diff options
Diffstat (limited to 'src/plugins/nat/nat.h')
| -rw-r--r-- | src/plugins/nat/nat.h | 555 |
1 files changed, 555 insertions, 0 deletions
diff --git a/src/plugins/nat/nat.h b/src/plugins/nat/nat.h new file mode 100644 index 00000000..e53e924f --- /dev/null +++ b/src/plugins/nat/nat.h @@ -0,0 +1,555 @@ + +/* + * nat.h - NAT plugin definitions + * + * Copyright (c) 2016 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#ifndef __included_nat_h__ +#define __included_nat_h__ + +#include <vnet/vnet.h> +#include <vnet/ip/ip.h> +#include <vnet/ethernet/ethernet.h> +#include <vnet/ip/icmp46_packet.h> +#include <vnet/api_errno.h> +#include <vppinfra/bihash_8_8.h> +#include <vppinfra/bihash_16_8.h> +#include <vppinfra/dlist.h> +#include <vppinfra/error.h> +#include <vlibapi/api.h> + + +#define SNAT_UDP_TIMEOUT 300 +#define SNAT_UDP_TIMEOUT_MIN 120 +#define SNAT_TCP_TRANSITORY_TIMEOUT 240 +#define SNAT_TCP_ESTABLISHED_TIMEOUT 7440 +#define SNAT_TCP_INCOMING_SYN 6 +#define SNAT_ICMP_TIMEOUT 60 + +#define SNAT_FLAG_HAIRPINNING (1 << 0) + +/* Key */ +typedef struct { + union + { + struct + { + ip4_address_t addr; + u16 port; + u16 protocol:3, + fib_index:13; + }; + u64 as_u64; + }; +} snat_session_key_t; + +typedef struct { + union + { + struct + { + ip4_address_t l_addr; + ip4_address_t r_addr; + u32 fib_index; + u16 l_port; + u8 proto; + u8 rsvd; + }; + u64 as_u64[2]; + }; +} nat_ed_ses_key_t; + +typedef struct { + union + { + struct + { + ip4_address_t ext_host_addr; + u16 ext_host_port; + u16 out_port; + }; + u64 as_u64; + }; +} snat_det_out_key_t; + +typedef struct { + union + { + struct + { + ip4_address_t addr; + u32 fib_index; + }; + u64 as_u64; + }; +} snat_user_key_t; + + +#define foreach_snat_protocol \ + _(UDP, 0, udp, "udp") \ + _(TCP, 1, tcp, "tcp") \ + _(ICMP, 2, icmp, "icmp") + +typedef enum { +#define _(N, i, n, s) SNAT_PROTOCOL_##N = i, + foreach_snat_protocol +#undef _ +} snat_protocol_t; + + +#define foreach_snat_session_state \ + _(0, UNKNOWN, "unknown") \ + _(1, UDP_ACTIVE, "udp-active") \ + _(2, TCP_SYN_SENT, "tcp-syn-sent") \ + _(3, TCP_ESTABLISHED, "tcp-established") \ + _(4, TCP_FIN_WAIT, "tcp-fin-wait") \ + _(5, TCP_CLOSE_WAIT, "tcp-close-wait") \ + _(6, TCP_LAST_ACK, "tcp-last-ack") \ + _(7, ICMP_ACTIVE, "icmp-active") + +typedef enum { +#define _(v, N, s) SNAT_SESSION_##N = v, + foreach_snat_session_state +#undef _ +} snat_session_state_t; + + +#define SNAT_SESSION_FLAG_STATIC_MAPPING 1 +#define SNAT_SESSION_FLAG_UNKNOWN_PROTO 2 +#define SNAT_SESSION_FLAG_LOAD_BALANCING 4 + +typedef CLIB_PACKED(struct { + snat_session_key_t out2in; /* 0-15 */ + + snat_session_key_t in2out; /* 16-31 */ + + u32 flags; /* 32-35 */ + + /* per-user translations */ + u32 per_user_index; /* 36-39 */ + + u32 per_user_list_head_index; /* 40-43 */ + + /* Last heard timer */ + f64 last_heard; /* 44-51 */ + + u64 total_bytes; /* 52-59 */ + + u32 total_pkts; /* 60-63 */ + + /* Outside address */ + u32 outside_address_index; /* 64-67 */ + + /* External host address */ + ip4_address_t ext_host_addr; /* 68-71 */ + +}) snat_session_t; + + +typedef struct { + ip4_address_t addr; + u32 fib_index; + u32 sessions_per_user_list_head_index; + u32 nsessions; + u32 nstaticsessions; +} snat_user_t; + +typedef struct { + ip4_address_t addr; + u32 fib_index; +#define _(N, i, n, s) \ + u16 busy_##n##_ports; \ + u16 * busy_##n##_ports_per_thread; \ + uword * busy_##n##_port_bitmap; + foreach_snat_protocol +#undef _ +} snat_address_t; + +typedef struct { + u16 in_port; + snat_det_out_key_t out; + u8 state; + u32 expire; +} snat_det_session_t; + +typedef struct { + ip4_address_t in_addr; + u8 in_plen; + ip4_address_t out_addr; + u8 out_plen; + u32 sharing_ratio; + u16 ports_per_host; + u32 ses_num; + /* vector of sessions */ + snat_det_session_t * sessions; +} snat_det_map_t; + +typedef struct { + ip4_address_t addr; + u16 port; + u8 probability; + u8 prefix; +} nat44_lb_addr_port_t; + +typedef struct { + ip4_address_t local_addr; + ip4_address_t external_addr; + u16 local_port; + u16 external_port; + u8 addr_only; + u32 vrf_id; + u32 fib_index; + snat_protocol_t proto; + u32 worker_index; + nat44_lb_addr_port_t *locals; +} snat_static_mapping_t; + +typedef struct { + u32 sw_if_index; + u8 is_inside; +} snat_interface_t; + +typedef struct { + ip4_address_t l_addr; + u16 l_port; + u16 e_port; + u32 sw_if_index; + u32 vrf_id; + snat_protocol_t proto; + int addr_only; + int is_add; +} snat_static_map_resolve_t; + +typedef struct { + /* Main lookup tables */ + clib_bihash_8_8_t out2in; + clib_bihash_8_8_t in2out; + + /* Find-a-user => src address lookup */ + clib_bihash_8_8_t user_hash; + + /* User pool */ + snat_user_t * users; + + /* Session pool */ + snat_session_t * sessions; + + /* Pool of doubly-linked list elements */ + dlist_elt_t * list_pool; + + u32 snat_thread_index; +} snat_main_per_thread_data_t; + +struct snat_main_s; + +typedef u32 snat_icmp_match_function_t (struct snat_main_s *sm, + vlib_node_runtime_t *node, + u32 thread_index, + vlib_buffer_t *b0, + ip4_header_t *ip0, + u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, + void *d, + void *e); + +typedef u32 (snat_get_worker_function_t) (ip4_header_t * ip, u32 rx_fib_index); + +typedef struct snat_main_s { + /* Endpoint address dependent sessions lookup tables */ + clib_bihash_16_8_t out2in_ed; + clib_bihash_16_8_t in2out_ed; + + snat_icmp_match_function_t * icmp_match_in2out_cb; + snat_icmp_match_function_t * icmp_match_out2in_cb; + + u32 num_workers; + u32 first_worker_index; + u32 next_worker; + u32 * workers; + snat_get_worker_function_t * worker_in2out_cb; + snat_get_worker_function_t * worker_out2in_cb; + u16 port_per_thread; + u32 num_snat_thread; + + /* Per thread data */ + snat_main_per_thread_data_t * per_thread_data; + + /* Find a static mapping by local */ + clib_bihash_8_8_t static_mapping_by_local; + + /* Find a static mapping by external */ + clib_bihash_8_8_t static_mapping_by_external; + + /* Static mapping pool */ + snat_static_mapping_t * static_mappings; + + /* Interface pool */ + snat_interface_t * interfaces; + snat_interface_t * output_feature_interfaces; + + /* Vector of outside addresses */ + snat_address_t * addresses; + + /* sw_if_indices whose intfc addresses should be auto-added */ + u32 * auto_add_sw_if_indices; + + /* vector of interface address static mappings to resolve. */ + snat_static_map_resolve_t *to_resolve; + + /* Randomize port allocation order */ + u32 random_seed; + + /* Worker handoff index */ + u32 fq_in2out_index; + u32 fq_in2out_output_index; + u32 fq_out2in_index; + + /* in2out and out2in node index */ + u32 in2out_node_index; + u32 in2out_output_node_index; + u32 out2in_node_index; + + /* Deterministic NAT */ + snat_det_map_t * det_maps; + + /* Config parameters */ + u8 static_mapping_only; + u8 static_mapping_connection_tracking; + u8 deterministic; + u32 translation_buckets; + u32 translation_memory_size; + u32 max_translations; + u32 user_buckets; + u32 user_memory_size; + u32 max_translations_per_user; + u32 outside_vrf_id; + u32 outside_fib_index; + u32 inside_vrf_id; + u32 inside_fib_index; + + /* tenant VRF aware address pool activation flag */ + u8 vrf_mode; + + /* values of various timeouts */ + u32 udp_timeout; + u32 tcp_established_timeout; + u32 tcp_transitory_timeout; + u32 icmp_timeout; + + /* API message ID base */ + u16 msg_id_base; + + /* convenience */ + vlib_main_t * vlib_main; + vnet_main_t * vnet_main; + ip4_main_t * ip4_main; + ip_lookup_main_t * ip4_lookup_main; + api_main_t * api_main; +} snat_main_t; + +extern snat_main_t snat_main; +extern vlib_node_registration_t snat_in2out_node; +extern vlib_node_registration_t snat_in2out_output_node; +extern vlib_node_registration_t snat_out2in_node; +extern vlib_node_registration_t snat_in2out_fast_node; +extern vlib_node_registration_t snat_out2in_fast_node; +extern vlib_node_registration_t snat_in2out_worker_handoff_node; +extern vlib_node_registration_t snat_in2out_output_worker_handoff_node; +extern vlib_node_registration_t snat_out2in_worker_handoff_node; +extern vlib_node_registration_t snat_det_in2out_node; +extern vlib_node_registration_t snat_det_out2in_node; +extern vlib_node_registration_t snat_hairpin_dst_node; +extern vlib_node_registration_t snat_hairpin_src_node; + +void snat_free_outside_address_and_port (snat_main_t * sm, + u32 thread_index, + snat_session_key_t * k, + u32 address_index); + +int snat_alloc_outside_address_and_port (snat_main_t * sm, + u32 fib_index, + u32 thread_index, + snat_session_key_t * k, + u32 * address_indexp); + +int snat_static_mapping_match (snat_main_t * sm, + snat_session_key_t match, + snat_session_key_t * mapping, + u8 by_external, + u8 *is_addr_only); + +void snat_add_del_addr_to_fib (ip4_address_t * addr, + u8 p_len, + u32 sw_if_index, + int is_add); + +format_function_t format_snat_user; + +typedef struct { + u32 cached_sw_if_index; + u32 cached_ip4_address; +} snat_runtime_t; + +/** \brief Check if SNAT session is created from static mapping. + @param s SNAT session + @return 1 if SNAT session is created from static mapping otherwise 0 +*/ +#define snat_is_session_static(s) s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING + +/** \brief Check if SNAT session for unknown protocol. + @param s SNAT session + @return 1 if SNAT session for unknown protocol otherwise 0 +*/ +#define snat_is_unk_proto_session(s) s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO + +/* + * Why is this here? Because we don't need to touch this layer to + * simply reply to an icmp. We need to change id to a unique + * value to NAT an echo request/reply. + */ + +typedef struct { + u16 identifier; + u16 sequence; +} icmp_echo_header_t; + +always_inline u32 +ip_proto_to_snat_proto (u8 ip_proto) +{ + u32 snat_proto = ~0; + + snat_proto = (ip_proto == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : snat_proto; + snat_proto = (ip_proto == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : snat_proto; + snat_proto = (ip_proto == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : snat_proto; + snat_proto = (ip_proto == IP_PROTOCOL_ICMP6) ? SNAT_PROTOCOL_ICMP : snat_proto; + + return snat_proto; +} + +always_inline u8 +snat_proto_to_ip_proto (snat_protocol_t snat_proto) +{ + u8 ip_proto = ~0; + + ip_proto = (snat_proto == SNAT_PROTOCOL_UDP) ? IP_PROTOCOL_UDP : ip_proto; + ip_proto = (snat_proto == SNAT_PROTOCOL_TCP) ? IP_PROTOCOL_TCP : ip_proto; + ip_proto = (snat_proto == SNAT_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP : ip_proto; + + return ip_proto; +} + +typedef struct { + u16 src_port, dst_port; +} tcp_udp_header_t; + +u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node, + u32 thread_index, vlib_buffer_t *b0, + ip4_header_t *ip0, u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, void *d, void *e); +u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node, + u32 thread_index, vlib_buffer_t *b0, + ip4_header_t *ip0, u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, void *d, void *e); +u32 icmp_match_in2out_det(snat_main_t *sm, vlib_node_runtime_t *node, + u32 thread_index, vlib_buffer_t *b0, + ip4_header_t *ip0, u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, void *d, void *e); +u32 icmp_match_out2in_fast(snat_main_t *sm, vlib_node_runtime_t *node, + u32 thread_index, vlib_buffer_t *b0, + ip4_header_t *ip0, u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, void *d, void *e); +u32 icmp_match_out2in_slow(snat_main_t *sm, vlib_node_runtime_t *node, + u32 thread_index, vlib_buffer_t *b0, + ip4_header_t *ip0, u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, void *d, void *e); +u32 icmp_match_out2in_det(snat_main_t *sm, vlib_node_runtime_t *node, + u32 thread_index, vlib_buffer_t *b0, + ip4_header_t *ip0, u8 *p_proto, + snat_session_key_t *p_value, + u8 *p_dont_translate, void *d, void *e); +void increment_v4_address(ip4_address_t * a); +void snat_add_address(snat_main_t *sm, ip4_address_t *addr, u32 vrf_id); +int snat_del_address(snat_main_t *sm, ip4_address_t addr, u8 delete_sm); +int snat_add_static_mapping(ip4_address_t l_addr, ip4_address_t e_addr, + u16 l_port, u16 e_port, u32 vrf_id, int addr_only, + u32 sw_if_index, snat_protocol_t proto, int is_add); +clib_error_t * snat_api_init(vlib_main_t * vm, snat_main_t * sm); +int snat_set_workers (uword * bitmap); +int snat_interface_add_del(u32 sw_if_index, u8 is_inside, int is_del); +int snat_interface_add_del_output_feature(u32 sw_if_index, u8 is_inside, + int is_del); +int snat_add_interface_address(snat_main_t *sm, u32 sw_if_index, int is_del); +uword unformat_snat_protocol(unformat_input_t * input, va_list * args); +u8 * format_snat_protocol(u8 * s, va_list * args); +int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port, + snat_protocol_t proto, u32 vrf_id, + nat44_lb_addr_port_t *locals, u8 is_add); + +static_always_inline u8 +icmp_is_error_message (icmp46_header_t * icmp) +{ + switch(icmp->type) + { + case ICMP4_destination_unreachable: + case ICMP4_time_exceeded: + case ICMP4_parameter_problem: + case ICMP4_source_quench: + case ICMP4_redirect: + case ICMP4_alternate_host_address: + return 1; + } + return 0; +} + +static_always_inline u8 +is_interface_addr(snat_main_t *sm, vlib_node_runtime_t *node, u32 sw_if_index0, + u32 ip4_addr) +{ + snat_runtime_t *rt = (snat_runtime_t *) node->runtime_data; + ip4_address_t * first_int_addr; + + if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) + { + first_int_addr = + ip4_interface_first_address (sm->ip4_main, sw_if_index0, + 0 /* just want the address */); + rt->cached_sw_if_index = sw_if_index0; + if (first_int_addr) + rt->cached_ip4_address = first_int_addr->as_u32; + else + rt->cached_ip4_address = 0; + } + + if (PREDICT_FALSE(ip4_addr == rt->cached_ip4_address)) + return 1; + else + return 0; +} + +always_inline u8 +maximum_sessions_exceeded (snat_main_t *sm, u32 thread_index) +{ + if (pool_elts (sm->per_thread_data[thread_index].sessions) >= sm->max_translations) + return 1; + + return 0; +} + +#endif /* __included_nat_h__ */ |