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 <vnet/udp/udp.h>
  27 #include <vppinfra/error.h>
  28 #include <nat/nat.h>
  29 #include <nat/nat_ipfix_logging.h>
  30 #include <nat/nat_inlines.h>
  31 #include <nat/nat44/inlines.h>
  32 #include <nat/nat_syslog.h>
  33 #include <nat/nat_ha.h>
  34 #include <nat/nat44/ed_inlines.h>
  35 #include <nat/lib/nat_inlines.h>
  36
  37 static char *nat_in2out_ed_error_strings[] = {
  38 #define _(sym,string) string,
  39   foreach_nat_in2out_ed_error
  40 #undef _
  41 };
  42
  43 typedef struct
  44 {
  45   u32 sw_if_index;
  46   u32 next_index;
  47   u32 session_index;
  48   u32 is_slow_path;
  49 } nat_in2out_ed_trace_t;
  50
  51 static u8 *
  52 format_nat_in2out_ed_trace (u8 * s, va_list * args)
  53 {
  54   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  55   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  56   nat_in2out_ed_trace_t *t = va_arg (*args, nat_in2out_ed_trace_t *);
  57   char *tag;
  58
  59   tag =
  60     t->is_slow_path ? "NAT44_IN2OUT_ED_SLOW_PATH" :
  61     "NAT44_IN2OUT_ED_FAST_PATH";
  62
  63   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  64               t->sw_if_index, t->next_index, t->session_index);
  65
  66   return s;
  67 }
  68
  69 #ifndef CLIB_MARCH_VARIANT
  70 int
  71 nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  72 {
  73   snat_main_t *sm = &snat_main;
  74   nat44_is_idle_session_ctx_t *ctx = arg;
  75   snat_session_t *s;
  76   u64 sess_timeout_time;
  77   u8 proto;
  78   u16 r_port, l_port;
  79   ip4_address_t *l_addr, *r_addr;
  80   u32 fib_index;
  81   clib_bihash_kv_16_8_t ed_kv;
  82   int i;
  83   snat_address_t *a;
  84   snat_session_key_t key;
  85   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
  86                                                        ctx->thread_index);
  87
  88   ASSERT (ctx->thread_index == ed_value_get_thread_index (kv));
  89   s = pool_elt_at_index (tsm->sessions, ed_value_get_session_index (kv));
  90   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
  91   if (ctx->now >= sess_timeout_time)
  92     {
  93       if (is_fwd_bypass_session (s))
  94         goto delete;
  95
  96       l_addr = &s->out2in.addr;
  97       r_addr = &s->ext_host_addr;
  98       fib_index = s->out2in.fib_index;
  99       if (snat_is_unk_proto_session (s))
 100         {
 101           proto = s->in2out.port;
 102           r_port = 0;
 103           l_port = 0;
 104         }
 105       else
 106         {
 107           proto = nat_proto_to_ip_proto (s->in2out.protocol);
 108           l_port = s->out2in.port;
 109           r_port = s->ext_host_port;
 110         }
 111       make_ed_kv (l_addr, r_addr, proto, fib_index, l_port, r_port, ~0, ~0,
 112                   &ed_kv);
 113       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &ed_kv, 0))
 114         nat_elog_warn ("out2in_ed key del failed");
 115
 116       if (snat_is_unk_proto_session (s))
 117         goto delete;
 118
 119       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 120                                            s->in2out.addr.as_u32,
 121                                            s->out2in.addr.as_u32,
 122                                            s->in2out.protocol,
 123                                            s->in2out.port,
 124                                            s->out2in.port,
 125                                            s->in2out.fib_index);
 126
 127       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 128                              &s->in2out.addr, s->in2out.port,
 129                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 130                              &s->out2in.addr, s->out2in.port,
 131                              &s->ext_host_addr, s->ext_host_port,
 132                              s->in2out.protocol, is_twice_nat_session (s));
 133
 134       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 135                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 136                    ctx->thread_index);
 137
 138       if (is_twice_nat_session (s))
 139         {
 140           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 141             {
 142               key.protocol = s->in2out.protocol;
 143               key.port = s->ext_host_nat_port;
 144               a = sm->twice_nat_addresses + i;
 145               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 146                 {
 147                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 148                                                       ctx->thread_index,
 149                                                       &key);
 150                   break;
 151                 }
 152             }
 153         }
 154
 155       if (snat_is_session_static (s))
 156         goto delete;
 157
 158       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 159                                           &s->out2in);
 160     delete:
 161       nat_ed_session_delete (sm, s, ctx->thread_index, 1);
 162       return 1;
 163     }
 164
 165   return 0;
 166 }
 167 #endif
 168
 169 static inline u32
 170 icmp_in2out_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 171                           ip4_header_t * ip0, icmp46_header_t * icmp0,
 172                           u32 sw_if_index0, u32 rx_fib_index0,
 173                           vlib_node_runtime_t * node, u32 next0, f64 now,
 174                           u32 thread_index, snat_session_t ** p_s0)
 175 {
 176   vlib_main_t *vm = vlib_get_main ();
 177
 178   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 179                        next0, thread_index, p_s0, 0);
 180   snat_session_t *s0 = *p_s0;
 181   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
 182     {
 183       /* Accounting */
 184       nat44_session_update_counters (s0, now,
 185                                      vlib_buffer_length_in_chain
 186                                      (vm, b0), thread_index);
 187       /* Per-user LRU list maintenance */
 188       nat44_session_update_lru (sm, s0, thread_index);
 189     }
 190   return next0;
 191 }
 192
 193 static_always_inline u16
 194 snat_random_port (u16 min, u16 max)
 195 {
 196   snat_main_t *sm = &snat_main;
 197   return min + random_u32 (&sm->random_seed) /
 198     (random_u32_max () / (max - min + 1) + 1);
 199 }
 200
 201 static int
 202 nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
 203                             u32 nat_proto, u32 thread_index,
 204                             ip4_address_t r_addr, u16 r_port, u8 proto,
 205                             u16 port_per_thread, u32 snat_thread_index,
 206                             snat_session_t * s,
 207                             ip4_address_t * allocated_addr,
 208                             u16 * allocated_port,
 209                             clib_bihash_kv_16_8_t * out2in_ed_kv)
 210 {
 211   int i;
 212   snat_address_t *a, *ga = 0;
 213   u32 portnum;
 214   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 215
 216   const u16 port_thread_offset = (port_per_thread * snat_thread_index) + 1024;
 217
 218   for (i = 0; i < vec_len (sm->addresses); i++)
 219     {
 220       a = sm->addresses + i;
 221       switch (nat_proto)
 222         {
 223 #define _(N, j, n, unused)                                                    \
 224   case NAT_PROTOCOL_##N:                                                     \
 225     if (a->fib_index == rx_fib_index)                                         \
 226       {                                                                       \
 227         u16 port = snat_random_port (1, port_per_thread);                     \
 228         u16 attempts = port_per_thread;                                       \
 229         while (attempts > 0)                                                  \
 230           {                                                                   \
 231             --attempts;                                                       \
 232             portnum = port_thread_offset + port;                              \
 233             make_ed_kv (&a->addr, &r_addr, proto, s->out2in.fib_index,        \
 234                         clib_host_to_net_u16 (portnum), r_port, thread_index, \
 235                         s - tsm->sessions, out2in_ed_kv);                     \
 236             int rv = clib_bihash_add_del_16_8 (&sm->out2in_ed, out2in_ed_kv,  \
 237                                                2 /* is_add */);               \
 238             if (0 == rv)                                                      \
 239               {                                                               \
 240                 ++a->busy_##n##_port_refcounts[portnum];                      \
 241                 a->busy_##n##_ports_per_thread[thread_index]++;               \
 242                 a->busy_##n##_ports++;                                        \
 243                 *allocated_addr = a->addr;                                    \
 244                 *allocated_port = clib_host_to_net_u16 (portnum);             \
 245                 return 0;                                                     \
 246               }                                                               \
 247             port = (port + 1) % port_per_thread;                              \
 248           }                                                                   \
 249       }                                                                       \
 250     else if (a->fib_index == ~0)                                              \
 251       {                                                                       \
 252         ga = a;                                                               \
 253       }                                                                       \
 254     break;
 255
 256           foreach_nat_protocol;
 257         default:
 258           nat_elog_info ("unknown protocol");
 259           return 1;
 260         }
 261     }
 262
 263   if (ga)
 264     {
 265       /* fake fib_index to reuse macro */
 266       rx_fib_index = ~0;
 267       a = ga;
 268       switch (nat_proto)
 269         {
 270           foreach_nat_protocol;
 271         default:
 272           nat_elog_info ("unknown protocol");
 273           return 1;
 274         }
 275     }
 276
 277 #undef _
 278
 279   /* Totally out of translations to use... */
 280   snat_ipfix_logging_addresses_exhausted (thread_index, 0);
 281   return 1;
 282 }
 283
 284 static_always_inline u32
 285 nat_outside_fib_index_lookup (snat_main_t * sm, ip4_address_t addr)
 286 {
 287   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 288   nat_outside_fib_t *outside_fib;
 289   fib_prefix_t pfx = {
 290     .fp_proto = FIB_PROTOCOL_IP4,
 291     .fp_len = 32,
 292     .fp_addr = {.ip4.as_u32 = addr.as_u32,}
 293     ,
 294   };
 295   // TODO: multiple vrfs none can resolve addr
 296   /* *INDENT-OFF* */
 297   vec_foreach (outside_fib, sm->outside_fibs)
 298     {
 299       fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 300       if (FIB_NODE_INDEX_INVALID != fei)
 301         {
 302           if (fib_entry_get_resolving_interface (fei) != ~0)
 303             {
 304               return outside_fib->fib_index;
 305             }
 306         }
 307     }
 308   /* *INDENT-ON* */
 309   return ~0;
 310 }
 311
 312 static u32
 313 slow_path_ed (snat_main_t * sm,
 314               vlib_buffer_t * b,
 315               ip4_address_t l_addr,
 316               ip4_address_t r_addr,
 317               u16 l_port,
 318               u16 r_port,
 319               u8 proto,
 320               u32 rx_fib_index,
 321               snat_session_t ** sessionp,
 322               vlib_node_runtime_t * node, u32 next, u32 thread_index, f64 now)
 323 {
 324
 325   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 326   clib_bihash_kv_16_8_t out2in_ed_kv;
 327   nat44_is_idle_session_ctx_t ctx;
 328   snat_session_key_t key0, key1;
 329   ip4_address_t allocated_addr;
 330   u16 allocated_port;
 331   u32 tx_fib_index;
 332   u8 identity_nat;
 333
 334   u32 nat_proto = ip_proto_to_nat_proto (proto);
 335   snat_session_t *s = NULL;
 336   lb_nat_type_t lb = 0;
 337
 338   if (PREDICT_TRUE (nat_proto == NAT_PROTOCOL_TCP))
 339     {
 340       if (PREDICT_FALSE
 341           (!tcp_flags_is_init
 342            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 343         {
 344           b->error = node->errors[NAT_IN2OUT_ED_ERROR_NON_SYN];
 345           return NAT_NEXT_DROP;
 346         }
 347     }
 348
 349   if (PREDICT_FALSE
 350       (nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index)))
 351     {
 352       if (!nat_lru_free_one (sm, thread_index, now))
 353         {
 354           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 355           nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 356           nat_elog_notice ("maximum sessions exceeded");
 357           return NAT_NEXT_DROP;
 358         }
 359     }
 360
 361   key0.addr = l_addr;
 362   key0.port = l_port;
 363   key1.protocol = key0.protocol = nat_proto;
 364   key0.fib_index = rx_fib_index;
 365   key1.fib_index = sm->outside_fib_index;
 366   tx_fib_index = sm->outside_fib_index;
 367
 368   /* First try to match static mapping by local address and port */
 369   if (snat_static_mapping_match
 370       (sm, key0, &key1, 0, 0, 0, &lb, 0, &identity_nat))
 371     {
 372       s = nat_ed_session_alloc (sm, thread_index, now, proto);
 373       if (!s)
 374         {
 375           nat_elog_warn ("create NAT session failed");
 376           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 377           return NAT_NEXT_DROP;
 378         }
 379       switch (vec_len (sm->outside_fibs))
 380         {
 381         case 0:
 382           tx_fib_index = sm->outside_fib_index;
 383           break;
 384         case 1:
 385           tx_fib_index = sm->outside_fibs[0].fib_index;
 386           break;
 387         default:
 388           tx_fib_index = nat_outside_fib_index_lookup (sm, r_addr);
 389           break;
 390         }
 391
 392       s->out2in.fib_index = tx_fib_index;
 393       /* Try to create dynamic translation */
 394       if (nat_ed_alloc_addr_and_port (sm, rx_fib_index, nat_proto,
 395                                       thread_index, r_addr, r_port, proto,
 396                                       sm->port_per_thread,
 397                                       tsm->snat_thread_index, s,
 398                                       &allocated_addr,
 399                                       &allocated_port, &out2in_ed_kv))
 400         {
 401           nat_elog_notice ("addresses exhausted");
 402           b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 403           nat_ed_session_delete (sm, s, thread_index, 1);
 404           return NAT_NEXT_DROP;
 405         }
 406       key1.addr = allocated_addr;
 407       key1.port = allocated_port;
 408     }
 409   else
 410     {
 411       if (PREDICT_FALSE (identity_nat))
 412         {
 413           *sessionp = s;
 414           return next;
 415         }
 416       s = nat_ed_session_alloc (sm, thread_index, now, proto);
 417       if (!s)
 418         {
 419           nat_elog_warn ("create NAT session failed");
 420           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 421           return NAT_NEXT_DROP;
 422         }
 423       switch (vec_len (sm->outside_fibs))
 424         {
 425         case 0:
 426           tx_fib_index = sm->outside_fib_index;
 427           break;
 428         case 1:
 429           tx_fib_index = sm->outside_fibs[0].fib_index;
 430           break;
 431         default:
 432           tx_fib_index = nat_outside_fib_index_lookup (sm, r_addr);
 433           break;
 434         }
 435
 436       s->out2in.fib_index = tx_fib_index;
 437       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 438
 439       make_ed_kv (&key1.addr, &r_addr, proto,
 440                   s->out2in.fib_index, key1.port, r_port, thread_index,
 441                   s - tsm->sessions, &out2in_ed_kv);
 442       if (clib_bihash_add_or_overwrite_stale_16_8
 443           (&sm->out2in_ed, &out2in_ed_kv, nat44_o2i_ed_is_idle_session_cb,
 444            &ctx))
 445         nat_elog_notice ("out2in-ed key add failed");
 446     }
 447
 448   if (lb)
 449     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 450   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 451   s->ext_host_addr = r_addr;
 452   s->ext_host_port = r_port;
 453   s->in2out = key0;
 454   s->out2in = key1;
 455   s->out2in.fib_index = tx_fib_index;
 456   s->out2in.protocol = key0.protocol;
 457
 458   clib_bihash_kv_16_8_t in2out_ed_kv;
 459   make_ed_kv (&l_addr, &r_addr, proto, rx_fib_index, l_port, r_port,
 460               thread_index, s - tsm->sessions, &in2out_ed_kv);
 461   ctx.now = now;
 462   ctx.thread_index = thread_index;
 463   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &in2out_ed_kv,
 464                                                nat44_i2o_ed_is_idle_session_cb,
 465                                                &ctx))
 466     nat_elog_notice ("in2out-ed key add failed");
 467
 468   *sessionp = s;
 469
 470   /* log NAT event */
 471   snat_ipfix_logging_nat44_ses_create (thread_index,
 472                                        s->in2out.addr.as_u32,
 473                                        s->out2in.addr.as_u32,
 474                                        s->in2out.protocol,
 475                                        s->in2out.port,
 476                                        s->out2in.port, s->in2out.fib_index);
 477
 478   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 479                          &s->in2out.addr, s->in2out.port,
 480                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 481                          &s->out2in.addr, s->out2in.port,
 482                          &s->ext_host_addr, s->ext_host_port,
 483                          s->in2out.protocol, 0);
 484
 485   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 486                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 487                &s->ext_host_nat_addr, s->ext_host_nat_port,
 488                s->in2out.protocol, s->in2out.fib_index, s->flags,
 489                thread_index, 0);
 490
 491   return next;
 492 }
 493
 494 static_always_inline int
 495 nat44_ed_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 496                         u32 sw_if_index, ip4_header_t * ip, u32 proto,
 497                         u32 rx_fib_index, u32 thread_index)
 498 {
 499   udp_header_t *udp = ip4_next_header (ip);
 500   clib_bihash_kv_16_8_t kv, value;
 501   snat_session_key_t key0, key1;
 502
 503   make_ed_kv (&ip->dst_address, &ip->src_address, ip->protocol,
 504               sm->outside_fib_index, udp->dst_port, udp->src_port, ~0, ~0,
 505               &kv);
 506
 507   /* NAT packet aimed at external address if has active sessions */
 508   if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 509     {
 510       key0.addr = ip->dst_address;
 511       key0.port = udp->dst_port;
 512       key0.protocol = proto;
 513       key0.fib_index = sm->outside_fib_index;
 514       /* or is static mappings */
 515       if (!snat_static_mapping_match (sm, key0, &key1, 1, 0, 0, 0, 0, 0))
 516         return 0;
 517     }
 518   else
 519     return 0;
 520
 521   if (sm->forwarding_enabled)
 522     return 1;
 523
 524   return snat_not_translate_fast (sm, node, sw_if_index, ip, proto,
 525                                   rx_fib_index);
 526 }
 527
 528 static_always_inline int
 529 nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
 530                                       u32 thread_index, f64 now,
 531                                       vlib_main_t * vm, vlib_buffer_t * b)
 532 {
 533   clib_bihash_kv_16_8_t kv, value;
 534   snat_session_t *s = 0;
 535   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 536
 537   if (!sm->forwarding_enabled)
 538     return 0;
 539
 540   if (ip->protocol == IP_PROTOCOL_ICMP)
 541     {
 542       if (get_icmp_i2o_ed_key (b, ip, 0, ~0, ~0, 0, 0, 0, &kv))
 543         return 0;
 544     }
 545   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 546     {
 547       make_ed_kv (&ip->src_address, &ip->dst_address, ip->protocol, 0,
 548                   vnet_buffer (b)->ip.reass.l4_src_port,
 549                   vnet_buffer (b)->ip.reass.l4_dst_port, ~0, ~0, &kv);
 550     }
 551   else
 552     {
 553       make_ed_kv (&ip->src_address, &ip->dst_address, ip->protocol, 0, 0,
 554                   0, ~0, ~0, &kv);
 555     }
 556
 557   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 558     {
 559       ASSERT (thread_index == ed_value_get_thread_index (&value));
 560       s =
 561         pool_elt_at_index (tsm->sessions,
 562                            ed_value_get_session_index (&value));
 563       if (is_fwd_bypass_session (s))
 564         {
 565           if (ip->protocol == IP_PROTOCOL_TCP)
 566             {
 567               if (nat44_set_tcp_session_state_i2o
 568                   (sm, now, s, b, thread_index))
 569                 return 1;
 570             }
 571           /* Accounting */
 572           nat44_session_update_counters (s, now,
 573                                          vlib_buffer_length_in_chain (vm, b),
 574                                          thread_index);
 575           /* Per-user LRU list maintenance */
 576           nat44_session_update_lru (sm, s, thread_index);
 577           return 1;
 578         }
 579       else
 580         return 0;
 581     }
 582
 583   return 0;
 584 }
 585
 586 static_always_inline int
 587 nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
 588                                        u16 src_port, u16 dst_port,
 589                                        u32 thread_index, u32 rx_sw_if_index,
 590                                        u32 tx_sw_if_index)
 591 {
 592   clib_bihash_kv_16_8_t kv, value;
 593   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 594   snat_interface_t *i;
 595   snat_session_t *s;
 596   u32 rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (rx_sw_if_index);
 597   u32 tx_fib_index = ip4_fib_table_get_index_for_sw_if_index (tx_sw_if_index);
 598
 599   /* src NAT check */
 600   make_ed_kv (&ip->src_address, &ip->dst_address, ip->protocol,
 601               tx_fib_index, src_port, dst_port, ~0, ~0, &kv);
 602   if (!clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 603     {
 604       ASSERT (thread_index == ed_value_get_thread_index (&value));
 605       s =
 606         pool_elt_at_index (tsm->sessions,
 607                            ed_value_get_session_index (&value));
 608       if (nat44_is_ses_closed (s))
 609         {
 610           nat_free_session_data (sm, s, thread_index, 0);
 611           nat_ed_session_delete (sm, s, thread_index, 1);
 612         }
 613       else
 614         s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
 615       return 1;
 616     }
 617
 618   /* dst NAT check */
 619   make_ed_kv (&ip->dst_address, &ip->src_address, ip->protocol,
 620               rx_fib_index, dst_port, src_port, ~0, ~0, &kv);
 621   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 622     {
 623       ASSERT (thread_index == ed_value_get_thread_index (&value));
 624       s =
 625         pool_elt_at_index (tsm->sessions,
 626                            ed_value_get_session_index (&value));
 627       if (is_fwd_bypass_session (s))
 628         return 0;
 629
 630       /* hairpinning */
 631       /* *INDENT-OFF* */
 632       pool_foreach (i, sm->output_feature_interfaces,
 633       ({
 634         if ((nat_interface_is_inside (i)) && (rx_sw_if_index == i->sw_if_index))
 635            return 0;
 636       }));
 637       /* *INDENT-ON* */
 638       return 1;
 639     }
 640
 641   return 0;
 642 }
 643
 644 #ifndef CLIB_MARCH_VARIANT
 645 u32
 646 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 647                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 648                       u8 * p_proto, snat_session_key_t * p_value,
 649                       u8 * p_dont_translate, void *d, void *e)
 650 {
 651   u32 sw_if_index;
 652   u32 rx_fib_index;
 653   snat_session_t *s = 0;
 654   u8 dont_translate = 0;
 655   clib_bihash_kv_16_8_t kv, value;
 656   u32 next = ~0;
 657   int err;
 658   u16 l_port = 0, r_port = 0;   // initialize to workaround gcc warning
 659   vlib_main_t *vm = vlib_get_main ();
 660   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 661
 662   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 663   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 664
 665   err =
 666     get_icmp_i2o_ed_key (b, ip, rx_fib_index, ~0, ~0, p_proto, &l_port,
 667                          &r_port, &kv);
 668   if (err != 0)
 669     {
 670       b->error = node->errors[err];
 671       next = NAT_NEXT_DROP;
 672       goto out;
 673     }
 674
 675   if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 676     {
 677       if (vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0)
 678         {
 679           if (PREDICT_FALSE
 680               (nat44_ed_not_translate_output_feature
 681                (sm, ip, l_port, r_port, thread_index,
 682                 sw_if_index, vnet_buffer (b)->sw_if_index[VLIB_TX])))
 683             {
 684               dont_translate = 1;
 685               goto out;
 686             }
 687         }
 688       else
 689         {
 690           if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
 691                                                      ip, NAT_PROTOCOL_ICMP,
 692                                                      rx_fib_index,
 693                                                      thread_index)))
 694             {
 695               dont_translate = 1;
 696               goto out;
 697             }
 698         }
 699
 700       if (PREDICT_FALSE
 701           (icmp_type_is_error_message
 702            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 703         {
 704           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 705           next = NAT_NEXT_DROP;
 706           goto out;
 707         }
 708
 709       next =
 710         slow_path_ed (sm, b, ip->src_address, ip->dst_address, l_port, r_port,
 711                       ip->protocol, rx_fib_index, &s, node, next,
 712                       thread_index, vlib_time_now (vm));
 713
 714       if (PREDICT_FALSE (next == NAT_NEXT_DROP))
 715         goto out;
 716
 717       if (!s)
 718         {
 719           dont_translate = 1;
 720           goto out;
 721         }
 722     }
 723   else
 724     {
 725       if (PREDICT_FALSE
 726           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 727            ICMP4_echo_request
 728            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 729            ICMP4_echo_reply
 730            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 731                                            reass.icmp_type_or_tcp_flags)))
 732         {
 733           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 734           next = NAT_NEXT_DROP;
 735           goto out;
 736         }
 737
 738       ASSERT (thread_index == ed_value_get_thread_index (&value));
 739       s =
 740         pool_elt_at_index (tsm->sessions,
 741                            ed_value_get_session_index (&value));
 742     }
 743 out:
 744   if (s)
 745     *p_value = s->out2in;
 746   *p_dont_translate = dont_translate;
 747   if (d)
 748     *(snat_session_t **) d = s;
 749   return next;
 750 }
 751 #endif
 752
 753 static snat_session_t *
 754 nat44_ed_in2out_unknown_proto (snat_main_t * sm,
 755                                vlib_buffer_t * b,
 756                                ip4_header_t * ip,
 757                                u32 rx_fib_index,
 758                                u32 thread_index,
 759                                f64 now,
 760                                vlib_main_t * vm, vlib_node_runtime_t * node)
 761 {
 762   clib_bihash_kv_8_8_t kv, value;
 763   clib_bihash_kv_16_8_t s_kv, s_value;
 764   snat_static_mapping_t *m;
 765   u32 old_addr, new_addr = 0;
 766   ip_csum_t sum;
 767   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 768   snat_session_t *s;
 769   u32 outside_fib_index = sm->outside_fib_index;
 770   int i;
 771   u8 is_sm = 0;
 772
 773   switch (vec_len (sm->outside_fibs))
 774     {
 775     case 0:
 776       outside_fib_index = sm->outside_fib_index;
 777       break;
 778     case 1:
 779       outside_fib_index = sm->outside_fibs[0].fib_index;
 780       break;
 781     default:
 782       outside_fib_index = nat_outside_fib_index_lookup (sm, ip->dst_address);
 783       break;
 784     }
 785   old_addr = ip->src_address.as_u32;
 786
 787   make_ed_kv (&ip->src_address, &ip->dst_address, ip->protocol,
 788               rx_fib_index, 0, 0, ~0, ~0, &s_kv);
 789
 790   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &s_kv, &s_value))
 791     {
 792       ASSERT (thread_index == ed_value_get_thread_index (&s_value));
 793       s =
 794         pool_elt_at_index (tsm->sessions,
 795                            ed_value_get_session_index (&s_value));
 796       new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 797     }
 798   else
 799     {
 800       if (PREDICT_FALSE
 801           (nat44_ed_maximum_sessions_exceeded
 802            (sm, rx_fib_index, thread_index)))
 803         {
 804           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 805           nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 806           nat_elog_notice ("maximum sessions exceeded");
 807           return 0;
 808         }
 809
 810       make_sm_kv (&kv, &ip->src_address, 0, rx_fib_index, 0);
 811
 812       /* Try to find static mapping first */
 813       if (!clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 814         {
 815           m = pool_elt_at_index (sm->static_mappings, value.value);
 816           new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 817           is_sm = 1;
 818           goto create_ses;
 819         }
 820       else
 821         {
 822           /* *INDENT-OFF* */
 823           pool_foreach (s, tsm->sessions, {
 824             if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
 825               {
 826                 new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 827
 828                 make_ed_kv (&s->out2in.addr, &ip->dst_address, ip->protocol,
 829                             outside_fib_index, 0, 0, ~0, ~0, &s_kv);
 830                 if (clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
 831                   goto create_ses;
 832
 833                 break;
 834               }
 835           });
 836           /* *INDENT-ON* */
 837
 838           for (i = 0; i < vec_len (sm->addresses); i++)
 839             {
 840               make_ed_kv (&sm->addresses[i].addr, &ip->dst_address,
 841                           ip->protocol, outside_fib_index, 0, 0, ~0, ~0,
 842                           &s_kv);
 843               if (clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
 844                 {
 845                   new_addr = ip->src_address.as_u32 =
 846                     sm->addresses[i].addr.as_u32;
 847                   goto create_ses;
 848                 }
 849             }
 850           return 0;
 851         }
 852
 853     create_ses:
 854       s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
 855       if (!s)
 856         {
 857           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 858           nat_elog_warn ("create NAT session failed");
 859           return 0;
 860         }
 861
 862       s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
 863       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 864       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 865       s->out2in.addr.as_u32 = new_addr;
 866       s->out2in.fib_index = outside_fib_index;
 867       s->in2out.addr.as_u32 = old_addr;
 868       s->in2out.fib_index = rx_fib_index;
 869       s->in2out.port = s->out2in.port = ip->protocol;
 870       if (is_sm)
 871         s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 872
 873       /* Add to lookup tables */
 874       make_ed_kv (&s->in2out.addr, &ip->dst_address, ip->protocol,
 875                   rx_fib_index, 0, 0, thread_index, s - tsm->sessions, &s_kv);
 876       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 877         nat_elog_notice ("in2out key add failed");
 878
 879       make_ed_kv (&s->out2in.addr, &ip->dst_address, ip->protocol,
 880                   outside_fib_index, 0, 0, thread_index, s - tsm->sessions,
 881                   &s_kv);
 882       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &s_kv, 1))
 883         nat_elog_notice ("out2in key add failed");
 884     }
 885
 886   /* Update IP checksum */
 887   sum = ip->checksum;
 888   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 889   ip->checksum = ip_csum_fold (sum);
 890
 891   /* Accounting */
 892   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 893                                  thread_index);
 894   /* Per-user LRU list maintenance */
 895   nat44_session_update_lru (sm, s, thread_index);
 896
 897   /* Hairpinning */
 898   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 899     nat44_ed_hairpinning_unknown_proto (sm, b, ip);
 900
 901   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 902     vnet_buffer (b)->sw_if_index[VLIB_TX] = outside_fib_index;
 903
 904   return s;
 905 }
 906
 907 static inline uword
 908 nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 909                                           vlib_node_runtime_t * node,
 910                                           vlib_frame_t * frame,
 911                                           int is_output_feature)
 912 {
 913   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 914   nat_next_t next_index;
 915   snat_main_t *sm = &snat_main;
 916   f64 now = vlib_time_now (vm);
 917   u32 thread_index = vm->thread_index;
 918   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 919   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 920     0, def_slow;
 921
 922   def_slow = is_output_feature ? NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH :
 923     NAT_NEXT_IN2OUT_ED_SLOW_PATH;
 924
 925   stats_node_index = sm->ed_in2out_node_index;
 926
 927   from = vlib_frame_vector_args (frame);
 928   n_left_from = frame->n_vectors;
 929   next_index = node->cached_next_index;
 930
 931   while (n_left_from > 0)
 932     {
 933       u32 n_left_to_next;
 934
 935       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 936
 937       while (n_left_from > 0 && n_left_to_next > 0)
 938         {
 939           u32 bi0;
 940           vlib_buffer_t *b0;
 941           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
 942             new_addr0, old_addr0;
 943           u16 old_port0, new_port0;
 944           ip4_header_t *ip0;
 945           udp_header_t *udp0;
 946           tcp_header_t *tcp0;
 947           snat_session_t *s0 = 0;
 948           clib_bihash_kv_16_8_t kv0, value0;
 949           ip_csum_t sum0;
 950
 951           /* speculatively enqueue b0 to the current next frame */
 952           bi0 = from[0];
 953           to_next[0] = bi0;
 954           from += 1;
 955           to_next += 1;
 956           n_left_from -= 1;
 957           n_left_to_next -= 1;
 958
 959           b0 = vlib_get_buffer (vm, bi0);
 960
 961           if (is_output_feature)
 962             {
 963               vnet_feature_next (&vnet_buffer2 (b0)->nat.arc_next, b0);
 964               iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 965             }
 966
 967           next0 = vnet_buffer2 (b0)->nat.arc_next;
 968
 969           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 970                                   iph_offset0);
 971
 972           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 973           rx_fib_index0 =
 974             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 975                                                  sw_if_index0);
 976
 977           if (PREDICT_FALSE (ip0->ttl == 1))
 978             {
 979               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 980               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 981                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 982                                            0);
 983               next0 = NAT_NEXT_ICMP_ERROR;
 984               goto trace0;
 985             }
 986
 987           udp0 = ip4_next_header (ip0);
 988           tcp0 = (tcp_header_t *) udp0;
 989           proto0 = ip_proto_to_nat_proto (ip0->protocol);
 990
 991           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 992             {
 993               next0 = def_slow;
 994               goto trace0;
 995             }
 996
 997           if (is_output_feature)
 998             {
 999               if (PREDICT_FALSE (nat_not_translate_output_feature_fwd
1000                                  (sm, ip0, thread_index, now, vm, b0)))
1001                 goto trace0;
1002             }
1003
1004           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1005             {
1006               next0 = def_slow;
1007               goto trace0;
1008             }
1009
1010           make_ed_kv (&ip0->src_address, &ip0->dst_address,
1011                       ip0->protocol, rx_fib_index0,
1012                       vnet_buffer (b0)->ip.reass.l4_src_port,
1013                       vnet_buffer (b0)->ip.reass.l4_dst_port, ~0, ~0, &kv0);
1014
1015           // lookup for session
1016           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1017             {
1018               // session does not exist go slow path
1019               next0 = def_slow;
1020               goto trace0;
1021             }
1022           ASSERT (thread_index == ed_value_get_thread_index (&value0));
1023           s0 =
1024             pool_elt_at_index (tsm->sessions,
1025                                ed_value_get_session_index (&value0));
1026
1027           if (s0->tcp_closed_timestamp)
1028             {
1029               if (now >= s0->tcp_closed_timestamp)
1030                 {
1031                   // session is closed, go slow path
1032                   next0 = def_slow;
1033                 }
1034               else
1035                 {
1036                   // session in transitory timeout, drop
1037                   b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TCP_CLOSED];
1038                   next0 = NAT_NEXT_DROP;
1039                 }
1040               goto trace0;
1041             }
1042
1043           // drop if session expired
1044           u64 sess_timeout_time;
1045           sess_timeout_time = s0->last_heard +
1046             (f64) nat44_session_get_timeout (sm, s0);
1047           if (now >= sess_timeout_time)
1048             {
1049               nat_free_session_data (sm, s0, thread_index, 0);
1050               nat_ed_session_delete (sm, s0, thread_index, 1);
1051               // session is closed, go slow path
1052               next0 = def_slow;
1053               goto trace0;
1054             }
1055
1056           b0->flags |= VNET_BUFFER_F_IS_NATED;
1057
1058           if (!is_output_feature)
1059             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1060
1061           old_addr0 = ip0->src_address.as_u32;
1062           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1063           sum0 = ip0->checksum;
1064           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1065                                  src_address);
1066           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1067             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1068                                    s0->ext_host_addr.as_u32, ip4_header_t,
1069                                    dst_address);
1070           ip0->checksum = ip_csum_fold (sum0);
1071
1072           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1073
1074           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1075             {
1076               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1077                 {
1078                   new_port0 = udp0->src_port = s0->out2in.port;
1079                   sum0 = tcp0->checksum;
1080                   sum0 =
1081                     ip_csum_update (sum0, old_addr0, new_addr0,
1082                                     ip4_header_t, dst_address);
1083                   sum0 =
1084                     ip_csum_update (sum0, old_port0, new_port0,
1085                                     ip4_header_t, length);
1086                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1087                     {
1088                       sum0 =
1089                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1090                                         s0->ext_host_addr.as_u32,
1091                                         ip4_header_t, dst_address);
1092                       sum0 =
1093                         ip_csum_update (sum0,
1094                                         vnet_buffer (b0)->ip.
1095                                         reass.l4_dst_port, s0->ext_host_port,
1096                                         ip4_header_t, length);
1097                       tcp0->dst_port = s0->ext_host_port;
1098                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1099                     }
1100                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1101                   tcp0->checksum = ip_csum_fold (sum0);
1102                 }
1103               tcp_packets++;
1104               if (nat44_set_tcp_session_state_i2o
1105                   (sm, now, s0, b0, thread_index))
1106                 goto trace0;
1107             }
1108           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1109                    && udp0->checksum)
1110             {
1111               new_port0 = udp0->src_port = s0->out2in.port;
1112               sum0 = udp0->checksum;
1113               sum0 =
1114                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1115                                 dst_address);
1116               sum0 =
1117                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1118                                 length);
1119               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1120                 {
1121                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1122                                          s0->ext_host_addr.as_u32,
1123                                          ip4_header_t, dst_address);
1124                   sum0 =
1125                     ip_csum_update (sum0,
1126                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1127                                     s0->ext_host_port, ip4_header_t, length);
1128                   udp0->dst_port = s0->ext_host_port;
1129                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1130                 }
1131               udp0->checksum = ip_csum_fold (sum0);
1132               udp_packets++;
1133             }
1134           else
1135             {
1136               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1137                 {
1138                   new_port0 = udp0->src_port = s0->out2in.port;
1139                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1140                     {
1141                       udp0->dst_port = s0->ext_host_port;
1142                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1143                     }
1144                   udp_packets++;
1145                 }
1146             }
1147
1148           /* Accounting */
1149           nat44_session_update_counters (s0, now,
1150                                          vlib_buffer_length_in_chain
1151                                          (vm, b0), thread_index);
1152           /* Per-user LRU list maintenance */
1153           nat44_session_update_lru (sm, s0, thread_index);
1154
1155         trace0:
1156           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1157                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1158             {
1159               nat_in2out_ed_trace_t *t =
1160                 vlib_add_trace (vm, node, b0, sizeof (*t));
1161               t->sw_if_index = sw_if_index0;
1162               t->next_index = next0;
1163               t->is_slow_path = 0;
1164
1165               if (s0)
1166                 t->session_index = s0 - tsm->sessions;
1167               else
1168                 t->session_index = ~0;
1169             }
1170
1171           pkts_processed += next0 == vnet_buffer2 (b0)->nat.arc_next;
1172           /* verify speculative enqueue, maybe switch current next frame */
1173           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1174                                            to_next, n_left_to_next,
1175                                            bi0, next0);
1176         }
1177
1178       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1179     }
1180
1181   vlib_node_increment_counter (vm, stats_node_index,
1182                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1183                                pkts_processed);
1184   vlib_node_increment_counter (vm, stats_node_index,
1185                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1186   vlib_node_increment_counter (vm, stats_node_index,
1187                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1188   vlib_node_increment_counter (vm, stats_node_index,
1189                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1190                                icmp_packets);
1191   vlib_node_increment_counter (vm, stats_node_index,
1192                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1193                                other_packets);
1194   return frame->n_vectors;
1195 }
1196
1197 static inline uword
1198 nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
1199                                           vlib_node_runtime_t * node,
1200                                           vlib_frame_t * frame,
1201                                           int is_output_feature)
1202 {
1203   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
1204   nat_next_t next_index;
1205   snat_main_t *sm = &snat_main;
1206   f64 now = vlib_time_now (vm);
1207   u32 thread_index = vm->thread_index;
1208   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
1209   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets = 0;
1210
1211   stats_node_index = sm->ed_in2out_slowpath_node_index;
1212
1213   from = vlib_frame_vector_args (frame);
1214   n_left_from = frame->n_vectors;
1215   next_index = node->cached_next_index;
1216
1217   while (n_left_from > 0)
1218     {
1219       u32 n_left_to_next;
1220
1221       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1222
1223       while (n_left_from > 0 && n_left_to_next > 0)
1224         {
1225           u32 bi0;
1226           vlib_buffer_t *b0;
1227           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
1228             new_addr0, old_addr0;
1229           u16 old_port0, new_port0;
1230           ip4_header_t *ip0;
1231           udp_header_t *udp0;
1232           tcp_header_t *tcp0;
1233           icmp46_header_t *icmp0;
1234           snat_session_t *s0 = 0;
1235           clib_bihash_kv_16_8_t kv0, value0;
1236           ip_csum_t sum0;
1237
1238           /* speculatively enqueue b0 to the current next frame */
1239           bi0 = from[0];
1240           to_next[0] = bi0;
1241           from += 1;
1242           to_next += 1;
1243           n_left_from -= 1;
1244           n_left_to_next -= 1;
1245
1246           b0 = vlib_get_buffer (vm, bi0);
1247
1248           if (is_output_feature)
1249             iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1250
1251           next0 = vnet_buffer2 (b0)->nat.arc_next;
1252
1253           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1254                                   iph_offset0);
1255
1256           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1257           rx_fib_index0 =
1258             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1259                                                  sw_if_index0);
1260
1261           if (PREDICT_FALSE (ip0->ttl == 1))
1262             {
1263               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1264               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1265                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1266                                            0);
1267               next0 = NAT_NEXT_ICMP_ERROR;
1268               goto trace0;
1269             }
1270
1271           udp0 = ip4_next_header (ip0);
1272           tcp0 = (tcp_header_t *) udp0;
1273           icmp0 = (icmp46_header_t *) udp0;
1274           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1275
1276           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1277             {
1278               s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1279                                                   rx_fib_index0,
1280                                                   thread_index, now,
1281                                                   vm, node);
1282               if (!s0)
1283                 next0 = NAT_NEXT_DROP;
1284
1285               other_packets++;
1286               goto trace0;
1287             }
1288
1289           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1290             {
1291               next0 = icmp_in2out_ed_slow_path
1292                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
1293                  node, next0, now, thread_index, &s0);
1294               icmp_packets++;
1295               goto trace0;
1296             }
1297
1298           // move down
1299           make_ed_kv (&ip0->src_address, &ip0->dst_address,
1300                       ip0->protocol, rx_fib_index0,
1301                       vnet_buffer (b0)->ip.reass.l4_src_port,
1302                       vnet_buffer (b0)->ip.reass.l4_dst_port, ~0, ~0, &kv0);
1303
1304           if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1305             {
1306               ASSERT (thread_index == ed_value_get_thread_index (&value0));
1307               s0 =
1308                 pool_elt_at_index (tsm->sessions,
1309                                    ed_value_get_session_index (&value0));
1310
1311               if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
1312                 {
1313                   nat_free_session_data (sm, s0, thread_index, 0);
1314                   nat_ed_session_delete (sm, s0, thread_index, 1);
1315                   s0 = NULL;
1316                 }
1317             }
1318
1319           if (!s0)
1320             {
1321               if (is_output_feature)
1322                 {
1323                   if (PREDICT_FALSE
1324                       (nat44_ed_not_translate_output_feature
1325                        (sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
1326                         vnet_buffer (b0)->ip.reass.l4_dst_port, thread_index,
1327                         sw_if_index0,
1328                         vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1329                     goto trace0;
1330
1331                   /*
1332                    * Send DHCP packets to the ipv4 stack, or we won't
1333                    * be able to use dhcp client on the outside interface
1334                    */
1335                   if (PREDICT_FALSE
1336                       (proto0 == NAT_PROTOCOL_UDP
1337                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1338                            clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
1339                        && ip0->dst_address.as_u32 == 0xffffffff))
1340                     goto trace0;
1341                 }
1342               else
1343                 {
1344                   if (PREDICT_FALSE
1345                       (nat44_ed_not_translate
1346                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1347                         thread_index)))
1348                     goto trace0;
1349                 }
1350
1351               next0 =
1352                 slow_path_ed (sm, b0, ip0->src_address, ip0->dst_address,
1353                               vnet_buffer (b0)->ip.reass.l4_src_port,
1354                               vnet_buffer (b0)->ip.reass.l4_dst_port,
1355                               ip0->protocol, rx_fib_index0, &s0, node, next0,
1356                               thread_index, now);
1357
1358               if (PREDICT_FALSE (next0 == NAT_NEXT_DROP))
1359                 goto trace0;
1360
1361               if (PREDICT_FALSE (!s0))
1362                 goto trace0;
1363
1364             }
1365
1366           b0->flags |= VNET_BUFFER_F_IS_NATED;
1367
1368           if (!is_output_feature)
1369             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1370
1371           old_addr0 = ip0->src_address.as_u32;
1372           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1373           sum0 = ip0->checksum;
1374           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1375                                  src_address);
1376           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1377             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1378                                    s0->ext_host_addr.as_u32, ip4_header_t,
1379                                    dst_address);
1380           ip0->checksum = ip_csum_fold (sum0);
1381
1382           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1383
1384           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1385             {
1386               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1387                 {
1388                   new_port0 = udp0->src_port = s0->out2in.port;
1389                   sum0 = tcp0->checksum;
1390                   sum0 =
1391                     ip_csum_update (sum0, old_addr0, new_addr0,
1392                                     ip4_header_t, dst_address);
1393                   sum0 =
1394                     ip_csum_update (sum0, old_port0, new_port0,
1395                                     ip4_header_t, length);
1396                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1397                     {
1398                       sum0 =
1399                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1400                                         s0->ext_host_addr.as_u32,
1401                                         ip4_header_t, dst_address);
1402                       sum0 =
1403                         ip_csum_update (sum0,
1404                                         vnet_buffer (b0)->ip.
1405                                         reass.l4_dst_port, s0->ext_host_port,
1406                                         ip4_header_t, length);
1407                       tcp0->dst_port = s0->ext_host_port;
1408                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1409                     }
1410                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1411                   tcp0->checksum = ip_csum_fold (sum0);
1412                 }
1413               tcp_packets++;
1414               if (nat44_set_tcp_session_state_i2o
1415                   (sm, now, s0, b0, thread_index))
1416                 goto trace0;
1417             }
1418           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1419                    && udp0->checksum)
1420             {
1421               new_port0 = udp0->src_port = s0->out2in.port;
1422               sum0 = udp0->checksum;
1423               sum0 =
1424                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1425                                 dst_address);
1426               sum0 =
1427                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1428                                 length);
1429               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1430                 {
1431                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1432                                          s0->ext_host_addr.as_u32,
1433                                          ip4_header_t, dst_address);
1434                   sum0 =
1435                     ip_csum_update (sum0,
1436                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1437                                     s0->ext_host_port, ip4_header_t, length);
1438                   udp0->dst_port = s0->ext_host_port;
1439                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1440                 }
1441               udp0->checksum = ip_csum_fold (sum0);
1442               udp_packets++;
1443             }
1444           else
1445             {
1446               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1447                 {
1448                   new_port0 = udp0->src_port = s0->out2in.port;
1449                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1450                     {
1451                       udp0->dst_port = s0->ext_host_port;
1452                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1453                     }
1454                   udp_packets++;
1455                 }
1456             }
1457
1458           /* Accounting */
1459           nat44_session_update_counters (s0, now,
1460                                          vlib_buffer_length_in_chain
1461                                          (vm, b0), thread_index);
1462           /* Per-user LRU list maintenance */
1463           nat44_session_update_lru (sm, s0, thread_index);
1464
1465         trace0:
1466           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1467                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1468             {
1469               nat_in2out_ed_trace_t *t =
1470                 vlib_add_trace (vm, node, b0, sizeof (*t));
1471               t->sw_if_index = sw_if_index0;
1472               t->next_index = next0;
1473               t->is_slow_path = 1;
1474
1475               if (s0)
1476                 t->session_index = s0 - tsm->sessions;
1477               else
1478                 t->session_index = ~0;
1479             }
1480
1481           pkts_processed += next0 == vnet_buffer2 (b0)->nat.arc_next;
1482
1483           /* verify speculative enqueue, maybe switch current next frame */
1484           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1485                                            to_next, n_left_to_next,
1486                                            bi0, next0);
1487         }
1488
1489       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1490     }
1491
1492   vlib_node_increment_counter (vm, stats_node_index,
1493                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1494                                pkts_processed);
1495   vlib_node_increment_counter (vm, stats_node_index,
1496                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1497   vlib_node_increment_counter (vm, stats_node_index,
1498                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1499   vlib_node_increment_counter (vm, stats_node_index,
1500                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1501                                icmp_packets);
1502   vlib_node_increment_counter (vm, stats_node_index,
1503                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1504                                other_packets);
1505   return frame->n_vectors;
1506 }
1507
1508 VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
1509                                      vlib_node_runtime_t * node,
1510                                      vlib_frame_t * frame)
1511 {
1512   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
1513 }
1514
1515 /* *INDENT-OFF* */
1516 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1517   .name = "nat44-ed-in2out",
1518   .vector_size = sizeof (u32),
1519   .sibling_of = "nat-default",
1520   .format_trace = format_nat_in2out_ed_trace,
1521   .type = VLIB_NODE_TYPE_INTERNAL,
1522   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1523   .error_strings = nat_in2out_ed_error_strings,
1524   .runtime_data_bytes = sizeof (snat_runtime_t),
1525 };
1526 /* *INDENT-ON* */
1527
1528 VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
1529                                             vlib_node_runtime_t * node,
1530                                             vlib_frame_t * frame)
1531 {
1532   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
1533 }
1534
1535 /* *INDENT-OFF* */
1536 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1537   .name = "nat44-ed-in2out-output",
1538   .vector_size = sizeof (u32),
1539   .sibling_of = "nat-default",
1540   .format_trace = format_nat_in2out_ed_trace,
1541   .type = VLIB_NODE_TYPE_INTERNAL,
1542   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1543   .error_strings = nat_in2out_ed_error_strings,
1544   .runtime_data_bytes = sizeof (snat_runtime_t),
1545 };
1546 /* *INDENT-ON* */
1547
1548 VLIB_NODE_FN (nat44_ed_in2out_slowpath_node) (vlib_main_t * vm,
1549                                               vlib_node_runtime_t *
1550                                               node, vlib_frame_t * frame)
1551 {
1552   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 0);
1553 }
1554
1555 /* *INDENT-OFF* */
1556 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1557   .name = "nat44-ed-in2out-slowpath",
1558   .vector_size = sizeof (u32),
1559   .sibling_of = "nat-default",
1560   .format_trace = format_nat_in2out_ed_trace,
1561   .type = VLIB_NODE_TYPE_INTERNAL,
1562   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1563   .error_strings = nat_in2out_ed_error_strings,
1564   .runtime_data_bytes = sizeof (snat_runtime_t),
1565 };
1566 /* *INDENT-ON* */
1567
1568 VLIB_NODE_FN (nat44_ed_in2out_output_slowpath_node) (vlib_main_t * vm,
1569                                                      vlib_node_runtime_t
1570                                                      * node,
1571                                                      vlib_frame_t * frame)
1572 {
1573   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 1);
1574 }
1575
1576 /* *INDENT-OFF* */
1577 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1578   .name = "nat44-ed-in2out-output-slowpath",
1579   .vector_size = sizeof (u32),
1580   .sibling_of = "nat-default",
1581   .format_trace = format_nat_in2out_ed_trace,
1582   .type = VLIB_NODE_TYPE_INTERNAL,
1583   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1584   .error_strings = nat_in2out_ed_error_strings,
1585   .runtime_data_bytes = sizeof (snat_runtime_t),
1586 };
1587 /* *INDENT-ON* */
1588
1589 static u8 *
1590 format_nat_pre_trace (u8 * s, va_list * args)
1591 {
1592   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1593   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1594   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1595   return format (s, "in2out next_index %d arc_next_index %d", t->next_index,
1596                  t->arc_next_index);
1597 }
1598
1599 VLIB_NODE_FN (nat_pre_in2out_node)
1600   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1601 {
1602   return nat_pre_node_fn_inline (vm, node, frame,
1603                                  NAT_NEXT_IN2OUT_ED_FAST_PATH);
1604 }
1605
1606 /* *INDENT-OFF* */
1607 VLIB_REGISTER_NODE (nat_pre_in2out_node) = {
1608   .name = "nat-pre-in2out",
1609   .vector_size = sizeof (u32),
1610   .sibling_of = "nat-default",
1611   .format_trace = format_nat_pre_trace,
1612   .type = VLIB_NODE_TYPE_INTERNAL,
1613   .n_errors = 0,
1614 };
1615 /* *INDENT-ON* */
1616
1617 /*
1618  * fd.io coding-style-patch-verification: ON
1619  *
1620  * Local Variables:
1621  * eval: (c-set-style "gnu")
1622  * End:
1623  */