diff options
Diffstat (limited to 'net/unbound.lua')
| -rw-r--r-- | net/unbound.lua | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/net/unbound.lua b/net/unbound.lua new file mode 100644 index 00000000..df26cd36 --- /dev/null +++ b/net/unbound.lua @@ -0,0 +1,245 @@ +-- libunbound based net.adns replacement for Prosody IM +-- Copyright (C) 2013-2015 Kim Alvefur +-- +-- This file is MIT licensed. +-- +-- luacheck: ignore prosody + +local setmetatable = setmetatable; +local tostring = tostring; +local t_concat = table.concat; +local s_format = string.format; +local s_lower = string.lower; +local s_upper = string.upper; +local noop = function() end; +local zero = function() return 0 end; +local truop = function() return true; end; + +local log = require "util.logger".init("unbound"); +local net_server = require "net.server"; +local libunbound = require"lunbound"; +local have_promise, promise = pcall(require, "util.promise"); + +local gettime = require"socket".gettime; +local dns_utils = require"util.dns"; +local classes, types, errors = dns_utils.classes, dns_utils.types, dns_utils.errors; +local parsers = dns_utils.parsers; + +local function add_defaults(conf) + if conf then + for option, default in pairs(libunbound.config) do + if conf[option] == nil then + conf[option] = default; + end + end + end + return conf; +end + +local unbound_config; +if prosody then + local config = require"core.configmanager"; + unbound_config = add_defaults(config.get("*", "unbound")); + prosody.events.add_handler("config-reloaded", function() + unbound_config = add_defaults(config.get("*", "unbound")); + end); +end +-- Note: libunbound will default to using root hints if resolvconf is unset + +local function connect_server(unbound, server) + if server.watchfd then + return server.watchfd(unbound, function () + unbound:process() + end); + elseif server.event and server.addevent then + local EV_READ = server.event.EV_READ; + local function event_callback() + unbound:process(); + return EV_READ; + end + return server.addevent(unbound:getfd(), EV_READ, event_callback) + elseif server.wrapclient then + local conn = { + getfd = function() + return unbound:getfd(); + end, + + send = zero, + receive = noop, + settimeout = noop, + close = truop, + } + + local function process() + unbound:process(); + end + local listener = { + onincoming = process, + + onconnect = noop, + ondisconnect = noop, + onreadtimeout = truop, + }; + return server.wrapclient(conn, "dns", 0, listener, "*a" ); + end +end + +local unbound = libunbound.new(unbound_config); + +local server_conn = connect_server(unbound, net_server); + +local answer_mt = { + __tostring = function(self) + if self._string then return self._string end + local h = s_format("Status: %s", errors[self.status]); + if self.secure then + h = h .. ", Secure"; + elseif self.bogus then + h = h .. s_format(", Bogus: %s", self.bogus); + end + local t = { h }; + for i = 1, #self do + t[i+1]=self.qname.."\t"..classes[self.qclass].."\t"..types[self.qtype].."\t"..tostring(self[i]); + end + local _string = t_concat(t, "\n"); + self._string = _string; + return _string; + end; +}; + +local waiting_queries = {}; + +local function prep_answer(a) + if not a then return end + local status = errors[a.rcode]; + local qclass = classes[a.qclass]; + local qtype = types[a.qtype]; + a.status, a.class, a.type = status, qclass, qtype; + + local t = s_lower(qtype); + local rr_mt = { __index = a, __tostring = function(self) return tostring(self[t]) end }; + local parser = parsers[qtype]; + for i = 1, #a do + if a.bogus then + -- Discard bogus data + a[i] = nil; + else + a[i] = setmetatable({[t] = parser(a[i])}, rr_mt); + end + end + return setmetatable(a, answer_mt); +end + +local function lookup(callback, qname, qtype, qclass) + qtype = qtype and s_upper(qtype) or "A"; + qclass = qclass and s_upper(qclass) or "IN"; + local ntype, nclass = types[qtype], classes[qclass]; + local startedat = gettime(); + local ret; + local function callback_wrapper(a, err) + local gotdataat = gettime(); + waiting_queries[ret] = nil; + if a then + prep_answer(a); + log("debug", "Results for %s %s %s: %s (%s, %f sec)", qname, qclass, qtype, a.rcode == 0 and (#a .. " items") or a.status, + a.secure and "Secure" or a.bogus or "Insecure", gotdataat - startedat); -- Insecure as in unsigned + else + log("error", "Results for %s %s %s: %s", qname, qclass, qtype, tostring(err)); + end + local ok, cerr = pcall(callback, a, err); + if not ok then log("error", "Error in callback: %s", cerr); end + end + log("debug", "Resolve %s %s %s", qname, qclass, qtype); + local err; + ret, err = unbound:resolve_async(callback_wrapper, qname, ntype, nclass); + if ret then + waiting_queries[ret] = callback; + else + log("warn", err); + end + return ret, err; +end + +local function lookup_sync(qname, qtype, qclass) + qtype = qtype and s_upper(qtype) or "A"; + qclass = qclass and s_upper(qclass) or "IN"; + local ntype, nclass = types[qtype], classes[qclass]; + local a, err = unbound:resolve(qname, ntype, nclass); + if not a then return a, err; end + return prep_answer(a); +end + +local function cancel(id) + local cb = waiting_queries[id]; + unbound:cancel(id); + if cb then + cb(nil, "canceled"); + waiting_queries[id] = nil; + end + return true; +end + +-- Reinitiate libunbound context, drops cache +local function purge() + for id in pairs(waiting_queries) do cancel(id); end + if server_conn then server_conn:close(); end + unbound = libunbound.new(unbound_config); + server_conn = connect_server(unbound, net_server); + return true; +end + +local function not_implemented() + error "not implemented"; +end +-- Public API +local _M = { + lookup = lookup; + cancel = cancel; + new_async_socket = not_implemented; + dns = { + lookup = lookup_sync; + cancel = cancel; + cache = noop; + socket_wrapper_set = noop; + settimeout = noop; + query = noop; + purge = purge; + random = noop; + peek = noop; + + types = types; + classes = classes; + }; +}; + +local lookup_promise; +if have_promise then + function lookup_promise(_, qname, qtype, qclass) + return promise.new(function (resolve, reject) + local function callback(answer, err) + if err then + return reject(err); + else + return resolve(answer); + end + end + local ret, err = lookup(callback, qname, qtype, qclass) + if not ret then reject(err); end + end); + end +end + +local wrapper = { + lookup = function (_, callback, qname, qtype, qclass) + return lookup(callback, qname, qtype, qclass) + end; + lookup_promise = lookup_promise; + _resolver = { + settimeout = function () end; + closeall = function () end; + }; +} + +function _M.resolver() return wrapper; end + +return _M; |