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, pkts_processed = 0, stats_node_index;
 913   snat_main_t *sm = &snat_main;
 914   f64 now = vlib_time_now (vm);
 915   u32 thread_index = vm->thread_index;
 916   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 917   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 918     0, def_slow;
 919
 920   def_slow = is_output_feature ? NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH :
 921     NAT_NEXT_IN2OUT_ED_SLOW_PATH;
 922
 923   stats_node_index = sm->ed_in2out_node_index;
 924
 925   from = vlib_frame_vector_args (frame);
 926   n_left_from = frame->n_vectors;
 927
 928   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 929   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 930   vlib_get_buffers (vm, from, b, n_left_from);
 931
 932   while (n_left_from > 0)
 933     {
 934       vlib_buffer_t *b0;
 935       u32 sw_if_index0, rx_fib_index0, proto0, new_addr0, old_addr0,
 936         iph_offset0 = 0;
 937       u16 old_port0, new_port0;
 938       ip4_header_t *ip0;
 939       udp_header_t *udp0;
 940       tcp_header_t *tcp0;
 941       snat_session_t *s0 = 0;
 942       clib_bihash_kv_16_8_t kv0, value0;
 943       ip_csum_t sum0;
 944
 945       b0 = *b;
 946
 947       if (is_output_feature)
 948         {
 949           vnet_feature_next (&vnet_buffer2 (b0)->nat.arc_next, b0);
 950           iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 951         }
 952
 953       next[0] = vnet_buffer2 (b0)->nat.arc_next;
 954
 955       ip0 =
 956         (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) + iph_offset0);
 957
 958       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 959       rx_fib_index0 =
 960         fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
 961
 962       if (PREDICT_FALSE (ip0->ttl == 1))
 963         {
 964           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 965           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 966                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
 967                                        0);
 968           next[0] = NAT_NEXT_ICMP_ERROR;
 969           goto trace0;
 970         }
 971
 972       udp0 = ip4_next_header (ip0);
 973       tcp0 = (tcp_header_t *) udp0;
 974       proto0 = ip_proto_to_nat_proto (ip0->protocol);
 975
 976       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 977         {
 978           next[0] = def_slow;
 979           goto trace0;
 980         }
 981
 982       if (is_output_feature)
 983         {
 984           if (PREDICT_FALSE
 985               (nat_not_translate_output_feature_fwd
 986                (sm, ip0, thread_index, now, vm, b0)))
 987             goto trace0;
 988         }
 989
 990       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 991         {
 992           next[0] = def_slow;
 993           goto trace0;
 994         }
 995
 996       init_ed_k (&kv0, ip0->src_address,
 997                  vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address,
 998                  vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
 999                  ip0->protocol);
1000
1001       // lookup for session
1002       if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1003         {
1004           // session does not exist go slow path
1005           next[0] = def_slow;
1006           goto trace0;
1007         }
1008       ASSERT (thread_index == ed_value_get_thread_index (&value0));
1009       s0 =
1010         pool_elt_at_index (tsm->sessions,
1011                            ed_value_get_session_index (&value0));
1012
1013       if (s0->tcp_closed_timestamp)
1014         {
1015           if (now >= s0->tcp_closed_timestamp)
1016             {
1017               // session is closed, go slow path
1018               next[0] = def_slow;
1019             }
1020           else
1021             {
1022               // session in transitory timeout, drop
1023               b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TCP_CLOSED];
1024               next[0] = NAT_NEXT_DROP;
1025             }
1026           goto trace0;
1027         }
1028
1029       // drop if session expired
1030       u64 sess_timeout_time;
1031       sess_timeout_time =
1032         s0->last_heard + (f64) nat44_session_get_timeout (sm, s0);
1033       if (now >= sess_timeout_time)
1034         {
1035           nat_free_session_data (sm, s0, thread_index, 0);
1036           nat_ed_session_delete (sm, s0, thread_index, 1);
1037           // session is closed, go slow path
1038           next[0] = def_slow;
1039           goto trace0;
1040         }
1041
1042       b0->flags |= VNET_BUFFER_F_IS_NATED;
1043
1044       if (!is_output_feature)
1045         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1046
1047       old_addr0 = ip0->src_address.as_u32;
1048       new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1049       sum0 = ip0->checksum;
1050       sum0 =
1051         ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1052                         src_address);
1053       if (PREDICT_FALSE (is_twice_nat_session (s0)))
1054         sum0 =
1055           ip_csum_update (sum0, ip0->dst_address.as_u32,
1056                           s0->ext_host_addr.as_u32, ip4_header_t,
1057                           dst_address);
1058       ip0->checksum = ip_csum_fold (sum0);
1059
1060       old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1061
1062       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1063         {
1064           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1065             {
1066               new_port0 = udp0->src_port = s0->out2in.port;
1067               sum0 = tcp0->checksum;
1068               sum0 =
1069                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1070                                 dst_address);
1071               sum0 =
1072                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1073                                 length);
1074               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1075                 {
1076                   sum0 =
1077                     ip_csum_update (sum0, ip0->dst_address.as_u32,
1078                                     s0->ext_host_addr.as_u32, ip4_header_t,
1079                                     dst_address);
1080                   sum0 =
1081                     ip_csum_update (sum0,
1082                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1083                                     s0->ext_host_port, ip4_header_t, length);
1084                   tcp0->dst_port = s0->ext_host_port;
1085                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1086                 }
1087               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1088               tcp0->checksum = ip_csum_fold (sum0);
1089             }
1090           tcp_packets++;
1091           if (nat44_set_tcp_session_state_i2o (sm, now, s0, b0, thread_index))
1092             goto trace0;
1093         }
1094       else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1095                && udp0->checksum)
1096         {
1097           new_port0 = udp0->src_port = s0->out2in.port;
1098           sum0 = udp0->checksum;
1099           sum0 =
1100             ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1101                             dst_address);
1102           sum0 =
1103             ip_csum_update (sum0, old_port0, new_port0, ip4_header_t, length);
1104           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1105             {
1106               sum0 =
1107                 ip_csum_update (sum0, ip0->dst_address.as_u32,
1108                                 s0->ext_host_addr.as_u32, ip4_header_t,
1109                                 dst_address);
1110               sum0 =
1111                 ip_csum_update (sum0, vnet_buffer (b0)->ip.reass.l4_dst_port,
1112                                 s0->ext_host_port, ip4_header_t, length);
1113               udp0->dst_port = s0->ext_host_port;
1114               ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1115             }
1116           udp0->checksum = ip_csum_fold (sum0);
1117           udp_packets++;
1118         }
1119       else
1120         {
1121           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1122             {
1123               new_port0 = udp0->src_port = s0->out2in.port;
1124               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1125                 {
1126                   udp0->dst_port = s0->ext_host_port;
1127                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1128                 }
1129               udp_packets++;
1130             }
1131         }
1132
1133       /* Accounting */
1134       nat44_session_update_counters (s0, now,
1135                                      vlib_buffer_length_in_chain (vm, b0),
1136                                      thread_index);
1137       /* Per-user LRU list maintenance */
1138       nat44_session_update_lru (sm, s0, thread_index);
1139
1140     trace0:
1141       if (PREDICT_FALSE
1142           ((node->flags & VLIB_NODE_FLAG_TRACE)
1143            && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1144         {
1145           nat_in2out_ed_trace_t *t =
1146             vlib_add_trace (vm, node, b0, sizeof (*t));
1147           t->sw_if_index = sw_if_index0;
1148           t->next_index = next[0];
1149           t->is_slow_path = 0;
1150
1151           if (s0)
1152             t->session_index = s0 - tsm->sessions;
1153           else
1154             t->session_index = ~0;
1155         }
1156
1157       pkts_processed += next[0] == vnet_buffer2 (b0)->nat.arc_next;
1158
1159       n_left_from--;
1160       next++;
1161       b++;
1162     }
1163
1164   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1165                                frame->n_vectors);
1166
1167   vlib_node_increment_counter (vm, stats_node_index,
1168                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1169                                pkts_processed);
1170   vlib_node_increment_counter (vm, stats_node_index,
1171                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1172   vlib_node_increment_counter (vm, stats_node_index,
1173                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1174   vlib_node_increment_counter (vm, stats_node_index,
1175                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1176                                icmp_packets);
1177   vlib_node_increment_counter (vm, stats_node_index,
1178                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1179                                other_packets);
1180   return frame->n_vectors;
1181 }
1182
1183 static inline uword
1184 nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
1185                                           vlib_node_runtime_t * node,
1186                                           vlib_frame_t * frame,
1187                                           int is_output_feature)
1188 {
1189   u32 n_left_from, *from, pkts_processed = 0, stats_node_index;
1190   snat_main_t *sm = &snat_main;
1191   f64 now = vlib_time_now (vm);
1192   u32 thread_index = vm->thread_index;
1193   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
1194   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets = 0;
1195
1196   stats_node_index = sm->ed_in2out_slowpath_node_index;
1197
1198   from = vlib_frame_vector_args (frame);
1199   n_left_from = frame->n_vectors;
1200
1201   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
1202   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
1203   vlib_get_buffers (vm, from, b, n_left_from);
1204
1205   while (n_left_from > 0)
1206     {
1207       vlib_buffer_t *b0;
1208       u32 sw_if_index0, rx_fib_index0, proto0, new_addr0, old_addr0,
1209         iph_offset0 = 0;
1210       u16 old_port0, new_port0;
1211       ip4_header_t *ip0;
1212       udp_header_t *udp0;
1213       tcp_header_t *tcp0;
1214       icmp46_header_t *icmp0;
1215       snat_session_t *s0 = 0;
1216       clib_bihash_kv_16_8_t kv0, value0;
1217       ip_csum_t sum0;
1218
1219       b0 = *b;
1220
1221       if (is_output_feature)
1222         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1223
1224       next[0] = vnet_buffer2 (b0)->nat.arc_next;
1225
1226       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1227                               iph_offset0);
1228
1229       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1230       rx_fib_index0 =
1231         fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
1232
1233       if (PREDICT_FALSE (ip0->ttl == 1))
1234         {
1235           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1236           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1237                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1238                                        0);
1239           next[0] = NAT_NEXT_ICMP_ERROR;
1240           goto trace0;
1241         }
1242
1243       udp0 = ip4_next_header (ip0);
1244       tcp0 = (tcp_header_t *) udp0;
1245       icmp0 = (icmp46_header_t *) udp0;
1246       proto0 = ip_proto_to_nat_proto (ip0->protocol);
1247
1248       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1249         {
1250           s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1251                                               rx_fib_index0,
1252                                               thread_index, now, vm, node);
1253           if (!s0)
1254             next[0] = NAT_NEXT_DROP;
1255
1256           other_packets++;
1257           goto trace0;
1258         }
1259
1260       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1261         {
1262           next[0] = icmp_in2out_ed_slow_path
1263             (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
1264              node, next[0], now, thread_index, &s0);
1265           icmp_packets++;
1266           goto trace0;
1267         }
1268
1269       init_ed_k (&kv0, ip0->src_address,
1270                  vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address,
1271                  vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
1272                  ip0->protocol);
1273       if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1274         {
1275           ASSERT (thread_index == ed_value_get_thread_index (&value0));
1276           s0 =
1277             pool_elt_at_index (tsm->sessions,
1278                                ed_value_get_session_index (&value0));
1279
1280           if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
1281             {
1282               nat_free_session_data (sm, s0, thread_index, 0);
1283               nat_ed_session_delete (sm, s0, thread_index, 1);
1284               s0 = NULL;
1285             }
1286         }
1287
1288       if (!s0)
1289         {
1290           if (is_output_feature)
1291             {
1292               if (PREDICT_FALSE
1293                   (nat44_ed_not_translate_output_feature
1294                    (sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
1295                     vnet_buffer (b0)->ip.reass.l4_dst_port, thread_index,
1296                     sw_if_index0, vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1297                 goto trace0;
1298
1299               /*
1300                * Send DHCP packets to the ipv4 stack, or we won't
1301                * be able to use dhcp client on the outside interface
1302                */
1303               if (PREDICT_FALSE
1304                   (proto0 == NAT_PROTOCOL_UDP
1305                    && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1306                        clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
1307                    && ip0->dst_address.as_u32 == 0xffffffff))
1308                 goto trace0;
1309             }
1310           else
1311             {
1312               if (PREDICT_FALSE
1313                   (nat44_ed_not_translate
1314                    (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1315                     thread_index)))
1316                 goto trace0;
1317             }
1318
1319           next[0] =
1320             slow_path_ed (sm, b0, ip0->src_address, ip0->dst_address,
1321                           vnet_buffer (b0)->ip.reass.l4_src_port,
1322                           vnet_buffer (b0)->ip.reass.l4_dst_port,
1323                           ip0->protocol, rx_fib_index0, &s0, node, next[0],
1324                           thread_index, now);
1325
1326           if (PREDICT_FALSE (next[0] == NAT_NEXT_DROP))
1327             goto trace0;
1328
1329           if (PREDICT_FALSE (!s0))
1330             goto trace0;
1331
1332         }
1333
1334       b0->flags |= VNET_BUFFER_F_IS_NATED;
1335
1336       if (!is_output_feature)
1337         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1338
1339       old_addr0 = ip0->src_address.as_u32;
1340       new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1341       sum0 = ip0->checksum;
1342       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1343                              src_address);
1344       if (PREDICT_FALSE (is_twice_nat_session (s0)))
1345         sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1346                                s0->ext_host_addr.as_u32, ip4_header_t,
1347                                dst_address);
1348       ip0->checksum = ip_csum_fold (sum0);
1349
1350       old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1351
1352       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1353         {
1354           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1355             {
1356               new_port0 = udp0->src_port = s0->out2in.port;
1357               sum0 = tcp0->checksum;
1358               sum0 =
1359                 ip_csum_update (sum0, old_addr0, new_addr0,
1360                                 ip4_header_t, dst_address);
1361               sum0 =
1362                 ip_csum_update (sum0, old_port0, new_port0,
1363                                 ip4_header_t, length);
1364               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1365                 {
1366                   sum0 =
1367                     ip_csum_update (sum0, ip0->dst_address.as_u32,
1368                                     s0->ext_host_addr.as_u32,
1369                                     ip4_header_t, dst_address);
1370                   sum0 =
1371                     ip_csum_update (sum0,
1372                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1373                                     s0->ext_host_port, ip4_header_t, length);
1374                   tcp0->dst_port = s0->ext_host_port;
1375                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1376                 }
1377               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1378               tcp0->checksum = ip_csum_fold (sum0);
1379             }
1380           tcp_packets++;
1381           if (nat44_set_tcp_session_state_i2o (sm, now, s0, b0, thread_index))
1382             goto trace0;
1383         }
1384       else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1385                && udp0->checksum)
1386         {
1387           new_port0 = udp0->src_port = s0->out2in.port;
1388           sum0 = udp0->checksum;
1389           sum0 =
1390             ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1391                             dst_address);
1392           sum0 =
1393             ip_csum_update (sum0, old_port0, new_port0, ip4_header_t, length);
1394           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1395             {
1396               sum0 = 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.reass.l4_dst_port,
1402                                 s0->ext_host_port, ip4_header_t, length);
1403               udp0->dst_port = s0->ext_host_port;
1404               ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1405             }
1406           udp0->checksum = ip_csum_fold (sum0);
1407           udp_packets++;
1408         }
1409       else
1410         {
1411           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1412             {
1413               new_port0 = udp0->src_port = s0->out2in.port;
1414               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1415                 {
1416                   udp0->dst_port = s0->ext_host_port;
1417                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1418                 }
1419               udp_packets++;
1420             }
1421         }
1422
1423       /* Accounting */
1424       nat44_session_update_counters (s0, now,
1425                                      vlib_buffer_length_in_chain
1426                                      (vm, b0), thread_index);
1427       /* Per-user LRU list maintenance */
1428       nat44_session_update_lru (sm, s0, thread_index);
1429
1430     trace0:
1431       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1432                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1433         {
1434           nat_in2out_ed_trace_t *t =
1435             vlib_add_trace (vm, node, b0, sizeof (*t));
1436           t->sw_if_index = sw_if_index0;
1437           t->next_index = next[0];
1438           t->is_slow_path = 1;
1439
1440           if (s0)
1441             t->session_index = s0 - tsm->sessions;
1442           else
1443             t->session_index = ~0;
1444         }
1445
1446       pkts_processed += next[0] == vnet_buffer2 (b0)->nat.arc_next;
1447
1448       n_left_from--;
1449       next++;
1450       b++;
1451     }
1452
1453   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1454                                frame->n_vectors);
1455
1456   vlib_node_increment_counter (vm, stats_node_index,
1457                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1458                                pkts_processed);
1459   vlib_node_increment_counter (vm, stats_node_index,
1460                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1461   vlib_node_increment_counter (vm, stats_node_index,
1462                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1463   vlib_node_increment_counter (vm, stats_node_index,
1464                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1465                                icmp_packets);
1466   vlib_node_increment_counter (vm, stats_node_index,
1467                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1468                                other_packets);
1469   return frame->n_vectors;
1470 }
1471
1472 VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
1473                                      vlib_node_runtime_t * node,
1474                                      vlib_frame_t * frame)
1475 {
1476   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
1477 }
1478
1479 /* *INDENT-OFF* */
1480 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1481   .name = "nat44-ed-in2out",
1482   .vector_size = sizeof (u32),
1483   .sibling_of = "nat-default",
1484   .format_trace = format_nat_in2out_ed_trace,
1485   .type = VLIB_NODE_TYPE_INTERNAL,
1486   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1487   .error_strings = nat_in2out_ed_error_strings,
1488   .runtime_data_bytes = sizeof (snat_runtime_t),
1489 };
1490 /* *INDENT-ON* */
1491
1492 VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
1493                                             vlib_node_runtime_t * node,
1494                                             vlib_frame_t * frame)
1495 {
1496   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
1497 }
1498
1499 /* *INDENT-OFF* */
1500 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1501   .name = "nat44-ed-in2out-output",
1502   .vector_size = sizeof (u32),
1503   .sibling_of = "nat-default",
1504   .format_trace = format_nat_in2out_ed_trace,
1505   .type = VLIB_NODE_TYPE_INTERNAL,
1506   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1507   .error_strings = nat_in2out_ed_error_strings,
1508   .runtime_data_bytes = sizeof (snat_runtime_t),
1509 };
1510 /* *INDENT-ON* */
1511
1512 VLIB_NODE_FN (nat44_ed_in2out_slowpath_node) (vlib_main_t * vm,
1513                                               vlib_node_runtime_t *
1514                                               node, vlib_frame_t * frame)
1515 {
1516   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 0);
1517 }
1518
1519 /* *INDENT-OFF* */
1520 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1521   .name = "nat44-ed-in2out-slowpath",
1522   .vector_size = sizeof (u32),
1523   .sibling_of = "nat-default",
1524   .format_trace = format_nat_in2out_ed_trace,
1525   .type = VLIB_NODE_TYPE_INTERNAL,
1526   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1527   .error_strings = nat_in2out_ed_error_strings,
1528   .runtime_data_bytes = sizeof (snat_runtime_t),
1529 };
1530 /* *INDENT-ON* */
1531
1532 VLIB_NODE_FN (nat44_ed_in2out_output_slowpath_node) (vlib_main_t * vm,
1533                                                      vlib_node_runtime_t
1534                                                      * node,
1535                                                      vlib_frame_t * frame)
1536 {
1537   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 1);
1538 }
1539
1540 /* *INDENT-OFF* */
1541 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1542   .name = "nat44-ed-in2out-output-slowpath",
1543   .vector_size = sizeof (u32),
1544   .sibling_of = "nat-default",
1545   .format_trace = format_nat_in2out_ed_trace,
1546   .type = VLIB_NODE_TYPE_INTERNAL,
1547   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1548   .error_strings = nat_in2out_ed_error_strings,
1549   .runtime_data_bytes = sizeof (snat_runtime_t),
1550 };
1551 /* *INDENT-ON* */
1552
1553 static u8 *
1554 format_nat_pre_trace (u8 * s, va_list * args)
1555 {
1556   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1557   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1558   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1559   return format (s, "in2out next_index %d arc_next_index %d", t->next_index,
1560                  t->arc_next_index);
1561 }
1562
1563 VLIB_NODE_FN (nat_pre_in2out_node)
1564   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1565 {
1566   return nat_pre_node_fn_inline (vm, node, frame,
1567                                  NAT_NEXT_IN2OUT_ED_FAST_PATH);
1568 }
1569
1570 /* *INDENT-OFF* */
1571 VLIB_REGISTER_NODE (nat_pre_in2out_node) = {
1572   .name = "nat-pre-in2out",
1573   .vector_size = sizeof (u32),
1574   .sibling_of = "nat-default",
1575   .format_trace = format_nat_pre_trace,
1576   .type = VLIB_NODE_TYPE_INTERNAL,
1577   .n_errors = 0,
1578 };
1579 /* *INDENT-ON* */
1580
1581 /*
1582  * fd.io coding-style-patch-verification: ON
1583  *
1584  * Local Variables:
1585  * eval: (c-set-style "gnu")
1586  * End:
1587  */