src/plugins/nat/nat44-ei/nat44_ei_hairpinning.c

   1 /*
   2  * nat44_ei.c - nat44 endpoint dependent plugin
   3  * * Copyright (c) 2020 Cisco and/or its affiliates.  * Licensed under the
   4  * Apache License, Version 2.0 (the "License"); you may not use this file
   5  * except in compliance with the License. You may obtain a copy of the License
   6  * at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  12  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  13  * License for the specific language governing permissions and limitations
  14  * under the License.
  15  */
  16
  17 #include <vlib/vlib.h>
  18 #include <vnet/vnet.h>
  19 #include <vnet/fib/ip4_fib.h>
  20
  21 #include <nat/nat44-ei/nat44_ei.h>
  22 #include <nat/nat44-ei/nat44_ei_inlines.h>
  23 #include <nat/nat44-ei/nat44_ei_hairpinning.h>
  24
  25 /* NAT buffer flags */
  26 #define NAT44_EI_FLAG_HAIRPINNING (1 << 0)
  27
  28 typedef enum
  29 {
  30   NAT44_EI_HAIRPIN_SRC_NEXT_DROP,
  31   NAT44_EI_HAIRPIN_SRC_NEXT_SNAT_IN2OUT,
  32   NAT44_EI_HAIRPIN_SRC_NEXT_SNAT_IN2OUT_WH,
  33   NAT44_EI_HAIRPIN_SRC_NEXT_INTERFACE_OUTPUT,
  34   NAT44_EI_HAIRPIN_SRC_N_NEXT,
  35 } nat44_ei_hairpin_src_next_t;
  36
  37 typedef enum
  38 {
  39   NAT44_EI_HAIRPIN_NEXT_LOOKUP,
  40   NAT44_EI_HAIRPIN_NEXT_DROP,
  41   NAT44_EI_HAIRPIN_NEXT_HANDOFF,
  42   NAT44_EI_HAIRPIN_N_NEXT,
  43 } nat44_ei_hairpin_next_t;
  44
  45 typedef struct
  46 {
  47   ip4_address_t addr;
  48   u16 port;
  49   u32 fib_index;
  50   u32 session_index;
  51 } nat44_ei_hairpin_trace_t;
  52
  53 static u8 *
  54 format_nat44_ei_hairpin_trace (u8 *s, va_list *args)
  55 {
  56   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  57   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  58   nat44_ei_hairpin_trace_t *t = va_arg (*args, nat44_ei_hairpin_trace_t *);
  59
  60   s = format (s, "new dst addr %U port %u fib-index %u", format_ip4_address,
  61               &t->addr, clib_net_to_host_u16 (t->port), t->fib_index);
  62   if (~0 == t->session_index)
  63     {
  64       s = format (s, " is-static-mapping");
  65     }
  66   else
  67     {
  68       s = format (s, " session-index %u", t->session_index);
  69     }
  70
  71   return s;
  72 }
  73
  74 extern vnet_feature_arc_registration_t vnet_feat_arc_ip4_local;
  75
  76 static_always_inline int
  77 nat44_ei_is_hairpinning (nat44_ei_main_t *nm, ip4_address_t *dst_addr)
  78 {
  79   nat44_ei_address_t *ap;
  80   clib_bihash_kv_8_8_t kv, value;
  81
  82   vec_foreach (ap, nm->addresses)
  83     {
  84       if (ap->addr.as_u32 == dst_addr->as_u32)
  85         return 1;
  86     }
  87
  88   init_nat_k (&kv, *dst_addr, 0, 0, 0);
  89   if (!clib_bihash_search_8_8 (&nm->static_mapping_by_external, &kv, &value))
  90     return 1;
  91
  92   return 0;
  93 }
  94
  95 #ifndef CLIB_MARCH_VARIANT
  96 void
  97 nat44_ei_hairpinning_sm_unknown_proto (nat44_ei_main_t *nm, vlib_buffer_t *b,
  98                                        ip4_header_t *ip)
  99 {
 100   clib_bihash_kv_8_8_t kv, value;
 101   nat44_ei_static_mapping_t *m;
 102   u32 old_addr, new_addr;
 103   ip_csum_t sum;
 104
 105   init_nat_k (&kv, ip->dst_address, 0, 0, 0);
 106   if (clib_bihash_search_8_8 (&nm->static_mapping_by_external, &kv, &value))
 107     return;
 108
 109   m = pool_elt_at_index (nm->static_mappings, value.value);
 110
 111   old_addr = ip->dst_address.as_u32;
 112   new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 113   sum = ip->checksum;
 114   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 115   ip->checksum = ip_csum_fold (sum);
 116
 117   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 118     vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 119 }
 120 #endif
 121
 122 #ifndef CLIB_MARCH_VARIANT
 123 int
 124 nat44_ei_hairpinning (vlib_main_t *vm, vlib_node_runtime_t *node,
 125                       nat44_ei_main_t *nm, u32 thread_index, vlib_buffer_t *b0,
 126                       ip4_header_t *ip0, udp_header_t *udp0,
 127                       tcp_header_t *tcp0, u32 proto0, int do_trace,
 128                       u32 *required_thread_index)
 129 {
 130   nat44_ei_session_t *s0 = NULL;
 131   clib_bihash_kv_8_8_t kv0, value0;
 132   ip_csum_t sum0;
 133   u32 new_dst_addr0 = 0, old_dst_addr0, si = ~0;
 134   u16 new_dst_port0 = ~0, old_dst_port0;
 135   int rv;
 136   ip4_address_t sm0_addr;
 137   u16 sm0_port;
 138   u32 sm0_fib_index;
 139   u32 old_sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_TX];
 140
 141   /* Check if destination is static mappings */
 142   if (!nat44_ei_static_mapping_match (
 143         ip0->dst_address, udp0->dst_port, nm->outside_fib_index, proto0,
 144         &sm0_addr, &sm0_port, &sm0_fib_index, 1 /* by external */, 0, 0))
 145     {
 146       new_dst_addr0 = sm0_addr.as_u32;
 147       new_dst_port0 = sm0_port;
 148       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0_fib_index;
 149     }
 150   /* or active session */
 151   else
 152     {
 153       init_nat_k (&kv0, ip0->dst_address, udp0->dst_port,
 154                   nm->outside_fib_index, proto0);
 155       rv = clib_bihash_search_8_8 (&nm->out2in, &kv0, &value0);
 156       if (rv)
 157         {
 158           rv = 0;
 159           goto trace;
 160         }
 161
 162       if (thread_index != nat_value_get_thread_index (&value0))
 163         {
 164           *required_thread_index = nat_value_get_thread_index (&value0);
 165           return 0;
 166         }
 167
 168       si = nat_value_get_session_index (&value0);
 169       s0 = pool_elt_at_index (nm->per_thread_data[thread_index].sessions, si);
 170       new_dst_addr0 = s0->in2out.addr.as_u32;
 171       new_dst_port0 = s0->in2out.port;
 172       vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 173     }
 174
 175   /* Check if anything has changed and if not, then return 0. This
 176      helps avoid infinite loop, repeating the three nodes
 177      nat44-hairpinning-->ip4-lookup-->ip4-local, in case nothing has
 178      changed. */
 179   old_dst_addr0 = ip0->dst_address.as_u32;
 180   old_dst_port0 = tcp0->dst;
 181   if (new_dst_addr0 == old_dst_addr0 && new_dst_port0 == old_dst_port0 &&
 182       vnet_buffer (b0)->sw_if_index[VLIB_TX] == old_sw_if_index)
 183     return 0;
 184
 185   /* Destination is behind the same NAT, use internal address and port */
 186   if (new_dst_addr0)
 187     {
 188       old_dst_addr0 = ip0->dst_address.as_u32;
 189       ip0->dst_address.as_u32 = new_dst_addr0;
 190       sum0 = ip0->checksum;
 191       sum0 = ip_csum_update (sum0, old_dst_addr0, new_dst_addr0, ip4_header_t,
 192                              dst_address);
 193       ip0->checksum = ip_csum_fold (sum0);
 194
 195       old_dst_port0 = tcp0->dst;
 196       if (PREDICT_TRUE (new_dst_port0 != old_dst_port0))
 197         {
 198           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 199             {
 200               tcp0->dst = new_dst_port0;
 201               sum0 = tcp0->checksum;
 202               sum0 = ip_csum_update (sum0, old_dst_addr0, new_dst_addr0,
 203                                      ip4_header_t, dst_address);
 204               sum0 = ip_csum_update (sum0, old_dst_port0, new_dst_port0,
 205                                      ip4_header_t /* cheat */, length);
 206               tcp0->checksum = ip_csum_fold (sum0);
 207             }
 208           else
 209             {
 210               udp0->dst_port = new_dst_port0;
 211               udp0->checksum = 0;
 212             }
 213         }
 214       else
 215         {
 216           if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 217             {
 218               sum0 = tcp0->checksum;
 219               sum0 = ip_csum_update (sum0, old_dst_addr0, new_dst_addr0,
 220                                      ip4_header_t, dst_address);
 221               tcp0->checksum = ip_csum_fold (sum0);
 222             }
 223         }
 224       rv = 1;
 225       goto trace;
 226     }
 227   rv = 0;
 228 trace:
 229   if (do_trace && PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
 230                                  (b0->flags & VLIB_BUFFER_IS_TRACED)))
 231     {
 232       nat44_ei_hairpin_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
 233       t->addr.as_u32 = new_dst_addr0;
 234       t->port = new_dst_port0;
 235       t->fib_index = vnet_buffer (b0)->sw_if_index[VLIB_TX];
 236       if (s0)
 237         {
 238           t->session_index = si;
 239         }
 240       else
 241         {
 242           t->session_index = ~0;
 243         }
 244     }
 245   return rv;
 246 }
 247 #endif
 248
 249 #ifndef CLIB_MARCH_VARIANT
 250 u32
 251 nat44_ei_icmp_hairpinning (nat44_ei_main_t *nm, vlib_buffer_t *b0,
 252                            u32 thread_index, ip4_header_t *ip0,
 253                            icmp46_header_t *icmp0, u32 *required_thread_index)
 254 {
 255   clib_bihash_kv_8_8_t kv0, value0;
 256   u32 old_dst_addr0, new_dst_addr0;
 257   u32 old_addr0, new_addr0;
 258   u16 old_port0, new_port0;
 259   u16 old_checksum0, new_checksum0;
 260   u32 si, ti = 0;
 261   ip_csum_t sum0;
 262   nat44_ei_session_t *s0;
 263   nat44_ei_static_mapping_t *m0;
 264
 265   if (icmp_type_is_error_message (
 266         vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags))
 267     {
 268       ip4_header_t *inner_ip0 = 0;
 269       tcp_udp_header_t *l4_header = 0;
 270
 271       inner_ip0 = (ip4_header_t *) ((icmp_echo_header_t *) (icmp0 + 1) + 1);
 272       l4_header = ip4_next_header (inner_ip0);
 273       u32 protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
 274
 275       if (protocol != NAT_PROTOCOL_TCP && protocol != NAT_PROTOCOL_UDP)
 276         return 1;
 277
 278       init_nat_k (&kv0, ip0->dst_address, l4_header->src_port,
 279                   nm->outside_fib_index, protocol);
 280       if (clib_bihash_search_8_8 (&nm->out2in, &kv0, &value0))
 281         return 1;
 282       ti = nat_value_get_thread_index (&value0);
 283       if (ti != thread_index)
 284         {
 285           *required_thread_index = ti;
 286           return 1;
 287         }
 288       si = nat_value_get_session_index (&value0);
 289       s0 = pool_elt_at_index (nm->per_thread_data[ti].sessions, si);
 290       new_dst_addr0 = s0->in2out.addr.as_u32;
 291       vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 292
 293       /* update inner source IP address */
 294       old_addr0 = inner_ip0->src_address.as_u32;
 295       inner_ip0->src_address.as_u32 = new_dst_addr0;
 296       new_addr0 = inner_ip0->src_address.as_u32;
 297       sum0 = icmp0->checksum;
 298       sum0 =
 299         ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, src_address);
 300       icmp0->checksum = ip_csum_fold (sum0);
 301
 302       /* update inner IP header checksum */
 303       old_checksum0 = inner_ip0->checksum;
 304       sum0 = inner_ip0->checksum;
 305       sum0 =
 306         ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, src_address);
 307       inner_ip0->checksum = ip_csum_fold (sum0);
 308       new_checksum0 = inner_ip0->checksum;
 309       sum0 = icmp0->checksum;
 310       sum0 = ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
 311                              checksum);
 312       icmp0->checksum = ip_csum_fold (sum0);
 313
 314       /* update inner source port */
 315       old_port0 = l4_header->src_port;
 316       l4_header->src_port = s0->in2out.port;
 317       new_port0 = l4_header->src_port;
 318       sum0 = icmp0->checksum;
 319       sum0 = ip_csum_update (sum0, old_port0, new_port0, tcp_udp_header_t,
 320                              src_port);
 321       icmp0->checksum = ip_csum_fold (sum0);
 322     }
 323   else
 324     {
 325       init_nat_k (&kv0, ip0->dst_address, 0, nm->outside_fib_index, 0);
 326       if (clib_bihash_search_8_8 (&nm->static_mapping_by_external, &kv0,
 327                                   &value0))
 328         {
 329           icmp_echo_header_t *echo0 = (icmp_echo_header_t *) (icmp0 + 1);
 330           u16 icmp_id0 = echo0->identifier;
 331           init_nat_k (&kv0, ip0->dst_address, icmp_id0, nm->outside_fib_index,
 332                       NAT_PROTOCOL_ICMP);
 333           int rv = clib_bihash_search_8_8 (&nm->out2in, &kv0, &value0);
 334           if (!rv)
 335             {
 336               ti = nat_value_get_thread_index (&value0);
 337               if (ti != thread_index)
 338                 {
 339                   *required_thread_index = ti;
 340                   return 1;
 341                 }
 342               si = nat_value_get_session_index (&value0);
 343               s0 = pool_elt_at_index (nm->per_thread_data[ti].sessions, si);
 344               new_dst_addr0 = s0->in2out.addr.as_u32;
 345               vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 346               echo0->identifier = s0->in2out.port;
 347               sum0 = icmp0->checksum;
 348               sum0 = ip_csum_update (sum0, icmp_id0, s0->in2out.port,
 349                                      icmp_echo_header_t, identifier);
 350               icmp0->checksum = ip_csum_fold (sum0);
 351               goto change_addr;
 352             }
 353
 354           return 1;
 355         }
 356
 357       m0 = pool_elt_at_index (nm->static_mappings, value0.value);
 358
 359       new_dst_addr0 = m0->local_addr.as_u32;
 360       if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
 361         vnet_buffer (b0)->sw_if_index[VLIB_TX] = m0->fib_index;
 362     }
 363 change_addr:
 364   /* Destination is behind the same NAT, use internal address and port */
 365   if (new_dst_addr0)
 366     {
 367       old_dst_addr0 = ip0->dst_address.as_u32;
 368       ip0->dst_address.as_u32 = new_dst_addr0;
 369       sum0 = ip0->checksum;
 370       sum0 = ip_csum_update (sum0, old_dst_addr0, new_dst_addr0, ip4_header_t,
 371                              dst_address);
 372       ip0->checksum = ip_csum_fold (sum0);
 373     }
 374   return 0;
 375 }
 376 #endif
 377
 378 void nat44_ei_hairpinning_unknown_proto (nat44_ei_main_t *nm, vlib_buffer_t *b,
 379                                          ip4_header_t *ip);
 380
 381 #ifndef CLIB_MARCH_VARIANT
 382 void
 383 nat44_ei_hairpinning_unknown_proto (nat44_ei_main_t *nm, vlib_buffer_t *b,
 384                                     ip4_header_t *ip)
 385 {
 386   clib_bihash_kv_8_8_t kv, value;
 387   nat44_ei_static_mapping_t *m;
 388   u32 old_addr, new_addr;
 389   ip_csum_t sum;
 390
 391   init_nat_k (&kv, ip->dst_address, 0, 0, 0);
 392   if (clib_bihash_search_8_8 (&nm->static_mapping_by_external, &kv, &value))
 393     return;
 394
 395   m = pool_elt_at_index (nm->static_mappings, value.value);
 396
 397   old_addr = ip->dst_address.as_u32;
 398   new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 399   sum = ip->checksum;
 400   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 401   ip->checksum = ip_csum_fold (sum);
 402
 403   if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
 404     vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
 405 }
 406 #endif
 407
 408 VLIB_NODE_FN (nat44_ei_hairpin_src_node)
 409 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 410 {
 411   u32 n_left_from, *from, *to_next;
 412   nat44_ei_hairpin_src_next_t next_index;
 413   nat44_ei_main_t *nm = &nat44_ei_main;
 414
 415   from = vlib_frame_vector_args (frame);
 416   n_left_from = frame->n_vectors;
 417   next_index = node->cached_next_index;
 418
 419   while (n_left_from > 0)
 420     {
 421       u32 n_left_to_next;
 422
 423       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 424
 425       while (n_left_from > 0 && n_left_to_next > 0)
 426         {
 427           u32 bi0;
 428           vlib_buffer_t *b0;
 429           u32 next0;
 430           nat44_ei_interface_t *i;
 431           u32 rx_sw_if_index0;
 432           u32 tx_sw_if_index0;
 433
 434           /* speculatively enqueue b0 to the current next frame */
 435           bi0 = from[0];
 436           to_next[0] = bi0;
 437           from += 1;
 438           to_next += 1;
 439           n_left_from -= 1;
 440           n_left_to_next -= 1;
 441
 442           b0 = vlib_get_buffer (vm, bi0);
 443           rx_sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 444           tx_sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
 445
 446           pool_foreach (i, nm->output_feature_interfaces)
 447             {
 448               /* Only packets from NAT inside interface */
 449               if ((nat44_ei_interface_is_inside (i)) &&
 450                   (rx_sw_if_index0 == i->sw_if_index))
 451                 {
 452                   if (PREDICT_FALSE ((vnet_buffer (b0)->snat.flags) &
 453                                      NAT44_EI_FLAG_HAIRPINNING))
 454                     {
 455                       if (PREDICT_TRUE (nm->num_workers > 1))
 456                         {
 457                           next0 = NAT44_EI_HAIRPIN_SRC_NEXT_SNAT_IN2OUT_WH;
 458                           goto skip_feature_next;
 459                         }
 460                       else
 461                         {
 462                           next0 = NAT44_EI_HAIRPIN_SRC_NEXT_SNAT_IN2OUT;
 463                           goto skip_feature_next;
 464                         }
 465                     }
 466                   break;
 467                 }
 468             }
 469
 470           vnet_feature_next (&next0, b0);
 471         skip_feature_next:
 472
 473           if (next0 != NAT44_EI_HAIRPIN_SRC_NEXT_DROP)
 474             {
 475               vlib_increment_simple_counter (&nm->counters.hairpinning,
 476                                              vm->thread_index, tx_sw_if_index0,
 477                                              1);
 478             }
 479
 480           /* verify speculative enqueue, maybe switch current next frame */
 481           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 482                                            n_left_to_next, bi0, next0);
 483         }
 484
 485       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 486     }
 487
 488   return frame->n_vectors;
 489 }
 490
 491 VLIB_NODE_FN (nat44_ei_hairpin_dst_node)
 492 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 493 {
 494   u32 n_left_from, *from, *to_next;
 495   u32 thread_index = vm->thread_index;
 496   nat44_ei_hairpin_next_t next_index;
 497   nat44_ei_main_t *nm = &nat44_ei_main;
 498
 499   from = vlib_frame_vector_args (frame);
 500   n_left_from = frame->n_vectors;
 501   next_index = node->cached_next_index;
 502
 503   while (n_left_from > 0)
 504     {
 505       u32 n_left_to_next;
 506
 507       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 508
 509       while (n_left_from > 0 && n_left_to_next > 0)
 510         {
 511           u32 bi0;
 512           vlib_buffer_t *b0;
 513           u32 next0;
 514           ip4_header_t *ip0;
 515           u32 proto0;
 516           u32 sw_if_index0;
 517           u32 required_thread_index = thread_index;
 518
 519           /* speculatively enqueue b0 to the current next frame */
 520           bi0 = from[0];
 521           to_next[0] = bi0;
 522           from += 1;
 523           to_next += 1;
 524           n_left_from -= 1;
 525           n_left_to_next -= 1;
 526
 527           b0 = vlib_get_buffer (vm, bi0);
 528           next0 = NAT44_EI_HAIRPIN_NEXT_LOOKUP;
 529           ip0 = vlib_buffer_get_current (b0);
 530           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 531
 532           proto0 = ip_proto_to_nat_proto (ip0->protocol);
 533
 534           vnet_buffer (b0)->snat.flags = 0;
 535           if (PREDICT_FALSE (nat44_ei_is_hairpinning (nm, &ip0->dst_address)))
 536             {
 537               if (proto0 == NAT_PROTOCOL_TCP || proto0 == NAT_PROTOCOL_UDP)
 538                 {
 539                   udp_header_t *udp0 = ip4_next_header (ip0);
 540                   tcp_header_t *tcp0 = (tcp_header_t *) udp0;
 541
 542                   nat44_ei_hairpinning (vm, node, nm, thread_index, b0, ip0,
 543                                         udp0, tcp0, proto0, 1 /* do_trace */,
 544                                         &required_thread_index);
 545                 }
 546               else if (proto0 == NAT_PROTOCOL_ICMP)
 547                 {
 548                   icmp46_header_t *icmp0 = ip4_next_header (ip0);
 549
 550                   nat44_ei_icmp_hairpinning (nm, b0, thread_index, ip0, icmp0,
 551                                              &required_thread_index);
 552                 }
 553               else
 554                 {
 555                   nat44_ei_hairpinning_unknown_proto (nm, b0, ip0);
 556                 }
 557
 558               vnet_buffer (b0)->snat.flags = NAT44_EI_FLAG_HAIRPINNING;
 559             }
 560
 561           if (thread_index != required_thread_index)
 562             {
 563               vnet_buffer (b0)->snat.required_thread_index =
 564                 required_thread_index;
 565               next0 = NAT44_EI_HAIRPIN_NEXT_HANDOFF;
 566             }
 567
 568           if (next0 != NAT44_EI_HAIRPIN_NEXT_DROP)
 569             {
 570               vlib_increment_simple_counter (
 571                 &nm->counters.hairpinning, vm->thread_index, sw_if_index0, 1);
 572             }
 573
 574           /* verify speculative enqueue, maybe switch current next frame */
 575           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 576                                            n_left_to_next, bi0, next0);
 577         }
 578
 579       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 580     }
 581
 582   return frame->n_vectors;
 583 }
 584
 585 VLIB_NODE_FN (nat44_ei_hairpinning_node)
 586 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 587 {
 588   u32 n_left_from, *from, *to_next;
 589   u32 thread_index = vm->thread_index;
 590   nat44_ei_hairpin_next_t next_index;
 591   nat44_ei_main_t *nm = &nat44_ei_main;
 592   vnet_feature_main_t *fm = &feature_main;
 593   u8 arc_index = vnet_feat_arc_ip4_local.feature_arc_index;
 594   vnet_feature_config_main_t *cm = &fm->feature_config_mains[arc_index];
 595
 596   from = vlib_frame_vector_args (frame);
 597   n_left_from = frame->n_vectors;
 598   next_index = node->cached_next_index;
 599
 600   while (n_left_from > 0)
 601     {
 602       u32 n_left_to_next;
 603
 604       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 605
 606       while (n_left_from > 0 && n_left_to_next > 0)
 607         {
 608           u32 bi0;
 609           vlib_buffer_t *b0;
 610           u32 next0;
 611           ip4_header_t *ip0;
 612           u32 proto0;
 613           udp_header_t *udp0;
 614           tcp_header_t *tcp0;
 615           u32 sw_if_index0;
 616           u32 required_thread_index = thread_index;
 617
 618           /* speculatively enqueue b0 to the current next frame */
 619           bi0 = from[0];
 620           to_next[0] = bi0;
 621           from += 1;
 622           to_next += 1;
 623           n_left_from -= 1;
 624           n_left_to_next -= 1;
 625
 626           b0 = vlib_get_buffer (vm, bi0);
 627           ip0 = vlib_buffer_get_current (b0);
 628           udp0 = ip4_next_header (ip0);
 629           tcp0 = (tcp_header_t *) udp0;
 630           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 631
 632           proto0 = ip_proto_to_nat_proto (ip0->protocol);
 633           int next0_resolved = 0;
 634
 635           if (nat44_ei_hairpinning (vm, node, nm, thread_index, b0, ip0, udp0,
 636                                     tcp0, proto0, 1 /* do_trace */,
 637                                     &required_thread_index))
 638             {
 639               next0 = NAT44_EI_HAIRPIN_NEXT_LOOKUP;
 640               next0_resolved = 1;
 641             }
 642
 643           if (thread_index != required_thread_index)
 644             {
 645               vnet_buffer (b0)->snat.required_thread_index =
 646                 required_thread_index;
 647               next0 = NAT44_EI_HAIRPIN_NEXT_HANDOFF;
 648               next0_resolved = 1;
 649             }
 650
 651           if (!next0_resolved)
 652             vnet_get_config_data (&cm->config_main, &b0->current_config_index,
 653                                   &next0, 0);
 654
 655           if (next0 != NAT44_EI_HAIRPIN_NEXT_DROP)
 656             {
 657               vlib_increment_simple_counter (
 658                 &nm->counters.hairpinning, vm->thread_index, sw_if_index0, 1);
 659             }
 660
 661           /* verify speculative enqueue, maybe switch current next frame */
 662           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 663                                            n_left_to_next, bi0, next0);
 664         }
 665
 666       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 667     }
 668
 669   return frame->n_vectors;
 670 }
 671
 672 VLIB_NODE_FN (nat44_ei_hairpinning_dst_handoff_node)
 673 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 674 {
 675   return nat44_ei_hairpinning_handoff_fn_inline (
 676     vm, node, frame, nat44_ei_main.hairpin_dst_fq_index);
 677 }
 678
 679 VLIB_NODE_FN (nat44_ei_hairpinning_handoff_node)
 680 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 681 {
 682   return nat44_ei_hairpinning_handoff_fn_inline (
 683     vm, node, frame, nat44_ei_main.hairpinning_fq_index);
 684 }
 685
 686 VLIB_REGISTER_NODE (nat44_ei_hairpinning_dst_handoff_node) = {
 687   .name = "nat44-ei-hairpin-dst-handoff",
 688   .vector_size = sizeof (u32),
 689   .n_errors = ARRAY_LEN(nat44_ei_hairpinning_handoff_error_strings),
 690   .error_strings = nat44_ei_hairpinning_handoff_error_strings,
 691   .format_trace = format_nat44_ei_hairpinning_handoff_trace,
 692
 693   .n_next_nodes = 1,
 694
 695   .next_nodes = {
 696     [0] = "error-drop",
 697   },
 698 };
 699
 700 VLIB_REGISTER_NODE (nat44_ei_hairpinning_handoff_node) = {
 701   .name = "nat44-ei-hairpinning-handoff",
 702   .vector_size = sizeof (u32),
 703   .n_errors = ARRAY_LEN(nat44_ei_hairpinning_handoff_error_strings),
 704   .error_strings = nat44_ei_hairpinning_handoff_error_strings,
 705   .format_trace = format_nat44_ei_hairpinning_handoff_trace,
 706
 707   .n_next_nodes = 1,
 708
 709   .next_nodes = {
 710     [0] = "error-drop",
 711   },
 712 };
 713
 714 VLIB_REGISTER_NODE (nat44_ei_hairpin_src_node) = {
 715   .name = "nat44-ei-hairpin-src",
 716   .vector_size = sizeof (u32),
 717   .type = VLIB_NODE_TYPE_INTERNAL,
 718   .n_next_nodes = NAT44_EI_HAIRPIN_SRC_N_NEXT,
 719   .next_nodes = {
 720      [NAT44_EI_HAIRPIN_SRC_NEXT_DROP] = "error-drop",
 721      [NAT44_EI_HAIRPIN_SRC_NEXT_SNAT_IN2OUT] = "nat44-ei-in2out-output",
 722      [NAT44_EI_HAIRPIN_SRC_NEXT_INTERFACE_OUTPUT] = "interface-output",
 723      [NAT44_EI_HAIRPIN_SRC_NEXT_SNAT_IN2OUT_WH] = "nat44-ei-in2out-output-worker-handoff",
 724   },
 725 };
 726
 727 VLIB_REGISTER_NODE (nat44_ei_hairpin_dst_node) = {
 728   .name = "nat44-ei-hairpin-dst",
 729   .vector_size = sizeof (u32),
 730   .type = VLIB_NODE_TYPE_INTERNAL,
 731   .format_trace = format_nat44_ei_hairpin_trace,
 732   .n_next_nodes = NAT44_EI_HAIRPIN_N_NEXT,
 733   .next_nodes = {
 734     [NAT44_EI_HAIRPIN_NEXT_DROP] = "error-drop",
 735     [NAT44_EI_HAIRPIN_NEXT_LOOKUP] = "ip4-lookup",
 736     [NAT44_EI_HAIRPIN_NEXT_HANDOFF] = "nat44-ei-hairpin-dst-handoff",
 737   },
 738 };
 739
 740 VLIB_REGISTER_NODE (nat44_ei_hairpinning_node) = {
 741   .name = "nat44-ei-hairpinning",
 742   .vector_size = sizeof (u32),
 743   .type = VLIB_NODE_TYPE_INTERNAL,
 744   .format_trace = format_nat44_ei_hairpin_trace,
 745   .n_next_nodes = NAT44_EI_HAIRPIN_N_NEXT,
 746   .next_nodes = {
 747     [NAT44_EI_HAIRPIN_NEXT_DROP] = "error-drop",
 748     [NAT44_EI_HAIRPIN_NEXT_LOOKUP] = "ip4-lookup",
 749     [NAT44_EI_HAIRPIN_NEXT_HANDOFF] = "nat44-ei-hairpinning-handoff",
 750   },
 751 };
 752
 753 /*
 754  * fd.io coding-style-patch-verification: ON
 755  *
 756  * Local Variables:
 757  * eval: (c-set-style "gnu")
 758  * End:
 759  */