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/ip/ip.h>
  23 #include <vnet/ethernet/ethernet.h>
  24 #include <vnet/fib/ip4_fib.h>
  25 #include <vnet/udp/udp_local.h>
  26 #include <vppinfra/error.h>
  27 #include <nat/nat.h>
  28 #include <nat/lib/ipfix_logging.h>
  29 #include <nat/nat_inlines.h>
  30 #include <nat/nat44/inlines.h>
  31 #include <nat/lib/nat_syslog.h>
  32 #include <nat/nat_ha.h>
  33 #include <nat/nat44/ed_inlines.h>
  34 #include <nat/lib/nat_inlines.h>
  35
  36 /* number of attempts to get a port for ED overloading algorithm, if rolling
  37  * a dice this many times doesn't produce a free port, it's treated
  38  * as if there were no free ports available to conserve resources */
  39 #define ED_PORT_ALLOC_ATTEMPTS (10)
  40
  41 static char *nat_in2out_ed_error_strings[] = {
  42 #define _(sym,string) string,
  43   foreach_nat_in2out_ed_error
  44 #undef _
  45 };
  46
  47 typedef struct
  48 {
  49   u32 sw_if_index;
  50   u32 next_index;
  51   u32 session_index;
  52   u32 is_slow_path;
  53 } nat_in2out_ed_trace_t;
  54
  55 static u8 *
  56 format_nat_in2out_ed_trace (u8 * s, va_list * args)
  57 {
  58   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  59   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  60   nat_in2out_ed_trace_t *t = va_arg (*args, nat_in2out_ed_trace_t *);
  61   char *tag;
  62
  63   tag =
  64     t->is_slow_path ? "NAT44_IN2OUT_ED_SLOW_PATH" :
  65     "NAT44_IN2OUT_ED_FAST_PATH";
  66
  67   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  68               t->sw_if_index, t->next_index, t->session_index);
  69
  70   return s;
  71 }
  72
  73 #ifndef CLIB_MARCH_VARIANT
  74 int
  75 nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  76 {
  77   snat_main_t *sm = &snat_main;
  78   nat44_is_idle_session_ctx_t *ctx = arg;
  79   snat_session_t *s;
  80   u64 sess_timeout_time;
  81   u8 proto;
  82   u16 r_port, l_port;
  83   ip4_address_t *l_addr, *r_addr;
  84   u32 fib_index;
  85   clib_bihash_kv_16_8_t ed_kv;
  86   int i;
  87   snat_address_t *a;
  88   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
  89                                                        ctx->thread_index);
  90
  91   ASSERT (ctx->thread_index == ed_value_get_thread_index (kv));
  92   s = pool_elt_at_index (tsm->sessions, ed_value_get_session_index (kv));
  93   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
  94   if (ctx->now >= sess_timeout_time)
  95     {
  96       if (is_fwd_bypass_session (s))
  97         goto delete;
  98
  99       l_addr = &s->out2in.addr;
 100       r_addr = &s->ext_host_addr;
 101       fib_index = s->out2in.fib_index;
 102       if (snat_is_unk_proto_session (s))
 103         {
 104           proto = s->in2out.port;
 105           r_port = 0;
 106           l_port = 0;
 107         }
 108       else
 109         {
 110           proto = nat_proto_to_ip_proto (s->nat_proto);
 111           l_port = s->out2in.port;
 112           r_port = s->ext_host_port;
 113         }
 114       init_ed_k (&ed_kv, *l_addr, l_port, *r_addr, r_port, fib_index, proto);
 115       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &ed_kv, 0))
 116         nat_elog_warn ("out2in_ed key del failed");
 117
 118       if (snat_is_unk_proto_session (s))
 119         goto delete;
 120
 121       nat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 122                                           s->in2out.addr.as_u32,
 123                                           s->out2in.addr.as_u32,
 124                                           s->nat_proto,
 125                                           s->in2out.port,
 126                                           s->out2in.port,
 127                                           s->in2out.fib_index);
 128
 129       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 130                              &s->in2out.addr, s->in2out.port,
 131                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 132                              &s->out2in.addr, s->out2in.port,
 133                              &s->ext_host_addr, s->ext_host_port,
 134                              s->nat_proto, is_twice_nat_session (s));
 135
 136       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 137                    s->ext_host_port, s->nat_proto, s->out2in.fib_index,
 138                    ctx->thread_index);
 139
 140       if (is_twice_nat_session (s))
 141         {
 142           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 143             {
 144               // TODO FIXME this is obviously broken - which address should be
 145               // freed here?!
 146               a = sm->twice_nat_addresses + i;
 147               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 148                 {
 149                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 150                                                       ctx->thread_index,
 151                                                       &s->ext_host_nat_addr,
 152                                                       s->ext_host_nat_port,
 153                                                       s->nat_proto);
 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.addr, s->out2in.port,
 164                                           s->nat_proto);
 165     delete:
 166       nat_ed_session_delete (sm, s, ctx->thread_index, 1);
 167       return 1;
 168     }
 169
 170   return 0;
 171 }
 172 #endif
 173
 174 static inline u32
 175 icmp_in2out_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 176                           ip4_header_t * ip0, icmp46_header_t * icmp0,
 177                           u32 sw_if_index0, u32 rx_fib_index0,
 178                           vlib_node_runtime_t * node, u32 next0, f64 now,
 179                           u32 thread_index, snat_session_t ** p_s0)
 180 {
 181   vlib_main_t *vm = vlib_get_main ();
 182
 183   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 184                        next0, thread_index, p_s0, 0);
 185   snat_session_t *s0 = *p_s0;
 186   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
 187     {
 188       /* Accounting */
 189       nat44_session_update_counters (s0, now,
 190                                      vlib_buffer_length_in_chain
 191                                      (vm, b0), thread_index);
 192       /* Per-user LRU list maintenance */
 193       nat44_session_update_lru (sm, s0, thread_index);
 194     }
 195   return next0;
 196 }
 197
 198 static int
 199 nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
 200                             u32 nat_proto, u32 thread_index,
 201                             ip4_address_t r_addr, u16 r_port, u8 proto,
 202                             u16 port_per_thread, u32 snat_thread_index,
 203                             snat_session_t * s,
 204                             ip4_address_t * outside_addr,
 205                             u16 * outside_port,
 206                             clib_bihash_kv_16_8_t * out2in_ed_kv)
 207 {
 208   int i;
 209   snat_address_t *a, *ga = 0;
 210   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 211
 212   const u16 port_thread_offset = (port_per_thread * snat_thread_index) + 1024;
 213
 214   for (i = 0; i < vec_len (sm->addresses); i++)
 215     {
 216       a = sm->addresses + i;
 217       switch (nat_proto)
 218         {
 219 #define _(N, j, n, unused)                                                   \
 220   case NAT_PROTOCOL_##N:                                                     \
 221     if (a->fib_index == rx_fib_index)                                        \
 222       {                                                                      \
 223         /* first try port suggested by caller */                             \
 224         u16 port = clib_net_to_host_u16 (*outside_port);                     \
 225         u16 port_offset = port - port_thread_offset;                         \
 226         if (port <= port_thread_offset ||                                    \
 227             port > port_thread_offset + port_per_thread)                     \
 228           {                                                                  \
 229             /* need to pick a different port, suggested port doesn't fit in  \
 230              * this thread's port range */                                   \
 231             port_offset = snat_random_port (0, port_per_thread - 1);         \
 232             port = port_thread_offset + port_offset;                         \
 233           }                                                                  \
 234         u16 attempts = ED_PORT_ALLOC_ATTEMPTS;                               \
 235         do                                                                   \
 236           {                                                                  \
 237             init_ed_kv (out2in_ed_kv, a->addr, clib_host_to_net_u16 (port),  \
 238                         r_addr, r_port, s->out2in.fib_index, proto,          \
 239                         thread_index, s - tsm->sessions);                    \
 240             int rv = clib_bihash_add_del_16_8 (&sm->out2in_ed, out2in_ed_kv, \
 241                                                2 /* is_add */);              \
 242             if (0 == rv)                                                     \
 243               {                                                              \
 244                 ++a->busy_##n##_port_refcounts[port];                        \
 245                 a->busy_##n##_ports_per_thread[thread_index]++;              \
 246                 a->busy_##n##_ports++;                                       \
 247                 *outside_addr = a->addr;                                     \
 248                 *outside_port = clib_host_to_net_u16 (port);                 \
 249                 return 0;                                                    \
 250               }                                                              \
 251             port_offset = snat_random_port (0, port_per_thread - 1);         \
 252             port = port_thread_offset + port_offset;                         \
 253             --attempts;                                                      \
 254           }                                                                  \
 255         while (attempts > 0);                                                \
 256       }                                                                      \
 257     else if (a->fib_index == ~0)                                             \
 258       {                                                                      \
 259         ga = a;                                                              \
 260       }                                                                      \
 261     break;
 262
 263           foreach_nat_protocol;
 264         default:
 265           nat_elog_info ("unknown protocol");
 266           return 1;
 267         }
 268     }
 269
 270   if (ga)
 271     {
 272       /* fake fib_index to reuse macro */
 273       rx_fib_index = ~0;
 274       a = ga;
 275       switch (nat_proto)
 276         {
 277           foreach_nat_protocol;
 278         default:
 279           nat_elog_info ("unknown protocol");
 280           return 1;
 281         }
 282     }
 283
 284 #undef _
 285
 286   /* Totally out of translations to use... */
 287   nat_ipfix_logging_addresses_exhausted (thread_index, 0);
 288   return 1;
 289 }
 290
 291 static_always_inline u32
 292 nat_outside_fib_index_lookup (snat_main_t * sm, ip4_address_t addr)
 293 {
 294   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 295   nat_outside_fib_t *outside_fib;
 296   fib_prefix_t pfx = {
 297     .fp_proto = FIB_PROTOCOL_IP4,
 298     .fp_len = 32,
 299     .fp_addr = {.ip4.as_u32 = addr.as_u32,}
 300     ,
 301   };
 302   // TODO: multiple vrfs none can resolve addr
 303   /* *INDENT-OFF* */
 304   vec_foreach (outside_fib, sm->outside_fibs)
 305     {
 306       fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 307       if (FIB_NODE_INDEX_INVALID != fei)
 308         {
 309           if (fib_entry_get_resolving_interface (fei) != ~0)
 310             {
 311               return outside_fib->fib_index;
 312             }
 313         }
 314     }
 315   /* *INDENT-ON* */
 316   return ~0;
 317 }
 318
 319 static u32
 320 slow_path_ed (snat_main_t * sm,
 321               vlib_buffer_t * b,
 322               ip4_address_t l_addr,
 323               ip4_address_t r_addr,
 324               u16 l_port,
 325               u16 r_port,
 326               u8 proto,
 327               u32 rx_fib_index,
 328               snat_session_t ** sessionp,
 329               vlib_node_runtime_t * node, u32 next, u32 thread_index, f64 now)
 330 {
 331   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 332   clib_bihash_kv_16_8_t out2in_ed_kv;
 333   nat44_is_idle_session_ctx_t ctx;
 334   ip4_address_t outside_addr;
 335   u16 outside_port;
 336   u8 identity_nat;
 337
 338   u32 nat_proto = ip_proto_to_nat_proto (proto);
 339   snat_session_t *s = NULL;
 340   lb_nat_type_t lb = 0;
 341
 342   if (PREDICT_TRUE (nat_proto == NAT_PROTOCOL_TCP))
 343     {
 344       if (PREDICT_FALSE
 345           (!tcp_flags_is_init
 346            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 347         {
 348           b->error = node->errors[NAT_IN2OUT_ED_ERROR_NON_SYN];
 349           return NAT_NEXT_DROP;
 350         }
 351     }
 352
 353   if (PREDICT_FALSE
 354       (nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index)))
 355     {
 356       if (!nat_lru_free_one (sm, thread_index, now))
 357         {
 358           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 359           nat_ipfix_logging_max_sessions (thread_index,
 360                                           sm->max_translations_per_thread);
 361           nat_elog_notice ("maximum sessions exceeded");
 362           return NAT_NEXT_DROP;
 363         }
 364     }
 365
 366   ip4_address_t sm_addr;
 367   u16 sm_port;
 368   u32 sm_fib_index;
 369   /* First try to match static mapping by local address and port */
 370   if (snat_static_mapping_match
 371       (sm, l_addr, l_port, rx_fib_index, nat_proto, &sm_addr, &sm_port,
 372        &sm_fib_index, 0, 0, 0, &lb, 0, &identity_nat, 0))
 373     {
 374       s = nat_ed_session_alloc (sm, thread_index, now, proto);
 375       ASSERT (s);
 376       s->in2out.addr = l_addr;
 377       s->in2out.port = l_port;
 378       s->nat_proto = nat_proto;
 379       s->in2out.fib_index = rx_fib_index;
 380       s->out2in.fib_index = sm->outside_fib_index;
 381
 382       switch (vec_len (sm->outside_fibs))
 383         {
 384         case 0:
 385           s->out2in.fib_index = sm->outside_fib_index;
 386           break;
 387         case 1:
 388           s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 389           break;
 390         default:
 391           s->out2in.fib_index = nat_outside_fib_index_lookup (sm, r_addr);
 392           break;
 393         }
 394
 395       /* Try to create dynamic translation */
 396       outside_port = l_port;    // suggest using local port to allocation function
 397       if (nat_ed_alloc_addr_and_port (sm, rx_fib_index, nat_proto,
 398                                       thread_index, r_addr, r_port, proto,
 399                                       sm->port_per_thread,
 400                                       tsm->snat_thread_index, s,
 401                                       &outside_addr,
 402                                       &outside_port, &out2in_ed_kv))
 403         {
 404           nat_elog_notice ("addresses exhausted");
 405           b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 406           nat_ed_session_delete (sm, s, thread_index, 1);
 407           return NAT_NEXT_DROP;
 408         }
 409       s->out2in.addr = outside_addr;
 410       s->out2in.port = outside_port;
 411     }
 412   else
 413     {
 414       if (PREDICT_FALSE (identity_nat))
 415         {
 416           *sessionp = NULL;
 417           return next;
 418         }
 419       s = nat_ed_session_alloc (sm, thread_index, now, proto);
 420       ASSERT (s);
 421       s->out2in.addr = sm_addr;
 422       s->out2in.port = sm_port;
 423       s->in2out.addr = l_addr;
 424       s->in2out.port = l_port;
 425       s->nat_proto = nat_proto;
 426       s->in2out.fib_index = rx_fib_index;
 427       s->out2in.fib_index = sm->outside_fib_index;
 428       switch (vec_len (sm->outside_fibs))
 429         {
 430         case 0:
 431           s->out2in.fib_index = sm->outside_fib_index;
 432           break;
 433         case 1:
 434           s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 435           break;
 436         default:
 437           s->out2in.fib_index = nat_outside_fib_index_lookup (sm, r_addr);
 438           break;
 439         }
 440
 441       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 442
 443       init_ed_kv (&out2in_ed_kv, sm_addr, sm_port, r_addr, r_port,
 444                   s->out2in.fib_index, proto, thread_index,
 445                   s - tsm->sessions);
 446       if (clib_bihash_add_or_overwrite_stale_16_8
 447           (&sm->out2in_ed, &out2in_ed_kv, nat44_o2i_ed_is_idle_session_cb,
 448            &ctx))
 449         nat_elog_notice ("out2in-ed key add failed");
 450     }
 451
 452   if (lb)
 453     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 454   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 455   s->ext_host_addr = r_addr;
 456   s->ext_host_port = r_port;
 457
 458   clib_bihash_kv_16_8_t in2out_ed_kv;
 459   init_ed_kv (&in2out_ed_kv, l_addr, l_port, r_addr, r_port, rx_fib_index,
 460               proto, thread_index, s - tsm->sessions);
 461   ctx.now = now;
 462   ctx.thread_index = thread_index;
 463   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &in2out_ed_kv,
 464                                                nat44_i2o_ed_is_idle_session_cb,
 465                                                &ctx))
 466     nat_elog_notice ("in2out-ed key add failed");
 467
 468   *sessionp = s;
 469
 470   /* log NAT event */
 471   nat_ipfix_logging_nat44_ses_create (thread_index,
 472                                       s->in2out.addr.as_u32,
 473                                       s->out2in.addr.as_u32,
 474                                       s->nat_proto,
 475                                       s->in2out.port,
 476                                       s->out2in.port, s->in2out.fib_index);
 477
 478   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 479                          &s->in2out.addr, s->in2out.port,
 480                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 481                          &s->out2in.addr, s->out2in.port,
 482                          &s->ext_host_addr, s->ext_host_port, s->nat_proto,
 483                          0);
 484
 485   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 486                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 487                &s->ext_host_nat_addr, s->ext_host_nat_port,
 488                s->nat_proto, s->in2out.fib_index, s->flags, thread_index, 0);
 489
 490   per_vrf_sessions_register_session (s, thread_index);
 491
 492   return next;
 493 }
 494
 495 static_always_inline int
 496 nat44_ed_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 497                         u32 sw_if_index, ip4_header_t * ip, u32 proto,
 498                         u32 rx_fib_index, u32 thread_index)
 499 {
 500   udp_header_t *udp = ip4_next_header (ip);
 501   clib_bihash_kv_16_8_t kv, value;
 502
 503   init_ed_k (&kv, ip->dst_address, udp->dst_port, ip->src_address,
 504              udp->src_port, sm->outside_fib_index, ip->protocol);
 505
 506   /* NAT packet aimed at external address if has active sessions */
 507   if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 508     {
 509       /* or is static mappings */
 510       ip4_address_t placeholder_addr;
 511       u16 placeholder_port;
 512       u32 placeholder_fib_index;
 513       if (!snat_static_mapping_match
 514           (sm, ip->dst_address, udp->dst_port, sm->outside_fib_index, proto,
 515            &placeholder_addr, &placeholder_port, &placeholder_fib_index, 1, 0,
 516            0, 0, 0, 0, 0))
 517         return 0;
 518     }
 519   else
 520     return 0;
 521
 522   if (sm->forwarding_enabled)
 523     return 1;
 524
 525   return snat_not_translate_fast (sm, node, sw_if_index, ip, proto,
 526                                   rx_fib_index);
 527 }
 528
 529 static_always_inline int
 530 nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
 531                                       u32 thread_index, f64 now,
 532                                       vlib_main_t * vm, vlib_buffer_t * b)
 533 {
 534   clib_bihash_kv_16_8_t kv, value;
 535   snat_session_t *s = 0;
 536   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 537
 538   if (!sm->forwarding_enabled)
 539     return 0;
 540
 541   if (ip->protocol == IP_PROTOCOL_ICMP)
 542     {
 543       if (get_icmp_i2o_ed_key (b, ip, 0, ~0, ~0, 0, 0, 0, &kv))
 544         return 0;
 545     }
 546   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 547     {
 548       init_ed_k (&kv, ip->src_address, vnet_buffer (b)->ip.reass.l4_src_port,
 549                  ip->dst_address, vnet_buffer (b)->ip.reass.l4_dst_port, 0,
 550                  ip->protocol);
 551     }
 552   else
 553     {
 554       init_ed_k (&kv, ip->src_address, 0, ip->dst_address, 0, 0,
 555                  ip->protocol);
 556     }
 557
 558   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 559     {
 560       ASSERT (thread_index == ed_value_get_thread_index (&value));
 561       s =
 562         pool_elt_at_index (tsm->sessions,
 563                            ed_value_get_session_index (&value));
 564       if (is_fwd_bypass_session (s))
 565         {
 566           if (ip->protocol == IP_PROTOCOL_TCP)
 567             {
 568               nat44_set_tcp_session_state_i2o (sm, now, s, b, thread_index);
 569             }
 570           /* Accounting */
 571           nat44_session_update_counters (s, now,
 572                                          vlib_buffer_length_in_chain (vm, b),
 573                                          thread_index);
 574           /* Per-user LRU list maintenance */
 575           nat44_session_update_lru (sm, s, thread_index);
 576           return 1;
 577         }
 578       else
 579         return 0;
 580     }
 581
 582   return 0;
 583 }
 584
 585 static_always_inline int
 586 nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
 587                                        u16 src_port, u16 dst_port,
 588                                        u32 thread_index, u32 rx_sw_if_index,
 589                                        u32 tx_sw_if_index)
 590 {
 591   clib_bihash_kv_16_8_t kv, value;
 592   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 593   snat_interface_t *i;
 594   snat_session_t *s;
 595   u32 rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (rx_sw_if_index);
 596   u32 tx_fib_index = ip4_fib_table_get_index_for_sw_if_index (tx_sw_if_index);
 597
 598   /* src NAT check */
 599   init_ed_k (&kv, ip->src_address, src_port, ip->dst_address, dst_port,
 600              tx_fib_index, ip->protocol);
 601   if (!clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
 602     {
 603       ASSERT (thread_index == ed_value_get_thread_index (&value));
 604       s =
 605         pool_elt_at_index (tsm->sessions,
 606                            ed_value_get_session_index (&value));
 607       if (nat44_is_ses_closed (s))
 608         {
 609           nat_free_session_data (sm, s, thread_index, 0);
 610           nat_ed_session_delete (sm, s, thread_index, 1);
 611         }
 612       else
 613         s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
 614       return 1;
 615     }
 616
 617   /* dst NAT check */
 618   init_ed_k (&kv, ip->dst_address, dst_port, ip->src_address, src_port,
 619              rx_fib_index, ip->protocol);
 620   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 621     {
 622       ASSERT (thread_index == ed_value_get_thread_index (&value));
 623       s =
 624         pool_elt_at_index (tsm->sessions,
 625                            ed_value_get_session_index (&value));
 626       if (is_fwd_bypass_session (s))
 627         return 0;
 628
 629       /* hairpinning */
 630       /* *INDENT-OFF* */
 631       pool_foreach (i, sm->output_feature_interfaces,
 632       ({
 633         if ((nat_interface_is_inside (i)) && (rx_sw_if_index == i->sw_if_index))
 634            return 0;
 635       }));
 636       /* *INDENT-ON* */
 637       return 1;
 638     }
 639
 640   return 0;
 641 }
 642
 643 #ifndef CLIB_MARCH_VARIANT
 644 u32
 645 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 646                       u32 thread_index, vlib_buffer_t * b,
 647                       ip4_header_t * ip, ip4_address_t * addr,
 648                       u16 * port, u32 * fib_index, nat_protocol_t * proto,
 649                       void *d, void *e, u8 * dont_translate)
 650 {
 651   u32 sw_if_index;
 652   u32 rx_fib_index;
 653   clib_bihash_kv_16_8_t kv, value;
 654   u32 next = ~0;
 655   int err;
 656   snat_session_t *s = NULL;
 657   u16 l_port = 0, r_port = 0;   // initialize to workaround gcc warning
 658   vlib_main_t *vm = vlib_get_main ();
 659   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 660   *dont_translate = 0;
 661
 662   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 663   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 664
 665   err =
 666     get_icmp_i2o_ed_key (b, ip, rx_fib_index, ~0, ~0, proto, &l_port,
 667                          &r_port, &kv);
 668   if (err != 0)
 669     {
 670       b->error = node->errors[err];
 671       next = NAT_NEXT_DROP;
 672       goto out;
 673     }
 674
 675   if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 676     {
 677       if (vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0)
 678         {
 679           if (PREDICT_FALSE
 680               (nat44_ed_not_translate_output_feature
 681                (sm, ip, l_port, r_port, thread_index,
 682                 sw_if_index, vnet_buffer (b)->sw_if_index[VLIB_TX])))
 683             {
 684               *dont_translate = 1;
 685               goto out;
 686             }
 687         }
 688       else
 689         {
 690           if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
 691                                                      ip, NAT_PROTOCOL_ICMP,
 692                                                      rx_fib_index,
 693                                                      thread_index)))
 694             {
 695               *dont_translate = 1;
 696               goto out;
 697             }
 698         }
 699
 700       if (PREDICT_FALSE
 701           (icmp_type_is_error_message
 702            (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)))
 703         {
 704           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 705           next = NAT_NEXT_DROP;
 706           goto out;
 707         }
 708
 709       next =
 710         slow_path_ed (sm, b, ip->src_address, ip->dst_address, l_port, r_port,
 711                       ip->protocol, rx_fib_index, &s, node, next,
 712                       thread_index, vlib_time_now (vm));
 713
 714       if (PREDICT_FALSE (next == NAT_NEXT_DROP))
 715         goto out;
 716
 717       if (!s)
 718         {
 719           *dont_translate = 1;
 720           goto out;
 721         }
 722     }
 723   else
 724     {
 725       if (PREDICT_FALSE
 726           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 727            ICMP4_echo_request
 728            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 729            ICMP4_echo_reply
 730            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 731                                            reass.icmp_type_or_tcp_flags)))
 732         {
 733           b->error = node->errors[NAT_IN2OUT_ED_ERROR_BAD_ICMP_TYPE];
 734           next = NAT_NEXT_DROP;
 735           goto out;
 736         }
 737
 738       ASSERT (thread_index == ed_value_get_thread_index (&value));
 739       s =
 740         pool_elt_at_index (tsm->sessions,
 741                            ed_value_get_session_index (&value));
 742     }
 743 out:
 744   if (s)
 745     {
 746       *addr = s->out2in.addr;
 747       *port = s->out2in.port;
 748       *fib_index = s->out2in.fib_index;
 749     }
 750   if (d)
 751     {
 752       *(snat_session_t **) d = s;
 753     }
 754   return next;
 755 }
 756 #endif
 757
 758 static snat_session_t *
 759 nat44_ed_in2out_unknown_proto (snat_main_t * sm,
 760                                vlib_buffer_t * b,
 761                                ip4_header_t * ip,
 762                                u32 rx_fib_index,
 763                                u32 thread_index,
 764                                f64 now,
 765                                vlib_main_t * vm, vlib_node_runtime_t * node)
 766 {
 767   clib_bihash_kv_8_8_t kv, value;
 768   clib_bihash_kv_16_8_t s_kv, s_value;
 769   snat_static_mapping_t *m;
 770   u32 old_addr, new_addr = 0;
 771   ip_csum_t sum;
 772   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 773   snat_session_t *s;
 774   u32 outside_fib_index = sm->outside_fib_index;
 775   int i;
 776   u8 is_sm = 0;
 777
 778   switch (vec_len (sm->outside_fibs))
 779     {
 780     case 0:
 781       outside_fib_index = sm->outside_fib_index;
 782       break;
 783     case 1:
 784       outside_fib_index = sm->outside_fibs[0].fib_index;
 785       break;
 786     default:
 787       outside_fib_index = nat_outside_fib_index_lookup (sm, ip->dst_address);
 788       break;
 789     }
 790   old_addr = ip->src_address.as_u32;
 791
 792   init_ed_k (&s_kv, ip->src_address, 0, ip->dst_address, 0, rx_fib_index,
 793              ip->protocol);
 794
 795   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &s_kv, &s_value))
 796     {
 797       ASSERT (thread_index == ed_value_get_thread_index (&s_value));
 798       s =
 799         pool_elt_at_index (tsm->sessions,
 800                            ed_value_get_session_index (&s_value));
 801       new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 802     }
 803   else
 804     {
 805       if (PREDICT_FALSE
 806           (nat44_ed_maximum_sessions_exceeded
 807            (sm, rx_fib_index, thread_index)))
 808         {
 809           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 810           nat_ipfix_logging_max_sessions (thread_index,
 811                                           sm->max_translations_per_thread);
 812           nat_elog_notice ("maximum sessions exceeded");
 813           return 0;
 814         }
 815
 816       init_nat_k (&kv, ip->src_address, 0, rx_fib_index, 0);
 817
 818       /* Try to find static mapping first */
 819       if (!clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 820         {
 821           m = pool_elt_at_index (sm->static_mappings, value.value);
 822           new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 823           is_sm = 1;
 824           goto create_ses;
 825         }
 826       else
 827         {
 828           /* *INDENT-OFF* */
 829           pool_foreach (s, tsm->sessions, {
 830             if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
 831               {
 832                 new_addr = ip->src_address.as_u32 = s->out2in.addr.as_u32;
 833
 834                 init_ed_k(&s_kv, s->out2in.addr, 0, ip->dst_address, 0, outside_fib_index, ip->protocol);
 835                 if (clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
 836                   goto create_ses;
 837
 838                 break;
 839               }
 840           });
 841           /* *INDENT-ON* */
 842
 843           for (i = 0; i < vec_len (sm->addresses); i++)
 844             {
 845               init_ed_k (&s_kv, sm->addresses[i].addr, 0, ip->dst_address, 0,
 846                          outside_fib_index, ip->protocol);
 847               if (clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
 848                 {
 849                   new_addr = ip->src_address.as_u32 =
 850                     sm->addresses[i].addr.as_u32;
 851                   goto create_ses;
 852                 }
 853             }
 854           return 0;
 855         }
 856
 857     create_ses:
 858       s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
 859       if (!s)
 860         {
 861           b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 862           nat_elog_warn ("create NAT session failed");
 863           return 0;
 864         }
 865
 866       s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
 867       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 868       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 869       s->out2in.addr.as_u32 = new_addr;
 870       s->out2in.fib_index = outside_fib_index;
 871       s->in2out.addr.as_u32 = old_addr;
 872       s->in2out.fib_index = rx_fib_index;
 873       s->in2out.port = s->out2in.port = ip->protocol;
 874       if (is_sm)
 875         s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 876
 877       /* Add to lookup tables */
 878       init_ed_kv (&s_kv, s->in2out.addr, 0, ip->dst_address, 0, rx_fib_index,
 879                   ip->protocol, thread_index, s - tsm->sessions);
 880       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 881         nat_elog_notice ("in2out key add failed");
 882
 883       init_ed_kv (&s_kv, s->out2in.addr, 0, ip->dst_address, 0,
 884                   outside_fib_index, ip->protocol, thread_index,
 885                   s - tsm->sessions);
 886       if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &s_kv, 1))
 887         nat_elog_notice ("out2in key add failed");
 888
 889       per_vrf_sessions_register_session (s, thread_index);
 890     }
 891
 892   /* Update IP checksum */
 893   sum = ip->checksum;
 894   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 895   ip->checksum = ip_csum_fold (sum);
 896
 897   /* Accounting */
 898   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 899                                  thread_index);
 900   /* Per-user LRU list maintenance */
 901   nat44_session_update_lru (sm, s, thread_index);
 902
 903   /* Hairpinning */
 904   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 905     nat44_ed_hairpinning_unknown_proto (sm, b, ip);
 906
 907   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 908     vnet_buffer (b)->sw_if_index[VLIB_TX] = outside_fib_index;
 909
 910   return s;
 911 }
 912
 913 static inline uword
 914 nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 915                                           vlib_node_runtime_t * node,
 916                                           vlib_frame_t * frame,
 917                                           int is_output_feature)
 918 {
 919   u32 n_left_from, *from;
 920   snat_main_t *sm = &snat_main;
 921   f64 now = vlib_time_now (vm);
 922   u32 thread_index = vm->thread_index;
 923   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 924   u32 def_slow = is_output_feature ? NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH
 925     : NAT_NEXT_IN2OUT_ED_SLOW_PATH;
 926
 927   from = vlib_frame_vector_args (frame);
 928   n_left_from = frame->n_vectors;
 929
 930   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 931   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 932   vlib_get_buffers (vm, from, b, n_left_from);
 933
 934   while (n_left_from > 0)
 935     {
 936       vlib_buffer_t *b0;
 937       u32 sw_if_index0, rx_fib_index0, proto0, new_addr0, old_addr0,
 938         iph_offset0 = 0;
 939       u16 old_port0, new_port0;
 940       ip4_header_t *ip0;
 941       udp_header_t *udp0;
 942       tcp_header_t *tcp0;
 943       snat_session_t *s0 = 0;
 944       clib_bihash_kv_16_8_t kv0, value0;
 945       ip_csum_t sum0;
 946
 947       b0 = *b;
 948       b++;
 949
 950       /* Prefetch next iteration. */
 951       if (PREDICT_TRUE (n_left_from >= 2))
 952         {
 953           vlib_buffer_t *p2;
 954
 955           p2 = *b;
 956
 957           vlib_prefetch_buffer_header (p2, LOAD);
 958
 959           CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
 960         }
 961
 962       if (is_output_feature)
 963         {
 964           iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 965         }
 966
 967       next[0] = vnet_buffer2 (b0)->nat.arc_next;
 968
 969       ip0 =
 970         (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) + iph_offset0);
 971
 972       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 973       rx_fib_index0 =
 974         fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
 975
 976       if (PREDICT_FALSE (ip0->ttl == 1))
 977         {
 978           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 979           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 980                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
 981                                        0);
 982           next[0] = NAT_NEXT_ICMP_ERROR;
 983           goto trace0;
 984         }
 985
 986       udp0 = ip4_next_header (ip0);
 987       tcp0 = (tcp_header_t *) udp0;
 988       proto0 = ip_proto_to_nat_proto (ip0->protocol);
 989
 990       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 991         {
 992           next[0] = def_slow;
 993           goto trace0;
 994         }
 995
 996       if (is_output_feature)
 997         {
 998           if (PREDICT_FALSE
 999               (nat_not_translate_output_feature_fwd
1000                (sm, ip0, thread_index, now, vm, b0)))
1001             goto trace0;
1002         }
1003
1004       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1005         {
1006           next[0] = def_slow;
1007           goto trace0;
1008         }
1009
1010       init_ed_k (&kv0, ip0->src_address,
1011                  vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address,
1012                  vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
1013                  ip0->protocol);
1014
1015       // lookup for session
1016       if (clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1017         {
1018           // session does not exist go slow path
1019           next[0] = def_slow;
1020           goto trace0;
1021         }
1022       ASSERT (thread_index == ed_value_get_thread_index (&value0));
1023       s0 =
1024         pool_elt_at_index (tsm->sessions,
1025                            ed_value_get_session_index (&value0));
1026
1027       if (PREDICT_FALSE (per_vrf_sessions_is_expired (s0, thread_index)))
1028         {
1029           // session is closed, go slow path
1030           nat_free_session_data (sm, s0, thread_index, 0);
1031           nat_ed_session_delete (sm, s0, thread_index, 1);
1032           next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1033           goto trace0;
1034         }
1035
1036       if (s0->tcp_closed_timestamp)
1037         {
1038           if (now >= s0->tcp_closed_timestamp)
1039             {
1040               // session is closed, go slow path, freed in slow path
1041               next[0] = def_slow;
1042             }
1043           else
1044             {
1045               // session in transitory timeout, drop
1046               b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TCP_CLOSED];
1047               next[0] = NAT_NEXT_DROP;
1048             }
1049           goto trace0;
1050         }
1051
1052       // drop if session expired
1053       u64 sess_timeout_time;
1054       sess_timeout_time =
1055         s0->last_heard + (f64) nat44_session_get_timeout (sm, s0);
1056       if (now >= sess_timeout_time)
1057         {
1058           nat_free_session_data (sm, s0, thread_index, 0);
1059           nat_ed_session_delete (sm, s0, thread_index, 1);
1060           // session is closed, go slow path
1061           next[0] = def_slow;
1062           goto trace0;
1063         }
1064
1065       b0->flags |= VNET_BUFFER_F_IS_NATED;
1066
1067       if (!is_output_feature)
1068         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1069
1070       old_addr0 = ip0->src_address.as_u32;
1071       new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1072       sum0 = ip0->checksum;
1073       sum0 =
1074         ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1075                         src_address);
1076       if (PREDICT_FALSE (is_twice_nat_session (s0)))
1077         sum0 =
1078           ip_csum_update (sum0, ip0->dst_address.as_u32,
1079                           s0->ext_host_addr.as_u32, ip4_header_t,
1080                           dst_address);
1081       ip0->checksum = ip_csum_fold (sum0);
1082
1083       old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1084
1085       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1086         {
1087           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1088             {
1089               new_port0 = udp0->src_port = s0->out2in.port;
1090               sum0 = tcp0->checksum;
1091               sum0 =
1092                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1093                                 dst_address);
1094               sum0 =
1095                 ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1096                                 length);
1097               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1098                 {
1099                   sum0 =
1100                     ip_csum_update (sum0, ip0->dst_address.as_u32,
1101                                     s0->ext_host_addr.as_u32, ip4_header_t,
1102                                     dst_address);
1103                   sum0 =
1104                     ip_csum_update (sum0,
1105                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1106                                     s0->ext_host_port, ip4_header_t, length);
1107                   tcp0->dst_port = s0->ext_host_port;
1108                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1109                 }
1110               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1111               tcp0->checksum = ip_csum_fold (sum0);
1112             }
1113           vlib_increment_simple_counter (&sm->counters.fastpath.in2out_ed.tcp,
1114                                          thread_index, sw_if_index0, 1);
1115           nat44_set_tcp_session_state_i2o (sm, now, s0, b0, thread_index);
1116         }
1117       else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1118                && udp0->checksum)
1119         {
1120           new_port0 = udp0->src_port = s0->out2in.port;
1121           sum0 = udp0->checksum;
1122           sum0 =
1123             ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1124                             dst_address);
1125           sum0 =
1126             ip_csum_update (sum0, old_port0, new_port0, ip4_header_t, length);
1127           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1128             {
1129               sum0 =
1130                 ip_csum_update (sum0, ip0->dst_address.as_u32,
1131                                 s0->ext_host_addr.as_u32, ip4_header_t,
1132                                 dst_address);
1133               sum0 =
1134                 ip_csum_update (sum0, vnet_buffer (b0)->ip.reass.l4_dst_port,
1135                                 s0->ext_host_port, ip4_header_t, length);
1136               udp0->dst_port = s0->ext_host_port;
1137               ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1138             }
1139           udp0->checksum = ip_csum_fold (sum0);
1140           vlib_increment_simple_counter (&sm->counters.fastpath.in2out_ed.udp,
1141                                          thread_index, sw_if_index0, 1);
1142         }
1143       else
1144         {
1145           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1146             {
1147               new_port0 = udp0->src_port = s0->out2in.port;
1148               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1149                 {
1150                   udp0->dst_port = s0->ext_host_port;
1151                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1152                 }
1153               vlib_increment_simple_counter (&sm->counters.fastpath.
1154                                              in2out_ed.udp, thread_index,
1155                                              sw_if_index0, 1);
1156             }
1157         }
1158
1159       /* Accounting */
1160       nat44_session_update_counters (s0, now,
1161                                      vlib_buffer_length_in_chain (vm, b0),
1162                                      thread_index);
1163       /* Per-user LRU list maintenance */
1164       nat44_session_update_lru (sm, s0, thread_index);
1165
1166     trace0:
1167       if (PREDICT_FALSE
1168           ((node->flags & VLIB_NODE_FLAG_TRACE)
1169            && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1170         {
1171           nat_in2out_ed_trace_t *t =
1172             vlib_add_trace (vm, node, b0, sizeof (*t));
1173           t->sw_if_index = sw_if_index0;
1174           t->next_index = next[0];
1175           t->is_slow_path = 0;
1176
1177           if (s0)
1178             t->session_index = s0 - tsm->sessions;
1179           else
1180             t->session_index = ~0;
1181         }
1182
1183       if (next[0] == NAT_NEXT_DROP)
1184         {
1185           vlib_increment_simple_counter (&sm->counters.fastpath.
1186                                          in2out_ed.drops, thread_index,
1187                                          sw_if_index0, 1);
1188         }
1189
1190       n_left_from--;
1191       next++;
1192     }
1193
1194   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1195                                frame->n_vectors);
1196   return frame->n_vectors;
1197 }
1198
1199 static inline uword
1200 nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
1201                                           vlib_node_runtime_t * node,
1202                                           vlib_frame_t * frame,
1203                                           int is_output_feature)
1204 {
1205   u32 n_left_from, *from;
1206   snat_main_t *sm = &snat_main;
1207   f64 now = vlib_time_now (vm);
1208   u32 thread_index = vm->thread_index;
1209   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
1210
1211   from = vlib_frame_vector_args (frame);
1212   n_left_from = frame->n_vectors;
1213
1214   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
1215   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
1216   vlib_get_buffers (vm, from, b, n_left_from);
1217
1218   while (n_left_from > 0)
1219     {
1220       vlib_buffer_t *b0;
1221       u32 sw_if_index0, rx_fib_index0, proto0, new_addr0, old_addr0,
1222         iph_offset0 = 0;
1223       u16 old_port0, new_port0;
1224       ip4_header_t *ip0;
1225       udp_header_t *udp0;
1226       tcp_header_t *tcp0;
1227       icmp46_header_t *icmp0;
1228       snat_session_t *s0 = 0;
1229       clib_bihash_kv_16_8_t kv0, value0;
1230       ip_csum_t sum0;
1231
1232       b0 = *b;
1233
1234       if (is_output_feature)
1235         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1236
1237       next[0] = vnet_buffer2 (b0)->nat.arc_next;
1238
1239       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1240                               iph_offset0);
1241
1242       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1243       rx_fib_index0 =
1244         fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
1245
1246       if (PREDICT_FALSE (ip0->ttl == 1))
1247         {
1248           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1249           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1250                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1251                                        0);
1252           next[0] = NAT_NEXT_ICMP_ERROR;
1253           goto trace0;
1254         }
1255
1256       udp0 = ip4_next_header (ip0);
1257       tcp0 = (tcp_header_t *) udp0;
1258       icmp0 = (icmp46_header_t *) udp0;
1259       proto0 = ip_proto_to_nat_proto (ip0->protocol);
1260
1261       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1262         {
1263           s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
1264                                               rx_fib_index0,
1265                                               thread_index, now, vm, node);
1266           if (!s0)
1267             next[0] = NAT_NEXT_DROP;
1268
1269           vlib_increment_simple_counter (&sm->counters.slowpath.
1270                                          in2out_ed.other, thread_index,
1271                                          sw_if_index0, 1);
1272           goto trace0;
1273         }
1274
1275       if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1276         {
1277           next[0] =
1278             icmp_in2out_ed_slow_path (sm, b0, ip0, icmp0, sw_if_index0,
1279                                       rx_fib_index0, node, next[0], now,
1280                                       thread_index, &s0);
1281           vlib_increment_simple_counter (&sm->counters.slowpath.
1282                                          in2out_ed.icmp, thread_index,
1283                                          sw_if_index0, 1);
1284           goto trace0;
1285         }
1286
1287       init_ed_k (&kv0, ip0->src_address,
1288                  vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address,
1289                  vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0,
1290                  ip0->protocol);
1291       if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv0, &value0))
1292         {
1293           ASSERT (thread_index == ed_value_get_thread_index (&value0));
1294           s0 =
1295             pool_elt_at_index (tsm->sessions,
1296                                ed_value_get_session_index (&value0));
1297
1298           if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
1299             {
1300               nat_free_session_data (sm, s0, thread_index, 0);
1301               nat_ed_session_delete (sm, s0, thread_index, 1);
1302               s0 = NULL;
1303             }
1304         }
1305
1306       if (!s0)
1307         {
1308           if (is_output_feature)
1309             {
1310               if (PREDICT_FALSE
1311                   (nat44_ed_not_translate_output_feature
1312                    (sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
1313                     vnet_buffer (b0)->ip.reass.l4_dst_port, thread_index,
1314                     sw_if_index0, vnet_buffer (b0)->sw_if_index[VLIB_TX])))
1315                 goto trace0;
1316
1317               /*
1318                * Send DHCP packets to the ipv4 stack, or we won't
1319                * be able to use dhcp client on the outside interface
1320                */
1321               if (PREDICT_FALSE
1322                   (proto0 == NAT_PROTOCOL_UDP
1323                    && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1324                        clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
1325                    && ip0->dst_address.as_u32 == 0xffffffff))
1326                 goto trace0;
1327             }
1328           else
1329             {
1330               if (PREDICT_FALSE
1331                   (nat44_ed_not_translate
1332                    (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1333                     thread_index)))
1334                 goto trace0;
1335             }
1336
1337           next[0] =
1338             slow_path_ed (sm, b0, ip0->src_address, ip0->dst_address,
1339                           vnet_buffer (b0)->ip.reass.l4_src_port,
1340                           vnet_buffer (b0)->ip.reass.l4_dst_port,
1341                           ip0->protocol, rx_fib_index0, &s0, node, next[0],
1342                           thread_index, now);
1343
1344           if (PREDICT_FALSE (next[0] == NAT_NEXT_DROP))
1345             goto trace0;
1346
1347           if (PREDICT_FALSE (!s0))
1348             goto trace0;
1349
1350         }
1351
1352       b0->flags |= VNET_BUFFER_F_IS_NATED;
1353
1354       if (!is_output_feature)
1355         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1356
1357       old_addr0 = ip0->src_address.as_u32;
1358       new_addr0 = ip0->src_address.as_u32 = s0->out2in.addr.as_u32;
1359       sum0 = ip0->checksum;
1360       sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1361                              src_address);
1362       if (PREDICT_FALSE (is_twice_nat_session (s0)))
1363         sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1364                                s0->ext_host_addr.as_u32, ip4_header_t,
1365                                dst_address);
1366       ip0->checksum = ip_csum_fold (sum0);
1367
1368       old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1369
1370       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1371         {
1372           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1373             {
1374               new_port0 = udp0->src_port = s0->out2in.port;
1375               sum0 = tcp0->checksum;
1376               sum0 =
1377                 ip_csum_update (sum0, old_addr0, new_addr0,
1378                                 ip4_header_t, dst_address);
1379               sum0 =
1380                 ip_csum_update (sum0, old_port0, new_port0,
1381                                 ip4_header_t, length);
1382               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1383                 {
1384                   sum0 =
1385                     ip_csum_update (sum0, ip0->dst_address.as_u32,
1386                                     s0->ext_host_addr.as_u32,
1387                                     ip4_header_t, dst_address);
1388                   sum0 =
1389                     ip_csum_update (sum0,
1390                                     vnet_buffer (b0)->ip.reass.l4_dst_port,
1391                                     s0->ext_host_port, ip4_header_t, length);
1392                   tcp0->dst_port = s0->ext_host_port;
1393                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1394                 }
1395               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1396               tcp0->checksum = ip_csum_fold (sum0);
1397             }
1398           vlib_increment_simple_counter (&sm->counters.slowpath.in2out_ed.tcp,
1399                                          thread_index, sw_if_index0, 1);
1400           nat44_set_tcp_session_state_i2o (sm, now, s0, b0, thread_index);
1401         }
1402       else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1403                && udp0->checksum)
1404         {
1405           new_port0 = udp0->src_port = s0->out2in.port;
1406           sum0 = udp0->checksum;
1407           sum0 =
1408             ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1409                             dst_address);
1410           sum0 =
1411             ip_csum_update (sum0, old_port0, new_port0, ip4_header_t, length);
1412           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1413             {
1414               sum0 = ip_csum_update (sum0, ip0->dst_address.as_u32,
1415                                      s0->ext_host_addr.as_u32,
1416                                      ip4_header_t, dst_address);
1417               sum0 =
1418                 ip_csum_update (sum0,
1419                                 vnet_buffer (b0)->ip.reass.l4_dst_port,
1420                                 s0->ext_host_port, ip4_header_t, length);
1421               udp0->dst_port = s0->ext_host_port;
1422               ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1423             }
1424           udp0->checksum = ip_csum_fold (sum0);
1425           vlib_increment_simple_counter (&sm->counters.slowpath.in2out_ed.udp,
1426                                          thread_index, sw_if_index0, 1);
1427         }
1428       else
1429         {
1430           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1431             {
1432               new_port0 = udp0->src_port = s0->out2in.port;
1433               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1434                 {
1435                   udp0->dst_port = s0->ext_host_port;
1436                   ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
1437                 }
1438               vlib_increment_simple_counter (&sm->counters.slowpath.
1439                                              in2out_ed.udp, thread_index,
1440                                              sw_if_index0, 1);
1441             }
1442         }
1443
1444       /* Accounting */
1445       nat44_session_update_counters (s0, now,
1446                                      vlib_buffer_length_in_chain
1447                                      (vm, b0), thread_index);
1448       /* Per-user LRU list maintenance */
1449       nat44_session_update_lru (sm, s0, thread_index);
1450
1451     trace0:
1452       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1453                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1454         {
1455           nat_in2out_ed_trace_t *t =
1456             vlib_add_trace (vm, node, b0, sizeof (*t));
1457           t->sw_if_index = sw_if_index0;
1458           t->next_index = next[0];
1459           t->is_slow_path = 1;
1460
1461           if (s0)
1462             t->session_index = s0 - tsm->sessions;
1463           else
1464             t->session_index = ~0;
1465         }
1466
1467       if (next[0] == NAT_NEXT_DROP)
1468         {
1469           vlib_increment_simple_counter (&sm->counters.slowpath.
1470                                          in2out_ed.drops, thread_index,
1471                                          sw_if_index0, 1);
1472         }
1473
1474       n_left_from--;
1475       next++;
1476       b++;
1477     }
1478
1479   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1480                                frame->n_vectors);
1481
1482   return frame->n_vectors;
1483 }
1484
1485 VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
1486                                      vlib_node_runtime_t * node,
1487                                      vlib_frame_t * frame)
1488 {
1489   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
1490 }
1491
1492 /* *INDENT-OFF* */
1493 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
1494   .name = "nat44-ed-in2out",
1495   .vector_size = sizeof (u32),
1496   .sibling_of = "nat-default",
1497   .format_trace = format_nat_in2out_ed_trace,
1498   .type = VLIB_NODE_TYPE_INTERNAL,
1499   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1500   .error_strings = nat_in2out_ed_error_strings,
1501   .runtime_data_bytes = sizeof (snat_runtime_t),
1502 };
1503 /* *INDENT-ON* */
1504
1505 VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
1506                                             vlib_node_runtime_t * node,
1507                                             vlib_frame_t * frame)
1508 {
1509   return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
1510 }
1511
1512 /* *INDENT-OFF* */
1513 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {
1514   .name = "nat44-ed-in2out-output",
1515   .vector_size = sizeof (u32),
1516   .sibling_of = "nat-default",
1517   .format_trace = format_nat_in2out_ed_trace,
1518   .type = VLIB_NODE_TYPE_INTERNAL,
1519   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1520   .error_strings = nat_in2out_ed_error_strings,
1521   .runtime_data_bytes = sizeof (snat_runtime_t),
1522 };
1523 /* *INDENT-ON* */
1524
1525 VLIB_NODE_FN (nat44_ed_in2out_slowpath_node) (vlib_main_t * vm,
1526                                               vlib_node_runtime_t *
1527                                               node, vlib_frame_t * frame)
1528 {
1529   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 0);
1530 }
1531
1532 /* *INDENT-OFF* */
1533 VLIB_REGISTER_NODE (nat44_ed_in2out_slowpath_node) = {
1534   .name = "nat44-ed-in2out-slowpath",
1535   .vector_size = sizeof (u32),
1536   .sibling_of = "nat-default",
1537   .format_trace = format_nat_in2out_ed_trace,
1538   .type = VLIB_NODE_TYPE_INTERNAL,
1539   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1540   .error_strings = nat_in2out_ed_error_strings,
1541   .runtime_data_bytes = sizeof (snat_runtime_t),
1542 };
1543 /* *INDENT-ON* */
1544
1545 VLIB_NODE_FN (nat44_ed_in2out_output_slowpath_node) (vlib_main_t * vm,
1546                                                      vlib_node_runtime_t
1547                                                      * node,
1548                                                      vlib_frame_t * frame)
1549 {
1550   return nat44_ed_in2out_slow_path_node_fn_inline (vm, node, frame, 1);
1551 }
1552
1553 /* *INDENT-OFF* */
1554 VLIB_REGISTER_NODE (nat44_ed_in2out_output_slowpath_node) = {
1555   .name = "nat44-ed-in2out-output-slowpath",
1556   .vector_size = sizeof (u32),
1557   .sibling_of = "nat-default",
1558   .format_trace = format_nat_in2out_ed_trace,
1559   .type = VLIB_NODE_TYPE_INTERNAL,
1560   .n_errors = ARRAY_LEN (nat_in2out_ed_error_strings),
1561   .error_strings = nat_in2out_ed_error_strings,
1562   .runtime_data_bytes = sizeof (snat_runtime_t),
1563 };
1564 /* *INDENT-ON* */
1565
1566 static u8 *
1567 format_nat_pre_trace (u8 * s, va_list * args)
1568 {
1569   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1570   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1571   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1572   return format (s, "in2out next_index %d arc_next_index %d", t->next_index,
1573                  t->arc_next_index);
1574 }
1575
1576 VLIB_NODE_FN (nat_pre_in2out_node)
1577   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1578 {
1579   return nat_pre_node_fn_inline (vm, node, frame,
1580                                  NAT_NEXT_IN2OUT_ED_FAST_PATH);
1581 }
1582
1583 VLIB_NODE_FN (nat_pre_in2out_output_node)
1584   (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
1585 {
1586   return nat_pre_node_fn_inline (vm, node, frame,
1587                                  NAT_NEXT_IN2OUT_ED_OUTPUT_FAST_PATH);
1588 }
1589
1590 /* *INDENT-OFF* */
1591 VLIB_REGISTER_NODE (nat_pre_in2out_node) = {
1592   .name = "nat-pre-in2out",
1593   .vector_size = sizeof (u32),
1594   .sibling_of = "nat-default",
1595   .format_trace = format_nat_pre_trace,
1596   .type = VLIB_NODE_TYPE_INTERNAL,
1597   .n_errors = 0,
1598 };
1599
1600 VLIB_REGISTER_NODE (nat_pre_in2out_output_node) = {
1601   .name = "nat-pre-in2out-output",
1602   .vector_size = sizeof (u32),
1603   .sibling_of = "nat-default",
1604   .format_trace = format_nat_pre_trace,
1605   .type = VLIB_NODE_TYPE_INTERNAL,
1606   .n_errors = 0,
1607 };
1608 /* *INDENT-ON* */
1609
1610 /*
1611  * fd.io coding-style-patch-verification: ON
1612  *
1613  * Local Variables:
1614  * eval: (c-set-style "gnu")
1615  * End:
1616  */