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_SLOW_PATH,
  58   NAT_NEXT_OUT2IN_ED_FAST_PATH,
  59   NAT_NEXT_OUT2IN_ED_SLOW_PATH,
  60   NAT_NEXT_IN2OUT_CLASSIFY,
  61   NAT_NEXT_OUT2IN_CLASSIFY,
  62   NAT_N_NEXT,
  63 } nat_next_t;
  64
  65 typedef struct
  66 {
  67   u32 next_index;
  68   u32 arc_next_index;
  69 } nat_pre_trace_t;
  70
  71 /* session key (4-tuple) */
  72 typedef struct
  73 {
  74   union
  75   {
  76     struct
  77     {
  78       ip4_address_t addr;
  79       u16 port;
  80       u16 protocol:3, fib_index:13;
  81     };
  82     u64 as_u64;
  83   };
  84 } snat_session_key_t;
  85
  86 /* deterministic session outside key */
  87 typedef struct
  88 {
  89   union
  90   {
  91     struct
  92     {
  93       ip4_address_t ext_host_addr;
  94       u16 ext_host_port;
  95       u16 out_port;
  96     };
  97     u64 as_u64;
  98   };
  99 } snat_det_out_key_t;
 100
 101 /* user (internal host) key */
 102 typedef struct
 103 {
 104   union
 105   {
 106     struct
 107     {
 108       ip4_address_t addr;
 109       u32 fib_index;
 110     };
 111     u64 as_u64;
 112   };
 113 } snat_user_key_t;
 114
 115 /* NAT API Configuration flags */
 116 #define foreach_nat_config_flag \
 117   _(0x01, IS_TWICE_NAT)         \
 118   _(0x02, IS_SELF_TWICE_NAT)    \
 119   _(0x04, IS_OUT2IN_ONLY)       \
 120   _(0x08, IS_ADDR_ONLY)         \
 121   _(0x10, IS_OUTSIDE)           \
 122   _(0x20, IS_INSIDE)            \
 123   _(0x40, IS_STATIC)            \
 124   _(0x80, IS_EXT_HOST_VALID)    \
 125
 126 typedef enum nat_config_flags_t_
 127 {
 128 #define _(n,f) NAT_API_##f = n,
 129   foreach_nat_config_flag
 130 #undef _
 131 } nat_config_flags_t;
 132
 133 /* External address and port allocation modes */
 134 #define foreach_nat_addr_and_port_alloc_alg \
 135   _(0, DEFAULT, "default")         \
 136   _(1, MAPE, "map-e")              \
 137   _(2, RANGE, "port-range")
 138
 139 typedef enum
 140 {
 141 #define _(v, N, s) NAT_ADDR_AND_PORT_ALLOC_ALG_##N = v,
 142   foreach_nat_addr_and_port_alloc_alg
 143 #undef _
 144 } nat_addr_and_port_alloc_alg_t;
 145
 146 /* Session state */
 147 #define foreach_snat_session_state          \
 148   _(0, UNKNOWN, "unknown")                 \
 149   _(1, UDP_ACTIVE, "udp-active")           \
 150   _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
 151   _(3, TCP_ESTABLISHED, "tcp-established") \
 152   _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
 153   _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
 154   _(6, TCP_CLOSING, "tcp-closing")         \
 155   _(7, TCP_LAST_ACK, "tcp-last-ack")       \
 156   _(8, TCP_CLOSED, "tcp-closed")           \
 157   _(9, ICMP_ACTIVE, "icmp-active")
 158
 159 typedef enum
 160 {
 161 #define _(v, N, s) SNAT_SESSION_##N = v,
 162   foreach_snat_session_state
 163 #undef _
 164 } snat_session_state_t;
 165
 166 #define foreach_nat_in2out_ed_error                     \
 167 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 168 _(IN2OUT_PACKETS, "good in2out packets processed")      \
 169 _(OUT_OF_PORTS, "out of ports")                         \
 170 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 171 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 172 _(MAX_USER_SESS_EXCEEDED, "max user sessions exceeded") \
 173 _(DROP_FRAGMENT, "drop fragment")                       \
 174 _(CANNOT_CREATE_USER, "cannot create NAT user")         \
 175 _(NON_SYN, "non-SYN packet try to create session")      \
 176 _(TCP_PACKETS, "TCP packets")                           \
 177 _(TCP_CLOSED, "drops due to TCP in transitory timeout") \
 178 _(UDP_PACKETS, "UDP packets")                           \
 179 _(ICMP_PACKETS, "ICMP packets")                         \
 180 _(OTHER_PACKETS, "other protocol packets")              \
 181 _(FRAGMENTS, "fragments")                               \
 182 _(CACHED_FRAGMENTS, "cached fragments")                 \
 183 _(PROCESSED_FRAGMENTS, "processed fragments")
 184
 185 typedef enum
 186 {
 187 #define _(sym,str) NAT_IN2OUT_ED_ERROR_##sym,
 188   foreach_nat_in2out_ed_error
 189 #undef _
 190     NAT_IN2OUT_ED_N_ERROR,
 191 } nat_in2out_ed_error_t;
 192
 193 #define foreach_nat_out2in_ed_error                     \
 194 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
 195 _(OUT2IN_PACKETS, "good out2in packets processed")      \
 196 _(OUT_OF_PORTS, "out of ports")                         \
 197 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 198 _(NO_TRANSLATION, "no translation")                     \
 199 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
 200 _(MAX_USER_SESS_EXCEEDED, "max user sessions exceeded") \
 201 _(DROP_FRAGMENT, "drop fragment")                       \
 202 _(CANNOT_CREATE_USER, "cannot create NAT user")         \
 203 _(NON_SYN, "non-SYN packet try to create session")      \
 204 _(TCP_PACKETS, "TCP packets")                           \
 205 _(TCP_CLOSED, "drops due to TCP in transitory timeout") \
 206 _(UDP_PACKETS, "UDP packets")                           \
 207 _(ICMP_PACKETS, "ICMP packets")                         \
 208 _(OTHER_PACKETS, "other protocol packets")              \
 209 _(FRAGMENTS, "fragments")                               \
 210 _(CACHED_FRAGMENTS, "cached fragments")                 \
 211 _(PROCESSED_FRAGMENTS, "processed fragments")
 212
 213 typedef enum
 214 {
 215 #define _(sym,str) NAT_OUT2IN_ED_ERROR_##sym,
 216   foreach_nat_out2in_ed_error
 217 #undef _
 218     NAT_OUT2IN_ED_N_ERROR,
 219 } nat_out2in_ed_error_t;
 220
 221
 222 /* Endpoint dependent TCP session state */
 223 #define NAT44_SES_I2O_FIN 1
 224 #define NAT44_SES_O2I_FIN 2
 225 #define NAT44_SES_I2O_FIN_ACK 4
 226 #define NAT44_SES_O2I_FIN_ACK 8
 227 #define NAT44_SES_I2O_SYN 16
 228 #define NAT44_SES_O2I_SYN 32
 229 #define NAT44_SES_RST     64
 230
 231 /* Session flags */
 232 #define SNAT_SESSION_FLAG_STATIC_MAPPING       1
 233 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO        2
 234 #define SNAT_SESSION_FLAG_LOAD_BALANCING       4
 235 #define SNAT_SESSION_FLAG_TWICE_NAT            8
 236 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT   16
 237 #define SNAT_SESSION_FLAG_FWD_BYPASS           32
 238 #define SNAT_SESSION_FLAG_AFFINITY             64
 239 #define SNAT_SESSION_FLAG_OUTPUT_FEATURE       128
 240
 241 /* NAT interface flags */
 242 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
 243 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
 244
 245 /* Static mapping flags */
 246 #define NAT_STATIC_MAPPING_FLAG_ADDR_ONLY    1
 247 #define NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY  2
 248 #define NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT 4
 249 #define NAT_STATIC_MAPPING_FLAG_LB           8
 250
 251 /* *INDENT-OFF* */
 252 typedef CLIB_PACKED(struct
 253 {
 254   /* Outside network key */
 255   snat_session_key_t out2in;
 256
 257   /* Inside network key */
 258   snat_session_key_t in2out;
 259
 260   /* Flags */
 261   u32 flags;
 262
 263   /* Per-user translations */
 264   u32 per_user_index;
 265   u32 per_user_list_head_index;
 266
 267   /* head of LRU list in which this session is tracked */
 268   u32 lru_head_index;
 269   /* index in global LRU list */
 270   u32 lru_index;
 271   f64 last_lru_update;
 272
 273   /* Last heard timer */
 274   f64 last_heard;
 275
 276   /* Last HA refresh */
 277   f64 ha_last_refreshed;
 278
 279   /* Counters */
 280   u64 total_bytes;
 281   u32 total_pkts;
 282
 283   /* External host address and port */
 284   ip4_address_t ext_host_addr;
 285   u16 ext_host_port;
 286
 287   /* External host address and port after translation */
 288   ip4_address_t ext_host_nat_addr;
 289   u16 ext_host_nat_port;
 290
 291   /* TCP session state */
 292   u8 state;
 293   u32 i2o_fin_seq;
 294   u32 o2i_fin_seq;
 295   u64 tcp_closed_timestamp;
 296
 297   /* user index */
 298   u32 user_index;
 299 }) snat_session_t;
 300 /* *INDENT-ON* */
 301
 302
 303 typedef struct
 304 {
 305   ip4_address_t addr;
 306   u32 fib_index;
 307   u32 sessions_per_user_list_head_index;
 308   u32 nsessions;
 309   u32 nstaticsessions;
 310 } snat_user_t;
 311
 312 typedef struct
 313 {
 314   ip4_address_t addr;
 315   u32 fib_index;
 316 /* *INDENT-OFF* */
 317 #define _(N, i, n, s) \
 318   u16 busy_##n##_ports; \
 319   u16 * busy_##n##_ports_per_thread; \
 320   u32 busy_##n##_port_refcounts[65535];
 321   foreach_nat_protocol
 322 #undef _
 323 /* *INDENT-ON* */
 324 } snat_address_t;
 325
 326 typedef struct
 327 {
 328   u32 fib_index;
 329   u32 refcount;
 330 } nat_outside_fib_t;
 331
 332 typedef struct
 333 {
 334   /* Inside network port */
 335   u16 in_port;
 336   /* Outside network address and port */
 337   snat_det_out_key_t out;
 338   /* Session state */
 339   u8 state;
 340   /* Expire timeout */
 341   u32 expire;
 342 } snat_det_session_t;
 343
 344 typedef struct
 345 {
 346   /* inside IP address range */
 347   ip4_address_t in_addr;
 348   u8 in_plen;
 349   /* outside IP address range */
 350   ip4_address_t out_addr;
 351   u8 out_plen;
 352   /* inside IP addresses / outside IP addresses */
 353   u32 sharing_ratio;
 354   /* number of ports available to internal host */
 355   u16 ports_per_host;
 356   /* session counter */
 357   u32 ses_num;
 358   /* vector of sessions */
 359   snat_det_session_t *sessions;
 360 } snat_det_map_t;
 361
 362 typedef struct
 363 {
 364   /* backend IP address */
 365   ip4_address_t addr;
 366   /* backend port number */
 367   u16 port;
 368   /* probability of the backend to be randomly matched */
 369   u8 probability;
 370   u8 prefix;
 371   /* backend FIB table */
 372   u32 vrf_id;
 373   u32 fib_index;
 374 } nat44_lb_addr_port_t;
 375
 376 typedef enum
 377 {
 378   /* twice-nat disabled */
 379   TWICE_NAT_DISABLED,
 380   /* twice-nat enabled */
 381   TWICE_NAT,
 382   /* twice-nat only when src IP equals dst IP after translation */
 383   TWICE_NAT_SELF,
 384 } twice_nat_type_t;
 385
 386 typedef enum
 387 {
 388   /* no load-balancing */
 389   NO_LB_NAT,
 390   /* load-balancing */
 391   LB_NAT,
 392   /* load-balancing with affinity */
 393   AFFINITY_LB_NAT,
 394 } lb_nat_type_t;
 395
 396 typedef struct
 397 {
 398   /* local IP address */
 399   ip4_address_t local_addr;
 400   /* external IP address */
 401   ip4_address_t external_addr;
 402   /* local port */
 403   u16 local_port;
 404   /* external port */
 405   u16 external_port;
 406   /* is twice-nat */
 407   twice_nat_type_t twice_nat;
 408   /* local FIB table */
 409   u32 vrf_id;
 410   u32 fib_index;
 411   /* protocol */
 412   nat_protocol_t proto;
 413   /* 0 = disabled, otherwise client IP affinity sticky time in seconds */
 414   u32 affinity;
 415   /* worker threads used by backends/local host */
 416   u32 *workers;
 417   /* opaque string tag */
 418   u8 *tag;
 419   /* backends for load-balancing mode */
 420   nat44_lb_addr_port_t *locals;
 421   /* affinity per service lis */
 422   u32 affinity_per_service_list_head_index;
 423   /* flags */
 424   u32 flags;
 425 } snat_static_mapping_t;
 426
 427 typedef struct
 428 {
 429   u32 sw_if_index;
 430   u8 flags;
 431 } snat_interface_t;
 432
 433 typedef struct
 434 {
 435   ip4_address_t l_addr;
 436   u16 l_port;
 437   u16 e_port;
 438   u32 sw_if_index;
 439   u32 vrf_id;
 440   nat_protocol_t proto;
 441   u32 flags;
 442   int addr_only;
 443   int twice_nat;
 444   int is_add;
 445   int out2in_only;
 446   int identity_nat;
 447   u8 *tag;
 448 } snat_static_map_resolve_t;
 449
 450 typedef struct
 451 {
 452   /* Main lookup tables */
 453   clib_bihash_8_8_t out2in;
 454   clib_bihash_8_8_t in2out;
 455
 456   /* Endpoint dependent sessions lookup tables */
 457   clib_bihash_16_8_t in2out_ed;
 458
 459   /* Find-a-user => src address lookup */
 460   clib_bihash_8_8_t user_hash;
 461
 462   /* User pool */
 463   snat_user_t *users;
 464
 465   /* Session pool */
 466   snat_session_t *sessions;
 467
 468   /* Pool of doubly-linked list elements */
 469   dlist_elt_t *list_pool;
 470
 471   /* LRU session list - head is stale, tail is fresh */
 472   dlist_elt_t *lru_pool;
 473   u32 tcp_trans_lru_head_index;
 474   u32 tcp_estab_lru_head_index;
 475   u32 udp_lru_head_index;
 476   u32 icmp_lru_head_index;
 477   u32 unk_proto_lru_head_index;
 478
 479   /* NAT thread index */
 480   u32 snat_thread_index;
 481
 482   /* real thread index */
 483   u32 thread_index;
 484
 485 } snat_main_per_thread_data_t;
 486
 487 struct snat_main_s;
 488
 489 /* ICMP session match function */
 490 typedef u32 (snat_icmp_match_function_t) (struct snat_main_s * sm,
 491                                           vlib_node_runtime_t * node,
 492                                           u32 thread_index,
 493                                           vlib_buffer_t * b0,
 494                                           ip4_header_t * ip0, u8 * p_proto,
 495                                           snat_session_key_t * p_value,
 496                                           u8 * p_dont_translate, void *d,
 497                                           void *e);
 498
 499 /* Return worker thread index for given packet */
 500 typedef u32 (snat_get_worker_in2out_function_t) (ip4_header_t * ip,
 501                                                  u32 rx_fib_index,
 502                                                  u8 is_output);
 503
 504 typedef u32 (snat_get_worker_out2in_function_t) (vlib_buffer_t * b,
 505                                                  ip4_header_t * ip,
 506                                                  u32 rx_fib_index,
 507                                                  u8 is_output);
 508
 509 /* NAT address and port allocation function */
 510 typedef int (nat_alloc_out_addr_and_port_function_t) (snat_address_t *
 511                                                       addresses,
 512                                                       u32 fib_index,
 513                                                       u32 thread_index,
 514                                                       snat_session_key_t * k,
 515                                                       u16 port_per_thread,
 516                                                       u32 snat_thread_index);
 517
 518
 519 typedef struct snat_main_s
 520 {
 521   /* ICMP session match functions */
 522   snat_icmp_match_function_t *icmp_match_in2out_cb;
 523   snat_icmp_match_function_t *icmp_match_out2in_cb;
 524
 525   /* Thread settings */
 526   u32 num_workers;
 527   u32 first_worker_index;
 528   u32 *workers;
 529   snat_get_worker_in2out_function_t *worker_in2out_cb;
 530   snat_get_worker_out2in_function_t *worker_out2in_cb;
 531   u16 port_per_thread;
 532
 533   /* Per thread data */
 534   snat_main_per_thread_data_t *per_thread_data;
 535
 536   /* Find a static mapping by local */
 537   clib_bihash_8_8_t static_mapping_by_local;
 538
 539   /* Find a static mapping by external */
 540   clib_bihash_8_8_t static_mapping_by_external;
 541
 542   /* Static mapping pool */
 543   snat_static_mapping_t *static_mappings;
 544
 545   /* Endpoint-dependent out2in mappings */
 546   clib_bihash_16_8_t out2in_ed;
 547
 548   /* Interface pool */
 549   snat_interface_t *interfaces;
 550   snat_interface_t *output_feature_interfaces;
 551
 552   /* Vector of outside addresses */
 553   snat_address_t *addresses;
 554   /* Address and port allocation function */
 555   nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
 556   /* Address and port allocation type */
 557   nat_addr_and_port_alloc_alg_t addr_and_port_alloc_alg;
 558   /* Port set parameters (MAP-E) */
 559   u8 psid_offset;
 560   u8 psid_length;
 561   u16 psid;
 562   /* Port range parameters */
 563   u16 start_port;
 564   u16 end_port;
 565
 566   /* vector of outside fibs */
 567   nat_outside_fib_t *outside_fibs;
 568
 569   /* Vector of twice NAT addresses for external hosts */
 570   snat_address_t *twice_nat_addresses;
 571
 572   /* sw_if_indices whose intfc addresses should be auto-added */
 573   u32 *auto_add_sw_if_indices;
 574   u32 *auto_add_sw_if_indices_twice_nat;
 575
 576   /* vector of interface address static mappings to resolve. */
 577   snat_static_map_resolve_t *to_resolve;
 578
 579   /* Randomize port allocation order */
 580   u32 random_seed;
 581
 582   /* Worker handoff frame-queue index */
 583   u32 fq_in2out_index;
 584   u32 fq_in2out_output_index;
 585   u32 fq_out2in_index;
 586
 587   /* node indexes */
 588   u32 error_node_index;
 589
 590   /* handoff fq nodes  */
 591   u32 handoff_out2in_index;
 592   u32 handoff_in2out_index;
 593   u32 handoff_in2out_output_index;
 594
 595   /* respect feature arc nodes */
 596   u32 pre_out2in_node_index;
 597   u32 pre_in2out_node_index;
 598
 599   u32 in2out_node_index;
 600   u32 in2out_output_node_index;
 601   u32 in2out_fast_node_index;
 602   u32 in2out_slowpath_node_index;
 603   u32 in2out_slowpath_output_node_index;
 604   u32 ed_in2out_node_index;
 605   u32 ed_in2out_slowpath_node_index;
 606   u32 out2in_node_index;
 607   u32 out2in_fast_node_index;
 608   u32 ed_out2in_node_index;
 609   u32 ed_out2in_slowpath_node_index;
 610   u32 det_in2out_node_index;
 611   u32 det_out2in_node_index;
 612
 613   u32 hairpinning_node_index;
 614   u32 hairpin_dst_node_index;
 615   u32 hairpin_src_node_index;
 616   u32 ed_hairpinning_node_index;
 617   u32 ed_hairpin_dst_node_index;
 618   u32 ed_hairpin_src_node_index;
 619
 620
 621   /* Deterministic NAT mappings */
 622   snat_det_map_t *det_maps;
 623
 624   /* If forwarding is enabled */
 625   u8 forwarding_enabled;
 626
 627   /* Config parameters */
 628   u8 static_mapping_only;
 629   u8 static_mapping_connection_tracking;
 630   u8 deterministic;
 631   u8 out2in_dpo;
 632   u8 endpoint_dependent;
 633
 634   u32 translation_buckets;
 635   uword translation_memory_size;
 636   u32 max_translations;
 637   u32 *max_translations_per_fib;
 638
 639   u32 user_buckets;
 640   uword user_memory_size;
 641   u32 max_translations_per_user;
 642
 643   u32 outside_vrf_id;
 644   u32 outside_fib_index;
 645   u32 inside_vrf_id;
 646   u32 inside_fib_index;
 647
 648   /* values of various timeouts */
 649   // proto timeouts
 650   u32 udp_timeout;
 651   u32 tcp_transitory_timeout;
 652   u32 tcp_established_timeout;
 653   u32 icmp_timeout;
 654
 655   /* TCP MSS clamping */
 656   u16 mss_clamping;
 657
 658   /* counters/gauges */
 659   vlib_simple_counter_main_t total_users;
 660   vlib_simple_counter_main_t total_sessions;
 661
 662   /* API message ID base */
 663   u16 msg_id_base;
 664
 665   /* log class */
 666   vlib_log_class_t log_class;
 667   /* logging level */
 668   u8 log_level;
 669
 670   /* convenience */
 671   vnet_main_t *vnet_main;
 672   ip4_main_t *ip4_main;
 673   ip_lookup_main_t *ip4_lookup_main;
 674   api_main_t *api_main;
 675 } snat_main_t;
 676
 677 typedef struct
 678 {
 679   u32 thread_index;
 680   f64 now;
 681 } nat44_is_idle_session_ctx_t;
 682
 683 typedef struct
 684 {
 685   u32 cached_sw_if_index;
 686   u32 cached_ip4_address;
 687 } snat_runtime_t;
 688
 689 extern snat_main_t snat_main;
 690
 691 // nat pre ed next_node feature classification
 692 extern vlib_node_registration_t nat_default_node;
 693 extern vlib_node_registration_t nat_pre_in2out_node;
 694 extern vlib_node_registration_t nat_pre_out2in_node;
 695
 696 extern vlib_node_registration_t snat_in2out_node;
 697 extern vlib_node_registration_t snat_in2out_output_node;
 698 extern vlib_node_registration_t snat_out2in_node;
 699 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
 700 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
 701 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
 702 extern vlib_node_registration_t snat_det_in2out_node;
 703 extern vlib_node_registration_t snat_det_out2in_node;
 704 extern vlib_node_registration_t nat44_ed_in2out_node;
 705 extern vlib_node_registration_t nat44_ed_in2out_output_node;
 706 extern vlib_node_registration_t nat44_ed_out2in_node;
 707
 708 extern fib_source_t nat_fib_src_hi;
 709 extern fib_source_t nat_fib_src_low;
 710
 711 /* format functions */
 712 format_function_t format_snat_user;
 713 format_function_t format_snat_static_mapping;
 714 format_function_t format_snat_static_map_to_resolve;
 715 format_function_t format_snat_session;
 716 format_function_t format_det_map_ses;
 717 format_function_t format_snat_key;
 718 format_function_t format_static_mapping_key;
 719 format_function_t format_nat_protocol;
 720 format_function_t format_nat_addr_and_port_alloc_alg;
 721 /* unformat functions */
 722 unformat_function_t unformat_nat_protocol;
 723
 724 /** \brief Check if SNAT session is created from static mapping.
 725     @param s SNAT session
 726     @return 1 if SNAT session is created from static mapping otherwise 0
 727 */
 728 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
 729
 730 /** \brief Check if SNAT session for unknown protocol.
 731     @param s SNAT session
 732     @return 1 if SNAT session for unknown protocol otherwise 0
 733 */
 734 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
 735
 736 /** \brief Check if NAT session is twice NAT.
 737     @param s NAT session
 738     @return 1 if NAT session is twice NAT
 739 */
 740 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
 741
 742 /** \brief Check if NAT session is load-balancing.
 743     @param s NAT session
 744     @return 1 if NAT session is load-balancing
 745 */
 746 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
 747
 748 /** \brief Check if NAT session is forwarding bypass.
 749     @param s NAT session
 750     @return 1 if NAT session is load-balancing
 751 */
 752 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
 753
 754 /** \brief Check if NAT session is endpoint dependent.
 755     @param s NAT session
 756     @return 1 if NAT session is endpoint dependent
 757 */
 758 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
 759
 760 /** \brief Check if NAT session has affinity record.
 761     @param s NAT session
 762     @return 1 if NAT session has affinity record
 763 */
 764 #define is_affinity_sessions(s) (s->flags & SNAT_SESSION_FLAG_AFFINITY)
 765
 766 /** \brief Check if NAT interface is inside.
 767     @param i NAT interface
 768     @return 1 if inside interface
 769 */
 770 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
 771
 772 /** \brief Check if NAT interface is outside.
 773     @param i NAT interface
 774     @return 1 if outside interface
 775 */
 776 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
 777
 778 /** \brief Check if NAT44 endpoint-dependent TCP session is closed.
 779     @param s NAT session
 780     @return 1 if session is closed
 781 */
 782 #define nat44_is_ses_closed(s) s->state == 0xf
 783
 784 /** \brief Check if NAT static mapping is address only (1:1NAT).
 785     @param sm NAT static mapping
 786     @return 1 if 1:1NAT, 0 if 1:1NAPT
 787 */
 788 #define is_addr_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_ADDR_ONLY)
 789
 790 /** \brief Check if NAT static mapping match only out2in direction.
 791     @param sm NAT static mapping
 792     @return 1 if rule match only out2in direction
 793 */
 794 #define is_out2in_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY)
 795
 796 /** \brief Check if NAT static mapping is identity NAT.
 797     @param sm NAT static mapping
 798     @return 1 if identity NAT
 799 */
 800 #define is_identity_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT)
 801
 802 /** \brief Check if NAT static mapping is load-balancing.
 803     @param sm NAT static mapping
 804     @return 1 if load-balancing
 805 */
 806 #define is_lb_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_LB)
 807
 808 /** \brief Check if client initiating TCP connection (received SYN from client)
 809     @param t TCP header
 810     @return 1 if client initiating TCP connection
 811 */
 812 always_inline bool
 813 tcp_flags_is_init (u8 f)
 814 {
 815   return (f & TCP_FLAG_SYN) && !(f & TCP_FLAG_ACK);
 816 }
 817
 818 /* logging */
 819 #define nat_log_err(...) \
 820   vlib_log(VLIB_LOG_LEVEL_ERR, snat_main.log_class, __VA_ARGS__)
 821 #define nat_log_warn(...) \
 822   vlib_log(VLIB_LOG_LEVEL_WARNING, snat_main.log_class, __VA_ARGS__)
 823 #define nat_log_notice(...) \
 824   vlib_log(VLIB_LOG_LEVEL_NOTICE, snat_main.log_class, __VA_ARGS__)
 825 #define nat_log_info(...) \
 826   vlib_log(VLIB_LOG_LEVEL_INFO, snat_main.log_class, __VA_ARGS__)
 827 #define nat_log_debug(...)\
 828   vlib_log(VLIB_LOG_LEVEL_DEBUG, snat_main.log_class, __VA_ARGS__)
 829
 830 /* NAT API Logging Levels */
 831 #define foreach_nat_log_level \
 832   _(0x00, LOG_NONE)           \
 833   _(0x01, LOG_ERROR)          \
 834   _(0x02, LOG_WARNING)        \
 835   _(0x03, LOG_NOTICE)         \
 836   _(0x04, LOG_INFO)           \
 837   _(0x05, LOG_DEBUG)
 838
 839 typedef enum nat_log_level_t_
 840 {
 841 #define _(n,f) SNAT_##f = n,
 842   foreach_nat_log_level
 843 #undef _
 844 } nat_log_level_t;
 845
 846 #define nat_elog(_level, _str)                           \
 847 do                                                       \
 848   {                                                      \
 849     snat_main_t *sm = &snat_main;                        \
 850     if (PREDICT_FALSE (sm->log_level >= _level))         \
 851       {                                                  \
 852         ELOG_TYPE_DECLARE (e) =                          \
 853           {                                              \
 854             .format = "nat-msg " _str,                   \
 855             .format_args = "",                           \
 856           };                                             \
 857         ELOG_DATA (&vlib_global_main.elog_main, e);      \
 858       }                                                  \
 859   } while (0);
 860
 861 #define nat_elog_addr(_level, _str, _addr)               \
 862 do                                                       \
 863   {                                                      \
 864     if (PREDICT_FALSE (sm->log_level >= _level))         \
 865       {                                                  \
 866         ELOG_TYPE_DECLARE (e) =                          \
 867           {                                              \
 868             .format = "nat-msg " _str " %d.%d.%d.%d",    \
 869             .format_args = "i1i1i1i1",                   \
 870           };                                             \
 871         CLIB_PACKED(struct                               \
 872           {                                              \
 873             u8 oct1;                                     \
 874             u8 oct2;                                     \
 875             u8 oct3;                                     \
 876             u8 oct4;                                     \
 877           }) *ed;                                        \
 878         ed = ELOG_DATA (&vlib_global_main.elog_main, e); \
 879         ed->oct4 = _addr >> 24;                          \
 880         ed->oct3 = _addr >> 16;                          \
 881         ed->oct2 = _addr >> 8;                           \
 882         ed->oct1 = _addr;                                \
 883     }                                                    \
 884   } while (0);
 885
 886 #define nat_elog_debug_handoff(_str, _tid, _fib, _src, _dst)                \
 887 do                                                                          \
 888   {                                                                         \
 889   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                      \
 890     {                                                                       \
 891       ELOG_TYPE_DECLARE (e) =                                               \
 892         {                                                                   \
 893           .format = "nat-msg " _str " ip src: %d.%d.%d.%d dst: %d.%d.%d.%d" \
 894                                     " tid from: %d to: %d fib: %d",         \
 895         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                            \
 896       };                                                                    \
 897       CLIB_PACKED(struct                                                    \
 898         {                                                                   \
 899           u8 src_oct1;                                                      \
 900           u8 src_oct2;                                                      \
 901           u8 src_oct3;                                                      \
 902           u8 src_oct4;                                                      \
 903           u8 dst_oct1;                                                      \
 904           u8 dst_oct2;                                                      \
 905           u8 dst_oct3;                                                      \
 906           u8 dst_oct4;                                                      \
 907           u32 ftid;                                                         \
 908           u32 ttid;                                                         \
 909           u32 fib;                                                          \
 910         }) *ed;                                                             \
 911       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                      \
 912       ed->src_oct1 = _src >> 24;                                            \
 913       ed->src_oct2 = _src >> 16;                                            \
 914       ed->src_oct3 = _src >> 8;                                             \
 915       ed->src_oct4 = _src;                                                  \
 916       ed->dst_oct1 = _dst >> 24;                                            \
 917       ed->dst_oct2 = _dst >> 16;                                            \
 918       ed->dst_oct3 = _dst >> 8;                                             \
 919       ed->dst_oct4 = _dst;                                                  \
 920       ed->ftid = vlib_get_thread_index ();                                  \
 921       ed->ttid = _tid;                                                      \
 922       ed->fib = _fib;                                                       \
 923     }                                                                       \
 924   } while (0);
 925
 926 #define nat_elog_debug_handoff_v2(_str, _prt, _fib, _src, _dst)              \
 927 do                                                                           \
 928   {                                                                          \
 929   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                       \
 930     {                                                                        \
 931       ELOG_TYPE_DECLARE (e) =                                                \
 932         {                                                                    \
 933           .format = "nat-msg " _str " ip_src:%d.%d.%d.%d ip_dst:%d.%d.%d.%d" \
 934                                     " tid:%d prt:%d fib:%d",                 \
 935         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                             \
 936       };                                                                     \
 937       CLIB_PACKED(struct                                                     \
 938         {                                                                    \
 939           u8 src_oct1;                                                       \
 940           u8 src_oct2;                                                       \
 941           u8 src_oct3;                                                       \
 942           u8 src_oct4;                                                       \
 943           u8 dst_oct1;                                                       \
 944           u8 dst_oct2;                                                       \
 945           u8 dst_oct3;                                                       \
 946           u8 dst_oct4;                                                       \
 947           u32 tid;                                                           \
 948           u32 prt;                                                           \
 949           u32 fib;                                                           \
 950         }) *ed;                                                              \
 951       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                       \
 952       ed->src_oct1 = _src >> 24;                                             \
 953       ed->src_oct2 = _src >> 16;                                             \
 954       ed->src_oct3 = _src >> 8;                                              \
 955       ed->src_oct4 = _src;                                                   \
 956       ed->dst_oct1 = _dst >> 24;                                             \
 957       ed->dst_oct2 = _dst >> 16;                                             \
 958       ed->dst_oct3 = _dst >> 8;                                              \
 959       ed->dst_oct4 = _dst;                                                   \
 960       ed->tid = vlib_get_thread_index ();                                    \
 961       ed->prt = _prt;                                                        \
 962       ed->fib = _fib;                                                        \
 963     }                                                                        \
 964   } while (0);
 965
 966 #define nat_elog_X1(_level, _fmt, _arg, _val1)            \
 967 do                                                        \
 968   {                                                       \
 969     snat_main_t *sm = &snat_main;                         \
 970     if (PREDICT_FALSE (sm->log_level >= _level))          \
 971       {                                                   \
 972         ELOG_TYPE_DECLARE (e) =                           \
 973           {                                               \
 974             .format = "nat-msg " _fmt,                    \
 975             .format_args = _arg,                          \
 976           };                                              \
 977         CLIB_PACKED(struct                                \
 978           {                                               \
 979             typeof (_val1) val1;                          \
 980           }) *ed;                                         \
 981         ed = ELOG_DATA (&vlib_global_main.elog_main, e);  \
 982         ed->val1 = _val1;                                 \
 983       }                                                   \
 984   } while (0);
 985
 986 #define nat_elog_notice(nat_elog_str) \
 987   nat_elog(SNAT_LOG_INFO, "[notice] " nat_elog_str)
 988 #define nat_elog_warn(nat_elog_str) \
 989   nat_elog(SNAT_LOG_WARNING, "[warning] " nat_elog_str)
 990 #define nat_elog_err(nat_elog_str) \
 991   nat_elog(SNAT_LOG_ERROR, "[error] " nat_elog_str)
 992 #define nat_elog_debug(nat_elog_str) \
 993   nat_elog(SNAT_LOG_DEBUG, "[debug] " nat_elog_str)
 994 #define nat_elog_info(nat_elog_str) \
 995   nat_elog(SNAT_LOG_INFO, "[info] " nat_elog_str)
 996
 997 #define nat_elog_notice_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
 998   nat_elog_X1(SNAT_LOG_NOTICE, "[notice] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
 999 #define nat_elog_warn_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1000   nat_elog_X1(SNAT_LOG_WARNING, "[warning] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1001 #define nat_elog_err_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1002   nat_elog_X1(SNAT_LOG_ERROR, "[error] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1003 #define nat_elog_debug_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1004   nat_elog_X1(SNAT_LOG_DEBUG, "[debug] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1005 #define nat_elog_info_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1006   nat_elog_X1(SNAT_LOG_INFO, "[info] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1007
1008 /* ICMP session match functions */
1009 u32 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1010                             u32 thread_index, vlib_buffer_t * b0,
1011                             ip4_header_t * ip0, u8 * p_proto,
1012                             snat_session_key_t * p_value,
1013                             u8 * p_dont_translate, void *d, void *e);
1014 u32 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1015                             u32 thread_index, vlib_buffer_t * b0,
1016                             ip4_header_t * ip0, u8 * p_proto,
1017                             snat_session_key_t * p_value,
1018                             u8 * p_dont_translate, void *d, void *e);
1019 u32 icmp_match_out2in_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1020                             u32 thread_index, vlib_buffer_t * b0,
1021                             ip4_header_t * ip0, u8 * p_proto,
1022                             snat_session_key_t * p_value,
1023                             u8 * p_dont_translate, void *d, void *e);
1024 u32 icmp_match_out2in_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1025                             u32 thread_index, vlib_buffer_t * b0,
1026                             ip4_header_t * ip0, u8 * p_proto,
1027                             snat_session_key_t * p_value,
1028                             u8 * p_dont_translate, void *d, void *e);
1029
1030 /* ICMP deterministic NAT session match functions */
1031 u32 icmp_match_out2in_det (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 u32 icmp_match_in2out_det (snat_main_t * sm, vlib_node_runtime_t * node,
1037                            u32 thread_index, vlib_buffer_t * b0,
1038                            ip4_header_t * ip0, u8 * p_proto,
1039                            snat_session_key_t * p_value,
1040                            u8 * p_dont_translate, void *d, void *e);
1041
1042 /* ICMP endpoint-dependent session match functions */
1043 u32 icmp_match_out2in_ed (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 u32 icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
1049                           u32 thread_index, vlib_buffer_t * b0,
1050                           ip4_header_t * ip0, u8 * p_proto,
1051                           snat_session_key_t * p_value,
1052                           u8 * p_dont_translate, void *d, void *e);
1053
1054 u32 icmp_in2out (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1055                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1056                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1057                  void *d, void *e);
1058
1059 u32 icmp_out2in (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1060                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1061                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1062                  void *d, void *e);
1063
1064 /* hairpinning functions */
1065 u32 snat_icmp_hairpinning (snat_main_t * sm, vlib_buffer_t * b0,
1066                            ip4_header_t * ip0, icmp46_header_t * icmp0,
1067                            int is_ed);
1068 void nat_hairpinning_sm_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1069                                        ip4_header_t * ip);
1070 void nat44_ed_hairpinning_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1071                                          ip4_header_t * ip);
1072 int snat_hairpinning (snat_main_t * sm, vlib_buffer_t * b0,
1073                       ip4_header_t * ip0, udp_header_t * udp0,
1074                       tcp_header_t * tcp0, u32 proto0, int is_ed);
1075
1076 /* Call back functions for clib_bihash_add_or_overwrite_stale */
1077 int nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1078 int nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg);
1079 int nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1080 int nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1081
1082 /**
1083  * @brief Add external address to NAT44 pool
1084  *
1085  * @param sm        snat global configuration data
1086  * @param addr      IPv4 address
1087  * @param vrf_id    VRF id of tenant, ~0 means independent of VRF
1088  * @param twice_nat 1 if twice NAT address
1089  *
1090  * @return 0 on success, non-zero value otherwise
1091  */
1092 int snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
1093                       u8 twice_nat);
1094
1095 /**
1096  * @brief Delete external address from NAT44 pool
1097  *
1098  * @param sm        snat global configuration data
1099  * @param addr      IPv4 address
1100  * @param delete_sm 1 if delete static mapping using address
1101  * @param twice_nat 1 if twice NAT address
1102  *
1103  * @return 0 on success, non-zero value otherwise
1104  */
1105 int snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
1106                       u8 twice_nat);
1107
1108 /**
1109  * @brief Add/delete external address to FIB DPO (out2in DPO mode)
1110  *
1111  * @param addr   IPv4 address
1112  * @param is_add 1 = add, 0 = delete
1113  *
1114  * @return 0 on success, non-zero value otherwise
1115  */
1116 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
1117
1118 /**
1119  * @brief Add/delete NAT44 static mapping
1120  *
1121  * @param l_addr       local IPv4 address
1122  * @param e_addr       external IPv4 address
1123  * @param l_port       local port number
1124  * @param e_port       external port number
1125  * @param vrf_id       local VRF ID
1126  * @param addr_only    1 = 1:1NAT, 0 = 1:1NAPT
1127  * @param sw_if_index  use interface address as external IPv4 address
1128  * @param proto        L4 protocol
1129  * @param is_add       1 = add, 0 = delete
1130  * @param twice_nat    twice-nat mode
1131  * @param out2in_only  if 1 rule match only out2in direction
1132  * @param tag          opaque string tag
1133  * @param identity_nat identity NAT
1134  *
1135  * @return 0 on success, non-zero value otherwise
1136  */
1137 int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
1138                              u16 l_port, u16 e_port, u32 vrf_id,
1139                              int addr_only, u32 sw_if_index,
1140                              nat_protocol_t proto, int is_add,
1141                              twice_nat_type_t twice_nat, u8 out2in_only,
1142                              u8 * tag, u8 identity_nat);
1143
1144 /**
1145  * @brief Add/delete static mapping with load-balancing (multiple backends)
1146  *
1147  * @param e_addr      external IPv4 address
1148  * @param e_port      external port number
1149  * @param proto       L4 protocol
1150  * @param locals      list of local backends
1151  * @param is_add      1 = add, 0 = delete
1152  * @param twice_nat   twice-nat mode
1153  * @param out2in_only if 1 rule match only out2in direction
1154  * @param tag         opaque string tag
1155  * @param affinity    0 = disabled, otherwise client IP affinity sticky time
1156  *
1157  * @return 0 on success, non-zero value otherwise
1158  */
1159 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
1160                                      nat_protocol_t proto,
1161                                      nat44_lb_addr_port_t * locals, u8 is_add,
1162                                      twice_nat_type_t twice_nat,
1163                                      u8 out2in_only, u8 * tag, u32 affinity);
1164
1165 int nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
1166                                            ip4_address_t l_addr, u16 l_port,
1167                                            nat_protocol_t proto, u32 vrf_id,
1168                                            u8 probability, u8 is_add);
1169
1170 clib_error_t *snat_api_init (vlib_main_t * vm, snat_main_t * sm);
1171
1172 /**
1173  * @brief Set NAT plugin workers
1174  *
1175  * @param bitmap NAT workers bitmap
1176  *
1177  * @return 0 on success, non-zero value otherwise
1178  */
1179 int snat_set_workers (uword * bitmap);
1180
1181 /**
1182  * @brief Enable/disable NAT44 feature on the interface
1183  *
1184  * @param sw_if_index software index of the interface
1185  * @param is_inside   1 = inside, 0 = outside
1186  * @param is_del      1 = delete, 0 = add
1187  *
1188  * @return 0 on success, non-zero value otherwise
1189  */
1190 int snat_interface_add_del (u32 sw_if_index, u8 is_inside, int is_del);
1191
1192 /**
1193  * @brief Enable/disable NAT44 output feature on the interface (postrouting NAT)
1194  *
1195  * @param sw_if_index software index of the interface
1196  * @param is_inside   1 = inside, 0 = outside
1197  * @param is_del      1 = delete, 0 = add
1198  *
1199  * @return 0 on success, non-zero value otherwise
1200  */
1201 int snat_interface_add_del_output_feature (u32 sw_if_index, u8 is_inside,
1202                                            int is_del);
1203
1204 /**
1205  * @brief Add/delete NAT44 pool address from specific interface
1206  *
1207  * @param sw_if_index software index of the interface
1208  * @param is_del      1 = delete, 0 = add
1209  * @param twice_nat   1 = twice NAT address for external hosts
1210  *
1211  * @return 0 on success, non-zero value otherwise
1212  */
1213 int snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
1214                                 u8 twice_nat);
1215
1216 /**
1217  * @brief Delete NAT44 session
1218  *
1219  * @param addr   IPv4 address
1220  * @param port   L4 port number
1221  * @param proto  L4 protocol
1222  * @param vrf_id VRF ID
1223  * @param is_in  1 = inside network address and port pair, 0 = outside
1224  *
1225  * @return 0 on success, non-zero value otherwise
1226  */
1227 int nat44_del_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1228                        nat_protocol_t proto, u32 vrf_id, int is_in);
1229
1230 /**
1231  * @brief Delete NAT44 endpoint-dependent session
1232  *
1233  * @param sm     snat global configuration data
1234  * @param addr   IPv4 address
1235  * @param port   L4 port number
1236  * @param proto  L4 protocol
1237  * @param vrf_id VRF ID
1238  * @param is_in  1 = inside network address and port pair, 0 = outside
1239  *
1240  * @return 0 on success, non-zero value otherwise
1241  */
1242 int nat44_del_ed_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1243                           ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1244                           u32 vrf_id, int is_in);
1245
1246 /**
1247  * @brief Free NAT44 session data (lookup keys, external address port)
1248  *
1249  * @param sm           snat global configuration data
1250  * @param s            NAT session
1251  * @param thread_index thread index
1252  * @param is_ha        is HA event
1253  */
1254 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
1255                             u32 thread_index, u8 is_ha);
1256
1257 /**
1258  * @brief Set NAT44 session limit (session limit, vrf id)
1259  *
1260  * @param session_limit Session limit
1261  * @param vrf_id        VRF id
1262  * @return 0 on success, non-zero value otherwise
1263  */
1264 int nat44_set_session_limit (u32 session_limit, u32 vrf_id);
1265
1266 /**
1267  * @brief Free NAT44 ED session data (lookup keys, external address port)
1268  *
1269  * @param s            NAT session
1270  * @param thread_index thread index
1271  * @param is_ha        is HA event
1272  */
1273 void
1274 nat44_free_session_data (snat_main_t * sm, snat_session_t * s,
1275                          u32 thread_index, u8 is_ha);
1276
1277 /**
1278  * @brief Initialize NAT44 data
1279  *
1280  * @param tsm          per thread data
1281  */
1282 void nat44_db_init (snat_main_per_thread_data_t * tsm);
1283
1284 /**
1285  * @brief Free NAT44 data
1286  *
1287  * @param tsm          per thread data
1288  */
1289 void nat44_db_free (snat_main_per_thread_data_t * tsm);
1290
1291 void nat44_sessions_clear ();
1292
1293 /**
1294  * @brief Find or create NAT user
1295  *
1296  * @param sm           snat global configuration data
1297  * @param addr         IPv4 address
1298  * @param fib_index    FIB table index
1299  * @param thread_index thread index
1300  *
1301  * @return NAT user data structure on success otherwise zero value
1302  */
1303 snat_user_t *nat_user_get_or_create (snat_main_t * sm,
1304                                      ip4_address_t * addr, u32 fib_index,
1305                                      u32 thread_index);
1306
1307 /**
1308  * @brief Allocate new NAT session or recycle last used
1309  *
1310  * @param sm           snat global configuration data
1311  * @param u            NAT user
1312  * @param thread_index thread index
1313  * @param now          time now
1314  *
1315  * @return session data structure on success otherwise zero value
1316  */
1317 snat_session_t *nat_session_alloc_or_recycle (snat_main_t * sm,
1318                                               snat_user_t * u,
1319                                               u32 thread_index, f64 now);
1320
1321 /**
1322  * @brief Set address and port assignment algorithm for MAP-E CE
1323  *
1324  * @param psid        Port Set Identifier value
1325  * @param psid_offset number of offset bits
1326  * @param psid_length length of PSID
1327  */
1328 void nat_set_alloc_addr_and_port_mape (u16 psid, u16 psid_offset,
1329                                        u16 psid_length);
1330
1331 /**
1332  * @brief Set address and port assignment algorithm for port range
1333  *
1334  * @param start_port beginning of the port range
1335  * @param end_port   end of the port range
1336  */
1337 void nat_set_alloc_addr_and_port_range (u16 start_port, u16 end_port);
1338
1339 /**
1340  * @brief Set address and port assignment algorithm to default/standard
1341  */
1342 void nat_set_alloc_addr_and_port_default (void);
1343
1344 /**
1345  * @brief Free outside address and port pair
1346  *
1347  * @param addresses    vector of outside addresses
1348  * @param thread_index thread index
1349  * @param k            address, port and protocol
1350  */
1351 void snat_free_outside_address_and_port (snat_address_t * addresses,
1352                                          u32 thread_index,
1353                                          snat_session_key_t * k);
1354
1355 /**
1356  * @brief Alloc outside address and port
1357  *
1358  * @param addresses         vector of outside addresses
1359  * @param fib_index         FIB table index
1360  * @param thread_index      thread index
1361  * @param k                 allocated address and port pair
1362  * @param port_per_thread   number of ports per thread
1363  * @param snat_thread_index NAT thread index
1364  *
1365  * @return 0 on success, non-zero value otherwise
1366  */
1367 int snat_alloc_outside_address_and_port (snat_address_t * addresses,
1368                                          u32 fib_index,
1369                                          u32 thread_index,
1370                                          snat_session_key_t * k,
1371                                          u16 port_per_thread,
1372                                          u32 snat_thread_index);
1373
1374 /**
1375  * @brief Match NAT44 static mapping.
1376  *
1377  * @param match         address and port to match
1378  * @param mapping       external/local address and port of the matched mapping
1379  * @param by_external   if 0 match by local address otherwise match by external
1380  *                      address
1381  * @param is_addr_only  1 if matched mapping is address only
1382  * @param twice_nat     matched mapping is twice NAT type
1383  * @param lb            1 if matched mapping is load-balanced
1384  * @param ext_host_addr external host address
1385  *
1386  * @returns 0 if match found otherwise 1.
1387  */
1388 int snat_static_mapping_match (snat_main_t * sm,
1389                                snat_session_key_t match,
1390                                snat_session_key_t * mapping,
1391                                u8 by_external,
1392                                u8 * is_addr_only,
1393                                twice_nat_type_t * twice_nat,
1394                                lb_nat_type_t * lb,
1395                                ip4_address_t * ext_host_addr,
1396                                u8 * is_identity_nat);
1397
1398 /**
1399  * @brief Add/del NAT address to FIB.
1400  *
1401  * Add the external NAT address to the FIB as receive entries. This ensures
1402  * that VPP will reply to ARP for this address and we don't need to enable
1403  * proxy ARP on the outside interface.
1404  *
1405  * @param addr        IPv4 address
1406  * @param plen        address prefix length
1407  * @param sw_if_index software index of the outside interface
1408  * @param is_add      0 = delete, 1 = add.
1409  */
1410 void snat_add_del_addr_to_fib (ip4_address_t * addr,
1411                                u8 p_len, u32 sw_if_index, int is_add);
1412
1413 /*
1414  * Why is this here? Because we don't need to touch this layer to
1415  * simply reply to an icmp. We need to change id to a unique
1416  * value to NAT an echo request/reply.
1417  */
1418
1419 typedef struct
1420 {
1421   u16 identifier;
1422   u16 sequence;
1423 } icmp_echo_header_t;
1424
1425 typedef struct
1426 {
1427   u16 src_port, dst_port;
1428 } tcp_udp_header_t;
1429
1430 u8 *format_user_kvp (u8 * s, va_list * args);
1431 #endif /* __included_nat_h__ */
1432 /*
1433  * fd.io coding-style-patch-verification: ON
1434  *
1435  * Local Variables:
1436  * eval: (c-set-style "gnu")
1437  * End:
1438  */