net.dns: remove unused one-letter loop variables [luacheck]

[prosody.git] / net / dns.lua

diff --git a/net/dns.lua b/net/dns.lua
index 13417ceeaa368a34b7a35fb7e6bea5f81ef1c077..4a35fc1be79640660c374d1239910ec8bb253f08 100644 (file)
--- a/net/dns.lua
+++ b/net/dns.lua
@@ -14,6 +14,7 @@
 
 local socket = require "socket";
 local timer = require "util.timer";
+local new_ip = require "util.ip".new_ip;
 
 local _, windows = pcall(require, "util.windows");
 local is_windows = (_ and windows) or os.getenv("WINDIR");
@@ -21,8 +22,8 @@ local is_windows = (_ and windows) or os.getenv("WINDIR");
 local coroutine, io, math, string, table =
       coroutine, io, math, string, table;
 
-local ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack, select, type=
-      ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack, select, type;
+local ipairs, next, pairs, print, setmetatable, tostring, assert, error, select, type, unpack=
+      ipairs, next, pairs, print, setmetatable, tostring, assert, error, select, type, table.unpack or unpack;
 
 local ztact = { -- public domain 20080404 lua@ztact.com
        get = function(parent, ...)
@@ -70,8 +71,8 @@ local get, set = ztact.get, ztact.set;
 local default_timeout = 15;
 
 -------------------------------------------------- module dns
-module('dns')
-local dns = _M;
+local _ENV = nil;
+local dns = {};
 
 
 -- dns type & class codes ------------------------------ dns type & class codes
@@ -189,7 +190,7 @@ end
 local rrs_metatable = {};    -- - - - - - - - - - - - - - - - - -  rrs_metatable
 function rrs_metatable.__tostring(rrs)
        local t = {};
-       for i,rr in ipairs(rrs) do
+       for _, rr in ipairs(rrs) do
                append(t, tostring(rr)..'\n');
        end
        return table.concat(t);
@@ -212,20 +213,11 @@ function cache_metatable.__tostring(cache)
 end
 
 
-function resolver:new()    -- - - - - - - - - - - - - - - - - - - - - resolver
-       local r = { active = {}, cache = {}, unsorted = {} };
-       setmetatable(r, resolver);
-       setmetatable(r.cache, cache_metatable);
-       setmetatable(r.unsorted, { __mode = 'kv' });
-       return r;
-end
-
-
 -- packet layer -------------------------------------------------- packet layer
 
 
 function dns.random(...)    -- - - - - - - - - - - - - - - - - - -  dns.random
-       math.randomseed(math.floor(10000*socket.gettime()) % 0x100000000);
+       math.randomseed(math.floor(10000*socket.gettime()) % 0x80000000);
        dns.random = math.random;
        return dns.random(...);
 end
@@ -599,11 +591,12 @@ function resolver:adddefaultnameservers()    -- - - - -  adddefaultnameservers
                if resolv_conf then
                        for line in resolv_conf:lines() do
                                line = line:gsub("#.*$", "")
-                                       :match('^%s*nameserver%s+(.*)%s*$');
+                                       :match('^%s*nameserver%s+([%x:%.]*%%?%S*)%s*$');
                                if line then
-                                       line:gsub("%f[%d.](%d+%.%d+%.%d+%.%d+)%f[^%d.]", function (address)
-                                               self:addnameserver(address)
-                                       end);
+                                       local ip = new_ip(line);
+                                       if ip then
+                                               self:addnameserver(ip.addr);
+                                       end
                                end
                        end
                end
@@ -623,7 +616,12 @@ function resolver:getsocket(servernum)    -- - - - - - - - - - - - - getsocket
        if sock then return sock; end
 
        local ok, err;
-       sock, err = socket.udp();
+       local peer = self.server[servernum];
+       if peer:find(":") then
+               sock, err = socket.udp6();
+       else
+               sock, err = (socket.udp4 or socket.udp)();
+       end
        if sock and self.socket_wrapper then sock, err = self.socket_wrapper(sock, self); end
        if not sock then
                return nil, err;
@@ -636,7 +634,7 @@ function resolver:getsocket(servernum)    -- - - - - - - - - - - - - getsocket
        -- if so, try the next server
        ok, err = sock:setsockname('*', 0);
        if not ok then return self:servfail(sock, err); end
-       ok, err = sock:setpeername(self.server[servernum], 53);
+       ok, err = sock:setpeername(peer, 53);
        if not ok then return self:servfail(sock, err); end
        return sock;
 end
@@ -694,15 +692,20 @@ local function comp_mx(a, b)    -- - - - - - - - - - - - - - - - - - - comp_mx
 end
 
 
-function resolver:peek (qname, qtype, qclass)    -- - - - - - - - - - - -  peek
+function resolver:peek (qname, qtype, qclass, n)    -- - - - - - - - - - - -  peek
        qname, qtype, qclass = standardize(qname, qtype, qclass);
        local rrs = get(self.cache, qclass, qtype, qname);
-       if not rrs then return nil; end
+       if not rrs then
+               if n then if n <= 0 then return end else n = 3 end
+               rrs = get(self.cache, qclass, "CNAME", qname);
+               if not (rrs and rrs[1]) then return end
+               return self:peek(rrs[1].cname, qtype, qclass, n - 1);
+       end
        if prune(rrs, socket.gettime()) and qtype == '*' or not next(rrs) then
                set(self.cache, qclass, qtype, qname, nil);
                return nil;
        end
-       if self.unsorted[rrs] then table.sort (rrs, comp_mx); end
+       if self.unsorted[rrs] then table.sort (rrs, comp_mx); self.unsorted[rrs] = nil; end
        return rrs;
 end
 
@@ -751,16 +754,16 @@ function resolver:query(qname, qtype, qclass)    -- - - - - - - - - - -- query
        self.active[id] = self.active[id] or {};
        self.active[id][question] = o;
 
-       -- remember which coroutine wants the answer
-       if co then
-               set(self.wanted, qclass, qtype, qname, co, true);
-       end
-
        local conn, err = self:getsocket(o.server)
        if not conn then
                return nil, err;
        end
        conn:send (o.packet)
+
+       -- remember which coroutine wants the answer
+       if co then
+               set(self.wanted, qclass, qtype, qname, co, true);
+       end
        
        if timer and self.timeout then
                local num_servers = #self.server;
@@ -838,7 +841,7 @@ function resolver:receive(rset)    -- - - - - - - - - - - - - - - - -  receive
        rset = rset or self.socket;
 
        local response;
-       for i,sock in pairs(rset) do
+       for _, sock in pairs(rset) do
 
                if self.socketset[sock] then
                        local packet = sock:receive();
@@ -849,7 +852,7 @@ function resolver:receive(rset)    -- - - - - - - - - - - - - - - - -  receive
                                        --print('received response');
                                        --self.print(response);
 
-                                       for j,rr in pairs(response.answer) do
+                                       for _, rr in pairs(response.answer) do
                                                if rr.name:sub(-#response.question[1].name, -1) == response.question[1].name then
                                                        self:remember(rr, response.question[1].type)
                                                end
@@ -891,7 +894,7 @@ function resolver:feed(sock, packet, force)
                --print('received response');
                --self.print(response);
 
-               for j,rr in pairs(response.answer) do
+               for _, rr in pairs(response.answer) do
                        self:remember(rr, response.question[1].type);
                end
 
@@ -1042,8 +1045,6 @@ end
 
 
 function dns.resolver ()    -- - - - - - - - - - - - - - - - - - - - - resolver
-       -- this function seems to be redundant with resolver.new ()
-
        local r = { active = {}, cache = {}, unsorted = {}, wanted = {}, best_server = 1 };
        setmetatable (r, resolver);
        setmetatable (r.cache, cache_metatable);