3 * nat.h - NAT plugin definitions
5 * Copyright (c) 2016 Cisco and/or its affiliates.
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at:
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
18 #ifndef __included_nat_h__
19 #define __included_nat_h__
21 #include <vnet/vnet.h>
22 #include <vnet/ip/ip.h>
23 #include <vnet/ethernet/ethernet.h>
24 #include <vnet/ip/icmp46_packet.h>
25 #include <vnet/api_errno.h>
26 #include <vppinfra/bihash_8_8.h>
27 #include <vppinfra/bihash_16_8.h>
28 #include <vppinfra/dlist.h>
29 #include <vppinfra/error.h>
30 #include <vlibapi/api.h>
33 #define SNAT_UDP_TIMEOUT 300
34 #define SNAT_UDP_TIMEOUT_MIN 120
35 #define SNAT_TCP_TRANSITORY_TIMEOUT 240
36 #define SNAT_TCP_ESTABLISHED_TIMEOUT 7440
37 #define SNAT_TCP_INCOMING_SYN 6
38 #define SNAT_ICMP_TIMEOUT 60
40 #define SNAT_FLAG_HAIRPINNING (1 << 0)
78 ip4_address_t ext_host_addr;
99 #define foreach_snat_protocol \
100 _(UDP, 0, udp, "udp") \
101 _(TCP, 1, tcp, "tcp") \
102 _(ICMP, 2, icmp, "icmp")
105 #define _(N, i, n, s) SNAT_PROTOCOL_##N = i,
106 foreach_snat_protocol
111 #define foreach_snat_session_state \
112 _(0, UNKNOWN, "unknown") \
113 _(1, UDP_ACTIVE, "udp-active") \
114 _(2, TCP_SYN_SENT, "tcp-syn-sent") \
115 _(3, TCP_ESTABLISHED, "tcp-established") \
116 _(4, TCP_FIN_WAIT, "tcp-fin-wait") \
117 _(5, TCP_CLOSE_WAIT, "tcp-close-wait") \
118 _(6, TCP_LAST_ACK, "tcp-last-ack") \
119 _(7, ICMP_ACTIVE, "icmp-active")
122 #define _(v, N, s) SNAT_SESSION_##N = v,
123 foreach_snat_session_state
125 } snat_session_state_t;
128 #define SNAT_SESSION_FLAG_STATIC_MAPPING 1
129 #define SNAT_SESSION_FLAG_UNKNOWN_PROTO 2
130 #define SNAT_SESSION_FLAG_LOAD_BALANCING 4
131 #define SNAT_SESSION_FLAG_TWICE_NAT 8
132 #define SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT 16
133 #define SNAT_SESSION_FLAG_FWD_BYPASS 32
135 #define NAT_INTERFACE_FLAG_IS_INSIDE 1
136 #define NAT_INTERFACE_FLAG_IS_OUTSIDE 2
138 typedef CLIB_PACKED(struct {
139 snat_session_key_t out2in; /* 0-15 */
141 snat_session_key_t in2out; /* 16-31 */
143 u32 flags; /* 32-35 */
145 /* per-user translations */
146 u32 per_user_index; /* 36-39 */
148 u32 per_user_list_head_index; /* 40-43 */
150 /* Last heard timer */
151 f64 last_heard; /* 44-51 */
153 u64 total_bytes; /* 52-59 */
155 u32 total_pkts; /* 60-63 */
157 /* Outside address */
158 u32 outside_address_index; /* 64-67 */
160 /* External host address and port */
161 ip4_address_t ext_host_addr; /* 68-71 */
162 u16 ext_host_port; /* 72-73 */
164 /* External hos address and port after translation */
165 ip4_address_t ext_host_nat_addr; /* 74-77 */
166 u16 ext_host_nat_port; /* 78-79 */
173 u32 sessions_per_user_list_head_index;
181 #define _(N, i, n, s) \
182 u16 busy_##n##_ports; \
183 u16 * busy_##n##_ports_per_thread; \
184 uword * busy_##n##_port_bitmap;
185 foreach_snat_protocol
191 snat_det_out_key_t out;
194 } snat_det_session_t;
197 ip4_address_t in_addr;
199 ip4_address_t out_addr;
204 /* vector of sessions */
205 snat_det_session_t * sessions;
213 } nat44_lb_addr_port_t;
222 ip4_address_t local_addr;
223 ip4_address_t external_addr;
227 twice_nat_type_t twice_nat;
231 snat_protocol_t proto;
234 nat44_lb_addr_port_t *locals;
235 } snat_static_mapping_t;
243 ip4_address_t l_addr;
248 snat_protocol_t proto;
253 } snat_static_map_resolve_t;
256 /* Main lookup tables */
257 clib_bihash_8_8_t out2in;
258 clib_bihash_8_8_t in2out;
260 /* Find-a-user => src address lookup */
261 clib_bihash_8_8_t user_hash;
267 snat_session_t * sessions;
269 /* Pool of doubly-linked list elements */
270 dlist_elt_t * list_pool;
272 u32 snat_thread_index;
273 } snat_main_per_thread_data_t;
277 typedef u32 snat_icmp_match_function_t (struct snat_main_s *sm,
278 vlib_node_runtime_t *node,
283 snat_session_key_t *p_value,
284 u8 *p_dont_translate,
288 typedef u32 (snat_get_worker_function_t) (ip4_header_t * ip, u32 rx_fib_index);
290 typedef int nat_alloc_out_addr_and_port_function_t (snat_address_t * addresses,
293 snat_session_key_t * k,
294 u32 * address_indexp,
296 u32 snat_thread_index);
298 typedef struct snat_main_s {
299 /* Endpoint address dependent sessions lookup tables */
300 clib_bihash_16_8_t out2in_ed;
301 clib_bihash_16_8_t in2out_ed;
303 snat_icmp_match_function_t * icmp_match_in2out_cb;
304 snat_icmp_match_function_t * icmp_match_out2in_cb;
307 u32 first_worker_index;
310 snat_get_worker_function_t * worker_in2out_cb;
311 snat_get_worker_function_t * worker_out2in_cb;
315 /* Per thread data */
316 snat_main_per_thread_data_t * per_thread_data;
318 /* Find a static mapping by local */
319 clib_bihash_8_8_t static_mapping_by_local;
321 /* Find a static mapping by external */
322 clib_bihash_8_8_t static_mapping_by_external;
324 /* Static mapping pool */
325 snat_static_mapping_t * static_mappings;
328 snat_interface_t * interfaces;
329 snat_interface_t * output_feature_interfaces;
331 /* Vector of outside addresses */
332 snat_address_t * addresses;
333 nat_alloc_out_addr_and_port_function_t *alloc_addr_and_port;
338 /* Vector of twice NAT addresses for extenal hosts */
339 snat_address_t * twice_nat_addresses;
341 /* sw_if_indices whose intfc addresses should be auto-added */
342 u32 * auto_add_sw_if_indices;
343 u32 * auto_add_sw_if_indices_twice_nat;
345 /* vector of interface address static mappings to resolve. */
346 snat_static_map_resolve_t *to_resolve;
348 /* Randomize port allocation order */
351 /* Worker handoff index */
353 u32 fq_in2out_output_index;
356 /* in2out and out2in node index */
357 u32 in2out_node_index;
358 u32 in2out_output_node_index;
359 u32 out2in_node_index;
361 /* Deterministic NAT */
362 snat_det_map_t * det_maps;
364 /* If forwarding is enabled */
365 u8 forwarding_enabled;
367 /* Config parameters */
368 u8 static_mapping_only;
369 u8 static_mapping_connection_tracking;
372 u32 translation_buckets;
373 u32 translation_memory_size;
374 u32 max_translations;
376 u32 user_memory_size;
377 u32 max_translations_per_user;
379 u32 outside_fib_index;
381 u32 inside_fib_index;
383 /* values of various timeouts */
385 u32 tcp_established_timeout;
386 u32 tcp_transitory_timeout;
389 /* API message ID base */
393 vlib_main_t * vlib_main;
394 vnet_main_t * vnet_main;
395 ip4_main_t * ip4_main;
396 ip_lookup_main_t * ip4_lookup_main;
397 api_main_t * api_main;
400 extern snat_main_t snat_main;
401 extern vlib_node_registration_t snat_in2out_node;
402 extern vlib_node_registration_t snat_in2out_output_node;
403 extern vlib_node_registration_t snat_out2in_node;
404 extern vlib_node_registration_t snat_in2out_fast_node;
405 extern vlib_node_registration_t snat_out2in_fast_node;
406 extern vlib_node_registration_t snat_in2out_worker_handoff_node;
407 extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
408 extern vlib_node_registration_t snat_out2in_worker_handoff_node;
409 extern vlib_node_registration_t snat_det_in2out_node;
410 extern vlib_node_registration_t snat_det_out2in_node;
411 extern vlib_node_registration_t snat_hairpin_dst_node;
412 extern vlib_node_registration_t snat_hairpin_src_node;
414 void snat_free_outside_address_and_port (snat_address_t * addresses,
416 snat_session_key_t * k,
419 int snat_alloc_outside_address_and_port (snat_address_t * addresses,
422 snat_session_key_t * k,
423 u32 * address_indexp,
425 u32 snat_thread_index);
427 int snat_static_mapping_match (snat_main_t * sm,
428 snat_session_key_t match,
429 snat_session_key_t * mapping,
432 twice_nat_type_t *twice_nat,
435 void snat_add_del_addr_to_fib (ip4_address_t * addr,
440 format_function_t format_snat_user;
441 format_function_t format_snat_static_mapping;
442 format_function_t format_snat_static_map_to_resolve;
443 format_function_t format_det_map_ses;
446 u32 cached_sw_if_index;
447 u32 cached_ip4_address;
450 /** \brief Check if SNAT session is created from static mapping.
451 @param s SNAT session
452 @return 1 if SNAT session is created from static mapping otherwise 0
454 #define snat_is_session_static(s) (s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
456 /** \brief Check if SNAT session for unknown protocol.
457 @param s SNAT session
458 @return 1 if SNAT session for unknown protocol otherwise 0
460 #define snat_is_unk_proto_session(s) (s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO)
462 /** \brief Check if NAT session is twice NAT.
464 @return 1 if NAT session is twice NAT
466 #define is_twice_nat_session(s) (s->flags & SNAT_SESSION_FLAG_TWICE_NAT)
468 /** \brief Check if NAT session is load-balancing.
470 @return 1 if NAT session is load-balancing
472 #define is_lb_session(s) (s->flags & SNAT_SESSION_FLAG_LOAD_BALANCING)
474 /** \brief Check if NAT session is forwarding bypass.
476 @return 1 if NAT session is load-balancing
478 #define is_fwd_bypass_session(s) (s->flags & SNAT_SESSION_FLAG_FWD_BYPASS)
480 /** \brief Check if NAT session is endpoint dependent.
482 @return 1 if NAT session is endpoint dependent
484 #define is_ed_session(s) (s->flags & SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT)
486 #define nat_interface_is_inside(i) i->flags & NAT_INTERFACE_FLAG_IS_INSIDE
487 #define nat_interface_is_outside(i) i->flags & NAT_INTERFACE_FLAG_IS_OUTSIDE
490 * Why is this here? Because we don't need to touch this layer to
491 * simply reply to an icmp. We need to change id to a unique
492 * value to NAT an echo request/reply.
498 } icmp_echo_header_t;
501 ip_proto_to_snat_proto (u8 ip_proto)
505 snat_proto = (ip_proto == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : snat_proto;
506 snat_proto = (ip_proto == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : snat_proto;
507 snat_proto = (ip_proto == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : snat_proto;
508 snat_proto = (ip_proto == IP_PROTOCOL_ICMP6) ? SNAT_PROTOCOL_ICMP : snat_proto;
514 snat_proto_to_ip_proto (snat_protocol_t snat_proto)
518 ip_proto = (snat_proto == SNAT_PROTOCOL_UDP) ? IP_PROTOCOL_UDP : ip_proto;
519 ip_proto = (snat_proto == SNAT_PROTOCOL_TCP) ? IP_PROTOCOL_TCP : ip_proto;
520 ip_proto = (snat_proto == SNAT_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP : ip_proto;
526 u16 src_port, dst_port;
529 u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
530 u32 thread_index, vlib_buffer_t *b0,
531 ip4_header_t *ip0, u8 *p_proto,
532 snat_session_key_t *p_value,
533 u8 *p_dont_translate, void *d, void *e);
534 u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
535 u32 thread_index, vlib_buffer_t *b0,
536 ip4_header_t *ip0, u8 *p_proto,
537 snat_session_key_t *p_value,
538 u8 *p_dont_translate, void *d, void *e);
539 u32 icmp_match_in2out_det(snat_main_t *sm, vlib_node_runtime_t *node,
540 u32 thread_index, vlib_buffer_t *b0,
541 ip4_header_t *ip0, u8 *p_proto,
542 snat_session_key_t *p_value,
543 u8 *p_dont_translate, void *d, void *e);
544 u32 icmp_match_out2in_fast(snat_main_t *sm, vlib_node_runtime_t *node,
545 u32 thread_index, vlib_buffer_t *b0,
546 ip4_header_t *ip0, u8 *p_proto,
547 snat_session_key_t *p_value,
548 u8 *p_dont_translate, void *d, void *e);
549 u32 icmp_match_out2in_slow(snat_main_t *sm, vlib_node_runtime_t *node,
550 u32 thread_index, vlib_buffer_t *b0,
551 ip4_header_t *ip0, u8 *p_proto,
552 snat_session_key_t *p_value,
553 u8 *p_dont_translate, void *d, void *e);
554 u32 icmp_match_out2in_det(snat_main_t *sm, vlib_node_runtime_t *node,
555 u32 thread_index, vlib_buffer_t *b0,
556 ip4_header_t *ip0, u8 *p_proto,
557 snat_session_key_t *p_value,
558 u8 *p_dont_translate, void *d, void *e);
559 void increment_v4_address(ip4_address_t * a);
560 void snat_add_address(snat_main_t *sm, ip4_address_t *addr, u32 vrf_id,
562 int snat_del_address(snat_main_t *sm, ip4_address_t addr, u8 delete_sm,
564 void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
565 int snat_add_static_mapping(ip4_address_t l_addr, ip4_address_t e_addr,
566 u16 l_port, u16 e_port, u32 vrf_id, int addr_only,
567 u32 sw_if_index, snat_protocol_t proto, int is_add,
568 twice_nat_type_t twice_nat, u8 out2in_only,
570 clib_error_t * snat_api_init(vlib_main_t * vm, snat_main_t * sm);
571 int snat_set_workers (uword * bitmap);
572 int snat_interface_add_del(u32 sw_if_index, u8 is_inside, int is_del);
573 int snat_interface_add_del_output_feature(u32 sw_if_index, u8 is_inside,
575 int snat_add_interface_address(snat_main_t *sm, u32 sw_if_index, int is_del,
577 uword unformat_snat_protocol(unformat_input_t * input, va_list * args);
578 u8 * format_snat_protocol(u8 * s, va_list * args);
579 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
580 snat_protocol_t proto, u32 vrf_id,
581 nat44_lb_addr_port_t *locals, u8 is_add,
582 twice_nat_type_t twice_nat, u8 out2in_only,
584 int nat44_del_session (snat_main_t *sm, ip4_address_t *addr, u16 port,
585 snat_protocol_t proto, u32 vrf_id, int is_in);
586 void nat_free_session_data (snat_main_t * sm, snat_session_t * s,
588 snat_user_t * nat_user_get_or_create (snat_main_t *sm, ip4_address_t *addr,
589 u32 fib_index, u32 thread_index);
590 snat_session_t * nat_session_alloc_or_recycle (snat_main_t *sm, snat_user_t *u,
592 void nat_set_alloc_addr_and_port_mape (u16 psid, u16 psid_offset,
594 void nat_set_alloc_addr_and_port_default (void);
596 static_always_inline u8
597 icmp_is_error_message (icmp46_header_t * icmp)
601 case ICMP4_destination_unreachable:
602 case ICMP4_time_exceeded:
603 case ICMP4_parameter_problem:
604 case ICMP4_source_quench:
606 case ICMP4_alternate_host_address:
612 static_always_inline u8
613 is_interface_addr(snat_main_t *sm, vlib_node_runtime_t *node, u32 sw_if_index0,
616 snat_runtime_t *rt = (snat_runtime_t *) node->runtime_data;
617 ip4_address_t * first_int_addr;
619 if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0))
622 ip4_interface_first_address (sm->ip4_main, sw_if_index0,
623 0 /* just want the address */);
624 rt->cached_sw_if_index = sw_if_index0;
626 rt->cached_ip4_address = first_int_addr->as_u32;
628 rt->cached_ip4_address = 0;
631 if (PREDICT_FALSE(ip4_addr == rt->cached_ip4_address))
638 maximum_sessions_exceeded (snat_main_t *sm, u32 thread_index)
640 if (pool_elts (sm->per_thread_data[thread_index].sessions) >= sm->max_translations)
646 static_always_inline void
647 nat_send_all_to_node(vlib_main_t *vm, u32 *bi_vector,
648 vlib_node_runtime_t *node, vlib_error_t *error, u32 next)
650 u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
653 n_left_from = vec_len(bi_vector);
654 next_index = node->cached_next_index;
655 while (n_left_from > 0) {
656 vlib_get_next_frame(vm, node, next_index, to_next, n_left_to_next);
657 while (n_left_from > 0 && n_left_to_next > 0) {
658 u32 bi0 = to_next[0] = from[0];
663 vlib_buffer_t *p0 = vlib_get_buffer(vm, bi0);
665 vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next,
666 n_left_to_next, bi0, next);
668 vlib_put_next_frame(vm, node, next_index, n_left_to_next);
673 user_session_increment(snat_main_t *sm, snat_user_t *u, u8 is_static)
675 if (u->nsessions + u->nstaticsessions < sm->max_translations_per_user)
678 u->nstaticsessions++;
684 #endif /* __included_snat_h__ */