nat: deal with flows instead of sessions
[vpp.git] / src / plugins / nat / nat.h
1 /*
2  * Copyright (c) 2020 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 /* number of worker handoff frame queue elements */
40 #define NAT_FQ_NELTS 64
41
42 /* NAT buffer flags */
43 #define SNAT_FLAG_HAIRPINNING (1 << 0)
44
45 /* NAT44 API Configuration flags */
46 #define foreach_nat44_config_flag  \
47   _(0x00, IS_ENDPOINT_INDEPENDENT) \
48   _(0x01, IS_ENDPOINT_DEPENDENT)   \
49   _(0x02, IS_STATIC_MAPPING_ONLY)  \
50   _(0x04, IS_CONNECTION_TRACKING)  \
51   _(0x08, IS_OUT2IN_DPO)
52
53 typedef enum nat44_config_flags_t_
54 {
55 #define _(n,f) NAT44_API_##f = n,
56   foreach_nat44_config_flag
57 #undef _
58 } nat44_config_flags_t;
59
60 typedef struct
61 {
62   /* nat44 plugin features */
63   u8 static_mapping_only;
64   u8 connection_tracking;
65   u8 endpoint_dependent;
66   u8 out2in_dpo;
67
68   u32 inside_vrf;
69   u32 outside_vrf;
70
71   /* maximum number of users */
72   u32 users;
73
74   /* maximum number of sessions */
75   u32 sessions;
76
77   /* maximum number of ssessions per user */
78   u32 user_sessions;
79 } nat44_config_t;
80
81 typedef enum
82 {
83   NAT_NEXT_DROP,
84   NAT_NEXT_ICMP_ERROR,
85   NAT_NEXT_IN2OUT_ED_FAST_PATH,
86   NAT_NEXT_IN2OUT_ED_SLOW_PATH,
87   NAT_NEXT_IN2OUT_ED_OUTPUT_FAST_PATH,
88   NAT_NEXT_IN2OUT_ED_OUTPUT_SLOW_PATH,
89   NAT_NEXT_OUT2IN_ED_FAST_PATH,
90   NAT_NEXT_OUT2IN_ED_SLOW_PATH,
91   NAT_NEXT_IN2OUT_CLASSIFY,
92   NAT_NEXT_OUT2IN_CLASSIFY,
93   NAT_N_NEXT,
94 } nat_next_t;
95
96 typedef struct
97 {
98   u32 next_index;
99   u32 arc_next_index;
100 } nat_pre_trace_t;
101
102 /* user (internal host) key */
103 typedef struct
104 {
105   union
106   {
107     struct
108     {
109       ip4_address_t addr;
110       u32 fib_index;
111     };
112     u64 as_u64;
113   };
114 } snat_user_key_t;
115
116 /* External address and port allocation modes */
117 #define foreach_nat_addr_and_port_alloc_alg \
118   _(0, DEFAULT, "default")         \
119   _(1, MAPE, "map-e")              \
120   _(2, RANGE, "port-range")
121
122 typedef enum
123 {
124 #define _(v, N, s) NAT_ADDR_AND_PORT_ALLOC_ALG_##N = v,
125   foreach_nat_addr_and_port_alloc_alg
126 #undef _
127 } nat_addr_and_port_alloc_alg_t;
128
129 /* Session state */
130 #define foreach_snat_session_state          \
131   _(0, UNKNOWN, "unknown")                 \
132   _(1, UDP_ACTIVE, "udp-active")           \
133   _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
134   _(3, TCP_ESTABLISHED, "tcp-established") \
135   _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
136   _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
137   _(6, TCP_CLOSING, "tcp-closing")         \
138   _(7, TCP_LAST_ACK, "tcp-last-ack")       \
139   _(8, TCP_CLOSED, "tcp-closed")           \
140   _(9, ICMP_ACTIVE, "icmp-active")
141
142 typedef enum
143 {
144 #define _(v, N, s) SNAT_SESSION_##N = v,
145   foreach_snat_session_state
146 #undef _
147 } snat_session_state_t;
148
149 #define foreach_nat_in2out_ed_error                     \
150 _(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
151 _(OUT_OF_PORTS, "out of ports")                         \
152 _(BAD_ICMP_TYPE, "unsupported ICMP type")               \
153 _(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
154 _(NON_SYN, "non-SYN packet try to create session")      \
155 _(TCP_CLOSED, "drops due to TCP in transitory timeout")
156
157 typedef enum
158 {
159 #define _(sym,str) NAT_IN2OUT_ED_ERROR_##sym,
160   foreach_nat_in2out_ed_error
161 #undef _
162     NAT_IN2OUT_ED_N_ERROR,
163 } nat_in2out_ed_error_t;
164
165 #define foreach_nat_out2in_ed_error                                           \
166   _ (UNSUPPORTED_PROTOCOL, "unsupported protocol")                            \
167   _ (OUT_OF_PORTS, "out of ports")                                            \
168   _ (BAD_ICMP_TYPE, "unsupported ICMP type")                                  \
169   _ (NO_TRANSLATION, "no translation")                                        \
170   _ (MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")                      \
171   _ (MAX_USER_SESS_EXCEEDED, "max user sessions exceeded")                    \
172   _ (CANNOT_CREATE_USER, "cannot create NAT user")                            \
173   _ (NON_SYN, "non-SYN packet try to create session")                         \
174   _ (TCP_CLOSED, "drops due to TCP in transitory timeout")                    \
175   _ (HASH_ADD_FAILED, "hash table add failed")
176
177 typedef enum
178 {
179 #define _(sym,str) NAT_OUT2IN_ED_ERROR_##sym,
180   foreach_nat_out2in_ed_error
181 #undef _
182     NAT_OUT2IN_ED_N_ERROR,
183 } nat_out2in_ed_error_t;
184
185
186 /* Endpoint dependent TCP session state */
187 #define NAT44_SES_I2O_FIN 1
188 #define NAT44_SES_O2I_FIN 2
189 #define NAT44_SES_I2O_FIN_ACK 4
190 #define NAT44_SES_O2I_FIN_ACK 8
191 #define NAT44_SES_I2O_SYN 16
192 #define NAT44_SES_O2I_SYN 32
193 #define NAT44_SES_RST     64
194
195 /* Session flags */
196 #define SNAT_SESSION_FLAG_STATIC_MAPPING     (1 << 0)
197 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO      (1 << 1)
198 #define SNAT_SESSION_FLAG_LOAD_BALANCING     (1 << 2)
199 #define SNAT_SESSION_FLAG_TWICE_NAT          (1 << 3)
200 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT (1 << 4)
201 #define SNAT_SESSION_FLAG_FWD_BYPASS         (1 << 5)
202 #define SNAT_SESSION_FLAG_AFFINITY           (1 << 6)
203 #define SNAT_SESSION_FLAG_EXACT_ADDRESS      (1 << 7)
204 #define SNAT_SESSION_FLAG_HAIRPINNING        (1 << 8)
205
206 /* NAT interface flags */
207 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
208 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
209
210 /* Static mapping flags */
211 #define NAT_STATIC_MAPPING_FLAG_ADDR_ONLY      1
212 #define NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY    2
213 #define NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT   4
214 #define NAT_STATIC_MAPPING_FLAG_LB             8
215 #define NAT_STATIC_MAPPING_FLAG_EXACT_ADDRESS  16
216
217 /* *INDENT-OFF* */
218 typedef CLIB_PACKED(struct
219 {
220   // number of sessions in this vrf
221   u32 ses_count;
222
223   u32 rx_fib_index;
224   u32 tx_fib_index;
225
226   // is this vrf expired
227   u8 expired;
228 }) per_vrf_sessions_t;
229 /* *INDENT-ON* */
230
231 typedef struct
232 {
233   ip4_address_t saddr, daddr;
234   u32 fib_index;
235   u16 sport, dport;
236   u16 icmp_id;
237   u8 proto;
238 } nat_6t_t;
239
240 typedef struct
241 {
242 #define NAT_FLOW_OP_SADDR_REWRITE   (1 << 1)
243 #define NAT_FLOW_OP_SPORT_REWRITE   (1 << 2)
244 #define NAT_FLOW_OP_DADDR_REWRITE   (1 << 3)
245 #define NAT_FLOW_OP_DPORT_REWRITE   (1 << 4)
246 #define NAT_FLOW_OP_ICMP_ID_REWRITE (1 << 5)
247 #define NAT_FLOW_OP_TXFIB_REWRITE   (1 << 6)
248   int ops;
249   nat_6t_t match;
250   nat_6t_t rewrite;
251   uword l3_csum_delta;
252   uword l4_csum_delta;
253 } nat_6t_flow_t;
254
255 always_inline void
256 nat_6t_flow_saddr_rewrite_set (nat_6t_flow_t *f, u32 saddr)
257 {
258   f->ops |= NAT_FLOW_OP_SADDR_REWRITE;
259   f->rewrite.saddr.as_u32 = saddr;
260 }
261
262 always_inline void
263 nat_6t_flow_daddr_rewrite_set (nat_6t_flow_t *f, u32 daddr)
264 {
265   f->ops |= NAT_FLOW_OP_DADDR_REWRITE;
266   f->rewrite.daddr.as_u32 = daddr;
267 }
268
269 always_inline void
270 nat_6t_flow_sport_rewrite_set (nat_6t_flow_t *f, u32 sport)
271 {
272   f->ops |= NAT_FLOW_OP_SPORT_REWRITE;
273   f->rewrite.sport = sport;
274 }
275
276 always_inline void
277 nat_6t_flow_dport_rewrite_set (nat_6t_flow_t *f, u32 dport)
278 {
279   f->ops |= NAT_FLOW_OP_DPORT_REWRITE;
280   f->rewrite.dport = dport;
281 }
282
283 always_inline void
284 nat_6t_flow_txfib_rewrite_set (nat_6t_flow_t *f, u32 tx_fib_index)
285 {
286   f->ops |= NAT_FLOW_OP_TXFIB_REWRITE;
287   f->rewrite.fib_index = tx_fib_index;
288 }
289
290 always_inline void
291 nat_6t_flow_icmp_id_rewrite_set (nat_6t_flow_t *f, u16 id)
292 {
293   f->ops |= NAT_FLOW_OP_ICMP_ID_REWRITE;
294   f->rewrite.icmp_id = id;
295 }
296
297 /* *INDENT-OFF* */
298 typedef CLIB_PACKED(struct
299 {
300   /* Outside network tuple */
301   struct
302   {
303     ip4_address_t addr;
304     u32 fib_index;
305     u16 port;
306   } out2in;
307
308   /* Inside network tuple */
309   struct
310   {
311     ip4_address_t addr;
312     u32 fib_index;
313     u16 port;
314   } in2out;
315
316   nat_protocol_t nat_proto;
317
318   nat_6t_flow_t i2o;
319   nat_6t_flow_t o2i;
320
321   /* Flags */
322   u32 flags;
323
324   /* Per-user translations */
325   u32 per_user_index;
326   u32 per_user_list_head_index;
327
328   /* head of LRU list in which this session is tracked */
329   u32 lru_head_index;
330   /* index in global LRU list */
331   u32 lru_index;
332   f64 last_lru_update;
333
334   /* Last heard timer */
335   f64 last_heard;
336
337   /* Last HA refresh */
338   f64 ha_last_refreshed;
339
340   /* Counters */
341   u64 total_bytes;
342   u32 total_pkts;
343
344   /* External host address and port */
345   ip4_address_t ext_host_addr;
346   u16 ext_host_port;
347
348   /* External host address and port after translation */
349   ip4_address_t ext_host_nat_addr;
350   u16 ext_host_nat_port;
351
352   /* TCP session state */
353   u8 state;
354   u32 i2o_fin_seq;
355   u32 o2i_fin_seq;
356   u64 tcp_closed_timestamp;
357
358   /* user index */
359   u32 user_index;
360
361   /* per vrf sessions index */
362   u32 per_vrf_sessions_index;
363
364 }) snat_session_t;
365 /* *INDENT-ON* */
366
367 typedef struct
368 {
369   ip4_address_t addr;
370   u32 fib_index;
371   u32 sessions_per_user_list_head_index;
372   u32 nsessions;
373   u32 nstaticsessions;
374 } snat_user_t;
375
376 typedef struct
377 {
378   ip4_address_t addr;
379   u32 fib_index;
380 /* *INDENT-OFF* */
381 #define _(N, i, n, s) \
382   u32 busy_##n##_ports; \
383   u32 * busy_##n##_ports_per_thread; \
384   u32 busy_##n##_port_refcounts[65535];
385   foreach_nat_protocol
386 #undef _
387 /* *INDENT-ON* */
388 } snat_address_t;
389
390 typedef struct
391 {
392   u32 fib_index;
393   u32 ref_count;
394 } nat_fib_t;
395
396 typedef struct
397 {
398   u32 fib_index;
399   u32 refcount;
400 } nat_outside_fib_t;
401
402 typedef struct
403 {
404   /* backend IP address */
405   ip4_address_t addr;
406   /* backend port number */
407   u16 port;
408   /* probability of the backend to be randomly matched */
409   u8 probability;
410   u8 prefix;
411   /* backend FIB table */
412   u32 vrf_id;
413   u32 fib_index;
414 } nat44_lb_addr_port_t;
415
416 typedef enum
417 {
418   /* twice-nat disabled */
419   TWICE_NAT_DISABLED,
420   /* twice-nat enabled */
421   TWICE_NAT,
422   /* twice-nat only when src IP equals dst IP after translation */
423   TWICE_NAT_SELF,
424 } twice_nat_type_t;
425
426 typedef enum
427 {
428   /* no load-balancing */
429   NO_LB_NAT,
430   /* load-balancing */
431   LB_NAT,
432   /* load-balancing with affinity */
433   AFFINITY_LB_NAT,
434 } lb_nat_type_t;
435
436 typedef struct
437 {
438   /* prefered pool address */
439   ip4_address_t pool_addr;
440   /* local IP address */
441   ip4_address_t local_addr;
442   /* external IP address */
443   ip4_address_t external_addr;
444   /* local port */
445   u16 local_port;
446   /* external port */
447   u16 external_port;
448   /* is twice-nat */
449   twice_nat_type_t twice_nat;
450   /* local FIB table */
451   u32 vrf_id;
452   u32 fib_index;
453   /* protocol */
454   nat_protocol_t proto;
455   /* 0 = disabled, otherwise client IP affinity sticky time in seconds */
456   u32 affinity;
457   /* worker threads used by backends/local host */
458   u32 *workers;
459   /* opaque string tag */
460   u8 *tag;
461   /* backends for load-balancing mode */
462   nat44_lb_addr_port_t *locals;
463   /* affinity per service lis */
464   u32 affinity_per_service_list_head_index;
465   /* flags */
466   u32 flags;
467 } snat_static_mapping_t;
468
469 typedef struct
470 {
471   u32 sw_if_index;
472   u8 flags;
473 } snat_interface_t;
474
475 typedef struct
476 {
477   ip4_address_t l_addr;
478   ip4_address_t pool_addr;
479   u16 l_port;
480   u16 e_port;
481   u32 sw_if_index;
482   u32 vrf_id;
483   nat_protocol_t proto;
484   u32 flags;
485   int addr_only;
486   int twice_nat;
487   int out2in_only;
488   int identity_nat;
489   int exact;
490   u8 *tag;
491 } snat_static_map_resolve_t;
492
493 typedef struct
494 {
495   /* Main lookup tables */
496   clib_bihash_8_8_t out2in;
497   clib_bihash_8_8_t in2out;
498
499   /* Find-a-user => src address lookup */
500   clib_bihash_8_8_t user_hash;
501
502   /* User pool */
503   snat_user_t *users;
504
505   /* Session pool */
506   snat_session_t *sessions;
507
508   /* Pool of doubly-linked list elements */
509   dlist_elt_t *list_pool;
510
511   /* LRU session list - head is stale, tail is fresh */
512   dlist_elt_t *lru_pool;
513   u32 tcp_trans_lru_head_index;
514   u32 tcp_estab_lru_head_index;
515   u32 udp_lru_head_index;
516   u32 icmp_lru_head_index;
517   u32 unk_proto_lru_head_index;
518
519   /* NAT thread index */
520   u32 snat_thread_index;
521
522   /* real thread index */
523   u32 thread_index;
524
525   per_vrf_sessions_t *per_vrf_sessions_vec;
526
527 } snat_main_per_thread_data_t;
528
529 struct snat_main_s;
530
531 /* ICMP session match function */
532 typedef u32 (snat_icmp_match_function_t) (struct snat_main_s * sm,
533                                           vlib_node_runtime_t * node,
534                                           u32 thread_index,
535                                           vlib_buffer_t * b0,
536                                           ip4_header_t * ip0,
537                                           ip4_address_t * addr,
538                                           u16 * port,
539                                           u32 * fib_index,
540                                           nat_protocol_t * proto,
541                                           void *d, void *e,
542                                           u8 * dont_translate);
543
544 /* Return worker thread index for given packet */
545 typedef u32 (snat_get_worker_in2out_function_t) (ip4_header_t * ip,
546                                                  u32 rx_fib_index,
547                                                  u8 is_output);
548
549 typedef u32 (snat_get_worker_out2in_function_t) (vlib_buffer_t * b,
550                                                  ip4_header_t * ip,
551                                                  u32 rx_fib_index,
552                                                  u8 is_output);
553
554 /* NAT address and port allocation function */
555 typedef int (nat_alloc_out_addr_and_port_function_t) (snat_address_t *
556                                                       addresses,
557                                                       u32 fib_index,
558                                                       u32 thread_index,
559                                                       nat_protocol_t proto,
560                                                       ip4_address_t * addr,
561                                                       u16 * port,
562                                                       u16 port_per_thread,
563                                                       u32 snat_thread_index);
564
565 #define foreach_nat_counter _ (tcp) _ (udp) _ (icmp) _ (other) _ (drops)
566
567 typedef struct snat_main_s
568 {
569   /* ICMP session match functions */
570   snat_icmp_match_function_t *icmp_match_in2out_cb;
571   snat_icmp_match_function_t *icmp_match_out2in_cb;
572
573   /* Thread settings */
574   u32 num_workers;
575   u32 first_worker_index;
576   u32 *workers;
577   snat_get_worker_in2out_function_t *worker_in2out_cb;
578   snat_get_worker_out2in_function_t *worker_out2in_cb;
579   u16 port_per_thread;
580
581   /* Per thread data */
582   snat_main_per_thread_data_t *per_thread_data;
583
584   /* Find a static mapping by local */
585   clib_bihash_8_8_t static_mapping_by_local;
586
587   /* Find a static mapping by external */
588   clib_bihash_8_8_t static_mapping_by_external;
589
590   /* Static mapping pool */
591   snat_static_mapping_t *static_mappings;
592
593   /* Endpoint dependent lookup table */
594   clib_bihash_16_8_t flow_hash;
595
596   /* Interface pool */
597   snat_interface_t *interfaces;
598   snat_interface_t *output_feature_interfaces;
599
600   /* Vector of outside addresses */
601   snat_address_t *addresses;
602   /* Address and port allocation function */
603   nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
604   /* Address and port allocation type */
605   nat_addr_and_port_alloc_alg_t addr_and_port_alloc_alg;
606   /* Port set parameters (MAP-E) */
607   u8 psid_offset;
608   u8 psid_length;
609   u16 psid;
610   /* Port range parameters */
611   u16 start_port;
612   u16 end_port;
613
614   /* vector of fibs */
615   nat_fib_t *fibs;
616
617   /* vector of outside fibs */
618   nat_outside_fib_t *outside_fibs;
619
620   /* Vector of twice NAT addresses for external hosts */
621   snat_address_t *twice_nat_addresses;
622
623   /* sw_if_indices whose intfc addresses should be auto-added */
624   u32 *auto_add_sw_if_indices;
625   u32 *auto_add_sw_if_indices_twice_nat;
626
627   /* vector of interface address static mappings to resolve. */
628   snat_static_map_resolve_t *to_resolve;
629
630   /* Randomize port allocation order */
631   u32 random_seed;
632
633   /* Worker handoff frame-queue index */
634   u32 fq_in2out_index;
635   u32 fq_in2out_output_index;
636   u32 fq_out2in_index;
637
638   /* node indexes */
639   u32 error_node_index;
640
641   /* handoff fq nodes  */
642   u32 handoff_out2in_index;
643   u32 handoff_in2out_index;
644   u32 handoff_in2out_output_index;
645
646   /* respect feature arc nodes */
647   u32 pre_out2in_node_index;
648   u32 pre_in2out_node_index;
649
650   u32 out2in_node_index;
651   u32 in2out_node_index;
652   u32 in2out_output_node_index;
653
654   u32 in2out_fast_node_index;
655   u32 in2out_slowpath_node_index;
656   u32 in2out_slowpath_output_node_index;
657   u32 out2in_fast_node_index;
658
659   u32 ei_out2in_node_index;
660   u32 ei_in2out_node_index;
661   u32 ei_in2out_output_node_index;
662
663   u32 ed_out2in_node_index;
664   u32 ed_in2out_node_index;
665   u32 ed_in2out_output_node_index;
666
667   u32 ed_in2out_slowpath_node_index;
668   u32 ed_out2in_slowpath_node_index;
669
670   u32 hairpinning_node_index;
671   u32 hairpin_dst_node_index;
672   u32 hairpin_src_node_index;
673
674   nat44_config_t rconfig;
675   //nat44_config_t cconfig;
676
677   /* If forwarding is enabled */
678   u8 forwarding_enabled;
679
680   /* Config parameters */
681   u8 endpoint_dependent;
682
683   u8 out2in_dpo;
684   /* static mapping config */
685   u8 static_mapping_only;
686   u8 static_mapping_connection_tracking;
687
688   /* Is translation memory size calculated or user defined */
689   u8 translation_memory_size_set;
690
691   u32 translation_buckets;
692   u32 max_translations_per_thread;
693   u32 *max_translations_per_fib;
694   u32 max_users_per_thread;
695   u32 user_buckets;
696   u32 max_translations_per_user;
697
698   u32 outside_vrf_id;
699   u32 outside_fib_index;
700   u32 inside_vrf_id;
701   u32 inside_fib_index;
702
703   nat_timeouts_t timeouts;
704
705   /* TCP MSS clamping */
706   u16 mss_clamping;
707
708   /* counters */
709   vlib_simple_counter_main_t total_users;
710   vlib_simple_counter_main_t total_sessions;
711   vlib_simple_counter_main_t user_limit_reached;
712
713 #define _(x) vlib_simple_counter_main_t x;
714   struct
715   {
716     struct
717     {
718       struct
719       {
720         foreach_nat_counter;
721       } in2out;
722
723       struct
724       {
725         foreach_nat_counter;
726       } out2in;
727
728       struct
729       {
730         foreach_nat_counter;
731       } in2out_ed;
732
733       struct
734       {
735         foreach_nat_counter;
736       } out2in_ed;
737     } fastpath;
738
739     struct
740     {
741       struct
742       {
743         foreach_nat_counter;
744       } in2out;
745
746       struct
747       {
748         foreach_nat_counter;
749       } out2in;
750
751       struct
752       {
753         foreach_nat_counter;
754       } in2out_ed;
755
756       struct
757       {
758         foreach_nat_counter;
759       } out2in_ed;
760     } slowpath;
761
762     vlib_simple_counter_main_t hairpinning;
763   } counters;
764 #undef _
765
766   /* API message ID base */
767   u16 msg_id_base;
768
769   /* log class */
770   vlib_log_class_t log_class;
771   /* logging level */
772   u8 log_level;
773
774   /* convenience */
775   api_main_t *api_main;
776   ip4_main_t *ip4_main;
777   ip_lookup_main_t *ip4_lookup_main;
778
779   fib_source_t fib_src_hi;
780   fib_source_t fib_src_low;
781
782   /* pat - dynamic mapping enabled or conneciton tracking */
783   u8 pat;
784
785   /* nat44 plugin enabled */
786   u8 enabled;
787
788   vnet_main_t *vnet_main;
789 } snat_main_t;
790
791 typedef struct
792 {
793   u32 thread_index;
794   f64 now;
795 } nat44_is_idle_session_ctx_t;
796
797 typedef struct
798 {
799   u32 cached_sw_if_index;
800   u32 cached_ip4_address;
801 } snat_runtime_t;
802
803 extern snat_main_t snat_main;
804
805 // nat pre ed next_node feature classification
806 extern vlib_node_registration_t nat_default_node;
807 extern vlib_node_registration_t nat_pre_in2out_node;
808 extern vlib_node_registration_t nat_pre_out2in_node;
809
810 extern vlib_node_registration_t snat_in2out_node;
811 extern vlib_node_registration_t snat_in2out_output_node;
812 extern vlib_node_registration_t snat_out2in_node;
813 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
814 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
815 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
816 extern vlib_node_registration_t nat44_ed_in2out_node;
817 extern vlib_node_registration_t nat44_ed_in2out_output_node;
818 extern vlib_node_registration_t nat44_ed_out2in_node;
819
820 extern fib_source_t nat_fib_src_hi;
821 extern fib_source_t nat_fib_src_low;
822
823 /* format functions */
824 format_function_t format_snat_user;
825 format_function_t format_snat_static_mapping;
826 format_function_t format_snat_static_map_to_resolve;
827 format_function_t format_snat_session;
828 format_function_t format_snat_key;
829 format_function_t format_static_mapping_key;
830 format_function_t format_nat_protocol;
831 format_function_t format_nat_addr_and_port_alloc_alg;
832 /* unformat functions */
833 unformat_function_t unformat_nat_protocol;
834
835 /** \brief Check if SNAT session is created from static mapping.
836     @param s SNAT session
837     @return 1 if SNAT session is created from static mapping otherwise 0
838 */
839 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
840
841 /** \brief Check if SNAT session for unknown protocol.
842     @param s SNAT session
843     @return 1 if SNAT session for unknown protocol otherwise 0
844 */
845 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
846
847 /** \brief Check if NAT session is twice NAT.
848     @param s NAT session
849     @return 1 if NAT session is twice NAT
850 */
851 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
852
853 /** \brief Check if NAT session is load-balancing.
854     @param s NAT session
855     @return 1 if NAT session is load-balancing
856 */
857 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
858
859 /** \brief Check if NAT session is forwarding bypass.
860     @param s NAT session
861     @return 1 if NAT session is load-balancing
862 */
863 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
864
865 /** \brief Check if NAT session is endpoint dependent.
866     @param s NAT session
867     @return 1 if NAT session is endpoint dependent
868 */
869 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
870
871 /** \brief Check if NAT session has affinity record.
872     @param s NAT session
873     @return 1 if NAT session has affinity record
874 */
875 #define is_affinity_sessions(s) (s->flags & SNAT_SESSION_FLAG_AFFINITY)
876
877 /** \brief Check if exact pool address should be used.
878     @param s SNAT session
879     @return 1 if exact pool address or 0
880 */
881 #define is_exact_address_session(s) (s->flags & SNAT_SESSION_FLAG_EXACT_ADDRESS)
882
883 /** \brief Check if NAT interface is inside.
884     @param i NAT interface
885     @return 1 if inside interface
886 */
887 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
888
889 /** \brief Check if NAT interface is outside.
890     @param i NAT interface
891     @return 1 if outside interface
892 */
893 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
894
895 /** \brief Check if NAT44 endpoint-dependent TCP session is closed.
896     @param s NAT session
897     @return 1 if session is closed
898 */
899 #define nat44_is_ses_closed(s) s->state == 0xf
900
901 /** \brief Check if NAT static mapping is address only (1:1NAT).
902     @param sm NAT static mapping
903     @return 1 if 1:1NAT, 0 if 1:1NAPT
904 */
905 #define is_addr_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_ADDR_ONLY)
906
907 /** \brief Check if NAT static mapping match only out2in direction.
908     @param sm NAT static mapping
909     @return 1 if rule match only out2in direction
910 */
911 #define is_out2in_only_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_OUT2IN_ONLY)
912
913 /** \brief Check if NAT static mapping is identity NAT.
914     @param sm NAT static mapping
915     @return 1 if identity NAT
916 */
917 #define is_identity_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_IDENTITY_NAT)
918
919 /** \brief Check if NAT static mapping is load-balancing.
920     @param sm NAT static mapping
921     @return 1 if load-balancing
922 */
923 #define is_lb_static_mapping(sm) (sm->flags & NAT_STATIC_MAPPING_FLAG_LB)
924
925 /** \brief Check if exact pool address should be used.
926     @param s SNAT session
927     @return 1 if exact pool address or 0
928 */
929 #define is_exact_address(s) (s->flags & NAT_STATIC_MAPPING_FLAG_EXACT_ADDRESS)
930
931 /** \brief Check if client initiating TCP connection (received SYN from client)
932     @param t TCP header
933     @return 1 if client initiating TCP connection
934 */
935 always_inline bool
936 tcp_flags_is_init (u8 f)
937 {
938   return (f & TCP_FLAG_SYN) && !(f & TCP_FLAG_ACK);
939 }
940
941 /* logging */
942 #define nat_log_err(...) \
943   vlib_log(VLIB_LOG_LEVEL_ERR, snat_main.log_class, __VA_ARGS__)
944 #define nat_log_warn(...) \
945   vlib_log(VLIB_LOG_LEVEL_WARNING, snat_main.log_class, __VA_ARGS__)
946 #define nat_log_notice(...) \
947   vlib_log(VLIB_LOG_LEVEL_NOTICE, snat_main.log_class, __VA_ARGS__)
948 #define nat_log_info(...) \
949   vlib_log(VLIB_LOG_LEVEL_INFO, snat_main.log_class, __VA_ARGS__)
950 #define nat_log_debug(...)\
951   vlib_log(VLIB_LOG_LEVEL_DEBUG, snat_main.log_class, __VA_ARGS__)
952
953 /* NAT API Logging Levels */
954 #define foreach_nat_log_level \
955   _(0x00, LOG_NONE)           \
956   _(0x01, LOG_ERROR)          \
957   _(0x02, LOG_WARNING)        \
958   _(0x03, LOG_NOTICE)         \
959   _(0x04, LOG_INFO)           \
960   _(0x05, LOG_DEBUG)
961
962 typedef enum nat_log_level_t_
963 {
964 #define _(n,f) SNAT_##f = n,
965   foreach_nat_log_level
966 #undef _
967 } nat_log_level_t;
968
969 #define nat_elog(_level, _str)                           \
970 do                                                       \
971   {                                                      \
972     snat_main_t *sm = &snat_main;                        \
973     if (PREDICT_FALSE (sm->log_level >= _level))         \
974       {                                                  \
975         ELOG_TYPE_DECLARE (e) =                          \
976           {                                              \
977             .format = "nat-msg " _str,                   \
978             .format_args = "",                           \
979           };                                             \
980         ELOG_DATA (&vlib_global_main.elog_main, e);      \
981       }                                                  \
982   } while (0);
983
984 #define nat_elog_addr(_level, _str, _addr)               \
985 do                                                       \
986   {                                                      \
987     if (PREDICT_FALSE (sm->log_level >= _level))         \
988       {                                                  \
989         ELOG_TYPE_DECLARE (e) =                          \
990           {                                              \
991             .format = "nat-msg " _str " %d.%d.%d.%d",    \
992             .format_args = "i1i1i1i1",                   \
993           };                                             \
994         CLIB_PACKED(struct                               \
995           {                                              \
996             u8 oct1;                                     \
997             u8 oct2;                                     \
998             u8 oct3;                                     \
999             u8 oct4;                                     \
1000           }) *ed;                                        \
1001         ed = ELOG_DATA (&vlib_global_main.elog_main, e); \
1002         ed->oct4 = _addr >> 24;                          \
1003         ed->oct3 = _addr >> 16;                          \
1004         ed->oct2 = _addr >> 8;                           \
1005         ed->oct1 = _addr;                                \
1006     }                                                    \
1007   } while (0);
1008
1009 #define nat_elog_debug_handoff(_str, _tid, _fib, _src, _dst)                \
1010 do                                                                          \
1011   {                                                                         \
1012   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                      \
1013     {                                                                       \
1014       ELOG_TYPE_DECLARE (e) =                                               \
1015         {                                                                   \
1016           .format = "nat-msg " _str " ip src: %d.%d.%d.%d dst: %d.%d.%d.%d" \
1017                                     " tid from: %d to: %d fib: %d",         \
1018         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                            \
1019       };                                                                    \
1020       CLIB_PACKED(struct                                                    \
1021         {                                                                   \
1022           u8 src_oct1;                                                      \
1023           u8 src_oct2;                                                      \
1024           u8 src_oct3;                                                      \
1025           u8 src_oct4;                                                      \
1026           u8 dst_oct1;                                                      \
1027           u8 dst_oct2;                                                      \
1028           u8 dst_oct3;                                                      \
1029           u8 dst_oct4;                                                      \
1030           u32 ftid;                                                         \
1031           u32 ttid;                                                         \
1032           u32 fib;                                                          \
1033         }) *ed;                                                             \
1034       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                      \
1035       ed->src_oct1 = _src >> 24;                                            \
1036       ed->src_oct2 = _src >> 16;                                            \
1037       ed->src_oct3 = _src >> 8;                                             \
1038       ed->src_oct4 = _src;                                                  \
1039       ed->dst_oct1 = _dst >> 24;                                            \
1040       ed->dst_oct2 = _dst >> 16;                                            \
1041       ed->dst_oct3 = _dst >> 8;                                             \
1042       ed->dst_oct4 = _dst;                                                  \
1043       ed->ftid = vlib_get_thread_index ();                                  \
1044       ed->ttid = _tid;                                                      \
1045       ed->fib = _fib;                                                       \
1046     }                                                                       \
1047   } while (0);
1048
1049 #define nat_elog_debug_handoff_v2(_str, _prt, _fib, _src, _dst)              \
1050 do                                                                           \
1051   {                                                                          \
1052   if (PREDICT_FALSE (sm->log_level >= SNAT_LOG_DEBUG))                       \
1053     {                                                                        \
1054       ELOG_TYPE_DECLARE (e) =                                                \
1055         {                                                                    \
1056           .format = "nat-msg " _str " ip_src:%d.%d.%d.%d ip_dst:%d.%d.%d.%d" \
1057                                     " tid:%d prt:%d fib:%d",                 \
1058         .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                             \
1059       };                                                                     \
1060       CLIB_PACKED(struct                                                     \
1061         {                                                                    \
1062           u8 src_oct1;                                                       \
1063           u8 src_oct2;                                                       \
1064           u8 src_oct3;                                                       \
1065           u8 src_oct4;                                                       \
1066           u8 dst_oct1;                                                       \
1067           u8 dst_oct2;                                                       \
1068           u8 dst_oct3;                                                       \
1069           u8 dst_oct4;                                                       \
1070           u32 tid;                                                           \
1071           u32 prt;                                                           \
1072           u32 fib;                                                           \
1073         }) *ed;                                                              \
1074       ed = ELOG_DATA (&vlib_global_main.elog_main, e);                       \
1075       ed->src_oct1 = _src >> 24;                                             \
1076       ed->src_oct2 = _src >> 16;                                             \
1077       ed->src_oct3 = _src >> 8;                                              \
1078       ed->src_oct4 = _src;                                                   \
1079       ed->dst_oct1 = _dst >> 24;                                             \
1080       ed->dst_oct2 = _dst >> 16;                                             \
1081       ed->dst_oct3 = _dst >> 8;                                              \
1082       ed->dst_oct4 = _dst;                                                   \
1083       ed->tid = vlib_get_thread_index ();                                    \
1084       ed->prt = _prt;                                                        \
1085       ed->fib = _fib;                                                        \
1086     }                                                                        \
1087   } while (0);
1088
1089 #define nat_elog_X1(_level, _fmt, _arg, _val1)            \
1090 do                                                        \
1091   {                                                       \
1092     snat_main_t *sm = &snat_main;                         \
1093     if (PREDICT_FALSE (sm->log_level >= _level))          \
1094       {                                                   \
1095         ELOG_TYPE_DECLARE (e) =                           \
1096           {                                               \
1097             .format = "nat-msg " _fmt,                    \
1098             .format_args = _arg,                          \
1099           };                                              \
1100         CLIB_PACKED(struct                                \
1101           {                                               \
1102             typeof (_val1) val1;                          \
1103           }) *ed;                                         \
1104         ed = ELOG_DATA (&vlib_global_main.elog_main, e);  \
1105         ed->val1 = _val1;                                 \
1106       }                                                   \
1107   } while (0);
1108
1109 #define nat_elog_notice(nat_elog_str) \
1110   nat_elog(SNAT_LOG_INFO, "[notice] " nat_elog_str)
1111 #define nat_elog_warn(nat_elog_str) \
1112   nat_elog(SNAT_LOG_WARNING, "[warning] " nat_elog_str)
1113 #define nat_elog_err(nat_elog_str) \
1114   nat_elog(SNAT_LOG_ERROR, "[error] " nat_elog_str)
1115 #define nat_elog_debug(nat_elog_str) \
1116   nat_elog(SNAT_LOG_DEBUG, "[debug] " nat_elog_str)
1117 #define nat_elog_info(nat_elog_str) \
1118   nat_elog(SNAT_LOG_INFO, "[info] " nat_elog_str)
1119
1120 #define nat_elog_notice_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1121   nat_elog_X1(SNAT_LOG_NOTICE, "[notice] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1122 #define nat_elog_warn_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1123   nat_elog_X1(SNAT_LOG_WARNING, "[warning] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1124 #define nat_elog_err_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1125   nat_elog_X1(SNAT_LOG_ERROR, "[error] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1126 #define nat_elog_debug_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1127   nat_elog_X1(SNAT_LOG_DEBUG, "[debug] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1128 #define nat_elog_info_X1(nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1) \
1129   nat_elog_X1(SNAT_LOG_INFO, "[info] " nat_elog_fmt_str, nat_elog_fmt_arg, nat_elog_val1)
1130
1131 /* ICMP session match functions */
1132 u32 icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1133                             u32 thread_index, vlib_buffer_t * b0,
1134                             ip4_header_t * ip0, ip4_address_t * addr,
1135                             u16 * port, u32 * fib_index,
1136                             nat_protocol_t * proto, void *d, void *e,
1137                             u8 * dont_translate);
1138 u32 icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1139                             u32 thread_index, vlib_buffer_t * b0,
1140                             ip4_header_t * ip0, ip4_address_t * addr,
1141                             u16 * port, u32 * fib_index,
1142                             nat_protocol_t * proto, void *d, void *e,
1143                             u8 * dont_translate);
1144 u32 icmp_match_out2in_fast (snat_main_t * sm, vlib_node_runtime_t * node,
1145                             u32 thread_index, vlib_buffer_t * b0,
1146                             ip4_header_t * ip0, ip4_address_t * addr,
1147                             u16 * port, u32 * fib_index,
1148                             nat_protocol_t * proto, void *d, void *e,
1149                             u8 * dont_translate);
1150 u32 icmp_match_out2in_slow (snat_main_t * sm, vlib_node_runtime_t * node,
1151                             u32 thread_index, vlib_buffer_t * b0,
1152                             ip4_header_t * ip0, ip4_address_t * addr,
1153                             u16 * port, u32 * fib_index,
1154                             nat_protocol_t * proto, void *d, void *e,
1155                             u8 * dont_translate);
1156
1157 u32 icmp_in2out (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1158                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1159                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1160                  void *d, void *e);
1161
1162 u32 icmp_out2in (snat_main_t * sm, vlib_buffer_t * b0, ip4_header_t * ip0,
1163                  icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0,
1164                  vlib_node_runtime_t * node, u32 next0, u32 thread_index,
1165                  void *d, void *e);
1166
1167 /* hairpinning functions */
1168 u32 snat_icmp_hairpinning (snat_main_t *sm, vlib_buffer_t *b0,
1169                            ip4_header_t *ip0, icmp46_header_t *icmp0);
1170
1171 void nat_hairpinning_sm_unknown_proto (snat_main_t * sm, vlib_buffer_t * b,
1172                                        ip4_header_t * ip);
1173 int snat_hairpinning (vlib_main_t *vm, vlib_node_runtime_t *node,
1174                       snat_main_t *sm, vlib_buffer_t *b0, ip4_header_t *ip0,
1175                       udp_header_t *udp0, tcp_header_t *tcp0, u32 proto0,
1176                       int do_trace);
1177
1178 /* Call back functions for clib_bihash_add_or_overwrite_stale */
1179 int nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1180 int nat44_o2i_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg);
1181
1182
1183 /**
1184  * @brief Enable NAT44 plugin
1185  *
1186  * @param c         nat44_config_t
1187  *
1188  * @return 0 on success, non-zero value otherwise
1189  */
1190 int nat44_plugin_enable (nat44_config_t c);
1191
1192 /**
1193  * @brief Disable NAT44 plugin
1194  *
1195  * @return 0 on success, non-zero value otherwise
1196  */
1197 int nat44_plugin_disable ();
1198
1199 /**
1200  * @brief Add external address to NAT44 pool
1201  *
1202  * @param sm        snat global configuration data
1203  * @param addr      IPv4 address
1204  * @param vrf_id    VRF id of tenant, ~0 means independent of VRF
1205  * @param twice_nat 1 if twice NAT address
1206  *
1207  * @return 0 on success, non-zero value otherwise
1208  */
1209 int snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
1210                       u8 twice_nat);
1211
1212 /**
1213  * @brief Delete external address from NAT44 pool
1214  *
1215  * @param sm        snat global configuration data
1216  * @param addr      IPv4 address
1217  * @param delete_sm 1 if delete static mapping using address
1218  * @param twice_nat 1 if twice NAT address
1219  *
1220  * @return 0 on success, non-zero value otherwise
1221  */
1222 int snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
1223                       u8 twice_nat);
1224
1225 /**
1226  * @brief Add/delete external address to FIB DPO (out2in DPO mode)
1227  *
1228  * @param addr   IPv4 address
1229  * @param is_add 1 = add, 0 = delete
1230  *
1231  * @return 0 on success, non-zero value otherwise
1232  */
1233 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
1234
1235 /**
1236  * @brief Add/delete NAT44 static mapping
1237  *
1238  * @param l_addr       local IPv4 address
1239  * @param e_addr       external IPv4 address
1240  * @param l_port       local port number
1241  * @param e_port       external port number
1242  * @param vrf_id       local VRF ID
1243  * @param addr_only    1 = 1:1NAT, 0 = 1:1NAPT
1244  * @param sw_if_index  use interface address as external IPv4 address
1245  * @param proto        L4 protocol
1246  * @param is_add       1 = add, 0 = delete
1247  * @param twice_nat    twice-nat mode
1248  * @param out2in_only  if 1 rule match only out2in direction
1249  * @param tag          opaque string tag
1250  * @param identity_nat identity NAT
1251  * @param pool_addr    pool IPv4 address
1252  * @param exact        1 = exact pool address
1253  *
1254  * @return 0 on success, non-zero value otherwise
1255  */
1256 int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
1257                              u16 l_port, u16 e_port, u32 vrf_id,
1258                              int addr_only, u32 sw_if_index,
1259                              nat_protocol_t proto, int is_add,
1260                              twice_nat_type_t twice_nat, u8 out2in_only,
1261                              u8 * tag, u8 identity_nat,
1262                              ip4_address_t pool_addr, int exact);
1263
1264 /**
1265  * @brief Add/delete static mapping with load-balancing (multiple backends)
1266  *
1267  * @param e_addr      external IPv4 address
1268  * @param e_port      external port number
1269  * @param proto       L4 protocol
1270  * @param locals      list of local backends
1271  * @param is_add      1 = add, 0 = delete
1272  * @param twice_nat   twice-nat mode
1273  * @param out2in_only if 1 rule match only out2in direction
1274  * @param tag         opaque string tag
1275  * @param affinity    0 = disabled, otherwise client IP affinity sticky time
1276  *
1277  * @return 0 on success, non-zero value otherwise
1278  */
1279 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
1280                                      nat_protocol_t proto,
1281                                      nat44_lb_addr_port_t * locals, u8 is_add,
1282                                      twice_nat_type_t twice_nat,
1283                                      u8 out2in_only, u8 * tag, u32 affinity);
1284
1285 int nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
1286                                            ip4_address_t l_addr, u16 l_port,
1287                                            nat_protocol_t proto, u32 vrf_id,
1288                                            u8 probability, u8 is_add);
1289
1290 clib_error_t *nat44_api_hookup (vlib_main_t * vm);
1291
1292 /**
1293  * @brief Set NAT plugin workers
1294  *
1295  * @param bitmap NAT workers bitmap
1296  *
1297  * @return 0 on success, non-zero value otherwise
1298  */
1299 int snat_set_workers (uword * bitmap);
1300
1301 /**
1302  * @brief Enable/disable NAT44 feature on the interface
1303  *
1304  * @param sw_if_index software index of the interface
1305  * @param is_inside   1 = inside, 0 = outside
1306  * @param is_del      1 = delete, 0 = add
1307  *
1308  * @return 0 on success, non-zero value otherwise
1309  */
1310 int snat_interface_add_del (u32 sw_if_index, u8 is_inside, int is_del);
1311
1312 /**
1313  * @brief Enable/disable NAT44 output feature on the interface (postrouting NAT)
1314  *
1315  * @param sw_if_index software index of the interface
1316  * @param is_inside   1 = inside, 0 = outside
1317  * @param is_del      1 = delete, 0 = add
1318  *
1319  * @return 0 on success, non-zero value otherwise
1320  */
1321 int snat_interface_add_del_output_feature (u32 sw_if_index, u8 is_inside,
1322                                            int is_del);
1323
1324 /**
1325  * @brief Add/delete NAT44 pool address from specific interface
1326  *
1327  * @param sw_if_index software index of the interface
1328  * @param is_del      1 = delete, 0 = add
1329  * @param twice_nat   1 = twice NAT address for external hosts
1330  *
1331  * @return 0 on success, non-zero value otherwise
1332  */
1333 int snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
1334                                 u8 twice_nat);
1335
1336 /**
1337  * @brief Delete NAT44 endpoint-dependent session
1338  *
1339  * @param sm     snat global configuration data
1340  * @param addr   IPv4 address
1341  * @param port   L4 port number
1342  * @param proto  L4 protocol
1343  * @param vrf_id VRF ID
1344  * @param is_in  1 = inside network address and port pair, 0 = outside
1345  *
1346  * @return 0 on success, non-zero value otherwise
1347  */
1348 int nat44_del_ed_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
1349                           ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1350                           u32 vrf_id, int is_in);
1351
1352 /**
1353  * @brief Free NAT44 session data (lookup keys, external address port)
1354  *
1355  * @param sm           snat global configuration data
1356  * @param s            NAT session
1357  * @param thread_index thread index
1358  * @param is_ha        is HA event
1359  */
1360 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
1361                             u32 thread_index, u8 is_ha);
1362
1363 /**
1364  * @brief Set NAT44 session limit (session limit, vrf id)
1365  *
1366  * @param session_limit Session limit
1367  * @param vrf_id        VRF id
1368  * @return 0 on success, non-zero value otherwise
1369  */
1370 int nat44_set_session_limit (u32 session_limit, u32 vrf_id);
1371
1372 /**
1373  * @brief Update NAT44 session limit flushing all data (session limit, vrf id)
1374  *
1375  * @param session_limit Session limit
1376  * @param vrf_id        VRF id
1377  * @return 0 on success, non-zero value otherwise
1378  */
1379 int nat44_update_session_limit (u32 session_limit, u32 vrf_id);
1380
1381 /**
1382  * @brief Free all NAT44 sessions
1383  */
1384 void nat44_sessions_clear ();
1385
1386 /**
1387  * @brief Find or create NAT user
1388  *
1389  * @param sm           snat global configuration data
1390  * @param addr         IPv4 address
1391  * @param fib_index    FIB table index
1392  * @param thread_index thread index
1393  *
1394  * @return NAT user data structure on success otherwise zero value
1395  */
1396 snat_user_t *nat_user_get_or_create (snat_main_t * sm,
1397                                      ip4_address_t * addr, u32 fib_index,
1398                                      u32 thread_index);
1399
1400 /**
1401  * @brief Allocate new NAT session or recycle last used
1402  *
1403  * @param sm           snat global configuration data
1404  * @param u            NAT user
1405  * @param thread_index thread index
1406  * @param now          time now
1407  *
1408  * @return session data structure on success otherwise zero value
1409  */
1410 snat_session_t *nat_session_alloc_or_recycle (snat_main_t * sm,
1411                                               snat_user_t * u,
1412                                               u32 thread_index, f64 now);
1413
1414 /**
1415  * @brief Free outside address and port pair
1416  *
1417  * @param addresses    vector of outside addresses
1418  * @param thread_index thread index
1419  * @param key          address, port and protocol
1420  */
1421 void
1422 snat_free_outside_address_and_port (snat_address_t * addresses,
1423                                     u32 thread_index,
1424                                     ip4_address_t * addr,
1425                                     u16 port, nat_protocol_t protocol);
1426
1427 void expire_per_vrf_sessions (u32 fib_index);
1428
1429 /**
1430  * @brief Match NAT44 static mapping.
1431  *
1432  * @param key             address and port to match
1433  * @param addr            external/local address of the matched mapping
1434  * @param port            port of the matched mapping
1435  * @param fib_index       fib index of the matched mapping
1436  * @param by_external     if 0 match by local address otherwise match by external
1437  *                        address
1438  * @param is_addr_only    1 if matched mapping is address only
1439  * @param twice_nat       matched mapping is twice NAT type
1440  * @param lb              1 if matched mapping is load-balanced
1441  * @param ext_host_addr   external host address
1442  * @param is_identity_nat 1 if indentity mapping
1443  * @param out             if !=0 set to pointer of the mapping structure
1444  *
1445  * @returns 0 if match found otherwise 1.
1446  */
1447 int snat_static_mapping_match (snat_main_t * sm,
1448                                ip4_address_t match_addr,
1449                                u16 match_port,
1450                                u32 match_fib_index,
1451                                nat_protocol_t match_protocol,
1452                                ip4_address_t * mapping_addr,
1453                                u16 * mapping_port,
1454                                u32 * mapping_fib_index,
1455                                u8 by_external,
1456                                u8 * is_addr_only,
1457                                twice_nat_type_t * twice_nat,
1458                                lb_nat_type_t * lb,
1459                                ip4_address_t * ext_host_addr,
1460                                u8 * is_identity_nat,
1461                                snat_static_mapping_t ** out);
1462
1463 /**
1464  * @brief Add/del NAT address to FIB.
1465  *
1466  * Add the external NAT address to the FIB as receive entries. This ensures
1467  * that VPP will reply to ARP for this address and we don't need to enable
1468  * proxy ARP on the outside interface.
1469  *
1470  * @param addr        IPv4 address
1471  * @param plen        address prefix length
1472  * @param sw_if_index software index of the outside interface
1473  * @param is_add      0 = delete, 1 = add.
1474  */
1475 void snat_add_del_addr_to_fib (ip4_address_t * addr,
1476                                u8 p_len, u32 sw_if_index, int is_add);
1477
1478 #if 0
1479 void
1480 nat_ha_sadd_ed_cb (ip4_address_t * in_addr, u16 in_port,
1481                    ip4_address_t * out_addr, u16 out_port,
1482                    ip4_address_t * eh_addr, u16 eh_port,
1483                    ip4_address_t * ehn_addr, u16 ehn_port, u8 proto,
1484                    u32 fib_index, u16 flags, u32 thread_index);
1485
1486 void
1487 nat_ha_sdel_ed_cb (ip4_address_t * out_addr, u16 out_port,
1488                    ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1489                    u32 fib_index, u32 ti);
1490
1491 void
1492 nat_ha_sref_ed_cb (ip4_address_t * out_addr, u16 out_port,
1493                    ip4_address_t * eh_addr, u16 eh_port, u8 proto,
1494                    u32 fib_index, u32 total_pkts, u64 total_bytes,
1495                    u32 thread_index);
1496 #endif
1497
1498 int nat_set_outside_address_and_port (snat_address_t *addresses,
1499                                       u32 thread_index, ip4_address_t addr,
1500                                       u16 port, nat_protocol_t protocol);
1501
1502 /*
1503  * Why is this here? Because we don't need to touch this layer to
1504  * simply reply to an icmp. We need to change id to a unique
1505  * value to NAT an echo request/reply.
1506  */
1507
1508 typedef struct
1509 {
1510   u16 identifier;
1511   u16 sequence;
1512 } icmp_echo_header_t;
1513
1514 typedef struct
1515 {
1516   u16 src_port, dst_port;
1517 } tcp_udp_header_t;
1518
1519 u8 *format_user_kvp (u8 * s, va_list * args);
1520
1521 u32 get_thread_idx_by_port (u16 e_port);
1522
1523 u8 *format_static_mapping_kvp (u8 *s, va_list *args);
1524
1525 u8 *format_session_kvp (u8 *s, va_list *args);
1526
1527 u8 *format_user_kvp (u8 *s, va_list *args);
1528
1529 u32 nat_calc_bihash_buckets (u32 n_elts);
1530
1531 void nat44_addresses_free (snat_address_t **addresses);
1532
1533 typedef enum
1534 {
1535   NAT_ED_TRNSL_ERR_SUCCESS = 0,
1536   NAT_ED_TRNSL_ERR_TRANSLATION_FAILED = 1,
1537   NAT_ED_TRNSL_ERR_FLOW_MISMATCH = 2,
1538 } nat_translation_error_e;
1539
1540 nat_translation_error_e
1541 nat_6t_flow_buf_translate (snat_main_t *sm, vlib_buffer_t *b, ip4_header_t *ip,
1542                            nat_6t_flow_t *f, nat_protocol_t proto,
1543                            int is_output_feature);
1544
1545 void nat_6t_l3_l4_csum_calc (nat_6t_flow_t *f);
1546
1547 format_function_t format_nat_ed_translation_error;
1548 format_function_t format_nat_6t_flow;
1549 format_function_t format_ed_session_kvp;
1550
1551 #endif /* __included_nat_h__ */
1552 /*
1553  * fd.io coding-style-patch-verification: ON
1554  *
1555  * Local Variables:
1556  * eval: (c-set-style "gnu")
1557  * End:
1558  */