src/plugins/nat/in2out_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 inside to outside 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
  35 static char *nat_in2out_ed_error_strings[] = {
  36 #define _(sym,string) string,
  37   foreach_nat_in2out_ed_error
  38 #undef _
  39 };
  40
  41 typedef struct
  42 {
  43   u32 sw_if_index;
  44   u32 next_index;
  45   u32 session_index;
  46   u32 is_slow_path;
  47 } nat_in2out_ed_trace_t;
  48
  49 static u8 *
  50 format_nat_in2out_ed_trace (u8 * s, va_list * args)
  51 {
  52   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  53   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  54   nat_in2out_ed_trace_t *t = va_arg (*args, nat_in2out_ed_trace_t *);
  55   char *tag;
  56
  57   tag =
  58     t->is_slow_path ? "NAT44_IN2OUT_ED_SLOW_PATH" :
  59     "NAT44_IN2OUT_ED_FAST_PATH";
  60
  61   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  62               t->sw_if_index, t->next_index, t->session_index);
  63
  64   return s;
  65 }
  66
  67 #ifndef CLIB_MARCH_VARIANT
  68 int
  69 nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  70 {
  71   snat_main_t *sm = &snat_main;
  72   nat44_is_idle_session_ctx_t *ctx = arg;
  73   snat_session_t *s;
  74   u64 sess_timeout_time;
  75   nat_ed_ses_key_t ed_key;
  76   clib_bihash_kv_16_8_t ed_kv;
  77   int i;
  78   snat_address_t *a;
  79   snat_session_key_t key;
  80   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
  81                                                        ctx->thread_index);
  82
  83   s = pool_elt_at_index (tsm->sessions, kv->value);
  84   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
  85   if (ctx->now >= sess_timeout_time)
  86     {
  87       if (is_fwd_bypass_session (s))
  88         goto delete;
  89
  90       ed_key.l_addr = s->out2in.addr;
  91       ed_key.r_addr = s->ext_host_addr;
  92       ed_key.fib_index = s->out2in.fib_index;
  93       if (snat_is_unk_proto_session (s))
  94         {
  95           ed_key.proto = s->in2out.port;
  96           ed_key.r_port = 0;
  97           ed_key.l_port = 0;
  98         }
  99       else
 100         {
 101           ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
 102           ed_key.l_port = s->out2in.port;
 103           ed_key.r_port = s->ext_host_port;
 104         }
 105       ed_kv.key[0] = ed_key.as_u64[0];
 106       ed_kv.key[1] = ed_key.as_u64[1];
 107       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &ed_kv, 0))
 108         nat_elog_warn ("out2in_ed key del failed");
 109
 110       if (snat_is_unk_proto_session (s))
 111         goto delete;
 112
 113       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 114                                            s->in2out.addr.as_u32,
 115                                            s->out2in.addr.as_u32,
 116                                            s->in2out.protocol,
 117                                            s->in2out.port,
 118                                            s->out2in.port,
 119                                            s->in2out.fib_index);
 120
 121       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 122                              &s->in2out.addr, s->in2out.port,
 123                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 124                              &s->out2in.addr, s->out2in.port,
 125                              &s->ext_host_addr, s->ext_host_port,
 126                              s->in2out.protocol, is_twice_nat_session (s));
 127
 128       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 129                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 130                    ctx->thread_index);
 131
 132       if (is_twice_nat_session (s))
 133         {
 134           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 135             {
 136               key.protocol = s->in2out.protocol;
 137               key.port = s->ext_host_nat_port;
 138               a = sm->twice_nat_addresses + i;
 139               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 140                 {
 141                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 142                                                       ctx->thread_index,
 143                                                       &key);
 144                   break;
 145                 }
 146             }
 147         }
 148
 149       if (snat_is_session_static (s))
 150         goto delete;
 151
 152       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 153                                           &s->out2in);
 154     delete:
 155       nat44_delete_session (sm, s, ctx->thread_index);
 156       return 1;
 157     }
 158
 159   return 0;
 160 }
 161 #endif
 162
 163 static inline u32
 164 icmp_in2out_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 165                           ip4_header_t * ip0, icmp46_header_t * icmp0,
 166                           u32 sw_if_index0, u32 rx_fib_index0,
 167                           vlib_node_runtime_t * node, u32 next0, f64 now,
 168                           u32 thread_index, snat_session_t ** p_s0)
 169 {
 170   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 171                        next0, thread_index, p_s0, 0);
 172   snat_session_t *s0 = *p_s0;
 173   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
 174     {
 175       /* Accounting */
 176       nat44_session_update_counters (s0, now,
 177                                      vlib_buffer_length_in_chain
 178                                      (sm->vlib_main, b0), thread_index);
 179       /* Per-user LRU list maintenance */
 180       nat44_session_update_lru (sm, s0, thread_index);
 181     }
 182   return next0;
 183 }
 184
 185 static u32
 186 slow_path_ed (snat_main_t * sm,
 187               vlib_buffer_t * b,
 188               u32 rx_fib_index,
 189               clib_bihash_kv_16_8_t * kv,
 190               snat_session_t ** sessionp,
 191               vlib_node_runtime_t * node, u32 next, u32 thread_index, f64 now)
 192 {
 193   snat_session_t *s = 0;
 194   snat_user_t *u;
 195   snat_session_key_t key0, key1;
 196   lb_nat_type_t lb = 0, is_sm = 0;
 197   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 198   nat_ed_ses_key_t *key = (nat_ed_ses_key_t *) kv->key;
 199   u32 proto = ip_proto_to_snat_proto (key->proto);
 200   nat_outside_fib_t *outside_fib;
 201   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 202   u8 identity_nat;
 203   fib_prefix_t pfx = {
 204     .fp_proto = FIB_PROTOCOL_IP4,
 205     .fp_len = 32,
 206     .fp_addr = {
 207                 .ip4.as_u32 = key->r_addr.as_u32,
 208                 },
 209   };
 210   nat44_is_idle_session_ctx_t ctx;
 211
 212   u32 cleared = 0;
 213
 214   if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 215     {
 216       if (PREDICT_FALSE
 217           (!(cleared = nat44_users_cleanup (thread_index, now))))
 218         {
 219           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 220           nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 221           nat_elog_notice ("maximum sessions exceeded");
 222           return NAT_NEXT_DROP;
 223         }
 224     }
 225
 226   key0.addr = key->l_addr;
 227   key0.port = key->l_port;
 228   key1.protocol = key0.protocol = proto;
 229   key0.fib_index = rx_fib_index;
 230   key1.fib_index = sm->outside_fib_index;
 231
 232   /* First try to match static mapping by local address and port */
 233   if (snat_static_mapping_match
 234       (sm, key0, &key1, 0, 0, 0, &lb, 0, &identity_nat))
 235     {
 236       /* Try to create dynamic translation */
 237       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index,
 238                                                thread_index, &key1,
 239                                                sm->port_per_thread,
 240                                                tsm->snat_thread_index))
 241         {
 242           if (cleared || !nat44_out_of_ports_cleanup (thread_index, now) ||
 243               snat_alloc_outside_address_and_port (sm->addresses,
 244                                                    rx_fib_index, thread_index,
 245                                                    &key1, sm->port_per_thread,
 246                                                    tsm->snat_thread_index))
 247             {
 248               nat_elog_notice ("addresses exhausted");
 249               b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 250               return NAT_NEXT_DROP;
 251             }
 252         }
 253     }
 254   else
 255     {
 256       if (PREDICT_FALSE (identity_nat))
 257         {
 258           *sessionp = s;
 259           return next;
 260         }
 261       is_sm = 1;
 262     }
 263
 264   if (PREDICT_TRUE (proto == SNAT_PROTOCOL_TCP))
 265     {
 266       if (PREDICT_FALSE
 267           (!tcp_flags_is_init
 268            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 269         {
 270           b->error = node->errors[NAT_IN2OUT_ED_ERROR_NON_SYN];
 271           if (!is_sm)
 272             snat_free_outside_address_and_port (sm->addresses,
 273                                                 thread_index, &key1);
 274           return NAT_NEXT_DROP;
 275         }
 276     }
 277
 278   u = nat_user_get_or_create (sm, &key->l_addr, rx_fib_index, thread_index);
 279   if (!u)
 280     {
 281       nat_elog_warn ("create NAT user failed");
 282       if (!is_sm)
 283         snat_free_outside_address_and_port (sm->addresses,
 284                                             thread_index, &key1);
 285       return NAT_NEXT_DROP;
 286     }
 287
 288   s = nat_ed_session_alloc (sm, u, thread_index, now);
 289   if (!s)
 290     {
 291       nat44_delete_user_with_no_session (sm, u, thread_index);
 292       nat_elog_warn ("create NAT session failed");
 293       if (!is_sm)
 294         snat_free_outside_address_and_port (sm->addresses,
 295                                             thread_index, &key1);
 296       return NAT_NEXT_DROP;
 297     }
 298
 299   user_session_increment (sm, u, is_sm);
 300   if (is_sm)
 301     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 302   if (lb)
 303     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 304   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 305   s->ext_host_addr = key->r_addr;
 306   s->ext_host_port = key->r_port;
 307   s->in2out = key0;
 308   s->out2in = key1;
 309   s->out2in.protocol = key0.protocol;
 310
 311   switch (vec_len (sm->outside_fibs))
 312     {
 313     case 0:
 314       s->out2in.fib_index = sm->outside_fib_index;
 315       break;
 316     case 1:
 317       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 318       break;
 319     default:
 320       /* *INDENT-OFF* */
 321       vec_foreach (outside_fib, sm->outside_fibs)
 322        {
 323           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 324           if (FIB_NODE_INDEX_INVALID != fei)
 325             {
 326               if (fib_entry_get_resolving_interface (fei) != ~0)
 327                 {
 328                   s->out2in.fib_index = outside_fib->fib_index;
 329                   break;
 330                 }
 331             }
 332         }
 333       /* *INDENT-ON* */
 334       break;
 335     }
 336
 337   /* Add to lookup tables */
 338   kv->value = s - tsm->sessions;
 339   ctx.now = now;
 340   ctx.thread_index = thread_index;
 341   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, kv,
 342                                                nat44_i2o_ed_is_idle_session_cb,
 343                                                &ctx))
 344     nat_elog_notice ("in2out-ed key add failed");
 345
 346   make_ed_kv (kv, &key1.addr, &key->r_addr, key->proto, s->out2in.fib_index,
 347               key1.port, key->r_port);
 348   kv->value = s - tsm->sessions;
 349   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, kv,
 350                                                nat44_o2i_ed_is_idle_session_cb,
 351                                                &ctx))
 352     nat_elog_notice ("out2in-ed key add failed");
 353
 354   *sessionp = s;
 355
 356   /* log NAT event */
 357   snat_ipfix_logging_nat44_ses_create (thread_index,
 358                                        s->in2out.addr.as_u32,
 359                                        s->out2in.addr.as_u32,
 360                                        s->in2out.protocol,
 361                                        s->in2out.port,
 362                                        s->out2in.port, s->in2out.fib_index);
 363
 364   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 365                          &s->in2out.addr, s->in2out.port,
 366                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 367                          &s->out2in.addr, s->out2in.port,
 368                          &s->ext_host_addr, s->ext_host_port,
 369                          s->in2out.protocol, 0);
 370
 371   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 372                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 373                &s->ext_host_nat_addr, s->ext_host_nat_port,
 374                s->in2out.protocol, s->in2out.fib_index, s->flags,
 375                thread_index, 0);
 376
 377   return next;
 378 }
 379
 380 static_always_inline int
 381 nat44_ed_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 382                         u32 sw_if_index, ip4_header_t * ip, u32 proto,
 383                         u32 rx_fib_index, u32 thread_index)
 384 {
 385   udp_header_t *udp = ip4_next_header (ip);
 386   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 387   clib_bihash_kv_16_8_t kv, value;
 388   snat_session_key_t key0, key1;
 389
 390   make_ed_kv (&kv, &ip->dst_address, &ip->src_address, ip->protocol,
 391               sm->outside_fib_index, udp->dst_port, udp->src_port);
 392
 393   /* NAT packet aimed at external address if */
 394   /* has active sessions */
 395   if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 396     {
 397       key0.addr = ip->dst_address;
 398       key0.port = udp->dst_port;
 399       key0.protocol = proto;
 400       key0.fib_index = sm->outside_fib_index;
 401       /* or is static mappings */
 402       if (!snat_static_mapping_match (sm, key0, &key1, 1, 0, 0, 0, 0, 0))
 403         return 0;
 404     }
 405   else
 406     return 0;
 407
 408   if (sm->forwarding_enabled)
 409     return 1;
 410
 411   return snat_not_translate_fast (sm, node, sw_if_index, ip, proto,
 412                                   rx_fib_index);
 413 }
 414
 415 static_always_inline int
 416 nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
 417                                       u32 thread_index, f64 now,
 418                                       vlib_main_t * vm, vlib_buffer_t * b)
 419 {
 420   nat_ed_ses_key_t key;
 421   clib_bihash_kv_16_8_t kv, value;
 422   snat_session_t *s = 0;
 423   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 424
 425   if (!sm->forwarding_enabled)
 426     return 0;
 427
 428   if (ip->protocol == IP_PROTOCOL_ICMP)
 429     {
 430       key.as_u64[0] = key.as_u64[1] = 0;
 431       if (get_icmp_i2o_ed_key (b, ip, &key))
 432         return 0;
 433       key.fib_index = 0;
 434       kv.key[0] = key.as_u64[0];
 435       kv.key[1] = key.as_u64[1];
 436     }
 437   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 438     {
 439       make_ed_kv (&kv, &ip->src_address, &ip->dst_address, ip->protocol, 0,
 440                   vnet_buffer (b)->ip.reass.l4_src_port,
 441                   vnet_buffer (b)->ip.reass.l4_dst_port);
 442     }
 443   else
 444     {
 445       make_ed_kv (&kv, &ip->src_address, &ip->dst_address, ip->protocol, 0, 0,
 446                   0);
 447     }
 448
 449   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 450     {
 451       s = pool_elt_at_index (tsm->sessions, value.value);
 452       if (is_fwd_bypass_session (s))
 453         {
 454           if (ip->protocol == IP_PROTOCOL_TCP)
 455             {
 456               if (nat44_set_tcp_session_state_i2o (sm, s, b, thread_index))
 457                 return 1;
 458             }
 459           /* Accounting */
 460           nat44_session_update_counters (s, now,
 461                                          vlib_buffer_length_in_chain (vm, b),
 462                                          thread_index);
 463           /* Per-user LRU list maintenance */
 464           nat44_session_update_lru (sm, s, thread_index);
 465           return 1;
 466         }
 467       else
 468         return 0;
 469     }
 470
 471   return 0;
 472 }
 473
 474 static_always_inline int
 475 nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
 476                                        u8 proto, u16 src_port, u16 dst_port,
 477                                        u32 thread_index, u32 rx_sw_if_index,
 478                                        u32 tx_sw_if_index)
 479 {
 480   clib_bihash_kv_16_8_t kv, value;
 481   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 482   snat_interface_t *i;
 483   snat_session_t *s;
 484   u32 rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (rx_sw_if_index);
 485   u32 tx_fib_index = ip4_fib_table_get_index_for_sw_if_index (tx_sw_if_index);
 486
 487   /* src NAT check */
 488   make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto, tx_fib_index,
 489               src_port, dst_port);
 490   if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 491     {
 492       s = pool_elt_at_index (tsm->sessions, value.value);
 493       if (nat44_is_ses_closed (s))
 494         {
 495           nat_free_session_data (sm, s, thread_index, 0);
 496           nat44_delete_session (sm, s, thread_index);
 497         }
 498       else
 499         s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
 500       return 1;
 501     }
 502
 503   /* dst NAT check */
 504   make_ed_kv (&kv, &ip->dst_address, &ip->src_address, proto, rx_fib_index,
 505               dst_port, src_port);
 506   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 507     {
 508       s = pool_elt_at_index (tsm->sessions, value.value);
 509       if (is_fwd_bypass_session (s))
 510         return 0;
 511
 512       /* hairpinning */
 513       /* *INDENT-OFF* */
 514       pool_foreach (i, sm->output_feature_interfaces,
 515       ({
 516         if ((nat_interface_is_inside (i)) && (rx_sw_if_index == i->sw_if_index))
 517            return 0;
 518       }));
 519       /* *INDENT-ON* */
 520       return 1;
 521     }
 522
 523   return 0;
 524 }
 525
 526 #ifndef CLIB_MARCH_VARIANT
 527 u32
 528 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 529                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 530                       u8 * p_proto, snat_session_key_t * p_value,
 531                       u8 * p_dont_translate, void *d, void *e)
 532 {
 533   u32 sw_if_index;
 534   u32 rx_fib_index;
 535   nat_ed_ses_key_t key;
 536   snat_session_t *s = 0;
 537   u8 dont_translate = 0;
 538   clib_bihash_kv_16_8_t kv, value;
 539   u32 next = ~0;
 540   int err;
 541   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 542
 543   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 544   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 545
 546   key.as_u64[0] = key.as_u64[1] = 0;
 547   err = get_icmp_i2o_ed_key (b, ip, &key);
 548   if (err != 0)
 549     {
 550       b->error = node->errors[err];
 551       next = NAT_NEXT_DROP;
 552       goto out;
 553     }
 554   key.fib_index = rx_fib_index;
 555
 556   kv.key[0] = key.as_u64[0];
 557   kv.key[1] = key.as_u64[1];
 558
 559   if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 560     {
 561       if (vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0)
 562         {
 563           if (PREDICT_FALSE
 564               (nat44_ed_not_translate_output_feature
 565                (sm, ip, key.proto, key.l_port, key.r_port, thread_index,
 566                 sw_if_index, vnet_buffer (b)->sw_if_index[VLIB_TX])))
 567             {
 568               dont_translate = 1;
 569               goto out;
 570             }
 571         }
 572       else
 573         {
 574           if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
 575                                                      ip, SNAT_PROTOCOL_ICMP,
 576                                                      rx_fib_index,
 577                                                      thread_index)))
 578             {
 579               dont_translate = 1;
 580               goto out;
 581             }
 582         }
 583
 584       if (PREDICT_FALSE
 585           (icmp_type_is_error_message
 586            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 587         {
 588           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 589           next = NAT_NEXT_DROP;
 590           goto out;
 591         }
 592
 593       next = slow_path_ed (sm, b, rx_fib_index, &kv, &s, node, next,
 594                            thread_index, vlib_time_now (sm->vlib_main));
 595
 596       if (PREDICT_FALSE (next == NAT_NEXT_DROP))
 597         goto out;
 598
 599       if (!s)
 600         {
 601           dont_translate = 1;
 602           goto out;
 603         }
 604     }
 605   else
 606     {
 607       if (PREDICT_FALSE
 608           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 609            ICMP4_echo_request
 610            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 611            ICMP4_echo_reply
 612            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 613                                            reass.icmp_type_or_tcp_flags)))
 614         {
 615           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 616           next = NAT_NEXT_DROP;
 617           goto out;
 618         }
 619
 620       s = pool_elt_at_index (tsm->sessions, value.value);
 621     }
 622
 623   *p_proto = ip_proto_to_snat_proto (key.proto);
 624 out:
 625   if (s)
 626     *p_value = s->out2in;
 627   *p_dont_translate = dont_translate;
 628   if (d)
 629     *(snat_session_t **) d = s;
 630   return next;
 631 }
 632 #endif
 633
 634 static snat_session_t *
 635 nat44_ed_in2out_unknown_proto (snat_main_t * sm,
 636                                vlib_buffer_t * b,
 637                                ip4_header_t * ip,
 638                                u32 rx_fib_index,
 639                                u32 thread_index,
 640                                f64 now,
 641                                vlib_main_t * vm, vlib_node_runtime_t * node)
 642 {
 643   clib_bihash_kv_8_8_t kv, value;
 644   clib_bihash_kv_16_8_t s_kv, s_value;
 645   snat_static_mapping_t *m;
 646   u32 old_addr, new_addr = 0;
 647   ip_csum_t sum;
 648   snat_user_t *u;
 649   dlist_elt_t *head, *elt;
 650   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 651   u32 elt_index, head_index, ses_index;
 652   snat_session_t *s;
 653   u32 outside_fib_index = sm->outside_fib_index;
 654   int i;
 655   u8 is_sm = 0;
 656   nat_outside_fib_t *outside_fib;
 657   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 658   fib_prefix_t pfx = {
 659     .fp_proto = FIB_PROTOCOL_IP4,
 660     .fp_len = 32,
 661     .fp_addr = {
 662                 .ip4.as_u32 = ip->dst_address.as_u32,
 663                 },
 664   };
 665
 666   switch (vec_len (sm->outside_fibs))
 667     {
 668     case 0:
 669       outside_fib_index = sm->outside_fib_index;
 670       break;
 671     case 1:
 672       outside_fib_index = sm->outside_fibs[0].fib_index;
 673       break;
 674     default:
 675       /* *INDENT-OFF* */
 676       vec_foreach (outside_fib, sm->outside_fibs)
 677         {
 678           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 679           if (FIB_NODE_INDEX_INVALID != fei)
 680             {
 681               if (fib_entry_get_resolving_interface (fei) != ~0)
 682                 {
 683                   outside_fib_index = outside_fib->fib_index;
 684                   break;
 685                 }
 686             }
 687         }
 688       /* *INDENT-ON* */
 689       break;
 690     }
 691   old_addr = ip->src_address.as_u32;
 692
 693   make_ed_kv (&s_kv, &ip->src_address, &ip->dst_address, ip->protocol,
 694               rx_fib_index, 0, 0);
 695
 696   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &s_kv, &s_value))
 697     {
 698       s = pool_elt_at_index (tsm->sessions, s_value.value);
 699       new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 700     }
 701   else
 702     {
 703       if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 704         {
 705           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 706           nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 707           nat_elog_notice ("maximum sessions exceeded");
 708           return 0;
 709         }
 710
 711       u = nat_user_get_or_create (sm, &ip->src_address, rx_fib_index,
 712                                   thread_index);
 713       if (!u)
 714         {
 715           nat_elog_warn ("create NAT user failed");
 716           return 0;
 717         }
 718
 719       make_sm_kv (&kv, &ip->src_address, 0, rx_fib_index, 0);
 720
 721       /* Try to find static mapping first */
 722       if (!clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 723         {
 724           m = pool_elt_at_index (sm->static_mappings, value.value);
 725           new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 726           is_sm = 1;
 727           goto create_ses;
 728         }
 729       /* Fallback to 3-tuple key */
 730       else
 731         {
 732           /* Choose same out address as for TCP/UDP session to same destination */
 733           head_index = u->sessions_per_user_list_head_index;
 734           head = pool_elt_at_index (tsm->list_pool, head_index);
 735           elt_index = head->next;
 736           if (PREDICT_FALSE (elt_index == ~0))
 737             ses_index = ~0;
 738           else
 739             {
 740               elt = pool_elt_at_index (tsm->list_pool, elt_index);
 741               ses_index = elt->value;
 742             }
 743
 744           while (ses_index != ~0)
 745             {
 746               s = pool_elt_at_index (tsm->sessions, ses_index);
 747               elt_index = elt->next;
 748               elt = pool_elt_at_index (tsm->list_pool, elt_index);
 749               ses_index = elt->value;
 750
 751               if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
 752                 {
 753                   new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 754
 755                   make_ed_kv (&s_kv, &s->out2in.addr, &ip->dst_address,
 756                               ip->protocol, outside_fib_index, 0, 0);
 757                   if (clib_bihash_search_16_8
 758                       (&tsm->out2in_ed, &s_kv, &s_value))
 759                     goto create_ses;
 760
 761                   break;
 762                 }
 763             }
 764
 765           for (i = 0; i < vec_len (sm->addresses); i++)
 766             {
 767               make_ed_kv (&s_kv, &sm->addresses[i].addr, &ip->dst_address,
 768                           ip->protocol, outside_fib_index, 0, 0);
 769               if (clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
 770                 {
 771                   new_addr = ip->src_address.as_u32 =
 772                     sm->addresses[i].addr.as_u32;
 773                   goto create_ses;
 774                 }
 775             }
 776           return 0;
 777         }
 778
 779     create_ses:
 780       s = nat_ed_session_alloc (sm, u, thread_index, now);
 781       if (!s)
 782         {
 783           nat44_delete_user_with_no_session (sm, u, thread_index);
 784           nat_elog_warn ("create NAT session failed");
 785           return 0;
 786         }
 787
 788       s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
 789       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 790       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 791       s->out2in.addr.as_u32 = new_addr;
 792       s->out2in.fib_index = outside_fib_index;
 793       s->in2out.addr.as_u32 = old_addr;
 794       s->in2out.fib_index = rx_fib_index;
 795       s->in2out.port = s->out2in.port = ip->protocol;
 796       if (is_sm)
 797         s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 798       user_session_increment (sm, u, is_sm);
 799
 800       /* Add to lookup tables */
 801       make_ed_kv (&s_kv, &s->in2out.addr, &ip->dst_address, ip->protocol,
 802                   rx_fib_index, 0, 0);
 803       s_kv.value = s - tsm->sessions;
 804       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 805         nat_elog_notice ("in2out key add failed");
 806
 807       make_ed_kv (&s_kv, &s->out2in.addr, &ip->dst_address, ip->protocol,
 808                   outside_fib_index, 0, 0);
 809       s_kv.value = s - tsm->sessions;
 810       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
 811         nat_elog_notice ("out2in key add failed");
 812     }
 813
 814   /* Update IP checksum */
 815   sum = ip->checksum;
 816   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 817   ip->checksum = ip_csum_fold (sum);
 818
 819   /* Accounting */
 820   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 821                                  thread_index);
 822   /* Per-user LRU list maintenance */
 823   nat44_session_update_lru (sm, s, thread_index);
 824
 825   /* Hairpinning */
 826   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 827     nat44_ed_hairpinning_unknown_proto (sm, b, ip);
 828
 829   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 830     vnet_buffer (b)->sw_if_index[VLIB_TX] = outside_fib_index;
 831
 832   return s;
 833 }
 834
 835 static inline uword
 836 nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 837                                           vlib_node_runtime_t * node,
 838                                           vlib_frame_t * frame,
 839                                           int is_output_feature)
 840 {
 841   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 842   nat_next_t next_index;
 843   snat_main_t *sm = &snat_main;
 844   f64 now = vlib_time_now (vm);
 845   u32 thread_index = vm->thread_index;
 846   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 847   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 848     0, def_slow;
 849
 850   def_slow = is_output_feature ? NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH :
 851     NAT_NEXT_IN2OUT_ED_SLOW_PATH;
 852
 853   stats_node_index = sm->ed_in2out_node_index;
 854
 855   from = vlib_frame_vector_args (frame);
 856   n_left_from = frame->n_vectors;
 857   next_index = node->cached_next_index;
 858
 859   while (n_left_from > 0)
 860     {
 861       u32 n_left_to_next;
 862
 863       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 864
 865       while (n_left_from > 0 && n_left_to_next > 0)
 866         {
 867           u32 bi0;
 868           vlib_buffer_t *b0;
 869           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
 870             new_addr0, old_addr0;
 871           u16 old_port0, new_port0;
 872           ip4_header_t *ip0;
 873           udp_header_t *udp0;
 874           tcp_header_t *tcp0;
 875           snat_session_t *s0 = 0;
 876           clib_bihash_kv_16_8_t kv0, value0;
 877           ip_csum_t sum0;
 878
 879           /* speculatively enqueue b0 to the current next frame */
 880           bi0 = from[0];
 881           to_next[0] = bi0;
 882           from += 1;
 883           to_next += 1;
 884           n_left_from -= 1;
 885           n_left_to_next -= 1;
 886
 887           b0 = vlib_get_buffer (vm, bi0);
 888
 889           if (is_output_feature)
 890             {
 891               vnet_feature_next (&nat_buffer_opaque (b0)->arc_next, b0);
 892               iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 893             }
 894
 895           next0 = nat_buffer_opaque (b0)->arc_next;
 896
 897           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 898                                   iph_offset0);
 899
 900           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 901           rx_fib_index0 =
 902             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 903                                                  sw_if_index0);
 904
 905           if (PREDICT_FALSE (ip0->ttl == 1))
 906             {
 907               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 908               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 909                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 910                                            0);
 911               next0 = NAT_NEXT_ICMP_ERROR;
 912               goto trace0;
 913             }
 914
 915           udp0 = ip4_next_header (ip0);
 916           tcp0 = (tcp_header_t *) udp0;
 917           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 918
 919           if (PREDICT_FALSE (proto0 == ~0))
 920             {
 921               next0 = def_slow;
 922               goto trace0;
 923             }
 924
 925           if (is_output_feature)
 926             {
 927               if (PREDICT_FALSE (nat_not_translate_output_feature_fwd
 928                                  (sm, ip0, thread_index, now, vm, b0)))
 929                 goto trace0;
 930             }
 931
 932           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 933             {
 934               next0 = def_slow;
 935               goto trace0;
 936             }
 937
 938           make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
 939                       ip0->protocol, rx_fib_index0,
 940                       vnet_buffer (b0)->ip.reass.l4_src_port,
 941                       vnet_buffer (b0)->ip.reass.l4_dst_port);
 942
 943           // lookup for session
 944           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
 945             {
 946               // session does not exist go slow path
 947               next0 = def_slow;
 948               goto trace0;
 949             }
 950           s0 = pool_elt_at_index (tsm->sessions, value0.value);
 951
 952           // drop if session expired
 953           u64 sess_timeout_time;
 954           sess_timeout_time = s0->last_heard +
 955             (f64) nat44_session_get_timeout (sm, s0);
 956           if (now >= sess_timeout_time)
 957             {
 958               // delete session
 959               nat_free_session_data (sm, s0, thread_index, 0);
 960               nat44_delete_session (sm, s0, thread_index);
 961
 962               next0 = NAT_NEXT_DROP;
 963               goto trace0;
 964             }
 965           //
 966
 967           b0->flags |= VNET_BUFFER_F_IS_NATED;
 968
 969           if (!is_output_feature)
 970             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
 971
 972           old_addr0 = ip0->src_address.as_u32;
 973           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
 974           sum0 = ip0->checksum;
 975           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 976                                  src_address);
 977           if (PREDICT_FALSE (is_twice_nat_session (s0)))
 978             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
 979                                    s0->ext_host_addr.as_u32, ip4_header_t,
 980                                    dst_address);
 981           ip0->checksum = ip_csum_fold (sum0);
 982
 983           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
 984
 985           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
 986             {
 987               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 988                 {
 989                   new_port0 = udp0->src_port = s0->out2in.port;
 990                   sum0 = tcp0->checksum;
 991                   sum0 =
 992                     ip_csum_update (sum0, old_addr0, new_addr0,
 993                                     ip4_header_t, dst_address);
 994                   sum0 =
 995                     ip_csum_update (sum0, old_port0, new_port0,
 996                                     ip4_header_t, length);
 997                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
 998                     {
 999                       sum0 =
1000                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1001                                         s0->ext_host_addr.as_u32,
1002                                         ip4_header_t, dst_address);
1003                       sum0 =
1004                         ip_csum_update (sum0,
1005                                         vnet_buffer (b0)->ip.
1006                                         reass.l4_dst_port, s0->ext_host_port,
1007                                         ip4_header_t, length);
1008                       tcp0->dst_port = s0->ext_host_port;
1009                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1010                     }
1011                   mss_clamping (sm, tcp0, &sum0);
1012                   tcp0->checksum = ip_csum_fold (sum0);
1013                 }
1014               tcp_packets++;
1015               if (nat44_set_tcp_session_state_i2o (sm, s0, b0, thread_index))
1016                 goto trace0;
1017             }
1018           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1019                    && udp0->checksum)
1020             {
1021               new_port0 = udp0->src_port = s0->out2in.port;
1022               sum0 = udp0->checksum;
1023               sum0 =
1024                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1025                                 dst_address);
1026               sum0 =
1027                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1028                                 length);
1029               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1030                 {
1031                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1032                                          s0->ext_host_addr.as_u32,
1033                                          ip4_header_t, dst_address);
1034                   sum0 =
1035                     ip_csum_update (sum0,
1036                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1037                                     s0->ext_host_port, ip4_header_t, length);
1038                   udp0->dst_port = s0->ext_host_port;
1039                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1040                 }
1041               udp0->checksum = ip_csum_fold (sum0);
1042               udp_packets++;
1043             }
1044           else
1045             {
1046               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1047                 {
1048                   new_port0 = udp0->src_port = s0->out2in.port;
1049                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1050                     {
1051                       udp0->dst_port = s0->ext_host_port;
1052                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1053                     }
1054                   udp_packets++;
1055                 }
1056             }
1057
1058           /* Accounting */
1059           nat44_session_update_counters (s0, now,
1060                                          vlib_buffer_length_in_chain
1061                                          (vm, b0), thread_index);
1062           /* Per-user LRU list maintenance */
1063           nat44_session_update_lru (sm, s0, thread_index);
1064
1065         trace0:
1066           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1067                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1068             {
1069               nat_in2out_ed_trace_t *t =
1070                 vlib_add_trace (vm, node, b0, sizeof (*t));
1071               t->sw_if_index = sw_if_index0;
1072               t->next_index = next0;
1073               t->is_slow_path = 0;
1074
1075               if (s0)
1076                 t->session_index = s0 - tsm->sessions;
1077               else
1078                 t->session_index = ~0;
1079             }
1080
1081           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
1082           /* verify speculative enqueue, maybe switch current next frame */
1083           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1084                                            to_next, n_left_to_next,
1085                                            bi0, next0);
1086         }
1087
1088       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1089     }
1090
1091   vlib_node_increment_counter (vm, stats_node_index,
1092                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1093                                pkts_processed);
1094   vlib_node_increment_counter (vm, stats_node_index,
1095                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1096   vlib_node_increment_counter (vm, stats_node_index,
1097                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1098   vlib_node_increment_counter (vm, stats_node_index,
1099                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1100                                icmp_packets);
1101   vlib_node_increment_counter (vm, stats_node_index,
1102                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1103                                other_packets);
1104   return frame->n_vectors;
1105 }
1106
1107 static inline uword
1108 nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
1109                                           vlib_node_runtime_t * node,
1110                                           vlib_frame_t * frame,
1111                                           int is_output_feature)
1112 {
1113   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
1114   nat_next_t next_index;
1115   snat_main_t *sm = &snat_main;
1116   f64 now = vlib_time_now (vm);
1117   u32 thread_index = vm->thread_index;
1118   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
1119   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets = 0;
1120
1121   stats_node_index = sm->ed_in2out_slowpath_node_index;
1122
1123   from = vlib_frame_vector_args (frame);
1124   n_left_from = frame->n_vectors;
1125   next_index = node->cached_next_index;
1126
1127   while (n_left_from > 0)
1128     {
1129       u32 n_left_to_next;
1130
1131       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1132
1133       while (n_left_from > 0 && n_left_to_next > 0)
1134         {
1135           u32 bi0;
1136           vlib_buffer_t *b0;
1137           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
1138             new_addr0, old_addr0;
1139           u16 old_port0, new_port0;
1140           ip4_header_t *ip0;
1141           udp_header_t *udp0;
1142           tcp_header_t *tcp0;
1143           icmp46_header_t *icmp0;
1144           snat_session_t *s0 = 0;
1145           clib_bihash_kv_16_8_t kv0, value0;
1146           ip_csum_t sum0;
1147
1148           /* speculatively enqueue b0 to the current next frame */
1149           bi0 = from[0];
1150           to_next[0] = bi0;
1151           from += 1;
1152           to_next += 1;
1153           n_left_from -= 1;
1154           n_left_to_next -= 1;
1155
1156           b0 = vlib_get_buffer (vm, bi0);
1157
1158           if (is_output_feature)
1159             iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1160
1161           next0 = nat_buffer_opaque (b0)->arc_next;
1162
1163           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1164                                   iph_offset0);
1165
1166           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1167           rx_fib_index0 =
1168             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1169                                                  sw_if_index0);
1170
1171           if (PREDICT_FALSE (ip0->ttl == 1))
1172             {
1173               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1174               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1175                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1176                                            0);
1177               next0 = NAT_NEXT_ICMP_ERROR;
1178               goto trace0;
1179             }
1180
1181           udp0 = ip4_next_header (ip0);
1182           tcp0 = (tcp_header_t *) udp0;
1183           icmp0 = (icmp46_header_t *) udp0;
1184           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1185
1186           if (PREDICT_FALSE (proto0 == ~0))
1187             {
1188               s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1189                                                   rx_fib_index0,
1190                                                   thread_index, now,
1191                                                   vm, node);
1192               if (!s0)
1193                 next0 = NAT_NEXT_DROP;
1194
1195               other_packets++;
1196               goto trace0;
1197             }
1198
1199           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1200             {
1201               next0 = icmp_in2out_ed_slow_path
1202                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
1203                  node, next0, now, thread_index, &s0);
1204               icmp_packets++;
1205               goto trace0;
1206             }
1207
1208           // move down
1209           make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
1210                       ip0->protocol, rx_fib_index0,
1211                       vnet_buffer (b0)->ip.reass.l4_src_port,
1212                       vnet_buffer (b0)->ip.reass.l4_dst_port);
1213
1214           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1215             {
1216
1217               if (is_output_feature)
1218                 {
1219                   if (PREDICT_FALSE
1220                       (nat44_ed_not_translate_output_feature
1221                        (sm, ip0, ip0->protocol,
1222                         vnet_buffer (b0)->ip.reass.l4_src_port,
1223                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1224                         thread_index, sw_if_index0,
1225                         vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1226                     goto trace0;
1227
1228                   /*
1229                    * Send DHCP packets to the ipv4 stack, or we won't
1230                    * be able to use dhcp client on the outside interface
1231                    */
1232                   if (PREDICT_FALSE
1233                       (proto0 == SNAT_PROTOCOL_UDP
1234                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1235                            clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
1236                        && ip0->dst_address.as_u32 == 0xffffffff))
1237                     goto trace0;
1238                 }
1239               else
1240                 {
1241                   if (PREDICT_FALSE
1242                       (nat44_ed_not_translate
1243                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1244                         thread_index)))
1245                     goto trace0;
1246                 }
1247
1248               next0 = slow_path_ed (sm, b0, rx_fib_index0, &kv0, &s0, node,
1249                                     next0, thread_index, now);
1250
1251               if (PREDICT_FALSE (next0 == NAT_NEXT_DROP))
1252                 goto trace0;
1253
1254               if (PREDICT_FALSE (!s0))
1255                 goto trace0;
1256
1257             }
1258           else
1259             {
1260               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1261             }
1262
1263
1264           b0->flags |= VNET_BUFFER_F_IS_NATED;
1265
1266           if (!is_output_feature)
1267             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1268
1269           old_addr0 = ip0->src_address.as_u32;
1270           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1271           sum0 = ip0->checksum;
1272           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1273                                  src_address);
1274           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1275             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1276                                    s0->ext_host_addr.as_u32, ip4_header_t,
1277                                    dst_address);
1278           ip0->checksum = ip_csum_fold (sum0);
1279
1280           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1281
1282           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1283             {
1284               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1285                 {
1286                   new_port0 = udp0->src_port = s0->out2in.port;
1287                   sum0 = tcp0->checksum;
1288                   sum0 =
1289                     ip_csum_update (sum0, old_addr0, new_addr0,
1290                                     ip4_header_t, dst_address);
1291                   sum0 =
1292                     ip_csum_update (sum0, old_port0, new_port0,
1293                                     ip4_header_t, length);
1294                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1295                     {
1296                       sum0 =
1297                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1298                                         s0->ext_host_addr.as_u32,
1299                                         ip4_header_t, dst_address);
1300                       sum0 =
1301                         ip_csum_update (sum0,
1302                                         vnet_buffer (b0)->ip.
1303                                         reass.l4_dst_port, s0->ext_host_port,
1304                                         ip4_header_t, length);
1305                       tcp0->dst_port = s0->ext_host_port;
1306                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1307                     }
1308                   mss_clamping (sm, tcp0, &sum0);
1309                   tcp0->checksum = ip_csum_fold (sum0);
1310                 }
1311               tcp_packets++;
1312               if (nat44_set_tcp_session_state_i2o (sm, s0, b0, thread_index))
1313                 goto trace0;
1314             }
1315           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1316                    && udp0->checksum)
1317             {
1318               new_port0 = udp0->src_port = s0->out2in.port;
1319               sum0 = udp0->checksum;
1320               sum0 =
1321                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1322                                 dst_address);
1323               sum0 =
1324                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1325                                 length);
1326               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1327                 {
1328                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1329                                          s0->ext_host_addr.as_u32,
1330                                          ip4_header_t, dst_address);
1331                   sum0 =
1332                     ip_csum_update (sum0,
1333                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1334                                     s0->ext_host_port, ip4_header_t, length);
1335                   udp0->dst_port = s0->ext_host_port;
1336                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1337                 }
1338               udp0->checksum = ip_csum_fold (sum0);
1339               udp_packets++;
1340             }
1341           else
1342             {
1343               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1344                 {
1345                   new_port0 = udp0->src_port = s0->out2in.port;
1346                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1347                     {
1348                       udp0->dst_port = s0->ext_host_port;
1349                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1350                     }
1351                   udp_packets++;
1352                 }
1353             }
1354
1355           /* Accounting */
1356           nat44_session_update_counters (s0, now,
1357                                          vlib_buffer_length_in_chain
1358                                          (vm, b0), thread_index);
1359           /* Per-user LRU list maintenance */
1360           nat44_session_update_lru (sm, s0, thread_index);
1361
1362         trace0:
1363           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1364                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1365             {
1366               nat_in2out_ed_trace_t *t =
1367                 vlib_add_trace (vm, node, b0, sizeof (*t));
1368               t->sw_if_index = sw_if_index0;
1369               t->next_index = next0;
1370               t->is_slow_path = 1;
1371
1372               if (s0)
1373                 t->session_index = s0 - tsm->sessions;
1374               else
1375                 t->session_index = ~0;
1376             }
1377
1378           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
1379
1380           /* verify speculative enqueue, maybe switch current next frame */
1381           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1382                                            to_next, n_left_to_next,
1383                                            bi0, next0);
1384         }
1385
1386       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1387     }
1388
1389   vlib_node_increment_counter (vm, stats_node_index,
1390                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1391                                pkts_processed);
1392   vlib_node_increment_counter (vm, stats_node_index,
1393                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1394   vlib_node_increment_counter (vm, stats_node_index,
1395                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1396   vlib_node_increment_counter (vm, stats_node_index,
1397                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1398                                icmp_packets);
1399   vlib_node_increment_counter (vm, stats_node_index,
1400                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1401                                other_packets);
1402   return frame->n_vectors;
1403 }
1404
1405 VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
1406                                      vlib_node_runtime_t * node,
1407                                      vlib_frame_t * frame)
1408 {
1409   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
1410 }
1411
1412 /* *INDENT-OFF* */
1413 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1414   .name = "nat44-ed-in2out",
1415   .vector_size = sizeof (u32),
1416   .sibling_of = "nat-default",
1417   .format_trace = format_nat_in2out_ed_trace,
1418   .type = VLIB_NODE_TYPE_INTERNAL,
1419   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1420   .error_strings = nat_in2out_ed_error_strings,
1421   .runtime_data_bytes = sizeof (snat_runtime_t),
1422 };
1423 /* *INDENT-ON* */
1424
1425 VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
1426                                             vlib_node_runtime_t * node,
1427                                             vlib_frame_t * frame)
1428 {
1429   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
1430 }
1431
1432 /* *INDENT-OFF* */
1433 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1434   .name = "nat44-ed-in2out-output",
1435   .vector_size = sizeof (u32),
1436   .sibling_of = "nat-default",
1437   .format_trace = format_nat_in2out_ed_trace,
1438   .type = VLIB_NODE_TYPE_INTERNAL,
1439   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1440   .error_strings = nat_in2out_ed_error_strings,
1441   .runtime_data_bytes = sizeof (snat_runtime_t),
1442 };
1443 /* *INDENT-ON* */
1444
1445 VLIB_NODE_FN (nat44_ed_in2out_slowpath_node) (vlib_main_t * vm,
1446                                               vlib_node_runtime_t *
1447                                               node, vlib_frame_t * frame)
1448 {
1449   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 0);
1450 }
1451
1452 /* *INDENT-OFF* */
1453 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1454   .name = "nat44-ed-in2out-slowpath",
1455   .vector_size = sizeof (u32),
1456   .sibling_of = "nat-default",
1457   .format_trace = format_nat_in2out_ed_trace,
1458   .type = VLIB_NODE_TYPE_INTERNAL,
1459   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1460   .error_strings = nat_in2out_ed_error_strings,
1461   .runtime_data_bytes = sizeof (snat_runtime_t),
1462 };
1463 /* *INDENT-ON* */
1464
1465 VLIB_NODE_FN (nat44_ed_in2out_output_slowpath_node) (vlib_main_t * vm,
1466                                                      vlib_node_runtime_t
1467                                                      * node,
1468                                                      vlib_frame_t * frame)
1469 {
1470   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 1);
1471 }
1472
1473 /* *INDENT-OFF* */
1474 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1475   .name = "nat44-ed-in2out-output-slowpath",
1476   .vector_size = sizeof (u32),
1477   .sibling_of = "nat-default",
1478   .format_trace = format_nat_in2out_ed_trace,
1479   .type = VLIB_NODE_TYPE_INTERNAL,
1480   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1481   .error_strings = nat_in2out_ed_error_strings,
1482   .runtime_data_bytes = sizeof (snat_runtime_t),
1483 };
1484 /* *INDENT-ON* */
1485
1486 static u8 *
1487 format_nat_pre_trace (u8 * s, va_list * args)
1488 {
1489   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1490   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1491   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1492   return format (s, "in2out next_index %d", t->next_index);
1493 }
1494
1495 VLIB_NODE_FN (nat_pre_in2out_node)
1496   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1497 {
1498   return nat_pre_node_fn_inline (vm, node, frame,
1499                                  NAT_NEXT_IN2OUT_ED_FAST_PATH);
1500 }
1501
1502 /* *INDENT-OFF* */
1503 VLIB_REGISTER_NODE (nat_pre_in2out_node) = {
1504   .name = "nat-pre-in2out",
1505   .vector_size = sizeof (u32),
1506   .sibling_of = "nat-default",
1507   .format_trace = format_nat_pre_trace,
1508   .type = VLIB_NODE_TYPE_INTERNAL,
1509   .n_errors = 0,
1510 };
1511 /* *INDENT-ON* */
1512
1513 /*
1514  * fd.io coding-style-patch-verification: ON
1515  *
1516  * Local Variables:
1517  * eval: (c-set-style "gnu")
1518  * End:
1519  */