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
  37 /* default session timeouts */
  38 #define SNAT_UDP_TIMEOUT 300
  39 #define SNAT_TCP_TRANSITORY_TIMEOUT 240
  40 #define SNAT_TCP_ESTABLISHED_TIMEOUT 7440
  41 #define SNAT_ICMP_TIMEOUT 60
  42
  43 /* number of worker handoff frame queue elements */
  44 #define NAT_FQ_NELTS 64
  45
  46 /* NAT buffer flags */
  47 #define SNAT_FLAG_HAIRPINNING (1 << 0)
  48
  49 typedef enum
  50 {
  51   NAT_NEXT_DROP,
  52   NAT_NEXT_ICMP_ERROR,
  53   NAT_NEXT_IN2OUT_ED_FAST_PATH,
  54   NAT_NEXT_IN2OUT_ED_SLOW_PATH,
  55   NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH,
  56   NAT_NEXT_OUT2IN_ED_FAST_PATH,
  57   NAT_NEXT_OUT2IN_ED_SLOW_PATH,
  58   NAT_NEXT_IN2OUT_CLASSIFY,
  59   NAT_NEXT_OUT2IN_CLASSIFY,
  60   NAT_N_NEXT,
  61 } nat_next_t;
  62
  63 typedef struct
  64 {
  65   u32 next_index;
  66   u32 arc_next_index;
  67 } nat_pre_trace_t;
  68
  69 /* session key (4-tuple) */
  70 typedef struct
  71 {
  72   union
  73   {
  74     struct
  75     {
  76       ip4_address_t addr;
  77       u16 port;
  78       u16 protocol:3, fib_index:13;
  79     };
  80     u64 as_u64;
  81   };
  82 } snat_session_key_t;
  83
  84 /* deterministic session outside key */
  85 typedef struct
  86 {
  87   union
  88   {
  89     struct
  90     {
  91       ip4_address_t ext_host_addr;
  92       u16 ext_host_port;
  93       u16 out_port;
  94     };
  95     u64 as_u64;
  96   };
  97 } snat_det_out_key_t;
  98
  99 /* user (internal host) key */
 100 typedef struct
 101 {
 102   union
 103   {
 104     struct
 105     {
 106       ip4_address_t addr;
 107       u32 fib_index;
 108     };
 109     u64 as_u64;
 110   };
 111 } snat_user_key_t;
 112
 113 /* NAT API Configuration flags */
 114 #define foreach_nat_config_flag \
 115   _(0x01, IS_TWICE_NAT)         \
 116   _(0x02, IS_SELF_TWICE_NAT)    \
 117   _(0x04, IS_OUT2IN_ONLY)       \
 118   _(0x08, IS_ADDR_ONLY)         \
 119   _(0x10, IS_OUTSIDE)           \
 120   _(0x20, IS_INSIDE)            \
 121   _(0x40, IS_STATIC)            \
 122   _(0x80, IS_EXT_HOST_VALID)    \
 123
 124 typedef enum nat_config_flags_t_
 125 {
 126 #define _(n,f) NAT_API_##f = n,
 127   foreach_nat_config_flag
 128 #undef _
 129 } nat_config_flags_t;
 130
 131 /* External address and port allocation modes */
 132 #define foreach_nat_addr_and_port_alloc_alg \
 133   _(0, DEFAULT, "default")         \
 134   _(1, MAPE, "map-e")              \
 135   _(2, RANGE, "port-range")
 136
 137 typedef enum
 138 {
 139 #define _(v, N, s) NAT_ADDR_AND_PORT_ALLOC_ALG_##N = v,
 140   foreach_nat_addr_and_port_alloc_alg
 141 #undef _
 142 } nat_addr_and_port_alloc_alg_t;
 143
 144
 145 /* Supported L4 protocols */
 146 #define foreach_snat_protocol \
 147   _(UDP, 0, udp, "udp")       \
 148   _(TCP, 1, tcp, "tcp")       \
 149   _(ICMP, 2, icmp, "icmp")
 150
 151 typedef enum
 152 {
 153 #define _(N, i, n, s) SNAT_PROTOCOL_##N = i,
 154   foreach_snat_protocol
 155 #undef _
 156 } snat_protocol_t;
 157
 158
 159 /* Session state */
 160 #define foreach_snat_session_state          \
 161   _(0, UNKNOWN, "unknown")                 \
 162   _(1, UDP_ACTIVE, "udp-active")           \
 163   _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
 164   _(3, TCP_ESTABLISHED, "tcp-established") \
 165   _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
 166   _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
 167   _(6, TCP_CLOSING, "tcp-closing")         \
 168   _(7, TCP_LAST_ACK, "tcp-last-ack")       \
 169   _(8, TCP_CLOSED, "tcp-closed")           \
 170   _(9, ICMP_ACTIVE, "icmp-active")
 171
 172 typedef enum
 173 {
 174 #define _(v, N, s) SNAT_SESSION_##N = v,
 175   foreach_snat_session_state
 176 #undef _
 177 } snat_session_state_t;
 178
 179 #define foreach_nat_in2out_ed_error                     \
 180 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 181 _(IN2OUT_PACKETS, "good in2out packets processed")      \
 182 _(OUT_OF_PORTS, "out of ports")                         \
 183 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 184 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 185 _(MAX_USER_SESS_EXCEEDED, "max user sessions exceeded") \
 186 _(DROP_FRAGMENT, "drop fragment")                       \
 187 _(CANNOT_CREATE_USER, "cannot create NAT user")         \
 188 _(NON_SYN, "non-SYN packet try to create session")      \
 189 _(TCP_PACKETS, "TCP packets")                           \
 190 _(TCP_CLOSED, "drops due to TCP in transitory timeout") \
 191 _(UDP_PACKETS, "UDP packets")                           \
 192 _(ICMP_PACKETS, "ICMP packets")                         \
 193 _(OTHER_PACKETS, "other protocol packets")              \
 194 _(FRAGMENTS, "fragments")                               \
 195 _(CACHED_FRAGMENTS, "cached fragments")                 \
 196 _(PROCESSED_FRAGMENTS, "processed fragments")
 197
 198 typedef enum
 199 {
 200 #define _(sym,str) NAT_IN2OUT_ED_ERROR_##sym,
 201   foreach_nat_in2out_ed_error
 202 #undef _
 203     NAT_IN2OUT_ED_N_ERROR,
 204 } nat_in2out_ed_error_t;
 205
 206 #define foreach_nat_out2in_ed_error                     \
 207 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 208 _(OUT2IN_PACKETS, "good out2in packets processed")      \
 209 _(OUT_OF_PORTS, "out of ports")                         \
 210 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 211 _(NO_TRANSLATION, "no translation")                     \
 212 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 213 _(MAX_USER_SESS_EXCEEDED, "max user sessions exceeded") \
 214 _(DROP_FRAGMENT, "drop fragment")                       \
 215 _(CANNOT_CREATE_USER, "cannot create NAT user")         \
 216 _(NON_SYN, "non-SYN packet try to create session")      \
 217 _(TCP_PACKETS, "TCP packets")                           \
 218 _(TCP_CLOSED, "drops due to TCP in transitory timeout") \
 219 _(UDP_PACKETS, "UDP packets")                           \
 220 _(ICMP_PACKETS, "ICMP packets")                         \
 221 _(OTHER_PACKETS, "other protocol packets")              \
 222 _(FRAGMENTS, "fragments")                               \
 223 _(CACHED_FRAGMENTS, "cached fragments")                 \
 224 _(PROCESSED_FRAGMENTS, "processed fragments")
 225
 226 typedef enum
 227 {
 228 #define _(sym,str) NAT_OUT2IN_ED_ERROR_##sym,
 229   foreach_nat_out2in_ed_error
 230 #undef _
 231     NAT_OUT2IN_ED_N_ERROR,
 232 } nat_out2in_ed_error_t;
 233
 234
 235 /* Endpoint dependent TCP session state */
 236 #define NAT44_SES_I2O_FIN 1
 237 #define NAT44_SES_O2I_FIN 2
 238 #define NAT44_SES_I2O_FIN_ACK 4
 239 #define NAT44_SES_O2I_FIN_ACK 8
 240 #define NAT44_SES_I2O_SYN 16
 241 #define NAT44_SES_O2I_SYN 32
 242 #define NAT44_SES_RST     64
 243
 244 /* Session flags */
 245 #define SNAT_SESSION_FLAG_STATIC_MAPPING       1
 246 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO        2
 247 #define SNAT_SESSION_FLAG_LOAD_BALANCING       4
 248 #define SNAT_SESSION_FLAG_TWICE_NAT            8
 249 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT   16
 250 #define SNAT_SESSION_FLAG_FWD_BYPASS           32
 251 #define SNAT_SESSION_FLAG_AFFINITY             64
 252 #define SNAT_SESSION_FLAG_OUTPUT_FEATURE       128
 253
 254 /* NAT interface flags */
 255 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
 256 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
 257
 258 /* Static mapping flags */
 259 #define NAT_STATIC_MAPPING_FLAG_ADDR_ONLY    1
 260 #define NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY  2
 261 #define NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT 4
 262 #define NAT_STATIC_MAPPING_FLAG_LB           8
 263
 264 /* *INDENT-OFF* */
 265 typedef CLIB_PACKED(struct
 266 {
 267   /* Outside network key */
 268   snat_session_key_t out2in;
 269
 270   /* Inside network key */
 271   snat_session_key_t in2out;
 272
 273   /* Flags */
 274   u32 flags;
 275
 276   /* Per-user translations */
 277   u32 per_user_index;
 278   u32 per_user_list_head_index;
 279
 280   /* index in global LRU list */
 281   u32 global_lru_index;
 282   f64 last_lru_update;
 283
 284   /* Last heard timer */
 285   f64 last_heard;
 286
 287   /* Last HA refresh */
 288   f64 ha_last_refreshed;
 289
 290   /* Counters */
 291   u64 total_bytes;
 292   u32 total_pkts;
 293
 294   /* External host address and port */
 295   ip4_address_t ext_host_addr;
 296   u16 ext_host_port;
 297
 298   /* External host address and port after translation */
 299   ip4_address_t ext_host_nat_addr;
 300   u16 ext_host_nat_port;
 301
 302   /* TCP session state */
 303   u8 state;
 304   u32 i2o_fin_seq;
 305   u32 o2i_fin_seq;
 306   u32 tcp_close_timestamp;
 307
 308   /* user index */
 309   u32 user_index;
 310 }) snat_session_t;
 311 /* *INDENT-ON* */
 312
 313
 314 typedef struct
 315 {
 316   ip4_address_t addr;
 317   u32 fib_index;
 318   u32 sessions_per_user_list_head_index;
 319   u32 nsessions;
 320   u32 nstaticsessions;
 321 } snat_user_t;
 322
 323 typedef struct
 324 {
 325   ip4_address_t addr;
 326   u32 fib_index;
 327 /* *INDENT-OFF* */
 328 #define _(N, i, n, s) \
 329   u16 busy_##n##_ports; \
 330   u16 * busy_##n##_ports_per_thread; \
 331   u32 busy_##n##_port_refcounts[65535];
 332   foreach_snat_protocol
 333 #undef _
 334 /* *INDENT-ON* */
 335 } snat_address_t;
 336
 337 typedef struct
 338 {
 339   u32 fib_index;
 340   u32 refcount;
 341 } nat_outside_fib_t;
 342
 343 typedef struct
 344 {
 345   /* Inside network port */
 346   u16 in_port;
 347   /* Outside network address and port */
 348   snat_det_out_key_t out;
 349   /* Session state */
 350   u8 state;
 351   /* Expire timeout */
 352   u32 expire;
 353 } snat_det_session_t;
 354
 355 typedef struct
 356 {
 357   /* inside IP address range */
 358   ip4_address_t in_addr;
 359   u8 in_plen;
 360   /* outside IP address range */
 361   ip4_address_t out_addr;
 362   u8 out_plen;
 363   /* inside IP addresses / outside IP addresses */
 364   u32 sharing_ratio;
 365   /* number of ports available to internal host */
 366   u16 ports_per_host;
 367   /* session counter */
 368   u32 ses_num;
 369   /* vector of sessions */
 370   snat_det_session_t *sessions;
 371 } snat_det_map_t;
 372
 373 typedef struct
 374 {
 375   /* backend IP address */
 376   ip4_address_t addr;
 377   /* backend port number */
 378   u16 port;
 379   /* probability of the backend to be randomly matched */
 380   u8 probability;
 381   u8 prefix;
 382   /* backend FIB table */
 383   u32 vrf_id;
 384   u32 fib_index;
 385 } nat44_lb_addr_port_t;
 386
 387 typedef enum
 388 {
 389   /* twice-nat disabled */
 390   TWICE_NAT_DISABLED,
 391   /* twice-nat enabled */
 392   TWICE_NAT,
 393   /* twice-nat only when src IP equals dst IP after translation */
 394   TWICE_NAT_SELF,
 395 } twice_nat_type_t;
 396
 397 typedef enum
 398 {
 399   /* no load-balancing */
 400   NO_LB_NAT,
 401   /* load-balancing */
 402   LB_NAT,
 403   /* load-balancing with affinity */
 404   AFFINITY_LB_NAT,
 405 } lb_nat_type_t;
 406
 407 typedef struct
 408 {
 409   /* local IP address */
 410   ip4_address_t local_addr;
 411   /* external IP address */
 412   ip4_address_t external_addr;
 413   /* local port */
 414   u16 local_port;
 415   /* external port */
 416   u16 external_port;
 417   /* is twice-nat */
 418   twice_nat_type_t twice_nat;
 419   /* local FIB table */
 420   u32 vrf_id;
 421   u32 fib_index;
 422   /* protocol */
 423   snat_protocol_t proto;
 424   /* 0 = disabled, otherwise client IP affinity sticky time in seconds */
 425   u32 affinity;
 426   /* worker threads used by backends/local host */
 427   u32 *workers;
 428   /* opaque string tag */
 429   u8 *tag;
 430   /* backends for load-balancing mode */
 431   nat44_lb_addr_port_t *locals;
 432   /* affinity per service lis */
 433   u32 affinity_per_service_list_head_index;
 434   /* flags */
 435   u32 flags;
 436 } snat_static_mapping_t;
 437
 438 typedef struct
 439 {
 440   u32 sw_if_index;
 441   u8 flags;
 442 } snat_interface_t;
 443
 444 typedef struct
 445 {
 446   ip4_address_t l_addr;
 447   u16 l_port;
 448   u16 e_port;
 449   u32 sw_if_index;
 450   u32 vrf_id;
 451   snat_protocol_t proto;
 452   u32 flags;
 453   int addr_only;
 454   int twice_nat;
 455   int is_add;
 456   int out2in_only;
 457   int identity_nat;
 458   u8 *tag;
 459 } snat_static_map_resolve_t;
 460
 461 typedef struct
 462 {
 463   /* Main lookup tables */
 464   clib_bihash_8_8_t out2in;
 465   clib_bihash_8_8_t in2out;
 466
 467   /* Endpoint dependent sessions lookup tables */
 468   clib_bihash_16_8_t out2in_ed;
 469   clib_bihash_16_8_t in2out_ed;
 470
 471   /* Find-a-user => src address lookup */
 472   clib_bihash_8_8_t user_hash;
 473
 474   /* User pool */
 475   snat_user_t *users;
 476
 477   /* Session pool */
 478   snat_session_t *sessions;
 479
 480   /* Pool of doubly-linked list elements */
 481   dlist_elt_t *list_pool;
 482
 483   /* LRU session list - head is stale, tail is fresh */
 484   dlist_elt_t *global_lru_pool;
 485   u32 global_lru_head_index;
 486
 487   /* NAT thread index */
 488   u32 snat_thread_index;
 489
 490   /* real thread index */
 491   u32 thread_index;
 492
 493 } snat_main_per_thread_data_t;
 494
 495 struct snat_main_s;
 496
 497 /* ICMP session match function */
 498 typedef u32 (snat_icmp_match_function_t) (struct snat_main_s * sm,
 499                                           vlib_node_runtime_t * node,
 500                                           u32 thread_index,
 501                                           vlib_buffer_t * b0,
 502                                           ip4_header_t * ip0, u8 * p_proto,
 503                                           snat_session_key_t * p_value,
 504                                           u8 * p_dont_translate, void *d,
 505                                           void *e);
 506
 507 /* Return worker thread index for given packet */
 508 typedef u32 (snat_get_worker_in2out_function_t) (ip4_header_t * ip,
 509                                                  u32 rx_fib_index,
 510                                                  u8 is_output);
 511
 512 typedef u32 (snat_get_worker_out2in_function_t) (vlib_buffer_t * b,
 513                                                  ip4_header_t * ip,
 514                                                  u32 rx_fib_index,
 515                                                  u8 is_output);
 516
 517 /* NAT address and port allocation function */
 518 typedef int (nat_alloc_out_addr_and_port_function_t) (snat_address_t *
 519                                                       addresses,
 520                                                       u32 fib_index,
 521                                                       u32 thread_index,
 522                                                       snat_session_key_t * k,
 523                                                       u16 port_per_thread,
 524                                                       u32 snat_thread_index);
 525
 526
 527 typedef struct snat_main_s
 528 {
 529   /* ICMP session match functions */
 530   snat_icmp_match_function_t *icmp_match_in2out_cb;
 531   snat_icmp_match_function_t *icmp_match_out2in_cb;
 532
 533   /* Thread settings */
 534   u32 num_workers;
 535   u32 first_worker_index;
 536   u32 *workers;
 537   snat_get_worker_in2out_function_t *worker_in2out_cb;
 538   snat_get_worker_out2in_function_t *worker_out2in_cb;
 539   u16 port_per_thread;
 540   u32 num_snat_thread;
 541
 542   /* Per thread data */
 543   snat_main_per_thread_data_t *per_thread_data;
 544
 545   /* Find a static mapping by local */
 546   clib_bihash_8_8_t static_mapping_by_local;
 547
 548   /* Find a static mapping by external */
 549   clib_bihash_8_8_t static_mapping_by_external;
 550
 551   /* Static mapping pool */
 552   snat_static_mapping_t *static_mappings;
 553
 554   /* Interface pool */
 555   snat_interface_t *interfaces;
 556   snat_interface_t *output_feature_interfaces;
 557
 558   /* Vector of outside addresses */
 559   snat_address_t *addresses;
 560   /* Address and port allocation function */
 561   nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
 562   /* Address and port allocation type */
 563   nat_addr_and_port_alloc_alg_t addr_and_port_alloc_alg;
 564   /* Port set parameters (MAP-E) */
 565   u8 psid_offset;
 566   u8 psid_length;
 567   u16 psid;
 568   /* Port range parameters */
 569   u16 start_port;
 570   u16 end_port;
 571
 572   /* vector of outside fibs */
 573   nat_outside_fib_t *outside_fibs;
 574
 575   /* Vector of twice NAT addresses for external hosts */
 576   snat_address_t *twice_nat_addresses;
 577
 578   /* sw_if_indices whose intfc addresses should be auto-added */
 579   u32 *auto_add_sw_if_indices;
 580   u32 *auto_add_sw_if_indices_twice_nat;
 581
 582   /* vector of interface address static mappings to resolve. */
 583   snat_static_map_resolve_t *to_resolve;
 584
 585   /* Randomize port allocation order */
 586   u32 random_seed;
 587
 588   /* Worker handoff frame-queue index */
 589   u32 fq_in2out_index;
 590   u32 fq_in2out_output_index;
 591   u32 fq_out2in_index;
 592
 593   /* node indexes */
 594   u32 error_node_index;
 595
 596   /* handoff fq nodes  */
 597   u32 handoff_out2in_index;
 598   u32 handoff_in2out_index;
 599   u32 handoff_in2out_output_index;
 600
 601   /* respect feature arc nodes */
 602   u32 pre_out2in_node_index;
 603   u32 pre_in2out_node_index;
 604
 605   u32 in2out_node_index;
 606   u32 in2out_output_node_index;
 607   u32 in2out_fast_node_index;
 608   u32 in2out_slowpath_node_index;
 609   u32 in2out_slowpath_output_node_index;
 610   u32 ed_in2out_node_index;
 611   u32 ed_in2out_slowpath_node_index;
 612   u32 out2in_node_index;
 613   u32 out2in_fast_node_index;
 614   u32 ed_out2in_node_index;
 615   u32 ed_out2in_slowpath_node_index;
 616   u32 det_in2out_node_index;
 617   u32 det_out2in_node_index;
 618
 619   u32 hairpinning_node_index;
 620   u32 hairpin_dst_node_index;
 621   u32 hairpin_src_node_index;
 622   u32 ed_hairpinning_node_index;
 623   u32 ed_hairpin_dst_node_index;
 624   u32 ed_hairpin_src_node_index;
 625
 626
 627   /* Deterministic NAT mappings */
 628   snat_det_map_t *det_maps;
 629
 630   /* If forwarding is enabled */
 631   u8 forwarding_enabled;
 632
 633   /* Config parameters */
 634   u8 static_mapping_only;
 635   u8 static_mapping_connection_tracking;
 636   u8 deterministic;
 637   u8 out2in_dpo;
 638   u8 endpoint_dependent;
 639
 640   u32 translation_buckets;
 641   uword translation_memory_size;
 642   u32 max_translations;
 643   u32 *max_translations_per_fib;
 644
 645   u32 user_buckets;
 646   uword user_memory_size;
 647   u32 max_translations_per_user;
 648
 649   u32 outside_vrf_id;
 650   u32 outside_fib_index;
 651   u32 inside_vrf_id;
 652   u32 inside_fib_index;
 653
 654   /* values of various timeouts */
 655   // proto timeouts
 656   u32 udp_timeout;
 657   u32 tcp_transitory_timeout;
 658   u32 tcp_established_timeout;
 659   u32 icmp_timeout;
 660
 661   /* TCP MSS clamping */
 662   u16 mss_clamping;
 663   u16 mss_value_net;
 664
 665   /* counters/gauges */
 666   vlib_simple_counter_main_t total_users;
 667   vlib_simple_counter_main_t total_sessions;
 668
 669   /* API message ID base */
 670   u16 msg_id_base;
 671
 672   /* log class */
 673   vlib_log_class_t log_class;
 674   /* logging level */
 675   u8 log_level;
 676
 677   /* convenience */
 678   vnet_main_t *vnet_main;
 679   ip4_main_t *ip4_main;
 680   ip_lookup_main_t *ip4_lookup_main;
 681   api_main_t *api_main;
 682 } snat_main_t;
 683
 684 typedef struct
 685 {
 686   u32 thread_index;
 687   f64 now;
 688 } nat44_is_idle_session_ctx_t;
 689
 690 typedef struct
 691 {
 692   u32 cached_sw_if_index;
 693   u32 cached_ip4_address;
 694 } snat_runtime_t;
 695
 696 extern snat_main_t snat_main;
 697
 698 // nat pre ed next_node feature classification
 699 extern vlib_node_registration_t nat_default_node;
 700 extern vlib_node_registration_t nat_pre_in2out_node;
 701 extern vlib_node_registration_t nat_pre_out2in_node;
 702
 703 extern vlib_node_registration_t snat_in2out_node;
 704 extern vlib_node_registration_t snat_in2out_output_node;
 705 extern vlib_node_registration_t snat_out2in_node;
 706 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
 707 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
 708 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
 709 extern vlib_node_registration_t snat_det_in2out_node;
 710 extern vlib_node_registration_t snat_det_out2in_node;
 711 extern vlib_node_registration_t nat44_ed_in2out_node;
 712 extern vlib_node_registration_t nat44_ed_in2out_output_node;
 713 extern vlib_node_registration_t nat44_ed_out2in_node;
 714
 715 extern fib_source_t nat_fib_src_hi;
 716 extern fib_source_t nat_fib_src_low;
 717
 718 /* format functions */
 719 format_function_t format_snat_user;
 720 format_function_t format_snat_static_mapping;
 721 format_function_t format_snat_static_map_to_resolve;
 722 format_function_t format_snat_session;
 723 format_function_t format_det_map_ses;
 724 format_function_t format_snat_key;
 725 format_function_t format_static_mapping_key;
 726 format_function_t format_snat_protocol;
 727 format_function_t format_nat_addr_and_port_alloc_alg;
 728 /* unformat functions */
 729 unformat_function_t unformat_snat_protocol;
 730
 731 /** \brief Check if SNAT session is created from static mapping.
 732     @param s SNAT session
 733     @return 1 if SNAT session is created from static mapping otherwise 0
 734 */
 735 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
 736
 737 /** \brief Check if SNAT session for unknown protocol.
 738     @param s SNAT session
 739     @return 1 if SNAT session for unknown protocol otherwise 0
 740 */
 741 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
 742
 743 /** \brief Check if NAT session is twice NAT.
 744     @param s NAT session
 745     @return 1 if NAT session is twice NAT
 746 */
 747 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
 748
 749 /** \brief Check if NAT session is load-balancing.
 750     @param s NAT session
 751     @return 1 if NAT session is load-balancing
 752 */
 753 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
 754
 755 /** \brief Check if NAT session is forwarding bypass.
 756     @param s NAT session
 757     @return 1 if NAT session is load-balancing
 758 */
 759 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
 760
 761 /** \brief Check if NAT session is endpoint dependent.
 762     @param s NAT session
 763     @return 1 if NAT session is endpoint dependent
 764 */
 765 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
 766
 767 /** \brief Check if NAT session has affinity record.
 768     @param s NAT session
 769     @return 1 if NAT session has affinity record
 770 */
 771 #define is_affinity_sessions(s) (s->flags & SNAT_SESSION_FLAG_AFFINITY)
 772
 773 /** \brief Check if NAT interface is inside.
 774     @param i NAT interface
 775     @return 1 if inside interface
 776 */
 777 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
 778
 779 /** \brief Check if NAT interface is outside.
 780     @param i NAT interface
 781     @return 1 if outside interface
 782 */
 783 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
 784
 785 /** \brief Check if NAT44 endpoint-dependent TCP session is closed.
 786     @param s NAT session
 787     @return 1 if session is closed
 788 */
 789 #define nat44_is_ses_closed(s) s->state == 0xf
 790
 791 /** \brief Check if NAT static mapping is address only (1:1NAT).
 792     @param sm NAT static mapping
 793     @return 1 if 1:1NAT, 0 if 1:1NAPT
 794 */
 795 #define is_addr_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_ADDR_ONLY)
 796
 797 /** \brief Check if NAT static mapping match only out2in direction.
 798     @param sm NAT static mapping
 799     @return 1 if rule match only out2in direction
 800 */
 801 #define is_out2in_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY)
 802
 803 /** \brief Check if NAT static mapping is identity NAT.
 804     @param sm NAT static mapping
 805     @return 1 if identity NAT
 806 */
 807 #define is_identity_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT)
 808
 809 /** \brief Check if NAT static mapping is load-balancing.
 810     @param sm NAT static mapping
 811     @return 1 if load-balancing
 812 */
 813 #define is_lb_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_LB)
 814
 815 /** \brief Check if client initiating TCP connection (received SYN from client)
 816     @param t TCP header
 817     @return 1 if client initiating TCP connection
 818 */
 819 always_inline bool
 820 tcp_flags_is_init (u8 f)
 821 {
 822   return (f & TCP_FLAG_SYN) && !(f & TCP_FLAG_ACK);
 823 }
 824
 825 /* logging */
 826 #define nat_log_err(...) \
 827   vlib_log(VLIB_LOG_LEVEL_ERR, snat_main.log_class, __VA_ARGS__)
 828 #define nat_log_warn(...) \
 829   vlib_log(VLIB_LOG_LEVEL_WARNING, snat_main.log_class, __VA_ARGS__)
 830 #define nat_log_notice(...) \
 831   vlib_log(VLIB_LOG_LEVEL_NOTICE, snat_main.log_class, __VA_ARGS__)
 832 #define nat_log_info(...) \
 833   vlib_log(VLIB_LOG_LEVEL_INFO, snat_main.log_class, __VA_ARGS__)
 834 #define nat_log_debug(...)\
 835   vlib_log(VLIB_LOG_LEVEL_DEBUG, snat_main.log_class, __VA_ARGS__)
 836
 837 /* NAT API Logging Levels */
 838 #define foreach_nat_log_level \
 839   _(0x00, LOG_NONE)           \
 840   _(0x01, LOG_ERROR)          \
 841   _(0x02, LOG_WARNING)        \
 842   _(0x03, LOG_NOTICE)         \
 843   _(0x04, LOG_INFO)           \
 844   _(0x05, LOG_DEBUG)
 845
 846 typedef enum nat_log_level_t_
 847 {
 848 #define _(n,f) SNAT_##f = n,
 849   foreach_nat_log_level
 850 #undef _
 851 } nat_log_level_t;
 852
 853 #define nat_elog(_level, _str)                           \
 854 do                                                       \
 855   {                                                      \
 856     snat_main_t *sm = &snat_main;                        \
 857     if (PREDICT_FALSE (sm->log_level >= _level))         \
 858       {                                                  \
 859         ELOG_TYPE_DECLARE (e) =                          \
 860           {                                              \
 861             .format = "nat-msg " _str,                   \
 862             .format_args = "",                           \
 863           };                                             \
 864         ELOG_DATA (&vlib_global_main.elog_main, e);      \
 865       }                                                  \
 866   } while (0);
 867
 868 #define nat_elog_addr(_level, _str, _addr)               \
 869 do                                                       \
 870   {                                                      \
 871     if (PREDICT_FALSE (sm->log_level >= _level))         \
 872       {                                                  \
 873         ELOG_TYPE_DECLARE (e) =                          \
 874           {                                              \
 875             .format = "nat-msg " _str " %d.%d.%d.%d",    \
 876             .format_args = "i1i1i1i1",                   \
 877           };                                             \
 878         CLIB_PACKED(struct                               \
 879           {                                              \
 880             u8 oct1;                                     \
 881             u8 oct2;                                     \
 882             u8 oct3;                                     \
 883             u8 oct4;                                     \
 884           }) *ed;                                        \
 885         ed = ELOG_DATA (&vlib_global_main.elog_main, e); \
 886         ed->oct4 = _addr >> 24;                          \
 887         ed->oct3 = _addr >> 16;                          \
 888         ed->oct2 = _addr >> 8;                           \
 889         ed->oct1 = _addr;                                \
 890     }                                                    \
 891   } while (0);
 892
 893 #define nat_elog_debug_handoff(_str, _tid, _fib, _src, _dst)                \
 894 do                                                                          \
 895   {                                                                         \
 896   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                      \
 897     {                                                                       \
 898       ELOG_TYPE_DECLARE (e) =                                               \
 899         {                                                                   \
 900           .format = "nat-msg " _str " ip src: %d.%d.%d.%d dst: %d.%d.%d.%d" \
 901                                     " tid from: %d to: %d fib: %d",         \
 902         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                            \
 903       };                                                                    \
 904       CLIB_PACKED(struct                                                    \
 905         {                                                                   \
 906           u8 src_oct1;                                                      \
 907           u8 src_oct2;                                                      \
 908           u8 src_oct3;                                                      \
 909           u8 src_oct4;                                                      \
 910           u8 dst_oct1;                                                      \
 911           u8 dst_oct2;                                                      \
 912           u8 dst_oct3;                                                      \
 913           u8 dst_oct4;                                                      \
 914           u32 ftid;                                                         \
 915           u32 ttid;                                                         \
 916           u32 fib;                                                          \
 917         }) *ed;                                                             \
 918       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                      \
 919       ed->src_oct1 = _src >> 24;                                            \
 920       ed->src_oct2 = _src >> 16;                                            \
 921       ed->src_oct3 = _src >> 8;                                             \
 922       ed->src_oct4 = _src;                                                  \
 923       ed->dst_oct1 = _dst >> 24;                                            \
 924       ed->dst_oct2 = _dst >> 16;                                            \
 925       ed->dst_oct3 = _dst >> 8;                                             \
 926       ed->dst_oct4 = _dst;                                                  \
 927       ed->ftid = vlib_get_thread_index ();                                  \
 928       ed->ttid = _tid;                                                      \
 929       ed->fib = _fib;                                                       \
 930     }                                                                       \
 931   } while (0);
 932
 933 #define nat_elog_debug_handoff_v2(_str, _prt, _fib, _src, _dst)              \
 934 do                                                                           \
 935   {                                                                          \
 936   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                       \
 937     {                                                                        \
 938       ELOG_TYPE_DECLARE (e) =                                                \
 939         {                                                                    \
 940           .format = "nat-msg " _str " ip_src:%d.%d.%d.%d ip_dst:%d.%d.%d.%d" \
 941                                     " tid:%d prt:%d fib:%d",                 \
 942         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                             \
 943       };                                                                     \
 944       CLIB_PACKED(struct                                                     \
 945         {                                                                    \
 946           u8 src_oct1;                                                       \
 947           u8 src_oct2;                                                       \
 948           u8 src_oct3;                                                       \
 949           u8 src_oct4;                                                       \
 950           u8 dst_oct1;                                                       \
 951           u8 dst_oct2;                                                       \
 952           u8 dst_oct3;                                                       \
 953           u8 dst_oct4;                                                       \
 954           u32 tid;                                                           \
 955           u32 prt;                                                           \
 956           u32 fib;                                                           \
 957         }) *ed;                                                              \
 958       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                       \
 959       ed->src_oct1 = _src >> 24;                                             \
 960       ed->src_oct2 = _src >> 16;                                             \
 961       ed->src_oct3 = _src >> 8;                                              \
 962       ed->src_oct4 = _src;                                                   \
 963       ed->dst_oct1 = _dst >> 24;                                             \
 964       ed->dst_oct2 = _dst >> 16;                                             \
 965       ed->dst_oct3 = _dst >> 8;                                              \
 966       ed->dst_oct4 = _dst;                                                   \
 967       ed->tid = vlib_get_thread_index ();                                    \
 968       ed->prt = _prt;                                                        \
 969       ed->fib = _fib;                                                        \
 970     }                                                                        \
 971   } while (0);
 972
 973 #define nat_elog_X1(_level, _fmt, _arg, _val1)            \
 974 do                                                        \
 975   {                                                       \
 976     snat_main_t *sm = &snat_main;                         \
 977     if (PREDICT_FALSE (sm->log_level >= _level))          \
 978       {                                                   \
 979         ELOG_TYPE_DECLARE (e) =                           \
 980           {                                               \
 981             .format = "nat-msg " _fmt,                    \
 982             .format_args = _arg,                          \
 983           };                                              \
 984         CLIB_PACKED(struct                                \
 985           {                                               \
 986             typeof (_val1) val1;                          \
 987           }) *ed;                                         \
 988         ed = ELOG_DATA (&vlib_global_main.elog_main, e);  \
 989         ed->val1 = _val1;                                 \
 990       }                                                   \
 991   } while (0);
 992
 993 #define nat_elog_notice(nat_elog_str) \
 994   nat_elog(SNAT_LOG_INFO, "[notice] " nat_elog_str)
 995 #define nat_elog_warn(nat_elog_str) \
 996   nat_elog(SNAT_LOG_WARNING, "[warning] " nat_elog_str)
 997 #define nat_elog_err(nat_elog_str) \
 998   nat_elog(SNAT_LOG_ERROR, "[error] " nat_elog_str)
 999 #define nat_elog_debug(nat_elog_str) \
1000   nat_elog(SNAT_LOG_DEBUG, "[debug] " nat_elog_str)
1001 #define nat_elog_info(nat_elog_str) \
1002   nat_elog(SNAT_LOG_INFO, "[info] " nat_elog_str)
1003
1004 #define nat_elog_notice_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1005   nat_elog_X1(SNAT_LOG_NOTICE, "[notice] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1006 #define nat_elog_warn_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1007   nat_elog_X1(SNAT_LOG_WARNING, "[warning] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1008 #define nat_elog_err_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1009   nat_elog_X1(SNAT_LOG_ERROR, "[error] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1010 #define nat_elog_debug_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1011   nat_elog_X1(SNAT_LOG_DEBUG, "[debug] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1012 #define nat_elog_info_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1013   nat_elog_X1(SNAT_LOG_INFO, "[info] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1014
1015 /* ICMP session match functions */
1016 u32 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1017                             u32 thread_index, vlib_buffer_t * b0,
1018                             ip4_header_t * ip0, u8 * p_proto,
1019                             snat_session_key_t * p_value,
1020                             u8 * p_dont_translate, void *d, void *e);
1021 u32 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1022                             u32 thread_index, vlib_buffer_t * b0,
1023                             ip4_header_t * ip0, u8 * p_proto,
1024                             snat_session_key_t * p_value,
1025                             u8 * p_dont_translate, void *d, void *e);
1026 u32 icmp_match_out2in_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1027                             u32 thread_index, vlib_buffer_t * b0,
1028                             ip4_header_t * ip0, u8 * p_proto,
1029                             snat_session_key_t * p_value,
1030                             u8 * p_dont_translate, void *d, void *e);
1031 u32 icmp_match_out2in_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1032                             u32 thread_index, vlib_buffer_t * b0,
1033                             ip4_header_t * ip0, u8 * p_proto,
1034                             snat_session_key_t * p_value,
1035                             u8 * p_dont_translate, void *d, void *e);
1036
1037 /* ICMP deterministic NAT session match functions */
1038 u32 icmp_match_out2in_det (snat_main_t * sm, vlib_node_runtime_t * node,
1039                            u32 thread_index, vlib_buffer_t * b0,
1040                            ip4_header_t * ip0, u8 * p_proto,
1041                            snat_session_key_t * p_value,
1042                            u8 * p_dont_translate, void *d, void *e);
1043 u32 icmp_match_in2out_det (snat_main_t * sm, vlib_node_runtime_t * node,
1044                            u32 thread_index, vlib_buffer_t * b0,
1045                            ip4_header_t * ip0, u8 * p_proto,
1046                            snat_session_key_t * p_value,
1047                            u8 * p_dont_translate, void *d, void *e);
1048
1049 /* ICMP endpoint-dependent session match functions */
1050 u32 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1051                           u32 thread_index, vlib_buffer_t * b0,
1052                           ip4_header_t * ip0, u8 * p_proto,
1053                           snat_session_key_t * p_value,
1054                           u8 * p_dont_translate, void *d, void *e);
1055 u32 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1056                           u32 thread_index, vlib_buffer_t * b0,
1057                           ip4_header_t * ip0, u8 * p_proto,
1058                           snat_session_key_t * p_value,
1059                           u8 * p_dont_translate, void *d, void *e);
1060
1061 u32 icmp_in2out (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1062                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1063                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1064                  void *d, void *e);
1065
1066 u32 icmp_out2in (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1067                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1068                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1069                  void *d, void *e);
1070
1071 /* hairpinning functions */
1072 u32 snat_icmp_hairpinning (snat_main_t * sm, vlib_buffer_t * b0,
1073                            ip4_header_t * ip0, icmp46_header_t * icmp0,
1074                            int is_ed);
1075 void nat_hairpinning_sm_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1076                                        ip4_header_t * ip);
1077 void nat44_ed_hairpinning_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1078                                          ip4_header_t * ip);
1079 int snat_hairpinning (snat_main_t * sm, vlib_buffer_t * b0,
1080                       ip4_header_t * ip0, udp_header_t * udp0,
1081                       tcp_header_t * tcp0, u32 proto0, int is_ed);
1082
1083 /* Call back functions for clib_bihash_add_or_overwrite_stale */
1084 int nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1085 int nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1086 int nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1087 int nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1088
1089 /**
1090  * @brief Add external address to NAT44 pool
1091  *
1092  * @param sm        snat global configuration data
1093  * @param addr      IPv4 address
1094  * @param vrf_id    VRF id of tenant, ~0 means independent of VRF
1095  * @param twice_nat 1 if twice NAT address
1096  *
1097  * @return 0 on success, non-zero value otherwise
1098  */
1099 int snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
1100                       u8 twice_nat);
1101
1102 /**
1103  * @brief Delete external address from NAT44 pool
1104  *
1105  * @param sm        snat global configuration data
1106  * @param addr      IPv4 address
1107  * @param delete_sm 1 if delete static mapping using address
1108  * @param twice_nat 1 if twice NAT address
1109  *
1110  * @return 0 on success, non-zero value otherwise
1111  */
1112 int snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
1113                       u8 twice_nat);
1114
1115 /**
1116  * @brief Add/delete external address to FIB DPO (out2in DPO mode)
1117  *
1118  * @param addr   IPv4 address
1119  * @param is_add 1 = add, 0 = delete
1120  *
1121  * @return 0 on success, non-zero value otherwise
1122  */
1123 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
1124
1125 /**
1126  * @brief Add/delete NAT44 static mapping
1127  *
1128  * @param l_addr       local IPv4 address
1129  * @param e_addr       external IPv4 address
1130  * @param l_port       local port number
1131  * @param e_port       external port number
1132  * @param vrf_id       local VRF ID
1133  * @param addr_only    1 = 1:1NAT, 0 = 1:1NAPT
1134  * @param sw_if_index  use interface address as external IPv4 address
1135  * @param proto        L4 protocol
1136  * @param is_add       1 = add, 0 = delete
1137  * @param twice_nat    twice-nat mode
1138  * @param out2in_only  if 1 rule match only out2in direction
1139  * @param tag          opaque string tag
1140  * @param identity_nat identity NAT
1141  *
1142  * @return 0 on success, non-zero value otherwise
1143  */
1144 int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
1145                              u16 l_port, u16 e_port, u32 vrf_id,
1146                              int addr_only, u32 sw_if_index,
1147                              snat_protocol_t proto, int is_add,
1148                              twice_nat_type_t twice_nat, u8 out2in_only,
1149                              u8 * tag, u8 identity_nat);
1150
1151 /**
1152  * @brief Add/delete static mapping with load-balancing (multiple backends)
1153  *
1154  * @param e_addr      external IPv4 address
1155  * @param e_port      external port number
1156  * @param proto       L4 protocol
1157  * @param locals      list of local backends
1158  * @param is_add      1 = add, 0 = delete
1159  * @param twice_nat   twice-nat mode
1160  * @param out2in_only if 1 rule match only out2in direction
1161  * @param tag         opaque string tag
1162  * @param affinity    0 = disabled, otherwise client IP affinity sticky time
1163  *
1164  * @return 0 on success, non-zero value otherwise
1165  */
1166 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
1167                                      snat_protocol_t proto,
1168                                      nat44_lb_addr_port_t * locals, u8 is_add,
1169                                      twice_nat_type_t twice_nat,
1170                                      u8 out2in_only, u8 * tag, u32 affinity);
1171
1172 int nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
1173                                            ip4_address_t l_addr, u16 l_port,
1174                                            snat_protocol_t proto, u32 vrf_id,
1175                                            u8 probability, u8 is_add);
1176
1177 clib_error_t *snat_api_init (vlib_main_t * vm, snat_main_t * sm);
1178
1179 /**
1180  * @brief Set NAT plugin workers
1181  *
1182  * @param bitmap NAT workers bitmap
1183  *
1184  * @return 0 on success, non-zero value otherwise
1185  */
1186 int snat_set_workers (uword * bitmap);
1187
1188 /**
1189  * @brief Enable/disable NAT44 feature on the interface
1190  *
1191  * @param sw_if_index software index of the interface
1192  * @param is_inside   1 = inside, 0 = outside
1193  * @param is_del      1 = delete, 0 = add
1194  *
1195  * @return 0 on success, non-zero value otherwise
1196  */
1197 int snat_interface_add_del (u32 sw_if_index, u8 is_inside, int is_del);
1198
1199 /**
1200  * @brief Enable/disable NAT44 output feature on the interface (postrouting NAT)
1201  *
1202  * @param sw_if_index software index of the interface
1203  * @param is_inside   1 = inside, 0 = outside
1204  * @param is_del      1 = delete, 0 = add
1205  *
1206  * @return 0 on success, non-zero value otherwise
1207  */
1208 int snat_interface_add_del_output_feature (u32 sw_if_index, u8 is_inside,
1209                                            int is_del);
1210
1211 /**
1212  * @brief Add/delete NAT44 pool address from specific interface
1213  *
1214  * @param sw_if_index software index of the interface
1215  * @param is_del      1 = delete, 0 = add
1216  * @param twice_nat   1 = twice NAT address for external hosts
1217  *
1218  * @return 0 on success, non-zero value otherwise
1219  */
1220 int snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
1221                                 u8 twice_nat);
1222
1223 /**
1224  * @brief Delete NAT44 session
1225  *
1226  * @param addr   IPv4 address
1227  * @param port   L4 port number
1228  * @param proto  L4 protocol
1229  * @param vrf_id VRF ID
1230  * @param is_in  1 = inside network address and port pair, 0 = outside
1231  *
1232  * @return 0 on success, non-zero value otherwise
1233  */
1234 int nat44_del_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1235                        snat_protocol_t proto, u32 vrf_id, int is_in);
1236
1237 /**
1238  * @brief Delete NAT44 endpoint-dependent session
1239  *
1240  * @param sm     snat global configuration data
1241  * @param addr   IPv4 address
1242  * @param port   L4 port number
1243  * @param proto  L4 protocol
1244  * @param vrf_id VRF ID
1245  * @param is_in  1 = inside network address and port pair, 0 = outside
1246  *
1247  * @return 0 on success, non-zero value otherwise
1248  */
1249 int nat44_del_ed_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1250                           ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1251                           u32 vrf_id, int is_in);
1252
1253 /**
1254  * @brief Free NAT44 session data (lookup keys, external address port)
1255  *
1256  * @param sm           snat global configuration data
1257  * @param s            NAT session
1258  * @param thread_index thread index
1259  * @param is_ha        is HA event
1260  */
1261 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
1262                             u32 thread_index, u8 is_ha);
1263
1264 /**
1265  * @brief Set NAT44 session limit (session limit, vrf id)
1266  *
1267  * @param session_limit Session limit
1268  * @param vrf_id        VRF id
1269  * @return 0 on success, non-zero value otherwise
1270  */
1271 int nat44_set_session_limit (u32 session_limit, u32 vrf_id);
1272
1273 /**
1274  * @brief Free NAT44 ED session data (lookup keys, external address port)
1275  *
1276  * @param s            NAT session
1277  * @param thread_index thread index
1278  * @param is_ha        is HA event
1279  */
1280 void
1281 nat44_free_session_data (snat_main_t * sm, snat_session_t * s,
1282                          u32 thread_index, u8 is_ha);
1283
1284 /**
1285  * @brief Initialize NAT44 data
1286  *
1287  * @param tsm          per thread data
1288  */
1289 void nat44_db_init (snat_main_per_thread_data_t * tsm);
1290
1291 /**
1292  * @brief Free NAT44 data
1293  *
1294  * @param tsm          per thread data
1295  */
1296 void nat44_db_free (snat_main_per_thread_data_t * tsm);
1297
1298 /**
1299  * @brief Find or create NAT user
1300  *
1301  * @param sm           snat global configuration data
1302  * @param addr         IPv4 address
1303  * @param fib_index    FIB table index
1304  * @param thread_index thread index
1305  *
1306  * @return NAT user data structure on success otherwise zero value
1307  */
1308 snat_user_t *nat_user_get_or_create (snat_main_t * sm,
1309                                      ip4_address_t * addr, u32 fib_index,
1310                                      u32 thread_index);
1311
1312 /**
1313  * @brief Allocate new NAT session or recycle last used
1314  *
1315  * @param sm           snat global configuration data
1316  * @param u            NAT user
1317  * @param thread_index thread index
1318  * @param now          time now
1319  *
1320  * @return session data structure on success otherwise zero value
1321  */
1322 snat_session_t *nat_session_alloc_or_recycle (snat_main_t * sm,
1323                                               snat_user_t * u,
1324                                               u32 thread_index, f64 now);
1325
1326 /**
1327  * @brief Allocate NAT endpoint-dependent session
1328  *
1329  * @param sm           snat global configuration data
1330  * @param thread_index thread index
1331  * @param now          time now
1332  *
1333  * @return session data structure on success otherwise zero value
1334  */
1335 snat_session_t *nat_ed_session_alloc (snat_main_t * sm, u32 thread_index,
1336                                       f64 now);
1337
1338 /**
1339  * @brief Set address and port assignment algorithm for MAP-E CE
1340  *
1341  * @param psid        Port Set Identifier value
1342  * @param psid_offset number of offset bits
1343  * @param psid_length length of PSID
1344  */
1345 void nat_set_alloc_addr_and_port_mape (u16 psid, u16 psid_offset,
1346                                        u16 psid_length);
1347
1348 /**
1349  * @brief Set address and port assignment algorithm for port range
1350  *
1351  * @param start_port beginning of the port range
1352  * @param end_port   end of the port range
1353  */
1354 void nat_set_alloc_addr_and_port_range (u16 start_port, u16 end_port);
1355
1356 /**
1357  * @brief Set address and port assignment algorithm to default/standard
1358  */
1359 void nat_set_alloc_addr_and_port_default (void);
1360
1361 /**
1362  * @brief Free outside address and port pair
1363  *
1364  * @param addresses    vector of outside addresses
1365  * @param thread_index thread index
1366  * @param k            address, port and protocol
1367  */
1368 void snat_free_outside_address_and_port (snat_address_t * addresses,
1369                                          u32 thread_index,
1370                                          snat_session_key_t * k);
1371
1372 /**
1373  * @brief Alloc outside address and port
1374  *
1375  * @param addresses         vector of outside addresses
1376  * @param fib_index         FIB table index
1377  * @param thread_index      thread index
1378  * @param k                 allocated address and port pair
1379  * @param port_per_thread   number of ports per thread
1380  * @param snat_thread_index NAT thread index
1381  *
1382  * @return 0 on success, non-zero value otherwise
1383  */
1384 int snat_alloc_outside_address_and_port (snat_address_t * addresses,
1385                                          u32 fib_index,
1386                                          u32 thread_index,
1387                                          snat_session_key_t * k,
1388                                          u16 port_per_thread,
1389                                          u32 snat_thread_index);
1390
1391 /**
1392  * @brief Match NAT44 static mapping.
1393  *
1394  * @param match         address and port to match
1395  * @param mapping       external/local address and port of the matched mapping
1396  * @param by_external   if 0 match by local address otherwise match by external
1397  *                      address
1398  * @param is_addr_only  1 if matched mapping is address only
1399  * @param twice_nat     matched mapping is twice NAT type
1400  * @param lb            1 if matched mapping is load-balanced
1401  * @param ext_host_addr external host address
1402  *
1403  * @returns 0 if match found otherwise 1.
1404  */
1405 int snat_static_mapping_match (snat_main_t * sm,
1406                                snat_session_key_t match,
1407                                snat_session_key_t * mapping,
1408                                u8 by_external,
1409                                u8 * is_addr_only,
1410                                twice_nat_type_t * twice_nat,
1411                                lb_nat_type_t * lb,
1412                                ip4_address_t * ext_host_addr,
1413                                u8 * is_identity_nat);
1414
1415 /**
1416  * @brief Add/del NAT address to FIB.
1417  *
1418  * Add the external NAT address to the FIB as receive entries. This ensures
1419  * that VPP will reply to ARP for this address and we don't need to enable
1420  * proxy ARP on the outside interface.
1421  *
1422  * @param addr        IPv4 address
1423  * @param plen        address prefix length
1424  * @param sw_if_index software index of the outside interface
1425  * @param is_add      0 = delete, 1 = add.
1426  */
1427 void snat_add_del_addr_to_fib (ip4_address_t * addr,
1428                                u8 p_len, u32 sw_if_index, int is_add);
1429
1430 /*
1431  * Why is this here? Because we don't need to touch this layer to
1432  * simply reply to an icmp. We need to change id to a unique
1433  * value to NAT an echo request/reply.
1434  */
1435
1436 typedef struct
1437 {
1438   u16 identifier;
1439   u16 sequence;
1440 } icmp_echo_header_t;
1441
1442 typedef struct
1443 {
1444   u16 src_port, dst_port;
1445 } tcp_udp_header_t;
1446
1447 int nat_global_lru_free_one (snat_main_t * sm, int thread_index, f64 now);
1448
1449 #endif /* __included_nat_h__ */
1450 /*
1451  * fd.io coding-style-patch-verification: ON
1452  *
1453  * Local Variables:
1454  * eval: (c-set-style "gnu")
1455  * End:
1456  */