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_reass.h>
  31 #include <nat/nat_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
  39 typedef struct
  40 {
  41   u32 sw_if_index;
  42   u32 next_index;
  43   u32 session_index;
  44   u32 is_slow_path;
  45 } snat_in2out_trace_t;
  46
  47 /* packet trace format function */
  48 static u8 *
  49 format_snat_in2out_trace (u8 * s, va_list * args)
  50 {
  51   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  52   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  53   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  54   char *tag;
  55
  56   tag = t->is_slow_path ? "NAT44_IN2OUT_SLOW_PATH" : "NAT44_IN2OUT_FAST_PATH";
  57
  58   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  59               t->sw_if_index, t->next_index, t->session_index);
  60
  61   return s;
  62 }
  63
  64 static u8 *
  65 format_snat_in2out_fast_trace (u8 * s, va_list * args)
  66 {
  67   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  68   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  69   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  70
  71   s = format (s, "NAT44_IN2OUT_FAST: sw_if_index %d, next index %d",
  72               t->sw_if_index, t->next_index);
  73
  74   return s;
  75 }
  76
  77 #define foreach_snat_in2out_error                       \
  78 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
  79 _(IN2OUT_PACKETS, "good in2out packets processed")      \
  80 _(OUT_OF_PORTS, "out of ports")                         \
  81 _(BAD_OUTSIDE_FIB, "outside VRF ID not found")          \
  82 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  83 _(NO_TRANSLATION, "no translation")                     \
  84 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
  85 _(DROP_FRAGMENT, "drop fragment")                       \
  86 _(MAX_REASS, "maximum reassemblies exceeded")           \
  87 _(MAX_FRAG, "maximum fragments per reassembly exceeded")\
  88 _(TCP_PACKETS, "TCP packets")                           \
  89 _(UDP_PACKETS, "UDP packets")                           \
  90 _(ICMP_PACKETS, "ICMP packets")                         \
  91 _(OTHER_PACKETS, "other protocol packets")              \
  92 _(FRAGMENTS, "fragments")                               \
  93 _(CACHED_FRAGMENTS, "cached fragments")                 \
  94 _(PROCESSED_FRAGMENTS, "processed fragments")
  95
  96 typedef enum
  97 {
  98 #define _(sym,str) SNAT_IN2OUT_ERROR_##sym,
  99   foreach_snat_in2out_error
 100 #undef _
 101     SNAT_IN2OUT_N_ERROR,
 102 } snat_in2out_error_t;
 103
 104 static char *snat_in2out_error_strings[] = {
 105 #define _(sym,string) string,
 106   foreach_snat_in2out_error
 107 #undef _
 108 };
 109
 110 typedef enum
 111 {
 112   SNAT_IN2OUT_NEXT_LOOKUP,
 113   SNAT_IN2OUT_NEXT_DROP,
 114   SNAT_IN2OUT_NEXT_ICMP_ERROR,
 115   SNAT_IN2OUT_NEXT_SLOW_PATH,
 116   SNAT_IN2OUT_NEXT_REASS,
 117   SNAT_IN2OUT_N_NEXT,
 118 } snat_in2out_next_t;
 119
 120 static inline int
 121 snat_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 122                     u32 sw_if_index0, ip4_header_t * ip0, u32 proto0,
 123                     u32 rx_fib_index0, u32 thread_index)
 124 {
 125   udp_header_t *udp0 = ip4_next_header (ip0);
 126   snat_session_key_t key0, sm0;
 127   clib_bihash_kv_8_8_t kv0, value0;
 128
 129   key0.addr = ip0->dst_address;
 130   key0.port = udp0->dst_port;
 131   key0.protocol = proto0;
 132   key0.fib_index = sm->outside_fib_index;
 133   kv0.key = key0.as_u64;
 134
 135   /* NAT packet aimed at external address if */
 136   /* has active sessions */
 137   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
 138                               &value0))
 139     {
 140       /* or is static mappings */
 141       if (!snat_static_mapping_match (sm, key0, &sm0, 1, 0, 0, 0, 0, 0))
 142         return 0;
 143     }
 144   else
 145     return 0;
 146
 147   if (sm->forwarding_enabled)
 148     return 1;
 149
 150   return snat_not_translate_fast (sm, node, sw_if_index0, ip0, proto0,
 151                                   rx_fib_index0);
 152 }
 153
 154 static inline int
 155 nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
 156                                   u32 proto0, u16 src_port, u16 dst_port,
 157                                   u32 thread_index, u32 sw_if_index)
 158 {
 159   snat_session_key_t key0;
 160   clib_bihash_kv_8_8_t kv0, value0;
 161   snat_interface_t *i;
 162
 163   /* src NAT check */
 164   key0.addr = ip0->src_address;
 165   key0.port = src_port;
 166   key0.protocol = proto0;
 167   key0.fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 168   kv0.key = key0.as_u64;
 169
 170   if (!clib_bihash_search_8_8
 171       (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
 172     return 1;
 173
 174   /* dst NAT check */
 175   key0.addr = ip0->dst_address;
 176   key0.port = dst_port;
 177   key0.protocol = proto0;
 178   kv0.key = key0.as_u64;
 179   if (!clib_bihash_search_8_8
 180       (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
 181     {
 182       /* hairpinning */
 183     /* *INDENT-OFF* */
 184     pool_foreach (i, sm->output_feature_interfaces,
 185     ({
 186       if ((nat_interface_is_inside(i)) && (sw_if_index == i->sw_if_index))
 187         return 0;
 188     }));
 189     /* *INDENT-ON* */
 190       return 1;
 191     }
 192
 193   return 0;
 194 }
 195
 196 #ifndef CLIB_MARCH_VARIANT
 197 int
 198 nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
 199 {
 200   snat_main_t *sm = &snat_main;
 201   nat44_is_idle_session_ctx_t *ctx = arg;
 202   snat_session_t *s;
 203   u64 sess_timeout_time;
 204   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 205                                                        ctx->thread_index);
 206   clib_bihash_kv_8_8_t s_kv;
 207
 208   s = pool_elt_at_index (tsm->sessions, kv->value);
 209   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 210   if (ctx->now >= sess_timeout_time)
 211     {
 212       s_kv.key = s->out2in.as_u64;
 213       if (clib_bihash_add_del_8_8 (&tsm->out2in, &s_kv, 0))
 214         nat_elog_warn ("out2in key del failed");
 215
 216       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 217                                            s->in2out.addr.as_u32,
 218                                            s->out2in.addr.as_u32,
 219                                            s->in2out.protocol,
 220                                            s->in2out.port,
 221                                            s->out2in.port,
 222                                            s->in2out.fib_index);
 223
 224       nat_syslog_nat44_apmdel (s->user_index, s->in2out.fib_index,
 225                                &s->in2out.addr, s->in2out.port,
 226                                &s->out2in.addr, s->out2in.port,
 227                                s->in2out.protocol);
 228
 229       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 230                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 231                    ctx->thread_index);
 232
 233       if (!snat_is_session_static (s))
 234         snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 235                                             &s->out2in);
 236
 237       nat44_delete_session (sm, s, ctx->thread_index);
 238       return 1;
 239     }
 240
 241   return 0;
 242 }
 243 #endif
 244
 245 static u32
 246 slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 247            ip4_header_t * ip0,
 248            u32 rx_fib_index0,
 249            snat_session_key_t * key0,
 250            snat_session_t ** sessionp,
 251            vlib_node_runtime_t * node, u32 next0, u32 thread_index, f64 now)
 252 {
 253   snat_user_t *u;
 254   snat_session_t *s = 0;
 255   clib_bihash_kv_8_8_t kv0;
 256   snat_session_key_t key1;
 257   udp_header_t *udp0 = ip4_next_header (ip0);
 258   u8 is_sm = 0;
 259   nat_outside_fib_t *outside_fib;
 260   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 261   u8 identity_nat;
 262   fib_prefix_t pfx = {
 263     .fp_proto = FIB_PROTOCOL_IP4,
 264     .fp_len = 32,
 265     .fp_addr = {
 266                 .ip4.as_u32 = ip0->dst_address.as_u32,
 267                 },
 268   };
 269   nat44_is_idle_session_ctx_t ctx0;
 270
 271   if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 272     {
 273       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_SESSIONS_EXCEEDED];
 274       nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 275       nat_elog_notice ("maximum sessions exceeded");
 276       return SNAT_IN2OUT_NEXT_DROP;
 277     }
 278
 279   key1.protocol = key0->protocol;
 280
 281   /* First try to match static mapping by local address and port */
 282   if (snat_static_mapping_match
 283       (sm, *key0, &key1, 0, 0, 0, 0, 0, &identity_nat))
 284     {
 285       /* Try to create dynamic translation */
 286       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index0,
 287                                                thread_index, &key1,
 288                                                sm->port_per_thread,
 289                                                sm->per_thread_data
 290                                                [thread_index].snat_thread_index))
 291         {
 292           b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
 293           return SNAT_IN2OUT_NEXT_DROP;
 294         }
 295     }
 296   else
 297     {
 298       if (PREDICT_FALSE (identity_nat))
 299         {
 300           *sessionp = s;
 301           return next0;
 302         }
 303
 304       is_sm = 1;
 305     }
 306
 307   u = nat_user_get_or_create (sm, &ip0->src_address, rx_fib_index0,
 308                               thread_index);
 309   if (!u)
 310     {
 311       nat_elog_warn ("create NAT user failed");
 312       return SNAT_IN2OUT_NEXT_DROP;
 313     }
 314
 315   s = nat_session_alloc_or_recycle (sm, u, thread_index, now);
 316   if (!s)
 317     {
 318       nat44_delete_user_with_no_session (sm, u, thread_index);
 319       nat_elog_warn ("create NAT session failed");
 320       return SNAT_IN2OUT_NEXT_DROP;
 321     }
 322
 323   if (is_sm)
 324     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 325   user_session_increment (sm, u, is_sm);
 326   s->in2out = *key0;
 327   s->out2in = key1;
 328   s->out2in.protocol = key0->protocol;
 329   s->out2in.fib_index = sm->outside_fib_index;
 330   switch (vec_len (sm->outside_fibs))
 331     {
 332     case 0:
 333       s->out2in.fib_index = sm->outside_fib_index;
 334       break;
 335     case 1:
 336       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 337       break;
 338     default:
 339       /* *INDENT-OFF* */
 340       vec_foreach (outside_fib, sm->outside_fibs)
 341         {
 342           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 343           if (FIB_NODE_INDEX_INVALID != fei)
 344             {
 345               if (fib_entry_get_resolving_interface (fei) != ~0)
 346                 {
 347                   s->out2in.fib_index = outside_fib->fib_index;
 348                   break;
 349                 }
 350             }
 351         }
 352       /* *INDENT-ON* */
 353       break;
 354     }
 355   s->ext_host_addr.as_u32 = ip0->dst_address.as_u32;
 356   s->ext_host_port = udp0->dst_port;
 357   *sessionp = s;
 358
 359   /* Add to translation hashes */
 360   ctx0.now = now;
 361   ctx0.thread_index = thread_index;
 362   kv0.key = s->in2out.as_u64;
 363   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 364   if (clib_bihash_add_or_overwrite_stale_8_8
 365       (&sm->per_thread_data[thread_index].in2out, &kv0,
 366        nat44_i2o_is_idle_session_cb, &ctx0))
 367     nat_elog_notice ("in2out key add failed");
 368
 369   kv0.key = s->out2in.as_u64;
 370   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 371
 372   if (clib_bihash_add_or_overwrite_stale_8_8
 373       (&sm->per_thread_data[thread_index].out2in, &kv0,
 374        nat44_o2i_is_idle_session_cb, &ctx0))
 375     nat_elog_notice ("out2in key add failed");
 376
 377   /* log NAT event */
 378   snat_ipfix_logging_nat44_ses_create (thread_index,
 379                                        s->in2out.addr.as_u32,
 380                                        s->out2in.addr.as_u32,
 381                                        s->in2out.protocol,
 382                                        s->in2out.port,
 383                                        s->out2in.port, s->in2out.fib_index);
 384
 385   nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
 386                            &s->in2out.addr, s->in2out.port, &s->out2in.addr,
 387                            s->out2in.port, s->in2out.protocol);
 388
 389   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 390                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 391                &s->ext_host_nat_addr, s->ext_host_nat_port,
 392                s->in2out.protocol, s->in2out.fib_index, s->flags,
 393                thread_index, 0);
 394
 395   return next0;
 396 }
 397
 398 #ifndef CLIB_MARCH_VARIANT
 399 static_always_inline
 400   snat_in2out_error_t icmp_get_key (ip4_header_t * ip0,
 401                                     snat_session_key_t * p_key0)
 402 {
 403   icmp46_header_t *icmp0;
 404   snat_session_key_t key0;
 405   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 406   ip4_header_t *inner_ip0 = 0;
 407   void *l4_header = 0;
 408   icmp46_header_t *inner_icmp0;
 409
 410   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 411   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 412
 413   if (!icmp_is_error_message (icmp0))
 414     {
 415       key0.protocol = SNAT_PROTOCOL_ICMP;
 416       key0.addr = ip0->src_address;
 417       key0.port = echo0->identifier;
 418     }
 419   else
 420     {
 421       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 422       l4_header = ip4_next_header (inner_ip0);
 423       key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
 424       key0.addr = inner_ip0->dst_address;
 425       switch (key0.protocol)
 426         {
 427         case SNAT_PROTOCOL_ICMP:
 428           inner_icmp0 = (icmp46_header_t *) l4_header;
 429           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 430           key0.port = inner_echo0->identifier;
 431           break;
 432         case SNAT_PROTOCOL_UDP:
 433         case SNAT_PROTOCOL_TCP:
 434           key0.port = ((tcp_udp_header_t *) l4_header)->dst_port;
 435           break;
 436         default:
 437           return SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL;
 438         }
 439     }
 440   *p_key0 = key0;
 441   return -1;                    /* success */
 442 }
 443
 444 /**
 445  * Get address and port values to be used for ICMP packet translation
 446  * and create session if needed
 447  *
 448  * @param[in,out] sm             NAT main
 449  * @param[in,out] node           NAT node runtime
 450  * @param[in] thread_index       thread index
 451  * @param[in,out] b0             buffer containing packet to be translated
 452  * @param[out] p_proto           protocol used for matching
 453  * @param[out] p_value           address and port after NAT translation
 454  * @param[out] p_dont_translate  if packet should not be translated
 455  * @param d                      optional parameter
 456  * @param e                      optional parameter
 457  */
 458 u32
 459 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
 460                         u32 thread_index, vlib_buffer_t * b0,
 461                         ip4_header_t * ip0, u8 * p_proto,
 462                         snat_session_key_t * p_value,
 463                         u8 * p_dont_translate, void *d, void *e)
 464 {
 465   icmp46_header_t *icmp0;
 466   u32 sw_if_index0;
 467   u32 rx_fib_index0;
 468   snat_session_key_t key0;
 469   snat_session_t *s0 = 0;
 470   u8 dont_translate = 0;
 471   clib_bihash_kv_8_8_t kv0, value0;
 472   u32 next0 = ~0;
 473   int err;
 474
 475   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 476   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 477   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 478
 479   err = icmp_get_key (ip0, &key0);
 480   if (err != -1)
 481     {
 482       b0->error = node->errors[err];
 483       next0 = SNAT_IN2OUT_NEXT_DROP;
 484       goto out;
 485     }
 486   key0.fib_index = rx_fib_index0;
 487
 488   kv0.key = key0.as_u64;
 489
 490   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].in2out, &kv0,
 491                               &value0))
 492     {
 493       if (vnet_buffer (b0)->sw_if_index[VLIB_TX] != ~0)
 494         {
 495           if (PREDICT_FALSE (nat_not_translate_output_feature (sm, ip0,
 496                                                                key0.protocol,
 497                                                                key0.port,
 498                                                                key0.port,
 499                                                                thread_index,
 500                                                                sw_if_index0)))
 501             {
 502               dont_translate = 1;
 503               goto out;
 504             }
 505         }
 506       else
 507         {
 508           if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
 509                                                  ip0, SNAT_PROTOCOL_ICMP,
 510                                                  rx_fib_index0,
 511                                                  thread_index)))
 512             {
 513               dont_translate = 1;
 514               goto out;
 515             }
 516         }
 517
 518       if (PREDICT_FALSE (icmp_is_error_message (icmp0)))
 519         {
 520           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 521           next0 = SNAT_IN2OUT_NEXT_DROP;
 522           goto out;
 523         }
 524
 525       next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0,
 526                          thread_index, vlib_time_now (sm->vlib_main));
 527
 528       if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
 529         goto out;
 530
 531       if (!s0)
 532         {
 533           dont_translate = 1;
 534           goto out;
 535         }
 536     }
 537   else
 538     {
 539       if (PREDICT_FALSE (icmp0->type != ICMP4_echo_request &&
 540                          icmp0->type != ICMP4_echo_reply &&
 541                          !icmp_is_error_message (icmp0)))
 542         {
 543           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 544           next0 = SNAT_IN2OUT_NEXT_DROP;
 545           goto out;
 546         }
 547
 548       s0 = pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
 549                               value0.value);
 550     }
 551
 552 out:
 553   *p_proto = key0.protocol;
 554   if (s0)
 555     *p_value = s0->out2in;
 556   *p_dont_translate = dont_translate;
 557   if (d)
 558     *(snat_session_t **) d = s0;
 559   return next0;
 560 }
 561 #endif
 562
 563 #ifndef CLIB_MARCH_VARIANT
 564 /**
 565  * Get address and port values to be used for ICMP packet translation
 566  *
 567  * @param[in] sm                 NAT main
 568  * @param[in,out] node           NAT node runtime
 569  * @param[in] thread_index       thread index
 570  * @param[in,out] b0             buffer containing packet to be translated
 571  * @param[out] p_proto           protocol used for matching
 572  * @param[out] p_value           address and port after NAT translation
 573  * @param[out] p_dont_translate  if packet should not be translated
 574  * @param d                      optional parameter
 575  * @param e                      optional parameter
 576  */
 577 u32
 578 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
 579                         u32 thread_index, vlib_buffer_t * b0,
 580                         ip4_header_t * ip0, u8 * p_proto,
 581                         snat_session_key_t * p_value,
 582                         u8 * p_dont_translate, void *d, void *e)
 583 {
 584   icmp46_header_t *icmp0;
 585   u32 sw_if_index0;
 586   u32 rx_fib_index0;
 587   snat_session_key_t key0;
 588   snat_session_key_t sm0;
 589   u8 dont_translate = 0;
 590   u8 is_addr_only;
 591   u32 next0 = ~0;
 592   int err;
 593
 594   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 595   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 596   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 597
 598   err = icmp_get_key (ip0, &key0);
 599   if (err != -1)
 600     {
 601       b0->error = node->errors[err];
 602       next0 = SNAT_IN2OUT_NEXT_DROP;
 603       goto out2;
 604     }
 605   key0.fib_index = rx_fib_index0;
 606
 607   if (snat_static_mapping_match
 608       (sm, key0, &sm0, 0, &is_addr_only, 0, 0, 0, 0))
 609     {
 610       if (PREDICT_FALSE (snat_not_translate_fast (sm, node, sw_if_index0, ip0,
 611                                                   IP_PROTOCOL_ICMP,
 612                                                   rx_fib_index0)))
 613         {
 614           dont_translate = 1;
 615           goto out;
 616         }
 617
 618       if (icmp_is_error_message (icmp0))
 619         {
 620           next0 = SNAT_IN2OUT_NEXT_DROP;
 621           goto out;
 622         }
 623
 624       b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
 625       next0 = SNAT_IN2OUT_NEXT_DROP;
 626       goto out;
 627     }
 628
 629   if (PREDICT_FALSE (icmp0->type != ICMP4_echo_request &&
 630                      (icmp0->type != ICMP4_echo_reply || !is_addr_only) &&
 631                      !icmp_is_error_message (icmp0)))
 632     {
 633       b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 634       next0 = SNAT_IN2OUT_NEXT_DROP;
 635       goto out;
 636     }
 637
 638 out:
 639   *p_value = sm0;
 640 out2:
 641   *p_proto = key0.protocol;
 642   *p_dont_translate = dont_translate;
 643   return next0;
 644 }
 645 #endif
 646
 647 #ifndef CLIB_MARCH_VARIANT
 648 u32
 649 icmp_in2out (snat_main_t * sm,
 650              vlib_buffer_t * b0,
 651              ip4_header_t * ip0,
 652              icmp46_header_t * icmp0,
 653              u32 sw_if_index0,
 654              u32 rx_fib_index0,
 655              vlib_node_runtime_t * node,
 656              u32 next0, u32 thread_index, void *d, void *e)
 657 {
 658   snat_session_key_t sm0;
 659   u8 protocol;
 660   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 661   ip4_header_t *inner_ip0;
 662   void *l4_header = 0;
 663   icmp46_header_t *inner_icmp0;
 664   u8 dont_translate;
 665   u32 new_addr0, old_addr0;
 666   u16 old_id0, new_id0;
 667   u16 old_checksum0, new_checksum0;
 668   ip_csum_t sum0;
 669   u16 checksum0;
 670   u32 next0_tmp;
 671
 672   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 673
 674   next0_tmp = sm->icmp_match_in2out_cb (sm, node, thread_index, b0, ip0,
 675                                         &protocol, &sm0, &dont_translate, d,
 676                                         e);
 677   if (next0_tmp != ~0)
 678     next0 = next0_tmp;
 679   if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
 680     goto out;
 681
 682   if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
 683     {
 684       sum0 = ip_incremental_checksum_buffer (sm->vlib_main, b0, (u8 *) icmp0 -
 685                                              (u8 *)
 686                                              vlib_buffer_get_current (b0),
 687                                              ntohs (ip0->length) -
 688                                              ip4_header_bytes (ip0), 0);
 689       checksum0 = ~ip_csum_fold (sum0);
 690       if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff))
 691         {
 692           next0 = SNAT_IN2OUT_NEXT_DROP;
 693           goto out;
 694         }
 695     }
 696
 697   old_addr0 = ip0->src_address.as_u32;
 698   new_addr0 = ip0->src_address.as_u32 = sm0.addr.as_u32;
 699
 700   sum0 = ip0->checksum;
 701   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 702                          src_address /* changed member */ );
 703   ip0->checksum = ip_csum_fold (sum0);
 704
 705   if (icmp0->checksum == 0)
 706     icmp0->checksum = 0xffff;
 707
 708   if (!icmp_is_error_message (icmp0))
 709     {
 710       new_id0 = sm0.port;
 711       if (PREDICT_FALSE (new_id0 != echo0->identifier))
 712         {
 713           old_id0 = echo0->identifier;
 714           new_id0 = sm0.port;
 715           echo0->identifier = new_id0;
 716
 717           sum0 = icmp0->checksum;
 718           sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 719                                  identifier);
 720           icmp0->checksum = ip_csum_fold (sum0);
 721         }
 722     }
 723   else
 724     {
 725       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 726       l4_header = ip4_next_header (inner_ip0);
 727
 728       if (!ip4_header_checksum_is_valid (inner_ip0))
 729         {
 730           next0 = SNAT_IN2OUT_NEXT_DROP;
 731           goto out;
 732         }
 733
 734       /* update inner destination IP address */
 735       old_addr0 = inner_ip0->dst_address.as_u32;
 736       inner_ip0->dst_address = sm0.addr;
 737       new_addr0 = inner_ip0->dst_address.as_u32;
 738       sum0 = icmp0->checksum;
 739       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 740                              dst_address /* changed member */ );
 741       icmp0->checksum = ip_csum_fold (sum0);
 742
 743       /* update inner IP header checksum */
 744       old_checksum0 = inner_ip0->checksum;
 745       sum0 = inner_ip0->checksum;
 746       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 747                              dst_address /* changed member */ );
 748       inner_ip0->checksum = ip_csum_fold (sum0);
 749       new_checksum0 = inner_ip0->checksum;
 750       sum0 = icmp0->checksum;
 751       sum0 = ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
 752                              checksum);
 753       icmp0->checksum = ip_csum_fold (sum0);
 754
 755       switch (protocol)
 756         {
 757         case SNAT_PROTOCOL_ICMP:
 758           inner_icmp0 = (icmp46_header_t *) l4_header;
 759           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 760
 761           old_id0 = inner_echo0->identifier;
 762           new_id0 = sm0.port;
 763           inner_echo0->identifier = new_id0;
 764
 765           sum0 = icmp0->checksum;
 766           sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 767                                  identifier);
 768           icmp0->checksum = ip_csum_fold (sum0);
 769           break;
 770         case SNAT_PROTOCOL_UDP:
 771         case SNAT_PROTOCOL_TCP:
 772           old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
 773           new_id0 = sm0.port;
 774           ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
 775
 776           sum0 = icmp0->checksum;
 777           sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
 778                                  dst_port);
 779           icmp0->checksum = ip_csum_fold (sum0);
 780           break;
 781         default:
 782           ASSERT (0);
 783         }
 784     }
 785
 786   if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
 787     {
 788       if (sm->deterministic ||
 789           0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
 790                                       sm->endpoint_dependent))
 791         vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
 792     }
 793
 794 out:
 795   return next0;
 796 }
 797 #endif
 798
 799 static inline u32
 800 icmp_in2out_slow_path (snat_main_t * sm,
 801                        vlib_buffer_t * b0,
 802                        ip4_header_t * ip0,
 803                        icmp46_header_t * icmp0,
 804                        u32 sw_if_index0,
 805                        u32 rx_fib_index0,
 806                        vlib_node_runtime_t * node,
 807                        u32 next0,
 808                        f64 now, u32 thread_index, snat_session_t ** p_s0)
 809 {
 810   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 811                        next0, thread_index, p_s0, 0);
 812   snat_session_t *s0 = *p_s0;
 813   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
 814     {
 815       /* Accounting */
 816       nat44_session_update_counters (s0, now,
 817                                      vlib_buffer_length_in_chain
 818                                      (sm->vlib_main, b0), thread_index);
 819       /* Per-user LRU list maintenance */
 820       nat44_session_update_lru (sm, s0, thread_index);
 821     }
 822   return next0;
 823 }
 824
 825 static int
 826 nat_in2out_sm_unknown_proto (snat_main_t * sm,
 827                              vlib_buffer_t * b,
 828                              ip4_header_t * ip, u32 rx_fib_index)
 829 {
 830   clib_bihash_kv_8_8_t kv, value;
 831   snat_static_mapping_t *m;
 832   snat_session_key_t m_key;
 833   u32 old_addr, new_addr;
 834   ip_csum_t sum;
 835
 836   m_key.addr = ip->src_address;
 837   m_key.port = 0;
 838   m_key.protocol = 0;
 839   m_key.fib_index = rx_fib_index;
 840   kv.key = m_key.as_u64;
 841   if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 842     return 1;
 843
 844   m = pool_elt_at_index (sm->static_mappings, value.value);
 845
 846   old_addr = ip->src_address.as_u32;
 847   new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 848   sum = ip->checksum;
 849   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 850   ip->checksum = ip_csum_fold (sum);
 851
 852
 853   /* Hairpinning */
 854   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 855     {
 856       vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 857       nat_hairpinning_sm_unknown_proto (sm, b, ip);
 858     }
 859
 860   return 0;
 861 }
 862
 863 static inline uword
 864 snat_in2out_node_fn_inline (vlib_main_t * vm,
 865                             vlib_node_runtime_t * node,
 866                             vlib_frame_t * frame, int is_slow_path,
 867                             int is_output_feature)
 868 {
 869   u32 n_left_from, *from, *to_next;
 870   snat_in2out_next_t next_index;
 871   u32 pkts_processed = 0;
 872   snat_main_t *sm = &snat_main;
 873   f64 now = vlib_time_now (vm);
 874   u32 stats_node_index;
 875   u32 thread_index = vm->thread_index;
 876   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 877     0, fragments = 0;
 878
 879   stats_node_index = is_slow_path ? sm->in2out_slowpath_node_index :
 880     sm->in2out_node_index;
 881
 882   from = vlib_frame_vector_args (frame);
 883   n_left_from = frame->n_vectors;
 884   next_index = node->cached_next_index;
 885
 886   while (n_left_from > 0)
 887     {
 888       u32 n_left_to_next;
 889
 890       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 891
 892       while (n_left_from >= 4 && n_left_to_next >= 2)
 893         {
 894           u32 bi0, bi1;
 895           vlib_buffer_t *b0, *b1;
 896           u32 next0, next1;
 897           u32 sw_if_index0, sw_if_index1;
 898           ip4_header_t *ip0, *ip1;
 899           ip_csum_t sum0, sum1;
 900           u32 new_addr0, old_addr0, new_addr1, old_addr1;
 901           u16 old_port0, new_port0, old_port1, new_port1;
 902           udp_header_t *udp0, *udp1;
 903           tcp_header_t *tcp0, *tcp1;
 904           icmp46_header_t *icmp0, *icmp1;
 905           snat_session_key_t key0, key1;
 906           u32 rx_fib_index0, rx_fib_index1;
 907           u32 proto0, proto1;
 908           snat_session_t *s0 = 0, *s1 = 0;
 909           clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
 910           u32 iph_offset0 = 0, iph_offset1 = 0;
 911
 912           /* Prefetch next iteration. */
 913           {
 914             vlib_buffer_t *p2, *p3;
 915
 916             p2 = vlib_get_buffer (vm, from[2]);
 917             p3 = vlib_get_buffer (vm, from[3]);
 918
 919             vlib_prefetch_buffer_header (p2, LOAD);
 920             vlib_prefetch_buffer_header (p3, LOAD);
 921
 922             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 923             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 924           }
 925
 926           /* speculatively enqueue b0 and b1 to the current next frame */
 927           to_next[0] = bi0 = from[0];
 928           to_next[1] = bi1 = from[1];
 929           from += 2;
 930           to_next += 2;
 931           n_left_from -= 2;
 932           n_left_to_next -= 2;
 933
 934           b0 = vlib_get_buffer (vm, bi0);
 935           b1 = vlib_get_buffer (vm, bi1);
 936
 937           if (is_output_feature)
 938             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
 939
 940           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 941                                   iph_offset0);
 942
 943           udp0 = ip4_next_header (ip0);
 944           tcp0 = (tcp_header_t *) udp0;
 945           icmp0 = (icmp46_header_t *) udp0;
 946
 947           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 948           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 949                                    sw_if_index0);
 950
 951           next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
 952
 953           if (PREDICT_FALSE (ip0->ttl == 1))
 954             {
 955               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 956               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 957                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 958                                            0);
 959               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
 960               goto trace00;
 961             }
 962
 963           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 964
 965           /* Next configured feature, probably ip4-lookup */
 966           if (is_slow_path)
 967             {
 968               if (PREDICT_FALSE (proto0 == ~0))
 969                 {
 970                   if (nat_in2out_sm_unknown_proto
 971                       (sm, b0, ip0, rx_fib_index0))
 972                     {
 973                       next0 = SNAT_IN2OUT_NEXT_DROP;
 974                       b0->error =
 975                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
 976                     }
 977                   other_packets++;
 978                   goto trace00;
 979                 }
 980
 981               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 982                 {
 983                   next0 = icmp_in2out_slow_path
 984                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
 985                      node, next0, now, thread_index, &s0);
 986                   icmp_packets++;
 987                   goto trace00;
 988                 }
 989             }
 990           else
 991             {
 992               if (PREDICT_FALSE (proto0 == ~0))
 993                 {
 994                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 995                   goto trace00;
 996                 }
 997
 998               if (ip4_is_fragment (ip0))
 999                 {
1000                   next0 = SNAT_IN2OUT_NEXT_REASS;
1001                   fragments++;
1002                   goto trace00;
1003                 }
1004
1005               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1006                 {
1007                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1008                   goto trace00;
1009                 }
1010             }
1011
1012           key0.addr = ip0->src_address;
1013           key0.port = udp0->src_port;
1014           key0.protocol = proto0;
1015           key0.fib_index = rx_fib_index0;
1016
1017           kv0.key = key0.as_u64;
1018
1019           if (PREDICT_FALSE
1020               (clib_bihash_search_8_8
1021                (&sm->per_thread_data[thread_index].in2out, &kv0,
1022                 &value0) != 0))
1023             {
1024               if (is_slow_path)
1025                 {
1026                   if (is_output_feature)
1027                     {
1028                       if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1029                                                                            ip0,
1030                                                                            proto0,
1031                                                                            udp0->src_port,
1032                                                                            udp0->dst_port,
1033                                                                            thread_index,
1034                                                                            sw_if_index0)))
1035                         goto trace00;
1036
1037                       /*
1038                        * Send DHCP packets to the ipv4 stack, or we won't
1039                        * be able to use dhcp client on the outside interface
1040                        */
1041                       if (PREDICT_FALSE
1042                           ((b0->flags & VNET_BUFFER_F_LOCALLY_ORIGINATED)
1043                            && proto0 == SNAT_PROTOCOL_UDP
1044                            && (udp0->dst_port ==
1045                                clib_host_to_net_u16
1046                                (UDP_DST_PORT_dhcp_to_server))))
1047                         goto trace00;
1048                     }
1049                   else
1050                     {
1051                       if (PREDICT_FALSE
1052                           (snat_not_translate
1053                            (sm, node, sw_if_index0, ip0, proto0,
1054                             rx_fib_index0, thread_index)))
1055                         goto trace00;
1056                     }
1057
1058                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1059                                      &s0, node, next0, thread_index, now);
1060                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1061                     goto trace00;
1062
1063                   if (PREDICT_FALSE (!s0))
1064                     goto trace00;
1065                 }
1066               else
1067                 {
1068                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1069                   goto trace00;
1070                 }
1071             }
1072           else
1073             s0 =
1074               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1075                                  value0.value);
1076
1077           b0->flags |= VNET_BUFFER_F_IS_NATED;
1078
1079           old_addr0 = ip0->src_address.as_u32;
1080           ip0->src_address = s0->out2in.addr;
1081           new_addr0 = ip0->src_address.as_u32;
1082           if (!is_output_feature)
1083             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1084
1085           sum0 = ip0->checksum;
1086           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1087                                  ip4_header_t,
1088                                  src_address /* changed member */ );
1089           ip0->checksum = ip_csum_fold (sum0);
1090
1091           old_port0 = udp0->src_port;
1092           new_port0 = udp0->src_port = s0->out2in.port;
1093
1094           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1095             {
1096               sum0 = tcp0->checksum;
1097               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1098                                      ip4_header_t,
1099                                      dst_address /* changed member */ );
1100               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1101                                      ip4_header_t /* cheat */ ,
1102                                      length /* changed member */ );
1103               mss_clamping (sm, tcp0, &sum0);
1104               tcp0->checksum = ip_csum_fold (sum0);
1105               tcp_packets++;
1106             }
1107           else
1108             {
1109               if (PREDICT_FALSE (udp0->checksum))
1110                 {
1111                   sum0 = udp0->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                   udp0->checksum = ip_csum_fold (sum0);
1119                 }
1120               udp_packets++;
1121             }
1122
1123           /* Accounting */
1124           nat44_session_update_counters (s0, now,
1125                                          vlib_buffer_length_in_chain (vm, b0),
1126                                          thread_index);
1127           /* Per-user LRU list maintenance */
1128           nat44_session_update_lru (sm, s0, thread_index);
1129         trace00:
1130
1131           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1132                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1133             {
1134               snat_in2out_trace_t *t =
1135                 vlib_add_trace (vm, node, b0, sizeof (*t));
1136               t->is_slow_path = is_slow_path;
1137               t->sw_if_index = sw_if_index0;
1138               t->next_index = next0;
1139               t->session_index = ~0;
1140               if (s0)
1141                 t->session_index =
1142                   s0 - sm->per_thread_data[thread_index].sessions;
1143             }
1144
1145           pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1146
1147           if (is_output_feature)
1148             iph_offset1 = vnet_buffer (b1)->ip.save_rewrite_length;
1149
1150           ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1151                                   iph_offset1);
1152
1153           udp1 = ip4_next_header (ip1);
1154           tcp1 = (tcp_header_t *) udp1;
1155           icmp1 = (icmp46_header_t *) udp1;
1156
1157           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1158           rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1159                                    sw_if_index1);
1160
1161           if (PREDICT_FALSE (ip1->ttl == 1))
1162             {
1163               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1164               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1165                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1166                                            0);
1167               next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1168               goto trace01;
1169             }
1170
1171           proto1 = ip_proto_to_snat_proto (ip1->protocol);
1172
1173           /* Next configured feature, probably ip4-lookup */
1174           if (is_slow_path)
1175             {
1176               if (PREDICT_FALSE (proto1 == ~0))
1177                 {
1178                   if (nat_in2out_sm_unknown_proto
1179                       (sm, b1, ip1, rx_fib_index1))
1180                     {
1181                       next1 = SNAT_IN2OUT_NEXT_DROP;
1182                       b1->error =
1183                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1184                     }
1185                   other_packets++;
1186                   goto trace01;
1187                 }
1188
1189               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1190                 {
1191                   next1 = icmp_in2out_slow_path
1192                     (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1193                      next1, now, thread_index, &s1);
1194                   icmp_packets++;
1195                   goto trace01;
1196                 }
1197             }
1198           else
1199             {
1200               if (PREDICT_FALSE (proto1 == ~0))
1201                 {
1202                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1203                   goto trace01;
1204                 }
1205
1206               if (ip4_is_fragment (ip1))
1207                 {
1208                   next1 = SNAT_IN2OUT_NEXT_REASS;
1209                   fragments++;
1210                   goto trace01;
1211                 }
1212
1213               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1214                 {
1215                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1216                   goto trace01;
1217                 }
1218             }
1219
1220           key1.addr = ip1->src_address;
1221           key1.port = udp1->src_port;
1222           key1.protocol = proto1;
1223           key1.fib_index = rx_fib_index1;
1224
1225           kv1.key = key1.as_u64;
1226
1227           if (PREDICT_FALSE
1228               (clib_bihash_search_8_8
1229                (&sm->per_thread_data[thread_index].in2out, &kv1,
1230                 &value1) != 0))
1231             {
1232               if (is_slow_path)
1233                 {
1234                   if (is_output_feature)
1235                     {
1236                       if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1237                                                                            ip1,
1238                                                                            proto1,
1239                                                                            udp1->src_port,
1240                                                                            udp1->dst_port,
1241                                                                            thread_index,
1242                                                                            sw_if_index1)))
1243                         goto trace01;
1244
1245                       /*
1246                        * Send DHCP packets to the ipv4 stack, or we won't
1247                        * be able to use dhcp client on the outside interface
1248                        */
1249                       if (PREDICT_FALSE
1250                           ((b1->flags & VNET_BUFFER_F_LOCALLY_ORIGINATED)
1251                            && proto1 == SNAT_PROTOCOL_UDP
1252                            && (udp1->dst_port ==
1253                                clib_host_to_net_u16
1254                                (UDP_DST_PORT_dhcp_to_server))))
1255                         goto trace01;
1256                     }
1257                   else
1258                     {
1259                       if (PREDICT_FALSE
1260                           (snat_not_translate
1261                            (sm, node, sw_if_index1, ip1, proto1,
1262                             rx_fib_index1, thread_index)))
1263                         goto trace01;
1264                     }
1265
1266                   next1 = slow_path (sm, b1, ip1, rx_fib_index1, &key1,
1267                                      &s1, node, next1, thread_index, now);
1268                   if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1269                     goto trace01;
1270
1271                   if (PREDICT_FALSE (!s1))
1272                     goto trace01;
1273                 }
1274               else
1275                 {
1276                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1277                   goto trace01;
1278                 }
1279             }
1280           else
1281             s1 =
1282               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1283                                  value1.value);
1284
1285           b1->flags |= VNET_BUFFER_F_IS_NATED;
1286
1287           old_addr1 = ip1->src_address.as_u32;
1288           ip1->src_address = s1->out2in.addr;
1289           new_addr1 = ip1->src_address.as_u32;
1290           if (!is_output_feature)
1291             vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1292
1293           sum1 = ip1->checksum;
1294           sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1295                                  ip4_header_t,
1296                                  src_address /* changed member */ );
1297           ip1->checksum = ip_csum_fold (sum1);
1298
1299           old_port1 = udp1->src_port;
1300           new_port1 = udp1->src_port = s1->out2in.port;
1301
1302           if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1303             {
1304               sum1 = tcp1->checksum;
1305               sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1306                                      ip4_header_t,
1307                                      dst_address /* changed member */ );
1308               sum1 = ip_csum_update (sum1, old_port1, new_port1,
1309                                      ip4_header_t /* cheat */ ,
1310                                      length /* changed member */ );
1311               mss_clamping (sm, tcp1, &sum1);
1312               tcp1->checksum = ip_csum_fold (sum1);
1313               tcp_packets++;
1314             }
1315           else
1316             {
1317               if (PREDICT_FALSE (udp1->checksum))
1318                 {
1319                   sum1 = udp1->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                   udp1->checksum = ip_csum_fold (sum1);
1327                 }
1328               udp_packets++;
1329             }
1330
1331           /* Accounting */
1332           nat44_session_update_counters (s1, now,
1333                                          vlib_buffer_length_in_chain (vm, b1),
1334                                          thread_index);
1335           /* Per-user LRU list maintenance */
1336           nat44_session_update_lru (sm, s1, thread_index);
1337         trace01:
1338
1339           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1340                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1341             {
1342               snat_in2out_trace_t *t =
1343                 vlib_add_trace (vm, node, b1, sizeof (*t));
1344               t->sw_if_index = sw_if_index1;
1345               t->next_index = next1;
1346               t->session_index = ~0;
1347               if (s1)
1348                 t->session_index =
1349                   s1 - sm->per_thread_data[thread_index].sessions;
1350             }
1351
1352           pkts_processed += next1 == SNAT_IN2OUT_NEXT_LOOKUP;
1353
1354           /* verify speculative enqueues, maybe switch current next frame */
1355           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1356                                            to_next, n_left_to_next,
1357                                            bi0, bi1, next0, next1);
1358         }
1359
1360       while (n_left_from > 0 && n_left_to_next > 0)
1361         {
1362           u32 bi0;
1363           vlib_buffer_t *b0;
1364           u32 next0;
1365           u32 sw_if_index0;
1366           ip4_header_t *ip0;
1367           ip_csum_t sum0;
1368           u32 new_addr0, old_addr0;
1369           u16 old_port0, new_port0;
1370           udp_header_t *udp0;
1371           tcp_header_t *tcp0;
1372           icmp46_header_t *icmp0;
1373           snat_session_key_t key0;
1374           u32 rx_fib_index0;
1375           u32 proto0;
1376           snat_session_t *s0 = 0;
1377           clib_bihash_kv_8_8_t kv0, value0;
1378           u32 iph_offset0 = 0;
1379
1380           /* speculatively enqueue b0 to the current next frame */
1381           bi0 = from[0];
1382           to_next[0] = bi0;
1383           from += 1;
1384           to_next += 1;
1385           n_left_from -= 1;
1386           n_left_to_next -= 1;
1387
1388           b0 = vlib_get_buffer (vm, bi0);
1389           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1390
1391           if (is_output_feature)
1392             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
1393
1394           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1395                                   iph_offset0);
1396
1397           udp0 = ip4_next_header (ip0);
1398           tcp0 = (tcp_header_t *) udp0;
1399           icmp0 = (icmp46_header_t *) udp0;
1400
1401           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1402           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1403                                    sw_if_index0);
1404
1405           if (PREDICT_FALSE (ip0->ttl == 1))
1406             {
1407               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1408               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1409                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1410                                            0);
1411               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1412               goto trace0;
1413             }
1414
1415           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1416
1417           /* Next configured feature, probably ip4-lookup */
1418           if (is_slow_path)
1419             {
1420               if (PREDICT_FALSE (proto0 == ~0))
1421                 {
1422                   if (nat_in2out_sm_unknown_proto
1423                       (sm, b0, ip0, rx_fib_index0))
1424                     {
1425                       next0 = SNAT_IN2OUT_NEXT_DROP;
1426                       b0->error =
1427                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1428                     }
1429                   other_packets++;
1430                   goto trace0;
1431                 }
1432
1433               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1434                 {
1435                   next0 = icmp_in2out_slow_path
1436                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1437                      next0, now, thread_index, &s0);
1438                   icmp_packets++;
1439                   goto trace0;
1440                 }
1441             }
1442           else
1443             {
1444               if (PREDICT_FALSE (proto0 == ~0))
1445                 {
1446                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1447                   goto trace0;
1448                 }
1449
1450               if (ip4_is_fragment (ip0))
1451                 {
1452                   next0 = SNAT_IN2OUT_NEXT_REASS;
1453                   fragments++;
1454                   goto trace0;
1455                 }
1456
1457               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1458                 {
1459                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1460                   goto trace0;
1461                 }
1462             }
1463
1464           key0.addr = ip0->src_address;
1465           key0.port = udp0->src_port;
1466           key0.protocol = proto0;
1467           key0.fib_index = rx_fib_index0;
1468
1469           kv0.key = key0.as_u64;
1470
1471           if (clib_bihash_search_8_8
1472               (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1473             {
1474               if (is_slow_path)
1475                 {
1476                   if (is_output_feature)
1477                     {
1478                       if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1479                                                                            ip0,
1480                                                                            proto0,
1481                                                                            udp0->src_port,
1482                                                                            udp0->dst_port,
1483                                                                            thread_index,
1484                                                                            sw_if_index0)))
1485                         goto trace0;
1486
1487                       /*
1488                        * Send DHCP packets to the ipv4 stack, or we won't
1489                        * be able to use dhcp client on the outside interface
1490                        */
1491                       if (PREDICT_FALSE
1492                           ((b0->flags & VNET_BUFFER_F_LOCALLY_ORIGINATED)
1493                            && proto0 == SNAT_PROTOCOL_UDP
1494                            && (udp0->dst_port ==
1495                                clib_host_to_net_u16
1496                                (UDP_DST_PORT_dhcp_to_server))))
1497                         goto trace0;
1498                     }
1499                   else
1500                     {
1501                       if (PREDICT_FALSE
1502                           (snat_not_translate
1503                            (sm, node, sw_if_index0, ip0, proto0,
1504                             rx_fib_index0, thread_index)))
1505                         goto trace0;
1506                     }
1507
1508                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1509                                      &s0, node, next0, thread_index, now);
1510
1511                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1512                     goto trace0;
1513
1514                   if (PREDICT_FALSE (!s0))
1515                     goto trace0;
1516                 }
1517               else
1518                 {
1519                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1520                   goto trace0;
1521                 }
1522             }
1523           else
1524             s0 =
1525               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1526                                  value0.value);
1527
1528           b0->flags |= VNET_BUFFER_F_IS_NATED;
1529
1530           old_addr0 = ip0->src_address.as_u32;
1531           ip0->src_address = s0->out2in.addr;
1532           new_addr0 = ip0->src_address.as_u32;
1533           if (!is_output_feature)
1534             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1535
1536           sum0 = ip0->checksum;
1537           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1538                                  ip4_header_t,
1539                                  src_address /* changed member */ );
1540           ip0->checksum = ip_csum_fold (sum0);
1541
1542           old_port0 = udp0->src_port;
1543           new_port0 = udp0->src_port = s0->out2in.port;
1544
1545           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1546             {
1547               sum0 = tcp0->checksum;
1548               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1549                                      ip4_header_t,
1550                                      dst_address /* changed member */ );
1551               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1552                                      ip4_header_t /* cheat */ ,
1553                                      length /* changed member */ );
1554               mss_clamping (sm, tcp0, &sum0);
1555               tcp0->checksum = ip_csum_fold (sum0);
1556               tcp_packets++;
1557             }
1558           else
1559             {
1560               if (PREDICT_FALSE (udp0->checksum))
1561                 {
1562                   sum0 = udp0->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                   udp0->checksum = ip_csum_fold (sum0);
1570                 }
1571               udp_packets++;
1572             }
1573
1574           /* Accounting */
1575           nat44_session_update_counters (s0, now,
1576                                          vlib_buffer_length_in_chain (vm, b0),
1577                                          thread_index);
1578           /* Per-user LRU list maintenance */
1579           nat44_session_update_lru (sm, s0, thread_index);
1580
1581         trace0:
1582           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1583                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1584             {
1585               snat_in2out_trace_t *t =
1586                 vlib_add_trace (vm, node, b0, sizeof (*t));
1587               t->is_slow_path = is_slow_path;
1588               t->sw_if_index = sw_if_index0;
1589               t->next_index = next0;
1590               t->session_index = ~0;
1591               if (s0)
1592                 t->session_index =
1593                   s0 - sm->per_thread_data[thread_index].sessions;
1594             }
1595
1596           pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1597
1598           /* verify speculative enqueue, maybe switch current next frame */
1599           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1600                                            to_next, n_left_to_next,
1601                                            bi0, next0);
1602         }
1603
1604       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1605     }
1606
1607   vlib_node_increment_counter (vm, stats_node_index,
1608                                SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
1609                                pkts_processed);
1610   vlib_node_increment_counter (vm, stats_node_index,
1611                                SNAT_IN2OUT_ERROR_TCP_PACKETS, tcp_packets);
1612   vlib_node_increment_counter (vm, stats_node_index,
1613                                SNAT_IN2OUT_ERROR_UDP_PACKETS, udp_packets);
1614   vlib_node_increment_counter (vm, stats_node_index,
1615                                SNAT_IN2OUT_ERROR_ICMP_PACKETS, icmp_packets);
1616   vlib_node_increment_counter (vm, stats_node_index,
1617                                SNAT_IN2OUT_ERROR_OTHER_PACKETS,
1618                                other_packets);
1619   vlib_node_increment_counter (vm, stats_node_index,
1620                                SNAT_IN2OUT_ERROR_FRAGMENTS, fragments);
1621
1622   return frame->n_vectors;
1623 }
1624
1625 VLIB_NODE_FN (snat_in2out_node) (vlib_main_t * vm,
1626                                  vlib_node_runtime_t * node,
1627                                  vlib_frame_t * frame)
1628 {
1629   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1630                                      0);
1631 }
1632
1633 /* *INDENT-OFF* */
1634 VLIB_REGISTER_NODE (snat_in2out_node) = {
1635   .name = "nat44-in2out",
1636   .vector_size = sizeof (u32),
1637   .format_trace = format_snat_in2out_trace,
1638   .type = VLIB_NODE_TYPE_INTERNAL,
1639
1640   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1641   .error_strings = snat_in2out_error_strings,
1642
1643   .runtime_data_bytes = sizeof (snat_runtime_t),
1644
1645   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1646
1647   /* edit / add dispositions here */
1648   .next_nodes = {
1649     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1650     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1651     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1652     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1653     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1654   },
1655 };
1656 /* *INDENT-ON* */
1657
1658 VLIB_NODE_FN (snat_in2out_output_node) (vlib_main_t * vm,
1659                                         vlib_node_runtime_t * node,
1660                                         vlib_frame_t * frame)
1661 {
1662   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1663                                      1);
1664 }
1665
1666 /* *INDENT-OFF* */
1667 VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1668   .name = "nat44-in2out-output",
1669   .vector_size = sizeof (u32),
1670   .format_trace = format_snat_in2out_trace,
1671   .type = VLIB_NODE_TYPE_INTERNAL,
1672
1673   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1674   .error_strings = snat_in2out_error_strings,
1675
1676   .runtime_data_bytes = sizeof (snat_runtime_t),
1677
1678   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1679
1680   /* edit / add dispositions here */
1681   .next_nodes = {
1682     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1683     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1684     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1685     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1686     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1687   },
1688 };
1689 /* *INDENT-ON* */
1690
1691 VLIB_NODE_FN (snat_in2out_slowpath_node) (vlib_main_t * vm,
1692                                           vlib_node_runtime_t * node,
1693                                           vlib_frame_t * frame)
1694 {
1695   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1696                                      0);
1697 }
1698
1699 /* *INDENT-OFF* */
1700 VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1701   .name = "nat44-in2out-slowpath",
1702   .vector_size = sizeof (u32),
1703   .format_trace = format_snat_in2out_trace,
1704   .type = VLIB_NODE_TYPE_INTERNAL,
1705
1706   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1707   .error_strings = snat_in2out_error_strings,
1708
1709   .runtime_data_bytes = sizeof (snat_runtime_t),
1710
1711   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1712
1713   /* edit / add dispositions here */
1714   .next_nodes = {
1715     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1716     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1717     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1718     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1719     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1720   },
1721 };
1722 /* *INDENT-ON* */
1723
1724 VLIB_NODE_FN (snat_in2out_output_slowpath_node) (vlib_main_t * vm,
1725                                                  vlib_node_runtime_t * node,
1726                                                  vlib_frame_t * frame)
1727 {
1728   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1729                                      1);
1730 }
1731
1732 /* *INDENT-OFF* */
1733 VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1734   .name = "nat44-in2out-output-slowpath",
1735   .vector_size = sizeof (u32),
1736   .format_trace = format_snat_in2out_trace,
1737   .type = VLIB_NODE_TYPE_INTERNAL,
1738
1739   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1740   .error_strings = snat_in2out_error_strings,
1741
1742   .runtime_data_bytes = sizeof (snat_runtime_t),
1743
1744   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1745
1746   /* edit / add dispositions here */
1747   .next_nodes = {
1748     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1749     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1750     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1751     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1752     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1753   },
1754 };
1755 /* *INDENT-ON* */
1756
1757 VLIB_NODE_FN (nat44_in2out_reass_node) (vlib_main_t * vm,
1758                                         vlib_node_runtime_t * node,
1759                                         vlib_frame_t * frame)
1760 {
1761   u32 n_left_from, *from, *to_next;
1762   snat_in2out_next_t next_index;
1763   u32 pkts_processed = 0, cached_fragments = 0;
1764   snat_main_t *sm = &snat_main;
1765   f64 now = vlib_time_now (vm);
1766   u32 thread_index = vm->thread_index;
1767   snat_main_per_thread_data_t *per_thread_data =
1768     &sm->per_thread_data[thread_index];
1769   u32 *fragments_to_drop = 0;
1770   u32 *fragments_to_loopback = 0;
1771
1772   from = vlib_frame_vector_args (frame);
1773   n_left_from = frame->n_vectors;
1774   next_index = node->cached_next_index;
1775
1776   while (n_left_from > 0)
1777     {
1778       u32 n_left_to_next;
1779
1780       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1781
1782       while (n_left_from > 0 && n_left_to_next > 0)
1783         {
1784           u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1785           vlib_buffer_t *b0;
1786           u32 next0;
1787           u8 cached0 = 0;
1788           ip4_header_t *ip0;
1789           nat_reass_ip4_t *reass0;
1790           udp_header_t *udp0;
1791           tcp_header_t *tcp0;
1792           icmp46_header_t *icmp0;
1793           snat_session_key_t key0;
1794           clib_bihash_kv_8_8_t kv0, value0;
1795           snat_session_t *s0 = 0;
1796           u16 old_port0, new_port0;
1797           ip_csum_t sum0;
1798
1799           /* speculatively enqueue b0 to the current next frame */
1800           bi0 = from[0];
1801           to_next[0] = bi0;
1802           from += 1;
1803           to_next += 1;
1804           n_left_from -= 1;
1805           n_left_to_next -= 1;
1806
1807           b0 = vlib_get_buffer (vm, bi0);
1808           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1809
1810           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1811           rx_fib_index0 =
1812             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1813                                                  sw_if_index0);
1814
1815           if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1816             {
1817               next0 = SNAT_IN2OUT_NEXT_DROP;
1818               b0->error = node->errors[SNAT_IN2OUT_ERROR_DROP_FRAGMENT];
1819               goto trace0;
1820             }
1821
1822           ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
1823           udp0 = ip4_next_header (ip0);
1824           tcp0 = (tcp_header_t *) udp0;
1825           icmp0 = (icmp46_header_t *) udp0;
1826           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1827
1828           reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1829                                                  ip0->dst_address,
1830                                                  ip0->fragment_id,
1831                                                  ip0->protocol,
1832                                                  1, &fragments_to_drop);
1833
1834           if (PREDICT_FALSE (!reass0))
1835             {
1836               next0 = SNAT_IN2OUT_NEXT_DROP;
1837               b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_REASS];
1838               nat_elog_notice ("maximum reassemblies exceeded");
1839               goto trace0;
1840             }
1841
1842           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1843             {
1844               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1845                 {
1846                   next0 = icmp_in2out_slow_path
1847                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1848                      next0, now, thread_index, &s0);
1849
1850                   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP))
1851                     {
1852                       if (s0)
1853                         reass0->sess_index = s0 - per_thread_data->sessions;
1854                       else
1855                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1856                       nat_ip4_reass_get_frags (reass0,
1857                                                &fragments_to_loopback);
1858                     }
1859
1860                   goto trace0;
1861                 }
1862
1863               key0.addr = ip0->src_address;
1864               key0.port = udp0->src_port;
1865               key0.protocol = proto0;
1866               key0.fib_index = rx_fib_index0;
1867               kv0.key = key0.as_u64;
1868
1869               if (clib_bihash_search_8_8
1870                   (&per_thread_data->in2out, &kv0, &value0))
1871                 {
1872                   if (PREDICT_FALSE
1873                       (snat_not_translate
1874                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1875                         thread_index)))
1876                     goto trace0;
1877
1878                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1879                                      &s0, node, next0, thread_index, now);
1880
1881                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1882                     goto trace0;
1883
1884                   if (PREDICT_FALSE (!s0))
1885                     goto trace0;
1886
1887                   reass0->sess_index = s0 - per_thread_data->sessions;
1888                 }
1889               else
1890                 {
1891                   s0 = pool_elt_at_index (per_thread_data->sessions,
1892                                           value0.value);
1893                   reass0->sess_index = value0.value;
1894                 }
1895               nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1896             }
1897           else
1898             {
1899               if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1900                 {
1901                   if (nat_ip4_reass_add_fragment
1902                       (thread_index, reass0, bi0, &fragments_to_drop))
1903                     {
1904                       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_FRAG];
1905                       nat_elog_notice
1906                         ("maximum fragments per reassembly exceeded");
1907                       next0 = SNAT_IN2OUT_NEXT_DROP;
1908                       goto trace0;
1909                     }
1910                   cached0 = 1;
1911                   goto trace0;
1912                 }
1913               s0 = pool_elt_at_index (per_thread_data->sessions,
1914                                       reass0->sess_index);
1915             }
1916
1917           old_addr0 = ip0->src_address.as_u32;
1918           ip0->src_address = s0->out2in.addr;
1919           new_addr0 = ip0->src_address.as_u32;
1920           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1921
1922           sum0 = ip0->checksum;
1923           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1924                                  ip4_header_t,
1925                                  src_address /* changed member */ );
1926           ip0->checksum = ip_csum_fold (sum0);
1927
1928           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1929             {
1930               old_port0 = udp0->src_port;
1931               new_port0 = udp0->src_port = s0->out2in.port;
1932
1933               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1934                 {
1935                   sum0 = tcp0->checksum;
1936                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1937                                          ip4_header_t,
1938                                          dst_address /* changed member */ );
1939                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1940                                          ip4_header_t /* cheat */ ,
1941                                          length /* changed member */ );
1942                   tcp0->checksum = ip_csum_fold (sum0);
1943                 }
1944               else if (PREDICT_FALSE (udp0->checksum))
1945                 {
1946                   sum0 = udp0->checksum;
1947                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1948                                          ip4_header_t,
1949                                          dst_address /* changed member */ );
1950                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1951                                          ip4_header_t /* cheat */ ,
1952                                          length /* changed member */ );
1953                   udp0->checksum = ip_csum_fold (sum0);
1954                 }
1955             }
1956
1957           /* Hairpinning */
1958           nat44_reass_hairpinning (sm, b0, ip0, s0->out2in.port,
1959                                    s0->ext_host_port, proto0, 0);
1960
1961           /* Accounting */
1962           nat44_session_update_counters (s0, now,
1963                                          vlib_buffer_length_in_chain (vm, b0),
1964                                          thread_index);
1965           /* Per-user LRU list maintenance */
1966           nat44_session_update_lru (sm, s0, thread_index);
1967
1968         trace0:
1969           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1970                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1971             {
1972               nat44_reass_trace_t *t =
1973                 vlib_add_trace (vm, node, b0, sizeof (*t));
1974               t->cached = cached0;
1975               t->sw_if_index = sw_if_index0;
1976               t->next_index = next0;
1977             }
1978
1979           if (cached0)
1980             {
1981               n_left_to_next++;
1982               to_next--;
1983               cached_fragments++;
1984             }
1985           else
1986             {
1987               pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
1988
1989               /* verify speculative enqueue, maybe switch current next frame */
1990               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1991                                                to_next, n_left_to_next,
1992                                                bi0, next0);
1993             }
1994
1995           if (n_left_from == 0 && vec_len (fragments_to_loopback))
1996             {
1997               from = vlib_frame_vector_args (frame);
1998               u32 len = vec_len (fragments_to_loopback);
1999               if (len <= VLIB_FRAME_SIZE)
2000                 {
2001                   clib_memcpy_fast (from, fragments_to_loopback,
2002                                     sizeof (u32) * len);
2003                   n_left_from = len;
2004                   vec_reset_length (fragments_to_loopback);
2005                 }
2006               else
2007                 {
2008                   clib_memcpy_fast (from, fragments_to_loopback +
2009                                     (len - VLIB_FRAME_SIZE),
2010                                     sizeof (u32) * VLIB_FRAME_SIZE);
2011                   n_left_from = VLIB_FRAME_SIZE;
2012                   _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
2013                 }
2014             }
2015         }
2016
2017       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2018     }
2019
2020   vlib_node_increment_counter (vm, sm->in2out_reass_node_index,
2021                                SNAT_IN2OUT_ERROR_PROCESSED_FRAGMENTS,
2022                                pkts_processed);
2023   vlib_node_increment_counter (vm, sm->in2out_reass_node_index,
2024                                SNAT_IN2OUT_ERROR_CACHED_FRAGMENTS,
2025                                cached_fragments);
2026
2027   nat_send_all_to_node (vm, fragments_to_drop, node,
2028                         &node->errors[SNAT_IN2OUT_ERROR_DROP_FRAGMENT],
2029                         SNAT_IN2OUT_NEXT_DROP);
2030
2031   vec_free (fragments_to_drop);
2032   vec_free (fragments_to_loopback);
2033   return frame->n_vectors;
2034 }
2035
2036 /* *INDENT-OFF* */
2037 VLIB_REGISTER_NODE (nat44_in2out_reass_node) = {
2038   .name = "nat44-in2out-reass",
2039   .vector_size = sizeof (u32),
2040   .format_trace = format_nat44_reass_trace,
2041   .type = VLIB_NODE_TYPE_INTERNAL,
2042
2043   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
2044   .error_strings = snat_in2out_error_strings,
2045
2046   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
2047   .next_nodes = {
2048     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
2049     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
2050     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2051     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2052     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
2053   },
2054 };
2055 /* *INDENT-ON* */
2056
2057 VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
2058                                       vlib_node_runtime_t * node,
2059                                       vlib_frame_t * frame)
2060 {
2061   u32 n_left_from, *from, *to_next;
2062   snat_in2out_next_t next_index;
2063   u32 pkts_processed = 0;
2064   snat_main_t *sm = &snat_main;
2065   u32 stats_node_index;
2066
2067   stats_node_index = sm->in2out_fast_node_index;
2068
2069   from = vlib_frame_vector_args (frame);
2070   n_left_from = frame->n_vectors;
2071   next_index = node->cached_next_index;
2072
2073   while (n_left_from > 0)
2074     {
2075       u32 n_left_to_next;
2076
2077       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2078
2079       while (n_left_from > 0 && n_left_to_next > 0)
2080         {
2081           u32 bi0;
2082           vlib_buffer_t *b0;
2083           u32 next0;
2084           u32 sw_if_index0;
2085           ip4_header_t *ip0;
2086           ip_csum_t sum0;
2087           u32 new_addr0, old_addr0;
2088           u16 old_port0, new_port0;
2089           udp_header_t *udp0;
2090           tcp_header_t *tcp0;
2091           icmp46_header_t *icmp0;
2092           snat_session_key_t key0, sm0;
2093           u32 proto0;
2094           u32 rx_fib_index0;
2095
2096           /* speculatively enqueue b0 to the current next frame */
2097           bi0 = from[0];
2098           to_next[0] = bi0;
2099           from += 1;
2100           to_next += 1;
2101           n_left_from -= 1;
2102           n_left_to_next -= 1;
2103
2104           b0 = vlib_get_buffer (vm, bi0);
2105           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
2106
2107           ip0 = vlib_buffer_get_current (b0);
2108           udp0 = ip4_next_header (ip0);
2109           tcp0 = (tcp_header_t *) udp0;
2110           icmp0 = (icmp46_header_t *) udp0;
2111
2112           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2113           rx_fib_index0 =
2114             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
2115
2116           if (PREDICT_FALSE (ip0->ttl == 1))
2117             {
2118               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
2119               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
2120                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
2121                                            0);
2122               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
2123               goto trace0;
2124             }
2125
2126           proto0 = ip_proto_to_snat_proto (ip0->protocol);
2127
2128           if (PREDICT_FALSE (proto0 == ~0))
2129             goto trace0;
2130
2131           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
2132             {
2133               next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
2134                                    rx_fib_index0, node, next0, ~0, 0, 0);
2135               goto trace0;
2136             }
2137
2138           key0.addr = ip0->src_address;
2139           key0.protocol = proto0;
2140           key0.port = udp0->src_port;
2141           key0.fib_index = rx_fib_index0;
2142
2143           if (snat_static_mapping_match (sm, key0, &sm0, 0, 0, 0, 0, 0, 0))
2144             {
2145               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
2146               next0 = SNAT_IN2OUT_NEXT_DROP;
2147               goto trace0;
2148             }
2149
2150           new_addr0 = sm0.addr.as_u32;
2151           new_port0 = sm0.port;
2152           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
2153           old_addr0 = ip0->src_address.as_u32;
2154           ip0->src_address.as_u32 = new_addr0;
2155
2156           sum0 = ip0->checksum;
2157           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2158                                  ip4_header_t,
2159                                  src_address /* changed member */ );
2160           ip0->checksum = ip_csum_fold (sum0);
2161
2162           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
2163             {
2164               old_port0 = udp0->src_port;
2165               udp0->src_port = new_port0;
2166
2167               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
2168                 {
2169                   sum0 = tcp0->checksum;
2170                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2171                                          ip4_header_t,
2172                                          dst_address /* changed member */ );
2173                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
2174                                          ip4_header_t /* cheat */ ,
2175                                          length /* changed member */ );
2176                   mss_clamping (sm, tcp0, &sum0);
2177                   tcp0->checksum = ip_csum_fold (sum0);
2178                 }
2179               else if (udp0->checksum)
2180                 {
2181                   sum0 = udp0->checksum;
2182                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2183                                          ip4_header_t,
2184                                          dst_address /* changed member */ );
2185                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
2186                                          ip4_header_t /* cheat */ ,
2187                                          length /* changed member */ );
2188                   udp0->checksum = ip_csum_fold (sum0);
2189                 }
2190             }
2191           else
2192             {
2193               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
2194                 {
2195                   sum0 = tcp0->checksum;
2196                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2197                                          ip4_header_t,
2198                                          dst_address /* changed member */ );
2199                   mss_clamping (sm, tcp0, &sum0);
2200                   tcp0->checksum = ip_csum_fold (sum0);
2201                 }
2202               else if (udp0->checksum)
2203                 {
2204                   sum0 = udp0->checksum;
2205                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2206                                          ip4_header_t,
2207                                          dst_address /* changed member */ );
2208                   udp0->checksum = ip_csum_fold (sum0);
2209                 }
2210             }
2211
2212           /* Hairpinning */
2213           snat_hairpinning (sm, b0, ip0, udp0, tcp0, proto0, 0);
2214
2215         trace0:
2216           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
2217                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
2218             {
2219               snat_in2out_trace_t *t =
2220                 vlib_add_trace (vm, node, b0, sizeof (*t));
2221               t->sw_if_index = sw_if_index0;
2222               t->next_index = next0;
2223             }
2224
2225           pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
2226
2227           /* verify speculative enqueue, maybe switch current next frame */
2228           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
2229                                            to_next, n_left_to_next,
2230                                            bi0, next0);
2231         }
2232
2233       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2234     }
2235
2236   vlib_node_increment_counter (vm, stats_node_index,
2237                                SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
2238                                pkts_processed);
2239   return frame->n_vectors;
2240 }
2241
2242
2243 /* *INDENT-OFF* */
2244 VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
2245   .name = "nat44-in2out-fast",
2246   .vector_size = sizeof (u32),
2247   .format_trace = format_snat_in2out_fast_trace,
2248   .type = VLIB_NODE_TYPE_INTERNAL,
2249
2250   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
2251   .error_strings = snat_in2out_error_strings,
2252
2253   .runtime_data_bytes = sizeof (snat_runtime_t),
2254
2255   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
2256
2257   /* edit / add dispositions here */
2258   .next_nodes = {
2259     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
2260     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
2261     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2262     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2263     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
2264   },
2265 };
2266 /* *INDENT-ON* */
2267
2268 /*
2269  * fd.io coding-style-patch-verification: ON
2270  *
2271  * Local Variables:
2272  * eval: (c-set-style "gnu")
2273  * End:
2274  */