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 typedef enum
  52 {
  53   NAT_NEXT_DROP,
  54   NAT_NEXT_ICMP_ERROR,
  55   NAT_NEXT_IN2OUT_ED_FAST_PATH,
  56   NAT_NEXT_IN2OUT_ED_SLOW_PATH,
  57   NAT_NEXT_IN2OUT_ED_OUTPUT_FAST_PATH,
  58   NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH,
  59   NAT_NEXT_OUT2IN_ED_FAST_PATH,
  60   NAT_NEXT_OUT2IN_ED_SLOW_PATH,
  61   NAT_NEXT_IN2OUT_CLASSIFY,
  62   NAT_NEXT_OUT2IN_CLASSIFY,
  63   NAT_N_NEXT,
  64 } nat_next_t;
  65
  66 typedef struct
  67 {
  68   u32 next_index;
  69   u32 arc_next_index;
  70 } nat_pre_trace_t;
  71
  72 /* user (internal host) key */
  73 typedef struct
  74 {
  75   union
  76   {
  77     struct
  78     {
  79       ip4_address_t addr;
  80       u32 fib_index;
  81     };
  82     u64 as_u64;
  83   };
  84 } snat_user_key_t;
  85
  86 /* NAT API Configuration flags */
  87 #define foreach_nat_config_flag \
  88   _(0x01, IS_TWICE_NAT)         \
  89   _(0x02, IS_SELF_TWICE_NAT)    \
  90   _(0x04, IS_OUT2IN_ONLY)       \
  91   _(0x08, IS_ADDR_ONLY)         \
  92   _(0x10, IS_OUTSIDE)           \
  93   _(0x20, IS_INSIDE)            \
  94   _(0x40, IS_STATIC)            \
  95   _(0x80, IS_EXT_HOST_VALID)    \
  96
  97 typedef enum nat_config_flags_t_
  98 {
  99 #define _(n,f) NAT_API_##f = n,
 100   foreach_nat_config_flag
 101 #undef _
 102 } nat_config_flags_t;
 103
 104 /* External address and port allocation modes */
 105 #define foreach_nat_addr_and_port_alloc_alg \
 106   _(0, DEFAULT, "default")         \
 107   _(1, MAPE, "map-e")              \
 108   _(2, RANGE, "port-range")
 109
 110 typedef enum
 111 {
 112 #define _(v, N, s) NAT_ADDR_AND_PORT_ALLOC_ALG_##N = v,
 113   foreach_nat_addr_and_port_alloc_alg
 114 #undef _
 115 } nat_addr_and_port_alloc_alg_t;
 116
 117 /* Session state */
 118 #define foreach_snat_session_state          \
 119   _(0, UNKNOWN, "unknown")                 \
 120   _(1, UDP_ACTIVE, "udp-active")           \
 121   _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
 122   _(3, TCP_ESTABLISHED, "tcp-established") \
 123   _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
 124   _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
 125   _(6, TCP_CLOSING, "tcp-closing")         \
 126   _(7, TCP_LAST_ACK, "tcp-last-ack")       \
 127   _(8, TCP_CLOSED, "tcp-closed")           \
 128   _(9, ICMP_ACTIVE, "icmp-active")
 129
 130 typedef enum
 131 {
 132 #define _(v, N, s) SNAT_SESSION_##N = v,
 133   foreach_snat_session_state
 134 #undef _
 135 } snat_session_state_t;
 136
 137 #define foreach_nat_in2out_ed_error                     \
 138 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 139 _(OUT_OF_PORTS, "out of ports")                         \
 140 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 141 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 142 _(NON_SYN, "non-SYN packet try to create session")      \
 143 _(TCP_CLOSED, "drops due to TCP in transitory timeout")
 144
 145 typedef enum
 146 {
 147 #define _(sym,str) NAT_IN2OUT_ED_ERROR_##sym,
 148   foreach_nat_in2out_ed_error
 149 #undef _
 150     NAT_IN2OUT_ED_N_ERROR,
 151 } nat_in2out_ed_error_t;
 152
 153 #define foreach_nat_out2in_ed_error                     \
 154 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 155 _(OUT_OF_PORTS, "out of ports")                         \
 156 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 157 _(NO_TRANSLATION, "no translation")                     \
 158 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 159 _(MAX_USER_SESS_EXCEEDED, "max user sessions exceeded") \
 160 _(CANNOT_CREATE_USER, "cannot create NAT user")         \
 161 _(NON_SYN, "non-SYN packet try to create session")      \
 162 _(TCP_CLOSED, "drops due to TCP in transitory timeout")
 163
 164 typedef enum
 165 {
 166 #define _(sym,str) NAT_OUT2IN_ED_ERROR_##sym,
 167   foreach_nat_out2in_ed_error
 168 #undef _
 169     NAT_OUT2IN_ED_N_ERROR,
 170 } nat_out2in_ed_error_t;
 171
 172
 173 /* Endpoint dependent TCP session state */
 174 #define NAT44_SES_I2O_FIN 1
 175 #define NAT44_SES_O2I_FIN 2
 176 #define NAT44_SES_I2O_FIN_ACK 4
 177 #define NAT44_SES_O2I_FIN_ACK 8
 178 #define NAT44_SES_I2O_SYN 16
 179 #define NAT44_SES_O2I_SYN 32
 180 #define NAT44_SES_RST     64
 181
 182 /* Session flags */
 183 #define SNAT_SESSION_FLAG_STATIC_MAPPING       1
 184 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO        2
 185 #define SNAT_SESSION_FLAG_LOAD_BALANCING       4
 186 #define SNAT_SESSION_FLAG_TWICE_NAT            8
 187 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT   16
 188 #define SNAT_SESSION_FLAG_FWD_BYPASS           32
 189 #define SNAT_SESSION_FLAG_AFFINITY             64
 190 #define SNAT_SESSION_FLAG_OUTPUT_FEATURE       128
 191 #define SNAT_SESSION_FLAG_EXACT_ADDRESS        256
 192
 193 /* NAT interface flags */
 194 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
 195 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
 196
 197 /* Static mapping flags */
 198 #define NAT_STATIC_MAPPING_FLAG_ADDR_ONLY      1
 199 #define NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY    2
 200 #define NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT   4
 201 #define NAT_STATIC_MAPPING_FLAG_LB             8
 202 #define NAT_STATIC_MAPPING_FLAG_EXACT_ADDRESS  16
 203
 204 /* *INDENT-OFF* */
 205 typedef CLIB_PACKED(struct
 206 {
 207   // number of sessions in this vrf
 208   u32 ses_count;
 209
 210   u32 rx_fib_index;
 211   u32 tx_fib_index;
 212
 213   // is this vrf expired
 214   u8 expired;
 215 }) per_vrf_sessions_t;
 216 /* *INDENT-ON* */
 217
 218 /* *INDENT-OFF* */
 219 typedef CLIB_PACKED(struct
 220 {
 221   /* Outside network tuple */
 222   struct
 223   {
 224     ip4_address_t addr;
 225     u32 fib_index;
 226     u16 port;
 227   } out2in;
 228
 229   /* Inside network tuple */
 230   struct
 231   {
 232     ip4_address_t addr;
 233     u32 fib_index;
 234     u16 port;
 235   } in2out;
 236
 237   nat_protocol_t nat_proto;
 238
 239   /* Flags */
 240   u32 flags;
 241
 242   /* Per-user translations */
 243   u32 per_user_index;
 244   u32 per_user_list_head_index;
 245
 246   /* head of LRU list in which this session is tracked */
 247   u32 lru_head_index;
 248   /* index in global LRU list */
 249   u32 lru_index;
 250   f64 last_lru_update;
 251
 252   /* Last heard timer */
 253   f64 last_heard;
 254
 255   /* Last HA refresh */
 256   f64 ha_last_refreshed;
 257
 258   /* Counters */
 259   u64 total_bytes;
 260   u32 total_pkts;
 261
 262   /* External host address and port */
 263   ip4_address_t ext_host_addr;
 264   u16 ext_host_port;
 265
 266   /* External host address and port after translation */
 267   ip4_address_t ext_host_nat_addr;
 268   u16 ext_host_nat_port;
 269
 270   /* TCP session state */
 271   u8 state;
 272   u32 i2o_fin_seq;
 273   u32 o2i_fin_seq;
 274   u64 tcp_closed_timestamp;
 275
 276   /* user index */
 277   u32 user_index;
 278
 279   /* per vrf sessions index */
 280   u32 per_vrf_sessions_index;
 281
 282 }) snat_session_t;
 283 /* *INDENT-ON* */
 284
 285 typedef struct
 286 {
 287   ip4_address_t addr;
 288   u32 fib_index;
 289   u32 sessions_per_user_list_head_index;
 290   u32 nsessions;
 291   u32 nstaticsessions;
 292 } snat_user_t;
 293
 294 typedef struct
 295 {
 296   ip4_address_t addr;
 297   u32 fib_index;
 298 /* *INDENT-OFF* */
 299 #define _(N, i, n, s) \
 300   u16 busy_##n##_ports; \
 301   u16 * busy_##n##_ports_per_thread; \
 302   u32 busy_##n##_port_refcounts[65535];
 303   foreach_nat_protocol
 304 #undef _
 305 /* *INDENT-ON* */
 306 } snat_address_t;
 307
 308 typedef struct
 309 {
 310   u32 fib_index;
 311   u32 ref_count;
 312 } nat_fib_t;
 313
 314 typedef struct
 315 {
 316   u32 fib_index;
 317   u32 refcount;
 318 } nat_outside_fib_t;
 319
 320 typedef struct
 321 {
 322   /* backend IP address */
 323   ip4_address_t addr;
 324   /* backend port number */
 325   u16 port;
 326   /* probability of the backend to be randomly matched */
 327   u8 probability;
 328   u8 prefix;
 329   /* backend FIB table */
 330   u32 vrf_id;
 331   u32 fib_index;
 332 } nat44_lb_addr_port_t;
 333
 334 typedef enum
 335 {
 336   /* twice-nat disabled */
 337   TWICE_NAT_DISABLED,
 338   /* twice-nat enabled */
 339   TWICE_NAT,
 340   /* twice-nat only when src IP equals dst IP after translation */
 341   TWICE_NAT_SELF,
 342 } twice_nat_type_t;
 343
 344 typedef enum
 345 {
 346   /* no load-balancing */
 347   NO_LB_NAT,
 348   /* load-balancing */
 349   LB_NAT,
 350   /* load-balancing with affinity */
 351   AFFINITY_LB_NAT,
 352 } lb_nat_type_t;
 353
 354 typedef struct
 355 {
 356   /* prefered pool address */
 357   ip4_address_t pool_addr;
 358   /* local IP address */
 359   ip4_address_t local_addr;
 360   /* external IP address */
 361   ip4_address_t external_addr;
 362   /* local port */
 363   u16 local_port;
 364   /* external port */
 365   u16 external_port;
 366   /* is twice-nat */
 367   twice_nat_type_t twice_nat;
 368   /* local FIB table */
 369   u32 vrf_id;
 370   u32 fib_index;
 371   /* protocol */
 372   nat_protocol_t proto;
 373   /* 0 = disabled, otherwise client IP affinity sticky time in seconds */
 374   u32 affinity;
 375   /* worker threads used by backends/local host */
 376   u32 *workers;
 377   /* opaque string tag */
 378   u8 *tag;
 379   /* backends for load-balancing mode */
 380   nat44_lb_addr_port_t *locals;
 381   /* affinity per service lis */
 382   u32 affinity_per_service_list_head_index;
 383   /* flags */
 384   u32 flags;
 385 } snat_static_mapping_t;
 386
 387 typedef struct
 388 {
 389   u32 sw_if_index;
 390   u8 flags;
 391 } snat_interface_t;
 392
 393 typedef struct
 394 {
 395   ip4_address_t l_addr;
 396   ip4_address_t pool_addr;
 397   u16 l_port;
 398   u16 e_port;
 399   u32 sw_if_index;
 400   u32 vrf_id;
 401   nat_protocol_t proto;
 402   u32 flags;
 403   int addr_only;
 404   int twice_nat;
 405   int is_add;
 406   int out2in_only;
 407   int identity_nat;
 408   int exact;
 409   u8 *tag;
 410 } snat_static_map_resolve_t;
 411
 412 typedef struct
 413 {
 414   /* Main lookup tables */
 415   clib_bihash_8_8_t out2in;
 416   clib_bihash_8_8_t in2out;
 417
 418   /* Endpoint dependent sessions lookup tables */
 419   clib_bihash_16_8_t in2out_ed;
 420
 421   /* Find-a-user => src address lookup */
 422   clib_bihash_8_8_t user_hash;
 423
 424   /* User pool */
 425   snat_user_t *users;
 426
 427   /* Session pool */
 428   snat_session_t *sessions;
 429
 430   /* Pool of doubly-linked list elements */
 431   dlist_elt_t *list_pool;
 432
 433   /* LRU session list - head is stale, tail is fresh */
 434   dlist_elt_t *lru_pool;
 435   u32 tcp_trans_lru_head_index;
 436   u32 tcp_estab_lru_head_index;
 437   u32 udp_lru_head_index;
 438   u32 icmp_lru_head_index;
 439   u32 unk_proto_lru_head_index;
 440
 441   /* NAT thread index */
 442   u32 snat_thread_index;
 443
 444   /* real thread index */
 445   u32 thread_index;
 446
 447   per_vrf_sessions_t *per_vrf_sessions_vec;
 448
 449 } snat_main_per_thread_data_t;
 450
 451 struct snat_main_s;
 452
 453 /* ICMP session match function */
 454 typedef u32 (snat_icmp_match_function_t) (struct snat_main_s * sm,
 455                                           vlib_node_runtime_t * node,
 456                                           u32 thread_index,
 457                                           vlib_buffer_t * b0,
 458                                           ip4_header_t * ip0,
 459                                           ip4_address_t * addr,
 460                                           u16 * port,
 461                                           u32 * fib_index,
 462                                           nat_protocol_t * proto,
 463                                           void *d, void *e,
 464                                           u8 * dont_translate);
 465
 466 /* Return worker thread index for given packet */
 467 typedef u32 (snat_get_worker_in2out_function_t) (ip4_header_t * ip,
 468                                                  u32 rx_fib_index,
 469                                                  u8 is_output);
 470
 471 typedef u32 (snat_get_worker_out2in_function_t) (vlib_buffer_t * b,
 472                                                  ip4_header_t * ip,
 473                                                  u32 rx_fib_index,
 474                                                  u8 is_output);
 475
 476 /* NAT address and port allocation function */
 477 typedef int (nat_alloc_out_addr_and_port_function_t) (snat_address_t *
 478                                                       addresses,
 479                                                       u32 fib_index,
 480                                                       u32 thread_index,
 481                                                       nat_protocol_t proto,
 482                                                       ip4_address_t * addr,
 483                                                       u16 * port,
 484                                                       u16 port_per_thread,
 485                                                       u32 snat_thread_index);
 486
 487 #define foreach_nat_counter _ (tcp) _ (udp) _ (icmp) _ (other) _ (drops)
 488
 489 typedef struct snat_main_s
 490 {
 491   /* ICMP session match functions */
 492   snat_icmp_match_function_t *icmp_match_in2out_cb;
 493   snat_icmp_match_function_t *icmp_match_out2in_cb;
 494
 495   /* Thread settings */
 496   u32 num_workers;
 497   u32 first_worker_index;
 498   u32 *workers;
 499   snat_get_worker_in2out_function_t *worker_in2out_cb;
 500   snat_get_worker_out2in_function_t *worker_out2in_cb;
 501   u16 port_per_thread;
 502
 503   /* Per thread data */
 504   snat_main_per_thread_data_t *per_thread_data;
 505
 506   /* Find a static mapping by local */
 507   clib_bihash_8_8_t static_mapping_by_local;
 508
 509   /* Find a static mapping by external */
 510   clib_bihash_8_8_t static_mapping_by_external;
 511
 512   /* Static mapping pool */
 513   snat_static_mapping_t *static_mappings;
 514
 515   /* Endpoint-dependent out2in mappings */
 516   clib_bihash_16_8_t out2in_ed;
 517
 518   /* Interface pool */
 519   snat_interface_t *interfaces;
 520   snat_interface_t *output_feature_interfaces;
 521
 522   /* Vector of outside addresses */
 523   snat_address_t *addresses;
 524   /* Address and port allocation function */
 525   nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
 526   /* Address and port allocation type */
 527   nat_addr_and_port_alloc_alg_t addr_and_port_alloc_alg;
 528   /* Port set parameters (MAP-E) */
 529   u8 psid_offset;
 530   u8 psid_length;
 531   u16 psid;
 532   /* Port range parameters */
 533   u16 start_port;
 534   u16 end_port;
 535
 536   /* vector of fibs */
 537   nat_fib_t *fibs;
 538
 539   /* vector of outside fibs */
 540   nat_outside_fib_t *outside_fibs;
 541
 542   /* Vector of twice NAT addresses for external hosts */
 543   snat_address_t *twice_nat_addresses;
 544
 545   /* sw_if_indices whose intfc addresses should be auto-added */
 546   u32 *auto_add_sw_if_indices;
 547   u32 *auto_add_sw_if_indices_twice_nat;
 548
 549   /* vector of interface address static mappings to resolve. */
 550   snat_static_map_resolve_t *to_resolve;
 551
 552   /* Randomize port allocation order */
 553   u32 random_seed;
 554
 555   /* Worker handoff frame-queue index */
 556   u32 fq_in2out_index;
 557   u32 fq_in2out_output_index;
 558   u32 fq_out2in_index;
 559
 560   /* node indexes */
 561   u32 error_node_index;
 562
 563   /* handoff fq nodes  */
 564   u32 handoff_out2in_index;
 565   u32 handoff_in2out_index;
 566   u32 handoff_in2out_output_index;
 567
 568   /* respect feature arc nodes */
 569   u32 pre_out2in_node_index;
 570   u32 pre_in2out_node_index;
 571
 572   u32 in2out_node_index;
 573   u32 in2out_output_node_index;
 574   u32 in2out_fast_node_index;
 575   u32 in2out_slowpath_node_index;
 576   u32 in2out_slowpath_output_node_index;
 577   u32 ed_in2out_node_index;
 578   u32 ed_in2out_slowpath_node_index;
 579   u32 out2in_node_index;
 580   u32 out2in_fast_node_index;
 581   u32 ed_out2in_node_index;
 582   u32 ed_out2in_slowpath_node_index;
 583
 584   u32 hairpinning_node_index;
 585   u32 hairpin_dst_node_index;
 586   u32 hairpin_src_node_index;
 587   u32 ed_hairpinning_node_index;
 588   u32 ed_hairpin_dst_node_index;
 589   u32 ed_hairpin_src_node_index;
 590
 591   /* If forwarding is enabled */
 592   u8 forwarding_enabled;
 593
 594   /* Config parameters */
 595   u8 static_mapping_only;
 596   u8 static_mapping_connection_tracking;
 597   u8 out2in_dpo;
 598   u8 endpoint_dependent;
 599
 600   /* Is translation memory size calculated or user defined */
 601   u8 translation_memory_size_set;
 602
 603   u32 translation_buckets;
 604   uword translation_memory_size;
 605   u32 max_translations_per_thread;
 606   u32 *max_translations_per_fib;
 607   u32 max_users_per_thread;
 608   u32 user_buckets;
 609   uword user_memory_size;
 610   u32 max_translations_per_user;
 611
 612   u32 outside_vrf_id;
 613   u32 outside_fib_index;
 614   u32 inside_vrf_id;
 615   u32 inside_fib_index;
 616
 617   /* values of various timeouts */
 618   // proto timeouts
 619   u32 udp_timeout;
 620   u32 tcp_transitory_timeout;
 621   u32 tcp_established_timeout;
 622   u32 icmp_timeout;
 623
 624   /* TCP MSS clamping */
 625   u16 mss_clamping;
 626
 627   /* counters/gauges */
 628   vlib_simple_counter_main_t total_users;
 629   vlib_simple_counter_main_t total_sessions;
 630   vlib_simple_counter_main_t user_limit_reached;
 631
 632 #define _(x) vlib_simple_counter_main_t x;
 633   struct
 634   {
 635     struct
 636     {
 637       struct
 638       {
 639         foreach_nat_counter;
 640       } in2out;
 641
 642       struct
 643       {
 644         foreach_nat_counter;
 645       } out2in;
 646
 647       struct
 648       {
 649         foreach_nat_counter;
 650       } in2out_ed;
 651
 652       struct
 653       {
 654         foreach_nat_counter;
 655       } out2in_ed;
 656     } fastpath;
 657
 658     struct
 659     {
 660       struct
 661       {
 662         foreach_nat_counter;
 663       } in2out;
 664
 665       struct
 666       {
 667         foreach_nat_counter;
 668       } out2in;
 669
 670       struct
 671       {
 672         foreach_nat_counter;
 673       } in2out_ed;
 674
 675       struct
 676       {
 677         foreach_nat_counter;
 678       } out2in_ed;
 679     } slowpath;
 680
 681     vlib_simple_counter_main_t hairpinning;
 682   } counters;
 683 #undef _
 684
 685   /* API message ID base */
 686   u16 msg_id_base;
 687
 688   /* log class */
 689   vlib_log_class_t log_class;
 690   /* logging level */
 691   u8 log_level;
 692
 693   /* convenience */
 694   vnet_main_t *vnet_main;
 695   ip4_main_t *ip4_main;
 696   ip_lookup_main_t *ip4_lookup_main;
 697   api_main_t *api_main;
 698 } snat_main_t;
 699
 700 typedef struct
 701 {
 702   u32 thread_index;
 703   f64 now;
 704 } nat44_is_idle_session_ctx_t;
 705
 706 typedef struct
 707 {
 708   u32 cached_sw_if_index;
 709   u32 cached_ip4_address;
 710 } snat_runtime_t;
 711
 712 extern snat_main_t snat_main;
 713
 714 // nat pre ed next_node feature classification
 715 extern vlib_node_registration_t nat_default_node;
 716 extern vlib_node_registration_t nat_pre_in2out_node;
 717 extern vlib_node_registration_t nat_pre_out2in_node;
 718
 719 extern vlib_node_registration_t snat_in2out_node;
 720 extern vlib_node_registration_t snat_in2out_output_node;
 721 extern vlib_node_registration_t snat_out2in_node;
 722 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
 723 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
 724 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
 725 extern vlib_node_registration_t nat44_ed_in2out_node;
 726 extern vlib_node_registration_t nat44_ed_in2out_output_node;
 727 extern vlib_node_registration_t nat44_ed_out2in_node;
 728
 729 extern fib_source_t nat_fib_src_hi;
 730 extern fib_source_t nat_fib_src_low;
 731
 732 /* format functions */
 733 format_function_t format_snat_user;
 734 format_function_t format_snat_static_mapping;
 735 format_function_t format_snat_static_map_to_resolve;
 736 format_function_t format_snat_session;
 737 format_function_t format_snat_key;
 738 format_function_t format_static_mapping_key;
 739 format_function_t format_nat_protocol;
 740 format_function_t format_nat_addr_and_port_alloc_alg;
 741 /* unformat functions */
 742 unformat_function_t unformat_nat_protocol;
 743
 744 /** \brief Check if SNAT session is created from static mapping.
 745     @param s SNAT session
 746     @return 1 if SNAT session is created from static mapping otherwise 0
 747 */
 748 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
 749
 750 /** \brief Check if SNAT session for unknown protocol.
 751     @param s SNAT session
 752     @return 1 if SNAT session for unknown protocol otherwise 0
 753 */
 754 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
 755
 756 /** \brief Check if NAT session is twice NAT.
 757     @param s NAT session
 758     @return 1 if NAT session is twice NAT
 759 */
 760 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
 761
 762 /** \brief Check if NAT session is load-balancing.
 763     @param s NAT session
 764     @return 1 if NAT session is load-balancing
 765 */
 766 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
 767
 768 /** \brief Check if NAT session is forwarding bypass.
 769     @param s NAT session
 770     @return 1 if NAT session is load-balancing
 771 */
 772 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
 773
 774 /** \brief Check if NAT session is endpoint dependent.
 775     @param s NAT session
 776     @return 1 if NAT session is endpoint dependent
 777 */
 778 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
 779
 780 /** \brief Check if NAT session has affinity record.
 781     @param s NAT session
 782     @return 1 if NAT session has affinity record
 783 */
 784 #define is_affinity_sessions(s) (s->flags & SNAT_SESSION_FLAG_AFFINITY)
 785
 786 /** \brief Check if exact pool address should be used.
 787     @param s SNAT session
 788     @return 1 if exact pool address or 0
 789 */
 790 #define is_exact_address_session(s) (s->flags & SNAT_SESSION_FLAG_EXACT_ADDRESS)
 791
 792 /** \brief Check if NAT interface is inside.
 793     @param i NAT interface
 794     @return 1 if inside interface
 795 */
 796 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
 797
 798 /** \brief Check if NAT interface is outside.
 799     @param i NAT interface
 800     @return 1 if outside interface
 801 */
 802 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
 803
 804 /** \brief Check if NAT44 endpoint-dependent TCP session is closed.
 805     @param s NAT session
 806     @return 1 if session is closed
 807 */
 808 #define nat44_is_ses_closed(s) s->state == 0xf
 809
 810 /** \brief Check if NAT static mapping is address only (1:1NAT).
 811     @param sm NAT static mapping
 812     @return 1 if 1:1NAT, 0 if 1:1NAPT
 813 */
 814 #define is_addr_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_ADDR_ONLY)
 815
 816 /** \brief Check if NAT static mapping match only out2in direction.
 817     @param sm NAT static mapping
 818     @return 1 if rule match only out2in direction
 819 */
 820 #define is_out2in_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY)
 821
 822 /** \brief Check if NAT static mapping is identity NAT.
 823     @param sm NAT static mapping
 824     @return 1 if identity NAT
 825 */
 826 #define is_identity_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT)
 827
 828 /** \brief Check if NAT static mapping is load-balancing.
 829     @param sm NAT static mapping
 830     @return 1 if load-balancing
 831 */
 832 #define is_lb_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_LB)
 833
 834 /** \brief Check if exact pool address should be used.
 835     @param s SNAT session
 836     @return 1 if exact pool address or 0
 837 */
 838 #define is_exact_address(s) (s->flags & NAT_STATIC_MAPPING_FLAG_EXACT_ADDRESS)
 839
 840 /** \brief Check if client initiating TCP connection (received SYN from client)
 841     @param t TCP header
 842     @return 1 if client initiating TCP connection
 843 */
 844 always_inline bool
 845 tcp_flags_is_init (u8 f)
 846 {
 847   return (f & TCP_FLAG_SYN) && !(f & TCP_FLAG_ACK);
 848 }
 849
 850 /* logging */
 851 #define nat_log_err(...) \
 852   vlib_log(VLIB_LOG_LEVEL_ERR, snat_main.log_class, __VA_ARGS__)
 853 #define nat_log_warn(...) \
 854   vlib_log(VLIB_LOG_LEVEL_WARNING, snat_main.log_class, __VA_ARGS__)
 855 #define nat_log_notice(...) \
 856   vlib_log(VLIB_LOG_LEVEL_NOTICE, snat_main.log_class, __VA_ARGS__)
 857 #define nat_log_info(...) \
 858   vlib_log(VLIB_LOG_LEVEL_INFO, snat_main.log_class, __VA_ARGS__)
 859 #define nat_log_debug(...)\
 860   vlib_log(VLIB_LOG_LEVEL_DEBUG, snat_main.log_class, __VA_ARGS__)
 861
 862 /* NAT API Logging Levels */
 863 #define foreach_nat_log_level \
 864   _(0x00, LOG_NONE)           \
 865   _(0x01, LOG_ERROR)          \
 866   _(0x02, LOG_WARNING)        \
 867   _(0x03, LOG_NOTICE)         \
 868   _(0x04, LOG_INFO)           \
 869   _(0x05, LOG_DEBUG)
 870
 871 typedef enum nat_log_level_t_
 872 {
 873 #define _(n,f) SNAT_##f = n,
 874   foreach_nat_log_level
 875 #undef _
 876 } nat_log_level_t;
 877
 878 #define nat_elog(_level, _str)                           \
 879 do                                                       \
 880   {                                                      \
 881     snat_main_t *sm = &snat_main;                        \
 882     if (PREDICT_FALSE (sm->log_level >= _level))         \
 883       {                                                  \
 884         ELOG_TYPE_DECLARE (e) =                          \
 885           {                                              \
 886             .format = "nat-msg " _str,                   \
 887             .format_args = "",                           \
 888           };                                             \
 889         ELOG_DATA (&vlib_global_main.elog_main, e);      \
 890       }                                                  \
 891   } while (0);
 892
 893 #define nat_elog_addr(_level, _str, _addr)               \
 894 do                                                       \
 895   {                                                      \
 896     if (PREDICT_FALSE (sm->log_level >= _level))         \
 897       {                                                  \
 898         ELOG_TYPE_DECLARE (e) =                          \
 899           {                                              \
 900             .format = "nat-msg " _str " %d.%d.%d.%d",    \
 901             .format_args = "i1i1i1i1",                   \
 902           };                                             \
 903         CLIB_PACKED(struct                               \
 904           {                                              \
 905             u8 oct1;                                     \
 906             u8 oct2;                                     \
 907             u8 oct3;                                     \
 908             u8 oct4;                                     \
 909           }) *ed;                                        \
 910         ed = ELOG_DATA (&vlib_global_main.elog_main, e); \
 911         ed->oct4 = _addr >> 24;                          \
 912         ed->oct3 = _addr >> 16;                          \
 913         ed->oct2 = _addr >> 8;                           \
 914         ed->oct1 = _addr;                                \
 915     }                                                    \
 916   } while (0);
 917
 918 #define nat_elog_debug_handoff(_str, _tid, _fib, _src, _dst)                \
 919 do                                                                          \
 920   {                                                                         \
 921   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                      \
 922     {                                                                       \
 923       ELOG_TYPE_DECLARE (e) =                                               \
 924         {                                                                   \
 925           .format = "nat-msg " _str " ip src: %d.%d.%d.%d dst: %d.%d.%d.%d" \
 926                                     " tid from: %d to: %d fib: %d",         \
 927         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                            \
 928       };                                                                    \
 929       CLIB_PACKED(struct                                                    \
 930         {                                                                   \
 931           u8 src_oct1;                                                      \
 932           u8 src_oct2;                                                      \
 933           u8 src_oct3;                                                      \
 934           u8 src_oct4;                                                      \
 935           u8 dst_oct1;                                                      \
 936           u8 dst_oct2;                                                      \
 937           u8 dst_oct3;                                                      \
 938           u8 dst_oct4;                                                      \
 939           u32 ftid;                                                         \
 940           u32 ttid;                                                         \
 941           u32 fib;                                                          \
 942         }) *ed;                                                             \
 943       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                      \
 944       ed->src_oct1 = _src >> 24;                                            \
 945       ed->src_oct2 = _src >> 16;                                            \
 946       ed->src_oct3 = _src >> 8;                                             \
 947       ed->src_oct4 = _src;                                                  \
 948       ed->dst_oct1 = _dst >> 24;                                            \
 949       ed->dst_oct2 = _dst >> 16;                                            \
 950       ed->dst_oct3 = _dst >> 8;                                             \
 951       ed->dst_oct4 = _dst;                                                  \
 952       ed->ftid = vlib_get_thread_index ();                                  \
 953       ed->ttid = _tid;                                                      \
 954       ed->fib = _fib;                                                       \
 955     }                                                                       \
 956   } while (0);
 957
 958 #define nat_elog_debug_handoff_v2(_str, _prt, _fib, _src, _dst)              \
 959 do                                                                           \
 960   {                                                                          \
 961   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                       \
 962     {                                                                        \
 963       ELOG_TYPE_DECLARE (e) =                                                \
 964         {                                                                    \
 965           .format = "nat-msg " _str " ip_src:%d.%d.%d.%d ip_dst:%d.%d.%d.%d" \
 966                                     " tid:%d prt:%d fib:%d",                 \
 967         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                             \
 968       };                                                                     \
 969       CLIB_PACKED(struct                                                     \
 970         {                                                                    \
 971           u8 src_oct1;                                                       \
 972           u8 src_oct2;                                                       \
 973           u8 src_oct3;                                                       \
 974           u8 src_oct4;                                                       \
 975           u8 dst_oct1;                                                       \
 976           u8 dst_oct2;                                                       \
 977           u8 dst_oct3;                                                       \
 978           u8 dst_oct4;                                                       \
 979           u32 tid;                                                           \
 980           u32 prt;                                                           \
 981           u32 fib;                                                           \
 982         }) *ed;                                                              \
 983       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                       \
 984       ed->src_oct1 = _src >> 24;                                             \
 985       ed->src_oct2 = _src >> 16;                                             \
 986       ed->src_oct3 = _src >> 8;                                              \
 987       ed->src_oct4 = _src;                                                   \
 988       ed->dst_oct1 = _dst >> 24;                                             \
 989       ed->dst_oct2 = _dst >> 16;                                             \
 990       ed->dst_oct3 = _dst >> 8;                                              \
 991       ed->dst_oct4 = _dst;                                                   \
 992       ed->tid = vlib_get_thread_index ();                                    \
 993       ed->prt = _prt;                                                        \
 994       ed->fib = _fib;                                                        \
 995     }                                                                        \
 996   } while (0);
 997
 998 #define nat_elog_X1(_level, _fmt, _arg, _val1)            \
 999 do                                                        \
1000   {                                                       \
1001     snat_main_t *sm = &snat_main;                         \
1002     if (PREDICT_FALSE (sm->log_level >= _level))          \
1003       {                                                   \
1004         ELOG_TYPE_DECLARE (e) =                           \
1005           {                                               \
1006             .format = "nat-msg " _fmt,                    \
1007             .format_args = _arg,                          \
1008           };                                              \
1009         CLIB_PACKED(struct                                \
1010           {                                               \
1011             typeof (_val1) val1;                          \
1012           }) *ed;                                         \
1013         ed = ELOG_DATA (&vlib_global_main.elog_main, e);  \
1014         ed->val1 = _val1;                                 \
1015       }                                                   \
1016   } while (0);
1017
1018 #define nat_elog_notice(nat_elog_str) \
1019   nat_elog(SNAT_LOG_INFO, "[notice] " nat_elog_str)
1020 #define nat_elog_warn(nat_elog_str) \
1021   nat_elog(SNAT_LOG_WARNING, "[warning] " nat_elog_str)
1022 #define nat_elog_err(nat_elog_str) \
1023   nat_elog(SNAT_LOG_ERROR, "[error] " nat_elog_str)
1024 #define nat_elog_debug(nat_elog_str) \
1025   nat_elog(SNAT_LOG_DEBUG, "[debug] " nat_elog_str)
1026 #define nat_elog_info(nat_elog_str) \
1027   nat_elog(SNAT_LOG_INFO, "[info] " nat_elog_str)
1028
1029 #define nat_elog_notice_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1030   nat_elog_X1(SNAT_LOG_NOTICE, "[notice] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1031 #define nat_elog_warn_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1032   nat_elog_X1(SNAT_LOG_WARNING, "[warning] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1033 #define nat_elog_err_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1034   nat_elog_X1(SNAT_LOG_ERROR, "[error] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1035 #define nat_elog_debug_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1036   nat_elog_X1(SNAT_LOG_DEBUG, "[debug] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1037 #define nat_elog_info_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1038   nat_elog_X1(SNAT_LOG_INFO, "[info] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1039
1040 /* ICMP session match functions */
1041 u32 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1042                             u32 thread_index, vlib_buffer_t * b0,
1043                             ip4_header_t * ip0, ip4_address_t * addr,
1044                             u16 * port, u32 * fib_index,
1045                             nat_protocol_t * proto, void *d, void *e,
1046                             u8 * dont_translate);
1047 u32 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1048                             u32 thread_index, vlib_buffer_t * b0,
1049                             ip4_header_t * ip0, ip4_address_t * addr,
1050                             u16 * port, u32 * fib_index,
1051                             nat_protocol_t * proto, void *d, void *e,
1052                             u8 * dont_translate);
1053 u32 icmp_match_out2in_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1054                             u32 thread_index, vlib_buffer_t * b0,
1055                             ip4_header_t * ip0, ip4_address_t * addr,
1056                             u16 * port, u32 * fib_index,
1057                             nat_protocol_t * proto, void *d, void *e,
1058                             u8 * dont_translate);
1059 u32 icmp_match_out2in_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1060                             u32 thread_index, vlib_buffer_t * b0,
1061                             ip4_header_t * ip0, ip4_address_t * addr,
1062                             u16 * port, u32 * fib_index,
1063                             nat_protocol_t * proto, void *d, void *e,
1064                             u8 * dont_translate);
1065
1066 /* ICMP endpoint-dependent session match functions */
1067 u32 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1068                           u32 thread_index, vlib_buffer_t * b0,
1069                           ip4_header_t * ip0, ip4_address_t * addr,
1070                           u16 * port, u32 * fib_index, nat_protocol_t * proto,
1071                           void *d, void *e, u8 * dont_translate);
1072 u32 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1073                           u32 thread_index, vlib_buffer_t * b0,
1074                           ip4_header_t * ip0, ip4_address_t * addr,
1075                           u16 * port, u32 * fib_index, nat_protocol_t * proto,
1076                           void *d, void *e, u8 * dont_translate);
1077
1078 u32 icmp_in2out (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1079                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1080                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1081                  void *d, void *e);
1082
1083 u32 icmp_out2in (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1084                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1085                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1086                  void *d, void *e);
1087
1088 /* hairpinning functions */
1089 u32 snat_icmp_hairpinning (snat_main_t * sm, vlib_buffer_t * b0,
1090                            ip4_header_t * ip0, icmp46_header_t * icmp0,
1091                            int is_ed);
1092 void nat_hairpinning_sm_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1093                                        ip4_header_t * ip);
1094 void nat44_ed_hairpinning_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1095                                          ip4_header_t * ip);
1096 int snat_hairpinning (vlib_main_t * vm, vlib_node_runtime_t * node,
1097                       snat_main_t * sm, vlib_buffer_t * b0,
1098                       ip4_header_t * ip0, udp_header_t * udp0,
1099                       tcp_header_t * tcp0, u32 proto0, int is_ed,
1100                       int do_trace);
1101
1102 /* Call back functions for clib_bihash_add_or_overwrite_stale */
1103 int nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1104 int nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1105 int nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1106 int nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1107
1108 /**
1109  * @brief Add external address to NAT44 pool
1110  *
1111  * @param sm        snat global configuration data
1112  * @param addr      IPv4 address
1113  * @param vrf_id    VRF id of tenant, ~0 means independent of VRF
1114  * @param twice_nat 1 if twice NAT address
1115  *
1116  * @return 0 on success, non-zero value otherwise
1117  */
1118 int snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
1119                       u8 twice_nat);
1120
1121 /**
1122  * @brief Delete external address from NAT44 pool
1123  *
1124  * @param sm        snat global configuration data
1125  * @param addr      IPv4 address
1126  * @param delete_sm 1 if delete static mapping using address
1127  * @param twice_nat 1 if twice NAT address
1128  *
1129  * @return 0 on success, non-zero value otherwise
1130  */
1131 int snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
1132                       u8 twice_nat);
1133
1134 /**
1135  * @brief Add/delete external address to FIB DPO (out2in DPO mode)
1136  *
1137  * @param addr   IPv4 address
1138  * @param is_add 1 = add, 0 = delete
1139  *
1140  * @return 0 on success, non-zero value otherwise
1141  */
1142 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
1143
1144 /**
1145  * @brief Add/delete NAT44 static mapping
1146  *
1147  * @param l_addr       local IPv4 address
1148  * @param e_addr       external IPv4 address
1149  * @param l_port       local port number
1150  * @param e_port       external port number
1151  * @param vrf_id       local VRF ID
1152  * @param addr_only    1 = 1:1NAT, 0 = 1:1NAPT
1153  * @param sw_if_index  use interface address as external IPv4 address
1154  * @param proto        L4 protocol
1155  * @param is_add       1 = add, 0 = delete
1156  * @param twice_nat    twice-nat mode
1157  * @param out2in_only  if 1 rule match only out2in direction
1158  * @param tag          opaque string tag
1159  * @param identity_nat identity NAT
1160  * @param pool_addr    pool IPv4 address
1161  * @param exact        1 = exact pool address
1162  *
1163  * @return 0 on success, non-zero value otherwise
1164  */
1165 int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
1166                              u16 l_port, u16 e_port, u32 vrf_id,
1167                              int addr_only, u32 sw_if_index,
1168                              nat_protocol_t proto, int is_add,
1169                              twice_nat_type_t twice_nat, u8 out2in_only,
1170                              u8 * tag, u8 identity_nat,
1171                              ip4_address_t pool_addr, int exact);
1172
1173 /**
1174  * @brief Add/delete static mapping with load-balancing (multiple backends)
1175  *
1176  * @param e_addr      external IPv4 address
1177  * @param e_port      external port number
1178  * @param proto       L4 protocol
1179  * @param locals      list of local backends
1180  * @param is_add      1 = add, 0 = delete
1181  * @param twice_nat   twice-nat mode
1182  * @param out2in_only if 1 rule match only out2in direction
1183  * @param tag         opaque string tag
1184  * @param affinity    0 = disabled, otherwise client IP affinity sticky time
1185  *
1186  * @return 0 on success, non-zero value otherwise
1187  */
1188 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
1189                                      nat_protocol_t proto,
1190                                      nat44_lb_addr_port_t * locals, u8 is_add,
1191                                      twice_nat_type_t twice_nat,
1192                                      u8 out2in_only, u8 * tag, u32 affinity);
1193
1194 int nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
1195                                            ip4_address_t l_addr, u16 l_port,
1196                                            nat_protocol_t proto, u32 vrf_id,
1197                                            u8 probability, u8 is_add);
1198
1199 clib_error_t *snat_api_init (vlib_main_t * vm, snat_main_t * sm);
1200
1201 /**
1202  * @brief Set NAT plugin workers
1203  *
1204  * @param bitmap NAT workers bitmap
1205  *
1206  * @return 0 on success, non-zero value otherwise
1207  */
1208 int snat_set_workers (uword * bitmap);
1209
1210 /**
1211  * @brief Enable/disable NAT44 feature on the interface
1212  *
1213  * @param sw_if_index software index of the interface
1214  * @param is_inside   1 = inside, 0 = outside
1215  * @param is_del      1 = delete, 0 = add
1216  *
1217  * @return 0 on success, non-zero value otherwise
1218  */
1219 int snat_interface_add_del (u32 sw_if_index, u8 is_inside, int is_del);
1220
1221 /**
1222  * @brief Enable/disable NAT44 output feature on the interface (postrouting NAT)
1223  *
1224  * @param sw_if_index software index of the interface
1225  * @param is_inside   1 = inside, 0 = outside
1226  * @param is_del      1 = delete, 0 = add
1227  *
1228  * @return 0 on success, non-zero value otherwise
1229  */
1230 int snat_interface_add_del_output_feature (u32 sw_if_index, u8 is_inside,
1231                                            int is_del);
1232
1233 /**
1234  * @brief Add/delete NAT44 pool address from specific interface
1235  *
1236  * @param sw_if_index software index of the interface
1237  * @param is_del      1 = delete, 0 = add
1238  * @param twice_nat   1 = twice NAT address for external hosts
1239  *
1240  * @return 0 on success, non-zero value otherwise
1241  */
1242 int snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
1243                                 u8 twice_nat);
1244
1245 /**
1246  * @brief Delete NAT44 session
1247  *
1248  * @param addr   IPv4 address
1249  * @param port   L4 port number
1250  * @param proto  L4 protocol
1251  * @param vrf_id VRF ID
1252  * @param is_in  1 = inside network address and port pair, 0 = outside
1253  *
1254  * @return 0 on success, non-zero value otherwise
1255  */
1256 int nat44_del_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1257                        nat_protocol_t proto, u32 vrf_id, int is_in);
1258
1259 /**
1260  * @brief Delete NAT44 endpoint-dependent session
1261  *
1262  * @param sm     snat global configuration data
1263  * @param addr   IPv4 address
1264  * @param port   L4 port number
1265  * @param proto  L4 protocol
1266  * @param vrf_id VRF ID
1267  * @param is_in  1 = inside network address and port pair, 0 = outside
1268  *
1269  * @return 0 on success, non-zero value otherwise
1270  */
1271 int nat44_del_ed_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1272                           ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1273                           u32 vrf_id, int is_in);
1274
1275 /**
1276  * @brief Free NAT44 session data (lookup keys, external address port)
1277  *
1278  * @param sm           snat global configuration data
1279  * @param s            NAT session
1280  * @param thread_index thread index
1281  * @param is_ha        is HA event
1282  */
1283 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
1284                             u32 thread_index, u8 is_ha);
1285
1286 /**
1287  * @brief Set NAT44 session limit (session limit, vrf id)
1288  *
1289  * @param session_limit Session limit
1290  * @param vrf_id        VRF id
1291  * @return 0 on success, non-zero value otherwise
1292  */
1293 int nat44_set_session_limit (u32 session_limit, u32 vrf_id);
1294
1295 /**
1296  * @brief Update NAT44 session limit flushing all data (session limit, vrf id)
1297  *
1298  * @param session_limit Session limit
1299  * @param vrf_id        VRF id
1300  * @return 0 on success, non-zero value otherwise
1301  */
1302 int nat44_update_session_limit (u32 session_limit, u32 vrf_id);
1303 /**
1304  * @brief Free NAT44 ED session data (lookup keys, external address port)
1305  *
1306  * @param s            NAT session
1307  * @param thread_index thread index
1308  * @param is_ha        is HA event
1309  */
1310 void
1311 nat44_free_session_data (snat_main_t * sm, snat_session_t * s,
1312                          u32 thread_index, u8 is_ha);
1313
1314 /**
1315  * @brief Initialize NAT44 data
1316  *
1317  * @param tsm          per thread data
1318  */
1319 void nat44_db_init (snat_main_per_thread_data_t * tsm);
1320
1321 /**
1322  * @brief Free NAT44 data
1323  *
1324  * @param tsm          per thread data
1325  */
1326 void nat44_db_free (snat_main_per_thread_data_t * tsm);
1327
1328 void nat44_sessions_clear ();
1329
1330 /**
1331  * @brief Find or create NAT user
1332  *
1333  * @param sm           snat global configuration data
1334  * @param addr         IPv4 address
1335  * @param fib_index    FIB table index
1336  * @param thread_index thread index
1337  *
1338  * @return NAT user data structure on success otherwise zero value
1339  */
1340 snat_user_t *nat_user_get_or_create (snat_main_t * sm,
1341                                      ip4_address_t * addr, u32 fib_index,
1342                                      u32 thread_index);
1343
1344 /**
1345  * @brief Allocate new NAT session or recycle last used
1346  *
1347  * @param sm           snat global configuration data
1348  * @param u            NAT user
1349  * @param thread_index thread index
1350  * @param now          time now
1351  *
1352  * @return session data structure on success otherwise zero value
1353  */
1354 snat_session_t *nat_session_alloc_or_recycle (snat_main_t * sm,
1355                                               snat_user_t * u,
1356                                               u32 thread_index, f64 now);
1357
1358 /**
1359  * @brief Set address and port assignment algorithm for MAP-E CE
1360  *
1361  * @param psid        Port Set Identifier value
1362  * @param psid_offset number of offset bits
1363  * @param psid_length length of PSID
1364  */
1365 void nat_set_alloc_addr_and_port_mape (u16 psid, u16 psid_offset,
1366                                        u16 psid_length);
1367
1368 /**
1369  * @brief Set address and port assignment algorithm for port range
1370  *
1371  * @param start_port beginning of the port range
1372  * @param end_port   end of the port range
1373  */
1374 void nat_set_alloc_addr_and_port_range (u16 start_port, u16 end_port);
1375
1376 /**
1377  * @brief Set address and port assignment algorithm to default/standard
1378  */
1379 void nat_set_alloc_addr_and_port_default (void);
1380
1381 /**
1382  * @brief Free outside address and port pair
1383  *
1384  * @param addresses    vector of outside addresses
1385  * @param thread_index thread index
1386  * @param key          address, port and protocol
1387  */
1388 void
1389 snat_free_outside_address_and_port (snat_address_t * addresses,
1390                                     u32 thread_index,
1391                                     ip4_address_t * addr,
1392                                     u16 port, nat_protocol_t protocol);
1393
1394 /**
1395  * @brief Alloc outside address and port
1396  *
1397  * @param addresses         vector of outside addresses
1398  * @param fib_index         FIB table index
1399  * @param thread_index      thread index
1400  * @param port_per_thread   number of ports per thread
1401  * @param snat_thread_index NAT thread index
1402  *
1403  * @return 0 on success, non-zero value otherwise
1404  */
1405 int snat_alloc_outside_address_and_port (snat_address_t * addresses,
1406                                          u32 fib_index,
1407                                          u32 thread_index,
1408                                          nat_protocol_t proto,
1409                                          ip4_address_t * addr,
1410                                          u16 * port,
1411                                          u16 port_per_thread,
1412                                          u32 snat_thread_index);
1413
1414 void expire_per_vrf_sessions (u32 fib_index);
1415
1416 /**
1417  * @brief Match NAT44 static mapping.
1418  *
1419  * @param key             address and port to match
1420  * @param addr            external/local address of the matched mapping
1421  * @param port            port of the matched mapping
1422  * @param fib_index       fib index of the matched mapping
1423  * @param by_external     if 0 match by local address otherwise match by external
1424  *                        address
1425  * @param is_addr_only    1 if matched mapping is address only
1426  * @param twice_nat       matched mapping is twice NAT type
1427  * @param lb              1 if matched mapping is load-balanced
1428  * @param ext_host_addr   external host address
1429  * @param is_identity_nat 1 if indentity mapping
1430  * @param out             if !=0 set to pointer of the mapping structure
1431  *
1432  * @returns 0 if match found otherwise 1.
1433  */
1434 int snat_static_mapping_match (snat_main_t * sm,
1435                                ip4_address_t match_addr,
1436                                u16 match_port,
1437                                u32 match_fib_index,
1438                                nat_protocol_t match_protocol,
1439                                ip4_address_t * mapping_addr,
1440                                u16 * mapping_port,
1441                                u32 * mapping_fib_index,
1442                                u8 by_external,
1443                                u8 * is_addr_only,
1444                                twice_nat_type_t * twice_nat,
1445                                lb_nat_type_t * lb,
1446                                ip4_address_t * ext_host_addr,
1447                                u8 * is_identity_nat,
1448                                snat_static_mapping_t ** out);
1449
1450 /**
1451  * @brief Add/del NAT address to FIB.
1452  *
1453  * Add the external NAT address to the FIB as receive entries. This ensures
1454  * that VPP will reply to ARP for this address and we don't need to enable
1455  * proxy ARP on the outside interface.
1456  *
1457  * @param addr        IPv4 address
1458  * @param plen        address prefix length
1459  * @param sw_if_index software index of the outside interface
1460  * @param is_add      0 = delete, 1 = add.
1461  */
1462 void snat_add_del_addr_to_fib (ip4_address_t * addr,
1463                                u8 p_len, u32 sw_if_index, int is_add);
1464
1465 /*
1466  * Why is this here? Because we don't need to touch this layer to
1467  * simply reply to an icmp. We need to change id to a unique
1468  * value to NAT an echo request/reply.
1469  */
1470
1471 typedef struct
1472 {
1473   u16 identifier;
1474   u16 sequence;
1475 } icmp_echo_header_t;
1476
1477 typedef struct
1478 {
1479   u16 src_port, dst_port;
1480 } tcp_udp_header_t;
1481
1482 u8 *format_user_kvp (u8 * s, va_list * args);
1483
1484 #endif /* __included_nat_h__ */
1485 /*
1486  * fd.io coding-style-patch-verification: ON
1487  *
1488  * Local Variables:
1489  * eval: (c-set-style "gnu")
1490  * End:
1491  */