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
  35 static char *nat_in2out_ed_error_strings[] = {
  36 #define _(sym,string) string,
  37   foreach_nat_in2out_ed_error
  38 #undef _
  39 };
  40
  41 typedef struct
  42 {
  43   u32 sw_if_index;
  44   u32 next_index;
  45   u32 session_index;
  46   u32 is_slow_path;
  47 } nat_in2out_ed_trace_t;
  48
  49 static u8 *
  50 format_nat_in2out_ed_trace (u8 * s, va_list * args)
  51 {
  52   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  53   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  54   nat_in2out_ed_trace_t *t = va_arg (*args, nat_in2out_ed_trace_t *);
  55   char *tag;
  56
  57   tag =
  58     t->is_slow_path ? "NAT44_IN2OUT_ED_SLOW_PATH" :
  59     "NAT44_IN2OUT_ED_FAST_PATH";
  60
  61   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  62               t->sw_if_index, t->next_index, t->session_index);
  63
  64   return s;
  65 }
  66
  67 #ifndef CLIB_MARCH_VARIANT
  68 int
  69 nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  70 {
  71   snat_main_t *sm = &snat_main;
  72   nat44_is_idle_session_ctx_t *ctx = arg;
  73   snat_session_t *s;
  74   u64 sess_timeout_time;
  75   nat_ed_ses_key_t ed_key;
  76   clib_bihash_kv_16_8_t ed_kv;
  77   int i;
  78   snat_address_t *a;
  79   snat_session_key_t key;
  80   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
  81                                                        ctx->thread_index);
  82
  83   s = pool_elt_at_index (tsm->sessions, kv->value);
  84   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
  85   if (ctx->now >= sess_timeout_time)
  86     {
  87       if (is_fwd_bypass_session (s))
  88         goto delete;
  89
  90       ed_key.l_addr = s->out2in.addr;
  91       ed_key.r_addr = s->ext_host_addr;
  92       ed_key.fib_index = s->out2in.fib_index;
  93       if (snat_is_unk_proto_session (s))
  94         {
  95           ed_key.proto = s->in2out.port;
  96           ed_key.r_port = 0;
  97           ed_key.l_port = 0;
  98         }
  99       else
 100         {
 101           ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
 102           ed_key.l_port = s->out2in.port;
 103           ed_key.r_port = s->ext_host_port;
 104         }
 105       ed_kv.key[0] = ed_key.as_u64[0];
 106       ed_kv.key[1] = ed_key.as_u64[1];
 107       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &ed_kv, 0))
 108         nat_elog_warn ("out2in_ed key del failed");
 109
 110       ed_bihash_kv_t bihash_key;
 111       clib_memset (&bihash_key, 0, sizeof (bihash_key));
 112       bihash_key.k.dst_address = s->ext_host_addr.as_u32;
 113       bihash_key.k.dst_port = s->ext_host_port;
 114       bihash_key.k.src_address = s->out2in.addr.as_u32;
 115       bihash_key.k.src_port = s->out2in.port;
 116       bihash_key.k.protocol = s->out2in.protocol;
 117       clib_bihash_add_del_16_8 (&sm->ed_ext_ports, &bihash_key.kv,
 118                                 0 /* is_add */ );
 119
 120       if (snat_is_unk_proto_session (s))
 121         goto delete;
 122
 123       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 124                                            s->in2out.addr.as_u32,
 125                                            s->out2in.addr.as_u32,
 126                                            s->in2out.protocol,
 127                                            s->in2out.port,
 128                                            s->out2in.port,
 129                                            s->in2out.fib_index);
 130
 131       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 132                              &s->in2out.addr, s->in2out.port,
 133                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 134                              &s->out2in.addr, s->out2in.port,
 135                              &s->ext_host_addr, s->ext_host_port,
 136                              s->in2out.protocol, is_twice_nat_session (s));
 137
 138       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 139                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 140                    ctx->thread_index);
 141
 142       if (is_twice_nat_session (s))
 143         {
 144           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 145             {
 146               key.protocol = s->in2out.protocol;
 147               key.port = s->ext_host_nat_port;
 148               a = sm->twice_nat_addresses + i;
 149               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 150                 {
 151                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 152                                                       ctx->thread_index,
 153                                                       &key);
 154                   break;
 155                 }
 156             }
 157         }
 158
 159       if (snat_is_session_static (s))
 160         goto delete;
 161
 162       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 163                                           &s->out2in);
 164     delete:
 165       nat44_delete_session (sm, s, ctx->thread_index);
 166       return 1;
 167     }
 168
 169   return 0;
 170 }
 171 #endif
 172
 173 static inline u32
 174 icmp_in2out_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 175                           ip4_header_t * ip0, icmp46_header_t * icmp0,
 176                           u32 sw_if_index0, u32 rx_fib_index0,
 177                           vlib_node_runtime_t * node, u32 next0, f64 now,
 178                           u32 thread_index, snat_session_t ** p_s0)
 179 {
 180   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 181                        next0, thread_index, p_s0, 0);
 182   snat_session_t *s0 = *p_s0;
 183   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
 184     {
 185       /* Accounting */
 186       nat44_session_update_counters (s0, now,
 187                                      vlib_buffer_length_in_chain
 188                                      (sm->vlib_main, b0), thread_index);
 189       /* Per-user LRU list maintenance */
 190       nat44_session_update_lru (sm, s0, thread_index);
 191     }
 192   return next0;
 193 }
 194
 195 static_always_inline u16
 196 snat_random_port (u16 min, u16 max)
 197 {
 198   snat_main_t *sm = &snat_main;
 199   return min + random_u32 (&sm->random_seed) /
 200     (random_u32_max () / (max - min + 1) + 1);
 201 }
 202
 203 static int
 204 nat_alloc_addr_and_port_ed (snat_address_t * addresses, u32 fib_index,
 205                             u32 thread_index, nat_ed_ses_key_t * key,
 206                             snat_session_key_t * key1, u16 port_per_thread,
 207                             u32 snat_thread_index)
 208 {
 209   int i;
 210   snat_address_t *a, *ga = 0;
 211   u32 portnum;
 212
 213   const u16 port_thread_offset = (port_per_thread * snat_thread_index) + 1024;
 214   ed_bihash_kv_t bihash_key;
 215   clib_memset (&bihash_key, 0, sizeof (bihash_key));
 216   bihash_key.k.dst_address = key->r_addr.as_u32;
 217   bihash_key.k.dst_port = key->r_port;
 218   bihash_key.k.protocol = key1->protocol;
 219
 220   for (i = 0; i < vec_len (addresses); i++)
 221     {
 222       a = addresses + i;
 223       switch (key1->protocol)
 224         {
 225 #define _(N, j, n, s)                                                     \
 226   case SNAT_PROTOCOL_##N:                                                 \
 227     if (a->fib_index == fib_index)                                        \
 228       {                                                                   \
 229         bihash_key.k.src_address = a->addr.as_u32;                        \
 230         u16 port = snat_random_port (1, port_per_thread);                 \
 231         u16 attempts = port_per_thread;                                   \
 232         while (attempts > 0)                                              \
 233           {                                                               \
 234             --attempts;                                                   \
 235             portnum = port_thread_offset + port;                          \
 236             bihash_key.k.src_port = clib_host_to_net_u16 (portnum);       \
 237             int rv = clib_bihash_add_del_16_8 (                           \
 238                 &snat_main.ed_ext_ports, &bihash_key.kv, 2 /* is_add */); \
 239             if (0 == rv)                                                  \
 240               {                                                           \
 241                 ++a->busy_##n##_port_refcounts[portnum];                  \
 242                 a->busy_##n##_ports_per_thread[thread_index]++;           \
 243                 a->busy_##n##_ports++;                                    \
 244                 key1->addr = a->addr;                                     \
 245                 key1->port = clib_host_to_net_u16 (portnum);              \
 246                 return 0;                                                 \
 247               }                                                           \
 248             port = (port + 1) % port_per_thread;                          \
 249           }                                                               \
 250       }                                                                   \
 251     else if (a->fib_index == ~0)                                          \
 252       {                                                                   \
 253         ga = a;                                                           \
 254       }                                                                   \
 255     break;
 256
 257           foreach_snat_protocol;
 258         default:
 259           nat_elog_info ("unknown protocol");
 260           return 1;
 261         }
 262     }
 263
 264   if (ga)
 265     {
 266       /* fake fib_index to reuse macro */
 267       fib_index = ~0;
 268       a = ga;
 269       switch (key1->protocol)
 270         {
 271           foreach_snat_protocol;
 272         default:
 273           nat_elog_info ("unknown protocol");
 274           return 1;
 275         }
 276     }
 277
 278 #undef _
 279
 280   /* Totally out of translations to use... */
 281   snat_ipfix_logging_addresses_exhausted (thread_index, 0);
 282   return 1;
 283 }
 284
 285 static u32
 286 slow_path_ed (snat_main_t * sm,
 287               vlib_buffer_t * b,
 288               u32 rx_fib_index,
 289               clib_bihash_kv_16_8_t * kv,
 290               snat_session_t ** sessionp,
 291               vlib_node_runtime_t * node, u32 next, u32 thread_index, f64 now)
 292 {
 293   snat_session_t *s = 0;
 294   snat_user_t *u;
 295   snat_session_key_t key0, key1;
 296   lb_nat_type_t lb = 0, is_sm = 0;
 297   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 298   nat_ed_ses_key_t *key = (nat_ed_ses_key_t *) kv->key;
 299   u32 proto = ip_proto_to_snat_proto (key->proto);
 300   nat_outside_fib_t *outside_fib;
 301   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 302   u8 identity_nat;
 303   fib_prefix_t pfx = {
 304     .fp_proto = FIB_PROTOCOL_IP4,
 305     .fp_len = 32,
 306     .fp_addr = {
 307                 .ip4.as_u32 = key->r_addr.as_u32,
 308                 },
 309   };
 310   nat44_is_idle_session_ctx_t ctx;
 311
 312   if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 313     {
 314       b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 315       nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 316       nat_elog_notice ("maximum sessions exceeded");
 317       return NAT_NEXT_DROP;
 318     }
 319
 320   key0.addr = key->l_addr;
 321   key0.port = key->l_port;
 322   key1.protocol = key0.protocol = proto;
 323   key0.fib_index = rx_fib_index;
 324   key1.fib_index = sm->outside_fib_index;
 325
 326   /* First try to match static mapping by local address and port */
 327   if (snat_static_mapping_match
 328       (sm, key0, &key1, 0, 0, 0, &lb, 0, &identity_nat))
 329     {
 330       /* Try to create dynamic translation */
 331       if (nat_alloc_addr_and_port_ed (sm->addresses, rx_fib_index,
 332                                       thread_index, key, &key1,
 333                                       sm->port_per_thread,
 334                                       tsm->snat_thread_index))
 335         {
 336           nat_elog_notice ("addresses exhausted");
 337           b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 338           return NAT_NEXT_DROP;
 339         }
 340     }
 341   else
 342     {
 343       if (PREDICT_FALSE (identity_nat))
 344         {
 345           *sessionp = s;
 346           return next;
 347         }
 348       is_sm = 1;
 349     }
 350
 351   if (PREDICT_TRUE (proto == SNAT_PROTOCOL_TCP))
 352     {
 353       if (PREDICT_FALSE
 354           (!tcp_flags_is_init
 355            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 356         {
 357           b->error = node->errors[NAT_IN2OUT_ED_ERROR_NON_SYN];
 358           if (!is_sm)
 359             snat_free_outside_address_and_port (sm->addresses,
 360                                                 thread_index, &key1);
 361           return NAT_NEXT_DROP;
 362         }
 363     }
 364
 365   u = nat_user_get_or_create (sm, &key->l_addr, rx_fib_index, thread_index);
 366   if (!u)
 367     {
 368       nat_elog_warn ("create NAT user failed");
 369       if (!is_sm)
 370         snat_free_outside_address_and_port (sm->addresses,
 371                                             thread_index, &key1);
 372       b->error = node->errors[NAT_IN2OUT_ED_ERROR_CANNOT_CREATE_USER];
 373       return NAT_NEXT_DROP;
 374     }
 375
 376   s = nat_ed_session_alloc (sm, u, thread_index, now);
 377   if (!s)
 378     {
 379       nat44_delete_user_with_no_session (sm, u, thread_index);
 380       nat_elog_warn ("create NAT session failed");
 381       if (!is_sm)
 382         snat_free_outside_address_and_port (sm->addresses,
 383                                             thread_index, &key1);
 384       b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 385       return NAT_NEXT_DROP;
 386     }
 387
 388   user_session_increment (sm, u, is_sm);
 389   if (is_sm)
 390     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 391   if (lb)
 392     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 393   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 394   s->ext_host_addr = key->r_addr;
 395   s->ext_host_port = key->r_port;
 396   s->in2out = key0;
 397   s->out2in = key1;
 398   s->out2in.protocol = key0.protocol;
 399
 400   switch (vec_len (sm->outside_fibs))
 401     {
 402     case 0:
 403       s->out2in.fib_index = sm->outside_fib_index;
 404       break;
 405     case 1:
 406       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 407       break;
 408     default:
 409       /* *INDENT-OFF* */
 410       vec_foreach (outside_fib, sm->outside_fibs)
 411        {
 412           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 413           if (FIB_NODE_INDEX_INVALID != fei)
 414             {
 415               if (fib_entry_get_resolving_interface (fei) != ~0)
 416                 {
 417                   s->out2in.fib_index = outside_fib->fib_index;
 418                   break;
 419                 }
 420             }
 421         }
 422       /* *INDENT-ON* */
 423       break;
 424     }
 425
 426   /* Add to lookup tables */
 427   kv->value = s - tsm->sessions;
 428   ctx.now = now;
 429   ctx.thread_index = thread_index;
 430   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, kv,
 431                                                nat44_i2o_ed_is_idle_session_cb,
 432                                                &ctx))
 433     nat_elog_notice ("in2out-ed key add failed");
 434
 435   make_ed_kv (kv, &key1.addr, &key->r_addr, key->proto, s->out2in.fib_index,
 436               key1.port, key->r_port);
 437   kv->value = s - tsm->sessions;
 438   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, kv,
 439                                                nat44_o2i_ed_is_idle_session_cb,
 440                                                &ctx))
 441     nat_elog_notice ("out2in-ed key add failed");
 442
 443   *sessionp = s;
 444
 445   /* log NAT event */
 446   snat_ipfix_logging_nat44_ses_create (thread_index,
 447                                        s->in2out.addr.as_u32,
 448                                        s->out2in.addr.as_u32,
 449                                        s->in2out.protocol,
 450                                        s->in2out.port,
 451                                        s->out2in.port, s->in2out.fib_index);
 452
 453   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 454                          &s->in2out.addr, s->in2out.port,
 455                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 456                          &s->out2in.addr, s->out2in.port,
 457                          &s->ext_host_addr, s->ext_host_port,
 458                          s->in2out.protocol, 0);
 459
 460   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 461                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 462                &s->ext_host_nat_addr, s->ext_host_nat_port,
 463                s->in2out.protocol, s->in2out.fib_index, s->flags,
 464                thread_index, 0);
 465
 466   return next;
 467 }
 468
 469 static_always_inline int
 470 nat44_ed_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 471                         u32 sw_if_index, ip4_header_t * ip, u32 proto,
 472                         u32 rx_fib_index, u32 thread_index)
 473 {
 474   udp_header_t *udp = ip4_next_header (ip);
 475   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 476   clib_bihash_kv_16_8_t kv, value;
 477   snat_session_key_t key0, key1;
 478
 479   make_ed_kv (&kv, &ip->dst_address, &ip->src_address, ip->protocol,
 480               sm->outside_fib_index, udp->dst_port, udp->src_port);
 481
 482   /* NAT packet aimed at external address if */
 483   /* has active sessions */
 484   if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 485     {
 486       key0.addr = ip->dst_address;
 487       key0.port = udp->dst_port;
 488       key0.protocol = proto;
 489       key0.fib_index = sm->outside_fib_index;
 490       /* or is static mappings */
 491       if (!snat_static_mapping_match (sm, key0, &key1, 1, 0, 0, 0, 0, 0))
 492         return 0;
 493     }
 494   else
 495     return 0;
 496
 497   if (sm->forwarding_enabled)
 498     return 1;
 499
 500   return snat_not_translate_fast (sm, node, sw_if_index, ip, proto,
 501                                   rx_fib_index);
 502 }
 503
 504 static_always_inline int
 505 nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
 506                                       u32 thread_index, f64 now,
 507                                       vlib_main_t * vm, vlib_buffer_t * b)
 508 {
 509   nat_ed_ses_key_t key;
 510   clib_bihash_kv_16_8_t kv, value;
 511   snat_session_t *s = 0;
 512   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 513
 514   if (!sm->forwarding_enabled)
 515     return 0;
 516
 517   if (ip->protocol == IP_PROTOCOL_ICMP)
 518     {
 519       key.as_u64[0] = key.as_u64[1] = 0;
 520       if (get_icmp_i2o_ed_key (b, ip, &key))
 521         return 0;
 522       key.fib_index = 0;
 523       kv.key[0] = key.as_u64[0];
 524       kv.key[1] = key.as_u64[1];
 525     }
 526   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 527     {
 528       make_ed_kv (&kv, &ip->src_address, &ip->dst_address, ip->protocol, 0,
 529                   vnet_buffer (b)->ip.reass.l4_src_port,
 530                   vnet_buffer (b)->ip.reass.l4_dst_port);
 531     }
 532   else
 533     {
 534       make_ed_kv (&kv, &ip->src_address, &ip->dst_address, ip->protocol, 0, 0,
 535                   0);
 536     }
 537
 538   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 539     {
 540       s = pool_elt_at_index (tsm->sessions, value.value);
 541       if (is_fwd_bypass_session (s))
 542         {
 543           if (ip->protocol == IP_PROTOCOL_TCP)
 544             {
 545               if (nat44_set_tcp_session_state_i2o
 546                   (sm, now, s, b, thread_index))
 547                 return 1;
 548             }
 549           /* Accounting */
 550           nat44_session_update_counters (s, now,
 551                                          vlib_buffer_length_in_chain (vm, b),
 552                                          thread_index);
 553           /* Per-user LRU list maintenance */
 554           nat44_session_update_lru (sm, s, thread_index);
 555           return 1;
 556         }
 557       else
 558         return 0;
 559     }
 560
 561   return 0;
 562 }
 563
 564 static_always_inline int
 565 nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
 566                                        u8 proto, u16 src_port, u16 dst_port,
 567                                        u32 thread_index, u32 rx_sw_if_index,
 568                                        u32 tx_sw_if_index)
 569 {
 570   clib_bihash_kv_16_8_t kv, value;
 571   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 572   snat_interface_t *i;
 573   snat_session_t *s;
 574   u32 rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (rx_sw_if_index);
 575   u32 tx_fib_index = ip4_fib_table_get_index_for_sw_if_index (tx_sw_if_index);
 576
 577   /* src NAT check */
 578   make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto, tx_fib_index,
 579               src_port, dst_port);
 580   if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 581     {
 582       s = pool_elt_at_index (tsm->sessions, value.value);
 583       if (nat44_is_ses_closed (s))
 584         {
 585           nat_free_session_data (sm, s, thread_index, 0);
 586           nat44_delete_session (sm, s, thread_index);
 587         }
 588       else
 589         s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
 590       return 1;
 591     }
 592
 593   /* dst NAT check */
 594   make_ed_kv (&kv, &ip->dst_address, &ip->src_address, proto, rx_fib_index,
 595               dst_port, src_port);
 596   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 597     {
 598       s = pool_elt_at_index (tsm->sessions, value.value);
 599       if (is_fwd_bypass_session (s))
 600         return 0;
 601
 602       /* hairpinning */
 603       /* *INDENT-OFF* */
 604       pool_foreach (i, sm->output_feature_interfaces,
 605       ({
 606         if ((nat_interface_is_inside (i)) && (rx_sw_if_index == i->sw_if_index))
 607            return 0;
 608       }));
 609       /* *INDENT-ON* */
 610       return 1;
 611     }
 612
 613   return 0;
 614 }
 615
 616 #ifndef CLIB_MARCH_VARIANT
 617 u32
 618 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 619                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 620                       u8 * p_proto, snat_session_key_t * p_value,
 621                       u8 * p_dont_translate, void *d, void *e)
 622 {
 623   u32 sw_if_index;
 624   u32 rx_fib_index;
 625   nat_ed_ses_key_t key;
 626   snat_session_t *s = 0;
 627   u8 dont_translate = 0;
 628   clib_bihash_kv_16_8_t kv, value;
 629   u32 next = ~0;
 630   int err;
 631   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 632
 633   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 634   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 635
 636   key.as_u64[0] = key.as_u64[1] = 0;
 637   err = get_icmp_i2o_ed_key (b, ip, &key);
 638   if (err != 0)
 639     {
 640       b->error = node->errors[err];
 641       next = NAT_NEXT_DROP;
 642       goto out;
 643     }
 644   key.fib_index = rx_fib_index;
 645
 646   kv.key[0] = key.as_u64[0];
 647   kv.key[1] = key.as_u64[1];
 648
 649   if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 650     {
 651       if (vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0)
 652         {
 653           if (PREDICT_FALSE
 654               (nat44_ed_not_translate_output_feature
 655                (sm, ip, key.proto, key.l_port, key.r_port, thread_index,
 656                 sw_if_index, vnet_buffer (b)->sw_if_index[VLIB_TX])))
 657             {
 658               dont_translate = 1;
 659               goto out;
 660             }
 661         }
 662       else
 663         {
 664           if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
 665                                                      ip, SNAT_PROTOCOL_ICMP,
 666                                                      rx_fib_index,
 667                                                      thread_index)))
 668             {
 669               dont_translate = 1;
 670               goto out;
 671             }
 672         }
 673
 674       if (PREDICT_FALSE
 675           (icmp_type_is_error_message
 676            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 677         {
 678           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 679           next = NAT_NEXT_DROP;
 680           goto out;
 681         }
 682
 683       next = slow_path_ed (sm, b, rx_fib_index, &kv, &s, node, next,
 684                            thread_index, vlib_time_now (sm->vlib_main));
 685
 686       if (PREDICT_FALSE (next == NAT_NEXT_DROP))
 687         goto out;
 688
 689       if (!s)
 690         {
 691           dont_translate = 1;
 692           goto out;
 693         }
 694     }
 695   else
 696     {
 697       if (PREDICT_FALSE
 698           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 699            ICMP4_echo_request
 700            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 701            ICMP4_echo_reply
 702            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 703                                            reass.icmp_type_or_tcp_flags)))
 704         {
 705           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 706           next = NAT_NEXT_DROP;
 707           goto out;
 708         }
 709
 710       s = pool_elt_at_index (tsm->sessions, value.value);
 711     }
 712
 713   *p_proto = ip_proto_to_snat_proto (key.proto);
 714 out:
 715   if (s)
 716     *p_value = s->out2in;
 717   *p_dont_translate = dont_translate;
 718   if (d)
 719     *(snat_session_t **) d = s;
 720   return next;
 721 }
 722 #endif
 723
 724 static snat_session_t *
 725 nat44_ed_in2out_unknown_proto (snat_main_t * sm,
 726                                vlib_buffer_t * b,
 727                                ip4_header_t * ip,
 728                                u32 rx_fib_index,
 729                                u32 thread_index,
 730                                f64 now,
 731                                vlib_main_t * vm, vlib_node_runtime_t * node)
 732 {
 733   clib_bihash_kv_8_8_t kv, value;
 734   clib_bihash_kv_16_8_t s_kv, s_value;
 735   snat_static_mapping_t *m;
 736   u32 old_addr, new_addr = 0;
 737   ip_csum_t sum;
 738   snat_user_t *u;
 739   dlist_elt_t *head, *elt;
 740   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 741   u32 elt_index, head_index, ses_index;
 742   snat_session_t *s;
 743   u32 outside_fib_index = sm->outside_fib_index;
 744   int i;
 745   u8 is_sm = 0;
 746   nat_outside_fib_t *outside_fib;
 747   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 748   fib_prefix_t pfx = {
 749     .fp_proto = FIB_PROTOCOL_IP4,
 750     .fp_len = 32,
 751     .fp_addr = {
 752                 .ip4.as_u32 = ip->dst_address.as_u32,
 753                 },
 754   };
 755
 756   switch (vec_len (sm->outside_fibs))
 757     {
 758     case 0:
 759       outside_fib_index = sm->outside_fib_index;
 760       break;
 761     case 1:
 762       outside_fib_index = sm->outside_fibs[0].fib_index;
 763       break;
 764     default:
 765       /* *INDENT-OFF* */
 766       vec_foreach (outside_fib, sm->outside_fibs)
 767         {
 768           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 769           if (FIB_NODE_INDEX_INVALID != fei)
 770             {
 771               if (fib_entry_get_resolving_interface (fei) != ~0)
 772                 {
 773                   outside_fib_index = outside_fib->fib_index;
 774                   break;
 775                 }
 776             }
 777         }
 778       /* *INDENT-ON* */
 779       break;
 780     }
 781   old_addr = ip->src_address.as_u32;
 782
 783   make_ed_kv (&s_kv, &ip->src_address, &ip->dst_address, ip->protocol,
 784               rx_fib_index, 0, 0);
 785
 786   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &s_kv, &s_value))
 787     {
 788       s = pool_elt_at_index (tsm->sessions, s_value.value);
 789       new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 790     }
 791   else
 792     {
 793       if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 794         {
 795           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 796           nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
 797           nat_elog_notice ("maximum sessions exceeded");
 798           return 0;
 799         }
 800
 801       u = nat_user_get_or_create (sm, &ip->src_address, rx_fib_index,
 802                                   thread_index);
 803       if (!u)
 804         {
 805           b->error = node->errors[NAT_IN2OUT_ED_ERROR_CANNOT_CREATE_USER];
 806           nat_elog_warn ("create NAT user failed");
 807           return 0;
 808         }
 809
 810       make_sm_kv (&kv, &ip->src_address, 0, rx_fib_index, 0);
 811
 812       /* Try to find static mapping first */
 813       if (!clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 814         {
 815           m = pool_elt_at_index (sm->static_mappings, value.value);
 816           new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 817           is_sm = 1;
 818           goto create_ses;
 819         }
 820       /* Fallback to 3-tuple key */
 821       else
 822         {
 823           /* Choose same out address as for TCP/UDP session to same destination */
 824           head_index = u->sessions_per_user_list_head_index;
 825           head = pool_elt_at_index (tsm->list_pool, head_index);
 826           elt_index = head->next;
 827           if (PREDICT_FALSE (elt_index == ~0))
 828             ses_index = ~0;
 829           else
 830             {
 831               elt = pool_elt_at_index (tsm->list_pool, elt_index);
 832               ses_index = elt->value;
 833             }
 834
 835           while (ses_index != ~0)
 836             {
 837               s = pool_elt_at_index (tsm->sessions, ses_index);
 838               elt_index = elt->next;
 839               elt = pool_elt_at_index (tsm->list_pool, elt_index);
 840               ses_index = elt->value;
 841
 842               if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
 843                 {
 844                   new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 845
 846                   make_ed_kv (&s_kv, &s->out2in.addr, &ip->dst_address,
 847                               ip->protocol, outside_fib_index, 0, 0);
 848                   if (clib_bihash_search_16_8
 849                       (&tsm->out2in_ed, &s_kv, &s_value))
 850                     goto create_ses;
 851
 852                   break;
 853                 }
 854             }
 855
 856           for (i = 0; i < vec_len (sm->addresses); i++)
 857             {
 858               make_ed_kv (&s_kv, &sm->addresses[i].addr, &ip->dst_address,
 859                           ip->protocol, outside_fib_index, 0, 0);
 860               if (clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
 861                 {
 862                   new_addr = ip->src_address.as_u32 =
 863                     sm->addresses[i].addr.as_u32;
 864                   goto create_ses;
 865                 }
 866             }
 867           return 0;
 868         }
 869
 870     create_ses:
 871       s = nat_ed_session_alloc (sm, u, thread_index, now);
 872       if (!s)
 873         {
 874           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 875           nat44_delete_user_with_no_session (sm, u, thread_index);
 876           nat_elog_warn ("create NAT session failed");
 877           return 0;
 878         }
 879
 880       s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
 881       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 882       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 883       s->out2in.addr.as_u32 = new_addr;
 884       s->out2in.fib_index = outside_fib_index;
 885       s->in2out.addr.as_u32 = old_addr;
 886       s->in2out.fib_index = rx_fib_index;
 887       s->in2out.port = s->out2in.port = ip->protocol;
 888       if (is_sm)
 889         s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 890       user_session_increment (sm, u, is_sm);
 891
 892       /* Add to lookup tables */
 893       make_ed_kv (&s_kv, &s->in2out.addr, &ip->dst_address, ip->protocol,
 894                   rx_fib_index, 0, 0);
 895       s_kv.value = s - tsm->sessions;
 896       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 897         nat_elog_notice ("in2out key add failed");
 898
 899       make_ed_kv (&s_kv, &s->out2in.addr, &ip->dst_address, ip->protocol,
 900                   outside_fib_index, 0, 0);
 901       s_kv.value = s - tsm->sessions;
 902       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
 903         nat_elog_notice ("out2in key add failed");
 904     }
 905
 906   /* Update IP checksum */
 907   sum = ip->checksum;
 908   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 909   ip->checksum = ip_csum_fold (sum);
 910
 911   /* Accounting */
 912   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 913                                  thread_index);
 914   /* Per-user LRU list maintenance */
 915   nat44_session_update_lru (sm, s, thread_index);
 916
 917   /* Hairpinning */
 918   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 919     nat44_ed_hairpinning_unknown_proto (sm, b, ip);
 920
 921   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 922     vnet_buffer (b)->sw_if_index[VLIB_TX] = outside_fib_index;
 923
 924   return s;
 925 }
 926
 927 static inline uword
 928 nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 929                                           vlib_node_runtime_t * node,
 930                                           vlib_frame_t * frame,
 931                                           int is_output_feature)
 932 {
 933   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 934   nat_next_t next_index;
 935   snat_main_t *sm = &snat_main;
 936   f64 now = vlib_time_now (vm);
 937   u32 thread_index = vm->thread_index;
 938   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 939   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 940     0, def_slow;
 941
 942   def_slow = is_output_feature ? NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH :
 943     NAT_NEXT_IN2OUT_ED_SLOW_PATH;
 944
 945   stats_node_index = sm->ed_in2out_node_index;
 946
 947   from = vlib_frame_vector_args (frame);
 948   n_left_from = frame->n_vectors;
 949   next_index = node->cached_next_index;
 950
 951   while (n_left_from > 0)
 952     {
 953       u32 n_left_to_next;
 954
 955       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 956
 957       while (n_left_from > 0 && n_left_to_next > 0)
 958         {
 959           u32 bi0;
 960           vlib_buffer_t *b0;
 961           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
 962             new_addr0, old_addr0;
 963           u16 old_port0, new_port0;
 964           ip4_header_t *ip0;
 965           udp_header_t *udp0;
 966           tcp_header_t *tcp0;
 967           snat_session_t *s0 = 0;
 968           clib_bihash_kv_16_8_t kv0, value0;
 969           ip_csum_t sum0;
 970
 971           /* speculatively enqueue b0 to the current next frame */
 972           bi0 = from[0];
 973           to_next[0] = bi0;
 974           from += 1;
 975           to_next += 1;
 976           n_left_from -= 1;
 977           n_left_to_next -= 1;
 978
 979           b0 = vlib_get_buffer (vm, bi0);
 980
 981           if (is_output_feature)
 982             {
 983               vnet_feature_next (&nat_buffer_opaque (b0)->arc_next, b0);
 984               iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 985             }
 986
 987           next0 = nat_buffer_opaque (b0)->arc_next;
 988
 989           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 990                                   iph_offset0);
 991
 992           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 993           rx_fib_index0 =
 994             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 995                                                  sw_if_index0);
 996
 997           if (PREDICT_FALSE (ip0->ttl == 1))
 998             {
 999               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1000               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1001                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1002                                            0);
1003               next0 = NAT_NEXT_ICMP_ERROR;
1004               goto trace0;
1005             }
1006
1007           udp0 = ip4_next_header (ip0);
1008           tcp0 = (tcp_header_t *) udp0;
1009           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1010
1011           if (PREDICT_FALSE (proto0 == ~0))
1012             {
1013               next0 = def_slow;
1014               goto trace0;
1015             }
1016
1017           if (is_output_feature)
1018             {
1019               if (PREDICT_FALSE (nat_not_translate_output_feature_fwd
1020                                  (sm, ip0, thread_index, now, vm, b0)))
1021                 goto trace0;
1022             }
1023
1024           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1025             {
1026               next0 = def_slow;
1027               goto trace0;
1028             }
1029
1030           make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
1031                       ip0->protocol, rx_fib_index0,
1032                       vnet_buffer (b0)->ip.reass.l4_src_port,
1033                       vnet_buffer (b0)->ip.reass.l4_dst_port);
1034
1035           // lookup for session
1036           if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1037             {
1038               // session does not exist go slow path
1039               next0 = def_slow;
1040               goto trace0;
1041             }
1042           s0 = pool_elt_at_index (tsm->sessions, value0.value);
1043
1044           if (s0->tcp_close_timestamp)
1045             {
1046               if (now >= s0->tcp_close_timestamp)
1047                 {
1048                   // session is closed, go slow path
1049                   next0 = def_slow;
1050                 }
1051               else
1052                 {
1053                   // session in transitory timeout, drop
1054                   b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TCP_CLOSED];
1055                   next0 = NAT_NEXT_DROP;
1056                 }
1057               goto trace0;
1058             }
1059
1060           // drop if session expired
1061           u64 sess_timeout_time;
1062           sess_timeout_time = s0->last_heard +
1063             (f64) nat44_session_get_timeout (sm, s0);
1064           if (now >= sess_timeout_time)
1065             {
1066               nat_free_session_data (sm, s0, thread_index, 0);
1067               nat44_delete_session (sm, s0, thread_index);
1068               // session is closed, go slow path
1069               next0 = def_slow;
1070               goto trace0;
1071             }
1072
1073           b0->flags |= VNET_BUFFER_F_IS_NATED;
1074
1075           if (!is_output_feature)
1076             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1077
1078           old_addr0 = ip0->src_address.as_u32;
1079           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1080           sum0 = ip0->checksum;
1081           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1082                                  src_address);
1083           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1084             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1085                                    s0->ext_host_addr.as_u32, ip4_header_t,
1086                                    dst_address);
1087           ip0->checksum = ip_csum_fold (sum0);
1088
1089           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1090
1091           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1092             {
1093               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1094                 {
1095                   new_port0 = udp0->src_port = s0->out2in.port;
1096                   sum0 = tcp0->checksum;
1097                   sum0 =
1098                     ip_csum_update (sum0, old_addr0, new_addr0,
1099                                     ip4_header_t, dst_address);
1100                   sum0 =
1101                     ip_csum_update (sum0, old_port0, new_port0,
1102                                     ip4_header_t, length);
1103                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1104                     {
1105                       sum0 =
1106                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1107                                         s0->ext_host_addr.as_u32,
1108                                         ip4_header_t, dst_address);
1109                       sum0 =
1110                         ip_csum_update (sum0,
1111                                         vnet_buffer (b0)->ip.
1112                                         reass.l4_dst_port, s0->ext_host_port,
1113                                         ip4_header_t, length);
1114                       tcp0->dst_port = s0->ext_host_port;
1115                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1116                     }
1117                   mss_clamping (sm, tcp0, &sum0);
1118                   tcp0->checksum = ip_csum_fold (sum0);
1119                 }
1120               tcp_packets++;
1121               if (nat44_set_tcp_session_state_i2o
1122                   (sm, now, s0, b0, thread_index))
1123                 goto trace0;
1124             }
1125           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1126                    && udp0->checksum)
1127             {
1128               new_port0 = udp0->src_port = s0->out2in.port;
1129               sum0 = udp0->checksum;
1130               sum0 =
1131                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1132                                 dst_address);
1133               sum0 =
1134                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1135                                 length);
1136               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1137                 {
1138                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1139                                          s0->ext_host_addr.as_u32,
1140                                          ip4_header_t, dst_address);
1141                   sum0 =
1142                     ip_csum_update (sum0,
1143                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1144                                     s0->ext_host_port, ip4_header_t, length);
1145                   udp0->dst_port = s0->ext_host_port;
1146                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1147                 }
1148               udp0->checksum = ip_csum_fold (sum0);
1149               udp_packets++;
1150             }
1151           else
1152             {
1153               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1154                 {
1155                   new_port0 = udp0->src_port = s0->out2in.port;
1156                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1157                     {
1158                       udp0->dst_port = s0->ext_host_port;
1159                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1160                     }
1161                   udp_packets++;
1162                 }
1163             }
1164
1165           /* Accounting */
1166           nat44_session_update_counters (s0, now,
1167                                          vlib_buffer_length_in_chain
1168                                          (vm, b0), thread_index);
1169           /* Per-user LRU list maintenance */
1170           nat44_session_update_lru (sm, s0, thread_index);
1171
1172         trace0:
1173           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1174                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1175             {
1176               nat_in2out_ed_trace_t *t =
1177                 vlib_add_trace (vm, node, b0, sizeof (*t));
1178               t->sw_if_index = sw_if_index0;
1179               t->next_index = next0;
1180               t->is_slow_path = 0;
1181
1182               if (s0)
1183                 t->session_index = s0 - tsm->sessions;
1184               else
1185                 t->session_index = ~0;
1186             }
1187
1188           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
1189           /* verify speculative enqueue, maybe switch current next frame */
1190           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1191                                            to_next, n_left_to_next,
1192                                            bi0, next0);
1193         }
1194
1195       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1196     }
1197
1198   vlib_node_increment_counter (vm, stats_node_index,
1199                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1200                                pkts_processed);
1201   vlib_node_increment_counter (vm, stats_node_index,
1202                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1203   vlib_node_increment_counter (vm, stats_node_index,
1204                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1205   vlib_node_increment_counter (vm, stats_node_index,
1206                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1207                                icmp_packets);
1208   vlib_node_increment_counter (vm, stats_node_index,
1209                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1210                                other_packets);
1211   return frame->n_vectors;
1212 }
1213
1214 static inline uword
1215 nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
1216                                           vlib_node_runtime_t * node,
1217                                           vlib_frame_t * frame,
1218                                           int is_output_feature)
1219 {
1220   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
1221   nat_next_t next_index;
1222   snat_main_t *sm = &snat_main;
1223   f64 now = vlib_time_now (vm);
1224   u32 thread_index = vm->thread_index;
1225   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
1226   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets = 0;
1227
1228   stats_node_index = sm->ed_in2out_slowpath_node_index;
1229
1230   from = vlib_frame_vector_args (frame);
1231   n_left_from = frame->n_vectors;
1232   next_index = node->cached_next_index;
1233
1234   while (n_left_from > 0)
1235     {
1236       u32 n_left_to_next;
1237
1238       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1239
1240       while (n_left_from > 0 && n_left_to_next > 0)
1241         {
1242           u32 bi0;
1243           vlib_buffer_t *b0;
1244           u32 next0, sw_if_index0, rx_fib_index0, iph_offset0 = 0, proto0,
1245             new_addr0, old_addr0;
1246           u16 old_port0, new_port0;
1247           ip4_header_t *ip0;
1248           udp_header_t *udp0;
1249           tcp_header_t *tcp0;
1250           icmp46_header_t *icmp0;
1251           snat_session_t *s0 = 0;
1252           clib_bihash_kv_16_8_t kv0, value0;
1253           ip_csum_t sum0;
1254
1255           /* speculatively enqueue b0 to the current next frame */
1256           bi0 = from[0];
1257           to_next[0] = bi0;
1258           from += 1;
1259           to_next += 1;
1260           n_left_from -= 1;
1261           n_left_to_next -= 1;
1262
1263           b0 = vlib_get_buffer (vm, bi0);
1264
1265           if (is_output_feature)
1266             iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1267
1268           next0 = nat_buffer_opaque (b0)->arc_next;
1269
1270           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1271                                   iph_offset0);
1272
1273           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1274           rx_fib_index0 =
1275             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1276                                                  sw_if_index0);
1277
1278           if (PREDICT_FALSE (ip0->ttl == 1))
1279             {
1280               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1281               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1282                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1283                                            0);
1284               next0 = NAT_NEXT_ICMP_ERROR;
1285               goto trace0;
1286             }
1287
1288           udp0 = ip4_next_header (ip0);
1289           tcp0 = (tcp_header_t *) udp0;
1290           icmp0 = (icmp46_header_t *) udp0;
1291           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1292
1293           if (PREDICT_FALSE (proto0 == ~0))
1294             {
1295               s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1296                                                   rx_fib_index0,
1297                                                   thread_index, now,
1298                                                   vm, node);
1299               if (!s0)
1300                 next0 = NAT_NEXT_DROP;
1301
1302               other_packets++;
1303               goto trace0;
1304             }
1305
1306           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1307             {
1308               next0 = icmp_in2out_ed_slow_path
1309                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
1310                  node, next0, now, thread_index, &s0);
1311               icmp_packets++;
1312               goto trace0;
1313             }
1314
1315           // move down
1316           make_ed_kv (&kv0, &ip0->src_address, &ip0->dst_address,
1317                       ip0->protocol, rx_fib_index0,
1318                       vnet_buffer (b0)->ip.reass.l4_src_port,
1319                       vnet_buffer (b0)->ip.reass.l4_dst_port);
1320
1321           if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1322             {
1323               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1324
1325               if (s0->tcp_close_timestamp && now >= s0->tcp_close_timestamp)
1326                 {
1327                   nat_free_session_data (sm, s0, thread_index, 0);
1328                   nat44_delete_session (sm, s0, thread_index);
1329                   s0 = NULL;
1330                 }
1331             }
1332
1333           if (!s0)
1334             {
1335               if (is_output_feature)
1336                 {
1337                   if (PREDICT_FALSE
1338                       (nat44_ed_not_translate_output_feature
1339                        (sm, ip0, ip0->protocol,
1340                         vnet_buffer (b0)->ip.reass.l4_src_port,
1341                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1342                         thread_index, sw_if_index0,
1343                         vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1344                     goto trace0;
1345
1346                   /*
1347                    * Send DHCP packets to the ipv4 stack, or we won't
1348                    * be able to use dhcp client on the outside interface
1349                    */
1350                   if (PREDICT_FALSE
1351                       (proto0 == SNAT_PROTOCOL_UDP
1352                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1353                            clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
1354                        && ip0->dst_address.as_u32 == 0xffffffff))
1355                     goto trace0;
1356                 }
1357               else
1358                 {
1359                   if (PREDICT_FALSE
1360                       (nat44_ed_not_translate
1361                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1362                         thread_index)))
1363                     goto trace0;
1364                 }
1365
1366               next0 = slow_path_ed (sm, b0, rx_fib_index0, &kv0, &s0, node,
1367                                     next0, thread_index, now);
1368
1369               if (PREDICT_FALSE (next0 == NAT_NEXT_DROP))
1370                 goto trace0;
1371
1372               if (PREDICT_FALSE (!s0))
1373                 goto trace0;
1374
1375             }
1376
1377           b0->flags |= VNET_BUFFER_F_IS_NATED;
1378
1379           if (!is_output_feature)
1380             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1381
1382           old_addr0 = ip0->src_address.as_u32;
1383           new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1384           sum0 = ip0->checksum;
1385           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1386                                  src_address);
1387           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1388             sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1389                                    s0->ext_host_addr.as_u32, ip4_header_t,
1390                                    dst_address);
1391           ip0->checksum = ip_csum_fold (sum0);
1392
1393           old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1394
1395           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1396             {
1397               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1398                 {
1399                   new_port0 = udp0->src_port = s0->out2in.port;
1400                   sum0 = tcp0->checksum;
1401                   sum0 =
1402                     ip_csum_update (sum0, old_addr0, new_addr0,
1403                                     ip4_header_t, dst_address);
1404                   sum0 =
1405                     ip_csum_update (sum0, old_port0, new_port0,
1406                                     ip4_header_t, length);
1407                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1408                     {
1409                       sum0 =
1410                         ip_csum_update (sum0, ip0->dst_address.as_u32,
1411                                         s0->ext_host_addr.as_u32,
1412                                         ip4_header_t, dst_address);
1413                       sum0 =
1414                         ip_csum_update (sum0,
1415                                         vnet_buffer (b0)->ip.
1416                                         reass.l4_dst_port, s0->ext_host_port,
1417                                         ip4_header_t, length);
1418                       tcp0->dst_port = s0->ext_host_port;
1419                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1420                     }
1421                   mss_clamping (sm, tcp0, &sum0);
1422                   tcp0->checksum = ip_csum_fold (sum0);
1423                 }
1424               tcp_packets++;
1425               if (nat44_set_tcp_session_state_i2o
1426                   (sm, now, s0, b0, thread_index))
1427                 goto trace0;
1428             }
1429           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1430                    && udp0->checksum)
1431             {
1432               new_port0 = udp0->src_port = s0->out2in.port;
1433               sum0 = udp0->checksum;
1434               sum0 =
1435                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1436                                 dst_address);
1437               sum0 =
1438                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1439                                 length);
1440               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1441                 {
1442                   sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1443                                          s0->ext_host_addr.as_u32,
1444                                          ip4_header_t, dst_address);
1445                   sum0 =
1446                     ip_csum_update (sum0,
1447                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1448                                     s0->ext_host_port, ip4_header_t, length);
1449                   udp0->dst_port = s0->ext_host_port;
1450                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1451                 }
1452               udp0->checksum = ip_csum_fold (sum0);
1453               udp_packets++;
1454             }
1455           else
1456             {
1457               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1458                 {
1459                   new_port0 = udp0->src_port = s0->out2in.port;
1460                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1461                     {
1462                       udp0->dst_port = s0->ext_host_port;
1463                       ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1464                     }
1465                   udp_packets++;
1466                 }
1467             }
1468
1469           /* Accounting */
1470           nat44_session_update_counters (s0, now,
1471                                          vlib_buffer_length_in_chain
1472                                          (vm, b0), thread_index);
1473           /* Per-user LRU list maintenance */
1474           nat44_session_update_lru (sm, s0, thread_index);
1475
1476         trace0:
1477           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1478                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1479             {
1480               nat_in2out_ed_trace_t *t =
1481                 vlib_add_trace (vm, node, b0, sizeof (*t));
1482               t->sw_if_index = sw_if_index0;
1483               t->next_index = next0;
1484               t->is_slow_path = 1;
1485
1486               if (s0)
1487                 t->session_index = s0 - tsm->sessions;
1488               else
1489                 t->session_index = ~0;
1490             }
1491
1492           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
1493
1494           /* verify speculative enqueue, maybe switch current next frame */
1495           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1496                                            to_next, n_left_to_next,
1497                                            bi0, next0);
1498         }
1499
1500       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1501     }
1502
1503   vlib_node_increment_counter (vm, stats_node_index,
1504                                NAT_IN2OUT_ED_ERROR_IN2OUT_PACKETS,
1505                                pkts_processed);
1506   vlib_node_increment_counter (vm, stats_node_index,
1507                                NAT_IN2OUT_ED_ERROR_TCP_PACKETS, tcp_packets);
1508   vlib_node_increment_counter (vm, stats_node_index,
1509                                NAT_IN2OUT_ED_ERROR_UDP_PACKETS, udp_packets);
1510   vlib_node_increment_counter (vm, stats_node_index,
1511                                NAT_IN2OUT_ED_ERROR_ICMP_PACKETS,
1512                                icmp_packets);
1513   vlib_node_increment_counter (vm, stats_node_index,
1514                                NAT_IN2OUT_ED_ERROR_OTHER_PACKETS,
1515                                other_packets);
1516   return frame->n_vectors;
1517 }
1518
1519 VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
1520                                      vlib_node_runtime_t * node,
1521                                      vlib_frame_t * frame)
1522 {
1523   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
1524 }
1525
1526 /* *INDENT-OFF* */
1527 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1528   .name = "nat44-ed-in2out",
1529   .vector_size = sizeof (u32),
1530   .sibling_of = "nat-default",
1531   .format_trace = format_nat_in2out_ed_trace,
1532   .type = VLIB_NODE_TYPE_INTERNAL,
1533   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1534   .error_strings = nat_in2out_ed_error_strings,
1535   .runtime_data_bytes = sizeof (snat_runtime_t),
1536 };
1537 /* *INDENT-ON* */
1538
1539 VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
1540                                             vlib_node_runtime_t * node,
1541                                             vlib_frame_t * frame)
1542 {
1543   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
1544 }
1545
1546 /* *INDENT-OFF* */
1547 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1548   .name = "nat44-ed-in2out-output",
1549   .vector_size = sizeof (u32),
1550   .sibling_of = "nat-default",
1551   .format_trace = format_nat_in2out_ed_trace,
1552   .type = VLIB_NODE_TYPE_INTERNAL,
1553   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1554   .error_strings = nat_in2out_ed_error_strings,
1555   .runtime_data_bytes = sizeof (snat_runtime_t),
1556 };
1557 /* *INDENT-ON* */
1558
1559 VLIB_NODE_FN (nat44_ed_in2out_slowpath_node) (vlib_main_t * vm,
1560                                               vlib_node_runtime_t *
1561                                               node, vlib_frame_t * frame)
1562 {
1563   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 0);
1564 }
1565
1566 /* *INDENT-OFF* */
1567 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1568   .name = "nat44-ed-in2out-slowpath",
1569   .vector_size = sizeof (u32),
1570   .sibling_of = "nat-default",
1571   .format_trace = format_nat_in2out_ed_trace,
1572   .type = VLIB_NODE_TYPE_INTERNAL,
1573   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1574   .error_strings = nat_in2out_ed_error_strings,
1575   .runtime_data_bytes = sizeof (snat_runtime_t),
1576 };
1577 /* *INDENT-ON* */
1578
1579 VLIB_NODE_FN (nat44_ed_in2out_output_slowpath_node) (vlib_main_t * vm,
1580                                                      vlib_node_runtime_t
1581                                                      * node,
1582                                                      vlib_frame_t * frame)
1583 {
1584   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 1);
1585 }
1586
1587 /* *INDENT-OFF* */
1588 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1589   .name = "nat44-ed-in2out-output-slowpath",
1590   .vector_size = sizeof (u32),
1591   .sibling_of = "nat-default",
1592   .format_trace = format_nat_in2out_ed_trace,
1593   .type = VLIB_NODE_TYPE_INTERNAL,
1594   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1595   .error_strings = nat_in2out_ed_error_strings,
1596   .runtime_data_bytes = sizeof (snat_runtime_t),
1597 };
1598 /* *INDENT-ON* */
1599
1600 static u8 *
1601 format_nat_pre_trace (u8 * s, va_list * args)
1602 {
1603   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1604   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1605   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1606   return format (s, "in2out next_index %d", t->next_index);
1607 }
1608
1609 VLIB_NODE_FN (nat_pre_in2out_node)
1610   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1611 {
1612   return nat_pre_node_fn_inline (vm, node, frame,
1613                                  NAT_NEXT_IN2OUT_ED_FAST_PATH);
1614 }
1615
1616 /* *INDENT-OFF* */
1617 VLIB_REGISTER_NODE (nat_pre_in2out_node) = {
1618   .name = "nat-pre-in2out",
1619   .vector_size = sizeof (u32),
1620   .sibling_of = "nat-default",
1621   .format_trace = format_nat_pre_trace,
1622   .type = VLIB_NODE_TYPE_INTERNAL,
1623   .n_errors = 0,
1624 };
1625 /* *INDENT-ON* */
1626
1627 /*
1628  * fd.io coding-style-patch-verification: ON
1629  *
1630  * Local Variables:
1631  * eval: (c-set-style "gnu")
1632  * End:
1633  */