src/plugins/nat/in2out_ed.c

   1 /*
   2  * Copyright (c) 2018 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15 /**
  16  * @file
  17  * @brief NAT44 endpoint-dependent inside to outside network translation
  18  */
  19
  20 #include <vlib/vlib.h>
  21 #include <vnet/vnet.h>
  22 #include <vnet/pg/pg.h>
  23 #include <vnet/ip/ip.h>
  24 #include <vnet/ethernet/ethernet.h>
  25 #include <vnet/fib/ip4_fib.h>
  26 #include <vppinfra/error.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 #define foreach_nat_in2out_ed_error                       \
  34 _(UNSUPPORTED_PROTOCOL, "Unsupported protocol")         \
  35 _(IN2OUT_PACKETS, "Good in2out packets processed")      \
  36 _(OUT_OF_PORTS, "Out of ports")                         \
  37 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  38 _(MAX_SESSIONS_EXCEEDED, "Maximum sessions exceeded")   \
  39 _(DROP_FRAGMENT, "Drop fragment")                       \
  40 _(MAX_REASS, "Maximum reassemblies exceeded")           \
  41 _(MAX_FRAG, "Maximum fragments per reassembly exceeded")\
  42 _(NON_SYN, "non-SYN packet try to create session")
  43
  44 typedef enum
  45 {
  46 #define _(sym,str) NAT_IN2OUT_ED_ERROR_##sym,
  47   foreach_nat_in2out_ed_error
  48 #undef _
  49     NAT_IN2OUT_ED_N_ERROR,
  50 } nat_in2out_ed_error_t;
  51
  52 static char *nat_in2out_ed_error_strings[] = {
  53 #define _(sym,string) string,
  54   foreach_nat_in2out_ed_error
  55 #undef _
  56 };
  57
  58 typedef enum
  59 {
  60   NAT_IN2OUT_ED_NEXT_LOOKUP,
  61   NAT_IN2OUT_ED_NEXT_DROP,
  62   NAT_IN2OUT_ED_NEXT_ICMP_ERROR,
  63   NAT_IN2OUT_ED_NEXT_SLOW_PATH,
  64   NAT_IN2OUT_ED_NEXT_REASS,
  65   NAT_IN2OUT_ED_N_NEXT,
  66 } nat_in2out_ed_next_t;
  67
  68 typedef struct
  69 {
  70   u32 sw_if_index;
  71   u32 next_index;
  72   u32 session_index;
  73   u32 is_slow_path;
  74 } nat_in2out_ed_trace_t;
  75
  76 vlib_node_registration_t nat44_ed_in2out_node;
  77 vlib_node_registration_t nat44_ed_in2out_slowpath_node;
  78 vlib_node_registration_t nat44_ed_in2out_output_node;
  79 vlib_node_registration_t nat44_ed_in2out_output_slowpath_node;
  80 vlib_node_registration_t nat44_ed_in2out_reass_node;
  81
  82 static u8 *
  83 format_nat_in2out_ed_trace (u8 * s, va_list * args)
  84 {
  85   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  86   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  87   nat_in2out_ed_trace_t *t = va_arg (*args, nat_in2out_ed_trace_t *);
  88   char *tag;
  89
  90   tag =
  91     t->is_slow_path ? "NAT44_IN2OUT_ED_SLOW_PATH" :
  92     "NAT44_IN2OUT_ED_FAST_PATH";
  93
  94   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  95               t->sw_if_index, t->next_index, t->session_index);
  96
  97   return s;
  98 }
  99
 100 static_always_inline int
 101 icmp_get_ed_key (ip4_header_t * ip0, nat_ed_ses_key_t * p_key0)
 102 {
 103   icmp46_header_t *icmp0;
 104   nat_ed_ses_key_t key0;
 105   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 106   ip4_header_t *inner_ip0 = 0;
 107   void *l4_header = 0;
 108   icmp46_header_t *inner_icmp0;
 109
 110   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 111   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 112
 113   if (!icmp_is_error_message (icmp0))
 114     {
 115       key0.proto = IP_PROTOCOL_ICMP;
 116       key0.l_addr = ip0->src_address;
 117       key0.r_addr = ip0->dst_address;
 118       key0.l_port = echo0->identifier;
 119       key0.r_port = 0;
 120     }
 121   else
 122     {
 123       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 124       l4_header = ip4_next_header (inner_ip0);
 125       key0.proto = inner_ip0->protocol;
 126       key0.r_addr = inner_ip0->src_address;
 127       key0.l_addr = inner_ip0->dst_address;
 128       switch (ip_proto_to_snat_proto (inner_ip0->protocol))
 129         {
 130         case SNAT_PROTOCOL_ICMP:
 131           inner_icmp0 = (icmp46_header_t *) l4_header;
 132           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 133           key0.r_port = 0;
 134           key0.l_port = inner_echo0->identifier;
 135           break;
 136         case SNAT_PROTOCOL_UDP:
 137         case SNAT_PROTOCOL_TCP:
 138           key0.l_port = ((tcp_udp_header_t *) l4_header)->dst_port;
 139           key0.r_port = ((tcp_udp_header_t *) l4_header)->src_port;
 140           break;
 141         default:
 142           return NAT_IN2OUT_ED_ERROR_UNSUPPORTED_PROTOCOL;
 143         }
 144     }
 145   *p_key0 = key0;
 146   return 0;
 147 }
 148
 149 int
 150 nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
 151 {
 152   snat_main_t *sm = &snat_main;
 153   nat44_is_idle_session_ctx_t *ctx = arg;
 154   snat_session_t *s;
 155   u64 sess_timeout_time;
 156   nat_ed_ses_key_t ed_key;
 157   clib_bihash_kv_16_8_t ed_kv;
 158   int i;
 159   snat_address_t *a;
 160   snat_session_key_t key;
 161   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 162                                                        ctx->thread_index);
 163
 164   s = pool_elt_at_index (tsm->sessions, kv->value);
 165   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 166   if (ctx->now >= sess_timeout_time)
 167     {
 168       if (is_fwd_bypass_session (s))
 169         goto delete;
 170
 171       ed_key.l_addr = s->out2in.addr;
 172       ed_key.r_addr = s->ext_host_addr;
 173       ed_key.fib_index = s->out2in.fib_index;
 174       if (snat_is_unk_proto_session (s))
 175         {
 176           ed_key.proto = s->in2out.port;
 177           ed_key.r_port = 0;
 178           ed_key.l_port = 0;
 179         }
 180       else
 181         {
 182           ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
 183           ed_key.l_port = s->out2in.port;
 184           ed_key.r_port = s->ext_host_port;
 185         }
 186       ed_kv.key[0] = ed_key.as_u64[0];
 187       ed_kv.key[1] = ed_key.as_u64[1];
 188       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &ed_kv, 0))
 189         nat_log_warn ("out2in_ed key del failed");
 190
 191       if (snat_is_unk_proto_session (s))
 192         goto delete;
 193
 194       snat_ipfix_logging_nat44_ses_delete (s->in2out.addr.as_u32,
 195                                            s->out2in.addr.as_u32,
 196                                            s->in2out.protocol,
 197                                            s->in2out.port,
 198                                            s->out2in.port,
 199                                            s->in2out.fib_index);
 200
 201       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 202                              &s->in2out.addr, s->in2out.port,
 203                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 204                              &s->out2in.addr, s->out2in.port,
 205                              &s->ext_host_addr, s->ext_host_port,
 206                              s->in2out.protocol, is_twice_nat_session (s));
 207
 208       if (is_twice_nat_session (s))
 209         {
 210           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 211             {
 212               key.protocol = s->in2out.protocol;
 213               key.port = s->ext_host_nat_port;
 214               a = sm->twice_nat_addresses + i;
 215               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 216                 {
 217                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 218                                                       ctx->thread_index,
 219                                                       &key);
 220                   break;
 221                 }
 222             }
 223         }
 224
 225       if (snat_is_session_static (s))
 226         goto delete;
 227
 228       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 229                                           &s->out2in);
 230     delete:
 231       nat44_delete_session (sm, s, ctx->thread_index);
 232       return 1;
 233     }
 234
 235   return 0;
 236 }
 237
 238 static inline u32
 239 icmp_in2out_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 240                           ip4_header_t * ip0, icmp46_header_t * icmp0,
 241                           u32 sw_if_index0, u32 rx_fib_index0,
 242                           vlib_node_runtime_t * node, u32 next0, f64 now,
 243                           u32 thread_index, snat_session_t ** p_s0)
 244 {
 245   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 246                        next0, thread_index, p_s0, 0);
 247   snat_session_t *s0 = *p_s0;
 248   if (PREDICT_TRUE (next0 != NAT_IN2OUT_ED_NEXT_DROP && s0))
 249     {
 250       /* Accounting */
 251       nat44_session_update_counters (s0, now,
 252                                      vlib_buffer_length_in_chain
 253                                      (sm->vlib_main, b0));
 254       /* Per-user LRU list maintenance */
 255       nat44_session_update_lru (sm, s0, thread_index);
 256     }
 257   return next0;
 258 }
 259
 260 static u32
 261 slow_path_ed (snat_main_t * sm,
 262               vlib_buffer_t * b,
 263               u32 rx_fib_index,
 264               clib_bihash_kv_16_8_t * kv,
 265               snat_session_t ** sessionp,
 266               vlib_node_runtime_t * node, u32 next, u32 thread_index, f64 now,
 267               tcp_header_t * tcp)
 268 {
 269   snat_session_t *s = 0;
 270   snat_user_t *u;
 271   snat_session_key_t key0, key1;
 272   lb_nat_type_t lb = 0, is_sm = 0;
 273   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 274   nat_ed_ses_key_t *key = (nat_ed_ses_key_t *) kv->key;
 275   u32 proto = ip_proto_to_snat_proto (key->proto);
 276   nat_outside_fib_t *outside_fib;
 277   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 278   u8 identity_nat;
 279   fib_prefix_t pfx = {
 280     .fp_proto = FIB_PROTOCOL_IP4,
 281     .fp_len = 32,
 282     .fp_addr = {
 283                 .ip4.as_u32 = key->r_addr.as_u32,
 284                 },
 285   };
 286   nat44_is_idle_session_ctx_t ctx;
 287
 288   if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 289     {
 290       b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 291       nat_ipfix_logging_max_sessions (sm->max_translations);
 292       nat_log_notice ("maximum sessions exceeded");
 293       return NAT_IN2OUT_ED_NEXT_DROP;
 294     }
 295
 296   key0.addr = key->l_addr;
 297   key0.port = key->l_port;
 298   key1.protocol = key0.protocol = proto;
 299   key0.fib_index = rx_fib_index;
 300   key1.fib_index = sm->outside_fib_index;
 301   /* First try to match static mapping by local address and port */
 302   if (snat_static_mapping_match
 303       (sm, key0, &key1, 0, 0, 0, &lb, 0, &identity_nat))
 304     {
 305       /* Try to create dynamic translation */
 306       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index,
 307                                                thread_index, &key1,
 308                                                sm->port_per_thread,
 309                                                tsm->snat_thread_index))
 310         {
 311           nat_log_notice ("addresses exhausted");
 312           b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 313           return NAT_IN2OUT_ED_NEXT_DROP;
 314         }
 315     }
 316   else
 317     {
 318       if (PREDICT_FALSE (identity_nat))
 319         {
 320           *sessionp = s;
 321           return next;
 322         }
 323
 324       is_sm = 1;
 325     }
 326
 327   if (proto == SNAT_PROTOCOL_TCP)
 328     {
 329       if (!tcp_is_init (tcp))
 330         {
 331           b->error = node->errors[NAT_IN2OUT_ED_ERROR_NON_SYN];
 332           return NAT_IN2OUT_ED_NEXT_DROP;
 333         }
 334     }
 335
 336   u = nat_user_get_or_create (sm, &key->l_addr, rx_fib_index, thread_index);
 337   if (!u)
 338     {
 339       nat_log_warn ("create NAT user failed");
 340       if (!is_sm)
 341         snat_free_outside_address_and_port (sm->addresses,
 342                                             thread_index, &key1);
 343       return NAT_IN2OUT_ED_NEXT_DROP;
 344     }
 345
 346   s = nat_ed_session_alloc (sm, u, thread_index, now);
 347   if (!s)
 348     {
 349       nat44_delete_user_with_no_session (sm, u, thread_index);
 350       nat_log_warn ("create NAT session failed");
 351       if (!is_sm)
 352         snat_free_outside_address_and_port (sm->addresses,
 353                                             thread_index, &key1);
 354       return NAT_IN2OUT_ED_NEXT_DROP;
 355     }
 356
 357   user_session_increment (sm, u, is_sm);
 358   if (is_sm)
 359     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 360   if (lb)
 361     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 362   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 363   s->ext_host_addr = key->r_addr;
 364   s->ext_host_port = key->r_port;
 365   s->in2out = key0;
 366   s->out2in = key1;
 367   s->out2in.protocol = key0.protocol;
 368
 369   switch (vec_len (sm->outside_fibs))
 370     {
 371     case 0:
 372       s->out2in.fib_index = sm->outside_fib_index;
 373       break;
 374     case 1:
 375       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 376       break;
 377     default:
 378       /* *INDENT-OFF* */
 379       vec_foreach (outside_fib, sm->outside_fibs)
 380        {
 381           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 382           if (FIB_NODE_INDEX_INVALID != fei)
 383             {
 384               if (fib_entry_get_resolving_interface (fei) != ~0)
 385                 {
 386                   s->out2in.fib_index = outside_fib->fib_index;
 387                   break;
 388                 }
 389             }
 390         }
 391       /* *INDENT-ON* */
 392       break;
 393     }
 394
 395   /* Add to lookup tables */
 396   kv->value = s - tsm->sessions;
 397   ctx.now = now;
 398   ctx.thread_index = thread_index;
 399   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, kv,
 400                                                nat44_i2o_ed_is_idle_session_cb,
 401                                                &ctx))
 402     nat_log_notice ("in2out-ed key add failed");
 403
 404   make_ed_kv (kv, &key1.addr, &key->r_addr, key->proto, s->out2in.fib_index,
 405               key1.port, key->r_port);
 406   kv->value = s - tsm->sessions;
 407   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, kv,
 408                                                nat44_o2i_ed_is_idle_session_cb,
 409                                                &ctx))
 410     nat_log_notice ("out2in-ed key add failed");
 411
 412   *sessionp = s;
 413
 414   /* log NAT event */
 415   snat_ipfix_logging_nat44_ses_create (s->in2out.addr.as_u32,
 416                                        s->out2in.addr.as_u32,
 417                                        s->in2out.protocol,
 418                                        s->in2out.port,
 419                                        s->out2in.port, s->in2out.fib_index);
 420
 421   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 422                          &s->in2out.addr, s->in2out.port,
 423                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 424                          &s->out2in.addr, s->out2in.port,
 425                          &s->ext_host_addr, s->ext_host_port,
 426                          s->in2out.protocol, 0);
 427
 428   return next;
 429 }
 430
 431 static_always_inline int
 432 nat44_ed_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 433                         u32 sw_if_index, ip4_header_t * ip, u32 proto,
 434                         u32 rx_fib_index, u32 thread_index)
 435 {
 436   udp_header_t *udp = ip4_next_header (ip);
 437   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 438   clib_bihash_kv_16_8_t kv, value;
 439   snat_session_key_t key0, key1;
 440
 441   make_ed_kv (&kv, &ip->dst_address, &ip->src_address, ip->protocol,
 442               sm->outside_fib_index, udp->dst_port, udp->src_port);
 443
 444   /* NAT packet aimed at external address if */
 445   /* has active sessions */
 446   if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 447     {
 448       key0.addr = ip->dst_address;
 449       key0.port = udp->dst_port;
 450       key0.protocol = proto;
 451       key0.fib_index = sm->outside_fib_index;
 452       /* or is static mappings */
 453       if (!snat_static_mapping_match (sm, key0, &key1, 1, 0, 0, 0, 0, 0))
 454         return 0;
 455     }
 456   else
 457     return 0;
 458
 459   if (sm->forwarding_enabled)
 460     return 1;
 461
 462   return snat_not_translate_fast (sm, node, sw_if_index, ip, proto,
 463                                   rx_fib_index);
 464 }
 465
 466 static_always_inline int
 467 nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
 468                                       u32 thread_index, f64 now,
 469                                       vlib_main_t * vm, vlib_buffer_t * b)
 470 {
 471   nat_ed_ses_key_t key;
 472   clib_bihash_kv_16_8_t kv, value;
 473   udp_header_t *udp;
 474   snat_session_t *s = 0;
 475   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 476
 477   if (!sm->forwarding_enabled)
 478     return 0;
 479
 480   if (ip->protocol == IP_PROTOCOL_ICMP)
 481     {
 482       key.as_u64[0] = key.as_u64[1] = 0;
 483       if (icmp_get_ed_key (ip, &key))
 484         return 0;
 485       key.fib_index = 0;
 486       kv.key[0] = key.as_u64[0];
 487       kv.key[1] = key.as_u64[1];
 488     }
 489   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 490     {
 491       udp = ip4_next_header (ip);
 492       make_ed_kv (&kv, &ip->src_address, &ip->dst_address, ip->protocol, 0,
 493                   udp->src_port, udp->dst_port);
 494     }
 495   else
 496     {
 497       make_ed_kv (&kv, &ip->src_address, &ip->dst_address, ip->protocol, 0, 0,
 498                   0);
 499     }
 500
 501   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 502     {
 503       s = pool_elt_at_index (tsm->sessions, value.value);
 504       if (is_fwd_bypass_session (s))
 505         {
 506           if (ip->protocol == IP_PROTOCOL_TCP)
 507             {
 508               tcp_header_t *tcp = ip4_next_header (ip);
 509               if (nat44_set_tcp_session_state_i2o (sm, s, tcp, thread_index))
 510                 return 1;
 511             }
 512           /* Accounting */
 513           nat44_session_update_counters (s, now,
 514                                          vlib_buffer_length_in_chain (vm, b));
 515           /* Per-user LRU list maintenance */
 516           nat44_session_update_lru (sm, s, thread_index);
 517           return 1;
 518         }
 519       else
 520         return 0;
 521     }
 522
 523   return 0;
 524 }
 525
 526 static_always_inline int
 527 nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
 528                                        u8 proto, u16 src_port, u16 dst_port,
 529                                        u32 thread_index, u32 rx_sw_if_index,
 530                                        u32 tx_sw_if_index)
 531 {
 532   clib_bihash_kv_16_8_t kv, value;
 533   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 534   snat_interface_t *i;
 535   snat_session_t *s;
 536   u32 rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (rx_sw_if_index);
 537   u32 tx_fib_index = ip4_fib_table_get_index_for_sw_if_index (tx_sw_if_index);
 538
 539   /* src NAT check */
 540   make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto, tx_fib_index,
 541               src_port, dst_port);
 542   if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 543     {
 544       s = pool_elt_at_index (tsm->sessions, value.value);
 545       if (nat44_is_ses_closed (s))
 546         {
 547           nat_log_debug ("TCP close connection %U", format_snat_session,
 548                          &sm->per_thread_data[thread_index], s);
 549           nat_free_session_data (sm, s, thread_index);
 550           nat44_delete_session (sm, s, thread_index);
 551         }
 552       else
 553         s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
 554       return 1;
 555     }
 556
 557   /* dst NAT check */
 558   make_ed_kv (&kv, &ip->dst_address, &ip->src_address, proto, rx_fib_index,
 559               dst_port, src_port);
 560   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 561     {
 562       s = pool_elt_at_index (tsm->sessions, value.value);
 563       if (is_fwd_bypass_session (s))
 564         return 0;
 565
 566       /* hairpinning */
 567       /* *INDENT-OFF* */
 568       pool_foreach (i, sm->output_feature_interfaces,
 569       ({
 570         if ((nat_interface_is_inside (i)) && (rx_sw_if_index == i->sw_if_index))
 571            return 0;
 572       }));
 573       /* *INDENT-ON* */
 574       return 1;
 575     }
 576
 577   return 0;
 578 }
 579
 580 u32
 581 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 582                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 583                       u8 * p_proto, snat_session_key_t * p_value,
 584                       u8 * p_dont_translate, void *d, void *e)
 585 {
 586   icmp46_header_t *icmp;
 587   u32 sw_if_index;
 588   u32 rx_fib_index;
 589   nat_ed_ses_key_t key;
 590   snat_session_t *s = 0;
 591   u8 dont_translate = 0;
 592   clib_bihash_kv_16_8_t kv, value;
 593   u32 next = ~0;
 594   int err;
 595   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 596
 597   icmp = (icmp46_header_t *) ip4_next_header (ip);
 598   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 599   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 600
 601   key.as_u64[0] = key.as_u64[1] = 0;
 602   err = icmp_get_ed_key (ip, &key);
 603   if (err != 0)
 604     {
 605       b->error = node->errors[err];
 606       next = NAT_IN2OUT_ED_NEXT_DROP;
 607       goto out;
 608     }
 609   key.fib_index = rx_fib_index;
 610
 611   kv.key[0] = key.as_u64[0];
 612   kv.key[1] = key.as_u64[1];
 613
 614   if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 615     {
 616       if (vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0)
 617         {
 618           if (PREDICT_FALSE (nat44_ed_not_translate_output_feature (sm, ip,
 619                                                                     key.proto,
 620                                                                     key.
 621                                                                     l_port,
 622                                                                     key.
 623                                                                     r_port,
 624                                                                     thread_index,
 625                                                                     sw_if_index,
 626                                                                     vnet_buffer
 627                                                                     (b)->
 628                                                                     sw_if_index
 629                                                                     [VLIB_TX])))
 630             {
 631               dont_translate = 1;
 632               goto out;
 633             }
 634         }
 635       else
 636         {
 637           if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
 638                                                      ip, SNAT_PROTOCOL_ICMP,
 639                                                      rx_fib_index,
 640                                                      thread_index)))
 641             {
 642               dont_translate = 1;
 643               goto out;
 644             }
 645         }
 646
 647       if (PREDICT_FALSE (icmp_is_error_message (icmp)))
 648         {
 649           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 650           next = NAT_IN2OUT_ED_NEXT_DROP;
 651           goto out;
 652         }
 653
 654       next = slow_path_ed (sm, b, rx_fib_index, &kv, &s, node, next,
 655                            thread_index, vlib_time_now (sm->vlib_main), 0);
 656
 657       if (PREDICT_FALSE (next == NAT_IN2OUT_ED_NEXT_DROP))
 658         goto out;
 659
 660       if (!s)
 661         {
 662           dont_translate = 1;
 663           goto out;
 664         }
 665     }
 666   else
 667     {
 668       if (PREDICT_FALSE (icmp->type != ICMP4_echo_request &&
 669                          icmp->type != ICMP4_echo_reply &&
 670                          !icmp_is_error_message (icmp)))
 671         {
 672           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 673           next = NAT_IN2OUT_ED_NEXT_DROP;
 674           goto out;
 675         }
 676
 677       s = pool_elt_at_index (tsm->sessions, value.value);
 678     }
 679
 680   *p_proto = ip_proto_to_snat_proto (key.proto);
 681 out:
 682   if (s)
 683     *p_value = s->out2in;
 684   *p_dont_translate = dont_translate;
 685   if (d)
 686     *(snat_session_t **) d = s;
 687   return next;
 688 }
 689
 690 static snat_session_t *
 691 nat44_ed_in2out_unknown_proto (snat_main_t * sm,
 692                                vlib_buffer_t * b,
 693                                ip4_header_t * ip,
 694                                u32 rx_fib_index,
 695                                u32 thread_index,
 696                                f64 now,
 697                                vlib_main_t * vm, vlib_node_runtime_t * node)
 698 {
 699   clib_bihash_kv_8_8_t kv, value;
 700   clib_bihash_kv_16_8_t s_kv, s_value;
 701   snat_static_mapping_t *m;
 702   u32 old_addr, new_addr = 0;
 703   ip_csum_t sum;
 704   snat_user_t *u;
 705   dlist_elt_t *head, *elt;
 706   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 707   u32 elt_index, head_index, ses_index;
 708   snat_session_t *s;
 709   u32 outside_fib_index = sm->outside_fib_index;
 710   int i;
 711   u8 is_sm = 0;
 712   nat_outside_fib_t *outside_fib;
 713   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 714   fib_prefix_t pfx = {
 715     .fp_proto = FIB_PROTOCOL_IP4,
 716     .fp_len = 32,
 717     .fp_addr = {
 718                 .ip4.as_u32 = ip->dst_address.as_u32,
 719                 },
 720   };
 721
 722   switch (vec_len (sm->outside_fibs))
 723     {
 724     case 0:
 725       outside_fib_index = sm->outside_fib_index;
 726       break;
 727     case 1:
 728       outside_fib_index = sm->outside_fibs[0].fib_index;
 729       break;
 730     default:
 731       /* *INDENT-OFF* */
 732       vec_foreach (outside_fib, sm->outside_fibs)
 733         {
 734           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 735           if (FIB_NODE_INDEX_INVALID != fei)
 736             {
 737               if (fib_entry_get_resolving_interface (fei) != ~0)
 738                 {
 739                   outside_fib_index = outside_fib->fib_index;
 740                   break;
 741                 }
 742             }
 743         }
 744       /* *INDENT-ON* */
 745       break;
 746     }
 747   old_addr = ip->src_address.as_u32;
 748
 749   make_ed_kv (&s_kv, &ip->src_address, &ip->dst_address, ip->protocol,
 750               rx_fib_index, 0, 0);
 751
 752   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &s_kv, &s_value))
 753     {
 754       s = pool_elt_at_index (tsm->sessions, s_value.value);
 755       new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 756     }
 757   else
 758     {
 759       if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 760         {
 761           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 762           nat_ipfix_logging_max_sessions (sm->max_translations);
 763           nat_log_notice ("maximum sessions exceeded");
 764           return 0;
 765         }
 766
 767       u = nat_user_get_or_create (sm, &ip->src_address, rx_fib_index,
 768                                   thread_index);
 769       if (!u)
 770         {
 771           nat_log_warn ("create NAT user failed");
 772           return 0;
 773         }
 774
 775       make_sm_kv (&kv, &ip->src_address, 0, rx_fib_index, 0);
 776
 777       /* Try to find static mapping first */
 778       if (!clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 779         {
 780           m = pool_elt_at_index (sm->static_mappings, value.value);
 781           new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 782           is_sm = 1;
 783           goto create_ses;
 784         }
 785       /* Fallback to 3-tuple key */
 786       else
 787         {
 788           /* Choose same out address as for TCP/UDP session to same destination */
 789           head_index = u->sessions_per_user_list_head_index;
 790           head = pool_elt_at_index (tsm->list_pool, head_index);
 791           elt_index = head->next;
 792           if (PREDICT_FALSE (elt_index == ~0))
 793             ses_index = ~0;
 794           else
 795             {
 796               elt = pool_elt_at_index (tsm->list_pool, elt_index);
 797               ses_index = elt->value;
 798             }
 799
 800           while (ses_index != ~0)
 801             {
 802               s = pool_elt_at_index (tsm->sessions, ses_index);
 803               elt_index = elt->next;
 804               elt = pool_elt_at_index (tsm->list_pool, elt_index);
 805               ses_index = elt->value;
 806
 807               if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
 808                 {
 809                   new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 810
 811                   make_ed_kv (&s_kv, &s->out2in.addr, &ip->dst_address,
 812                               ip->protocol, outside_fib_index, 0, 0);
 813                   if (clib_bihash_search_16_8
 814                       (&tsm->out2in_ed, &s_kv, &s_value))
 815                     goto create_ses;
 816
 817                   break;
 818                 }
 819             }
 820
 821           for (i = 0; i < vec_len (sm->addresses); i++)
 822             {
 823               make_ed_kv (&s_kv, &sm->addresses[i].addr, &ip->dst_address,
 824                           ip->protocol, outside_fib_index, 0, 0);
 825               if (clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
 826                 {
 827                   new_addr = ip->src_address.as_u32 =
 828                     sm->addresses[i].addr.as_u32;
 829                   goto create_ses;
 830                 }
 831             }
 832           return 0;
 833         }
 834
 835     create_ses:
 836       s = nat_ed_session_alloc (sm, u, thread_index, now);
 837       if (!s)
 838         {
 839           nat44_delete_user_with_no_session (sm, u, thread_index);
 840           nat_log_warn ("create NAT session failed");
 841           return 0;
 842         }
 843
 844       s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
 845       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 846       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 847       s->out2in.addr.as_u32 = new_addr;
 848       s->out2in.fib_index = outside_fib_index;
 849       s->in2out.addr.as_u32 = old_addr;
 850       s->in2out.fib_index = rx_fib_index;
 851       s->in2out.port = s->out2in.port = ip->protocol;
 852       if (is_sm)
 853         s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 854       user_session_increment (sm, u, is_sm);
 855
 856       /* Add to lookup tables */
 857       make_ed_kv (&s_kv, &s->in2out.addr, &ip->dst_address, ip->protocol,
 858                   rx_fib_index, 0, 0);
 859       s_kv.value = s - tsm->sessions;
 860       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 861         nat_log_notice ("in2out key add failed");
 862
 863       make_ed_kv (&s_kv, &s->out2in.addr, &ip->dst_address, ip->protocol,
 864                   outside_fib_index, 0, 0);
 865       s_kv.value = s - tsm->sessions;
 866       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
 867         nat_log_notice ("out2in key add failed");
 868     }
 869
 870   /* Update IP checksum */
 871   sum = ip->checksum;
 872   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 873   ip->checksum = ip_csum_fold (sum);
 874
 875   /* Accounting */
 876   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b));
 877   /* Per-user LRU list maintenance */
 878   nat44_session_update_lru (sm, s, thread_index);
 879
 880   /* Hairpinning */
 881   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 882     nat44_ed_hairpinning_unknown_proto (sm, b, ip);
 883
 884   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 885     vnet_buffer (b)->sw_if_index[VLIB_TX] = outside_fib_index;
 886
 887   return s;
 888 }
 889
 890 static inline uword
 891 nat44_ed_in2out_node_fn_inline (vlib_main_t * vm,
 892                                 vlib_node_runtime_t * node,
 893                                 vlib_frame_t * frame, int is_slow_path,
 894                                 int is_output_feature)
 895 {
 896   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 897   nat_in2out_ed_next_t next_index;
 898   snat_main_t *sm = &snat_main;
 899   f64 now = vlib_time_now (vm);
 900   u32 thread_index = vm->thread_index;
 901   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 902
 903   stats_node_index = is_slow_path ? nat44_ed_in2out_slowpath_node.index :
 904     nat44_ed_in2out_node.index;
 905
 906   from = vlib_frame_vector_args (frame);
 907   n_left_from = frame->n_vectors;
 908   next_index = node->cached_next_index;
 909
 910   while (n_left_from > 0)
 911     {
 912       u32 n_left_to_next;
 913
 914       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 915
 916       while (n_left_from >= 4 && n_left_to_next >= 2)
 917         {
 918           u32 bi0, bi1;
 919           vlib_buffer_t *b0, *b1;
 920           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
 921             new_addr0, old_addr0;
 922           u32 next1, sw_if_index1, rx_fib_index1, iph_offset1 = 0, proto1,
 923             new_addr1, old_addr1;
 924           u16 old_port0, new_port0, old_port1, new_port1;
 925           ip4_header_t *ip0, *ip1;
 926           udp_header_t *udp0, *udp1;
 927           tcp_header_t *tcp0, *tcp1;
 928           icmp46_header_t *icmp0, *icmp1;
 929           snat_session_t *s0 = 0, *s1 = 0;
 930           clib_bihash_kv_16_8_t kv0, value0, kv1, value1;
 931           ip_csum_t sum0, sum1;
 932
 933           /* Prefetch next iteration. */
 934           {
 935             vlib_buffer_t *p2, *p3;
 936
 937             p2 = vlib_get_buffer (vm, from[2]);
 938             p3 = vlib_get_buffer (vm, from[3]);
 939
 940             vlib_prefetch_buffer_header (p2, LOAD);
 941             vlib_prefetch_buffer_header (p3, LOAD);
 942
 943             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 944             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 945           }
 946
 947           /* speculatively enqueue b0 and b1 to the current next frame */
 948           to_next[0] = bi0 = from[0];
 949           to_next[1] = bi1 = from[1];
 950           from += 2;
 951           to_next += 2;
 952           n_left_from -= 2;
 953           n_left_to_next -= 2;
 954
 955           b0 = vlib_get_buffer (vm, bi0);
 956           b1 = vlib_get_buffer (vm, bi1);
 957
 958           next0 = NAT_IN2OUT_ED_NEXT_LOOKUP;
 959
 960           if (is_output_feature)
 961             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
 962
 963           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 964                                   iph_offset0);
 965
 966           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 967           rx_fib_index0 =
 968             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 969                                                  sw_if_index0);
 970
 971           if (PREDICT_FALSE (ip0->ttl == 1))
 972             {
 973               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 974               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 975                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 976                                            0);
 977               next0 = NAT_IN2OUT_ED_NEXT_ICMP_ERROR;
 978               goto trace00;
 979             }
 980
 981           udp0 = ip4_next_header (ip0);
 982           tcp0 = (tcp_header_t *) udp0;
 983           icmp0 = (icmp46_header_t *) udp0;
 984           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 985
 986           if (is_slow_path)
 987             {
 988               if (PREDICT_FALSE (proto0 == ~0))
 989                 {
 990                   s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
 991                                                       rx_fib_index0,
 992                                                       thread_index, now, vm,
 993                                                       node);
 994                   if (!s0)
 995                     next0 = NAT_IN2OUT_ED_NEXT_DROP;
 996                   goto trace00;
 997                 }
 998
 999               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1000                 {
1001                   next0 = icmp_in2out_ed_slow_path
1002                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1003                      next0, now, thread_index, &s0);
1004                   goto trace00;
1005                 }
1006             }
1007           else
1008             {
1009               if (PREDICT_FALSE (proto0 == ~0))
1010                 {
1011                   next0 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1012                   goto trace00;
1013                 }
1014
1015               if (ip4_is_fragment (ip0))
1016                 {
1017                   next0 = NAT_IN2OUT_ED_NEXT_REASS;
1018                   goto trace00;
1019                 }
1020
1021               if (is_output_feature)
1022                 {
1023                   if (PREDICT_FALSE
1024                       (nat_not_translate_output_feature_fwd
1025                        (sm, ip0, thread_index, now, vm, b0)))
1026                     goto trace00;
1027                 }
1028
1029               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1030                 {
1031                   next0 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1032                   goto trace00;
1033                 }
1034             }
1035
1036           make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
1037                       ip0->protocol, rx_fib_index0, udp0->src_port,
1038                       udp0->dst_port);
1039
1040           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1041             {
1042               if (is_slow_path)
1043                 {
1044                   if (is_output_feature)
1045                     {
1046                       if (PREDICT_FALSE
1047                           (nat44_ed_not_translate_output_feature
1048                            (sm, ip0, ip0->protocol, udp0->src_port,
1049                             udp0->dst_port, thread_index, sw_if_index0,
1050                             vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1051                         goto trace00;
1052                     }
1053                   else
1054                     {
1055                       if (PREDICT_FALSE (nat44_ed_not_translate (sm, node,
1056                                                                  sw_if_index0,
1057                                                                  ip0, proto0,
1058                                                                  rx_fib_index0,
1059                                                                  thread_index)))
1060                         goto trace00;
1061                     }
1062
1063                   next0 =
1064                     slow_path_ed (sm, b0, rx_fib_index0, &kv0, &s0, node,
1065                                   next0, thread_index, now, tcp0);
1066
1067                   if (PREDICT_FALSE (next0 == NAT_IN2OUT_ED_NEXT_DROP))
1068                     goto trace00;
1069
1070                   if (PREDICT_FALSE (!s0))
1071                     goto trace00;
1072                 }
1073               else
1074                 {
1075                   next0 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1076                   goto trace00;
1077                 }
1078             }
1079           else
1080             {
1081               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1082             }
1083
1084           b0->flags |= VNET_BUFFER_F_IS_NATED;
1085
1086           if (!is_output_feature)
1087             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1088
1089           old_addr0 = ip0->src_address.as_u32;
1090           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1091           sum0 = ip0->checksum;
1092           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1093                                  src_address);
1094           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1095             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1096                                    s0->ext_host_addr.as_u32, ip4_header_t,
1097                                    dst_address);
1098           ip0->checksum = ip_csum_fold (sum0);
1099
1100           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1101             {
1102               old_port0 = tcp0->src_port;
1103               new_port0 = tcp0->src_port = s0->out2in.port;
1104
1105               sum0 = tcp0->checksum;
1106               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1107                                      dst_address);
1108               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1109                                      length);
1110               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1111                 {
1112                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1113                                          s0->ext_host_addr.as_u32,
1114                                          ip4_header_t, dst_address);
1115                   sum0 = ip_csum_update (sum0, tcp0->dst_port,
1116                                          s0->ext_host_port, ip4_header_t,
1117                                          length);
1118                   tcp0->dst_port = s0->ext_host_port;
1119                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1120                 }
1121               mss_clamping (sm, tcp0, &sum0);
1122               tcp0->checksum = ip_csum_fold (sum0);
1123               if (nat44_set_tcp_session_state_i2o
1124                   (sm, s0, tcp0, thread_index))
1125                 goto trace00;
1126             }
1127           else
1128             {
1129               udp0->src_port = s0->out2in.port;
1130               udp0->checksum = 0;
1131               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1132                 {
1133                   udp0->dst_port = s0->ext_host_port;
1134                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1135                 }
1136             }
1137
1138           /* Accounting */
1139           nat44_session_update_counters (s0, now,
1140                                          vlib_buffer_length_in_chain (vm,
1141                                                                       b0));
1142           /* Per-user LRU list maintenance */
1143           nat44_session_update_lru (sm, s0, thread_index);
1144
1145         trace00:
1146           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1147                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1148             {
1149               nat_in2out_ed_trace_t *t =
1150                 vlib_add_trace (vm, node, b0, sizeof (*t));
1151               t->is_slow_path = is_slow_path;
1152               t->sw_if_index = sw_if_index0;
1153               t->next_index = next0;
1154               t->session_index = ~0;
1155               if (s0)
1156                 t->session_index = s0 - tsm->sessions;
1157             }
1158
1159           pkts_processed += next0 != NAT_IN2OUT_ED_NEXT_DROP;
1160
1161
1162           next1 = NAT_IN2OUT_ED_NEXT_LOOKUP;
1163
1164           if (is_output_feature)
1165             iph_offset1 = vnet_buffer (b1)->ip.save_rewrite_length;
1166
1167           ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1168                                   iph_offset1);
1169
1170           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1171           rx_fib_index1 =
1172             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1173                                                  sw_if_index1);
1174
1175           if (PREDICT_FALSE (ip1->ttl == 1))
1176             {
1177               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1178               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1179                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1180                                            0);
1181               next1 = NAT_IN2OUT_ED_NEXT_ICMP_ERROR;
1182               goto trace01;
1183             }
1184
1185           udp1 = ip4_next_header (ip1);
1186           tcp1 = (tcp_header_t *) udp1;
1187           icmp1 = (icmp46_header_t *) udp1;
1188           proto1 = ip_proto_to_snat_proto (ip1->protocol);
1189
1190           if (is_slow_path)
1191             {
1192               if (PREDICT_FALSE (proto1 == ~0))
1193                 {
1194                   s1 = nat44_ed_in2out_unknown_proto (sm, b1, ip1,
1195                                                       rx_fib_index1,
1196                                                       thread_index, now, vm,
1197                                                       node);
1198                   if (!s1)
1199                     next1 = NAT_IN2OUT_ED_NEXT_DROP;
1200                   goto trace01;
1201                 }
1202
1203               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1204                 {
1205                   next1 = icmp_in2out_ed_slow_path
1206                     (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1207                      next1, now, thread_index, &s1);
1208                   goto trace01;
1209                 }
1210             }
1211           else
1212             {
1213               if (PREDICT_FALSE (proto1 == ~0))
1214                 {
1215                   next1 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1216                   goto trace01;
1217                 }
1218
1219               if (ip4_is_fragment (ip1))
1220                 {
1221                   next1 = NAT_IN2OUT_ED_NEXT_REASS;
1222                   goto trace01;
1223                 }
1224
1225               if (is_output_feature)
1226                 {
1227                   if (PREDICT_FALSE
1228                       (nat_not_translate_output_feature_fwd
1229                        (sm, ip1, thread_index, now, vm, b1)))
1230                     goto trace01;
1231                 }
1232
1233               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1234                 {
1235                   next1 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1236                   goto trace01;
1237                 }
1238             }
1239
1240           make_ed_kv (&kv1, &ip1->src_address, &ip1->dst_address,
1241                       ip1->protocol, rx_fib_index1, udp1->src_port,
1242                       udp1->dst_port);
1243
1244           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv1, &value1))
1245             {
1246               if (is_slow_path)
1247                 {
1248                   if (is_output_feature)
1249                     {
1250                       if (PREDICT_FALSE
1251                           (nat44_ed_not_translate_output_feature
1252                            (sm, ip1, ip1->protocol, udp1->src_port,
1253                             udp1->dst_port, thread_index, sw_if_index1,
1254                             vnet_buffer (b1)->sw_if_index[VLIB_TX])))
1255                         goto trace01;
1256                     }
1257                   else
1258                     {
1259                       if (PREDICT_FALSE (nat44_ed_not_translate (sm, node,
1260                                                                  sw_if_index1,
1261                                                                  ip1, proto1,
1262                                                                  rx_fib_index1,
1263                                                                  thread_index)))
1264                         goto trace01;
1265                     }
1266
1267                   next1 =
1268                     slow_path_ed (sm, b1, rx_fib_index1, &kv1, &s1, node,
1269                                   next1, thread_index, now, tcp1);
1270
1271                   if (PREDICT_FALSE (next1 == NAT_IN2OUT_ED_NEXT_DROP))
1272                     goto trace01;
1273
1274                   if (PREDICT_FALSE (!s1))
1275                     goto trace01;
1276                 }
1277               else
1278                 {
1279                   next1 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1280                   goto trace01;
1281                 }
1282             }
1283           else
1284             {
1285               s1 = pool_elt_at_index (tsm->sessions, value1.value);
1286             }
1287
1288           b1->flags |= VNET_BUFFER_F_IS_NATED;
1289
1290           if (!is_output_feature)
1291             vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1292
1293           old_addr1 = ip1->src_address.as_u32;
1294           new_addr1 = ip1->src_address.as_u32 = s1->out2in.addr.as_u32;
1295           sum1 = ip1->checksum;
1296           sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1297                                  src_address);
1298           if (PREDICT_FALSE (is_twice_nat_session (s1)))
1299             sum1 = ip_csum_update (sum1, ip1->dst_address.as_u32,
1300                                    s1->ext_host_addr.as_u32, ip4_header_t,
1301                                    dst_address);
1302           ip1->checksum = ip_csum_fold (sum1);
1303
1304           if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1305             {
1306               old_port1 = tcp1->src_port;
1307               new_port1 = tcp1->src_port = s1->out2in.port;
1308
1309               sum1 = tcp1->checksum;
1310               sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1311                                      dst_address);
1312               sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t,
1313                                      length);
1314               if (PREDICT_FALSE (is_twice_nat_session (s1)))
1315                 {
1316                   sum1 = ip_csum_update (sum1, ip1->dst_address.as_u32,
1317                                          s1->ext_host_addr.as_u32,
1318                                          ip4_header_t, dst_address);
1319                   sum1 = ip_csum_update (sum1, tcp1->dst_port,
1320                                          s1->ext_host_port, ip4_header_t,
1321                                          length);
1322                   tcp1->dst_port = s1->ext_host_port;
1323                   ip1->dst_address.as_u32 = s1->ext_host_addr.as_u32;
1324                 }
1325               tcp1->checksum = ip_csum_fold (sum1);
1326               mss_clamping (sm, tcp1, &sum1);
1327               if (nat44_set_tcp_session_state_i2o
1328                   (sm, s1, tcp1, thread_index))
1329                 goto trace01;
1330             }
1331           else
1332             {
1333               udp1->src_port = s1->out2in.port;
1334               udp1->checksum = 0;
1335               if (PREDICT_FALSE (is_twice_nat_session (s1)))
1336                 {
1337                   udp1->dst_port = s1->ext_host_port;
1338                   ip1->dst_address.as_u32 = s1->ext_host_addr.as_u32;
1339                 }
1340             }
1341
1342           /* Accounting */
1343           nat44_session_update_counters (s1, now,
1344                                          vlib_buffer_length_in_chain (vm,
1345                                                                       b1));
1346           /* Per-user LRU list maintenance */
1347           nat44_session_update_lru (sm, s1, thread_index);
1348
1349         trace01:
1350           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1351                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1352             {
1353               nat_in2out_ed_trace_t *t =
1354                 vlib_add_trace (vm, node, b1, sizeof (*t));
1355               t->is_slow_path = is_slow_path;
1356               t->sw_if_index = sw_if_index1;
1357               t->next_index = next1;
1358               t->session_index = ~0;
1359               if (s1)
1360                 t->session_index = s1 - tsm->sessions;
1361             }
1362
1363           pkts_processed += next1 != NAT_IN2OUT_ED_NEXT_DROP;
1364
1365           /* verify speculative enqueues, maybe switch current next frame */
1366           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1367                                            to_next, n_left_to_next,
1368                                            bi0, bi1, next0, next1);
1369         }
1370
1371       while (n_left_from > 0 && n_left_to_next > 0)
1372         {
1373           u32 bi0;
1374           vlib_buffer_t *b0;
1375           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
1376             new_addr0, old_addr0;
1377           u16 old_port0, new_port0;
1378           ip4_header_t *ip0;
1379           udp_header_t *udp0;
1380           tcp_header_t *tcp0;
1381           icmp46_header_t *icmp0;
1382           snat_session_t *s0 = 0;
1383           clib_bihash_kv_16_8_t kv0, value0;
1384           ip_csum_t sum0;
1385
1386           /* speculatively enqueue b0 to the current next frame */
1387           bi0 = from[0];
1388           to_next[0] = bi0;
1389           from += 1;
1390           to_next += 1;
1391           n_left_from -= 1;
1392           n_left_to_next -= 1;
1393
1394           b0 = vlib_get_buffer (vm, bi0);
1395           next0 = NAT_IN2OUT_ED_NEXT_LOOKUP;
1396
1397           if (is_output_feature)
1398             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
1399
1400           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1401                                   iph_offset0);
1402
1403           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1404           rx_fib_index0 =
1405             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1406                                                  sw_if_index0);
1407
1408           if (PREDICT_FALSE (ip0->ttl == 1))
1409             {
1410               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1411               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1412                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1413                                            0);
1414               next0 = NAT_IN2OUT_ED_NEXT_ICMP_ERROR;
1415               goto trace0;
1416             }
1417
1418           udp0 = ip4_next_header (ip0);
1419           tcp0 = (tcp_header_t *) udp0;
1420           icmp0 = (icmp46_header_t *) udp0;
1421           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1422
1423           if (is_slow_path)
1424             {
1425               if (PREDICT_FALSE (proto0 == ~0))
1426                 {
1427                   s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1428                                                       rx_fib_index0,
1429                                                       thread_index, now, vm,
1430                                                       node);
1431                   if (!s0)
1432                     next0 = NAT_IN2OUT_ED_NEXT_DROP;
1433                   goto trace0;
1434                 }
1435
1436               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1437                 {
1438                   next0 = icmp_in2out_ed_slow_path
1439                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1440                      next0, now, thread_index, &s0);
1441                   goto trace0;
1442                 }
1443             }
1444           else
1445             {
1446               if (PREDICT_FALSE (proto0 == ~0))
1447                 {
1448                   next0 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1449                   goto trace0;
1450                 }
1451
1452               if (ip4_is_fragment (ip0))
1453                 {
1454                   next0 = NAT_IN2OUT_ED_NEXT_REASS;
1455                   goto trace0;
1456                 }
1457
1458               if (is_output_feature)
1459                 {
1460                   if (PREDICT_FALSE
1461                       (nat_not_translate_output_feature_fwd
1462                        (sm, ip0, thread_index, now, vm, b0)))
1463                     goto trace0;
1464                 }
1465
1466               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1467                 {
1468                   next0 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1469                   goto trace0;
1470                 }
1471             }
1472
1473           make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
1474                       ip0->protocol, rx_fib_index0, udp0->src_port,
1475                       udp0->dst_port);
1476
1477           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1478             {
1479               if (is_slow_path)
1480                 {
1481                   if (is_output_feature)
1482                     {
1483                       if (PREDICT_FALSE
1484                           (nat44_ed_not_translate_output_feature
1485                            (sm, ip0, ip0->protocol, udp0->src_port,
1486                             udp0->dst_port, thread_index, sw_if_index0,
1487                             vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1488                         goto trace0;
1489                     }
1490                   else
1491                     {
1492                       if (PREDICT_FALSE (nat44_ed_not_translate (sm, node,
1493                                                                  sw_if_index0,
1494                                                                  ip0, proto0,
1495                                                                  rx_fib_index0,
1496                                                                  thread_index)))
1497                         goto trace0;
1498                     }
1499
1500                   next0 =
1501                     slow_path_ed (sm, b0, rx_fib_index0, &kv0, &s0, node,
1502                                   next0, thread_index, now, tcp0);
1503
1504                   if (PREDICT_FALSE (next0 == NAT_IN2OUT_ED_NEXT_DROP))
1505                     goto trace0;
1506
1507                   if (PREDICT_FALSE (!s0))
1508                     goto trace0;
1509                 }
1510               else
1511                 {
1512                   next0 = NAT_IN2OUT_ED_NEXT_SLOW_PATH;
1513                   goto trace0;
1514                 }
1515             }
1516           else
1517             {
1518               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1519             }
1520
1521           b0->flags |= VNET_BUFFER_F_IS_NATED;
1522
1523           if (!is_output_feature)
1524             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1525
1526           old_addr0 = ip0->src_address.as_u32;
1527           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1528           sum0 = ip0->checksum;
1529           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1530                                  src_address);
1531           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1532             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1533                                    s0->ext_host_addr.as_u32, ip4_header_t,
1534                                    dst_address);
1535           ip0->checksum = ip_csum_fold (sum0);
1536
1537           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1538             {
1539               old_port0 = tcp0->src_port;
1540               new_port0 = tcp0->src_port = s0->out2in.port;
1541
1542               sum0 = tcp0->checksum;
1543               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1544                                      dst_address);
1545               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1546                                      length);
1547               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1548                 {
1549                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1550                                          s0->ext_host_addr.as_u32,
1551                                          ip4_header_t, dst_address);
1552                   sum0 = ip_csum_update (sum0, tcp0->dst_port,
1553                                          s0->ext_host_port, ip4_header_t,
1554                                          length);
1555                   tcp0->dst_port = s0->ext_host_port;
1556                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1557                 }
1558               mss_clamping (sm, tcp0, &sum0);
1559               tcp0->checksum = ip_csum_fold (sum0);
1560               if (nat44_set_tcp_session_state_i2o
1561                   (sm, s0, tcp0, thread_index))
1562                 goto trace0;
1563             }
1564           else
1565             {
1566               udp0->src_port = s0->out2in.port;
1567               udp0->checksum = 0;
1568               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1569                 {
1570                   udp0->dst_port = s0->ext_host_port;
1571                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1572                 }
1573             }
1574
1575           /* Accounting */
1576           nat44_session_update_counters (s0, now,
1577                                          vlib_buffer_length_in_chain (vm,
1578                                                                       b0));
1579           /* Per-user LRU list maintenance */
1580           nat44_session_update_lru (sm, s0, thread_index);
1581
1582         trace0:
1583           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1584                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1585             {
1586               nat_in2out_ed_trace_t *t =
1587                 vlib_add_trace (vm, node, b0, sizeof (*t));
1588               t->is_slow_path = is_slow_path;
1589               t->sw_if_index = sw_if_index0;
1590               t->next_index = next0;
1591               t->session_index = ~0;
1592               if (s0)
1593                 t->session_index = s0 - tsm->sessions;
1594             }
1595
1596           pkts_processed += next0 != NAT_IN2OUT_ED_NEXT_DROP;
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                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1609                                pkts_processed);
1610   return frame->n_vectors;
1611 }
1612
1613 static uword
1614 nat44_ed_in2out_fast_path_fn (vlib_main_t * vm,
1615                               vlib_node_runtime_t * node,
1616                               vlib_frame_t * frame)
1617 {
1618   return nat44_ed_in2out_node_fn_inline (vm, node, frame, 0, 0);
1619 }
1620
1621 /* *INDENT-OFF* */
1622 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1623   .function = nat44_ed_in2out_fast_path_fn,
1624   .name = "nat44-ed-in2out",
1625   .vector_size = sizeof (u32),
1626   .format_trace = format_nat_in2out_ed_trace,
1627   .type = VLIB_NODE_TYPE_INTERNAL,
1628   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1629   .error_strings = nat_in2out_ed_error_strings,
1630   .runtime_data_bytes = sizeof (snat_runtime_t),
1631   .n_next_nodes = NAT_IN2OUT_ED_N_NEXT,
1632   .next_nodes = {
1633     [NAT_IN2OUT_ED_NEXT_DROP] = "error-drop",
1634     [NAT_IN2OUT_ED_NEXT_LOOKUP] = "ip4-lookup",
1635     [NAT_IN2OUT_ED_NEXT_SLOW_PATH] = "nat44-ed-in2out-slowpath",
1636     [NAT_IN2OUT_ED_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1637     [NAT_IN2OUT_ED_NEXT_REASS] = "nat44-ed-in2out-reass",
1638   },
1639 };
1640 /* *INDENT-ON* */
1641
1642 VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_in2out_node,
1643                               nat44_ed_in2out_fast_path_fn);
1644
1645 static uword
1646 nat44_ed_in2out_output_fast_path_fn (vlib_main_t * vm,
1647                                      vlib_node_runtime_t * node,
1648                                      vlib_frame_t * frame)
1649 {
1650   return nat44_ed_in2out_node_fn_inline (vm, node, frame, 0, 1);
1651 }
1652
1653 /* *INDENT-OFF* */
1654 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1655   .function = nat44_ed_in2out_output_fast_path_fn,
1656   .name = "nat44-ed-in2out-output",
1657   .vector_size = sizeof (u32),
1658   .format_trace = format_nat_in2out_ed_trace,
1659   .type = VLIB_NODE_TYPE_INTERNAL,
1660   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1661   .error_strings = nat_in2out_ed_error_strings,
1662   .runtime_data_bytes = sizeof (snat_runtime_t),
1663   .n_next_nodes = NAT_IN2OUT_ED_N_NEXT,
1664   .next_nodes = {
1665     [NAT_IN2OUT_ED_NEXT_DROP] = "error-drop",
1666     [NAT_IN2OUT_ED_NEXT_LOOKUP] = "interface-output",
1667     [NAT_IN2OUT_ED_NEXT_SLOW_PATH] = "nat44-ed-in2out-output-slowpath",
1668     [NAT_IN2OUT_ED_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1669     [NAT_IN2OUT_ED_NEXT_REASS] = "nat44-ed-in2out-reass-output",
1670   },
1671 };
1672 /* *INDENT-ON* */
1673
1674 VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_in2out_output_node,
1675                               nat44_ed_in2out_output_fast_path_fn);
1676
1677 static uword
1678 nat44_ed_in2out_slow_path_fn (vlib_main_t * vm,
1679                               vlib_node_runtime_t * node,
1680                               vlib_frame_t * frame)
1681 {
1682   return nat44_ed_in2out_node_fn_inline (vm, node, frame, 1, 0);
1683 }
1684
1685 /* *INDENT-OFF* */
1686 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1687   .function = nat44_ed_in2out_slow_path_fn,
1688   .name = "nat44-ed-in2out-slowpath",
1689   .vector_size = sizeof (u32),
1690   .format_trace = format_nat_in2out_ed_trace,
1691   .type = VLIB_NODE_TYPE_INTERNAL,
1692   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1693   .error_strings = nat_in2out_ed_error_strings,
1694   .runtime_data_bytes = sizeof (snat_runtime_t),
1695   .n_next_nodes = NAT_IN2OUT_ED_N_NEXT,
1696   .next_nodes = {
1697     [NAT_IN2OUT_ED_NEXT_DROP] = "error-drop",
1698     [NAT_IN2OUT_ED_NEXT_LOOKUP] = "ip4-lookup",
1699     [NAT_IN2OUT_ED_NEXT_SLOW_PATH] = "nat44-ed-in2out-slowpath",
1700     [NAT_IN2OUT_ED_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1701     [NAT_IN2OUT_ED_NEXT_REASS] = "nat44-ed-in2out-reass",
1702   },
1703 };
1704 /* *INDENT-ON* */
1705
1706 VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_in2out_slowpath_node,
1707                               nat44_ed_in2out_slow_path_fn);
1708
1709 static uword
1710 nat44_ed_in2out_output_slow_path_fn (vlib_main_t * vm,
1711                                      vlib_node_runtime_t * node,
1712                                      vlib_frame_t * frame)
1713 {
1714   return nat44_ed_in2out_node_fn_inline (vm, node, frame, 1, 1);
1715 }
1716
1717 /* *INDENT-OFF* */
1718 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1719   .function = nat44_ed_in2out_output_slow_path_fn,
1720   .name = "nat44-ed-in2out-output-slowpath",
1721   .vector_size = sizeof (u32),
1722   .format_trace = format_nat_in2out_ed_trace,
1723   .type = VLIB_NODE_TYPE_INTERNAL,
1724   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1725   .error_strings = nat_in2out_ed_error_strings,
1726   .runtime_data_bytes = sizeof (snat_runtime_t),
1727   .n_next_nodes = NAT_IN2OUT_ED_N_NEXT,
1728   .next_nodes = {
1729     [NAT_IN2OUT_ED_NEXT_DROP] = "error-drop",
1730     [NAT_IN2OUT_ED_NEXT_LOOKUP] = "interface-output",
1731     [NAT_IN2OUT_ED_NEXT_SLOW_PATH] = "nat44-ed-in2out-output-slowpath",
1732     [NAT_IN2OUT_ED_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1733     [NAT_IN2OUT_ED_NEXT_REASS] = "nat44-ed-in2out-reass",
1734   },
1735 };
1736 /* *INDENT-ON* */
1737
1738 VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_in2out_output_slowpath_node,
1739                               nat44_ed_in2out_output_slow_path_fn);
1740
1741 static inline uword
1742 nat44_ed_in2out_reass_node_fn_inline (vlib_main_t * vm,
1743                                       vlib_node_runtime_t * node,
1744                                       vlib_frame_t * frame,
1745                                       int is_output_feature)
1746 {
1747   u32 n_left_from, *from, *to_next;
1748   nat_in2out_ed_next_t next_index;
1749   u32 pkts_processed = 0;
1750   snat_main_t *sm = &snat_main;
1751   f64 now = vlib_time_now (vm);
1752   u32 thread_index = vm->thread_index;
1753   snat_main_per_thread_data_t *per_thread_data =
1754     &sm->per_thread_data[thread_index];
1755   u32 *fragments_to_drop = 0;
1756   u32 *fragments_to_loopback = 0;
1757
1758   from = vlib_frame_vector_args (frame);
1759   n_left_from = frame->n_vectors;
1760   next_index = node->cached_next_index;
1761
1762   while (n_left_from > 0)
1763     {
1764       u32 n_left_to_next;
1765
1766       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1767
1768       while (n_left_from > 0 && n_left_to_next > 0)
1769         {
1770           u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1771           u32 iph_offset0 = 0;
1772           vlib_buffer_t *b0;
1773           u32 next0;
1774           u8 cached0 = 0;
1775           ip4_header_t *ip0 = 0;
1776           nat_reass_ip4_t *reass0;
1777           udp_header_t *udp0;
1778           tcp_header_t *tcp0;
1779           icmp46_header_t *icmp0;
1780           clib_bihash_kv_16_8_t kv0, value0;
1781           snat_session_t *s0 = 0;
1782           u16 old_port0, new_port0;
1783           ip_csum_t sum0;
1784
1785           /* speculatively enqueue b0 to the current next frame */
1786           bi0 = from[0];
1787           to_next[0] = bi0;
1788           from += 1;
1789           to_next += 1;
1790           n_left_from -= 1;
1791           n_left_to_next -= 1;
1792
1793           b0 = vlib_get_buffer (vm, bi0);
1794
1795           next0 = NAT_IN2OUT_ED_NEXT_LOOKUP;
1796
1797           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1798           rx_fib_index0 =
1799             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1800                                                  sw_if_index0);
1801
1802           if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1803             {
1804               next0 = NAT_IN2OUT_ED_NEXT_DROP;
1805               b0->error = node->errors[NAT_IN2OUT_ED_ERROR_DROP_FRAGMENT];
1806               goto trace0;
1807             }
1808
1809           if (is_output_feature)
1810             iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
1811
1812           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1813                                   iph_offset0);
1814
1815           udp0 = ip4_next_header (ip0);
1816           tcp0 = (tcp_header_t *) udp0;
1817           icmp0 = (icmp46_header_t *) udp0;
1818           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1819
1820           reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1821                                                  ip0->dst_address,
1822                                                  ip0->fragment_id,
1823                                                  ip0->protocol,
1824                                                  1, &fragments_to_drop);
1825
1826           if (PREDICT_FALSE (!reass0))
1827             {
1828               next0 = NAT_IN2OUT_ED_NEXT_DROP;
1829               b0->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_REASS];
1830               nat_log_notice ("maximum reassemblies exceeded");
1831               goto trace0;
1832             }
1833
1834           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1835             {
1836               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1837                 {
1838                   if (is_output_feature)
1839                     {
1840                       if (PREDICT_FALSE
1841                           (nat_not_translate_output_feature_fwd
1842                            (sm, ip0, thread_index, now, vm, b0)))
1843                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1844                       goto trace0;
1845                     }
1846
1847                   next0 = icmp_in2out_ed_slow_path
1848                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1849                      next0, now, thread_index, &s0);
1850
1851                   if (PREDICT_TRUE (next0 != NAT_IN2OUT_ED_NEXT_DROP))
1852                     {
1853                       if (s0)
1854                         reass0->sess_index = s0 - per_thread_data->sessions;
1855                       else
1856                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1857                       nat_ip4_reass_get_frags (reass0,
1858                                                &fragments_to_loopback);
1859                     }
1860
1861                   goto trace0;
1862                 }
1863
1864               make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
1865                           ip0->protocol, rx_fib_index0, udp0->src_port,
1866                           udp0->dst_port);
1867
1868               if (clib_bihash_search_16_8
1869                   (&per_thread_data->in2out_ed, &kv0, &value0))
1870                 {
1871                   if (is_output_feature)
1872                     {
1873                       if (PREDICT_FALSE
1874                           (nat44_ed_not_translate_output_feature
1875                            (sm, ip0, ip0->protocol, udp0->src_port,
1876                             udp0->dst_port, thread_index, sw_if_index0,
1877                             vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1878                         {
1879                           reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1880                           nat_ip4_reass_get_frags (reass0,
1881                                                    &fragments_to_loopback);
1882                           goto trace0;
1883                         }
1884                     }
1885                   else
1886                     {
1887                       if (PREDICT_FALSE (nat44_ed_not_translate (sm, node,
1888                                                                  sw_if_index0,
1889                                                                  ip0, proto0,
1890                                                                  rx_fib_index0,
1891                                                                  thread_index)))
1892                         {
1893                           reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1894                           nat_ip4_reass_get_frags (reass0,
1895                                                    &fragments_to_loopback);
1896                           goto trace0;
1897                         }
1898                     }
1899
1900                   next0 = slow_path_ed (sm, b0, rx_fib_index0, &kv0,
1901                                         &s0, node, next0, thread_index, now,
1902                                         tcp0);
1903
1904                   if (PREDICT_FALSE (next0 == NAT_IN2OUT_ED_NEXT_DROP))
1905                     goto trace0;
1906
1907                   if (PREDICT_FALSE (!s0))
1908                     {
1909                       reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1910                       goto trace0;
1911                     }
1912
1913                   reass0->sess_index = s0 - per_thread_data->sessions;
1914                 }
1915               else
1916                 {
1917                   s0 = pool_elt_at_index (per_thread_data->sessions,
1918                                           value0.value);
1919                   reass0->sess_index = value0.value;
1920                 }
1921               nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1922             }
1923           else
1924             {
1925               if (reass0->flags & NAT_REASS_FLAG_ED_DONT_TRANSLATE)
1926                 goto trace0;
1927               if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1928                 {
1929                   if (nat_ip4_reass_add_fragment
1930                       (reass0, bi0, &fragments_to_drop))
1931                     {
1932                       b0->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_FRAG];
1933                       nat_log_notice
1934                         ("maximum fragments per reassembly exceeded");
1935                       next0 = NAT_IN2OUT_ED_NEXT_DROP;
1936                       goto trace0;
1937                     }
1938                   cached0 = 1;
1939                   goto trace0;
1940                 }
1941               s0 = pool_elt_at_index (per_thread_data->sessions,
1942                                       reass0->sess_index);
1943             }
1944
1945           old_addr0 = ip0->src_address.as_u32;
1946           ip0->src_address = s0->out2in.addr;
1947           new_addr0 = ip0->src_address.as_u32;
1948           if (!is_output_feature)
1949             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1950
1951           sum0 = ip0->checksum;
1952           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1953                                  ip4_header_t,
1954                                  src_address /* changed member */ );
1955           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1956             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1957                                    s0->ext_host_addr.as_u32, ip4_header_t,
1958                                    dst_address);
1959           ip0->checksum = ip_csum_fold (sum0);
1960
1961           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1962             {
1963               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1964                 {
1965                   old_port0 = tcp0->src_port;
1966                   tcp0->src_port = s0->out2in.port;
1967                   new_port0 = tcp0->src_port;
1968
1969                   sum0 = tcp0->checksum;
1970                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1971                                          ip4_header_t,
1972                                          dst_address /* changed member */ );
1973                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1974                                          ip4_header_t /* cheat */ ,
1975                                          length /* changed member */ );
1976                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1977                     {
1978                       sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1979                                              s0->ext_host_addr.as_u32,
1980                                              ip4_header_t, dst_address);
1981                       sum0 = ip_csum_update (sum0, tcp0->dst_port,
1982                                              s0->ext_host_port, ip4_header_t,
1983                                              length);
1984                       tcp0->dst_port = s0->ext_host_port;
1985                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1986                     }
1987                   tcp0->checksum = ip_csum_fold (sum0);
1988                 }
1989               else
1990                 {
1991                   old_port0 = udp0->src_port;
1992                   udp0->src_port = s0->out2in.port;
1993                   udp0->checksum = 0;
1994                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1995                     {
1996                       udp0->dst_port = s0->ext_host_port;
1997                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1998                     }
1999                 }
2000             }
2001
2002           /* Hairpinning */
2003           nat44_reass_hairpinning (sm, b0, ip0, s0->out2in.port,
2004                                    s0->ext_host_port, proto0, 1);
2005
2006           /* Accounting */
2007           nat44_session_update_counters (s0, now,
2008                                          vlib_buffer_length_in_chain (vm,
2009                                                                       b0));
2010           /* Per-user LRU list maintenance */
2011           nat44_session_update_lru (sm, s0, thread_index);
2012
2013         trace0:
2014           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
2015                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
2016             {
2017               nat44_reass_trace_t *t =
2018                 vlib_add_trace (vm, node, b0, sizeof (*t));
2019               t->cached = cached0;
2020               t->sw_if_index = sw_if_index0;
2021               t->next_index = next0;
2022             }
2023
2024           if (cached0)
2025             {
2026               n_left_to_next++;
2027               to_next--;
2028             }
2029           else
2030             {
2031               pkts_processed += next0 != NAT_IN2OUT_ED_NEXT_DROP;
2032
2033               /* verify speculative enqueue, maybe switch current next frame */
2034               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
2035                                                to_next, n_left_to_next,
2036                                                bi0, next0);
2037             }
2038
2039           if (n_left_from == 0 && vec_len (fragments_to_loopback))
2040             {
2041               from = vlib_frame_vector_args (frame);
2042               u32 len = vec_len (fragments_to_loopback);
2043               if (len <= VLIB_FRAME_SIZE)
2044                 {
2045                   clib_memcpy_fast (from, fragments_to_loopback,
2046                                     sizeof (u32) * len);
2047                   n_left_from = len;
2048                   vec_reset_length (fragments_to_loopback);
2049                 }
2050               else
2051                 {
2052                   clib_memcpy_fast (from, fragments_to_loopback +
2053                                     (len - VLIB_FRAME_SIZE),
2054                                     sizeof (u32) * VLIB_FRAME_SIZE);
2055                   n_left_from = VLIB_FRAME_SIZE;
2056                   _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
2057                 }
2058             }
2059         }
2060
2061       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2062     }
2063
2064   vlib_node_increment_counter (vm, nat44_ed_in2out_reass_node.index,
2065                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
2066                                pkts_processed);
2067
2068   nat_send_all_to_node (vm, fragments_to_drop, node,
2069                         &node->errors[NAT_IN2OUT_ED_ERROR_DROP_FRAGMENT],
2070                         NAT_IN2OUT_ED_NEXT_DROP);
2071
2072   vec_free (fragments_to_drop);
2073   vec_free (fragments_to_loopback);
2074   return frame->n_vectors;
2075 }
2076
2077 static uword
2078 nat44_ed_in2out_reass_node_fn (vlib_main_t * vm,
2079                                vlib_node_runtime_t * node,
2080                                vlib_frame_t * frame)
2081 {
2082   return nat44_ed_in2out_reass_node_fn_inline (vm, node, frame, 0);
2083 }
2084
2085 /* *INDENT-OFF* */
2086 VLIB_REGISTER_NODE (nat44_ed_in2out_reass_node) = {
2087   .function = nat44_ed_in2out_reass_node_fn,
2088   .name = "nat44-ed-in2out-reass",
2089   .vector_size = sizeof (u32),
2090   .format_trace = format_nat44_reass_trace,
2091   .type = VLIB_NODE_TYPE_INTERNAL,
2092   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
2093   .error_strings = nat_in2out_ed_error_strings,
2094   .n_next_nodes = NAT_IN2OUT_ED_N_NEXT,
2095   .next_nodes = {
2096     [NAT_IN2OUT_ED_NEXT_DROP] = "error-drop",
2097     [NAT_IN2OUT_ED_NEXT_LOOKUP] = "ip4-lookup",
2098     [NAT_IN2OUT_ED_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2099     [NAT_IN2OUT_ED_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2100     [NAT_IN2OUT_ED_NEXT_REASS] = "nat44-ed-in2out-reass",
2101   },
2102 };
2103 /* *INDENT-ON* */
2104
2105 VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_in2out_reass_node,
2106                               nat44_ed_in2out_reass_node_fn);
2107
2108 static uword
2109 nat44_ed_in2out_reass_output_node_fn (vlib_main_t * vm,
2110                                       vlib_node_runtime_t * node,
2111                                       vlib_frame_t * frame)
2112 {
2113   return nat44_ed_in2out_reass_node_fn_inline (vm, node, frame, 1);
2114 }
2115
2116 /* *INDENT-OFF* */
2117 VLIB_REGISTER_NODE (nat44_ed_in2out_reass_output_node) = {
2118   .function = nat44_ed_in2out_reass_output_node_fn,
2119   .name = "nat44-ed-in2out-reass-output",
2120   .vector_size = sizeof (u32),
2121   .format_trace = format_nat44_reass_trace,
2122   .type = VLIB_NODE_TYPE_INTERNAL,
2123   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
2124   .error_strings = nat_in2out_ed_error_strings,
2125   .n_next_nodes = NAT_IN2OUT_ED_N_NEXT,
2126   .next_nodes = {
2127     [NAT_IN2OUT_ED_NEXT_DROP] = "error-drop",
2128     [NAT_IN2OUT_ED_NEXT_LOOKUP] = "interface-output",
2129     [NAT_IN2OUT_ED_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2130     [NAT_IN2OUT_ED_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2131     [NAT_IN2OUT_ED_NEXT_REASS] = "nat44-ed-in2out-reass",
2132   },
2133 };
2134 /* *INDENT-ON* */
2135
2136 VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_in2out_reass_output_node,
2137                               nat44_ed_in2out_reass_output_node_fn);
2138
2139 /*
2140  * fd.io coding-style-patch-verification: ON
2141  *
2142  * Local Variables:
2143  * eval: (c-set-style "gnu")
2144  * End:
2145  */