mirror of
https://github.com/matrix-construct/construct
synced 2024-11-09 03:21:15 +01:00
102 lines
4.3 KiB
C++
102 lines
4.3 KiB
C++
// Matrix Construct
|
|
//
|
|
// Copyright (C) Matrix Construct Developers, Authors & Contributors
|
|
// Copyright (C) 2016-2018 Jason Volk <jason@zemos.net>
|
|
//
|
|
// Permission to use, copy, modify, and/or distribute this software for any
|
|
// purpose with or without fee is hereby granted, provided that the above
|
|
// copyright notice and this permission notice is present in all copies. The
|
|
// full license for this software is available in the LICENSE file.
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_NET_DNS_H
|
|
|
|
/// DNS resolution suite.
|
|
///
|
|
/// Note that at this time these functions must be called on an ircd::ctx to
|
|
/// conduct any queries of the cache.
|
|
///
|
|
namespace ircd::net::dns
|
|
{
|
|
struct opts;
|
|
using records = vector_view<const rfc1035::record *>;
|
|
using callback = std::function<void (const hostport &, const json::array &)>;
|
|
using callback_one = std::function<void (const hostport &, const json::object &)>;
|
|
using callback_ipport = std::function<void (std::exception_ptr, const hostport &, const ipport &)>;
|
|
|
|
extern const struct opts opts_default;
|
|
extern log::log log;
|
|
|
|
// Utilities
|
|
bool is_error(const json::object &rr);
|
|
bool is_error(const json::array &rr);
|
|
bool is_empty(const json::object &rr);
|
|
bool is_empty(const json::array &rr);
|
|
time_t get_ttl(const json::object &rr);
|
|
bool expired(const json::object &rr, const time_t &rr_ts, const time_t &min_ttl);
|
|
bool expired(const json::object &rr, const time_t &rr_ts);
|
|
json::object random_choice(const json::array &);
|
|
string_view make_SRV_key(const mutable_buffer &out, const hostport &, const opts &);
|
|
string_view unmake_SRV_key(const string_view &);
|
|
|
|
// Callback-based interface
|
|
void resolve(const hostport &, const opts &, callback);
|
|
void resolve(const hostport &, const opts &, callback_one); // convenience
|
|
void resolve(const hostport &, const opts &, callback_ipport); // convenience
|
|
}
|
|
|
|
/// DNS resolution options
|
|
struct ircd::net::dns::opts
|
|
{
|
|
/// Specifies the rfc1035 query type. If this is non-zero a query of this
|
|
/// type will be made or an exception will be thrown if it is not possible
|
|
/// to make the query with this type. A zero value means automatic and the
|
|
/// type will deduced and set internally. To translate a string type like
|
|
/// "SRV" to the type integer for this value see ircd/rfc1035.h.
|
|
uint16_t qtype {0};
|
|
|
|
/// Overrides the SRV query to make for this resolution. If empty an
|
|
/// SRV query may still be made from other deductions. This string is
|
|
/// copied at the start of the resolution. It must be a fully qualified
|
|
/// SRV query string: Example: "_matrix._tcp."
|
|
string_view srv;
|
|
|
|
/// Specifies the SRV protocol part when deducing the SRV query to be
|
|
/// made. This is used when the net::hostport.service string is just
|
|
/// the name of the service like "matrix" so we then use this value
|
|
/// to build the protocol part of the SRV query string. It is ignored
|
|
/// if `srv` is set or if no service is specified (thus no SRV query is
|
|
/// made in the first place).
|
|
string_view proto{"tcp"};
|
|
|
|
/// Whether the dns::cache is checked and may respond to the query.
|
|
bool cache_check {true};
|
|
|
|
/// Whether the result of this lookup from the nameserver should be
|
|
/// added to the cache.
|
|
bool cache_result {true};
|
|
|
|
/// When false, nxdomain errors are not treated as exceptions and the
|
|
/// eptr of a callback will not be set. Instead, the returned record
|
|
/// will contain some nulled / empty data and the user is obliged to
|
|
/// know that this is not a real DNS answer but the error's result.
|
|
/// Note: Requires that cache_result is set to true. If not, this value
|
|
/// is ignored and always considered to be set to true; this is because
|
|
/// the returned record is a reference to the cached error.
|
|
bool nxdomain_exceptions {true};
|
|
};
|
|
|
|
/// (internal) DNS cache
|
|
namespace ircd::net::dns::cache
|
|
{
|
|
using closure = std::function<bool (const string_view &, const json::object &)>;
|
|
|
|
string_view make_type(const mutable_buffer &out, const string_view &);
|
|
string_view make_type(const mutable_buffer &out, const uint16_t &);
|
|
|
|
bool for_each(const string_view &type, const closure &); // do not make_type() here
|
|
bool for_each(const hostport &, const opts &, const closure &);
|
|
bool get(const hostport &, const opts &, const callback &);
|
|
bool put(const hostport &, const opts &, const records &);
|
|
bool put(const hostport &, const opts &, const uint &code, const string_view &msg = {});
|
|
}
|