net/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 ? 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 | (ct->mark & ~(mask));
 344         if (ct->mark != new_mark) {
 345                 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 /* Modelled after nf_nat_ipv[46]_fn().
 738  * range is only used for new, uninitialized NAT state.
 739  * Returns either NF_ACCEPT or NF_DROP.
 740  */
 741 static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 742                               enum ip_conntrack_info ctinfo,
 743                               const struct nf_nat_range2 *range,
 744                               enum nf_nat_manip_type maniptype)
 745 {
 746         int hooknum, nh_off, err = NF_ACCEPT;
 747
 748         nh_off = skb_network_offset(skb);
 749         skb_pull_rcsum(skb, nh_off);
 750
 751         /* See HOOK2MANIP(). */
 752         if (maniptype == NF_NAT_MANIP_SRC)
 753                 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
 754         else
 755                 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
 756
 757         switch (ctinfo) {
 758         case IP_CT_RELATED:
 759         case IP_CT_RELATED_REPLY:
 760                 if (IS_ENABLED(CONFIG_NF_NAT) &&
 761                     skb->protocol == htons(ETH_P_IP) &&
 762                     ip_hdr(skb)->protocol == IPPROTO_ICMP) {
 763                         if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
 764                                                            hooknum))
 765                                 err = NF_DROP;
 766                         goto push;
 767                 } else if (IS_ENABLED(CONFIG_IPV6) &&
 768                            skb->protocol == htons(ETH_P_IPV6)) {
 769                         __be16 frag_off;
 770                         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 771                         int hdrlen = ipv6_skip_exthdr(skb,
 772                                                       sizeof(struct ipv6hdr),
 773                                                       &nexthdr, &frag_off);
 774
 775                         if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
 776                                 if (!nf_nat_icmpv6_reply_translation(skb, ct,
 777                                                                      ctinfo,
 778                                                                      hooknum,
 779                                                                      hdrlen))
 780                                         err = NF_DROP;
 781                                 goto push;
 782                         }
 783                 }
 784                 /* Non-ICMP, fall thru to initialize if needed. */
 785                 fallthrough;
 786         case IP_CT_NEW:
 787                 /* Seen it before?  This can happen for loopback, retrans,
 788                  * or local packets.
 789                  */
 790                 if (!nf_nat_initialized(ct, maniptype)) {
 791                         /* Initialize according to the NAT action. */
 792                         err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
 793                                 /* Action is set up to establish a new
 794                                  * mapping.
 795                                  */
 796                                 ? nf_nat_setup_info(ct, range, maniptype)
 797                                 : nf_nat_alloc_null_binding(ct, hooknum);
 798                         if (err != NF_ACCEPT)
 799                                 goto push;
 800                 }
 801                 break;
 802
 803         case IP_CT_ESTABLISHED:
 804         case IP_CT_ESTABLISHED_REPLY:
 805                 break;
 806
 807         default:
 808                 err = NF_DROP;
 809                 goto push;
 810         }
 811
 812         err = nf_nat_packet(ct, ctinfo, hooknum, skb);
 813 push:
 814         skb_push_rcsum(skb, nh_off);
 815
 816         return err;
 817 }
 818
 819 static void ovs_nat_update_key(struct sw_flow_key *key,
 820                                const struct sk_buff *skb,
 821                                enum nf_nat_manip_type maniptype)
 822 {
 823         if (maniptype == NF_NAT_MANIP_SRC) {
 824                 __be16 src;
 825
 826                 key->ct_state |= OVS_CS_F_SRC_NAT;
 827                 if (key->eth.type == htons(ETH_P_IP))
 828                         key->ipv4.addr.src = ip_hdr(skb)->saddr;
 829                 else if (key->eth.type == htons(ETH_P_IPV6))
 830                         memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
 831                                sizeof(key->ipv6.addr.src));
 832                 else
 833                         return;
 834
 835                 if (key->ip.proto == IPPROTO_UDP)
 836                         src = udp_hdr(skb)->source;
 837                 else if (key->ip.proto == IPPROTO_TCP)
 838                         src = tcp_hdr(skb)->source;
 839                 else if (key->ip.proto == IPPROTO_SCTP)
 840                         src = sctp_hdr(skb)->source;
 841                 else
 842                         return;
 843
 844                 key->tp.src = src;
 845         } else {
 846                 __be16 dst;
 847
 848                 key->ct_state |= OVS_CS_F_DST_NAT;
 849                 if (key->eth.type == htons(ETH_P_IP))
 850                         key->ipv4.addr.dst = ip_hdr(skb)->daddr;
 851                 else if (key->eth.type == htons(ETH_P_IPV6))
 852                         memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
 853                                sizeof(key->ipv6.addr.dst));
 854                 else
 855                         return;
 856
 857                 if (key->ip.proto == IPPROTO_UDP)
 858                         dst = udp_hdr(skb)->dest;
 859                 else if (key->ip.proto == IPPROTO_TCP)
 860                         dst = tcp_hdr(skb)->dest;
 861                 else if (key->ip.proto == IPPROTO_SCTP)
 862                         dst = sctp_hdr(skb)->dest;
 863                 else
 864                         return;
 865
 866                 key->tp.dst = dst;
 867         }
 868 }
 869
 870 /* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
 871 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
 872                       const struct ovs_conntrack_info *info,
 873                       struct sk_buff *skb, struct nf_conn *ct,
 874                       enum ip_conntrack_info ctinfo)
 875 {
 876         enum nf_nat_manip_type maniptype;
 877         int err;
 878
 879         /* Add NAT extension if not confirmed yet. */
 880         if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
 881                 return NF_ACCEPT;   /* Can't NAT. */
 882
 883         /* Determine NAT type.
 884          * Check if the NAT type can be deduced from the tracked connection.
 885          * Make sure new expected connections (IP_CT_RELATED) are NATted only
 886          * when committing.
 887          */
 888         if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
 889             ct->status & IPS_NAT_MASK &&
 890             (ctinfo != IP_CT_RELATED || info->commit)) {
 891                 /* NAT an established or related connection like before. */
 892                 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
 893                         /* This is the REPLY direction for a connection
 894                          * for which NAT was applied in the forward
 895                          * direction.  Do the reverse NAT.
 896                          */
 897                         maniptype = ct->status & IPS_SRC_NAT
 898                                 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
 899                 else
 900                         maniptype = ct->status & IPS_SRC_NAT
 901                                 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
 902         } else if (info->nat & OVS_CT_SRC_NAT) {
 903                 maniptype = NF_NAT_MANIP_SRC;
 904         } else if (info->nat & OVS_CT_DST_NAT) {
 905                 maniptype = NF_NAT_MANIP_DST;
 906         } else {
 907                 return NF_ACCEPT; /* Connection is not NATed. */
 908         }
 909         err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
 910
 911         if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) {
 912                 if (ct->status & IPS_SRC_NAT) {
 913                         if (maniptype == NF_NAT_MANIP_SRC)
 914                                 maniptype = NF_NAT_MANIP_DST;
 915                         else
 916                                 maniptype = NF_NAT_MANIP_SRC;
 917
 918                         err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range,
 919                                                  maniptype);
 920                 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) {
 921                         err = ovs_ct_nat_execute(skb, ct, ctinfo, NULL,
 922                                                  NF_NAT_MANIP_SRC);
 923                 }
 924         }
 925
 926         /* Mark NAT done if successful and update the flow key. */
 927         if (err == NF_ACCEPT)
 928                 ovs_nat_update_key(key, skb, maniptype);
 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 (info->commit && info->helper && !nfct_help(ct)) {
1019                         int err = __nf_ct_try_assign_helper(ct, info->ct,
1020                                                             GFP_ATOMIC);
1021                         if (err)
1022                                 return err;
1023                         add_helper = true;
1024
1025                         /* helper installed, add seqadj if NAT is required */
1026                         if (info->nat && !nfct_seqadj(ct)) {
1027                                 if (!nfct_seqadj_ext_add(ct))
1028                                         return -EINVAL;
1029                         }
1030                 }
1031
1032                 /* Call the helper only if:
1033                  * - nf_conntrack_in() was executed above ("!cached") or a
1034                  *   helper was just attached ("add_helper") for a confirmed
1035                  *   connection, or
1036                  * - When committing an unconfirmed connection.
1037                  */
1038                 if ((nf_ct_is_confirmed(ct) ? !cached || add_helper :
1039                                               info->commit) &&
1040                     ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
1041                         return -EINVAL;
1042                 }
1043
1044                 if (nf_ct_protonum(ct) == IPPROTO_TCP &&
1045                     nf_ct_is_confirmed(ct) && nf_conntrack_tcp_established(ct)) {
1046                         /* Be liberal for tcp packets so that out-of-window
1047                          * packets are not marked invalid.
1048                          */
1049                         nf_ct_set_tcp_be_liberal(ct);
1050                 }
1051
1052                 nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1053         }
1054
1055         return 0;
1056 }
1057
1058 /* Lookup connection and read fields into key. */
1059 static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
1060                          const struct ovs_conntrack_info *info,
1061                          struct sk_buff *skb)
1062 {
1063         struct nf_conntrack_expect *exp;
1064
1065         /* If we pass an expected packet through nf_conntrack_in() the
1066          * expectation is typically removed, but the packet could still be
1067          * lost in upcall processing.  To prevent this from happening we
1068          * perform an explicit expectation lookup.  Expected connections are
1069          * always new, and will be passed through conntrack only when they are
1070          * committed, as it is OK to remove the expectation at that time.
1071          */
1072         exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
1073         if (exp) {
1074                 u8 state;
1075
1076                 /* NOTE: New connections are NATted and Helped only when
1077                  * committed, so we are not calling into NAT here.
1078                  */
1079                 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
1080                 __ovs_ct_update_key(key, state, &info->zone, exp->master);
1081         } else {
1082                 struct nf_conn *ct;
1083                 int err;
1084
1085                 err = __ovs_ct_lookup(net, key, info, skb);
1086                 if (err)
1087                         return err;
1088
1089                 ct = (struct nf_conn *)skb_nfct(skb);
1090                 if (ct)
1091                         nf_ct_deliver_cached_events(ct);
1092         }
1093
1094         return 0;
1095 }
1096
1097 static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
1098 {
1099         size_t i;
1100
1101         for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
1102                 if (labels->ct_labels_32[i])
1103                         return true;
1104
1105         return false;
1106 }
1107
1108 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1109 static struct hlist_head *ct_limit_hash_bucket(
1110         const struct ovs_ct_limit_info *info, u16 zone)
1111 {
1112         return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)];
1113 }
1114
1115 /* Call with ovs_mutex */
1116 static void ct_limit_set(const struct ovs_ct_limit_info *info,
1117                          struct ovs_ct_limit *new_ct_limit)
1118 {
1119         struct ovs_ct_limit *ct_limit;
1120         struct hlist_head *head;
1121
1122         head = ct_limit_hash_bucket(info, new_ct_limit->zone);
1123         hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1124                 if (ct_limit->zone == new_ct_limit->zone) {
1125                         hlist_replace_rcu(&ct_limit->hlist_node,
1126                                           &new_ct_limit->hlist_node);
1127                         kfree_rcu(ct_limit, rcu);
1128                         return;
1129                 }
1130         }
1131
1132         hlist_add_head_rcu(&new_ct_limit->hlist_node, head);
1133 }
1134
1135 /* Call with ovs_mutex */
1136 static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone)
1137 {
1138         struct ovs_ct_limit *ct_limit;
1139         struct hlist_head *head;
1140         struct hlist_node *n;
1141
1142         head = ct_limit_hash_bucket(info, zone);
1143         hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) {
1144                 if (ct_limit->zone == zone) {
1145                         hlist_del_rcu(&ct_limit->hlist_node);
1146                         kfree_rcu(ct_limit, rcu);
1147                         return;
1148                 }
1149         }
1150 }
1151
1152 /* Call with RCU read lock */
1153 static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone)
1154 {
1155         struct ovs_ct_limit *ct_limit;
1156         struct hlist_head *head;
1157
1158         head = ct_limit_hash_bucket(info, zone);
1159         hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1160                 if (ct_limit->zone == zone)
1161                         return ct_limit->limit;
1162         }
1163
1164         return info->default_limit;
1165 }
1166
1167 static int ovs_ct_check_limit(struct net *net,
1168                               const struct ovs_conntrack_info *info,
1169                               const struct nf_conntrack_tuple *tuple)
1170 {
1171         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1172         const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
1173         u32 per_zone_limit, connections;
1174         u32 conncount_key;
1175
1176         conncount_key = info->zone.id;
1177
1178         per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id);
1179         if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED)
1180                 return 0;
1181
1182         connections = nf_conncount_count(net, ct_limit_info->data,
1183                                          &conncount_key, tuple, &info->zone);
1184         if (connections > per_zone_limit)
1185                 return -ENOMEM;
1186
1187         return 0;
1188 }
1189 #endif
1190
1191 /* Lookup connection and confirm if unconfirmed. */
1192 static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
1193                          const struct ovs_conntrack_info *info,
1194                          struct sk_buff *skb)
1195 {
1196         enum ip_conntrack_info ctinfo;
1197         struct nf_conn *ct;
1198         int err;
1199
1200         err = __ovs_ct_lookup(net, key, info, skb);
1201         if (err)
1202                 return err;
1203
1204         /* The connection could be invalid, in which case this is a no-op.*/
1205         ct = nf_ct_get(skb, &ctinfo);
1206         if (!ct)
1207                 return 0;
1208
1209 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1210         if (static_branch_unlikely(&ovs_ct_limit_enabled)) {
1211                 if (!nf_ct_is_confirmed(ct)) {
1212                         err = ovs_ct_check_limit(net, info,
1213                                 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
1214                         if (err) {
1215                                 net_warn_ratelimited("openvswitch: zone: %u "
1216                                         "exceeds conntrack limit\n",
1217                                         info->zone.id);
1218                                 return err;
1219                         }
1220                 }
1221         }
1222 #endif
1223
1224         /* Set the conntrack event mask if given.  NEW and DELETE events have
1225          * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
1226          * typically would receive many kinds of updates.  Setting the event
1227          * mask allows those events to be filtered.  The set event mask will
1228          * remain in effect for the lifetime of the connection unless changed
1229          * by a further CT action with both the commit flag and the eventmask
1230          * option. */
1231         if (info->have_eventmask) {
1232                 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct);
1233
1234                 if (cache)
1235                         cache->ctmask = info->eventmask;
1236         }
1237
1238         /* Apply changes before confirming the connection so that the initial
1239          * conntrack NEW netlink event carries the values given in the CT
1240          * action.
1241          */
1242         if (info->mark.mask) {
1243                 err = ovs_ct_set_mark(ct, key, info->mark.value,
1244                                       info->mark.mask);
1245                 if (err)
1246                         return err;
1247         }
1248         if (!nf_ct_is_confirmed(ct)) {
1249                 err = ovs_ct_init_labels(ct, key, &info->labels.value,
1250                                          &info->labels.mask);
1251                 if (err)
1252                         return err;
1253
1254                 nf_conn_act_ct_ext_add(ct);
1255         } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1256                    labels_nonzero(&info->labels.mask)) {
1257                 err = ovs_ct_set_labels(ct, key, &info->labels.value,
1258                                         &info->labels.mask);
1259                 if (err)
1260                         return err;
1261         }
1262         /* This will take care of sending queued events even if the connection
1263          * is already confirmed.
1264          */
1265         if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1266                 return -EINVAL;
1267
1268         return 0;
1269 }
1270
1271 /* Trim the skb to the length specified by the IP/IPv6 header,
1272  * removing any trailing lower-layer padding. This prepares the skb
1273  * for higher-layer processing that assumes skb->len excludes padding
1274  * (such as nf_ip_checksum). The caller needs to pull the skb to the
1275  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
1276  */
1277 static int ovs_skb_network_trim(struct sk_buff *skb)
1278 {
1279         unsigned int len;
1280         int err;
1281
1282         switch (skb->protocol) {
1283         case htons(ETH_P_IP):
1284                 len = ntohs(ip_hdr(skb)->tot_len);
1285                 break;
1286         case htons(ETH_P_IPV6):
1287                 len = sizeof(struct ipv6hdr)
1288                         + ntohs(ipv6_hdr(skb)->payload_len);
1289                 break;
1290         default:
1291                 len = skb->len;
1292         }
1293
1294         err = pskb_trim_rcsum(skb, len);
1295         if (err)
1296                 kfree_skb(skb);
1297
1298         return err;
1299 }
1300
1301 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
1302  * value if 'skb' is freed.
1303  */
1304 int ovs_ct_execute(struct net *net, struct sk_buff *skb,
1305                    struct sw_flow_key *key,
1306                    const struct ovs_conntrack_info *info)
1307 {
1308         int nh_ofs;
1309         int err;
1310
1311         /* The conntrack module expects to be working at L3. */
1312         nh_ofs = skb_network_offset(skb);
1313         skb_pull_rcsum(skb, nh_ofs);
1314
1315         err = ovs_skb_network_trim(skb);
1316         if (err)
1317                 return err;
1318
1319         if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
1320                 err = handle_fragments(net, key, info->zone.id, skb);
1321                 if (err)
1322                         return err;
1323         }
1324
1325         if (info->commit)
1326                 err = ovs_ct_commit(net, key, info, skb);
1327         else
1328                 err = ovs_ct_lookup(net, key, info, skb);
1329
1330         skb_push_rcsum(skb, nh_ofs);
1331         if (err)
1332                 kfree_skb(skb);
1333         return err;
1334 }
1335
1336 int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key)
1337 {
1338         enum ip_conntrack_info ctinfo;
1339         struct nf_conn *ct;
1340
1341         ct = nf_ct_get(skb, &ctinfo);
1342
1343         nf_ct_put(ct);
1344         nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1345         ovs_ct_fill_key(skb, key, false);
1346
1347         return 0;
1348 }
1349
1350 static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
1351                              const struct sw_flow_key *key, bool log)
1352 {
1353         struct nf_conntrack_helper *helper;
1354         struct nf_conn_help *help;
1355         int ret = 0;
1356
1357         helper = nf_conntrack_helper_try_module_get(name, info->family,
1358                                                     key->ip.proto);
1359         if (!helper) {
1360                 OVS_NLERR(log, "Unknown helper \"%s\"", name);
1361                 return -EINVAL;
1362         }
1363
1364         help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL);
1365         if (!help) {
1366                 nf_conntrack_helper_put(helper);
1367                 return -ENOMEM;
1368         }
1369
1370 #if IS_ENABLED(CONFIG_NF_NAT)
1371         if (info->nat) {
1372                 ret = nf_nat_helper_try_module_get(name, info->family,
1373                                                    key->ip.proto);
1374                 if (ret) {
1375                         nf_conntrack_helper_put(helper);
1376                         OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d",
1377                                   name, ret);
1378                         return ret;
1379                 }
1380         }
1381 #endif
1382         rcu_assign_pointer(help->helper, helper);
1383         info->helper = helper;
1384         return ret;
1385 }
1386
1387 #if IS_ENABLED(CONFIG_NF_NAT)
1388 static int parse_nat(const struct nlattr *attr,
1389                      struct ovs_conntrack_info *info, bool log)
1390 {
1391         struct nlattr *a;
1392         int rem;
1393         bool have_ip_max = false;
1394         bool have_proto_max = false;
1395         bool ip_vers = (info->family == NFPROTO_IPV6);
1396
1397         nla_for_each_nested(a, attr, rem) {
1398                 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
1399                         [OVS_NAT_ATTR_SRC] = {0, 0},
1400                         [OVS_NAT_ATTR_DST] = {0, 0},
1401                         [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
1402                                                  sizeof(struct in6_addr)},
1403                         [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
1404                                                  sizeof(struct in6_addr)},
1405                         [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
1406                         [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
1407                         [OVS_NAT_ATTR_PERSISTENT] = {0, 0},
1408                         [OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
1409                         [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
1410                 };
1411                 int type = nla_type(a);
1412
1413                 if (type > OVS_NAT_ATTR_MAX) {
1414                         OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)",
1415                                   type, OVS_NAT_ATTR_MAX);
1416                         return -EINVAL;
1417                 }
1418
1419                 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
1420                         OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)",
1421                                   type, nla_len(a),
1422                                   ovs_nat_attr_lens[type][ip_vers]);
1423                         return -EINVAL;
1424                 }
1425
1426                 switch (type) {
1427                 case OVS_NAT_ATTR_SRC:
1428                 case OVS_NAT_ATTR_DST:
1429                         if (info->nat) {
1430                                 OVS_NLERR(log, "Only one type of NAT may be specified");
1431                                 return -ERANGE;
1432                         }
1433                         info->nat |= OVS_CT_NAT;
1434                         info->nat |= ((type == OVS_NAT_ATTR_SRC)
1435                                         ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
1436                         break;
1437
1438                 case OVS_NAT_ATTR_IP_MIN:
1439                         nla_memcpy(&info->range.min_addr, a,
1440                                    sizeof(info->range.min_addr));
1441                         info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1442                         break;
1443
1444                 case OVS_NAT_ATTR_IP_MAX:
1445                         have_ip_max = true;
1446                         nla_memcpy(&info->range.max_addr, a,
1447                                    sizeof(info->range.max_addr));
1448                         info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1449                         break;
1450
1451                 case OVS_NAT_ATTR_PROTO_MIN:
1452                         info->range.min_proto.all = htons(nla_get_u16(a));
1453                         info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1454                         break;
1455
1456                 case OVS_NAT_ATTR_PROTO_MAX:
1457                         have_proto_max = true;
1458                         info->range.max_proto.all = htons(nla_get_u16(a));
1459                         info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1460                         break;
1461
1462                 case OVS_NAT_ATTR_PERSISTENT:
1463                         info->range.flags |= NF_NAT_RANGE_PERSISTENT;
1464                         break;
1465
1466                 case OVS_NAT_ATTR_PROTO_HASH:
1467                         info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
1468                         break;
1469
1470                 case OVS_NAT_ATTR_PROTO_RANDOM:
1471                         info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
1472                         break;
1473
1474                 default:
1475                         OVS_NLERR(log, "Unknown nat attribute (%d)", type);
1476                         return -EINVAL;
1477                 }
1478         }
1479
1480         if (rem > 0) {
1481                 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem);
1482                 return -EINVAL;
1483         }
1484         if (!info->nat) {
1485                 /* Do not allow flags if no type is given. */
1486                 if (info->range.flags) {
1487                         OVS_NLERR(log,
1488                                   "NAT flags may be given only when NAT range (SRC or DST) is also specified."
1489                                   );
1490                         return -EINVAL;
1491                 }
1492                 info->nat = OVS_CT_NAT;   /* NAT existing connections. */
1493         } else if (!info->commit) {
1494                 OVS_NLERR(log,
1495                           "NAT attributes may be specified only when CT COMMIT flag is also specified."
1496                           );
1497                 return -EINVAL;
1498         }
1499         /* Allow missing IP_MAX. */
1500         if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
1501                 memcpy(&info->range.max_addr, &info->range.min_addr,
1502                        sizeof(info->range.max_addr));
1503         }
1504         /* Allow missing PROTO_MAX. */
1505         if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1506             !have_proto_max) {
1507                 info->range.max_proto.all = info->range.min_proto.all;
1508         }
1509         return 0;
1510 }
1511 #endif
1512
1513 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
1514         [OVS_CT_ATTR_COMMIT]    = { .minlen = 0, .maxlen = 0 },
1515         [OVS_CT_ATTR_FORCE_COMMIT]      = { .minlen = 0, .maxlen = 0 },
1516         [OVS_CT_ATTR_ZONE]      = { .minlen = sizeof(u16),
1517                                     .maxlen = sizeof(u16) },
1518         [OVS_CT_ATTR_MARK]      = { .minlen = sizeof(struct md_mark),
1519                                     .maxlen = sizeof(struct md_mark) },
1520         [OVS_CT_ATTR_LABELS]    = { .minlen = sizeof(struct md_labels),
1521                                     .maxlen = sizeof(struct md_labels) },
1522         [OVS_CT_ATTR_HELPER]    = { .minlen = 1,
1523                                     .maxlen = NF_CT_HELPER_NAME_LEN },
1524 #if IS_ENABLED(CONFIG_NF_NAT)
1525         /* NAT length is checked when parsing the nested attributes. */
1526         [OVS_CT_ATTR_NAT]       = { .minlen = 0, .maxlen = INT_MAX },
1527 #endif
1528         [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32),
1529                                     .maxlen = sizeof(u32) },
1530         [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1,
1531                                   .maxlen = CTNL_TIMEOUT_NAME_MAX },
1532 };
1533
1534 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
1535                     const char **helper, bool log)
1536 {
1537         struct nlattr *a;
1538         int rem;
1539
1540         nla_for_each_nested(a, attr, rem) {
1541                 int type = nla_type(a);
1542                 int maxlen;
1543                 int minlen;
1544
1545                 if (type > OVS_CT_ATTR_MAX) {
1546                         OVS_NLERR(log,
1547                                   "Unknown conntrack attr (type=%d, max=%d)",
1548                                   type, OVS_CT_ATTR_MAX);
1549                         return -EINVAL;
1550                 }
1551
1552                 maxlen = ovs_ct_attr_lens[type].maxlen;
1553                 minlen = ovs_ct_attr_lens[type].minlen;
1554                 if (nla_len(a) < minlen || nla_len(a) > maxlen) {
1555                         OVS_NLERR(log,
1556                                   "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
1557                                   type, nla_len(a), maxlen);
1558                         return -EINVAL;
1559                 }
1560
1561                 switch (type) {
1562                 case OVS_CT_ATTR_FORCE_COMMIT:
1563                         info->force = true;
1564                         fallthrough;
1565                 case OVS_CT_ATTR_COMMIT:
1566                         info->commit = true;
1567                         break;
1568 #ifdef CONFIG_NF_CONNTRACK_ZONES
1569                 case OVS_CT_ATTR_ZONE:
1570                         info->zone.id = nla_get_u16(a);
1571                         break;
1572 #endif
1573 #ifdef CONFIG_NF_CONNTRACK_MARK
1574                 case OVS_CT_ATTR_MARK: {
1575                         struct md_mark *mark = nla_data(a);
1576
1577                         if (!mark->mask) {
1578                                 OVS_NLERR(log, "ct_mark mask cannot be 0");
1579                                 return -EINVAL;
1580                         }
1581                         info->mark = *mark;
1582                         break;
1583                 }
1584 #endif
1585 #ifdef CONFIG_NF_CONNTRACK_LABELS
1586                 case OVS_CT_ATTR_LABELS: {
1587                         struct md_labels *labels = nla_data(a);
1588
1589                         if (!labels_nonzero(&labels->mask)) {
1590                                 OVS_NLERR(log, "ct_labels mask cannot be 0");
1591                                 return -EINVAL;
1592                         }
1593                         info->labels = *labels;
1594                         break;
1595                 }
1596 #endif
1597                 case OVS_CT_ATTR_HELPER:
1598                         *helper = nla_data(a);
1599                         if (!memchr(*helper, '\0', nla_len(a))) {
1600                                 OVS_NLERR(log, "Invalid conntrack helper");
1601                                 return -EINVAL;
1602                         }
1603                         break;
1604 #if IS_ENABLED(CONFIG_NF_NAT)
1605                 case OVS_CT_ATTR_NAT: {
1606                         int err = parse_nat(a, info, log);
1607
1608                         if (err)
1609                                 return err;
1610                         break;
1611                 }
1612 #endif
1613                 case OVS_CT_ATTR_EVENTMASK:
1614                         info->have_eventmask = true;
1615                         info->eventmask = nla_get_u32(a);
1616                         break;
1617 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1618                 case OVS_CT_ATTR_TIMEOUT:
1619                         memcpy(info->timeout, nla_data(a), nla_len(a));
1620                         if (!memchr(info->timeout, '\0', nla_len(a))) {
1621                                 OVS_NLERR(log, "Invalid conntrack timeout");
1622                                 return -EINVAL;
1623                         }
1624                         break;
1625 #endif
1626
1627                 default:
1628                         OVS_NLERR(log, "Unknown conntrack attr (%d)",
1629                                   type);
1630                         return -EINVAL;
1631                 }
1632         }
1633
1634 #ifdef CONFIG_NF_CONNTRACK_MARK
1635         if (!info->commit && info->mark.mask) {
1636                 OVS_NLERR(log,
1637                           "Setting conntrack mark requires 'commit' flag.");
1638                 return -EINVAL;
1639         }
1640 #endif
1641 #ifdef CONFIG_NF_CONNTRACK_LABELS
1642         if (!info->commit && labels_nonzero(&info->labels.mask)) {
1643                 OVS_NLERR(log,
1644                           "Setting conntrack labels requires 'commit' flag.");
1645                 return -EINVAL;
1646         }
1647 #endif
1648         if (rem > 0) {
1649                 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
1650                 return -EINVAL;
1651         }
1652
1653         return 0;
1654 }
1655
1656 bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
1657 {
1658         if (attr == OVS_KEY_ATTR_CT_STATE)
1659                 return true;
1660         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1661             attr == OVS_KEY_ATTR_CT_ZONE)
1662                 return true;
1663         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1664             attr == OVS_KEY_ATTR_CT_MARK)
1665                 return true;
1666         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1667             attr == OVS_KEY_ATTR_CT_LABELS) {
1668                 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1669
1670                 return ovs_net->xt_label;
1671         }
1672
1673         return false;
1674 }
1675
1676 int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
1677                        const struct sw_flow_key *key,
1678                        struct sw_flow_actions **sfa,  bool log)
1679 {
1680         struct ovs_conntrack_info ct_info;
1681         const char *helper = NULL;
1682         u16 family;
1683         int err;
1684
1685         family = key_to_nfproto(key);
1686         if (family == NFPROTO_UNSPEC) {
1687                 OVS_NLERR(log, "ct family unspecified");
1688                 return -EINVAL;
1689         }
1690
1691         memset(&ct_info, 0, sizeof(ct_info));
1692         ct_info.family = family;
1693
1694         nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
1695                         NF_CT_DEFAULT_ZONE_DIR, 0);
1696
1697         err = parse_ct(attr, &ct_info, &helper, log);
1698         if (err)
1699                 return err;
1700
1701         /* Set up template for tracking connections in specific zones. */
1702         ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
1703         if (!ct_info.ct) {
1704                 OVS_NLERR(log, "Failed to allocate conntrack template");
1705                 return -ENOMEM;
1706         }
1707
1708         if (ct_info.timeout[0]) {
1709                 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto,
1710                                       ct_info.timeout))
1711                         pr_info_ratelimited("Failed to associated timeout "
1712                                             "policy `%s'\n", ct_info.timeout);
1713                 else
1714                         ct_info.nf_ct_timeout = rcu_dereference(
1715                                 nf_ct_timeout_find(ct_info.ct)->timeout);
1716
1717         }
1718
1719         if (helper) {
1720                 err = ovs_ct_add_helper(&ct_info, helper, key, log);
1721                 if (err)
1722                         goto err_free_ct;
1723         }
1724
1725         err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
1726                                  sizeof(ct_info), log);
1727         if (err)
1728                 goto err_free_ct;
1729
1730         __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
1731         return 0;
1732 err_free_ct:
1733         __ovs_ct_free_action(&ct_info);
1734         return err;
1735 }
1736
1737 #if IS_ENABLED(CONFIG_NF_NAT)
1738 static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
1739                                struct sk_buff *skb)
1740 {
1741         struct nlattr *start;
1742
1743         start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT);
1744         if (!start)
1745                 return false;
1746
1747         if (info->nat & OVS_CT_SRC_NAT) {
1748                 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
1749                         return false;
1750         } else if (info->nat & OVS_CT_DST_NAT) {
1751                 if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
1752                         return false;
1753         } else {
1754                 goto out;
1755         }
1756
1757         if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
1758                 if (IS_ENABLED(CONFIG_NF_NAT) &&
1759                     info->family == NFPROTO_IPV4) {
1760                         if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
1761                                             info->range.min_addr.ip) ||
1762                             (info->range.max_addr.ip
1763                              != info->range.min_addr.ip &&
1764                              (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
1765                                               info->range.max_addr.ip))))
1766                                 return false;
1767                 } else if (IS_ENABLED(CONFIG_IPV6) &&
1768                            info->family == NFPROTO_IPV6) {
1769                         if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
1770                                              &info->range.min_addr.in6) ||
1771                             (memcmp(&info->range.max_addr.in6,
1772                                     &info->range.min_addr.in6,
1773                                     sizeof(info->range.max_addr.in6)) &&
1774                              (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
1775                                                &info->range.max_addr.in6))))
1776                                 return false;
1777                 } else {
1778                         return false;
1779                 }
1780         }
1781         if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1782             (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
1783                          ntohs(info->range.min_proto.all)) ||
1784              (info->range.max_proto.all != info->range.min_proto.all &&
1785               nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
1786                           ntohs(info->range.max_proto.all)))))
1787                 return false;
1788
1789         if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
1790             nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
1791                 return false;
1792         if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
1793             nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
1794                 return false;
1795         if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
1796             nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
1797                 return false;
1798 out:
1799         nla_nest_end(skb, start);
1800
1801         return true;
1802 }
1803 #endif
1804
1805 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
1806                           struct sk_buff *skb)
1807 {
1808         struct nlattr *start;
1809
1810         start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT);
1811         if (!start)
1812                 return -EMSGSIZE;
1813
1814         if (ct_info->commit && nla_put_flag(skb, ct_info->force
1815                                             ? OVS_CT_ATTR_FORCE_COMMIT
1816                                             : OVS_CT_ATTR_COMMIT))
1817                 return -EMSGSIZE;
1818         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1819             nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
1820                 return -EMSGSIZE;
1821         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
1822             nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
1823                     &ct_info->mark))
1824                 return -EMSGSIZE;
1825         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1826             labels_nonzero(&ct_info->labels.mask) &&
1827             nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
1828                     &ct_info->labels))
1829                 return -EMSGSIZE;
1830         if (ct_info->helper) {
1831                 if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
1832                                    ct_info->helper->name))
1833                         return -EMSGSIZE;
1834         }
1835         if (ct_info->have_eventmask &&
1836             nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask))
1837                 return -EMSGSIZE;
1838         if (ct_info->timeout[0]) {
1839                 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout))
1840                         return -EMSGSIZE;
1841         }
1842
1843 #if IS_ENABLED(CONFIG_NF_NAT)
1844         if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
1845                 return -EMSGSIZE;
1846 #endif
1847         nla_nest_end(skb, start);
1848
1849         return 0;
1850 }
1851
1852 void ovs_ct_free_action(const struct nlattr *a)
1853 {
1854         struct ovs_conntrack_info *ct_info = nla_data(a);
1855
1856         __ovs_ct_free_action(ct_info);
1857 }
1858
1859 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
1860 {
1861         if (ct_info->helper) {
1862 #if IS_ENABLED(CONFIG_NF_NAT)
1863                 if (ct_info->nat)
1864                         nf_nat_helper_put(ct_info->helper);
1865 #endif
1866                 nf_conntrack_helper_put(ct_info->helper);
1867         }
1868         if (ct_info->ct) {
1869                 if (ct_info->timeout[0])
1870                         nf_ct_destroy_timeout(ct_info->ct);
1871                 nf_ct_tmpl_free(ct_info->ct);
1872         }
1873 }
1874
1875 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1876 static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net)
1877 {
1878         int i, err;
1879
1880         ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info),
1881                                          GFP_KERNEL);
1882         if (!ovs_net->ct_limit_info)
1883                 return -ENOMEM;
1884
1885         ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT;
1886         ovs_net->ct_limit_info->limits =
1887                 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head),
1888                               GFP_KERNEL);
1889         if (!ovs_net->ct_limit_info->limits) {
1890                 kfree(ovs_net->ct_limit_info);
1891                 return -ENOMEM;
1892         }
1893
1894         for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++)
1895                 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]);
1896
1897         ovs_net->ct_limit_info->data =
1898                 nf_conncount_init(net, NFPROTO_INET, sizeof(u32));
1899
1900         if (IS_ERR(ovs_net->ct_limit_info->data)) {
1901                 err = PTR_ERR(ovs_net->ct_limit_info->data);
1902                 kfree(ovs_net->ct_limit_info->limits);
1903                 kfree(ovs_net->ct_limit_info);
1904                 pr_err("openvswitch: failed to init nf_conncount %d\n", err);
1905                 return err;
1906         }
1907         return 0;
1908 }
1909
1910 static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net)
1911 {
1912         const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info;
1913         int i;
1914
1915         nf_conncount_destroy(net, NFPROTO_INET, info->data);
1916         for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
1917                 struct hlist_head *head = &info->limits[i];
1918                 struct ovs_ct_limit *ct_limit;
1919
1920                 hlist_for_each_entry_rcu(ct_limit, head, hlist_node,
1921                                          lockdep_ovsl_is_held())
1922                         kfree_rcu(ct_limit, rcu);
1923         }
1924         kfree(info->limits);
1925         kfree(info);
1926 }
1927
1928 static struct sk_buff *
1929 ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd,
1930                              struct ovs_header **ovs_reply_header)
1931 {
1932         struct ovs_header *ovs_header = info->userhdr;
1933         struct sk_buff *skb;
1934
1935         skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1936         if (!skb)
1937                 return ERR_PTR(-ENOMEM);
1938
1939         *ovs_reply_header = genlmsg_put(skb, info->snd_portid,
1940                                         info->snd_seq,
1941                                         &dp_ct_limit_genl_family, 0, cmd);
1942
1943         if (!*ovs_reply_header) {
1944                 nlmsg_free(skb);
1945                 return ERR_PTR(-EMSGSIZE);
1946         }
1947         (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex;
1948
1949         return skb;
1950 }
1951
1952 static bool check_zone_id(int zone_id, u16 *pzone)
1953 {
1954         if (zone_id >= 0 && zone_id <= 65535) {
1955                 *pzone = (u16)zone_id;
1956                 return true;
1957         }
1958         return false;
1959 }
1960
1961 static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit,
1962                                        struct ovs_ct_limit_info *info)
1963 {
1964         struct ovs_zone_limit *zone_limit;
1965         int rem;
1966         u16 zone;
1967
1968         rem = NLA_ALIGN(nla_len(nla_zone_limit));
1969         zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1970
1971         while (rem >= sizeof(*zone_limit)) {
1972                 if (unlikely(zone_limit->zone_id ==
1973                                 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1974                         ovs_lock();
1975                         info->default_limit = zone_limit->limit;
1976                         ovs_unlock();
1977                 } else if (unlikely(!check_zone_id(
1978                                 zone_limit->zone_id, &zone))) {
1979                         OVS_NLERR(true, "zone id is out of range");
1980                 } else {
1981                         struct ovs_ct_limit *ct_limit;
1982
1983                         ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL);
1984                         if (!ct_limit)
1985                                 return -ENOMEM;
1986
1987                         ct_limit->zone = zone;
1988                         ct_limit->limit = zone_limit->limit;
1989
1990                         ovs_lock();
1991                         ct_limit_set(info, ct_limit);
1992                         ovs_unlock();
1993                 }
1994                 rem -= NLA_ALIGN(sizeof(*zone_limit));
1995                 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
1996                                 NLA_ALIGN(sizeof(*zone_limit)));
1997         }
1998
1999         if (rem)
2000                 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem);
2001
2002         return 0;
2003 }
2004
2005 static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
2006                                        struct ovs_ct_limit_info *info)
2007 {
2008         struct ovs_zone_limit *zone_limit;
2009         int rem;
2010         u16 zone;
2011
2012         rem = NLA_ALIGN(nla_len(nla_zone_limit));
2013         zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2014
2015         while (rem >= sizeof(*zone_limit)) {
2016                 if (unlikely(zone_limit->zone_id ==
2017                                 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2018                         ovs_lock();
2019                         info->default_limit = OVS_CT_LIMIT_DEFAULT;
2020                         ovs_unlock();
2021                 } else if (unlikely(!check_zone_id(
2022                                 zone_limit->zone_id, &zone))) {
2023                         OVS_NLERR(true, "zone id is out of range");
2024                 } else {
2025                         ovs_lock();
2026                         ct_limit_del(info, zone);
2027                         ovs_unlock();
2028                 }
2029                 rem -= NLA_ALIGN(sizeof(*zone_limit));
2030                 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2031                                 NLA_ALIGN(sizeof(*zone_limit)));
2032         }
2033
2034         if (rem)
2035                 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem);
2036
2037         return 0;
2038 }
2039
2040 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
2041                                           struct sk_buff *reply)
2042 {
2043         struct ovs_zone_limit zone_limit = {
2044                 .zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE,
2045                 .limit   = info->default_limit,
2046         };
2047
2048         return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2049 }
2050
2051 static int __ovs_ct_limit_get_zone_limit(struct net *net,
2052                                          struct nf_conncount_data *data,
2053                                          u16 zone_id, u32 limit,
2054                                          struct sk_buff *reply)
2055 {
2056         struct nf_conntrack_zone ct_zone;
2057         struct ovs_zone_limit zone_limit;
2058         u32 conncount_key = zone_id;
2059
2060         zone_limit.zone_id = zone_id;
2061         zone_limit.limit = limit;
2062         nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0);
2063
2064         zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL,
2065                                               &ct_zone);
2066         return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2067 }
2068
2069 static int ovs_ct_limit_get_zone_limit(struct net *net,
2070                                        struct nlattr *nla_zone_limit,
2071                                        struct ovs_ct_limit_info *info,
2072                                        struct sk_buff *reply)
2073 {
2074         struct ovs_zone_limit *zone_limit;
2075         int rem, err;
2076         u32 limit;
2077         u16 zone;
2078
2079         rem = NLA_ALIGN(nla_len(nla_zone_limit));
2080         zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2081
2082         while (rem >= sizeof(*zone_limit)) {
2083                 if (unlikely(zone_limit->zone_id ==
2084                                 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2085                         err = ovs_ct_limit_get_default_limit(info, reply);
2086                         if (err)
2087                                 return err;
2088                 } else if (unlikely(!check_zone_id(zone_limit->zone_id,
2089                                                         &zone))) {
2090                         OVS_NLERR(true, "zone id is out of range");
2091                 } else {
2092                         rcu_read_lock();
2093                         limit = ct_limit_get(info, zone);
2094                         rcu_read_unlock();
2095
2096                         err = __ovs_ct_limit_get_zone_limit(
2097                                 net, info->data, zone, limit, reply);
2098                         if (err)
2099                                 return err;
2100                 }
2101                 rem -= NLA_ALIGN(sizeof(*zone_limit));
2102                 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2103                                 NLA_ALIGN(sizeof(*zone_limit)));
2104         }
2105
2106         if (rem)
2107                 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem);
2108
2109         return 0;
2110 }
2111
2112 static int ovs_ct_limit_get_all_zone_limit(struct net *net,
2113                                            struct ovs_ct_limit_info *info,
2114                                            struct sk_buff *reply)
2115 {
2116         struct ovs_ct_limit *ct_limit;
2117         struct hlist_head *head;
2118         int i, err = 0;
2119
2120         err = ovs_ct_limit_get_default_limit(info, reply);
2121         if (err)
2122                 return err;
2123
2124         rcu_read_lock();
2125         for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
2126                 head = &info->limits[i];
2127                 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
2128                         err = __ovs_ct_limit_get_zone_limit(net, info->data,
2129                                 ct_limit->zone, ct_limit->limit, reply);
2130                         if (err)
2131                                 goto exit_err;
2132                 }
2133         }
2134
2135 exit_err:
2136         rcu_read_unlock();
2137         return err;
2138 }
2139
2140 static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info)
2141 {
2142         struct nlattr **a = info->attrs;
2143         struct sk_buff *reply;
2144         struct ovs_header *ovs_reply_header;
2145         struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2146         struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2147         int err;
2148
2149         reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET,
2150                                              &ovs_reply_header);
2151         if (IS_ERR(reply))
2152                 return PTR_ERR(reply);
2153
2154         if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2155                 err = -EINVAL;
2156                 goto exit_err;
2157         }
2158
2159         err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2160                                           ct_limit_info);
2161         if (err)
2162                 goto exit_err;
2163
2164         static_branch_enable(&ovs_ct_limit_enabled);
2165
2166         genlmsg_end(reply, ovs_reply_header);
2167         return genlmsg_reply(reply, info);
2168
2169 exit_err:
2170         nlmsg_free(reply);
2171         return err;
2172 }
2173
2174 static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info)
2175 {
2176         struct nlattr **a = info->attrs;
2177         struct sk_buff *reply;
2178         struct ovs_header *ovs_reply_header;
2179         struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2180         struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2181         int err;
2182
2183         reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL,
2184                                              &ovs_reply_header);
2185         if (IS_ERR(reply))
2186                 return PTR_ERR(reply);
2187
2188         if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2189                 err = -EINVAL;
2190                 goto exit_err;
2191         }
2192
2193         err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2194                                           ct_limit_info);
2195         if (err)
2196                 goto exit_err;
2197
2198         genlmsg_end(reply, ovs_reply_header);
2199         return genlmsg_reply(reply, info);
2200
2201 exit_err:
2202         nlmsg_free(reply);
2203         return err;
2204 }
2205
2206 static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info)
2207 {
2208         struct nlattr **a = info->attrs;
2209         struct nlattr *nla_reply;
2210         struct sk_buff *reply;
2211         struct ovs_header *ovs_reply_header;
2212         struct net *net = sock_net(skb->sk);
2213         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2214         struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2215         int err;
2216
2217         reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET,
2218                                              &ovs_reply_header);
2219         if (IS_ERR(reply))
2220                 return PTR_ERR(reply);
2221
2222         nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT);
2223         if (!nla_reply) {
2224                 err = -EMSGSIZE;
2225                 goto exit_err;
2226         }
2227
2228         if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2229                 err = ovs_ct_limit_get_zone_limit(
2230                         net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info,
2231                         reply);
2232                 if (err)
2233                         goto exit_err;
2234         } else {
2235                 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info,
2236                                                       reply);
2237                 if (err)
2238                         goto exit_err;
2239         }
2240
2241         nla_nest_end(reply, nla_reply);
2242         genlmsg_end(reply, ovs_reply_header);
2243         return genlmsg_reply(reply, info);
2244
2245 exit_err:
2246         nlmsg_free(reply);
2247         return err;
2248 }
2249
2250 static const struct genl_small_ops ct_limit_genl_ops[] = {
2251         { .cmd = OVS_CT_LIMIT_CMD_SET,
2252                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2253                 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2254                                            * privilege. */
2255                 .doit = ovs_ct_limit_cmd_set,
2256         },
2257         { .cmd = OVS_CT_LIMIT_CMD_DEL,
2258                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2259                 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2260                                            * privilege. */
2261                 .doit = ovs_ct_limit_cmd_del,
2262         },
2263         { .cmd = OVS_CT_LIMIT_CMD_GET,
2264                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2265                 .flags = 0,               /* OK for unprivileged users. */
2266                 .doit = ovs_ct_limit_cmd_get,
2267         },
2268 };
2269
2270 static const struct genl_multicast_group ovs_ct_limit_multicast_group = {
2271         .name = OVS_CT_LIMIT_MCGROUP,
2272 };
2273
2274 struct genl_family dp_ct_limit_genl_family __ro_after_init = {
2275         .hdrsize = sizeof(struct ovs_header),
2276         .name = OVS_CT_LIMIT_FAMILY,
2277         .version = OVS_CT_LIMIT_VERSION,
2278         .maxattr = OVS_CT_LIMIT_ATTR_MAX,
2279         .policy = ct_limit_policy,
2280         .netnsok = true,
2281         .parallel_ops = true,
2282         .small_ops = ct_limit_genl_ops,
2283         .n_small_ops = ARRAY_SIZE(ct_limit_genl_ops),
2284         .mcgrps = &ovs_ct_limit_multicast_group,
2285         .n_mcgrps = 1,
2286         .module = THIS_MODULE,
2287 };
2288 #endif
2289
2290 int ovs_ct_init(struct net *net)
2291 {
2292         unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
2293         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2294
2295         if (nf_connlabels_get(net, n_bits - 1)) {
2296                 ovs_net->xt_label = false;
2297                 OVS_NLERR(true, "Failed to set connlabel length");
2298         } else {
2299                 ovs_net->xt_label = true;
2300         }
2301
2302 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2303         return ovs_ct_limit_init(net, ovs_net);
2304 #else
2305         return 0;
2306 #endif
2307 }
2308
2309 void ovs_ct_exit(struct net *net)
2310 {
2311         struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2312
2313 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2314         ovs_ct_limit_exit(net, ovs_net);
2315 #endif
2316
2317         if (ovs_net->xt_label)
2318                 nf_connlabels_put(net);
2319 }