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authorPeter Mikus <pmikus@cisco.com>2019-09-11 11:19:27 +0000
committerPeter Mikus <pmikus@cisco.com>2019-09-12 07:10:34 +0000
commit6a80c9028d71a1502a2f2a64b4646af4c5958733 (patch)
treeeae7a91f17c5677dcdf3e36356e8ab5bb64fa5be /resources/libraries
parent45882a2701df2349b3f53b8436aec530cbeeb614 (diff)
TRex: 2.61
- HDRhistogram can be rebased and used in separate patch. Signed-off-by: Peter Mikus <pmikus@cisco.com> Change-Id: Ic7ce752344c6e1791af7cf7b7effde65ac2be680
Diffstat (limited to 'resources/libraries')
-rw-r--r--resources/libraries/python/Constants.py5
-rw-r--r--resources/libraries/python/TrafficGenerator.py3
2 files changed, 3 insertions, 5 deletions
diff --git a/resources/libraries/python/Constants.py b/resources/libraries/python/Constants.py
index b7f91930cb..9dd9a38e17 100644
--- a/resources/libraries/python/Constants.py
+++ b/resources/libraries/python/Constants.py
@@ -184,11 +184,8 @@ class Constants(object):
# Docker container arm SUT image
DOCKER_SUT_IMAGE_UBUNTU_ARM = 'snergster/csit-arm-sut:latest'
- # TRex install version
- TREX_INSTALL_VERSION = '2.54'
-
# TRex install directory
- TREX_INSTALL_DIR = '/opt/trex-core-2.54'
+ TREX_INSTALL_DIR = '/opt/trex-core-2.61'
# Honeycomb directory location at topology nodes:
REMOTE_HC_DIR = '/opt/honeycomb'
diff --git a/resources/libraries/python/TrafficGenerator.py b/resources/libraries/python/TrafficGenerator.py
index f2fac256fc..2e59459773 100644
--- a/resources/libraries/python/TrafficGenerator.py
+++ b/resources/libraries/python/TrafficGenerator.py
@@ -323,7 +323,8 @@ class TrafficGenerator(AbstractMeasurer):
self._node, cmd, sudo=True,
message='Unbind PCI ports from driver failed!')
- cmd = ("sh -c 'cd {dir}/scripts/ && ./trex-cfg'"
+ cmd = ("sh -c 'cd {dir}/scripts/ && ./trex-cfg "
+ "--unbind-unused-ports'"
.format(dir=Constants.TREX_INSTALL_DIR))
exec_cmd_no_error(
self._node, cmd, sudo=True, message='Config TRex failed!')
id='n426' href='#n426'>426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 
/*
 * Copyright (c) 2016 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vnet/pg/pg.h>
#include <vnet/handoff.h>

#include <vnet/ip/ip.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/fib/ip4_fib.h>
#include <snat/snat.h>
#include <snat/snat_ipfix_logging.h>

#include <vppinfra/hash.h>
#include <vppinfra/error.h>
#include <vppinfra/elog.h>

typedef struct {
  u32 sw_if_index;
  u32 next_index;
  u32 session_index;
} snat_out2in_trace_t;

typedef struct {
  u32 next_worker_index;
  u8 do_handoff;
} snat_out2in_worker_handoff_trace_t;

/* packet trace format function */
static u8 * format_snat_out2in_trace (u8 * s, va_list * args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  snat_out2in_trace_t * t = va_arg (*args, snat_out2in_trace_t *);
  
  s = format (s, "SNAT_OUT2IN: sw_if_index %d, next index %d, session index %d",
              t->sw_if_index, t->next_index, t->session_index);
  return s;
}

static u8 * format_snat_out2in_fast_trace (u8 * s, va_list * args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  snat_out2in_trace_t * t = va_arg (*args, snat_out2in_trace_t *);
  
  s = format (s, "SNAT_OUT2IN_FAST: sw_if_index %d, next index %d",
              t->sw_if_index, t->next_index);
  return s;
}

static u8 * format_snat_out2in_worker_handoff_trace (u8 * s, va_list * args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  snat_out2in_worker_handoff_trace_t * t =
    va_arg (*args, snat_out2in_worker_handoff_trace_t *);
  char * m;

  m = t->do_handoff ? "next worker" : "same worker";
  s = format (s, "SNAT_OUT2IN_WORKER_HANDOFF: %s %d", m, t->next_worker_index);

  return s;
}

vlib_node_registration_t snat_out2in_node;
vlib_node_registration_t snat_out2in_fast_node;
vlib_node_registration_t snat_out2in_worker_handoff_node;

#define foreach_snat_out2in_error                       \
_(UNSUPPORTED_PROTOCOL, "Unsupported protocol")         \
_(OUT2IN_PACKETS, "Good out2in packets processed")      \
_(BAD_ICMP_TYPE, "icmp type not echo-reply")            \
_(NO_TRANSLATION, "No translation")
  
typedef enum {
#define _(sym,str) SNAT_OUT2IN_ERROR_##sym,
  foreach_snat_out2in_error
#undef _
  SNAT_OUT2IN_N_ERROR,
} snat_out2in_error_t;

static char * snat_out2in_error_strings[] = {
#define _(sym,string) string,
  foreach_snat_out2in_error
#undef _
};

typedef enum {
  SNAT_OUT2IN_NEXT_DROP,
  SNAT_OUT2IN_NEXT_LOOKUP,
  SNAT_OUT2IN_N_NEXT,
} snat_out2in_next_t;

/**
 * @brief Create session for static mapping.
 *
 * Create NAT session initiated by host from external network with static
 * mapping.
 *
 * @param sm     SNAT main.
 * @param b0     Vlib buffer.
 * @param in2out In2out SNAT session key.
 * @param out2in Out2in SNAT session key.
 * @param node   Vlib node.
 *
 * @returns SNAT session if successfully created otherwise 0.
 */
static inline snat_session_t *
create_session_for_static_mapping (snat_main_t *sm,
                                   vlib_buffer_t *b0,
                                   snat_session_key_t in2out,
                                   snat_session_key_t out2in,
                                   vlib_node_runtime_t * node,
                                   u32 cpu_index)
{
  snat_user_t *u;
  snat_user_key_t user_key;
  snat_session_t *s;
  clib_bihash_kv_8_8_t kv0, value0;
  dlist_elt_t * per_user_translation_list_elt;
  dlist_elt_t * per_user_list_head_elt;

  user_key.addr = in2out.addr;
  user_key.fib_index = in2out.fib_index;
  kv0.key = user_key.as_u64;

  /* Ever heard of the "user" = inside ip4 address before? */
  if (clib_bihash_search_8_8 (&sm->user_hash, &kv0, &value0))
    {
      /* no, make a new one */
      pool_get (sm->per_thread_data[cpu_index].users, u);
      memset (u, 0, sizeof (*u));
      u->addr = in2out.addr;

      pool_get (sm->per_thread_data[cpu_index].list_pool,
                per_user_list_head_elt);

      u->sessions_per_user_list_head_index = per_user_list_head_elt -
        sm->per_thread_data[cpu_index].list_pool;

      clib_dlist_init (sm->per_thread_data[cpu_index].list_pool,
                       u->sessions_per_user_list_head_index);

      kv0.value = u - sm->per_thread_data[cpu_index].users;

      /* add user */
      clib_bihash_add_del_8_8 (&sm->user_hash, &kv0, 1 /* is_add */);

      /* add non-traslated packets worker lookup */
      kv0.value = cpu_index;
      clib_bihash_add_del_8_8 (&sm->worker_by_in, &kv0, 1);
    }
  else
    {
      u = pool_elt_at_index (sm->per_thread_data[cpu_index].users,
                             value0.value);
    }

  pool_get (sm->per_thread_data[cpu_index].sessions, s);
  memset (s, 0, sizeof (*s));

  s->outside_address_index = ~0;
  s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
  u->nstaticsessions++;

  /* Create list elts */
  pool_get (sm->per_thread_data[cpu_index].list_pool,
            per_user_translation_list_elt);
  clib_dlist_init (sm->per_thread_data[cpu_index].list_pool,
                   per_user_translation_list_elt -
                   sm->per_thread_data[cpu_index].list_pool);

  per_user_translation_list_elt->value =
    s - sm->per_thread_data[cpu_index].sessions;
  s->per_user_index =
    per_user_translation_list_elt - sm->per_thread_data[cpu_index].list_pool;
  s->per_user_list_head_index = u->sessions_per_user_list_head_index;

  clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool,
                      s->per_user_list_head_index,
                      per_user_translation_list_elt -
                      sm->per_thread_data[cpu_index].list_pool);

  s->in2out = in2out;
  s->out2in = out2in;
  s->in2out.protocol = out2in.protocol;

  /* Add to translation hashes */
  kv0.key = s->in2out.as_u64;
  kv0.value = s - sm->per_thread_data[cpu_index].sessions;
  if (clib_bihash_add_del_8_8 (&sm->in2out, &kv0, 1 /* is_add */))
      clib_warning ("in2out key add failed");

  kv0.key = s->out2in.as_u64;
  kv0.value = s - sm->per_thread_data[cpu_index].sessions;

  if (clib_bihash_add_del_8_8 (&sm->out2in, &kv0, 1 /* is_add */))
      clib_warning ("out2in key add failed");

  /* log NAT event */
  snat_ipfix_logging_nat44_ses_create(s->in2out.addr.as_u32,
                                      s->out2in.addr.as_u32,
                                      s->in2out.protocol,
                                      s->in2out.port,
                                      s->out2in.port,
                                      s->in2out.fib_index);
   return s;
}

static inline u32 icmp_out2in_slow_path (snat_main_t *sm,
                                         vlib_buffer_t * b0,
                                         ip4_header_t * ip0,
                                         icmp46_header_t * icmp0,
                                         u32 sw_if_index0,
                                         u32 rx_fib_index0,
                                         vlib_node_runtime_t * node,
                                         u32 next0, f64 now,
                                         u32 cpu_index)
{
  snat_session_key_t key0, sm0;
  icmp_echo_header_t *echo0;
  clib_bihash_kv_8_8_t kv0, value0;
  snat_session_t * s0;
  u32 new_addr0, old_addr0;
  u16 old_id0, new_id0;
  ip_csum_t sum0;
  snat_runtime_t * rt = (snat_runtime_t *)node->runtime_data;

  echo0 = (icmp_echo_header_t *)(icmp0+1);

  key0.addr = ip0->dst_address;
  key0.port = echo0->identifier;
  key0.protocol = SNAT_PROTOCOL_ICMP;
  key0.fib_index = rx_fib_index0;
  
  kv0.key = key0.as_u64;
  
  if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0))
    {
      /* Try to match static mapping by external address and port,
         destination address and port in packet */
      if (snat_static_mapping_match(sm, key0, &sm0, 1))
        {
           ip4_address_t * first_int_addr;

          if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0))
            {
              first_int_addr = 
                ip4_interface_first_address (sm->ip4_main, sw_if_index0,
                                             0 /* just want the address */);
              rt->cached_sw_if_index = sw_if_index0;
              if (first_int_addr)
                rt->cached_ip4_address = first_int_addr->as_u32;
              else
                rt->cached_ip4_address = 0;
            }
          
          /* Don't NAT packet aimed at the intfc address */
          if (PREDICT_FALSE(ip0->dst_address.as_u32 ==
                            rt->cached_ip4_address))
            return next0;

          b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
          return SNAT_OUT2IN_NEXT_DROP;
        }

      /* Create session initiated by host from external network */
      s0 = create_session_for_static_mapping(sm, b0, sm0, key0,
                                             node, cpu_index);
      if (!s0)
        return SNAT_OUT2IN_NEXT_DROP;
    }
  else
    s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions,
                            value0.value);

  old_addr0 = ip0->dst_address.as_u32;
  ip0->dst_address = s0->in2out.addr;
  new_addr0 = ip0->dst_address.as_u32;
  vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
  
  sum0 = ip0->checksum;
  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                         ip4_header_t,
                         dst_address /* changed member */);
  ip0->checksum = ip_csum_fold (sum0);
  
  old_id0 = echo0->identifier;
  new_id0 = s0->in2out.port;
  echo0->identifier = new_id0;

  sum0 = icmp0->checksum;
  sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
                         identifier);
  icmp0->checksum = ip_csum_fold (sum0);

  /* Accounting */
  s0->last_heard = now;
  s0->total_pkts++;
  s0->total_bytes += vlib_buffer_length_in_chain (sm->vlib_main, b0);
  /* Per-user LRU list maintenance for dynamic translation */
  if (!snat_is_session_static (s0))
    {
      clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool,
                         s0->per_user_index);
      clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool,
                          s0->per_user_list_head_index,
                          s0->per_user_index);
    }

  return next0;
}

static uword
snat_out2in_node_fn (vlib_main_t * vm,
		  vlib_node_runtime_t * node,
		  vlib_frame_t * frame)
{
  u32 n_left_from, * from, * to_next;
  snat_out2in_next_t next_index;
  u32 pkts_processed = 0;
  snat_main_t * sm = &snat_main;
  f64 now = vlib_time_now (vm);
  u32 cpu_index = os_get_cpu_number ();

  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;

  while (n_left_from > 0)
    {
      u32 n_left_to_next;

      vlib_get_next_frame (vm, node, next_index,
			   to_next, n_left_to_next);

      while (n_left_from >= 4 && n_left_to_next >= 2)
	{
          u32 bi0, bi1;
	  vlib_buffer_t * b0, * b1;
          u32 next0 = SNAT_OUT2IN_NEXT_LOOKUP;
          u32 next1 = SNAT_OUT2IN_NEXT_LOOKUP;
          u32 sw_if_index0, sw_if_index1;
          ip4_header_t * ip0, *ip1;
          ip_csum_t sum0, sum1;
          u32 new_addr0, old_addr0;
          u16 new_port0, old_port0;
          u32 new_addr1, old_addr1;
          u16 new_port1, old_port1;
          udp_header_t * udp0, * udp1;
          tcp_header_t * tcp0, * tcp1;
          icmp46_header_t * icmp0, * icmp1;
          snat_session_key_t key0, key1, sm0, sm1;
          u32 rx_fib_index0, rx_fib_index1;
          u32 proto0, proto1;
          snat_session_t * s0 = 0, * s1 = 0;
          clib_bihash_kv_8_8_t kv0, kv1, value0, value1;
          
	  /* Prefetch next iteration. */
	  {
	    vlib_buffer_t * p2, * p3;
            
	    p2 = vlib_get_buffer (vm, from[2]);
	    p3 = vlib_get_buffer (vm, from[3]);
            
	    vlib_prefetch_buffer_header (p2, LOAD);
	    vlib_prefetch_buffer_header (p3, LOAD);

	    CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
	    CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
	  }

          /* speculatively enqueue b0 and b1 to the current next frame */
	  to_next[0] = bi0 = from[0];
	  to_next[1] = bi1 = from[1];
	  from += 2;
	  to_next += 2;
	  n_left_from -= 2;
	  n_left_to_next -= 2;

	  b0 = vlib_get_buffer (vm, bi0);
	  b1 = vlib_get_buffer (vm, bi1);
            
          ip0 = vlib_buffer_get_current (b0);
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
          icmp0 = (icmp46_header_t *) udp0;

          sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
	  rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index, 
                                   sw_if_index0);

          proto0 = ~0;
          proto0 = (ip0->protocol == IP_PROTOCOL_UDP) 
            ? SNAT_PROTOCOL_UDP : proto0;
          proto0 = (ip0->protocol == IP_PROTOCOL_TCP) 
            ? SNAT_PROTOCOL_TCP : proto0;
          proto0 = (ip0->protocol == IP_PROTOCOL_ICMP) 
            ? SNAT_PROTOCOL_ICMP : proto0;

          if (PREDICT_FALSE (proto0 == ~0))
              goto trace0;

          if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
            {
              next0 = icmp_out2in_slow_path 
                (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, 
                 next0, now, cpu_index);
              goto trace0;
            }

          key0.addr = ip0->dst_address;
          key0.port = udp0->dst_port;
          key0.protocol = proto0;
          key0.fib_index = rx_fib_index0;
          
          kv0.key = key0.as_u64;

          if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0))
            {
              /* Try to match static mapping by external address and port,
                 destination address and port in packet */
              if (snat_static_mapping_match(sm, key0, &sm0, 1))
                {
                  b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
                  goto trace0;
                }

              /* Create session initiated by host from external network */
              s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node,
                                                     cpu_index);
              if (!s0)
                goto trace0;
            }
          else
            s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions,
                                    value0.value);

          old_addr0 = ip0->dst_address.as_u32;
          ip0->dst_address = s0->in2out.addr;
          new_addr0 = ip0->dst_address.as_u32;
          vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;

          sum0 = ip0->checksum;
          sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                 ip4_header_t,
                                 dst_address /* changed member */);
          ip0->checksum = ip_csum_fold (sum0);

          if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP))
            {
              old_port0 = tcp0->ports.dst;
              tcp0->ports.dst = s0->in2out.port;
              new_port0 = tcp0->ports.dst;

              sum0 = tcp0->checksum;
              sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                     ip4_header_t,
                                     dst_address /* changed member */);

              sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                     ip4_header_t /* cheat */,
                                     length /* changed member */);
              tcp0->checksum = ip_csum_fold(sum0);
            }
          else
            {
              old_port0 = udp0->dst_port;
              udp0->dst_port = s0->in2out.port;
              udp0->checksum = 0;
            }

          /* Accounting */
          s0->last_heard = now;
          s0->total_pkts++;
          s0->total_bytes += vlib_buffer_length_in_chain (vm, b0);
          /* Per-user LRU list maintenance for dynamic translation */
          if (!snat_is_session_static (s0))
            {
              clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool,
                                 s0->per_user_index);
              clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool,
                                  s0->per_user_list_head_index,
                                  s0->per_user_index);
            }
        trace0:

          if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) 
                            && (b0->flags & VLIB_BUFFER_IS_TRACED))) 
            {
              snat_out2in_trace_t *t = 
                 vlib_add_trace (vm, node, b0, sizeof (*t));
              t->sw_if_index = sw_if_index0;
              t->next_index = next0;
              t->session_index = ~0;
              if (s0)
                t->session_index = s0 - sm->per_thread_data[cpu_index].sessions;
            }

          pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;


          ip1 = vlib_buffer_get_current (b1);
          udp1 = ip4_next_header (ip1);
          tcp1 = (tcp_header_t *) udp1;
          icmp1 = (icmp46_header_t *) udp1;

          sw_if_index1 = vnet_buffer(b1)->sw_if_index[VLIB_RX];
	  rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index, 
                                   sw_if_index1);

          proto1 = ~0;
          proto1 = (ip1->protocol == IP_PROTOCOL_UDP) 
            ? SNAT_PROTOCOL_UDP : proto1;
          proto1 = (ip1->protocol == IP_PROTOCOL_TCP) 
            ? SNAT_PROTOCOL_TCP : proto1;
          proto1 = (ip1->protocol == IP_PROTOCOL_ICMP) 
            ? SNAT_PROTOCOL_ICMP : proto1;

          if (PREDICT_FALSE (proto1 == ~0))
              goto trace1;

          if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
            {
              next1 = icmp_out2in_slow_path 
                (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node, 
                 next1, now, cpu_index);
              goto trace1;
            }

          key1.addr = ip1->dst_address;
          key1.port = udp1->dst_port;
          key1.protocol = proto1;
          key1.fib_index = rx_fib_index1;
          
          kv1.key = key1.as_u64;

          if (clib_bihash_search_8_8 (&sm->out2in, &kv1, &value1))
            {
              /* Try to match static mapping by external address and port,
                 destination address and port in packet */
              if (snat_static_mapping_match(sm, key1, &sm1, 1))
                {
                  b1->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
                  goto trace1;
                }

              /* Create session initiated by host from external network */
              s1 = create_session_for_static_mapping(sm, b1, sm1, key1, node,
                                                     cpu_index);
              if (!s1)
                goto trace1;
            }
          else
            s1 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions,
                                    value1.value);

          old_addr1 = ip1->dst_address.as_u32;
          ip1->dst_address = s1->in2out.addr;
          new_addr1 = ip1->dst_address.as_u32;
          vnet_buffer(b1)->sw_if_index[VLIB_TX] = s1->in2out.fib_index;

          sum1 = ip1->checksum;
          sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
                                 ip4_header_t,
                                 dst_address /* changed member */);
          ip1->checksum = ip_csum_fold (sum1);

          if (PREDICT_TRUE(proto1 == SNAT_PROTOCOL_TCP))
            {
              old_port1 = tcp1->ports.dst;
              tcp1->ports.dst = s1->in2out.port;
              new_port1 = tcp1->ports.dst;

              sum1 = tcp1->checksum;
              sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
                                     ip4_header_t,
                                     dst_address /* changed member */);

              sum1 = ip_csum_update (sum1, old_port1, new_port1,
                                     ip4_header_t /* cheat */,
                                     length /* changed member */);
              tcp1->checksum = ip_csum_fold(sum1);
            }
          else
            {
              old_port1 = udp1->dst_port;
              udp1->dst_port = s1->in2out.port;
              udp1->checksum = 0;
            }

          /* Accounting */
          s1->last_heard = now;
          s1->total_pkts++;
          s1->total_bytes += vlib_buffer_length_in_chain (vm, b1);
          /* Per-user LRU list maintenance for dynamic translation */
          if (!snat_is_session_static (s1))
            {
              clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool,
                                 s1->per_user_index);
              clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool,
                                  s1->per_user_list_head_index,
                                  s1->per_user_index);
            }
        trace1:

          if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) 
                            && (b1->flags & VLIB_BUFFER_IS_TRACED))) 
            {
              snat_out2in_trace_t *t = 
                 vlib_add_trace (vm, node, b1, sizeof (*t));
              t->sw_if_index = sw_if_index1;
              t->next_index = next1;
              t->session_index = ~0;
              if (s1)
                t->session_index = s1 - sm->per_thread_data[cpu_index].sessions;
            }

          pkts_processed += next1 != SNAT_OUT2IN_NEXT_DROP;

          /* verify speculative enqueues, maybe switch current next frame */
          vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
                                           to_next, n_left_to_next,
                                           bi0, bi1, next0, next1);
        }

      while (n_left_from > 0 && n_left_to_next > 0)
	{
          u32 bi0;
	  vlib_buffer_t * b0;
          u32 next0 = SNAT_OUT2IN_NEXT_LOOKUP;
          u32 sw_if_index0;
          ip4_header_t * ip0;
          ip_csum_t sum0;
          u32 new_addr0, old_addr0;
          u16 new_port0, old_port0;
          udp_header_t * udp0;
          tcp_header_t * tcp0;
          icmp46_header_t * icmp0;
          snat_session_key_t key0, sm0;
          u32 rx_fib_index0;
          u32 proto0;
          snat_session_t * s0 = 0;
          clib_bihash_kv_8_8_t kv0, value0;
          
          /* speculatively enqueue b0 to the current next frame */
	  bi0 = from[0];
	  to_next[0] = bi0;
	  from += 1;
	  to_next += 1;
	  n_left_from -= 1;
	  n_left_to_next -= 1;

	  b0 = vlib_get_buffer (vm, bi0);

          ip0 = vlib_buffer_get_current (b0);
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
          icmp0 = (icmp46_header_t *) udp0;

          sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
	  rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index, 
                                   sw_if_index0);

          proto0 = ~0;
          proto0 = (ip0->protocol == IP_PROTOCOL_UDP) 
            ? SNAT_PROTOCOL_UDP : proto0;
          proto0 = (ip0->protocol == IP_PROTOCOL_TCP) 
            ? SNAT_PROTOCOL_TCP : proto0;
          proto0 = (ip0->protocol == IP_PROTOCOL_ICMP) 
            ? SNAT_PROTOCOL_ICMP : proto0;

          if (PREDICT_FALSE (proto0 == ~0))
              goto trace00;

          if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
            {
              next0 = icmp_out2in_slow_path 
                (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, 
                 next0, now, cpu_index);
              goto trace00;
            }

          key0.addr = ip0->dst_address;
          key0.port = udp0->dst_port;
          key0.protocol = proto0;
          key0.fib_index = rx_fib_index0;
          
          kv0.key = key0.as_u64;

          if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0))
            {
              /* Try to match static mapping by external address and port,
                 destination address and port in packet */
              if (snat_static_mapping_match(sm, key0, &sm0, 1))
                {
                  b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
                  goto trace00;
                }

              /* Create session initiated by host from external network */
              s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node,
                                                     cpu_index);
              if (!s0)
                goto trace00;
            }
          else
            s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions,
                                    value0.value);

          old_addr0 = ip0->dst_address.as_u32;
          ip0->dst_address = s0->in2out.addr;
          new_addr0 = ip0->dst_address.as_u32;
          vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;

          sum0 = ip0->checksum;
          sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                 ip4_header_t,
                                 dst_address /* changed member */);
          ip0->checksum = ip_csum_fold (sum0);

          if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP))
            {
              old_port0 = tcp0->ports.dst;
              tcp0->ports.dst = s0->in2out.port;
              new_port0 = tcp0->ports.dst;

              sum0 = tcp0->checksum;
              sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                     ip4_header_t,
                                     dst_address /* changed member */);

              sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                     ip4_header_t /* cheat */,
                                     length /* changed member */);
              tcp0->checksum = ip_csum_fold(sum0);
            }
          else
            {
              old_port0 = udp0->dst_port;
              udp0->dst_port = s0->in2out.port;
              udp0->checksum = 0;
            }

          /* Accounting */
          s0->last_heard = now;
          s0->total_pkts++;
          s0->total_bytes += vlib_buffer_length_in_chain (vm, b0);
          /* Per-user LRU list maintenance for dynamic translation */
          if (!snat_is_session_static (s0))
            {
              clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool,
                                 s0->per_user_index);
              clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool,
                                  s0->per_user_list_head_index,
                                  s0->per_user_index);
            }
        trace00:

          if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) 
                            && (b0->flags & VLIB_BUFFER_IS_TRACED))) 
            {
              snat_out2in_trace_t *t = 
                 vlib_add_trace (vm, node, b0, sizeof (*t));
              t->sw_if_index = sw_if_index0;
              t->next_index = next0;
              t->session_index = ~0;
              if (s0)
                t->session_index = s0 - sm->per_thread_data[cpu_index].sessions;
            }

          pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;

          /* verify speculative enqueue, maybe switch current next frame */
	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
					   to_next, n_left_to_next,
					   bi0, next0);
	}

      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  vlib_node_increment_counter (vm, snat_out2in_node.index, 
                               SNAT_OUT2IN_ERROR_OUT2IN_PACKETS, 
                               pkts_processed);
  return frame->n_vectors;
}

VLIB_REGISTER_NODE (snat_out2in_node) = {
  .function = snat_out2in_node_fn,
  .name = "snat-out2in",
  .vector_size = sizeof (u32),
  .format_trace = format_snat_out2in_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  
  .n_errors = ARRAY_LEN(snat_out2in_error_strings),
  .error_strings = snat_out2in_error_strings,

  .runtime_data_bytes = sizeof (snat_runtime_t),
  
  .n_next_nodes = SNAT_OUT2IN_N_NEXT,

  /* edit / add dispositions here */
  .next_nodes = {
    [SNAT_OUT2IN_NEXT_DROP] = "error-drop",
    [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
  },
};
VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_node, snat_out2in_node_fn);

static uword
snat_out2in_worker_handoff_fn (vlib_main_t * vm,
                               vlib_node_runtime_t * node,
                               vlib_frame_t * frame)
{
  snat_main_t *sm = &snat_main;
  vlib_thread_main_t *tm = vlib_get_thread_main ();
  u32 n_left_from, *from, *to_next = 0;
  static __thread vlib_frame_queue_elt_t **handoff_queue_elt_by_worker_index;
  static __thread vlib_frame_queue_t **congested_handoff_queue_by_worker_index
    = 0;
  vlib_frame_queue_elt_t *hf = 0;
  vlib_frame_t *f = 0;
  int i;
  u32 n_left_to_next_worker = 0, *to_next_worker = 0;
  u32 next_worker_index = 0;
  u32 current_worker_index = ~0;
  u32 cpu_index = os_get_cpu_number ();

  ASSERT (vec_len (sm->workers));

  if (PREDICT_FALSE (handoff_queue_elt_by_worker_index == 0))
    {
      vec_validate (handoff_queue_elt_by_worker_index, tm->n_vlib_mains - 1);

      vec_validate_init_empty (congested_handoff_queue_by_worker_index,
			       sm->first_worker_index + sm->num_workers - 1,
			       (vlib_frame_queue_t *) (~0));
    }

  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;

  while (n_left_from > 0)
    {
      u32 bi0;
      vlib_buffer_t *b0;
      u32 sw_if_index0;
      u32 rx_fib_index0;
      ip4_header_t * ip0;
      udp_header_t * udp0;
      snat_static_mapping_key_t key0;
      clib_bihash_kv_8_8_t kv0, value0;
      u8 do_handoff;

      bi0 = from[0];
      from += 1;
      n_left_from -= 1;

      b0 = vlib_get_buffer (vm, bi0);

      sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
      rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index0);

      ip0 = vlib_buffer_get_current (b0);
      udp0 = ip4_next_header (ip0);

      key0.addr = ip0->dst_address;
      key0.port = udp0->dst_port;
      key0.fib_index = rx_fib_index0;

      if (PREDICT_FALSE(ip0->protocol == IP_PROTOCOL_ICMP))
        {
          icmp46_header_t * icmp0 = (icmp46_header_t *) udp0;
          icmp_echo_header_t *echo0 = (icmp_echo_header_t *)(icmp0+1);
          key0.port = echo0->identifier;
        }

      kv0.key = key0.as_u64;

      /* Ever heard of of the "user" before? */
      if (clib_bihash_search_8_8 (&sm->worker_by_out, &kv0, &value0))
        {
          key0.port = 0;
          kv0.key = key0.as_u64;

          if (clib_bihash_search_8_8 (&sm->worker_by_out, &kv0, &value0))
            {
              /* No, assign next available worker (RR) */
              next_worker_index = sm->first_worker_index;
              if (vec_len (sm->workers))
                {
                  next_worker_index += 
                    sm->workers[sm->next_worker++ % _vec_len (sm->workers)];
                }
            }
          else
            {
              /* Static mapping without port */
              next_worker_index = value0.value;
            }

          /* Add to translated packets worker lookup */
          kv0.value = next_worker_index;
          clib_bihash_add_del_8_8 (&sm->worker_by_out, &kv0, 1);
        }
      else
        next_worker_index = value0.value;

      if (PREDICT_FALSE (next_worker_index != cpu_index))
        {
          do_handoff = 1;

          if (next_worker_index != current_worker_index)
            {
              if (hf)
                hf->n_vectors = VLIB_FRAME_SIZE - n_left_to_next_worker;

              hf = vlib_get_worker_handoff_queue_elt (sm->fq_out2in_index,
                                                      next_worker_index,
                                                      handoff_queue_elt_by_worker_index);

              n_left_to_next_worker = VLIB_FRAME_SIZE - hf->n_vectors;
              to_next_worker = &hf->buffer_index[hf->n_vectors];
              current_worker_index = next_worker_index;
            }

          /* enqueue to correct worker thread */
          to_next_worker[0] = bi0;
          to_next_worker++;
          n_left_to_next_worker--;

          if (n_left_to_next_worker == 0)
            {
              hf->n_vectors = VLIB_FRAME_SIZE;
              vlib_put_frame_queue_elt (hf);
              current_worker_index = ~0;
              handoff_queue_elt_by_worker_index[next_worker_index] = 0;
              hf = 0;
            }
        }
      else
        {
          do_handoff = 0;
          /* if this is 1st frame */
          if (!f)
            {
              f = vlib_get_frame_to_node (vm, snat_out2in_node.index);
              to_next = vlib_frame_vector_args (f);
            }

          to_next[0] = bi0;
          to_next += 1;
          f->n_vectors++;
        }

      if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
			 && (b0->flags & VLIB_BUFFER_IS_TRACED)))
	{
          snat_out2in_worker_handoff_trace_t *t =
            vlib_add_trace (vm, node, b0, sizeof (*t));
          t->next_worker_index = next_worker_index;
          t->do_handoff = do_handoff;
        }
    }

  if (f)
    vlib_put_frame_to_node (vm, snat_out2in_node.index, f);

  if (hf)
    hf->n_vectors = VLIB_FRAME_SIZE - n_left_to_next_worker;

  /* Ship frames to the worker nodes */
  for (i = 0; i < vec_len (handoff_queue_elt_by_worker_index); i++)
    {
      if (handoff_queue_elt_by_worker_index[i])
	{
	  hf = handoff_queue_elt_by_worker_index[i];
	  /*
	   * It works better to let the handoff node
	   * rate-adapt, always ship the handoff queue element.
	   */
	  if (1 || hf->n_vectors == hf->last_n_vectors)
	    {
	      vlib_put_frame_queue_elt (hf);
	      handoff_queue_elt_by_worker_index[i] = 0;
	    }
	  else
	    hf->last_n_vectors = hf->n_vectors;
	}
      congested_handoff_queue_by_worker_index[i] =
	(vlib_frame_queue_t *) (~0);
    }
  hf = 0;
  current_worker_index = ~0;
  return frame->n_vectors;
}

VLIB_REGISTER_NODE (snat_out2in_worker_handoff_node) = {
  .function = snat_out2in_worker_handoff_fn,
  .name = "snat-out2in-worker-handoff",
  .vector_size = sizeof (u32),
  .format_trace = format_snat_out2in_worker_handoff_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  
  .n_next_nodes = 1,

  .next_nodes = {
    [0] = "error-drop",
  },
};

VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_worker_handoff_node, snat_out2in_worker_handoff_fn);

static inline u32 icmp_out2in_fast (snat_main_t *sm,
                                    vlib_buffer_t * b0,
                                    ip4_header_t * ip0,
                                    icmp46_header_t * icmp0,
                                    u32 sw_if_index0,
                                    vlib_node_runtime_t * node,
                                    u32 next0,
                                    u32 rx_fib_index0)
{
  snat_session_key_t key0, sm0;
  icmp_echo_header_t *echo0;
  u32 new_addr0, old_addr0;
  u16 old_id0, new_id0;
  ip_csum_t sum0;
  snat_runtime_t * rt = (snat_runtime_t *)node->runtime_data;

  echo0 = (icmp_echo_header_t *)(icmp0+1);

  key0.addr = ip0->dst_address;
  key0.port = echo0->identifier;
  key0.fib_index = rx_fib_index0;

  if (snat_static_mapping_match(sm, key0, &sm0, 1))
    {
      ip4_address_t * first_int_addr;

      if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0))
        {
          first_int_addr =
            ip4_interface_first_address (sm->ip4_main, sw_if_index0,
                                         0 /* just want the address */);
          rt->cached_sw_if_index = sw_if_index0;
          if (first_int_addr)
            rt->cached_ip4_address = first_int_addr->as_u32;
          else
            rt->cached_ip4_address = 0;
        }

      /* Don't NAT packet aimed at the intfc address */
      if (PREDICT_FALSE(ip0->dst_address.as_u32 ==
                        rt->cached_ip4_address))
        return next0;

      b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
      return SNAT_OUT2IN_NEXT_DROP;
    }

  new_addr0 = sm0.addr.as_u32;
  new_id0 = sm0.port;
  vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm0.fib_index;

  old_addr0 = ip0->dst_address.as_u32;
  ip0->dst_address.as_u32 = new_addr0;

  sum0 = ip0->checksum;
  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                         ip4_header_t,
                         dst_address /* changed member */);
  ip0->checksum = ip_csum_fold (sum0);

  if (PREDICT_FALSE(new_id0 != echo0->identifier))
    {
      old_id0 = echo0->identifier;
      echo0->identifier = new_id0;

      sum0 = icmp0->checksum;
      sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
                             identifier);
      icmp0->checksum = ip_csum_fold (sum0);
    }

  return next0;
}

static uword
snat_out2in_fast_node_fn (vlib_main_t * vm,
	        	  vlib_node_runtime_t * node,
		          vlib_frame_t * frame)
{
  u32 n_left_from, * from, * to_next;
  snat_out2in_next_t next_index;
  u32 pkts_processed = 0;
  snat_main_t * sm = &snat_main;

  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;

  while (n_left_from > 0)
    {
      u32 n_left_to_next;

      vlib_get_next_frame (vm, node, next_index,
			   to_next, n_left_to_next);

      while (n_left_from > 0 && n_left_to_next > 0)
	{
          u32 bi0;
	  vlib_buffer_t * b0;
          u32 next0 = SNAT_OUT2IN_NEXT_DROP;
          u32 sw_if_index0;
          ip4_header_t * ip0;
          ip_csum_t sum0;
          u32 new_addr0, old_addr0;
          u16 new_port0, old_port0;
          udp_header_t * udp0;
          tcp_header_t * tcp0;
          icmp46_header_t * icmp0;
          snat_session_key_t key0, sm0;
          u32 proto0;
          u32 rx_fib_index0;

          /* speculatively enqueue b0 to the current next frame */
	  bi0 = from[0];
	  to_next[0] = bi0;
	  from += 1;
	  to_next += 1;
	  n_left_from -= 1;
	  n_left_to_next -= 1;

	  b0 = vlib_get_buffer (vm, bi0);

          ip0 = vlib_buffer_get_current (b0);
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
          icmp0 = (icmp46_header_t *) udp0;

          sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
	  rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index0);

	  vnet_feature_next (sw_if_index0, &next0, b0);

          proto0 = ~0;
          proto0 = (ip0->protocol == IP_PROTOCOL_UDP)
            ? SNAT_PROTOCOL_UDP : proto0;
          proto0 = (ip0->protocol == IP_PROTOCOL_TCP)
            ? SNAT_PROTOCOL_TCP : proto0;
          proto0 = (ip0->protocol == IP_PROTOCOL_ICMP)
            ? SNAT_PROTOCOL_ICMP : proto0;

          if (PREDICT_FALSE (proto0 == ~0))
              goto trace00;

          if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
            {
              next0 = icmp_out2in_fast
                (sm, b0, ip0, icmp0, sw_if_index0, node, next0, rx_fib_index0);
              goto trace00;
            }

          key0.addr = ip0->dst_address;
          key0.port = udp0->dst_port;
          key0.fib_index = rx_fib_index0;

          if (snat_static_mapping_match(sm, key0, &sm0, 1))
            {
              b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION];
              goto trace00;
            }

          new_addr0 = sm0.addr.as_u32;
          new_port0 = sm0.port;
          vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
          old_addr0 = ip0->dst_address.as_u32;
          ip0->dst_address.as_u32 = new_addr0;

          sum0 = ip0->checksum;
          sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                 ip4_header_t,
                                 dst_address /* changed member */);
          ip0->checksum = ip_csum_fold (sum0);

          if (PREDICT_FALSE(new_port0 != udp0->dst_port))
            {
               if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP))
                {
                  old_port0 = tcp0->ports.dst;
                  tcp0->ports.dst = new_port0;

                  sum0 = tcp0->checksum;
                  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                         ip4_header_t,
                                         dst_address /* changed member */);

                  sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                         ip4_header_t /* cheat */,
                                         length /* changed member */);
                  tcp0->checksum = ip_csum_fold(sum0);
                }
              else
                {
                  old_port0 = udp0->dst_port;
                  udp0->dst_port = new_port0;
                  udp0->checksum = 0;
                }
            }
          else
            {
              if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP))
                {
                  sum0 = tcp0->checksum;
                  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                         ip4_header_t,
                                         dst_address /* changed member */);

                  tcp0->checksum = ip_csum_fold(sum0);
                }
            }

        trace00:

          if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE)
                            && (b0->flags & VLIB_BUFFER_IS_TRACED)))
            {
              snat_out2in_trace_t *t =
                 vlib_add_trace (vm, node, b0, sizeof (*t));
              t->sw_if_index = sw_if_index0;
              t->next_index = next0;
            }

          pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP;

          /* verify speculative enqueue, maybe switch current next frame */
	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
					   to_next, n_left_to_next,
					   bi0, next0);
	}

      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  vlib_node_increment_counter (vm, snat_out2in_fast_node.index,
                               SNAT_OUT2IN_ERROR_OUT2IN_PACKETS,
                               pkts_processed);
  return frame->n_vectors;
}

VLIB_REGISTER_NODE (snat_out2in_fast_node) = {
  .function = snat_out2in_fast_node_fn,
  .name = "snat-out2in-fast",
  .vector_size = sizeof (u32),
  .format_trace = format_snat_out2in_fast_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  
  .n_errors = ARRAY_LEN(snat_out2in_error_strings),
  .error_strings = snat_out2in_error_strings,

  .runtime_data_bytes = sizeof (snat_runtime_t),
  
  .n_next_nodes = SNAT_OUT2IN_N_NEXT,

  /* edit / add dispositions here */
  .next_nodes = {
    [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
    [SNAT_OUT2IN_NEXT_DROP] = "error-drop",
  },
};
VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_fast_node, snat_out2in_fast_node_fn);