src/plugins/nat/out2in.c

   1 /*
   2  * Copyright (c) 2016 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
  24 #include <vnet/ip/ip.h>
  25 #include <vnet/udp/udp.h>
  26 #include <vnet/ethernet/ethernet.h>
  27 #include <vnet/fib/ip4_fib.h>
  28 #include <nat/nat.h>
  29 #include <nat/nat_ipfix_logging.h>
  30 #include <nat/nat_reass.h>
  31 #include <nat/nat_inlines.h>
  32 #include <nat/nat_syslog.h>
  33
  34 #include <vppinfra/hash.h>
  35 #include <vppinfra/error.h>
  36 #include <vppinfra/elog.h>
  37
  38 typedef struct
  39 {
  40   u32 sw_if_index;
  41   u32 next_index;
  42   u32 session_index;
  43 } snat_out2in_trace_t;
  44
  45 /* packet trace format function */
  46 static u8 *
  47 format_snat_out2in_trace (u8 * s, va_list * args)
  48 {
  49   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  50   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  51   snat_out2in_trace_t *t = va_arg (*args, snat_out2in_trace_t *);
  52
  53   s =
  54     format (s,
  55             "NAT44_OUT2IN: sw_if_index %d, next index %d, session index %d",
  56             t->sw_if_index, t->next_index, t->session_index);
  57   return s;
  58 }
  59
  60 static u8 *
  61 format_snat_out2in_fast_trace (u8 * s, va_list * args)
  62 {
  63   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  64   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  65   snat_out2in_trace_t *t = va_arg (*args, snat_out2in_trace_t *);
  66
  67   s = format (s, "NAT44_OUT2IN_FAST: sw_if_index %d, next index %d",
  68               t->sw_if_index, t->next_index);
  69   return s;
  70 }
  71
  72 vlib_node_registration_t snat_out2in_node;
  73 vlib_node_registration_t snat_out2in_fast_node;
  74 vlib_node_registration_t nat44_out2in_reass_node;
  75
  76 #define foreach_snat_out2in_error                       \
  77 _(UNSUPPORTED_PROTOCOL, "Unsupported protocol")         \
  78 _(OUT2IN_PACKETS, "Good out2in packets processed")      \
  79 _(OUT_OF_PORTS, "Out of ports")                         \
  80 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  81 _(NO_TRANSLATION, "No translation")                     \
  82 _(MAX_SESSIONS_EXCEEDED, "Maximum sessions exceeded")   \
  83 _(DROP_FRAGMENT, "Drop fragment")                       \
  84 _(MAX_REASS, "Maximum reassemblies exceeded")           \
  85 _(MAX_FRAG, "Maximum fragments per reassembly exceeded")
  86
  87 typedef enum
  88 {
  89 #define _(sym,str) SNAT_OUT2IN_ERROR_##sym,
  90   foreach_snat_out2in_error
  91 #undef _
  92     SNAT_OUT2IN_N_ERROR,
  93 } snat_out2in_error_t;
  94
  95 static char *snat_out2in_error_strings[] = {
  96 #define _(sym,string) string,
  97   foreach_snat_out2in_error
  98 #undef _
  99 };
 100
 101 typedef enum
 102 {
 103   SNAT_OUT2IN_NEXT_DROP,
 104   SNAT_OUT2IN_NEXT_LOOKUP,
 105   SNAT_OUT2IN_NEXT_ICMP_ERROR,
 106   SNAT_OUT2IN_NEXT_REASS,
 107   SNAT_OUT2IN_N_NEXT,
 108 } snat_out2in_next_t;
 109
 110 int
 111 nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
 112 {
 113   snat_main_t *sm = &snat_main;
 114   nat44_is_idle_session_ctx_t *ctx = arg;
 115   snat_session_t *s;
 116   u64 sess_timeout_time;
 117   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 118                                                        ctx->thread_index);
 119   clib_bihash_kv_8_8_t s_kv;
 120
 121   s = pool_elt_at_index (tsm->sessions, kv->value);
 122   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 123   if (ctx->now >= sess_timeout_time)
 124     {
 125       s_kv.key = s->in2out.as_u64;
 126       if (clib_bihash_add_del_8_8 (&tsm->in2out, &s_kv, 0))
 127         nat_log_warn ("out2in key del failed");
 128
 129       snat_ipfix_logging_nat44_ses_delete (s->in2out.addr.as_u32,
 130                                            s->out2in.addr.as_u32,
 131                                            s->in2out.protocol,
 132                                            s->in2out.port,
 133                                            s->out2in.port,
 134                                            s->in2out.fib_index);
 135
 136       nat_syslog_nat44_apmdel (s->user_index, s->in2out.fib_index,
 137                                &s->in2out.addr, s->in2out.port,
 138                                &s->out2in.addr, s->out2in.port,
 139                                s->in2out.protocol);
 140
 141       if (!snat_is_session_static (s))
 142         snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 143                                             &s->out2in);
 144
 145       nat44_delete_session (sm, s, ctx->thread_index);
 146       return 1;
 147     }
 148
 149   return 0;
 150 }
 151
 152 /**
 153  * @brief Create session for static mapping.
 154  *
 155  * Create NAT session initiated by host from external network with static
 156  * mapping.
 157  *
 158  * @param sm     NAT main.
 159  * @param b0     Vlib buffer.
 160  * @param in2out In2out NAT44 session key.
 161  * @param out2in Out2in NAT44 session key.
 162  * @param node   Vlib node.
 163  *
 164  * @returns SNAT session if successfully created otherwise 0.
 165  */
 166 static inline snat_session_t *
 167 create_session_for_static_mapping (snat_main_t * sm,
 168                                    vlib_buffer_t * b0,
 169                                    snat_session_key_t in2out,
 170                                    snat_session_key_t out2in,
 171                                    vlib_node_runtime_t * node,
 172                                    u32 thread_index, f64 now)
 173 {
 174   snat_user_t *u;
 175   snat_session_t *s;
 176   clib_bihash_kv_8_8_t kv0;
 177   ip4_header_t *ip0;
 178   udp_header_t *udp0;
 179   nat44_is_idle_session_ctx_t ctx0;
 180
 181   if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 182     {
 183       b0->error = node->errors[SNAT_OUT2IN_ERROR_MAX_SESSIONS_EXCEEDED];
 184       nat_log_notice ("maximum sessions exceeded");
 185       return 0;
 186     }
 187
 188   ip0 = vlib_buffer_get_current (b0);
 189   udp0 = ip4_next_header (ip0);
 190
 191   u =
 192     nat_user_get_or_create (sm, &in2out.addr, in2out.fib_index, thread_index);
 193   if (!u)
 194     {
 195       nat_log_warn ("create NAT user failed");
 196       return 0;
 197     }
 198
 199   s = nat_session_alloc_or_recycle (sm, u, thread_index);
 200   if (!s)
 201     {
 202       nat44_delete_user_with_no_session (sm, u, thread_index);
 203       nat_log_warn ("create NAT session failed");
 204       return 0;
 205     }
 206
 207   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 208   s->ext_host_addr.as_u32 = ip0->src_address.as_u32;
 209   s->ext_host_port = udp0->src_port;
 210   user_session_increment (sm, u, 1 /* static */ );
 211   s->in2out = in2out;
 212   s->out2in = out2in;
 213   s->in2out.protocol = out2in.protocol;
 214
 215   /* Add to translation hashes */
 216   ctx0.now = now;
 217   ctx0.thread_index = thread_index;
 218   kv0.key = s->in2out.as_u64;
 219   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 220   if (clib_bihash_add_or_overwrite_stale_8_8
 221       (&sm->per_thread_data[thread_index].in2out, &kv0,
 222        nat44_i2o_is_idle_session_cb, &ctx0))
 223     nat_log_notice ("in2out key add failed");
 224
 225   kv0.key = s->out2in.as_u64;
 226
 227   if (clib_bihash_add_or_overwrite_stale_8_8
 228       (&sm->per_thread_data[thread_index].out2in, &kv0,
 229        nat44_o2i_is_idle_session_cb, &ctx0))
 230     nat_log_notice ("out2in key add failed");
 231
 232   /* log NAT event */
 233   snat_ipfix_logging_nat44_ses_create (s->in2out.addr.as_u32,
 234                                        s->out2in.addr.as_u32,
 235                                        s->in2out.protocol,
 236                                        s->in2out.port,
 237                                        s->out2in.port, s->in2out.fib_index);
 238
 239   nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
 240                            &s->in2out.addr, s->in2out.port, &s->out2in.addr,
 241                            s->out2in.port, s->in2out.protocol);
 242
 243   return s;
 244 }
 245
 246 static_always_inline
 247   snat_out2in_error_t icmp_get_key (ip4_header_t * ip0,
 248                                     snat_session_key_t * p_key0)
 249 {
 250   icmp46_header_t *icmp0;
 251   snat_session_key_t key0;
 252   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 253   ip4_header_t *inner_ip0;
 254   void *l4_header = 0;
 255   icmp46_header_t *inner_icmp0;
 256
 257   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 258   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 259
 260   if (!icmp_is_error_message (icmp0))
 261     {
 262       key0.protocol = SNAT_PROTOCOL_ICMP;
 263       key0.addr = ip0->dst_address;
 264       key0.port = echo0->identifier;
 265     }
 266   else
 267     {
 268       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 269       l4_header = ip4_next_header (inner_ip0);
 270       key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
 271       key0.addr = inner_ip0->src_address;
 272       switch (key0.protocol)
 273         {
 274         case SNAT_PROTOCOL_ICMP:
 275           inner_icmp0 = (icmp46_header_t *) l4_header;
 276           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 277           key0.port = inner_echo0->identifier;
 278           break;
 279         case SNAT_PROTOCOL_UDP:
 280         case SNAT_PROTOCOL_TCP:
 281           key0.port = ((tcp_udp_header_t *) l4_header)->src_port;
 282           break;
 283         default:
 284           return SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL;
 285         }
 286     }
 287   *p_key0 = key0;
 288   return -1;                    /* success */
 289 }
 290
 291 /**
 292  * Get address and port values to be used for ICMP packet translation
 293  * and create session if needed
 294  *
 295  * @param[in,out] sm             NAT main
 296  * @param[in,out] node           NAT node runtime
 297  * @param[in] thread_index       thread index
 298  * @param[in,out] b0             buffer containing packet to be translated
 299  * @param[out] p_proto           protocol used for matching
 300  * @param[out] p_value           address and port after NAT translation
 301  * @param[out] p_dont_translate  if packet should not be translated
 302  * @param d                      optional parameter
 303  * @param e                      optional parameter
 304  */
 305 u32
 306 icmp_match_out2in_slow (snat_main_t * sm, vlib_node_runtime_t * node,
 307                         u32 thread_index, vlib_buffer_t * b0,
 308                         ip4_header_t * ip0, u8 * p_proto,
 309                         snat_session_key_t * p_value,
 310                         u8 * p_dont_translate, void *d, void *e)
 311 {
 312   icmp46_header_t *icmp0;
 313   u32 sw_if_index0;
 314   u32 rx_fib_index0;
 315   snat_session_key_t key0;
 316   snat_session_key_t sm0;
 317   snat_session_t *s0 = 0;
 318   u8 dont_translate = 0;
 319   clib_bihash_kv_8_8_t kv0, value0;
 320   u8 is_addr_only;
 321   u32 next0 = ~0;
 322   int err;
 323   u8 identity_nat;
 324
 325   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 326   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 327   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 328
 329   key0.protocol = 0;
 330
 331   err = icmp_get_key (ip0, &key0);
 332   if (err != -1)
 333     {
 334       b0->error = node->errors[SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL];
 335       next0 = SNAT_OUT2IN_NEXT_DROP;
 336       goto out;
 337     }
 338   key0.fib_index = rx_fib_index0;
 339
 340   kv0.key = key0.as_u64;
 341
 342   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
 343                               &value0))
 344     {
 345       /* Try to match static mapping by external address and port,
 346          destination address and port in packet */
 347       if (snat_static_mapping_match
 348           (sm, key0, &sm0, 1, &is_addr_only, 0, 0, 0, &identity_nat))
 349         {
 350           if (!sm->forwarding_enabled)
 351             {
 352               /* Don't NAT packet aimed at the intfc address */
 353               if (PREDICT_FALSE (is_interface_addr (sm, node, sw_if_index0,
 354                                                     ip0->dst_address.as_u32)))
 355                 {
 356                   dont_translate = 1;
 357                   goto out;
 358                 }
 359               b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
 360               next0 = SNAT_OUT2IN_NEXT_DROP;
 361               goto out;
 362             }
 363           else
 364             {
 365               dont_translate = 1;
 366               goto out;
 367             }
 368         }
 369
 370       if (PREDICT_FALSE (icmp0->type != ICMP4_echo_reply &&
 371                          (icmp0->type != ICMP4_echo_request
 372                           || !is_addr_only)))
 373         {
 374           b0->error = node->errors[SNAT_OUT2IN_ERROR_BAD_ICMP_TYPE];
 375           next0 = SNAT_OUT2IN_NEXT_DROP;
 376           goto out;
 377         }
 378
 379       if (PREDICT_FALSE (identity_nat))
 380         {
 381           dont_translate = 1;
 382           goto out;
 383         }
 384       /* Create session initiated by host from external network */
 385       s0 = create_session_for_static_mapping (sm, b0, sm0, key0,
 386                                               node, thread_index,
 387                                               vlib_time_now (sm->vlib_main));
 388
 389       if (!s0)
 390         {
 391           next0 = SNAT_OUT2IN_NEXT_DROP;
 392           goto out;
 393         }
 394     }
 395   else
 396     {
 397       if (PREDICT_FALSE (icmp0->type != ICMP4_echo_reply &&
 398                          icmp0->type != ICMP4_echo_request &&
 399                          !icmp_is_error_message (icmp0)))
 400         {
 401           b0->error = node->errors[SNAT_OUT2IN_ERROR_BAD_ICMP_TYPE];
 402           next0 = SNAT_OUT2IN_NEXT_DROP;
 403           goto out;
 404         }
 405
 406       s0 = pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
 407                               value0.value);
 408     }
 409
 410 out:
 411   *p_proto = key0.protocol;
 412   if (s0)
 413     *p_value = s0->in2out;
 414   *p_dont_translate = dont_translate;
 415   if (d)
 416     *(snat_session_t **) d = s0;
 417   return next0;
 418 }
 419
 420 /**
 421  * Get address and port values to be used for ICMP packet translation
 422  *
 423  * @param[in] sm                 NAT main
 424  * @param[in,out] node           NAT node runtime
 425  * @param[in] thread_index       thread index
 426  * @param[in,out] b0             buffer containing packet to be translated
 427  * @param[out] p_proto           protocol used for matching
 428  * @param[out] p_value           address and port after NAT translation
 429  * @param[out] p_dont_translate  if packet should not be translated
 430  * @param d                      optional parameter
 431  * @param e                      optional parameter
 432  */
 433 u32
 434 icmp_match_out2in_fast (snat_main_t * sm, vlib_node_runtime_t * node,
 435                         u32 thread_index, vlib_buffer_t * b0,
 436                         ip4_header_t * ip0, u8 * p_proto,
 437                         snat_session_key_t * p_value,
 438                         u8 * p_dont_translate, void *d, void *e)
 439 {
 440   icmp46_header_t *icmp0;
 441   u32 sw_if_index0;
 442   u32 rx_fib_index0;
 443   snat_session_key_t key0;
 444   snat_session_key_t sm0;
 445   u8 dont_translate = 0;
 446   u8 is_addr_only;
 447   u32 next0 = ~0;
 448   int err;
 449
 450   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 451   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 452   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 453
 454   err = icmp_get_key (ip0, &key0);
 455   if (err != -1)
 456     {
 457       b0->error = node->errors[err];
 458       next0 = SNAT_OUT2IN_NEXT_DROP;
 459       goto out2;
 460     }
 461   key0.fib_index = rx_fib_index0;
 462
 463   if (snat_static_mapping_match
 464       (sm, key0, &sm0, 1, &is_addr_only, 0, 0, 0, 0))
 465     {
 466       /* Don't NAT packet aimed at the intfc address */
 467       if (is_interface_addr (sm, node, sw_if_index0, ip0->dst_address.as_u32))
 468         {
 469           dont_translate = 1;
 470           goto out;
 471         }
 472       b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
 473       next0 = SNAT_OUT2IN_NEXT_DROP;
 474       goto out;
 475     }
 476
 477   if (PREDICT_FALSE (icmp0->type != ICMP4_echo_reply &&
 478                      (icmp0->type != ICMP4_echo_request || !is_addr_only) &&
 479                      !icmp_is_error_message (icmp0)))
 480     {
 481       b0->error = node->errors[SNAT_OUT2IN_ERROR_BAD_ICMP_TYPE];
 482       next0 = SNAT_OUT2IN_NEXT_DROP;
 483       goto out;
 484     }
 485
 486 out:
 487   *p_value = sm0;
 488 out2:
 489   *p_proto = key0.protocol;
 490   *p_dont_translate = dont_translate;
 491   return next0;
 492 }
 493
 494 u32
 495 icmp_out2in (snat_main_t * sm,
 496              vlib_buffer_t * b0,
 497              ip4_header_t * ip0,
 498              icmp46_header_t * icmp0,
 499              u32 sw_if_index0,
 500              u32 rx_fib_index0,
 501              vlib_node_runtime_t * node,
 502              u32 next0, u32 thread_index, void *d, void *e)
 503 {
 504   snat_session_key_t sm0;
 505   u8 protocol;
 506   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 507   ip4_header_t *inner_ip0 = 0;
 508   void *l4_header = 0;
 509   icmp46_header_t *inner_icmp0;
 510   u8 dont_translate;
 511   u32 new_addr0, old_addr0;
 512   u16 old_id0, new_id0;
 513   ip_csum_t sum0;
 514   u16 checksum0;
 515   u32 next0_tmp;
 516
 517   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 518
 519   next0_tmp = sm->icmp_match_out2in_cb (sm, node, thread_index, b0, ip0,
 520                                         &protocol, &sm0, &dont_translate, d,
 521                                         e);
 522   if (next0_tmp != ~0)
 523     next0 = next0_tmp;
 524   if (next0 == SNAT_OUT2IN_NEXT_DROP || dont_translate)
 525     goto out;
 526
 527   if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
 528     {
 529       sum0 = ip_incremental_checksum_buffer (sm->vlib_main, b0, (u8 *) icmp0 -
 530                                              (u8 *)
 531                                              vlib_buffer_get_current (b0),
 532                                              ntohs (ip0->length) -
 533                                              ip4_header_bytes (ip0), 0);
 534       checksum0 = ~ip_csum_fold (sum0);
 535       if (checksum0 != 0 && checksum0 != 0xffff)
 536         {
 537           next0 = SNAT_OUT2IN_NEXT_DROP;
 538           goto out;
 539         }
 540     }
 541
 542   old_addr0 = ip0->dst_address.as_u32;
 543   new_addr0 = ip0->dst_address.as_u32 = sm0.addr.as_u32;
 544   vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
 545
 546   sum0 = ip0->checksum;
 547   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 548                          dst_address /* changed member */ );
 549   ip0->checksum = ip_csum_fold (sum0);
 550
 551   if (icmp0->checksum == 0)
 552     icmp0->checksum = 0xffff;
 553
 554   if (!icmp_is_error_message (icmp0))
 555     {
 556       new_id0 = sm0.port;
 557       if (PREDICT_FALSE (new_id0 != echo0->identifier))
 558         {
 559           old_id0 = echo0->identifier;
 560           new_id0 = sm0.port;
 561           echo0->identifier = new_id0;
 562
 563           sum0 = icmp0->checksum;
 564           sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 565                                  identifier /* changed member */ );
 566           icmp0->checksum = ip_csum_fold (sum0);
 567         }
 568     }
 569   else
 570     {
 571       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 572       l4_header = ip4_next_header (inner_ip0);
 573
 574       if (!ip4_header_checksum_is_valid (inner_ip0))
 575         {
 576           next0 = SNAT_OUT2IN_NEXT_DROP;
 577           goto out;
 578         }
 579
 580       old_addr0 = inner_ip0->src_address.as_u32;
 581       inner_ip0->src_address = sm0.addr;
 582       new_addr0 = inner_ip0->src_address.as_u32;
 583
 584       sum0 = icmp0->checksum;
 585       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 586                              src_address /* changed member */ );
 587       icmp0->checksum = ip_csum_fold (sum0);
 588
 589       switch (protocol)
 590         {
 591         case SNAT_PROTOCOL_ICMP:
 592           inner_icmp0 = (icmp46_header_t *) l4_header;
 593           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 594
 595           old_id0 = inner_echo0->identifier;
 596           new_id0 = sm0.port;
 597           inner_echo0->identifier = new_id0;
 598
 599           sum0 = icmp0->checksum;
 600           sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 601                                  identifier);
 602           icmp0->checksum = ip_csum_fold (sum0);
 603           break;
 604         case SNAT_PROTOCOL_UDP:
 605         case SNAT_PROTOCOL_TCP:
 606           old_id0 = ((tcp_udp_header_t *) l4_header)->src_port;
 607           new_id0 = sm0.port;
 608           ((tcp_udp_header_t *) l4_header)->src_port = new_id0;
 609
 610           sum0 = icmp0->checksum;
 611           sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
 612                                  src_port);
 613           icmp0->checksum = ip_csum_fold (sum0);
 614           break;
 615         default:
 616           ASSERT (0);
 617         }
 618     }
 619
 620 out:
 621   return next0;
 622 }
 623
 624
 625 static inline u32
 626 icmp_out2in_slow_path (snat_main_t * sm,
 627                        vlib_buffer_t * b0,
 628                        ip4_header_t * ip0,
 629                        icmp46_header_t * icmp0,
 630                        u32 sw_if_index0,
 631                        u32 rx_fib_index0,
 632                        vlib_node_runtime_t * node,
 633                        u32 next0, f64 now,
 634                        u32 thread_index, snat_session_t ** p_s0)
 635 {
 636   next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 637                        next0, thread_index, p_s0, 0);
 638   snat_session_t *s0 = *p_s0;
 639   if (PREDICT_TRUE (next0 != SNAT_OUT2IN_NEXT_DROP && s0))
 640     {
 641       /* Accounting */
 642       nat44_session_update_counters (s0, now,
 643                                      vlib_buffer_length_in_chain
 644                                      (sm->vlib_main, b0));
 645       /* Per-user LRU list maintenance */
 646       nat44_session_update_lru (sm, s0, thread_index);
 647     }
 648   return next0;
 649 }
 650
 651 static int
 652 nat_out2in_sm_unknown_proto (snat_main_t * sm,
 653                              vlib_buffer_t * b,
 654                              ip4_header_t * ip, u32 rx_fib_index)
 655 {
 656   clib_bihash_kv_8_8_t kv, value;
 657   snat_static_mapping_t *m;
 658   snat_session_key_t m_key;
 659   u32 old_addr, new_addr;
 660   ip_csum_t sum;
 661
 662   m_key.addr = ip->dst_address;
 663   m_key.port = 0;
 664   m_key.protocol = 0;
 665   m_key.fib_index = 0;
 666   kv.key = m_key.as_u64;
 667   if (clib_bihash_search_8_8 (&sm->static_mapping_by_external, &kv, &value))
 668     return 1;
 669
 670   m = pool_elt_at_index (sm->static_mappings, value.value);
 671
 672   old_addr = ip->dst_address.as_u32;
 673   new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 674   sum = ip->checksum;
 675   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 676   ip->checksum = ip_csum_fold (sum);
 677
 678   vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 679   return 0;
 680 }
 681
 682 static uword
 683 snat_out2in_node_fn (vlib_main_t * vm,
 684                      vlib_node_runtime_t * node, vlib_frame_t * frame)
 685 {
 686   u32 n_left_from, *from, *to_next;
 687   snat_out2in_next_t next_index;
 688   u32 pkts_processed = 0;
 689   snat_main_t *sm = &snat_main;
 690   f64 now = vlib_time_now (vm);
 691   u32 thread_index = vm->thread_index;
 692
 693   from = vlib_frame_vector_args (frame);
 694   n_left_from = frame->n_vectors;
 695   next_index = node->cached_next_index;
 696
 697   while (n_left_from > 0)
 698     {
 699       u32 n_left_to_next;
 700
 701       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 702
 703       while (n_left_from >= 4 && n_left_to_next >= 2)
 704         {
 705           u32 bi0, bi1;
 706           vlib_buffer_t *b0, *b1;
 707           u32 next0 = SNAT_OUT2IN_NEXT_LOOKUP;
 708           u32 next1 = SNAT_OUT2IN_NEXT_LOOKUP;
 709           u32 sw_if_index0, sw_if_index1;
 710           ip4_header_t *ip0, *ip1;
 711           ip_csum_t sum0, sum1;
 712           u32 new_addr0, old_addr0;
 713           u16 new_port0, old_port0;
 714           u32 new_addr1, old_addr1;
 715           u16 new_port1, old_port1;
 716           udp_header_t *udp0, *udp1;
 717           tcp_header_t *tcp0, *tcp1;
 718           icmp46_header_t *icmp0, *icmp1;
 719           snat_session_key_t key0, key1, sm0, sm1;
 720           u32 rx_fib_index0, rx_fib_index1;
 721           u32 proto0, proto1;
 722           snat_session_t *s0 = 0, *s1 = 0;
 723           clib_bihash_kv_8_8_t kv0, kv1, value0, value1;
 724           u8 identity_nat0, identity_nat1;
 725
 726           /* Prefetch next iteration. */
 727           {
 728             vlib_buffer_t *p2, *p3;
 729
 730             p2 = vlib_get_buffer (vm, from[2]);
 731             p3 = vlib_get_buffer (vm, from[3]);
 732
 733             vlib_prefetch_buffer_header (p2, LOAD);
 734             vlib_prefetch_buffer_header (p3, LOAD);
 735
 736             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 737             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 738           }
 739
 740           /* speculatively enqueue b0 and b1 to the current next frame */
 741           to_next[0] = bi0 = from[0];
 742           to_next[1] = bi1 = from[1];
 743           from += 2;
 744           to_next += 2;
 745           n_left_from -= 2;
 746           n_left_to_next -= 2;
 747
 748           b0 = vlib_get_buffer (vm, bi0);
 749           b1 = vlib_get_buffer (vm, bi1);
 750
 751           vnet_buffer (b0)->snat.flags = 0;
 752           vnet_buffer (b1)->snat.flags = 0;
 753
 754           ip0 = vlib_buffer_get_current (b0);
 755           udp0 = ip4_next_header (ip0);
 756           tcp0 = (tcp_header_t *) udp0;
 757           icmp0 = (icmp46_header_t *) udp0;
 758
 759           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 760           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 761                                    sw_if_index0);
 762
 763           if (PREDICT_FALSE (ip0->ttl == 1))
 764             {
 765               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 766               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 767                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 768                                            0);
 769               next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR;
 770               goto trace0;
 771             }
 772
 773           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 774
 775           if (PREDICT_FALSE (proto0 == ~0))
 776             {
 777               if (nat_out2in_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 778                 {
 779                   if (!sm->forwarding_enabled)
 780                     {
 781                       b0->error =
 782                         node->errors[SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL];
 783                       next0 = SNAT_OUT2IN_NEXT_DROP;
 784                     }
 785                 }
 786               goto trace0;
 787             }
 788
 789           if (PREDICT_FALSE (ip4_is_fragment (ip0)))
 790             {
 791               next0 = SNAT_OUT2IN_NEXT_REASS;
 792               goto trace0;
 793             }
 794
 795           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 796             {
 797               next0 = icmp_out2in_slow_path
 798                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 799                  next0, now, thread_index, &s0);
 800               goto trace0;
 801             }
 802
 803           key0.addr = ip0->dst_address;
 804           key0.port = udp0->dst_port;
 805           key0.protocol = proto0;
 806           key0.fib_index = rx_fib_index0;
 807
 808           kv0.key = key0.as_u64;
 809
 810           if (clib_bihash_search_8_8
 811               (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
 812             {
 813               /* Try to match static mapping by external address and port,
 814                  destination address and port in packet */
 815               if (snat_static_mapping_match
 816                   (sm, key0, &sm0, 1, 0, 0, 0, 0, &identity_nat0))
 817                 {
 818                   /*
 819                    * Send DHCP packets to the ipv4 stack, or we won't
 820                    * be able to use dhcp client on the outside interface
 821                    */
 822                   if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
 823                                      && (udp0->dst_port ==
 824                                          clib_host_to_net_u16
 825                                          (UDP_DST_PORT_dhcp_to_client))))
 826                     {
 827                       vnet_feature_next (&next0, b0);
 828                       goto trace0;
 829                     }
 830
 831                   if (!sm->forwarding_enabled)
 832                     {
 833                       b0->error =
 834                         node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
 835                       next0 = SNAT_OUT2IN_NEXT_DROP;
 836                     }
 837                   goto trace0;
 838                 }
 839
 840               if (PREDICT_FALSE (identity_nat0))
 841                 goto trace0;
 842
 843               /* Create session initiated by host from external network */
 844               s0 = create_session_for_static_mapping (sm, b0, sm0, key0, node,
 845                                                       thread_index, now);
 846               if (!s0)
 847                 {
 848                   next0 = SNAT_OUT2IN_NEXT_DROP;
 849                   goto trace0;
 850                 }
 851             }
 852           else
 853             s0 =
 854               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
 855                                  value0.value);
 856
 857           old_addr0 = ip0->dst_address.as_u32;
 858           ip0->dst_address = s0->in2out.addr;
 859           new_addr0 = ip0->dst_address.as_u32;
 860           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 861
 862           sum0 = ip0->checksum;
 863           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
 864                                  ip4_header_t,
 865                                  dst_address /* changed member */ );
 866           ip0->checksum = ip_csum_fold (sum0);
 867
 868           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
 869             {
 870               old_port0 = tcp0->dst_port;
 871               tcp0->dst_port = s0->in2out.port;
 872               new_port0 = tcp0->dst_port;
 873
 874               sum0 = tcp0->checksum;
 875               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
 876                                      ip4_header_t,
 877                                      dst_address /* changed member */ );
 878
 879               sum0 = ip_csum_update (sum0, old_port0, new_port0,
 880                                      ip4_header_t /* cheat */ ,
 881                                      length /* changed member */ );
 882               tcp0->checksum = ip_csum_fold (sum0);
 883             }
 884           else
 885             {
 886               old_port0 = udp0->dst_port;
 887               udp0->dst_port = s0->in2out.port;
 888               udp0->checksum = 0;
 889             }
 890
 891           /* Accounting */
 892           nat44_session_update_counters (s0, now,
 893                                          vlib_buffer_length_in_chain (vm,
 894                                                                       b0));
 895           /* Per-user LRU list maintenance */
 896           nat44_session_update_lru (sm, s0, thread_index);
 897         trace0:
 898
 899           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 900                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 901             {
 902               snat_out2in_trace_t *t =
 903                 vlib_add_trace (vm, node, b0, sizeof (*t));
 904               t->sw_if_index = sw_if_index0;
 905               t->next_index = next0;
 906               t->session_index = ~0;
 907               if (s0)
 908                 t->session_index =
 909                   s0 - sm->per_thread_data[thread_index].sessions;
 910             }
 911
 912           pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;
 913
 914
 915           ip1 = vlib_buffer_get_current (b1);
 916           udp1 = ip4_next_header (ip1);
 917           tcp1 = (tcp_header_t *) udp1;
 918           icmp1 = (icmp46_header_t *) udp1;
 919
 920           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
 921           rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 922                                    sw_if_index1);
 923
 924           if (PREDICT_FALSE (ip1->ttl == 1))
 925             {
 926               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 927               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
 928                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 929                                            0);
 930               next1 = SNAT_OUT2IN_NEXT_ICMP_ERROR;
 931               goto trace1;
 932             }
 933
 934           proto1 = ip_proto_to_snat_proto (ip1->protocol);
 935
 936           if (PREDICT_FALSE (proto1 == ~0))
 937             {
 938               if (nat_out2in_sm_unknown_proto (sm, b1, ip1, rx_fib_index1))
 939                 {
 940                   if (!sm->forwarding_enabled)
 941                     {
 942                       b1->error =
 943                         node->errors[SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL];
 944                       next1 = SNAT_OUT2IN_NEXT_DROP;
 945                     }
 946                 }
 947               goto trace1;
 948             }
 949
 950           if (PREDICT_FALSE (ip4_is_fragment (ip1)))
 951             {
 952               next1 = SNAT_OUT2IN_NEXT_REASS;
 953               goto trace1;
 954             }
 955
 956           if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
 957             {
 958               next1 = icmp_out2in_slow_path
 959                 (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
 960                  next1, now, thread_index, &s1);
 961               goto trace1;
 962             }
 963
 964           key1.addr = ip1->dst_address;
 965           key1.port = udp1->dst_port;
 966           key1.protocol = proto1;
 967           key1.fib_index = rx_fib_index1;
 968
 969           kv1.key = key1.as_u64;
 970
 971           if (clib_bihash_search_8_8
 972               (&sm->per_thread_data[thread_index].out2in, &kv1, &value1))
 973             {
 974               /* Try to match static mapping by external address and port,
 975                  destination address and port in packet */
 976               if (snat_static_mapping_match
 977                   (sm, key1, &sm1, 1, 0, 0, 0, 0, &identity_nat1))
 978                 {
 979                   /*
 980                    * Send DHCP packets to the ipv4 stack, or we won't
 981                    * be able to use dhcp client on the outside interface
 982                    */
 983                   if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_UDP
 984                                      && (udp1->dst_port ==
 985                                          clib_host_to_net_u16
 986                                          (UDP_DST_PORT_dhcp_to_client))))
 987                     {
 988                       vnet_feature_next (&next1, b1);
 989                       goto trace1;
 990                     }
 991
 992                   if (!sm->forwarding_enabled)
 993                     {
 994                       b1->error =
 995                         node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
 996                       next1 = SNAT_OUT2IN_NEXT_DROP;
 997                     }
 998                   goto trace1;
 999                 }
1000
1001               if (PREDICT_FALSE (identity_nat1))
1002                 goto trace1;
1003
1004               /* Create session initiated by host from external network */
1005               s1 = create_session_for_static_mapping (sm, b1, sm1, key1, node,
1006                                                       thread_index, now);
1007               if (!s1)
1008                 {
1009                   next1 = SNAT_OUT2IN_NEXT_DROP;
1010                   goto trace1;
1011                 }
1012             }
1013           else
1014             s1 =
1015               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1016                                  value1.value);
1017
1018           old_addr1 = ip1->dst_address.as_u32;
1019           ip1->dst_address = s1->in2out.addr;
1020           new_addr1 = ip1->dst_address.as_u32;
1021           vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->in2out.fib_index;
1022
1023           sum1 = ip1->checksum;
1024           sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1025                                  ip4_header_t,
1026                                  dst_address /* changed member */ );
1027           ip1->checksum = ip_csum_fold (sum1);
1028
1029           if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1030             {
1031               old_port1 = tcp1->dst_port;
1032               tcp1->dst_port = s1->in2out.port;
1033               new_port1 = tcp1->dst_port;
1034
1035               sum1 = tcp1->checksum;
1036               sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1037                                      ip4_header_t,
1038                                      dst_address /* changed member */ );
1039
1040               sum1 = ip_csum_update (sum1, old_port1, new_port1,
1041                                      ip4_header_t /* cheat */ ,
1042                                      length /* changed member */ );
1043               tcp1->checksum = ip_csum_fold (sum1);
1044             }
1045           else
1046             {
1047               old_port1 = udp1->dst_port;
1048               udp1->dst_port = s1->in2out.port;
1049               udp1->checksum = 0;
1050             }
1051
1052           /* Accounting */
1053           nat44_session_update_counters (s1, now,
1054                                          vlib_buffer_length_in_chain (vm,
1055                                                                       b1));
1056           /* Per-user LRU list maintenance */
1057           nat44_session_update_lru (sm, s1, thread_index);
1058         trace1:
1059
1060           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1061                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1062             {
1063               snat_out2in_trace_t *t =
1064                 vlib_add_trace (vm, node, b1, sizeof (*t));
1065               t->sw_if_index = sw_if_index1;
1066               t->next_index = next1;
1067               t->session_index = ~0;
1068               if (s1)
1069                 t->session_index =
1070                   s1 - sm->per_thread_data[thread_index].sessions;
1071             }
1072
1073           pkts_processed += next1 != SNAT_OUT2IN_NEXT_DROP;
1074
1075           /* verify speculative enqueues, maybe switch current next frame */
1076           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1077                                            to_next, n_left_to_next,
1078                                            bi0, bi1, next0, next1);
1079         }
1080
1081       while (n_left_from > 0 && n_left_to_next > 0)
1082         {
1083           u32 bi0;
1084           vlib_buffer_t *b0;
1085           u32 next0 = SNAT_OUT2IN_NEXT_LOOKUP;
1086           u32 sw_if_index0;
1087           ip4_header_t *ip0;
1088           ip_csum_t sum0;
1089           u32 new_addr0, old_addr0;
1090           u16 new_port0, old_port0;
1091           udp_header_t *udp0;
1092           tcp_header_t *tcp0;
1093           icmp46_header_t *icmp0;
1094           snat_session_key_t key0, sm0;
1095           u32 rx_fib_index0;
1096           u32 proto0;
1097           snat_session_t *s0 = 0;
1098           clib_bihash_kv_8_8_t kv0, value0;
1099           u8 identity_nat0;
1100
1101           /* speculatively enqueue b0 to the current next frame */
1102           bi0 = from[0];
1103           to_next[0] = bi0;
1104           from += 1;
1105           to_next += 1;
1106           n_left_from -= 1;
1107           n_left_to_next -= 1;
1108
1109           b0 = vlib_get_buffer (vm, bi0);
1110
1111           vnet_buffer (b0)->snat.flags = 0;
1112
1113           ip0 = vlib_buffer_get_current (b0);
1114           udp0 = ip4_next_header (ip0);
1115           tcp0 = (tcp_header_t *) udp0;
1116           icmp0 = (icmp46_header_t *) udp0;
1117
1118           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1119           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1120                                    sw_if_index0);
1121
1122           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1123
1124           if (PREDICT_FALSE (proto0 == ~0))
1125             {
1126               if (nat_out2in_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
1127                 {
1128                   if (!sm->forwarding_enabled)
1129                     {
1130                       b0->error =
1131                         node->errors[SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL];
1132                       next0 = SNAT_OUT2IN_NEXT_DROP;
1133                     }
1134                 }
1135               goto trace00;
1136             }
1137
1138           if (PREDICT_FALSE (ip0->ttl == 1))
1139             {
1140               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1141               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1142                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1143                                            0);
1144               next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR;
1145               goto trace00;
1146             }
1147
1148           if (PREDICT_FALSE (ip4_is_fragment (ip0)))
1149             {
1150               next0 = SNAT_OUT2IN_NEXT_REASS;
1151               goto trace00;
1152             }
1153
1154           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1155             {
1156               next0 = icmp_out2in_slow_path
1157                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1158                  next0, now, thread_index, &s0);
1159               goto trace00;
1160             }
1161
1162           key0.addr = ip0->dst_address;
1163           key0.port = udp0->dst_port;
1164           key0.protocol = proto0;
1165           key0.fib_index = rx_fib_index0;
1166
1167           kv0.key = key0.as_u64;
1168
1169           if (clib_bihash_search_8_8
1170               (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
1171             {
1172               /* Try to match static mapping by external address and port,
1173                  destination address and port in packet */
1174               if (snat_static_mapping_match
1175                   (sm, key0, &sm0, 1, 0, 0, 0, 0, &identity_nat0))
1176                 {
1177                   /*
1178                    * Send DHCP packets to the ipv4 stack, or we won't
1179                    * be able to use dhcp client on the outside interface
1180                    */
1181                   if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1182                                      && (udp0->dst_port ==
1183                                          clib_host_to_net_u16
1184                                          (UDP_DST_PORT_dhcp_to_client))))
1185                     {
1186                       vnet_feature_next (&next0, b0);
1187                       goto trace00;
1188                     }
1189
1190                   if (!sm->forwarding_enabled)
1191                     {
1192                       b0->error =
1193                         node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
1194                       next0 = SNAT_OUT2IN_NEXT_DROP;
1195                     }
1196                   goto trace00;
1197                 }
1198
1199               if (PREDICT_FALSE (identity_nat0))
1200                 goto trace00;
1201
1202               /* Create session initiated by host from external network */
1203               s0 = create_session_for_static_mapping (sm, b0, sm0, key0, node,
1204                                                       thread_index, now);
1205               if (!s0)
1206                 {
1207                   next0 = SNAT_OUT2IN_NEXT_DROP;
1208                   goto trace00;
1209                 }
1210             }
1211           else
1212             s0 =
1213               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1214                                  value0.value);
1215
1216           old_addr0 = ip0->dst_address.as_u32;
1217           ip0->dst_address = s0->in2out.addr;
1218           new_addr0 = ip0->dst_address.as_u32;
1219           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1220
1221           sum0 = ip0->checksum;
1222           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1223                                  ip4_header_t,
1224                                  dst_address /* changed member */ );
1225           ip0->checksum = ip_csum_fold (sum0);
1226
1227           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1228             {
1229               old_port0 = tcp0->dst_port;
1230               tcp0->dst_port = s0->in2out.port;
1231               new_port0 = tcp0->dst_port;
1232
1233               sum0 = tcp0->checksum;
1234               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1235                                      ip4_header_t,
1236                                      dst_address /* changed member */ );
1237
1238               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1239                                      ip4_header_t /* cheat */ ,
1240                                      length /* changed member */ );
1241               tcp0->checksum = ip_csum_fold (sum0);
1242             }
1243           else
1244             {
1245               old_port0 = udp0->dst_port;
1246               udp0->dst_port = s0->in2out.port;
1247               udp0->checksum = 0;
1248             }
1249
1250           /* Accounting */
1251           nat44_session_update_counters (s0, now,
1252                                          vlib_buffer_length_in_chain (vm,
1253                                                                       b0));
1254           /* Per-user LRU list maintenance */
1255           nat44_session_update_lru (sm, s0, thread_index);
1256         trace00:
1257
1258           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1259                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1260             {
1261               snat_out2in_trace_t *t =
1262                 vlib_add_trace (vm, node, b0, sizeof (*t));
1263               t->sw_if_index = sw_if_index0;
1264               t->next_index = next0;
1265               t->session_index = ~0;
1266               if (s0)
1267                 t->session_index =
1268                   s0 - sm->per_thread_data[thread_index].sessions;
1269             }
1270
1271           pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;
1272
1273           /* verify speculative enqueue, maybe switch current next frame */
1274           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1275                                            to_next, n_left_to_next,
1276                                            bi0, next0);
1277         }
1278
1279       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1280     }
1281
1282   vlib_node_increment_counter (vm, snat_out2in_node.index,
1283                                SNAT_OUT2IN_ERROR_OUT2IN_PACKETS,
1284                                pkts_processed);
1285   return frame->n_vectors;
1286 }
1287
1288 /* *INDENT-OFF* */
1289 VLIB_REGISTER_NODE (snat_out2in_node) = {
1290   .function = snat_out2in_node_fn,
1291   .name = "nat44-out2in",
1292   .vector_size = sizeof (u32),
1293   .format_trace = format_snat_out2in_trace,
1294   .type = VLIB_NODE_TYPE_INTERNAL,
1295
1296   .n_errors = ARRAY_LEN(snat_out2in_error_strings),
1297   .error_strings = snat_out2in_error_strings,
1298
1299   .runtime_data_bytes = sizeof (snat_runtime_t),
1300
1301   .n_next_nodes = SNAT_OUT2IN_N_NEXT,
1302
1303   /* edit / add dispositions here */
1304   .next_nodes = {
1305     [SNAT_OUT2IN_NEXT_DROP] = "error-drop",
1306     [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
1307     [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1308     [SNAT_OUT2IN_NEXT_REASS] = "nat44-out2in-reass",
1309   },
1310 };
1311 /* *INDENT-ON* */
1312
1313 VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_node, snat_out2in_node_fn);
1314
1315 static uword
1316 nat44_out2in_reass_node_fn (vlib_main_t * vm,
1317                             vlib_node_runtime_t * node, vlib_frame_t * frame)
1318 {
1319   u32 n_left_from, *from, *to_next;
1320   snat_out2in_next_t next_index;
1321   u32 pkts_processed = 0;
1322   snat_main_t *sm = &snat_main;
1323   f64 now = vlib_time_now (vm);
1324   u32 thread_index = vm->thread_index;
1325   snat_main_per_thread_data_t *per_thread_data =
1326     &sm->per_thread_data[thread_index];
1327   u32 *fragments_to_drop = 0;
1328   u32 *fragments_to_loopback = 0;
1329
1330   from = vlib_frame_vector_args (frame);
1331   n_left_from = frame->n_vectors;
1332   next_index = node->cached_next_index;
1333
1334   while (n_left_from > 0)
1335     {
1336       u32 n_left_to_next;
1337
1338       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1339
1340       while (n_left_from > 0 && n_left_to_next > 0)
1341         {
1342           u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1343           vlib_buffer_t *b0;
1344           u32 next0;
1345           u8 cached0 = 0;
1346           ip4_header_t *ip0;
1347           nat_reass_ip4_t *reass0;
1348           udp_header_t *udp0;
1349           tcp_header_t *tcp0;
1350           icmp46_header_t *icmp0;
1351           snat_session_key_t key0, sm0;
1352           clib_bihash_kv_8_8_t kv0, value0;
1353           snat_session_t *s0 = 0;
1354           u16 old_port0, new_port0;
1355           ip_csum_t sum0;
1356           u8 identity_nat0;
1357
1358           /* speculatively enqueue b0 to the current next frame */
1359           bi0 = from[0];
1360           to_next[0] = bi0;
1361           from += 1;
1362           to_next += 1;
1363           n_left_from -= 1;
1364           n_left_to_next -= 1;
1365
1366           b0 = vlib_get_buffer (vm, bi0);
1367           next0 = SNAT_OUT2IN_NEXT_LOOKUP;
1368
1369           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1370           rx_fib_index0 =
1371             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1372                                                  sw_if_index0);
1373
1374           if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1375             {
1376               next0 = SNAT_OUT2IN_NEXT_DROP;
1377               b0->error = node->errors[SNAT_OUT2IN_ERROR_DROP_FRAGMENT];
1378               goto trace0;
1379             }
1380
1381           ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
1382           udp0 = ip4_next_header (ip0);
1383           tcp0 = (tcp_header_t *) udp0;
1384           icmp0 = (icmp46_header_t *) udp0;
1385           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1386
1387           reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1388                                                  ip0->dst_address,
1389                                                  ip0->fragment_id,
1390                                                  ip0->protocol,
1391                                                  1, &fragments_to_drop);
1392
1393           if (PREDICT_FALSE (!reass0))
1394             {
1395               next0 = SNAT_OUT2IN_NEXT_DROP;
1396               b0->error = node->errors[SNAT_OUT2IN_ERROR_MAX_REASS];
1397               nat_log_notice ("maximum reassemblies exceeded");
1398               goto trace0;
1399             }
1400
1401           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1402             {
1403               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1404                 {
1405                   next0 = icmp_out2in_slow_path
1406                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1407                      next0, now, thread_index, &s0);
1408
1409                   if (PREDICT_TRUE (next0 != SNAT_OUT2IN_NEXT_DROP))
1410                     {
1411                       if (s0)
1412                         reass0->sess_index = s0 - per_thread_data->sessions;
1413                       else
1414                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1415                       reass0->thread_index = thread_index;
1416                       nat_ip4_reass_get_frags (reass0,
1417                                                &fragments_to_loopback);
1418                     }
1419
1420                   goto trace0;
1421                 }
1422
1423               key0.addr = ip0->dst_address;
1424               key0.port = udp0->dst_port;
1425               key0.protocol = proto0;
1426               key0.fib_index = rx_fib_index0;
1427               kv0.key = key0.as_u64;
1428
1429               if (clib_bihash_search_8_8
1430                   (&per_thread_data->out2in, &kv0, &value0))
1431                 {
1432                   /* Try to match static mapping by external address and port,
1433                      destination address and port in packet */
1434                   if (snat_static_mapping_match
1435                       (sm, key0, &sm0, 1, 0, 0, 0, 0, &identity_nat0))
1436                     {
1437                       /*
1438                        * Send DHCP packets to the ipv4 stack, or we won't
1439                        * be able to use dhcp client on the outside interface
1440                        */
1441                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1442                                          && (udp0->dst_port
1443                                              ==
1444                                              clib_host_to_net_u16
1445                                              (UDP_DST_PORT_dhcp_to_client))))
1446                         {
1447                           vnet_feature_next (&next0, b0);
1448                           goto trace0;
1449                         }
1450
1451                       if (!sm->forwarding_enabled)
1452                         {
1453                           b0->error =
1454                             node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
1455                           next0 = SNAT_OUT2IN_NEXT_DROP;
1456                         }
1457                       else
1458                         {
1459                           reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1460                           nat_ip4_reass_get_frags (reass0,
1461                                                    &fragments_to_loopback);
1462                         }
1463                       goto trace0;
1464                     }
1465
1466                   if (PREDICT_FALSE (identity_nat0))
1467                     goto trace0;
1468
1469                   /* Create session initiated by host from external network */
1470                   s0 =
1471                     create_session_for_static_mapping (sm, b0, sm0, key0,
1472                                                        node, thread_index,
1473                                                        now);
1474                   if (!s0)
1475                     {
1476                       b0->error =
1477                         node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
1478                       next0 = SNAT_OUT2IN_NEXT_DROP;
1479                       goto trace0;
1480                     }
1481                   reass0->sess_index = s0 - per_thread_data->sessions;
1482                   reass0->thread_index = thread_index;
1483                 }
1484               else
1485                 {
1486                   s0 = pool_elt_at_index (per_thread_data->sessions,
1487                                           value0.value);
1488                   reass0->sess_index = value0.value;
1489                 }
1490               nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1491             }
1492           else
1493             {
1494               if (reass0->flags & NAT_REASS_FLAG_ED_DONT_TRANSLATE)
1495                 goto trace0;
1496               if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1497                 {
1498                   if (nat_ip4_reass_add_fragment
1499                       (reass0, bi0, &fragments_to_drop))
1500                     {
1501                       b0->error = node->errors[SNAT_OUT2IN_ERROR_MAX_FRAG];
1502                       nat_log_notice
1503                         ("maximum fragments per reassembly exceeded");
1504                       next0 = SNAT_OUT2IN_NEXT_DROP;
1505                       goto trace0;
1506                     }
1507                   cached0 = 1;
1508                   goto trace0;
1509                 }
1510               s0 = pool_elt_at_index (per_thread_data->sessions,
1511                                       reass0->sess_index);
1512             }
1513
1514           old_addr0 = ip0->dst_address.as_u32;
1515           ip0->dst_address = s0->in2out.addr;
1516           new_addr0 = ip0->dst_address.as_u32;
1517           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1518
1519           sum0 = ip0->checksum;
1520           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1521                                  ip4_header_t,
1522                                  dst_address /* changed member */ );
1523           ip0->checksum = ip_csum_fold (sum0);
1524
1525           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1526             {
1527               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1528                 {
1529                   old_port0 = tcp0->dst_port;
1530                   tcp0->dst_port = s0->in2out.port;
1531                   new_port0 = tcp0->dst_port;
1532
1533                   sum0 = tcp0->checksum;
1534                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1535                                          ip4_header_t,
1536                                          dst_address /* changed member */ );
1537
1538                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1539                                          ip4_header_t /* cheat */ ,
1540                                          length /* changed member */ );
1541                   tcp0->checksum = ip_csum_fold (sum0);
1542                 }
1543               else
1544                 {
1545                   old_port0 = udp0->dst_port;
1546                   udp0->dst_port = s0->in2out.port;
1547                   udp0->checksum = 0;
1548                 }
1549             }
1550
1551           /* Accounting */
1552           nat44_session_update_counters (s0, now,
1553                                          vlib_buffer_length_in_chain (vm,
1554                                                                       b0));
1555           /* Per-user LRU list maintenance */
1556           nat44_session_update_lru (sm, s0, thread_index);
1557
1558         trace0:
1559           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1560                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1561             {
1562               nat44_reass_trace_t *t =
1563                 vlib_add_trace (vm, node, b0, sizeof (*t));
1564               t->cached = cached0;
1565               t->sw_if_index = sw_if_index0;
1566               t->next_index = next0;
1567             }
1568
1569           if (cached0)
1570             {
1571               n_left_to_next++;
1572               to_next--;
1573             }
1574           else
1575             {
1576               pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;
1577
1578               /* verify speculative enqueue, maybe switch current next frame */
1579               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1580                                                to_next, n_left_to_next,
1581                                                bi0, next0);
1582             }
1583
1584           if (n_left_from == 0 && vec_len (fragments_to_loopback))
1585             {
1586               from = vlib_frame_vector_args (frame);
1587               u32 len = vec_len (fragments_to_loopback);
1588               if (len <= VLIB_FRAME_SIZE)
1589                 {
1590                   clib_memcpy_fast (from, fragments_to_loopback,
1591                                     sizeof (u32) * len);
1592                   n_left_from = len;
1593                   vec_reset_length (fragments_to_loopback);
1594                 }
1595               else
1596                 {
1597                   clib_memcpy_fast (from, fragments_to_loopback +
1598                                     (len - VLIB_FRAME_SIZE),
1599                                     sizeof (u32) * VLIB_FRAME_SIZE);
1600                   n_left_from = VLIB_FRAME_SIZE;
1601                   _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
1602                 }
1603             }
1604         }
1605
1606       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1607     }
1608
1609   vlib_node_increment_counter (vm, nat44_out2in_reass_node.index,
1610                                SNAT_OUT2IN_ERROR_OUT2IN_PACKETS,
1611                                pkts_processed);
1612
1613   nat_send_all_to_node (vm, fragments_to_drop, node,
1614                         &node->errors[SNAT_OUT2IN_ERROR_DROP_FRAGMENT],
1615                         SNAT_OUT2IN_NEXT_DROP);
1616
1617   vec_free (fragments_to_drop);
1618   vec_free (fragments_to_loopback);
1619   return frame->n_vectors;
1620 }
1621
1622 /* *INDENT-OFF* */
1623 VLIB_REGISTER_NODE (nat44_out2in_reass_node) = {
1624   .function = nat44_out2in_reass_node_fn,
1625   .name = "nat44-out2in-reass",
1626   .vector_size = sizeof (u32),
1627   .format_trace = format_nat44_reass_trace,
1628   .type = VLIB_NODE_TYPE_INTERNAL,
1629
1630   .n_errors = ARRAY_LEN(snat_out2in_error_strings),
1631   .error_strings = snat_out2in_error_strings,
1632
1633   .n_next_nodes = SNAT_OUT2IN_N_NEXT,
1634
1635   /* edit / add dispositions here */
1636   .next_nodes = {
1637     [SNAT_OUT2IN_NEXT_DROP] = "error-drop",
1638     [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
1639     [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1640     [SNAT_OUT2IN_NEXT_REASS] = "nat44-out2in-reass",
1641   },
1642 };
1643 /* *INDENT-ON* */
1644
1645 VLIB_NODE_FUNCTION_MULTIARCH (nat44_out2in_reass_node,
1646                               nat44_out2in_reass_node_fn);
1647
1648 static uword
1649 snat_out2in_fast_node_fn (vlib_main_t * vm,
1650                           vlib_node_runtime_t * node, vlib_frame_t * frame)
1651 {
1652   u32 n_left_from, *from, *to_next;
1653   snat_out2in_next_t next_index;
1654   u32 pkts_processed = 0;
1655   snat_main_t *sm = &snat_main;
1656
1657   from = vlib_frame_vector_args (frame);
1658   n_left_from = frame->n_vectors;
1659   next_index = node->cached_next_index;
1660
1661   while (n_left_from > 0)
1662     {
1663       u32 n_left_to_next;
1664
1665       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1666
1667       while (n_left_from > 0 && n_left_to_next > 0)
1668         {
1669           u32 bi0;
1670           vlib_buffer_t *b0;
1671           u32 next0 = SNAT_OUT2IN_NEXT_DROP;
1672           u32 sw_if_index0;
1673           ip4_header_t *ip0;
1674           ip_csum_t sum0;
1675           u32 new_addr0, old_addr0;
1676           u16 new_port0, old_port0;
1677           udp_header_t *udp0;
1678           tcp_header_t *tcp0;
1679           icmp46_header_t *icmp0;
1680           snat_session_key_t key0, sm0;
1681           u32 proto0;
1682           u32 rx_fib_index0;
1683
1684           /* speculatively enqueue b0 to the current next frame */
1685           bi0 = from[0];
1686           to_next[0] = bi0;
1687           from += 1;
1688           to_next += 1;
1689           n_left_from -= 1;
1690           n_left_to_next -= 1;
1691
1692           b0 = vlib_get_buffer (vm, bi0);
1693
1694           ip0 = vlib_buffer_get_current (b0);
1695           udp0 = ip4_next_header (ip0);
1696           tcp0 = (tcp_header_t *) udp0;
1697           icmp0 = (icmp46_header_t *) udp0;
1698
1699           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1700           rx_fib_index0 =
1701             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
1702
1703           vnet_feature_next (&next0, b0);
1704
1705           if (PREDICT_FALSE (ip0->ttl == 1))
1706             {
1707               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1708               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1709                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1710                                            0);
1711               next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR;
1712               goto trace00;
1713             }
1714
1715           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1716
1717           if (PREDICT_FALSE (proto0 == ~0))
1718             goto trace00;
1719
1720           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1721             {
1722               next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0,
1723                                    rx_fib_index0, node, next0, ~0, 0, 0);
1724               goto trace00;
1725             }
1726
1727           key0.addr = ip0->dst_address;
1728           key0.port = udp0->dst_port;
1729           key0.fib_index = rx_fib_index0;
1730
1731           if (snat_static_mapping_match (sm, key0, &sm0, 1, 0, 0, 0, 0, 0))
1732             {
1733               b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
1734               goto trace00;
1735             }
1736
1737           new_addr0 = sm0.addr.as_u32;
1738           new_port0 = sm0.port;
1739           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
1740           old_addr0 = ip0->dst_address.as_u32;
1741           ip0->dst_address.as_u32 = new_addr0;
1742
1743           sum0 = ip0->checksum;
1744           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1745                                  ip4_header_t,
1746                                  dst_address /* changed member */ );
1747           ip0->checksum = ip_csum_fold (sum0);
1748
1749           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
1750             {
1751               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1752                 {
1753                   old_port0 = tcp0->dst_port;
1754                   tcp0->dst_port = new_port0;
1755
1756                   sum0 = tcp0->checksum;
1757                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1758                                          ip4_header_t,
1759                                          dst_address /* changed member */ );
1760
1761                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1762                                          ip4_header_t /* cheat */ ,
1763                                          length /* changed member */ );
1764                   tcp0->checksum = ip_csum_fold (sum0);
1765                 }
1766               else
1767                 {
1768                   old_port0 = udp0->dst_port;
1769                   udp0->dst_port = new_port0;
1770                   udp0->checksum = 0;
1771                 }
1772             }
1773           else
1774             {
1775               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1776                 {
1777                   sum0 = tcp0->checksum;
1778                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1779                                          ip4_header_t,
1780                                          dst_address /* changed member */ );
1781
1782                   tcp0->checksum = ip_csum_fold (sum0);
1783                 }
1784             }
1785
1786         trace00:
1787
1788           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1789                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1790             {
1791               snat_out2in_trace_t *t =
1792                 vlib_add_trace (vm, node, b0, sizeof (*t));
1793               t->sw_if_index = sw_if_index0;
1794               t->next_index = next0;
1795             }
1796
1797           pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;
1798
1799           /* verify speculative enqueue, maybe switch current next frame */
1800           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1801                                            to_next, n_left_to_next,
1802                                            bi0, next0);
1803         }
1804
1805       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1806     }
1807
1808   vlib_node_increment_counter (vm, snat_out2in_fast_node.index,
1809                                SNAT_OUT2IN_ERROR_OUT2IN_PACKETS,
1810                                pkts_processed);
1811   return frame->n_vectors;
1812 }
1813
1814 /* *INDENT-OFF* */
1815 VLIB_REGISTER_NODE (snat_out2in_fast_node) = {
1816   .function = snat_out2in_fast_node_fn,
1817   .name = "nat44-out2in-fast",
1818   .vector_size = sizeof (u32),
1819   .format_trace = format_snat_out2in_fast_trace,
1820   .type = VLIB_NODE_TYPE_INTERNAL,
1821
1822   .n_errors = ARRAY_LEN(snat_out2in_error_strings),
1823   .error_strings = snat_out2in_error_strings,
1824
1825   .runtime_data_bytes = sizeof (snat_runtime_t),
1826
1827   .n_next_nodes = SNAT_OUT2IN_N_NEXT,
1828
1829   /* edit / add dispositions here */
1830   .next_nodes = {
1831     [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
1832     [SNAT_OUT2IN_NEXT_DROP] = "error-drop",
1833     [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1834     [SNAT_OUT2IN_NEXT_REASS] = "nat44-out2in-reass",
1835   },
1836 };
1837 /* *INDENT-ON* */
1838
1839 VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_fast_node,
1840                               snat_out2in_fast_node_fn);
1841
1842 /*
1843  * fd.io coding-style-patch-verification: ON
1844  *
1845  * Local Variables:
1846  * eval: (c-set-style "gnu")
1847  * End:
1848  */