diff options
Diffstat (limited to 'src/plugins/snat/nat64.c')
| -rw-r--r-- | src/plugins/snat/nat64.c | 590 |
1 files changed, 590 insertions, 0 deletions
diff --git a/src/plugins/snat/nat64.c b/src/plugins/snat/nat64.c new file mode 100644 index 00000000000..9b6b3c8a5ac --- /dev/null +++ b/src/plugins/snat/nat64.c @@ -0,0 +1,590 @@ +/* + * Copyright (c) 2017 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. + */ +/** + * @file + * @brief NAT64 implementation + */ + +#include <snat/nat64.h> +#include <snat/nat64_db.h> +#include <vnet/fib/ip4_fib.h> + + +nat64_main_t nat64_main; + +/* *INDENT-OFF* */ + +/* Hook up input features */ +VNET_FEATURE_INIT (nat64_in2out, static) = { + .arc_name = "ip6-unicast", + .node_name = "nat64-in2out", + .runs_before = VNET_FEATURES ("ip6-lookup"), +}; +VNET_FEATURE_INIT (nat64_out2in, static) = { + .arc_name = "ip4-unicast", + .node_name = "nat64-out2in", + .runs_before = VNET_FEATURES ("ip4-lookup"), +}; + +/* *INDENT-ON* */ + +clib_error_t * +nat64_init (vlib_main_t * vm) +{ + nat64_main_t *nm = &nat64_main; + clib_error_t *error = 0; + + if (nat64_db_init (&nm->db)) + error = clib_error_return (0, "NAT64 DB init failed"); + + /* set session timeouts to default values */ + nm->udp_timeout = SNAT_UDP_TIMEOUT; + nm->icmp_timeout = SNAT_ICMP_TIMEOUT; + nm->tcp_trans_timeout = SNAT_TCP_TRANSITORY_TIMEOUT; + nm->tcp_est_timeout = SNAT_TCP_ESTABLISHED_TIMEOUT; + nm->tcp_incoming_syn_timeout = SNAT_TCP_INCOMING_SYN; + + return error; +} + +int +nat64_add_del_pool_addr (ip4_address_t * addr, u32 vrf_id, u8 is_add) +{ + nat64_main_t *nm = &nat64_main; + snat_address_t *a = 0; + snat_interface_t *interface; + int i; + + /* Check if address already exists */ + for (i = 0; i < vec_len (nm->addr_pool); i++) + { + if (nm->addr_pool[i].addr.as_u32 == addr->as_u32) + { + a = nm->addr_pool + i; + break; + } + } + + if (is_add) + { + if (a) + return VNET_API_ERROR_VALUE_EXIST; + + vec_add2 (nm->addr_pool, a, 1); + a->addr = *addr; + a->fib_index = ip4_fib_index_from_table_id (vrf_id); +#define _(N, i, n, s) \ + clib_bitmap_alloc (a->busy_##n##_port_bitmap, 65535); + foreach_snat_protocol +#undef _ + } + else + { + if (!a) + return VNET_API_ERROR_NO_SUCH_ENTRY; + +#define _(N, id, n, s) \ + clib_bitmap_free (a->busy_##n##_port_bitmap); + foreach_snat_protocol +#undef _ + vec_del1 (nm->addr_pool, i); + } + + /* Add/del external address to FIB */ + /* *INDENT-OFF* */ + pool_foreach (interface, nm->interfaces, + ({ + if (interface->is_inside) + continue; + + snat_add_del_addr_to_fib (addr, 32, interface->sw_if_index, is_add); + break; + })); + /* *INDENT-ON* */ + + return 0; +} + +void +nat64_pool_addr_walk (nat64_pool_addr_walk_fn_t fn, void *ctx) +{ + nat64_main_t *nm = &nat64_main; + snat_address_t *a = 0; + + /* *INDENT-OFF* */ + vec_foreach (a, nm->addr_pool) + { + if (fn (a, ctx)) + break; + }; + /* *INDENT-ON* */ +} + +int +nat64_add_del_interface (u32 sw_if_index, u8 is_inside, u8 is_add) +{ + nat64_main_t *nm = &nat64_main; + snat_interface_t *interface = 0, *i; + snat_address_t *ap; + const char *feature_name, *arc_name; + + /* Check if address already exists */ + /* *INDENT-OFF* */ + pool_foreach (i, nm->interfaces, + ({ + if (i->sw_if_index == sw_if_index) + { + interface = i; + break; + } + })); + /* *INDENT-ON* */ + + if (is_add) + { + if (interface) + return VNET_API_ERROR_VALUE_EXIST; + + pool_get (nm->interfaces, interface); + interface->sw_if_index = sw_if_index; + interface->is_inside = is_inside; + + } + else + { + if (!interface) + return VNET_API_ERROR_NO_SUCH_ENTRY; + + pool_put (nm->interfaces, interface); + } + + if (!is_inside) + { + /* *INDENT-OFF* */ + vec_foreach (ap, nm->addr_pool) + snat_add_del_addr_to_fib(&ap->addr, 32, sw_if_index, is_add); + /* *INDENT-ON* */ + } + + arc_name = is_inside ? "ip6-unicast" : "ip4-unicast"; + feature_name = is_inside ? "nat64-in2out" : "nat64-out2in"; + + return vnet_feature_enable_disable (arc_name, feature_name, sw_if_index, + is_add, 0, 0); +} + +void +nat64_interfaces_walk (nat64_interface_walk_fn_t fn, void *ctx) +{ + nat64_main_t *nm = &nat64_main; + snat_interface_t *i = 0; + + /* *INDENT-OFF* */ + pool_foreach (i, nm->interfaces, + ({ + if (fn (i, ctx)) + break; + })); + /* *INDENT-ON* */ +} + +int +nat64_alloc_out_addr_and_port (u32 fib_index, snat_protocol_t proto, + ip4_address_t * addr, u16 * port) +{ + nat64_main_t *nm = &nat64_main; + snat_main_t *sm = &snat_main; + int i; + snat_address_t *a; + u32 portnum; + + for (i = 0; i < vec_len (nm->addr_pool); i++) + { + a = nm->addr_pool + i; + switch (proto) + { +#define _(N, j, n, s) \ + case SNAT_PROTOCOL_##N: \ + if (a->busy_##n##_ports < (65535-1024)) \ + { \ + while (1) \ + { \ + portnum = random_u32 (&sm->random_seed); \ + portnum &= 0xFFFF; \ + if (portnum < 1024) \ + continue; \ + if (clib_bitmap_get_no_check (a->busy_##n##_port_bitmap, \ + portnum)) \ + continue; \ + clib_bitmap_set_no_check (a->busy_##n##_port_bitmap, \ + portnum, 1); \ + a->busy_##n##_ports++; \ + *port = portnum; \ + addr->as_u32 = a->addr.as_u32; \ + return 0; \ + } \ + } \ + break; + foreach_snat_protocol +#undef _ + default: + clib_warning ("unknown protocol"); + return 1; + } + + } + /* Totally out of translations to use... */ + //TODO: IPFix + return 1; +} + +void +nat64_free_out_addr_and_port (ip4_address_t * addr, u16 port, + snat_protocol_t proto) +{ + nat64_main_t *nm = &nat64_main; + int i; + snat_address_t *a; + + for (i = 0; i < vec_len (nm->addr_pool); i++) + { + a = nm->addr_pool + i; + if (addr->as_u32 != a->addr.as_u32) + continue; + switch (proto) + { +#define _(N, j, n, s) \ + case SNAT_PROTOCOL_##N: \ + ASSERT (clib_bitmap_get_no_check (a->busy_##n##_port_bitmap, \ + port) == 1); \ + clib_bitmap_set_no_check (a->busy_##n##_port_bitmap, port, 0); \ + a->busy_##n##_ports--; \ + break; + foreach_snat_protocol +#undef _ + default: + clib_warning ("unknown protocol"); + return; + } + break; + } +} + +int +nat64_add_del_static_bib_entry (ip6_address_t * in_addr, + ip4_address_t * out_addr, u16 in_port, + u16 out_port, u8 proto, u32 vrf_id, u8 is_add) +{ + nat64_main_t *nm = &nat64_main; + nat64_db_bib_entry_t *bibe; + u32 fib_index = + fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6, vrf_id); + snat_protocol_t p = ip_proto_to_snat_proto (proto); + ip46_address_t addr; + int i; + snat_address_t *a; + + addr.as_u64[0] = in_addr->as_u64[0]; + addr.as_u64[1] = in_addr->as_u64[1]; + bibe = + nat64_db_bib_entry_find (&nm->db, &addr, clib_host_to_net_u16 (in_port), + p, fib_index, 1); + + if (is_add) + { + if (bibe) + return VNET_API_ERROR_VALUE_EXIST; + + for (i = 0; i < vec_len (nm->addr_pool); i++) + { + a = nm->addr_pool + i; + if (out_addr->as_u32 != a->addr.as_u32) + continue; + switch (p) + { +#define _(N, j, n, s) \ + case SNAT_PROTOCOL_##N: \ + if (clib_bitmap_get_no_check (a->busy_##n##_port_bitmap, \ + out_port)) \ + return VNET_API_ERROR_INVALID_VALUE; \ + clib_bitmap_set_no_check (a->busy_##n##_port_bitmap, \ + out_port, 1); \ + if (out_port > 1024) \ + a->busy_##n##_ports++; \ + break; + foreach_snat_protocol +#undef _ + default: + clib_warning ("unknown protocol"); + return VNET_API_ERROR_INVALID_VALUE_2; + } + break; + } + bibe = + nat64_db_bib_entry_create (&nm->db, in_addr, out_addr, + clib_host_to_net_u16 (in_port), + clib_host_to_net_u16 (out_port), fib_index, + p, 1); + if (!bibe) + return VNET_API_ERROR_UNSPECIFIED; + } + else + { + if (!bibe) + return VNET_API_ERROR_NO_SUCH_ENTRY; + + nat64_free_out_addr_and_port (out_addr, out_port, p); + nat64_db_bib_entry_free (&nm->db, bibe); + } + + return 0; +} + +int +nat64_set_udp_timeout (u32 timeout) +{ + nat64_main_t *nm = &nat64_main; + + if (timeout == 0) + nm->udp_timeout = SNAT_UDP_TIMEOUT; + else if (timeout < SNAT_UDP_TIMEOUT_MIN) + return VNET_API_ERROR_INVALID_VALUE; + else + nm->udp_timeout = timeout; + + return 0; +} + +u32 +nat64_get_udp_timeout (void) +{ + nat64_main_t *nm = &nat64_main; + + return nm->udp_timeout; +} + +int +nat64_set_icmp_timeout (u32 timeout) +{ + nat64_main_t *nm = &nat64_main; + + if (timeout == 0) + nm->icmp_timeout = SNAT_ICMP_TIMEOUT; + else + nm->icmp_timeout = timeout; + + return 0; +} + +u32 +nat64_get_icmp_timeout (void) +{ + nat64_main_t *nm = &nat64_main; + + return nm->icmp_timeout; +} + +int +nat64_set_tcp_timeouts (u32 trans, u32 est, u32 incoming_syn) +{ + nat64_main_t *nm = &nat64_main; + + if (trans == 0) + nm->tcp_trans_timeout = SNAT_TCP_TRANSITORY_TIMEOUT; + else + nm->tcp_trans_timeout = trans; + + if (est == 0) + nm->tcp_est_timeout = SNAT_TCP_ESTABLISHED_TIMEOUT; + else + nm->tcp_est_timeout = est; + + if (incoming_syn == 0) + nm->tcp_incoming_syn_timeout = SNAT_TCP_INCOMING_SYN; + else + nm->tcp_incoming_syn_timeout = incoming_syn; + + return 0; +} + +u32 +nat64_get_tcp_trans_timeout (void) +{ + nat64_main_t *nm = &nat64_main; + + return nm->tcp_trans_timeout; +} + +u32 +nat64_get_tcp_est_timeout (void) +{ + nat64_main_t *nm = &nat64_main; + + return nm->tcp_est_timeout; +} + +u32 +nat64_get_tcp_incoming_syn_timeout (void) +{ + nat64_main_t *nm = &nat64_main; + + return nm->tcp_incoming_syn_timeout; +} + +void +nat64_session_reset_timeout (nat64_db_st_entry_t * ste, vlib_main_t * vm) +{ + nat64_main_t *nm = &nat64_main; + u32 now = (u32) vlib_time_now (vm); + + switch (ste->proto) + { + case SNAT_PROTOCOL_ICMP: + ste->expire = now + nm->icmp_timeout; + return; + case SNAT_PROTOCOL_TCP: + { + switch (ste->tcp_state) + { + case NAT64_TCP_STATE_V4_INIT: + case NAT64_TCP_STATE_V6_INIT: + case NAT64_TCP_STATE_V4_FIN_RCV: + case NAT64_TCP_STATE_V6_FIN_RCV: + case NAT64_TCP_STATE_V6_FIN_V4_FIN_RCV: + case NAT64_TCP_STATE_TRANS: + ste->expire = now + nm->tcp_trans_timeout; + return; + case NAT64_TCP_STATE_ESTABLISHED: + ste->expire = now + nm->tcp_est_timeout; + return; + default: + return; + } + } + case SNAT_PROTOCOL_UDP: + ste->expire = now + nm->udp_timeout; + return; + default: + return; + } +} + +void +nat64_tcp_session_set_state (nat64_db_st_entry_t * ste, tcp_header_t * tcp, + u8 is_ip6) +{ + switch (ste->tcp_state) + { + case NAT64_TCP_STATE_CLOSED: + { + if (tcp->flags & TCP_FLAG_SYN) + { + if (is_ip6) + ste->tcp_state = NAT64_TCP_STATE_V6_INIT; + else + ste->tcp_state = NAT64_TCP_STATE_V4_INIT; + } + return; + } + case NAT64_TCP_STATE_V4_INIT: + { + if (is_ip6 && (tcp->flags & TCP_FLAG_SYN)) + ste->tcp_state = NAT64_TCP_STATE_ESTABLISHED; + return; + } + case NAT64_TCP_STATE_V6_INIT: + { + if (!is_ip6 && (tcp->flags & TCP_FLAG_SYN)) + ste->tcp_state = NAT64_TCP_STATE_ESTABLISHED; + return; + } + case NAT64_TCP_STATE_ESTABLISHED: + { + if (tcp->flags & TCP_FLAG_FIN) + { + if (is_ip6) + ste->tcp_state = NAT64_TCP_STATE_V6_FIN_RCV; + else + ste->tcp_state = NAT64_TCP_STATE_V4_FIN_RCV; + } + else if (tcp->flags & TCP_FLAG_RST) + { + ste->tcp_state = NAT64_TCP_STATE_TRANS; + } + return; + } + case NAT64_TCP_STATE_V4_FIN_RCV: + { + if (is_ip6 && (tcp->flags & TCP_FLAG_FIN)) + ste->tcp_state = NAT64_TCP_STATE_V6_FIN_V4_FIN_RCV; + return; + } + case NAT64_TCP_STATE_V6_FIN_RCV: + { + if (!is_ip6 && (tcp->flags & TCP_FLAG_FIN)) + ste->tcp_state = NAT64_TCP_STATE_V6_FIN_V4_FIN_RCV; + return; + } + case NAT64_TCP_STATE_TRANS: + { + if (!(tcp->flags & TCP_FLAG_RST)) + ste->tcp_state = NAT64_TCP_STATE_ESTABLISHED; + return; + } + default: + return; + } +} + +/** + * @brief The 'nat64-expire-walk' process's main loop. + * + * Check expire time for NAT64 sessions. + */ +static uword +nat64_expire_walk_fn (vlib_main_t * vm, vlib_node_runtime_t * rt, + vlib_frame_t * f) +{ + nat64_main_t *nm = &nat64_main; + + while (1) + { + vlib_process_wait_for_event_or_clock (vm, 10.0); + vlib_process_get_events (vm, NULL); + u32 now = (u32) vlib_time_now (vm); + + nad64_db_st_free_expired (&nm->db, now); + } + + return 0; +} + +static vlib_node_registration_t nat64_expire_walk_node; + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (nat64_expire_walk_node, static) = { + .function = nat64_expire_walk_fn, + .type = VLIB_NODE_TYPE_PROCESS, + .name = "nat64-expire-walk", +}; +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |