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-rw-r--r--net/dns.lua1574
1 files changed, 895 insertions, 679 deletions
diff --git a/net/dns.lua b/net/dns.lua
index 48c08218..c9c51fe8 100644
--- a/net/dns.lua
+++ b/net/dns.lua
@@ -2,8 +2,6 @@
-- 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
@@ -14,21 +12,65 @@
-- reference: http://tools.ietf.org/html/rfc1876 (LOC)
-require 'socket'
-local ztact = require 'util.ztact'
-local require = require
-
-local coroutine, io, math, socket, string, table =
- coroutine, io, math, socket, string, table
-
-local ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack =
- ipairs, next, pairs, print, setmetatable, tostring, assert, error, unpack
-
-local get, set = ztact.get, ztact.set
-
+local socket = require "socket";
+local timer = require "util.timer";
+
+local _, windows = pcall(require, "util.windows");
+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 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;
-------------------------------------------------- module dns
-module ('dns')
+module('dns')
local dns = _M;
@@ -38,826 +80,1000 @@ local dns = _M;
local append = table.insert
-local function highbyte (i) -- - - - - - - - - - - - - - - - - - - highbyte
- return (i-(i%0x100))/0x100
- end
+local function highbyte(i) -- - - - - - - - - - - - - - - - - - - highbyte
+ return (i-(i%0x100))/0x100;
+end
local function augment (t) -- - - - - - - - - - - - - - - - - - - - augment
- local a = {}
- for i,s in pairs (t) do a[i] = s a[s] = s a[string.lower (s)] = s end
- return a
- end
+ local a = {};
+ for i,s in pairs(t) do
+ a[i] = s;
+ a[s] = s;
+ a[string.lower(s)] = s;
+ end
+ return a;
+end
local function encode (t) -- - - - - - - - - - - - - - - - - - - - - encode
- local code = {}
- for i,s in pairs (t) do
- local word = string.char (highbyte (i), i %0x100)
- code[i] = word
- code[s] = word
- code[string.lower (s)] = word
- end
- return code
- end
+ local code = {};
+ for i,s in pairs(t) do
+ local word = string.char(highbyte(i), i%0x100);
+ code[i] = word;
+ code[s] = word;
+ code[string.lower(s)] = word;
+ end
+ return code;
+end
dns.types = {
- 'A', 'NS', 'MD', 'MF', 'CNAME', 'SOA', 'MB', 'MG', 'MR', 'NULL', 'WKS',
- 'PTR', 'HINFO', 'MINFO', 'MX', 'TXT',
- [ 28] = 'AAAA', [ 29] = 'LOC', [ 33] = 'SRV',
- [252] = 'AXFR', [253] = 'MAILB', [254] = 'MAILA', [255] = '*' }
+ 'A', 'NS', 'MD', 'MF', 'CNAME', 'SOA', 'MB', 'MG', 'MR', 'NULL', 'WKS',
+ 'PTR', 'HINFO', 'MINFO', 'MX', 'TXT',
+ [ 28] = 'AAAA', [ 29] = 'LOC', [ 33] = 'SRV',
+ [252] = 'AXFR', [253] = 'MAILB', [254] = 'MAILA', [255] = '*' };
-dns.classes = { 'IN', 'CS', 'CH', 'HS', [255] = '*' }
+dns.classes = { 'IN', 'CS', 'CH', 'HS', [255] = '*' };
-dns.type = augment (dns.types)
-dns.class = augment (dns.classes)
-dns.typecode = encode (dns.types)
-dns.classcode = encode (dns.classes)
+dns.type = augment (dns.types);
+dns.class = augment (dns.classes);
+dns.typecode = encode (dns.types);
+dns.classcode = encode (dns.classes);
-local function standardize (qname, qtype, qclass) -- - - - - - - standardize
- if string.byte (qname, -1) ~= 0x2E then qname = qname..'.' end
- qname = string.lower (qname)
- return qname, dns.type[qtype or 'A'], dns.class[qclass or 'IN']
- end
-
-
-local function prune (rrs, time, soft) -- - - - - - - - - - - - - - - prune
-
- time = time or socket.gettime ()
- for i,rr in pairs (rrs) do
+local function standardize(qname, qtype, qclass) -- - - - - - - standardize
+ if string.byte(qname, -1) ~= 0x2E then qname = qname..'.'; end
+ qname = string.lower(qname);
+ return qname, dns.type[qtype or 'A'], dns.class[qclass or 'IN'];
+end
- if rr.tod then
- -- rr.tod = rr.tod - 50 -- accelerated decripitude
- rr.ttl = math.floor (rr.tod - time)
- if rr.ttl <= 0 then rrs[i] = nil end
- elseif soft == 'soft' then -- What is this? I forget!
- assert (rr.ttl == 0)
- rrs[i] = nil
- end end end
+local function prune(rrs, time, soft) -- - - - - - - - - - - - - - - prune
+ time = time or socket.gettime();
+ for i,rr in pairs(rrs) do
+ if rr.tod then
+ -- rr.tod = rr.tod - 50 -- accelerated decripitude
+ rr.ttl = math.floor(rr.tod - time);
+ if rr.ttl <= 0 then
+ table.remove(rrs, i);
+ return prune(rrs, time, soft); -- Re-iterate
+ end
+ elseif soft == 'soft' then -- What is this? I forget!
+ assert(rr.ttl == 0);
+ rrs[i] = nil;
+ end
+ end
+end
-- metatables & co. ------------------------------------------ metatables & co.
-local resolver = {}
-resolver.__index = resolver
-
+local resolver = {};
+resolver.__index = resolver;
-local SRV_tostring
+resolver.timeout = default_timeout;
+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 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
- end
+local special_tostrings = {
+ LOC = resolver.LOC_tostring;
+ MX = function (rr)
+ return string.format('%2i %s', rr.pref, rr.mx);
+ end;
+ SRV = function (rr)
+ local s = rr.srv;
+ return string.format('%5d %5d %5d %s', s.priority, s.weight, s.port, s.target);
+ end;
+};
+
+local rr_metatable = {}; -- - - - - - - - - - - - - - - - - - - rr_metatable
+function rr_metatable.__tostring(rr)
+ 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
-local rrs_metatable = {} -- - - - - - - - - - - - - - - - - - rrs_metatable
-function rrs_metatable.__tostring (rrs)
- local t = {}
- for i,rr in pairs (rrs) do append (t, tostring (rr)..'\n') end
- return table.concat (t)
- end
+local rrs_metatable = {}; -- - - - - - - - - - - - - - - - - - rrs_metatable
+function rrs_metatable.__tostring(rrs)
+ local t = {};
+ for i,rr in pairs(rrs) do
+ append(t, tostring(rr)..'\n');
+ end
+ return table.concat(t);
+end
-local cache_metatable = {} -- - - - - - - - - - - - - - - - cache_metatable
-function cache_metatable.__tostring (cache)
- local time = socket.gettime ()
- local t = {}
- for class,types in pairs (cache) do
- for type,names in pairs (types) do
- for name,rrs in pairs (names) do
- prune (rrs, time)
- append (t, tostring (rrs)) end end end
- return table.concat (t)
- end
+local cache_metatable = {}; -- - - - - - - - - - - - - - - - cache_metatable
+function cache_metatable.__tostring(cache)
+ local time = socket.gettime();
+ local t = {};
+ for class,types in pairs(cache) do
+ for type,names in pairs(types) do
+ for name,rrs in pairs(names) do
+ prune(rrs, time);
+ append(t, tostring(rrs));
+ end
+ end
+ end
+ return table.concat(t);
+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
+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 (10000*socket.gettime ())
- dns.random = math.random
- return dns.random (...)
- end
-
-
-local function encodeHeader (o) -- - - - - - - - - - - - - - - encodeHeader
+function dns.random(...) -- - - - - - - - - - - - - - - - - - - dns.random
+ math.randomseed(math.floor(10000*socket.gettime()) % 0x100000000);
+ dns.random = math.random;
+ return dns.random(...);
+end
- o = o or {}
- o.id = o.id or -- 16b (random) id
- dns.random (0, 0xffff)
+local function encodeHeader(o) -- - - - - - - - - - - - - - - encodeHeader
+ o = o or {};
+ o.id = o.id or dns.random(0, 0xffff); -- 16b (random) id
- o.rd = o.rd or 1 -- 1b 1 recursion desired
- o.tc = o.tc or 0 -- 1b 1 truncated response
- o.aa = o.aa or 0 -- 1b 1 authoritative response
- o.opcode = o.opcode or 0 -- 4b 0 query
- -- 1 inverse query
+ o.rd = o.rd or 1; -- 1b 1 recursion desired
+ o.tc = o.tc or 0; -- 1b 1 truncated response
+ o.aa = o.aa or 0; -- 1b 1 authoritative response
+ o.opcode = o.opcode or 0; -- 4b 0 query
+ -- 1 inverse query
-- 2 server status request
-- 3-15 reserved
- o.qr = o.qr or 0 -- 1b 0 query, 1 response
+ o.qr = o.qr or 0; -- 1b 0 query, 1 response
- o.rcode = o.rcode or 0 -- 4b 0 no error
+ o.rcode = o.rcode or 0; -- 4b 0 no error
-- 1 format error
-- 2 server failure
-- 3 name error
-- 4 not implemented
-- 5 refused
-- 6-15 reserved
- o.z = o.z or 0 -- 3b 0 resvered
- o.ra = o.ra or 0 -- 1b 1 recursion available
-
- o.qdcount = o.qdcount or 1 -- 16b number of question RRs
- o.ancount = o.ancount or 0 -- 16b number of answers RRs
- o.nscount = o.nscount or 0 -- 16b number of nameservers RRs
- o.arcount = o.arcount or 0 -- 16b number of additional RRs
-
- -- string.char() rounds, so prevent roundup with -0.4999
- local header = string.char (
- highbyte (o.id), o.id %0x100,
- o.rd + 2*o.tc + 4*o.aa + 8*o.opcode + 128*o.qr,
- o.rcode + 16*o.z + 128*o.ra,
- highbyte (o.qdcount), o.qdcount %0x100,
- highbyte (o.ancount), o.ancount %0x100,
- highbyte (o.nscount), o.nscount %0x100,
- highbyte (o.arcount), o.arcount %0x100 )
-
- return header, o.id
- end
-
-
-local function encodeName (name) -- - - - - - - - - - - - - - - - encodeName
- local t = {}
- for part in string.gmatch (name, '[^.]+') do
- append (t, string.char (string.len (part)))
- append (t, part)
- end
- append (t, string.char (0))
- return table.concat (t)
- end
-
-
-local function encodeQuestion (qname, qtype, qclass) -- - - - encodeQuestion
- qname = encodeName (qname)
- qtype = dns.typecode[qtype or 'a']
- qclass = dns.classcode[qclass or 'in']
- return qname..qtype..qclass;
- end
-
-
-function resolver:byte (len) -- - - - - - - - - - - - - - - - - - - - - byte
- len = len or 1
- local offset = self.offset
- local last = offset + len - 1
- if last > #self.packet then
- error (string.format ('out of bounds: %i>%i', last, #self.packet)) end
- self.offset = offset + len
- return string.byte (self.packet, offset, last)
- end
-
-
-function resolver:word () -- - - - - - - - - - - - - - - - - - - - - - word
- local b1, b2 = self:byte (2)
- return 0x100*b1 + b2
- end
+ o.z = o.z or 0; -- 3b 0 resvered
+ o.ra = o.ra or 0; -- 1b 1 recursion available
+
+ o.qdcount = o.qdcount or 1; -- 16b number of question RRs
+ o.ancount = o.ancount or 0; -- 16b number of answers RRs
+ o.nscount = o.nscount or 0; -- 16b number of nameservers RRs
+ o.arcount = o.arcount or 0; -- 16b number of additional RRs
+
+ -- string.char() rounds, so prevent roundup with -0.4999
+ local header = string.char(
+ highbyte(o.id), o.id %0x100,
+ o.rd + 2*o.tc + 4*o.aa + 8*o.opcode + 128*o.qr,
+ o.rcode + 16*o.z + 128*o.ra,
+ highbyte(o.qdcount), o.qdcount %0x100,
+ highbyte(o.ancount), o.ancount %0x100,
+ highbyte(o.nscount), o.nscount %0x100,
+ highbyte(o.arcount), o.arcount %0x100
+ );
+
+ return header, o.id;
+end
+
+
+local function encodeName(name) -- - - - - - - - - - - - - - - - encodeName
+ local t = {};
+ for part in string.gmatch(name, '[^.]+') do
+ append(t, string.char(string.len(part)));
+ append(t, part);
+ end
+ append(t, string.char(0));
+ return table.concat(t);
+end
+
+
+local function encodeQuestion(qname, qtype, qclass) -- - - - encodeQuestion
+ qname = encodeName(qname);
+ qtype = dns.typecode[qtype or 'a'];
+ qclass = dns.classcode[qclass or 'in'];
+ return qname..qtype..qclass;
+end
+
+
+function resolver:byte(len) -- - - - - - - - - - - - - - - - - - - - - byte
+ len = len or 1;
+ local offset = self.offset;
+ local last = offset + len - 1;
+ if last > #self.packet then
+ error(string.format('out of bounds: %i>%i', last, #self.packet));
+ end
+ self.offset = offset + len;
+ return string.byte(self.packet, offset, last);
+end
+
+
+function resolver:word() -- - - - - - - - - - - - - - - - - - - - - - word
+ local b1, b2 = self:byte(2);
+ return 0x100*b1 + b2;
+end
function resolver:dword () -- - - - - - - - - - - - - - - - - - - - - dword
- local b1, b2, b3, b4 = self:byte (4)
- --print ('dword', b1, b2, b3, b4)
- return 0x1000000*b1 + 0x10000*b2 + 0x100*b3 + b4
- end
+ local b1, b2, b3, b4 = self:byte(4);
+ --print('dword', b1, b2, b3, b4);
+ return 0x1000000*b1 + 0x10000*b2 + 0x100*b3 + b4;
+end
-function resolver:sub (len) -- - - - - - - - - - - - - - - - - - - - - - sub
- len = len or 1
- local s = string.sub (self.packet, self.offset, self.offset + len - 1)
- self.offset = self.offset + len
- return s
- end
+function resolver:sub(len) -- - - - - - - - - - - - - - - - - - - - - - sub
+ len = len or 1;
+ local s = string.sub(self.packet, self.offset, self.offset + len - 1);
+ self.offset = self.offset + len;
+ return s;
+end
-function resolver:header (force) -- - - - - - - - - - - - - - - - - - header
-
- local id = self:word ()
- --print (string.format (':header id %x', id))
- if not self.active[id] and not force then return nil end
-
- local h = { id = id }
-
- local b1, b2 = self:byte (2)
-
- h.rd = b1 %2
- h.tc = b1 /2%2
- h.aa = b1 /4%2
- h.opcode = b1 /8%16
- h.qr = b1 /128
+function resolver:header(force) -- - - - - - - - - - - - - - - - - - header
+ local id = self:word();
+ --print(string.format(':header id %x', id));
+ if not self.active[id] and not force then return nil; end
- h.rcode = b2 %16
- h.z = b2 /16%8
- h.ra = b2 /128
-
- h.qdcount = self:word ()
- h.ancount = self:word ()
- h.nscount = self:word ()
- h.arcount = self:word ()
-
- for k,v in pairs (h) do h[k] = v-v%1 end
-
- return h
- end
-
-
-function resolver:name () -- - - - - - - - - - - - - - - - - - - - - - name
- local remember, pointers = nil, 0
- local len = self:byte ()
- local n = {}
- while len > 0 do
- if len >= 0xc0 then -- name is "compressed"
- pointers = pointers + 1
- if pointers >= 20 then error ('dns error: 20 pointers') end
- local offset = ((len-0xc0)*0x100) + self:byte ()
- remember = remember or self.offset
- self.offset = offset + 1 -- +1 for lua
- else -- name is not compressed
- append (n, self:sub (len)..'.')
- end
- len = self:byte ()
- end
- self.offset = remember or self.offset
- return table.concat (n)
- end
+ local h = { id = id };
+ local b1, b2 = self:byte(2);
-function resolver:question () -- - - - - - - - - - - - - - - - - - question
- local q = {}
- q.name = self:name ()
- q.type = dns.type[self:word ()]
- q.class = dns.class[self:word ()]
- return q
- end
+ h.rd = b1 %2;
+ h.tc = b1 /2%2;
+ h.aa = b1 /4%2;
+ h.opcode = b1 /8%16;
+ h.qr = b1 /128;
+ h.rcode = b2 %16;
+ h.z = b2 /16%8;
+ h.ra = b2 /128;
-function resolver:A (rr) -- - - - - - - - - - - - - - - - - - - - - - - - A
- local b1, b2, b3, b4 = self:byte (4)
- rr.a = string.format ('%i.%i.%i.%i', b1, b2, b3, b4)
- end
+ h.qdcount = self:word();
+ h.ancount = self:word();
+ h.nscount = self:word();
+ h.arcount = self:word();
+ for k,v in pairs(h) do h[k] = v-v%1; end
-function resolver:CNAME (rr) -- - - - - - - - - - - - - - - - - - - - CNAME
- rr.cname = self:name ()
- end
+ return h;
+end
-function resolver:MX (rr) -- - - - - - - - - - - - - - - - - - - - - - - MX
- rr.pref = self:word ()
- rr.mx = self:name ()
- end
+function resolver:name() -- - - - - - - - - - - - - - - - - - - - - - name
+ local remember, pointers = nil, 0;
+ local len = self:byte();
+ local n = {};
+ if len == 0 then return "." end -- Root label
+ while len > 0 do
+ if len >= 0xc0 then -- name is "compressed"
+ pointers = pointers + 1;
+ if pointers >= 20 then error('dns error: 20 pointers'); end;
+ local offset = ((len-0xc0)*0x100) + self:byte();
+ remember = remember or self.offset;
+ self.offset = offset + 1; -- +1 for lua
+ else -- name is not compressed
+ append(n, self:sub(len)..'.');
+ end
+ len = self:byte();
+ end
+ self.offset = remember or self.offset;
+ return table.concat(n);
+end
-function resolver:LOC_nibble_power () -- - - - - - - - - - LOC_nibble_power
- local b = self:byte ()
- --print ('nibbles', ((b-(b%0x10))/0x10), (b%0x10))
- return ((b-(b%0x10))/0x10) * (10^(b%0x10))
- end
+function resolver:question() -- - - - - - - - - - - - - - - - - - question
+ local q = {};
+ q.name = self:name();
+ q.type = dns.type[self:word()];
+ q.class = dns.class[self:word()];
+ return q;
+end
-function resolver:LOC (rr) -- - - - - - - - - - - - - - - - - - - - - - LOC
- rr.version = self:byte ()
- if rr.version == 0 then
- rr.loc = rr.loc or {}
- rr.loc.size = self:LOC_nibble_power ()
- rr.loc.horiz_pre = self:LOC_nibble_power ()
- rr.loc.vert_pre = self:LOC_nibble_power ()
- rr.loc.latitude = self:dword ()
- rr.loc.longitude = self:dword ()
- rr.loc.altitude = self:dword ()
- end end
+function resolver:A(rr) -- - - - - - - - - - - - - - - - - - - - - - - - A
+ local b1, b2, b3, b4 = self:byte(4);
+ rr.a = string.format('%i.%i.%i.%i', b1, b2, b3, b4);
+end
+function resolver:AAAA(rr)
+ local addr = {};
+ for i = 1, rr.rdlength, 2 do
+ local b1, b2 = self:byte(2);
+ table.insert(addr, ("%02x%02x"):format(b1, b2));
+ end
+ addr = table.concat(addr, ":"):gsub("%f[%x]0+(%x)","%1");
+ local zeros = {};
+ for item in addr:gmatch(":[0:]+:") do
+ table.insert(zeros, item)
+ end
+ if #zeros == 0 then
+ rr.aaaa = addr;
+ return
+ elseif #zeros > 1 then
+ table.sort(zeros, function(a, b) return #a > #b end);
+ end
+ rr.aaaa = addr:gsub(zeros[1], "::", 1):gsub("^0::", "::"):gsub("::0$", "::");
+end
-local function LOC_tostring_degrees (f, pos, neg) -- - - - - - - - - - - - -
- f = f - 0x80000000
- if f < 0 then pos = neg f = -f end
- local deg, min, msec
- msec = f%60000
- f = (f-msec)/60000
- min = f%60
- deg = (f-min)/60
- return string.format ('%3d %2d %2.3f %s', deg, min, msec/1000, pos)
- end
-
-
-function resolver.LOC_tostring (rr) -- - - - - - - - - - - - - LOC_tostring
-
- local t = {}
-
- --[[
- for k,name in pairs { 'size', 'horiz_pre', 'vert_pre',
- 'latitude', 'longitude', 'altitude' } do
- append (t, string.format ('%4s%-10s: %12.0f\n', '', name, rr.loc[name]))
- end
- --]]
-
- append ( t, string.format (
- '%s %s %.2fm %.2fm %.2fm %.2fm',
- LOC_tostring_degrees (rr.loc.latitude, 'N', 'S'),
- LOC_tostring_degrees (rr.loc.longitude, 'E', 'W'),
- (rr.loc.altitude - 10000000) / 100,
- rr.loc.size / 100,
- rr.loc.horiz_pre / 100,
- rr.loc.vert_pre / 100 ) )
-
- return table.concat (t)
- end
-
-
-function resolver:NS (rr) -- - - - - - - - - - - - - - - - - - - - - - - NS
- rr.ns = self:name ()
- end
-
+function resolver:CNAME(rr) -- - - - - - - - - - - - - - - - - - - - CNAME
+ rr.cname = self:name();
+end
-function resolver:SOA (rr) -- - - - - - - - - - - - - - - - - - - - - - SOA
- end
+function resolver:MX(rr) -- - - - - - - - - - - - - - - - - - - - - - - MX
+ rr.pref = self:word();
+ rr.mx = self:name();
+end
-function resolver:SRV (rr) -- - - - - - - - - - - - - - - - - - - - - - SRV
- rr.srv = {}
- rr.srv.priority = self:word ()
- rr.srv.weight = self:word ()
- rr.srv.port = self:word ()
- rr.srv.target = self:name ()
- end
+function resolver:LOC_nibble_power() -- - - - - - - - - - LOC_nibble_power
+ local b = self:byte();
+ --print('nibbles', ((b-(b%0x10))/0x10), (b%0x10));
+ return ((b-(b%0x10))/0x10) * (10^(b%0x10));
+end
-function SRV_tostring (rr) -- - - - - - - - - - - - - - - - - - SRV_tostring
- local s = rr.srv
- return string.format ( '%5d %5d %5d %s',
- s.priority, s.weight, s.port, s.target )
- end
+function resolver:LOC(rr) -- - - - - - - - - - - - - - - - - - - - - - LOC
+ rr.version = self:byte();
+ if rr.version == 0 then
+ rr.loc = rr.loc or {};
+ rr.loc.size = self:LOC_nibble_power();
+ rr.loc.horiz_pre = self:LOC_nibble_power();
+ rr.loc.vert_pre = self:LOC_nibble_power();
+ rr.loc.latitude = self:dword();
+ rr.loc.longitude = self:dword();
+ rr.loc.altitude = self:dword();
+ end
+end
-function resolver:TXT (rr) -- - - - - - - - - - - - - - - - - - - - - - TXT
- rr.txt = self:sub (rr.rdlength)
- end
+local function LOC_tostring_degrees(f, pos, neg) -- - - - - - - - - - - - -
+ f = f - 0x80000000;
+ if f < 0 then pos = neg; f = -f; end
+ local deg, min, msec;
+ msec = f%60000;
+ f = (f-msec)/60000;
+ min = f%60;
+ deg = (f-min)/60;
+ return string.format('%3d %2d %2.3f %s', deg, min, msec/1000, pos);
+end
-function resolver:rr () -- - - - - - - - - - - - - - - - - - - - - - - - rr
- local rr = {}
- setmetatable (rr, rr_metatable)
- rr.name = self:name (self)
- rr.type = dns.type[self:word ()] or rr.type
- rr.class = dns.class[self:word ()] or rr.class
- rr.ttl = 0x10000*self:word () + self:word ()
- rr.rdlength = self:word ()
- if rr.ttl == 0 then -- pass
- else rr.tod = self.time + rr.ttl end
+function resolver.LOC_tostring(rr) -- - - - - - - - - - - - - LOC_tostring
+ local t = {};
- local remember = self.offset
- local rr_parser = self[dns.type[rr.type]]
- if rr_parser then rr_parser (self, rr) end
- self.offset = remember
- rr.rdata = self:sub (rr.rdlength)
- return rr
- end
+ --[[
+ for k,name in pairs { 'size', 'horiz_pre', 'vert_pre', 'latitude', 'longitude', 'altitude' } do
+ append(t, string.format('%4s%-10s: %12.0f\n', '', name, rr.loc[name]));
+ end
+ --]]
+
+ append(t, string.format(
+ '%s %s %.2fm %.2fm %.2fm %.2fm',
+ LOC_tostring_degrees (rr.loc.latitude, 'N', 'S'),
+ LOC_tostring_degrees (rr.loc.longitude, 'E', 'W'),
+ (rr.loc.altitude - 10000000) / 100,
+ rr.loc.size / 100,
+ rr.loc.horiz_pre / 100,
+ rr.loc.vert_pre / 100
+ ));
+
+ return table.concat(t);
+end
-function resolver:rrs (count) -- - - - - - - - - - - - - - - - - - - - - rrs
- local rrs = {}
- for i = 1,count do append (rrs, self:rr ()) end
- return rrs
- end
+function resolver:NS(rr) -- - - - - - - - - - - - - - - - - - - - - - - NS
+ rr.ns = self:name();
+end
-function resolver:decode (packet, force) -- - - - - - - - - - - - - - decode
+function resolver:SOA(rr) -- - - - - - - - - - - - - - - - - - - - - - SOA
+end
- self.packet, self.offset = packet, 1
- local header = self:header (force)
- if not header then return nil end
- local response = { header = header }
- response.question = {}
- local offset = self.offset
- for i = 1,response.header.qdcount do
- append (response.question, self:question ()) end
- response.question.raw = string.sub (self.packet, offset, self.offset - 1)
+function resolver:SRV(rr) -- - - - - - - - - - - - - - - - - - - - - - SRV
+ rr.srv = {};
+ rr.srv.priority = self:word();
+ rr.srv.weight = self:word();
+ rr.srv.port = self:word();
+ rr.srv.target = self:name();
+end
- if not force then
- if not self.active[response.header.id] or
- not self.active[response.header.id][response.question.raw] then
- return nil end end
+function resolver:PTR(rr)
+ rr.ptr = self:name();
+end
- response.answer = self:rrs (response.header.ancount)
- response.authority = self:rrs (response.header.nscount)
- response.additional = self:rrs (response.header.arcount)
+function resolver:TXT(rr) -- - - - - - - - - - - - - - - - - - - - - - TXT
+ rr.txt = self:sub (self:byte());
+end
- return response
- end
+function resolver:rr() -- - - - - - - - - - - - - - - - - - - - - - - - rr
+ local rr = {};
+ setmetatable(rr, rr_metatable);
+ rr.name = self:name(self);
+ rr.type = dns.type[self:word()] or rr.type;
+ rr.class = dns.class[self:word()] or rr.class;
+ rr.ttl = 0x10000*self:word() + self:word();
+ rr.rdlength = self:word();
--- socket layer -------------------------------------------------- socket layer
+ if rr.ttl <= 0 then
+ rr.tod = self.time + 30;
+ else
+ rr.tod = self.time + rr.ttl;
+ end
+
+ local remember = self.offset;
+ local rr_parser = self[dns.type[rr.type]];
+ if rr_parser then rr_parser(self, rr); end
+ self.offset = remember;
+ rr.rdata = self:sub(rr.rdlength);
+ return rr;
+end
+
+
+function resolver:rrs (count) -- - - - - - - - - - - - - - - - - - - - - rrs
+ local rrs = {};
+ for i = 1,count do append(rrs, self:rr()); end
+ return rrs;
+end
+
+
+function resolver:decode(packet, force) -- - - - - - - - - - - - - - decode
+ self.packet, self.offset = packet, 1;
+ local header = self:header(force);
+ if not header then return nil; end
+ local response = { header = header };
+
+ response.question = {};
+ local offset = self.offset;
+ for i = 1,response.header.qdcount do
+ append(response.question, self:question());
+ end
+ response.question.raw = string.sub(self.packet, offset, self.offset - 1);
+
+ if not force then
+ if not self.active[response.header.id] or not self.active[response.header.id][response.question.raw] then
+ self.active[response.header.id] = nil;
+ return nil;
+ end
+ end
+
+ response.answer = self:rrs(response.header.ancount);
+ response.authority = self:rrs(response.header.nscount);
+ response.additional = self:rrs(response.header.arcount);
+
+ return response;
+end
-resolver.delays = { 1, 3, 11, 45 }
+-- socket layer -------------------------------------------------- socket layer
-function resolver:addnameserver (address) -- - - - - - - - - - addnameserver
- self.server = self.server or {}
- append (self.server, address)
- end
+resolver.delays = { 1, 3 };
-function resolver:setnameserver (address) -- - - - - - - - - - setnameserver
- self.server = {}
- self:addnameserver (address)
- end
+function resolver:addnameserver(address) -- - - - - - - - - - addnameserver
+ self.server = self.server or {};
+ append(self.server, address);
+end
-function resolver:adddefaultnameservers () -- - - - - adddefaultnameservers
- local resolv_conf = io.open("/etc/resolv.conf");
- if resolv_conf then
- for line in resolv_conf:lines() do
- local address = string.match (line, 'nameserver%s+(%d+%.%d+%.%d+%.%d+)')
- if address then self:addnameserver (address) end
- end
- else -- FIXME correct for windows, using opendns nameservers for now
- self:addnameserver ("208.67.222.222")
- self:addnameserver ("208.67.220.220")
- end
+function resolver:setnameserver(address) -- - - - - - - - - - setnameserver
+ self.server = {};
+ self:addnameserver(address);
end
-function resolver:getsocket (servernum) -- - - - - - - - - - - - - getsocket
+function resolver:adddefaultnameservers() -- - - - - adddefaultnameservers
+ if is_windows then
+ if windows and windows.get_nameservers then
+ for _, server in ipairs(windows.get_nameservers()) do
+ self:addnameserver(server);
+ end
+ end
+ if not self.server or #self.server == 0 then
+ -- TODO log warning about no nameservers, adding opendns servers as fallback
+ self:addnameserver("208.67.222.222");
+ self:addnameserver("208.67.220.220");
+ end
+ else -- posix
+ local resolv_conf = io.open("/etc/resolv.conf");
+ if resolv_conf then
+ for line in resolv_conf:lines() do
+ line = line:gsub("#.*$", "")
+ :match('^%s*nameserver%s+(.*)%s*$');
+ if line then
+ line:gsub("%f[%d.](%d+%.%d+%.%d+%.%d+)%f[^%d.]", function (address)
+ self:addnameserver(address)
+ end);
+ end
+ end
+ end
+ if not self.server or #self.server == 0 then
+ -- TODO log warning about no nameservers, adding localhost as the default nameserver
+ self:addnameserver("127.0.0.1");
+ end
+ end
+end
+
- self.socket = self.socket or {}
- self.socketset = self.socketset or {}
+function resolver:getsocket(servernum) -- - - - - - - - - - - - - getsocket
+ self.socket = self.socket or {};
+ self.socketset = self.socketset or {};
- local sock = self.socket[servernum]
- if sock then return sock end
+ local sock = self.socket[servernum];
+ if sock then return sock; end
- sock = socket.udp ()
- if self.socket_wrapper then sock = self.socket_wrapper (sock) end
- sock:settimeout (0)
- -- todo: attempt to use a random port, fallback to 0
- sock:setsockname ('*', 0)
- sock:setpeername (self.server[servernum], 53)
- self.socket[servernum] = sock
- self.socketset[sock] = sock
- return sock
- end
+ 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
+ sock:setsockname('*', 0);
+ sock:setpeername(self.server[servernum], 53);
+ self.socket[servernum] = sock;
+ self.socketset[sock] = servernum;
+ return sock;
+end
+function resolver:voidsocket(sock)
+ if self.socket[sock] then
+ self.socketset[self.socket[sock]] = nil;
+ self.socket[sock] = nil;
+ elseif self.socketset[sock] then
+ self.socket[self.socketset[sock]] = nil;
+ self.socketset[sock] = nil;
+ end
+ sock:close();
+end
-function resolver:socket_wrapper_set (func) -- - - - - - - socket_wrapper_set
- self.socket_wrapper = func
- end
+function resolver:socket_wrapper_set(func) -- - - - - - - socket_wrapper_set
+ self.socket_wrapper = func;
+end
function resolver:closeall () -- - - - - - - - - - - - - - - - - - closeall
- for i,sock in ipairs (self.socket) do self.socket[i]:close () end
- self.socket = {}
- end
-
+ for i,sock in ipairs(self.socket) do
+ self.socket[i] = nil;
+ self.socketset[sock] = nil;
+ sock:close();
+ end
+end
-function resolver:remember (rr, type) -- - - - - - - - - - - - - - remember
- --print ('remember', type, rr.class, rr.type, rr.name)
+function resolver:remember(rr, type) -- - - - - - - - - - - - - - remember
+ --print ('remember', type, rr.class, rr.type, rr.name)
+ local qname, qtype, qclass = standardize(rr.name, rr.type, rr.class);
- if type ~= '*' then
- type = rr.type
- local all = get (self.cache, rr.class, '*', rr.name)
- --print ('remember all', all)
- if all then append (all, rr) end
- end
+ if type ~= '*' then
+ type = qtype;
+ local all = get(self.cache, qclass, '*', qname);
+ --print('remember all', all);
+ if all then append(all, rr); end
+ end
- self.cache = self.cache or setmetatable ({}, cache_metatable)
- local rrs = get (self.cache, rr.class, type, rr.name) or
- set (self.cache, rr.class, type, rr.name, setmetatable ({}, rrs_metatable))
- append (rrs, rr)
+ self.cache = self.cache or setmetatable({}, cache_metatable);
+ local rrs = get(self.cache, qclass, type, qname) or
+ set(self.cache, qclass, type, qname, setmetatable({}, rrs_metatable));
+ append(rrs, rr);
- if type == 'MX' then self.unsorted[rrs] = true end
- end
+ if type == 'MX' then self.unsorted[rrs] = true; end
+end
-local function comp_mx (a, b) -- - - - - - - - - - - - - - - - - - - comp_mx
- return (a.pref == b.pref) and (a.mx < b.mx) or (a.pref < b.pref)
- end
+local function comp_mx(a, b) -- - - - - - - - - - - - - - - - - - - comp_mx
+ return (a.pref == b.pref) and (a.mx < b.mx) or (a.pref < b.pref);
+end
function resolver:peek (qname, qtype, qclass) -- - - - - - - - - - - - peek
- qname, qtype, qclass = standardize (qname, qtype, qclass)
- local rrs = get (self.cache, qclass, qtype, qname)
- if not rrs then return nil 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
- return rrs
- end
-
-
-function resolver:purge (soft) -- - - - - - - - - - - - - - - - - - - purge
- if soft == 'soft' then
- self.time = socket.gettime ()
- for class,types in pairs (self.cache or {}) do
- for type,names in pairs (types) do
- for name,rrs in pairs (names) do
- prune (rrs, self.time, 'soft')
- end end end
- else self.cache = {} end
- end
-
-
-function resolver:query (qname, qtype, qclass) -- - - - - - - - - - -- query
-
- qname, qtype, qclass = standardize (qname, qtype, qclass)
-
- if not self.server then self:adddefaultnameservers () end
-
- local question = encodeQuestion (qname, qtype, qclass)
- local peek = self:peek (qname, qtype, qclass)
- if peek then return peek end
-
- local header, id = encodeHeader ()
- --print ('query id', id, qclass, qtype, qname)
- local o = { packet = header..question,
- server = 1,
- delay = 1,
- retry = socket.gettime () + self.delays[1] }
- self:getsocket (o.server):send (o.packet)
-
- -- remember the query
- self.active[id] = self.active[id] or {}
- self.active[id][question] = o
-
- -- remember which coroutine wants the answer
- local co = coroutine.running ()
- if co then
- set (self.wanted, qclass, qtype, qname, co, true)
- --set (self.yielded, co, qclass, qtype, qname, true)
- end
-end
-
-
-
-function resolver:receive (rset) -- - - - - - - - - - - - - - - - - receive
-
- --print 'receive' print (self.socket)
- self.time = socket.gettime ()
- rset = rset or self.socket
-
- local response
- for i,sock in pairs (rset) do
-
- if self.socketset[sock] then
- local packet = sock:receive ()
- if packet then
-
- response = self:decode (packet)
- if response then
- --print 'received response'
- --self.print (response)
-
- for i,section in pairs { 'answer', 'authority', 'additional' } do
- for j,rr in pairs (response[section]) do
- self:remember (rr, response.question[1].type) end end
-
- -- retire the query
- local queries = self.active[response.header.id]
- if queries[response.question.raw] then
- queries[response.question.raw] = nil end
- if not next (queries) then self.active[response.header.id] = nil end
- if not next (self.active) then self:closeall () end
-
- -- was the query on the wanted list?
- local q = response.question
- local cos = get (self.wanted, q.class, q.type, q.name)
- if cos then
- for co in pairs (cos) do
- set (self.yielded, co, q.class, q.type, q.name, nil)
- if coroutine.status(co) == "suspended" then coroutine.resume (co) end
- end
- set (self.wanted, q.class, q.type, q.name, nil)
- end end end end end
-
- return response
- end
-
-
-function resolver:feed(sock, packet)
- --print 'receive' print (self.socket)
- self.time = socket.gettime ()
-
- local response = self:decode (packet)
- if response then
- --print 'received response'
- --self.print (response)
-
- for i,section in pairs { 'answer', 'authority', 'additional' } do
- for j,rr in pairs (response[section]) do
- self:remember (rr, response.question[1].type)
- end
- end
-
- -- retire the query
- local queries = self.active[response.header.id]
- if queries[response.question.raw] then
- queries[response.question.raw] = nil
- end
- if not next (queries) then self.active[response.header.id] = nil end
- if not next (self.active) then self:closeall () end
-
- -- was the query on the wanted list?
- local q = response.question[1]
- if q then
- local cos = get (self.wanted, q.class, q.type, q.name)
- if cos then
- for co in pairs (cos) do
- set (self.yielded, co, q.class, q.type, q.name, nil)
- if coroutine.status(co) == "suspended" then coroutine.resume (co) end
- end
- set (self.wanted, q.class, q.type, q.name, nil)
- end
- end
- end
-
- return response
-end
-
-function resolver:cancel(data)
- local cos = get (self.wanted, unpack(data, 1, 3))
- if cos then
- cos[data[4]] = nil;
+ qname, qtype, qclass = standardize(qname, qtype, qclass);
+ local rrs = get(self.cache, qclass, qtype, qname);
+ if not rrs then return nil; 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
+ return rrs;
+end
+
+
+function resolver:purge(soft) -- - - - - - - - - - - - - - - - - - - purge
+ if soft == 'soft' then
+ self.time = socket.gettime();
+ for class,types in pairs(self.cache or {}) do
+ for type,names in pairs(types) do
+ for name,rrs in pairs(names) do
+ prune(rrs, self.time, 'soft')
+ end
+ end
+ end
+ else self.cache = setmetatable({}, cache_metatable); end
end
-function resolver:pulse () -- - - - - - - - - - - - - - - - - - - - - pulse
- --print ':pulse'
- while self:receive() do end
- if not next (self.active) then return nil end
+function resolver:query(qname, qtype, qclass) -- - - - - - - - - - -- query
+ qname, qtype, qclass = standardize(qname, qtype, qclass)
+
+ if not self.server then self:adddefaultnameservers(); end
+
+ local question = encodeQuestion(qname, qtype, qclass);
+ local peek = self:peek (qname, qtype, qclass);
+ if peek then return peek; end
+
+ local header, id = encodeHeader();
+ --print ('query id', id, qclass, qtype, qname)
+ local o = {
+ packet = header..question,
+ server = self.best_server,
+ delay = 1,
+ retry = socket.gettime() + self.delays[1]
+ };
+
+ -- remember the query
+ self.active[id] = self.active[id] or {};
+ self.active[id][question] = o;
- self.time = socket.gettime ()
- for id,queries in pairs (self.active) do
- for question,o in pairs (queries) do
- if self.time >= o.retry then
+ -- remember which coroutine wants the answer
+ local co = coroutine.running();
+ if co then
+ set(self.wanted, qclass, qtype, qname, co, true);
+ --set(self.yielded, co, qclass, qtype, qname, true);
+ end
- o.server = o.server + 1
- if o.server > #self.server then
- o.server = 1
- o.delay = o.delay + 1
- end
+ 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
+ local num_servers = #self.server;
+ local i = 1;
+ timer.add_task(self.timeout, function ()
+ if get(self.wanted, qclass, qtype, qname, co) then
+ if i < num_servers then
+ i = i + 1;
+ self:servfail(conn);
+ o.server = self.best_server;
+ 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
- if o.delay > #self.delays then
- --print ('timeout')
- queries[question] = nil
- if not next (queries) then self.active[id] = nil end
- if not next (self.active) then return nil end
- else
- --print ('retry', o.server, o.delay)
- local _a = self.socket[o.server];
- if _a then _a:send (o.packet) end
- o.retry = self.time + self.delays[o.delay]
- end end end end
+function resolver:servfail(sock)
+ -- Resend all queries for this server
+
+ local num = self.socketset[sock]
+
+ -- Socket is dead now
+ self:voidsocket(sock);
+
+ -- Find all requests to the down server, and retry on the next server
+ self.time = socket.gettime();
+ for id,queries in pairs(self.active) do
+ for question,o in pairs(queries) do
+ if o.server == num then -- This request was to the broken server
+ o.server = o.server + 1 -- Use next server
+ if o.server > #self.server then
+ o.server = 1;
+ end
+
+ o.retries = (o.retries or 0) + 1;
+ if o.retries >= #self.server then
+ --print('timeout');
+ queries[question] = nil;
+ else
+ local _a = self:getsocket(o.server);
+ if _a then _a:send(o.packet); end
+ end
+ end
+ end
+ if next(queries) == nil then
+ self.active[id] = nil;
+ end
+ end
- if next (self.active) then return true end
- return nil
- end
+ if num == self.best_server then
+ self.best_server = self.best_server + 1;
+ if self.best_server > #self.server then
+ -- Exhausted all servers, try first again
+ self.best_server = 1;
+ end
+ end
+end
+function resolver:settimeout(seconds)
+ self.timeout = seconds;
+end
-function resolver:lookup (qname, qtype, qclass) -- - - - - - - - - - lookup
- self:query (qname, qtype, qclass)
- while self:pulse () do socket.select (self.socket, nil, 4) end
- --print (self.cache)
- return self:peek (qname, qtype, qclass)
- end
+function resolver:receive(rset) -- - - - - - - - - - - - - - - - - receive
+ --print('receive'); print(self.socket);
+ self.time = socket.gettime();
+ rset = rset or self.socket;
+
+ local response;
+ for i,sock in pairs(rset) do
+
+ if self.socketset[sock] then
+ local packet = sock:receive();
+ if packet then
+ response = self:decode(packet);
+ if response and self.active[response.header.id]
+ and self.active[response.header.id][response.question.raw] then
+ --print('received response');
+ --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
+ end
+
+ -- retire the query
+ local queries = self.active[response.header.id];
+ queries[response.question.raw] = nil;
+
+ if not next(queries) then self.active[response.header.id] = nil; end
+ if not next(self.active) then self:closeall(); end
+
+ -- was the query on the wanted list?
+ local q = response.question[1];
+ local cos = get(self.wanted, q.class, q.type, q.name);
+ if cos then
+ for co in pairs(cos) do
+ set(self.yielded, co, q.class, q.type, q.name, nil);
+ if coroutine.status(co) == "suspended" then coroutine.resume(co); end
+ end
+ set(self.wanted, q.class, q.type, q.name, nil);
+ end
+ end
+
+ end
+ end
+ end
-function resolver:lookupex (handler, qname, qtype, qclass) -- - - - - - - - - - lookup
- return self:peek (qname, qtype, qclass) or self:query (qname, qtype, qclass)
- end
+ return response;
+end
+function resolver:feed(sock, packet, force)
+ --print('receive'); print(self.socket);
+ self.time = socket.gettime();
+
+ local response = self:decode(packet, force);
+ if response and self.active[response.header.id]
+ and self.active[response.header.id][response.question.raw] then
+ --print('received response');
+ --self.print(response);
+
+ for j,rr in pairs(response.answer) do
+ self:remember(rr, response.question[1].type);
+ end
+
+ -- retire the query
+ local queries = self.active[response.header.id];
+ queries[response.question.raw] = nil;
+ if not next(queries) then self.active[response.header.id] = nil; end
+ if not next(self.active) then self:closeall(); end
+
+ -- was the query on the wanted list?
+ local q = response.question[1];
+ if q then
+ local cos = get(self.wanted, q.class, q.type, q.name);
+ if cos then
+ for co in pairs(cos) do
+ set(self.yielded, co, q.class, q.type, q.name, nil);
+ if coroutine.status(co) == "suspended" then coroutine.resume(co); end
+ end
+ set(self.wanted, q.class, q.type, q.name, nil);
+ end
+ end
+ end
+
+ return response;
+end
+
+function resolver:cancel(qclass, qtype, qname, co, call_handler)
+ local cos = get(self.wanted, qclass, qtype, qname);
+ if cos then
+ if call_handler then
+ coroutine.resume(co);
+ end
+ cos[co] = nil;
+ end
+end
+
+function resolver:pulse() -- - - - - - - - - - - - - - - - - - - - - pulse
+ --print(':pulse');
+ while self:receive() do end
+ if not next(self.active) then return nil; end
+
+ self.time = socket.gettime();
+ for id,queries in pairs(self.active) do
+ for question,o in pairs(queries) do
+ if self.time >= o.retry then
+
+ o.server = o.server + 1;
+ if o.server > #self.server then
+ o.server = 1;
+ o.delay = o.delay + 1;
+ end
+
+ if o.delay > #self.delays then
+ --print('timeout');
+ queries[question] = nil;
+ if not next(queries) then self.active[id] = nil; end
+ if not next(self.active) then return nil; end
+ else
+ --print('retry', o.server, o.delay);
+ local _a = self.socket[o.server];
+ if _a then _a:send(o.packet); end
+ o.retry = self.time + self.delays[o.delay];
+ end
+ end
+ end
+ end
+
+ if next(self.active) then return true; end
+ return nil;
+end
+
+
+function resolver:lookup(qname, qtype, qclass) -- - - - - - - - - - lookup
+ self:query (qname, qtype, qclass)
+ while self:pulse() do
+ local recvt = {}
+ for i, s in ipairs(self.socket) do
+ recvt[i] = s
+ end
+ socket.select(recvt, nil, 4)
+ end
+ --print(self.cache);
+ return self:peek(qname, qtype, qclass);
+end
+
+function resolver:lookupex(handler, qname, qtype, qclass) -- - - - - - - - - - lookup
+ 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
local hints = { -- - - - - - - - - - - - - - - - - - - - - - - - - - - hints
- qr = { [0]='query', 'response' },
- opcode = { [0]='query', 'inverse query', 'server status request' },
- aa = { [0]='non-authoritative', 'authoritative' },
- tc = { [0]='complete', 'truncated' },
- rd = { [0]='recursion not desired', 'recursion desired' },
- ra = { [0]='recursion not available', 'recursion available' },
- z = { [0]='(reserved)' },
- rcode = { [0]='no error', 'format error', 'server failure', 'name error',
- 'not implemented' },
-
- type = dns.type,
- class = dns.class, }
-
-
-local function hint (p, s) -- - - - - - - - - - - - - - - - - - - - - - hint
- return (hints[s] and hints[s][p[s]]) or '' end
-
-
-function resolver.print (response) -- - - - - - - - - - - - - resolver.print
-
- for s,s in pairs { 'id', 'qr', 'opcode', 'aa', 'tc', 'rd', 'ra', 'z',
- 'rcode', 'qdcount', 'ancount', 'nscount', 'arcount' } do
- print ( string.format ('%-30s', 'header.'..s),
- response.header[s], hint (response.header, s) )
- end
-
- for i,question in ipairs (response.question) do
- print (string.format ('question[%i].name ', i), question.name)
- print (string.format ('question[%i].type ', i), question.type)
- print (string.format ('question[%i].class ', i), question.class)
- end
-
- local common = { name=1, type=1, class=1, ttl=1, rdlength=1, rdata=1 }
- local tmp
- for s,s in pairs {'answer', 'authority', 'additional'} do
- for i,rr in pairs (response[s]) do
- for j,t in pairs { 'name', 'type', 'class', 'ttl', 'rdlength' } do
- tmp = string.format ('%s[%i].%s', s, i, t)
- print (string.format ('%-30s', tmp), rr[t], hint (rr, t))
- end
- for j,t in pairs (rr) do
- if not common[j] then
- tmp = string.format ('%s[%i].%s', s, i, j)
- print (string.format ('%-30s %s', tostring(tmp), tostring(t)))
- end end end end end
+ qr = { [0]='query', 'response' },
+ opcode = { [0]='query', 'inverse query', 'server status request' },
+ aa = { [0]='non-authoritative', 'authoritative' },
+ tc = { [0]='complete', 'truncated' },
+ rd = { [0]='recursion not desired', 'recursion desired' },
+ ra = { [0]='recursion not available', 'recursion available' },
+ z = { [0]='(reserved)' },
+ rcode = { [0]='no error', 'format error', 'server failure', 'name error', 'not implemented' },
+
+ type = dns.type,
+ class = dns.class
+};
+
+
+local function hint(p, s) -- - - - - - - - - - - - - - - - - - - - - - hint
+ return (hints[s] and hints[s][p[s]]) or '';
+end
--- module api ------------------------------------------------------ module api
+function resolver.print(response) -- - - - - - - - - - - - - resolver.print
+ for s,s in pairs { 'id', 'qr', 'opcode', 'aa', 'tc', 'rd', 'ra', 'z',
+ 'rcode', 'qdcount', 'ancount', 'nscount', 'arcount' } do
+ print( string.format('%-30s', 'header.'..s), response.header[s], hint(response.header, s) );
+ end
+ for i,question in ipairs(response.question) do
+ print(string.format ('question[%i].name ', i), question.name);
+ print(string.format ('question[%i].type ', i), question.type);
+ print(string.format ('question[%i].class ', i), question.class);
+ end
-local function resolve (func, ...) -- - - - - - - - - - - - - - resolver_get
- dns._resolver = dns._resolver or dns.resolver ()
- return func (dns._resolver, ...)
- end
+ local common = { name=1, type=1, class=1, ttl=1, rdlength=1, rdata=1 };
+ local tmp;
+ for s,s in pairs({'answer', 'authority', 'additional'}) do
+ for i,rr in pairs(response[s]) do
+ for j,t in pairs({ 'name', 'type', 'class', 'ttl', 'rdlength' }) do
+ tmp = string.format('%s[%i].%s', s, i, t);
+ print(string.format('%-30s', tmp), rr[t], hint(rr, t));
+ end
+ for j,t in pairs(rr) do
+ if not common[j] then
+ tmp = string.format('%s[%i].%s', s, i, j);
+ print(string.format('%-30s %s', tostring(tmp), tostring(t)));
+ end
+ end
+ end
+ end
+end
-function dns.resolver () -- - - - - - - - - - - - - - - - - - - - - resolver
+-- module api ------------------------------------------------------ module api
- -- this function seems to be redundant with resolver.new ()
- local r = { active = {}, cache = {}, unsorted = {}, wanted = {}, yielded = {} }
- setmetatable (r, resolver)
- setmetatable (r.cache, cache_metatable)
- setmetatable (r.unsorted, { __mode = 'kv' })
- return r
- end
+function dns.resolver () -- - - - - - - - - - - - - - - - - - - - - resolver
+ -- this function seems to be redundant with resolver.new ()
+ local r = { active = {}, cache = {}, unsorted = {}, wanted = {}, yielded = {}, best_server = 1 };
+ setmetatable (r, resolver);
+ setmetatable (r.cache, cache_metatable);
+ setmetatable (r.unsorted, { __mode = 'kv' });
+ return r;
+end
-function dns.lookup (...) -- - - - - - - - - - - - - - - - - - - - - lookup
- return resolve (resolver.lookup, ...) end
+local _resolver = dns.resolver();
+dns._resolver = _resolver;
+function dns.lookup(...) -- - - - - - - - - - - - - - - - - - - - - lookup
+ return _resolver:lookup(...);
+end
-function dns.purge (...) -- - - - - - - - - - - - - - - - - - - - - - purge
- return resolve (resolver.purge, ...) end
+function dns.tohostname(...)
+ return _resolver:tohostname(...);
+end
-function dns.peek (...) -- - - - - - - - - - - - - - - - - - - - - - - peek
- return resolve (resolver.peek, ...) end
+function dns.purge(...) -- - - - - - - - - - - - - - - - - - - - - - purge
+ return _resolver:purge(...);
+end
+function dns.peek(...) -- - - - - - - - - - - - - - - - - - - - - - - peek
+ return _resolver:peek(...);
+end
-function dns.query (...) -- - - - - - - - - - - - - - - - - - - - - - query
- return resolve (resolver.query, ...) end
+function dns.query(...) -- - - - - - - - - - - - - - - - - - - - - - query
+ return _resolver:query(...);
+end
-function dns.feed (...) -- - - - - - - - - - - - - - - - - - - - - - feed
- return resolve (resolver.feed, ...) end
+function dns.feed(...) -- - - - - - - - - - - - - - - - - - - - - - - feed
+ return _resolver:feed(...);
+end
-function dns.cancel(...) -- - - - - - - - - - - - - - - - - - - - - - cancel
- return resolve(resolver.cancel, ...) end
+function dns.cancel(...) -- - - - - - - - - - - - - - - - - - - - - - cancel
+ return _resolver:cancel(...);
+end
-function dns:socket_wrapper_set (...) -- - - - - - - - - socket_wrapper_set
- return resolve (resolver.socket_wrapper_set, ...) end
+function dns.settimeout(...)
+ return _resolver:settimeout(...);
+end
+function dns.socket_wrapper_set(...) -- - - - - - - - - socket_wrapper_set
+ return _resolver:socket_wrapper_set(...);
+end
-return dns
+return dns;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 09:52:01 +0000