net.server_select: Close all connections when quitting (and not just stepping), match...
[prosody.git] / net / dns.lua
index 2b03caf605af685408cd909d95592e7be6ee6d28..d893e38f5cc982cc4b3e9bf53a8a5e5f3dccdd42 100644 (file)
@@ -71,8 +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
@@ -213,20 +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
@@ -624,12 +615,12 @@ function resolver:getsocket(servernum)    -- - - - - - - - - - - - - getsocket
        local sock = self.socket[servernum];
        if sock then return sock; end
 
-       local err;
+       local ok, err;
        local peer = self.server[servernum];
        if peer:find(":") then
                sock, err = socket.udp6();
        else
-               sock, err = socket.udp();
+               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
@@ -637,10 +628,14 @@ function resolver:getsocket(servernum)    -- - - - - - - - - - - - - getsocket
        end
        sock:settimeout(0);
        -- todo: attempt to use a random port, fallback to 0
-       sock:setsockname('*', 0);
-       sock:setpeername(peer, 53);
        self.socket[servernum] = sock;
        self.socketset[sock] = servernum;
+       -- set{sock,peer}name can fail, eg because of local routing table
+       -- 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(peer, 53);
+       if not ok then return self:servfail(sock, err); end
        return sock;
 end
 
@@ -697,15 +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
 
@@ -788,13 +788,13 @@ function resolver:query(qname, qtype, qclass)    -- - - - - - - - - - -- query
        return true;
 end
 
-function resolver:servfail(sock)
+function resolver:servfail(sock, err)
        -- Resend all queries for this server
 
        local num = self.socketset[sock]
 
        -- Socket is dead now
-       self:voidsocket(sock);
+       sock = self:voidsocket(sock);
 
        -- Find all requests to the down server, and retry on the next server
        self.time = socket.gettime();
@@ -811,8 +811,8 @@ function resolver:servfail(sock)
                                        --print('timeout');
                                        queries[question] = nil;
                                else
-                                       local _a = self:getsocket(o.server);
-                                       if _a then _a:send(o.packet); end
+                                       sock, err = self:getsocket(o.server);
+                                       if sock then sock:send(o.packet); end
                                end
                        end
                end
@@ -828,6 +828,7 @@ function resolver:servfail(sock)
                        self.best_server = 1;
                end
        end
+       return sock, err;
 end
 
 function resolver:settimeout(seconds)
@@ -852,9 +853,7 @@ function resolver:receive(rset)    -- - - - - - - - - - - - - - - - -  receive
                                        --self.print(response);
 
                                        for j,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
+                                               self:remember(rr, response.question[1].type)
                                        end
 
                                        -- retire the query
@@ -1044,8 +1043,6 @@ 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);