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_reass.h>
  31 #include <nat/nat_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 enum
  42 {
  43   NAT44_ED_OUT2IN_NEXT_DROP,
  44   NAT44_ED_OUT2IN_NEXT_LOOKUP,
  45   NAT44_ED_OUT2IN_NEXT_ICMP_ERROR,
  46   NAT44_ED_OUT2IN_NEXT_IN2OUT,
  47   NAT44_ED_OUT2IN_NEXT_SLOW_PATH,
  48   NAT44_ED_OUT2IN_NEXT_REASS,
  49   NAT44_ED_OUT2IN_N_NEXT,
  50 } nat44_ed_out2in_next_t;
  51
  52 typedef struct
  53 {
  54   u32 sw_if_index;
  55   u32 next_index;
  56   u32 session_index;
  57   u32 is_slow_path;
  58 } nat44_ed_out2in_trace_t;
  59
  60 static u8 *
  61 format_nat44_ed_out2in_trace (u8 * s, va_list * args)
  62 {
  63   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  64   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  65   nat44_ed_out2in_trace_t *t = va_arg (*args, nat44_ed_out2in_trace_t *);
  66   char *tag;
  67
  68   tag =
  69     t->is_slow_path ? "NAT44_OUT2IN_ED_SLOW_PATH" :
  70     "NAT44_OUT2IN_ED_FAST_PATH";
  71
  72   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  73               t->sw_if_index, t->next_index, t->session_index);
  74
  75   return s;
  76 }
  77
  78 static inline u32
  79 icmp_out2in_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
  80                           ip4_header_t * ip0, icmp46_header_t * icmp0,
  81                           u32 sw_if_index0, u32 rx_fib_index0,
  82                           vlib_node_runtime_t * node, u32 next0, f64 now,
  83                           u32 thread_index, snat_session_t ** p_s0)
  84 {
  85   next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
  86                        next0, thread_index, p_s0, 0);
  87   snat_session_t *s0 = *p_s0;
  88   if (PREDICT_TRUE (next0 != NAT44_ED_OUT2IN_NEXT_DROP && s0))
  89     {
  90       /* Accounting */
  91       nat44_session_update_counters (s0, now,
  92                                      vlib_buffer_length_in_chain
  93                                      (sm->vlib_main, b0), thread_index);
  94       /* Per-user LRU list maintenance */
  95       nat44_session_update_lru (sm, s0, thread_index);
  96     }
  97   return next0;
  98 }
  99
 100 #ifndef CLIB_MARCH_VARIANT
 101 int
 102 nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
 103 {
 104   snat_main_t *sm = &snat_main;
 105   nat44_is_idle_session_ctx_t *ctx = arg;
 106   snat_session_t *s;
 107   u64 sess_timeout_time;
 108   nat_ed_ses_key_t ed_key;
 109   clib_bihash_kv_16_8_t ed_kv;
 110   int i;
 111   snat_address_t *a;
 112   snat_session_key_t key;
 113   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 114                                                        ctx->thread_index);
 115
 116   s = pool_elt_at_index (tsm->sessions, kv->value);
 117   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 118   if (ctx->now >= sess_timeout_time)
 119     {
 120       ed_key.l_addr = s->in2out.addr;
 121       ed_key.r_addr = s->ext_host_addr;
 122       ed_key.fib_index = s->in2out.fib_index;
 123       if (snat_is_unk_proto_session (s))
 124         {
 125           ed_key.proto = s->in2out.port;
 126           ed_key.r_port = 0;
 127           ed_key.l_port = 0;
 128         }
 129       else
 130         {
 131           ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
 132           ed_key.l_port = s->in2out.port;
 133           ed_key.r_port = s->ext_host_port;
 134         }
 135       if (is_twice_nat_session (s))
 136         {
 137           ed_key.r_addr = s->ext_host_nat_addr;
 138           ed_key.r_port = s->ext_host_nat_port;
 139         }
 140       ed_kv.key[0] = ed_key.as_u64[0];
 141       ed_kv.key[1] = ed_key.as_u64[1];
 142       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &ed_kv, 0))
 143         nat_elog_warn ("in2out_ed key del failed");
 144
 145       if (snat_is_unk_proto_session (s))
 146         goto delete;
 147
 148       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 149                                            s->in2out.addr.as_u32,
 150                                            s->out2in.addr.as_u32,
 151                                            s->in2out.protocol,
 152                                            s->in2out.port,
 153                                            s->out2in.port,
 154                                            s->in2out.fib_index);
 155
 156       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 157                              &s->in2out.addr, s->in2out.port,
 158                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 159                              &s->out2in.addr, s->out2in.port,
 160                              &s->ext_host_addr, s->ext_host_port,
 161                              s->in2out.protocol, is_twice_nat_session (s));
 162
 163       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 164                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 165                    ctx->thread_index);
 166
 167       if (is_twice_nat_session (s))
 168         {
 169           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 170             {
 171               key.protocol = s->in2out.protocol;
 172               key.port = s->ext_host_nat_port;
 173               a = sm->twice_nat_addresses + i;
 174               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 175                 {
 176                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 177                                                       ctx->thread_index,
 178                                                       &key);
 179                   break;
 180                 }
 181             }
 182         }
 183
 184       if (snat_is_session_static (s))
 185         goto delete;
 186
 187       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 188                                           &s->out2in);
 189     delete:
 190       nat44_delete_session (sm, s, ctx->thread_index);
 191       return 1;
 192     }
 193
 194   return 0;
 195 }
 196 #endif
 197
 198 static snat_session_t *
 199 create_session_for_static_mapping_ed (snat_main_t * sm,
 200                                       vlib_buffer_t * b,
 201                                       snat_session_key_t l_key,
 202                                       snat_session_key_t e_key,
 203                                       vlib_node_runtime_t * node,
 204                                       u32 thread_index,
 205                                       twice_nat_type_t twice_nat,
 206                                       lb_nat_type_t lb_nat, f64 now)
 207 {
 208   snat_session_t *s;
 209   snat_user_t *u;
 210   ip4_header_t *ip;
 211   udp_header_t *udp;
 212   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 213   clib_bihash_kv_16_8_t kv;
 214   snat_session_key_t eh_key;
 215   nat44_is_idle_session_ctx_t ctx;
 216
 217   if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 218     {
 219       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 220       nat_elog_notice ("maximum sessions exceeded");
 221       return 0;
 222     }
 223
 224   u = nat_user_get_or_create (sm, &l_key.addr, l_key.fib_index, thread_index);
 225   if (!u)
 226     {
 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       nat44_delete_user_with_no_session (sm, u, thread_index);
 235       nat_elog_warn ("create NAT session failed");
 236       return 0;
 237     }
 238
 239   ip = vlib_buffer_get_current (b);
 240   udp = ip4_next_header (ip);
 241
 242   s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 243   s->ext_host_port = e_key.protocol == SNAT_PROTOCOL_ICMP ? 0 : udp->src_port;
 244   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 245   if (lb_nat)
 246     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 247   if (lb_nat == AFFINITY_LB_NAT)
 248     s->flags |= SNAT_SESSION_FLAG_AFFINITY;
 249   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 250   s->out2in = e_key;
 251   s->in2out = l_key;
 252   s->in2out.protocol = s->out2in.protocol;
 253   user_session_increment (sm, u, 1);
 254
 255   /* Add to lookup tables */
 256   make_ed_kv (&kv, &e_key.addr, &s->ext_host_addr, ip->protocol,
 257               e_key.fib_index, e_key.port, s->ext_host_port);
 258   kv.value = s - tsm->sessions;
 259   ctx.now = now;
 260   ctx.thread_index = thread_index;
 261   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, &kv,
 262                                                nat44_o2i_ed_is_idle_session_cb,
 263                                                &ctx))
 264     nat_elog_notice ("out2in-ed key add failed");
 265
 266   if (twice_nat == TWICE_NAT || (twice_nat == TWICE_NAT_SELF &&
 267                                  ip->src_address.as_u32 == l_key.addr.as_u32))
 268     {
 269       eh_key.protocol = e_key.protocol;
 270       if (snat_alloc_outside_address_and_port (sm->twice_nat_addresses, 0,
 271                                                thread_index, &eh_key,
 272                                                sm->port_per_thread,
 273                                                tsm->snat_thread_index))
 274         {
 275           b->error = node->errors[NAT_OUT2IN_ED_ERROR_OUT_OF_PORTS];
 276           nat44_delete_session (sm, s, thread_index);
 277           if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &kv, 0))
 278             nat_elog_notice ("out2in-ed key del failed");
 279           return 0;
 280         }
 281       s->ext_host_nat_addr.as_u32 = eh_key.addr.as_u32;
 282       s->ext_host_nat_port = eh_key.port;
 283       s->flags |= SNAT_SESSION_FLAG_TWICE_NAT;
 284       make_ed_kv (&kv, &l_key.addr, &s->ext_host_nat_addr, ip->protocol,
 285                   l_key.fib_index, l_key.port, s->ext_host_nat_port);
 286     }
 287   else
 288     {
 289       make_ed_kv (&kv, &l_key.addr, &s->ext_host_addr, ip->protocol,
 290                   l_key.fib_index, l_key.port, s->ext_host_port);
 291     }
 292   kv.value = s - tsm->sessions;
 293   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &kv,
 294                                                nat44_i2o_ed_is_idle_session_cb,
 295                                                &ctx))
 296     nat_elog_notice ("in2out-ed key add failed");
 297
 298   snat_ipfix_logging_nat44_ses_create (thread_index,
 299                                        s->in2out.addr.as_u32,
 300                                        s->out2in.addr.as_u32,
 301                                        s->in2out.protocol,
 302                                        s->in2out.port,
 303                                        s->out2in.port, s->in2out.fib_index);
 304
 305   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 306                          &s->in2out.addr, s->in2out.port,
 307                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 308                          &s->out2in.addr, s->out2in.port,
 309                          &s->ext_host_addr, s->ext_host_port,
 310                          s->in2out.protocol, is_twice_nat_session (s));
 311
 312   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 313                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 314                &s->ext_host_nat_addr, s->ext_host_nat_port,
 315                s->in2out.protocol, s->in2out.fib_index, s->flags,
 316                thread_index, 0);
 317
 318   return s;
 319 }
 320
 321 static int
 322 next_src_nat (snat_main_t * sm, ip4_header_t * ip, u8 proto, u16 src_port,
 323               u16 dst_port, u32 thread_index, u32 rx_fib_index)
 324 {
 325   clib_bihash_kv_16_8_t kv, value;
 326   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 327
 328   make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto,
 329               rx_fib_index, src_port, dst_port);
 330   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 331     return 1;
 332
 333   return 0;
 334 }
 335
 336 static void
 337 create_bypass_for_fwd (snat_main_t * sm, ip4_header_t * ip, u32 rx_fib_index,
 338                        u32 thread_index)
 339 {
 340   nat_ed_ses_key_t key;
 341   clib_bihash_kv_16_8_t kv, value;
 342   udp_header_t *udp;
 343   snat_user_t *u;
 344   snat_session_t *s = 0;
 345   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 346   f64 now = vlib_time_now (sm->vlib_main);
 347
 348   if (ip->protocol == IP_PROTOCOL_ICMP)
 349     {
 350       if (get_icmp_o2i_ed_key (ip, &key))
 351         return;
 352     }
 353   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 354     {
 355       udp = ip4_next_header (ip);
 356       key.r_addr = ip->src_address;
 357       key.l_addr = ip->dst_address;
 358       key.proto = ip->protocol;
 359       key.l_port = udp->dst_port;
 360       key.r_port = udp->src_port;
 361     }
 362   else
 363     {
 364       key.r_addr = ip->src_address;
 365       key.l_addr = ip->dst_address;
 366       key.proto = ip->protocol;
 367       key.l_port = key.r_port = 0;
 368     }
 369   key.fib_index = 0;
 370   kv.key[0] = key.as_u64[0];
 371   kv.key[1] = key.as_u64[1];
 372
 373   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 374     {
 375       s = pool_elt_at_index (tsm->sessions, value.value);
 376     }
 377   else
 378     {
 379       u32 proto;
 380
 381       if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 382         return;
 383
 384       u = nat_user_get_or_create (sm, &ip->dst_address, sm->inside_fib_index,
 385                                   thread_index);
 386       if (!u)
 387         {
 388           nat_elog_warn ("create NAT user failed");
 389           return;
 390         }
 391
 392       s = nat_ed_session_alloc (sm, u, thread_index, now);
 393       if (!s)
 394         {
 395           nat44_delete_user_with_no_session (sm, u, thread_index);
 396           nat_elog_warn ("create NAT session failed");
 397           return;
 398         }
 399
 400       proto = ip_proto_to_snat_proto (key.proto);
 401
 402       s->ext_host_addr = key.r_addr;
 403       s->ext_host_port = key.r_port;
 404       s->flags |= SNAT_SESSION_FLAG_FWD_BYPASS;
 405       s->out2in.addr = key.l_addr;
 406       s->out2in.port = key.l_port;
 407       s->out2in.protocol = proto;
 408       if (proto == ~0)
 409         {
 410           s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 411           s->out2in.port = ip->protocol;
 412         }
 413       s->out2in.fib_index = 0;
 414       s->in2out = s->out2in;
 415       user_session_increment (sm, u, 0);
 416
 417       kv.value = s - tsm->sessions;
 418       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &kv, 1))
 419         nat_elog_notice ("in2out_ed key add failed");
 420     }
 421
 422   if (ip->protocol == IP_PROTOCOL_TCP)
 423     {
 424       tcp_header_t *tcp = ip4_next_header (ip);
 425       if (nat44_set_tcp_session_state_o2i (sm, s, tcp, thread_index))
 426         return;
 427     }
 428
 429   /* Accounting */
 430   nat44_session_update_counters (s, now, 0, thread_index);
 431   /* Per-user LRU list maintenance */
 432   nat44_session_update_lru (sm, s, thread_index);
 433 }
 434
 435 static inline void
 436 create_bypass_for_fwd_worker (snat_main_t * sm, ip4_header_t * ip,
 437                               u32 rx_fib_index)
 438 {
 439   ip4_header_t ip_wkr = {
 440     .src_address = ip->dst_address,
 441   };
 442   u32 thread_index = sm->worker_in2out_cb (&ip_wkr, rx_fib_index, 0);
 443
 444   create_bypass_for_fwd (sm, ip, rx_fib_index, thread_index);
 445 }
 446
 447 #ifndef CLIB_MARCH_VARIANT
 448 u32
 449 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 450                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 451                       u8 * p_proto, snat_session_key_t * p_value,
 452                       u8 * p_dont_translate, void *d, void *e)
 453 {
 454   u32 next = ~0, sw_if_index, rx_fib_index;
 455   icmp46_header_t *icmp;
 456   nat_ed_ses_key_t key;
 457   clib_bihash_kv_16_8_t kv, value;
 458   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 459   snat_session_t *s = 0;
 460   u8 dont_translate = 0, is_addr_only, identity_nat;
 461   snat_session_key_t e_key, l_key;
 462
 463   icmp = (icmp46_header_t *) ip4_next_header (ip);
 464   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 465   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 466
 467   if (get_icmp_o2i_ed_key (ip, &key))
 468     {
 469       b->error = node->errors[NAT_OUT2IN_ED_ERROR_UNSUPPORTED_PROTOCOL];
 470       next = NAT44_ED_OUT2IN_NEXT_DROP;
 471       goto out;
 472     }
 473   key.fib_index = rx_fib_index;
 474   kv.key[0] = key.as_u64[0];
 475   kv.key[1] = key.as_u64[1];
 476
 477   if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 478     {
 479       /* Try to match static mapping */
 480       e_key.addr = ip->dst_address;
 481       e_key.port = key.l_port;
 482       e_key.protocol = ip_proto_to_snat_proto (key.proto);
 483       e_key.fib_index = rx_fib_index;
 484       if (snat_static_mapping_match
 485           (sm, e_key, &l_key, 1, &is_addr_only, 0, 0, 0, &identity_nat))
 486         {
 487           if (!sm->forwarding_enabled)
 488             {
 489               /* Don't NAT packet aimed at the intfc address */
 490               if (PREDICT_FALSE (is_interface_addr (sm, node, sw_if_index,
 491                                                     ip->dst_address.as_u32)))
 492                 {
 493                   dont_translate = 1;
 494                   goto out;
 495                 }
 496               b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 497               next = NAT44_ED_OUT2IN_NEXT_DROP;
 498               goto out;
 499             }
 500           else
 501             {
 502               dont_translate = 1;
 503               if (next_src_nat (sm, ip, key.proto, key.l_port, key.r_port,
 504                                 thread_index, rx_fib_index))
 505                 {
 506                   next = NAT44_ED_OUT2IN_NEXT_IN2OUT;
 507                   goto out;
 508                 }
 509               if (sm->num_workers > 1)
 510                 create_bypass_for_fwd_worker (sm, ip, rx_fib_index);
 511               else
 512                 create_bypass_for_fwd (sm, ip, rx_fib_index, thread_index);
 513               goto out;
 514             }
 515         }
 516
 517       if (PREDICT_FALSE (icmp->type != ICMP4_echo_reply &&
 518                          (icmp->type != ICMP4_echo_request || !is_addr_only)))
 519         {
 520           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 521           next = NAT44_ED_OUT2IN_NEXT_DROP;
 522           goto out;
 523         }
 524
 525       if (PREDICT_FALSE (identity_nat))
 526         {
 527           dont_translate = 1;
 528           goto out;
 529         }
 530
 531       /* Create session initiated by host from external network */
 532       s = create_session_for_static_mapping_ed (sm, b, l_key, e_key, node,
 533                                                 thread_index, 0, 0,
 534                                                 vlib_time_now
 535                                                 (sm->vlib_main));
 536
 537       if (!s)
 538         {
 539           next = NAT44_ED_OUT2IN_NEXT_DROP;
 540           goto out;
 541         }
 542     }
 543   else
 544     {
 545       if (PREDICT_FALSE (icmp->type != ICMP4_echo_reply &&
 546                          icmp->type != ICMP4_echo_request &&
 547                          !icmp_is_error_message (icmp)))
 548         {
 549           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 550           next = NAT44_ED_OUT2IN_NEXT_DROP;
 551           goto out;
 552         }
 553
 554       s = pool_elt_at_index (tsm->sessions, value.value);
 555     }
 556
 557   *p_proto = ip_proto_to_snat_proto (key.proto);
 558 out:
 559   if (s)
 560     *p_value = s->in2out;
 561   *p_dont_translate = dont_translate;
 562   if (d)
 563     *(snat_session_t **) d = s;
 564   return next;
 565 }
 566 #endif
 567
 568 static snat_session_t *
 569 nat44_ed_out2in_unknown_proto (snat_main_t * sm,
 570                                vlib_buffer_t * b,
 571                                ip4_header_t * ip,
 572                                u32 rx_fib_index,
 573                                u32 thread_index,
 574                                f64 now,
 575                                vlib_main_t * vm, vlib_node_runtime_t * node)
 576 {
 577   clib_bihash_kv_8_8_t kv, value;
 578   clib_bihash_kv_16_8_t s_kv, s_value;
 579   snat_static_mapping_t *m;
 580   u32 old_addr, new_addr;
 581   ip_csum_t sum;
 582   snat_session_t *s;
 583   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 584   snat_user_t *u;
 585
 586   old_addr = ip->dst_address.as_u32;
 587
 588   make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
 589               rx_fib_index, 0, 0);
 590
 591   if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
 592     {
 593       s = pool_elt_at_index (tsm->sessions, s_value.value);
 594       new_addr = ip->dst_address.as_u32 = s->in2out.addr.as_u32;
 595     }
 596   else
 597     {
 598       if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 599         {
 600           b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 601           nat_elog_notice ("maximum sessions exceeded");
 602           return 0;
 603         }
 604
 605       make_sm_kv (&kv, &ip->dst_address, 0, 0, 0);
 606       if (clib_bihash_search_8_8
 607           (&sm->static_mapping_by_external, &kv, &value))
 608         {
 609           b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 610           return 0;
 611         }
 612
 613       m = pool_elt_at_index (sm->static_mappings, value.value);
 614
 615       new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 616
 617       u = nat_user_get_or_create (sm, &m->local_addr, m->fib_index,
 618                                   thread_index);
 619       if (!u)
 620         {
 621           nat_elog_warn ("create NAT user failed");
 622           return 0;
 623         }
 624
 625       /* Create a new session */
 626       s = nat_ed_session_alloc (sm, u, thread_index, now);
 627       if (!s)
 628         {
 629           nat44_delete_user_with_no_session (sm, u, thread_index);
 630           nat_elog_warn ("create NAT session failed");
 631           return 0;
 632         }
 633
 634       s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 635       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 636       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 637       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 638       s->out2in.addr.as_u32 = old_addr;
 639       s->out2in.fib_index = rx_fib_index;
 640       s->in2out.addr.as_u32 = new_addr;
 641       s->in2out.fib_index = m->fib_index;
 642       s->in2out.port = s->out2in.port = ip->protocol;
 643       user_session_increment (sm, u, 1);
 644
 645       /* Add to lookup tables */
 646       s_kv.value = s - tsm->sessions;
 647       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
 648         nat_elog_notice ("out2in key add failed");
 649
 650       make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
 651                   m->fib_index, 0, 0);
 652       s_kv.value = s - tsm->sessions;
 653       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 654         nat_elog_notice ("in2out key add failed");
 655     }
 656
 657   /* Update IP checksum */
 658   sum = ip->checksum;
 659   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 660   ip->checksum = ip_csum_fold (sum);
 661
 662   vnet_buffer (b)->sw_if_index[VLIB_TX] = s->in2out.fib_index;
 663
 664   /* Accounting */
 665   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 666                                  thread_index);
 667   /* Per-user LRU list maintenance */
 668   nat44_session_update_lru (sm, s, thread_index);
 669
 670   return s;
 671 }
 672
 673 static inline uword
 674 nat44_ed_out2in_node_fn_inline (vlib_main_t * vm,
 675                                 vlib_node_runtime_t * node,
 676                                 vlib_frame_t * frame, int is_slow_path)
 677 {
 678   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 679   nat44_ed_out2in_next_t next_index;
 680   snat_main_t *sm = &snat_main;
 681   f64 now = vlib_time_now (vm);
 682   u32 thread_index = vm->thread_index;
 683   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 684   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 685     0, fragments = 0;
 686
 687   stats_node_index = is_slow_path ? sm->ed_out2in_slowpath_node_index :
 688     sm->ed_out2in_node_index;
 689
 690   from = vlib_frame_vector_args (frame);
 691   n_left_from = frame->n_vectors;
 692   next_index = node->cached_next_index;
 693
 694   while (n_left_from > 0)
 695     {
 696       u32 n_left_to_next;
 697
 698       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 699
 700       while (n_left_from >= 4 && n_left_to_next >= 2)
 701         {
 702           u32 bi0, bi1;
 703           vlib_buffer_t *b0, *b1;
 704           u32 next0, sw_if_index0, rx_fib_index0, proto0, old_addr0,
 705             new_addr0;
 706           u32 next1, sw_if_index1, rx_fib_index1, proto1, old_addr1,
 707             new_addr1;
 708           u16 old_port0, new_port0, old_port1, new_port1;
 709           ip4_header_t *ip0, *ip1;
 710           udp_header_t *udp0, *udp1;
 711           tcp_header_t *tcp0, *tcp1;
 712           icmp46_header_t *icmp0, *icmp1;
 713           snat_session_t *s0 = 0, *s1 = 0;
 714           clib_bihash_kv_16_8_t kv0, value0, kv1, value1;
 715           ip_csum_t sum0, sum1;
 716           snat_session_key_t e_key0, l_key0, e_key1, l_key1;
 717           lb_nat_type_t lb_nat0, lb_nat1;
 718           twice_nat_type_t twice_nat0, twice_nat1;
 719           u8 identity_nat0, identity_nat1;
 720
 721           /* Prefetch next iteration. */
 722           {
 723             vlib_buffer_t *p2, *p3;
 724
 725             p2 = vlib_get_buffer (vm, from[2]);
 726             p3 = vlib_get_buffer (vm, from[3]);
 727
 728             vlib_prefetch_buffer_header (p2, LOAD);
 729             vlib_prefetch_buffer_header (p3, LOAD);
 730
 731             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 732             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 733           }
 734
 735           /* speculatively enqueue b0 and b1 to the current next frame */
 736           to_next[0] = bi0 = from[0];
 737           to_next[1] = bi1 = from[1];
 738           from += 2;
 739           to_next += 2;
 740           n_left_from -= 2;
 741           n_left_to_next -= 2;
 742
 743           b0 = vlib_get_buffer (vm, bi0);
 744           b1 = vlib_get_buffer (vm, bi1);
 745
 746           next0 = NAT44_ED_OUT2IN_NEXT_LOOKUP;
 747           vnet_buffer (b0)->snat.flags = 0;
 748           ip0 = vlib_buffer_get_current (b0);
 749
 750           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 751           rx_fib_index0 =
 752             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 753                                                  sw_if_index0);
 754
 755           if (PREDICT_FALSE (ip0->ttl == 1))
 756             {
 757               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 758               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 759                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 760                                            0);
 761               next0 = NAT44_ED_OUT2IN_NEXT_ICMP_ERROR;
 762               goto trace00;
 763             }
 764
 765           udp0 = ip4_next_header (ip0);
 766           tcp0 = (tcp_header_t *) udp0;
 767           icmp0 = (icmp46_header_t *) udp0;
 768           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 769
 770           if (is_slow_path)
 771             {
 772               if (PREDICT_FALSE (proto0 == ~0))
 773                 {
 774                   s0 =
 775                     nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
 776                                                    thread_index, now, vm,
 777                                                    node);
 778                   other_packets++;
 779                   if (!sm->forwarding_enabled)
 780                     {
 781                       if (!s0)
 782                         next0 = NAT44_ED_OUT2IN_NEXT_DROP;
 783                       goto trace00;
 784                     }
 785                 }
 786
 787               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 788                 {
 789                   next0 = icmp_out2in_ed_slow_path
 790                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 791                      next0, now, thread_index, &s0);
 792                   icmp_packets++;
 793                   goto trace00;
 794                 }
 795             }
 796           else
 797             {
 798               if (PREDICT_FALSE (proto0 == ~0))
 799                 {
 800                   next0 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
 801                   goto trace00;
 802                 }
 803
 804               if (ip4_is_fragment (ip0))
 805                 {
 806                   next0 = NAT44_ED_OUT2IN_NEXT_REASS;
 807                   fragments++;
 808                   goto trace00;
 809                 }
 810
 811               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 812                 {
 813                   next0 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
 814                   goto trace00;
 815                 }
 816             }
 817
 818           make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
 819                       ip0->protocol, rx_fib_index0, udp0->dst_port,
 820                       udp0->src_port);
 821
 822           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
 823             {
 824               if (is_slow_path)
 825                 {
 826                   /* Try to match static mapping by external address and port,
 827                      destination address and port in packet */
 828                   e_key0.addr = ip0->dst_address;
 829                   e_key0.port = udp0->dst_port;
 830                   e_key0.protocol = proto0;
 831                   e_key0.fib_index = rx_fib_index0;
 832                   if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
 833                                                  &twice_nat0, &lb_nat0,
 834                                                  &ip0->src_address,
 835                                                  &identity_nat0))
 836                     {
 837                       /*
 838                        * Send DHCP packets to the ipv4 stack, or we won't
 839                        * be able to use dhcp client on the outside interface
 840                        */
 841                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
 842                                          && (udp0->dst_port ==
 843                                              clib_host_to_net_u16
 844                                              (UDP_DST_PORT_dhcp_to_client))))
 845                         {
 846                           vnet_feature_next (&next0, b0);
 847                           goto trace00;
 848                         }
 849
 850                       if (!sm->forwarding_enabled)
 851                         {
 852                           b0->error =
 853                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 854                           next0 = NAT44_ED_OUT2IN_NEXT_DROP;
 855                         }
 856                       else
 857                         {
 858                           if (next_src_nat (sm, ip0, ip0->protocol,
 859                                             udp0->src_port, udp0->dst_port,
 860                                             thread_index, rx_fib_index0))
 861                             {
 862                               next0 = NAT44_ED_OUT2IN_NEXT_IN2OUT;
 863                               goto trace00;
 864                             }
 865                           if (sm->num_workers > 1)
 866                             create_bypass_for_fwd_worker (sm, ip0,
 867                                                           rx_fib_index0);
 868                           else
 869                             create_bypass_for_fwd (sm, ip0, rx_fib_index0,
 870                                                    thread_index);
 871                         }
 872                       goto trace00;
 873                     }
 874
 875                   if (PREDICT_FALSE (identity_nat0))
 876                     goto trace00;
 877
 878                   if ((proto0 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp0))
 879                     {
 880                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
 881                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
 882                       goto trace00;
 883                     }
 884
 885                   /* Create session initiated by host from external network */
 886                   s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
 887                                                              e_key0, node,
 888                                                              thread_index,
 889                                                              twice_nat0,
 890                                                              lb_nat0, now);
 891
 892                   if (!s0)
 893                     {
 894                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
 895                       goto trace00;
 896                     }
 897                 }
 898               else
 899                 {
 900                   next0 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
 901                   goto trace00;
 902                 }
 903             }
 904           else
 905             {
 906               s0 = pool_elt_at_index (tsm->sessions, value0.value);
 907             }
 908
 909           old_addr0 = ip0->dst_address.as_u32;
 910           new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
 911           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 912
 913           sum0 = ip0->checksum;
 914           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 915                                  dst_address);
 916           if (PREDICT_FALSE (is_twice_nat_session (s0)))
 917             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 918                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
 919                                    src_address);
 920           ip0->checksum = ip_csum_fold (sum0);
 921
 922           old_port0 = udp0->dst_port;
 923           new_port0 = udp0->dst_port = s0->in2out.port;
 924
 925           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
 926             {
 927               sum0 = tcp0->checksum;
 928               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 929                                      dst_address);
 930               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 931                                      length);
 932               if (is_twice_nat_session (s0))
 933                 {
 934                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 935                                          s0->ext_host_nat_addr.as_u32,
 936                                          ip4_header_t, dst_address);
 937                   sum0 = ip_csum_update (sum0, tcp0->src_port,
 938                                          s0->ext_host_nat_port, ip4_header_t,
 939                                          length);
 940                   tcp0->src_port = s0->ext_host_nat_port;
 941                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 942                 }
 943               tcp0->checksum = ip_csum_fold (sum0);
 944               tcp_packets++;
 945               if (nat44_set_tcp_session_state_o2i
 946                   (sm, s0, tcp0, thread_index))
 947                 goto trace00;
 948             }
 949           else if (udp0->checksum)
 950             {
 951               sum0 = udp0->checksum;
 952               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 953                                      dst_address);
 954               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 955                                      length);
 956               if (PREDICT_FALSE (is_twice_nat_session (s0)))
 957                 {
 958                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 959                                          s0->ext_host_nat_addr.as_u32,
 960                                          ip4_header_t, dst_address);
 961                   sum0 = ip_csum_update (sum0, udp0->src_port,
 962                                          s0->ext_host_nat_port, ip4_header_t,
 963                                          length);
 964                   udp0->src_port = s0->ext_host_nat_port;
 965                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 966                 }
 967               udp0->checksum = ip_csum_fold (sum0);
 968               udp_packets++;
 969             }
 970           else
 971             {
 972               if (PREDICT_FALSE (is_twice_nat_session (s0)))
 973                 {
 974                   udp0->src_port = s0->ext_host_nat_port;
 975                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 976                 }
 977               udp_packets++;
 978             }
 979
 980           /* Accounting */
 981           nat44_session_update_counters (s0, now,
 982                                          vlib_buffer_length_in_chain (vm, b0),
 983                                          thread_index);
 984           /* Per-user LRU list maintenance */
 985           nat44_session_update_lru (sm, s0, thread_index);
 986
 987         trace00:
 988           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 989                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 990             {
 991               nat44_ed_out2in_trace_t *t =
 992                 vlib_add_trace (vm, node, b0, sizeof (*t));
 993               t->is_slow_path = is_slow_path;
 994               t->sw_if_index = sw_if_index0;
 995               t->next_index = next0;
 996               t->session_index = ~0;
 997               if (s0)
 998                 t->session_index = s0 - tsm->sessions;
 999             }
1000
1001           pkts_processed += next0 == NAT44_ED_OUT2IN_NEXT_LOOKUP;
1002
1003           next1 = NAT44_ED_OUT2IN_NEXT_LOOKUP;
1004           vnet_buffer (b1)->snat.flags = 0;
1005           ip1 = vlib_buffer_get_current (b1);
1006
1007           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1008           rx_fib_index1 =
1009             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1010                                                  sw_if_index1);
1011
1012           if (PREDICT_FALSE (ip1->ttl == 1))
1013             {
1014               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1015               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1016                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1017                                            0);
1018               next1 = NAT44_ED_OUT2IN_NEXT_ICMP_ERROR;
1019               goto trace01;
1020             }
1021
1022           udp1 = ip4_next_header (ip1);
1023           tcp1 = (tcp_header_t *) udp1;
1024           icmp1 = (icmp46_header_t *) udp1;
1025           proto1 = ip_proto_to_snat_proto (ip1->protocol);
1026
1027           if (is_slow_path)
1028             {
1029               if (PREDICT_FALSE (proto1 == ~0))
1030                 {
1031                   s1 =
1032                     nat44_ed_out2in_unknown_proto (sm, b1, ip1, rx_fib_index1,
1033                                                    thread_index, now, vm,
1034                                                    node);
1035                   other_packets++;
1036                   if (!sm->forwarding_enabled)
1037                     {
1038                       if (!s1)
1039                         next1 = NAT44_ED_OUT2IN_NEXT_DROP;
1040                       goto trace01;
1041                     }
1042                 }
1043
1044               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1045                 {
1046                   next1 = icmp_out2in_ed_slow_path
1047                     (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1048                      next1, now, thread_index, &s1);
1049                   icmp_packets++;
1050                   goto trace01;
1051                 }
1052             }
1053           else
1054             {
1055               if (PREDICT_FALSE (proto1 == ~0))
1056                 {
1057                   next1 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
1058                   goto trace01;
1059                 }
1060
1061               if (ip4_is_fragment (ip1))
1062                 {
1063                   next1 = NAT44_ED_OUT2IN_NEXT_REASS;
1064                   fragments++;
1065                   goto trace01;
1066                 }
1067
1068               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1069                 {
1070                   next1 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
1071                   goto trace01;
1072                 }
1073             }
1074
1075           make_ed_kv (&kv1, &ip1->dst_address, &ip1->src_address,
1076                       ip1->protocol, rx_fib_index1, udp1->dst_port,
1077                       udp1->src_port);
1078
1079           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv1, &value1))
1080             {
1081               if (is_slow_path)
1082                 {
1083                   /* Try to match static mapping by external address and port,
1084                      destination address and port in packet */
1085                   e_key1.addr = ip1->dst_address;
1086                   e_key1.port = udp1->dst_port;
1087                   e_key1.protocol = proto1;
1088                   e_key1.fib_index = rx_fib_index1;
1089                   if (snat_static_mapping_match (sm, e_key1, &l_key1, 1, 0,
1090                                                  &twice_nat1, &lb_nat1,
1091                                                  &ip1->src_address,
1092                                                  &identity_nat1))
1093                     {
1094                       /*
1095                        * Send DHCP packets to the ipv4 stack, or we won't
1096                        * be able to use dhcp client on the outside interface
1097                        */
1098                       if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_UDP
1099                                          && (udp1->dst_port ==
1100                                              clib_host_to_net_u16
1101                                              (UDP_DST_PORT_dhcp_to_client))))
1102                         {
1103                           vnet_feature_next (&next1, b1);
1104                           goto trace01;
1105                         }
1106
1107                       if (!sm->forwarding_enabled)
1108                         {
1109                           b1->error =
1110                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1111                           next1 = NAT44_ED_OUT2IN_NEXT_DROP;
1112                         }
1113                       else
1114                         {
1115                           if (next_src_nat (sm, ip1, ip1->protocol,
1116                                             udp1->src_port, udp1->dst_port,
1117                                             thread_index, rx_fib_index1))
1118                             {
1119                               next1 = NAT44_ED_OUT2IN_NEXT_IN2OUT;
1120                               goto trace01;
1121                             }
1122                           if (sm->num_workers > 1)
1123                             create_bypass_for_fwd_worker (sm, ip1,
1124                                                           rx_fib_index1);
1125                           else
1126                             create_bypass_for_fwd (sm, ip1, rx_fib_index1,
1127                                                    thread_index);
1128                         }
1129                       goto trace01;
1130                     }
1131
1132                   if (PREDICT_FALSE (identity_nat1))
1133                     goto trace01;
1134
1135                   if ((proto1 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp1))
1136                     {
1137                       b1->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1138                       next1 = NAT44_ED_OUT2IN_NEXT_DROP;
1139                       goto trace01;
1140                     }
1141
1142                   /* Create session initiated by host from external network */
1143                   s1 = create_session_for_static_mapping_ed (sm, b1, l_key1,
1144                                                              e_key1, node,
1145                                                              thread_index,
1146                                                              twice_nat1,
1147                                                              lb_nat1, now);
1148
1149                   if (!s1)
1150                     {
1151                       next1 = NAT44_ED_OUT2IN_NEXT_DROP;
1152                       goto trace01;
1153                     }
1154                 }
1155               else
1156                 {
1157                   next1 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
1158                   goto trace01;
1159                 }
1160             }
1161           else
1162             {
1163               s1 = pool_elt_at_index (tsm->sessions, value1.value);
1164             }
1165
1166           old_addr1 = ip1->dst_address.as_u32;
1167           new_addr1 = ip1->dst_address.as_u32 = s1->in2out.addr.as_u32;
1168           vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->in2out.fib_index;
1169
1170           sum1 = ip1->checksum;
1171           sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1172                                  dst_address);
1173           if (PREDICT_FALSE (is_twice_nat_session (s1)))
1174             sum1 = ip_csum_update (sum1, ip1->src_address.as_u32,
1175                                    s1->ext_host_nat_addr.as_u32, ip4_header_t,
1176                                    src_address);
1177           ip1->checksum = ip_csum_fold (sum1);
1178
1179           old_port1 = udp1->dst_port;
1180           new_port1 = udp1->dst_port = s1->in2out.port;
1181
1182           if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1183             {
1184               sum1 = tcp1->checksum;
1185               sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1186                                      dst_address);
1187               sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t,
1188                                      length);
1189               if (is_twice_nat_session (s1))
1190                 {
1191                   sum1 = ip_csum_update (sum1, ip1->src_address.as_u32,
1192                                          s1->ext_host_nat_addr.as_u32,
1193                                          ip4_header_t, dst_address);
1194                   sum1 = ip_csum_update (sum1, tcp1->src_port,
1195                                          s1->ext_host_nat_port, ip4_header_t,
1196                                          length);
1197                   tcp1->src_port = s1->ext_host_nat_port;
1198                   ip1->src_address.as_u32 = s1->ext_host_nat_addr.as_u32;
1199                 }
1200               tcp1->checksum = ip_csum_fold (sum1);
1201               tcp_packets++;
1202               if (nat44_set_tcp_session_state_o2i
1203                   (sm, s1, tcp1, thread_index))
1204                 goto trace01;
1205             }
1206           else if (udp1->checksum)
1207             {
1208               sum1 = udp1->checksum;
1209               sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1210                                      dst_address);
1211               sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t,
1212                                      length);
1213               if (PREDICT_FALSE (is_twice_nat_session (s1)))
1214                 {
1215                   sum1 = ip_csum_update (sum1, ip1->src_address.as_u32,
1216                                          s1->ext_host_nat_addr.as_u32,
1217                                          ip4_header_t, dst_address);
1218                   sum1 = ip_csum_update (sum1, udp1->src_port,
1219                                          s1->ext_host_nat_port, ip4_header_t,
1220                                          length);
1221                   udp1->src_port = s1->ext_host_nat_port;
1222                   ip1->src_address.as_u32 = s1->ext_host_nat_addr.as_u32;
1223                 }
1224               udp1->checksum = ip_csum_fold (sum1);
1225               udp_packets++;
1226             }
1227           else
1228             {
1229               if (PREDICT_FALSE (is_twice_nat_session (s1)))
1230                 {
1231                   udp1->src_port = s1->ext_host_nat_port;
1232                   ip1->src_address.as_u32 = s1->ext_host_nat_addr.as_u32;
1233                 }
1234               udp_packets++;
1235             }
1236
1237           /* Accounting */
1238           nat44_session_update_counters (s1, now,
1239                                          vlib_buffer_length_in_chain (vm, b1),
1240                                          thread_index);
1241           /* Per-user LRU list maintenance */
1242           nat44_session_update_lru (sm, s1, thread_index);
1243
1244         trace01:
1245           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1246                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1247             {
1248               nat44_ed_out2in_trace_t *t =
1249                 vlib_add_trace (vm, node, b1, sizeof (*t));
1250               t->is_slow_path = is_slow_path;
1251               t->sw_if_index = sw_if_index1;
1252               t->next_index = next1;
1253               t->session_index = ~0;
1254               if (s1)
1255                 t->session_index = s1 - tsm->sessions;
1256             }
1257
1258           pkts_processed += next1 == NAT44_ED_OUT2IN_NEXT_LOOKUP;
1259
1260           /* verify speculative enqueues, maybe switch current next frame */
1261           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1262                                            to_next, n_left_to_next,
1263                                            bi0, bi1, next0, next1);
1264         }
1265
1266       while (n_left_from > 0 && n_left_to_next > 0)
1267         {
1268           u32 bi0;
1269           vlib_buffer_t *b0;
1270           u32 next0, sw_if_index0, rx_fib_index0, proto0, old_addr0,
1271             new_addr0;
1272           u16 old_port0, new_port0;
1273           ip4_header_t *ip0;
1274           udp_header_t *udp0;
1275           tcp_header_t *tcp0;
1276           icmp46_header_t *icmp0;
1277           snat_session_t *s0 = 0;
1278           clib_bihash_kv_16_8_t kv0, value0;
1279           ip_csum_t sum0;
1280           snat_session_key_t e_key0, l_key0;
1281           lb_nat_type_t lb_nat0;
1282           twice_nat_type_t twice_nat0;
1283           u8 identity_nat0;
1284
1285           /* speculatively enqueue b0 to the current next frame */
1286           bi0 = from[0];
1287           to_next[0] = bi0;
1288           from += 1;
1289           to_next += 1;
1290           n_left_from -= 1;
1291           n_left_to_next -= 1;
1292
1293           b0 = vlib_get_buffer (vm, bi0);
1294           next0 = NAT44_ED_OUT2IN_NEXT_LOOKUP;
1295           vnet_buffer (b0)->snat.flags = 0;
1296           ip0 = vlib_buffer_get_current (b0);
1297
1298           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1299           rx_fib_index0 =
1300             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1301                                                  sw_if_index0);
1302
1303           if (PREDICT_FALSE (ip0->ttl == 1))
1304             {
1305               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1306               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1307                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1308                                            0);
1309               next0 = NAT44_ED_OUT2IN_NEXT_ICMP_ERROR;
1310               goto trace0;
1311             }
1312
1313           udp0 = ip4_next_header (ip0);
1314           tcp0 = (tcp_header_t *) udp0;
1315           icmp0 = (icmp46_header_t *) udp0;
1316           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1317
1318           if (is_slow_path)
1319             {
1320               if (PREDICT_FALSE (proto0 == ~0))
1321                 {
1322                   s0 =
1323                     nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
1324                                                    thread_index, now, vm,
1325                                                    node);
1326                   other_packets++;
1327                   if (!sm->forwarding_enabled)
1328                     {
1329                       if (!s0)
1330                         next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1331                       goto trace0;
1332                     }
1333                 }
1334
1335               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1336                 {
1337                   next0 = icmp_out2in_ed_slow_path
1338                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1339                      next0, now, thread_index, &s0);
1340                   icmp_packets++;
1341                   goto trace0;
1342                 }
1343             }
1344           else
1345             {
1346               if (PREDICT_FALSE (proto0 == ~0))
1347                 {
1348                   next0 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
1349                   goto trace0;
1350                 }
1351
1352               if (ip4_is_fragment (ip0))
1353                 {
1354                   next0 = NAT44_ED_OUT2IN_NEXT_REASS;
1355                   fragments++;
1356                   goto trace0;
1357                 }
1358
1359               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1360                 {
1361                   next0 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
1362                   goto trace0;
1363                 }
1364             }
1365
1366           make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
1367                       ip0->protocol, rx_fib_index0, udp0->dst_port,
1368                       udp0->src_port);
1369
1370           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
1371             {
1372               if (is_slow_path)
1373                 {
1374                   /* Try to match static mapping by external address and port,
1375                      destination address and port in packet */
1376                   e_key0.addr = ip0->dst_address;
1377                   e_key0.port = udp0->dst_port;
1378                   e_key0.protocol = proto0;
1379                   e_key0.fib_index = rx_fib_index0;
1380                   if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
1381                                                  &twice_nat0, &lb_nat0,
1382                                                  &ip0->src_address,
1383                                                  &identity_nat0))
1384                     {
1385                       /*
1386                        * Send DHCP packets to the ipv4 stack, or we won't
1387                        * be able to use dhcp client on the outside interface
1388                        */
1389                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1390                                          && (udp0->dst_port ==
1391                                              clib_host_to_net_u16
1392                                              (UDP_DST_PORT_dhcp_to_client))))
1393                         {
1394                           vnet_feature_next (&next0, b0);
1395                           goto trace0;
1396                         }
1397
1398                       if (!sm->forwarding_enabled)
1399                         {
1400                           b0->error =
1401                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1402                           next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1403                         }
1404                       else
1405                         {
1406                           if (next_src_nat (sm, ip0, ip0->protocol,
1407                                             udp0->src_port, udp0->dst_port,
1408                                             thread_index, rx_fib_index0))
1409                             {
1410                               next0 = NAT44_ED_OUT2IN_NEXT_IN2OUT;
1411                               goto trace0;
1412                             }
1413                           if (sm->num_workers > 1)
1414                             create_bypass_for_fwd_worker (sm, ip0,
1415                                                           rx_fib_index0);
1416                           else
1417                             create_bypass_for_fwd (sm, ip0, rx_fib_index0,
1418                                                    thread_index);
1419                         }
1420                       goto trace0;
1421                     }
1422
1423                   if (PREDICT_FALSE (identity_nat0))
1424                     goto trace0;
1425
1426                   if ((proto0 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp0))
1427                     {
1428                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1429                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1430                       goto trace0;
1431                     }
1432
1433                   /* Create session initiated by host from external network */
1434                   s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
1435                                                              e_key0, node,
1436                                                              thread_index,
1437                                                              twice_nat0,
1438                                                              lb_nat0, now);
1439
1440                   if (!s0)
1441                     {
1442                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1443                       goto trace0;
1444                     }
1445                 }
1446               else
1447                 {
1448                   next0 = NAT44_ED_OUT2IN_NEXT_SLOW_PATH;
1449                   goto trace0;
1450                 }
1451             }
1452           else
1453             {
1454               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1455             }
1456
1457           old_addr0 = ip0->dst_address.as_u32;
1458           new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
1459           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1460
1461           sum0 = ip0->checksum;
1462           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1463                                  dst_address);
1464           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1465             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1466                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
1467                                    src_address);
1468           ip0->checksum = ip_csum_fold (sum0);
1469
1470           old_port0 = udp0->dst_port;
1471           new_port0 = udp0->dst_port = s0->in2out.port;
1472
1473           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1474             {
1475               sum0 = tcp0->checksum;
1476               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1477                                      dst_address);
1478               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1479                                      length);
1480               if (is_twice_nat_session (s0))
1481                 {
1482                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1483                                          s0->ext_host_nat_addr.as_u32,
1484                                          ip4_header_t, dst_address);
1485                   sum0 = ip_csum_update (sum0, tcp0->src_port,
1486                                          s0->ext_host_nat_port, ip4_header_t,
1487                                          length);
1488                   tcp0->src_port = s0->ext_host_nat_port;
1489                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1490                 }
1491               tcp0->checksum = ip_csum_fold (sum0);
1492               tcp_packets++;
1493               if (nat44_set_tcp_session_state_o2i
1494                   (sm, s0, tcp0, thread_index))
1495                 goto trace0;
1496             }
1497           else if (udp0->checksum)
1498             {
1499               sum0 = udp0->checksum;
1500               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1501                                      dst_address);
1502               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1503                                      length);
1504               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1505                 {
1506                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1507                                          s0->ext_host_nat_addr.as_u32,
1508                                          ip4_header_t, dst_address);
1509                   sum0 = ip_csum_update (sum0, udp0->src_port,
1510                                          s0->ext_host_nat_port, ip4_header_t,
1511                                          length);
1512                   udp0->src_port = s0->ext_host_nat_port;
1513                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1514                 }
1515               udp0->checksum = ip_csum_fold (sum0);
1516               udp_packets++;
1517             }
1518           else
1519             {
1520               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1521                 {
1522                   udp0->src_port = s0->ext_host_nat_port;
1523                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1524                 }
1525               udp_packets++;
1526             }
1527
1528           /* Accounting */
1529           nat44_session_update_counters (s0, now,
1530                                          vlib_buffer_length_in_chain (vm, b0),
1531                                          thread_index);
1532           /* Per-user LRU list maintenance */
1533           nat44_session_update_lru (sm, s0, thread_index);
1534
1535         trace0:
1536           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1537                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1538             {
1539               nat44_ed_out2in_trace_t *t =
1540                 vlib_add_trace (vm, node, b0, sizeof (*t));
1541               t->is_slow_path = is_slow_path;
1542               t->sw_if_index = sw_if_index0;
1543               t->next_index = next0;
1544               t->session_index = ~0;
1545               if (s0)
1546                 t->session_index = s0 - tsm->sessions;
1547             }
1548
1549           pkts_processed += next0 == NAT44_ED_OUT2IN_NEXT_LOOKUP;
1550           /* verify speculative enqueue, maybe switch current next frame */
1551           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1552                                            to_next, n_left_to_next,
1553                                            bi0, next0);
1554         }
1555
1556       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1557     }
1558
1559   vlib_node_increment_counter (vm, stats_node_index,
1560                                NAT_OUT2IN_ED_ERROR_OUT2IN_PACKETS,
1561                                pkts_processed);
1562   vlib_node_increment_counter (vm, stats_node_index,
1563                                NAT_OUT2IN_ED_ERROR_TCP_PACKETS, tcp_packets);
1564   vlib_node_increment_counter (vm, stats_node_index,
1565                                NAT_OUT2IN_ED_ERROR_UDP_PACKETS, udp_packets);
1566   vlib_node_increment_counter (vm, stats_node_index,
1567                                NAT_OUT2IN_ED_ERROR_ICMP_PACKETS,
1568                                icmp_packets);
1569   vlib_node_increment_counter (vm, stats_node_index,
1570                                NAT_OUT2IN_ED_ERROR_OTHER_PACKETS,
1571                                other_packets);
1572   vlib_node_increment_counter (vm, stats_node_index,
1573                                NAT_OUT2IN_ED_ERROR_FRAGMENTS, fragments);
1574   return frame->n_vectors;
1575 }
1576
1577 VLIB_NODE_FN (nat44_ed_out2in_node) (vlib_main_t * vm,
1578                                      vlib_node_runtime_t * node,
1579                                      vlib_frame_t * frame)
1580 {
1581   return nat44_ed_out2in_node_fn_inline (vm, node, frame, 0);
1582 }
1583
1584 /* *INDENT-OFF* */
1585 VLIB_REGISTER_NODE (nat44_ed_out2in_node) = {
1586   .name = "nat44-ed-out2in",
1587   .vector_size = sizeof (u32),
1588   .format_trace = format_nat44_ed_out2in_trace,
1589   .type = VLIB_NODE_TYPE_INTERNAL,
1590   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1591   .error_strings = nat_out2in_ed_error_strings,
1592   .runtime_data_bytes = sizeof (snat_runtime_t),
1593   .n_next_nodes = NAT44_ED_OUT2IN_N_NEXT,
1594   .next_nodes = {
1595     [NAT44_ED_OUT2IN_NEXT_DROP] = "error-drop",
1596     [NAT44_ED_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
1597     [NAT44_ED_OUT2IN_NEXT_SLOW_PATH] = "nat44-ed-out2in-slowpath",
1598     [NAT44_ED_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1599     [NAT44_ED_OUT2IN_NEXT_IN2OUT] = "nat44-ed-in2out",
1600     [NAT44_ED_OUT2IN_NEXT_REASS] = "nat44-ed-out2in-reass",
1601   },
1602 };
1603 /* *INDENT-ON* */
1604
1605 VLIB_NODE_FN (nat44_ed_out2in_slowpath_node) (vlib_main_t * vm,
1606                                               vlib_node_runtime_t * node,
1607                                               vlib_frame_t * frame)
1608 {
1609   return nat44_ed_out2in_node_fn_inline (vm, node, frame, 1);
1610 }
1611
1612 /* *INDENT-OFF* */
1613 VLIB_REGISTER_NODE (nat44_ed_out2in_slowpath_node) = {
1614   .name = "nat44-ed-out2in-slowpath",
1615   .vector_size = sizeof (u32),
1616   .format_trace = format_nat44_ed_out2in_trace,
1617   .type = VLIB_NODE_TYPE_INTERNAL,
1618   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1619   .error_strings = nat_out2in_ed_error_strings,
1620   .runtime_data_bytes = sizeof (snat_runtime_t),
1621   .n_next_nodes = NAT44_ED_OUT2IN_N_NEXT,
1622   .next_nodes = {
1623     [NAT44_ED_OUT2IN_NEXT_DROP] = "error-drop",
1624     [NAT44_ED_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
1625     [NAT44_ED_OUT2IN_NEXT_SLOW_PATH] = "nat44-ed-out2in-slowpath",
1626     [NAT44_ED_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1627     [NAT44_ED_OUT2IN_NEXT_IN2OUT] = "nat44-ed-in2out",
1628     [NAT44_ED_OUT2IN_NEXT_REASS] = "nat44-ed-out2in-reass",
1629   },
1630 };
1631 /* *INDENT-ON* */
1632
1633 VLIB_NODE_FN (nat44_ed_out2in_reass_node) (vlib_main_t * vm,
1634                                            vlib_node_runtime_t * node,
1635                                            vlib_frame_t * frame)
1636 {
1637   u32 n_left_from, *from, *to_next;
1638   nat44_ed_out2in_next_t next_index;
1639   u32 pkts_processed = 0;
1640   snat_main_t *sm = &snat_main;
1641   f64 now = vlib_time_now (vm);
1642   u32 thread_index = vm->thread_index;
1643   snat_main_per_thread_data_t *per_thread_data =
1644     &sm->per_thread_data[thread_index];
1645   u32 *fragments_to_drop = 0;
1646   u32 *fragments_to_loopback = 0;
1647
1648   from = vlib_frame_vector_args (frame);
1649   n_left_from = frame->n_vectors;
1650   next_index = node->cached_next_index;
1651
1652   while (n_left_from > 0)
1653     {
1654       u32 n_left_to_next;
1655
1656       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1657
1658       while (n_left_from > 0 && n_left_to_next > 0)
1659         {
1660           u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1661           vlib_buffer_t *b0;
1662           u32 next0;
1663           u8 cached0 = 0;
1664           ip4_header_t *ip0;
1665           nat_reass_ip4_t *reass0;
1666           udp_header_t *udp0;
1667           tcp_header_t *tcp0;
1668           icmp46_header_t *icmp0;
1669           clib_bihash_kv_16_8_t kv0, value0;
1670           snat_session_t *s0 = 0;
1671           u16 old_port0, new_port0;
1672           ip_csum_t sum0;
1673           snat_session_key_t e_key0, l_key0;
1674           lb_nat_type_t lb0;
1675           twice_nat_type_t twice_nat0;
1676           u8 identity_nat0;
1677
1678           /* speculatively enqueue b0 to the current next frame */
1679           bi0 = from[0];
1680           to_next[0] = bi0;
1681           from += 1;
1682           to_next += 1;
1683           n_left_from -= 1;
1684           n_left_to_next -= 1;
1685
1686           b0 = vlib_get_buffer (vm, bi0);
1687           next0 = NAT44_ED_OUT2IN_NEXT_LOOKUP;
1688
1689           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1690           rx_fib_index0 =
1691             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1692                                                  sw_if_index0);
1693
1694           if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1695             {
1696               next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1697               b0->error = node->errors[NAT_OUT2IN_ED_ERROR_DROP_FRAGMENT];
1698               goto trace0;
1699             }
1700
1701           ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
1702           udp0 = ip4_next_header (ip0);
1703           tcp0 = (tcp_header_t *) udp0;
1704           icmp0 = (icmp46_header_t *) udp0;
1705           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1706
1707           reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1708                                                  ip0->dst_address,
1709                                                  ip0->fragment_id,
1710                                                  ip0->protocol,
1711                                                  1, &fragments_to_drop);
1712
1713           if (PREDICT_FALSE (!reass0))
1714             {
1715               next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1716               b0->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_REASS];
1717               nat_elog_notice ("maximum reassemblies exceeded");
1718               goto trace0;
1719             }
1720
1721           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1722             {
1723               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1724                 {
1725                   next0 = icmp_out2in_ed_slow_path
1726                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1727                      next0, now, thread_index, &s0);
1728
1729                   if (PREDICT_TRUE (next0 != NAT44_ED_OUT2IN_NEXT_DROP))
1730                     {
1731                       if (s0)
1732                         reass0->sess_index = s0 - per_thread_data->sessions;
1733                       else
1734                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1735                       reass0->thread_index = thread_index;
1736                       nat_ip4_reass_get_frags (reass0,
1737                                                &fragments_to_loopback);
1738                     }
1739
1740                   goto trace0;
1741                 }
1742
1743               make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
1744                           ip0->protocol, rx_fib_index0, udp0->dst_port,
1745                           udp0->src_port);
1746
1747               if (clib_bihash_search_16_8
1748                   (&per_thread_data->out2in_ed, &kv0, &value0))
1749                 {
1750                   /* Try to match static mapping by external address and port,
1751                      destination address and port in packet */
1752                   e_key0.addr = ip0->dst_address;
1753                   e_key0.port = udp0->dst_port;
1754                   e_key0.protocol = proto0;
1755                   e_key0.fib_index = rx_fib_index0;
1756                   if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
1757                                                  &twice_nat0, &lb0, 0,
1758                                                  &identity_nat0))
1759                     {
1760                       /*
1761                        * Send DHCP packets to the ipv4 stack, or we won't
1762                        * be able to use dhcp client on the outside interface
1763                        */
1764                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1765                                          && (udp0->dst_port
1766                                              ==
1767                                              clib_host_to_net_u16
1768                                              (UDP_DST_PORT_dhcp_to_client))))
1769                         {
1770                           vnet_feature_next (&next0, b0);
1771                           goto trace0;
1772                         }
1773
1774                       if (!sm->forwarding_enabled)
1775                         {
1776                           b0->error =
1777                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1778                           next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1779                         }
1780                       else
1781                         {
1782                           if (next_src_nat (sm, ip0, ip0->protocol,
1783                                             udp0->src_port, udp0->dst_port,
1784                                             thread_index, rx_fib_index0))
1785                             {
1786                               next0 = NAT44_ED_OUT2IN_NEXT_IN2OUT;
1787                               goto trace0;
1788                             }
1789                           if (sm->num_workers > 1)
1790                             create_bypass_for_fwd_worker (sm, ip0,
1791                                                           rx_fib_index0);
1792                           else
1793                             create_bypass_for_fwd (sm, ip0, rx_fib_index0,
1794                                                    thread_index);
1795                           reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1796                           nat_ip4_reass_get_frags (reass0,
1797                                                    &fragments_to_loopback);
1798                         }
1799                       goto trace0;
1800                     }
1801
1802                   if (PREDICT_FALSE (identity_nat0))
1803                     {
1804                       reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1805                       goto trace0;
1806                     }
1807
1808                   if ((proto0 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp0))
1809                     {
1810                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1811                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1812                       goto trace0;
1813                     }
1814
1815                   /* Create session initiated by host from external network */
1816                   s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
1817                                                              e_key0, node,
1818                                                              thread_index,
1819                                                              twice_nat0, lb0,
1820                                                              now);
1821                   if (!s0)
1822                     {
1823                       b0->error =
1824                         node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1825                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1826                       goto trace0;
1827                     }
1828                   reass0->sess_index = s0 - per_thread_data->sessions;
1829                   reass0->thread_index = thread_index;
1830                 }
1831               else
1832                 {
1833                   s0 = pool_elt_at_index (per_thread_data->sessions,
1834                                           value0.value);
1835                   reass0->sess_index = value0.value;
1836                 }
1837               nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1838             }
1839           else
1840             {
1841               if (reass0->flags & NAT_REASS_FLAG_ED_DONT_TRANSLATE)
1842                 goto trace0;
1843               if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1844                 {
1845                   if (nat_ip4_reass_add_fragment
1846                       (thread_index, reass0, bi0, &fragments_to_drop))
1847                     {
1848                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_FRAG];
1849                       nat_elog_notice
1850                         ("maximum fragments per reassembly exceeded");
1851                       next0 = NAT44_ED_OUT2IN_NEXT_DROP;
1852                       goto trace0;
1853                     }
1854                   cached0 = 1;
1855                   goto trace0;
1856                 }
1857               s0 = pool_elt_at_index (per_thread_data->sessions,
1858                                       reass0->sess_index);
1859             }
1860
1861           old_addr0 = ip0->dst_address.as_u32;
1862           ip0->dst_address = s0->in2out.addr;
1863           new_addr0 = ip0->dst_address.as_u32;
1864           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1865
1866           sum0 = ip0->checksum;
1867           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1868                                  ip4_header_t,
1869                                  dst_address /* changed member */ );
1870           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1871             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1872                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
1873                                    src_address);
1874           ip0->checksum = ip_csum_fold (sum0);
1875
1876           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1877             {
1878               old_port0 = udp0->dst_port;
1879               new_port0 = udp0->dst_port = s0->in2out.port;
1880
1881               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1882                 {
1883                   sum0 = tcp0->checksum;
1884                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1885                                          ip4_header_t,
1886                                          dst_address /* changed member */ );
1887
1888                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1889                                          ip4_header_t /* cheat */ ,
1890                                          length /* changed member */ );
1891                   if (is_twice_nat_session (s0))
1892                     {
1893                       sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1894                                              s0->ext_host_nat_addr.as_u32,
1895                                              ip4_header_t, dst_address);
1896                       sum0 = ip_csum_update (sum0, tcp0->src_port,
1897                                              s0->ext_host_nat_port,
1898                                              ip4_header_t, length);
1899                       tcp0->src_port = s0->ext_host_nat_port;
1900                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1901                     }
1902                   tcp0->checksum = ip_csum_fold (sum0);
1903                 }
1904               else if (udp0->checksum)
1905                 {
1906                   sum0 = udp0->checksum;
1907                   sum0 =
1908                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1909                                     dst_address);
1910                   sum0 =
1911                     ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1912                                     length);
1913                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1914                     {
1915                       sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1916                                              s0->ext_host_nat_addr.as_u32,
1917                                              ip4_header_t, dst_address);
1918                       sum0 = ip_csum_update (sum0, udp0->src_port,
1919                                              s0->ext_host_nat_port,
1920                                              ip4_header_t, length);
1921                       udp0->src_port = s0->ext_host_nat_port;
1922                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1923                     }
1924                   udp0->checksum = ip_csum_fold (sum0);
1925                 }
1926               else
1927                 {
1928                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1929                     {
1930                       udp0->src_port = s0->ext_host_nat_port;
1931                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1932                     }
1933                 }
1934             }
1935
1936           /* Accounting */
1937           nat44_session_update_counters (s0, now,
1938                                          vlib_buffer_length_in_chain (vm, b0),
1939                                          thread_index);
1940           /* Per-user LRU list maintenance */
1941           nat44_session_update_lru (sm, s0, thread_index);
1942
1943         trace0:
1944           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1945                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1946             {
1947               nat44_reass_trace_t *t =
1948                 vlib_add_trace (vm, node, b0, sizeof (*t));
1949               t->cached = cached0;
1950               t->sw_if_index = sw_if_index0;
1951               t->next_index = next0;
1952             }
1953
1954           if (cached0)
1955             {
1956               n_left_to_next++;
1957               to_next--;
1958             }
1959           else
1960             {
1961               pkts_processed += next0 != NAT44_ED_OUT2IN_NEXT_DROP;
1962
1963               /* verify speculative enqueue, maybe switch current next frame */
1964               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1965                                                to_next, n_left_to_next,
1966                                                bi0, next0);
1967             }
1968
1969           if (n_left_from == 0 && vec_len (fragments_to_loopback))
1970             {
1971               from = vlib_frame_vector_args (frame);
1972               u32 len = vec_len (fragments_to_loopback);
1973               if (len <= VLIB_FRAME_SIZE)
1974                 {
1975                   clib_memcpy_fast (from, fragments_to_loopback,
1976                                     sizeof (u32) * len);
1977                   n_left_from = len;
1978                   vec_reset_length (fragments_to_loopback);
1979                 }
1980               else
1981                 {
1982                   clib_memcpy_fast (from, fragments_to_loopback +
1983                                     (len - VLIB_FRAME_SIZE),
1984                                     sizeof (u32) * VLIB_FRAME_SIZE);
1985                   n_left_from = VLIB_FRAME_SIZE;
1986                   _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
1987                 }
1988             }
1989         }
1990
1991       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1992     }
1993
1994   vlib_node_increment_counter (vm, sm->ed_out2in_reass_node_index,
1995                                NAT_OUT2IN_ED_ERROR_OUT2IN_PACKETS,
1996                                pkts_processed);
1997
1998   nat_send_all_to_node (vm, fragments_to_drop, node,
1999                         &node->errors[NAT_OUT2IN_ED_ERROR_DROP_FRAGMENT],
2000                         NAT44_ED_OUT2IN_NEXT_DROP);
2001
2002   vec_free (fragments_to_drop);
2003   vec_free (fragments_to_loopback);
2004   return frame->n_vectors;
2005 }
2006
2007 /* *INDENT-OFF* */
2008 VLIB_REGISTER_NODE (nat44_ed_out2in_reass_node) = {
2009   .name = "nat44-ed-out2in-reass",
2010   .vector_size = sizeof (u32),
2011   .format_trace = format_nat44_reass_trace,
2012   .type = VLIB_NODE_TYPE_INTERNAL,
2013   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
2014   .error_strings = nat_out2in_ed_error_strings,
2015   .n_next_nodes = NAT44_ED_OUT2IN_N_NEXT,
2016   .next_nodes = {
2017     [NAT44_ED_OUT2IN_NEXT_DROP] = "error-drop",
2018     [NAT44_ED_OUT2IN_NEXT_LOOKUP] = "ip4-lookup",
2019     [NAT44_ED_OUT2IN_NEXT_SLOW_PATH] = "nat44-ed-out2in-slowpath",
2020     [NAT44_ED_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2021     [NAT44_ED_OUT2IN_NEXT_IN2OUT] = "nat44-ed-in2out",
2022     [NAT44_ED_OUT2IN_NEXT_REASS] = "nat44-ed-out2in-reass",
2023   },
2024 };
2025 /* *INDENT-ON* */
2026
2027 /*
2028  * fd.io coding-style-patch-verification: ON
2029  *
2030  * Local Variables:
2031  * eval: (c-set-style "gnu")
2032  * End:
2033  */