src/plugins/nat/in2out.c

   1 /*
   2  * Copyright (c) 2016 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 inside to outside network translation
  18  */
  19
  20 #include <vlib/vlib.h>
  21 #include <vnet/vnet.h>
  22 #include <vnet/pg/pg.h>
  23
  24 #include <vnet/ip/ip.h>
  25 #include <vnet/ethernet/ethernet.h>
  26 #include <vnet/fib/ip4_fib.h>
  27 #include <vnet/udp/udp.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 #include <vppinfra/hash.h>
  36 #include <vppinfra/error.h>
  37 #include <vppinfra/elog.h>
  38 #include <nat/lib/nat_inlines.h>
  39
  40 typedef struct
  41 {
  42   u32 sw_if_index;
  43   u32 next_index;
  44   u32 session_index;
  45   u32 is_slow_path;
  46   u32 is_hairpinning;
  47 } snat_in2out_trace_t;
  48
  49 /* packet trace format function */
  50 static u8 *
  51 format_snat_in2out_trace (u8 * s, va_list * args)
  52 {
  53   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  54   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  55   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  56   char *tag;
  57
  58   tag = t->is_slow_path ? "NAT44_IN2OUT_SLOW_PATH" : "NAT44_IN2OUT_FAST_PATH";
  59
  60   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  61               t->sw_if_index, t->next_index, t->session_index);
  62   if (t->is_hairpinning)
  63     {
  64       s = format (s, ", with-hairpinning");
  65     }
  66
  67   return s;
  68 }
  69
  70 static u8 *
  71 format_snat_in2out_fast_trace (u8 * s, va_list * args)
  72 {
  73   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  74   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  75   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  76
  77   s = format (s, "NAT44_IN2OUT_FAST: sw_if_index %d, next index %d",
  78               t->sw_if_index, t->next_index);
  79
  80   return s;
  81 }
  82
  83 #define foreach_snat_in2out_error                       \
  84 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
  85 _(OUT_OF_PORTS, "out of ports")                         \
  86 _(BAD_OUTSIDE_FIB, "outside VRF ID not found")          \
  87 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  88 _(NO_TRANSLATION, "no translation")                     \
  89 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
  90 _(CANNOT_CREATE_USER, "cannot create NAT user")
  91
  92 typedef enum
  93 {
  94 #define _(sym,str) SNAT_IN2OUT_ERROR_##sym,
  95   foreach_snat_in2out_error
  96 #undef _
  97     SNAT_IN2OUT_N_ERROR,
  98 } snat_in2out_error_t;
  99
 100 static char *snat_in2out_error_strings[] = {
 101 #define _(sym,string) string,
 102   foreach_snat_in2out_error
 103 #undef _
 104 };
 105
 106 typedef enum
 107 {
 108   SNAT_IN2OUT_NEXT_LOOKUP,
 109   SNAT_IN2OUT_NEXT_DROP,
 110   SNAT_IN2OUT_NEXT_ICMP_ERROR,
 111   SNAT_IN2OUT_NEXT_SLOW_PATH,
 112   SNAT_IN2OUT_N_NEXT,
 113 } snat_in2out_next_t;
 114
 115 static inline int
 116 snat_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 117                     u32 sw_if_index0, ip4_header_t * ip0, u32 proto0,
 118                     u32 rx_fib_index0, u32 thread_index)
 119 {
 120   udp_header_t *udp0 = ip4_next_header (ip0);
 121   clib_bihash_kv_8_8_t kv0, value0;
 122
 123   init_nat_k (&kv0, ip0->dst_address, udp0->dst_port, sm->outside_fib_index,
 124               proto0);
 125
 126   /* NAT packet aimed at external address if */
 127   /* has active sessions */
 128   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
 129                               &value0))
 130     {
 131       /* or is static mappings */
 132       ip4_address_t placeholder_addr;
 133       u16 placeholder_port;
 134       u32 placeholder_fib_index;
 135       if (!snat_static_mapping_match
 136           (sm, ip0->dst_address, udp0->dst_port, sm->outside_fib_index,
 137            proto0, &placeholder_addr, &placeholder_port,
 138            &placeholder_fib_index, 1, 0, 0, 0, 0, 0, 0))
 139         return 0;
 140     }
 141   else
 142     return 0;
 143
 144   if (sm->forwarding_enabled)
 145     return 1;
 146
 147   return snat_not_translate_fast (sm, node, sw_if_index0, ip0, proto0,
 148                                   rx_fib_index0);
 149 }
 150
 151 static inline int
 152 nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
 153                                   u32 proto0, u16 src_port, u16 dst_port,
 154                                   u32 thread_index, u32 sw_if_index)
 155 {
 156   clib_bihash_kv_8_8_t kv0, value0;
 157   snat_interface_t *i;
 158
 159   /* src NAT check */
 160   init_nat_k (&kv0, ip0->src_address, src_port,
 161               ip4_fib_table_get_index_for_sw_if_index (sw_if_index), proto0);
 162
 163   if (!clib_bihash_search_8_8
 164       (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
 165     return 1;
 166
 167   /* dst NAT check */
 168   init_nat_k (&kv0, ip0->dst_address, dst_port,
 169               ip4_fib_table_get_index_for_sw_if_index (sw_if_index), proto0);
 170   if (!clib_bihash_search_8_8
 171       (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
 172     {
 173       /* hairpinning */
 174     /* *INDENT-OFF* */
 175     pool_foreach (i, sm->output_feature_interfaces,
 176     ({
 177       if ((nat_interface_is_inside(i)) && (sw_if_index == i->sw_if_index))
 178         return 0;
 179     }));
 180     /* *INDENT-ON* */
 181       return 1;
 182     }
 183
 184   return 0;
 185 }
 186
 187 #ifndef CLIB_MARCH_VARIANT
 188 int
 189 nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
 190 {
 191   snat_main_t *sm = &snat_main;
 192   nat44_is_idle_session_ctx_t *ctx = arg;
 193   snat_session_t *s;
 194   u64 sess_timeout_time;
 195   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 196                                                        ctx->thread_index);
 197   clib_bihash_kv_8_8_t s_kv;
 198
 199   s = pool_elt_at_index (tsm->sessions, kv->value);
 200   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 201   if (ctx->now >= sess_timeout_time)
 202     {
 203       init_nat_o2i_k (&s_kv, s);
 204       if (clib_bihash_add_del_8_8 (&tsm->out2in, &s_kv, 0))
 205         nat_elog_warn ("out2in key del failed");
 206
 207       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 208                                            s->in2out.addr.as_u32,
 209                                            s->out2in.addr.as_u32,
 210                                            s->nat_proto,
 211                                            s->in2out.port,
 212                                            s->out2in.port,
 213                                            s->in2out.fib_index);
 214
 215       nat_syslog_nat44_apmdel (s->user_index, s->in2out.fib_index,
 216                                &s->in2out.addr, s->in2out.port,
 217                                &s->out2in.addr, s->out2in.port, s->nat_proto);
 218
 219       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 220                    s->ext_host_port, s->nat_proto, s->out2in.fib_index,
 221                    ctx->thread_index);
 222
 223       if (!snat_is_session_static (s))
 224         snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 225                                             &s->out2in.addr,
 226                                             s->out2in.port, s->nat_proto);
 227
 228       nat44_delete_session (sm, s, ctx->thread_index);
 229       return 1;
 230     }
 231
 232   return 0;
 233 }
 234 #endif
 235
 236 static u32
 237 slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 238            ip4_header_t * ip0,
 239            ip4_address_t i2o_addr,
 240            u16 i2o_port,
 241            u32 rx_fib_index0,
 242            nat_protocol_t nat_proto,
 243            snat_session_t ** sessionp,
 244            vlib_node_runtime_t * node, u32 next0, u32 thread_index, f64 now)
 245 {
 246   snat_user_t *u;
 247   snat_session_t *s = 0;
 248   clib_bihash_kv_8_8_t kv0;
 249   u8 is_sm = 0;
 250   nat_outside_fib_t *outside_fib;
 251   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 252   u8 identity_nat;
 253   fib_prefix_t pfx = {
 254     .fp_proto = FIB_PROTOCOL_IP4,
 255     .fp_len = 32,
 256     .fp_addr = {
 257                 .ip4.as_u32 = ip0->dst_address.as_u32,
 258                 },
 259   };
 260   nat44_is_idle_session_ctx_t ctx0;
 261   ip4_address_t sm_addr;
 262   u16 sm_port;
 263   u32 sm_fib_index;
 264
 265   if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 266     {
 267       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_SESSIONS_EXCEEDED];
 268       nat_ipfix_logging_max_sessions (thread_index,
 269                                       sm->max_translations_per_thread);
 270       nat_elog_notice ("maximum sessions exceeded");
 271       return SNAT_IN2OUT_NEXT_DROP;
 272     }
 273
 274   /* First try to match static mapping by local address and port */
 275   if (snat_static_mapping_match
 276       (sm, i2o_addr, i2o_port, rx_fib_index0, nat_proto, &sm_addr,
 277        &sm_port, &sm_fib_index, 0, 0, 0, 0, 0, &identity_nat, 0))
 278     {
 279       /* Try to create dynamic translation */
 280       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index0,
 281                                                thread_index,
 282                                                nat_proto,
 283                                                &sm_addr, &sm_port,
 284                                                sm->port_per_thread,
 285                                                sm->per_thread_data
 286                                                [thread_index].snat_thread_index))
 287         {
 288           b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
 289           return SNAT_IN2OUT_NEXT_DROP;
 290         }
 291     }
 292   else
 293     {
 294       if (PREDICT_FALSE (identity_nat))
 295         {
 296           *sessionp = s;
 297           return next0;
 298         }
 299
 300       is_sm = 1;
 301     }
 302
 303   u = nat_user_get_or_create (sm, &ip0->src_address, rx_fib_index0,
 304                               thread_index);
 305   if (!u)
 306     {
 307       b0->error = node->errors[SNAT_IN2OUT_ERROR_CANNOT_CREATE_USER];
 308       return SNAT_IN2OUT_NEXT_DROP;
 309     }
 310
 311   s = nat_session_alloc_or_recycle (sm, u, thread_index, now);
 312   if (!s)
 313     {
 314       nat44_delete_user_with_no_session (sm, u, thread_index);
 315       nat_elog_warn ("create NAT session failed");
 316       return SNAT_IN2OUT_NEXT_DROP;
 317     }
 318
 319   if (is_sm)
 320     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 321   user_session_increment (sm, u, is_sm);
 322   s->in2out.addr = i2o_addr;
 323   s->in2out.port = i2o_port;
 324   s->in2out.fib_index = rx_fib_index0;
 325   s->nat_proto = nat_proto;
 326   s->out2in.addr = sm_addr;
 327   s->out2in.port = sm_port;
 328   s->out2in.fib_index = sm->outside_fib_index;
 329   switch (vec_len (sm->outside_fibs))
 330     {
 331     case 0:
 332       s->out2in.fib_index = sm->outside_fib_index;
 333       break;
 334     case 1:
 335       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 336       break;
 337     default:
 338       /* *INDENT-OFF* */
 339       vec_foreach (outside_fib, sm->outside_fibs)
 340         {
 341           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 342           if (FIB_NODE_INDEX_INVALID != fei)
 343             {
 344               if (fib_entry_get_resolving_interface (fei) != ~0)
 345                 {
 346                   s->out2in.fib_index = outside_fib->fib_index;
 347                   break;
 348                 }
 349             }
 350         }
 351       /* *INDENT-ON* */
 352       break;
 353     }
 354   s->ext_host_addr.as_u32 = ip0->dst_address.as_u32;
 355   s->ext_host_port = vnet_buffer (b0)->ip.reass.l4_dst_port;
 356   *sessionp = s;
 357
 358   /* Add to translation hashes */
 359   ctx0.now = now;
 360   ctx0.thread_index = thread_index;
 361   init_nat_i2o_kv (&kv0, s, s - sm->per_thread_data[thread_index].sessions);
 362   if (clib_bihash_add_or_overwrite_stale_8_8
 363       (&sm->per_thread_data[thread_index].in2out, &kv0,
 364        nat44_i2o_is_idle_session_cb, &ctx0))
 365     nat_elog_notice ("in2out key add failed");
 366
 367   init_nat_o2i_kv (&kv0, s, s - sm->per_thread_data[thread_index].sessions);
 368   if (clib_bihash_add_or_overwrite_stale_8_8
 369       (&sm->per_thread_data[thread_index].out2in, &kv0,
 370        nat44_o2i_is_idle_session_cb, &ctx0))
 371     nat_elog_notice ("out2in key add failed");
 372
 373   /* log NAT event */
 374   snat_ipfix_logging_nat44_ses_create (thread_index,
 375                                        s->in2out.addr.as_u32,
 376                                        s->out2in.addr.as_u32,
 377                                        s->nat_proto,
 378                                        s->in2out.port,
 379                                        s->out2in.port, s->in2out.fib_index);
 380
 381   nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
 382                            &s->in2out.addr, s->in2out.port, &s->out2in.addr,
 383                            s->out2in.port, s->nat_proto);
 384
 385   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 386                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 387                &s->ext_host_nat_addr, s->ext_host_nat_port,
 388                s->nat_proto, s->in2out.fib_index, s->flags, thread_index, 0);
 389
 390   return next0;
 391 }
 392
 393 #ifndef CLIB_MARCH_VARIANT
 394 static_always_inline snat_in2out_error_t
 395 icmp_get_key (vlib_buffer_t * b, ip4_header_t * ip0,
 396               ip4_address_t * addr, u16 * port, nat_protocol_t * nat_proto)
 397 {
 398   icmp46_header_t *icmp0;
 399   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 400   ip4_header_t *inner_ip0 = 0;
 401   void *l4_header = 0;
 402   icmp46_header_t *inner_icmp0;
 403
 404   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 405   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 406
 407   if (!icmp_type_is_error_message
 408       (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
 409     {
 410       *nat_proto = NAT_PROTOCOL_ICMP;
 411       *addr = ip0->src_address;
 412       *port = vnet_buffer (b)->ip.reass.l4_src_port;
 413     }
 414   else
 415     {
 416       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 417       l4_header = ip4_next_header (inner_ip0);
 418       *nat_proto = ip_proto_to_nat_proto (inner_ip0->protocol);
 419       *addr = inner_ip0->dst_address;
 420       switch (*nat_proto)
 421         {
 422         case NAT_PROTOCOL_ICMP:
 423           inner_icmp0 = (icmp46_header_t *) l4_header;
 424           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 425           *port = inner_echo0->identifier;
 426           break;
 427         case NAT_PROTOCOL_UDP:
 428         case NAT_PROTOCOL_TCP:
 429           *port = ((tcp_udp_header_t *) l4_header)->dst_port;
 430           break;
 431         default:
 432           return SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL;
 433         }
 434     }
 435   return -1;                    /* success */
 436 }
 437
 438 /**
 439  * Get address and port values to be used for ICMP packet translation
 440  * and create session if needed
 441  *
 442  * @param[in,out] sm             NAT main
 443  * @param[in,out] node           NAT node runtime
 444  * @param[in] thread_index       thread index
 445  * @param[in,out] b0             buffer containing packet to be translated
 446  * @param[in,out] ip0            ip header
 447  * @param[out] p_proto           protocol used for matching
 448  * @param[out] p_value           address and port after NAT translation
 449  * @param[out] p_dont_translate  if packet should not be translated
 450  * @param d                      optional parameter
 451  * @param e                      optional parameter
 452  */
 453 u32
 454 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
 455                         u32 thread_index, vlib_buffer_t * b0,
 456                         ip4_header_t * ip0, ip4_address_t * addr, u16 * port,
 457                         u32 * fib_index, nat_protocol_t * proto, void *d,
 458                         void *e, u8 * dont_translate)
 459 {
 460   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 461   u32 sw_if_index0;
 462   snat_session_t *s0 = 0;
 463   clib_bihash_kv_8_8_t kv0, value0;
 464   u32 next0 = ~0;
 465   int err;
 466   vlib_main_t *vm = vlib_get_main ();
 467   *dont_translate = 0;
 468
 469   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 470   *fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 471
 472   err = icmp_get_key (b0, ip0, addr, port, proto);
 473   if (err != -1)
 474     {
 475       b0->error = node->errors[err];
 476       next0 = SNAT_IN2OUT_NEXT_DROP;
 477       goto out;
 478     }
 479
 480   init_nat_k (&kv0, *addr, *port, *fib_index, *proto);
 481   if (clib_bihash_search_8_8 (&tsm->in2out, &kv0, &value0))
 482     {
 483       if (vnet_buffer (b0)->sw_if_index[VLIB_TX] != ~0)
 484         {
 485           if (PREDICT_FALSE
 486               (nat_not_translate_output_feature
 487                (sm, ip0, *proto, *port, *port, thread_index, sw_if_index0)))
 488             {
 489               *dont_translate = 1;
 490               goto out;
 491             }
 492         }
 493       else
 494         {
 495           if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
 496                                                  ip0, NAT_PROTOCOL_ICMP,
 497                                                  *fib_index, thread_index)))
 498             {
 499               *dont_translate = 1;
 500               goto out;
 501             }
 502         }
 503
 504       if (PREDICT_FALSE
 505           (icmp_type_is_error_message
 506            (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags)))
 507         {
 508           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 509           next0 = SNAT_IN2OUT_NEXT_DROP;
 510           goto out;
 511         }
 512
 513       next0 =
 514         slow_path (sm, b0, ip0, *addr, *port, *fib_index, *proto, &s0, node,
 515                    next0, thread_index, vlib_time_now (vm));
 516
 517       if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
 518         goto out;
 519
 520       if (!s0)
 521         {
 522           *dont_translate = 1;
 523           goto out;
 524         }
 525     }
 526   else
 527     {
 528       if (PREDICT_FALSE
 529           (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 530            ICMP4_echo_request
 531            && vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 532            ICMP4_echo_reply
 533            && !icmp_type_is_error_message (vnet_buffer (b0)->ip.
 534                                            reass.icmp_type_or_tcp_flags)))
 535         {
 536           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 537           next0 = SNAT_IN2OUT_NEXT_DROP;
 538           goto out;
 539         }
 540
 541       s0 = pool_elt_at_index (tsm->sessions, value0.value);
 542     }
 543
 544 out:
 545   if (s0)
 546     {
 547       *addr = s0->out2in.addr;
 548       *port = s0->out2in.port;
 549       *fib_index = s0->out2in.fib_index;
 550     }
 551   if (d)
 552     *(snat_session_t **) (d) = s0;
 553   return next0;
 554 }
 555 #endif
 556
 557 #ifndef CLIB_MARCH_VARIANT
 558 /**
 559  * Get address and port values to be used for ICMP packet translation
 560  *
 561  * @param[in] sm                 NAT main
 562  * @param[in,out] node           NAT node runtime
 563  * @param[in] thread_index       thread index
 564  * @param[in,out] b0             buffer containing packet to be translated
 565  * @param[in,out] ip0            ip header
 566  * @param[out] p_proto           protocol used for matching
 567  * @param[out] p_value           address and port after NAT translation
 568  * @param[out] p_dont_translate  if packet should not be translated
 569  * @param d                      optional parameter
 570  * @param e                      optional parameter
 571  */
 572 u32
 573 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
 574                         u32 thread_index, vlib_buffer_t * b0,
 575                         ip4_header_t * ip0, ip4_address_t * addr, u16 * port,
 576                         u32 * fib_index, nat_protocol_t * proto, void *d,
 577                         void *e, u8 * dont_translate)
 578 {
 579   u32 sw_if_index0;
 580   u8 is_addr_only;
 581   u32 next0 = ~0;
 582   int err;
 583   *dont_translate = 0;
 584
 585   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 586   *fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 587
 588   err = icmp_get_key (b0, ip0, addr, port, proto);
 589   if (err != -1)
 590     {
 591       b0->error = node->errors[err];
 592       next0 = SNAT_IN2OUT_NEXT_DROP;
 593       goto out;
 594     }
 595
 596   ip4_address_t sm_addr;
 597   u16 sm_port;
 598   u32 sm_fib_index;
 599
 600   if (snat_static_mapping_match
 601       (sm, *addr, *port, *fib_index, *proto, &sm_addr, &sm_port,
 602        &sm_fib_index, 0, &is_addr_only, 0, 0, 0, 0, 0))
 603     {
 604       if (PREDICT_FALSE (snat_not_translate_fast (sm, node, sw_if_index0, ip0,
 605                                                   IP_PROTOCOL_ICMP,
 606                                                   *fib_index)))
 607         {
 608           *dont_translate = 1;
 609           goto out;
 610         }
 611
 612       if (icmp_type_is_error_message
 613           (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags))
 614         {
 615           next0 = SNAT_IN2OUT_NEXT_DROP;
 616           goto out;
 617         }
 618
 619       b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
 620       next0 = SNAT_IN2OUT_NEXT_DROP;
 621       goto out;
 622     }
 623
 624   if (PREDICT_FALSE
 625       (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_request
 626        && (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 627            ICMP4_echo_reply || !is_addr_only)
 628        && !icmp_type_is_error_message (vnet_buffer (b0)->ip.
 629                                        reass.icmp_type_or_tcp_flags)))
 630     {
 631       b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 632       next0 = SNAT_IN2OUT_NEXT_DROP;
 633       goto out;
 634     }
 635
 636 out:
 637   return next0;
 638 }
 639 #endif
 640
 641 #ifndef CLIB_MARCH_VARIANT
 642 u32
 643 icmp_in2out (snat_main_t * sm,
 644              vlib_buffer_t * b0,
 645              ip4_header_t * ip0,
 646              icmp46_header_t * icmp0,
 647              u32 sw_if_index0,
 648              u32 rx_fib_index0,
 649              vlib_node_runtime_t * node,
 650              u32 next0, u32 thread_index, void *d, void *e)
 651 {
 652   vlib_main_t *vm = vlib_get_main ();
 653   ip4_address_t addr;
 654   u16 port;
 655   u32 fib_index;
 656   nat_protocol_t protocol;
 657   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 658   ip4_header_t *inner_ip0;
 659   void *l4_header = 0;
 660   icmp46_header_t *inner_icmp0;
 661   u8 dont_translate;
 662   u32 new_addr0, old_addr0;
 663   u16 old_id0, new_id0;
 664   u16 old_checksum0, new_checksum0;
 665   ip_csum_t sum0;
 666   u16 checksum0;
 667   u32 next0_tmp;
 668
 669   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 670
 671   next0_tmp =
 672     sm->icmp_match_in2out_cb (sm, node, thread_index, b0, ip0, &addr, &port,
 673                               &fib_index, &protocol, d, e, &dont_translate);
 674   if (next0_tmp != ~0)
 675     next0 = next0_tmp;
 676   if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
 677     goto out;
 678
 679   if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
 680     {
 681       sum0 =
 682         ip_incremental_checksum_buffer (vm, b0,
 683                                         (u8 *) icmp0 -
 684                                         (u8 *) vlib_buffer_get_current (b0),
 685                                         ntohs (ip0->length) -
 686                                         ip4_header_bytes (ip0), 0);
 687       checksum0 = ~ip_csum_fold (sum0);
 688       if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff))
 689         {
 690           next0 = SNAT_IN2OUT_NEXT_DROP;
 691           goto out;
 692         }
 693     }
 694
 695   old_addr0 = ip0->src_address.as_u32;
 696   new_addr0 = ip0->src_address.as_u32 = addr.as_u32;
 697
 698   sum0 = ip0->checksum;
 699   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 700                          src_address /* changed member */ );
 701   ip0->checksum = ip_csum_fold (sum0);
 702
 703   if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 704     {
 705       if (icmp0->checksum == 0)
 706         icmp0->checksum = 0xffff;
 707
 708       if (!icmp_type_is_error_message (icmp0->type))
 709         {
 710           new_id0 = port;
 711           if (PREDICT_FALSE (new_id0 != echo0->identifier))
 712             {
 713               old_id0 = echo0->identifier;
 714               new_id0 = port;
 715               echo0->identifier = new_id0;
 716
 717               sum0 = icmp0->checksum;
 718               sum0 =
 719                 ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 720                                 identifier);
 721               icmp0->checksum = ip_csum_fold (sum0);
 722             }
 723         }
 724       else
 725         {
 726           inner_ip0 = (ip4_header_t *) (echo0 + 1);
 727           l4_header = ip4_next_header (inner_ip0);
 728
 729           if (!ip4_header_checksum_is_valid (inner_ip0))
 730             {
 731               next0 = SNAT_IN2OUT_NEXT_DROP;
 732               goto out;
 733             }
 734
 735           /* update inner destination IP address */
 736           old_addr0 = inner_ip0->dst_address.as_u32;
 737           inner_ip0->dst_address = addr;
 738           new_addr0 = inner_ip0->dst_address.as_u32;
 739           sum0 = icmp0->checksum;
 740           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 741                                  dst_address /* changed member */ );
 742           icmp0->checksum = ip_csum_fold (sum0);
 743
 744           /* update inner IP header checksum */
 745           old_checksum0 = inner_ip0->checksum;
 746           sum0 = inner_ip0->checksum;
 747           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 748                                  dst_address /* changed member */ );
 749           inner_ip0->checksum = ip_csum_fold (sum0);
 750           new_checksum0 = inner_ip0->checksum;
 751           sum0 = icmp0->checksum;
 752           sum0 =
 753             ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
 754                             checksum);
 755           icmp0->checksum = ip_csum_fold (sum0);
 756
 757           switch (protocol)
 758             {
 759             case NAT_PROTOCOL_ICMP:
 760               inner_icmp0 = (icmp46_header_t *) l4_header;
 761               inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 762
 763               old_id0 = inner_echo0->identifier;
 764               new_id0 = port;
 765               inner_echo0->identifier = new_id0;
 766
 767               sum0 = icmp0->checksum;
 768               sum0 =
 769                 ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 770                                 identifier);
 771               icmp0->checksum = ip_csum_fold (sum0);
 772               break;
 773             case NAT_PROTOCOL_UDP:
 774             case NAT_PROTOCOL_TCP:
 775               old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
 776               new_id0 = port;
 777               ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
 778
 779               sum0 = icmp0->checksum;
 780               sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
 781                                      dst_port);
 782               icmp0->checksum = ip_csum_fold (sum0);
 783               break;
 784             default:
 785               ASSERT (0);
 786             }
 787         }
 788     }
 789
 790   if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
 791     {
 792       if (0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
 793                                       sm->endpoint_dependent))
 794         vnet_buffer (b0)->sw_if_index[VLIB_TX] = fib_index;
 795     }
 796
 797 out:
 798   return next0;
 799 }
 800 #endif
 801
 802 static inline u32
 803 icmp_in2out_slow_path (snat_main_t * sm,
 804                        vlib_buffer_t * b0,
 805                        ip4_header_t * ip0,
 806                        icmp46_header_t * icmp0,
 807                        u32 sw_if_index0,
 808                        u32 rx_fib_index0,
 809                        vlib_node_runtime_t * node,
 810                        u32 next0,
 811                        f64 now, u32 thread_index, snat_session_t ** p_s0)
 812 {
 813   vlib_main_t *vm = vlib_get_main ();
 814
 815   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 816                        next0, thread_index, p_s0, 0);
 817   snat_session_t *s0 = *p_s0;
 818   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
 819     {
 820       /* Accounting */
 821       nat44_session_update_counters (s0, now,
 822                                      vlib_buffer_length_in_chain
 823                                      (vm, b0), thread_index);
 824       /* Per-user LRU list maintenance */
 825       nat44_session_update_lru (sm, s0, thread_index);
 826     }
 827   return next0;
 828 }
 829
 830 static int
 831 nat_in2out_sm_unknown_proto (snat_main_t * sm,
 832                              vlib_buffer_t * b,
 833                              ip4_header_t * ip, u32 rx_fib_index)
 834 {
 835   clib_bihash_kv_8_8_t kv, value;
 836   snat_static_mapping_t *m;
 837   u32 old_addr, new_addr;
 838   ip_csum_t sum;
 839
 840   init_nat_k (&kv, ip->src_address, 0, rx_fib_index, 0);
 841   if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 842     return 1;
 843
 844   m = pool_elt_at_index (sm->static_mappings, value.value);
 845
 846   old_addr = ip->src_address.as_u32;
 847   new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 848   sum = ip->checksum;
 849   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 850   ip->checksum = ip_csum_fold (sum);
 851
 852
 853   /* Hairpinning */
 854   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 855     {
 856       vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 857       nat_hairpinning_sm_unknown_proto (sm, b, ip);
 858     }
 859
 860   return 0;
 861 }
 862
 863 static inline uword
 864 snat_in2out_node_fn_inline (vlib_main_t * vm,
 865                             vlib_node_runtime_t * node,
 866                             vlib_frame_t * frame, int is_slow_path,
 867                             int is_output_feature)
 868 {
 869   u32 n_left_from, *from;
 870   snat_main_t *sm = &snat_main;
 871   f64 now = vlib_time_now (vm);
 872   u32 thread_index = vm->thread_index;
 873
 874   from = vlib_frame_vector_args (frame);
 875   n_left_from = frame->n_vectors;
 876
 877   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 878   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 879   vlib_get_buffers (vm, from, b, n_left_from);
 880
 881   while (n_left_from >= 2)
 882     {
 883       vlib_buffer_t *b0, *b1;
 884       u32 next0, next1;
 885       u32 sw_if_index0, sw_if_index1;
 886       ip4_header_t *ip0, *ip1;
 887       ip_csum_t sum0, sum1;
 888       u32 new_addr0, old_addr0, new_addr1, old_addr1;
 889       u16 old_port0, new_port0, old_port1, new_port1;
 890       udp_header_t *udp0, *udp1;
 891       tcp_header_t *tcp0, *tcp1;
 892       icmp46_header_t *icmp0, *icmp1;
 893       u32 rx_fib_index0, rx_fib_index1;
 894       u32 proto0, proto1;
 895       snat_session_t *s0 = 0, *s1 = 0;
 896       clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
 897       u32 iph_offset0 = 0, iph_offset1 = 0;
 898
 899       b0 = *b;
 900       b++;
 901       b1 = *b;
 902       b++;
 903
 904       /* Prefetch next iteration. */
 905       if (PREDICT_TRUE (n_left_from >= 4))
 906         {
 907           vlib_buffer_t *p2, *p3;
 908
 909           p2 = *b;
 910           p3 = *(b + 1);
 911
 912           vlib_prefetch_buffer_header (p2, LOAD);
 913           vlib_prefetch_buffer_header (p3, LOAD);
 914
 915           CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
 916           CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, LOAD);
 917         }
 918
 919       if (is_output_feature)
 920         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 921
 922       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 923                               iph_offset0);
 924
 925       udp0 = ip4_next_header (ip0);
 926       tcp0 = (tcp_header_t *) udp0;
 927       icmp0 = (icmp46_header_t *) udp0;
 928
 929       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 930       rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 931                                sw_if_index0);
 932
 933       next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
 934
 935       if (PREDICT_FALSE (ip0->ttl == 1))
 936         {
 937           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 938           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 939                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
 940                                        0);
 941           next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
 942           goto trace00;
 943         }
 944
 945       proto0 = ip_proto_to_nat_proto (ip0->protocol);
 946
 947       /* Next configured feature, probably ip4-lookup */
 948       if (is_slow_path)
 949         {
 950           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 951             {
 952               if (nat_in2out_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 953                 {
 954                   next0 = SNAT_IN2OUT_NEXT_DROP;
 955                   b0->error =
 956                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
 957                 }
 958               vlib_increment_simple_counter (is_slow_path ? &sm->
 959                                              counters.slowpath.in2out.
 960                                              other : &sm->counters.fastpath.
 961                                              in2out.other, thread_index,
 962                                              sw_if_index0, 1);
 963               goto trace00;
 964             }
 965
 966           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 967             {
 968               next0 = icmp_in2out_slow_path
 969                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
 970                  node, next0, now, thread_index, &s0);
 971               vlib_increment_simple_counter (is_slow_path ? &sm->
 972                                              counters.slowpath.in2out.
 973                                              icmp : &sm->counters.fastpath.
 974                                              in2out.icmp, thread_index,
 975                                              sw_if_index0, 1);
 976               goto trace00;
 977             }
 978         }
 979       else
 980         {
 981           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 982             {
 983               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 984               goto trace00;
 985             }
 986
 987           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 988             {
 989               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 990               goto trace00;
 991             }
 992         }
 993
 994       init_nat_k (&kv0, ip0->src_address,
 995                   vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
 996                   proto0);
 997       if (PREDICT_FALSE
 998           (clib_bihash_search_8_8
 999            (&sm->per_thread_data[thread_index].in2out, &kv0, &value0) != 0))
1000         {
1001           if (is_slow_path)
1002             {
1003               if (is_output_feature)
1004                 {
1005                   if (PREDICT_FALSE
1006                       (nat_not_translate_output_feature
1007                        (sm, ip0, proto0,
1008                         vnet_buffer (b0)->ip.reass.l4_src_port,
1009                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1010                         thread_index, sw_if_index0)))
1011                     goto trace00;
1012
1013                   /*
1014                    * Send DHCP packets to the ipv4 stack, or we won't
1015                    * be able to use dhcp client on the outside interface
1016                    */
1017                   if (PREDICT_FALSE
1018                       (proto0 == NAT_PROTOCOL_UDP
1019                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1020                            clib_host_to_net_u16
1021                            (UDP_DST_PORT_dhcp_to_server))
1022                        && ip0->dst_address.as_u32 == 0xffffffff))
1023                     goto trace00;
1024                 }
1025               else
1026                 {
1027                   if (PREDICT_FALSE
1028                       (snat_not_translate
1029                        (sm, node, sw_if_index0, ip0, proto0,
1030                         rx_fib_index0, thread_index)))
1031                     goto trace00;
1032                 }
1033
1034               next0 = slow_path (sm, b0, ip0,
1035                                  ip0->src_address,
1036                                  vnet_buffer (b0)->ip.reass.l4_src_port,
1037                                  rx_fib_index0,
1038                                  proto0, &s0, node, next0, thread_index, now);
1039               if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1040                 goto trace00;
1041
1042               if (PREDICT_FALSE (!s0))
1043                 goto trace00;
1044             }
1045           else
1046             {
1047               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1048               goto trace00;
1049             }
1050         }
1051       else
1052         s0 =
1053           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1054                              value0.value);
1055
1056       b0->flags |= VNET_BUFFER_F_IS_NATED;
1057
1058       old_addr0 = ip0->src_address.as_u32;
1059       ip0->src_address = s0->out2in.addr;
1060       new_addr0 = ip0->src_address.as_u32;
1061       if (!is_output_feature)
1062         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1063
1064       sum0 = ip0->checksum;
1065       sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1066                              ip4_header_t, src_address /* changed member */ );
1067       ip0->checksum = ip_csum_fold (sum0);
1068
1069
1070       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1071         {
1072           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1073             {
1074               old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1075               new_port0 = udp0->src_port = s0->out2in.port;
1076               sum0 = tcp0->checksum;
1077               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1078                                      ip4_header_t,
1079                                      dst_address /* changed member */ );
1080               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1081                                      ip4_header_t /* cheat */ ,
1082                                      length /* changed member */ );
1083               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1084               tcp0->checksum = ip_csum_fold (sum0);
1085             }
1086           vlib_increment_simple_counter (is_slow_path ? &sm->
1087                                          counters.slowpath.in2out.tcp : &sm->
1088                                          counters.fastpath.in2out.tcp,
1089                                          thread_index, sw_if_index0, 1);
1090         }
1091       else
1092         {
1093           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1094             {
1095               udp0->src_port = s0->out2in.port;
1096               if (PREDICT_FALSE (udp0->checksum))
1097                 {
1098                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1099                   new_port0 = udp0->src_port;
1100                   sum0 = udp0->checksum;
1101                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address  /* changed member */
1102                     );
1103                   sum0 =
1104                     ip_csum_update (sum0, old_port0, new_port0,
1105                                     ip4_header_t /* cheat */ ,
1106                                     length /* changed member */ );
1107                   udp0->checksum = ip_csum_fold (sum0);
1108                 }
1109             }
1110           vlib_increment_simple_counter (is_slow_path ? &sm->
1111                                          counters.slowpath.in2out.udp : &sm->
1112                                          counters.fastpath.in2out.udp,
1113                                          thread_index, sw_if_index0, 1);
1114         }
1115
1116       /* Accounting */
1117       nat44_session_update_counters (s0, now,
1118                                      vlib_buffer_length_in_chain (vm, b0),
1119                                      thread_index);
1120       /* Per-user LRU list maintenance */
1121       nat44_session_update_lru (sm, s0, thread_index);
1122     trace00:
1123
1124       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1125                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1126         {
1127           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
1128           t->is_slow_path = is_slow_path;
1129           t->sw_if_index = sw_if_index0;
1130           t->next_index = next0;
1131           t->session_index = ~0;
1132           if (s0)
1133             t->session_index =
1134               s0 - sm->per_thread_data[thread_index].sessions;
1135         }
1136
1137       if (next0 == SNAT_IN2OUT_NEXT_DROP)
1138         {
1139           vlib_increment_simple_counter (is_slow_path ? &sm->
1140                                          counters.slowpath.in2out.
1141                                          drops : &sm->counters.fastpath.
1142                                          in2out.drops, thread_index,
1143                                          sw_if_index0, 1);
1144         }
1145
1146       if (is_output_feature)
1147         iph_offset1 = vnet_buffer (b1)->ip.reass.save_rewrite_length;
1148
1149       ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1150                               iph_offset1);
1151
1152       udp1 = ip4_next_header (ip1);
1153       tcp1 = (tcp_header_t *) udp1;
1154       icmp1 = (icmp46_header_t *) udp1;
1155
1156       sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1157       rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1158                                sw_if_index1);
1159
1160       if (PREDICT_FALSE (ip1->ttl == 1))
1161         {
1162           vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1163           icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1164                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1165                                        0);
1166           next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1167           goto trace01;
1168         }
1169
1170       proto1 = ip_proto_to_nat_proto (ip1->protocol);
1171
1172       /* Next configured feature, probably ip4-lookup */
1173       if (is_slow_path)
1174         {
1175           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1176             {
1177               if (nat_in2out_sm_unknown_proto (sm, b1, ip1, rx_fib_index1))
1178                 {
1179                   next1 = SNAT_IN2OUT_NEXT_DROP;
1180                   b1->error =
1181                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1182                 }
1183               vlib_increment_simple_counter (is_slow_path ? &sm->
1184                                              counters.slowpath.in2out.
1185                                              other : &sm->counters.fastpath.
1186                                              in2out.other, thread_index,
1187                                              sw_if_index1, 1);
1188               goto trace01;
1189             }
1190
1191           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1192             {
1193               next1 = icmp_in2out_slow_path
1194                 (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1195                  next1, now, thread_index, &s1);
1196               vlib_increment_simple_counter (is_slow_path ? &sm->
1197                                              counters.slowpath.in2out.
1198                                              icmp : &sm->counters.fastpath.
1199                                              in2out.icmp, thread_index,
1200                                              sw_if_index1, 1);
1201               goto trace01;
1202             }
1203         }
1204       else
1205         {
1206           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1207             {
1208               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1209               goto trace01;
1210             }
1211
1212           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1213             {
1214               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1215               goto trace01;
1216             }
1217         }
1218
1219       init_nat_k (&kv1, ip1->src_address,
1220                   vnet_buffer (b1)->ip.reass.l4_src_port, rx_fib_index1,
1221                   proto1);
1222       if (PREDICT_FALSE
1223           (clib_bihash_search_8_8
1224            (&sm->per_thread_data[thread_index].in2out, &kv1, &value1) != 0))
1225         {
1226           if (is_slow_path)
1227             {
1228               if (is_output_feature)
1229                 {
1230                   if (PREDICT_FALSE
1231                       (nat_not_translate_output_feature
1232                        (sm, ip1, proto1,
1233                         vnet_buffer (b1)->ip.reass.l4_src_port,
1234                         vnet_buffer (b1)->ip.reass.l4_dst_port,
1235                         thread_index, sw_if_index1)))
1236                     goto trace01;
1237
1238                   /*
1239                    * Send DHCP packets to the ipv4 stack, or we won't
1240                    * be able to use dhcp client on the outside interface
1241                    */
1242                   if (PREDICT_FALSE
1243                       (proto1 == NAT_PROTOCOL_UDP
1244                        && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
1245                            clib_host_to_net_u16
1246                            (UDP_DST_PORT_dhcp_to_server))
1247                        && ip1->dst_address.as_u32 == 0xffffffff))
1248                     goto trace01;
1249                 }
1250               else
1251                 {
1252                   if (PREDICT_FALSE
1253                       (snat_not_translate
1254                        (sm, node, sw_if_index1, ip1, proto1,
1255                         rx_fib_index1, thread_index)))
1256                     goto trace01;
1257                 }
1258
1259               next1 =
1260                 slow_path (sm, b1, ip1, ip1->src_address,
1261                            vnet_buffer (b1)->ip.reass.l4_src_port,
1262                            rx_fib_index1, proto1, &s1, node, next1,
1263                            thread_index, now);
1264               if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1265                 goto trace01;
1266
1267               if (PREDICT_FALSE (!s1))
1268                 goto trace01;
1269             }
1270           else
1271             {
1272               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1273               goto trace01;
1274             }
1275         }
1276       else
1277         s1 =
1278           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1279                              value1.value);
1280
1281       b1->flags |= VNET_BUFFER_F_IS_NATED;
1282
1283       old_addr1 = ip1->src_address.as_u32;
1284       ip1->src_address = s1->out2in.addr;
1285       new_addr1 = ip1->src_address.as_u32;
1286       if (!is_output_feature)
1287         vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1288
1289       sum1 = ip1->checksum;
1290       sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1291                              ip4_header_t, src_address /* changed member */ );
1292       ip1->checksum = ip_csum_fold (sum1);
1293
1294       if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
1295         {
1296           if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
1297             {
1298               old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1299               new_port1 = udp1->src_port = s1->out2in.port;
1300               sum1 = tcp1->checksum;
1301               sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1302                                      ip4_header_t,
1303                                      dst_address /* changed member */ );
1304               sum1 = ip_csum_update (sum1, old_port1, new_port1,
1305                                      ip4_header_t /* cheat */ ,
1306                                      length /* changed member */ );
1307               mss_clamping (sm->mss_clamping, tcp1, &sum1);
1308               tcp1->checksum = ip_csum_fold (sum1);
1309             }
1310           vlib_increment_simple_counter (is_slow_path ? &sm->
1311                                          counters.slowpath.in2out.tcp : &sm->
1312                                          counters.fastpath.in2out.tcp,
1313                                          thread_index, sw_if_index1, 1);
1314         }
1315       else
1316         {
1317           if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
1318             {
1319               udp1->src_port = s1->out2in.port;
1320               if (PREDICT_FALSE (udp1->checksum))
1321                 {
1322                   old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1323                   new_port1 = udp1->src_port;
1324                   sum1 = udp1->checksum;
1325                   sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t, dst_address  /* changed member */
1326                     );
1327                   sum1 =
1328                     ip_csum_update (sum1, old_port1, new_port1,
1329                                     ip4_header_t /* cheat */ ,
1330                                     length /* changed member */ );
1331                   udp1->checksum = ip_csum_fold (sum1);
1332                 }
1333             }
1334           vlib_increment_simple_counter (is_slow_path ? &sm->
1335                                          counters.slowpath.in2out.udp : &sm->
1336                                          counters.fastpath.in2out.udp,
1337                                          thread_index, sw_if_index1, 1);
1338         }
1339
1340       /* Accounting */
1341       nat44_session_update_counters (s1, now,
1342                                      vlib_buffer_length_in_chain (vm, b1),
1343                                      thread_index);
1344       /* Per-user LRU list maintenance */
1345       nat44_session_update_lru (sm, s1, thread_index);
1346     trace01:
1347
1348       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1349                          && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1350         {
1351           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b1, sizeof (*t));
1352           t->sw_if_index = sw_if_index1;
1353           t->next_index = next1;
1354           t->session_index = ~0;
1355           if (s1)
1356             t->session_index =
1357               s1 - sm->per_thread_data[thread_index].sessions;
1358         }
1359
1360       if (next1 == SNAT_IN2OUT_NEXT_DROP)
1361         {
1362           vlib_increment_simple_counter (is_slow_path ? &sm->
1363                                          counters.slowpath.in2out.
1364                                          drops : &sm->counters.fastpath.
1365                                          in2out.drops, thread_index,
1366                                          sw_if_index1, 1);
1367         }
1368
1369       n_left_from -= 2;
1370       next[0] = next0;
1371       next[1] = next1;
1372       next += 2;
1373     }
1374
1375   while (n_left_from > 0)
1376     {
1377       vlib_buffer_t *b0;
1378       u32 next0;
1379       u32 sw_if_index0;
1380       ip4_header_t *ip0;
1381       ip_csum_t sum0;
1382       u32 new_addr0, old_addr0;
1383       u16 old_port0, new_port0;
1384       udp_header_t *udp0;
1385       tcp_header_t *tcp0;
1386       icmp46_header_t *icmp0;
1387       u32 rx_fib_index0;
1388       u32 proto0;
1389       snat_session_t *s0 = 0;
1390       clib_bihash_kv_8_8_t kv0, value0;
1391       u32 iph_offset0 = 0;
1392
1393       b0 = *b;
1394       b++;
1395       next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1396
1397       if (is_output_feature)
1398         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1399
1400       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1401                               iph_offset0);
1402
1403       udp0 = ip4_next_header (ip0);
1404       tcp0 = (tcp_header_t *) udp0;
1405       icmp0 = (icmp46_header_t *) udp0;
1406
1407       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1408       rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1409                                sw_if_index0);
1410
1411       if (PREDICT_FALSE (ip0->ttl == 1))
1412         {
1413           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1414           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1415                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1416                                        0);
1417           next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1418           goto trace0;
1419         }
1420
1421       proto0 = ip_proto_to_nat_proto (ip0->protocol);
1422
1423       /* Next configured feature, probably ip4-lookup */
1424       if (is_slow_path)
1425         {
1426           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1427             {
1428               if (nat_in2out_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
1429                 {
1430                   next0 = SNAT_IN2OUT_NEXT_DROP;
1431                   b0->error =
1432                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1433                 }
1434               vlib_increment_simple_counter (is_slow_path ? &sm->
1435                                              counters.slowpath.in2out.
1436                                              other : &sm->counters.fastpath.
1437                                              in2out.other, thread_index,
1438                                              sw_if_index0, 1);
1439               goto trace0;
1440             }
1441
1442           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1443             {
1444               next0 = icmp_in2out_slow_path
1445                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1446                  next0, now, thread_index, &s0);
1447               vlib_increment_simple_counter (is_slow_path ? &sm->
1448                                              counters.slowpath.in2out.
1449                                              icmp : &sm->counters.fastpath.
1450                                              in2out.icmp, thread_index,
1451                                              sw_if_index0, 1);
1452               goto trace0;
1453             }
1454         }
1455       else
1456         {
1457           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1458             {
1459               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1460               goto trace0;
1461             }
1462
1463           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1464             {
1465               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1466               goto trace0;
1467             }
1468         }
1469
1470       init_nat_k (&kv0, ip0->src_address,
1471                   vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
1472                   proto0);
1473
1474       if (clib_bihash_search_8_8
1475           (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1476         {
1477           if (is_slow_path)
1478             {
1479               if (is_output_feature)
1480                 {
1481                   if (PREDICT_FALSE
1482                       (nat_not_translate_output_feature
1483                        (sm, ip0, proto0,
1484                         vnet_buffer (b0)->ip.reass.l4_src_port,
1485                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1486                         thread_index, sw_if_index0)))
1487                     goto trace0;
1488
1489                   /*
1490                    * Send DHCP packets to the ipv4 stack, or we won't
1491                    * be able to use dhcp client on the outside interface
1492                    */
1493                   if (PREDICT_FALSE
1494                       (proto0 == NAT_PROTOCOL_UDP
1495                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1496                            clib_host_to_net_u16
1497                            (UDP_DST_PORT_dhcp_to_server))
1498                        && ip0->dst_address.as_u32 == 0xffffffff))
1499                     goto trace0;
1500                 }
1501               else
1502                 {
1503                   if (PREDICT_FALSE
1504                       (snat_not_translate
1505                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1506                         thread_index)))
1507                     goto trace0;
1508                 }
1509
1510               next0 =
1511                 slow_path (sm, b0, ip0, ip0->src_address,
1512                            vnet_buffer (b0)->ip.reass.l4_src_port,
1513                            rx_fib_index0, proto0, &s0, node, next0,
1514                            thread_index, now);
1515
1516               if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1517                 goto trace0;
1518
1519               if (PREDICT_FALSE (!s0))
1520                 goto trace0;
1521             }
1522           else
1523             {
1524               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1525               goto trace0;
1526             }
1527         }
1528       else
1529         s0 =
1530           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1531                              value0.value);
1532
1533       b0->flags |= VNET_BUFFER_F_IS_NATED;
1534
1535       old_addr0 = ip0->src_address.as_u32;
1536       ip0->src_address = s0->out2in.addr;
1537       new_addr0 = ip0->src_address.as_u32;
1538       if (!is_output_feature)
1539         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1540
1541       sum0 = ip0->checksum;
1542       sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1543                              ip4_header_t, src_address /* changed member */ );
1544       ip0->checksum = ip_csum_fold (sum0);
1545
1546       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1547         {
1548           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1549             {
1550               old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1551               new_port0 = udp0->src_port = s0->out2in.port;
1552               sum0 = tcp0->checksum;
1553               sum0 =
1554                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1555                                 dst_address /* changed member */ );
1556               sum0 =
1557                 ip_csum_update (sum0, old_port0, new_port0,
1558                                 ip4_header_t /* cheat */ ,
1559                                 length /* changed member */ );
1560               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1561               tcp0->checksum = ip_csum_fold (sum0);
1562             }
1563           vlib_increment_simple_counter (is_slow_path ? &sm->
1564                                          counters.slowpath.in2out.tcp : &sm->
1565                                          counters.fastpath.in2out.tcp,
1566                                          thread_index, sw_if_index0, 1);
1567         }
1568       else
1569         {
1570           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1571             {
1572               udp0->src_port = s0->out2in.port;
1573               if (PREDICT_FALSE (udp0->checksum))
1574                 {
1575                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1576                   new_port0 = udp0->src_port;
1577                   sum0 = udp0->checksum;
1578                   sum0 =
1579                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1580                                     dst_address /* changed member */ );
1581                   sum0 =
1582                     ip_csum_update (sum0, old_port0, new_port0,
1583                                     ip4_header_t /* cheat */ ,
1584                                     length /* changed member */ );
1585                   udp0->checksum = ip_csum_fold (sum0);
1586                 }
1587             }
1588           vlib_increment_simple_counter (is_slow_path ? &sm->
1589                                          counters.slowpath.in2out.udp : &sm->
1590                                          counters.fastpath.in2out.udp,
1591                                          thread_index, sw_if_index0, 1);
1592         }
1593
1594       /* Accounting */
1595       nat44_session_update_counters (s0, now,
1596                                      vlib_buffer_length_in_chain (vm, b0),
1597                                      thread_index);
1598       /* Per-user LRU list maintenance */
1599       nat44_session_update_lru (sm, s0, thread_index);
1600
1601     trace0:
1602       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1603                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1604         {
1605           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
1606           t->is_slow_path = is_slow_path;
1607           t->sw_if_index = sw_if_index0;
1608           t->next_index = next0;
1609           t->session_index = ~0;
1610           if (s0)
1611             t->session_index =
1612               s0 - sm->per_thread_data[thread_index].sessions;
1613         }
1614
1615       if (next0 == SNAT_IN2OUT_NEXT_DROP)
1616         {
1617           vlib_increment_simple_counter (is_slow_path ? &sm->
1618                                          counters.slowpath.in2out.
1619                                          drops : &sm->counters.fastpath.
1620                                          in2out.drops, thread_index,
1621                                          sw_if_index0, 1);
1622         }
1623
1624       n_left_from--;
1625       next[0] = next0;
1626       next++;
1627     }
1628
1629   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1630                                frame->n_vectors);
1631   return frame->n_vectors;
1632 }
1633
1634 VLIB_NODE_FN (snat_in2out_node) (vlib_main_t * vm,
1635                                  vlib_node_runtime_t * node,
1636                                  vlib_frame_t * frame)
1637 {
1638   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1639                                      0);
1640 }
1641
1642 /* *INDENT-OFF* */
1643 VLIB_REGISTER_NODE (snat_in2out_node) = {
1644   .name = "nat44-in2out",
1645   .vector_size = sizeof (u32),
1646   .format_trace = format_snat_in2out_trace,
1647   .type = VLIB_NODE_TYPE_INTERNAL,
1648
1649   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1650   .error_strings = snat_in2out_error_strings,
1651
1652   .runtime_data_bytes = sizeof (snat_runtime_t),
1653
1654   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1655
1656   /* edit / add dispositions here */
1657   .next_nodes = {
1658     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1659     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1660     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1661     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1662   },
1663 };
1664 /* *INDENT-ON* */
1665
1666 VLIB_NODE_FN (snat_in2out_output_node) (vlib_main_t * vm,
1667                                         vlib_node_runtime_t * node,
1668                                         vlib_frame_t * frame)
1669 {
1670   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1671                                      1);
1672 }
1673
1674 /* *INDENT-OFF* */
1675 VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1676   .name = "nat44-in2out-output",
1677   .vector_size = sizeof (u32),
1678   .format_trace = format_snat_in2out_trace,
1679   .type = VLIB_NODE_TYPE_INTERNAL,
1680
1681   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1682   .error_strings = snat_in2out_error_strings,
1683
1684   .runtime_data_bytes = sizeof (snat_runtime_t),
1685
1686   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1687
1688   /* edit / add dispositions here */
1689   .next_nodes = {
1690     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1691     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1692     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1693     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1694   },
1695 };
1696 /* *INDENT-ON* */
1697
1698 VLIB_NODE_FN (snat_in2out_slowpath_node) (vlib_main_t * vm,
1699                                           vlib_node_runtime_t * node,
1700                                           vlib_frame_t * frame)
1701 {
1702   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1703                                      0);
1704 }
1705
1706 /* *INDENT-OFF* */
1707 VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1708   .name = "nat44-in2out-slowpath",
1709   .vector_size = sizeof (u32),
1710   .format_trace = format_snat_in2out_trace,
1711   .type = VLIB_NODE_TYPE_INTERNAL,
1712
1713   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1714   .error_strings = snat_in2out_error_strings,
1715
1716   .runtime_data_bytes = sizeof (snat_runtime_t),
1717
1718   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1719
1720   /* edit / add dispositions here */
1721   .next_nodes = {
1722     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1723     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1724     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1725     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1726   },
1727 };
1728 /* *INDENT-ON* */
1729
1730 VLIB_NODE_FN (snat_in2out_output_slowpath_node) (vlib_main_t * vm,
1731                                                  vlib_node_runtime_t * node,
1732                                                  vlib_frame_t * frame)
1733 {
1734   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1735                                      1);
1736 }
1737
1738 /* *INDENT-OFF* */
1739 VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1740   .name = "nat44-in2out-output-slowpath",
1741   .vector_size = sizeof (u32),
1742   .format_trace = format_snat_in2out_trace,
1743   .type = VLIB_NODE_TYPE_INTERNAL,
1744
1745   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1746   .error_strings = snat_in2out_error_strings,
1747
1748   .runtime_data_bytes = sizeof (snat_runtime_t),
1749
1750   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1751
1752   /* edit / add dispositions here */
1753   .next_nodes = {
1754     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1755     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1756     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1757     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1758   },
1759 };
1760 /* *INDENT-ON* */
1761
1762 VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
1763                                       vlib_node_runtime_t * node,
1764                                       vlib_frame_t * frame)
1765 {
1766   u32 n_left_from, *from, *to_next;
1767   snat_in2out_next_t next_index;
1768   snat_main_t *sm = &snat_main;
1769   int is_hairpinning = 0;
1770
1771   from = vlib_frame_vector_args (frame);
1772   n_left_from = frame->n_vectors;
1773   next_index = node->cached_next_index;
1774
1775   while (n_left_from > 0)
1776     {
1777       u32 n_left_to_next;
1778
1779       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1780
1781       while (n_left_from > 0 && n_left_to_next > 0)
1782         {
1783           u32 bi0;
1784           vlib_buffer_t *b0;
1785           u32 next0;
1786           u32 sw_if_index0;
1787           ip4_header_t *ip0;
1788           ip_csum_t sum0;
1789           u32 new_addr0, old_addr0;
1790           u16 old_port0, new_port0;
1791           udp_header_t *udp0;
1792           tcp_header_t *tcp0;
1793           icmp46_header_t *icmp0;
1794           u32 proto0;
1795           u32 rx_fib_index0;
1796           ip4_address_t sm0_addr;
1797           u16 sm0_port;
1798           u32 sm0_fib_index;
1799
1800
1801           /* speculatively enqueue b0 to the current next frame */
1802           bi0 = from[0];
1803           to_next[0] = bi0;
1804           from += 1;
1805           to_next += 1;
1806           n_left_from -= 1;
1807           n_left_to_next -= 1;
1808
1809           b0 = vlib_get_buffer (vm, bi0);
1810           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1811
1812           ip0 = vlib_buffer_get_current (b0);
1813           udp0 = ip4_next_header (ip0);
1814           tcp0 = (tcp_header_t *) udp0;
1815           icmp0 = (icmp46_header_t *) udp0;
1816
1817           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1818           rx_fib_index0 =
1819             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
1820
1821           if (PREDICT_FALSE (ip0->ttl == 1))
1822             {
1823               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1824               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1825                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1826                                            0);
1827               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1828               goto trace0;
1829             }
1830
1831           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1832
1833           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1834             goto trace0;
1835
1836           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1837             {
1838               next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
1839                                    rx_fib_index0, node, next0, ~0, 0, 0);
1840               goto trace0;
1841             }
1842
1843           if (snat_static_mapping_match
1844               (sm, ip0->src_address, udp0->src_port, rx_fib_index0, proto0,
1845                &sm0_addr, &sm0_port, &sm0_fib_index, 0, 0, 0, 0, 0, 0, 0))
1846             {
1847               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
1848               next0 = SNAT_IN2OUT_NEXT_DROP;
1849               goto trace0;
1850             }
1851
1852           new_addr0 = sm0_addr.as_u32;
1853           new_port0 = sm0_port;
1854           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0_fib_index;
1855           old_addr0 = ip0->src_address.as_u32;
1856           ip0->src_address.as_u32 = new_addr0;
1857
1858           sum0 = ip0->checksum;
1859           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1860                                  ip4_header_t,
1861                                  src_address /* changed member */ );
1862           ip0->checksum = ip_csum_fold (sum0);
1863
1864           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
1865             {
1866               old_port0 = udp0->src_port;
1867               udp0->src_port = new_port0;
1868
1869               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1870                 {
1871                   sum0 = tcp0->checksum;
1872                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1873                                          ip4_header_t,
1874                                          dst_address /* changed member */ );
1875                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1876                                          ip4_header_t /* cheat */ ,
1877                                          length /* changed member */ );
1878                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1879                   tcp0->checksum = ip_csum_fold (sum0);
1880                 }
1881               else if (udp0->checksum)
1882                 {
1883                   sum0 = udp0->checksum;
1884                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1885                                          ip4_header_t,
1886                                          dst_address /* changed member */ );
1887                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1888                                          ip4_header_t /* cheat */ ,
1889                                          length /* changed member */ );
1890                   udp0->checksum = ip_csum_fold (sum0);
1891                 }
1892             }
1893           else
1894             {
1895               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1896                 {
1897                   sum0 = tcp0->checksum;
1898                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1899                                          ip4_header_t,
1900                                          dst_address /* changed member */ );
1901                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1902                   tcp0->checksum = ip_csum_fold (sum0);
1903                 }
1904               else if (udp0->checksum)
1905                 {
1906                   sum0 = udp0->checksum;
1907                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1908                                          ip4_header_t,
1909                                          dst_address /* changed member */ );
1910                   udp0->checksum = ip_csum_fold (sum0);
1911                 }
1912             }
1913
1914           /* Hairpinning */
1915           snat_hairpinning (vm, node, sm, b0, ip0, udp0, tcp0, proto0, 0,
1916                             0 /* do_trace */ );
1917           is_hairpinning = 1;
1918
1919         trace0:
1920           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1921                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1922             {
1923               snat_in2out_trace_t *t =
1924                 vlib_add_trace (vm, node, b0, sizeof (*t));
1925               t->sw_if_index = sw_if_index0;
1926               t->next_index = next0;
1927               t->is_hairpinning = is_hairpinning;
1928             }
1929
1930           if (next0 != SNAT_IN2OUT_NEXT_DROP)
1931             {
1932
1933               vlib_increment_simple_counter (&sm->counters.fastpath.
1934                                              in2out.other, sw_if_index0,
1935                                              vm->thread_index, 1);
1936             }
1937
1938           /* verify speculative enqueue, maybe switch current next frame */
1939           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1940                                            to_next, n_left_to_next,
1941                                            bi0, next0);
1942         }
1943
1944       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1945     }
1946
1947   return frame->n_vectors;
1948 }
1949
1950
1951 /* *INDENT-OFF* */
1952 VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
1953   .name = "nat44-in2out-fast",
1954   .vector_size = sizeof (u32),
1955   .format_trace = format_snat_in2out_fast_trace,
1956   .type = VLIB_NODE_TYPE_INTERNAL,
1957
1958   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1959   .error_strings = snat_in2out_error_strings,
1960
1961   .runtime_data_bytes = sizeof (snat_runtime_t),
1962
1963   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1964
1965   /* edit / add dispositions here */
1966   .next_nodes = {
1967     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1968     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1969     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1970     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1971   },
1972 };
1973 /* *INDENT-ON* */
1974
1975 /*
1976  * fd.io coding-style-patch-verification: ON
1977  *
1978  * Local Variables:
1979  * eval: (c-set-style "gnu")
1980  * End:
1981  */