src/plugins/nat/out2in_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 outside to inside network translation
  18  */
  19
  20 #include <vlib/vlib.h>
  21 #include <vnet/vnet.h>
  22 #include <vnet/pg/pg.h>
  23 #include <vnet/ip/ip.h>
  24 #include <vnet/ethernet/ethernet.h>
  25 #include <vnet/fib/ip4_fib.h>
  26 #include <vnet/udp/udp.h>
  27 #include <vppinfra/error.h>
  28 #include <nat/nat.h>
  29 #include <nat/nat_ipfix_logging.h>
  30 #include <nat/nat_inlines.h>
  31 #include <nat/nat44/inlines.h>
  32 #include <nat/nat_syslog.h>
  33 #include <nat/nat_ha.h>
  34
  35 static char *nat_out2in_ed_error_strings[] = {
  36 #define _(sym,string) string,
  37   foreach_nat_out2in_ed_error
  38 #undef _
  39 };
  40
  41 typedef struct
  42 {
  43   u32 sw_if_index;
  44   u32 next_index;
  45   u32 session_index;
  46   u32 is_slow_path;
  47 } nat44_ed_out2in_trace_t;
  48
  49 static u8 *
  50 format_nat44_ed_out2in_trace (u8 * s, va_list * args)
  51 {
  52   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  53   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  54   nat44_ed_out2in_trace_t *t = va_arg (*args, nat44_ed_out2in_trace_t *);
  55   char *tag;
  56
  57   tag =
  58     t->is_slow_path ? "NAT44_OUT2IN_ED_SLOW_PATH" :
  59     "NAT44_OUT2IN_ED_FAST_PATH";
  60
  61   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  62               t->sw_if_index, t->next_index, t->session_index);
  63
  64   return s;
  65 }
  66
  67 static inline u32
  68 icmp_out2in_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
  69                           ip4_header_t * ip0, icmp46_header_t * icmp0,
  70                           u32 sw_if_index0, u32 rx_fib_index0,
  71                           vlib_node_runtime_t * node, u32 next0, f64 now,
  72                           u32 thread_index, snat_session_t ** p_s0)
  73 {
  74   next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
  75                        next0, thread_index, p_s0, 0);
  76   snat_session_t *s0 = *p_s0;
  77   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
  78     {
  79       /* Accounting */
  80       nat44_session_update_counters (s0, now,
  81                                      vlib_buffer_length_in_chain
  82                                      (sm->vlib_main, b0), thread_index);
  83       /* Per-user LRU list maintenance */
  84       nat44_session_update_lru (sm, s0, thread_index);
  85     }
  86   return next0;
  87 }
  88
  89 #ifndef CLIB_MARCH_VARIANT
  90 int
  91 nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  92 {
  93   snat_main_t *sm = &snat_main;
  94   nat44_is_idle_session_ctx_t *ctx = arg;
  95   snat_session_t *s;
  96   u64 sess_timeout_time;
  97   nat_ed_ses_key_t ed_key;
  98   clib_bihash_kv_16_8_t ed_kv;
  99   int i;
 100   snat_address_t *a;
 101   snat_session_key_t key;
 102   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 103                                                        ctx->thread_index);
 104
 105   s = pool_elt_at_index (tsm->sessions, kv->value);
 106   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 107   if (ctx->now >= sess_timeout_time)
 108     {
 109       ed_key.l_addr = s->in2out.addr;
 110       ed_key.r_addr = s->ext_host_addr;
 111       ed_key.fib_index = s->in2out.fib_index;
 112       if (snat_is_unk_proto_session (s))
 113         {
 114           ed_key.proto = s->in2out.port;
 115           ed_key.r_port = 0;
 116           ed_key.l_port = 0;
 117         }
 118       else
 119         {
 120           ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
 121           ed_key.l_port = s->in2out.port;
 122           ed_key.r_port = s->ext_host_port;
 123         }
 124       if (is_twice_nat_session (s))
 125         {
 126           ed_key.r_addr = s->ext_host_nat_addr;
 127           ed_key.r_port = s->ext_host_nat_port;
 128         }
 129       ed_kv.key[0] = ed_key.as_u64[0];
 130       ed_kv.key[1] = ed_key.as_u64[1];
 131       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &ed_kv, 0))
 132         nat_elog_warn ("in2out_ed key del failed");
 133
 134       ed_bihash_kv_t bihash_key;
 135       clib_memset (&bihash_key, 0, sizeof (bihash_key));
 136       bihash_key.k.dst_address = s->ext_host_addr.as_u32;
 137       bihash_key.k.dst_port = s->ext_host_port;
 138       bihash_key.k.src_address = s->out2in.addr.as_u32;
 139       bihash_key.k.src_port = s->out2in.port;
 140       bihash_key.k.protocol = s->out2in.protocol;
 141       clib_bihash_add_del_16_8 (&sm->ed_ext_ports, &bihash_key.kv,
 142                                 0 /* is_add */ );
 143
 144       if (snat_is_unk_proto_session (s))
 145         goto delete;
 146
 147       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 148                                            s->in2out.addr.as_u32,
 149                                            s->out2in.addr.as_u32,
 150                                            s->in2out.protocol,
 151                                            s->in2out.port,
 152                                            s->out2in.port,
 153                                            s->in2out.fib_index);
 154
 155       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 156                              &s->in2out.addr, s->in2out.port,
 157                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 158                              &s->out2in.addr, s->out2in.port,
 159                              &s->ext_host_addr, s->ext_host_port,
 160                              s->in2out.protocol, is_twice_nat_session (s));
 161
 162       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 163                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 164                    ctx->thread_index);
 165
 166       if (is_twice_nat_session (s))
 167         {
 168           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 169             {
 170               key.protocol = s->in2out.protocol;
 171               key.port = s->ext_host_nat_port;
 172               a = sm->twice_nat_addresses + i;
 173               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 174                 {
 175                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 176                                                       ctx->thread_index,
 177                                                       &key);
 178                   break;
 179                 }
 180             }
 181         }
 182
 183       if (snat_is_session_static (s))
 184         goto delete;
 185
 186       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 187                                           &s->out2in);
 188     delete:
 189       nat44_delete_session (sm, s, ctx->thread_index);
 190       return 1;
 191     }
 192
 193   return 0;
 194 }
 195 #endif
 196
 197 static snat_session_t *
 198 create_session_for_static_mapping_ed (snat_main_t * sm,
 199                                       vlib_buffer_t * b,
 200                                       snat_session_key_t l_key,
 201                                       snat_session_key_t e_key,
 202                                       vlib_node_runtime_t * node,
 203                                       u32 thread_index,
 204                                       twice_nat_type_t twice_nat,
 205                                       lb_nat_type_t lb_nat, f64 now)
 206 {
 207   snat_session_t *s;
 208   snat_user_t *u;
 209   ip4_header_t *ip;
 210   udp_header_t *udp;
 211   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 212   clib_bihash_kv_16_8_t kv;
 213   snat_session_key_t eh_key;
 214   nat44_is_idle_session_ctx_t ctx;
 215
 216   if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 217     {
 218       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 219       nat_elog_notice ("maximum sessions exceeded");
 220       return 0;
 221     }
 222
 223   u = nat_user_get_or_create (sm, &l_key.addr, l_key.fib_index, thread_index);
 224   if (!u)
 225     {
 226       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 227       nat_elog_warn ("create NAT user failed");
 228       return 0;
 229     }
 230
 231   s = nat_ed_session_alloc (sm, u, thread_index, now);
 232   if (!s)
 233     {
 234       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 235       nat44_delete_user_with_no_session (sm, u, thread_index);
 236       nat_elog_warn ("create NAT session failed");
 237       return 0;
 238     }
 239
 240   ip = vlib_buffer_get_current (b);
 241   udp = ip4_next_header (ip);
 242
 243   s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 244   s->ext_host_port = e_key.protocol == SNAT_PROTOCOL_ICMP ? 0 : udp->src_port;
 245   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 246   if (lb_nat)
 247     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 248   if (lb_nat == AFFINITY_LB_NAT)
 249     s->flags |= SNAT_SESSION_FLAG_AFFINITY;
 250   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 251   s->out2in = e_key;
 252   s->in2out = l_key;
 253   s->in2out.protocol = s->out2in.protocol;
 254   user_session_increment (sm, u, 1);
 255
 256   /* Add to lookup tables */
 257   make_ed_kv (&kv, &e_key.addr, &s->ext_host_addr, ip->protocol,
 258               e_key.fib_index, e_key.port, s->ext_host_port);
 259   kv.value = s - tsm->sessions;
 260   ctx.now = now;
 261   ctx.thread_index = thread_index;
 262   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, &kv,
 263                                                nat44_o2i_ed_is_idle_session_cb,
 264                                                &ctx))
 265     nat_elog_notice ("out2in-ed key add failed");
 266
 267   if (twice_nat == TWICE_NAT || (twice_nat == TWICE_NAT_SELF &&
 268                                  ip->src_address.as_u32 == l_key.addr.as_u32))
 269     {
 270       eh_key.protocol = e_key.protocol;
 271       if (snat_alloc_outside_address_and_port (sm->twice_nat_addresses, 0,
 272                                                thread_index, &eh_key,
 273                                                sm->port_per_thread,
 274                                                tsm->snat_thread_index))
 275         {
 276           b->error = node->errors[NAT_OUT2IN_ED_ERROR_OUT_OF_PORTS];
 277           nat44_delete_session (sm, s, thread_index);
 278           if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &kv, 0))
 279             nat_elog_notice ("out2in-ed key del failed");
 280           return 0;
 281         }
 282       s->ext_host_nat_addr.as_u32 = eh_key.addr.as_u32;
 283       s->ext_host_nat_port = eh_key.port;
 284       s->flags |= SNAT_SESSION_FLAG_TWICE_NAT;
 285       make_ed_kv (&kv, &l_key.addr, &s->ext_host_nat_addr, ip->protocol,
 286                   l_key.fib_index, l_key.port, s->ext_host_nat_port);
 287     }
 288   else
 289     {
 290       make_ed_kv (&kv, &l_key.addr, &s->ext_host_addr, ip->protocol,
 291                   l_key.fib_index, l_key.port, s->ext_host_port);
 292     }
 293   kv.value = s - tsm->sessions;
 294   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &kv,
 295                                                nat44_i2o_ed_is_idle_session_cb,
 296                                                &ctx))
 297     nat_elog_notice ("in2out-ed key add failed");
 298
 299   snat_ipfix_logging_nat44_ses_create (thread_index,
 300                                        s->in2out.addr.as_u32,
 301                                        s->out2in.addr.as_u32,
 302                                        s->in2out.protocol,
 303                                        s->in2out.port,
 304                                        s->out2in.port, s->in2out.fib_index);
 305
 306   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 307                          &s->in2out.addr, s->in2out.port,
 308                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 309                          &s->out2in.addr, s->out2in.port,
 310                          &s->ext_host_addr, s->ext_host_port,
 311                          s->in2out.protocol, is_twice_nat_session (s));
 312
 313   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 314                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 315                &s->ext_host_nat_addr, s->ext_host_nat_port,
 316                s->in2out.protocol, s->in2out.fib_index, s->flags,
 317                thread_index, 0);
 318
 319   return s;
 320 }
 321
 322 static int
 323 next_src_nat (snat_main_t * sm, ip4_header_t * ip, u8 proto, u16 src_port,
 324               u16 dst_port, u32 thread_index, u32 rx_fib_index)
 325 {
 326   clib_bihash_kv_16_8_t kv, value;
 327   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 328
 329   make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto,
 330               rx_fib_index, src_port, dst_port);
 331   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 332     return 1;
 333
 334   return 0;
 335 }
 336
 337 static void
 338 create_bypass_for_fwd (snat_main_t * sm, vlib_buffer_t * b, ip4_header_t * ip,
 339                        u32 rx_fib_index, u32 thread_index)
 340 {
 341   nat_ed_ses_key_t key;
 342   clib_bihash_kv_16_8_t kv, value;
 343   udp_header_t *udp;
 344   snat_user_t *u;
 345   snat_session_t *s = 0;
 346   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 347   f64 now = vlib_time_now (sm->vlib_main);
 348
 349   if (ip->protocol == IP_PROTOCOL_ICMP)
 350     {
 351       if (get_icmp_o2i_ed_key (b, ip, &key))
 352         return;
 353     }
 354   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 355     {
 356       udp = ip4_next_header (ip);
 357       key.r_addr = ip->src_address;
 358       key.l_addr = ip->dst_address;
 359       key.proto = ip->protocol;
 360       key.l_port = udp->dst_port;
 361       key.r_port = udp->src_port;
 362     }
 363   else
 364     {
 365       key.r_addr = ip->src_address;
 366       key.l_addr = ip->dst_address;
 367       key.proto = ip->protocol;
 368       key.l_port = key.r_port = 0;
 369     }
 370   key.fib_index = 0;
 371   kv.key[0] = key.as_u64[0];
 372   kv.key[1] = key.as_u64[1];
 373
 374   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 375     {
 376       s = pool_elt_at_index (tsm->sessions, value.value);
 377     }
 378   else
 379     {
 380       u32 proto;
 381
 382       if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 383         return;
 384
 385       u = nat_user_get_or_create (sm, &ip->dst_address, sm->inside_fib_index,
 386                                   thread_index);
 387       if (!u)
 388         {
 389           nat_elog_warn ("create NAT user failed");
 390           return;
 391         }
 392
 393       s = nat_ed_session_alloc (sm, u, thread_index, now);
 394       if (!s)
 395         {
 396           nat44_delete_user_with_no_session (sm, u, thread_index);
 397           nat_elog_warn ("create NAT session failed");
 398           return;
 399         }
 400
 401       proto = ip_proto_to_snat_proto (key.proto);
 402
 403       s->ext_host_addr = key.r_addr;
 404       s->ext_host_port = key.r_port;
 405       s->flags |= SNAT_SESSION_FLAG_FWD_BYPASS;
 406       s->out2in.addr = key.l_addr;
 407       s->out2in.port = key.l_port;
 408       s->out2in.protocol = proto;
 409       if (proto == ~0)
 410         {
 411           s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 412           s->out2in.port = ip->protocol;
 413         }
 414       s->out2in.fib_index = 0;
 415       s->in2out = s->out2in;
 416       user_session_increment (sm, u, 0);
 417
 418       kv.value = s - tsm->sessions;
 419       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &kv, 1))
 420         nat_elog_notice ("in2out_ed key add failed");
 421     }
 422
 423   if (ip->protocol == IP_PROTOCOL_TCP)
 424     {
 425       tcp_header_t *tcp = ip4_next_header (ip);
 426       if (nat44_set_tcp_session_state_o2i
 427           (sm, now, s, tcp->flags, tcp->ack_number, tcp->seq_number,
 428            thread_index))
 429         return;
 430     }
 431
 432   /* Accounting */
 433   nat44_session_update_counters (s, now, 0, thread_index);
 434   /* Per-user LRU list maintenance */
 435   nat44_session_update_lru (sm, s, thread_index);
 436 }
 437
 438 static inline void
 439 create_bypass_for_fwd_worker (snat_main_t * sm, vlib_buffer_t * b,
 440                               ip4_header_t * ip, u32 rx_fib_index)
 441 {
 442   ip4_header_t ip_wkr = {
 443     .src_address = ip->dst_address,
 444   };
 445   u32 thread_index = sm->worker_in2out_cb (&ip_wkr, rx_fib_index, 0);
 446
 447   create_bypass_for_fwd (sm, b, ip, rx_fib_index, thread_index);
 448 }
 449
 450 #ifndef CLIB_MARCH_VARIANT
 451 u32
 452 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 453                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 454                       u8 * p_proto, snat_session_key_t * p_value,
 455                       u8 * p_dont_translate, void *d, void *e)
 456 {
 457   u32 next = ~0, sw_if_index, rx_fib_index;
 458   nat_ed_ses_key_t key;
 459   clib_bihash_kv_16_8_t kv, value;
 460   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 461   snat_session_t *s = 0;
 462   u8 dont_translate = 0, is_addr_only, identity_nat;
 463   snat_session_key_t e_key, l_key;
 464
 465   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 466   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 467
 468   if (get_icmp_o2i_ed_key (b, ip, &key))
 469     {
 470       b->error = node->errors[NAT_OUT2IN_ED_ERROR_UNSUPPORTED_PROTOCOL];
 471       next = NAT_NEXT_DROP;
 472       goto out;
 473     }
 474   key.fib_index = rx_fib_index;
 475   kv.key[0] = key.as_u64[0];
 476   kv.key[1] = key.as_u64[1];
 477
 478   if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 479     {
 480       /* Try to match static mapping */
 481       e_key.addr = ip->dst_address;
 482       e_key.port = key.l_port;
 483       e_key.protocol = ip_proto_to_snat_proto (key.proto);
 484       e_key.fib_index = rx_fib_index;
 485       if (snat_static_mapping_match
 486           (sm, e_key, &l_key, 1, &is_addr_only, 0, 0, 0, &identity_nat))
 487         {
 488           if (!sm->forwarding_enabled)
 489             {
 490               /* Don't NAT packet aimed at the intfc address */
 491               if (PREDICT_FALSE (is_interface_addr (sm, node, sw_if_index,
 492                                                     ip->dst_address.as_u32)))
 493                 {
 494                   dont_translate = 1;
 495                   goto out;
 496                 }
 497               b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 498               next = NAT_NEXT_DROP;
 499               goto out;
 500             }
 501           else
 502             {
 503               dont_translate = 1;
 504               if (next_src_nat (sm, ip, key.proto, key.l_port, key.r_port,
 505                                 thread_index, rx_fib_index))
 506                 {
 507                   next = NAT_NEXT_IN2OUT_ED_FAST_PATH;
 508                   goto out;
 509                 }
 510               if (sm->num_workers > 1)
 511                 create_bypass_for_fwd_worker (sm, b, ip, rx_fib_index);
 512               else
 513                 create_bypass_for_fwd (sm, b, ip, rx_fib_index, thread_index);
 514               goto out;
 515             }
 516         }
 517
 518       if (PREDICT_FALSE
 519           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 520            ICMP4_echo_reply
 521            && (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 522                ICMP4_echo_request || !is_addr_only)))
 523         {
 524           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 525           next = NAT_NEXT_DROP;
 526           goto out;
 527         }
 528
 529       if (PREDICT_FALSE (identity_nat))
 530         {
 531           dont_translate = 1;
 532           goto out;
 533         }
 534
 535       /* Create session initiated by host from external network */
 536       s = create_session_for_static_mapping_ed (sm, b, l_key, e_key, node,
 537                                                 thread_index, 0, 0,
 538                                                 vlib_time_now
 539                                                 (sm->vlib_main));
 540
 541       if (!s)
 542         {
 543           next = NAT_NEXT_DROP;
 544           goto out;
 545         }
 546     }
 547   else
 548     {
 549       if (PREDICT_FALSE
 550           (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 551            ICMP4_echo_reply
 552            && vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags !=
 553            ICMP4_echo_request
 554            && !icmp_type_is_error_message (vnet_buffer (b)->ip.
 555                                            reass.icmp_type_or_tcp_flags)))
 556         {
 557           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 558           next = NAT_NEXT_DROP;
 559           goto out;
 560         }
 561
 562       s = pool_elt_at_index (tsm->sessions, value.value);
 563     }
 564
 565   *p_proto = ip_proto_to_snat_proto (key.proto);
 566 out:
 567   if (s)
 568     *p_value = s->in2out;
 569   *p_dont_translate = dont_translate;
 570   if (d)
 571     *(snat_session_t **) d = s;
 572   return next;
 573 }
 574 #endif
 575
 576 static snat_session_t *
 577 nat44_ed_out2in_unknown_proto (snat_main_t * sm,
 578                                vlib_buffer_t * b,
 579                                ip4_header_t * ip,
 580                                u32 rx_fib_index,
 581                                u32 thread_index,
 582                                f64 now,
 583                                vlib_main_t * vm, vlib_node_runtime_t * node)
 584 {
 585   clib_bihash_kv_8_8_t kv, value;
 586   clib_bihash_kv_16_8_t s_kv, s_value;
 587   snat_static_mapping_t *m;
 588   u32 old_addr, new_addr;
 589   ip_csum_t sum;
 590   snat_session_t *s;
 591   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 592   snat_user_t *u;
 593
 594   old_addr = ip->dst_address.as_u32;
 595
 596   make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
 597               rx_fib_index, 0, 0);
 598
 599   if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
 600     {
 601       s = pool_elt_at_index (tsm->sessions, s_value.value);
 602       new_addr = ip->dst_address.as_u32 = s->in2out.addr.as_u32;
 603     }
 604   else
 605     {
 606       if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 607         {
 608           b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 609           nat_elog_notice ("maximum sessions exceeded");
 610           return 0;
 611         }
 612
 613       make_sm_kv (&kv, &ip->dst_address, 0, 0, 0);
 614       if (clib_bihash_search_8_8
 615           (&sm->static_mapping_by_external, &kv, &value))
 616         {
 617           b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 618           return 0;
 619         }
 620
 621       m = pool_elt_at_index (sm->static_mappings, value.value);
 622
 623       new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 624
 625       u = nat_user_get_or_create (sm, &m->local_addr, m->fib_index,
 626                                   thread_index);
 627       if (!u)
 628         {
 629           b->error = node->errors[NAT_OUT2IN_ED_ERROR_CANNOT_CREATE_USER];
 630           nat_elog_warn ("create NAT user failed");
 631           return 0;
 632         }
 633
 634       /* Create a new session */
 635       s = nat_ed_session_alloc (sm, u, thread_index, now);
 636       if (!s)
 637         {
 638           b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_USER_SESS_EXCEEDED];
 639           nat44_delete_user_with_no_session (sm, u, thread_index);
 640           nat_elog_warn ("create NAT session failed");
 641           return 0;
 642         }
 643
 644       s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 645       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 646       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 647       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 648       s->out2in.addr.as_u32 = old_addr;
 649       s->out2in.fib_index = rx_fib_index;
 650       s->in2out.addr.as_u32 = new_addr;
 651       s->in2out.fib_index = m->fib_index;
 652       s->in2out.port = s->out2in.port = ip->protocol;
 653       user_session_increment (sm, u, 1);
 654
 655       /* Add to lookup tables */
 656       s_kv.value = s - tsm->sessions;
 657       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
 658         nat_elog_notice ("out2in key add failed");
 659
 660       make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
 661                   m->fib_index, 0, 0);
 662       s_kv.value = s - tsm->sessions;
 663       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 664         nat_elog_notice ("in2out key add failed");
 665     }
 666
 667   /* Update IP checksum */
 668   sum = ip->checksum;
 669   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 670   ip->checksum = ip_csum_fold (sum);
 671
 672   vnet_buffer (b)->sw_if_index[VLIB_TX] = s->in2out.fib_index;
 673
 674   /* Accounting */
 675   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 676                                  thread_index);
 677   /* Per-user LRU list maintenance */
 678   nat44_session_update_lru (sm, s, thread_index);
 679
 680   return s;
 681 }
 682
 683 static inline uword
 684 nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
 685                                           vlib_node_runtime_t * node,
 686                                           vlib_frame_t * frame)
 687 {
 688   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 689   nat_next_t next_index;
 690   snat_main_t *sm = &snat_main;
 691   f64 now = vlib_time_now (vm);
 692   u32 thread_index = vm->thread_index;
 693   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 694   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 695     0, fragments = 0;
 696
 697   stats_node_index = sm->ed_out2in_node_index;
 698
 699   from = vlib_frame_vector_args (frame);
 700   n_left_from = frame->n_vectors;
 701   next_index = node->cached_next_index;
 702
 703   while (n_left_from > 0)
 704     {
 705       u32 n_left_to_next;
 706
 707       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 708
 709       while (n_left_from > 0 && n_left_to_next > 0)
 710         {
 711           u32 bi0;
 712           vlib_buffer_t *b0;
 713           u32 next0, sw_if_index0, rx_fib_index0, proto0, old_addr0,
 714             new_addr0;
 715           u16 old_port0, new_port0;
 716           ip4_header_t *ip0;
 717           udp_header_t *udp0;
 718           tcp_header_t *tcp0;
 719           snat_session_t *s0 = 0;
 720           clib_bihash_kv_16_8_t kv0, value0;
 721           ip_csum_t sum0;
 722
 723           /* speculatively enqueue b0 to the current next frame */
 724           bi0 = from[0];
 725           to_next[0] = bi0;
 726           from += 1;
 727           to_next += 1;
 728           n_left_from -= 1;
 729           n_left_to_next -= 1;
 730
 731           b0 = vlib_get_buffer (vm, bi0);
 732           next0 = nat_buffer_opaque (b0)->arc_next;
 733
 734           vnet_buffer (b0)->snat.flags = 0;
 735           ip0 = vlib_buffer_get_current (b0);
 736
 737           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 738           rx_fib_index0 =
 739             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 740                                                  sw_if_index0);
 741
 742           if (PREDICT_FALSE (ip0->ttl == 1))
 743             {
 744               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 745               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 746                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 747                                            0);
 748               next0 = NAT_NEXT_ICMP_ERROR;
 749               goto trace0;
 750             }
 751
 752           udp0 = ip4_next_header (ip0);
 753           tcp0 = (tcp_header_t *) udp0;
 754           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 755
 756           if (PREDICT_FALSE (proto0 == ~0))
 757             {
 758               next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 759               goto trace0;
 760             }
 761
 762           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 763             {
 764               next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 765               goto trace0;
 766             }
 767
 768           make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
 769                       ip0->protocol, rx_fib_index0,
 770                       vnet_buffer (b0)->ip.reass.l4_dst_port,
 771                       vnet_buffer (b0)->ip.reass.l4_src_port);
 772
 773           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
 774             {
 775               next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 776               goto trace0;
 777             }
 778           s0 = pool_elt_at_index (tsm->sessions, value0.value);
 779
 780           if (s0->tcp_close_timestamp)
 781             {
 782               if (now >= s0->tcp_close_timestamp)
 783                 {
 784                   // session is closed, go slow path
 785                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 786                 }
 787               else
 788                 {
 789                   // session in transitory timeout, drop
 790                   b0->error = node->errors[NAT_OUT2IN_ED_ERROR_TCP_CLOSED];
 791                   next0 = NAT_NEXT_DROP;
 792                 }
 793               goto trace0;
 794             }
 795
 796           // drop if session expired
 797           u64 sess_timeout_time;
 798           sess_timeout_time = s0->last_heard +
 799             (f64) nat44_session_get_timeout (sm, s0);
 800           if (now >= sess_timeout_time)
 801             {
 802               // session is closed, go slow path
 803               nat_free_session_data (sm, s0, thread_index, 0);
 804               nat44_delete_session (sm, s0, thread_index);
 805               next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 806               goto trace0;
 807             }
 808           //
 809
 810           old_addr0 = ip0->dst_address.as_u32;
 811           new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
 812           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 813
 814           sum0 = ip0->checksum;
 815           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 816                                  dst_address);
 817           if (PREDICT_FALSE (is_twice_nat_session (s0)))
 818             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 819                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
 820                                    src_address);
 821           ip0->checksum = ip_csum_fold (sum0);
 822
 823           old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
 824
 825           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
 826             {
 827               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 828                 {
 829                   new_port0 = udp0->dst_port = s0->in2out.port;
 830                   sum0 = tcp0->checksum;
 831                   sum0 =
 832                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 833                                     dst_address);
 834                   sum0 =
 835                     ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 836                                     length);
 837                   if (is_twice_nat_session (s0))
 838                     {
 839                       sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 840                                              s0->ext_host_nat_addr.as_u32,
 841                                              ip4_header_t, dst_address);
 842                       sum0 =
 843                         ip_csum_update (sum0,
 844                                         vnet_buffer (b0)->ip.
 845                                         reass.l4_src_port,
 846                                         s0->ext_host_nat_port, ip4_header_t,
 847                                         length);
 848                       tcp0->src_port = s0->ext_host_nat_port;
 849                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 850                     }
 851                   tcp0->checksum = ip_csum_fold (sum0);
 852                 }
 853               tcp_packets++;
 854               if (nat44_set_tcp_session_state_o2i
 855                   (sm, now, s0,
 856                    vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags,
 857                    vnet_buffer (b0)->ip.reass.tcp_ack_number,
 858                    vnet_buffer (b0)->ip.reass.tcp_seq_number, thread_index))
 859                 goto trace0;
 860             }
 861           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
 862                    && udp0->checksum)
 863             {
 864               new_port0 = udp0->dst_port = s0->in2out.port;
 865               sum0 = udp0->checksum;
 866               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 867                                      dst_address);
 868               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 869                                      length);
 870               if (PREDICT_FALSE (is_twice_nat_session (s0)))
 871                 {
 872                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 873                                          s0->ext_host_nat_addr.as_u32,
 874                                          ip4_header_t, dst_address);
 875                   sum0 =
 876                     ip_csum_update (sum0,
 877                                     vnet_buffer (b0)->ip.reass.l4_src_port,
 878                                     s0->ext_host_nat_port, ip4_header_t,
 879                                     length);
 880                   udp0->src_port = s0->ext_host_nat_port;
 881                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 882                 }
 883               udp0->checksum = ip_csum_fold (sum0);
 884               udp_packets++;
 885             }
 886           else
 887             {
 888               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 889                 {
 890                   new_port0 = udp0->dst_port = s0->in2out.port;
 891                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
 892                     {
 893                       udp0->src_port = s0->ext_host_nat_port;
 894                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 895                     }
 896                 }
 897               udp_packets++;
 898             }
 899
 900           /* Accounting */
 901           nat44_session_update_counters (s0, now,
 902                                          vlib_buffer_length_in_chain (vm, b0),
 903                                          thread_index);
 904           /* Per-user LRU list maintenance */
 905           nat44_session_update_lru (sm, s0, thread_index);
 906
 907         trace0:
 908           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 909                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 910             {
 911               nat44_ed_out2in_trace_t *t =
 912                 vlib_add_trace (vm, node, b0, sizeof (*t));
 913               t->sw_if_index = sw_if_index0;
 914               t->next_index = next0;
 915               t->is_slow_path = 0;
 916
 917               if (s0)
 918                 t->session_index = s0 - tsm->sessions;
 919               else
 920                 t->session_index = ~0;
 921             }
 922
 923           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
 924           /* verify speculative enqueue, maybe switch current next frame */
 925           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 926                                            to_next, n_left_to_next,
 927                                            bi0, next0);
 928         }
 929
 930       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 931     }
 932
 933   vlib_node_increment_counter (vm, stats_node_index,
 934                                NAT_OUT2IN_ED_ERROR_OUT2IN_PACKETS,
 935                                pkts_processed);
 936   vlib_node_increment_counter (vm, stats_node_index,
 937                                NAT_OUT2IN_ED_ERROR_TCP_PACKETS, tcp_packets);
 938   vlib_node_increment_counter (vm, stats_node_index,
 939                                NAT_OUT2IN_ED_ERROR_UDP_PACKETS, udp_packets);
 940   vlib_node_increment_counter (vm, stats_node_index,
 941                                NAT_OUT2IN_ED_ERROR_ICMP_PACKETS,
 942                                icmp_packets);
 943   vlib_node_increment_counter (vm, stats_node_index,
 944                                NAT_OUT2IN_ED_ERROR_OTHER_PACKETS,
 945                                other_packets);
 946   vlib_node_increment_counter (vm, stats_node_index,
 947                                NAT_OUT2IN_ED_ERROR_FRAGMENTS, fragments);
 948   return frame->n_vectors;
 949 }
 950
 951 static inline uword
 952 nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 953                                           vlib_node_runtime_t * node,
 954                                           vlib_frame_t * frame)
 955 {
 956   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 957   nat_next_t next_index;
 958   snat_main_t *sm = &snat_main;
 959   f64 now = vlib_time_now (vm);
 960   u32 thread_index = vm->thread_index;
 961   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 962   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 963     0, fragments = 0;
 964
 965   stats_node_index = sm->ed_out2in_slowpath_node_index;
 966
 967   from = vlib_frame_vector_args (frame);
 968   n_left_from = frame->n_vectors;
 969   next_index = node->cached_next_index;
 970
 971   while (n_left_from > 0)
 972     {
 973       u32 n_left_to_next;
 974
 975       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 976
 977       while (n_left_from > 0 && n_left_to_next > 0)
 978         {
 979           u32 bi0;
 980           vlib_buffer_t *b0;
 981           u32 next0, sw_if_index0, rx_fib_index0, proto0, old_addr0,
 982             new_addr0;
 983           u16 old_port0, new_port0;
 984           ip4_header_t *ip0;
 985           udp_header_t *udp0;
 986           tcp_header_t *tcp0;
 987           icmp46_header_t *icmp0;
 988           snat_session_t *s0 = 0;
 989           clib_bihash_kv_16_8_t kv0, value0;
 990           ip_csum_t sum0;
 991           snat_session_key_t e_key0, l_key0;
 992           lb_nat_type_t lb_nat0;
 993           twice_nat_type_t twice_nat0;
 994           u8 identity_nat0;
 995
 996           /* speculatively enqueue b0 to the current next frame */
 997           bi0 = from[0];
 998           to_next[0] = bi0;
 999           from += 1;
1000           to_next += 1;
1001           n_left_from -= 1;
1002           n_left_to_next -= 1;
1003
1004           b0 = vlib_get_buffer (vm, bi0);
1005           next0 = nat_buffer_opaque (b0)->arc_next;
1006
1007           vnet_buffer (b0)->snat.flags = 0;
1008           ip0 = vlib_buffer_get_current (b0);
1009
1010           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1011           rx_fib_index0 =
1012             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1013                                                  sw_if_index0);
1014
1015           if (PREDICT_FALSE (ip0->ttl == 1))
1016             {
1017               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1018               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1019                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1020                                            0);
1021               next0 = NAT_NEXT_ICMP_ERROR;
1022               goto trace0;
1023             }
1024
1025           udp0 = ip4_next_header (ip0);
1026           tcp0 = (tcp_header_t *) udp0;
1027           icmp0 = (icmp46_header_t *) udp0;
1028           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1029
1030           if (PREDICT_FALSE (proto0 == ~0))
1031             {
1032               s0 =
1033                 nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
1034                                                thread_index, now, vm, node);
1035               if (!sm->forwarding_enabled)
1036                 {
1037                   if (!s0)
1038                     next0 = NAT_NEXT_DROP;
1039                 }
1040               other_packets++;
1041               goto trace0;
1042             }
1043
1044           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1045             {
1046               next0 = icmp_out2in_ed_slow_path
1047                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1048                  next0, now, thread_index, &s0);
1049               icmp_packets++;
1050               goto trace0;
1051             }
1052
1053           make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
1054                       ip0->protocol, rx_fib_index0,
1055                       vnet_buffer (b0)->ip.reass.l4_dst_port,
1056                       vnet_buffer (b0)->ip.reass.l4_src_port);
1057
1058           s0 = NULL;
1059           if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
1060             {
1061               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1062
1063               if (s0->tcp_close_timestamp && now >= s0->tcp_close_timestamp)
1064                 {
1065                   nat_free_session_data (sm, s0, thread_index, 0);
1066                   nat44_delete_session (sm, s0, thread_index);
1067                   s0 = NULL;
1068                 }
1069             }
1070
1071           if (!s0)
1072             {
1073               /* Try to match static mapping by external address and port,
1074                  destination address and port in packet */
1075               e_key0.addr = ip0->dst_address;
1076               e_key0.port = vnet_buffer (b0)->ip.reass.l4_dst_port;
1077               e_key0.protocol = proto0;
1078               e_key0.fib_index = rx_fib_index0;
1079
1080               if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
1081                                              &twice_nat0, &lb_nat0,
1082                                              &ip0->src_address,
1083                                              &identity_nat0))
1084                 {
1085                   /*
1086                    * Send DHCP packets to the ipv4 stack, or we won't
1087                    * be able to use dhcp client on the outside interface
1088                    */
1089                   if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1090                                      && (vnet_buffer (b0)->ip.
1091                                          reass.l4_dst_port ==
1092                                          clib_host_to_net_u16
1093                                          (UDP_DST_PORT_dhcp_to_client))))
1094                     {
1095                       goto trace0;
1096                     }
1097
1098                   if (!sm->forwarding_enabled)
1099                     {
1100                       b0->error =
1101                         node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1102                       next0 = NAT_NEXT_DROP;
1103                     }
1104                   else
1105                     {
1106                       if (next_src_nat (sm, ip0, ip0->protocol,
1107                                         vnet_buffer (b0)->ip.
1108                                         reass.l4_src_port,
1109                                         vnet_buffer (b0)->ip.
1110                                         reass.l4_dst_port, thread_index,
1111                                         rx_fib_index0))
1112                         {
1113                           next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
1114                           goto trace0;
1115                         }
1116                       if (sm->num_workers > 1)
1117                         create_bypass_for_fwd_worker (sm, b0, ip0,
1118                                                       rx_fib_index0);
1119                       else
1120                         create_bypass_for_fwd (sm, b0, ip0, rx_fib_index0,
1121                                                thread_index);
1122                     }
1123                   goto trace0;
1124                 }
1125
1126               if (PREDICT_FALSE (identity_nat0))
1127                 goto trace0;
1128
1129               if ((proto0 == SNAT_PROTOCOL_TCP)
1130                   && !tcp_flags_is_init (vnet_buffer (b0)->ip.
1131                                          reass.icmp_type_or_tcp_flags))
1132                 {
1133                   b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1134                   next0 = NAT_NEXT_DROP;
1135                   goto trace0;
1136                 }
1137
1138               /* Create session initiated by host from external network */
1139               s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
1140                                                          e_key0, node,
1141                                                          thread_index,
1142                                                          twice_nat0,
1143                                                          lb_nat0, now);
1144               if (!s0)
1145                 {
1146                   next0 = NAT_NEXT_DROP;
1147                   goto trace0;
1148                 }
1149             }
1150
1151           old_addr0 = ip0->dst_address.as_u32;
1152           new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
1153           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1154
1155           sum0 = ip0->checksum;
1156           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1157                                  dst_address);
1158           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1159             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1160                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
1161                                    src_address);
1162           ip0->checksum = ip_csum_fold (sum0);
1163
1164           old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
1165
1166           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1167             {
1168               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1169                 {
1170                   new_port0 = udp0->dst_port = s0->in2out.port;
1171                   sum0 = tcp0->checksum;
1172                   sum0 =
1173                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1174                                     dst_address);
1175                   sum0 =
1176                     ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1177                                     length);
1178                   if (is_twice_nat_session (s0))
1179                     {
1180                       sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1181                                              s0->ext_host_nat_addr.as_u32,
1182                                              ip4_header_t, dst_address);
1183                       sum0 =
1184                         ip_csum_update (sum0,
1185                                         vnet_buffer (b0)->ip.
1186                                         reass.l4_src_port,
1187                                         s0->ext_host_nat_port, ip4_header_t,
1188                                         length);
1189                       tcp0->src_port = s0->ext_host_nat_port;
1190                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1191                     }
1192                   tcp0->checksum = ip_csum_fold (sum0);
1193                 }
1194               tcp_packets++;
1195               if (nat44_set_tcp_session_state_o2i
1196                   (sm, now, s0,
1197                    vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags,
1198                    vnet_buffer (b0)->ip.reass.tcp_ack_number,
1199                    vnet_buffer (b0)->ip.reass.tcp_seq_number, thread_index))
1200                 goto trace0;
1201             }
1202           else if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment
1203                    && udp0->checksum)
1204             {
1205               new_port0 = udp0->dst_port = s0->in2out.port;
1206               sum0 = udp0->checksum;
1207               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1208                                      dst_address);
1209               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1210                                      length);
1211               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1212                 {
1213                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1214                                          s0->ext_host_nat_addr.as_u32,
1215                                          ip4_header_t, dst_address);
1216                   sum0 =
1217                     ip_csum_update (sum0,
1218                                     vnet_buffer (b0)->ip.reass.l4_src_port,
1219                                     s0->ext_host_nat_port, ip4_header_t,
1220                                     length);
1221                   udp0->src_port = s0->ext_host_nat_port;
1222                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1223                 }
1224               udp0->checksum = ip_csum_fold (sum0);
1225               udp_packets++;
1226             }
1227           else
1228             {
1229               if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1230                 {
1231                   new_port0 = udp0->dst_port = s0->in2out.port;
1232                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1233                     {
1234                       udp0->src_port = s0->ext_host_nat_port;
1235                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1236                     }
1237                 }
1238               udp_packets++;
1239             }
1240
1241           /* Accounting */
1242           nat44_session_update_counters (s0, now,
1243                                          vlib_buffer_length_in_chain (vm, b0),
1244                                          thread_index);
1245           /* Per-user LRU list maintenance */
1246           nat44_session_update_lru (sm, s0, thread_index);
1247
1248         trace0:
1249           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1250                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1251             {
1252               nat44_ed_out2in_trace_t *t =
1253                 vlib_add_trace (vm, node, b0, sizeof (*t));
1254               t->sw_if_index = sw_if_index0;
1255               t->next_index = next0;
1256               t->is_slow_path = 1;
1257
1258               if (s0)
1259                 t->session_index = s0 - tsm->sessions;
1260               else
1261                 t->session_index = ~0;
1262             }
1263
1264           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
1265           /* verify speculative enqueue, maybe switch current next frame */
1266           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1267                                            to_next, n_left_to_next,
1268                                            bi0, next0);
1269         }
1270
1271       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1272     }
1273
1274   vlib_node_increment_counter (vm, stats_node_index,
1275                                NAT_OUT2IN_ED_ERROR_OUT2IN_PACKETS,
1276                                pkts_processed);
1277   vlib_node_increment_counter (vm, stats_node_index,
1278                                NAT_OUT2IN_ED_ERROR_TCP_PACKETS, tcp_packets);
1279   vlib_node_increment_counter (vm, stats_node_index,
1280                                NAT_OUT2IN_ED_ERROR_UDP_PACKETS, udp_packets);
1281   vlib_node_increment_counter (vm, stats_node_index,
1282                                NAT_OUT2IN_ED_ERROR_ICMP_PACKETS,
1283                                icmp_packets);
1284   vlib_node_increment_counter (vm, stats_node_index,
1285                                NAT_OUT2IN_ED_ERROR_OTHER_PACKETS,
1286                                other_packets);
1287   vlib_node_increment_counter (vm, stats_node_index,
1288                                NAT_OUT2IN_ED_ERROR_FRAGMENTS, fragments);
1289   return frame->n_vectors;
1290 }
1291
1292 VLIB_NODE_FN (nat44_ed_out2in_node) (vlib_main_t * vm,
1293                                      vlib_node_runtime_t * node,
1294                                      vlib_frame_t * frame)
1295 {
1296   return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame);
1297 }
1298
1299 /* *INDENT-OFF* */
1300 VLIB_REGISTER_NODE (nat44_ed_out2in_node) = {
1301   .name = "nat44-ed-out2in",
1302   .vector_size = sizeof (u32),
1303   .sibling_of = "nat-default",
1304   .format_trace = format_nat44_ed_out2in_trace,
1305   .type = VLIB_NODE_TYPE_INTERNAL,
1306   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1307   .error_strings = nat_out2in_ed_error_strings,
1308   .runtime_data_bytes = sizeof (snat_runtime_t),
1309 };
1310 /* *INDENT-ON* */
1311
1312 VLIB_NODE_FN (nat44_ed_out2in_slowpath_node) (vlib_main_t * vm,
1313                                               vlib_node_runtime_t * node,
1314                                               vlib_frame_t * frame)
1315 {
1316   return nat44_ed_out2in_slow_path_node_fn_inline (vm, node, frame);
1317 }
1318
1319 /* *INDENT-OFF* */
1320 VLIB_REGISTER_NODE (nat44_ed_out2in_slowpath_node) = {
1321   .name = "nat44-ed-out2in-slowpath",
1322   .vector_size = sizeof (u32),
1323   .sibling_of = "nat-default",
1324   .format_trace = format_nat44_ed_out2in_trace,
1325   .type = VLIB_NODE_TYPE_INTERNAL,
1326   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1327   .error_strings = nat_out2in_ed_error_strings,
1328   .runtime_data_bytes = sizeof (snat_runtime_t),
1329 };
1330 /* *INDENT-ON* */
1331
1332 static u8 *
1333 format_nat_pre_trace (u8 * s, va_list * args)
1334 {
1335   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1336   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1337   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
1338   return format (s, "out2in next_index %d", t->next_index);
1339 }
1340
1341 VLIB_NODE_FN (nat_pre_out2in_node) (vlib_main_t * vm,
1342                                     vlib_node_runtime_t * node,
1343                                     vlib_frame_t * frame)
1344 {
1345   return nat_pre_node_fn_inline (vm, node, frame,
1346                                  NAT_NEXT_OUT2IN_ED_FAST_PATH);
1347 }
1348
1349 /* *INDENT-OFF* */
1350 VLIB_REGISTER_NODE (nat_pre_out2in_node) = {
1351   .name = "nat-pre-out2in",
1352   .vector_size = sizeof (u32),
1353   .sibling_of = "nat-default",
1354   .format_trace = format_nat_pre_trace,
1355   .type = VLIB_NODE_TYPE_INTERNAL,
1356   .n_errors = 0,
1357  };
1358 /* *INDENT-ON* */
1359
1360 /*
1361  * fd.io coding-style-patch-verification: ON
1362  *
1363  * Local Variables:
1364  * eval: (c-set-style "gnu")
1365  * End:
1366  */