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_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
  85                                                        ctx->thread_index);
  86
  87   ASSERT (ctx->thread_index == ed_value_get_thread_index (kv));
  88   s = pool_elt_at_index (tsm->sessions, ed_value_get_session_index (kv));
  89   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
  90   if (ctx->now >= sess_timeout_time)
  91     {
  92       if (is_fwd_bypass_session (s))
  93         goto delete;
  94
  95       l_addr = &s->out2in.addr;
  96       r_addr = &s->ext_host_addr;
  97       fib_index = s->out2in.fib_index;
  98       if (snat_is_unk_proto_session (s))
  99         {
 100           proto = s->in2out.port;
 101           r_port = 0;
 102           l_port = 0;
 103         }
 104       else
 105         {
 106           proto = nat_proto_to_ip_proto (s->nat_proto);
 107           l_port = s->out2in.port;
 108           r_port = s->ext_host_port;
 109         }
 110       init_ed_k (&ed_kv, *l_addr, l_port, *r_addr, r_port, fib_index, proto);
 111       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &ed_kv, 0))
 112         nat_elog_warn ("out2in_ed key del failed");
 113
 114       if (snat_is_unk_proto_session (s))
 115         goto delete;
 116
 117       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 118                                            s->in2out.addr.as_u32,
 119                                            s->out2in.addr.as_u32,
 120                                            s->nat_proto,
 121                                            s->in2out.port,
 122                                            s->out2in.port,
 123                                            s->in2out.fib_index);
 124
 125       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 126                              &s->in2out.addr, s->in2out.port,
 127                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 128                              &s->out2in.addr, s->out2in.port,
 129                              &s->ext_host_addr, s->ext_host_port,
 130                              s->nat_proto, is_twice_nat_session (s));
 131
 132       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 133                    s->ext_host_port, s->nat_proto, s->out2in.fib_index,
 134                    ctx->thread_index);
 135
 136       if (is_twice_nat_session (s))
 137         {
 138           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 139             {
 140               // TODO FIXME this is obviously broken - which address should be
 141               // freed here?!
 142               a = sm->twice_nat_addresses + i;
 143               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 144                 {
 145                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 146                                                       ctx->thread_index,
 147                                                       &s->ext_host_nat_addr,
 148                                                       s->ext_host_nat_port,
 149                                                       s->nat_proto);
 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.addr, s->out2in.port,
 160                                           s->nat_proto);
 161     delete:
 162       nat_ed_session_delete (sm, s, ctx->thread_index, 1);
 163       return 1;
 164     }
 165
 166   return 0;
 167 }
 168 #endif
 169
 170 static inline u32
 171 icmp_in2out_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 172                           ip4_header_t * ip0, icmp46_header_t * icmp0,
 173                           u32 sw_if_index0, u32 rx_fib_index0,
 174                           vlib_node_runtime_t * node, u32 next0, f64 now,
 175                           u32 thread_index, snat_session_t ** p_s0)
 176 {
 177   vlib_main_t *vm = vlib_get_main ();
 178
 179   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 180                        next0, thread_index, p_s0, 0);
 181   snat_session_t *s0 = *p_s0;
 182   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
 183     {
 184       /* Accounting */
 185       nat44_session_update_counters (s0, now,
 186                                      vlib_buffer_length_in_chain
 187                                      (vm, b0), thread_index);
 188       /* Per-user LRU list maintenance */
 189       nat44_session_update_lru (sm, s0, thread_index);
 190     }
 191   return next0;
 192 }
 193
 194 static int
 195 nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
 196                             u32 nat_proto, u32 thread_index,
 197                             ip4_address_t r_addr, u16 r_port, u8 proto,
 198                             u16 port_per_thread, u32 snat_thread_index,
 199                             snat_session_t * s,
 200                             ip4_address_t * outside_addr,
 201                             u16 * outside_port,
 202                             clib_bihash_kv_16_8_t * out2in_ed_kv)
 203 {
 204   int i;
 205   snat_address_t *a, *ga = 0;
 206   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 207
 208   const u16 port_thread_offset = (port_per_thread * snat_thread_index) + 1024;
 209
 210   for (i = 0; i < vec_len (sm->addresses); i++)
 211     {
 212       a = sm->addresses + i;
 213       switch (nat_proto)
 214         {
 215 #define _(N, j, n, unused)                                                   \
 216   case NAT_PROTOCOL_##N:                                                     \
 217     if (a->fib_index == rx_fib_index)                                        \
 218       {                                                                      \
 219         /* first try port suggested by caller */                             \
 220         u16 port = clib_net_to_host_u16 (*outside_port);                   \
 221         u16 port_offset = port - port_thread_offset;                         \
 222         if (port <= port_thread_offset ||                                    \
 223             port > port_thread_offset + port_per_thread)                     \
 224           {                                                                  \
 225             /* need to pick a different port, suggested port doesn't fit in  \
 226              * this thread's port range */                                   \
 227             port_offset = snat_random_port (1, port_per_thread);             \
 228             port = port_thread_offset + port_offset;                         \
 229           }                                                                  \
 230         u16 attempts = port_per_thread;                                      \
 231         do                                                                   \
 232           {                                                                  \
 233             init_ed_kv (out2in_ed_kv, a->addr, clib_host_to_net_u16 (port),  \
 234                         r_addr, r_port, s->out2in.fib_index, proto,          \
 235                         thread_index, s - tsm->sessions);                    \
 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[port];                        \
 241                 a->busy_##n##_ports_per_thread[thread_index]++;              \
 242                 a->busy_##n##_ports++;                                       \
 243                 *outside_addr = a->addr;                                   \
 244                 *outside_port = clib_host_to_net_u16 (port);               \
 245                 return 0;                                                    \
 246               }                                                              \
 247             port_offset = (port_offset + 1) % port_per_thread;               \
 248             port = port_thread_offset + port_offset;                         \
 249             --attempts;                                                      \
 250           }                                                                  \
 251         while (attempts > 0);                                                \
 252       }                                                                      \
 253     else if (a->fib_index == ~0)                                             \
 254       {                                                                      \
 255         ga = a;                                                              \
 256       }                                                                      \
 257     break;
 258
 259           foreach_nat_protocol;
 260         default:
 261           nat_elog_info ("unknown protocol");
 262           return 1;
 263         }
 264     }
 265
 266   if (ga)
 267     {
 268       /* fake fib_index to reuse macro */
 269       rx_fib_index = ~0;
 270       a = ga;
 271       switch (nat_proto)
 272         {
 273           foreach_nat_protocol;
 274         default:
 275           nat_elog_info ("unknown protocol");
 276           return 1;
 277         }
 278     }
 279
 280 #undef _
 281
 282   /* Totally out of translations to use... */
 283   snat_ipfix_logging_addresses_exhausted (thread_index, 0);
 284   return 1;
 285 }
 286
 287 static_always_inline u32
 288 nat_outside_fib_index_lookup (snat_main_t * sm, ip4_address_t addr)
 289 {
 290   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 291   nat_outside_fib_t *outside_fib;
 292   fib_prefix_t pfx = {
 293     .fp_proto = FIB_PROTOCOL_IP4,
 294     .fp_len = 32,
 295     .fp_addr = {.ip4.as_u32 = addr.as_u32,}
 296     ,
 297   };
 298   // TODO: multiple vrfs none can resolve addr
 299   /* *INDENT-OFF* */
 300   vec_foreach (outside_fib, sm->outside_fibs)
 301     {
 302       fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 303       if (FIB_NODE_INDEX_INVALID != fei)
 304         {
 305           if (fib_entry_get_resolving_interface (fei) != ~0)
 306             {
 307               return outside_fib->fib_index;
 308             }
 309         }
 310     }
 311   /* *INDENT-ON* */
 312   return ~0;
 313 }
 314
 315 static u32
 316 slow_path_ed (snat_main_t * sm,
 317               vlib_buffer_t * b,
 318               ip4_address_t l_addr,
 319               ip4_address_t r_addr,
 320               u16 l_port,
 321               u16 r_port,
 322               u8 proto,
 323               u32 rx_fib_index,
 324               snat_session_t ** sessionp,
 325               vlib_node_runtime_t * node, u32 next, u32 thread_index, f64 now)
 326 {
 327   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 328   clib_bihash_kv_16_8_t out2in_ed_kv;
 329   nat44_is_idle_session_ctx_t ctx;
 330   ip4_address_t outside_addr;
 331   u16 outside_port;
 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,
 356                                           sm->max_translations_per_thread);
 357           nat_elog_notice ("maximum sessions exceeded");
 358           return NAT_NEXT_DROP;
 359         }
 360     }
 361
 362   ip4_address_t sm_addr;
 363   u16 sm_port;
 364   u32 sm_fib_index;
 365   /* First try to match static mapping by local address and port */
 366   if (snat_static_mapping_match
 367       (sm, l_addr, l_port, rx_fib_index, nat_proto, &sm_addr, &sm_port,
 368        &sm_fib_index, 0, 0, 0, &lb, 0, &identity_nat))
 369     {
 370       s = nat_ed_session_alloc (sm, thread_index, now, proto);
 371       ASSERT (s);
 372       s->in2out.addr = l_addr;
 373       s->in2out.port = l_port;
 374       s->nat_proto = nat_proto;
 375       s->in2out.fib_index = rx_fib_index;
 376       s->out2in.fib_index = sm->outside_fib_index;
 377
 378       switch (vec_len (sm->outside_fibs))
 379         {
 380         case 0:
 381           s->out2in.fib_index = sm->outside_fib_index;
 382           break;
 383         case 1:
 384           s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 385           break;
 386         default:
 387           s->out2in.fib_index = nat_outside_fib_index_lookup (sm, r_addr);
 388           break;
 389         }
 390
 391       /* Try to create dynamic translation */
 392       outside_port = l_port;    // suggest using local port to allocation function
 393       if (nat_ed_alloc_addr_and_port (sm, rx_fib_index, nat_proto,
 394                                       thread_index, r_addr, r_port, proto,
 395                                       sm->port_per_thread,
 396                                       tsm->snat_thread_index, s,
 397                                       &outside_addr,
 398                                       &outside_port, &out2in_ed_kv))
 399         {
 400           nat_elog_notice ("addresses exhausted");
 401           b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 402           nat_ed_session_delete (sm, s, thread_index, 1);
 403           return NAT_NEXT_DROP;
 404         }
 405       s->out2in.addr = outside_addr;
 406       s->out2in.port = outside_port;
 407     }
 408   else
 409     {
 410       if (PREDICT_FALSE (identity_nat))
 411         {
 412           *sessionp = NULL;
 413           return next;
 414         }
 415       s = nat_ed_session_alloc (sm, thread_index, now, proto);
 416       ASSERT (s);
 417       s->out2in.addr = sm_addr;
 418       s->out2in.port = sm_port;
 419       s->in2out.addr = l_addr;
 420       s->in2out.port = l_port;
 421       s->nat_proto = nat_proto;
 422       s->in2out.fib_index = rx_fib_index;
 423       s->out2in.fib_index = sm->outside_fib_index;
 424       switch (vec_len (sm->outside_fibs))
 425         {
 426         case 0:
 427           s->out2in.fib_index = sm->outside_fib_index;
 428           break;
 429         case 1:
 430           s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 431           break;
 432         default:
 433           s->out2in.fib_index = nat_outside_fib_index_lookup (sm, r_addr);
 434           break;
 435         }
 436
 437       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 438
 439       init_ed_kv (&out2in_ed_kv, sm_addr, sm_port, r_addr, r_port,
 440                   s->out2in.fib_index, proto, thread_index,
 441                   s - tsm->sessions);
 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
 454   clib_bihash_kv_16_8_t in2out_ed_kv;
 455   init_ed_kv (&in2out_ed_kv, l_addr, l_port, r_addr, r_port, rx_fib_index,
 456               proto, thread_index, s - tsm->sessions);
 457   ctx.now = now;
 458   ctx.thread_index = thread_index;
 459   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &in2out_ed_kv,
 460                                                nat44_i2o_ed_is_idle_session_cb,
 461                                                &ctx))
 462     nat_elog_notice ("in2out-ed key add failed");
 463
 464   *sessionp = s;
 465
 466   /* log NAT event */
 467   snat_ipfix_logging_nat44_ses_create (thread_index,
 468                                        s->in2out.addr.as_u32,
 469                                        s->out2in.addr.as_u32,
 470                                        s->nat_proto,
 471                                        s->in2out.port,
 472                                        s->out2in.port, s->in2out.fib_index);
 473
 474   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 475                          &s->in2out.addr, s->in2out.port,
 476                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 477                          &s->out2in.addr, s->out2in.port,
 478                          &s->ext_host_addr, s->ext_host_port, s->nat_proto,
 479                          0);
 480
 481   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 482                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 483                &s->ext_host_nat_addr, s->ext_host_nat_port,
 484                s->nat_proto, s->in2out.fib_index, s->flags, thread_index, 0);
 485
 486   return next;
 487 }
 488
 489 static_always_inline int
 490 nat44_ed_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 491                         u32 sw_if_index, ip4_header_t * ip, u32 proto,
 492                         u32 rx_fib_index, u32 thread_index)
 493 {
 494   udp_header_t *udp = ip4_next_header (ip);
 495   clib_bihash_kv_16_8_t kv, value;
 496
 497   init_ed_k (&kv, ip->dst_address, udp->dst_port, ip->src_address,
 498              udp->src_port, sm->outside_fib_index, ip->protocol);
 499
 500   /* NAT packet aimed at external address if has active sessions */
 501   if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 502     {
 503       /* or is static mappings */
 504       ip4_address_t dummy_addr;
 505       u16 dummy_port;
 506       u32 dummy_fib_index;
 507       if (!snat_static_mapping_match
 508           (sm, ip->dst_address, udp->dst_port, sm->outside_fib_index, proto,
 509            &dummy_addr, &dummy_port, &dummy_fib_index, 1, 0, 0, 0, 0, 0))
 510         return 0;
 511     }
 512   else
 513     return 0;
 514
 515   if (sm->forwarding_enabled)
 516     return 1;
 517
 518   return snat_not_translate_fast (sm, node, sw_if_index, ip, proto,
 519                                   rx_fib_index);
 520 }
 521
 522 static_always_inline int
 523 nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
 524                                       u32 thread_index, f64 now,
 525                                       vlib_main_t * vm, vlib_buffer_t * b)
 526 {
 527   clib_bihash_kv_16_8_t kv, value;
 528   snat_session_t *s = 0;
 529   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 530
 531   if (!sm->forwarding_enabled)
 532     return 0;
 533
 534   if (ip->protocol == IP_PROTOCOL_ICMP)
 535     {
 536       if (get_icmp_i2o_ed_key (b, ip, 0, ~0, ~0, 0, 0, 0, &kv))
 537         return 0;
 538     }
 539   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 540     {
 541       init_ed_k (&kv, ip->src_address, vnet_buffer (b)->ip.reass.l4_src_port,
 542                  ip->dst_address, vnet_buffer (b)->ip.reass.l4_dst_port, 0,
 543                  ip->protocol);
 544     }
 545   else
 546     {
 547       init_ed_k (&kv, ip->src_address, 0, ip->dst_address, 0, 0,
 548                  ip->protocol);
 549     }
 550
 551   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 552     {
 553       ASSERT (thread_index == ed_value_get_thread_index (&value));
 554       s =
 555         pool_elt_at_index (tsm->sessions,
 556                            ed_value_get_session_index (&value));
 557       if (is_fwd_bypass_session (s))
 558         {
 559           if (ip->protocol == IP_PROTOCOL_TCP)
 560             {
 561               if (nat44_set_tcp_session_state_i2o
 562                   (sm, now, s, b, thread_index))
 563                 return 1;
 564             }
 565           /* Accounting */
 566           nat44_session_update_counters (s, now,
 567                                          vlib_buffer_length_in_chain (vm, b),
 568                                          thread_index);
 569           /* Per-user LRU list maintenance */
 570           nat44_session_update_lru (sm, s, thread_index);
 571           return 1;
 572         }
 573       else
 574         return 0;
 575     }
 576
 577   return 0;
 578 }
 579
 580 static_always_inline int
 581 nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
 582                                        u16 src_port, u16 dst_port,
 583                                        u32 thread_index, u32 rx_sw_if_index,
 584                                        u32 tx_sw_if_index)
 585 {
 586   clib_bihash_kv_16_8_t kv, value;
 587   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 588   snat_interface_t *i;
 589   snat_session_t *s;
 590   u32 rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (rx_sw_if_index);
 591   u32 tx_fib_index = ip4_fib_table_get_index_for_sw_if_index (tx_sw_if_index);
 592
 593   /* src NAT check */
 594   init_ed_k (&kv, ip->src_address, src_port, ip->dst_address, dst_port,
 595              tx_fib_index, ip->protocol);
 596   if (!clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 597     {
 598       ASSERT (thread_index == ed_value_get_thread_index (&value));
 599       s =
 600         pool_elt_at_index (tsm->sessions,
 601                            ed_value_get_session_index (&value));
 602       if (nat44_is_ses_closed (s))
 603         {
 604           nat_free_session_data (sm, s, thread_index, 0);
 605           nat_ed_session_delete (sm, s, thread_index, 1);
 606         }
 607       else
 608         s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
 609       return 1;
 610     }
 611
 612   /* dst NAT check */
 613   init_ed_k (&kv, ip->dst_address, dst_port, ip->src_address, src_port,
 614              rx_fib_index, ip->protocol);
 615   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 616     {
 617       ASSERT (thread_index == ed_value_get_thread_index (&value));
 618       s =
 619         pool_elt_at_index (tsm->sessions,
 620                            ed_value_get_session_index (&value));
 621       if (is_fwd_bypass_session (s))
 622         return 0;
 623
 624       /* hairpinning */
 625       /* *INDENT-OFF* */
 626       pool_foreach (i, sm->output_feature_interfaces,
 627       ({
 628         if ((nat_interface_is_inside (i)) && (rx_sw_if_index == i->sw_if_index))
 629            return 0;
 630       }));
 631       /* *INDENT-ON* */
 632       return 1;
 633     }
 634
 635   return 0;
 636 }
 637
 638 #ifndef CLIB_MARCH_VARIANT
 639 u32
 640 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 641                       u32 thread_index, vlib_buffer_t * b,
 642                       ip4_header_t * ip, ip4_address_t * addr,
 643                       u16 * port, u32 * fib_index, nat_protocol_t * proto,
 644                       void *d, void *e, u8 * dont_translate)
 645 {
 646   u32 sw_if_index;
 647   u32 rx_fib_index;
 648   clib_bihash_kv_16_8_t kv, value;
 649   u32 next = ~0;
 650   int err;
 651   snat_session_t *s = NULL;
 652   u16 l_port = 0, r_port = 0;   // initialize to workaround gcc warning
 653   vlib_main_t *vm = vlib_get_main ();
 654   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 655   *dont_translate = 0;
 656
 657   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 658   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 659
 660   err =
 661     get_icmp_i2o_ed_key (b, ip, rx_fib_index, ~0, ~0, proto, &l_port,
 662                          &r_port, &kv);
 663   if (err != 0)
 664     {
 665       b->error = node->errors[err];
 666       next = NAT_NEXT_DROP;
 667       goto out;
 668     }
 669
 670   if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 671     {
 672       if (vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0)
 673         {
 674           if (PREDICT_FALSE
 675               (nat44_ed_not_translate_output_feature
 676                (sm, ip, l_port, r_port, thread_index,
 677                 sw_if_index, vnet_buffer (b)->sw_if_index[VLIB_TX])))
 678             {
 679               *dont_translate = 1;
 680               goto out;
 681             }
 682         }
 683       else
 684         {
 685           if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
 686                                                      ip, NAT_PROTOCOL_ICMP,
 687                                                      rx_fib_index,
 688                                                      thread_index)))
 689             {
 690               *dont_translate = 1;
 691               goto out;
 692             }
 693         }
 694
 695       if (PREDICT_FALSE
 696           (icmp_type_is_error_message
 697            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 698         {
 699           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 700           next = NAT_NEXT_DROP;
 701           goto out;
 702         }
 703
 704       next =
 705         slow_path_ed (sm, b, ip->src_address, ip->dst_address, l_port, r_port,
 706                       ip->protocol, rx_fib_index, &s, node, next,
 707                       thread_index, vlib_time_now (vm));
 708
 709       if (PREDICT_FALSE (next == NAT_NEXT_DROP))
 710         goto out;
 711
 712       if (!s)
 713         {
 714           *dont_translate = 1;
 715           goto out;
 716         }
 717     }
 718   else
 719     {
 720       if (PREDICT_FALSE
 721           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 722            ICMP4_echo_request
 723            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 724            ICMP4_echo_reply
 725            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 726                                            reass.icmp_type_or_tcp_flags)))
 727         {
 728           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 729           next = NAT_NEXT_DROP;
 730           goto out;
 731         }
 732
 733       ASSERT (thread_index == ed_value_get_thread_index (&value));
 734       s =
 735         pool_elt_at_index (tsm->sessions,
 736                            ed_value_get_session_index (&value));
 737     }
 738 out:
 739   if (s)
 740     {
 741       *addr = s->out2in.addr;
 742       *port = s->out2in.port;
 743       *fib_index = s->out2in.fib_index;
 744     }
 745   if (d)
 746     {
 747       *(snat_session_t **) d = s;
 748     }
 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   init_ed_k (&s_kv, ip->src_address, 0, ip->dst_address, 0, rx_fib_index,
 788              ip->protocol);
 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,
 806                                           sm->max_translations_per_thread);
 807           nat_elog_notice ("maximum sessions exceeded");
 808           return 0;
 809         }
 810
 811       init_nat_k (&kv, ip->src_address, 0, rx_fib_index, 0);
 812
 813       /* Try to find static mapping first */
 814       if (!clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 815         {
 816           m = pool_elt_at_index (sm->static_mappings, value.value);
 817           new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 818           is_sm = 1;
 819           goto create_ses;
 820         }
 821       else
 822         {
 823           /* *INDENT-OFF* */
 824           pool_foreach (s, tsm->sessions, {
 825             if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
 826               {
 827                 new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 828
 829                 init_ed_k(&s_kv, s->out2in.addr, 0, ip->dst_address, 0, outside_fib_index, ip->protocol);
 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               init_ed_k (&s_kv, sm->addresses[i].addr, 0, ip->dst_address, 0,
 841                          outside_fib_index, ip->protocol);
 842               if (clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
 843                 {
 844                   new_addr = ip->src_address.as_u32 =
 845                     sm->addresses[i].addr.as_u32;
 846                   goto create_ses;
 847                 }
 848             }
 849           return 0;
 850         }
 851
 852     create_ses:
 853       s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
 854       if (!s)
 855         {
 856           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 857           nat_elog_warn ("create NAT session failed");
 858           return 0;
 859         }
 860
 861       s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
 862       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 863       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 864       s->out2in.addr.as_u32 = new_addr;
 865       s->out2in.fib_index = outside_fib_index;
 866       s->in2out.addr.as_u32 = old_addr;
 867       s->in2out.fib_index = rx_fib_index;
 868       s->in2out.port = s->out2in.port = ip->protocol;
 869       if (is_sm)
 870         s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 871
 872       /* Add to lookup tables */
 873       init_ed_kv (&s_kv, s->in2out.addr, 0, ip->dst_address, 0, rx_fib_index,
 874                   ip->protocol, thread_index, s - tsm->sessions);
 875       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 876         nat_elog_notice ("in2out key add failed");
 877
 878       init_ed_kv (&s_kv, s->out2in.addr, 0, ip->dst_address, 0,
 879                   outside_fib_index, ip->protocol, thread_index,
 880                   s - tsm->sessions);
 881       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &s_kv, 1))
 882         nat_elog_notice ("out2in key add failed");
 883     }
 884
 885   /* Update IP checksum */
 886   sum = ip->checksum;
 887   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 888   ip->checksum = ip_csum_fold (sum);
 889
 890   /* Accounting */
 891   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 892                                  thread_index);
 893   /* Per-user LRU list maintenance */
 894   nat44_session_update_lru (sm, s, thread_index);
 895
 896   /* Hairpinning */
 897   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 898     nat44_ed_hairpinning_unknown_proto (sm, b, ip);
 899
 900   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 901     vnet_buffer (b)->sw_if_index[VLIB_TX] = outside_fib_index;
 902
 903   return s;
 904 }
 905
 906 static inline uword
 907 nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 908                                           vlib_node_runtime_t * node,
 909                                           vlib_frame_t * frame,
 910                                           int is_output_feature)
 911 {
 912   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 913   nat_next_t next_index;
 914   snat_main_t *sm = &snat_main;
 915   f64 now = vlib_time_now (vm);
 916   u32 thread_index = vm->thread_index;
 917   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 918   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 919     0, def_slow;
 920
 921   def_slow = is_output_feature ? NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH :
 922     NAT_NEXT_IN2OUT_ED_SLOW_PATH;
 923
 924   stats_node_index = sm->ed_in2out_node_index;
 925
 926   from = vlib_frame_vector_args (frame);
 927   n_left_from = frame->n_vectors;
 928   next_index = node->cached_next_index;
 929
 930   while (n_left_from > 0)
 931     {
 932       u32 n_left_to_next;
 933
 934       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 935
 936       while (n_left_from > 0 && n_left_to_next > 0)
 937         {
 938           u32 bi0;
 939           vlib_buffer_t *b0;
 940           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
 941             new_addr0, old_addr0;
 942           u16 old_port0, new_port0;
 943           ip4_header_t *ip0;
 944           udp_header_t *udp0;
 945           tcp_header_t *tcp0;
 946           snat_session_t *s0 = 0;
 947           clib_bihash_kv_16_8_t kv0, value0;
 948           ip_csum_t sum0;
 949
 950           /* speculatively enqueue b0 to the current next frame */
 951           bi0 = from[0];
 952           to_next[0] = bi0;
 953           from += 1;
 954           to_next += 1;
 955           n_left_from -= 1;
 956           n_left_to_next -= 1;
 957
 958           b0 = vlib_get_buffer (vm, bi0);
 959
 960           if (is_output_feature)
 961             {
 962               vnet_feature_next (&vnet_buffer2 (b0)->nat.arc_next, b0);
 963               iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 964             }
 965
 966           next0 = vnet_buffer2 (b0)->nat.arc_next;
 967
 968           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 969                                   iph_offset0);
 970
 971           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 972           rx_fib_index0 =
 973             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 974                                                  sw_if_index0);
 975
 976           if (PREDICT_FALSE (ip0->ttl == 1))
 977             {
 978               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 979               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 980                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 981                                            0);
 982               next0 = NAT_NEXT_ICMP_ERROR;
 983               goto trace0;
 984             }
 985
 986           udp0 = ip4_next_header (ip0);
 987           tcp0 = (tcp_header_t *) udp0;
 988           proto0 = ip_proto_to_nat_proto (ip0->protocol);
 989
 990           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 991             {
 992               next0 = def_slow;
 993               goto trace0;
 994             }
 995
 996           if (is_output_feature)
 997             {
 998               if (PREDICT_FALSE (nat_not_translate_output_feature_fwd
 999                                  (sm, ip0, thread_index, now, vm, b0)))
1000                 goto trace0;
1001             }
1002
1003           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1004             {
1005               next0 = def_slow;
1006               goto trace0;
1007             }
1008
1009           init_ed_k (&kv0, ip0->src_address,
1010                      vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address,
1011                      vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
1012                      ip0->protocol);
1013
1014           // lookup for session
1015           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1016             {
1017               // session does not exist go slow path
1018               next0 = def_slow;
1019               goto trace0;
1020             }
1021           ASSERT (thread_index == ed_value_get_thread_index (&value0));
1022           s0 =
1023             pool_elt_at_index (tsm->sessions,
1024                                ed_value_get_session_index (&value0));
1025
1026           if (s0->tcp_closed_timestamp)
1027             {
1028               if (now >= s0->tcp_closed_timestamp)
1029                 {
1030                   // session is closed, go slow path
1031                   next0 = def_slow;
1032                 }
1033               else
1034                 {
1035                   // session in transitory timeout, drop
1036                   b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TCP_CLOSED];
1037                   next0 = NAT_NEXT_DROP;
1038                 }
1039               goto trace0;
1040             }
1041
1042           // drop if session expired
1043           u64 sess_timeout_time;
1044           sess_timeout_time = s0->last_heard +
1045             (f64) nat44_session_get_timeout (sm, s0);
1046           if (now >= sess_timeout_time)
1047             {
1048               nat_free_session_data (sm, s0, thread_index, 0);
1049               nat_ed_session_delete (sm, s0, thread_index, 1);
1050               // session is closed, go slow path
1051               next0 = def_slow;
1052               goto trace0;
1053             }
1054
1055           b0->flags |= VNET_BUFFER_F_IS_NATED;
1056
1057           if (!is_output_feature)
1058             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1059
1060           old_addr0 = ip0->src_address.as_u32;
1061           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1062           sum0 = ip0->checksum;
1063           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1064                                  src_address);
1065           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1066             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1067                                    s0->ext_host_addr.as_u32, ip4_header_t,
1068                                    dst_address);
1069           ip0->checksum = ip_csum_fold (sum0);
1070
1071           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1072
1073           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1074             {
1075               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1076                 {
1077                   new_port0 = udp0->src_port = s0->out2in.port;
1078                   sum0 = tcp0->checksum;
1079                   sum0 =
1080                     ip_csum_update (sum0, old_addr0, new_addr0,
1081                                     ip4_header_t, dst_address);
1082                   sum0 =
1083                     ip_csum_update (sum0, old_port0, new_port0,
1084                                     ip4_header_t, length);
1085                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1086                     {
1087                       sum0 =
1088                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1089                                         s0->ext_host_addr.as_u32,
1090                                         ip4_header_t, dst_address);
1091                       sum0 =
1092                         ip_csum_update (sum0,
1093                                         vnet_buffer (b0)->ip.
1094                                         reass.l4_dst_port, s0->ext_host_port,
1095                                         ip4_header_t, length);
1096                       tcp0->dst_port = s0->ext_host_port;
1097                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1098                     }
1099                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1100                   tcp0->checksum = ip_csum_fold (sum0);
1101                 }
1102               tcp_packets++;
1103               if (nat44_set_tcp_session_state_i2o
1104                   (sm, now, s0, b0, thread_index))
1105                 goto trace0;
1106             }
1107           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1108                    && udp0->checksum)
1109             {
1110               new_port0 = udp0->src_port = s0->out2in.port;
1111               sum0 = udp0->checksum;
1112               sum0 =
1113                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1114                                 dst_address);
1115               sum0 =
1116                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1117                                 length);
1118               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1119                 {
1120                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1121                                          s0->ext_host_addr.as_u32,
1122                                          ip4_header_t, dst_address);
1123                   sum0 =
1124                     ip_csum_update (sum0,
1125                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1126                                     s0->ext_host_port, ip4_header_t, length);
1127                   udp0->dst_port = s0->ext_host_port;
1128                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1129                 }
1130               udp0->checksum = ip_csum_fold (sum0);
1131               udp_packets++;
1132             }
1133           else
1134             {
1135               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1136                 {
1137                   new_port0 = udp0->src_port = s0->out2in.port;
1138                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1139                     {
1140                       udp0->dst_port = s0->ext_host_port;
1141                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1142                     }
1143                   udp_packets++;
1144                 }
1145             }
1146
1147           /* Accounting */
1148           nat44_session_update_counters (s0, now,
1149                                          vlib_buffer_length_in_chain
1150                                          (vm, b0), thread_index);
1151           /* Per-user LRU list maintenance */
1152           nat44_session_update_lru (sm, s0, thread_index);
1153
1154         trace0:
1155           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1156                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1157             {
1158               nat_in2out_ed_trace_t *t =
1159                 vlib_add_trace (vm, node, b0, sizeof (*t));
1160               t->sw_if_index = sw_if_index0;
1161               t->next_index = next0;
1162               t->is_slow_path = 0;
1163
1164               if (s0)
1165                 t->session_index = s0 - tsm->sessions;
1166               else
1167                 t->session_index = ~0;
1168             }
1169
1170           pkts_processed += next0 == vnet_buffer2 (b0)->nat.arc_next;
1171           /* verify speculative enqueue, maybe switch current next frame */
1172           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1173                                            to_next, n_left_to_next,
1174                                            bi0, next0);
1175         }
1176
1177       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1178     }
1179
1180   vlib_node_increment_counter (vm, stats_node_index,
1181                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1182                                pkts_processed);
1183   vlib_node_increment_counter (vm, stats_node_index,
1184                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1185   vlib_node_increment_counter (vm, stats_node_index,
1186                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1187   vlib_node_increment_counter (vm, stats_node_index,
1188                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1189                                icmp_packets);
1190   vlib_node_increment_counter (vm, stats_node_index,
1191                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1192                                other_packets);
1193   return frame->n_vectors;
1194 }
1195
1196 static inline uword
1197 nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
1198                                           vlib_node_runtime_t * node,
1199                                           vlib_frame_t * frame,
1200                                           int is_output_feature)
1201 {
1202   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
1203   nat_next_t next_index;
1204   snat_main_t *sm = &snat_main;
1205   f64 now = vlib_time_now (vm);
1206   u32 thread_index = vm->thread_index;
1207   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
1208   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets = 0;
1209
1210   stats_node_index = sm->ed_in2out_slowpath_node_index;
1211
1212   from = vlib_frame_vector_args (frame);
1213   n_left_from = frame->n_vectors;
1214   next_index = node->cached_next_index;
1215
1216   while (n_left_from > 0)
1217     {
1218       u32 n_left_to_next;
1219
1220       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1221
1222       while (n_left_from > 0 && n_left_to_next > 0)
1223         {
1224           u32 bi0;
1225           vlib_buffer_t *b0;
1226           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
1227             new_addr0, old_addr0;
1228           u16 old_port0, new_port0;
1229           ip4_header_t *ip0;
1230           udp_header_t *udp0;
1231           tcp_header_t *tcp0;
1232           icmp46_header_t *icmp0;
1233           snat_session_t *s0 = 0;
1234           clib_bihash_kv_16_8_t kv0, value0;
1235           ip_csum_t sum0;
1236
1237           /* speculatively enqueue b0 to the current next frame */
1238           bi0 = from[0];
1239           to_next[0] = bi0;
1240           from += 1;
1241           to_next += 1;
1242           n_left_from -= 1;
1243           n_left_to_next -= 1;
1244
1245           b0 = vlib_get_buffer (vm, bi0);
1246
1247           if (is_output_feature)
1248             iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1249
1250           next0 = vnet_buffer2 (b0)->nat.arc_next;
1251
1252           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1253                                   iph_offset0);
1254
1255           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1256           rx_fib_index0 =
1257             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1258                                                  sw_if_index0);
1259
1260           if (PREDICT_FALSE (ip0->ttl == 1))
1261             {
1262               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1263               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1264                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1265                                            0);
1266               next0 = NAT_NEXT_ICMP_ERROR;
1267               goto trace0;
1268             }
1269
1270           udp0 = ip4_next_header (ip0);
1271           tcp0 = (tcp_header_t *) udp0;
1272           icmp0 = (icmp46_header_t *) udp0;
1273           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1274
1275           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1276             {
1277               s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1278                                                   rx_fib_index0,
1279                                                   thread_index, now,
1280                                                   vm, node);
1281               if (!s0)
1282                 next0 = NAT_NEXT_DROP;
1283
1284               other_packets++;
1285               goto trace0;
1286             }
1287
1288           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1289             {
1290               next0 = icmp_in2out_ed_slow_path
1291                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
1292                  node, next0, now, thread_index, &s0);
1293               icmp_packets++;
1294               goto trace0;
1295             }
1296
1297           init_ed_k (&kv0, ip0->src_address,
1298                      vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address,
1299                      vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
1300                      ip0->protocol);
1301           if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1302             {
1303               ASSERT (thread_index == ed_value_get_thread_index (&value0));
1304               s0 =
1305                 pool_elt_at_index (tsm->sessions,
1306                                    ed_value_get_session_index (&value0));
1307
1308               if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
1309                 {
1310                   nat_free_session_data (sm, s0, thread_index, 0);
1311                   nat_ed_session_delete (sm, s0, thread_index, 1);
1312                   s0 = NULL;
1313                 }
1314             }
1315
1316           if (!s0)
1317             {
1318               if (is_output_feature)
1319                 {
1320                   if (PREDICT_FALSE
1321                       (nat44_ed_not_translate_output_feature
1322                        (sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
1323                         vnet_buffer (b0)->ip.reass.l4_dst_port, thread_index,
1324                         sw_if_index0,
1325                         vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1326                     goto trace0;
1327
1328                   /*
1329                    * Send DHCP packets to the ipv4 stack, or we won't
1330                    * be able to use dhcp client on the outside interface
1331                    */
1332                   if (PREDICT_FALSE
1333                       (proto0 == NAT_PROTOCOL_UDP
1334                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1335                            clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
1336                        && ip0->dst_address.as_u32 == 0xffffffff))
1337                     goto trace0;
1338                 }
1339               else
1340                 {
1341                   if (PREDICT_FALSE
1342                       (nat44_ed_not_translate
1343                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1344                         thread_index)))
1345                     goto trace0;
1346                 }
1347
1348               next0 =
1349                 slow_path_ed (sm, b0, ip0->src_address, ip0->dst_address,
1350                               vnet_buffer (b0)->ip.reass.l4_src_port,
1351                               vnet_buffer (b0)->ip.reass.l4_dst_port,
1352                               ip0->protocol, rx_fib_index0, &s0, node, next0,
1353                               thread_index, now);
1354
1355               if (PREDICT_FALSE (next0 == NAT_NEXT_DROP))
1356                 goto trace0;
1357
1358               if (PREDICT_FALSE (!s0))
1359                 goto trace0;
1360
1361             }
1362
1363           b0->flags |= VNET_BUFFER_F_IS_NATED;
1364
1365           if (!is_output_feature)
1366             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1367
1368           old_addr0 = ip0->src_address.as_u32;
1369           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1370           sum0 = ip0->checksum;
1371           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1372                                  src_address);
1373           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1374             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1375                                    s0->ext_host_addr.as_u32, ip4_header_t,
1376                                    dst_address);
1377           ip0->checksum = ip_csum_fold (sum0);
1378
1379           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1380
1381           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1382             {
1383               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1384                 {
1385                   new_port0 = udp0->src_port = s0->out2in.port;
1386                   sum0 = tcp0->checksum;
1387                   sum0 =
1388                     ip_csum_update (sum0, old_addr0, new_addr0,
1389                                     ip4_header_t, dst_address);
1390                   sum0 =
1391                     ip_csum_update (sum0, old_port0, new_port0,
1392                                     ip4_header_t, length);
1393                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1394                     {
1395                       sum0 =
1396                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1397                                         s0->ext_host_addr.as_u32,
1398                                         ip4_header_t, dst_address);
1399                       sum0 =
1400                         ip_csum_update (sum0,
1401                                         vnet_buffer (b0)->ip.
1402                                         reass.l4_dst_port, s0->ext_host_port,
1403                                         ip4_header_t, length);
1404                       tcp0->dst_port = s0->ext_host_port;
1405                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1406                     }
1407                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1408                   tcp0->checksum = ip_csum_fold (sum0);
1409                 }
1410               tcp_packets++;
1411               if (nat44_set_tcp_session_state_i2o
1412                   (sm, now, s0, b0, thread_index))
1413                 goto trace0;
1414             }
1415           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1416                    && udp0->checksum)
1417             {
1418               new_port0 = udp0->src_port = s0->out2in.port;
1419               sum0 = udp0->checksum;
1420               sum0 =
1421                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1422                                 dst_address);
1423               sum0 =
1424                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1425                                 length);
1426               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1427                 {
1428                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1429                                          s0->ext_host_addr.as_u32,
1430                                          ip4_header_t, dst_address);
1431                   sum0 =
1432                     ip_csum_update (sum0,
1433                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1434                                     s0->ext_host_port, ip4_header_t, length);
1435                   udp0->dst_port = s0->ext_host_port;
1436                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1437                 }
1438               udp0->checksum = ip_csum_fold (sum0);
1439               udp_packets++;
1440             }
1441           else
1442             {
1443               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1444                 {
1445                   new_port0 = udp0->src_port = s0->out2in.port;
1446                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1447                     {
1448                       udp0->dst_port = s0->ext_host_port;
1449                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1450                     }
1451                   udp_packets++;
1452                 }
1453             }
1454
1455           /* Accounting */
1456           nat44_session_update_counters (s0, now,
1457                                          vlib_buffer_length_in_chain
1458                                          (vm, b0), thread_index);
1459           /* Per-user LRU list maintenance */
1460           nat44_session_update_lru (sm, s0, thread_index);
1461
1462         trace0:
1463           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1464                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1465             {
1466               nat_in2out_ed_trace_t *t =
1467                 vlib_add_trace (vm, node, b0, sizeof (*t));
1468               t->sw_if_index = sw_if_index0;
1469               t->next_index = next0;
1470               t->is_slow_path = 1;
1471
1472               if (s0)
1473                 t->session_index = s0 - tsm->sessions;
1474               else
1475                 t->session_index = ~0;
1476             }
1477
1478           pkts_processed += next0 == vnet_buffer2 (b0)->nat.arc_next;
1479
1480           /* verify speculative enqueue, maybe switch current next frame */
1481           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1482                                            to_next, n_left_to_next,
1483                                            bi0, next0);
1484         }
1485
1486       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1487     }
1488
1489   vlib_node_increment_counter (vm, stats_node_index,
1490                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1491                                pkts_processed);
1492   vlib_node_increment_counter (vm, stats_node_index,
1493                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1494   vlib_node_increment_counter (vm, stats_node_index,
1495                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1496   vlib_node_increment_counter (vm, stats_node_index,
1497                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1498                                icmp_packets);
1499   vlib_node_increment_counter (vm, stats_node_index,
1500                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1501                                other_packets);
1502   return frame->n_vectors;
1503 }
1504
1505 VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
1506                                      vlib_node_runtime_t * node,
1507                                      vlib_frame_t * frame)
1508 {
1509   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
1510 }
1511
1512 /* *INDENT-OFF* */
1513 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1514   .name = "nat44-ed-in2out",
1515   .vector_size = sizeof (u32),
1516   .sibling_of = "nat-default",
1517   .format_trace = format_nat_in2out_ed_trace,
1518   .type = VLIB_NODE_TYPE_INTERNAL,
1519   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1520   .error_strings = nat_in2out_ed_error_strings,
1521   .runtime_data_bytes = sizeof (snat_runtime_t),
1522 };
1523 /* *INDENT-ON* */
1524
1525 VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
1526                                             vlib_node_runtime_t * node,
1527                                             vlib_frame_t * frame)
1528 {
1529   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
1530 }
1531
1532 /* *INDENT-OFF* */
1533 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1534   .name = "nat44-ed-in2out-output",
1535   .vector_size = sizeof (u32),
1536   .sibling_of = "nat-default",
1537   .format_trace = format_nat_in2out_ed_trace,
1538   .type = VLIB_NODE_TYPE_INTERNAL,
1539   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1540   .error_strings = nat_in2out_ed_error_strings,
1541   .runtime_data_bytes = sizeof (snat_runtime_t),
1542 };
1543 /* *INDENT-ON* */
1544
1545 VLIB_NODE_FN (nat44_ed_in2out_slowpath_node) (vlib_main_t * vm,
1546                                               vlib_node_runtime_t *
1547                                               node, vlib_frame_t * frame)
1548 {
1549   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 0);
1550 }
1551
1552 /* *INDENT-OFF* */
1553 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1554   .name = "nat44-ed-in2out-slowpath",
1555   .vector_size = sizeof (u32),
1556   .sibling_of = "nat-default",
1557   .format_trace = format_nat_in2out_ed_trace,
1558   .type = VLIB_NODE_TYPE_INTERNAL,
1559   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1560   .error_strings = nat_in2out_ed_error_strings,
1561   .runtime_data_bytes = sizeof (snat_runtime_t),
1562 };
1563 /* *INDENT-ON* */
1564
1565 VLIB_NODE_FN (nat44_ed_in2out_output_slowpath_node) (vlib_main_t * vm,
1566                                                      vlib_node_runtime_t
1567                                                      * node,
1568                                                      vlib_frame_t * frame)
1569 {
1570   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 1);
1571 }
1572
1573 /* *INDENT-OFF* */
1574 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1575   .name = "nat44-ed-in2out-output-slowpath",
1576   .vector_size = sizeof (u32),
1577   .sibling_of = "nat-default",
1578   .format_trace = format_nat_in2out_ed_trace,
1579   .type = VLIB_NODE_TYPE_INTERNAL,
1580   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1581   .error_strings = nat_in2out_ed_error_strings,
1582   .runtime_data_bytes = sizeof (snat_runtime_t),
1583 };
1584 /* *INDENT-ON* */
1585
1586 static u8 *
1587 format_nat_pre_trace (u8 * s, va_list * args)
1588 {
1589   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1590   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1591   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1592   return format (s, "in2out next_index %d arc_next_index %d", t->next_index,
1593                  t->arc_next_index);
1594 }
1595
1596 VLIB_NODE_FN (nat_pre_in2out_node)
1597   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1598 {
1599   return nat_pre_node_fn_inline (vm, node, frame,
1600                                  NAT_NEXT_IN2OUT_ED_FAST_PATH);
1601 }
1602
1603 /* *INDENT-OFF* */
1604 VLIB_REGISTER_NODE (nat_pre_in2out_node) = {
1605   .name = "nat-pre-in2out",
1606   .vector_size = sizeof (u32),
1607   .sibling_of = "nat-default",
1608   .format_trace = format_nat_pre_trace,
1609   .type = VLIB_NODE_TYPE_INTERNAL,
1610   .n_errors = 0,
1611 };
1612 /* *INDENT-ON* */
1613
1614 /*
1615  * fd.io coding-style-patch-verification: ON
1616  *
1617  * Local Variables:
1618  * eval: (c-set-style "gnu")
1619  * End:
1620  */