src/plugins/nat/nat.h

   1
   2 /*
   3  * nat.h - NAT plugin definitions
   4  *
   5  * Copyright (c) 2016 Cisco and/or its affiliates.
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at:
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18 #ifndef __included_nat_h__
  19 #define __included_nat_h__
  20
  21 #include <vnet/vnet.h>
  22 #include <vnet/ip/ip.h>
  23 #include <vnet/ethernet/ethernet.h>
  24 #include <vnet/ip/icmp46_packet.h>
  25 #include <vnet/api_errno.h>
  26 #include <vppinfra/bihash_8_8.h>
  27 #include <vppinfra/bihash_16_8.h>
  28 #include <vppinfra/dlist.h>
  29 #include <vppinfra/error.h>
  30 #include <vlibapi/api.h>
  31 #include <vlib/log.h>
  32
  33
  34 #define SNAT_UDP_TIMEOUT 300
  35 #define SNAT_TCP_TRANSITORY_TIMEOUT 240
  36 #define SNAT_TCP_ESTABLISHED_TIMEOUT 7440
  37 #define SNAT_ICMP_TIMEOUT 60
  38
  39 #define NAT_FQ_NELTS 64
  40
  41 #define SNAT_FLAG_HAIRPINNING (1 << 0)
  42
  43 /* Key */
  44 typedef struct {
  45   union
  46   {
  47     struct
  48     {
  49       ip4_address_t addr;
  50       u16 port;
  51       u16 protocol:3,
  52         fib_index:13;
  53     };
  54     u64 as_u64;
  55   };
  56 } snat_session_key_t;
  57
  58 typedef struct {
  59   union
  60   {
  61     struct
  62     {
  63       ip4_address_t l_addr;
  64       ip4_address_t r_addr;
  65       u32 proto:8,
  66           fib_index:24;
  67       u16 l_port;
  68       u16 r_port;
  69     };
  70     u64 as_u64[2];
  71   };
  72 } nat_ed_ses_key_t;
  73
  74 typedef struct {
  75   union
  76   {
  77     struct
  78     {
  79       ip4_address_t ext_host_addr;
  80       u16 ext_host_port;
  81       u16 out_port;
  82     };
  83     u64 as_u64;
  84   };
  85 } snat_det_out_key_t;
  86
  87 typedef struct {
  88   union
  89   {
  90     struct
  91     {
  92       ip4_address_t addr;
  93       u32 fib_index;
  94     };
  95     u64 as_u64;
  96   };
  97 } snat_user_key_t;
  98
  99
 100 #define foreach_snat_protocol \
 101   _(UDP, 0, udp, "udp")       \
 102   _(TCP, 1, tcp, "tcp")       \
 103   _(ICMP, 2, icmp, "icmp")
 104
 105 typedef enum {
 106 #define _(N, i, n, s) SNAT_PROTOCOL_##N = i,
 107   foreach_snat_protocol
 108 #undef _
 109 } snat_protocol_t;
 110
 111
 112 #define foreach_snat_session_state          \
 113   _(0, UNKNOWN, "unknown")                 \
 114   _(1, UDP_ACTIVE, "udp-active")           \
 115   _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
 116   _(3, TCP_ESTABLISHED, "tcp-established") \
 117   _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
 118   _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
 119   _(6, TCP_CLOSING, "tcp-closing")         \
 120   _(7, TCP_LAST_ACK, "tcp-last-ack")       \
 121   _(8, TCP_CLOSED, "tcp-closed")           \
 122   _(9, ICMP_ACTIVE, "icmp-active")
 123
 124 typedef enum {
 125 #define _(v, N, s) SNAT_SESSION_##N = v,
 126   foreach_snat_session_state
 127 #undef _
 128 } snat_session_state_t;
 129
 130 #define NAT44_SES_I2O_FIN 1
 131 #define NAT44_SES_O2I_FIN 2
 132 #define NAT44_SES_I2O_FIN_ACK 4
 133 #define NAT44_SES_O2I_FIN_ACK 8
 134 #define NAT44_SES_I2O_SYN 16
 135 #define NAT44_SES_O2I_SYN 32
 136
 137 #define nat44_is_ses_closed(s) s->state == 0xf
 138
 139 #define SNAT_SESSION_FLAG_STATIC_MAPPING       1
 140 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO        2
 141 #define SNAT_SESSION_FLAG_LOAD_BALANCING       4
 142 #define SNAT_SESSION_FLAG_TWICE_NAT            8
 143 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT   16
 144 #define SNAT_SESSION_FLAG_FWD_BYPASS           32
 145 #define SNAT_SESSION_FLAG_AFFINITY             64
 146
 147 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
 148 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
 149
 150 typedef CLIB_PACKED(struct {
 151   snat_session_key_t out2in;    /* 0-15 */
 152
 153   snat_session_key_t in2out;    /* 16-31 */
 154
 155   u32 flags;                    /* 32-35 */
 156
 157   /* per-user translations */
 158   u32 per_user_index;           /* 36-39 */
 159
 160   u32 per_user_list_head_index; /* 40-43 */
 161
 162   /* Last heard timer */
 163   f64 last_heard;               /* 44-51 */
 164
 165   u64 total_bytes;              /* 52-59 */
 166
 167   u32 total_pkts;               /* 60-63 */
 168
 169   /* Outside address */
 170   u32 outside_address_index;    /* 64-67 */
 171
 172   /* External host address and port */
 173   ip4_address_t ext_host_addr;  /* 68-71 */
 174   u16 ext_host_port;            /* 72-73 */
 175
 176   /* External host address and port after translation */
 177   ip4_address_t ext_host_nat_addr; /* 74-77 */
 178   u16 ext_host_nat_port;           /* 78-79 */
 179
 180   /* TCP session state */
 181   u8 state;
 182   u32 i2o_fin_seq;
 183   u32 o2i_fin_seq;
 184 }) snat_session_t;
 185
 186
 187 typedef struct {
 188   ip4_address_t addr;
 189   u32 fib_index;
 190   u32 sessions_per_user_list_head_index;
 191   u32 nsessions;
 192   u32 nstaticsessions;
 193 } snat_user_t;
 194
 195 typedef struct {
 196   ip4_address_t addr;
 197   u32 fib_index;
 198 #define _(N, i, n, s) \
 199   u16 busy_##n##_ports; \
 200   u16 * busy_##n##_ports_per_thread; \
 201   uword * busy_##n##_port_bitmap;
 202   foreach_snat_protocol
 203 #undef _
 204 } snat_address_t;
 205
 206 typedef struct {
 207   u32 fib_index;
 208   u32 refcount;
 209 } nat_outside_fib_t;
 210
 211 typedef struct {
 212   u16 in_port;
 213   snat_det_out_key_t out;
 214   u8 state;
 215   u32 expire;
 216 } snat_det_session_t;
 217
 218 typedef struct {
 219   ip4_address_t in_addr;
 220   u8 in_plen;
 221   ip4_address_t out_addr;
 222   u8 out_plen;
 223   u32 sharing_ratio;
 224   u16 ports_per_host;
 225   u32 ses_num;
 226   /* vector of sessions */
 227   snat_det_session_t * sessions;
 228 } snat_det_map_t;
 229
 230 typedef struct {
 231   ip4_address_t addr;
 232   u16 port;
 233   u8 probability;
 234   u8 prefix;
 235   u32 vrf_id;
 236   u32 fib_index;
 237 } nat44_lb_addr_port_t;
 238
 239 typedef enum {
 240   TWICE_NAT_DISABLED,
 241   TWICE_NAT,
 242   TWICE_NAT_SELF,
 243 } twice_nat_type_t;
 244
 245 typedef enum {
 246   NO_LB_NAT,
 247   LB_NAT,
 248   AFFINITY_LB_NAT,
 249 } lb_nat_type_t;
 250
 251 typedef struct {
 252   ip4_address_t local_addr;
 253   ip4_address_t external_addr;
 254   u16 local_port;
 255   u16 external_port;
 256   u8 addr_only;
 257   twice_nat_type_t twice_nat;
 258   u8 out2in_only;
 259   u32 vrf_id;
 260   u32 fib_index;
 261   snat_protocol_t proto;
 262   u32 affinity;
 263   u32 *workers;
 264   u8 *tag;
 265   nat44_lb_addr_port_t *locals;
 266   u32 affinity_per_service_list_head_index;
 267 } snat_static_mapping_t;
 268
 269 typedef struct {
 270   u32 sw_if_index;
 271   u8 flags;
 272 } snat_interface_t;
 273
 274 typedef struct {
 275   ip4_address_t l_addr;
 276   u16 l_port;
 277   u16 e_port;
 278   u32 sw_if_index;
 279   u32 vrf_id;
 280   snat_protocol_t proto;
 281   int addr_only;
 282   int twice_nat;
 283   int is_add;
 284   u8 *tag;
 285 } snat_static_map_resolve_t;
 286
 287 typedef struct {
 288   /* Main lookup tables */
 289   clib_bihash_8_8_t out2in;
 290   clib_bihash_8_8_t in2out;
 291
 292   /* Endpoint dependent sessions lookup tables */
 293   clib_bihash_16_8_t out2in_ed;
 294   clib_bihash_16_8_t in2out_ed;
 295
 296   /* Find-a-user => src address lookup */
 297   clib_bihash_8_8_t user_hash;
 298
 299   /* User pool */
 300   snat_user_t * users;
 301
 302   /* Session pool */
 303   snat_session_t * sessions;
 304
 305   /* Pool of doubly-linked list elements */
 306   dlist_elt_t * list_pool;
 307
 308   u32 snat_thread_index;
 309 } snat_main_per_thread_data_t;
 310
 311 struct snat_main_s;
 312
 313 typedef u32 snat_icmp_match_function_t (struct snat_main_s *sm,
 314                                         vlib_node_runtime_t *node,
 315                                         u32 thread_index,
 316                                         vlib_buffer_t *b0,
 317                                         ip4_header_t *ip0,
 318                                         u8 *p_proto,
 319                                         snat_session_key_t *p_value,
 320                                         u8 *p_dont_translate,
 321                                         void *d,
 322                                         void *e);
 323
 324 typedef u32 (snat_get_worker_function_t) (ip4_header_t * ip, u32 rx_fib_index);
 325
 326 typedef int nat_alloc_out_addr_and_port_function_t (snat_address_t * addresses,
 327                                                     u32 fib_index,
 328                                                     u32 thread_index,
 329                                                     snat_session_key_t * k,
 330                                                     u32 * address_indexp,
 331                                                     u16 port_per_thread,
 332                                                     u32 snat_thread_index);
 333
 334 typedef struct snat_main_s {
 335   snat_icmp_match_function_t * icmp_match_in2out_cb;
 336   snat_icmp_match_function_t * icmp_match_out2in_cb;
 337
 338   u32 num_workers;
 339   u32 first_worker_index;
 340   u32 * workers;
 341   snat_get_worker_function_t * worker_in2out_cb;
 342   snat_get_worker_function_t * worker_out2in_cb;
 343   u16 port_per_thread;
 344   u32 num_snat_thread;
 345
 346   /* Per thread data */
 347   snat_main_per_thread_data_t * per_thread_data;
 348
 349   /* Find a static mapping by local */
 350   clib_bihash_8_8_t static_mapping_by_local;
 351
 352   /* Find a static mapping by external */
 353   clib_bihash_8_8_t static_mapping_by_external;
 354
 355   /* Static mapping pool */
 356   snat_static_mapping_t * static_mappings;
 357
 358   /* Interface pool */
 359   snat_interface_t * interfaces;
 360   snat_interface_t * output_feature_interfaces;
 361
 362   /* Vector of outside addresses */
 363   snat_address_t * addresses;
 364   nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
 365   u8 psid_offset;
 366   u8 psid_length;
 367   u16 psid;
 368
 369   /* vector of outside fibs */
 370   nat_outside_fib_t * outside_fibs;
 371
 372   /* Vector of twice NAT addresses for extenal hosts */
 373   snat_address_t * twice_nat_addresses;
 374
 375   /* sw_if_indices whose intfc addresses should be auto-added */
 376   u32 * auto_add_sw_if_indices;
 377   u32 * auto_add_sw_if_indices_twice_nat;
 378
 379   /* vector of interface address static mappings to resolve. */
 380   snat_static_map_resolve_t *to_resolve;
 381
 382   /* Randomize port allocation order */
 383   u32 random_seed;
 384
 385   /* Worker handoff index */
 386   u32 fq_in2out_index;
 387   u32 fq_in2out_output_index;
 388   u32 fq_out2in_index;
 389
 390   /* in2out and out2in node index */
 391   u32 in2out_node_index;
 392   u32 in2out_output_node_index;
 393   u32 out2in_node_index;
 394   u32 error_node_index;
 395
 396   /* Deterministic NAT */
 397   snat_det_map_t * det_maps;
 398
 399   /* If forwarding is enabled */
 400   u8 forwarding_enabled;
 401
 402   /* Config parameters */
 403   u8 static_mapping_only;
 404   u8 static_mapping_connection_tracking;
 405   u8 deterministic;
 406   u8 out2in_dpo;
 407   u8 endpoint_dependent;
 408   u32 translation_buckets;
 409   u32 translation_memory_size;
 410   u32 max_translations;
 411   u32 user_buckets;
 412   u32 user_memory_size;
 413   u32 max_translations_per_user;
 414   u32 outside_vrf_id;
 415   u32 outside_fib_index;
 416   u32 inside_vrf_id;
 417   u32 inside_fib_index;
 418
 419   /* values of various timeouts */
 420   u32 udp_timeout;
 421   u32 tcp_established_timeout;
 422   u32 tcp_transitory_timeout;
 423   u32 icmp_timeout;
 424
 425   /* API message ID base */
 426   u16 msg_id_base;
 427
 428   /* log class */
 429   vlib_log_class_t log_class;
 430
 431   /* convenience */
 432   vlib_main_t * vlib_main;
 433   vnet_main_t * vnet_main;
 434   ip4_main_t * ip4_main;
 435   ip_lookup_main_t * ip4_lookup_main;
 436   api_main_t * api_main;
 437 } snat_main_t;
 438
 439 typedef struct {
 440   u32 thread_index;
 441   f64 now;
 442 } nat44_is_idle_session_ctx_t;
 443
 444 extern snat_main_t snat_main;
 445 extern vlib_node_registration_t snat_in2out_node;
 446 extern vlib_node_registration_t snat_in2out_output_node;
 447 extern vlib_node_registration_t snat_out2in_node;
 448 extern vlib_node_registration_t snat_in2out_fast_node;
 449 extern vlib_node_registration_t snat_out2in_fast_node;
 450 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
 451 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
 452 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
 453 extern vlib_node_registration_t snat_det_in2out_node;
 454 extern vlib_node_registration_t snat_det_out2in_node;
 455 extern vlib_node_registration_t snat_hairpin_dst_node;
 456 extern vlib_node_registration_t snat_hairpin_src_node;
 457 extern vlib_node_registration_t nat44_ed_in2out_node;
 458 extern vlib_node_registration_t nat44_ed_in2out_output_node;
 459 extern vlib_node_registration_t nat44_ed_out2in_node;
 460 extern vlib_node_registration_t nat44_ed_hairpin_dst_node;
 461 extern vlib_node_registration_t nat44_ed_hairpin_src_node;
 462 extern vlib_node_registration_t nat44_ed_in2out_worker_handoff_node;
 463 extern vlib_node_registration_t nat44_ed_in2out_output_worker_handoff_node;
 464 extern vlib_node_registration_t nat44_ed_out2in_worker_handoff_node;
 465
 466 void snat_free_outside_address_and_port (snat_address_t * addresses,
 467                                          u32 thread_index,
 468                                          snat_session_key_t * k);
 469
 470 int snat_alloc_outside_address_and_port (snat_address_t * addresses,
 471                                          u32 fib_index,
 472                                          u32 thread_index,
 473                                          snat_session_key_t * k,
 474                                          u32 * address_indexp,
 475                                          u16 port_per_thread,
 476                                          u32 snat_thread_index);
 477
 478 int snat_static_mapping_match (snat_main_t * sm,
 479                                snat_session_key_t match,
 480                                snat_session_key_t * mapping,
 481                                u8 by_external,
 482                                u8 *is_addr_only,
 483                                twice_nat_type_t *twice_nat,
 484                                lb_nat_type_t *lb,
 485                                ip4_address_t * ext_host_addr);
 486
 487 void snat_add_del_addr_to_fib (ip4_address_t * addr,
 488                                u8 p_len,
 489                                u32 sw_if_index,
 490                                int is_add);
 491
 492 format_function_t format_snat_user;
 493 format_function_t format_snat_static_mapping;
 494 format_function_t format_snat_static_map_to_resolve;
 495 format_function_t format_snat_session;
 496 format_function_t format_det_map_ses;
 497
 498 typedef struct {
 499   u32 cached_sw_if_index;
 500   u32 cached_ip4_address;
 501 } snat_runtime_t;
 502
 503 /** \brief Check if SNAT session is created from static mapping.
 504     @param s SNAT session
 505     @return 1 if SNAT session is created from static mapping otherwise 0
 506 */
 507 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
 508
 509 /** \brief Check if SNAT session for unknown protocol.
 510     @param s SNAT session
 511     @return 1 if SNAT session for unknown protocol otherwise 0
 512 */
 513 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
 514
 515 /** \brief Check if NAT session is twice NAT.
 516     @param s NAT session
 517     @return 1 if NAT session is twice NAT
 518 */
 519 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
 520
 521 /** \brief Check if NAT session is load-balancing.
 522     @param s NAT session
 523     @return 1 if NAT session is load-balancing
 524 */
 525 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
 526
 527 /** \brief Check if NAT session is forwarding bypass.
 528     @param s NAT session
 529     @return 1 if NAT session is load-balancing
 530 */
 531 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
 532
 533 /** \brief Check if NAT session is endpoint dependent.
 534     @param s NAT session
 535     @return 1 if NAT session is endpoint dependent
 536 */
 537 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
 538
 539 /** \brief Check if NAT session has affinity record.
 540     @param s NAT session
 541     @return 1 if NAT session has affinity record
 542 */
 543 #define is_affinity_sessions(s) (s->flags & SNAT_SESSION_FLAG_AFFINITY)
 544
 545 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
 546 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
 547
 548 #define nat_log_err(...) \
 549   vlib_log(VLIB_LOG_LEVEL_ERR, snat_main.log_class, __VA_ARGS__)
 550 #define nat_log_warn(...) \
 551   vlib_log(VLIB_LOG_LEVEL_WARNING, snat_main.log_class, __VA_ARGS__)
 552 #define nat_log_notice(...) \
 553   vlib_log(VLIB_LOG_LEVEL_NOTICE, snat_main.log_class, __VA_ARGS__)
 554 #define nat_log_info(...) \
 555   vlib_log(VLIB_LOG_LEVEL_INFO, snat_main.log_class, __VA_ARGS__)
 556 #define nat_log_debug(...)\
 557   vlib_log(VLIB_LOG_LEVEL_DEBUG, snat_main.log_class, __VA_ARGS__)
 558
 559 /*
 560  * Why is this here? Because we don't need to touch this layer to
 561  * simply reply to an icmp. We need to change id to a unique
 562  * value to NAT an echo request/reply.
 563  */
 564
 565 typedef struct {
 566   u16 identifier;
 567   u16 sequence;
 568 } icmp_echo_header_t;
 569
 570 typedef struct {
 571   u16 src_port, dst_port;
 572 } tcp_udp_header_t;
 573
 574 u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
 575                            u32 thread_index, vlib_buffer_t *b0,
 576                            ip4_header_t *ip0, u8 *p_proto,
 577                            snat_session_key_t *p_value,
 578                            u8 *p_dont_translate, void *d, void *e);
 579 u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
 580                            u32 thread_index, vlib_buffer_t *b0,
 581                            ip4_header_t *ip0, u8 *p_proto,
 582                            snat_session_key_t *p_value,
 583                            u8 *p_dont_translate, void *d, void *e);
 584 u32 icmp_match_in2out_det(snat_main_t *sm, vlib_node_runtime_t *node,
 585                           u32 thread_index, vlib_buffer_t *b0,
 586                           ip4_header_t *ip0, u8 *p_proto,
 587                           snat_session_key_t *p_value,
 588                           u8 *p_dont_translate, void *d, void *e);
 589 u32 icmp_match_in2out_ed(snat_main_t *sm, vlib_node_runtime_t *node,
 590                          u32 thread_index, vlib_buffer_t *b0,
 591                          ip4_header_t *ip0, u8 *p_proto,
 592                          snat_session_key_t *p_value,
 593                          u8 *p_dont_translate, void *d, void *e);
 594 u32 icmp_match_out2in_fast(snat_main_t *sm, vlib_node_runtime_t *node,
 595                            u32 thread_index, vlib_buffer_t *b0,
 596                            ip4_header_t *ip0, u8 *p_proto,
 597                            snat_session_key_t *p_value,
 598                            u8 *p_dont_translate, void *d, void *e);
 599 u32 icmp_match_out2in_slow(snat_main_t *sm, vlib_node_runtime_t *node,
 600                            u32 thread_index, vlib_buffer_t *b0,
 601                            ip4_header_t *ip0, u8 *p_proto,
 602                            snat_session_key_t *p_value,
 603                            u8 *p_dont_translate, void *d, void *e);
 604 u32 icmp_match_out2in_det(snat_main_t *sm, vlib_node_runtime_t *node,
 605                           u32 thread_index, vlib_buffer_t *b0,
 606                           ip4_header_t *ip0, u8 *p_proto,
 607                           snat_session_key_t *p_value,
 608                           u8 *p_dont_translate, void *d, void *e);
 609 u32 icmp_match_out2in_ed(snat_main_t *sm, vlib_node_runtime_t *node,
 610                          u32 thread_index, vlib_buffer_t *b0,
 611                          ip4_header_t *ip0, u8 *p_proto,
 612                          snat_session_key_t *p_value,
 613                          u8 *p_dont_translate, void *d, void *e);
 614 void increment_v4_address(ip4_address_t * a);
 615 int snat_add_address(snat_main_t *sm, ip4_address_t *addr, u32 vrf_id,
 616                      u8 twice_nat);
 617 int snat_del_address(snat_main_t *sm, ip4_address_t addr, u8 delete_sm,
 618                      u8 twice_nat);
 619 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
 620 int snat_add_static_mapping(ip4_address_t l_addr, ip4_address_t e_addr,
 621                             u16 l_port, u16 e_port, u32 vrf_id, int addr_only,
 622                             u32 sw_if_index, snat_protocol_t proto, int is_add,
 623                             twice_nat_type_t twice_nat, u8 out2in_only,
 624                             u8 *tag);
 625 clib_error_t * snat_api_init(vlib_main_t * vm, snat_main_t * sm);
 626 int snat_set_workers (uword * bitmap);
 627 int snat_interface_add_del(u32 sw_if_index, u8 is_inside, int is_del);
 628 int snat_interface_add_del_output_feature(u32 sw_if_index, u8 is_inside,
 629                                           int is_del);
 630 int snat_add_interface_address(snat_main_t *sm, u32 sw_if_index, int is_del,
 631                                u8 twice_nat);
 632 uword unformat_snat_protocol(unformat_input_t * input, va_list * args);
 633 u8 * format_snat_protocol(u8 * s, va_list * args);
 634 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
 635                                      snat_protocol_t proto,
 636                                      nat44_lb_addr_port_t *locals, u8 is_add,
 637                                      twice_nat_type_t twice_nat, u8 out2in_only,
 638                                      u8 *tag, u32 affinity);
 639 int nat44_del_session (snat_main_t *sm, ip4_address_t *addr, u16 port,
 640                        snat_protocol_t proto, u32 vrf_id, int is_in);
 641 int nat44_del_ed_session (snat_main_t *sm, ip4_address_t *addr, u16 port,
 642                           ip4_address_t *eh_addr, u16 eh_port, u8 proto,
 643                           u32 vrf_id, int is_in);
 644 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
 645                             u32 thread_index);
 646 snat_user_t * nat_user_get_or_create (snat_main_t *sm, ip4_address_t *addr,
 647                                       u32 fib_index, u32 thread_index);
 648 snat_session_t * nat_session_alloc_or_recycle (snat_main_t *sm, snat_user_t *u,
 649                                                u32 thread_index);
 650 snat_session_t * nat_ed_session_alloc (snat_main_t *sm, snat_user_t *u,
 651                                        u32 thread_index);
 652 void nat_set_alloc_addr_and_port_mape (u16 psid, u16 psid_offset,
 653                                        u16 psid_length);
 654 void nat_set_alloc_addr_and_port_default (void);
 655 int nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t *kv, void *arg);
 656 int nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t *kv, void *arg);
 657 int nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t *kv, void *arg);
 658 int nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t *kv, void *arg);
 659
 660 #endif /* __included_snat_h__ */