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
  23 #include <vnet/ip/ip.h>
  24 #include <vnet/ethernet/ethernet.h>
  25 #include <vnet/fib/ip4_fib.h>
  26 #include <vnet/udp/udp_local.h>
  27 #include <nat/nat.h>
  28 #include <nat/lib/ipfix_logging.h>
  29 #include <nat/nat_inlines.h>
  30 #include <nat/nat44/inlines.h>
  31 #include <nat/lib/nat_syslog.h>
  32 #include <nat/nat_ha.h>
  33
  34 #include <vppinfra/hash.h>
  35 #include <vppinfra/error.h>
  36 #include <vppinfra/elog.h>
  37 #include <nat/lib/nat_inlines.h>
  38
  39 typedef struct
  40 {
  41   u32 sw_if_index;
  42   u32 next_index;
  43   u32 session_index;
  44   u32 is_slow_path;
  45   u32 is_hairpinning;
  46 } snat_in2out_trace_t;
  47
  48 /* packet trace format function */
  49 static u8 *
  50 format_snat_in2out_trace (u8 * s, va_list * args)
  51 {
  52   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  53   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  54   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  55   char *tag;
  56
  57   tag = t->is_slow_path ? "NAT44_IN2OUT_SLOW_PATH" : "NAT44_IN2OUT_FAST_PATH";
  58
  59   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  60               t->sw_if_index, t->next_index, t->session_index);
  61   if (t->is_hairpinning)
  62     {
  63       s = format (s, ", with-hairpinning");
  64     }
  65
  66   return s;
  67 }
  68
  69 static u8 *
  70 format_snat_in2out_fast_trace (u8 * s, va_list * args)
  71 {
  72   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  73   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  74   snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
  75
  76   s = format (s, "NAT44_IN2OUT_FAST: sw_if_index %d, next index %d",
  77               t->sw_if_index, t->next_index);
  78
  79   return s;
  80 }
  81
  82 #define foreach_snat_in2out_error                       \
  83 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
  84 _(OUT_OF_PORTS, "out of ports")                         \
  85 _(BAD_OUTSIDE_FIB, "outside VRF ID not found")          \
  86 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
  87 _(NO_TRANSLATION, "no translation")                     \
  88 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
  89 _(CANNOT_CREATE_USER, "cannot create NAT user")
  90
  91 typedef enum
  92 {
  93 #define _(sym,str) SNAT_IN2OUT_ERROR_##sym,
  94   foreach_snat_in2out_error
  95 #undef _
  96     SNAT_IN2OUT_N_ERROR,
  97 } snat_in2out_error_t;
  98
  99 static char *snat_in2out_error_strings[] = {
 100 #define _(sym,string) string,
 101   foreach_snat_in2out_error
 102 #undef _
 103 };
 104
 105 typedef enum
 106 {
 107   SNAT_IN2OUT_NEXT_LOOKUP,
 108   SNAT_IN2OUT_NEXT_DROP,
 109   SNAT_IN2OUT_NEXT_ICMP_ERROR,
 110   SNAT_IN2OUT_NEXT_SLOW_PATH,
 111   SNAT_IN2OUT_N_NEXT,
 112 } snat_in2out_next_t;
 113
 114 static inline int
 115 snat_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
 116                     u32 sw_if_index0, ip4_header_t * ip0, u32 proto0,
 117                     u32 rx_fib_index0, u32 thread_index)
 118 {
 119   udp_header_t *udp0 = ip4_next_header (ip0);
 120   clib_bihash_kv_8_8_t kv0, value0;
 121
 122   init_nat_k (&kv0, ip0->dst_address, udp0->dst_port, sm->outside_fib_index,
 123               proto0);
 124
 125   /* NAT packet aimed at external address if */
 126   /* has active sessions */
 127   if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
 128                               &value0))
 129     {
 130       /* or is static mappings */
 131       ip4_address_t placeholder_addr;
 132       u16 placeholder_port;
 133       u32 placeholder_fib_index;
 134       if (!snat_static_mapping_match
 135           (sm, ip0->dst_address, udp0->dst_port, sm->outside_fib_index,
 136            proto0, &placeholder_addr, &placeholder_port,
 137            &placeholder_fib_index, 1, 0, 0, 0, 0, 0, 0))
 138         return 0;
 139     }
 140   else
 141     return 0;
 142
 143   if (sm->forwarding_enabled)
 144     return 1;
 145
 146   return snat_not_translate_fast (sm, node, sw_if_index0, ip0, proto0,
 147                                   rx_fib_index0);
 148 }
 149
 150 static inline int
 151 nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
 152                                   u32 proto0, u16 src_port, u16 dst_port,
 153                                   u32 thread_index, u32 sw_if_index)
 154 {
 155   clib_bihash_kv_8_8_t kv0, value0;
 156   snat_interface_t *i;
 157
 158   /* src NAT check */
 159   init_nat_k (&kv0, ip0->src_address, src_port,
 160               ip4_fib_table_get_index_for_sw_if_index (sw_if_index), proto0);
 161
 162   if (!clib_bihash_search_8_8
 163       (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
 164     return 1;
 165
 166   /* dst NAT check */
 167   init_nat_k (&kv0, ip0->dst_address, dst_port,
 168               ip4_fib_table_get_index_for_sw_if_index (sw_if_index), proto0);
 169   if (!clib_bihash_search_8_8
 170       (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
 171     {
 172       /* hairpinning */
 173     /* *INDENT-OFF* */
 174     pool_foreach (i, sm->output_feature_interfaces,
 175     ({
 176       if ((nat_interface_is_inside(i)) && (sw_if_index == i->sw_if_index))
 177         return 0;
 178     }));
 179     /* *INDENT-ON* */
 180       return 1;
 181     }
 182
 183   return 0;
 184 }
 185
 186 #ifndef CLIB_MARCH_VARIANT
 187 int
 188 nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
 189 {
 190   snat_main_t *sm = &snat_main;
 191   nat44_is_idle_session_ctx_t *ctx = arg;
 192   snat_session_t *s;
 193   u64 sess_timeout_time;
 194   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 195                                                        ctx->thread_index);
 196   clib_bihash_kv_8_8_t s_kv;
 197
 198   s = pool_elt_at_index (tsm->sessions, kv->value);
 199   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 200   if (ctx->now >= sess_timeout_time)
 201     {
 202       init_nat_o2i_k (&s_kv, s);
 203       if (clib_bihash_add_del_8_8 (&tsm->out2in, &s_kv, 0))
 204         nat_elog_warn ("out2in key del failed");
 205
 206       nat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 207                                           s->in2out.addr.as_u32,
 208                                           s->out2in.addr.as_u32,
 209                                           s->nat_proto,
 210                                           s->in2out.port,
 211                                           s->out2in.port,
 212                                           s->in2out.fib_index);
 213
 214       nat_syslog_nat44_apmdel (s->user_index, s->in2out.fib_index,
 215                                &s->in2out.addr, s->in2out.port,
 216                                &s->out2in.addr, s->out2in.port, s->nat_proto);
 217
 218       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 219                    s->ext_host_port, s->nat_proto, s->out2in.fib_index,
 220                    ctx->thread_index);
 221
 222       if (!snat_is_session_static (s))
 223         snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 224                                             &s->out2in.addr,
 225                                             s->out2in.port, s->nat_proto);
 226
 227       nat44_delete_session (sm, s, ctx->thread_index);
 228       return 1;
 229     }
 230
 231   return 0;
 232 }
 233 #endif
 234
 235 static u32
 236 slow_path (snat_main_t * sm, vlib_buffer_t * b0,
 237            ip4_header_t * ip0,
 238            ip4_address_t i2o_addr,
 239            u16 i2o_port,
 240            u32 rx_fib_index0,
 241            nat_protocol_t nat_proto,
 242            snat_session_t ** sessionp,
 243            vlib_node_runtime_t * node, u32 next0, u32 thread_index, f64 now)
 244 {
 245   snat_user_t *u;
 246   snat_session_t *s = 0;
 247   clib_bihash_kv_8_8_t kv0;
 248   u8 is_sm = 0;
 249   nat_outside_fib_t *outside_fib;
 250   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
 251   u8 identity_nat;
 252   fib_prefix_t pfx = {
 253     .fp_proto = FIB_PROTOCOL_IP4,
 254     .fp_len = 32,
 255     .fp_addr = {
 256                 .ip4.as_u32 = ip0->dst_address.as_u32,
 257                 },
 258   };
 259   nat44_is_idle_session_ctx_t ctx0;
 260   ip4_address_t sm_addr;
 261   u16 sm_port;
 262   u32 sm_fib_index;
 263
 264   if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
 265     {
 266       b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_SESSIONS_EXCEEDED];
 267       nat_ipfix_logging_max_sessions (thread_index,
 268                                       sm->max_translations_per_thread);
 269       nat_elog_notice ("maximum sessions exceeded");
 270       return SNAT_IN2OUT_NEXT_DROP;
 271     }
 272
 273   /* First try to match static mapping by local address and port */
 274   if (snat_static_mapping_match
 275       (sm, i2o_addr, i2o_port, rx_fib_index0, nat_proto, &sm_addr,
 276        &sm_port, &sm_fib_index, 0, 0, 0, 0, 0, &identity_nat, 0))
 277     {
 278       /* Try to create dynamic translation */
 279       if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index0,
 280                                                thread_index,
 281                                                nat_proto,
 282                                                &sm_addr, &sm_port,
 283                                                sm->port_per_thread,
 284                                                sm->per_thread_data
 285                                                [thread_index].snat_thread_index))
 286         {
 287           b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
 288           return SNAT_IN2OUT_NEXT_DROP;
 289         }
 290     }
 291   else
 292     {
 293       if (PREDICT_FALSE (identity_nat))
 294         {
 295           *sessionp = s;
 296           return next0;
 297         }
 298
 299       is_sm = 1;
 300     }
 301
 302   u = nat_user_get_or_create (sm, &ip0->src_address, rx_fib_index0,
 303                               thread_index);
 304   if (!u)
 305     {
 306       b0->error = node->errors[SNAT_IN2OUT_ERROR_CANNOT_CREATE_USER];
 307       return SNAT_IN2OUT_NEXT_DROP;
 308     }
 309
 310   s = nat_session_alloc_or_recycle (sm, u, thread_index, now);
 311   if (!s)
 312     {
 313       nat44_delete_user_with_no_session (sm, u, thread_index);
 314       nat_elog_warn ("create NAT session failed");
 315       return SNAT_IN2OUT_NEXT_DROP;
 316     }
 317
 318   if (is_sm)
 319     s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 320   user_session_increment (sm, u, is_sm);
 321   s->in2out.addr = i2o_addr;
 322   s->in2out.port = i2o_port;
 323   s->in2out.fib_index = rx_fib_index0;
 324   s->nat_proto = nat_proto;
 325   s->out2in.addr = sm_addr;
 326   s->out2in.port = sm_port;
 327   s->out2in.fib_index = sm->outside_fib_index;
 328   switch (vec_len (sm->outside_fibs))
 329     {
 330     case 0:
 331       s->out2in.fib_index = sm->outside_fib_index;
 332       break;
 333     case 1:
 334       s->out2in.fib_index = sm->outside_fibs[0].fib_index;
 335       break;
 336     default:
 337       /* *INDENT-OFF* */
 338       vec_foreach (outside_fib, sm->outside_fibs)
 339         {
 340           fei = fib_table_lookup (outside_fib->fib_index, &pfx);
 341           if (FIB_NODE_INDEX_INVALID != fei)
 342             {
 343               if (fib_entry_get_resolving_interface (fei) != ~0)
 344                 {
 345                   s->out2in.fib_index = outside_fib->fib_index;
 346                   break;
 347                 }
 348             }
 349         }
 350       /* *INDENT-ON* */
 351       break;
 352     }
 353   s->ext_host_addr.as_u32 = ip0->dst_address.as_u32;
 354   s->ext_host_port = vnet_buffer (b0)->ip.reass.l4_dst_port;
 355   *sessionp = s;
 356
 357   /* Add to translation hashes */
 358   ctx0.now = now;
 359   ctx0.thread_index = thread_index;
 360   init_nat_i2o_kv (&kv0, s, s - sm->per_thread_data[thread_index].sessions);
 361   if (clib_bihash_add_or_overwrite_stale_8_8
 362       (&sm->per_thread_data[thread_index].in2out, &kv0,
 363        nat44_i2o_is_idle_session_cb, &ctx0))
 364     nat_elog_notice ("in2out key add failed");
 365
 366   init_nat_o2i_kv (&kv0, s, s - sm->per_thread_data[thread_index].sessions);
 367   if (clib_bihash_add_or_overwrite_stale_8_8
 368       (&sm->per_thread_data[thread_index].out2in, &kv0,
 369        nat44_o2i_is_idle_session_cb, &ctx0))
 370     nat_elog_notice ("out2in key add failed");
 371
 372   /* log NAT event */
 373   nat_ipfix_logging_nat44_ses_create (thread_index,
 374                                       s->in2out.addr.as_u32,
 375                                       s->out2in.addr.as_u32,
 376                                       s->nat_proto,
 377                                       s->in2out.port,
 378                                       s->out2in.port, s->in2out.fib_index);
 379
 380   nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
 381                            &s->in2out.addr, s->in2out.port, &s->out2in.addr,
 382                            s->out2in.port, s->nat_proto);
 383
 384   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 385                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 386                &s->ext_host_nat_addr, s->ext_host_nat_port,
 387                s->nat_proto, s->in2out.fib_index, s->flags, thread_index, 0);
 388
 389   return next0;
 390 }
 391
 392 #ifndef CLIB_MARCH_VARIANT
 393 static_always_inline snat_in2out_error_t
 394 icmp_get_key (vlib_buffer_t * b, ip4_header_t * ip0,
 395               ip4_address_t * addr, u16 * port, nat_protocol_t * nat_proto)
 396 {
 397   icmp46_header_t *icmp0;
 398   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 399   ip4_header_t *inner_ip0 = 0;
 400   void *l4_header = 0;
 401   icmp46_header_t *inner_icmp0;
 402
 403   icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
 404   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 405
 406   if (!icmp_type_is_error_message
 407       (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
 408     {
 409       *nat_proto = NAT_PROTOCOL_ICMP;
 410       *addr = ip0->src_address;
 411       *port = vnet_buffer (b)->ip.reass.l4_src_port;
 412     }
 413   else
 414     {
 415       inner_ip0 = (ip4_header_t *) (echo0 + 1);
 416       l4_header = ip4_next_header (inner_ip0);
 417       *nat_proto = ip_proto_to_nat_proto (inner_ip0->protocol);
 418       *addr = inner_ip0->dst_address;
 419       switch (*nat_proto)
 420         {
 421         case NAT_PROTOCOL_ICMP:
 422           inner_icmp0 = (icmp46_header_t *) l4_header;
 423           inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 424           *port = inner_echo0->identifier;
 425           break;
 426         case NAT_PROTOCOL_UDP:
 427         case NAT_PROTOCOL_TCP:
 428           *port = ((tcp_udp_header_t *) l4_header)->dst_port;
 429           break;
 430         default:
 431           return SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL;
 432         }
 433     }
 434   return -1;                    /* success */
 435 }
 436
 437 /**
 438  * Get address and port values to be used for ICMP packet translation
 439  * and create session if needed
 440  *
 441  * @param[in,out] sm             NAT main
 442  * @param[in,out] node           NAT node runtime
 443  * @param[in] thread_index       thread index
 444  * @param[in,out] b0             buffer containing packet to be translated
 445  * @param[in,out] ip0            ip header
 446  * @param[out] p_proto           protocol used for matching
 447  * @param[out] p_value           address and port after NAT translation
 448  * @param[out] p_dont_translate  if packet should not be translated
 449  * @param d                      optional parameter
 450  * @param e                      optional parameter
 451  */
 452 u32
 453 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
 454                         u32 thread_index, vlib_buffer_t * b0,
 455                         ip4_header_t * ip0, ip4_address_t * addr, u16 * port,
 456                         u32 * fib_index, nat_protocol_t * proto, void *d,
 457                         void *e, u8 * dont_translate)
 458 {
 459   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 460   u32 sw_if_index0;
 461   snat_session_t *s0 = 0;
 462   clib_bihash_kv_8_8_t kv0, value0;
 463   u32 next0 = ~0;
 464   int err;
 465   vlib_main_t *vm = vlib_get_main ();
 466   *dont_translate = 0;
 467
 468   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 469   *fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 470
 471   err = icmp_get_key (b0, ip0, addr, port, proto);
 472   if (err != -1)
 473     {
 474       b0->error = node->errors[err];
 475       next0 = SNAT_IN2OUT_NEXT_DROP;
 476       goto out;
 477     }
 478
 479   init_nat_k (&kv0, *addr, *port, *fib_index, *proto);
 480   if (clib_bihash_search_8_8 (&tsm->in2out, &kv0, &value0))
 481     {
 482       if (vnet_buffer (b0)->sw_if_index[VLIB_TX] != ~0)
 483         {
 484           if (PREDICT_FALSE
 485               (nat_not_translate_output_feature
 486                (sm, ip0, *proto, *port, *port, thread_index, sw_if_index0)))
 487             {
 488               *dont_translate = 1;
 489               goto out;
 490             }
 491         }
 492       else
 493         {
 494           if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
 495                                                  ip0, NAT_PROTOCOL_ICMP,
 496                                                  *fib_index, thread_index)))
 497             {
 498               *dont_translate = 1;
 499               goto out;
 500             }
 501         }
 502
 503       if (PREDICT_FALSE
 504           (icmp_type_is_error_message
 505            (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags)))
 506         {
 507           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 508           next0 = SNAT_IN2OUT_NEXT_DROP;
 509           goto out;
 510         }
 511
 512       next0 =
 513         slow_path (sm, b0, ip0, *addr, *port, *fib_index, *proto, &s0, node,
 514                    next0, thread_index, vlib_time_now (vm));
 515
 516       if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
 517         goto out;
 518
 519       if (!s0)
 520         {
 521           *dont_translate = 1;
 522           goto out;
 523         }
 524     }
 525   else
 526     {
 527       if (PREDICT_FALSE
 528           (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 529            ICMP4_echo_request
 530            && vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 531            ICMP4_echo_reply
 532            && !icmp_type_is_error_message (vnet_buffer (b0)->ip.
 533                                            reass.icmp_type_or_tcp_flags)))
 534         {
 535           b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 536           next0 = SNAT_IN2OUT_NEXT_DROP;
 537           goto out;
 538         }
 539
 540       s0 = pool_elt_at_index (tsm->sessions, value0.value);
 541     }
 542
 543 out:
 544   if (s0)
 545     {
 546       *addr = s0->out2in.addr;
 547       *port = s0->out2in.port;
 548       *fib_index = s0->out2in.fib_index;
 549     }
 550   if (d)
 551     *(snat_session_t **) (d) = s0;
 552   return next0;
 553 }
 554 #endif
 555
 556 #ifndef CLIB_MARCH_VARIANT
 557 /**
 558  * Get address and port values to be used for ICMP packet translation
 559  *
 560  * @param[in] sm                 NAT main
 561  * @param[in,out] node           NAT node runtime
 562  * @param[in] thread_index       thread index
 563  * @param[in,out] b0             buffer containing packet to be translated
 564  * @param[in,out] ip0            ip header
 565  * @param[out] p_proto           protocol used for matching
 566  * @param[out] p_value           address and port after NAT translation
 567  * @param[out] p_dont_translate  if packet should not be translated
 568  * @param d                      optional parameter
 569  * @param e                      optional parameter
 570  */
 571 u32
 572 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
 573                         u32 thread_index, vlib_buffer_t * b0,
 574                         ip4_header_t * ip0, ip4_address_t * addr, u16 * port,
 575                         u32 * fib_index, nat_protocol_t * proto, void *d,
 576                         void *e, u8 * dont_translate)
 577 {
 578   u32 sw_if_index0;
 579   u8 is_addr_only;
 580   u32 next0 = ~0;
 581   int err;
 582   *dont_translate = 0;
 583
 584   sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 585   *fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
 586
 587   err = icmp_get_key (b0, ip0, addr, port, proto);
 588   if (err != -1)
 589     {
 590       b0->error = node->errors[err];
 591       next0 = SNAT_IN2OUT_NEXT_DROP;
 592       goto out;
 593     }
 594
 595   ip4_address_t sm_addr;
 596   u16 sm_port;
 597   u32 sm_fib_index;
 598
 599   if (snat_static_mapping_match
 600       (sm, *addr, *port, *fib_index, *proto, &sm_addr, &sm_port,
 601        &sm_fib_index, 0, &is_addr_only, 0, 0, 0, 0, 0))
 602     {
 603       if (PREDICT_FALSE (snat_not_translate_fast (sm, node, sw_if_index0, ip0,
 604                                                   IP_PROTOCOL_ICMP,
 605                                                   *fib_index)))
 606         {
 607           *dont_translate = 1;
 608           goto out;
 609         }
 610
 611       if (icmp_type_is_error_message
 612           (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags))
 613         {
 614           next0 = SNAT_IN2OUT_NEXT_DROP;
 615           goto out;
 616         }
 617
 618       b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
 619       next0 = SNAT_IN2OUT_NEXT_DROP;
 620       goto out;
 621     }
 622
 623   if (PREDICT_FALSE
 624       (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_request
 625        && (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags !=
 626            ICMP4_echo_reply || !is_addr_only)
 627        && !icmp_type_is_error_message (vnet_buffer (b0)->ip.
 628                                        reass.icmp_type_or_tcp_flags)))
 629     {
 630       b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
 631       next0 = SNAT_IN2OUT_NEXT_DROP;
 632       goto out;
 633     }
 634
 635 out:
 636   return next0;
 637 }
 638 #endif
 639
 640 #ifndef CLIB_MARCH_VARIANT
 641 u32
 642 icmp_in2out (snat_main_t * sm,
 643              vlib_buffer_t * b0,
 644              ip4_header_t * ip0,
 645              icmp46_header_t * icmp0,
 646              u32 sw_if_index0,
 647              u32 rx_fib_index0,
 648              vlib_node_runtime_t * node,
 649              u32 next0, u32 thread_index, void *d, void *e)
 650 {
 651   vlib_main_t *vm = vlib_get_main ();
 652   ip4_address_t addr;
 653   u16 port;
 654   u32 fib_index;
 655   nat_protocol_t protocol;
 656   icmp_echo_header_t *echo0, *inner_echo0 = 0;
 657   ip4_header_t *inner_ip0;
 658   void *l4_header = 0;
 659   icmp46_header_t *inner_icmp0;
 660   u8 dont_translate;
 661   u32 new_addr0, old_addr0;
 662   u16 old_id0, new_id0;
 663   u16 old_checksum0, new_checksum0;
 664   ip_csum_t sum0;
 665   u16 checksum0;
 666   u32 next0_tmp;
 667
 668   echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 669
 670   next0_tmp =
 671     sm->icmp_match_in2out_cb (sm, node, thread_index, b0, ip0, &addr, &port,
 672                               &fib_index, &protocol, d, e, &dont_translate);
 673   if (next0_tmp != ~0)
 674     next0 = next0_tmp;
 675   if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
 676     goto out;
 677
 678   if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
 679     {
 680       sum0 =
 681         ip_incremental_checksum_buffer (vm, b0,
 682                                         (u8 *) icmp0 -
 683                                         (u8 *) vlib_buffer_get_current (b0),
 684                                         ntohs (ip0->length) -
 685                                         ip4_header_bytes (ip0), 0);
 686       checksum0 = ~ip_csum_fold (sum0);
 687       if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff))
 688         {
 689           next0 = SNAT_IN2OUT_NEXT_DROP;
 690           goto out;
 691         }
 692     }
 693
 694   old_addr0 = ip0->src_address.as_u32;
 695   new_addr0 = ip0->src_address.as_u32 = addr.as_u32;
 696
 697   sum0 = ip0->checksum;
 698   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 699                          src_address /* changed member */ );
 700   ip0->checksum = ip_csum_fold (sum0);
 701
 702   if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 703     {
 704       if (icmp0->checksum == 0)
 705         icmp0->checksum = 0xffff;
 706
 707       if (!icmp_type_is_error_message (icmp0->type))
 708         {
 709           new_id0 = port;
 710           if (PREDICT_FALSE (new_id0 != echo0->identifier))
 711             {
 712               old_id0 = echo0->identifier;
 713               new_id0 = port;
 714               echo0->identifier = new_id0;
 715
 716               sum0 = icmp0->checksum;
 717               sum0 =
 718                 ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 719                                 identifier);
 720               icmp0->checksum = ip_csum_fold (sum0);
 721             }
 722         }
 723       else
 724         {
 725           inner_ip0 = (ip4_header_t *) (echo0 + 1);
 726           l4_header = ip4_next_header (inner_ip0);
 727
 728           if (!ip4_header_checksum_is_valid (inner_ip0))
 729             {
 730               next0 = SNAT_IN2OUT_NEXT_DROP;
 731               goto out;
 732             }
 733
 734           /* update inner destination IP address */
 735           old_addr0 = inner_ip0->dst_address.as_u32;
 736           inner_ip0->dst_address = addr;
 737           new_addr0 = inner_ip0->dst_address.as_u32;
 738           sum0 = icmp0->checksum;
 739           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 740                                  dst_address /* changed member */ );
 741           icmp0->checksum = ip_csum_fold (sum0);
 742
 743           /* update inner IP header checksum */
 744           old_checksum0 = inner_ip0->checksum;
 745           sum0 = inner_ip0->checksum;
 746           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 747                                  dst_address /* changed member */ );
 748           inner_ip0->checksum = ip_csum_fold (sum0);
 749           new_checksum0 = inner_ip0->checksum;
 750           sum0 = icmp0->checksum;
 751           sum0 =
 752             ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
 753                             checksum);
 754           icmp0->checksum = ip_csum_fold (sum0);
 755
 756           switch (protocol)
 757             {
 758             case NAT_PROTOCOL_ICMP:
 759               inner_icmp0 = (icmp46_header_t *) l4_header;
 760               inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 761
 762               old_id0 = inner_echo0->identifier;
 763               new_id0 = port;
 764               inner_echo0->identifier = new_id0;
 765
 766               sum0 = icmp0->checksum;
 767               sum0 =
 768                 ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
 769                                 identifier);
 770               icmp0->checksum = ip_csum_fold (sum0);
 771               break;
 772             case NAT_PROTOCOL_UDP:
 773             case NAT_PROTOCOL_TCP:
 774               old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
 775               new_id0 = port;
 776               ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
 777
 778               sum0 = icmp0->checksum;
 779               sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
 780                                      dst_port);
 781               icmp0->checksum = ip_csum_fold (sum0);
 782               break;
 783             default:
 784               ASSERT (0);
 785             }
 786         }
 787     }
 788
 789   if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
 790     {
 791       if (0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
 792                                       sm->endpoint_dependent))
 793         vnet_buffer (b0)->sw_if_index[VLIB_TX] = fib_index;
 794     }
 795
 796 out:
 797   return next0;
 798 }
 799 #endif
 800
 801 static inline u32
 802 icmp_in2out_slow_path (snat_main_t * sm,
 803                        vlib_buffer_t * b0,
 804                        ip4_header_t * ip0,
 805                        icmp46_header_t * icmp0,
 806                        u32 sw_if_index0,
 807                        u32 rx_fib_index0,
 808                        vlib_node_runtime_t * node,
 809                        u32 next0,
 810                        f64 now, u32 thread_index, snat_session_t ** p_s0)
 811 {
 812   vlib_main_t *vm = vlib_get_main ();
 813
 814   next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 815                        next0, thread_index, p_s0, 0);
 816   snat_session_t *s0 = *p_s0;
 817   if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
 818     {
 819       /* Accounting */
 820       nat44_session_update_counters (s0, now,
 821                                      vlib_buffer_length_in_chain
 822                                      (vm, b0), thread_index);
 823       /* Per-user LRU list maintenance */
 824       nat44_session_update_lru (sm, s0, thread_index);
 825     }
 826   return next0;
 827 }
 828
 829 static int
 830 nat_in2out_sm_unknown_proto (snat_main_t * sm,
 831                              vlib_buffer_t * b,
 832                              ip4_header_t * ip, u32 rx_fib_index)
 833 {
 834   clib_bihash_kv_8_8_t kv, value;
 835   snat_static_mapping_t *m;
 836   u32 old_addr, new_addr;
 837   ip_csum_t sum;
 838
 839   init_nat_k (&kv, ip->src_address, 0, rx_fib_index, 0);
 840   if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
 841     return 1;
 842
 843   m = pool_elt_at_index (sm->static_mappings, value.value);
 844
 845   old_addr = ip->src_address.as_u32;
 846   new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
 847   sum = ip->checksum;
 848   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
 849   ip->checksum = ip_csum_fold (sum);
 850
 851
 852   /* Hairpinning */
 853   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 854     {
 855       vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 856       nat_hairpinning_sm_unknown_proto (sm, b, ip);
 857     }
 858
 859   return 0;
 860 }
 861
 862 static inline uword
 863 snat_in2out_node_fn_inline (vlib_main_t * vm,
 864                             vlib_node_runtime_t * node,
 865                             vlib_frame_t * frame, int is_slow_path,
 866                             int is_output_feature)
 867 {
 868   u32 n_left_from, *from;
 869   snat_main_t *sm = &snat_main;
 870   f64 now = vlib_time_now (vm);
 871   u32 thread_index = vm->thread_index;
 872
 873   from = vlib_frame_vector_args (frame);
 874   n_left_from = frame->n_vectors;
 875
 876   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 877   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 878   vlib_get_buffers (vm, from, b, n_left_from);
 879
 880   while (n_left_from >= 2)
 881     {
 882       vlib_buffer_t *b0, *b1;
 883       u32 next0, next1;
 884       u32 sw_if_index0, sw_if_index1;
 885       ip4_header_t *ip0, *ip1;
 886       ip_csum_t sum0, sum1;
 887       u32 new_addr0, old_addr0, new_addr1, old_addr1;
 888       u16 old_port0, new_port0, old_port1, new_port1;
 889       udp_header_t *udp0, *udp1;
 890       tcp_header_t *tcp0, *tcp1;
 891       icmp46_header_t *icmp0, *icmp1;
 892       u32 rx_fib_index0, rx_fib_index1;
 893       u32 proto0, proto1;
 894       snat_session_t *s0 = 0, *s1 = 0;
 895       clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
 896       u32 iph_offset0 = 0, iph_offset1 = 0;
 897
 898       b0 = *b;
 899       b++;
 900       b1 = *b;
 901       b++;
 902
 903       /* Prefetch next iteration. */
 904       if (PREDICT_TRUE (n_left_from >= 4))
 905         {
 906           vlib_buffer_t *p2, *p3;
 907
 908           p2 = *b;
 909           p3 = *(b + 1);
 910
 911           vlib_prefetch_buffer_header (p2, LOAD);
 912           vlib_prefetch_buffer_header (p3, LOAD);
 913
 914           CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
 915           CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, LOAD);
 916         }
 917
 918       if (is_output_feature)
 919         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
 920
 921       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
 922                               iph_offset0);
 923
 924       udp0 = ip4_next_header (ip0);
 925       tcp0 = (tcp_header_t *) udp0;
 926       icmp0 = (icmp46_header_t *) udp0;
 927
 928       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 929       rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 930                                sw_if_index0);
 931
 932       next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
 933
 934       if (PREDICT_FALSE (ip0->ttl == 1))
 935         {
 936           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 937           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 938                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
 939                                        0);
 940           next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
 941           goto trace00;
 942         }
 943
 944       proto0 = ip_proto_to_nat_proto (ip0->protocol);
 945
 946       /* Next configured feature, probably ip4-lookup */
 947       if (is_slow_path)
 948         {
 949           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 950             {
 951               if (nat_in2out_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 952                 {
 953                   next0 = SNAT_IN2OUT_NEXT_DROP;
 954                   b0->error =
 955                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
 956                 }
 957               vlib_increment_simple_counter (is_slow_path ? &sm->
 958                                              counters.slowpath.in2out.
 959                                              other : &sm->counters.fastpath.
 960                                              in2out.other, thread_index,
 961                                              sw_if_index0, 1);
 962               goto trace00;
 963             }
 964
 965           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 966             {
 967               next0 = icmp_in2out_slow_path
 968                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
 969                  node, next0, now, thread_index, &s0);
 970               vlib_increment_simple_counter (is_slow_path ? &sm->
 971                                              counters.slowpath.in2out.
 972                                              icmp : &sm->counters.fastpath.
 973                                              in2out.icmp, thread_index,
 974                                              sw_if_index0, 1);
 975               goto trace00;
 976             }
 977         }
 978       else
 979         {
 980           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 981             {
 982               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 983               goto trace00;
 984             }
 985
 986           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 987             {
 988               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 989               goto trace00;
 990             }
 991         }
 992
 993       init_nat_k (&kv0, ip0->src_address,
 994                   vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
 995                   proto0);
 996       if (PREDICT_FALSE
 997           (clib_bihash_search_8_8
 998            (&sm->per_thread_data[thread_index].in2out, &kv0, &value0) != 0))
 999         {
1000           if (is_slow_path)
1001             {
1002               if (is_output_feature)
1003                 {
1004                   if (PREDICT_FALSE
1005                       (nat_not_translate_output_feature
1006                        (sm, ip0, proto0,
1007                         vnet_buffer (b0)->ip.reass.l4_src_port,
1008                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1009                         thread_index, sw_if_index0)))
1010                     goto trace00;
1011
1012                   /*
1013                    * Send DHCP packets to the ipv4 stack, or we won't
1014                    * be able to use dhcp client on the outside interface
1015                    */
1016                   if (PREDICT_FALSE
1017                       (proto0 == NAT_PROTOCOL_UDP
1018                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1019                            clib_host_to_net_u16
1020                            (UDP_DST_PORT_dhcp_to_server))
1021                        && ip0->dst_address.as_u32 == 0xffffffff))
1022                     goto trace00;
1023                 }
1024               else
1025                 {
1026                   if (PREDICT_FALSE
1027                       (snat_not_translate
1028                        (sm, node, sw_if_index0, ip0, proto0,
1029                         rx_fib_index0, thread_index)))
1030                     goto trace00;
1031                 }
1032
1033               next0 = slow_path (sm, b0, ip0,
1034                                  ip0->src_address,
1035                                  vnet_buffer (b0)->ip.reass.l4_src_port,
1036                                  rx_fib_index0,
1037                                  proto0, &s0, node, next0, thread_index, now);
1038               if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1039                 goto trace00;
1040
1041               if (PREDICT_FALSE (!s0))
1042                 goto trace00;
1043             }
1044           else
1045             {
1046               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1047               goto trace00;
1048             }
1049         }
1050       else
1051         s0 =
1052           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1053                              value0.value);
1054
1055       b0->flags |= VNET_BUFFER_F_IS_NATED;
1056
1057       old_addr0 = ip0->src_address.as_u32;
1058       ip0->src_address = s0->out2in.addr;
1059       new_addr0 = ip0->src_address.as_u32;
1060       if (!is_output_feature)
1061         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1062
1063       sum0 = ip0->checksum;
1064       sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1065                              ip4_header_t, src_address /* changed member */ );
1066       ip0->checksum = ip_csum_fold (sum0);
1067
1068
1069       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1070         {
1071           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1072             {
1073               old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1074               new_port0 = udp0->src_port = s0->out2in.port;
1075               sum0 = tcp0->checksum;
1076               sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1077                                      ip4_header_t,
1078                                      dst_address /* changed member */ );
1079               sum0 = ip_csum_update (sum0, old_port0, new_port0,
1080                                      ip4_header_t /* cheat */ ,
1081                                      length /* changed member */ );
1082               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1083               tcp0->checksum = ip_csum_fold (sum0);
1084             }
1085           vlib_increment_simple_counter (is_slow_path ? &sm->
1086                                          counters.slowpath.in2out.tcp : &sm->
1087                                          counters.fastpath.in2out.tcp,
1088                                          thread_index, sw_if_index0, 1);
1089         }
1090       else
1091         {
1092           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1093             {
1094               udp0->src_port = s0->out2in.port;
1095               if (PREDICT_FALSE (udp0->checksum))
1096                 {
1097                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1098                   new_port0 = udp0->src_port;
1099                   sum0 = udp0->checksum;
1100                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address  /* changed member */
1101                     );
1102                   sum0 =
1103                     ip_csum_update (sum0, old_port0, new_port0,
1104                                     ip4_header_t /* cheat */ ,
1105                                     length /* changed member */ );
1106                   udp0->checksum = ip_csum_fold (sum0);
1107                 }
1108             }
1109           vlib_increment_simple_counter (is_slow_path ? &sm->
1110                                          counters.slowpath.in2out.udp : &sm->
1111                                          counters.fastpath.in2out.udp,
1112                                          thread_index, sw_if_index0, 1);
1113         }
1114
1115       /* Accounting */
1116       nat44_session_update_counters (s0, now,
1117                                      vlib_buffer_length_in_chain (vm, b0),
1118                                      thread_index);
1119       /* Per-user LRU list maintenance */
1120       nat44_session_update_lru (sm, s0, thread_index);
1121     trace00:
1122
1123       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1124                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1125         {
1126           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
1127           t->is_slow_path = is_slow_path;
1128           t->sw_if_index = sw_if_index0;
1129           t->next_index = next0;
1130           t->session_index = ~0;
1131           if (s0)
1132             t->session_index =
1133               s0 - sm->per_thread_data[thread_index].sessions;
1134         }
1135
1136       if (next0 == SNAT_IN2OUT_NEXT_DROP)
1137         {
1138           vlib_increment_simple_counter (is_slow_path ? &sm->
1139                                          counters.slowpath.in2out.
1140                                          drops : &sm->counters.fastpath.
1141                                          in2out.drops, thread_index,
1142                                          sw_if_index0, 1);
1143         }
1144
1145       if (is_output_feature)
1146         iph_offset1 = vnet_buffer (b1)->ip.reass.save_rewrite_length;
1147
1148       ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1149                               iph_offset1);
1150
1151       udp1 = ip4_next_header (ip1);
1152       tcp1 = (tcp_header_t *) udp1;
1153       icmp1 = (icmp46_header_t *) udp1;
1154
1155       sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1156       rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1157                                sw_if_index1);
1158
1159       if (PREDICT_FALSE (ip1->ttl == 1))
1160         {
1161           vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1162           icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1163                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1164                                        0);
1165           next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1166           goto trace01;
1167         }
1168
1169       proto1 = ip_proto_to_nat_proto (ip1->protocol);
1170
1171       /* Next configured feature, probably ip4-lookup */
1172       if (is_slow_path)
1173         {
1174           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1175             {
1176               if (nat_in2out_sm_unknown_proto (sm, b1, ip1, rx_fib_index1))
1177                 {
1178                   next1 = SNAT_IN2OUT_NEXT_DROP;
1179                   b1->error =
1180                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1181                 }
1182               vlib_increment_simple_counter (is_slow_path ? &sm->
1183                                              counters.slowpath.in2out.
1184                                              other : &sm->counters.fastpath.
1185                                              in2out.other, thread_index,
1186                                              sw_if_index1, 1);
1187               goto trace01;
1188             }
1189
1190           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1191             {
1192               next1 = icmp_in2out_slow_path
1193                 (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1194                  next1, now, thread_index, &s1);
1195               vlib_increment_simple_counter (is_slow_path ? &sm->
1196                                              counters.slowpath.in2out.
1197                                              icmp : &sm->counters.fastpath.
1198                                              in2out.icmp, thread_index,
1199                                              sw_if_index1, 1);
1200               goto trace01;
1201             }
1202         }
1203       else
1204         {
1205           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
1206             {
1207               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1208               goto trace01;
1209             }
1210
1211           if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
1212             {
1213               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1214               goto trace01;
1215             }
1216         }
1217
1218       init_nat_k (&kv1, ip1->src_address,
1219                   vnet_buffer (b1)->ip.reass.l4_src_port, rx_fib_index1,
1220                   proto1);
1221       if (PREDICT_FALSE
1222           (clib_bihash_search_8_8
1223            (&sm->per_thread_data[thread_index].in2out, &kv1, &value1) != 0))
1224         {
1225           if (is_slow_path)
1226             {
1227               if (is_output_feature)
1228                 {
1229                   if (PREDICT_FALSE
1230                       (nat_not_translate_output_feature
1231                        (sm, ip1, proto1,
1232                         vnet_buffer (b1)->ip.reass.l4_src_port,
1233                         vnet_buffer (b1)->ip.reass.l4_dst_port,
1234                         thread_index, sw_if_index1)))
1235                     goto trace01;
1236
1237                   /*
1238                    * Send DHCP packets to the ipv4 stack, or we won't
1239                    * be able to use dhcp client on the outside interface
1240                    */
1241                   if (PREDICT_FALSE
1242                       (proto1 == NAT_PROTOCOL_UDP
1243                        && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
1244                            clib_host_to_net_u16
1245                            (UDP_DST_PORT_dhcp_to_server))
1246                        && ip1->dst_address.as_u32 == 0xffffffff))
1247                     goto trace01;
1248                 }
1249               else
1250                 {
1251                   if (PREDICT_FALSE
1252                       (snat_not_translate
1253                        (sm, node, sw_if_index1, ip1, proto1,
1254                         rx_fib_index1, thread_index)))
1255                     goto trace01;
1256                 }
1257
1258               next1 =
1259                 slow_path (sm, b1, ip1, ip1->src_address,
1260                            vnet_buffer (b1)->ip.reass.l4_src_port,
1261                            rx_fib_index1, proto1, &s1, node, next1,
1262                            thread_index, now);
1263               if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1264                 goto trace01;
1265
1266               if (PREDICT_FALSE (!s1))
1267                 goto trace01;
1268             }
1269           else
1270             {
1271               next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1272               goto trace01;
1273             }
1274         }
1275       else
1276         s1 =
1277           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1278                              value1.value);
1279
1280       b1->flags |= VNET_BUFFER_F_IS_NATED;
1281
1282       old_addr1 = ip1->src_address.as_u32;
1283       ip1->src_address = s1->out2in.addr;
1284       new_addr1 = ip1->src_address.as_u32;
1285       if (!is_output_feature)
1286         vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1287
1288       sum1 = ip1->checksum;
1289       sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1290                              ip4_header_t, src_address /* changed member */ );
1291       ip1->checksum = ip_csum_fold (sum1);
1292
1293       if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
1294         {
1295           if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
1296             {
1297               old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1298               new_port1 = udp1->src_port = s1->out2in.port;
1299               sum1 = tcp1->checksum;
1300               sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1301                                      ip4_header_t,
1302                                      dst_address /* changed member */ );
1303               sum1 = ip_csum_update (sum1, old_port1, new_port1,
1304                                      ip4_header_t /* cheat */ ,
1305                                      length /* changed member */ );
1306               mss_clamping (sm->mss_clamping, tcp1, &sum1);
1307               tcp1->checksum = ip_csum_fold (sum1);
1308             }
1309           vlib_increment_simple_counter (is_slow_path ? &sm->
1310                                          counters.slowpath.in2out.tcp : &sm->
1311                                          counters.fastpath.in2out.tcp,
1312                                          thread_index, sw_if_index1, 1);
1313         }
1314       else
1315         {
1316           if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
1317             {
1318               udp1->src_port = s1->out2in.port;
1319               if (PREDICT_FALSE (udp1->checksum))
1320                 {
1321                   old_port1 = vnet_buffer (b1)->ip.reass.l4_src_port;
1322                   new_port1 = udp1->src_port;
1323                   sum1 = udp1->checksum;
1324                   sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t, dst_address  /* changed member */
1325                     );
1326                   sum1 =
1327                     ip_csum_update (sum1, old_port1, new_port1,
1328                                     ip4_header_t /* cheat */ ,
1329                                     length /* changed member */ );
1330                   udp1->checksum = ip_csum_fold (sum1);
1331                 }
1332             }
1333           vlib_increment_simple_counter (is_slow_path ? &sm->
1334                                          counters.slowpath.in2out.udp : &sm->
1335                                          counters.fastpath.in2out.udp,
1336                                          thread_index, sw_if_index1, 1);
1337         }
1338
1339       /* Accounting */
1340       nat44_session_update_counters (s1, now,
1341                                      vlib_buffer_length_in_chain (vm, b1),
1342                                      thread_index);
1343       /* Per-user LRU list maintenance */
1344       nat44_session_update_lru (sm, s1, thread_index);
1345     trace01:
1346
1347       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1348                          && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1349         {
1350           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b1, sizeof (*t));
1351           t->sw_if_index = sw_if_index1;
1352           t->next_index = next1;
1353           t->session_index = ~0;
1354           if (s1)
1355             t->session_index =
1356               s1 - sm->per_thread_data[thread_index].sessions;
1357         }
1358
1359       if (next1 == SNAT_IN2OUT_NEXT_DROP)
1360         {
1361           vlib_increment_simple_counter (is_slow_path ? &sm->
1362                                          counters.slowpath.in2out.
1363                                          drops : &sm->counters.fastpath.
1364                                          in2out.drops, thread_index,
1365                                          sw_if_index1, 1);
1366         }
1367
1368       n_left_from -= 2;
1369       next[0] = next0;
1370       next[1] = next1;
1371       next += 2;
1372     }
1373
1374   while (n_left_from > 0)
1375     {
1376       vlib_buffer_t *b0;
1377       u32 next0;
1378       u32 sw_if_index0;
1379       ip4_header_t *ip0;
1380       ip_csum_t sum0;
1381       u32 new_addr0, old_addr0;
1382       u16 old_port0, new_port0;
1383       udp_header_t *udp0;
1384       tcp_header_t *tcp0;
1385       icmp46_header_t *icmp0;
1386       u32 rx_fib_index0;
1387       u32 proto0;
1388       snat_session_t *s0 = 0;
1389       clib_bihash_kv_8_8_t kv0, value0;
1390       u32 iph_offset0 = 0;
1391
1392       b0 = *b;
1393       b++;
1394       next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1395
1396       if (is_output_feature)
1397         iph_offset0 = vnet_buffer (b0)->ip.reass.save_rewrite_length;
1398
1399       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1400                               iph_offset0);
1401
1402       udp0 = ip4_next_header (ip0);
1403       tcp0 = (tcp_header_t *) udp0;
1404       icmp0 = (icmp46_header_t *) udp0;
1405
1406       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1407       rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1408                                sw_if_index0);
1409
1410       if (PREDICT_FALSE (ip0->ttl == 1))
1411         {
1412           vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1413           icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1414                                        ICMP4_time_exceeded_ttl_exceeded_in_transit,
1415                                        0);
1416           next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1417           goto trace0;
1418         }
1419
1420       proto0 = ip_proto_to_nat_proto (ip0->protocol);
1421
1422       /* Next configured feature, probably ip4-lookup */
1423       if (is_slow_path)
1424         {
1425           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1426             {
1427               if (nat_in2out_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
1428                 {
1429                   next0 = SNAT_IN2OUT_NEXT_DROP;
1430                   b0->error =
1431                     node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1432                 }
1433               vlib_increment_simple_counter (is_slow_path ? &sm->
1434                                              counters.slowpath.in2out.
1435                                              other : &sm->counters.fastpath.
1436                                              in2out.other, thread_index,
1437                                              sw_if_index0, 1);
1438               goto trace0;
1439             }
1440
1441           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1442             {
1443               next0 = icmp_in2out_slow_path
1444                 (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1445                  next0, now, thread_index, &s0);
1446               vlib_increment_simple_counter (is_slow_path ? &sm->
1447                                              counters.slowpath.in2out.
1448                                              icmp : &sm->counters.fastpath.
1449                                              in2out.icmp, thread_index,
1450                                              sw_if_index0, 1);
1451               goto trace0;
1452             }
1453         }
1454       else
1455         {
1456           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1457             {
1458               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1459               goto trace0;
1460             }
1461
1462           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1463             {
1464               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1465               goto trace0;
1466             }
1467         }
1468
1469       init_nat_k (&kv0, ip0->src_address,
1470                   vnet_buffer (b0)->ip.reass.l4_src_port, rx_fib_index0,
1471                   proto0);
1472
1473       if (clib_bihash_search_8_8
1474           (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1475         {
1476           if (is_slow_path)
1477             {
1478               if (is_output_feature)
1479                 {
1480                   if (PREDICT_FALSE
1481                       (nat_not_translate_output_feature
1482                        (sm, ip0, proto0,
1483                         vnet_buffer (b0)->ip.reass.l4_src_port,
1484                         vnet_buffer (b0)->ip.reass.l4_dst_port,
1485                         thread_index, sw_if_index0)))
1486                     goto trace0;
1487
1488                   /*
1489                    * Send DHCP packets to the ipv4 stack, or we won't
1490                    * be able to use dhcp client on the outside interface
1491                    */
1492                   if (PREDICT_FALSE
1493                       (proto0 == NAT_PROTOCOL_UDP
1494                        && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
1495                            clib_host_to_net_u16
1496                            (UDP_DST_PORT_dhcp_to_server))
1497                        && ip0->dst_address.as_u32 == 0xffffffff))
1498                     goto trace0;
1499                 }
1500               else
1501                 {
1502                   if (PREDICT_FALSE
1503                       (snat_not_translate
1504                        (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1505                         thread_index)))
1506                     goto trace0;
1507                 }
1508
1509               next0 =
1510                 slow_path (sm, b0, ip0, ip0->src_address,
1511                            vnet_buffer (b0)->ip.reass.l4_src_port,
1512                            rx_fib_index0, proto0, &s0, node, next0,
1513                            thread_index, now);
1514
1515               if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1516                 goto trace0;
1517
1518               if (PREDICT_FALSE (!s0))
1519                 goto trace0;
1520             }
1521           else
1522             {
1523               next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1524               goto trace0;
1525             }
1526         }
1527       else
1528         s0 =
1529           pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1530                              value0.value);
1531
1532       b0->flags |= VNET_BUFFER_F_IS_NATED;
1533
1534       old_addr0 = ip0->src_address.as_u32;
1535       ip0->src_address = s0->out2in.addr;
1536       new_addr0 = ip0->src_address.as_u32;
1537       if (!is_output_feature)
1538         vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1539
1540       sum0 = ip0->checksum;
1541       sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1542                              ip4_header_t, src_address /* changed member */ );
1543       ip0->checksum = ip_csum_fold (sum0);
1544
1545       if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1546         {
1547           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1548             {
1549               old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1550               new_port0 = udp0->src_port = s0->out2in.port;
1551               sum0 = tcp0->checksum;
1552               sum0 =
1553                 ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1554                                 dst_address /* changed member */ );
1555               sum0 =
1556                 ip_csum_update (sum0, old_port0, new_port0,
1557                                 ip4_header_t /* cheat */ ,
1558                                 length /* changed member */ );
1559               mss_clamping (sm->mss_clamping, tcp0, &sum0);
1560               tcp0->checksum = ip_csum_fold (sum0);
1561             }
1562           vlib_increment_simple_counter (is_slow_path ? &sm->
1563                                          counters.slowpath.in2out.tcp : &sm->
1564                                          counters.fastpath.in2out.tcp,
1565                                          thread_index, sw_if_index0, 1);
1566         }
1567       else
1568         {
1569           if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
1570             {
1571               udp0->src_port = s0->out2in.port;
1572               if (PREDICT_FALSE (udp0->checksum))
1573                 {
1574                   old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
1575                   new_port0 = udp0->src_port;
1576                   sum0 = udp0->checksum;
1577                   sum0 =
1578                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1579                                     dst_address /* changed member */ );
1580                   sum0 =
1581                     ip_csum_update (sum0, old_port0, new_port0,
1582                                     ip4_header_t /* cheat */ ,
1583                                     length /* changed member */ );
1584                   udp0->checksum = ip_csum_fold (sum0);
1585                 }
1586             }
1587           vlib_increment_simple_counter (is_slow_path ? &sm->
1588                                          counters.slowpath.in2out.udp : &sm->
1589                                          counters.fastpath.in2out.udp,
1590                                          thread_index, sw_if_index0, 1);
1591         }
1592
1593       /* Accounting */
1594       nat44_session_update_counters (s0, now,
1595                                      vlib_buffer_length_in_chain (vm, b0),
1596                                      thread_index);
1597       /* Per-user LRU list maintenance */
1598       nat44_session_update_lru (sm, s0, thread_index);
1599
1600     trace0:
1601       if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1602                          && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1603         {
1604           snat_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
1605           t->is_slow_path = is_slow_path;
1606           t->sw_if_index = sw_if_index0;
1607           t->next_index = next0;
1608           t->session_index = ~0;
1609           if (s0)
1610             t->session_index =
1611               s0 - sm->per_thread_data[thread_index].sessions;
1612         }
1613
1614       if (next0 == SNAT_IN2OUT_NEXT_DROP)
1615         {
1616           vlib_increment_simple_counter (is_slow_path ? &sm->
1617                                          counters.slowpath.in2out.
1618                                          drops : &sm->counters.fastpath.
1619                                          in2out.drops, thread_index,
1620                                          sw_if_index0, 1);
1621         }
1622
1623       n_left_from--;
1624       next[0] = next0;
1625       next++;
1626     }
1627
1628   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
1629                                frame->n_vectors);
1630   return frame->n_vectors;
1631 }
1632
1633 VLIB_NODE_FN (snat_in2out_node) (vlib_main_t * vm,
1634                                  vlib_node_runtime_t * node,
1635                                  vlib_frame_t * frame)
1636 {
1637   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1638                                      0);
1639 }
1640
1641 /* *INDENT-OFF* */
1642 VLIB_REGISTER_NODE (snat_in2out_node) = {
1643   .name = "nat44-in2out",
1644   .vector_size = sizeof (u32),
1645   .format_trace = format_snat_in2out_trace,
1646   .type = VLIB_NODE_TYPE_INTERNAL,
1647
1648   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1649   .error_strings = snat_in2out_error_strings,
1650
1651   .runtime_data_bytes = sizeof (snat_runtime_t),
1652
1653   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1654
1655   /* edit / add dispositions here */
1656   .next_nodes = {
1657     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1658     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1659     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1660     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1661   },
1662 };
1663 /* *INDENT-ON* */
1664
1665 VLIB_NODE_FN (snat_in2out_output_node) (vlib_main_t * vm,
1666                                         vlib_node_runtime_t * node,
1667                                         vlib_frame_t * frame)
1668 {
1669   return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1670                                      1);
1671 }
1672
1673 /* *INDENT-OFF* */
1674 VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1675   .name = "nat44-in2out-output",
1676   .vector_size = sizeof (u32),
1677   .format_trace = format_snat_in2out_trace,
1678   .type = VLIB_NODE_TYPE_INTERNAL,
1679
1680   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1681   .error_strings = snat_in2out_error_strings,
1682
1683   .runtime_data_bytes = sizeof (snat_runtime_t),
1684
1685   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1686
1687   /* edit / add dispositions here */
1688   .next_nodes = {
1689     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1690     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1691     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1692     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1693   },
1694 };
1695 /* *INDENT-ON* */
1696
1697 VLIB_NODE_FN (snat_in2out_slowpath_node) (vlib_main_t * vm,
1698                                           vlib_node_runtime_t * node,
1699                                           vlib_frame_t * frame)
1700 {
1701   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1702                                      0);
1703 }
1704
1705 /* *INDENT-OFF* */
1706 VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1707   .name = "nat44-in2out-slowpath",
1708   .vector_size = sizeof (u32),
1709   .format_trace = format_snat_in2out_trace,
1710   .type = VLIB_NODE_TYPE_INTERNAL,
1711
1712   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1713   .error_strings = snat_in2out_error_strings,
1714
1715   .runtime_data_bytes = sizeof (snat_runtime_t),
1716
1717   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1718
1719   /* edit / add dispositions here */
1720   .next_nodes = {
1721     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1722     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1723     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1724     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1725   },
1726 };
1727 /* *INDENT-ON* */
1728
1729 VLIB_NODE_FN (snat_in2out_output_slowpath_node) (vlib_main_t * vm,
1730                                                  vlib_node_runtime_t * node,
1731                                                  vlib_frame_t * frame)
1732 {
1733   return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1734                                      1);
1735 }
1736
1737 /* *INDENT-OFF* */
1738 VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1739   .name = "nat44-in2out-output-slowpath",
1740   .vector_size = sizeof (u32),
1741   .format_trace = format_snat_in2out_trace,
1742   .type = VLIB_NODE_TYPE_INTERNAL,
1743
1744   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1745   .error_strings = snat_in2out_error_strings,
1746
1747   .runtime_data_bytes = sizeof (snat_runtime_t),
1748
1749   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1750
1751   /* edit / add dispositions here */
1752   .next_nodes = {
1753     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1754     [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1755     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1756     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1757   },
1758 };
1759 /* *INDENT-ON* */
1760
1761 VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
1762                                       vlib_node_runtime_t * node,
1763                                       vlib_frame_t * frame)
1764 {
1765   u32 n_left_from, *from, *to_next;
1766   snat_in2out_next_t next_index;
1767   snat_main_t *sm = &snat_main;
1768   int is_hairpinning = 0;
1769
1770   from = vlib_frame_vector_args (frame);
1771   n_left_from = frame->n_vectors;
1772   next_index = node->cached_next_index;
1773
1774   while (n_left_from > 0)
1775     {
1776       u32 n_left_to_next;
1777
1778       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1779
1780       while (n_left_from > 0 && n_left_to_next > 0)
1781         {
1782           u32 bi0;
1783           vlib_buffer_t *b0;
1784           u32 next0;
1785           u32 sw_if_index0;
1786           ip4_header_t *ip0;
1787           ip_csum_t sum0;
1788           u32 new_addr0, old_addr0;
1789           u16 old_port0, new_port0;
1790           udp_header_t *udp0;
1791           tcp_header_t *tcp0;
1792           icmp46_header_t *icmp0;
1793           u32 proto0;
1794           u32 rx_fib_index0;
1795           ip4_address_t sm0_addr;
1796           u16 sm0_port;
1797           u32 sm0_fib_index;
1798
1799
1800           /* speculatively enqueue b0 to the current next frame */
1801           bi0 = from[0];
1802           to_next[0] = bi0;
1803           from += 1;
1804           to_next += 1;
1805           n_left_from -= 1;
1806           n_left_to_next -= 1;
1807
1808           b0 = vlib_get_buffer (vm, bi0);
1809           next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1810
1811           ip0 = vlib_buffer_get_current (b0);
1812           udp0 = ip4_next_header (ip0);
1813           tcp0 = (tcp_header_t *) udp0;
1814           icmp0 = (icmp46_header_t *) udp0;
1815
1816           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1817           rx_fib_index0 =
1818             ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
1819
1820           if (PREDICT_FALSE (ip0->ttl == 1))
1821             {
1822               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1823               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1824                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1825                                            0);
1826               next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1827               goto trace0;
1828             }
1829
1830           proto0 = ip_proto_to_nat_proto (ip0->protocol);
1831
1832           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
1833             goto trace0;
1834
1835           if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
1836             {
1837               next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
1838                                    rx_fib_index0, node, next0, ~0, 0, 0);
1839               goto trace0;
1840             }
1841
1842           if (snat_static_mapping_match
1843               (sm, ip0->src_address, udp0->src_port, rx_fib_index0, proto0,
1844                &sm0_addr, &sm0_port, &sm0_fib_index, 0, 0, 0, 0, 0, 0, 0))
1845             {
1846               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
1847               next0 = SNAT_IN2OUT_NEXT_DROP;
1848               goto trace0;
1849             }
1850
1851           new_addr0 = sm0_addr.as_u32;
1852           new_port0 = sm0_port;
1853           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0_fib_index;
1854           old_addr0 = ip0->src_address.as_u32;
1855           ip0->src_address.as_u32 = new_addr0;
1856
1857           sum0 = ip0->checksum;
1858           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1859                                  ip4_header_t,
1860                                  src_address /* changed member */ );
1861           ip0->checksum = ip_csum_fold (sum0);
1862
1863           if (PREDICT_FALSE (new_port0 != udp0->dst_port))
1864             {
1865               old_port0 = udp0->src_port;
1866               udp0->src_port = new_port0;
1867
1868               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1869                 {
1870                   sum0 = tcp0->checksum;
1871                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1872                                          ip4_header_t,
1873                                          dst_address /* changed member */ );
1874                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1875                                          ip4_header_t /* cheat */ ,
1876                                          length /* changed member */ );
1877                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1878                   tcp0->checksum = ip_csum_fold (sum0);
1879                 }
1880               else if (udp0->checksum)
1881                 {
1882                   sum0 = udp0->checksum;
1883                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1884                                          ip4_header_t,
1885                                          dst_address /* changed member */ );
1886                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1887                                          ip4_header_t /* cheat */ ,
1888                                          length /* changed member */ );
1889                   udp0->checksum = ip_csum_fold (sum0);
1890                 }
1891             }
1892           else
1893             {
1894               if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
1895                 {
1896                   sum0 = tcp0->checksum;
1897                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1898                                          ip4_header_t,
1899                                          dst_address /* changed member */ );
1900                   mss_clamping (sm->mss_clamping, tcp0, &sum0);
1901                   tcp0->checksum = ip_csum_fold (sum0);
1902                 }
1903               else if (udp0->checksum)
1904                 {
1905                   sum0 = udp0->checksum;
1906                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1907                                          ip4_header_t,
1908                                          dst_address /* changed member */ );
1909                   udp0->checksum = ip_csum_fold (sum0);
1910                 }
1911             }
1912
1913           /* Hairpinning */
1914           is_hairpinning =
1915             snat_hairpinning (vm, node, sm, b0, ip0, udp0, tcp0, proto0, 0,
1916                               0 /* do_trace */ );
1917
1918         trace0:
1919           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1920                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1921             {
1922               snat_in2out_trace_t *t =
1923                 vlib_add_trace (vm, node, b0, sizeof (*t));
1924               t->sw_if_index = sw_if_index0;
1925               t->next_index = next0;
1926               t->is_hairpinning = is_hairpinning;
1927             }
1928
1929           if (next0 != SNAT_IN2OUT_NEXT_DROP)
1930             {
1931
1932               vlib_increment_simple_counter (&sm->counters.fastpath.
1933                                              in2out.other, sw_if_index0,
1934                                              vm->thread_index, 1);
1935             }
1936
1937           /* verify speculative enqueue, maybe switch current next frame */
1938           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1939                                            to_next, n_left_to_next,
1940                                            bi0, next0);
1941         }
1942
1943       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1944     }
1945
1946   return frame->n_vectors;
1947 }
1948
1949
1950 /* *INDENT-OFF* */
1951 VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
1952   .name = "nat44-in2out-fast",
1953   .vector_size = sizeof (u32),
1954   .format_trace = format_snat_in2out_fast_trace,
1955   .type = VLIB_NODE_TYPE_INTERNAL,
1956
1957   .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1958   .error_strings = snat_in2out_error_strings,
1959
1960   .runtime_data_bytes = sizeof (snat_runtime_t),
1961
1962   .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1963
1964   /* edit / add dispositions here */
1965   .next_nodes = {
1966     [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1967     [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1968     [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1969     [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1970   },
1971 };
1972 /* *INDENT-ON* */
1973
1974 /*
1975  * fd.io coding-style-patch-verification: ON
1976  *
1977  * Local Variables:
1978  * eval: (c-set-style "gnu")
1979  * End:
1980  */