-- This file is included with Prosody IM. It has modifications,
-- which are hereby placed in the public domain.
--- public domain 20080404 lua@ztact.com
-
-- todo: quick (default) header generation
-- todo: nxdomain, error handling
local socket = require "socket";
-local ztact = require "util.ztact";
local timer = require "util.timer";
local _, windows = pcall(require, "util.windows");
local coroutine, io, math, string, table =
coroutine, io, math, string, table;
-local ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack =
- ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack;
+local ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack, select, type=
+ ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack, select, type;
+
+local ztact = { -- public domain 20080404 lua@ztact.com
+ get = function(parent, ...)
+ local len = select('#', ...);
+ for i=1,len do
+ parent = parent[select(i, ...)];
+ if parent == nil then break; end
+ end
+ return parent;
+ end;
+ set = function(parent, ...)
+ local len = select('#', ...);
+ local key, value = select(len-1, ...);
+ local cutpoint, cutkey;
+
+ for i=1,len-2 do
+ local key = select (i, ...)
+ local child = parent[key]
+
+ if value == nil then
+ if child == nil then
+ return;
+ elseif next(child, next(child)) then
+ cutpoint = nil; cutkey = nil;
+ elseif cutpoint == nil then
+ cutpoint = parent; cutkey = key;
+ end
+ elseif child == nil then
+ child = {};
+ parent[key] = child;
+ end
+ parent = child
+ end
+ if value == nil and cutpoint then
+ cutpoint[cutkey] = nil;
+ else
+ parent[key] = value;
+ return value;
+ end
+ end;
+};
local get, set = ztact.get, ztact.set;
local default_timeout = 15;
local SRV_tostring;
+local function default_rr_tostring(rr)
+ local rr_val = rr.type and rr[rr.type:lower()];
+ if type(rr_val) ~= "string" then
+ return "<UNKNOWN RDATA TYPE>";
+ end
+ return rr_val;
+end
+
+local special_tostrings = {
+ LOC = resolver.LOC_tostring;
+ MX = function (rr) return string.format('%2i %s', rr.pref, rr.mx); end;
+ SRV = SRV_tostring;
+};
local rr_metatable = {}; -- - - - - - - - - - - - - - - - - - - rr_metatable
function rr_metatable.__tostring(rr)
- local s0 = string.format('%2s %-5s %6i %-28s', rr.class, rr.type, rr.ttl, rr.name);
- local s1 = '';
- if rr.type == 'A' then
- s1 = ' '..rr.a;
- elseif rr.type == 'MX' then
- s1 = string.format(' %2i %s', rr.pref, rr.mx);
- elseif rr.type == 'CNAME' then
- s1 = ' '..rr.cname;
- elseif rr.type == 'LOC' then
- s1 = ' '..resolver.LOC_tostring(rr);
- elseif rr.type == 'NS' then
- s1 = ' '..rr.ns;
- elseif rr.type == 'SRV' then
- s1 = ' '..SRV_tostring(rr);
- elseif rr.type == 'TXT' then
- s1 = ' '..rr.txt;
- else
- s1 = ' <UNKNOWN RDATA TYPE>';
- end
- return s0..s1;
+ local rr_string = (special_tostrings[rr.type] or default_rr_tostring)(rr);
+ return string.format('%2s %-5s %6i %-28s %s', rr.class, rr.type, rr.ttl, rr.name, rr_string);
end
function resolver:adddefaultnameservers() -- - - - - adddefaultnameservers
if is_windows then
- if windows then
+ if windows and windows.get_nameservers then
for _, server in ipairs(windows.get_nameservers()) do
self:addnameserver(server);
end
local sock = self.socket[servernum];
if sock then return sock; end
- sock = socket.udp();
+ local err;
+ sock, err = socket.udp();
+ if not sock then
+ return nil, err;
+ end
if self.socket_wrapper then sock = self.socket_wrapper(sock, self); end
sock:settimeout(0);
-- todo: attempt to use a random port, fallback to 0
--set(self.yielded, co, qclass, qtype, qname, true);
end
- local conn = self:getsocket(o.server)
+ local conn, err = self:getsocket(o.server)
+ if not conn then
+ return nil, err;
+ end
conn:send (o.packet)
if timer and self.timeout then
i = i + 1;
self:servfail(conn);
o.server = self.best_server;
- conn = self:getsocket(o.server);
- conn:send(o.packet);
- return self.timeout;
- else
- -- Tried everything, failed
- self:cancel(qclass, qtype, qname, co, true);
+ conn, err = self:getsocket(o.server);
+ if conn then
+ conn:send(o.packet);
+ return self.timeout;
+ end
end
+ -- Tried everything, failed
+ self:cancel(qclass, qtype, qname, co, true);
end
end)
end
+ return true;
end
function resolver:servfail(sock)
return self:peek(qname, qtype, qclass) or self:query(qname, qtype, qclass);
end
+function resolver:tohostname(ip)
+ return dns.lookup(ip:gsub("(%d+)%.(%d+)%.(%d+)%.(%d+)", "%4.%3.%2.%1.in-addr.arpa."), "PTR");
+end
--print ---------------------------------------------------------------- print
return _resolver:lookup(...);
end
+function dns.tohostname(...)
+ return _resolver:tohostname(...);
+end
+
function dns.purge(...) -- - - - - - - - - - - - - - - - - - - - - - purge
return _resolver:purge(...);
end