src/plugins/nat/nat.h

   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 nat.c
  17  * NAT plugin global declarations
  18  */
  19 #ifndef __included_nat_h__
  20 #define __included_nat_h__
  21
  22 #include <vnet/vnet.h>
  23 #include <vnet/ip/ip.h>
  24 #include <vnet/ethernet/ethernet.h>
  25 #include <vnet/ip/icmp46_packet.h>
  26 #include <vnet/api_errno.h>
  27 #include <vnet/fib/fib_source.h>
  28 #include <vppinfra/elog.h>
  29 #include <vppinfra/bihash_8_8.h>
  30 #include <vppinfra/bihash_16_8.h>
  31 #include <vppinfra/dlist.h>
  32 #include <vppinfra/error.h>
  33 #include <vlibapi/api.h>
  34 #include <vlib/log.h>
  35 #include <vppinfra/bihash_16_8.h>
  36 #include <nat/lib/lib.h>
  37 #include <nat/lib/inlines.h>
  38
  39 /* default session timeouts */
  40 #define SNAT_UDP_TIMEOUT 300
  41 #define SNAT_TCP_TRANSITORY_TIMEOUT 240
  42 #define SNAT_TCP_ESTABLISHED_TIMEOUT 7440
  43 #define SNAT_ICMP_TIMEOUT 60
  44
  45 /* number of worker handoff frame queue elements */
  46 #define NAT_FQ_NELTS 64
  47
  48 /* NAT buffer flags */
  49 #define SNAT_FLAG_HAIRPINNING (1 << 0)
  50
  51 /* NAT44 API Configuration flags */
  52 #define foreach_nat44_config_flag  \
  53   _(0x00, IS_ENDPOINT_INDEPENDENT) \
  54   _(0x01, IS_ENDPOINT_DEPENDENT)   \
  55   _(0x02, IS_STATIC_MAPPING_ONLY)  \
  56   _(0x04, IS_CONNECTION_TRACKING)  \
  57   _(0x08, IS_OUT2IN_DPO)
  58
  59 typedef enum nat44_config_flags_t_
  60 {
  61 #define _(n,f) NAT44_API_##f = n,
  62   foreach_nat44_config_flag
  63 #undef _
  64 } nat44_config_flags_t;
  65
  66 typedef struct
  67 {
  68   /* nat44 plugin features */
  69   u8 static_mapping_only;
  70   u8 connection_tracking;
  71   u8 endpoint_dependent;
  72   u8 out2in_dpo;
  73
  74   u32 inside_vrf;
  75   u32 outside_vrf;
  76
  77   /* maximum number of users */
  78   u32 users;
  79   u32 user_memory;
  80
  81   /* maximum number of sessions */
  82   u32 sessions;
  83   u32 session_memory;
  84
  85   /* maximum number of ssessions per user */
  86   u32 user_sessions;
  87 } nat44_config_t;
  88
  89 typedef enum
  90 {
  91   NAT_NEXT_DROP,
  92   NAT_NEXT_ICMP_ERROR,
  93   NAT_NEXT_IN2OUT_ED_FAST_PATH,
  94   NAT_NEXT_IN2OUT_ED_SLOW_PATH,
  95   NAT_NEXT_IN2OUT_ED_OUTPUT_FAST_PATH,
  96   NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH,
  97   NAT_NEXT_OUT2IN_ED_FAST_PATH,
  98   NAT_NEXT_OUT2IN_ED_SLOW_PATH,
  99   NAT_NEXT_IN2OUT_CLASSIFY,
 100   NAT_NEXT_OUT2IN_CLASSIFY,
 101   NAT_N_NEXT,
 102 } nat_next_t;
 103
 104 typedef struct
 105 {
 106   u32 next_index;
 107   u32 arc_next_index;
 108 } nat_pre_trace_t;
 109
 110 /* user (internal host) key */
 111 typedef struct
 112 {
 113   union
 114   {
 115     struct
 116     {
 117       ip4_address_t addr;
 118       u32 fib_index;
 119     };
 120     u64 as_u64;
 121   };
 122 } snat_user_key_t;
 123
 124 /* External address and port allocation modes */
 125 #define foreach_nat_addr_and_port_alloc_alg \
 126   _(0, DEFAULT, "default")         \
 127   _(1, MAPE, "map-e")              \
 128   _(2, RANGE, "port-range")
 129
 130 typedef enum
 131 {
 132 #define _(v, N, s) NAT_ADDR_AND_PORT_ALLOC_ALG_##N = v,
 133   foreach_nat_addr_and_port_alloc_alg
 134 #undef _
 135 } nat_addr_and_port_alloc_alg_t;
 136
 137 /* Session state */
 138 #define foreach_snat_session_state          \
 139   _(0, UNKNOWN, "unknown")                 \
 140   _(1, UDP_ACTIVE, "udp-active")           \
 141   _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
 142   _(3, TCP_ESTABLISHED, "tcp-established") \
 143   _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
 144   _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
 145   _(6, TCP_CLOSING, "tcp-closing")         \
 146   _(7, TCP_LAST_ACK, "tcp-last-ack")       \
 147   _(8, TCP_CLOSED, "tcp-closed")           \
 148   _(9, ICMP_ACTIVE, "icmp-active")
 149
 150 typedef enum
 151 {
 152 #define _(v, N, s) SNAT_SESSION_##N = v,
 153   foreach_snat_session_state
 154 #undef _
 155 } snat_session_state_t;
 156
 157 #define foreach_nat_in2out_ed_error                     \
 158 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 159 _(OUT_OF_PORTS, "out of ports")                         \
 160 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 161 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 162 _(NON_SYN, "non-SYN packet try to create session")      \
 163 _(TCP_CLOSED, "drops due to TCP in transitory timeout")
 164
 165 typedef enum
 166 {
 167 #define _(sym,str) NAT_IN2OUT_ED_ERROR_##sym,
 168   foreach_nat_in2out_ed_error
 169 #undef _
 170     NAT_IN2OUT_ED_N_ERROR,
 171 } nat_in2out_ed_error_t;
 172
 173 #define foreach_nat_out2in_ed_error                     \
 174 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 175 _(OUT_OF_PORTS, "out of ports")                         \
 176 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 177 _(NO_TRANSLATION, "no translation")                     \
 178 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 179 _(MAX_USER_SESS_EXCEEDED, "max user sessions exceeded") \
 180 _(CANNOT_CREATE_USER, "cannot create NAT user")         \
 181 _(NON_SYN, "non-SYN packet try to create session")      \
 182 _(TCP_CLOSED, "drops due to TCP in transitory timeout")
 183
 184 typedef enum
 185 {
 186 #define _(sym,str) NAT_OUT2IN_ED_ERROR_##sym,
 187   foreach_nat_out2in_ed_error
 188 #undef _
 189     NAT_OUT2IN_ED_N_ERROR,
 190 } nat_out2in_ed_error_t;
 191
 192
 193 /* Endpoint dependent TCP session state */
 194 #define NAT44_SES_I2O_FIN 1
 195 #define NAT44_SES_O2I_FIN 2
 196 #define NAT44_SES_I2O_FIN_ACK 4
 197 #define NAT44_SES_O2I_FIN_ACK 8
 198 #define NAT44_SES_I2O_SYN 16
 199 #define NAT44_SES_O2I_SYN 32
 200 #define NAT44_SES_RST     64
 201
 202 /* Session flags */
 203 #define SNAT_SESSION_FLAG_STATIC_MAPPING       1
 204 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO        2
 205 #define SNAT_SESSION_FLAG_LOAD_BALANCING       4
 206 #define SNAT_SESSION_FLAG_TWICE_NAT            8
 207 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT   16
 208 #define SNAT_SESSION_FLAG_FWD_BYPASS           32
 209 #define SNAT_SESSION_FLAG_AFFINITY             64
 210 #define SNAT_SESSION_FLAG_OUTPUT_FEATURE       128
 211 #define SNAT_SESSION_FLAG_EXACT_ADDRESS        256
 212
 213 /* NAT interface flags */
 214 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
 215 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
 216
 217 /* Static mapping flags */
 218 #define NAT_STATIC_MAPPING_FLAG_ADDR_ONLY      1
 219 #define NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY    2
 220 #define NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT   4
 221 #define NAT_STATIC_MAPPING_FLAG_LB             8
 222 #define NAT_STATIC_MAPPING_FLAG_EXACT_ADDRESS  16
 223
 224 /* *INDENT-OFF* */
 225 typedef CLIB_PACKED(struct
 226 {
 227   // number of sessions in this vrf
 228   u32 ses_count;
 229
 230   u32 rx_fib_index;
 231   u32 tx_fib_index;
 232
 233   // is this vrf expired
 234   u8 expired;
 235 }) per_vrf_sessions_t;
 236 /* *INDENT-ON* */
 237
 238 /* *INDENT-OFF* */
 239 typedef CLIB_PACKED(struct
 240 {
 241   /* Outside network tuple */
 242   struct
 243   {
 244     ip4_address_t addr;
 245     u32 fib_index;
 246     u16 port;
 247   } out2in;
 248
 249   /* Inside network tuple */
 250   struct
 251   {
 252     ip4_address_t addr;
 253     u32 fib_index;
 254     u16 port;
 255   } in2out;
 256
 257   nat_protocol_t nat_proto;
 258
 259   /* Flags */
 260   u32 flags;
 261
 262   /* Per-user translations */
 263   u32 per_user_index;
 264   u32 per_user_list_head_index;
 265
 266   /* head of LRU list in which this session is tracked */
 267   u32 lru_head_index;
 268   /* index in global LRU list */
 269   u32 lru_index;
 270   f64 last_lru_update;
 271
 272   /* Last heard timer */
 273   f64 last_heard;
 274
 275   /* Last HA refresh */
 276   f64 ha_last_refreshed;
 277
 278   /* Counters */
 279   u64 total_bytes;
 280   u32 total_pkts;
 281
 282   /* External host address and port */
 283   ip4_address_t ext_host_addr;
 284   u16 ext_host_port;
 285
 286   /* External host address and port after translation */
 287   ip4_address_t ext_host_nat_addr;
 288   u16 ext_host_nat_port;
 289
 290   /* TCP session state */
 291   u8 state;
 292   u32 i2o_fin_seq;
 293   u32 o2i_fin_seq;
 294   u64 tcp_closed_timestamp;
 295
 296   /* user index */
 297   u32 user_index;
 298
 299   /* per vrf sessions index */
 300   u32 per_vrf_sessions_index;
 301
 302 }) snat_session_t;
 303 /* *INDENT-ON* */
 304
 305 typedef struct
 306 {
 307   ip4_address_t addr;
 308   u32 fib_index;
 309   u32 sessions_per_user_list_head_index;
 310   u32 nsessions;
 311   u32 nstaticsessions;
 312 } snat_user_t;
 313
 314 typedef struct
 315 {
 316   ip4_address_t addr;
 317   u32 fib_index;
 318 /* *INDENT-OFF* */
 319 #define _(N, i, n, s) \
 320   u32 busy_##n##_ports; \
 321   u32 * busy_##n##_ports_per_thread; \
 322   u32 busy_##n##_port_refcounts[65535];
 323   foreach_nat_protocol
 324 #undef _
 325 /* *INDENT-ON* */
 326 } snat_address_t;
 327
 328 typedef struct
 329 {
 330   u32 fib_index;
 331   u32 ref_count;
 332 } nat_fib_t;
 333
 334 typedef struct
 335 {
 336   u32 fib_index;
 337   u32 refcount;
 338 } nat_outside_fib_t;
 339
 340 typedef struct
 341 {
 342   /* backend IP address */
 343   ip4_address_t addr;
 344   /* backend port number */
 345   u16 port;
 346   /* probability of the backend to be randomly matched */
 347   u8 probability;
 348   u8 prefix;
 349   /* backend FIB table */
 350   u32 vrf_id;
 351   u32 fib_index;
 352 } nat44_lb_addr_port_t;
 353
 354 typedef enum
 355 {
 356   /* twice-nat disabled */
 357   TWICE_NAT_DISABLED,
 358   /* twice-nat enabled */
 359   TWICE_NAT,
 360   /* twice-nat only when src IP equals dst IP after translation */
 361   TWICE_NAT_SELF,
 362 } twice_nat_type_t;
 363
 364 typedef enum
 365 {
 366   /* no load-balancing */
 367   NO_LB_NAT,
 368   /* load-balancing */
 369   LB_NAT,
 370   /* load-balancing with affinity */
 371   AFFINITY_LB_NAT,
 372 } lb_nat_type_t;
 373
 374 typedef struct
 375 {
 376   /* prefered pool address */
 377   ip4_address_t pool_addr;
 378   /* local IP address */
 379   ip4_address_t local_addr;
 380   /* external IP address */
 381   ip4_address_t external_addr;
 382   /* local port */
 383   u16 local_port;
 384   /* external port */
 385   u16 external_port;
 386   /* is twice-nat */
 387   twice_nat_type_t twice_nat;
 388   /* local FIB table */
 389   u32 vrf_id;
 390   u32 fib_index;
 391   /* protocol */
 392   nat_protocol_t proto;
 393   /* 0 = disabled, otherwise client IP affinity sticky time in seconds */
 394   u32 affinity;
 395   /* worker threads used by backends/local host */
 396   u32 *workers;
 397   /* opaque string tag */
 398   u8 *tag;
 399   /* backends for load-balancing mode */
 400   nat44_lb_addr_port_t *locals;
 401   /* affinity per service lis */
 402   u32 affinity_per_service_list_head_index;
 403   /* flags */
 404   u32 flags;
 405 } snat_static_mapping_t;
 406
 407 typedef struct
 408 {
 409   u32 sw_if_index;
 410   u8 flags;
 411 } snat_interface_t;
 412
 413 typedef struct
 414 {
 415   ip4_address_t l_addr;
 416   ip4_address_t pool_addr;
 417   u16 l_port;
 418   u16 e_port;
 419   u32 sw_if_index;
 420   u32 vrf_id;
 421   nat_protocol_t proto;
 422   u32 flags;
 423   int addr_only;
 424   int twice_nat;
 425   int is_add;
 426   int out2in_only;
 427   int identity_nat;
 428   int exact;
 429   u8 *tag;
 430 } snat_static_map_resolve_t;
 431
 432 typedef struct
 433 {
 434   /* Main lookup tables */
 435   clib_bihash_8_8_t out2in;
 436   clib_bihash_8_8_t in2out;
 437
 438   /* Endpoint dependent sessions lookup tables */
 439   clib_bihash_16_8_t in2out_ed;
 440
 441   /* Find-a-user => src address lookup */
 442   clib_bihash_8_8_t user_hash;
 443
 444   /* User pool */
 445   snat_user_t *users;
 446
 447   /* Session pool */
 448   snat_session_t *sessions;
 449
 450   /* Pool of doubly-linked list elements */
 451   dlist_elt_t *list_pool;
 452
 453   /* LRU session list - head is stale, tail is fresh */
 454   dlist_elt_t *lru_pool;
 455   u32 tcp_trans_lru_head_index;
 456   u32 tcp_estab_lru_head_index;
 457   u32 udp_lru_head_index;
 458   u32 icmp_lru_head_index;
 459   u32 unk_proto_lru_head_index;
 460
 461   /* NAT thread index */
 462   u32 snat_thread_index;
 463
 464   /* real thread index */
 465   u32 thread_index;
 466
 467   per_vrf_sessions_t *per_vrf_sessions_vec;
 468
 469 } snat_main_per_thread_data_t;
 470
 471 struct snat_main_s;
 472
 473 /* ICMP session match function */
 474 typedef u32 (snat_icmp_match_function_t) (struct snat_main_s * sm,
 475                                           vlib_node_runtime_t * node,
 476                                           u32 thread_index,
 477                                           vlib_buffer_t * b0,
 478                                           ip4_header_t * ip0,
 479                                           ip4_address_t * addr,
 480                                           u16 * port,
 481                                           u32 * fib_index,
 482                                           nat_protocol_t * proto,
 483                                           void *d, void *e,
 484                                           u8 * dont_translate);
 485
 486 /* Return worker thread index for given packet */
 487 typedef u32 (snat_get_worker_in2out_function_t) (ip4_header_t * ip,
 488                                                  u32 rx_fib_index,
 489                                                  u8 is_output);
 490
 491 typedef u32 (snat_get_worker_out2in_function_t) (vlib_buffer_t * b,
 492                                                  ip4_header_t * ip,
 493                                                  u32 rx_fib_index,
 494                                                  u8 is_output);
 495
 496 /* NAT address and port allocation function */
 497 typedef int (nat_alloc_out_addr_and_port_function_t) (snat_address_t *
 498                                                       addresses,
 499                                                       u32 fib_index,
 500                                                       u32 thread_index,
 501                                                       nat_protocol_t proto,
 502                                                       ip4_address_t * addr,
 503                                                       u16 * port,
 504                                                       u16 port_per_thread,
 505                                                       u32 snat_thread_index);
 506
 507 #define foreach_nat_counter _ (tcp) _ (udp) _ (icmp) _ (other) _ (drops)
 508
 509 typedef struct snat_main_s
 510 {
 511   /* ICMP session match functions */
 512   snat_icmp_match_function_t *icmp_match_in2out_cb;
 513   snat_icmp_match_function_t *icmp_match_out2in_cb;
 514
 515   /* Thread settings */
 516   u32 num_workers;
 517   u32 first_worker_index;
 518   u32 *workers;
 519   snat_get_worker_in2out_function_t *worker_in2out_cb;
 520   snat_get_worker_out2in_function_t *worker_out2in_cb;
 521   u16 port_per_thread;
 522
 523   /* Per thread data */
 524   snat_main_per_thread_data_t *per_thread_data;
 525
 526   /* Find a static mapping by local */
 527   clib_bihash_8_8_t static_mapping_by_local;
 528
 529   /* Find a static mapping by external */
 530   clib_bihash_8_8_t static_mapping_by_external;
 531
 532   /* Static mapping pool */
 533   snat_static_mapping_t *static_mappings;
 534
 535   /* Endpoint-dependent out2in mappings */
 536   clib_bihash_16_8_t out2in_ed;
 537
 538   /* Interface pool */
 539   snat_interface_t *interfaces;
 540   snat_interface_t *output_feature_interfaces;
 541
 542   /* Vector of outside addresses */
 543   snat_address_t *addresses;
 544   /* Address and port allocation function */
 545   nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
 546   /* Address and port allocation type */
 547   nat_addr_and_port_alloc_alg_t addr_and_port_alloc_alg;
 548   /* Port set parameters (MAP-E) */
 549   u8 psid_offset;
 550   u8 psid_length;
 551   u16 psid;
 552   /* Port range parameters */
 553   u16 start_port;
 554   u16 end_port;
 555
 556   /* vector of fibs */
 557   nat_fib_t *fibs;
 558
 559   /* vector of outside fibs */
 560   nat_outside_fib_t *outside_fibs;
 561
 562   /* Vector of twice NAT addresses for external hosts */
 563   snat_address_t *twice_nat_addresses;
 564
 565   /* sw_if_indices whose intfc addresses should be auto-added */
 566   u32 *auto_add_sw_if_indices;
 567   u32 *auto_add_sw_if_indices_twice_nat;
 568
 569   /* vector of interface address static mappings to resolve. */
 570   snat_static_map_resolve_t *to_resolve;
 571
 572   /* Randomize port allocation order */
 573   u32 random_seed;
 574
 575   /* Worker handoff frame-queue index */
 576   u32 fq_in2out_index;
 577   u32 fq_in2out_output_index;
 578   u32 fq_out2in_index;
 579
 580   /* node indexes */
 581   u32 error_node_index;
 582
 583   /* handoff fq nodes  */
 584   u32 handoff_out2in_index;
 585   u32 handoff_in2out_index;
 586   u32 handoff_in2out_output_index;
 587
 588   /* respect feature arc nodes */
 589   u32 pre_out2in_node_index;
 590   u32 pre_in2out_node_index;
 591
 592   u32 out2in_node_index;
 593   u32 in2out_node_index;
 594   u32 in2out_output_node_index;
 595
 596   u32 in2out_fast_node_index;
 597   u32 in2out_slowpath_node_index;
 598   u32 in2out_slowpath_output_node_index;
 599   u32 out2in_fast_node_index;
 600
 601   u32 ei_out2in_node_index;
 602   u32 ei_in2out_node_index;
 603   u32 ei_in2out_output_node_index;
 604
 605   u32 ed_out2in_node_index;
 606   u32 ed_in2out_node_index;
 607   u32 ed_in2out_output_node_index;
 608
 609   u32 ed_in2out_slowpath_node_index;
 610   u32 ed_out2in_slowpath_node_index;
 611
 612   u32 hairpinning_node_index;
 613   u32 hairpin_dst_node_index;
 614   u32 hairpin_src_node_index;
 615   u32 ed_hairpinning_node_index;
 616   u32 ed_hairpin_dst_node_index;
 617   u32 ed_hairpin_src_node_index;
 618
 619   /* If forwarding is enabled */
 620   u8 forwarding_enabled;
 621
 622   /* Config parameters */
 623   u8 endpoint_dependent;
 624
 625   u8 out2in_dpo;
 626   /* static mapping config */
 627   u8 static_mapping_only;
 628   u8 static_mapping_connection_tracking;
 629
 630   /* Is translation memory size calculated or user defined */
 631   u8 translation_memory_size_set;
 632
 633   u32 translation_buckets;
 634   uword translation_memory_size;
 635   u32 max_translations_per_thread;
 636   u32 *max_translations_per_fib;
 637   u32 max_users_per_thread;
 638   u32 user_buckets;
 639   uword user_memory_size;
 640   u32 max_translations_per_user;
 641
 642   u32 outside_vrf_id;
 643   u32 outside_fib_index;
 644   u32 inside_vrf_id;
 645   u32 inside_fib_index;
 646
 647   /* values of various timeouts */
 648   u32 udp_timeout;
 649   u32 tcp_transitory_timeout;
 650   u32 tcp_established_timeout;
 651   u32 icmp_timeout;
 652
 653   /* TCP MSS clamping */
 654   u16 mss_clamping;
 655
 656   /* counters */
 657   vlib_simple_counter_main_t total_users;
 658   vlib_simple_counter_main_t total_sessions;
 659   vlib_simple_counter_main_t user_limit_reached;
 660
 661 #define _(x) vlib_simple_counter_main_t x;
 662   struct
 663   {
 664     struct
 665     {
 666       struct
 667       {
 668         foreach_nat_counter;
 669       } in2out;
 670
 671       struct
 672       {
 673         foreach_nat_counter;
 674       } out2in;
 675
 676       struct
 677       {
 678         foreach_nat_counter;
 679       } in2out_ed;
 680
 681       struct
 682       {
 683         foreach_nat_counter;
 684       } out2in_ed;
 685     } fastpath;
 686
 687     struct
 688     {
 689       struct
 690       {
 691         foreach_nat_counter;
 692       } in2out;
 693
 694       struct
 695       {
 696         foreach_nat_counter;
 697       } out2in;
 698
 699       struct
 700       {
 701         foreach_nat_counter;
 702       } in2out_ed;
 703
 704       struct
 705       {
 706         foreach_nat_counter;
 707       } out2in_ed;
 708     } slowpath;
 709
 710     vlib_simple_counter_main_t hairpinning;
 711   } counters;
 712 #undef _
 713
 714   /* API message ID base */
 715   u16 msg_id_base;
 716
 717   /* log class */
 718   vlib_log_class_t log_class;
 719   /* logging level */
 720   u8 log_level;
 721
 722   /* convenience */
 723   api_main_t *api_main;
 724   ip4_main_t *ip4_main;
 725   ip_lookup_main_t *ip4_lookup_main;
 726
 727   /* nat44 plugin enabled */
 728   u8 enabled;
 729
 730   vnet_main_t *vnet_main;
 731 } snat_main_t;
 732
 733 typedef struct
 734 {
 735   u32 thread_index;
 736   f64 now;
 737 } nat44_is_idle_session_ctx_t;
 738
 739 typedef struct
 740 {
 741   u32 cached_sw_if_index;
 742   u32 cached_ip4_address;
 743 } snat_runtime_t;
 744
 745 extern snat_main_t snat_main;
 746
 747 // nat pre ed next_node feature classification
 748 extern vlib_node_registration_t nat_default_node;
 749 extern vlib_node_registration_t nat_pre_in2out_node;
 750 extern vlib_node_registration_t nat_pre_out2in_node;
 751
 752 extern vlib_node_registration_t snat_in2out_node;
 753 extern vlib_node_registration_t snat_in2out_output_node;
 754 extern vlib_node_registration_t snat_out2in_node;
 755 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
 756 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
 757 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
 758 extern vlib_node_registration_t nat44_ed_in2out_node;
 759 extern vlib_node_registration_t nat44_ed_in2out_output_node;
 760 extern vlib_node_registration_t nat44_ed_out2in_node;
 761
 762 extern fib_source_t nat_fib_src_hi;
 763 extern fib_source_t nat_fib_src_low;
 764
 765 /* format functions */
 766 format_function_t format_snat_user;
 767 format_function_t format_snat_static_mapping;
 768 format_function_t format_snat_static_map_to_resolve;
 769 format_function_t format_snat_session;
 770 format_function_t format_snat_key;
 771 format_function_t format_static_mapping_key;
 772 format_function_t format_nat_protocol;
 773 format_function_t format_nat_addr_and_port_alloc_alg;
 774 /* unformat functions */
 775 unformat_function_t unformat_nat_protocol;
 776
 777 /** \brief Check if SNAT session is created from static mapping.
 778     @param s SNAT session
 779     @return 1 if SNAT session is created from static mapping otherwise 0
 780 */
 781 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
 782
 783 /** \brief Check if SNAT session for unknown protocol.
 784     @param s SNAT session
 785     @return 1 if SNAT session for unknown protocol otherwise 0
 786 */
 787 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
 788
 789 /** \brief Check if NAT session is twice NAT.
 790     @param s NAT session
 791     @return 1 if NAT session is twice NAT
 792 */
 793 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
 794
 795 /** \brief Check if NAT session is load-balancing.
 796     @param s NAT session
 797     @return 1 if NAT session is load-balancing
 798 */
 799 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
 800
 801 /** \brief Check if NAT session is forwarding bypass.
 802     @param s NAT session
 803     @return 1 if NAT session is load-balancing
 804 */
 805 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
 806
 807 /** \brief Check if NAT session is endpoint dependent.
 808     @param s NAT session
 809     @return 1 if NAT session is endpoint dependent
 810 */
 811 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
 812
 813 /** \brief Check if NAT session has affinity record.
 814     @param s NAT session
 815     @return 1 if NAT session has affinity record
 816 */
 817 #define is_affinity_sessions(s) (s->flags & SNAT_SESSION_FLAG_AFFINITY)
 818
 819 /** \brief Check if exact pool address should be used.
 820     @param s SNAT session
 821     @return 1 if exact pool address or 0
 822 */
 823 #define is_exact_address_session(s) (s->flags & SNAT_SESSION_FLAG_EXACT_ADDRESS)
 824
 825 /** \brief Check if NAT interface is inside.
 826     @param i NAT interface
 827     @return 1 if inside interface
 828 */
 829 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
 830
 831 /** \brief Check if NAT interface is outside.
 832     @param i NAT interface
 833     @return 1 if outside interface
 834 */
 835 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
 836
 837 /** \brief Check if NAT44 endpoint-dependent TCP session is closed.
 838     @param s NAT session
 839     @return 1 if session is closed
 840 */
 841 #define nat44_is_ses_closed(s) s->state == 0xf
 842
 843 /** \brief Check if NAT static mapping is address only (1:1NAT).
 844     @param sm NAT static mapping
 845     @return 1 if 1:1NAT, 0 if 1:1NAPT
 846 */
 847 #define is_addr_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_ADDR_ONLY)
 848
 849 /** \brief Check if NAT static mapping match only out2in direction.
 850     @param sm NAT static mapping
 851     @return 1 if rule match only out2in direction
 852 */
 853 #define is_out2in_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY)
 854
 855 /** \brief Check if NAT static mapping is identity NAT.
 856     @param sm NAT static mapping
 857     @return 1 if identity NAT
 858 */
 859 #define is_identity_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT)
 860
 861 /** \brief Check if NAT static mapping is load-balancing.
 862     @param sm NAT static mapping
 863     @return 1 if load-balancing
 864 */
 865 #define is_lb_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_LB)
 866
 867 /** \brief Check if exact pool address should be used.
 868     @param s SNAT session
 869     @return 1 if exact pool address or 0
 870 */
 871 #define is_exact_address(s) (s->flags & NAT_STATIC_MAPPING_FLAG_EXACT_ADDRESS)
 872
 873 /** \brief Check if client initiating TCP connection (received SYN from client)
 874     @param t TCP header
 875     @return 1 if client initiating TCP connection
 876 */
 877 always_inline bool
 878 tcp_flags_is_init (u8 f)
 879 {
 880   return (f & TCP_FLAG_SYN) && !(f & TCP_FLAG_ACK);
 881 }
 882
 883 /* logging */
 884 #define nat_log_err(...) \
 885   vlib_log(VLIB_LOG_LEVEL_ERR, snat_main.log_class, __VA_ARGS__)
 886 #define nat_log_warn(...) \
 887   vlib_log(VLIB_LOG_LEVEL_WARNING, snat_main.log_class, __VA_ARGS__)
 888 #define nat_log_notice(...) \
 889   vlib_log(VLIB_LOG_LEVEL_NOTICE, snat_main.log_class, __VA_ARGS__)
 890 #define nat_log_info(...) \
 891   vlib_log(VLIB_LOG_LEVEL_INFO, snat_main.log_class, __VA_ARGS__)
 892 #define nat_log_debug(...)\
 893   vlib_log(VLIB_LOG_LEVEL_DEBUG, snat_main.log_class, __VA_ARGS__)
 894
 895 /* NAT API Logging Levels */
 896 #define foreach_nat_log_level \
 897   _(0x00, LOG_NONE)           \
 898   _(0x01, LOG_ERROR)          \
 899   _(0x02, LOG_WARNING)        \
 900   _(0x03, LOG_NOTICE)         \
 901   _(0x04, LOG_INFO)           \
 902   _(0x05, LOG_DEBUG)
 903
 904 typedef enum nat_log_level_t_
 905 {
 906 #define _(n,f) SNAT_##f = n,
 907   foreach_nat_log_level
 908 #undef _
 909 } nat_log_level_t;
 910
 911 #define nat_elog(_level, _str)                           \
 912 do                                                       \
 913   {                                                      \
 914     snat_main_t *sm = &snat_main;                        \
 915     if (PREDICT_FALSE (sm->log_level >= _level))         \
 916       {                                                  \
 917         ELOG_TYPE_DECLARE (e) =                          \
 918           {                                              \
 919             .format = "nat-msg " _str,                   \
 920             .format_args = "",                           \
 921           };                                             \
 922         ELOG_DATA (&vlib_global_main.elog_main, e);      \
 923       }                                                  \
 924   } while (0);
 925
 926 #define nat_elog_addr(_level, _str, _addr)               \
 927 do                                                       \
 928   {                                                      \
 929     if (PREDICT_FALSE (sm->log_level >= _level))         \
 930       {                                                  \
 931         ELOG_TYPE_DECLARE (e) =                          \
 932           {                                              \
 933             .format = "nat-msg " _str " %d.%d.%d.%d",    \
 934             .format_args = "i1i1i1i1",                   \
 935           };                                             \
 936         CLIB_PACKED(struct                               \
 937           {                                              \
 938             u8 oct1;                                     \
 939             u8 oct2;                                     \
 940             u8 oct3;                                     \
 941             u8 oct4;                                     \
 942           }) *ed;                                        \
 943         ed = ELOG_DATA (&vlib_global_main.elog_main, e); \
 944         ed->oct4 = _addr >> 24;                          \
 945         ed->oct3 = _addr >> 16;                          \
 946         ed->oct2 = _addr >> 8;                           \
 947         ed->oct1 = _addr;                                \
 948     }                                                    \
 949   } while (0);
 950
 951 #define nat_elog_debug_handoff(_str, _tid, _fib, _src, _dst)                \
 952 do                                                                          \
 953   {                                                                         \
 954   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                      \
 955     {                                                                       \
 956       ELOG_TYPE_DECLARE (e) =                                               \
 957         {                                                                   \
 958           .format = "nat-msg " _str " ip src: %d.%d.%d.%d dst: %d.%d.%d.%d" \
 959                                     " tid from: %d to: %d fib: %d",         \
 960         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                            \
 961       };                                                                    \
 962       CLIB_PACKED(struct                                                    \
 963         {                                                                   \
 964           u8 src_oct1;                                                      \
 965           u8 src_oct2;                                                      \
 966           u8 src_oct3;                                                      \
 967           u8 src_oct4;                                                      \
 968           u8 dst_oct1;                                                      \
 969           u8 dst_oct2;                                                      \
 970           u8 dst_oct3;                                                      \
 971           u8 dst_oct4;                                                      \
 972           u32 ftid;                                                         \
 973           u32 ttid;                                                         \
 974           u32 fib;                                                          \
 975         }) *ed;                                                             \
 976       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                      \
 977       ed->src_oct1 = _src >> 24;                                            \
 978       ed->src_oct2 = _src >> 16;                                            \
 979       ed->src_oct3 = _src >> 8;                                             \
 980       ed->src_oct4 = _src;                                                  \
 981       ed->dst_oct1 = _dst >> 24;                                            \
 982       ed->dst_oct2 = _dst >> 16;                                            \
 983       ed->dst_oct3 = _dst >> 8;                                             \
 984       ed->dst_oct4 = _dst;                                                  \
 985       ed->ftid = vlib_get_thread_index ();                                  \
 986       ed->ttid = _tid;                                                      \
 987       ed->fib = _fib;                                                       \
 988     }                                                                       \
 989   } while (0);
 990
 991 #define nat_elog_debug_handoff_v2(_str, _prt, _fib, _src, _dst)              \
 992 do                                                                           \
 993   {                                                                          \
 994   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                       \
 995     {                                                                        \
 996       ELOG_TYPE_DECLARE (e) =                                                \
 997         {                                                                    \
 998           .format = "nat-msg " _str " ip_src:%d.%d.%d.%d ip_dst:%d.%d.%d.%d" \
 999                                     " tid:%d prt:%d fib:%d",                 \
1000         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                             \
1001       };                                                                     \
1002       CLIB_PACKED(struct                                                     \
1003         {                                                                    \
1004           u8 src_oct1;                                                       \
1005           u8 src_oct2;                                                       \
1006           u8 src_oct3;                                                       \
1007           u8 src_oct4;                                                       \
1008           u8 dst_oct1;                                                       \
1009           u8 dst_oct2;                                                       \
1010           u8 dst_oct3;                                                       \
1011           u8 dst_oct4;                                                       \
1012           u32 tid;                                                           \
1013           u32 prt;                                                           \
1014           u32 fib;                                                           \
1015         }) *ed;                                                              \
1016       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                       \
1017       ed->src_oct1 = _src >> 24;                                             \
1018       ed->src_oct2 = _src >> 16;                                             \
1019       ed->src_oct3 = _src >> 8;                                              \
1020       ed->src_oct4 = _src;                                                   \
1021       ed->dst_oct1 = _dst >> 24;                                             \
1022       ed->dst_oct2 = _dst >> 16;                                             \
1023       ed->dst_oct3 = _dst >> 8;                                              \
1024       ed->dst_oct4 = _dst;                                                   \
1025       ed->tid = vlib_get_thread_index ();                                    \
1026       ed->prt = _prt;                                                        \
1027       ed->fib = _fib;                                                        \
1028     }                                                                        \
1029   } while (0);
1030
1031 #define nat_elog_X1(_level, _fmt, _arg, _val1)            \
1032 do                                                        \
1033   {                                                       \
1034     snat_main_t *sm = &snat_main;                         \
1035     if (PREDICT_FALSE (sm->log_level >= _level))          \
1036       {                                                   \
1037         ELOG_TYPE_DECLARE (e) =                           \
1038           {                                               \
1039             .format = "nat-msg " _fmt,                    \
1040             .format_args = _arg,                          \
1041           };                                              \
1042         CLIB_PACKED(struct                                \
1043           {                                               \
1044             typeof (_val1) val1;                          \
1045           }) *ed;                                         \
1046         ed = ELOG_DATA (&vlib_global_main.elog_main, e);  \
1047         ed->val1 = _val1;                                 \
1048       }                                                   \
1049   } while (0);
1050
1051 #define nat_elog_notice(nat_elog_str) \
1052   nat_elog(SNAT_LOG_INFO, "[notice] " nat_elog_str)
1053 #define nat_elog_warn(nat_elog_str) \
1054   nat_elog(SNAT_LOG_WARNING, "[warning] " nat_elog_str)
1055 #define nat_elog_err(nat_elog_str) \
1056   nat_elog(SNAT_LOG_ERROR, "[error] " nat_elog_str)
1057 #define nat_elog_debug(nat_elog_str) \
1058   nat_elog(SNAT_LOG_DEBUG, "[debug] " nat_elog_str)
1059 #define nat_elog_info(nat_elog_str) \
1060   nat_elog(SNAT_LOG_INFO, "[info] " nat_elog_str)
1061
1062 #define nat_elog_notice_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1063   nat_elog_X1(SNAT_LOG_NOTICE, "[notice] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1064 #define nat_elog_warn_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1065   nat_elog_X1(SNAT_LOG_WARNING, "[warning] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1066 #define nat_elog_err_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1067   nat_elog_X1(SNAT_LOG_ERROR, "[error] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1068 #define nat_elog_debug_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1069   nat_elog_X1(SNAT_LOG_DEBUG, "[debug] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1070 #define nat_elog_info_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1071   nat_elog_X1(SNAT_LOG_INFO, "[info] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1072
1073 /* ICMP session match functions */
1074 u32 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1075                             u32 thread_index, vlib_buffer_t * b0,
1076                             ip4_header_t * ip0, ip4_address_t * addr,
1077                             u16 * port, u32 * fib_index,
1078                             nat_protocol_t * proto, void *d, void *e,
1079                             u8 * dont_translate);
1080 u32 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1081                             u32 thread_index, vlib_buffer_t * b0,
1082                             ip4_header_t * ip0, ip4_address_t * addr,
1083                             u16 * port, u32 * fib_index,
1084                             nat_protocol_t * proto, void *d, void *e,
1085                             u8 * dont_translate);
1086 u32 icmp_match_out2in_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1087                             u32 thread_index, vlib_buffer_t * b0,
1088                             ip4_header_t * ip0, ip4_address_t * addr,
1089                             u16 * port, u32 * fib_index,
1090                             nat_protocol_t * proto, void *d, void *e,
1091                             u8 * dont_translate);
1092 u32 icmp_match_out2in_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1093                             u32 thread_index, vlib_buffer_t * b0,
1094                             ip4_header_t * ip0, ip4_address_t * addr,
1095                             u16 * port, u32 * fib_index,
1096                             nat_protocol_t * proto, void *d, void *e,
1097                             u8 * dont_translate);
1098
1099 /* ICMP endpoint-dependent session match functions */
1100 u32 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1101                           u32 thread_index, vlib_buffer_t * b0,
1102                           ip4_header_t * ip0, ip4_address_t * addr,
1103                           u16 * port, u32 * fib_index, nat_protocol_t * proto,
1104                           void *d, void *e, u8 * dont_translate);
1105 u32 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1106                           u32 thread_index, vlib_buffer_t * b0,
1107                           ip4_header_t * ip0, ip4_address_t * addr,
1108                           u16 * port, u32 * fib_index, nat_protocol_t * proto,
1109                           void *d, void *e, u8 * dont_translate);
1110
1111 u32 icmp_in2out (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1112                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1113                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1114                  void *d, void *e);
1115
1116 u32 icmp_out2in (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1117                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1118                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1119                  void *d, void *e);
1120
1121 /* hairpinning functions */
1122 u32 snat_icmp_hairpinning (snat_main_t * sm, vlib_buffer_t * b0,
1123                            ip4_header_t * ip0, icmp46_header_t * icmp0,
1124                            int is_ed);
1125 void nat_hairpinning_sm_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1126                                        ip4_header_t * ip);
1127 void nat44_ed_hairpinning_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1128                                          ip4_header_t * ip);
1129 int snat_hairpinning (vlib_main_t * vm, vlib_node_runtime_t * node,
1130                       snat_main_t * sm, vlib_buffer_t * b0,
1131                       ip4_header_t * ip0, udp_header_t * udp0,
1132                       tcp_header_t * tcp0, u32 proto0, int is_ed,
1133                       int do_trace);
1134
1135 /* Call back functions for clib_bihash_add_or_overwrite_stale */
1136 int nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1137 int nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1138 int nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1139 int nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1140
1141
1142 /**
1143  * @brief Enable NAT44 plugin
1144  *
1145  * @param c         nat44_config_t
1146  *
1147  * @return 0 on success, non-zero value otherwise
1148  */
1149 int nat44_plugin_enable (nat44_config_t c);
1150
1151 /**
1152  * @brief Disable NAT44 plugin
1153  *
1154  * @return 0 on success, non-zero value otherwise
1155  */
1156 int nat44_plugin_disable ();
1157
1158 /**
1159  * @brief Add external address to NAT44 pool
1160  *
1161  * @param sm        snat global configuration data
1162  * @param addr      IPv4 address
1163  * @param vrf_id    VRF id of tenant, ~0 means independent of VRF
1164  * @param twice_nat 1 if twice NAT address
1165  *
1166  * @return 0 on success, non-zero value otherwise
1167  */
1168 int snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
1169                       u8 twice_nat);
1170
1171 /**
1172  * @brief Delete external address from NAT44 pool
1173  *
1174  * @param sm        snat global configuration data
1175  * @param addr      IPv4 address
1176  * @param delete_sm 1 if delete static mapping using address
1177  * @param twice_nat 1 if twice NAT address
1178  *
1179  * @return 0 on success, non-zero value otherwise
1180  */
1181 int snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
1182                       u8 twice_nat);
1183
1184 /**
1185  * @brief Add/delete external address to FIB DPO (out2in DPO mode)
1186  *
1187  * @param addr   IPv4 address
1188  * @param is_add 1 = add, 0 = delete
1189  *
1190  * @return 0 on success, non-zero value otherwise
1191  */
1192 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
1193
1194 /**
1195  * @brief Add/delete NAT44 static mapping
1196  *
1197  * @param l_addr       local IPv4 address
1198  * @param e_addr       external IPv4 address
1199  * @param l_port       local port number
1200  * @param e_port       external port number
1201  * @param vrf_id       local VRF ID
1202  * @param addr_only    1 = 1:1NAT, 0 = 1:1NAPT
1203  * @param sw_if_index  use interface address as external IPv4 address
1204  * @param proto        L4 protocol
1205  * @param is_add       1 = add, 0 = delete
1206  * @param twice_nat    twice-nat mode
1207  * @param out2in_only  if 1 rule match only out2in direction
1208  * @param tag          opaque string tag
1209  * @param identity_nat identity NAT
1210  * @param pool_addr    pool IPv4 address
1211  * @param exact        1 = exact pool address
1212  *
1213  * @return 0 on success, non-zero value otherwise
1214  */
1215 int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
1216                              u16 l_port, u16 e_port, u32 vrf_id,
1217                              int addr_only, u32 sw_if_index,
1218                              nat_protocol_t proto, int is_add,
1219                              twice_nat_type_t twice_nat, u8 out2in_only,
1220                              u8 * tag, u8 identity_nat,
1221                              ip4_address_t pool_addr, int exact);
1222
1223 /**
1224  * @brief Add/delete static mapping with load-balancing (multiple backends)
1225  *
1226  * @param e_addr      external IPv4 address
1227  * @param e_port      external port number
1228  * @param proto       L4 protocol
1229  * @param locals      list of local backends
1230  * @param is_add      1 = add, 0 = delete
1231  * @param twice_nat   twice-nat mode
1232  * @param out2in_only if 1 rule match only out2in direction
1233  * @param tag         opaque string tag
1234  * @param affinity    0 = disabled, otherwise client IP affinity sticky time
1235  *
1236  * @return 0 on success, non-zero value otherwise
1237  */
1238 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
1239                                      nat_protocol_t proto,
1240                                      nat44_lb_addr_port_t * locals, u8 is_add,
1241                                      twice_nat_type_t twice_nat,
1242                                      u8 out2in_only, u8 * tag, u32 affinity);
1243
1244 int nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
1245                                            ip4_address_t l_addr, u16 l_port,
1246                                            nat_protocol_t proto, u32 vrf_id,
1247                                            u8 probability, u8 is_add);
1248
1249 clib_error_t *snat_api_init (vlib_main_t * vm, snat_main_t * sm);
1250
1251 /**
1252  * @brief Set NAT plugin workers
1253  *
1254  * @param bitmap NAT workers bitmap
1255  *
1256  * @return 0 on success, non-zero value otherwise
1257  */
1258 int snat_set_workers (uword * bitmap);
1259
1260 /**
1261  * @brief Enable/disable NAT44 feature on the interface
1262  *
1263  * @param sw_if_index software index of the interface
1264  * @param is_inside   1 = inside, 0 = outside
1265  * @param is_del      1 = delete, 0 = add
1266  *
1267  * @return 0 on success, non-zero value otherwise
1268  */
1269 int snat_interface_add_del (u32 sw_if_index, u8 is_inside, int is_del);
1270
1271 /**
1272  * @brief Enable/disable NAT44 output feature on the interface (postrouting NAT)
1273  *
1274  * @param sw_if_index software index of the interface
1275  * @param is_inside   1 = inside, 0 = outside
1276  * @param is_del      1 = delete, 0 = add
1277  *
1278  * @return 0 on success, non-zero value otherwise
1279  */
1280 int snat_interface_add_del_output_feature (u32 sw_if_index, u8 is_inside,
1281                                            int is_del);
1282
1283 /**
1284  * @brief Add/delete NAT44 pool address from specific interface
1285  *
1286  * @param sw_if_index software index of the interface
1287  * @param is_del      1 = delete, 0 = add
1288  * @param twice_nat   1 = twice NAT address for external hosts
1289  *
1290  * @return 0 on success, non-zero value otherwise
1291  */
1292 int snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
1293                                 u8 twice_nat);
1294
1295 /**
1296  * @brief Delete NAT44 session
1297  *
1298  * @param addr   IPv4 address
1299  * @param port   L4 port number
1300  * @param proto  L4 protocol
1301  * @param vrf_id VRF ID
1302  * @param is_in  1 = inside network address and port pair, 0 = outside
1303  *
1304  * @return 0 on success, non-zero value otherwise
1305  */
1306 int nat44_del_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1307                        nat_protocol_t proto, u32 vrf_id, int is_in);
1308
1309 /**
1310  * @brief Delete NAT44 endpoint-dependent session
1311  *
1312  * @param sm     snat global configuration data
1313  * @param addr   IPv4 address
1314  * @param port   L4 port number
1315  * @param proto  L4 protocol
1316  * @param vrf_id VRF ID
1317  * @param is_in  1 = inside network address and port pair, 0 = outside
1318  *
1319  * @return 0 on success, non-zero value otherwise
1320  */
1321 int nat44_del_ed_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1322                           ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1323                           u32 vrf_id, int is_in);
1324
1325 /**
1326  * @brief Free NAT44 session data (lookup keys, external address port)
1327  *
1328  * @param sm           snat global configuration data
1329  * @param s            NAT session
1330  * @param thread_index thread index
1331  * @param is_ha        is HA event
1332  */
1333 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
1334                             u32 thread_index, u8 is_ha);
1335
1336 /**
1337  * @brief Set NAT44 session limit (session limit, vrf id)
1338  *
1339  * @param session_limit Session limit
1340  * @param vrf_id        VRF id
1341  * @return 0 on success, non-zero value otherwise
1342  */
1343 int nat44_set_session_limit (u32 session_limit, u32 vrf_id);
1344
1345 /**
1346  * @brief Update NAT44 session limit flushing all data (session limit, vrf id)
1347  *
1348  * @param session_limit Session limit
1349  * @param vrf_id        VRF id
1350  * @return 0 on success, non-zero value otherwise
1351  */
1352 int nat44_update_session_limit (u32 session_limit, u32 vrf_id);
1353 /**
1354  * @brief Free NAT44 ED session data (lookup keys, external address port)
1355  *
1356  * @param s            NAT session
1357  * @param thread_index thread index
1358  * @param is_ha        is HA event
1359  */
1360 void
1361 nat44_free_session_data (snat_main_t * sm, snat_session_t * s,
1362                          u32 thread_index, u8 is_ha);
1363
1364 /**
1365  * @brief Initialize NAT44 data
1366  *
1367  * @param tsm          per thread data
1368  */
1369 void nat44_db_init (snat_main_per_thread_data_t * tsm);
1370
1371 /**
1372  * @brief Free NAT44 data
1373  *
1374  * @param tsm          per thread data
1375  */
1376 void nat44_db_free (snat_main_per_thread_data_t * tsm);
1377
1378 void nat44_sessions_clear ();
1379
1380 /**
1381  * @brief Find or create NAT user
1382  *
1383  * @param sm           snat global configuration data
1384  * @param addr         IPv4 address
1385  * @param fib_index    FIB table index
1386  * @param thread_index thread index
1387  *
1388  * @return NAT user data structure on success otherwise zero value
1389  */
1390 snat_user_t *nat_user_get_or_create (snat_main_t * sm,
1391                                      ip4_address_t * addr, u32 fib_index,
1392                                      u32 thread_index);
1393
1394 /**
1395  * @brief Allocate new NAT session or recycle last used
1396  *
1397  * @param sm           snat global configuration data
1398  * @param u            NAT user
1399  * @param thread_index thread index
1400  * @param now          time now
1401  *
1402  * @return session data structure on success otherwise zero value
1403  */
1404 snat_session_t *nat_session_alloc_or_recycle (snat_main_t * sm,
1405                                               snat_user_t * u,
1406                                               u32 thread_index, f64 now);
1407
1408 /**
1409  * @brief Set address and port assignment algorithm for MAP-E CE
1410  *
1411  * @param psid        Port Set Identifier value
1412  * @param psid_offset number of offset bits
1413  * @param psid_length length of PSID
1414  */
1415 void nat_set_alloc_addr_and_port_mape (u16 psid, u16 psid_offset,
1416                                        u16 psid_length);
1417
1418 /**
1419  * @brief Set address and port assignment algorithm for port range
1420  *
1421  * @param start_port beginning of the port range
1422  * @param end_port   end of the port range
1423  */
1424 void nat_set_alloc_addr_and_port_range (u16 start_port, u16 end_port);
1425
1426 /**
1427  * @brief Set address and port assignment algorithm to default/standard
1428  */
1429 void nat_set_alloc_addr_and_port_default (void);
1430
1431 /**
1432  * @brief Free outside address and port pair
1433  *
1434  * @param addresses    vector of outside addresses
1435  * @param thread_index thread index
1436  * @param key          address, port and protocol
1437  */
1438 void
1439 snat_free_outside_address_and_port (snat_address_t * addresses,
1440                                     u32 thread_index,
1441                                     ip4_address_t * addr,
1442                                     u16 port, nat_protocol_t protocol);
1443
1444 /**
1445  * @brief Alloc outside address and port
1446  *
1447  * @param addresses         vector of outside addresses
1448  * @param fib_index         FIB table index
1449  * @param thread_index      thread index
1450  * @param port_per_thread   number of ports per thread
1451  * @param snat_thread_index NAT thread index
1452  *
1453  * @return 0 on success, non-zero value otherwise
1454  */
1455 int snat_alloc_outside_address_and_port (snat_address_t * addresses,
1456                                          u32 fib_index,
1457                                          u32 thread_index,
1458                                          nat_protocol_t proto,
1459                                          ip4_address_t * addr,
1460                                          u16 * port,
1461                                          u16 port_per_thread,
1462                                          u32 snat_thread_index);
1463
1464 void expire_per_vrf_sessions (u32 fib_index);
1465
1466 /**
1467  * @brief Match NAT44 static mapping.
1468  *
1469  * @param key             address and port to match
1470  * @param addr            external/local address of the matched mapping
1471  * @param port            port of the matched mapping
1472  * @param fib_index       fib index of the matched mapping
1473  * @param by_external     if 0 match by local address otherwise match by external
1474  *                        address
1475  * @param is_addr_only    1 if matched mapping is address only
1476  * @param twice_nat       matched mapping is twice NAT type
1477  * @param lb              1 if matched mapping is load-balanced
1478  * @param ext_host_addr   external host address
1479  * @param is_identity_nat 1 if indentity mapping
1480  * @param out             if !=0 set to pointer of the mapping structure
1481  *
1482  * @returns 0 if match found otherwise 1.
1483  */
1484 int snat_static_mapping_match (snat_main_t * sm,
1485                                ip4_address_t match_addr,
1486                                u16 match_port,
1487                                u32 match_fib_index,
1488                                nat_protocol_t match_protocol,
1489                                ip4_address_t * mapping_addr,
1490                                u16 * mapping_port,
1491                                u32 * mapping_fib_index,
1492                                u8 by_external,
1493                                u8 * is_addr_only,
1494                                twice_nat_type_t * twice_nat,
1495                                lb_nat_type_t * lb,
1496                                ip4_address_t * ext_host_addr,
1497                                u8 * is_identity_nat,
1498                                snat_static_mapping_t ** out);
1499
1500 /**
1501  * @brief Add/del NAT address to FIB.
1502  *
1503  * Add the external NAT address to the FIB as receive entries. This ensures
1504  * that VPP will reply to ARP for this address and we don't need to enable
1505  * proxy ARP on the outside interface.
1506  *
1507  * @param addr        IPv4 address
1508  * @param plen        address prefix length
1509  * @param sw_if_index software index of the outside interface
1510  * @param is_add      0 = delete, 1 = add.
1511  */
1512 void snat_add_del_addr_to_fib (ip4_address_t * addr,
1513                                u8 p_len, u32 sw_if_index, int is_add);
1514
1515 /*
1516  * Why is this here? Because we don't need to touch this layer to
1517  * simply reply to an icmp. We need to change id to a unique
1518  * value to NAT an echo request/reply.
1519  */
1520
1521 typedef struct
1522 {
1523   u16 identifier;
1524   u16 sequence;
1525 } icmp_echo_header_t;
1526
1527 typedef struct
1528 {
1529   u16 src_port, dst_port;
1530 } tcp_udp_header_t;
1531
1532 u8 *format_user_kvp (u8 * s, va_list * args);
1533
1534 #endif /* __included_nat_h__ */
1535 /*
1536  * fd.io coding-style-patch-verification: ON
1537  *
1538  * Local Variables:
1539  * eval: (c-set-style "gnu")
1540  * End:
1541  */