src/plugins/nat/out2in_ed.c

   1 /*
   2  * Copyright (c) 2018 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15 /**
  16  * @file
  17  * @brief NAT44 endpoint-dependent outside to inside network translation
  18  */
  19
  20 #include <vlib/vlib.h>
  21 #include <vnet/vnet.h>
  22 #include <vnet/pg/pg.h>
  23 #include <vnet/ip/ip.h>
  24 #include <vnet/ethernet/ethernet.h>
  25 #include <vnet/fib/ip4_fib.h>
  26 #include <vnet/udp/udp.h>
  27 #include <vppinfra/error.h>
  28 #include <nat/nat.h>
  29 #include <nat/nat_ipfix_logging.h>
  30 #include <nat/nat_inlines.h>
  31 #include <nat/nat44/inlines.h>
  32 #include <nat/nat_syslog.h>
  33 #include <nat/nat_ha.h>
  34 #include <nat/nat44/ed_inlines.h>
  35
  36 static char *nat_out2in_ed_error_strings[] = {
  37 #define _(sym,string) string,
  38   foreach_nat_out2in_ed_error
  39 #undef _
  40 };
  41
  42 typedef struct
  43 {
  44   u32 sw_if_index;
  45   u32 next_index;
  46   u32 session_index;
  47   u32 is_slow_path;
  48 } nat44_ed_out2in_trace_t;
  49
  50 static u8 *
  51 format_nat44_ed_out2in_trace (u8 * s, va_list * args)
  52 {
  53   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  54   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  55   nat44_ed_out2in_trace_t *t = va_arg (*args, nat44_ed_out2in_trace_t *);
  56   char *tag;
  57
  58   tag =
  59     t->is_slow_path ? "NAT44_OUT2IN_ED_SLOW_PATH" :
  60     "NAT44_OUT2IN_ED_FAST_PATH";
  61
  62   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  63               t->sw_if_index, t->next_index, t->session_index);
  64
  65   return s;
  66 }
  67
  68 static inline u32
  69 icmp_out2in_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
  70                           ip4_header_t * ip0, icmp46_header_t * icmp0,
  71                           u32 sw_if_index0, u32 rx_fib_index0,
  72                           vlib_node_runtime_t * node, u32 next0, f64 now,
  73                           u32 thread_index, snat_session_t ** p_s0)
  74 {
  75   vlib_main_t *vm = vlib_get_main ();
  76
  77   next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
  78                        next0, thread_index, p_s0, 0);
  79   snat_session_t *s0 = *p_s0;
  80   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
  81     {
  82       /* Accounting */
  83       nat44_session_update_counters (s0, now,
  84                                      vlib_buffer_length_in_chain
  85                                      (vm, b0), thread_index);
  86       /* Per-user LRU list maintenance */
  87       nat44_session_update_lru (sm, s0, thread_index);
  88     }
  89   return next0;
  90 }
  91
  92 #ifndef CLIB_MARCH_VARIANT
  93 int
  94 nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  95 {
  96   snat_main_t *sm = &snat_main;
  97   nat44_is_idle_session_ctx_t *ctx = arg;
  98   snat_session_t *s;
  99   u64 sess_timeout_time;
 100   u8 proto;
 101   u16 r_port, l_port;
 102   ip4_address_t *l_addr, *r_addr;
 103   u32 fib_index;
 104   clib_bihash_kv_16_8_t ed_kv;
 105   int i;
 106   //snat_address_t *a;
 107   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 108                                                        ctx->thread_index);
 109
 110   s = pool_elt_at_index (tsm->sessions, kv->value);
 111   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 112   if (ctx->now >= sess_timeout_time)
 113     {
 114       l_addr = &s->in2out.addr;
 115       r_addr = &s->ext_host_addr;
 116       fib_index = s->in2out.fib_index;
 117       if (snat_is_unk_proto_session (s))
 118         {
 119           proto = s->in2out.port;
 120           r_port = 0;
 121           l_port = 0;
 122         }
 123       else
 124         {
 125           proto = nat_proto_to_ip_proto (s->nat_proto);
 126           l_port = s->in2out.port;
 127           r_port = s->ext_host_port;
 128         }
 129       if (is_twice_nat_session (s))
 130         {
 131           r_addr = &s->ext_host_nat_addr;
 132           r_port = s->ext_host_nat_port;
 133         }
 134       init_ed_k (&ed_kv, *l_addr, l_port, *r_addr, r_port, fib_index, proto);
 135       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &ed_kv, 0))
 136         nat_elog_warn ("in2out_ed key del failed");
 137
 138       if (snat_is_unk_proto_session (s))
 139         goto delete;
 140
 141       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 142                                            s->in2out.addr.as_u32,
 143                                            s->out2in.addr.as_u32,
 144                                            s->nat_proto,
 145                                            s->in2out.port,
 146                                            s->out2in.port,
 147                                            s->in2out.fib_index);
 148
 149       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 150                              &s->in2out.addr, s->in2out.port,
 151                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 152                              &s->out2in.addr, s->out2in.port,
 153                              &s->ext_host_addr, s->ext_host_port,
 154                              s->nat_proto, is_twice_nat_session (s));
 155
 156       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 157                    s->ext_host_port, s->nat_proto, s->out2in.fib_index,
 158                    ctx->thread_index);
 159
 160       if (is_twice_nat_session (s))
 161         {
 162           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 163             {
 164               // FIXME TODO this is obviously wrong code ... needs fix!
 165               //       key.protocol = s->nat_proto;
 166               //       key.port = s->ext_host_nat_port;
 167               //       a = sm->twice_nat_addresses + i;
 168               //       if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 169               //      {
 170               //        snat_free_outside_address_and_port (sm->twice_nat_addresses,
 171               //                                            ctx->thread_index,
 172               //                                            &key);
 173               //        break;
 174               //      }
 175             }
 176         }
 177
 178       if (snat_is_session_static (s))
 179         goto delete;
 180
 181       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 182                                           &s->out2in.addr, s->out2in.port,
 183                                           s->nat_proto);
 184     delete:
 185       nat_ed_session_delete (sm, s, ctx->thread_index, 1);
 186       return 1;
 187     }
 188
 189   return 0;
 190 }
 191 #endif
 192
 193 static snat_session_t *
 194 create_session_for_static_mapping_ed (snat_main_t * sm,
 195                                       vlib_buffer_t * b,
 196                                       ip4_address_t i2o_addr,
 197                                       u16 i2o_port,
 198                                       u32 i2o_fib_index,
 199                                       ip4_address_t o2i_addr,
 200                                       u16 o2i_port,
 201                                       u32 o2i_fib_index,
 202                                       nat_protocol_t nat_proto,
 203                                       vlib_node_runtime_t * node,
 204                                       u32 rx_fib_index,
 205                                       u32 thread_index,
 206                                       twice_nat_type_t twice_nat,
 207                                       lb_nat_type_t lb_nat, f64 now)
 208 {
 209   snat_session_t *s;
 210   ip4_header_t *ip;
 211   udp_header_t *udp;
 212   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 213   clib_bihash_kv_16_8_t kv;
 214   nat44_is_idle_session_ctx_t ctx;
 215
 216   if (PREDICT_FALSE
 217       (nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index)))
 218     {
 219       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 220       nat_elog_notice ("maximum sessions exceeded");
 221       return 0;
 222     }
 223
 224   s = nat_ed_session_alloc (sm, thread_index, now, nat_proto);
 225   if (!s)
 226     {
 227       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 228       nat_elog_warn ("create NAT session failed");
 229       return 0;
 230     }
 231
 232   ip = vlib_buffer_get_current (b);
 233   udp = ip4_next_header (ip);
 234
 235   s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 236   s->ext_host_port = nat_proto == NAT_PROTOCOL_ICMP ? 0 : udp->src_port;
 237   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 238   if (lb_nat)
 239     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 240   if (lb_nat == AFFINITY_LB_NAT)
 241     s->flags |= SNAT_SESSION_FLAG_AFFINITY;
 242   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 243   s->out2in.addr = o2i_addr;
 244   s->out2in.port = o2i_port;
 245   s->out2in.fib_index = o2i_fib_index;
 246   s->in2out.addr = i2o_addr;
 247   s->in2out.port = i2o_port;
 248   s->in2out.fib_index = i2o_fib_index;
 249   s->nat_proto = nat_proto;
 250
 251   /* Add to lookup tables */
 252   init_ed_kv (&kv, o2i_addr, o2i_port, s->ext_host_addr, s->ext_host_port,
 253               o2i_fib_index, ip->protocol, thread_index, s - tsm->sessions);
 254   ctx.now = now;
 255   ctx.thread_index = thread_index;
 256   if (clib_bihash_add_or_overwrite_stale_16_8 (&sm->out2in_ed, &kv,
 257                                                nat44_o2i_ed_is_idle_session_cb,
 258                                                &ctx))
 259     nat_elog_notice ("out2in-ed key add failed");
 260
 261   if (twice_nat == TWICE_NAT || (twice_nat == TWICE_NAT_SELF &&
 262                                  ip->src_address.as_u32 == i2o_addr.as_u32))
 263     {
 264       if (snat_alloc_outside_address_and_port (sm->twice_nat_addresses, 0,
 265                                                thread_index,
 266                                                nat_proto,
 267                                                &s->ext_host_nat_addr,
 268                                                &s->ext_host_nat_port,
 269                                                sm->port_per_thread,
 270                                                tsm->snat_thread_index))
 271         {
 272           b->error = node->errors[NAT_OUT2IN_ED_ERROR_OUT_OF_PORTS];
 273           nat_ed_session_delete (sm, s, thread_index, 1);
 274           if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &kv, 0))
 275             nat_elog_notice ("out2in-ed key del failed");
 276           return 0;
 277         }
 278       s->flags |= SNAT_SESSION_FLAG_TWICE_NAT;
 279       init_ed_kv (&kv, i2o_addr, i2o_port, s->ext_host_nat_addr,
 280                   s->ext_host_nat_port, i2o_fib_index, ip->protocol,
 281                   thread_index, s - tsm->sessions);
 282     }
 283   else
 284     {
 285       init_ed_kv (&kv, i2o_addr, i2o_port, s->ext_host_addr,
 286                   s->ext_host_port, i2o_fib_index, ip->protocol,
 287                   thread_index, s - tsm->sessions);
 288     }
 289   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &kv,
 290                                                nat44_i2o_ed_is_idle_session_cb,
 291                                                &ctx))
 292     nat_elog_notice ("in2out-ed key add failed");
 293
 294   snat_ipfix_logging_nat44_ses_create (thread_index,
 295                                        s->in2out.addr.as_u32,
 296                                        s->out2in.addr.as_u32,
 297                                        s->nat_proto,
 298                                        s->in2out.port,
 299                                        s->out2in.port, s->in2out.fib_index);
 300
 301   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 302                          &s->in2out.addr, s->in2out.port,
 303                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 304                          &s->out2in.addr, s->out2in.port,
 305                          &s->ext_host_addr, s->ext_host_port,
 306                          s->nat_proto, is_twice_nat_session (s));
 307
 308   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 309                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 310                &s->ext_host_nat_addr, s->ext_host_nat_port,
 311                s->nat_proto, s->in2out.fib_index, s->flags, thread_index, 0);
 312
 313   per_vrf_sessions_register_session (s, thread_index);
 314
 315   return s;
 316 }
 317
 318 static int
 319 next_src_nat (snat_main_t * sm, ip4_header_t * ip, u16 src_port,
 320               u16 dst_port, u32 thread_index, u32 rx_fib_index)
 321 {
 322   clib_bihash_kv_16_8_t kv, value;
 323   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 324
 325   init_ed_k (&kv, ip->src_address, src_port, ip->dst_address, dst_port,
 326              rx_fib_index, ip->protocol);
 327   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 328     return 1;
 329
 330   return 0;
 331 }
 332
 333 static void
 334 create_bypass_for_fwd (snat_main_t * sm, vlib_buffer_t * b, ip4_header_t * ip,
 335                        u32 rx_fib_index, u32 thread_index)
 336 {
 337   clib_bihash_kv_16_8_t kv, value;
 338   udp_header_t *udp;
 339   snat_session_t *s = 0;
 340   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 341   vlib_main_t *vm = vlib_get_main ();
 342   f64 now = vlib_time_now (vm);
 343   u16 l_port, r_port;
 344
 345   if (ip->protocol == IP_PROTOCOL_ICMP)
 346     {
 347       if (get_icmp_o2i_ed_key
 348           (b, ip, rx_fib_index, ~0, ~0, 0, &l_port, &r_port, &kv))
 349         return;
 350     }
 351   else
 352     {
 353       if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 354         {
 355           udp = ip4_next_header (ip);
 356           l_port = udp->dst_port;
 357           r_port = udp->src_port;
 358         }
 359       else
 360         {
 361           l_port = 0;
 362           r_port = 0;
 363         }
 364       init_ed_k (&kv, ip->dst_address, l_port, ip->src_address, r_port,
 365                  rx_fib_index, ip->protocol);
 366     }
 367
 368   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 369     {
 370       ASSERT (thread_index == ed_value_get_thread_index (&value));
 371       s =
 372         pool_elt_at_index (tsm->sessions,
 373                            ed_value_get_session_index (&value));
 374     }
 375   else
 376     {
 377       u32 proto;
 378
 379       if (PREDICT_FALSE
 380           (nat44_ed_maximum_sessions_exceeded
 381            (sm, rx_fib_index, thread_index)))
 382         return;
 383
 384       s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
 385       if (!s)
 386         {
 387           nat_elog_warn ("create NAT session failed");
 388           return;
 389         }
 390
 391       proto = ip_proto_to_nat_proto (ip->protocol);
 392
 393       s->ext_host_addr = ip->src_address;
 394       s->ext_host_port = r_port;
 395       s->flags |= SNAT_SESSION_FLAG_FWD_BYPASS;
 396       s->out2in.addr = ip->dst_address;
 397       s->out2in.port = l_port;
 398       s->nat_proto = proto;
 399       if (proto == NAT_PROTOCOL_OTHER)
 400         {
 401           s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 402           s->out2in.port = ip->protocol;
 403         }
 404       s->out2in.fib_index = 0;
 405       s->in2out.addr = s->out2in.addr;
 406       s->in2out.port = s->out2in.port;
 407       s->in2out.fib_index = s->out2in.fib_index;
 408
 409       kv.value = s - tsm->sessions;
 410       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &kv, 1))
 411         nat_elog_notice ("in2out_ed key add failed");
 412
 413       per_vrf_sessions_register_session (s, thread_index);
 414     }
 415
 416   if (ip->protocol == IP_PROTOCOL_TCP)
 417     {
 418       tcp_header_t *tcp = ip4_next_header (ip);
 419       if (nat44_set_tcp_session_state_o2i
 420           (sm, now, s, tcp->flags, tcp->ack_number, tcp->seq_number,
 421            thread_index))
 422         return;
 423     }
 424
 425   /* Accounting */
 426   nat44_session_update_counters (s, now, 0, thread_index);
 427   /* Per-user LRU list maintenance */
 428   nat44_session_update_lru (sm, s, thread_index);
 429 }
 430
 431 static inline void
 432 create_bypass_for_fwd_worker (snat_main_t * sm, vlib_buffer_t * b,
 433                               ip4_header_t * ip, u32 rx_fib_index)
 434 {
 435   ip4_header_t ip_wkr = {
 436     .src_address = ip->dst_address,
 437   };
 438   u32 thread_index = sm->worker_in2out_cb (&ip_wkr, rx_fib_index, 0);
 439
 440   create_bypass_for_fwd (sm, b, ip, rx_fib_index, thread_index);
 441 }
 442
 443 #ifndef CLIB_MARCH_VARIANT
 444 u32
 445 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 446                       u32 thread_index, vlib_buffer_t * b,
 447                       ip4_header_t * ip, ip4_address_t * addr,
 448                       u16 * port, u32 * fib_index, nat_protocol_t * proto,
 449                       void *d, void *e, u8 * dont_translate)
 450 {
 451   u32 next = ~0, sw_if_index, rx_fib_index;
 452   clib_bihash_kv_16_8_t kv, value;
 453   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 454   snat_session_t *s = 0;
 455   u8 is_addr_only, identity_nat;
 456   u16 l_port, r_port;
 457   vlib_main_t *vm = vlib_get_main ();
 458   ip4_address_t sm_addr;
 459   u16 sm_port;
 460   u32 sm_fib_index;
 461   *dont_translate = 0;
 462
 463   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 464   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 465
 466   if (get_icmp_o2i_ed_key
 467       (b, ip, rx_fib_index, ~0, ~0, proto, &l_port, &r_port, &kv))
 468     {
 469       b->error = node->errors[NAT_OUT2IN_ED_ERROR_UNSUPPORTED_PROTOCOL];
 470       next = NAT_NEXT_DROP;
 471       goto out;
 472     }
 473
 474   if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 475     {
 476       /* Try to match static mapping */
 477       if (snat_static_mapping_match
 478           (sm, ip->dst_address, l_port, rx_fib_index,
 479            ip_proto_to_nat_proto (ip->protocol), &sm_addr, &sm_port,
 480            &sm_fib_index, 1, &is_addr_only, 0, 0, 0, &identity_nat))
 481         {
 482           if (!sm->forwarding_enabled)
 483             {
 484               /* Don't NAT packet aimed at the intfc address */
 485               if (PREDICT_FALSE (is_interface_addr (sm, node, sw_if_index,
 486                                                     ip->dst_address.as_u32)))
 487                 {
 488                   *dont_translate = 1;
 489                   goto out;
 490                 }
 491               b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 492               next = NAT_NEXT_DROP;
 493               goto out;
 494             }
 495           else
 496             {
 497               *dont_translate = 1;
 498               if (next_src_nat (sm, ip, l_port, r_port,
 499                                 thread_index, rx_fib_index))
 500                 {
 501                   next = NAT_NEXT_IN2OUT_ED_FAST_PATH;
 502                   goto out;
 503                 }
 504               if (sm->num_workers > 1)
 505                 create_bypass_for_fwd_worker (sm, b, ip, rx_fib_index);
 506               else
 507                 create_bypass_for_fwd (sm, b, ip, rx_fib_index, thread_index);
 508               goto out;
 509             }
 510         }
 511
 512       if (PREDICT_FALSE
 513           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 514            ICMP4_echo_reply
 515            && (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 516                ICMP4_echo_request || !is_addr_only)))
 517         {
 518           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 519           next = NAT_NEXT_DROP;
 520           goto out;
 521         }
 522
 523       if (PREDICT_FALSE (identity_nat))
 524         {
 525           *dont_translate = 1;
 526           goto out;
 527         }
 528
 529       /* Create session initiated by host from external network */
 530       s =
 531         create_session_for_static_mapping_ed (sm, b, sm_addr, sm_port,
 532                                               sm_fib_index, ip->dst_address,
 533                                               l_port, rx_fib_index, *proto,
 534                                               node, rx_fib_index,
 535                                               thread_index, 0, 0,
 536                                               vlib_time_now (vm));
 537
 538       if (!s)
 539         {
 540           next = NAT_NEXT_DROP;
 541           goto out;
 542         }
 543     }
 544   else
 545     {
 546       if (PREDICT_FALSE
 547           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 548            ICMP4_echo_reply
 549            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 550            ICMP4_echo_request
 551            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 552                                            reass.icmp_type_or_tcp_flags)))
 553         {
 554           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 555           next = NAT_NEXT_DROP;
 556           goto out;
 557         }
 558
 559       ASSERT (thread_index == ed_value_get_thread_index (&value));
 560       s =
 561         pool_elt_at_index (tsm->sessions,
 562                            ed_value_get_session_index (&value));
 563     }
 564 out:
 565   if (s)
 566     {
 567       *addr = s->in2out.addr;
 568       *port = s->in2out.port;
 569       *fib_index = s->in2out.fib_index;
 570     }
 571   if (d)
 572     *(snat_session_t **) d = s;
 573   return next;
 574 }
 575 #endif
 576
 577 static snat_session_t *
 578 nat44_ed_out2in_unknown_proto (snat_main_t * sm,
 579                                vlib_buffer_t * b,
 580                                ip4_header_t * ip,
 581                                u32 rx_fib_index,
 582                                u32 thread_index,
 583                                f64 now,
 584                                vlib_main_t * vm, vlib_node_runtime_t * node)
 585 {
 586   clib_bihash_kv_8_8_t kv, value;
 587   clib_bihash_kv_16_8_t s_kv, s_value;
 588   snat_static_mapping_t *m;
 589   u32 old_addr, new_addr;
 590   ip_csum_t sum;
 591   snat_session_t *s;
 592   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 593
 594   old_addr = ip->dst_address.as_u32;
 595
 596   init_ed_k (&s_kv, ip->dst_address, 0, ip->src_address, 0, rx_fib_index,
 597              ip->protocol);
 598
 599   if (!clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
 600     {
 601       ASSERT (thread_index == ed_value_get_thread_index (&s_value));
 602       s =
 603         pool_elt_at_index (tsm->sessions,
 604                            ed_value_get_session_index (&s_value));
 605       new_addr = ip->dst_address.as_u32 = s->in2out.addr.as_u32;
 606     }
 607   else
 608     {
 609       if (PREDICT_FALSE
 610           (nat44_ed_maximum_sessions_exceeded
 611            (sm, rx_fib_index, thread_index)))
 612         {
 613           b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 614           nat_elog_notice ("maximum sessions exceeded");
 615           return 0;
 616         }
 617
 618       init_nat_k (&kv, ip->dst_address, 0, 0, 0);
 619       if (clib_bihash_search_8_8
 620           (&sm->static_mapping_by_external, &kv, &value))
 621         {
 622           b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 623           return 0;
 624         }
 625
 626       m = pool_elt_at_index (sm->static_mappings, value.value);
 627
 628       new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 629
 630       /* Create a new session */
 631       s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
 632       if (!s)
 633         {
 634           b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 635           nat_elog_warn ("create NAT session failed");
 636           return 0;
 637         }
 638
 639       s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 640       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 641       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 642       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 643       s->out2in.addr.as_u32 = old_addr;
 644       s->out2in.fib_index = rx_fib_index;
 645       s->in2out.addr.as_u32 = new_addr;
 646       s->in2out.fib_index = m->fib_index;
 647       s->in2out.port = s->out2in.port = ip->protocol;
 648
 649       /* Add to lookup tables */
 650       s_kv.value = s - tsm->sessions;
 651       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &s_kv, 1))
 652         nat_elog_notice ("out2in key add failed");
 653
 654       init_ed_kv (&s_kv, ip->dst_address, 0, ip->src_address, 0, m->fib_index,
 655                   ip->protocol, thread_index, s - tsm->sessions);
 656       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 657         nat_elog_notice ("in2out key add failed");
 658
 659       per_vrf_sessions_register_session (s, thread_index);
 660     }
 661
 662   /* Update IP checksum */
 663   sum = ip->checksum;
 664   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 665   ip->checksum = ip_csum_fold (sum);
 666
 667   vnet_buffer (b)->sw_if_index[VLIB_TX] = s->in2out.fib_index;
 668
 669   /* Accounting */
 670   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 671                                  thread_index);
 672   /* Per-user LRU list maintenance */
 673   nat44_session_update_lru (sm, s, thread_index);
 674
 675   return s;
 676 }
 677
 678 static inline uword
 679 nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
 680                                           vlib_node_runtime_t * node,
 681                                           vlib_frame_t * frame,
 682                                           int is_multi_worker)
 683 {
 684   u32 n_left_from, *from;
 685   snat_main_t *sm = &snat_main;
 686   f64 now = vlib_time_now (vm);
 687   u32 thread_index = vm->thread_index;
 688   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 689
 690   from = vlib_frame_vector_args (frame);
 691   n_left_from = frame->n_vectors;
 692
 693   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 694   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 695   vlib_get_buffers (vm, from, b, n_left_from);
 696
 697   while (n_left_from > 0)
 698     {
 699       vlib_buffer_t *b0;
 700       u32 sw_if_index0, rx_fib_index0, proto0, old_addr0, new_addr0;
 701       u16 old_port0, new_port0;
 702       ip4_header_t *ip0;
 703       udp_header_t *udp0;
 704       tcp_header_t *tcp0;
 705       snat_session_t *s0 = 0;
 706       clib_bihash_kv_16_8_t kv0, value0;
 707       ip_csum_t sum0;
 708
 709       b0 = *b;
 710       b++;
 711
 712       /* Prefetch next iteration. */
 713       if (PREDICT_TRUE (n_left_from >= 2))
 714         {
 715           vlib_buffer_t *p2;
 716
 717           p2 = *b;
 718
 719           vlib_prefetch_buffer_header (p2, LOAD);
 720
 721           CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
 722         }
 723
 724       next[0] = vnet_buffer2 (b0)->nat.arc_next;
 725
 726       vnet_buffer (b0)->snat.flags = 0;
 727       ip0 = vlib_buffer_get_current (b0);
 728
 729       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 730       rx_fib_index0 =
 731         fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
 732
 733       if (PREDICT_FALSE (ip0->ttl == 1))
 734         {
 735           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 736           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 737                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
 738                                        0);
 739           next[0] = NAT_NEXT_ICMP_ERROR;
 740           goto trace0;
 741         }
 742
 743       udp0 = ip4_next_header (ip0);
 744       tcp0 = (tcp_header_t *) udp0;
 745       proto0 = ip_proto_to_nat_proto (ip0->protocol);
 746
 747       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 748         {
 749           next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 750           goto trace0;
 751         }
 752
 753       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 754         {
 755           next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 756           goto trace0;
 757         }
 758
 759       init_ed_k (&kv0, ip0->dst_address,
 760                  vnet_buffer (b0)->ip.reass.l4_dst_port, ip0->src_address,
 761                  vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
 762                  ip0->protocol);
 763
 764       /* there is a stashed index in vnet_buffer2 from handoff node,
 765        * see if we can use it */
 766       if (is_multi_worker
 767           &&
 768           PREDICT_TRUE (!pool_is_free_index
 769                         (tsm->sessions,
 770                          vnet_buffer2 (b0)->nat.ed_out2in_nat_session_index)))
 771         {
 772           s0 = pool_elt_at_index (tsm->sessions,
 773                                   vnet_buffer2 (b0)->
 774                                   nat.ed_out2in_nat_session_index);
 775           if (PREDICT_TRUE
 776               (s0->out2in.addr.as_u32 == ip0->dst_address.as_u32
 777                && s0->out2in.port == vnet_buffer (b0)->ip.reass.l4_dst_port
 778                && s0->nat_proto == ip_proto_to_nat_proto (ip0->protocol)
 779                && s0->out2in.fib_index == rx_fib_index0
 780                && s0->ext_host_addr.as_u32 == ip0->src_address.as_u32
 781                && s0->ext_host_port ==
 782                vnet_buffer (b0)->ip.reass.l4_src_port))
 783             {
 784               /* yes, this is the droid we're looking for */
 785               goto skip_lookup;
 786             }
 787         }
 788
 789       // lookup for session
 790       if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv0, &value0))
 791         {
 792           // session does not exist go slow path
 793           next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 794           goto trace0;
 795         }
 796       ASSERT (thread_index == ed_value_get_thread_index (&value0));
 797       s0 =
 798         pool_elt_at_index (tsm->sessions,
 799                            ed_value_get_session_index (&value0));
 800
 801     skip_lookup:
 802
 803       if (PREDICT_FALSE (per_vrf_sessions_is_expired (s0, thread_index)))
 804         {
 805           // session is closed, go slow path
 806           nat_free_session_data (sm, s0, thread_index, 0);
 807           nat_ed_session_delete (sm, s0, thread_index, 1);
 808           next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 809           goto trace0;
 810         }
 811
 812       if (s0->tcp_closed_timestamp)
 813         {
 814           if (now >= s0->tcp_closed_timestamp)
 815             {
 816               // session is closed, go slow path, freed in slow path
 817               next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 818             }
 819           else
 820             {
 821               // session in transitory timeout, drop
 822               b0->error = node->errors[NAT_OUT2IN_ED_ERROR_TCP_CLOSED];
 823               next[0] = NAT_NEXT_DROP;
 824             }
 825           goto trace0;
 826         }
 827
 828       // drop if session expired
 829       u64 sess_timeout_time;
 830       sess_timeout_time =
 831         s0->last_heard + (f64) nat44_session_get_timeout (sm, s0);
 832       if (now >= sess_timeout_time)
 833         {
 834           // session is closed, go slow path
 835           nat_free_session_data (sm, s0, thread_index, 0);
 836           nat_ed_session_delete (sm, s0, thread_index, 1);
 837           next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 838           goto trace0;
 839         }
 840
 841       old_addr0 = ip0->dst_address.as_u32;
 842       new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
 843       vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 844
 845       sum0 = ip0->checksum;
 846       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 847                              dst_address);
 848       if (PREDICT_FALSE (is_twice_nat_session (s0)))
 849         sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 850                                s0->ext_host_nat_addr.as_u32, ip4_header_t,
 851                                src_address);
 852       ip0->checksum = ip_csum_fold (sum0);
 853
 854       old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
 855
 856       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 857         {
 858           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 859             {
 860               new_port0 = udp0->dst_port = s0->in2out.port;
 861               sum0 = tcp0->checksum;
 862               sum0 =
 863                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 864                                 dst_address);
 865               sum0 =
 866                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 867                                 length);
 868               if (is_twice_nat_session (s0))
 869                 {
 870                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 871                                          s0->ext_host_nat_addr.as_u32,
 872                                          ip4_header_t, dst_address);
 873                   sum0 =
 874                     ip_csum_update (sum0,
 875                                     vnet_buffer (b0)->ip.reass.l4_src_port,
 876                                     s0->ext_host_nat_port, ip4_header_t,
 877                                     length);
 878                   tcp0->src_port = s0->ext_host_nat_port;
 879                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 880                 }
 881               tcp0->checksum = ip_csum_fold (sum0);
 882             }
 883           vlib_increment_simple_counter (&sm->counters.fastpath.out2in_ed.tcp,
 884                                          thread_index, sw_if_index0, 1);
 885           if (nat44_set_tcp_session_state_o2i
 886               (sm, now, s0, vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags,
 887                vnet_buffer (b0)->ip.reass.tcp_ack_number,
 888                vnet_buffer (b0)->ip.reass.tcp_seq_number, thread_index))
 889             goto trace0;
 890         }
 891       else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
 892                && udp0->checksum)
 893         {
 894           new_port0 = udp0->dst_port = s0->in2out.port;
 895           sum0 = udp0->checksum;
 896           sum0 =
 897             ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 898                             dst_address);
 899           sum0 =
 900             ip_csum_update (sum0, old_port0, new_port0, ip4_header_t, length);
 901           if (PREDICT_FALSE (is_twice_nat_session (s0)))
 902             {
 903               sum0 =
 904                 ip_csum_update (sum0, ip0->src_address.as_u32,
 905                                 s0->ext_host_nat_addr.as_u32, ip4_header_t,
 906                                 dst_address);
 907               sum0 =
 908                 ip_csum_update (sum0, vnet_buffer (b0)->ip.reass.l4_src_port,
 909                                 s0->ext_host_nat_port, ip4_header_t, length);
 910               udp0->src_port = s0->ext_host_nat_port;
 911               ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 912             }
 913           udp0->checksum = ip_csum_fold (sum0);
 914           vlib_increment_simple_counter (&sm->counters.fastpath.out2in_ed.udp,
 915                                          thread_index, sw_if_index0, 1);
 916         }
 917       else
 918         {
 919           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 920             {
 921               new_port0 = udp0->dst_port = s0->in2out.port;
 922               if (PREDICT_FALSE (is_twice_nat_session (s0)))
 923                 {
 924                   udp0->src_port = s0->ext_host_nat_port;
 925                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 926                 }
 927             }
 928           vlib_increment_simple_counter (&sm->counters.fastpath.out2in_ed.udp,
 929                                          thread_index, sw_if_index0, 1);
 930         }
 931
 932       /* Accounting */
 933       nat44_session_update_counters (s0, now,
 934                                      vlib_buffer_length_in_chain (vm, b0),
 935                                      thread_index);
 936       /* Per-user LRU list maintenance */
 937       nat44_session_update_lru (sm, s0, thread_index);
 938
 939     trace0:
 940       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 941                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 942         {
 943           nat44_ed_out2in_trace_t *t =
 944             vlib_add_trace (vm, node, b0, sizeof (*t));
 945           t->sw_if_index = sw_if_index0;
 946           t->next_index = next[0];
 947           t->is_slow_path = 0;
 948
 949           if (s0)
 950             t->session_index = s0 - tsm->sessions;
 951           else
 952             t->session_index = ~0;
 953         }
 954
 955       if (next[0] == NAT_NEXT_DROP)
 956         {
 957           vlib_increment_simple_counter (&sm->counters.fastpath.
 958                                          out2in_ed.drops, thread_index,
 959                                          sw_if_index0, 1);
 960         }
 961
 962       n_left_from--;
 963       next++;
 964     }
 965
 966   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
 967                                frame->n_vectors);
 968   return frame->n_vectors;
 969 }
 970
 971 static inline uword
 972 nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 973                                           vlib_node_runtime_t * node,
 974                                           vlib_frame_t * frame)
 975 {
 976   u32 n_left_from, *from;
 977   snat_main_t *sm = &snat_main;
 978   f64 now = vlib_time_now (vm);
 979   u32 thread_index = vm->thread_index;
 980   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 981
 982   from = vlib_frame_vector_args (frame);
 983   n_left_from = frame->n_vectors;
 984
 985   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 986   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 987   vlib_get_buffers (vm, from, b, n_left_from);
 988
 989   while (n_left_from > 0)
 990     {
 991       vlib_buffer_t *b0;
 992       u32 sw_if_index0, rx_fib_index0, proto0, old_addr0, new_addr0;
 993       u16 old_port0, new_port0;
 994       ip4_header_t *ip0;
 995       udp_header_t *udp0;
 996       tcp_header_t *tcp0;
 997       icmp46_header_t *icmp0;
 998       snat_session_t *s0 = 0;
 999       clib_bihash_kv_16_8_t kv0, value0;
1000       ip_csum_t sum0;
1001       lb_nat_type_t lb_nat0;
1002       twice_nat_type_t twice_nat0;
1003       u8 identity_nat0;
1004       ip4_address_t sm_addr;
1005       u16 sm_port;
1006       u32 sm_fib_index;
1007
1008       b0 = *b;
1009       next[0] = vnet_buffer2 (b0)->nat.arc_next;
1010
1011       vnet_buffer (b0)->snat.flags = 0;
1012       ip0 = vlib_buffer_get_current (b0);
1013
1014       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1015       rx_fib_index0 =
1016         fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
1017
1018       if (PREDICT_FALSE (ip0->ttl == 1))
1019         {
1020           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1021           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1022                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1023                                        0);
1024           next[0] = NAT_NEXT_ICMP_ERROR;
1025           goto trace0;
1026         }
1027
1028       udp0 = ip4_next_header (ip0);
1029       tcp0 = (tcp_header_t *) udp0;
1030       icmp0 = (icmp46_header_t *) udp0;
1031       proto0 = ip_proto_to_nat_proto (ip0->protocol);
1032
1033       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1034         {
1035           s0 =
1036             nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
1037                                            thread_index, now, vm, node);
1038           if (!sm->forwarding_enabled)
1039             {
1040               if (!s0)
1041                 next[0] = NAT_NEXT_DROP;
1042             }
1043           vlib_increment_simple_counter (&sm->counters.slowpath.
1044                                          out2in_ed.other, thread_index,
1045                                          sw_if_index0, 1);
1046           goto trace0;
1047         }
1048
1049       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1050         {
1051           next[0] = icmp_out2in_ed_slow_path
1052             (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1053              next[0], now, thread_index, &s0);
1054           vlib_increment_simple_counter (&sm->counters.slowpath.
1055                                          out2in_ed.icmp, thread_index,
1056                                          sw_if_index0, 1);
1057           goto trace0;
1058         }
1059
1060       init_ed_k (&kv0, ip0->dst_address,
1061                  vnet_buffer (b0)->ip.reass.l4_dst_port, ip0->src_address,
1062                  vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
1063                  ip0->protocol);
1064
1065       s0 = NULL;
1066       if (!clib_bihash_search_16_8 (&sm->out2in_ed, &kv0, &value0))
1067         {
1068           ASSERT (thread_index == ed_value_get_thread_index (&value0));
1069           s0 =
1070             pool_elt_at_index (tsm->sessions,
1071                                ed_value_get_session_index (&value0));
1072
1073           if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
1074             {
1075               nat_free_session_data (sm, s0, thread_index, 0);
1076               nat_ed_session_delete (sm, s0, thread_index, 1);
1077               s0 = NULL;
1078             }
1079         }
1080
1081       if (!s0)
1082         {
1083           /* Try to match static mapping by external address and port,
1084              destination address and port in packet */
1085
1086           if (snat_static_mapping_match
1087               (sm, ip0->dst_address,
1088                vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
1089                proto0, &sm_addr, &sm_port, &sm_fib_index, 1, 0,
1090                &twice_nat0, &lb_nat0, &ip0->src_address, &identity_nat0))
1091             {
1092               /*
1093                * Send DHCP packets to the ipv4 stack, or we won't
1094                * be able to use dhcp client on the outside interface
1095                */
1096               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_UDP
1097                                  && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1098                                      clib_host_to_net_u16
1099                                      (UDP_DST_PORT_dhcp_to_client))))
1100                 {
1101                   goto trace0;
1102                 }
1103
1104               if (!sm->forwarding_enabled)
1105                 {
1106                   b0->error =
1107                     node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1108                   next[0] = NAT_NEXT_DROP;
1109                 }
1110               else
1111                 {
1112                   if (next_src_nat
1113                       (sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
1114                        vnet_buffer (b0)->ip.reass.l4_dst_port,
1115                        thread_index, rx_fib_index0))
1116                     {
1117                       next[0] = NAT_NEXT_IN2OUT_ED_FAST_PATH;
1118                       goto trace0;
1119                     }
1120                   if (sm->num_workers > 1)
1121                     create_bypass_for_fwd_worker (sm, b0, ip0, rx_fib_index0);
1122                   else
1123                     create_bypass_for_fwd (sm, b0, ip0, rx_fib_index0,
1124                                            thread_index);
1125                 }
1126               goto trace0;
1127             }
1128
1129           if (PREDICT_FALSE (identity_nat0))
1130             goto trace0;
1131
1132           if ((proto0 == NAT_PROTOCOL_TCP)
1133               && !tcp_flags_is_init (vnet_buffer (b0)->ip.
1134                                      reass.icmp_type_or_tcp_flags))
1135             {
1136               b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1137               next[0] = NAT_NEXT_DROP;
1138               goto trace0;
1139             }
1140
1141           /* Create session initiated by host from external network */
1142           s0 = create_session_for_static_mapping_ed (sm, b0,
1143                                                      sm_addr, sm_port,
1144                                                      sm_fib_index,
1145                                                      ip0->dst_address,
1146                                                      vnet_buffer (b0)->
1147                                                      ip.reass.l4_dst_port,
1148                                                      rx_fib_index0, proto0,
1149                                                      node, rx_fib_index0,
1150                                                      thread_index, twice_nat0,
1151                                                      lb_nat0, now);
1152           if (!s0)
1153             {
1154               next[0] = NAT_NEXT_DROP;
1155               goto trace0;
1156             }
1157         }
1158
1159       old_addr0 = ip0->dst_address.as_u32;
1160       new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
1161       vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1162
1163       sum0 = ip0->checksum;
1164       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1165                              dst_address);
1166       if (PREDICT_FALSE (is_twice_nat_session (s0)))
1167         sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1168                                s0->ext_host_nat_addr.as_u32, ip4_header_t,
1169                                src_address);
1170       ip0->checksum = ip_csum_fold (sum0);
1171
1172       old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
1173
1174       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1175         {
1176           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1177             {
1178               new_port0 = udp0->dst_port = s0->in2out.port;
1179               sum0 = tcp0->checksum;
1180               sum0 =
1181                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1182                                 dst_address);
1183               sum0 =
1184                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1185                                 length);
1186               if (is_twice_nat_session (s0))
1187                 {
1188                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1189                                          s0->ext_host_nat_addr.as_u32,
1190                                          ip4_header_t, dst_address);
1191                   sum0 =
1192                     ip_csum_update (sum0,
1193                                     vnet_buffer (b0)->ip.reass.l4_src_port,
1194                                     s0->ext_host_nat_port, ip4_header_t,
1195                                     length);
1196                   tcp0->src_port = s0->ext_host_nat_port;
1197                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1198                 }
1199               tcp0->checksum = ip_csum_fold (sum0);
1200             }
1201           vlib_increment_simple_counter (&sm->counters.slowpath.out2in_ed.tcp,
1202                                          thread_index, sw_if_index0, 1);
1203           if (nat44_set_tcp_session_state_o2i
1204               (sm, now, s0, vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags,
1205                vnet_buffer (b0)->ip.reass.tcp_ack_number,
1206                vnet_buffer (b0)->ip.reass.tcp_seq_number, thread_index))
1207             goto trace0;
1208         }
1209       else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1210                && udp0->checksum)
1211         {
1212           new_port0 = udp0->dst_port = s0->in2out.port;
1213           sum0 = udp0->checksum;
1214           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1215                                  dst_address);
1216           sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1217                                  length);
1218           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1219             {
1220               sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1221                                      s0->ext_host_nat_addr.as_u32,
1222                                      ip4_header_t, dst_address);
1223               sum0 =
1224                 ip_csum_update (sum0,
1225                                 vnet_buffer (b0)->ip.reass.l4_src_port,
1226                                 s0->ext_host_nat_port, ip4_header_t, length);
1227               udp0->src_port = s0->ext_host_nat_port;
1228               ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1229             }
1230           udp0->checksum = ip_csum_fold (sum0);
1231           vlib_increment_simple_counter (&sm->counters.slowpath.out2in_ed.udp,
1232                                          thread_index, sw_if_index0, 1);
1233         }
1234       else
1235         {
1236           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1237             {
1238               new_port0 = udp0->dst_port = s0->in2out.port;
1239               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1240                 {
1241                   udp0->src_port = s0->ext_host_nat_port;
1242                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1243                 }
1244             }
1245           vlib_increment_simple_counter (&sm->counters.slowpath.out2in_ed.udp,
1246                                          thread_index, sw_if_index0, 1);
1247         }
1248
1249       /* Accounting */
1250       nat44_session_update_counters (s0, now,
1251                                      vlib_buffer_length_in_chain (vm, b0),
1252                                      thread_index);
1253       /* Per-user LRU list maintenance */
1254       nat44_session_update_lru (sm, s0, thread_index);
1255
1256     trace0:
1257       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1258                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1259         {
1260           nat44_ed_out2in_trace_t *t =
1261             vlib_add_trace (vm, node, b0, sizeof (*t));
1262           t->sw_if_index = sw_if_index0;
1263           t->next_index = next[0];
1264           t->is_slow_path = 1;
1265
1266           if (s0)
1267             t->session_index = s0 - tsm->sessions;
1268           else
1269             t->session_index = ~0;
1270         }
1271
1272       if (next[0] == NAT_NEXT_DROP)
1273         {
1274           vlib_increment_simple_counter (&sm->counters.slowpath.
1275                                          out2in_ed.drops, thread_index,
1276                                          sw_if_index0, 1);
1277         }
1278
1279       n_left_from--;
1280       next++;
1281       b++;
1282     }
1283
1284   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1285                                frame->n_vectors);
1286
1287   return frame->n_vectors;
1288 }
1289
1290 VLIB_NODE_FN (nat44_ed_out2in_node) (vlib_main_t * vm,
1291                                      vlib_node_runtime_t * node,
1292                                      vlib_frame_t * frame)
1293 {
1294   if (snat_main.num_workers > 1)
1295     {
1296       return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame, 1);
1297     }
1298   else
1299     {
1300       return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame, 0);
1301     }
1302 }
1303
1304 /* *INDENT-OFF* */
1305 VLIB_REGISTER_NODE (nat44_ed_out2in_node) = {
1306   .name = "nat44-ed-out2in",
1307   .vector_size = sizeof (u32),
1308   .sibling_of = "nat-default",
1309   .format_trace = format_nat44_ed_out2in_trace,
1310   .type = VLIB_NODE_TYPE_INTERNAL,
1311   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1312   .error_strings = nat_out2in_ed_error_strings,
1313   .runtime_data_bytes = sizeof (snat_runtime_t),
1314 };
1315 /* *INDENT-ON* */
1316
1317 VLIB_NODE_FN (nat44_ed_out2in_slowpath_node) (vlib_main_t * vm,
1318                                               vlib_node_runtime_t * node,
1319                                               vlib_frame_t * frame)
1320 {
1321   return nat44_ed_out2in_slow_path_node_fn_inline (vm, node, frame);
1322 }
1323
1324 /* *INDENT-OFF* */
1325 VLIB_REGISTER_NODE (nat44_ed_out2in_slowpath_node) = {
1326   .name = "nat44-ed-out2in-slowpath",
1327   .vector_size = sizeof (u32),
1328   .sibling_of = "nat-default",
1329   .format_trace = format_nat44_ed_out2in_trace,
1330   .type = VLIB_NODE_TYPE_INTERNAL,
1331   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1332   .error_strings = nat_out2in_ed_error_strings,
1333   .runtime_data_bytes = sizeof (snat_runtime_t),
1334 };
1335 /* *INDENT-ON* */
1336
1337 static u8 *
1338 format_nat_pre_trace (u8 * s, va_list * args)
1339 {
1340   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1341   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1342   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1343   return format (s, "out2in next_index %d arc_next_index %d", t->next_index,
1344                  t->arc_next_index);
1345 }
1346
1347 VLIB_NODE_FN (nat_pre_out2in_node) (vlib_main_t * vm,
1348                                     vlib_node_runtime_t * node,
1349                                     vlib_frame_t * frame)
1350 {
1351   return nat_pre_node_fn_inline (vm, node, frame,
1352                                  NAT_NEXT_OUT2IN_ED_FAST_PATH);
1353 }
1354
1355 /* *INDENT-OFF* */
1356 VLIB_REGISTER_NODE (nat_pre_out2in_node) = {
1357   .name = "nat-pre-out2in",
1358   .vector_size = sizeof (u32),
1359   .sibling_of = "nat-default",
1360   .format_trace = format_nat_pre_trace,
1361   .type = VLIB_NODE_TYPE_INTERNAL,
1362   .n_errors = 0,
1363  };
1364 /* *INDENT-ON* */
1365
1366 /*
1367  * fd.io coding-style-patch-verification: ON
1368  *
1369  * Local Variables:
1370  * eval: (c-set-style "gnu")
1371  * End:
1372  */