 return 0;
1182
1183         connections = nf_conncount_count(net, ct_limit_info->data,
1184                                          &conncount_key, tuple, &info->zone);
1185         if (connections > per_zone_limit)
1186                 return -ENOMEM;
1187
1188         return 0;
1189 }
1190 #endif
1191
1192 /* Lookup connection and confirm if unconfirmed. */
1193 static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
1194                          const struct ovs_conntrack_info *info,
1195                          struct sk_buff *skb)
1196 {
1197         enum ip_conntrack_info ctinfo;
1198         struct nf_conn *ct;
1199         int err;
1200
1201         err = __ovs_ct_lookup(net, key, info, skb);
1202         if (err)
1203                 return err;
1204
1205         /* The connection could be invalid, in which case this is a no-op.*/
1206         ct = nf_ct_get(skb, &ctinfo);
1207         if (!ct)
1208                 return 0;
1209
1210 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1211         if (static_branch_unlikely(&ovs_ct_limit_enabled)) {
1212                 if (!nf_ct_is_confirmed(ct)) {
1213                         err = ovs_ct_check_limit(net, info,
1214                                 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
1215                         if (err) {
1216                                 net_warn_ratelimited("openvswitch: zone: %u "
1217                                         "exceeds conntrack limit\n",
1218                                         info->zone.id);
1219                                 return err;
1220                         }
1221                 }
1222         }
1223 #endif
1224
1225         /* Set the conntrack event mask if given.  NEW and DELETE events have
1226          * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
1227          * typically would receive many kinds of updates.  Setting the event
1228          * mask allows those events to be filtered.  The set event mask will
1229          * remain in effect for the lifetime of the connection unless changed
1230          * by a further CT action with both the commit flag and the eventmask
1231          * option. */
1232         if (info->have_eventmask) {
1233                 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct);
1234
1235                 if (cache)
1236                         cache->ctmask = info->eventmask;
1237         }
1238
1239         /* Apply changes before confirming the connection so that the initial
1240          * conntrack NEW netlink event carries the values given in the CT
1241          * action.
1242          */
1243         if (info->mark.mask) {
1244                 err = ovs_ct_set_mark(ct, key, info->mark.value,
1245                                       info->mark.mask);
1246                 if (err)
1247                         return err;
1248         }
1249         if (!nf_ct_is_confirmed(ct)) {
1250                 err = ovs_ct_init_labels(ct, key, &info->labels.value,
1251                                          &info->labels.mask);
1252                 if (err)
1253                         return err;
1254
1255                 nf_conn_act_ct_ext_add(skb, ct, ctinfo);
1256         } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1257                    labels_nonzero(&info->labels.mask)) {
1258                 err = ovs_ct_set_labels(ct, key, &info->labels.value,
1259                                         &info->labels.mask);
1260                 if (err)
1261                         return err;
1262         }
1263         /* This will take care of sending queued events even if the connection
1264          * is already confirmed.
1265          */
1266         if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1267                 return -EINVAL;
1268
1269         return 0;
1270 }
1271
1272 /* Trim the skb to the length specified by the IP/IPv6 header,
1273  * removing any trailing lower-layer padding. This prepares the skb
1274  * for higher-layer processing that assumes skb->len excludes padding
1275  * (such as nf_ip_checksum). The caller needs to pull the skb to the
1276  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
1277  */
1278 static int ovs_skb_network_trim(struct sk_buff *skb)
1279 {
1280         unsigned int len;
1281         int err;
1282
1283         switch (skb->protocol) {
1284         case htons(ETH_P_IP):
1285                 len = ntohs(ip_hdr(skb)->tot_len);
1286                 break;
1287         case htons(ETH_P_IPV6):
1288                 len = sizeof(struct ipv6hdr)
1289                         + ntohs(ipv6_hdr(skb)->payload_len);
1290                 break;
1291         default:
1292                 len = skb->len;
1293         }
1294
1295         err = pskb_trim_rcsum(skb, len);
1296         if (err)
1297                 kfree_skb(skb);
1298
1299         return err;
1300 }
1301
1302 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
1303  * value if 'skb' is freed.
1304  */
1305 int ovs_ct_execute(struct net *net, struct sk_buff *skb,
1306                    struct sw_flow_key *key,
1307                    const struct ovs_conntrack_info *info)
1308 {
1309         int nh_ofs;
1310         int err;
1311
1312         /* The conntrack module expects to be working at L3. */
1313         nh_ofs = skb_network_offset(skb);
1314         skb_pull_rcsum(skb, nh_ofs);
1315
1316         err = ovs_skb_network_trim(skb);
1317         if (err)
1318                 return err;
1319
1320         if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
1321                 err = handle_fragments(net, key, info->zone.id, skb);
1322                 if (err)
1323                         return err;
1324         }
1325
1326         if (info->commit)
1327                 err = ovs_ct_commit(net, key, info, skb);
1328         else
1329                 err = ovs_ct_lookup(net, key, info, skb);
1330
1331         skb_push_rcsum(skb, nh_ofs);
1332         if (err)
1333                 kfree_skb(skb);
1334         return err;
1335 }
1336
1337 int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key)
1338 {
1339         enum ip_conntrack_info ctinfo;
1340         struct nf_conn *ct;
1341
1342         ct = nf_ct_get(skb, &ctinfo);
1343
1344         nf_ct_put(ct);
1345         nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1346
1347         if (key)
1348                 ovs_ct_fill_key(skb, key, false);
1349
1350         return 0;
1351 }
1352
1353 static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
1354                              const struct sw_flow_key *key, bool log)
1355 {
1356         struct nf_conntrack_helper *helper;
1357         struct nf_conn_help *help;
1358         int ret = 0;
1359
1360         helper = nf_conntrack_helper_try_module_get(name, info->family,
1361                                                     key->ip.proto);
1362         if (!helper) {
1363                 OVS_NLERR(log, "Unknown helper \"%s\"", name);
1364                 return -EINVAL;
1365         }
1366
1367         help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL);
1368         if (!help) {
1369                 nf_conntrack_helper_put(helper);
1370                 return -ENOMEM;
1371         }
1372
1373 #if IS_ENABLED(CONFIG_NF_NAT)
1374         if (info->nat) {
1375                 ret = nf_nat_helper_try_module_get(name, info->family,
1376                                                    key->ip.proto);
1377                 if (ret) {
1378                         nf_conntrack_helper_put(helper);
1379                         OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d",
1380                                   name, ret);
1381                         return ret;
1382                 }
1383         }
1384 #endif
1385         rcu_assign_pointer(help->helper, helper);
1386         info->helper = helper;
1387         return ret;
1388 }
1389
1390 #if IS_ENABLED(CONFIG_NF_NAT)
1391 static int parse_nat(const struct nlattr *attr,
1392                      struct ovs_conntrack_info *info, bool log)
1393 {
1394         struct nlattr *a;
1395         int rem;
1396         bool have_ip_max = false;
1397         bool have_proto_max = false;
1398         bool ip_vers = (info->family == NFPROTO_IPV6);
1399
1400         nla_for_each_nested(a, attr, rem) {
1401                 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
1402                         [OVS_NAT_ATTR_SRC] = {0, 0},
1403                         [OVS_NAT_ATTR_DST] = {0, 0},
1404                         [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
1405                                                  sizeof(struct in6_addr)},
1406                         [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
1407                                                  sizeof(struct in6_addr)},
1408                         [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
1409                         [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
1410                         [OVS_NAT_ATTR_PERSISTENT] = {0, 0},
1411                         [OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
1412                         [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
1413                 };
1414                 int type = nla_type(a);
1415
1416                 if (type > OVS_NAT_ATTR_MAX) {
1417                         OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)",
1418                                   type, OVS_NAT_ATTR_MAX);
1419                         return -EINVAL;
1420                 }
1421
1422                 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
1423                         OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)",
1424                                   type, nla_len(a),
1425                                   ovs_nat_attr_lens[type][ip_vers]);
1426                         return -EINVAL;
1427                 }
1428
1429                 switch (type) {
1430                 case OVS_NAT_ATTR_SRC:
1431                 case OVS_NAT_ATTR_DST:
1432                         if (info->nat) {
1433                                 OVS_NLERR(log, "Only one type of NAT may be specified");
1434                                 return -ERANGE;
1435                         }
1436                         info->nat |= OVS_CT_NAT;
1437                         info->nat |= ((type == OVS_NAT_ATTR_SRC)
1438                                         ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
1439                         break;
1440
1441                 case OVS_NAT_ATTR_IP_MIN:
1442                         nla_memcpy(&info->range.min_addr, a,
1443                                    sizeof(info->range.min_addr));
1444                         info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1445                         break;
1446
1447                 case OVS_NAT_ATTR_IP_MAX:
1448                         have_ip_max = true;
1449                         nla_memcpy(&info->range.max_addr, a,
1450                                    sizeof(info->range.max_addr));
1451                         info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1452                         break;
1453
1454                 case OVS_NAT_ATTR_PROTO_MIN:
1455                         info->range.min_proto.all = htons(nla_get_u16(a));
1456                         info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1457                         break;
1458
1459                 case OVS_NAT_ATTR_PROTO_MAX:
1460                         have_proto_max = true;
1461                         info->range.max_proto.all = htons(nla_get_u16(a));
1462                         info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1463                         break;
1464
1465                 case OVS_NAT_ATTR_PERSISTENT:
1466                         info->range.flags |= NF_NAT_RANGE_PERSISTENT;
1467                         break;
1468
1469                 case OVS_NAT_ATTR_PROTO_HASH:
1470                         info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
1471                         break;
1472
1473                 case OVS_NAT_ATTR_PROTO_RANDOM:
1474                         info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
1475                         break;
1476
1477                 default:
1478                         OVS_NLERR(log, "Unknown nat attribute (%d)", type);
1479                         return -EINVAL;
1480                 }
1481         }
1482
1483         if (rem > 0) {
1484                 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem);
1485                 return -EINVAL;
1486         }
1487         if (!info->nat) {
1488                 /* Do not allow flags if no type is given. */
1489                 if (info->range.flags) {
1490                         OVS_NLERR(log,
1491                                   "NAT flags may be given only when NAT range (SRC or DST) is also specified."
1492                                   );
1493                         return -EINVAL;
1494                 }
1495                 info->nat = OVS_CT_NAT;   /* NAT existing connections. */
1496         } else if (!info->commit) {
1497                 OVS_NLERR(log,
1498                           "NAT attributes may be specified only when CT COMMIT flag is also specified."
1499                           );
1500                 return -EINVAL;
1501         }
1502         /* Allow missing IP_MAX. */
1503         if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
1504                 memcpy(&info->range.max_addr, &info->range.min_addr,
1505                        sizeof(info->range.max_addr));
1506         }
1507         /* Allow missing PROTO_MAX. */
1508         if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1509             !have_proto_max) {
1510                 info->range.max_proto.all = info->range.min_proto.all;
1511         }
1512         return 0;
1513 }
1514 #endif
1515
1516 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
1517         [OVS_CT_ATTR_COMMIT]    = { .minlen = 0, .maxlen = 0 },
1518         [OVS_CT_ATTR_FORCE_COMMIT]      = { .minlen = 0, .maxlen = 0 },
1519         [OVS_CT_ATTR_ZONE]      = { .minlen = sizeof(u16),
1520                                     .maxlen = sizeof(u16) },
1521         [OVS_CT_ATTR_MARK]      = { .minlen = sizeof(struct md_mark),
1522                                     .maxlen = sizeof(struct md_mark) },
1523         [OVS_CT_ATTR_LABELS]    = { .minlen = sizeof(struct md_labels),
1524                                     .maxlen = sizeof(struct md_labels) },
1525         [OVS_CT_ATTR_HELPER]    = { .minlen = 1,
1526                                     .maxlen = NF_CT_HELPER_NAME_LEN },
1527 #if IS_ENABLED(CONFIG_NF_NAT)
1528         /* NAT length is checked when parsing the nested attributes. */
1529         [OVS_CT_ATTR_NAT]       = { .minlen = 0, .maxlen = INT_MAX },
1530 #endif
1531         [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32),
1532                                     .maxlen = sizeof(u32) },
1533         [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1,
1534                                   .maxlen = CTNL_TIMEOUT_NAME_MAX },
1535 };
1536
1537 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
1538                     const char **helper, bool log)
1539 {
1540         struct nlattr *a;
1541         int rem;
1542
1543         nla_for_each_nested(a, attr, rem) {
1544                 int type = nla_type(a);
1545                 int maxlen;
1546                 int minlen;
1547
1548                 if (type > OVS_CT_ATTR_MAX) {
1549                         OVS_NLERR(log,
1550                                   "Unknown conntrack attr (type=%d, max=%d)",
1551                                   type, OVS_CT_ATTR_MAX);
1552                         return -EINVAL;
1553                 }
1554
1555                 maxlen = ovs_ct_attr_lens[type].maxlen;
1556                 minlen = ovs_ct_attr_lens[type].minlen;
1557                 if (nla_len(a) < minlen || nla_len(a) > maxlen) {
1558                         OVS_NLERR(log,
1559                                   "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
1560                                   type, nla_len(a), maxlen);
1561                         return -EINVAL;
1562                 }
1563
1564                 switch (type) {
1565                 case OVS_CT_ATTR_FORCE_COMMIT:
1566                         info->force = true;
1567                         fallthrough;
1568                 case OVS_CT_ATTR_COMMIT:
1569                         info->commit = true;
1570                         break;
1571 #ifdef CONFIG_NF_CONNTRACK_ZONES
1572                 case OVS_CT_ATTR_ZONE:
1573                         info->zone.id = nla_get_u16(a);
1574                         break;
1575 #endif
1576 #ifdef CONFIG_NF_CONNTRACK_MARK
1577                 case OVS_CT_ATTR_MARK: {
1578                         struct md_mark *mark = nla_data(a);
1579
1580                         if (!mark->mask) {
1581                                 OVS_NLERR(log, "ct_mark mask cannot be 0");
1582                                 return -EINVAL;
1583                         }
1584                         info->mark = *mark;
1585                         break;
1586                 }
1587 #endif
1588 #ifdef CONFIG_NF_CONNTRACK_LABELS
1589                 case OVS_CT_ATTR_LABELS: {
1590                         struct md_labels *labels = nla_data(a);
1591
1592                         if (!labels_nonzero(&labels->mask)) {
1593                                 OVS_NLERR(log, "ct_labels mask cannot be 0");
1594                                 return -EINVAL;
1595                         }
1596                         info->labels = *labels;
1597                         break;
1598                 }
1599 #endif
1600                 case OVS_CT_ATTR_HELPER:
1601                         *helper = nla_data(a);
1602                         if (!memchr(*helper, '\0', nla_len(a))) {
1603                                 OVS_NLERR(log, "Invalid conntrack helper");
1604                                 return -EINVAL;
1605                         }
1606                         break;
1607 #if IS_ENABLED(CONFIG_NF_NAT)
1608                 case OVS_CT_ATTR_NAT: {
1609                         int err = parse_nat(a, info, log);
1610
1611                         if (err)
1612                                 return err;
1613                         break;
1614                 }
1615 #endif
1616                 case OVS_CT_ATTR_EVENTMASK:
1617                         info->have_eventmask = true;
1618                         info->eventmask = nla_get_u32(a);
1619                         break;
1620 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1621                 case OVS_CT_ATTR_TIMEOUT:
1622                         memcpy(info->timeout, nla_data(a), nla_len(a));
1623                         if (!memchr(info->timeout, '\0', nla_len(a))) {
1624                                 OVS_NLERR(log, "Invalid conntrack timeout");
1625                                 return -EINVAL;
1626                         }
1627                         break;
1628 #endif
1629
1630                 default:
1631                         OVS_NLERR(log, "Unknown conntrack attr (%d)",
1632                                   type);
1633                         return -EINVAL;
1634                 }
1635         }
1636
1637 #ifdef CONFIG_NF_CONNTRACK_MARK
1638         if (!info->commit && info->mark.mask) {
1639                 OVS_NLERR(log,
1640                           "Setting conntrack mark requires 'commit' flag.");
1641                 return -EINVAL;
1642         }
1643 #endif
1644 #ifdef CONFIG_NF_CONNTRACK_LABELS
1645         if (!info->commit && labels_nonzero(&info->labels.mask)) {
1646                 OVS_NLERR(log,
1647                           "Setting conntrack labels requires 'commit' flag.");
1648                 return -EINVAL;
1649         }
1650 #endif
1651         if (rem > 0) {
1652                 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
1653                 return -EINVAL;
1654         }
1655
1656         return 0;
1657 }
1658
1659 bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
1660 {
1661         if (attr == OVS_KEY_ATTR_CT_STATE)
1662                 return true;
1663         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1664             attr == OVS_KEY_ATTR_CT_ZONE)
1665                 return true;
1666         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1667             attr == OVS_KEY_ATTR_CT_MARK)
1668                 return true;
1669         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1670             attr == OVS_KEY_ATTR_CT_LABELS) {
1671                 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1672
1673                 return ovs_net->xt_label;
1674         }
1675
1676         return false;
1677 }
1678
1679 int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
1680                        const struct sw_flow_key *key,
1681                        struct sw_flow_actions **sfa,  bool log)
1682 {
1683         struct ovs_conntrack_info ct_info;
1684         const char *helper = NULL;
1685         u16 family;
1686         int err;
1687
1688         family = key_to_nfproto(key);
1689         if (family == NFPROTO_UNSPEC) {
1690                 OVS_NLERR(log, "ct family unspecified");
1691                 return -EINVAL;
1692         }
1693
1694         memset(&ct_info, 0, sizeof(ct_info));
1695         ct_info.family = family;
1696
1697         nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
1698                         NF_CT_DEFAULT_ZONE_DIR, 0);
1699
1700         err = parse_ct(attr, &ct_info, &helper, log);
1701         if (err)
1702                 return err;
1703
1704         /* Set up template for tracking connections in specific zones. */
1705         ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
1706         if (!ct_info.ct) {
1707                 OVS_NLERR(log, "Failed to allocate conntrack template");
1708                 return -ENOMEM;
1709         }
1710
1711         if (ct_info.timeout[0]) {
1712                 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto,
1713                                       ct_info.timeout))
1714                         OVS_NLERR(log,
1715                                   "Failed to associated timeout policy '%s'",
1716                                   ct_info.timeout);
1717                 else
1718                         ct_info.nf_ct_timeout = rcu_dereference(
1719                                 nf_ct_timeout_find(ct_info.ct)->timeout);
1720
1721         }
1722
1723         if (helper) {
1724                 err = ovs_ct_add_helper(&ct_info, helper, key, log);
1725                 if (err)
1726                         goto err_free_ct;
1727         }
1728
1729         err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
1730                                  sizeof(ct_info), log);
1731         if (err)
1732                 goto err_free_ct;
1733
1734         __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
1735         return 0;
1736 err_free_ct:
1737         __ovs_ct_free_action(&ct_info);
1738         return err;
1739 }
1740
1741 #if IS_ENABLED(CONFIG_NF_NAT)
1742 static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
1743                                struct sk_buff *skb)
1744 {
1745         struct nlattr *start;
1746
1747         start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT);
1748         if (!start)
1749                 return false;
1750
1751         if (info->nat & OVS_CT_SRC_NAT) {
1752                 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
1753                         return false;
1754         } else if (info->nat & OVS_CT_DST_NAT) {
1755                 if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
1756                         return false;
1757         } else {
1758                 goto out;
1759         }
1760
1761         if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
1762                 if (IS_ENABLED(CONFIG_NF_NAT) &&
1763                     info->family == NFPROTO_IPV4) {
1764                         if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
1765                                             info->range.min_addr.ip) ||
1766                             (info->range.max_addr.ip
1767                              != info->range.min_addr.ip &&
1768                              (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
1769                                               info->range.max_addr.ip))))
1770                                 return false;
1771                 } else if (IS_ENABLED(CONFIG_IPV6) &&
1772                            info->family == NFPROTO_IPV6) {
1773                         if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
1774                                              &info->range.min_addr.in6) ||
1775                             (memcmp(&info->range.max_addr.in6,
1776                                     &info->range.min_addr.in6,
1777                                     sizeof(info->range.max_addr.in6)) &&
1778                              (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
1779                                                &info->range.max_addr.in6))))
1780                                 return false;
1781                 } else {
1782                         return false;
1783                 }
1784         }
1785         if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1786             (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
1787                          ntohs(info->range.min_proto.all)) ||
1788              (info->range.max_proto.all != info->range.min_proto.all &&
1789               nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
1790                           ntohs(info->range.max_proto.all)))))
1791                 return false;
1792
1793         if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
1794             nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
1795                 return false;
1796         if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
1797             nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
1798                 return false;
1799         if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
1800             nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
1801                 return false;
1802 out:
1803         nla_nest_end(skb, start);
1804
1805         return true;
1806 }
1807 #endif
1808
1809 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
1810                           struct sk_buff *skb)
1811 {
1812         struct nlattr *start;
1813
1814         start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT);
1815         if (!start)
1816                 return -EMSGSIZE;
1817
1818         if (ct_info->commit && nla_put_flag(skb, ct_info->force
1819                                             ? OVS_CT_ATTR_FORCE_COMMIT
1820                                             : OVS_CT_ATTR_COMMIT))
1821                 return -EMSGSIZE;
1822         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1823             nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
1824                 return -EMSGSIZE;
1825         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
1826             nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
1827                     &ct_info->mark))
1828                 return -EMSGSIZE;
1829         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1830             labels_nonzero(&ct_info->labels.mask) &&
1831             nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
1832                     &ct_info->labels))
1833                 return -EMSGSIZE;
1834         if (ct_info->helper) {
1835                 if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
1836                                    ct_info->helper->name))
1837                         return -EMSGSIZE;
1838         }
1839         if (ct_info->have_eventmask &&
1840             nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask))
1841                 return -EMSGSIZE;
1842         if (ct_info->timeout[0]) {
1843                 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout))
1844                         return -EMSGSIZE;
1845         }
1846
1847 #if IS_ENABLED(CONFIG_NF_NAT)
1848         if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
1849                 return -EMSGSIZE;
1850 #endif
1851         nla_nest_end(skb, start);
1852
1853         return 0;
1854 }
1855
1856 void ovs_ct_free_action(const struct nlattr *a)
1857 {
1858         struct ovs_conntrack_info *ct_info = nla_data(a);
1859
1860         __ovs_ct_free_action(ct_info);
1861 }
1862
1863 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
1864 {
1865         if (ct_info->helper) {
1866 #if IS_ENABLED(CONFIG_NF_NAT)
1867                 if (ct_info->nat)
1868                         nf_nat_helper_put(ct_info->helper);
1869 #endif
1870                 nf_conntrack_helper_put(ct_info->helper);
1871         }
1872         if (ct_info->ct) {
1873                 if (ct_info->timeout[0])
1874                         nf_ct_destroy_timeout(ct_info->ct);
1875                 nf_ct_tmpl_free(ct_info->ct);
1876         }
1877 }
1878
1879 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1880 static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net)
1881 {
1882         int i, err;
1883
1884         ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info),
1885                                          GFP_KERNEL);
1886         if (!ovs_net->ct_limit_info)
1887                 return -ENOMEM;
1888
1889         ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT;
1890         ovs_net->ct_limit_info->limits =
1891                 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head),
1892                               GFP_KERNEL);
1893         if (!ovs_net->ct_limit_info->limits) {
1894                 kfree(ovs_net->ct_limit_info);
1895                 return -ENOMEM;
1896         }
1897
1898         for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++)
1899                 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]);
1900
1901         ovs_net->ct_limit_info->data =
1902                 nf_conncount_init(net, NFPROTO_INET, sizeof(u32));
1903
1904         if (IS_ERR(ovs_net->ct_limit_info->data)) {
1905                 err = PTR_ERR(ovs_net->ct_limit_info->data);
1906                 kfree(ovs_net->ct_limit_info->limits);
1907                 kfree(ovs_net->ct_limit_info);
1908                 pr_err("openvswitch: failed to init nf_conncount %d\n", err);
1909                 return err;
1910         }
1911         return 0;
1912 }
1913
1914 static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net)
1915 {
1916         const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info;
1917         int i;
1918
1919         nf_conncount_destroy(net, NFPROTO_INET, info->data);
1920         for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
1921                 struct hlist_head *head = &info->limits[i];
1922                 struct ovs_ct_limit *ct_limit;
1923                 struct hlist_node *next;
1924
1925                 hlist_for_each_entry_safe(ct_limit, next, head, hlist_node)
1926                         kfree_rcu(ct_limit, rcu);
1927         }
1928         kfree(info->limits);
1929         kfree(info);
1930 }
1931
1932 static struct sk_buff *
1933 ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd,
1934                              struct ovs_header **ovs_reply_header)
1935 {
1936         struct ovs_header *ovs_header = info->userhdr;
1937         struct sk_buff *skb;
1938
1939         skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1940         if (!skb)
1941                 return ERR_PTR(-ENOMEM);
1942
1943         *ovs_reply_header = genlmsg_put(skb, info->snd_portid,
1944                                         info->snd_seq,
1945                                         &dp_ct_limit_genl_family, 0, cmd);
1946
1947         if (!*ovs_reply_header) {
1948                 nlmsg_free(skb);
1949                 return ERR_PTR(-EMSGSIZE);
1950         }
1951         (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex;
1952
1953         return skb;
1954 }
1955
1956 static bool check_zone_id(int zone_id, u16 *pzone)
1957 {
1958         if (zone_id >= 0 && zone_id <= 65535) {
1959                 *pzone = (u16)zone_id;
1960                 return true;
1961         }
1962         return false;
1963 }
1964
1965 static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit,
1966                                        struct ovs_ct_limit_info *info)
1967 {
1968         struct ovs_zone_limit *zone_limit;
1969         int rem;
1970         u16 zone;
1971
1972         rem = NLA_ALIGN(nla_len(nla_zone_limit));
1973         zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1974
1975         while (rem >= sizeof(*zone_limit)) {
1976                 if (unlikely(zone_limit->zone_id ==
1977                                 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1978                         ovs_lock();
1979                         info->default_limit = zone_limit->limit;
1980                         ovs_unlock();
1981                 } else if (unlikely(!check_zone_id(
1982                                 zone_limit->zone_id, &zone))) {
1983                         OVS_NLERR(true, "zone id is out of range");
1984                 } else {
1985                         struct ovs_ct_limit *ct_limit;
1986
1987                         ct_limit = kmalloc(sizeof(*ct_limit),
1988                                            GFP_KERNEL_ACCOUNT);
1989                         if (!ct_limit)
1990                                 return -ENOMEM;
1991
1992                         ct_limit->zone = zone;
1993                         ct_limit->limit = zone_limit->limit;
1994
1995                         ovs_lock();
1996                         ct_limit_set(info, ct_limit);
1997                         ovs_unlock();
1998                 }
1999                 rem -= NLA_ALIGN(sizeof(*zone_limit));
2000                 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2001                                 NLA_ALIGN(sizeof(*zone_limit)));
2002         }
2003
2004         if (rem)
2005                 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem);
2006
2007         return 0;
2008 }
2009
2010 static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
2011                                        struct ovs_ct_limit_info *info)
2012 {
2013         struct ovs_zone_limit *zone_limit;
2014         int rem;
2015         u16 zone;
2016
2017         rem = NLA_ALIGN(nla_len(nla_zone_limit));
2018         zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2019
2020         while (rem >= sizeof(*zone_limit)) {
2021                 if (unlikely(zone_limit->zone_id ==
2022                                 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2023                         ovs_lock();
2024                         info->default_limit = OVS_CT_LIMIT_DEFAULT;
2025                         ovs_unlock();
2026                 } else if (unlikely(!check_zone_id(
2027                                 zone_limit->zone_id, &zone))) {
2028                         OVS_NLERR(true, "zone id is out of range");
2029                 } else {
2030                         ovs_lock();
2031                         ct_limit_del(info, zone);
2032                         ovs_unlock();
2033                 }
2034                 rem -= NLA_ALIGN(sizeof(*zone_limit));
2035                 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2036                                 NLA_ALIGN(sizeof(*zone_limit)));
2037         }
2038
2039         if (rem)
2040                 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem);
2041
2042         return 0;
2043 }
2044
2045 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
2046                                           struct sk_buff *reply)
2047 {
2048         struct ovs_zone_limit zone_limit = {
2049                 .zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE,
2050                 .limit   = info->default_limit,
2051         };
2052
2053         return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2054 }
2055
2056 static int __ovs_ct_limit_get_zone_limit(struct net *net,
2057                                          struct nf_conncount_data *data,
2058                                          u16 zone_id, u32 limit,
2059                                          struct sk_buff *reply)
2060 {
2061         struct nf_conntrack_zone ct_zone;
2062         struct ovs_zone_limit zone_limit;
2063         u32 conncount_key = zone_id;
2064
2065         zone_limit.zone_id = zone_id;
2066         zone_limit.limit = limit;
2067         nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0);
2068
2069         zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL,
2070                                               &ct_zone);
2071         return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2072 }
2073
2074 static int ovs_ct_limit_get_zone_limit(struct net *net,
2075                                        struct nlattr *nla_zone_limit,
2076                                        struct ovs_ct_limit_info *info,
2077                                        struct sk_buff *reply)
2078 {
2079         struct ovs_zone_limit *zone_limit;
2080         int rem, err;
2081         u32 limit;
2082         u16 zone;
2083
2084         rem = NLA_ALIGN(nla_len(nla_zone_limit));
2085         zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2086
2087         while (rem >= sizeof(*zone_limit)) {
2088                 if (unlikely(zone_limit->zone_id ==
2089                                 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2090                         err = ovs_ct_limit_get_default_limit(info, reply);
2091                         if (err)
2092                                 return err;
2093                 } else if (unlikely(!check_zone_id(zone_limit->zone_id,
2094                                                         &zone))) {
2095                         OVS_NLERR(true, "zone id is out of range");
2096                 } else {
2097                         rcu_read_lock();
2098                         limit = ct_limit_get(info, zone);
2099                         rcu_read_unlock();
2100
2101                         err = __ovs_ct_limit_get_zone_limit(
2102                                 net, info->data, zone, limit, reply);
2103                         if (err)
2104                                 return err;
2105                 }
2106                 rem -= NLA_ALIGN(sizeof(*zone_limit));
2107                 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2108                                 NLA_ALIGN(sizeof(*zone_limit)));
2109         }
2110
2111         if (rem)
2112                 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem);
2113
2114         return 0;
2115 }
2116
2117 static int ovs_ct_limit_get_all_zone_limit(struct net *net,
2118                                            struct ovs_ct_limit_info *info,
2119                                            struct sk_buff *reply)
2120 {
2121         struct ovs_ct_limit *ct_limit;
2122         struct hlist_head *head;
2123         int i, err = 0;
2124
2125         err = ovs_ct_limit_get_default_limit(info, reply);
2126         if (err)
2127                 return err;
2128
2129         rcu_read_lock();
2130         for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
2131                 head = &info->limits[i];
2132                 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
2133                         err = __ovs_ct_limit_get_zone_limit(net, info->data,
2134                                 ct_limit->zone, ct_limit->limit, reply);
2135                         if (err)
2136                                 goto exit_err;
2137                 }
2138         }
2139
2140 exit_err:
2141         rcu_read_unlock();
2142         return err;
2143 }
2144
2145 static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info)
2146 {
2147         struct nlattr **a = info->attrs;
2148         struct sk_buff *reply;
2149         struct ovs_header *ovs_reply_header;
2150         struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2151         struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2152         int err;
2153
2154         reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET,
2155                                              &ovs_reply_header);
2156         if (IS_ERR(reply))
2157                 return PTR_ERR(reply);
2158
2159         if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2160                 err = -EINVAL;
2161                 goto exit_err;
2162         }
2163
2164         err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2165                                           ct_limit_info);
2166         if (err)
2167                 goto exit_err;
2168
2169         static_branch_enable(&ovs_ct_limit_enabled);
2170
2171         genlmsg_end(reply, ovs_reply_header);
2172         return genlmsg_reply(reply, info);
2173
2174 exit_err:
2175         nlmsg_free(reply);
2176         return err;
2177 }
2178
2179 static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info)
2180 {
2181         struct nlattr **a = info->attrs;
2182         struct sk_buff *reply;
2183         struct ovs_header *ovs_reply_header;
2184         struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2185         struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2186         int err;
2187
2188         reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL,
2189                                              &ovs_reply_header);
2190         if (IS_ERR(reply))
2191                 return PTR_ERR(reply);
2192
2193         if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2194                 err = -EINVAL;
2195                 goto exit_err;
2196         }
2197
2198         err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2199                                           ct_limit_info);
2200         if (err)
2201                 goto exit_err;
2202
2203         genlmsg_end(reply, ovs_reply_header);
2204         return genlmsg_reply(reply, info);
2205
2206 exit_err:
2207         nlmsg_free(reply);
2208         return err;
2209 }
2210
2211 static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info)
2212 {
2213         struct nlattr **a = info->attrs;
2214         struct nlattr *nla_reply;
2215         struct sk_buff *reply;
2216         struct ovs_header *ovs_reply_header;
2217         struct net *net = sock_net(skb->sk);
2218         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2219         struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2220         int err;
2221
2222         reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET,
2223                                              &ovs_reply_header);
2224         if (IS_ERR(reply))
2225                 return PTR_ERR(reply);
2226
2227         nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT);
2228         if (!nla_reply) {
2229                 err = -EMSGSIZE;
2230                 goto exit_err;
2231         }
2232
2233         if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2234                 err = ovs_ct_limit_get_zone_limit(
2235                         net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info,
2236                         reply);
2237                 if (err)
2238                         goto exit_err;
2239         } else {
2240                 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info,
2241                                                       reply);
2242                 if (err)
2243                         goto exit_err;
2244         }
2245
2246         nla_nest_end(reply, nla_reply);
2247         genlmsg_end(reply, ovs_reply_header);
2248         return genlmsg_reply(reply, info);
2249
2250 exit_err:
2251         nlmsg_free(reply);
2252         return err;
2253 }
2254
2255 static const struct genl_small_ops ct_limit_genl_ops[] = {
2256         { .cmd = OVS_CT_LIMIT_CMD_SET,
2257                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2258                 .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2259                                                * privilege.
2260                                                */
2261                 .doit = ovs_ct_limit_cmd_set,
2262         },
2263         { .cmd = OVS_CT_LIMIT_CMD_DEL,
2264                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2265                 .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2266                                                * privilege.
2267                                                */
2268                 .doit = ovs_ct_limit_cmd_del,
2269         },
2270         { .cmd = OVS_CT_LIMIT_CMD_GET,
2271                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2272                 .flags = 0,               /* OK for unprivileged users. */
2273                 .doit = ovs_ct_limit_cmd_get,
2274         },
2275 };
2276
2277 static const struct genl_multicast_group ovs_ct_limit_multicast_group = {
2278         .name = OVS_CT_LIMIT_MCGROUP,
2279 };
2280
2281 struct genl_family dp_ct_limit_genl_family __ro_after_init = {
2282         .hdrsize = sizeof(struct ovs_header),
2283         .name = OVS_CT_LIMIT_FAMILY,
2284         .version = OVS_CT_LIMIT_VERSION,
2285         .maxattr = OVS_CT_LIMIT_ATTR_MAX,
2286         .policy = ct_limit_policy,
2287         .netnsok = true,
2288         .parallel_ops = true,
2289         .small_ops = ct_limit_genl_ops,
2290         .n_small_ops = ARRAY_SIZE(ct_limit_genl_ops),
2291         .resv_start_op = OVS_CT_LIMIT_CMD_GET + 1,
2292         .mcgrps = &ovs_ct_limit_multicast_group,
2293         .n_mcgrps = 1,
2294         .module = THIS_MODULE,
2295 };
2296 #endif
2297
2298 int ovs_ct_init(struct net *net)
2299 {
2300         unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
2301         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2302
2303         if (nf_connlabels_get(net, n_bits - 1)) {
2304                 ovs_net->xt_label = false;
2305                 OVS_NLERR(true, "Failed to set connlabel length");
2306         } else {
2307                 ovs_net->xt_label = true;
2308         }
2309
2310 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2311         return ovs_ct_limit_init(net, ovs_net);
2312 #else
2313         return 0;
2314 #endif
2315 }
2316
2317 void ovs_ct_exit(struct net *net)
2318 {
2319         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2320
2321 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2322         ovs_ct_limit_exit(net, ovs_net);
2323 #endif
2324
2325         if (ovs_net->xt_label)
2326                 nf_connlabels_put(net);
2327 }