src/plugins/nat/in2out.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 inside to outside 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/ethernet/ethernet.h>
  26 #include <vnet/fib/ip4_fib.h>
  27 #include <vnet/udp/udp.h>
  28 #include <nat/nat.h>
  29 #include <nat/nat_ipfix_logging.h>
  30 #include <nat/nat_inlines.h>
  31 #include <nat/nat44/inlines.h>
  32 #include <nat/nat_syslog.h>
  33 #include <nat/nat_ha.h>
  34
  35 #include <vppinfra/hash.h>
  36 #include <vppinfra/error.h>
  37 #include <vppinfra/elog.h>
  38 #include <nat/lib/nat_inlines.h>
  39
  40 typedef struct
  41 {
  42   u32 sw_if_index;
  43   u32 next_index;
  44   u32 session_index;
  45   u32 is_slow_path;
  46   u32 is_hairpinning;
  47 } snat_in2out_trace_t;
  48
  49 /* packet trace format function */
  50 static u8 *
  51 format_snat_in2out_trace (u8 * s, va_list * args)
  52 {
  53   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  54   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  55   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  56   char *tag;
  57
  58   tag = t->is_slow_path ? "NAT44_IN2OUT_SLOW_PATH" : "NAT44_IN2OUT_FAST_PATH";
  59
  60   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  61               t->sw_if_index, t->next_index, t->session_index);
  62   if (t->is_hairpinning)
  63     {
  64       s = format (s, ", with-hairpinning");
  65     }
  66
  67   return s;
  68 }
  69
  70 static u8 *
  71 format_snat_in2out_fast_trace (u8 * s, va_list * args)
  72 {
  73   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  74   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  75   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  76
  77   s = format (s, "NAT44_IN2OUT_FAST: sw_if_index %d, next index %d",
  78               t->sw_if_index, t->next_index);
  79
  80   return s;
  81 }
  82
  83 #define foreach_snat_in2out_error                       \
  84 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
  85 _(IN2OUT_PACKETS, "good in2out packets processed")      \
  86 _(OUT_OF_PORTS, "out of ports")                         \
  87 _(BAD_OUTSIDE_FIB, "outside VRF ID not found")          \
  88 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  89 _(NO_TRANSLATION, "no translation")                     \
  90 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
  91 _(DROP_FRAGMENT, "drop fragment")                       \
  92 _(TCP_PACKETS, "TCP packets")                           \
  93 _(UDP_PACKETS, "UDP packets")                           \
  94 _(ICMP_PACKETS, "ICMP packets")                         \
  95 _(OTHER_PACKETS, "other protocol packets")              \
  96 _(FRAGMENTS, "fragments")                               \
  97 _(CACHED_FRAGMENTS, "cached fragments")                 \
  98 _(PROCESSED_FRAGMENTS, "processed fragments")
  99
 100 typedef enum
 101 {
 102 #define _(sym,str) SNAT_IN2OUT_ERROR_##sym,
 103   foreach_snat_in2out_error
 104 #undef _
 105     SNAT_IN2OUT_N_ERROR,
 106 } snat_in2out_error_t;
 107
 108 static char *snat_in2out_error_strings[] = {
 109 #define _(sym,string) string,
 110   foreach_snat_in2out_error
 111 #undef _
 112 };
 113
 114 typedef enum
 115 {
 116   SNAT_IN2OUT_NEXT_LOOKUP,
 117   SNAT_IN2OUT_NEXT_DROP,
 118   SNAT_IN2OUT_NEXT_ICMP_ERROR,
 119   SNAT_IN2OUT_NEXT_SLOW_PATH,
 120   SNAT_IN2OUT_N_NEXT,
 121 } snat_in2out_next_t;
 122
 123 static inline int
 124 snat_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 125                     u32 sw_if_index0, ip4_header_t * ip0, u32 proto0,
 126                     u32 rx_fib_index0, u32 thread_index)
 127 {
 128   udp_header_t *udp0 = ip4_next_header (ip0);
 129   snat_session_key_t key0, sm0;
 130   clib_bihash_kv_8_8_t kv0, value0;
 131
 132   key0.addr = ip0->dst_address;
 133   key0.port = udp0->dst_port;
 134   key0.protocol = proto0;
 135   key0.fib_index = sm->outside_fib_index;
 136   kv0.key = key0.as_u64;
 137
 138   /* NAT packet aimed at external address if */
 139   /* has active sessions */
 140   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
 141                               &value0))
 142     {
 143       /* or is static mappings */
 144       if (!snat_static_mapping_match (sm, key0, &sm0, 1, 0, 0, 0, 0, 0))
 145         return 0;
 146     }
 147   else
 148     return 0;
 149
 150   if (sm->forwarding_enabled)
 151     return 1;
 152
 153   return snat_not_translate_fast (sm, node, sw_if_index0, ip0, proto0,
 154                                   rx_fib_index0);
 155 }
 156
 157 static inline int
 158 nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
 159                                   u32 proto0, u16 src_port, u16 dst_port,
 160                                   u32 thread_index, u32 sw_if_index)
 161 {
 162   snat_session_key_t key0;
 163   clib_bihash_kv_8_8_t kv0, value0;
 164   snat_interface_t *i;
 165
 166   /* src NAT check */
 167   key0.addr = ip0->src_address;
 168   key0.port = src_port;
 169   key0.protocol = proto0;
 170   key0.fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 171   kv0.key = key0.as_u64;
 172
 173   if (!clib_bihash_search_8_8
 174       (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
 175     return 1;
 176
 177   /* dst NAT check */
 178   key0.addr = ip0->dst_address;
 179   key0.port = dst_port;
 180   key0.protocol = proto0;
 181   kv0.key = key0.as_u64;
 182   if (!clib_bihash_search_8_8
 183       (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
 184     {
 185       /* hairpinning */
 186     /* *INDENT-OFF* */
 187     pool_foreach (i, sm->output_feature_interfaces,
 188     ({
 189       if ((nat_interface_is_inside(i)) && (sw_if_index == i->sw_if_index))
 190         return 0;
 191     }));
 192     /* *INDENT-ON* */
 193       return 1;
 194     }
 195
 196   return 0;
 197 }
 198
 199 #ifndef CLIB_MARCH_VARIANT
 200 int
 201 nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
 202 {
 203   snat_main_t *sm = &snat_main;
 204   nat44_is_idle_session_ctx_t *ctx = arg;
 205   snat_session_t *s;
 206   u64 sess_timeout_time;
 207   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 208                                                        ctx->thread_index);
 209   clib_bihash_kv_8_8_t s_kv;
 210
 211   s = pool_elt_at_index (tsm->sessions, kv->value);
 212   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 213   if (ctx->now >= sess_timeout_time)
 214     {
 215       s_kv.key = s->out2in.as_u64;
 216       if (clib_bihash_add_del_8_8 (&tsm->out2in, &s_kv, 0))
 217         nat_elog_warn ("out2in key del failed");
 218
 219       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 220                                            s->in2out.addr.as_u32,
 221                                            s->out2in.addr.as_u32,
 222                                            s->in2out.protocol,
 223                                            s->in2out.port,
 224                                            s->out2in.port,
 225                                            s->in2out.fib_index);
 226
 227       nat_syslog_nat44_apmdel (s->user_index, s->in2out.fib_index,
 228                                &s->in2out.addr, s->in2out.port,
 229                                &s->out2in.addr, s->out2in.port,
 230                                s->in2out.protocol);
 231
 232       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 233                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 234                    ctx->thread_index);
 235
 236       if (!snat_is_session_static (s))
 237         snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 238                                             &s->out2in);
 239
 240       nat44_delete_session (sm, s, ctx->thread_index);
 241       return 1;
 242     }
 243
 244   return 0;
 245 }
 246 #endif
 247
 248 static u32
 249 slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 250            ip4_header_t * ip0,
 251            u32 rx_fib_index0,
 252            snat_session_key_t * key0,
 253            snat_session_t ** sessionp,
 254            vlib_node_runtime_t * node, u32 next0, u32 thread_index, f64 now)
 255 {
 256   snat_user_t *u;
 257   snat_session_t *s = 0;
 258   clib_bihash_kv_8_8_t kv0;
 259   snat_session_key_t key1;
 260   u8 is_sm = 0;
 261   nat_outside_fib_t *outside_fib;
 262   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 263   u8 identity_nat;
 264   fib_prefix_t pfx = {
 265     .fp_proto = FIB_PROTOCOL_IP4,
 266     .fp_len = 32,
 267     .fp_addr = {
 268                 .ip4.as_u32 = ip0->dst_address.as_u32,
 269                 },
 270   };
 271   nat44_is_idle_session_ctx_t ctx0;
 272
 273   if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 274     {
 275       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_SESSIONS_EXCEEDED];
 276       nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 277       nat_elog_notice ("maximum sessions exceeded");
 278       return SNAT_IN2OUT_NEXT_DROP;
 279     }
 280
 281   key1.protocol = key0->protocol;
 282
 283   /* First try to match static mapping by local address and port */
 284   if (snat_static_mapping_match
 285       (sm, *key0, &key1, 0, 0, 0, 0, 0, &identity_nat))
 286     {
 287       /* Try to create dynamic translation */
 288       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index0,
 289                                                thread_index, &key1,
 290                                                sm->port_per_thread,
 291                                                sm->per_thread_data
 292                                                [thread_index].snat_thread_index))
 293         {
 294           b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
 295           return SNAT_IN2OUT_NEXT_DROP;
 296         }
 297     }
 298   else
 299     {
 300       if (PREDICT_FALSE (identity_nat))
 301         {
 302           *sessionp = s;
 303           return next0;
 304         }
 305
 306       is_sm = 1;
 307     }
 308
 309   u = nat_user_get_or_create (sm, &ip0->src_address, rx_fib_index0,
 310                               thread_index);
 311   if (!u)
 312     {
 313       nat_elog_warn ("create NAT user failed");
 314       return SNAT_IN2OUT_NEXT_DROP;
 315     }
 316
 317   s = nat_session_alloc_or_recycle (sm, u, thread_index, now);
 318   if (!s)
 319     {
 320       nat44_delete_user_with_no_session (sm, u, thread_index);
 321       nat_elog_warn ("create NAT session failed");
 322       return SNAT_IN2OUT_NEXT_DROP;
 323     }
 324
 325   if (is_sm)
 326     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 327   user_session_increment (sm, u, is_sm);
 328   s->in2out = *key0;
 329   s->out2in = key1;
 330   s->out2in.protocol = key0->protocol;
 331   s->out2in.fib_index = sm->outside_fib_index;
 332   switch (vec_len (sm->outside_fibs))
 333     {
 334     case 0:
 335       s->out2in.fib_index = sm->outside_fib_index;
 336       break;
 337     case 1:
 338       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 339       break;
 340     default:
 341       /* *INDENT-OFF* */
 342       vec_foreach (outside_fib, sm->outside_fibs)
 343         {
 344           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 345           if (FIB_NODE_INDEX_INVALID != fei)
 346             {
 347               if (fib_entry_get_resolving_interface (fei) != ~0)
 348                 {
 349                   s->out2in.fib_index = outside_fib->fib_index;
 350                   break;
 351                 }
 352             }
 353         }
 354       /* *INDENT-ON* */
 355       break;
 356     }
 357   s->ext_host_addr.as_u32 = ip0->dst_address.as_u32;
 358   s->ext_host_port = vnet_buffer (b0)->ip.reass.l4_dst_port;
 359   *sessionp = s;
 360
 361   /* Add to translation hashes */
 362   ctx0.now = now;
 363   ctx0.thread_index = thread_index;
 364   kv0.key = s->in2out.as_u64;
 365   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 366   if (clib_bihash_add_or_overwrite_stale_8_8
 367       (&sm->per_thread_data[thread_index].in2out, &kv0,
 368        nat44_i2o_is_idle_session_cb, &ctx0))
 369     nat_elog_notice ("in2out key add failed");
 370
 371   kv0.key = s->out2in.as_u64;
 372   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 373
 374   if (clib_bihash_add_or_overwrite_stale_8_8
 375       (&sm->per_thread_data[thread_index].out2in, &kv0,
 376        nat44_o2i_is_idle_session_cb, &ctx0))
 377     nat_elog_notice ("out2in key add failed");
 378
 379   /* log NAT event */
 380   snat_ipfix_logging_nat44_ses_create (thread_index,
 381                                        s->in2out.addr.as_u32,
 382                                        s->out2in.addr.as_u32,
 383                                        s->in2out.protocol,
 384                                        s->in2out.port,
 385                                        s->out2in.port, s->in2out.fib_index);
 386
 387   nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
 388                            &s->in2out.addr, s->in2out.port, &s->out2in.addr,
 389                            s->out2in.port, s->in2out.protocol);
 390
 391   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 392                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 393                &s->ext_host_nat_addr, s->ext_host_nat_port,
 394                s->in2out.protocol, s->in2out.fib_index, s->flags,
 395                thread_index, 0);
 396
 397   return next0;
 398 }
 399
 400 #ifndef CLIB_MARCH_VARIANT
 401 static_always_inline
 402   snat_in2out_error_t icmp_get_key (vlib_buffer_t * b, ip4_header_t * ip0,
 403                                     snat_session_key_t * p_key0)
 404 {
 405   icmp46_header_t *icmp0;
 406   snat_session_key_t key0;
 407   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 408   ip4_header_t *inner_ip0 = 0;
 409   void *l4_header = 0;
 410   icmp46_header_t *inner_icmp0;
 411
 412   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 413   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 414
 415   if (!icmp_type_is_error_message
 416       (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
 417     {
 418       key0.protocol = NAT_PROTOCOL_ICMP;
 419       key0.addr = ip0->src_address;
 420       key0.port = vnet_buffer (b)->ip.reass.l4_src_port;
 421     }
 422   else
 423     {
 424       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 425       l4_header = ip4_next_header (inner_ip0);
 426       key0.protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
 427       key0.addr = inner_ip0->dst_address;
 428       switch (key0.protocol)
 429         {
 430         case NAT_PROTOCOL_ICMP:
 431           inner_icmp0 = (icmp46_header_t *) l4_header;
 432           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 433           key0.port = inner_echo0->identifier;
 434           break;
 435         case NAT_PROTOCOL_UDP:
 436         case NAT_PROTOCOL_TCP:
 437           key0.port = ((tcp_udp_header_t *) l4_header)->dst_port;
 438           break;
 439         default:
 440           return SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL;
 441         }
 442     }
 443   *p_key0 = key0;
 444   return -1;                    /* success */
 445 }
 446
 447 /**
 448  * Get address and port values to be used for ICMP packet translation
 449  * and create session if needed
 450  *
 451  * @param[in,out] sm             NAT main
 452  * @param[in,out] node           NAT node runtime
 453  * @param[in] thread_index       thread index
 454  * @param[in,out] b0             buffer containing packet to be translated
 455  * @param[in,out] ip0            ip header
 456  * @param[out] p_proto           protocol used for matching
 457  * @param[out] p_value           address and port after NAT translation
 458  * @param[out] p_dont_translate  if packet should not be translated
 459  * @param d                      optional parameter
 460  * @param e                      optional parameter
 461  */
 462 u32
 463 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
 464                         u32 thread_index, vlib_buffer_t * b0,
 465                         ip4_header_t * ip0, u8 * p_proto,
 466                         snat_session_key_t * p_value,
 467                         u8 * p_dont_translate, void *d, void *e)
 468 {
 469   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 470   u32 sw_if_index0;
 471   u32 rx_fib_index0;
 472   snat_session_key_t key0;
 473   snat_session_t *s0 = 0;
 474   u8 dont_translate = 0;
 475   clib_bihash_kv_8_8_t kv0, value0;
 476   u32 next0 = ~0;
 477   int err;
 478   vlib_main_t *vm = vlib_get_main ();
 479
 480   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 481   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 482
 483   err = icmp_get_key (b0, ip0, &key0);
 484   if (err != -1)
 485     {
 486       b0->error = node->errors[err];
 487       next0 = SNAT_IN2OUT_NEXT_DROP;
 488       goto out;
 489     }
 490   key0.fib_index = rx_fib_index0;
 491
 492   kv0.key = key0.as_u64;
 493
 494   if (clib_bihash_search_8_8 (&tsm->in2out, &kv0, &value0))
 495     {
 496       if (vnet_buffer (b0)->sw_if_index[VLIB_TX] != ~0)
 497         {
 498           if (PREDICT_FALSE (nat_not_translate_output_feature (sm, ip0,
 499                                                                key0.protocol,
 500                                                                key0.port,
 501                                                                key0.port,
 502                                                                thread_index,
 503                                                                sw_if_index0)))
 504             {
 505               dont_translate = 1;
 506               goto out;
 507             }
 508         }
 509       else
 510         {
 511           if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
 512                                                  ip0, NAT_PROTOCOL_ICMP,
 513                                                  rx_fib_index0,
 514                                                  thread_index)))
 515             {
 516               dont_translate = 1;
 517               goto out;
 518             }
 519         }
 520
 521       if (PREDICT_FALSE
 522           (icmp_type_is_error_message
 523            (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags)))
 524         {
 525           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 526           next0 = SNAT_IN2OUT_NEXT_DROP;
 527           goto out;
 528         }
 529
 530       next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0,
 531                          thread_index, vlib_time_now (vm));
 532
 533       if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
 534         goto out;
 535
 536       if (!s0)
 537         {
 538           dont_translate = 1;
 539           goto out;
 540         }
 541     }
 542   else
 543     {
 544       if (PREDICT_FALSE
 545           (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 546            ICMP4_echo_request
 547            && vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 548            ICMP4_echo_reply
 549            && !icmp_type_is_error_message (vnet_buffer (b0)->ip.
 550                                            reass.icmp_type_or_tcp_flags)))
 551         {
 552           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 553           next0 = SNAT_IN2OUT_NEXT_DROP;
 554           goto out;
 555         }
 556
 557       s0 = pool_elt_at_index (tsm->sessions, value0.value);
 558     }
 559
 560 out:
 561   *p_proto = key0.protocol;
 562   if (s0)
 563     *p_value = s0->out2in;
 564   *p_dont_translate = dont_translate;
 565   if (d)
 566     *(snat_session_t **) d = s0;
 567   return next0;
 568 }
 569 #endif
 570
 571 #ifndef CLIB_MARCH_VARIANT
 572 /**
 573  * Get address and port values to be used for ICMP packet translation
 574  *
 575  * @param[in] sm                 NAT main
 576  * @param[in,out] node           NAT node runtime
 577  * @param[in] thread_index       thread index
 578  * @param[in,out] b0             buffer containing packet to be translated
 579  * @param[in,out] ip0            ip header
 580  * @param[out] p_proto           protocol used for matching
 581  * @param[out] p_value           address and port after NAT translation
 582  * @param[out] p_dont_translate  if packet should not be translated
 583  * @param d                      optional parameter
 584  * @param e                      optional parameter
 585  */
 586 u32
 587 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
 588                         u32 thread_index, vlib_buffer_t * b0,
 589                         ip4_header_t * ip0, u8 * p_proto,
 590                         snat_session_key_t * p_value,
 591                         u8 * p_dont_translate, void *d, void *e)
 592 {
 593   u32 sw_if_index0;
 594   u32 rx_fib_index0;
 595   snat_session_key_t key0;
 596   snat_session_key_t sm0;
 597   u8 dont_translate = 0;
 598   u8 is_addr_only;
 599   u32 next0 = ~0;
 600   int err;
 601
 602   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 603   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 604
 605   err = icmp_get_key (b0, ip0, &key0);
 606   if (err != -1)
 607     {
 608       b0->error = node->errors[err];
 609       next0 = SNAT_IN2OUT_NEXT_DROP;
 610       goto out2;
 611     }
 612   key0.fib_index = rx_fib_index0;
 613
 614   if (snat_static_mapping_match
 615       (sm, key0, &sm0, 0, &is_addr_only, 0, 0, 0, 0))
 616     {
 617       if (PREDICT_FALSE (snat_not_translate_fast (sm, node, sw_if_index0, ip0,
 618                                                   IP_PROTOCOL_ICMP,
 619                                                   rx_fib_index0)))
 620         {
 621           dont_translate = 1;
 622           goto out;
 623         }
 624
 625       if (icmp_type_is_error_message
 626           (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags))
 627         {
 628           next0 = SNAT_IN2OUT_NEXT_DROP;
 629           goto out;
 630         }
 631
 632       b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
 633       next0 = SNAT_IN2OUT_NEXT_DROP;
 634       goto out;
 635     }
 636
 637   if (PREDICT_FALSE
 638       (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_request
 639        && (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 640            ICMP4_echo_reply || !is_addr_only)
 641        && !icmp_type_is_error_message (vnet_buffer (b0)->ip.
 642                                        reass.icmp_type_or_tcp_flags)))
 643     {
 644       b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 645       next0 = SNAT_IN2OUT_NEXT_DROP;
 646       goto out;
 647     }
 648
 649 out:
 650   *p_value = sm0;
 651 out2:
 652   *p_proto = key0.protocol;
 653   *p_dont_translate = dont_translate;
 654   return next0;
 655 }
 656 #endif
 657
 658 #ifndef CLIB_MARCH_VARIANT
 659 u32
 660 icmp_in2out (snat_main_t * sm,
 661              vlib_buffer_t * b0,
 662              ip4_header_t * ip0,
 663              icmp46_header_t * icmp0,
 664              u32 sw_if_index0,
 665              u32 rx_fib_index0,
 666              vlib_node_runtime_t * node,
 667              u32 next0, u32 thread_index, void *d, void *e)
 668 {
 669   vlib_main_t *vm = vlib_get_main ();
 670   snat_session_key_t sm0;
 671   u8 protocol;
 672   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 673   ip4_header_t *inner_ip0;
 674   void *l4_header = 0;
 675   icmp46_header_t *inner_icmp0;
 676   u8 dont_translate;
 677   u32 new_addr0, old_addr0;
 678   u16 old_id0, new_id0;
 679   u16 old_checksum0, new_checksum0;
 680   ip_csum_t sum0;
 681   u16 checksum0;
 682   u32 next0_tmp;
 683
 684   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 685
 686   next0_tmp = sm->icmp_match_in2out_cb (sm, node, thread_index, b0, ip0,
 687                                         &protocol, &sm0, &dont_translate, d,
 688                                         e);
 689   if (next0_tmp != ~0)
 690     next0 = next0_tmp;
 691   if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
 692     goto out;
 693
 694   if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
 695     {
 696       sum0 =
 697         ip_incremental_checksum_buffer (vm, b0,
 698                                         (u8 *) icmp0 -
 699                                         (u8 *) vlib_buffer_get_current (b0),
 700                                         ntohs (ip0->length) -
 701                                         ip4_header_bytes (ip0), 0);
 702       checksum0 = ~ip_csum_fold (sum0);
 703       if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff))
 704         {
 705           next0 = SNAT_IN2OUT_NEXT_DROP;
 706           goto out;
 707         }
 708     }
 709
 710   old_addr0 = ip0->src_address.as_u32;
 711   new_addr0 = ip0->src_address.as_u32 = sm0.addr.as_u32;
 712
 713   sum0 = ip0->checksum;
 714   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 715                          src_address /* changed member */ );
 716   ip0->checksum = ip_csum_fold (sum0);
 717
 718   if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 719     {
 720       if (icmp0->checksum == 0)
 721         icmp0->checksum = 0xffff;
 722
 723       if (!icmp_type_is_error_message (icmp0->type))
 724         {
 725           new_id0 = sm0.port;
 726           if (PREDICT_FALSE (new_id0 != echo0->identifier))
 727             {
 728               old_id0 = echo0->identifier;
 729               new_id0 = sm0.port;
 730               echo0->identifier = new_id0;
 731
 732               sum0 = icmp0->checksum;
 733               sum0 =
 734                 ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 735                                 identifier);
 736               icmp0->checksum = ip_csum_fold (sum0);
 737             }
 738         }
 739       else
 740         {
 741           inner_ip0 = (ip4_header_t *) (echo0 + 1);
 742           l4_header = ip4_next_header (inner_ip0);
 743
 744           if (!ip4_header_checksum_is_valid (inner_ip0))
 745             {
 746               next0 = SNAT_IN2OUT_NEXT_DROP;
 747               goto out;
 748             }
 749
 750           /* update inner destination IP address */
 751           old_addr0 = inner_ip0->dst_address.as_u32;
 752           inner_ip0->dst_address = sm0.addr;
 753           new_addr0 = inner_ip0->dst_address.as_u32;
 754           sum0 = icmp0->checksum;
 755           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 756                                  dst_address /* changed member */ );
 757           icmp0->checksum = ip_csum_fold (sum0);
 758
 759           /* update inner IP header checksum */
 760           old_checksum0 = inner_ip0->checksum;
 761           sum0 = inner_ip0->checksum;
 762           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 763                                  dst_address /* changed member */ );
 764           inner_ip0->checksum = ip_csum_fold (sum0);
 765           new_checksum0 = inner_ip0->checksum;
 766           sum0 = icmp0->checksum;
 767           sum0 =
 768             ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
 769                             checksum);
 770           icmp0->checksum = ip_csum_fold (sum0);
 771
 772           switch (protocol)
 773             {
 774             case NAT_PROTOCOL_ICMP:
 775               inner_icmp0 = (icmp46_header_t *) l4_header;
 776               inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 777
 778               old_id0 = inner_echo0->identifier;
 779               new_id0 = sm0.port;
 780               inner_echo0->identifier = new_id0;
 781
 782               sum0 = icmp0->checksum;
 783               sum0 =
 784                 ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 785                                 identifier);
 786               icmp0->checksum = ip_csum_fold (sum0);
 787               break;
 788             case NAT_PROTOCOL_UDP:
 789             case NAT_PROTOCOL_TCP:
 790               old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
 791               new_id0 = sm0.port;
 792               ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
 793
 794               sum0 = icmp0->checksum;
 795               sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
 796                                      dst_port);
 797               icmp0->checksum = ip_csum_fold (sum0);
 798               break;
 799             default:
 800               ASSERT (0);
 801             }
 802         }
 803     }
 804
 805   if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
 806     {
 807       if (sm->deterministic ||
 808           0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
 809                                       sm->endpoint_dependent))
 810         vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
 811     }
 812
 813 out:
 814   return next0;
 815 }
 816 #endif
 817
 818 static inline u32
 819 icmp_in2out_slow_path (snat_main_t * sm,
 820                        vlib_buffer_t * b0,
 821                        ip4_header_t * ip0,
 822                        icmp46_header_t * icmp0,
 823                        u32 sw_if_index0,
 824                        u32 rx_fib_index0,
 825                        vlib_node_runtime_t * node,
 826                        u32 next0,
 827                        f64 now, u32 thread_index, snat_session_t ** p_s0)
 828 {
 829   vlib_main_t *vm = vlib_get_main ();
 830
 831   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 832                        next0, thread_index, p_s0, 0);
 833   snat_session_t *s0 = *p_s0;
 834   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
 835     {
 836       /* Accounting */
 837       nat44_session_update_counters (s0, now,
 838                                      vlib_buffer_length_in_chain
 839                                      (vm, b0), thread_index);
 840       /* Per-user LRU list maintenance */
 841       nat44_session_update_lru (sm, s0, thread_index);
 842     }
 843   return next0;
 844 }
 845
 846 static int
 847 nat_in2out_sm_unknown_proto (snat_main_t * sm,
 848                              vlib_buffer_t * b,
 849                              ip4_header_t * ip, u32 rx_fib_index)
 850 {
 851   clib_bihash_kv_8_8_t kv, value;
 852   snat_static_mapping_t *m;
 853   snat_session_key_t m_key;
 854   u32 old_addr, new_addr;
 855   ip_csum_t sum;
 856
 857   m_key.addr = ip->src_address;
 858   m_key.port = 0;
 859   m_key.protocol = 0;
 860   m_key.fib_index = rx_fib_index;
 861   kv.key = m_key.as_u64;
 862   if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 863     return 1;
 864
 865   m = pool_elt_at_index (sm->static_mappings, value.value);
 866
 867   old_addr = ip->src_address.as_u32;
 868   new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 869   sum = ip->checksum;
 870   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 871   ip->checksum = ip_csum_fold (sum);
 872
 873
 874   /* Hairpinning */
 875   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 876     {
 877       vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 878       nat_hairpinning_sm_unknown_proto (sm, b, ip);
 879     }
 880
 881   return 0;
 882 }
 883
 884 static inline uword
 885 snat_in2out_node_fn_inline (vlib_main_t * vm,
 886                             vlib_node_runtime_t * node,
 887                             vlib_frame_t * frame, int is_slow_path,
 888                             int is_output_feature)
 889 {
 890   u32 n_left_from, *from, *to_next;
 891   snat_in2out_next_t next_index;
 892   u32 pkts_processed = 0;
 893   snat_main_t *sm = &snat_main;
 894   f64 now = vlib_time_now (vm);
 895   u32 stats_node_index;
 896   u32 thread_index = vm->thread_index;
 897   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 898     0, fragments = 0;
 899
 900   stats_node_index = is_slow_path ? sm->in2out_slowpath_node_index :
 901     sm->in2out_node_index;
 902
 903   from = vlib_frame_vector_args (frame);
 904   n_left_from = frame->n_vectors;
 905   next_index = node->cached_next_index;
 906
 907   while (n_left_from > 0)
 908     {
 909       u32 n_left_to_next;
 910
 911       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 912
 913       while (n_left_from >= 4 && n_left_to_next >= 2)
 914         {
 915           u32 bi0, bi1;
 916           vlib_buffer_t *b0, *b1;
 917           u32 next0, next1;
 918           u32 sw_if_index0, sw_if_index1;
 919           ip4_header_t *ip0, *ip1;
 920           ip_csum_t sum0, sum1;
 921           u32 new_addr0, old_addr0, new_addr1, old_addr1;
 922           u16 old_port0, new_port0, old_port1, new_port1;
 923           udp_header_t *udp0, *udp1;
 924           tcp_header_t *tcp0, *tcp1;
 925           icmp46_header_t *icmp0, *icmp1;
 926           snat_session_key_t key0, key1;
 927           u32 rx_fib_index0, rx_fib_index1;
 928           u32 proto0, proto1;
 929           snat_session_t *s0 = 0, *s1 = 0;
 930           clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
 931           u32 iph_offset0 = 0, iph_offset1 = 0;
 932
 933           /* Prefetch next iteration. */
 934           {
 935             vlib_buffer_t *p2, *p3;
 936
 937             p2 = vlib_get_buffer (vm, from[2]);
 938             p3 = vlib_get_buffer (vm, from[3]);
 939
 940             vlib_prefetch_buffer_header (p2, LOAD);
 941             vlib_prefetch_buffer_header (p3, LOAD);
 942
 943             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 944             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 945           }
 946
 947           /* speculatively enqueue b0 and b1 to the current next frame */
 948           to_next[0] = bi0 = from[0];
 949           to_next[1] = bi1 = from[1];
 950           from += 2;
 951           to_next += 2;
 952           n_left_from -= 2;
 953           n_left_to_next -= 2;
 954
 955           b0 = vlib_get_buffer (vm, bi0);
 956           b1 = vlib_get_buffer (vm, bi1);
 957
 958           if (is_output_feature)
 959             iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 960
 961           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 962                                   iph_offset0);
 963
 964           udp0 = ip4_next_header (ip0);
 965           tcp0 = (tcp_header_t *) udp0;
 966           icmp0 = (icmp46_header_t *) udp0;
 967
 968           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 969           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 970                                    sw_if_index0);
 971
 972           next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
 973
 974           if (PREDICT_FALSE (ip0->ttl == 1))
 975             {
 976               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 977               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 978                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 979                                            0);
 980               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
 981               goto trace00;
 982             }
 983
 984           proto0 = ip_proto_to_nat_proto (ip0->protocol);
 985
 986           /* Next configured feature, probably ip4-lookup */
 987           if (is_slow_path)
 988             {
 989               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 990                 {
 991                   if (nat_in2out_sm_unknown_proto
 992                       (sm, b0, ip0, rx_fib_index0))
 993                     {
 994                       next0 = SNAT_IN2OUT_NEXT_DROP;
 995                       b0->error =
 996                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
 997                     }
 998                   other_packets++;
 999                   goto trace00;
1000                 }
1001
1002               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1003                 {
1004                   next0 = icmp_in2out_slow_path
1005                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
1006                      node, next0, now, thread_index, &s0);
1007                   icmp_packets++;
1008                   goto trace00;
1009                 }
1010             }
1011           else
1012             {
1013               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1014                 {
1015                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1016                   goto trace00;
1017                 }
1018
1019               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1020                 {
1021                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1022                   goto trace00;
1023                 }
1024             }
1025
1026           key0.addr = ip0->src_address;
1027           key0.port = vnet_buffer (b0)->ip.reass.l4_src_port;
1028           key0.protocol = proto0;
1029           key0.fib_index = rx_fib_index0;
1030
1031           kv0.key = key0.as_u64;
1032
1033           if (PREDICT_FALSE
1034               (clib_bihash_search_8_8
1035                (&sm->per_thread_data[thread_index].in2out, &kv0,
1036                 &value0) != 0))
1037             {
1038               if (is_slow_path)
1039                 {
1040                   if (is_output_feature)
1041                     {
1042                       if (PREDICT_FALSE
1043                           (nat_not_translate_output_feature
1044                            (sm, ip0, proto0,
1045                             vnet_buffer (b0)->ip.reass.l4_src_port,
1046                             vnet_buffer (b0)->ip.reass.l4_dst_port,
1047                             thread_index, sw_if_index0)))
1048                         goto trace00;
1049
1050                       /*
1051                        * Send DHCP packets to the ipv4 stack, or we won't
1052                        * be able to use dhcp client on the outside interface
1053                        */
1054                       if (PREDICT_FALSE
1055                           (proto0 == NAT_PROTOCOL_UDP
1056                            && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1057                                clib_host_to_net_u16
1058                                (UDP_DST_PORT_dhcp_to_server))
1059                            && ip0->dst_address.as_u32 == 0xffffffff))
1060                         goto trace00;
1061                     }
1062                   else
1063                     {
1064                       if (PREDICT_FALSE
1065                           (snat_not_translate
1066                            (sm, node, sw_if_index0, ip0, proto0,
1067                             rx_fib_index0, thread_index)))
1068                         goto trace00;
1069                     }
1070
1071                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1072                                      &s0, node, next0, thread_index, now);
1073                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1074                     goto trace00;
1075
1076                   if (PREDICT_FALSE (!s0))
1077                     goto trace00;
1078                 }
1079               else
1080                 {
1081                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1082                   goto trace00;
1083                 }
1084             }
1085           else
1086             s0 =
1087               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1088                                  value0.value);
1089
1090           b0->flags |= VNET_BUFFER_F_IS_NATED;
1091
1092           old_addr0 = ip0->src_address.as_u32;
1093           ip0->src_address = s0->out2in.addr;
1094           new_addr0 = ip0->src_address.as_u32;
1095           if (!is_output_feature)
1096             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1097
1098           sum0 = ip0->checksum;
1099           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1100                                  ip4_header_t,
1101                                  src_address /* changed member */ );
1102           ip0->checksum = ip_csum_fold (sum0);
1103
1104
1105           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1106             {
1107               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1108                 {
1109                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1110                   new_port0 = udp0->src_port = s0->out2in.port;
1111                   sum0 = tcp0->checksum;
1112                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1113                                          ip4_header_t,
1114                                          dst_address /* changed member */ );
1115                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1116                                          ip4_header_t /* cheat */ ,
1117                                          length /* changed member */ );
1118                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1119                   tcp0->checksum = ip_csum_fold (sum0);
1120                 }
1121               tcp_packets++;
1122             }
1123           else
1124             {
1125               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1126                 {
1127                   udp0->src_port = s0->out2in.port;
1128                   if (PREDICT_FALSE (udp0->checksum))
1129                     {
1130                       old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1131                       new_port0 = udp0->src_port;
1132                       sum0 = udp0->checksum;
1133                       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address      /* changed member */
1134                         );
1135                       sum0 =
1136                         ip_csum_update (sum0, old_port0, new_port0,
1137                                         ip4_header_t /* cheat */ ,
1138                                         length /* changed member */ );
1139                       udp0->checksum = ip_csum_fold (sum0);
1140                     }
1141                 }
1142               udp_packets++;
1143             }
1144
1145           /* Accounting */
1146           nat44_session_update_counters (s0, now,
1147                                          vlib_buffer_length_in_chain (vm, b0),
1148                                          thread_index);
1149           /* Per-user LRU list maintenance */
1150           nat44_session_update_lru (sm, s0, thread_index);
1151         trace00:
1152
1153           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1154                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1155             {
1156               snat_in2out_trace_t *t =
1157                 vlib_add_trace (vm, node, b0, sizeof (*t));
1158               t->is_slow_path = is_slow_path;
1159               t->sw_if_index = sw_if_index0;
1160               t->next_index = next0;
1161               t->session_index = ~0;
1162               if (s0)
1163                 t->session_index =
1164                   s0 - sm->per_thread_data[thread_index].sessions;
1165             }
1166
1167           pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1168
1169           if (is_output_feature)
1170             iph_offset1 = vnet_buffer (b1)->ip.reass.save_rewrite_length;
1171
1172           ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1173                                   iph_offset1);
1174
1175           udp1 = ip4_next_header (ip1);
1176           tcp1 = (tcp_header_t *) udp1;
1177           icmp1 = (icmp46_header_t *) udp1;
1178
1179           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1180           rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1181                                    sw_if_index1);
1182
1183           if (PREDICT_FALSE (ip1->ttl == 1))
1184             {
1185               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1186               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1187                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1188                                            0);
1189               next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1190               goto trace01;
1191             }
1192
1193           proto1 = ip_proto_to_nat_proto (ip1->protocol);
1194
1195           /* Next configured feature, probably ip4-lookup */
1196           if (is_slow_path)
1197             {
1198               if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1199                 {
1200                   if (nat_in2out_sm_unknown_proto
1201                       (sm, b1, ip1, rx_fib_index1))
1202                     {
1203                       next1 = SNAT_IN2OUT_NEXT_DROP;
1204                       b1->error =
1205                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1206                     }
1207                   other_packets++;
1208                   goto trace01;
1209                 }
1210
1211               if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1212                 {
1213                   next1 = icmp_in2out_slow_path
1214                     (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1215                      next1, now, thread_index, &s1);
1216                   icmp_packets++;
1217                   goto trace01;
1218                 }
1219             }
1220           else
1221             {
1222               if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1223                 {
1224                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1225                   goto trace01;
1226                 }
1227
1228               if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1229                 {
1230                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1231                   goto trace01;
1232                 }
1233             }
1234
1235           key1.addr = ip1->src_address;
1236           key1.port = vnet_buffer (b1)->ip.reass.l4_src_port;
1237           key1.protocol = proto1;
1238           key1.fib_index = rx_fib_index1;
1239
1240           kv1.key = key1.as_u64;
1241
1242           if (PREDICT_FALSE
1243               (clib_bihash_search_8_8
1244                (&sm->per_thread_data[thread_index].in2out, &kv1,
1245                 &value1) != 0))
1246             {
1247               if (is_slow_path)
1248                 {
1249                   if (is_output_feature)
1250                     {
1251                       if (PREDICT_FALSE
1252                           (nat_not_translate_output_feature
1253                            (sm, ip1, proto1,
1254                             vnet_buffer (b1)->ip.reass.l4_src_port,
1255                             vnet_buffer (b1)->ip.reass.l4_dst_port,
1256                             thread_index, sw_if_index1)))
1257                         goto trace01;
1258
1259                       /*
1260                        * Send DHCP packets to the ipv4 stack, or we won't
1261                        * be able to use dhcp client on the outside interface
1262                        */
1263                       if (PREDICT_FALSE
1264                           (proto1 == NAT_PROTOCOL_UDP
1265                            && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
1266                                clib_host_to_net_u16
1267                                (UDP_DST_PORT_dhcp_to_server))
1268                            && ip1->dst_address.as_u32 == 0xffffffff))
1269                         goto trace01;
1270                     }
1271                   else
1272                     {
1273                       if (PREDICT_FALSE
1274                           (snat_not_translate
1275                            (sm, node, sw_if_index1, ip1, proto1,
1276                             rx_fib_index1, thread_index)))
1277                         goto trace01;
1278                     }
1279
1280                   next1 = slow_path (sm, b1, ip1, rx_fib_index1, &key1,
1281                                      &s1, node, next1, thread_index, now);
1282                   if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1283                     goto trace01;
1284
1285                   if (PREDICT_FALSE (!s1))
1286                     goto trace01;
1287                 }
1288               else
1289                 {
1290                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1291                   goto trace01;
1292                 }
1293             }
1294           else
1295             s1 =
1296               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1297                                  value1.value);
1298
1299           b1->flags |= VNET_BUFFER_F_IS_NATED;
1300
1301           old_addr1 = ip1->src_address.as_u32;
1302           ip1->src_address = s1->out2in.addr;
1303           new_addr1 = ip1->src_address.as_u32;
1304           if (!is_output_feature)
1305             vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1306
1307           sum1 = ip1->checksum;
1308           sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1309                                  ip4_header_t,
1310                                  src_address /* changed member */ );
1311           ip1->checksum = ip_csum_fold (sum1);
1312
1313           if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
1314             {
1315               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1316                 {
1317                   old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1318                   new_port1 = udp1->src_port = s1->out2in.port;
1319                   sum1 = tcp1->checksum;
1320                   sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1321                                          ip4_header_t,
1322                                          dst_address /* changed member */ );
1323                   sum1 = ip_csum_update (sum1, old_port1, new_port1,
1324                                          ip4_header_t /* cheat */ ,
1325                                          length /* changed member */ );
1326                   mss_clamping (sm->mss_clamping, tcp1, &sum1);
1327                   tcp1->checksum = ip_csum_fold (sum1);
1328                 }
1329               tcp_packets++;
1330             }
1331           else
1332             {
1333               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1334                 {
1335                   udp1->src_port = s1->out2in.port;
1336                   if (PREDICT_FALSE (udp1->checksum))
1337                     {
1338                       old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1339                       new_port1 = udp1->src_port;
1340                       sum1 = udp1->checksum;
1341                       sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t, dst_address      /* changed member */
1342                         );
1343                       sum1 =
1344                         ip_csum_update (sum1, old_port1, new_port1,
1345                                         ip4_header_t /* cheat */ ,
1346                                         length /* changed member */ );
1347                       udp1->checksum = ip_csum_fold (sum1);
1348                     }
1349                 }
1350               udp_packets++;
1351             }
1352
1353           /* Accounting */
1354           nat44_session_update_counters (s1, now,
1355                                          vlib_buffer_length_in_chain (vm, b1),
1356                                          thread_index);
1357           /* Per-user LRU list maintenance */
1358           nat44_session_update_lru (sm, s1, thread_index);
1359         trace01:
1360
1361           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1362                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1363             {
1364               snat_in2out_trace_t *t =
1365                 vlib_add_trace (vm, node, b1, sizeof (*t));
1366               t->sw_if_index = sw_if_index1;
1367               t->next_index = next1;
1368               t->session_index = ~0;
1369               if (s1)
1370                 t->session_index =
1371                   s1 - sm->per_thread_data[thread_index].sessions;
1372             }
1373
1374           pkts_processed += next1 == SNAT_IN2OUT_NEXT_LOOKUP;
1375
1376           /* verify speculative enqueues, maybe switch current next frame */
1377           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1378                                            to_next, n_left_to_next,
1379                                            bi0, bi1, next0, next1);
1380         }
1381
1382       while (n_left_from > 0 && n_left_to_next > 0)
1383         {
1384           u32 bi0;
1385           vlib_buffer_t *b0;
1386           u32 next0;
1387           u32 sw_if_index0;
1388           ip4_header_t *ip0;
1389           ip_csum_t sum0;
1390           u32 new_addr0, old_addr0;
1391           u16 old_port0, new_port0;
1392           udp_header_t *udp0;
1393           tcp_header_t *tcp0;
1394           icmp46_header_t *icmp0;
1395           snat_session_key_t key0;
1396           u32 rx_fib_index0;
1397           u32 proto0;
1398           snat_session_t *s0 = 0;
1399           clib_bihash_kv_8_8_t kv0, value0;
1400           u32 iph_offset0 = 0;
1401
1402           /* speculatively enqueue b0 to the current next frame */
1403           bi0 = from[0];
1404           to_next[0] = bi0;
1405           from += 1;
1406           to_next += 1;
1407           n_left_from -= 1;
1408           n_left_to_next -= 1;
1409
1410           b0 = vlib_get_buffer (vm, bi0);
1411           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1412
1413           if (is_output_feature)
1414             iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1415
1416           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1417                                   iph_offset0);
1418
1419           udp0 = ip4_next_header (ip0);
1420           tcp0 = (tcp_header_t *) udp0;
1421           icmp0 = (icmp46_header_t *) udp0;
1422
1423           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1424           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1425                                    sw_if_index0);
1426
1427           if (PREDICT_FALSE (ip0->ttl == 1))
1428             {
1429               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1430               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1431                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1432                                            0);
1433               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1434               goto trace0;
1435             }
1436
1437           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1438
1439           /* Next configured feature, probably ip4-lookup */
1440           if (is_slow_path)
1441             {
1442               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1443                 {
1444                   if (nat_in2out_sm_unknown_proto
1445                       (sm, b0, ip0, rx_fib_index0))
1446                     {
1447                       next0 = SNAT_IN2OUT_NEXT_DROP;
1448                       b0->error =
1449                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1450                     }
1451                   other_packets++;
1452                   goto trace0;
1453                 }
1454
1455               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1456                 {
1457                   next0 = icmp_in2out_slow_path
1458                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1459                      next0, now, thread_index, &s0);
1460                   icmp_packets++;
1461                   goto trace0;
1462                 }
1463             }
1464           else
1465             {
1466               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1467                 {
1468                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1469                   goto trace0;
1470                 }
1471
1472               if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1473                 {
1474                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1475                   goto trace0;
1476                 }
1477             }
1478
1479           key0.addr = ip0->src_address;
1480           key0.port = vnet_buffer (b0)->ip.reass.l4_src_port;
1481           key0.protocol = proto0;
1482           key0.fib_index = rx_fib_index0;
1483
1484           kv0.key = key0.as_u64;
1485
1486           if (clib_bihash_search_8_8
1487               (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1488             {
1489               if (is_slow_path)
1490                 {
1491                   if (is_output_feature)
1492                     {
1493                       if (PREDICT_FALSE
1494                           (nat_not_translate_output_feature
1495                            (sm, ip0, proto0,
1496                             vnet_buffer (b0)->ip.reass.l4_src_port,
1497                             vnet_buffer (b0)->ip.reass.l4_dst_port,
1498                             thread_index, sw_if_index0)))
1499                         goto trace0;
1500
1501                       /*
1502                        * Send DHCP packets to the ipv4 stack, or we won't
1503                        * be able to use dhcp client on the outside interface
1504                        */
1505                       if (PREDICT_FALSE
1506                           (proto0 == NAT_PROTOCOL_UDP
1507                            && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1508                                clib_host_to_net_u16
1509                                (UDP_DST_PORT_dhcp_to_server))
1510                            && ip0->dst_address.as_u32 == 0xffffffff))
1511                         goto trace0;
1512                     }
1513                   else
1514                     {
1515                       if (PREDICT_FALSE
1516                           (snat_not_translate
1517                            (sm, node, sw_if_index0, ip0, proto0,
1518                             rx_fib_index0, thread_index)))
1519                         goto trace0;
1520                     }
1521
1522                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1523                                      &s0, node, next0, thread_index, now);
1524
1525                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1526                     goto trace0;
1527
1528                   if (PREDICT_FALSE (!s0))
1529                     goto trace0;
1530                 }
1531               else
1532                 {
1533                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1534                   goto trace0;
1535                 }
1536             }
1537           else
1538             s0 =
1539               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1540                                  value0.value);
1541
1542           b0->flags |= VNET_BUFFER_F_IS_NATED;
1543
1544           old_addr0 = ip0->src_address.as_u32;
1545           ip0->src_address = s0->out2in.addr;
1546           new_addr0 = ip0->src_address.as_u32;
1547           if (!is_output_feature)
1548             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1549
1550           sum0 = ip0->checksum;
1551           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1552                                  ip4_header_t,
1553                                  src_address /* changed member */ );
1554           ip0->checksum = ip_csum_fold (sum0);
1555
1556           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1557             {
1558               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1559                 {
1560                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1561                   new_port0 = udp0->src_port = s0->out2in.port;
1562                   sum0 = tcp0->checksum;
1563                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1564                                          ip4_header_t,
1565                                          dst_address /* changed member */ );
1566                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1567                                          ip4_header_t /* cheat */ ,
1568                                          length /* changed member */ );
1569                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1570                   tcp0->checksum = ip_csum_fold (sum0);
1571                 }
1572               tcp_packets++;
1573             }
1574           else
1575             {
1576               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1577                 {
1578                   udp0->src_port = s0->out2in.port;
1579                   if (PREDICT_FALSE (udp0->checksum))
1580                     {
1581                       old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1582                       new_port0 = udp0->src_port;
1583                       sum0 = udp0->checksum;
1584                       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address      /* changed member */
1585                         );
1586                       sum0 =
1587                         ip_csum_update (sum0, old_port0, new_port0,
1588                                         ip4_header_t /* cheat */ ,
1589                                         length /* changed member */ );
1590                       udp0->checksum = ip_csum_fold (sum0);
1591                     }
1592                 }
1593               udp_packets++;
1594             }
1595
1596           /* Accounting */
1597           nat44_session_update_counters (s0, now,
1598                                          vlib_buffer_length_in_chain (vm, b0),
1599                                          thread_index);
1600           /* Per-user LRU list maintenance */
1601           nat44_session_update_lru (sm, s0, thread_index);
1602
1603         trace0:
1604           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1605                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1606             {
1607               snat_in2out_trace_t *t =
1608                 vlib_add_trace (vm, node, b0, sizeof (*t));
1609               t->is_slow_path = is_slow_path;
1610               t->sw_if_index = sw_if_index0;
1611               t->next_index = next0;
1612               t->session_index = ~0;
1613               if (s0)
1614                 t->session_index =
1615                   s0 - sm->per_thread_data[thread_index].sessions;
1616             }
1617
1618           pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1619
1620           /* verify speculative enqueue, maybe switch current next frame */
1621           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1622                                            to_next, n_left_to_next,
1623                                            bi0, next0);
1624         }
1625
1626       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1627     }
1628
1629   vlib_node_increment_counter (vm, stats_node_index,
1630                                SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
1631                                pkts_processed);
1632   vlib_node_increment_counter (vm, stats_node_index,
1633                                SNAT_IN2OUT_ERROR_TCP_PACKETS, tcp_packets);
1634   vlib_node_increment_counter (vm, stats_node_index,
1635                                SNAT_IN2OUT_ERROR_UDP_PACKETS, udp_packets);
1636   vlib_node_increment_counter (vm, stats_node_index,
1637                                SNAT_IN2OUT_ERROR_ICMP_PACKETS, icmp_packets);
1638   vlib_node_increment_counter (vm, stats_node_index,
1639                                SNAT_IN2OUT_ERROR_OTHER_PACKETS,
1640                                other_packets);
1641   vlib_node_increment_counter (vm, stats_node_index,
1642                                SNAT_IN2OUT_ERROR_FRAGMENTS, fragments);
1643
1644   return frame->n_vectors;
1645 }
1646
1647 VLIB_NODE_FN (snat_in2out_node) (vlib_main_t * vm,
1648                                  vlib_node_runtime_t * node,
1649                                  vlib_frame_t * frame)
1650 {
1651   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1652                                      0);
1653 }
1654
1655 /* *INDENT-OFF* */
1656 VLIB_REGISTER_NODE (snat_in2out_node) = {
1657   .name = "nat44-in2out",
1658   .vector_size = sizeof (u32),
1659   .format_trace = format_snat_in2out_trace,
1660   .type = VLIB_NODE_TYPE_INTERNAL,
1661
1662   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1663   .error_strings = snat_in2out_error_strings,
1664
1665   .runtime_data_bytes = sizeof (snat_runtime_t),
1666
1667   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1668
1669   /* edit / add dispositions here */
1670   .next_nodes = {
1671     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1672     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1673     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1674     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1675   },
1676 };
1677 /* *INDENT-ON* */
1678
1679 VLIB_NODE_FN (snat_in2out_output_node) (vlib_main_t * vm,
1680                                         vlib_node_runtime_t * node,
1681                                         vlib_frame_t * frame)
1682 {
1683   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1684                                      1);
1685 }
1686
1687 /* *INDENT-OFF* */
1688 VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1689   .name = "nat44-in2out-output",
1690   .vector_size = sizeof (u32),
1691   .format_trace = format_snat_in2out_trace,
1692   .type = VLIB_NODE_TYPE_INTERNAL,
1693
1694   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1695   .error_strings = snat_in2out_error_strings,
1696
1697   .runtime_data_bytes = sizeof (snat_runtime_t),
1698
1699   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1700
1701   /* edit / add dispositions here */
1702   .next_nodes = {
1703     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1704     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1705     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1706     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1707   },
1708 };
1709 /* *INDENT-ON* */
1710
1711 VLIB_NODE_FN (snat_in2out_slowpath_node) (vlib_main_t * vm,
1712                                           vlib_node_runtime_t * node,
1713                                           vlib_frame_t * frame)
1714 {
1715   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1716                                      0);
1717 }
1718
1719 /* *INDENT-OFF* */
1720 VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1721   .name = "nat44-in2out-slowpath",
1722   .vector_size = sizeof (u32),
1723   .format_trace = format_snat_in2out_trace,
1724   .type = VLIB_NODE_TYPE_INTERNAL,
1725
1726   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1727   .error_strings = snat_in2out_error_strings,
1728
1729   .runtime_data_bytes = sizeof (snat_runtime_t),
1730
1731   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1732
1733   /* edit / add dispositions here */
1734   .next_nodes = {
1735     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1736     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1737     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1738     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1739   },
1740 };
1741 /* *INDENT-ON* */
1742
1743 VLIB_NODE_FN (snat_in2out_output_slowpath_node) (vlib_main_t * vm,
1744                                                  vlib_node_runtime_t * node,
1745                                                  vlib_frame_t * frame)
1746 {
1747   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1748                                      1);
1749 }
1750
1751 /* *INDENT-OFF* */
1752 VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1753   .name = "nat44-in2out-output-slowpath",
1754   .vector_size = sizeof (u32),
1755   .format_trace = format_snat_in2out_trace,
1756   .type = VLIB_NODE_TYPE_INTERNAL,
1757
1758   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1759   .error_strings = snat_in2out_error_strings,
1760
1761   .runtime_data_bytes = sizeof (snat_runtime_t),
1762
1763   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1764
1765   /* edit / add dispositions here */
1766   .next_nodes = {
1767     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1768     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1769     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1770     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1771   },
1772 };
1773 /* *INDENT-ON* */
1774
1775 VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
1776                                       vlib_node_runtime_t * node,
1777                                       vlib_frame_t * frame)
1778 {
1779   u32 n_left_from, *from, *to_next;
1780   snat_in2out_next_t next_index;
1781   u32 pkts_processed = 0;
1782   snat_main_t *sm = &snat_main;
1783   u32 stats_node_index;
1784   int is_hairpinning = 0;
1785
1786   stats_node_index = sm->in2out_fast_node_index;
1787
1788   from = vlib_frame_vector_args (frame);
1789   n_left_from = frame->n_vectors;
1790   next_index = node->cached_next_index;
1791
1792   while (n_left_from > 0)
1793     {
1794       u32 n_left_to_next;
1795
1796       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1797
1798       while (n_left_from > 0 && n_left_to_next > 0)
1799         {
1800           u32 bi0;
1801           vlib_buffer_t *b0;
1802           u32 next0;
1803           u32 sw_if_index0;
1804           ip4_header_t *ip0;
1805           ip_csum_t sum0;
1806           u32 new_addr0, old_addr0;
1807           u16 old_port0, new_port0;
1808           udp_header_t *udp0;
1809           tcp_header_t *tcp0;
1810           icmp46_header_t *icmp0;
1811           snat_session_key_t key0, sm0;
1812           u32 proto0;
1813           u32 rx_fib_index0;
1814
1815           /* speculatively enqueue b0 to the current next frame */
1816           bi0 = from[0];
1817           to_next[0] = bi0;
1818           from += 1;
1819           to_next += 1;
1820           n_left_from -= 1;
1821           n_left_to_next -= 1;
1822
1823           b0 = vlib_get_buffer (vm, bi0);
1824           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1825
1826           ip0 = vlib_buffer_get_current (b0);
1827           udp0 = ip4_next_header (ip0);
1828           tcp0 = (tcp_header_t *) udp0;
1829           icmp0 = (icmp46_header_t *) udp0;
1830
1831           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1832           rx_fib_index0 =
1833             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
1834
1835           if (PREDICT_FALSE (ip0->ttl == 1))
1836             {
1837               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1838               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1839                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1840                                            0);
1841               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1842               goto trace0;
1843             }
1844
1845           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1846
1847           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1848             goto trace0;
1849
1850           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1851             {
1852               next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
1853                                    rx_fib_index0, node, next0, ~0, 0, 0);
1854               goto trace0;
1855             }
1856
1857           key0.addr = ip0->src_address;
1858           key0.protocol = proto0;
1859           key0.port = udp0->src_port;
1860           key0.fib_index = rx_fib_index0;
1861
1862           if (snat_static_mapping_match (sm, key0, &sm0, 0, 0, 0, 0, 0, 0))
1863             {
1864               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
1865               next0 = SNAT_IN2OUT_NEXT_DROP;
1866               goto trace0;
1867             }
1868
1869           new_addr0 = sm0.addr.as_u32;
1870           new_port0 = sm0.port;
1871           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
1872           old_addr0 = ip0->src_address.as_u32;
1873           ip0->src_address.as_u32 = new_addr0;
1874
1875           sum0 = ip0->checksum;
1876           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1877                                  ip4_header_t,
1878                                  src_address /* changed member */ );
1879           ip0->checksum = ip_csum_fold (sum0);
1880
1881           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
1882             {
1883               old_port0 = udp0->src_port;
1884               udp0->src_port = new_port0;
1885
1886               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1887                 {
1888                   sum0 = tcp0->checksum;
1889                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1890                                          ip4_header_t,
1891                                          dst_address /* changed member */ );
1892                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1893                                          ip4_header_t /* cheat */ ,
1894                                          length /* changed member */ );
1895                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1896                   tcp0->checksum = ip_csum_fold (sum0);
1897                 }
1898               else if (udp0->checksum)
1899                 {
1900                   sum0 = udp0->checksum;
1901                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1902                                          ip4_header_t,
1903                                          dst_address /* changed member */ );
1904                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1905                                          ip4_header_t /* cheat */ ,
1906                                          length /* changed member */ );
1907                   udp0->checksum = ip_csum_fold (sum0);
1908                 }
1909             }
1910           else
1911             {
1912               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1913                 {
1914                   sum0 = tcp0->checksum;
1915                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1916                                          ip4_header_t,
1917                                          dst_address /* changed member */ );
1918                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1919                   tcp0->checksum = ip_csum_fold (sum0);
1920                 }
1921               else if (udp0->checksum)
1922                 {
1923                   sum0 = udp0->checksum;
1924                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1925                                          ip4_header_t,
1926                                          dst_address /* changed member */ );
1927                   udp0->checksum = ip_csum_fold (sum0);
1928                 }
1929             }
1930
1931           /* Hairpinning */
1932           snat_hairpinning (vm, node, sm, b0, ip0, udp0, tcp0, proto0, 0,
1933                             0 /* do_trace */ );
1934           is_hairpinning = 1;
1935
1936         trace0:
1937           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1938                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1939             {
1940               snat_in2out_trace_t *t =
1941                 vlib_add_trace (vm, node, b0, sizeof (*t));
1942               t->sw_if_index = sw_if_index0;
1943               t->next_index = next0;
1944               t->is_hairpinning = is_hairpinning;
1945             }
1946
1947           pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
1948
1949           /* verify speculative enqueue, maybe switch current next frame */
1950           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1951                                            to_next, n_left_to_next,
1952                                            bi0, next0);
1953         }
1954
1955       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1956     }
1957
1958   vlib_node_increment_counter (vm, stats_node_index,
1959                                SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
1960                                pkts_processed);
1961   return frame->n_vectors;
1962 }
1963
1964
1965 /* *INDENT-OFF* */
1966 VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
1967   .name = "nat44-in2out-fast",
1968   .vector_size = sizeof (u32),
1969   .format_trace = format_snat_in2out_fast_trace,
1970   .type = VLIB_NODE_TYPE_INTERNAL,
1971
1972   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1973   .error_strings = snat_in2out_error_strings,
1974
1975   .runtime_data_bytes = sizeof (snat_runtime_t),
1976
1977   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1978
1979   /* edit / add dispositions here */
1980   .next_nodes = {
1981     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1982     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1983     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1984     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1985   },
1986 };
1987 /* *INDENT-ON* */
1988
1989 /*
1990  * fd.io coding-style-patch-verification: ON
1991  *
1992  * Local Variables:
1993  * eval: (c-set-style "gnu")
1994  * End:
1995  */