src/plugins/nat/nat44-ed/nat44_ed_inlines.h

   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  * @brief The NAT inline functions
  17  */
  18
  19 #ifndef __included_nat44_ed_inlines_h__
  20 #define __included_nat44_ed_inlines_h__
  21
  22 #include <float.h>
  23 #include <vppinfra/clib.h>
  24 #include <vnet/fib/ip4_fib.h>
  25
  26 #include <nat/lib/log.h>
  27 #include <nat/nat44-ed/nat44_ed.h>
  28
  29 always_inline u64
  30 calc_nat_key (ip4_address_t addr, u16 port, u32 fib_index, u8 proto)
  31 {
  32   ASSERT (fib_index <= (1 << 14) - 1);
  33   ASSERT (proto <= (1 << 3) - 1);
  34   return (u64) addr.as_u32 << 32 | (u64) port << 16 | fib_index << 3 |
  35          (proto & 0x7);
  36 }
  37
  38 always_inline void
  39 split_nat_key (u64 key, ip4_address_t *addr, u16 *port, u32 *fib_index,
  40                nat_protocol_t *proto)
  41 {
  42   if (addr)
  43     {
  44       addr->as_u32 = key >> 32;
  45     }
  46   if (port)
  47     {
  48       *port = (key >> 16) & (u16) ~0;
  49     }
  50   if (fib_index)
  51     {
  52       *fib_index = key >> 3 & ((1 << 13) - 1);
  53     }
  54   if (proto)
  55     {
  56       *proto = key & 0x7;
  57     }
  58 }
  59
  60 always_inline void
  61 init_nat_k (clib_bihash_kv_8_8_t *kv, ip4_address_t addr, u16 port,
  62             u32 fib_index, nat_protocol_t proto)
  63 {
  64   kv->key = calc_nat_key (addr, port, fib_index, proto);
  65   kv->value = ~0ULL;
  66 }
  67
  68 always_inline void
  69 init_nat_kv (clib_bihash_kv_8_8_t *kv, ip4_address_t addr, u16 port,
  70              u32 fib_index, nat_protocol_t proto, u32 thread_index,
  71              u32 session_index)
  72 {
  73   init_nat_k (kv, addr, port, fib_index, proto);
  74   kv->value = (u64) thread_index << 32 | session_index;
  75 }
  76
  77 always_inline void
  78 init_nat_i2o_k (clib_bihash_kv_8_8_t *kv, snat_session_t *s)
  79 {
  80   return init_nat_k (kv, s->in2out.addr, s->in2out.port, s->in2out.fib_index,
  81                      s->nat_proto);
  82 }
  83
  84 always_inline void
  85 init_nat_i2o_kv (clib_bihash_kv_8_8_t *kv, snat_session_t *s, u32 thread_index,
  86                  u32 session_index)
  87 {
  88   init_nat_k (kv, s->in2out.addr, s->in2out.port, s->in2out.fib_index,
  89               s->nat_proto);
  90   kv->value = (u64) thread_index << 32 | session_index;
  91 }
  92
  93 always_inline void
  94 init_nat_o2i_k (clib_bihash_kv_8_8_t *kv, snat_session_t *s)
  95 {
  96   return init_nat_k (kv, s->out2in.addr, s->out2in.port, s->out2in.fib_index,
  97                      s->nat_proto);
  98 }
  99
 100 always_inline void
 101 init_nat_o2i_kv (clib_bihash_kv_8_8_t *kv, snat_session_t *s, u32 thread_index,
 102                  u32 session_index)
 103 {
 104   init_nat_k (kv, s->out2in.addr, s->out2in.port, s->out2in.fib_index,
 105               s->nat_proto);
 106   kv->value = (u64) thread_index << 32 | session_index;
 107 }
 108
 109 always_inline u32
 110 nat_value_get_thread_index (clib_bihash_kv_8_8_t *value)
 111 {
 112   return value->value >> 32;
 113 }
 114
 115 always_inline u32
 116 nat_value_get_session_index (clib_bihash_kv_8_8_t *value)
 117 {
 118   return value->value & ~(u32) 0;
 119 }
 120
 121 always_inline void
 122 init_ed_k (clib_bihash_kv_16_8_t *kv, ip4_address_t l_addr, u16 l_port,
 123            ip4_address_t r_addr, u16 r_port, u32 fib_index, u8 proto)
 124 {
 125   kv->key[0] = (u64) r_addr.as_u32 << 32 | l_addr.as_u32;
 126   kv->key[1] =
 127     (u64) r_port << 48 | (u64) l_port << 32 | fib_index << 8 | proto;
 128 }
 129
 130 always_inline void
 131 init_ed_kv (clib_bihash_kv_16_8_t *kv, ip4_address_t l_addr, u16 l_port,
 132             ip4_address_t r_addr, u16 r_port, u32 fib_index, u8 proto,
 133             u32 thread_index, u32 session_index)
 134 {
 135   init_ed_k (kv, l_addr, l_port, r_addr, r_port, fib_index, proto);
 136   kv->value = (u64) thread_index << 32 | session_index;
 137 }
 138
 139 always_inline u32
 140 ed_value_get_thread_index (clib_bihash_kv_16_8_t *value)
 141 {
 142   return value->value >> 32;
 143 }
 144
 145 always_inline u32
 146 ed_value_get_session_index (clib_bihash_kv_16_8_t *value)
 147 {
 148   return value->value & ~(u32) 0;
 149 }
 150
 151 always_inline void
 152 split_ed_kv (clib_bihash_kv_16_8_t *kv, ip4_address_t *l_addr,
 153              ip4_address_t *r_addr, u8 *proto, u32 *fib_index, u16 *l_port,
 154              u16 *r_port)
 155 {
 156   if (l_addr)
 157     {
 158       l_addr->as_u32 = kv->key[0] & (u32) ~0;
 159     }
 160   if (r_addr)
 161     {
 162       r_addr->as_u32 = kv->key[0] >> 32;
 163     }
 164   if (r_port)
 165     {
 166       *r_port = kv->key[1] >> 48;
 167     }
 168   if (l_port)
 169     {
 170       *l_port = (kv->key[1] >> 32) & (u16) ~0;
 171     }
 172   if (fib_index)
 173     {
 174       *fib_index = (kv->key[1] >> 8) & ((1 << 24) - 1);
 175     }
 176   if (proto)
 177     {
 178       *proto = kv->key[1] & (u8) ~0;
 179     }
 180 }
 181
 182 static_always_inline int
 183 nat_get_icmp_session_lookup_values (vlib_buffer_t *b, ip4_header_t *ip0,
 184                                     ip4_address_t *lookup_saddr,
 185                                     u16 *lookup_sport,
 186                                     ip4_address_t *lookup_daddr,
 187                                     u16 *lookup_dport, u8 *lookup_protocol)
 188 {
 189   icmp46_header_t *icmp0;
 190   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 191   ip4_header_t *inner_ip0 = 0;
 192   void *l4_header = 0;
 193   icmp46_header_t *inner_icmp0;
 194
 195   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 196   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 197
 198   // avoid warning about unused variables in caller by setting to bogus values
 199   *lookup_sport = 0;
 200   *lookup_dport = 0;
 201
 202   if (!icmp_type_is_error_message (
 203         vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
 204     {
 205       *lookup_protocol = IP_PROTOCOL_ICMP;
 206       lookup_saddr->as_u32 = ip0->src_address.as_u32;
 207       *lookup_sport = vnet_buffer (b)->ip.reass.l4_src_port;
 208       lookup_daddr->as_u32 = ip0->dst_address.as_u32;
 209       *lookup_dport = vnet_buffer (b)->ip.reass.l4_dst_port;
 210     }
 211   else
 212     {
 213       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 214       l4_header = ip4_next_header (inner_ip0);
 215       *lookup_protocol = inner_ip0->protocol;
 216       lookup_saddr->as_u32 = inner_ip0->dst_address.as_u32;
 217       lookup_daddr->as_u32 = inner_ip0->src_address.as_u32;
 218       switch (ip_proto_to_nat_proto (inner_ip0->protocol))
 219         {
 220         case NAT_PROTOCOL_ICMP:
 221           inner_icmp0 = (icmp46_header_t *) l4_header;
 222           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 223           *lookup_sport = inner_echo0->identifier;
 224           *lookup_dport = inner_echo0->identifier;
 225           break;
 226         case NAT_PROTOCOL_UDP:
 227         case NAT_PROTOCOL_TCP:
 228           *lookup_sport = ((tcp_udp_header_t *) l4_header)->dst_port;
 229           *lookup_dport = ((tcp_udp_header_t *) l4_header)->src_port;
 230           break;
 231         default:
 232           return NAT_IN2OUT_ED_ERROR_UNSUPPORTED_PROTOCOL;
 233         }
 234     }
 235   return 0;
 236 }
 237
 238 always_inline u32
 239 nat44_session_get_timeout (snat_main_t *sm, snat_session_t *s)
 240 {
 241   switch (s->nat_proto)
 242     {
 243     case NAT_PROTOCOL_ICMP:
 244       return sm->timeouts.icmp;
 245     case NAT_PROTOCOL_UDP:
 246       return sm->timeouts.udp;
 247     case NAT_PROTOCOL_TCP:
 248       {
 249         if (s->state)
 250           return sm->timeouts.tcp.transitory;
 251         else
 252           return sm->timeouts.tcp.established;
 253       }
 254     default:
 255       return sm->timeouts.udp;
 256     }
 257
 258   return 0;
 259 }
 260
 261 static_always_inline u8
 262 nat44_ed_maximum_sessions_exceeded (snat_main_t *sm, u32 fib_index,
 263                                     u32 thread_index)
 264 {
 265   u32 translations;
 266   translations = pool_elts (sm->per_thread_data[thread_index].sessions);
 267   if (vec_len (sm->max_translations_per_fib) <= fib_index)
 268     fib_index = 0;
 269   return translations >= sm->max_translations_per_fib[fib_index];
 270 }
 271
 272 static_always_inline int
 273 nat_ed_lru_insert (snat_main_per_thread_data_t *tsm, snat_session_t *s,
 274                    f64 now, u8 proto)
 275 {
 276   dlist_elt_t *lru_list_elt;
 277   pool_get (tsm->lru_pool, lru_list_elt);
 278   s->lru_index = lru_list_elt - tsm->lru_pool;
 279   switch (proto)
 280     {
 281     case IP_PROTOCOL_UDP:
 282       s->lru_head_index = tsm->udp_lru_head_index;
 283       break;
 284     case IP_PROTOCOL_TCP:
 285       s->lru_head_index = tsm->tcp_trans_lru_head_index;
 286       break;
 287     case IP_PROTOCOL_ICMP:
 288       s->lru_head_index = tsm->icmp_lru_head_index;
 289       break;
 290     default:
 291       s->lru_head_index = tsm->unk_proto_lru_head_index;
 292       break;
 293     }
 294   clib_dlist_addtail (tsm->lru_pool, s->lru_head_index, s->lru_index);
 295   lru_list_elt->value = s - tsm->sessions;
 296   s->last_lru_update = now;
 297   return 1;
 298 }
 299
 300 static_always_inline void
 301 nat_6t_flow_to_ed_k (clib_bihash_kv_16_8_t *kv, nat_6t_flow_t *f)
 302 {
 303   init_ed_k (kv, f->match.saddr, f->match.sport, f->match.daddr,
 304              f->match.dport, f->match.fib_index, f->match.proto);
 305 }
 306
 307 static_always_inline void
 308 nat_6t_flow_to_ed_kv (clib_bihash_kv_16_8_t *kv, nat_6t_flow_t *f,
 309                       u32 thread_idx, u32 session_idx)
 310 {
 311   init_ed_kv (kv, f->match.saddr, f->match.sport, f->match.daddr,
 312               f->match.dport, f->match.fib_index, f->match.proto, thread_idx,
 313               session_idx);
 314 }
 315
 316 static_always_inline int
 317 nat_ed_ses_i2o_flow_hash_add_del (snat_main_t *sm, u32 thread_idx,
 318                                   snat_session_t *s, int is_add)
 319 {
 320   snat_main_per_thread_data_t *tsm =
 321     vec_elt_at_index (sm->per_thread_data, thread_idx);
 322   clib_bihash_kv_16_8_t kv;
 323   if (0 == is_add)
 324     {
 325       nat_6t_flow_to_ed_k (&kv, &s->i2o);
 326     }
 327   else
 328     {
 329       nat_6t_flow_to_ed_kv (&kv, &s->i2o, thread_idx, s - tsm->sessions);
 330       nat_6t_l3_l4_csum_calc (&s->i2o);
 331     }
 332   return clib_bihash_add_del_16_8 (&sm->flow_hash, &kv, is_add);
 333 }
 334
 335 static_always_inline int
 336 nat_ed_ses_o2i_flow_hash_add_del (snat_main_t *sm, u32 thread_idx,
 337                                   snat_session_t *s, int is_add)
 338 {
 339   snat_main_per_thread_data_t *tsm =
 340     vec_elt_at_index (sm->per_thread_data, thread_idx);
 341   clib_bihash_kv_16_8_t kv;
 342   if (0 == is_add)
 343     {
 344       nat_6t_flow_to_ed_k (&kv, &s->o2i);
 345     }
 346   else
 347     {
 348       nat_6t_flow_to_ed_kv (&kv, &s->o2i, thread_idx, s - tsm->sessions);
 349       nat_6t_l3_l4_csum_calc (&s->o2i);
 350     }
 351   return clib_bihash_add_del_16_8 (&sm->flow_hash, &kv, is_add);
 352 }
 353
 354 always_inline void
 355 nat_ed_session_delete (snat_main_t *sm, snat_session_t *ses, u32 thread_index,
 356                        int lru_delete
 357                        /* delete from global LRU list */)
 358 {
 359   snat_main_per_thread_data_t *tsm =
 360     vec_elt_at_index (sm->per_thread_data, thread_index);
 361
 362   if (lru_delete)
 363     {
 364       clib_dlist_remove (tsm->lru_pool, ses->lru_index);
 365     }
 366   pool_put_index (tsm->lru_pool, ses->lru_index);
 367   if (nat_ed_ses_i2o_flow_hash_add_del (sm, thread_index, ses, 0))
 368     nat_elog_warn (sm, "flow hash del failed");
 369   if (nat_ed_ses_o2i_flow_hash_add_del (sm, thread_index, ses, 0))
 370     nat_elog_warn (sm, "flow hash del failed");
 371   pool_put (tsm->sessions, ses);
 372   vlib_set_simple_counter (&sm->total_sessions, thread_index, 0,
 373                            pool_elts (tsm->sessions));
 374 }
 375
 376 static_always_inline int
 377 nat_lru_free_one_with_head (snat_main_t *sm, int thread_index, f64 now,
 378                             u32 head_index)
 379 {
 380   snat_session_t *s = NULL;
 381   dlist_elt_t *oldest_elt;
 382   f64 sess_timeout_time;
 383   u32 oldest_index;
 384   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 385   oldest_index = clib_dlist_remove_head (tsm->lru_pool, head_index);
 386   if (~0 != oldest_index)
 387     {
 388       oldest_elt = pool_elt_at_index (tsm->lru_pool, oldest_index);
 389       s = pool_elt_at_index (tsm->sessions, oldest_elt->value);
 390
 391       sess_timeout_time =
 392         s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 393       if (now >= sess_timeout_time ||
 394           (s->tcp_closed_timestamp && now >= s->tcp_closed_timestamp))
 395         {
 396           nat_free_session_data (sm, s, thread_index, 0);
 397           nat_ed_session_delete (sm, s, thread_index, 0);
 398           return 1;
 399         }
 400       else
 401         {
 402           clib_dlist_addhead (tsm->lru_pool, head_index, oldest_index);
 403         }
 404     }
 405   return 0;
 406 }
 407
 408 static_always_inline int
 409 nat_lru_free_one (snat_main_t *sm, int thread_index, f64 now)
 410 {
 411   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 412   int rc = 0;
 413 #define _(p)                                                                  \
 414   if ((rc = nat_lru_free_one_with_head (sm, thread_index, now,                \
 415                                         tsm->p##_lru_head_index)))            \
 416     {                                                                         \
 417       return rc;                                                              \
 418     }
 419   _ (tcp_trans);
 420   _ (udp);
 421   _ (unk_proto);
 422   _ (icmp);
 423   _ (tcp_estab);
 424 #undef _
 425   return 0;
 426 }
 427
 428 static_always_inline snat_session_t *
 429 nat_ed_session_alloc (snat_main_t *sm, u32 thread_index, f64 now, u8 proto)
 430 {
 431   snat_session_t *s;
 432   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 433
 434   nat_lru_free_one (sm, thread_index, now);
 435
 436   pool_get (tsm->sessions, s);
 437   clib_memset (s, 0, sizeof (*s));
 438
 439   nat_ed_lru_insert (tsm, s, now, proto);
 440
 441   s->ha_last_refreshed = now;
 442   vlib_set_simple_counter (&sm->total_sessions, thread_index, 0,
 443                            pool_elts (tsm->sessions));
 444   return s;
 445 }
 446
 447 // slow path
 448 static_always_inline void
 449 per_vrf_sessions_cleanup (u32 thread_index)
 450 {
 451   snat_main_t *sm = &snat_main;
 452   snat_main_per_thread_data_t *tsm =
 453     vec_elt_at_index (sm->per_thread_data, thread_index);
 454   per_vrf_sessions_t *per_vrf_sessions;
 455   u32 *to_free = 0, *i;
 456
 457   vec_foreach (per_vrf_sessions, tsm->per_vrf_sessions_vec)
 458     {
 459       if (per_vrf_sessions->expired)
 460         {
 461           if (per_vrf_sessions->ses_count == 0)
 462             {
 463               vec_add1 (to_free, per_vrf_sessions - tsm->per_vrf_sessions_vec);
 464             }
 465         }
 466     }
 467
 468   if (vec_len (to_free))
 469     {
 470       vec_foreach (i, to_free)
 471         {
 472           vec_del1 (tsm->per_vrf_sessions_vec, *i);
 473         }
 474     }
 475
 476   vec_free (to_free);
 477 }
 478
 479 // slow path
 480 static_always_inline void
 481 per_vrf_sessions_register_session (snat_session_t *s, u32 thread_index)
 482 {
 483   snat_main_t *sm = &snat_main;
 484   snat_main_per_thread_data_t *tsm =
 485     vec_elt_at_index (sm->per_thread_data, thread_index);
 486   per_vrf_sessions_t *per_vrf_sessions;
 487
 488   per_vrf_sessions_cleanup (thread_index);
 489
 490   // s->per_vrf_sessions_index == ~0 ... reuse of old session
 491
 492   vec_foreach (per_vrf_sessions, tsm->per_vrf_sessions_vec)
 493     {
 494       // ignore already expired registrations
 495       if (per_vrf_sessions->expired)
 496         continue;
 497
 498       if ((s->in2out.fib_index == per_vrf_sessions->rx_fib_index) &&
 499           (s->out2in.fib_index == per_vrf_sessions->tx_fib_index))
 500         {
 501           goto done;
 502         }
 503       if ((s->in2out.fib_index == per_vrf_sessions->tx_fib_index) &&
 504           (s->out2in.fib_index == per_vrf_sessions->rx_fib_index))
 505         {
 506           goto done;
 507         }
 508     }
 509
 510   // create a new registration
 511   vec_add2 (tsm->per_vrf_sessions_vec, per_vrf_sessions, 1);
 512   clib_memset (per_vrf_sessions, 0, sizeof (*per_vrf_sessions));
 513
 514   per_vrf_sessions->rx_fib_index = s->in2out.fib_index;
 515   per_vrf_sessions->tx_fib_index = s->out2in.fib_index;
 516
 517 done:
 518   s->per_vrf_sessions_index = per_vrf_sessions - tsm->per_vrf_sessions_vec;
 519   per_vrf_sessions->ses_count++;
 520 }
 521
 522 // fast path
 523 static_always_inline void
 524 per_vrf_sessions_unregister_session (snat_session_t *s, u32 thread_index)
 525 {
 526   snat_main_t *sm = &snat_main;
 527   snat_main_per_thread_data_t *tsm;
 528   per_vrf_sessions_t *per_vrf_sessions;
 529
 530   ASSERT (s->per_vrf_sessions_index != ~0);
 531
 532   tsm = vec_elt_at_index (sm->per_thread_data, thread_index);
 533   per_vrf_sessions =
 534     vec_elt_at_index (tsm->per_vrf_sessions_vec, s->per_vrf_sessions_index);
 535
 536   ASSERT (per_vrf_sessions->ses_count != 0);
 537
 538   per_vrf_sessions->ses_count--;
 539   s->per_vrf_sessions_index = ~0;
 540 }
 541
 542 // fast path
 543 static_always_inline u8
 544 per_vrf_sessions_is_expired (snat_session_t *s, u32 thread_index)
 545 {
 546   snat_main_t *sm = &snat_main;
 547   snat_main_per_thread_data_t *tsm;
 548   per_vrf_sessions_t *per_vrf_sessions;
 549
 550   ASSERT (s->per_vrf_sessions_index != ~0);
 551
 552   tsm = vec_elt_at_index (sm->per_thread_data, thread_index);
 553   per_vrf_sessions =
 554     vec_elt_at_index (tsm->per_vrf_sessions_vec, s->per_vrf_sessions_index);
 555   return per_vrf_sessions->expired;
 556 }
 557
 558 static_always_inline void
 559 nat_6t_flow_init (nat_6t_flow_t *f, u32 thread_idx, ip4_address_t saddr,
 560                   u16 sport, ip4_address_t daddr, u16 dport, u32 fib_index,
 561                   u8 proto, u32 session_idx)
 562 {
 563   clib_memset (f, 0, sizeof (*f));
 564   f->match.saddr = saddr;
 565   f->match.sport = sport;
 566   f->match.daddr = daddr;
 567   f->match.dport = dport;
 568   f->match.proto = proto;
 569   f->match.fib_index = fib_index;
 570 }
 571
 572 static_always_inline void
 573 nat_6t_i2o_flow_init (snat_main_t *sm, u32 thread_idx, snat_session_t *s,
 574                       ip4_address_t saddr, u16 sport, ip4_address_t daddr,
 575                       u16 dport, u32 fib_index, u8 proto)
 576 {
 577   snat_main_per_thread_data_t *tsm =
 578     vec_elt_at_index (sm->per_thread_data, thread_idx);
 579   nat_6t_flow_init (&s->i2o, thread_idx, saddr, sport, daddr, dport, fib_index,
 580                     proto, s - tsm->sessions);
 581 }
 582
 583 static_always_inline void
 584 nat_6t_o2i_flow_init (snat_main_t *sm, u32 thread_idx, snat_session_t *s,
 585                       ip4_address_t saddr, u16 sport, ip4_address_t daddr,
 586                       u16 dport, u32 fib_index, u8 proto)
 587 {
 588   snat_main_per_thread_data_t *tsm =
 589     vec_elt_at_index (sm->per_thread_data, thread_idx);
 590   nat_6t_flow_init (&s->o2i, thread_idx, saddr, sport, daddr, dport, fib_index,
 591                     proto, s - tsm->sessions);
 592 }
 593
 594 static_always_inline int
 595 nat_6t_t_eq (nat_6t_t *t1, nat_6t_t *t2)
 596 {
 597   return t1->as_u64[0] == t2->as_u64[0] && t1->as_u64[1] == t2->as_u64[1];
 598 }
 599
 600 static inline uword
 601 nat_pre_node_fn_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 602                         vlib_frame_t *frame, u32 def_next)
 603 {
 604   u32 n_left_from, *from;
 605
 606   from = vlib_frame_vector_args (frame);
 607   n_left_from = frame->n_vectors;
 608
 609   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 610   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 611   vlib_get_buffers (vm, from, b, n_left_from);
 612
 613   while (n_left_from >= 2)
 614     {
 615       u32 next0, next1;
 616       u32 arc_next0, arc_next1;
 617       vlib_buffer_t *b0, *b1;
 618
 619       b0 = *b;
 620       b++;
 621       b1 = *b;
 622       b++;
 623
 624       /* Prefetch next iteration. */
 625       if (PREDICT_TRUE (n_left_from >= 4))
 626         {
 627           vlib_buffer_t *p2, *p3;
 628
 629           p2 = *b;
 630           p3 = *(b + 1);
 631
 632           vlib_prefetch_buffer_header (p2, LOAD);
 633           vlib_prefetch_buffer_header (p3, LOAD);
 634
 635           CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
 636           CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, LOAD);
 637         }
 638
 639       next0 = def_next;
 640       next1 = def_next;
 641
 642       vnet_feature_next (&arc_next0, b0);
 643       vnet_feature_next (&arc_next1, b1);
 644
 645       vnet_buffer2 (b0)->nat.arc_next = arc_next0;
 646       vnet_buffer2 (b1)->nat.arc_next = arc_next1;
 647
 648       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
 649         {
 650           if (b0->flags & VLIB_BUFFER_IS_TRACED)
 651             {
 652               nat_pre_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
 653               t->next_index = next0;
 654               t->arc_next_index = arc_next0;
 655             }
 656           if (b1->flags & VLIB_BUFFER_IS_TRACED)
 657             {
 658               nat_pre_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
 659               t->next_index = next1;
 660               t->arc_next_index = arc_next1;
 661             }
 662         }
 663
 664       n_left_from -= 2;
 665       next[0] = next0;
 666       next[1] = next1;
 667       next += 2;
 668     }
 669
 670   while (n_left_from > 0)
 671     {
 672       u32 next0;
 673       u32 arc_next0;
 674       vlib_buffer_t *b0;
 675
 676       b0 = *b;
 677       b++;
 678
 679       next0 = def_next;
 680       vnet_feature_next (&arc_next0, b0);
 681       vnet_buffer2 (b0)->nat.arc_next = arc_next0;
 682
 683       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
 684                          (b0->flags & VLIB_BUFFER_IS_TRACED)))
 685         {
 686           nat_pre_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
 687           t->next_index = next0;
 688           t->arc_next_index = arc_next0;
 689         }
 690
 691       n_left_from--;
 692       next[0] = next0;
 693       next++;
 694     }
 695   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
 696                                frame->n_vectors);
 697
 698   return frame->n_vectors;
 699 }
 700
 701 static_always_inline u16
 702 snat_random_port (u16 min, u16 max)
 703 {
 704   snat_main_t *sm = &snat_main;
 705   u32 rwide;
 706   u16 r;
 707
 708   rwide = random_u32 (&sm->random_seed);
 709   r = rwide & 0xFFFF;
 710   if (r >= min && r <= max)
 711     return r;
 712
 713   return min + (rwide % (max - min + 1));
 714 }
 715
 716 always_inline u8
 717 is_interface_addr (snat_main_t *sm, vlib_node_runtime_t *node,
 718                    u32 sw_if_index0, u32 ip4_addr)
 719 {
 720   snat_runtime_t *rt = (snat_runtime_t *) node->runtime_data;
 721   ip4_address_t *first_int_addr;
 722
 723   if (PREDICT_FALSE (rt->cached_sw_if_index != sw_if_index0))
 724     {
 725       first_int_addr = ip4_interface_first_address (
 726         sm->ip4_main, sw_if_index0, 0 /* just want the address */);
 727       rt->cached_sw_if_index = sw_if_index0;
 728       if (first_int_addr)
 729         rt->cached_ip4_address = first_int_addr->as_u32;
 730       else
 731         rt->cached_ip4_address = 0;
 732     }
 733
 734   if (PREDICT_FALSE (ip4_addr == rt->cached_ip4_address))
 735     return 1;
 736   else
 737     return 0;
 738 }
 739
 740 always_inline void
 741 nat44_set_tcp_session_state_i2o (snat_main_t *sm, f64 now, snat_session_t *ses,
 742                                  vlib_buffer_t *b, u32 thread_index)
 743 {
 744   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 745   u8 tcp_flags = vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags;
 746   u32 tcp_ack_number = vnet_buffer (b)->ip.reass.tcp_ack_number;
 747   u32 tcp_seq_number = vnet_buffer (b)->ip.reass.tcp_seq_number;
 748   if ((ses->state == 0) && (tcp_flags & TCP_FLAG_RST))
 749     ses->state = NAT44_SES_RST;
 750   if ((ses->state == NAT44_SES_RST) && !(tcp_flags & TCP_FLAG_RST))
 751     ses->state = 0;
 752   if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_I2O_SYN) &&
 753       (ses->state & NAT44_SES_O2I_SYN))
 754     ses->state = 0;
 755   if (tcp_flags & TCP_FLAG_SYN)
 756     ses->state |= NAT44_SES_I2O_SYN;
 757   if (tcp_flags & TCP_FLAG_FIN)
 758     {
 759       ses->i2o_fin_seq = clib_net_to_host_u32 (tcp_seq_number);
 760       ses->state |= NAT44_SES_I2O_FIN;
 761     }
 762   if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_O2I_FIN))
 763     {
 764       if (clib_net_to_host_u32 (tcp_ack_number) > ses->o2i_fin_seq)
 765         {
 766           ses->state |= NAT44_SES_O2I_FIN_ACK;
 767           if (nat44_is_ses_closed (ses))
 768             { // if session is now closed, save the timestamp
 769               ses->tcp_closed_timestamp = now + sm->timeouts.tcp.transitory;
 770               ses->last_lru_update = now;
 771             }
 772         }
 773     }
 774
 775   // move the session to proper LRU
 776   if (ses->state)
 777     {
 778       ses->lru_head_index = tsm->tcp_trans_lru_head_index;
 779     }
 780   else
 781     {
 782       ses->lru_head_index = tsm->tcp_estab_lru_head_index;
 783     }
 784   clib_dlist_remove (tsm->lru_pool, ses->lru_index);
 785   clib_dlist_addtail (tsm->lru_pool, ses->lru_head_index, ses->lru_index);
 786 }
 787
 788 always_inline void
 789 nat44_set_tcp_session_state_o2i (snat_main_t *sm, f64 now, snat_session_t *ses,
 790                                  u8 tcp_flags, u32 tcp_ack_number,
 791                                  u32 tcp_seq_number, u32 thread_index)
 792 {
 793   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 794   if ((ses->state == 0) && (tcp_flags & TCP_FLAG_RST))
 795     ses->state = NAT44_SES_RST;
 796   if ((ses->state == NAT44_SES_RST) && !(tcp_flags & TCP_FLAG_RST))
 797     ses->state = 0;
 798   if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_I2O_SYN) &&
 799       (ses->state & NAT44_SES_O2I_SYN))
 800     ses->state = 0;
 801   if (tcp_flags & TCP_FLAG_SYN)
 802     ses->state |= NAT44_SES_O2I_SYN;
 803   if (tcp_flags & TCP_FLAG_FIN)
 804     {
 805       ses->o2i_fin_seq = clib_net_to_host_u32 (tcp_seq_number);
 806       ses->state |= NAT44_SES_O2I_FIN;
 807     }
 808   if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_I2O_FIN))
 809     {
 810       if (clib_net_to_host_u32 (tcp_ack_number) > ses->i2o_fin_seq)
 811         ses->state |= NAT44_SES_I2O_FIN_ACK;
 812       if (nat44_is_ses_closed (ses))
 813         { // if session is now closed, save the timestamp
 814           ses->tcp_closed_timestamp = now + sm->timeouts.tcp.transitory;
 815           ses->last_lru_update = now;
 816         }
 817     }
 818   // move the session to proper LRU
 819   if (ses->state)
 820     {
 821       ses->lru_head_index = tsm->tcp_trans_lru_head_index;
 822     }
 823   else
 824     {
 825       ses->lru_head_index = tsm->tcp_estab_lru_head_index;
 826     }
 827   clib_dlist_remove (tsm->lru_pool, ses->lru_index);
 828   clib_dlist_addtail (tsm->lru_pool, ses->lru_head_index, ses->lru_index);
 829 }
 830
 831 always_inline void
 832 nat44_session_update_counters (snat_session_t *s, f64 now, uword bytes,
 833                                u32 thread_index)
 834 {
 835   s->last_heard = now;
 836   s->total_pkts++;
 837   s->total_bytes += bytes;
 838 }
 839
 840 /** \brief Per-user LRU list maintenance */
 841 always_inline void
 842 nat44_session_update_lru (snat_main_t *sm, snat_session_t *s, u32 thread_index)
 843 {
 844   /* don't update too often - timeout is in magnitude of seconds anyway */
 845   if (s->last_heard > s->last_lru_update + 1)
 846     {
 847       clib_dlist_remove (sm->per_thread_data[thread_index].lru_pool,
 848                          s->lru_index);
 849       clib_dlist_addtail (sm->per_thread_data[thread_index].lru_pool,
 850                           s->lru_head_index, s->lru_index);
 851       s->last_lru_update = s->last_heard;
 852     }
 853 }
 854
 855 #endif /* __included_nat44_ed_inlines_h__ */
 856
 857 /*
 858  * fd.io coding-style-patch-verification: ON
 859  *
 860  * Local Variables:
 861  * eval: (c-set-style "gnu")
 862  * End:
 863  */