From 34af0ccf5cf27d8a72119626d2d009222e4ff0a6 Mon Sep 17 00:00:00 2001 From: Dave Barach Date: Wed, 21 Aug 2019 19:23:00 -0400 Subject: dns: make the dns name resolver a plugin Type: refactor Signed-off-by: Dave Barach Change-Id: I823c2cd307a4613653a2d20f564dda062d4da31b --- src/plugins/dns/dns.h | 226 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 226 insertions(+) create mode 100644 src/plugins/dns/dns.h (limited to 'src/plugins/dns/dns.h') diff --git a/src/plugins/dns/dns.h b/src/plugins/dns/dns.h new file mode 100644 index 00000000000..0a3f7a935cb --- /dev/null +++ b/src/plugins/dns/dns.h @@ -0,0 +1,226 @@ +/* + * 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. + */ + +#ifndef included_dns_h +#define included_dns_h + +#include +#include +#include + +#include +#include +#include +#include +#include + +typedef struct +{ + u32 request_type; + u32 client_index; + u32 client_context; + u8 is_ip6; + u16 dst_port; + u16 id; + u16 pad; + u8 dst_address[16]; + u8 *name; +} dns_pending_request_t; + +typedef enum +{ + DNS_API_PENDING_NAME_TO_IP = 1, + DNS_API_PENDING_IP_TO_NAME, + DNS_PEER_PENDING_NAME_TO_IP, + DNS_PEER_PENDING_IP_TO_NAME, +} dns_pending_request_type_t; + +typedef struct +{ + /** flags */ + volatile u8 flags; + + /** The name in "normal human being" notation, e.g. www.foobar.com */ + u8 *name; + + /** For CNAME records, the "next name" to resolve */ + u8 *cname; + + /** Expiration time */ + f64 expiration_time; + + /** Cached dns request, for sending retries */ + u8 *dns_request; + + /** Retry parameters */ + int retry_count; + int server_rotor; + int server_af; + int server_fails; + f64 retry_timer; + + /** Cached dns response */ + u8 *dns_response; + + /** Clients / peers awaiting responses */ + dns_pending_request_t *pending_requests; +} dns_cache_entry_t; + +#define DNS_CACHE_ENTRY_FLAG_VALID (1<<0) /**< we have Actual Data */ +#define DNS_CACHE_ENTRY_FLAG_STATIC (1<<1) /**< static entry */ +#define DNS_CACHE_ENTRY_FLAG_CNAME (1<<2) /**< CNAME (indirect) entry */ + +#define DNS_RETRIES_PER_SERVER 3 + +#define DNS_RESOLVER_EVENT_RESOLVED 1 +#define DNS_RESOLVER_EVENT_PENDING 2 + + +typedef struct +{ + /** Pool of cache entries */ + dns_cache_entry_t *entries; + + /** Pool indices of unresolved entries */ + u32 *unresolved_entries; + + /** Find cached record by name */ + uword *cache_entry_by_name; + clib_spinlock_t cache_lock; + + /** enable / disable flag */ + int is_enabled; + + /** udp port registration complete */ + int udp_ports_registered; + + /** upstream name servers, e.g. 8.8.8.8 */ + ip4_address_t *ip4_name_servers; + ip6_address_t *ip6_name_servers; + + /** resolver process node index */ + u32 resolver_process_node_index; + + /** config parameters */ + u32 name_cache_size; + u32 max_ttl_in_seconds; + u32 random_seed; + + /** message-ID base */ + u16 msg_id_base; + + /* convenience */ + vlib_main_t *vlib_main; + vnet_main_t *vnet_main; + api_main_t *api_main; +} dns_main_t; + +extern dns_main_t dns_main; + +extern vlib_node_registration_t dns46_reply_node; +extern vlib_node_registration_t dns4_request_node; +extern vlib_node_registration_t dns6_request_node; + +#define foreach_dns46_request_error \ +_(NONE, "No error") \ +_(UNIMPLEMENTED, "Unimplemented") \ +_(PROCESSED, "DNS request pkts processed") \ +_(IP_OPTIONS, "DNS pkts with ip options (dropped)") \ +_(BAD_REQUEST, "DNS pkts with serious discrepanices (dropped)") \ +_(TOO_MANY_REQUESTS, "DNS pkts asking too many questions") \ +_(RESOLUTION_REQUIRED, "DNS pkts pending upstream name resolution") + +typedef enum +{ +#define _(sym,str) DNS46_REQUEST_ERROR_##sym, + foreach_dns46_request_error +#undef _ + DNS46_REQUEST_N_ERROR, +} dns46_request_error_t; + +#define foreach_dns46_reply_error \ +_(DISABLED, "DNS pkts punted (feature disabled)") \ +_(PROCESSED, "DNS reply pkts processed") \ +_(NO_ELT, "No DNS pool element") \ +_(FORMAT_ERROR, "DNS format errors") \ +_(TEST_DROP, "DNS reply pkt dropped for test purposes") \ +_(MULTIPLE_REPLY, "DNS multiple reply packets") \ +_(NO_UNRESOLVED_ENTRY, "No unresolved entry for pkt") + +typedef enum +{ +#define _(sym,str) DNS46_REPLY_ERROR_##sym, + foreach_dns46_reply_error +#undef _ + DNS46_REPLY_N_ERROR, +} dns46_reply_error_t; + +void vnet_send_dns_request (dns_main_t * dm, dns_cache_entry_t * ep); +int +vnet_dns_cname_indirection_nolock (dns_main_t * dm, u32 ep_index, u8 * reply); + +int vnet_dns_delete_entry_by_index_nolock (dns_main_t * dm, u32 index); + +int +vnet_dns_resolve_name (dns_main_t * dm, u8 * name, dns_pending_request_t * t, + dns_cache_entry_t ** retp); + +void +vnet_dns_send_dns6_request (dns_main_t * dm, + dns_cache_entry_t * ep, ip6_address_t * server); +void +vnet_dns_send_dns4_request (dns_main_t * dm, + dns_cache_entry_t * ep, ip4_address_t * server); + +void vnet_send_dns4_reply (dns_main_t * dm, dns_pending_request_t * t, + dns_cache_entry_t * ep, vlib_buffer_t * b0); + +void vnet_send_dns6_reply (dns_main_t * dm, dns_pending_request_t * t, + dns_cache_entry_t * ep, vlib_buffer_t * b0); + +u8 *vnet_dns_labels_to_name (u8 * label, u8 * full_text, + u8 ** parse_from_here); + +void vnet_dns_create_resolver_process (dns_main_t * dm); + +format_function_t format_dns_reply; + +static inline void +dns_cache_lock (dns_main_t * dm) +{ + if (dm->cache_lock) + { + clib_spinlock_lock (&dm->cache_lock); + } +} + +static inline void +dns_cache_unlock (dns_main_t * dm) +{ + if (dm->cache_lock) + { + clib_spinlock_unlock (&dm->cache_lock); + } +} + +#endif /* included_dns_h */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ -- cgit 1.2.3-korg