unikernel/duniverse/ocaml-dns/resolver/dns_resolver.mli

@@ -0,0 +1,56 @@
+(* (c) 2018 Hannes Mehnert, all rights reserved *)
+
+type t
+(** The type of a DNS resolver. *)
+
+type feature =
+  [ `Dnssec | `Qname_minimisation | `Opportunistic_tls_authoritative ]
+
+val create : ?record_clients:bool -> ?cache_size:int ->
+  ?ip_protocol:[ `Both | `Ipv4_only | `Ipv6_only ] ->
+  feature list ->
+  int64 -> (int -> string) -> Dns_server.Primary.s -> t
+(** [create ~record_clients ~cache_size ~ip_protocol features now rng primary]
+    creates the value of a resolver, pre-filled with root NS and their IP
+    addresses. If [ip_protocol] is provided, and set to [`V4_only], only IPv4
+    packets will be emitted. If [`V6_only] is set, only IPv6 packets will be
+    emitted. If [`Both] (the default), either IPv4 and IPv6 packets are
+    emitted. If [record_clients] is true (the default), the metrics of
+    the resolver will include the amount of clients.  This keeps a set of
+    Ipaddr.t of all clients around, which may use some memory if it is a public
+    resolver.
+
+    Some features can be specified, whether DNSSec validation should be done,
+    whether query name minimisation should be done, and whether opportunistic
+    encryption using TLS to the authoritative should be done.
+*)
+
+val features : t -> feature list
+
+val handle_buf : t -> Ptime.t -> int64 -> bool -> Dns.proto -> Ipaddr.t ->
+  int -> string ->
+  t * (Dns.proto * Ipaddr.t * int * int32 * string) list
+    * (Dns.proto * Ipaddr.t * string) list
+(** [handle_buf t now ts query_or_reply proto sender source-port buf] handles
+   resolution of [buf], which leads to a new [t], a list of answers to be
+    transmitted (quintuple of protocol, ip address, port, minimum ttl, buffer),
+    and a list of queries (triple of protocol, ip address, buffer). *)
+
+val query_root : t -> int64 -> Dns.proto ->
+  t * (Dns.proto * Ipaddr.t * string)
+(** [query_root t now proto] potentially requests an update of the root
+   zone. Best invoked by a regular timer. *)
+
+val timer : t -> int64 ->
+  t * (Dns.proto * Ipaddr.t * int * int32 * string) list
+    * (Dns.proto * Ipaddr.t * string) list
+(** [timer t now] potentially retransmits DNS requests and/or sends NXDomain
+    answers. *)
+
+val primary_data : t -> Dns_trie.t
+(** [primary_data t] is the DNS trie of the primary. *)
+
+val with_primary_data : t -> Ptime.t -> int64 -> Dns_trie.t -> t * (Ipaddr.t * string list) list
+(** [with_primary_data t now ts data] is a pair [(t', outs)] where [t'] is [t]
+    updated with the [data] DNS trie, and [outs] is the data to send out (if
+    any). *)