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))
 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))
 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))
 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 (sm->deterministic ||
 793           0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
 794                                       sm->endpoint_dependent))
 795         vnet_buffer (b0)->sw_if_index[VLIB_TX] = fib_index;
 796     }
 797
 798 out:
 799   return next0;
 800 }
 801 #endif
 802
 803 static inline u32
 804 icmp_in2out_slow_path (snat_main_t * sm,
 805                        vlib_buffer_t * b0,
 806                        ip4_header_t * ip0,
 807                        icmp46_header_t * icmp0,
 808                        u32 sw_if_index0,
 809                        u32 rx_fib_index0,
 810                        vlib_node_runtime_t * node,
 811                        u32 next0,
 812                        f64 now, u32 thread_index, snat_session_t ** p_s0)
 813 {
 814   vlib_main_t *vm = vlib_get_main ();
 815
 816   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 817                        next0, thread_index, p_s0, 0);
 818   snat_session_t *s0 = *p_s0;
 819   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
 820     {
 821       /* Accounting */
 822       nat44_session_update_counters (s0, now,
 823                                      vlib_buffer_length_in_chain
 824                                      (vm, b0), thread_index);
 825       /* Per-user LRU list maintenance */
 826       nat44_session_update_lru (sm, s0, thread_index);
 827     }
 828   return next0;
 829 }
 830
 831 static int
 832 nat_in2out_sm_unknown_proto (snat_main_t * sm,
 833                              vlib_buffer_t * b,
 834                              ip4_header_t * ip, u32 rx_fib_index)
 835 {
 836   clib_bihash_kv_8_8_t kv, value;
 837   snat_static_mapping_t *m;
 838   u32 old_addr, new_addr;
 839   ip_csum_t sum;
 840
 841   init_nat_k (&kv, ip->src_address, 0, rx_fib_index, 0);
 842   if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 843     return 1;
 844
 845   m = pool_elt_at_index (sm->static_mappings, value.value);
 846
 847   old_addr = ip->src_address.as_u32;
 848   new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 849   sum = ip->checksum;
 850   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 851   ip->checksum = ip_csum_fold (sum);
 852
 853
 854   /* Hairpinning */
 855   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 856     {
 857       vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 858       nat_hairpinning_sm_unknown_proto (sm, b, ip);
 859     }
 860
 861   return 0;
 862 }
 863
 864 static inline uword
 865 snat_in2out_node_fn_inline (vlib_main_t * vm,
 866                             vlib_node_runtime_t * node,
 867                             vlib_frame_t * frame, int is_slow_path,
 868                             int is_output_feature)
 869 {
 870   u32 n_left_from, *from;
 871   snat_main_t *sm = &snat_main;
 872   f64 now = vlib_time_now (vm);
 873   u32 thread_index = vm->thread_index;
 874
 875   from = vlib_frame_vector_args (frame);
 876   n_left_from = frame->n_vectors;
 877
 878   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 879   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 880   vlib_get_buffers (vm, from, b, n_left_from);
 881
 882   while (n_left_from >= 2)
 883     {
 884       vlib_buffer_t *b0, *b1;
 885       u32 next0, next1;
 886       u32 sw_if_index0, sw_if_index1;
 887       ip4_header_t *ip0, *ip1;
 888       ip_csum_t sum0, sum1;
 889       u32 new_addr0, old_addr0, new_addr1, old_addr1;
 890       u16 old_port0, new_port0, old_port1, new_port1;
 891       udp_header_t *udp0, *udp1;
 892       tcp_header_t *tcp0, *tcp1;
 893       icmp46_header_t *icmp0, *icmp1;
 894       u32 rx_fib_index0, rx_fib_index1;
 895       u32 proto0, proto1;
 896       snat_session_t *s0 = 0, *s1 = 0;
 897       clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
 898       u32 iph_offset0 = 0, iph_offset1 = 0;
 899
 900       b0 = *b;
 901       b++;
 902       b1 = *b;
 903       b++;
 904
 905       /* Prefetch next iteration. */
 906       if (PREDICT_TRUE (n_left_from >= 4))
 907         {
 908           vlib_buffer_t *p2, *p3;
 909
 910           p2 = *b;
 911           p3 = *(b + 1);
 912
 913           vlib_prefetch_buffer_header (p2, LOAD);
 914           vlib_prefetch_buffer_header (p3, LOAD);
 915
 916           CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
 917           CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, LOAD);
 918         }
 919
 920       if (is_output_feature)
 921         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 922
 923       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 924                               iph_offset0);
 925
 926       udp0 = ip4_next_header (ip0);
 927       tcp0 = (tcp_header_t *) udp0;
 928       icmp0 = (icmp46_header_t *) udp0;
 929
 930       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 931       rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 932                                sw_if_index0);
 933
 934       next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
 935
 936       if (PREDICT_FALSE (ip0->ttl == 1))
 937         {
 938           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 939           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 940                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
 941                                        0);
 942           next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
 943           goto trace00;
 944         }
 945
 946       proto0 = ip_proto_to_nat_proto (ip0->protocol);
 947
 948       /* Next configured feature, probably ip4-lookup */
 949       if (is_slow_path)
 950         {
 951           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 952             {
 953               if (nat_in2out_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 954                 {
 955                   next0 = SNAT_IN2OUT_NEXT_DROP;
 956                   b0->error =
 957                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
 958                 }
 959               vlib_increment_simple_counter (is_slow_path ? &sm->
 960                                              counters.slowpath.in2out.
 961                                              other : &sm->counters.fastpath.
 962                                              in2out.other, thread_index,
 963                                              sw_if_index0, 1);
 964               goto trace00;
 965             }
 966
 967           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 968             {
 969               next0 = icmp_in2out_slow_path
 970                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
 971                  node, next0, now, thread_index, &s0);
 972               vlib_increment_simple_counter (is_slow_path ? &sm->
 973                                              counters.slowpath.in2out.
 974                                              icmp : &sm->counters.fastpath.
 975                                              in2out.icmp, thread_index,
 976                                              sw_if_index0, 1);
 977               goto trace00;
 978             }
 979         }
 980       else
 981         {
 982           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 983             {
 984               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 985               goto trace00;
 986             }
 987
 988           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 989             {
 990               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 991               goto trace00;
 992             }
 993         }
 994
 995       init_nat_k (&kv0, ip0->src_address,
 996                   vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
 997                   proto0);
 998       if (PREDICT_FALSE
 999           (clib_bihash_search_8_8
1000            (&sm->per_thread_data[thread_index].in2out, &kv0, &value0) != 0))
1001         {
1002           if (is_slow_path)
1003             {
1004               if (is_output_feature)
1005                 {
1006                   if (PREDICT_FALSE
1007                       (nat_not_translate_output_feature
1008                        (sm, ip0, proto0,
1009                         vnet_buffer (b0)->ip.reass.l4_src_port,
1010                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1011                         thread_index, sw_if_index0)))
1012                     goto trace00;
1013
1014                   /*
1015                    * Send DHCP packets to the ipv4 stack, or we won't
1016                    * be able to use dhcp client on the outside interface
1017                    */
1018                   if (PREDICT_FALSE
1019                       (proto0 == NAT_PROTOCOL_UDP
1020                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1021                            clib_host_to_net_u16
1022                            (UDP_DST_PORT_dhcp_to_server))
1023                        && ip0->dst_address.as_u32 == 0xffffffff))
1024                     goto trace00;
1025                 }
1026               else
1027                 {
1028                   if (PREDICT_FALSE
1029                       (snat_not_translate
1030                        (sm, node, sw_if_index0, ip0, proto0,
1031                         rx_fib_index0, thread_index)))
1032                     goto trace00;
1033                 }
1034
1035               next0 = slow_path (sm, b0, ip0,
1036                                  ip0->src_address,
1037                                  vnet_buffer (b0)->ip.reass.l4_src_port,
1038                                  rx_fib_index0,
1039                                  proto0, &s0, node, next0, thread_index, now);
1040               if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1041                 goto trace00;
1042
1043               if (PREDICT_FALSE (!s0))
1044                 goto trace00;
1045             }
1046           else
1047             {
1048               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1049               goto trace00;
1050             }
1051         }
1052       else
1053         s0 =
1054           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1055                              value0.value);
1056
1057       b0->flags |= VNET_BUFFER_F_IS_NATED;
1058
1059       old_addr0 = ip0->src_address.as_u32;
1060       ip0->src_address = s0->out2in.addr;
1061       new_addr0 = ip0->src_address.as_u32;
1062       if (!is_output_feature)
1063         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1064
1065       sum0 = ip0->checksum;
1066       sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1067                              ip4_header_t, src_address /* changed member */ );
1068       ip0->checksum = ip_csum_fold (sum0);
1069
1070
1071       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1072         {
1073           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1074             {
1075               old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1076               new_port0 = udp0->src_port = s0->out2in.port;
1077               sum0 = tcp0->checksum;
1078               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1079                                      ip4_header_t,
1080                                      dst_address /* changed member */ );
1081               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1082                                      ip4_header_t /* cheat */ ,
1083                                      length /* changed member */ );
1084               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1085               tcp0->checksum = ip_csum_fold (sum0);
1086             }
1087           vlib_increment_simple_counter (is_slow_path ? &sm->
1088                                          counters.slowpath.in2out.tcp : &sm->
1089                                          counters.fastpath.in2out.tcp,
1090                                          thread_index, sw_if_index0, 1);
1091         }
1092       else
1093         {
1094           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1095             {
1096               udp0->src_port = s0->out2in.port;
1097               if (PREDICT_FALSE (udp0->checksum))
1098                 {
1099                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1100                   new_port0 = udp0->src_port;
1101                   sum0 = udp0->checksum;
1102                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address  /* changed member */
1103                     );
1104                   sum0 =
1105                     ip_csum_update (sum0, old_port0, new_port0,
1106                                     ip4_header_t /* cheat */ ,
1107                                     length /* changed member */ );
1108                   udp0->checksum = ip_csum_fold (sum0);
1109                 }
1110             }
1111           vlib_increment_simple_counter (is_slow_path ? &sm->
1112                                          counters.slowpath.in2out.udp : &sm->
1113                                          counters.fastpath.in2out.udp,
1114                                          thread_index, sw_if_index0, 1);
1115         }
1116
1117       /* Accounting */
1118       nat44_session_update_counters (s0, now,
1119                                      vlib_buffer_length_in_chain (vm, b0),
1120                                      thread_index);
1121       /* Per-user LRU list maintenance */
1122       nat44_session_update_lru (sm, s0, thread_index);
1123     trace00:
1124
1125       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1126                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1127         {
1128           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
1129           t->is_slow_path = is_slow_path;
1130           t->sw_if_index = sw_if_index0;
1131           t->next_index = next0;
1132           t->session_index = ~0;
1133           if (s0)
1134             t->session_index =
1135               s0 - sm->per_thread_data[thread_index].sessions;
1136         }
1137
1138       if (next0 == SNAT_IN2OUT_NEXT_DROP)
1139         {
1140           vlib_increment_simple_counter (is_slow_path ? &sm->
1141                                          counters.slowpath.in2out.
1142                                          drops : &sm->counters.fastpath.
1143                                          in2out.drops, thread_index,
1144                                          sw_if_index0, 1);
1145         }
1146
1147       if (is_output_feature)
1148         iph_offset1 = vnet_buffer (b1)->ip.reass.save_rewrite_length;
1149
1150       ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1151                               iph_offset1);
1152
1153       udp1 = ip4_next_header (ip1);
1154       tcp1 = (tcp_header_t *) udp1;
1155       icmp1 = (icmp46_header_t *) udp1;
1156
1157       sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1158       rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1159                                sw_if_index1);
1160
1161       if (PREDICT_FALSE (ip1->ttl == 1))
1162         {
1163           vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1164           icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1165                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1166                                        0);
1167           next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1168           goto trace01;
1169         }
1170
1171       proto1 = ip_proto_to_nat_proto (ip1->protocol);
1172
1173       /* Next configured feature, probably ip4-lookup */
1174       if (is_slow_path)
1175         {
1176           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1177             {
1178               if (nat_in2out_sm_unknown_proto (sm, b1, ip1, rx_fib_index1))
1179                 {
1180                   next1 = SNAT_IN2OUT_NEXT_DROP;
1181                   b1->error =
1182                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1183                 }
1184               vlib_increment_simple_counter (is_slow_path ? &sm->
1185                                              counters.slowpath.in2out.
1186                                              other : &sm->counters.fastpath.
1187                                              in2out.other, thread_index,
1188                                              sw_if_index1, 1);
1189               goto trace01;
1190             }
1191
1192           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1193             {
1194               next1 = icmp_in2out_slow_path
1195                 (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1196                  next1, now, thread_index, &s1);
1197               vlib_increment_simple_counter (is_slow_path ? &sm->
1198                                              counters.slowpath.in2out.
1199                                              icmp : &sm->counters.fastpath.
1200                                              in2out.icmp, thread_index,
1201                                              sw_if_index1, 1);
1202               goto trace01;
1203             }
1204         }
1205       else
1206         {
1207           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1208             {
1209               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1210               goto trace01;
1211             }
1212
1213           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1214             {
1215               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1216               goto trace01;
1217             }
1218         }
1219
1220       init_nat_k (&kv1, ip1->src_address,
1221                   vnet_buffer (b1)->ip.reass.l4_src_port, rx_fib_index1,
1222                   proto1);
1223       if (PREDICT_FALSE
1224           (clib_bihash_search_8_8
1225            (&sm->per_thread_data[thread_index].in2out, &kv1, &value1) != 0))
1226         {
1227           if (is_slow_path)
1228             {
1229               if (is_output_feature)
1230                 {
1231                   if (PREDICT_FALSE
1232                       (nat_not_translate_output_feature
1233                        (sm, ip1, proto1,
1234                         vnet_buffer (b1)->ip.reass.l4_src_port,
1235                         vnet_buffer (b1)->ip.reass.l4_dst_port,
1236                         thread_index, sw_if_index1)))
1237                     goto trace01;
1238
1239                   /*
1240                    * Send DHCP packets to the ipv4 stack, or we won't
1241                    * be able to use dhcp client on the outside interface
1242                    */
1243                   if (PREDICT_FALSE
1244                       (proto1 == NAT_PROTOCOL_UDP
1245                        && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
1246                            clib_host_to_net_u16
1247                            (UDP_DST_PORT_dhcp_to_server))
1248                        && ip1->dst_address.as_u32 == 0xffffffff))
1249                     goto trace01;
1250                 }
1251               else
1252                 {
1253                   if (PREDICT_FALSE
1254                       (snat_not_translate
1255                        (sm, node, sw_if_index1, ip1, proto1,
1256                         rx_fib_index1, thread_index)))
1257                     goto trace01;
1258                 }
1259
1260               next1 =
1261                 slow_path (sm, b1, ip1, ip1->src_address,
1262                            vnet_buffer (b1)->ip.reass.l4_src_port,
1263                            rx_fib_index1, proto1, &s1, node, next1,
1264                            thread_index, now);
1265               if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1266                 goto trace01;
1267
1268               if (PREDICT_FALSE (!s1))
1269                 goto trace01;
1270             }
1271           else
1272             {
1273               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1274               goto trace01;
1275             }
1276         }
1277       else
1278         s1 =
1279           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1280                              value1.value);
1281
1282       b1->flags |= VNET_BUFFER_F_IS_NATED;
1283
1284       old_addr1 = ip1->src_address.as_u32;
1285       ip1->src_address = s1->out2in.addr;
1286       new_addr1 = ip1->src_address.as_u32;
1287       if (!is_output_feature)
1288         vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1289
1290       sum1 = ip1->checksum;
1291       sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1292                              ip4_header_t, src_address /* changed member */ );
1293       ip1->checksum = ip_csum_fold (sum1);
1294
1295       if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
1296         {
1297           if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
1298             {
1299               old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1300               new_port1 = udp1->src_port = s1->out2in.port;
1301               sum1 = tcp1->checksum;
1302               sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1303                                      ip4_header_t,
1304                                      dst_address /* changed member */ );
1305               sum1 = ip_csum_update (sum1, old_port1, new_port1,
1306                                      ip4_header_t /* cheat */ ,
1307                                      length /* changed member */ );
1308               mss_clamping (sm->mss_clamping, tcp1, &sum1);
1309               tcp1->checksum = ip_csum_fold (sum1);
1310             }
1311           vlib_increment_simple_counter (is_slow_path ? &sm->
1312                                          counters.slowpath.in2out.tcp : &sm->
1313                                          counters.fastpath.in2out.tcp,
1314                                          thread_index, sw_if_index1, 1);
1315         }
1316       else
1317         {
1318           if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
1319             {
1320               udp1->src_port = s1->out2in.port;
1321               if (PREDICT_FALSE (udp1->checksum))
1322                 {
1323                   old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1324                   new_port1 = udp1->src_port;
1325                   sum1 = udp1->checksum;
1326                   sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t, dst_address  /* changed member */
1327                     );
1328                   sum1 =
1329                     ip_csum_update (sum1, old_port1, new_port1,
1330                                     ip4_header_t /* cheat */ ,
1331                                     length /* changed member */ );
1332                   udp1->checksum = ip_csum_fold (sum1);
1333                 }
1334             }
1335           vlib_increment_simple_counter (is_slow_path ? &sm->
1336                                          counters.slowpath.in2out.udp : &sm->
1337                                          counters.fastpath.in2out.udp,
1338                                          thread_index, sw_if_index1, 1);
1339         }
1340
1341       /* Accounting */
1342       nat44_session_update_counters (s1, now,
1343                                      vlib_buffer_length_in_chain (vm, b1),
1344                                      thread_index);
1345       /* Per-user LRU list maintenance */
1346       nat44_session_update_lru (sm, s1, thread_index);
1347     trace01:
1348
1349       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1350                          && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1351         {
1352           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b1, sizeof (*t));
1353           t->sw_if_index = sw_if_index1;
1354           t->next_index = next1;
1355           t->session_index = ~0;
1356           if (s1)
1357             t->session_index =
1358               s1 - sm->per_thread_data[thread_index].sessions;
1359         }
1360
1361       if (next1 == SNAT_IN2OUT_NEXT_DROP)
1362         {
1363           vlib_increment_simple_counter (is_slow_path ? &sm->
1364                                          counters.slowpath.in2out.
1365                                          drops : &sm->counters.fastpath.
1366                                          in2out.drops, thread_index,
1367                                          sw_if_index1, 1);
1368         }
1369
1370       n_left_from -= 2;
1371       next[0] = next0;
1372       next[1] = next1;
1373       next += 2;
1374     }
1375
1376   while (n_left_from > 0)
1377     {
1378       vlib_buffer_t *b0;
1379       u32 next0;
1380       u32 sw_if_index0;
1381       ip4_header_t *ip0;
1382       ip_csum_t sum0;
1383       u32 new_addr0, old_addr0;
1384       u16 old_port0, new_port0;
1385       udp_header_t *udp0;
1386       tcp_header_t *tcp0;
1387       icmp46_header_t *icmp0;
1388       u32 rx_fib_index0;
1389       u32 proto0;
1390       snat_session_t *s0 = 0;
1391       clib_bihash_kv_8_8_t kv0, value0;
1392       u32 iph_offset0 = 0;
1393
1394       b0 = *b;
1395       b++;
1396       next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1397
1398       if (is_output_feature)
1399         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1400
1401       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1402                               iph_offset0);
1403
1404       udp0 = ip4_next_header (ip0);
1405       tcp0 = (tcp_header_t *) udp0;
1406       icmp0 = (icmp46_header_t *) udp0;
1407
1408       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1409       rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1410                                sw_if_index0);
1411
1412       if (PREDICT_FALSE (ip0->ttl == 1))
1413         {
1414           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1415           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1416                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1417                                        0);
1418           next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1419           goto trace0;
1420         }
1421
1422       proto0 = ip_proto_to_nat_proto (ip0->protocol);
1423
1424       /* Next configured feature, probably ip4-lookup */
1425       if (is_slow_path)
1426         {
1427           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1428             {
1429               if (nat_in2out_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
1430                 {
1431                   next0 = SNAT_IN2OUT_NEXT_DROP;
1432                   b0->error =
1433                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1434                 }
1435               vlib_increment_simple_counter (is_slow_path ? &sm->
1436                                              counters.slowpath.in2out.
1437                                              other : &sm->counters.fastpath.
1438                                              in2out.other, thread_index,
1439                                              sw_if_index0, 1);
1440               goto trace0;
1441             }
1442
1443           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1444             {
1445               next0 = icmp_in2out_slow_path
1446                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1447                  next0, now, thread_index, &s0);
1448               vlib_increment_simple_counter (is_slow_path ? &sm->
1449                                              counters.slowpath.in2out.
1450                                              icmp : &sm->counters.fastpath.
1451                                              in2out.icmp, thread_index,
1452                                              sw_if_index0, 1);
1453               goto trace0;
1454             }
1455         }
1456       else
1457         {
1458           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1459             {
1460               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1461               goto trace0;
1462             }
1463
1464           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1465             {
1466               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1467               goto trace0;
1468             }
1469         }
1470
1471       init_nat_k (&kv0, ip0->src_address,
1472                   vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
1473                   proto0);
1474
1475       if (clib_bihash_search_8_8
1476           (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1477         {
1478           if (is_slow_path)
1479             {
1480               if (is_output_feature)
1481                 {
1482                   if (PREDICT_FALSE
1483                       (nat_not_translate_output_feature
1484                        (sm, ip0, proto0,
1485                         vnet_buffer (b0)->ip.reass.l4_src_port,
1486                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1487                         thread_index, sw_if_index0)))
1488                     goto trace0;
1489
1490                   /*
1491                    * Send DHCP packets to the ipv4 stack, or we won't
1492                    * be able to use dhcp client on the outside interface
1493                    */
1494                   if (PREDICT_FALSE
1495                       (proto0 == NAT_PROTOCOL_UDP
1496                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1497                            clib_host_to_net_u16
1498                            (UDP_DST_PORT_dhcp_to_server))
1499                        && ip0->dst_address.as_u32 == 0xffffffff))
1500                     goto trace0;
1501                 }
1502               else
1503                 {
1504                   if (PREDICT_FALSE
1505                       (snat_not_translate
1506                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1507                         thread_index)))
1508                     goto trace0;
1509                 }
1510
1511               next0 =
1512                 slow_path (sm, b0, ip0, ip0->src_address,
1513                            vnet_buffer (b0)->ip.reass.l4_src_port,
1514                            rx_fib_index0, proto0, &s0, node, next0,
1515                            thread_index, now);
1516
1517               if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1518                 goto trace0;
1519
1520               if (PREDICT_FALSE (!s0))
1521                 goto trace0;
1522             }
1523           else
1524             {
1525               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1526               goto trace0;
1527             }
1528         }
1529       else
1530         s0 =
1531           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1532                              value0.value);
1533
1534       b0->flags |= VNET_BUFFER_F_IS_NATED;
1535
1536       old_addr0 = ip0->src_address.as_u32;
1537       ip0->src_address = s0->out2in.addr;
1538       new_addr0 = ip0->src_address.as_u32;
1539       if (!is_output_feature)
1540         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1541
1542       sum0 = ip0->checksum;
1543       sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1544                              ip4_header_t, src_address /* changed member */ );
1545       ip0->checksum = ip_csum_fold (sum0);
1546
1547       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1548         {
1549           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1550             {
1551               old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1552               new_port0 = udp0->src_port = s0->out2in.port;
1553               sum0 = tcp0->checksum;
1554               sum0 =
1555                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1556                                 dst_address /* changed member */ );
1557               sum0 =
1558                 ip_csum_update (sum0, old_port0, new_port0,
1559                                 ip4_header_t /* cheat */ ,
1560                                 length /* changed member */ );
1561               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1562               tcp0->checksum = ip_csum_fold (sum0);
1563             }
1564           vlib_increment_simple_counter (is_slow_path ? &sm->
1565                                          counters.slowpath.in2out.tcp : &sm->
1566                                          counters.fastpath.in2out.tcp,
1567                                          thread_index, sw_if_index0, 1);
1568         }
1569       else
1570         {
1571           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1572             {
1573               udp0->src_port = s0->out2in.port;
1574               if (PREDICT_FALSE (udp0->checksum))
1575                 {
1576                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1577                   new_port0 = udp0->src_port;
1578                   sum0 = udp0->checksum;
1579                   sum0 =
1580                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1581                                     dst_address /* changed member */ );
1582                   sum0 =
1583                     ip_csum_update (sum0, old_port0, new_port0,
1584                                     ip4_header_t /* cheat */ ,
1585                                     length /* changed member */ );
1586                   udp0->checksum = ip_csum_fold (sum0);
1587                 }
1588             }
1589           vlib_increment_simple_counter (is_slow_path ? &sm->
1590                                          counters.slowpath.in2out.udp : &sm->
1591                                          counters.fastpath.in2out.udp,
1592                                          thread_index, sw_if_index0, 1);
1593         }
1594
1595       /* Accounting */
1596       nat44_session_update_counters (s0, now,
1597                                      vlib_buffer_length_in_chain (vm, b0),
1598                                      thread_index);
1599       /* Per-user LRU list maintenance */
1600       nat44_session_update_lru (sm, s0, thread_index);
1601
1602     trace0:
1603       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1604                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1605         {
1606           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
1607           t->is_slow_path = is_slow_path;
1608           t->sw_if_index = sw_if_index0;
1609           t->next_index = next0;
1610           t->session_index = ~0;
1611           if (s0)
1612             t->session_index =
1613               s0 - sm->per_thread_data[thread_index].sessions;
1614         }
1615
1616       if (next0 == SNAT_IN2OUT_NEXT_DROP)
1617         {
1618           vlib_increment_simple_counter (is_slow_path ? &sm->
1619                                          counters.slowpath.in2out.
1620                                          drops : &sm->counters.fastpath.
1621                                          in2out.drops, thread_index,
1622                                          sw_if_index0, 1);
1623         }
1624
1625       n_left_from--;
1626       next[0] = next0;
1627       next++;
1628     }
1629
1630   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1631                                frame->n_vectors);
1632   return frame->n_vectors;
1633 }
1634
1635 VLIB_NODE_FN (snat_in2out_node) (vlib_main_t * vm,
1636                                  vlib_node_runtime_t * node,
1637                                  vlib_frame_t * frame)
1638 {
1639   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1640                                      0);
1641 }
1642
1643 /* *INDENT-OFF* */
1644 VLIB_REGISTER_NODE (snat_in2out_node) = {
1645   .name = "nat44-in2out",
1646   .vector_size = sizeof (u32),
1647   .format_trace = format_snat_in2out_trace,
1648   .type = VLIB_NODE_TYPE_INTERNAL,
1649
1650   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1651   .error_strings = snat_in2out_error_strings,
1652
1653   .runtime_data_bytes = sizeof (snat_runtime_t),
1654
1655   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1656
1657   /* edit / add dispositions here */
1658   .next_nodes = {
1659     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1660     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1661     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1662     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1663   },
1664 };
1665 /* *INDENT-ON* */
1666
1667 VLIB_NODE_FN (snat_in2out_output_node) (vlib_main_t * vm,
1668                                         vlib_node_runtime_t * node,
1669                                         vlib_frame_t * frame)
1670 {
1671   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1672                                      1);
1673 }
1674
1675 /* *INDENT-OFF* */
1676 VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1677   .name = "nat44-in2out-output",
1678   .vector_size = sizeof (u32),
1679   .format_trace = format_snat_in2out_trace,
1680   .type = VLIB_NODE_TYPE_INTERNAL,
1681
1682   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1683   .error_strings = snat_in2out_error_strings,
1684
1685   .runtime_data_bytes = sizeof (snat_runtime_t),
1686
1687   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1688
1689   /* edit / add dispositions here */
1690   .next_nodes = {
1691     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1692     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1693     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1694     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1695   },
1696 };
1697 /* *INDENT-ON* */
1698
1699 VLIB_NODE_FN (snat_in2out_slowpath_node) (vlib_main_t * vm,
1700                                           vlib_node_runtime_t * node,
1701                                           vlib_frame_t * frame)
1702 {
1703   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1704                                      0);
1705 }
1706
1707 /* *INDENT-OFF* */
1708 VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1709   .name = "nat44-in2out-slowpath",
1710   .vector_size = sizeof (u32),
1711   .format_trace = format_snat_in2out_trace,
1712   .type = VLIB_NODE_TYPE_INTERNAL,
1713
1714   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1715   .error_strings = snat_in2out_error_strings,
1716
1717   .runtime_data_bytes = sizeof (snat_runtime_t),
1718
1719   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1720
1721   /* edit / add dispositions here */
1722   .next_nodes = {
1723     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1724     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1725     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1726     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1727   },
1728 };
1729 /* *INDENT-ON* */
1730
1731 VLIB_NODE_FN (snat_in2out_output_slowpath_node) (vlib_main_t * vm,
1732                                                  vlib_node_runtime_t * node,
1733                                                  vlib_frame_t * frame)
1734 {
1735   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1736                                      1);
1737 }
1738
1739 /* *INDENT-OFF* */
1740 VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1741   .name = "nat44-in2out-output-slowpath",
1742   .vector_size = sizeof (u32),
1743   .format_trace = format_snat_in2out_trace,
1744   .type = VLIB_NODE_TYPE_INTERNAL,
1745
1746   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1747   .error_strings = snat_in2out_error_strings,
1748
1749   .runtime_data_bytes = sizeof (snat_runtime_t),
1750
1751   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1752
1753   /* edit / add dispositions here */
1754   .next_nodes = {
1755     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1756     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1757     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1758     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1759   },
1760 };
1761 /* *INDENT-ON* */
1762
1763 VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
1764                                       vlib_node_runtime_t * node,
1765                                       vlib_frame_t * frame)
1766 {
1767   u32 n_left_from, *from, *to_next;
1768   snat_in2out_next_t next_index;
1769   snat_main_t *sm = &snat_main;
1770   int is_hairpinning = 0;
1771
1772   from = vlib_frame_vector_args (frame);
1773   n_left_from = frame->n_vectors;
1774   next_index = node->cached_next_index;
1775
1776   while (n_left_from > 0)
1777     {
1778       u32 n_left_to_next;
1779
1780       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1781
1782       while (n_left_from > 0 && n_left_to_next > 0)
1783         {
1784           u32 bi0;
1785           vlib_buffer_t *b0;
1786           u32 next0;
1787           u32 sw_if_index0;
1788           ip4_header_t *ip0;
1789           ip_csum_t sum0;
1790           u32 new_addr0, old_addr0;
1791           u16 old_port0, new_port0;
1792           udp_header_t *udp0;
1793           tcp_header_t *tcp0;
1794           icmp46_header_t *icmp0;
1795           u32 proto0;
1796           u32 rx_fib_index0;
1797           ip4_address_t sm0_addr;
1798           u16 sm0_port;
1799           u32 sm0_fib_index;
1800
1801
1802           /* speculatively enqueue b0 to the current next frame */
1803           bi0 = from[0];
1804           to_next[0] = bi0;
1805           from += 1;
1806           to_next += 1;
1807           n_left_from -= 1;
1808           n_left_to_next -= 1;
1809
1810           b0 = vlib_get_buffer (vm, bi0);
1811           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1812
1813           ip0 = vlib_buffer_get_current (b0);
1814           udp0 = ip4_next_header (ip0);
1815           tcp0 = (tcp_header_t *) udp0;
1816           icmp0 = (icmp46_header_t *) udp0;
1817
1818           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1819           rx_fib_index0 =
1820             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
1821
1822           if (PREDICT_FALSE (ip0->ttl == 1))
1823             {
1824               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1825               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1826                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1827                                            0);
1828               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1829               goto trace0;
1830             }
1831
1832           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1833
1834           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1835             goto trace0;
1836
1837           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1838             {
1839               next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
1840                                    rx_fib_index0, node, next0, ~0, 0, 0);
1841               goto trace0;
1842             }
1843
1844           if (snat_static_mapping_match
1845               (sm, ip0->src_address, udp0->src_port, rx_fib_index0, proto0,
1846                &sm0_addr, &sm0_port, &sm0_fib_index, 0, 0, 0, 0, 0, 0))
1847             {
1848               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
1849               next0 = SNAT_IN2OUT_NEXT_DROP;
1850               goto trace0;
1851             }
1852
1853           new_addr0 = sm0_addr.as_u32;
1854           new_port0 = sm0_port;
1855           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0_fib_index;
1856           old_addr0 = ip0->src_address.as_u32;
1857           ip0->src_address.as_u32 = new_addr0;
1858
1859           sum0 = ip0->checksum;
1860           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1861                                  ip4_header_t,
1862                                  src_address /* changed member */ );
1863           ip0->checksum = ip_csum_fold (sum0);
1864
1865           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
1866             {
1867               old_port0 = udp0->src_port;
1868               udp0->src_port = new_port0;
1869
1870               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1871                 {
1872                   sum0 = tcp0->checksum;
1873                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1874                                          ip4_header_t,
1875                                          dst_address /* changed member */ );
1876                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1877                                          ip4_header_t /* cheat */ ,
1878                                          length /* changed member */ );
1879                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1880                   tcp0->checksum = ip_csum_fold (sum0);
1881                 }
1882               else if (udp0->checksum)
1883                 {
1884                   sum0 = udp0->checksum;
1885                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1886                                          ip4_header_t,
1887                                          dst_address /* changed member */ );
1888                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1889                                          ip4_header_t /* cheat */ ,
1890                                          length /* changed member */ );
1891                   udp0->checksum = ip_csum_fold (sum0);
1892                 }
1893             }
1894           else
1895             {
1896               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1897                 {
1898                   sum0 = tcp0->checksum;
1899                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1900                                          ip4_header_t,
1901                                          dst_address /* changed member */ );
1902                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1903                   tcp0->checksum = ip_csum_fold (sum0);
1904                 }
1905               else if (udp0->checksum)
1906                 {
1907                   sum0 = udp0->checksum;
1908                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1909                                          ip4_header_t,
1910                                          dst_address /* changed member */ );
1911                   udp0->checksum = ip_csum_fold (sum0);
1912                 }
1913             }
1914
1915           /* Hairpinning */
1916           snat_hairpinning (vm, node, sm, b0, ip0, udp0, tcp0, proto0, 0,
1917                             0 /* do_trace */ );
1918           is_hairpinning = 1;
1919
1920         trace0:
1921           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1922                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1923             {
1924               snat_in2out_trace_t *t =
1925                 vlib_add_trace (vm, node, b0, sizeof (*t));
1926               t->sw_if_index = sw_if_index0;
1927               t->next_index = next0;
1928               t->is_hairpinning = is_hairpinning;
1929             }
1930
1931           if (next0 != SNAT_IN2OUT_NEXT_DROP)
1932             {
1933
1934               vlib_increment_simple_counter (&sm->counters.fastpath.
1935                                              in2out.other, sw_if_index0,
1936                                              vm->thread_index, 1);
1937             }
1938
1939           /* verify speculative enqueue, maybe switch current next frame */
1940           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1941                                            to_next, n_left_to_next,
1942                                            bi0, next0);
1943         }
1944
1945       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1946     }
1947
1948   return frame->n_vectors;
1949 }
1950
1951
1952 /* *INDENT-OFF* */
1953 VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
1954   .name = "nat44-in2out-fast",
1955   .vector_size = sizeof (u32),
1956   .format_trace = format_snat_in2out_fast_trace,
1957   .type = VLIB_NODE_TYPE_INTERNAL,
1958
1959   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1960   .error_strings = snat_in2out_error_strings,
1961
1962   .runtime_data_bytes = sizeof (snat_runtime_t),
1963
1964   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1965
1966   /* edit / add dispositions here */
1967   .next_nodes = {
1968     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1969     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1970     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1971     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1972   },
1973 };
1974 /* *INDENT-ON* */
1975
1976 /*
1977  * fd.io coding-style-patch-verification: ON
1978  *
1979  * Local Variables:
1980  * eval: (c-set-style "gnu")
1981  * End:
1982  */