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 <nat/nat.h>
  28 #include <nat/nat_ipfix_logging.h>
  29 #include <nat/nat_reass.h>
  30 #include <nat/nat_inlines.h>
  31 #include <nat/nat_syslog.h>
  32
  33 #include <vppinfra/hash.h>
  34 #include <vppinfra/error.h>
  35 #include <vppinfra/elog.h>
  36
  37 typedef struct
  38 {
  39   u32 sw_if_index;
  40   u32 next_index;
  41   u32 session_index;
  42   u32 is_slow_path;
  43 } snat_in2out_trace_t;
  44
  45 /* packet trace format function */
  46 static u8 *
  47 format_snat_in2out_trace (u8 * s, va_list * args)
  48 {
  49   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  50   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  51   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  52   char *tag;
  53
  54   tag = t->is_slow_path ? "NAT44_IN2OUT_SLOW_PATH" : "NAT44_IN2OUT_FAST_PATH";
  55
  56   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  57               t->sw_if_index, t->next_index, t->session_index);
  58
  59   return s;
  60 }
  61
  62 static u8 *
  63 format_snat_in2out_fast_trace (u8 * s, va_list * args)
  64 {
  65   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  66   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  67   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  68
  69   s = format (s, "NAT44_IN2OUT_FAST: sw_if_index %d, next index %d",
  70               t->sw_if_index, t->next_index);
  71
  72   return s;
  73 }
  74
  75 vlib_node_registration_t snat_in2out_node;
  76 vlib_node_registration_t snat_in2out_slowpath_node;
  77 vlib_node_registration_t snat_in2out_fast_node;
  78 vlib_node_registration_t snat_in2out_output_node;
  79 vlib_node_registration_t snat_in2out_output_slowpath_node;
  80 vlib_node_registration_t nat44_in2out_reass_node;
  81
  82 #define foreach_snat_in2out_error                       \
  83 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
  84 _(IN2OUT_PACKETS, "good in2out packets processed")      \
  85 _(OUT_OF_PORTS, "out of ports")                         \
  86 _(BAD_OUTSIDE_FIB, "outside VRF ID not found")          \
  87 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  88 _(NO_TRANSLATION, "no translation")                     \
  89 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
  90 _(DROP_FRAGMENT, "drop fragment")                       \
  91 _(MAX_REASS, "maximum reassemblies exceeded")           \
  92 _(MAX_FRAG, "maximum fragments per reassembly exceeded")\
  93 _(TCP_PACKETS, "TCP packets")                           \
  94 _(UDP_PACKETS, "UDP packets")                           \
  95 _(ICMP_PACKETS, "ICMP packets")                         \
  96 _(OTHER_PACKETS, "other protocol packets")              \
  97 _(FRAGMENTS, "fragments")                               \
  98 _(CACHED_FRAGMENTS, "cached fragments")                 \
  99 _(PROCESSED_FRAGMENTS, "processed fragments")
 100
 101 typedef enum
 102 {
 103 #define _(sym,str) SNAT_IN2OUT_ERROR_##sym,
 104   foreach_snat_in2out_error
 105 #undef _
 106     SNAT_IN2OUT_N_ERROR,
 107 } snat_in2out_error_t;
 108
 109 static char *snat_in2out_error_strings[] = {
 110 #define _(sym,string) string,
 111   foreach_snat_in2out_error
 112 #undef _
 113 };
 114
 115 typedef enum
 116 {
 117   SNAT_IN2OUT_NEXT_LOOKUP,
 118   SNAT_IN2OUT_NEXT_DROP,
 119   SNAT_IN2OUT_NEXT_ICMP_ERROR,
 120   SNAT_IN2OUT_NEXT_SLOW_PATH,
 121   SNAT_IN2OUT_NEXT_REASS,
 122   SNAT_IN2OUT_N_NEXT,
 123 } snat_in2out_next_t;
 124
 125 static inline int
 126 snat_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 127                     u32 sw_if_index0, ip4_header_t * ip0, u32 proto0,
 128                     u32 rx_fib_index0, u32 thread_index)
 129 {
 130   udp_header_t *udp0 = ip4_next_header (ip0);
 131   snat_session_key_t key0, sm0;
 132   clib_bihash_kv_8_8_t kv0, value0;
 133
 134   key0.addr = ip0->dst_address;
 135   key0.port = udp0->dst_port;
 136   key0.protocol = proto0;
 137   key0.fib_index = sm->outside_fib_index;
 138   kv0.key = key0.as_u64;
 139
 140   /* NAT packet aimed at external address if */
 141   /* has active sessions */
 142   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
 143                               &value0))
 144     {
 145       /* or is static mappings */
 146       if (!snat_static_mapping_match (sm, key0, &sm0, 1, 0, 0, 0, 0, 0))
 147         return 0;
 148     }
 149   else
 150     return 0;
 151
 152   if (sm->forwarding_enabled)
 153     return 1;
 154
 155   return snat_not_translate_fast (sm, node, sw_if_index0, ip0, proto0,
 156                                   rx_fib_index0);
 157 }
 158
 159 static inline int
 160 nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
 161                                   u32 proto0, u16 src_port, u16 dst_port,
 162                                   u32 thread_index, u32 sw_if_index)
 163 {
 164   snat_session_key_t key0;
 165   clib_bihash_kv_8_8_t kv0, value0;
 166   snat_interface_t *i;
 167
 168   /* src NAT check */
 169   key0.addr = ip0->src_address;
 170   key0.port = src_port;
 171   key0.protocol = proto0;
 172   key0.fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 173   kv0.key = key0.as_u64;
 174
 175   if (!clib_bihash_search_8_8
 176       (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
 177     return 1;
 178
 179   /* dst NAT check */
 180   key0.addr = ip0->dst_address;
 181   key0.port = dst_port;
 182   key0.protocol = proto0;
 183   kv0.key = key0.as_u64;
 184   if (!clib_bihash_search_8_8
 185       (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
 186     {
 187       /* hairpinning */
 188     /* *INDENT-OFF* */
 189     pool_foreach (i, sm->output_feature_interfaces,
 190     ({
 191       if ((nat_interface_is_inside(i)) && (sw_if_index == i->sw_if_index))
 192         return 0;
 193     }));
 194     /* *INDENT-ON* */
 195       return 1;
 196     }
 197
 198   return 0;
 199 }
 200
 201 int
 202 nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
 203 {
 204   snat_main_t *sm = &snat_main;
 205   nat44_is_idle_session_ctx_t *ctx = arg;
 206   snat_session_t *s;
 207   u64 sess_timeout_time;
 208   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 209                                                        ctx->thread_index);
 210   clib_bihash_kv_8_8_t s_kv;
 211
 212   s = pool_elt_at_index (tsm->sessions, kv->value);
 213   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 214   if (ctx->now >= sess_timeout_time)
 215     {
 216       s_kv.key = s->out2in.as_u64;
 217       if (clib_bihash_add_del_8_8 (&tsm->out2in, &s_kv, 0))
 218         nat_log_warn ("out2in key del failed");
 219
 220       snat_ipfix_logging_nat44_ses_delete (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       if (!snat_is_session_static (s))
 233         snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 234                                             &s->out2in);
 235
 236       nat44_delete_session (sm, s, ctx->thread_index);
 237       return 1;
 238     }
 239
 240   return 0;
 241 }
 242
 243 static u32
 244 slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 245            ip4_header_t * ip0,
 246            u32 rx_fib_index0,
 247            snat_session_key_t * key0,
 248            snat_session_t ** sessionp,
 249            vlib_node_runtime_t * node, u32 next0, u32 thread_index, f64 now)
 250 {
 251   snat_user_t *u;
 252   snat_session_t *s = 0;
 253   clib_bihash_kv_8_8_t kv0;
 254   snat_session_key_t key1;
 255   udp_header_t *udp0 = ip4_next_header (ip0);
 256   u8 is_sm = 0;
 257   nat_outside_fib_t *outside_fib;
 258   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 259   u8 identity_nat;
 260   fib_prefix_t pfx = {
 261     .fp_proto = FIB_PROTOCOL_IP4,
 262     .fp_len = 32,
 263     .fp_addr = {
 264                 .ip4.as_u32 = ip0->dst_address.as_u32,
 265                 },
 266   };
 267   nat44_is_idle_session_ctx_t ctx0;
 268
 269   if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 270     {
 271       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_SESSIONS_EXCEEDED];
 272       nat_ipfix_logging_max_sessions (sm->max_translations);
 273       nat_log_notice ("maximum sessions exceeded");
 274       return SNAT_IN2OUT_NEXT_DROP;
 275     }
 276
 277   key1.protocol = key0->protocol;
 278
 279   /* First try to match static mapping by local address and port */
 280   if (snat_static_mapping_match
 281       (sm, *key0, &key1, 0, 0, 0, 0, 0, &identity_nat))
 282     {
 283       /* Try to create dynamic translation */
 284       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index0,
 285                                                thread_index, &key1,
 286                                                sm->port_per_thread,
 287                                                sm->per_thread_data
 288                                                [thread_index].snat_thread_index))
 289         {
 290           b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
 291           return SNAT_IN2OUT_NEXT_DROP;
 292         }
 293     }
 294   else
 295     {
 296       if (PREDICT_FALSE (identity_nat))
 297         {
 298           *sessionp = s;
 299           return next0;
 300         }
 301
 302       is_sm = 1;
 303     }
 304
 305   u = nat_user_get_or_create (sm, &ip0->src_address, rx_fib_index0,
 306                               thread_index);
 307   if (!u)
 308     {
 309       nat_log_warn ("create NAT user failed");
 310       return SNAT_IN2OUT_NEXT_DROP;
 311     }
 312
 313   s = nat_session_alloc_or_recycle (sm, u, thread_index);
 314   if (!s)
 315     {
 316       nat44_delete_user_with_no_session (sm, u, thread_index);
 317       nat_log_warn ("create NAT session failed");
 318       return SNAT_IN2OUT_NEXT_DROP;
 319     }
 320
 321   if (is_sm)
 322     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 323   user_session_increment (sm, u, is_sm);
 324   s->in2out = *key0;
 325   s->out2in = key1;
 326   s->out2in.protocol = key0->protocol;
 327   s->out2in.fib_index = sm->outside_fib_index;
 328   switch (vec_len (sm->outside_fibs))
 329     {
 330     case 0:
 331       s->out2in.fib_index = sm->outside_fib_index;
 332       break;
 333     case 1:
 334       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 335       break;
 336     default:
 337       /* *INDENT-OFF* */
 338       vec_foreach (outside_fib, sm->outside_fibs)
 339         {
 340           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 341           if (FIB_NODE_INDEX_INVALID != fei)
 342             {
 343               if (fib_entry_get_resolving_interface (fei) != ~0)
 344                 {
 345                   s->out2in.fib_index = outside_fib->fib_index;
 346                   break;
 347                 }
 348             }
 349         }
 350       /* *INDENT-ON* */
 351       break;
 352     }
 353   s->ext_host_addr.as_u32 = ip0->dst_address.as_u32;
 354   s->ext_host_port = udp0->dst_port;
 355   *sessionp = s;
 356
 357   /* Add to translation hashes */
 358   ctx0.now = now;
 359   ctx0.thread_index = thread_index;
 360   kv0.key = s->in2out.as_u64;
 361   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 362   if (clib_bihash_add_or_overwrite_stale_8_8
 363       (&sm->per_thread_data[thread_index].in2out, &kv0,
 364        nat44_i2o_is_idle_session_cb, &ctx0))
 365     nat_log_notice ("in2out key add failed");
 366
 367   kv0.key = s->out2in.as_u64;
 368   kv0.value = s - sm->per_thread_data[thread_index].sessions;
 369
 370   if (clib_bihash_add_or_overwrite_stale_8_8
 371       (&sm->per_thread_data[thread_index].out2in, &kv0,
 372        nat44_o2i_is_idle_session_cb, &ctx0))
 373     nat_log_notice ("out2in key add failed");
 374
 375   /* log NAT event */
 376   snat_ipfix_logging_nat44_ses_create (s->in2out.addr.as_u32,
 377                                        s->out2in.addr.as_u32,
 378                                        s->in2out.protocol,
 379                                        s->in2out.port,
 380                                        s->out2in.port, s->in2out.fib_index);
 381
 382   nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
 383                            &s->in2out.addr, s->in2out.port, &s->out2in.addr,
 384                            s->out2in.port, s->in2out.protocol);
 385
 386   return next0;
 387 }
 388
 389 static_always_inline
 390   snat_in2out_error_t icmp_get_key (ip4_header_t * ip0,
 391                                     snat_session_key_t * p_key0)
 392 {
 393   icmp46_header_t *icmp0;
 394   snat_session_key_t key0;
 395   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 396   ip4_header_t *inner_ip0 = 0;
 397   void *l4_header = 0;
 398   icmp46_header_t *inner_icmp0;
 399
 400   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 401   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 402
 403   if (!icmp_is_error_message (icmp0))
 404     {
 405       key0.protocol = SNAT_PROTOCOL_ICMP;
 406       key0.addr = ip0->src_address;
 407       key0.port = echo0->identifier;
 408     }
 409   else
 410     {
 411       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 412       l4_header = ip4_next_header (inner_ip0);
 413       key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
 414       key0.addr = inner_ip0->dst_address;
 415       switch (key0.protocol)
 416         {
 417         case SNAT_PROTOCOL_ICMP:
 418           inner_icmp0 = (icmp46_header_t *) l4_header;
 419           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 420           key0.port = inner_echo0->identifier;
 421           break;
 422         case SNAT_PROTOCOL_UDP:
 423         case SNAT_PROTOCOL_TCP:
 424           key0.port = ((tcp_udp_header_t *) l4_header)->dst_port;
 425           break;
 426         default:
 427           return SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL;
 428         }
 429     }
 430   *p_key0 = key0;
 431   return -1;                    /* success */
 432 }
 433
 434 /**
 435  * Get address and port values to be used for ICMP packet translation
 436  * and create session if needed
 437  *
 438  * @param[in,out] sm             NAT main
 439  * @param[in,out] node           NAT node runtime
 440  * @param[in] thread_index       thread index
 441  * @param[in,out] b0             buffer containing packet to be translated
 442  * @param[out] p_proto           protocol used for matching
 443  * @param[out] p_value           address and port after NAT translation
 444  * @param[out] p_dont_translate  if packet should not be translated
 445  * @param d                      optional parameter
 446  * @param e                      optional parameter
 447  */
 448 u32
 449 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
 450                         u32 thread_index, vlib_buffer_t * b0,
 451                         ip4_header_t * ip0, u8 * p_proto,
 452                         snat_session_key_t * p_value,
 453                         u8 * p_dont_translate, void *d, void *e)
 454 {
 455   icmp46_header_t *icmp0;
 456   u32 sw_if_index0;
 457   u32 rx_fib_index0;
 458   snat_session_key_t key0;
 459   snat_session_t *s0 = 0;
 460   u8 dont_translate = 0;
 461   clib_bihash_kv_8_8_t kv0, value0;
 462   u32 next0 = ~0;
 463   int err;
 464
 465   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 466   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 467   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 468
 469   err = icmp_get_key (ip0, &key0);
 470   if (err != -1)
 471     {
 472       b0->error = node->errors[err];
 473       next0 = SNAT_IN2OUT_NEXT_DROP;
 474       goto out;
 475     }
 476   key0.fib_index = rx_fib_index0;
 477
 478   kv0.key = key0.as_u64;
 479
 480   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].in2out, &kv0,
 481                               &value0))
 482     {
 483       if (vnet_buffer (b0)->sw_if_index[VLIB_TX] != ~0)
 484         {
 485           if (PREDICT_FALSE (nat_not_translate_output_feature (sm, ip0,
 486                                                                key0.protocol,
 487                                                                key0.port,
 488                                                                key0.port,
 489                                                                thread_index,
 490                                                                sw_if_index0)))
 491             {
 492               dont_translate = 1;
 493               goto out;
 494             }
 495         }
 496       else
 497         {
 498           if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
 499                                                  ip0, SNAT_PROTOCOL_ICMP,
 500                                                  rx_fib_index0,
 501                                                  thread_index)))
 502             {
 503               dont_translate = 1;
 504               goto out;
 505             }
 506         }
 507
 508       if (PREDICT_FALSE (icmp_is_error_message (icmp0)))
 509         {
 510           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 511           next0 = SNAT_IN2OUT_NEXT_DROP;
 512           goto out;
 513         }
 514
 515       next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0,
 516                          thread_index, vlib_time_now (sm->vlib_main));
 517
 518       if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
 519         goto out;
 520
 521       if (!s0)
 522         {
 523           dont_translate = 1;
 524           goto out;
 525         }
 526     }
 527   else
 528     {
 529       if (PREDICT_FALSE (icmp0->type != ICMP4_echo_request &&
 530                          icmp0->type != ICMP4_echo_reply &&
 531                          !icmp_is_error_message (icmp0)))
 532         {
 533           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 534           next0 = SNAT_IN2OUT_NEXT_DROP;
 535           goto out;
 536         }
 537
 538       s0 = pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
 539                               value0.value);
 540     }
 541
 542 out:
 543   *p_proto = key0.protocol;
 544   if (s0)
 545     *p_value = s0->out2in;
 546   *p_dont_translate = dont_translate;
 547   if (d)
 548     *(snat_session_t **) d = s0;
 549   return next0;
 550 }
 551
 552 /**
 553  * Get address and port values to be used for ICMP packet translation
 554  *
 555  * @param[in] sm                 NAT main
 556  * @param[in,out] node           NAT node runtime
 557  * @param[in] thread_index       thread index
 558  * @param[in,out] b0             buffer containing packet to be translated
 559  * @param[out] p_proto           protocol used for matching
 560  * @param[out] p_value           address and port after NAT translation
 561  * @param[out] p_dont_translate  if packet should not be translated
 562  * @param d                      optional parameter
 563  * @param e                      optional parameter
 564  */
 565 u32
 566 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
 567                         u32 thread_index, vlib_buffer_t * b0,
 568                         ip4_header_t * ip0, u8 * p_proto,
 569                         snat_session_key_t * p_value,
 570                         u8 * p_dont_translate, void *d, void *e)
 571 {
 572   icmp46_header_t *icmp0;
 573   u32 sw_if_index0;
 574   u32 rx_fib_index0;
 575   snat_session_key_t key0;
 576   snat_session_key_t sm0;
 577   u8 dont_translate = 0;
 578   u8 is_addr_only;
 579   u32 next0 = ~0;
 580   int err;
 581
 582   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 583   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 584   rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 585
 586   err = icmp_get_key (ip0, &key0);
 587   if (err != -1)
 588     {
 589       b0->error = node->errors[err];
 590       next0 = SNAT_IN2OUT_NEXT_DROP;
 591       goto out2;
 592     }
 593   key0.fib_index = rx_fib_index0;
 594
 595   if (snat_static_mapping_match
 596       (sm, key0, &sm0, 0, &is_addr_only, 0, 0, 0, 0))
 597     {
 598       if (PREDICT_FALSE (snat_not_translate_fast (sm, node, sw_if_index0, ip0,
 599                                                   IP_PROTOCOL_ICMP,
 600                                                   rx_fib_index0)))
 601         {
 602           dont_translate = 1;
 603           goto out;
 604         }
 605
 606       if (icmp_is_error_message (icmp0))
 607         {
 608           next0 = SNAT_IN2OUT_NEXT_DROP;
 609           goto out;
 610         }
 611
 612       b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
 613       next0 = SNAT_IN2OUT_NEXT_DROP;
 614       goto out;
 615     }
 616
 617   if (PREDICT_FALSE (icmp0->type != ICMP4_echo_request &&
 618                      (icmp0->type != ICMP4_echo_reply || !is_addr_only) &&
 619                      !icmp_is_error_message (icmp0)))
 620     {
 621       b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 622       next0 = SNAT_IN2OUT_NEXT_DROP;
 623       goto out;
 624     }
 625
 626 out:
 627   *p_value = sm0;
 628 out2:
 629   *p_proto = key0.protocol;
 630   *p_dont_translate = dont_translate;
 631   return next0;
 632 }
 633
 634 u32
 635 icmp_in2out (snat_main_t * sm,
 636              vlib_buffer_t * b0,
 637              ip4_header_t * ip0,
 638              icmp46_header_t * icmp0,
 639              u32 sw_if_index0,
 640              u32 rx_fib_index0,
 641              vlib_node_runtime_t * node,
 642              u32 next0, u32 thread_index, void *d, void *e)
 643 {
 644   snat_session_key_t sm0;
 645   u8 protocol;
 646   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 647   ip4_header_t *inner_ip0;
 648   void *l4_header = 0;
 649   icmp46_header_t *inner_icmp0;
 650   u8 dont_translate;
 651   u32 new_addr0, old_addr0;
 652   u16 old_id0, new_id0;
 653   u16 old_checksum0, new_checksum0;
 654   ip_csum_t sum0;
 655   u16 checksum0;
 656   u32 next0_tmp;
 657
 658   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 659
 660   next0_tmp = sm->icmp_match_in2out_cb (sm, node, thread_index, b0, ip0,
 661                                         &protocol, &sm0, &dont_translate, d,
 662                                         e);
 663   if (next0_tmp != ~0)
 664     next0 = next0_tmp;
 665   if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
 666     goto out;
 667
 668   if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
 669     {
 670       sum0 = ip_incremental_checksum_buffer (sm->vlib_main, b0, (u8 *) icmp0 -
 671                                              (u8 *)
 672                                              vlib_buffer_get_current (b0),
 673                                              ntohs (ip0->length) -
 674                                              ip4_header_bytes (ip0), 0);
 675       checksum0 = ~ip_csum_fold (sum0);
 676       if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff))
 677         {
 678           next0 = SNAT_IN2OUT_NEXT_DROP;
 679           goto out;
 680         }
 681     }
 682
 683   old_addr0 = ip0->src_address.as_u32;
 684   new_addr0 = ip0->src_address.as_u32 = sm0.addr.as_u32;
 685
 686   sum0 = ip0->checksum;
 687   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 688                          src_address /* changed member */ );
 689   ip0->checksum = ip_csum_fold (sum0);
 690
 691   if (icmp0->checksum == 0)
 692     icmp0->checksum = 0xffff;
 693
 694   if (!icmp_is_error_message (icmp0))
 695     {
 696       new_id0 = sm0.port;
 697       if (PREDICT_FALSE (new_id0 != echo0->identifier))
 698         {
 699           old_id0 = echo0->identifier;
 700           new_id0 = sm0.port;
 701           echo0->identifier = new_id0;
 702
 703           sum0 = icmp0->checksum;
 704           sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 705                                  identifier);
 706           icmp0->checksum = ip_csum_fold (sum0);
 707         }
 708     }
 709   else
 710     {
 711       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 712       l4_header = ip4_next_header (inner_ip0);
 713
 714       if (!ip4_header_checksum_is_valid (inner_ip0))
 715         {
 716           next0 = SNAT_IN2OUT_NEXT_DROP;
 717           goto out;
 718         }
 719
 720       /* update inner destination IP address */
 721       old_addr0 = inner_ip0->dst_address.as_u32;
 722       inner_ip0->dst_address = sm0.addr;
 723       new_addr0 = inner_ip0->dst_address.as_u32;
 724       sum0 = icmp0->checksum;
 725       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 726                              dst_address /* changed member */ );
 727       icmp0->checksum = ip_csum_fold (sum0);
 728
 729       /* update inner IP header checksum */
 730       old_checksum0 = inner_ip0->checksum;
 731       sum0 = inner_ip0->checksum;
 732       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 733                              dst_address /* changed member */ );
 734       inner_ip0->checksum = ip_csum_fold (sum0);
 735       new_checksum0 = inner_ip0->checksum;
 736       sum0 = icmp0->checksum;
 737       sum0 = ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
 738                              checksum);
 739       icmp0->checksum = ip_csum_fold (sum0);
 740
 741       switch (protocol)
 742         {
 743         case SNAT_PROTOCOL_ICMP:
 744           inner_icmp0 = (icmp46_header_t *) l4_header;
 745           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 746
 747           old_id0 = inner_echo0->identifier;
 748           new_id0 = sm0.port;
 749           inner_echo0->identifier = new_id0;
 750
 751           sum0 = icmp0->checksum;
 752           sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 753                                  identifier);
 754           icmp0->checksum = ip_csum_fold (sum0);
 755           break;
 756         case SNAT_PROTOCOL_UDP:
 757         case SNAT_PROTOCOL_TCP:
 758           old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
 759           new_id0 = sm0.port;
 760           ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
 761
 762           sum0 = icmp0->checksum;
 763           sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
 764                                  dst_port);
 765           icmp0->checksum = ip_csum_fold (sum0);
 766           break;
 767         default:
 768           ASSERT (0);
 769         }
 770     }
 771
 772   if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
 773     {
 774       if (sm->deterministic ||
 775           0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
 776                                       sm->endpoint_dependent))
 777         vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
 778     }
 779
 780 out:
 781   return next0;
 782 }
 783
 784 static inline u32
 785 icmp_in2out_slow_path (snat_main_t * sm,
 786                        vlib_buffer_t * b0,
 787                        ip4_header_t * ip0,
 788                        icmp46_header_t * icmp0,
 789                        u32 sw_if_index0,
 790                        u32 rx_fib_index0,
 791                        vlib_node_runtime_t * node,
 792                        u32 next0,
 793                        f64 now, u32 thread_index, snat_session_t ** p_s0)
 794 {
 795   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 796                        next0, thread_index, p_s0, 0);
 797   snat_session_t *s0 = *p_s0;
 798   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
 799     {
 800       /* Accounting */
 801       nat44_session_update_counters (s0, now,
 802                                      vlib_buffer_length_in_chain
 803                                      (sm->vlib_main, b0));
 804       /* Per-user LRU list maintenance */
 805       nat44_session_update_lru (sm, s0, thread_index);
 806     }
 807   return next0;
 808 }
 809
 810 static int
 811 nat_in2out_sm_unknown_proto (snat_main_t * sm,
 812                              vlib_buffer_t * b,
 813                              ip4_header_t * ip, u32 rx_fib_index)
 814 {
 815   clib_bihash_kv_8_8_t kv, value;
 816   snat_static_mapping_t *m;
 817   snat_session_key_t m_key;
 818   u32 old_addr, new_addr;
 819   ip_csum_t sum;
 820
 821   m_key.addr = ip->src_address;
 822   m_key.port = 0;
 823   m_key.protocol = 0;
 824   m_key.fib_index = rx_fib_index;
 825   kv.key = m_key.as_u64;
 826   if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 827     return 1;
 828
 829   m = pool_elt_at_index (sm->static_mappings, value.value);
 830
 831   old_addr = ip->src_address.as_u32;
 832   new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 833   sum = ip->checksum;
 834   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 835   ip->checksum = ip_csum_fold (sum);
 836
 837
 838   /* Hairpinning */
 839   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 840     {
 841       vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 842       nat_hairpinning_sm_unknown_proto (sm, b, ip);
 843     }
 844
 845   return 0;
 846 }
 847
 848 static inline uword
 849 snat_in2out_node_fn_inline (vlib_main_t * vm,
 850                             vlib_node_runtime_t * node,
 851                             vlib_frame_t * frame, int is_slow_path,
 852                             int is_output_feature)
 853 {
 854   u32 n_left_from, *from, *to_next;
 855   snat_in2out_next_t next_index;
 856   u32 pkts_processed = 0;
 857   snat_main_t *sm = &snat_main;
 858   f64 now = vlib_time_now (vm);
 859   u32 stats_node_index;
 860   u32 thread_index = vm->thread_index;
 861   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 862     0, fragments = 0;
 863
 864   stats_node_index = is_slow_path ? snat_in2out_slowpath_node.index :
 865     snat_in2out_node.index;
 866
 867   from = vlib_frame_vector_args (frame);
 868   n_left_from = frame->n_vectors;
 869   next_index = node->cached_next_index;
 870
 871   while (n_left_from > 0)
 872     {
 873       u32 n_left_to_next;
 874
 875       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 876
 877       while (n_left_from >= 4 && n_left_to_next >= 2)
 878         {
 879           u32 bi0, bi1;
 880           vlib_buffer_t *b0, *b1;
 881           u32 next0, next1;
 882           u32 sw_if_index0, sw_if_index1;
 883           ip4_header_t *ip0, *ip1;
 884           ip_csum_t sum0, sum1;
 885           u32 new_addr0, old_addr0, new_addr1, old_addr1;
 886           u16 old_port0, new_port0, old_port1, new_port1;
 887           udp_header_t *udp0, *udp1;
 888           tcp_header_t *tcp0, *tcp1;
 889           icmp46_header_t *icmp0, *icmp1;
 890           snat_session_key_t key0, key1;
 891           u32 rx_fib_index0, rx_fib_index1;
 892           u32 proto0, proto1;
 893           snat_session_t *s0 = 0, *s1 = 0;
 894           clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
 895           u32 iph_offset0 = 0, iph_offset1 = 0;
 896
 897           /* Prefetch next iteration. */
 898           {
 899             vlib_buffer_t *p2, *p3;
 900
 901             p2 = vlib_get_buffer (vm, from[2]);
 902             p3 = vlib_get_buffer (vm, from[3]);
 903
 904             vlib_prefetch_buffer_header (p2, LOAD);
 905             vlib_prefetch_buffer_header (p3, LOAD);
 906
 907             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 908             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 909           }
 910
 911           /* speculatively enqueue b0 and b1 to the current next frame */
 912           to_next[0] = bi0 = from[0];
 913           to_next[1] = bi1 = from[1];
 914           from += 2;
 915           to_next += 2;
 916           n_left_from -= 2;
 917           n_left_to_next -= 2;
 918
 919           b0 = vlib_get_buffer (vm, bi0);
 920           b1 = vlib_get_buffer (vm, bi1);
 921
 922           if (is_output_feature)
 923             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
 924
 925           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 926                                   iph_offset0);
 927
 928           udp0 = ip4_next_header (ip0);
 929           tcp0 = (tcp_header_t *) udp0;
 930           icmp0 = (icmp46_header_t *) udp0;
 931
 932           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 933           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 934                                    sw_if_index0);
 935
 936           next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
 937
 938           if (PREDICT_FALSE (ip0->ttl == 1))
 939             {
 940               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 941               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 942                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 943                                            0);
 944               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
 945               goto trace00;
 946             }
 947
 948           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 949
 950           /* Next configured feature, probably ip4-lookup */
 951           if (is_slow_path)
 952             {
 953               if (PREDICT_FALSE (proto0 == ~0))
 954                 {
 955                   if (nat_in2out_sm_unknown_proto
 956                       (sm, b0, ip0, rx_fib_index0))
 957                     {
 958                       next0 = SNAT_IN2OUT_NEXT_DROP;
 959                       b0->error =
 960                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
 961                     }
 962                   other_packets++;
 963                   goto trace00;
 964                 }
 965
 966               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 967                 {
 968                   next0 = icmp_in2out_slow_path
 969                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
 970                      node, next0, now, thread_index, &s0);
 971                   icmp_packets++;
 972                   goto trace00;
 973                 }
 974             }
 975           else
 976             {
 977               if (PREDICT_FALSE (proto0 == ~0))
 978                 {
 979                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 980                   goto trace00;
 981                 }
 982
 983               if (ip4_is_fragment (ip0))
 984                 {
 985                   next0 = SNAT_IN2OUT_NEXT_REASS;
 986                   fragments++;
 987                   goto trace00;
 988                 }
 989
 990               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 991                 {
 992                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 993                   goto trace00;
 994                 }
 995             }
 996
 997           key0.addr = ip0->src_address;
 998           key0.port = udp0->src_port;
 999           key0.protocol = proto0;
1000           key0.fib_index = rx_fib_index0;
1001
1002           kv0.key = key0.as_u64;
1003
1004           if (PREDICT_FALSE
1005               (clib_bihash_search_8_8
1006                (&sm->per_thread_data[thread_index].in2out, &kv0,
1007                 &value0) != 0))
1008             {
1009               if (is_slow_path)
1010                 {
1011                   if (is_output_feature)
1012                     {
1013                       if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1014                                                                            ip0,
1015                                                                            proto0,
1016                                                                            udp0->src_port,
1017                                                                            udp0->dst_port,
1018                                                                            thread_index,
1019                                                                            sw_if_index0)))
1020                         goto trace00;
1021                     }
1022                   else
1023                     {
1024                       if (PREDICT_FALSE
1025                           (snat_not_translate
1026                            (sm, node, sw_if_index0, ip0, proto0,
1027                             rx_fib_index0, thread_index)))
1028                         goto trace00;
1029                     }
1030
1031                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1032                                      &s0, node, next0, thread_index, now);
1033                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1034                     goto trace00;
1035
1036                   if (PREDICT_FALSE (!s0))
1037                     goto trace00;
1038                 }
1039               else
1040                 {
1041                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1042                   goto trace00;
1043                 }
1044             }
1045           else
1046             s0 =
1047               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1048                                  value0.value);
1049
1050           b0->flags |= VNET_BUFFER_F_IS_NATED;
1051
1052           old_addr0 = ip0->src_address.as_u32;
1053           ip0->src_address = s0->out2in.addr;
1054           new_addr0 = ip0->src_address.as_u32;
1055           if (!is_output_feature)
1056             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1057
1058           sum0 = ip0->checksum;
1059           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1060                                  ip4_header_t,
1061                                  src_address /* changed member */ );
1062           ip0->checksum = ip_csum_fold (sum0);
1063
1064           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1065             {
1066               old_port0 = tcp0->src_port;
1067               tcp0->src_port = s0->out2in.port;
1068               new_port0 = tcp0->src_port;
1069
1070               sum0 = tcp0->checksum;
1071               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1072                                      ip4_header_t,
1073                                      dst_address /* changed member */ );
1074               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1075                                      ip4_header_t /* cheat */ ,
1076                                      length /* changed member */ );
1077               mss_clamping (sm, tcp0, &sum0);
1078               tcp0->checksum = ip_csum_fold (sum0);
1079               tcp_packets++;
1080             }
1081           else
1082             {
1083               old_port0 = udp0->src_port;
1084               udp0->src_port = s0->out2in.port;
1085               udp0->checksum = 0;
1086               udp_packets++;
1087             }
1088
1089           /* Accounting */
1090           nat44_session_update_counters (s0, now,
1091                                          vlib_buffer_length_in_chain (vm,
1092                                                                       b0));
1093           /* Per-user LRU list maintenance */
1094           nat44_session_update_lru (sm, s0, thread_index);
1095         trace00:
1096
1097           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1098                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1099             {
1100               snat_in2out_trace_t *t =
1101                 vlib_add_trace (vm, node, b0, sizeof (*t));
1102               t->is_slow_path = is_slow_path;
1103               t->sw_if_index = sw_if_index0;
1104               t->next_index = next0;
1105               t->session_index = ~0;
1106               if (s0)
1107                 t->session_index =
1108                   s0 - sm->per_thread_data[thread_index].sessions;
1109             }
1110
1111           pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1112
1113           if (is_output_feature)
1114             iph_offset1 = vnet_buffer (b1)->ip.save_rewrite_length;
1115
1116           ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1117                                   iph_offset1);
1118
1119           udp1 = ip4_next_header (ip1);
1120           tcp1 = (tcp_header_t *) udp1;
1121           icmp1 = (icmp46_header_t *) udp1;
1122
1123           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1124           rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1125                                    sw_if_index1);
1126
1127           if (PREDICT_FALSE (ip1->ttl == 1))
1128             {
1129               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1130               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1131                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1132                                            0);
1133               next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1134               goto trace01;
1135             }
1136
1137           proto1 = ip_proto_to_snat_proto (ip1->protocol);
1138
1139           /* Next configured feature, probably ip4-lookup */
1140           if (is_slow_path)
1141             {
1142               if (PREDICT_FALSE (proto1 == ~0))
1143                 {
1144                   if (nat_in2out_sm_unknown_proto
1145                       (sm, b1, ip1, rx_fib_index1))
1146                     {
1147                       next1 = SNAT_IN2OUT_NEXT_DROP;
1148                       b1->error =
1149                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1150                     }
1151                   other_packets++;
1152                   goto trace01;
1153                 }
1154
1155               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1156                 {
1157                   next1 = icmp_in2out_slow_path
1158                     (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1159                      next1, now, thread_index, &s1);
1160                   icmp_packets++;
1161                   goto trace01;
1162                 }
1163             }
1164           else
1165             {
1166               if (PREDICT_FALSE (proto1 == ~0))
1167                 {
1168                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1169                   goto trace01;
1170                 }
1171
1172               if (ip4_is_fragment (ip1))
1173                 {
1174                   next1 = SNAT_IN2OUT_NEXT_REASS;
1175                   fragments++;
1176                   goto trace01;
1177                 }
1178
1179               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1180                 {
1181                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1182                   goto trace01;
1183                 }
1184             }
1185
1186           key1.addr = ip1->src_address;
1187           key1.port = udp1->src_port;
1188           key1.protocol = proto1;
1189           key1.fib_index = rx_fib_index1;
1190
1191           kv1.key = key1.as_u64;
1192
1193           if (PREDICT_FALSE
1194               (clib_bihash_search_8_8
1195                (&sm->per_thread_data[thread_index].in2out, &kv1,
1196                 &value1) != 0))
1197             {
1198               if (is_slow_path)
1199                 {
1200                   if (is_output_feature)
1201                     {
1202                       if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1203                                                                            ip1,
1204                                                                            proto1,
1205                                                                            udp1->src_port,
1206                                                                            udp1->dst_port,
1207                                                                            thread_index,
1208                                                                            sw_if_index1)))
1209                         goto trace01;
1210                     }
1211                   else
1212                     {
1213                       if (PREDICT_FALSE
1214                           (snat_not_translate
1215                            (sm, node, sw_if_index1, ip1, proto1,
1216                             rx_fib_index1, thread_index)))
1217                         goto trace01;
1218                     }
1219
1220                   next1 = slow_path (sm, b1, ip1, rx_fib_index1, &key1,
1221                                      &s1, node, next1, thread_index, now);
1222                   if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1223                     goto trace01;
1224
1225                   if (PREDICT_FALSE (!s1))
1226                     goto trace01;
1227                 }
1228               else
1229                 {
1230                   next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1231                   goto trace01;
1232                 }
1233             }
1234           else
1235             s1 =
1236               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1237                                  value1.value);
1238
1239           b1->flags |= VNET_BUFFER_F_IS_NATED;
1240
1241           old_addr1 = ip1->src_address.as_u32;
1242           ip1->src_address = s1->out2in.addr;
1243           new_addr1 = ip1->src_address.as_u32;
1244           if (!is_output_feature)
1245             vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1246
1247           sum1 = ip1->checksum;
1248           sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1249                                  ip4_header_t,
1250                                  src_address /* changed member */ );
1251           ip1->checksum = ip_csum_fold (sum1);
1252
1253           if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1254             {
1255               old_port1 = tcp1->src_port;
1256               tcp1->src_port = s1->out2in.port;
1257               new_port1 = tcp1->src_port;
1258
1259               sum1 = tcp1->checksum;
1260               sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1261                                      ip4_header_t,
1262                                      dst_address /* changed member */ );
1263               sum1 = ip_csum_update (sum1, old_port1, new_port1,
1264                                      ip4_header_t /* cheat */ ,
1265                                      length /* changed member */ );
1266               mss_clamping (sm, tcp1, &sum1);
1267               tcp1->checksum = ip_csum_fold (sum1);
1268               tcp_packets++;
1269             }
1270           else
1271             {
1272               old_port1 = udp1->src_port;
1273               udp1->src_port = s1->out2in.port;
1274               udp1->checksum = 0;
1275               udp_packets++;
1276             }
1277
1278           /* Accounting */
1279           nat44_session_update_counters (s1, now,
1280                                          vlib_buffer_length_in_chain (vm,
1281                                                                       b1));
1282           /* Per-user LRU list maintenance */
1283           nat44_session_update_lru (sm, s1, thread_index);
1284         trace01:
1285
1286           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1287                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1288             {
1289               snat_in2out_trace_t *t =
1290                 vlib_add_trace (vm, node, b1, sizeof (*t));
1291               t->sw_if_index = sw_if_index1;
1292               t->next_index = next1;
1293               t->session_index = ~0;
1294               if (s1)
1295                 t->session_index =
1296                   s1 - sm->per_thread_data[thread_index].sessions;
1297             }
1298
1299           pkts_processed += next1 == SNAT_IN2OUT_NEXT_LOOKUP;
1300
1301           /* verify speculative enqueues, maybe switch current next frame */
1302           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1303                                            to_next, n_left_to_next,
1304                                            bi0, bi1, next0, next1);
1305         }
1306
1307       while (n_left_from > 0 && n_left_to_next > 0)
1308         {
1309           u32 bi0;
1310           vlib_buffer_t *b0;
1311           u32 next0;
1312           u32 sw_if_index0;
1313           ip4_header_t *ip0;
1314           ip_csum_t sum0;
1315           u32 new_addr0, old_addr0;
1316           u16 old_port0, new_port0;
1317           udp_header_t *udp0;
1318           tcp_header_t *tcp0;
1319           icmp46_header_t *icmp0;
1320           snat_session_key_t key0;
1321           u32 rx_fib_index0;
1322           u32 proto0;
1323           snat_session_t *s0 = 0;
1324           clib_bihash_kv_8_8_t kv0, value0;
1325           u32 iph_offset0 = 0;
1326
1327           /* speculatively enqueue b0 to the current next frame */
1328           bi0 = from[0];
1329           to_next[0] = bi0;
1330           from += 1;
1331           to_next += 1;
1332           n_left_from -= 1;
1333           n_left_to_next -= 1;
1334
1335           b0 = vlib_get_buffer (vm, bi0);
1336           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1337
1338           if (is_output_feature)
1339             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
1340
1341           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1342                                   iph_offset0);
1343
1344           udp0 = ip4_next_header (ip0);
1345           tcp0 = (tcp_header_t *) udp0;
1346           icmp0 = (icmp46_header_t *) udp0;
1347
1348           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1349           rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1350                                    sw_if_index0);
1351
1352           if (PREDICT_FALSE (ip0->ttl == 1))
1353             {
1354               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1355               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1356                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1357                                            0);
1358               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1359               goto trace0;
1360             }
1361
1362           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1363
1364           /* Next configured feature, probably ip4-lookup */
1365           if (is_slow_path)
1366             {
1367               if (PREDICT_FALSE (proto0 == ~0))
1368                 {
1369                   if (nat_in2out_sm_unknown_proto
1370                       (sm, b0, ip0, rx_fib_index0))
1371                     {
1372                       next0 = SNAT_IN2OUT_NEXT_DROP;
1373                       b0->error =
1374                         node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1375                     }
1376                   other_packets++;
1377                   goto trace0;
1378                 }
1379
1380               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1381                 {
1382                   next0 = icmp_in2out_slow_path
1383                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1384                      next0, now, thread_index, &s0);
1385                   icmp_packets++;
1386                   goto trace0;
1387                 }
1388             }
1389           else
1390             {
1391               if (PREDICT_FALSE (proto0 == ~0))
1392                 {
1393                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1394                   goto trace0;
1395                 }
1396
1397               if (ip4_is_fragment (ip0))
1398                 {
1399                   next0 = SNAT_IN2OUT_NEXT_REASS;
1400                   fragments++;
1401                   goto trace0;
1402                 }
1403
1404               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1405                 {
1406                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1407                   goto trace0;
1408                 }
1409             }
1410
1411           key0.addr = ip0->src_address;
1412           key0.port = udp0->src_port;
1413           key0.protocol = proto0;
1414           key0.fib_index = rx_fib_index0;
1415
1416           kv0.key = key0.as_u64;
1417
1418           if (clib_bihash_search_8_8
1419               (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1420             {
1421               if (is_slow_path)
1422                 {
1423                   if (is_output_feature)
1424                     {
1425                       if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1426                                                                            ip0,
1427                                                                            proto0,
1428                                                                            udp0->src_port,
1429                                                                            udp0->dst_port,
1430                                                                            thread_index,
1431                                                                            sw_if_index0)))
1432                         goto trace0;
1433                     }
1434                   else
1435                     {
1436                       if (PREDICT_FALSE
1437                           (snat_not_translate
1438                            (sm, node, sw_if_index0, ip0, proto0,
1439                             rx_fib_index0, thread_index)))
1440                         goto trace0;
1441                     }
1442
1443                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1444                                      &s0, node, next0, thread_index, now);
1445
1446                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1447                     goto trace0;
1448
1449                   if (PREDICT_FALSE (!s0))
1450                     goto trace0;
1451                 }
1452               else
1453                 {
1454                   next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1455                   goto trace0;
1456                 }
1457             }
1458           else
1459             s0 =
1460               pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1461                                  value0.value);
1462
1463           b0->flags |= VNET_BUFFER_F_IS_NATED;
1464
1465           old_addr0 = ip0->src_address.as_u32;
1466           ip0->src_address = s0->out2in.addr;
1467           new_addr0 = ip0->src_address.as_u32;
1468           if (!is_output_feature)
1469             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1470
1471           sum0 = ip0->checksum;
1472           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1473                                  ip4_header_t,
1474                                  src_address /* changed member */ );
1475           ip0->checksum = ip_csum_fold (sum0);
1476
1477           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1478             {
1479               old_port0 = tcp0->src_port;
1480               tcp0->src_port = s0->out2in.port;
1481               new_port0 = tcp0->src_port;
1482
1483               sum0 = tcp0->checksum;
1484               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1485                                      ip4_header_t,
1486                                      dst_address /* changed member */ );
1487               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1488                                      ip4_header_t /* cheat */ ,
1489                                      length /* changed member */ );
1490               mss_clamping (sm, tcp0, &sum0);
1491               tcp0->checksum = ip_csum_fold (sum0);
1492               tcp_packets++;
1493             }
1494           else
1495             {
1496               old_port0 = udp0->src_port;
1497               udp0->src_port = s0->out2in.port;
1498               udp0->checksum = 0;
1499               udp_packets++;
1500             }
1501
1502           /* Accounting */
1503           nat44_session_update_counters (s0, now,
1504                                          vlib_buffer_length_in_chain (vm,
1505                                                                       b0));
1506           /* Per-user LRU list maintenance */
1507           nat44_session_update_lru (sm, s0, thread_index);
1508
1509         trace0:
1510           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1511                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1512             {
1513               snat_in2out_trace_t *t =
1514                 vlib_add_trace (vm, node, b0, sizeof (*t));
1515               t->is_slow_path = is_slow_path;
1516               t->sw_if_index = sw_if_index0;
1517               t->next_index = next0;
1518               t->session_index = ~0;
1519               if (s0)
1520                 t->session_index =
1521                   s0 - sm->per_thread_data[thread_index].sessions;
1522             }
1523
1524           pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1525
1526           /* verify speculative enqueue, maybe switch current next frame */
1527           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1528                                            to_next, n_left_to_next,
1529                                            bi0, next0);
1530         }
1531
1532       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1533     }
1534
1535   vlib_node_increment_counter (vm, stats_node_index,
1536                                SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
1537                                pkts_processed);
1538   vlib_node_increment_counter (vm, stats_node_index,
1539                                SNAT_IN2OUT_ERROR_TCP_PACKETS, tcp_packets);
1540   vlib_node_increment_counter (vm, stats_node_index,
1541                                SNAT_IN2OUT_ERROR_UDP_PACKETS, tcp_packets);
1542   vlib_node_increment_counter (vm, stats_node_index,
1543                                SNAT_IN2OUT_ERROR_ICMP_PACKETS, icmp_packets);
1544   vlib_node_increment_counter (vm, stats_node_index,
1545                                SNAT_IN2OUT_ERROR_OTHER_PACKETS,
1546                                other_packets);
1547   vlib_node_increment_counter (vm, stats_node_index,
1548                                SNAT_IN2OUT_ERROR_FRAGMENTS, fragments);
1549
1550   return frame->n_vectors;
1551 }
1552
1553 static uword
1554 snat_in2out_fast_path_fn (vlib_main_t * vm,
1555                           vlib_node_runtime_t * node, vlib_frame_t * frame)
1556 {
1557   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1558                                      0);
1559 }
1560
1561 /* *INDENT-OFF* */
1562 VLIB_REGISTER_NODE (snat_in2out_node) = {
1563   .function = snat_in2out_fast_path_fn,
1564   .name = "nat44-in2out",
1565   .vector_size = sizeof (u32),
1566   .format_trace = format_snat_in2out_trace,
1567   .type = VLIB_NODE_TYPE_INTERNAL,
1568
1569   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1570   .error_strings = snat_in2out_error_strings,
1571
1572   .runtime_data_bytes = sizeof (snat_runtime_t),
1573
1574   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1575
1576   /* edit / add dispositions here */
1577   .next_nodes = {
1578     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1579     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1580     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1581     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1582     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1583   },
1584 };
1585 /* *INDENT-ON* */
1586
1587 VLIB_NODE_FUNCTION_MULTIARCH (snat_in2out_node, snat_in2out_fast_path_fn);
1588
1589 static uword
1590 snat_in2out_output_fast_path_fn (vlib_main_t * vm,
1591                                  vlib_node_runtime_t * node,
1592                                  vlib_frame_t * frame)
1593 {
1594   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1595                                      1);
1596 }
1597
1598 /* *INDENT-OFF* */
1599 VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1600   .function = snat_in2out_output_fast_path_fn,
1601   .name = "nat44-in2out-output",
1602   .vector_size = sizeof (u32),
1603   .format_trace = format_snat_in2out_trace,
1604   .type = VLIB_NODE_TYPE_INTERNAL,
1605
1606   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1607   .error_strings = snat_in2out_error_strings,
1608
1609   .runtime_data_bytes = sizeof (snat_runtime_t),
1610
1611   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1612
1613   /* edit / add dispositions here */
1614   .next_nodes = {
1615     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1616     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1617     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1618     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1619     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1620   },
1621 };
1622 /* *INDENT-ON* */
1623
1624 VLIB_NODE_FUNCTION_MULTIARCH (snat_in2out_output_node,
1625                               snat_in2out_output_fast_path_fn);
1626
1627 static uword
1628 snat_in2out_slow_path_fn (vlib_main_t * vm,
1629                           vlib_node_runtime_t * node, vlib_frame_t * frame)
1630 {
1631   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1632                                      0);
1633 }
1634
1635 /* *INDENT-OFF* */
1636 VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1637   .function = snat_in2out_slow_path_fn,
1638   .name = "nat44-in2out-slowpath",
1639   .vector_size = sizeof (u32),
1640   .format_trace = format_snat_in2out_trace,
1641   .type = VLIB_NODE_TYPE_INTERNAL,
1642
1643   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1644   .error_strings = snat_in2out_error_strings,
1645
1646   .runtime_data_bytes = sizeof (snat_runtime_t),
1647
1648   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1649
1650   /* edit / add dispositions here */
1651   .next_nodes = {
1652     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1653     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1654     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1655     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1656     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1657   },
1658 };
1659 /* *INDENT-ON* */
1660
1661 VLIB_NODE_FUNCTION_MULTIARCH (snat_in2out_slowpath_node,
1662                               snat_in2out_slow_path_fn);
1663
1664 static uword
1665 snat_in2out_output_slow_path_fn (vlib_main_t * vm,
1666                                  vlib_node_runtime_t * node,
1667                                  vlib_frame_t * frame)
1668 {
1669   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1670                                      1);
1671 }
1672
1673 /* *INDENT-OFF* */
1674 VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1675   .function = snat_in2out_output_slow_path_fn,
1676   .name = "nat44-in2out-output-slowpath",
1677   .vector_size = sizeof (u32),
1678   .format_trace = format_snat_in2out_trace,
1679   .type = VLIB_NODE_TYPE_INTERNAL,
1680
1681   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1682   .error_strings = snat_in2out_error_strings,
1683
1684   .runtime_data_bytes = sizeof (snat_runtime_t),
1685
1686   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1687
1688   /* edit / add dispositions here */
1689   .next_nodes = {
1690     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1691     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1692     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1693     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1694     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1695   },
1696 };
1697 /* *INDENT-ON* */
1698
1699 VLIB_NODE_FUNCTION_MULTIARCH (snat_in2out_output_slowpath_node,
1700                               snat_in2out_output_slow_path_fn);
1701
1702 static uword
1703 nat44_in2out_reass_node_fn (vlib_main_t * vm,
1704                             vlib_node_runtime_t * node, vlib_frame_t * frame)
1705 {
1706   u32 n_left_from, *from, *to_next;
1707   snat_in2out_next_t next_index;
1708   u32 pkts_processed = 0, cached_fragments = 0;
1709   snat_main_t *sm = &snat_main;
1710   f64 now = vlib_time_now (vm);
1711   u32 thread_index = vm->thread_index;
1712   snat_main_per_thread_data_t *per_thread_data =
1713     &sm->per_thread_data[thread_index];
1714   u32 *fragments_to_drop = 0;
1715   u32 *fragments_to_loopback = 0;
1716
1717   from = vlib_frame_vector_args (frame);
1718   n_left_from = frame->n_vectors;
1719   next_index = node->cached_next_index;
1720
1721   while (n_left_from > 0)
1722     {
1723       u32 n_left_to_next;
1724
1725       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1726
1727       while (n_left_from > 0 && n_left_to_next > 0)
1728         {
1729           u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1730           vlib_buffer_t *b0;
1731           u32 next0;
1732           u8 cached0 = 0;
1733           ip4_header_t *ip0;
1734           nat_reass_ip4_t *reass0;
1735           udp_header_t *udp0;
1736           tcp_header_t *tcp0;
1737           icmp46_header_t *icmp0;
1738           snat_session_key_t key0;
1739           clib_bihash_kv_8_8_t kv0, value0;
1740           snat_session_t *s0 = 0;
1741           u16 old_port0, new_port0;
1742           ip_csum_t sum0;
1743
1744           /* speculatively enqueue b0 to the current next frame */
1745           bi0 = from[0];
1746           to_next[0] = bi0;
1747           from += 1;
1748           to_next += 1;
1749           n_left_from -= 1;
1750           n_left_to_next -= 1;
1751
1752           b0 = vlib_get_buffer (vm, bi0);
1753           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1754
1755           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1756           rx_fib_index0 =
1757             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1758                                                  sw_if_index0);
1759
1760           if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1761             {
1762               next0 = SNAT_IN2OUT_NEXT_DROP;
1763               b0->error = node->errors[SNAT_IN2OUT_ERROR_DROP_FRAGMENT];
1764               goto trace0;
1765             }
1766
1767           ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
1768           udp0 = ip4_next_header (ip0);
1769           tcp0 = (tcp_header_t *) udp0;
1770           icmp0 = (icmp46_header_t *) udp0;
1771           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1772
1773           reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1774                                                  ip0->dst_address,
1775                                                  ip0->fragment_id,
1776                                                  ip0->protocol,
1777                                                  1, &fragments_to_drop);
1778
1779           if (PREDICT_FALSE (!reass0))
1780             {
1781               next0 = SNAT_IN2OUT_NEXT_DROP;
1782               b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_REASS];
1783               nat_log_notice ("maximum reassemblies exceeded");
1784               goto trace0;
1785             }
1786
1787           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1788             {
1789               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1790                 {
1791                   next0 = icmp_in2out_slow_path
1792                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1793                      next0, now, thread_index, &s0);
1794
1795                   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP))
1796                     {
1797                       if (s0)
1798                         reass0->sess_index = s0 - per_thread_data->sessions;
1799                       else
1800                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1801                       nat_ip4_reass_get_frags (reass0,
1802                                                &fragments_to_loopback);
1803                     }
1804
1805                   goto trace0;
1806                 }
1807
1808               key0.addr = ip0->src_address;
1809               key0.port = udp0->src_port;
1810               key0.protocol = proto0;
1811               key0.fib_index = rx_fib_index0;
1812               kv0.key = key0.as_u64;
1813
1814               if (clib_bihash_search_8_8
1815                   (&per_thread_data->in2out, &kv0, &value0))
1816                 {
1817                   if (PREDICT_FALSE
1818                       (snat_not_translate
1819                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1820                         thread_index)))
1821                     goto trace0;
1822
1823                   next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1824                                      &s0, node, next0, thread_index, now);
1825
1826                   if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1827                     goto trace0;
1828
1829                   if (PREDICT_FALSE (!s0))
1830                     goto trace0;
1831
1832                   reass0->sess_index = s0 - per_thread_data->sessions;
1833                 }
1834               else
1835                 {
1836                   s0 = pool_elt_at_index (per_thread_data->sessions,
1837                                           value0.value);
1838                   reass0->sess_index = value0.value;
1839                 }
1840               nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1841             }
1842           else
1843             {
1844               if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1845                 {
1846                   if (nat_ip4_reass_add_fragment
1847                       (reass0, bi0, &fragments_to_drop))
1848                     {
1849                       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_FRAG];
1850                       nat_log_notice
1851                         ("maximum fragments per reassembly exceeded");
1852                       next0 = SNAT_IN2OUT_NEXT_DROP;
1853                       goto trace0;
1854                     }
1855                   cached0 = 1;
1856                   goto trace0;
1857                 }
1858               s0 = pool_elt_at_index (per_thread_data->sessions,
1859                                       reass0->sess_index);
1860             }
1861
1862           old_addr0 = ip0->src_address.as_u32;
1863           ip0->src_address = s0->out2in.addr;
1864           new_addr0 = ip0->src_address.as_u32;
1865           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1866
1867           sum0 = ip0->checksum;
1868           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1869                                  ip4_header_t,
1870                                  src_address /* changed member */ );
1871           ip0->checksum = ip_csum_fold (sum0);
1872
1873           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1874             {
1875               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1876                 {
1877                   old_port0 = tcp0->src_port;
1878                   tcp0->src_port = s0->out2in.port;
1879                   new_port0 = tcp0->src_port;
1880
1881                   sum0 = tcp0->checksum;
1882                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1883                                          ip4_header_t,
1884                                          dst_address /* changed member */ );
1885                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1886                                          ip4_header_t /* cheat */ ,
1887                                          length /* changed member */ );
1888                   tcp0->checksum = ip_csum_fold (sum0);
1889                 }
1890               else
1891                 {
1892                   old_port0 = udp0->src_port;
1893                   udp0->src_port = s0->out2in.port;
1894                   udp0->checksum = 0;
1895                 }
1896             }
1897
1898           /* Hairpinning */
1899           nat44_reass_hairpinning (sm, b0, ip0, s0->out2in.port,
1900                                    s0->ext_host_port, proto0, 0);
1901
1902           /* Accounting */
1903           nat44_session_update_counters (s0, now,
1904                                          vlib_buffer_length_in_chain (vm,
1905                                                                       b0));
1906           /* Per-user LRU list maintenance */
1907           nat44_session_update_lru (sm, s0, thread_index);
1908
1909         trace0:
1910           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1911                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1912             {
1913               nat44_reass_trace_t *t =
1914                 vlib_add_trace (vm, node, b0, sizeof (*t));
1915               t->cached = cached0;
1916               t->sw_if_index = sw_if_index0;
1917               t->next_index = next0;
1918             }
1919
1920           if (cached0)
1921             {
1922               n_left_to_next++;
1923               to_next--;
1924               cached_fragments++;
1925             }
1926           else
1927             {
1928               pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
1929
1930               /* verify speculative enqueue, maybe switch current next frame */
1931               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1932                                                to_next, n_left_to_next,
1933                                                bi0, next0);
1934             }
1935
1936           if (n_left_from == 0 && vec_len (fragments_to_loopback))
1937             {
1938               from = vlib_frame_vector_args (frame);
1939               u32 len = vec_len (fragments_to_loopback);
1940               if (len <= VLIB_FRAME_SIZE)
1941                 {
1942                   clib_memcpy_fast (from, fragments_to_loopback,
1943                                     sizeof (u32) * len);
1944                   n_left_from = len;
1945                   vec_reset_length (fragments_to_loopback);
1946                 }
1947               else
1948                 {
1949                   clib_memcpy_fast (from, fragments_to_loopback +
1950                                     (len - VLIB_FRAME_SIZE),
1951                                     sizeof (u32) * VLIB_FRAME_SIZE);
1952                   n_left_from = VLIB_FRAME_SIZE;
1953                   _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
1954                 }
1955             }
1956         }
1957
1958       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1959     }
1960
1961   vlib_node_increment_counter (vm, nat44_in2out_reass_node.index,
1962                                SNAT_IN2OUT_ERROR_PROCESSED_FRAGMENTS,
1963                                pkts_processed);
1964   vlib_node_increment_counter (vm, nat44_in2out_reass_node.index,
1965                                SNAT_IN2OUT_ERROR_CACHED_FRAGMENTS,
1966                                cached_fragments);
1967
1968   nat_send_all_to_node (vm, fragments_to_drop, node,
1969                         &node->errors[SNAT_IN2OUT_ERROR_DROP_FRAGMENT],
1970                         SNAT_IN2OUT_NEXT_DROP);
1971
1972   vec_free (fragments_to_drop);
1973   vec_free (fragments_to_loopback);
1974   return frame->n_vectors;
1975 }
1976
1977 /* *INDENT-OFF* */
1978 VLIB_REGISTER_NODE (nat44_in2out_reass_node) = {
1979   .function = nat44_in2out_reass_node_fn,
1980   .name = "nat44-in2out-reass",
1981   .vector_size = sizeof (u32),
1982   .format_trace = format_nat44_reass_trace,
1983   .type = VLIB_NODE_TYPE_INTERNAL,
1984
1985   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1986   .error_strings = snat_in2out_error_strings,
1987
1988   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1989   .next_nodes = {
1990     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1991     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1992     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1993     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1994     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1995   },
1996 };
1997 /* *INDENT-ON* */
1998
1999 VLIB_NODE_FUNCTION_MULTIARCH (nat44_in2out_reass_node,
2000                               nat44_in2out_reass_node_fn);
2001
2002 static uword
2003 snat_in2out_fast_static_map_fn (vlib_main_t * vm,
2004                                 vlib_node_runtime_t * node,
2005                                 vlib_frame_t * frame)
2006 {
2007   u32 n_left_from, *from, *to_next;
2008   snat_in2out_next_t next_index;
2009   u32 pkts_processed = 0;
2010   snat_main_t *sm = &snat_main;
2011   u32 stats_node_index;
2012
2013   stats_node_index = snat_in2out_fast_node.index;
2014
2015   from = vlib_frame_vector_args (frame);
2016   n_left_from = frame->n_vectors;
2017   next_index = node->cached_next_index;
2018
2019   while (n_left_from > 0)
2020     {
2021       u32 n_left_to_next;
2022
2023       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2024
2025       while (n_left_from > 0 && n_left_to_next > 0)
2026         {
2027           u32 bi0;
2028           vlib_buffer_t *b0;
2029           u32 next0;
2030           u32 sw_if_index0;
2031           ip4_header_t *ip0;
2032           ip_csum_t sum0;
2033           u32 new_addr0, old_addr0;
2034           u16 old_port0, new_port0;
2035           udp_header_t *udp0;
2036           tcp_header_t *tcp0;
2037           icmp46_header_t *icmp0;
2038           snat_session_key_t key0, sm0;
2039           u32 proto0;
2040           u32 rx_fib_index0;
2041
2042           /* speculatively enqueue b0 to the current next frame */
2043           bi0 = from[0];
2044           to_next[0] = bi0;
2045           from += 1;
2046           to_next += 1;
2047           n_left_from -= 1;
2048           n_left_to_next -= 1;
2049
2050           b0 = vlib_get_buffer (vm, bi0);
2051           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
2052
2053           ip0 = vlib_buffer_get_current (b0);
2054           udp0 = ip4_next_header (ip0);
2055           tcp0 = (tcp_header_t *) udp0;
2056           icmp0 = (icmp46_header_t *) udp0;
2057
2058           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2059           rx_fib_index0 =
2060             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
2061
2062           if (PREDICT_FALSE (ip0->ttl == 1))
2063             {
2064               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
2065               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
2066                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
2067                                            0);
2068               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
2069               goto trace0;
2070             }
2071
2072           proto0 = ip_proto_to_snat_proto (ip0->protocol);
2073
2074           if (PREDICT_FALSE (proto0 == ~0))
2075             goto trace0;
2076
2077           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
2078             {
2079               next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
2080                                    rx_fib_index0, node, next0, ~0, 0, 0);
2081               goto trace0;
2082             }
2083
2084           key0.addr = ip0->src_address;
2085           key0.protocol = proto0;
2086           key0.port = udp0->src_port;
2087           key0.fib_index = rx_fib_index0;
2088
2089           if (snat_static_mapping_match (sm, key0, &sm0, 0, 0, 0, 0, 0, 0))
2090             {
2091               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
2092               next0 = SNAT_IN2OUT_NEXT_DROP;
2093               goto trace0;
2094             }
2095
2096           new_addr0 = sm0.addr.as_u32;
2097           new_port0 = sm0.port;
2098           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
2099           old_addr0 = ip0->src_address.as_u32;
2100           ip0->src_address.as_u32 = new_addr0;
2101
2102           sum0 = ip0->checksum;
2103           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2104                                  ip4_header_t,
2105                                  src_address /* changed member */ );
2106           ip0->checksum = ip_csum_fold (sum0);
2107
2108           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
2109             {
2110               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
2111                 {
2112                   old_port0 = tcp0->src_port;
2113                   tcp0->src_port = new_port0;
2114
2115                   sum0 = tcp0->checksum;
2116                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2117                                          ip4_header_t,
2118                                          dst_address /* changed member */ );
2119                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
2120                                          ip4_header_t /* cheat */ ,
2121                                          length /* changed member */ );
2122                   mss_clamping (sm, tcp0, &sum0);
2123                   tcp0->checksum = ip_csum_fold (sum0);
2124                 }
2125               else
2126                 {
2127                   old_port0 = udp0->src_port;
2128                   udp0->src_port = new_port0;
2129                   udp0->checksum = 0;
2130                 }
2131             }
2132           else
2133             {
2134               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
2135                 {
2136                   sum0 = tcp0->checksum;
2137                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2138                                          ip4_header_t,
2139                                          dst_address /* changed member */ );
2140                   mss_clamping (sm, tcp0, &sum0);
2141                   tcp0->checksum = ip_csum_fold (sum0);
2142                 }
2143             }
2144
2145           /* Hairpinning */
2146           snat_hairpinning (sm, b0, ip0, udp0, tcp0, proto0, 0);
2147
2148         trace0:
2149           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
2150                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
2151             {
2152               snat_in2out_trace_t *t =
2153                 vlib_add_trace (vm, node, b0, sizeof (*t));
2154               t->sw_if_index = sw_if_index0;
2155               t->next_index = next0;
2156             }
2157
2158           pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
2159
2160           /* verify speculative enqueue, maybe switch current next frame */
2161           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
2162                                            to_next, n_left_to_next,
2163                                            bi0, next0);
2164         }
2165
2166       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2167     }
2168
2169   vlib_node_increment_counter (vm, stats_node_index,
2170                                SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
2171                                pkts_processed);
2172   return frame->n_vectors;
2173 }
2174
2175
2176 /* *INDENT-OFF* */
2177 VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
2178   .function = snat_in2out_fast_static_map_fn,
2179   .name = "nat44-in2out-fast",
2180   .vector_size = sizeof (u32),
2181   .format_trace = format_snat_in2out_fast_trace,
2182   .type = VLIB_NODE_TYPE_INTERNAL,
2183
2184   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
2185   .error_strings = snat_in2out_error_strings,
2186
2187   .runtime_data_bytes = sizeof (snat_runtime_t),
2188
2189   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
2190
2191   /* edit / add dispositions here */
2192   .next_nodes = {
2193     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
2194     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
2195     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2196     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2197     [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
2198   },
2199 };
2200 /* *INDENT-ON* */
2201
2202 VLIB_NODE_FUNCTION_MULTIARCH (snat_in2out_fast_node,
2203                               snat_in2out_fast_static_map_fn);
2204
2205 /*
2206  * fd.io coding-style-patch-verification: ON
2207  *
2208  * Local Variables:
2209  * eval: (c-set-style "gnu")
2210  * End:
2211  */