author | Matthew Wild <mwild1@gmail.com> |
Thu, 04 Dec 2008 18:47:26 +0000 | |
changeset 545 | 60002993be04 |
parent 519 | cccd610a0ef9 |
child 615 | 4ae3e81513f3 |
permissions | -rw-r--r-- |
519
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parents:
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1 |
-- Prosody IM v0.1 |
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parents:
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|
2 |
-- Copyright (C) 2008 Matthew Wild |
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parents:
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3 |
-- Copyright (C) 2008 Waqas Hussain |
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parents:
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4 |
-- |
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parents:
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5 |
-- This program is free software; you can redistribute it and/or |
cccd610a0ef9
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parents:
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|
6 |
-- modify it under the terms of the GNU General Public License |
cccd610a0ef9
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parents:
453
diff
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|
7 |
-- as published by the Free Software Foundation; either version 2 |
cccd610a0ef9
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parents:
453
diff
changeset
|
8 |
-- of the License, or (at your option) any later version. |
cccd610a0ef9
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parents:
453
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9 |
-- |
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parents:
453
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|
10 |
-- This program is distributed in the hope that it will be useful, |
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parents:
453
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11 |
-- but WITHOUT ANY WARRANTY; without even the implied warranty of |
cccd610a0ef9
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parents:
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12 |
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
cccd610a0ef9
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parents:
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13 |
-- GNU General Public License for more details. |
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parents:
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14 |
-- |
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parents:
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15 |
-- You should have received a copy of the GNU General Public License |
cccd610a0ef9
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parents:
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16 |
-- along with this program; if not, write to the Free Software |
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parents:
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17 |
-- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
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parents:
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18 |
-- |
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parents:
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337 | 21 |
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23 |
-- public domain 20080404 lua@ztact.com |
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26 |
-- todo: quick (default) header generation |
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-- todo: nxdomain, error handling |
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-- todo: cache results of encodeName |
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-- reference: http://tools.ietf.org/html/rfc1035 |
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-- reference: http://tools.ietf.org/html/rfc1876 (LOC) |
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require 'socket' |
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local ztact = require 'util.ztact' |
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local coroutine, io, math, socket, string, table = |
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coroutine, io, math, socket, string, table |
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local ipairs, next, pairs, print, setmetatable, tostring, assert, error = |
c5617678cd7b
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parents:
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43 |
ipairs, next, pairs, print, setmetatable, tostring, assert, error |
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local get, set = ztact.get, ztact.set |
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-------------------------------------------------- module dns |
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module ('dns') |
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local dns = _M; |
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51 |
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52 |
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-- dns type & class codes ------------------------------ dns type & class codes |
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local append = table.insert |
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59 |
local function highbyte (i) -- - - - - - - - - - - - - - - - - - - highbyte |
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return (i-(i%0x100))/0x100 |
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end |
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63 |
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64 |
local function augment (t) -- - - - - - - - - - - - - - - - - - - - augment |
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local a = {} |
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for i,s in pairs (t) do a[i] = s a[s] = s a[string.lower (s)] = s end |
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return a |
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end |
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local function encode (t) -- - - - - - - - - - - - - - - - - - - - - encode |
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local code = {} |
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for i,s in pairs (t) do |
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local word = string.char (highbyte (i), i %0x100) |
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code[i] = word |
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code[s] = word |
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code[string.lower (s)] = word |
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78 |
end |
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return code |
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end |
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dns.types = { |
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'A', 'NS', 'MD', 'MF', 'CNAME', 'SOA', 'MB', 'MG', 'MR', 'NULL', 'WKS', |
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'PTR', 'HINFO', 'MINFO', 'MX', 'TXT', |
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[ 28] = 'AAAA', [ 29] = 'LOC', [ 33] = 'SRV', |
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[252] = 'AXFR', [253] = 'MAILB', [254] = 'MAILA', [255] = '*' } |
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dns.classes = { 'IN', 'CS', 'CH', 'HS', [255] = '*' } |
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dns.type = augment (dns.types) |
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dns.class = augment (dns.classes) |
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dns.typecode = encode (dns.types) |
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dns.classcode = encode (dns.classes) |
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local function standardize (qname, qtype, qclass) -- - - - - - - standardize |
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if string.byte (qname, -1) ~= 0x2E then qname = qname..'.' end |
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qname = string.lower (qname) |
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return qname, dns.type[qtype or 'A'], dns.class[qclass or 'IN'] |
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end |
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106 |
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local function prune (rrs, time, soft) -- - - - - - - - - - - - - - - prune |
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109 |
time = time or socket.gettime () |
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for i,rr in pairs (rrs) do |
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if rr.tod then |
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113 |
-- rr.tod = rr.tod - 50 -- accelerated decripitude |
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rr.ttl = math.floor (rr.tod - time) |
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if rr.ttl <= 0 then rrs[i] = nil end |
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elseif soft == 'soft' then -- What is this? I forget! |
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assert (rr.ttl == 0) |
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rrs[i] = nil |
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end end end |
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-- metatables & co. ------------------------------------------ metatables & co. |
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124 |
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125 |
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126 |
local resolver = {} |
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resolver.__index = resolver |
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local SRV_tostring |
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local rr_metatable = {} -- - - - - - - - - - - - - - - - - - - rr_metatable |
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function rr_metatable.__tostring (rr) |
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local s0 = string.format ( |
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'%2s %-5s %6i %-28s', rr.class, rr.type, rr.ttl, rr.name ) |
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local s1 = '' |
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if rr.type == 'A' then s1 = ' '..rr.a |
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elseif rr.type == 'MX' then |
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s1 = string.format (' %2i %s', rr.pref, rr.mx) |
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elseif rr.type == 'CNAME' then s1 = ' '..rr.cname |
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elseif rr.type == 'LOC' then s1 = ' '..resolver.LOC_tostring (rr) |
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elseif rr.type == 'NS' then s1 = ' '..rr.ns |
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elseif rr.type == 'SRV' then s1 = ' '..SRV_tostring (rr) |
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elseif rr.type == 'TXT' then s1 = ' '..rr.txt |
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else s1 = ' <UNKNOWN RDATA TYPE>' end |
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return s0..s1 |
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148 |
end |
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149 |
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150 |
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151 |
local rrs_metatable = {} -- - - - - - - - - - - - - - - - - - rrs_metatable |
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function rrs_metatable.__tostring (rrs) |
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c5617678cd7b
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parents:
378
diff
changeset
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153 |
local t = {} |
337 | 154 |
for i,rr in pairs (rrs) do append (t, tostring (rr)..'\n') end |
155 |
return table.concat (t) |
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end |
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local cache_metatable = {} -- - - - - - - - - - - - - - - - cache_metatable |
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function cache_metatable.__tostring (cache) |
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local time = socket.gettime () |
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local t = {} |
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for class,types in pairs (cache) do |
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for type,names in pairs (types) do |
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for name,rrs in pairs (names) do |
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prune (rrs, time) |
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append (t, tostring (rrs)) end end end |
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return table.concat (t) |
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end |
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function resolver:new () -- - - - - - - - - - - - - - - - - - - - - resolver |
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local r = { active = {}, cache = {}, unsorted = {} } |
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setmetatable (r, resolver) |
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setmetatable (r.cache, cache_metatable) |
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setmetatable (r.unsorted, { __mode = 'kv' }) |
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return r |
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end |
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-- packet layer -------------------------------------------------- packet layer |
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function dns.random (...) -- - - - - - - - - - - - - - - - - - - dns.random |
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math.randomseed (10000*socket.gettime ()) |
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dns.random = math.random |
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return dns.random (...) |
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end |
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local function encodeHeader (o) -- - - - - - - - - - - - - - - encodeHeader |
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o = o or {} |
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o.id = o.id or -- 16b (random) id |
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dns.random (0, 0xffff) |
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o.rd = o.rd or 1 -- 1b 1 recursion desired |
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o.tc = o.tc or 0 -- 1b 1 truncated response |
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o.aa = o.aa or 0 -- 1b 1 authoritative response |
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o.opcode = o.opcode or 0 -- 4b 0 query |
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-- 1 inverse query |
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-- 2 server status request |
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-- 3-15 reserved |
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o.qr = o.qr or 0 -- 1b 0 query, 1 response |
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o.rcode = o.rcode or 0 -- 4b 0 no error |
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-- 1 format error |
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-- 2 server failure |
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-- 3 name error |
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-- 4 not implemented |
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-- 5 refused |
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-- 6-15 reserved |
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o.z = o.z or 0 -- 3b 0 resvered |
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o.ra = o.ra or 0 -- 1b 1 recursion available |
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o.qdcount = o.qdcount or 1 -- 16b number of question RRs |
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o.ancount = o.ancount or 0 -- 16b number of answers RRs |
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o.nscount = o.nscount or 0 -- 16b number of nameservers RRs |
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o.arcount = o.arcount or 0 -- 16b number of additional RRs |
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-- string.char() rounds, so prevent roundup with -0.4999 |
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local header = string.char ( |
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highbyte (o.id), o.id %0x100, |
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o.rd + 2*o.tc + 4*o.aa + 8*o.opcode + 128*o.qr, |
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o.rcode + 16*o.z + 128*o.ra, |
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highbyte (o.qdcount), o.qdcount %0x100, |
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highbyte (o.ancount), o.ancount %0x100, |
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highbyte (o.nscount), o.nscount %0x100, |
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highbyte (o.arcount), o.arcount %0x100 ) |
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return header, o.id |
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end |
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local function encodeName (name) -- - - - - - - - - - - - - - - - encodeName |
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local t = {} |
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for part in string.gmatch (name, '[^.]+') do |
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append (t, string.char (string.len (part))) |
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append (t, part) |
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end |
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append (t, string.char (0)) |
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return table.concat (t) |
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end |
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local function encodeQuestion (qname, qtype, qclass) -- - - - encodeQuestion |
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qname = encodeName (qname) |
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qtype = dns.typecode[qtype or 'a'] |
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qclass = dns.classcode[qclass or 'in'] |
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return qname..qtype..qclass; |
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end |
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function resolver:byte (len) -- - - - - - - - - - - - - - - - - - - - - byte |
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len = len or 1 |
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local offset = self.offset |
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local last = offset + len - 1 |
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if last > #self.packet then |
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error (string.format ('out of bounds: %i>%i', last, #self.packet)) end |
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self.offset = offset + len |
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return string.byte (self.packet, offset, last) |
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end |
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function resolver:word () -- - - - - - - - - - - - - - - - - - - - - - word |
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local b1, b2 = self:byte (2) |
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return 0x100*b1 + b2 |
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end |
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function resolver:dword () -- - - - - - - - - - - - - - - - - - - - - dword |
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local b1, b2, b3, b4 = self:byte (4) |
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-- print ('dword', b1, b2, b3, b4) |
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return 0x1000000*b1 + 0x10000*b2 + 0x100*b3 + b4 |
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end |
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function resolver:sub (len) -- - - - - - - - - - - - - - - - - - - - - - sub |
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len = len or 1 |
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local s = string.sub (self.packet, self.offset, self.offset + len - 1) |
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self.offset = self.offset + len |
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return s |
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end |
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function resolver:header (force) -- - - - - - - - - - - - - - - - - - header |
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local id = self:word () |
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-- print (string.format (':header id %x', id)) |
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if not self.active[id] and not force then return nil end |
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local h = { id = id } |
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local b1, b2 = self:byte (2) |
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297 |
h.rd = b1 %2 |
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h.tc = b1 /2%2 |
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h.aa = b1 /4%2 |
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h.opcode = b1 /8%16 |
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h.qr = b1 /128 |
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h.rcode = b2 %16 |
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h.z = b2 /16%8 |
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h.ra = b2 /128 |
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307 |
h.qdcount = self:word () |
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h.ancount = self:word () |
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h.nscount = self:word () |
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h.arcount = self:word () |
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311 |
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for k,v in pairs (h) do h[k] = v-v%1 end |
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314 |
return h |
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end |
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316 |
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317 |
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318 |
function resolver:name () -- - - - - - - - - - - - - - - - - - - - - - name |
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319 |
local remember, pointers = nil, 0 |
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320 |
local len = self:byte () |
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321 |
local n = {} |
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322 |
while len > 0 do |
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323 |
if len >= 0xc0 then -- name is "compressed" |
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324 |
pointers = pointers + 1 |
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325 |
if pointers >= 20 then error ('dns error: 20 pointers') end |
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326 |
local offset = ((len-0xc0)*0x100) + self:byte () |
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327 |
remember = remember or self.offset |
|
328 |
self.offset = offset + 1 -- +1 for lua |
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329 |
else -- name is not compressed |
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330 |
append (n, self:sub (len)..'.') |
|
331 |
end |
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332 |
len = self:byte () |
|
333 |
end |
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334 |
self.offset = remember or self.offset |
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335 |
return table.concat (n) |
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336 |
end |
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337 |
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338 |
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339 |
function resolver:question () -- - - - - - - - - - - - - - - - - - question |
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340 |
local q = {} |
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341 |
q.name = self:name () |
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342 |
q.type = dns.type[self:word ()] |
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343 |
q.class = dns.type[self:word ()] |
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344 |
return q |
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345 |
end |
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346 |
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347 |
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348 |
function resolver:A (rr) -- - - - - - - - - - - - - - - - - - - - - - - - A |
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349 |
local b1, b2, b3, b4 = self:byte (4) |
|
350 |
rr.a = string.format ('%i.%i.%i.%i', b1, b2, b3, b4) |
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351 |
end |
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352 |
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353 |
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354 |
function resolver:CNAME (rr) -- - - - - - - - - - - - - - - - - - - - CNAME |
|
355 |
rr.cname = self:name () |
|
356 |
end |
|
357 |
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358 |
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359 |
function resolver:MX (rr) -- - - - - - - - - - - - - - - - - - - - - - - MX |
|
360 |
rr.pref = self:word () |
|
361 |
rr.mx = self:name () |
|
362 |
end |
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363 |
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364 |
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365 |
function resolver:LOC_nibble_power () -- - - - - - - - - - LOC_nibble_power |
|
366 |
local b = self:byte () |
|
367 |
-- print ('nibbles', ((b-(b%0x10))/0x10), (b%0x10)) |
|
368 |
return ((b-(b%0x10))/0x10) * (10^(b%0x10)) |
|
369 |
end |
|
370 |
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371 |
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372 |
function resolver:LOC (rr) -- - - - - - - - - - - - - - - - - - - - - - LOC |
|
373 |
rr.version = self:byte () |
|
374 |
if rr.version == 0 then |
|
375 |
rr.loc = rr.loc or {} |
|
376 |
rr.loc.size = self:LOC_nibble_power () |
|
377 |
rr.loc.horiz_pre = self:LOC_nibble_power () |
|
378 |
rr.loc.vert_pre = self:LOC_nibble_power () |
|
379 |
rr.loc.latitude = self:dword () |
|
380 |
rr.loc.longitude = self:dword () |
|
381 |
rr.loc.altitude = self:dword () |
|
382 |
end end |
|
383 |
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384 |
||
385 |
local function LOC_tostring_degrees (f, pos, neg) -- - - - - - - - - - - - - |
|
386 |
f = f - 0x80000000 |
|
387 |
if f < 0 then pos = neg f = -f end |
|
388 |
local deg, min, msec |
|
389 |
msec = f%60000 |
|
390 |
f = (f-msec)/60000 |
|
391 |
min = f%60 |
|
392 |
deg = (f-min)/60 |
|
393 |
return string.format ('%3d %2d %2.3f %s', deg, min, msec/1000, pos) |
|
394 |
end |
|
395 |
||
396 |
||
397 |
function resolver.LOC_tostring (rr) -- - - - - - - - - - - - - LOC_tostring |
|
398 |
||
399 |
local t = {} |
|
400 |
||
401 |
--[[ |
|
402 |
for k,name in pairs { 'size', 'horiz_pre', 'vert_pre', |
|
403 |
'latitude', 'longitude', 'altitude' } do |
|
404 |
append (t, string.format ('%4s%-10s: %12.0f\n', '', name, rr.loc[name])) |
|
405 |
end |
|
406 |
--]] |
|
407 |
||
408 |
append ( t, string.format ( |
|
409 |
'%s %s %.2fm %.2fm %.2fm %.2fm', |
|
410 |
LOC_tostring_degrees (rr.loc.latitude, 'N', 'S'), |
|
411 |
LOC_tostring_degrees (rr.loc.longitude, 'E', 'W'), |
|
412 |
(rr.loc.altitude - 10000000) / 100, |
|
413 |
rr.loc.size / 100, |
|
414 |
rr.loc.horiz_pre / 100, |
|
415 |
rr.loc.vert_pre / 100 ) ) |
|
416 |
||
417 |
return table.concat (t) |
|
418 |
end |
|
419 |
||
420 |
||
421 |
function resolver:NS (rr) -- - - - - - - - - - - - - - - - - - - - - - - NS |
|
422 |
rr.ns = self:name () |
|
423 |
end |
|
424 |
||
425 |
||
426 |
function resolver:SOA (rr) -- - - - - - - - - - - - - - - - - - - - - - SOA |
|
427 |
end |
|
428 |
||
429 |
||
430 |
function resolver:SRV (rr) -- - - - - - - - - - - - - - - - - - - - - - SRV |
|
431 |
rr.srv = {} |
|
432 |
rr.srv.priority = self:word () |
|
433 |
rr.srv.weight = self:word () |
|
434 |
rr.srv.port = self:word () |
|
435 |
rr.srv.target = self:name () |
|
436 |
end |
|
437 |
||
438 |
||
439 |
function SRV_tostring (rr) -- - - - - - - - - - - - - - - - - - SRV_tostring |
|
440 |
local s = rr.srv |
|
441 |
return string.format ( '%5d %5d %5d %s', |
|
442 |
s.priority, s.weight, s.port, s.target ) |
|
443 |
end |
|
444 |
||
445 |
||
446 |
function resolver:TXT (rr) -- - - - - - - - - - - - - - - - - - - - - - TXT |
|
447 |
rr.txt = self:sub (rr.rdlength) |
|
448 |
end |
|
449 |
||
450 |
||
451 |
function resolver:rr () -- - - - - - - - - - - - - - - - - - - - - - - - rr |
|
452 |
local rr = {} |
|
453 |
setmetatable (rr, rr_metatable) |
|
454 |
rr.name = self:name (self) |
|
455 |
rr.type = dns.type[self:word ()] or rr.type |
|
456 |
rr.class = dns.class[self:word ()] or rr.class |
|
457 |
rr.ttl = 0x10000*self:word () + self:word () |
|
458 |
rr.rdlength = self:word () |
|
459 |
||
460 |
if rr.ttl == 0 then -- pass |
|
461 |
else rr.tod = self.time + rr.ttl end |
|
462 |
||
463 |
local remember = self.offset |
|
464 |
local rr_parser = self[dns.type[rr.type]] |
|
465 |
if rr_parser then rr_parser (self, rr) end |
|
466 |
self.offset = remember |
|
467 |
rr.rdata = self:sub (rr.rdlength) |
|
468 |
return rr |
|
469 |
end |
|
470 |
||
471 |
||
472 |
function resolver:rrs (count) -- - - - - - - - - - - - - - - - - - - - - rrs |
|
473 |
local rrs = {} |
|
474 |
for i = 1,count do append (rrs, self:rr ()) end |
|
475 |
return rrs |
|
476 |
end |
|
477 |
||
478 |
||
479 |
function resolver:decode (packet, force) -- - - - - - - - - - - - - - decode |
|
480 |
||
481 |
self.packet, self.offset = packet, 1 |
|
482 |
local header = self:header (force) |
|
483 |
if not header then return nil end |
|
484 |
local response = { header = header } |
|
485 |
||
486 |
response.question = {} |
|
487 |
local offset = self.offset |
|
488 |
for i = 1,response.header.qdcount do |
|
489 |
append (response.question, self:question ()) end |
|
490 |
response.question.raw = string.sub (self.packet, offset, self.offset - 1) |
|
491 |
||
492 |
if not force then |
|
493 |
if not self.active[response.header.id] or |
|
494 |
not self.active[response.header.id][response.question.raw] then |
|
495 |
return nil end end |
|
496 |
||
497 |
response.answer = self:rrs (response.header.ancount) |
|
498 |
response.authority = self:rrs (response.header.nscount) |
|
499 |
response.additional = self:rrs (response.header.arcount) |
|
500 |
||
501 |
return response |
|
502 |
end |
|
503 |
||
504 |
||
505 |
-- socket layer -------------------------------------------------- socket layer |
|
506 |
||
507 |
||
508 |
resolver.delays = { 1, 3, 11, 45 } |
|
509 |
||
510 |
||
511 |
function resolver:addnameserver (address) -- - - - - - - - - - addnameserver |
|
512 |
self.server = self.server or {} |
|
513 |
append (self.server, address) |
|
514 |
end |
|
515 |
||
516 |
||
517 |
function resolver:setnameserver (address) -- - - - - - - - - - setnameserver |
|
518 |
self.server = {} |
|
519 |
self:addnameserver (address) |
|
520 |
end |
|
521 |
||
522 |
||
523 |
function resolver:adddefaultnameservers () -- - - - - adddefaultnameservers |
|
378
47fdbd074641
Fix dns for poor Windows users, who have never seen a resolv.conf
Matthew Wild <mwild1@gmail.com>
parents:
337
diff
changeset
|
524 |
local resolv_conf = io.open("/etc/resolv.conf"); |
399
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
525 |
if resolv_conf then |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
526 |
for line in resolv_conf:lines() do |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
527 |
local address = string.match (line, 'nameserver%s+(%d+%.%d+%.%d+%.%d+)') |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
528 |
if address then self:addnameserver (address) end |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
529 |
end |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
530 |
else -- FIXME correct for windows, using opendns nameservers for now |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
531 |
self:addnameserver ("208.67.222.222") |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
532 |
self:addnameserver ("208.67.220.220") |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
533 |
end |
93b6587d9afb
Added temporary fix for srv on windows: using opendns nameservers
Waqas Hussain <waqas20@gmail.com>
parents:
379
diff
changeset
|
534 |
end |
337 | 535 |
|
536 |
||
537 |
function resolver:getsocket (servernum) -- - - - - - - - - - - - - getsocket |
|
538 |
||
539 |
self.socket = self.socket or {} |
|
540 |
self.socketset = self.socketset or {} |
|
541 |
||
542 |
local sock = self.socket[servernum] |
|
543 |
if sock then return sock end |
|
544 |
||
545 |
sock = socket.udp () |
|
546 |
if self.socket_wrapper then sock = self.socket_wrapper (sock) end |
|
547 |
sock:settimeout (0) |
|
548 |
-- todo: attempt to use a random port, fallback to 0 |
|
549 |
sock:setsockname ('*', 0) |
|
550 |
sock:setpeername (self.server[servernum], 53) |
|
551 |
self.socket[servernum] = sock |
|
552 |
self.socketset[sock] = sock |
|
553 |
return sock |
|
554 |
end |
|
555 |
||
556 |
||
557 |
function resolver:socket_wrapper_set (func) -- - - - - - - socket_wrapper_set |
|
558 |
self.socket_wrapper = func |
|
559 |
end |
|
560 |
||
561 |
||
562 |
function resolver:closeall () -- - - - - - - - - - - - - - - - - - closeall |
|
563 |
for i,sock in ipairs (self.socket) do self.socket[i]:close () end |
|
564 |
self.socket = {} |
|
565 |
end |
|
566 |
||
567 |
||
568 |
function resolver:remember (rr, type) -- - - - - - - - - - - - - - remember |
|
569 |
||
570 |
-- print ('remember', type, rr.class, rr.type, rr.name) |
|
571 |
||
572 |
if type ~= '*' then |
|
573 |
type = rr.type |
|
574 |
local all = get (self.cache, rr.class, '*', rr.name) |
|
575 |
-- print ('remember all', all) |
|
576 |
if all then append (all, rr) end |
|
577 |
end |
|
578 |
||
579 |
self.cache = self.cache or setmetatable ({}, cache_metatable) |
|
580 |
local rrs = get (self.cache, rr.class, type, rr.name) or |
|
581 |
set (self.cache, rr.class, type, rr.name, setmetatable ({}, rrs_metatable)) |
|
582 |
append (rrs, rr) |
|
583 |
||
584 |
if type == 'MX' then self.unsorted[rrs] = true end |
|
585 |
end |
|
586 |
||
587 |
||
588 |
local function comp_mx (a, b) -- - - - - - - - - - - - - - - - - - - comp_mx |
|
589 |
return (a.pref == b.pref) and (a.mx < b.mx) or (a.pref < b.pref) |
|
590 |
end |
|
591 |
||
592 |
||
593 |
function resolver:peek (qname, qtype, qclass) -- - - - - - - - - - - - peek |
|
594 |
qname, qtype, qclass = standardize (qname, qtype, qclass) |
|
595 |
local rrs = get (self.cache, qclass, qtype, qname) |
|
596 |
if not rrs then return nil end |
|
597 |
if prune (rrs, socket.gettime ()) and qtype == '*' or not next (rrs) then |
|
598 |
set (self.cache, qclass, qtype, qname, nil) return nil end |
|
599 |
if self.unsorted[rrs] then table.sort (rrs, comp_mx) end |
|
600 |
return rrs |
|
601 |
end |
|
602 |
||
603 |
||
604 |
function resolver:purge (soft) -- - - - - - - - - - - - - - - - - - - purge |
|
605 |
if soft == 'soft' then |
|
606 |
self.time = socket.gettime () |
|
607 |
for class,types in pairs (self.cache or {}) do |
|
608 |
for type,names in pairs (types) do |
|
609 |
for name,rrs in pairs (names) do |
|
379
c5617678cd7b
Fix various mistakes in dns.lua
Matthew Wild <mwild1@gmail.com>
parents:
378
diff
changeset
|
610 |
prune (rrs, self.time, 'soft') |
337 | 611 |
end end end |
612 |
else self.cache = {} end |
|
613 |
end |
|
614 |
||
615 |
||
616 |
function resolver:query (qname, qtype, qclass) -- - - - - - - - - - -- query |
|
617 |
||
618 |
qname, qtype, qclass = standardize (qname, qtype, qclass) |
|
619 |
||
620 |
if not self.server then self:adddefaultnameservers () end |
|
621 |
||
379
c5617678cd7b
Fix various mistakes in dns.lua
Matthew Wild <mwild1@gmail.com>
parents:
378
diff
changeset
|
622 |
local question = encodeQuestion (qname, qtype, qclass) |
337 | 623 |
local peek = self:peek (qname, qtype, qclass) |
624 |
if peek then return peek end |
|
625 |
||
626 |
local header, id = encodeHeader () |
|
627 |
-- print ('query id', id, qclass, qtype, qname) |
|
628 |
local o = { packet = header..question, |
|
629 |
server = 1, |
|
630 |
delay = 1, |
|
631 |
retry = socket.gettime () + self.delays[1] } |
|
632 |
self:getsocket (o.server):send (o.packet) |
|
633 |
||
634 |
-- remember the query |
|
635 |
self.active[id] = self.active[id] or {} |
|
636 |
self.active[id][question] = o |
|
637 |
||
638 |
-- remember which coroutine wants the answer |
|
639 |
local co = coroutine.running () |
|
640 |
if co then |
|
641 |
set (self.wanted, qclass, qtype, qname, co, true) |
|
642 |
set (self.yielded, co, qclass, qtype, qname, true) |
|
643 |
end end |
|
644 |
||
645 |
||
646 |
function resolver:receive (rset) -- - - - - - - - - - - - - - - - - receive |
|
647 |
||
648 |
-- print 'receive' print (self.socket) |
|
649 |
self.time = socket.gettime () |
|
650 |
rset = rset or self.socket |
|
651 |
||
652 |
local response |
|
653 |
for i,sock in pairs (rset) do |
|
654 |
||
655 |
if self.socketset[sock] then |
|
656 |
local packet = sock:receive () |
|
657 |
if packet then |
|
658 |
||
659 |
response = self:decode (packet) |
|
660 |
if response then |
|
661 |
-- print 'received response' |
|
662 |
-- self.print (response) |
|
663 |
||
664 |
for i,section in pairs { 'answer', 'authority', 'additional' } do |
|
665 |
for j,rr in pairs (response[section]) do |
|
666 |
self:remember (rr, response.question[1].type) end end |
|
667 |
||
668 |
-- retire the query |
|
669 |
local queries = self.active[response.header.id] |
|
670 |
if queries[response.question.raw] then |
|
671 |
queries[response.question.raw] = nil end |
|
672 |
if not next (queries) then self.active[response.header.id] = nil end |
|
673 |
if not next (self.active) then self:closeall () end |
|
674 |
||
675 |
-- was the query on the wanted list? |
|
676 |
local q = response.question |
|
677 |
local cos = get (self.wanted, q.class, q.type, q.name) |
|
678 |
if cos then |
|
679 |
for co in pairs (cos) do |
|
680 |
set (self.yielded, co, q.class, q.type, q.name, nil) |
|
681 |
if not self.yielded[co] then coroutine.resume (co) end |
|
682 |
end |
|
683 |
set (self.wanted, q.class, q.type, q.name, nil) |
|
684 |
end end end end end |
|
685 |
||
686 |
return response |
|
687 |
end |
|
688 |
||
689 |
||
690 |
function resolver:pulse () -- - - - - - - - - - - - - - - - - - - - - pulse |
|
691 |
||
692 |
-- print ':pulse' |
|
693 |
while self:receive () do end |
|
694 |
if not next (self.active) then return nil end |
|
695 |
||
696 |
self.time = socket.gettime () |
|
697 |
for id,queries in pairs (self.active) do |
|
698 |
for question,o in pairs (queries) do |
|
699 |
if self.time >= o.retry then |
|
700 |
||
701 |
o.server = o.server + 1 |
|
702 |
if o.server > #self.server then |
|
703 |
o.server = 1 |
|
704 |
o.delay = o.delay + 1 |
|
705 |
end |
|
706 |
||
707 |
if o.delay > #self.delays then |
|
708 |
print ('timeout') |
|
709 |
queries[question] = nil |
|
710 |
if not next (queries) then self.active[id] = nil end |
|
711 |
if not next (self.active) then return nil end |
|
712 |
else |
|
713 |
-- print ('retry', o.server, o.delay) |
|
453
a1efb2cb4f9c
Quickfix for dns.lua to not crash on failed connection to name servers
Waqas Hussain <waqas20@gmail.com>
parents:
399
diff
changeset
|
714 |
local _a = self.socket[o.server]; |
a1efb2cb4f9c
Quickfix for dns.lua to not crash on failed connection to name servers
Waqas Hussain <waqas20@gmail.com>
parents:
399
diff
changeset
|
715 |
if _a then _a:send (o.packet) end |
337 | 716 |
o.retry = self.time + self.delays[o.delay] |
717 |
end end end end |
|
718 |
||
719 |
if next (self.active) then return true end |
|
720 |
return nil |
|
721 |
end |
|
722 |
||
723 |
||
724 |
function resolver:lookup (qname, qtype, qclass) -- - - - - - - - - - lookup |
|
725 |
self:query (qname, qtype, qclass) |
|
726 |
while self:pulse () do socket.select (self.socket, nil, 4) end |
|
727 |
-- print (self.cache) |
|
728 |
return self:peek (qname, qtype, qclass) |
|
729 |
end |
|
730 |
||
731 |
||
732 |
-- print ---------------------------------------------------------------- print |
|
733 |
||
734 |
||
735 |
local hints = { -- - - - - - - - - - - - - - - - - - - - - - - - - - - hints |
|
736 |
qr = { [0]='query', 'response' }, |
|
737 |
opcode = { [0]='query', 'inverse query', 'server status request' }, |
|
738 |
aa = { [0]='non-authoritative', 'authoritative' }, |
|
739 |
tc = { [0]='complete', 'truncated' }, |
|
740 |
rd = { [0]='recursion not desired', 'recursion desired' }, |
|
741 |
ra = { [0]='recursion not available', 'recursion available' }, |
|
742 |
z = { [0]='(reserved)' }, |
|
743 |
rcode = { [0]='no error', 'format error', 'server failure', 'name error', |
|
744 |
'not implemented' }, |
|
745 |
||
746 |
type = dns.type, |
|
747 |
class = dns.class, } |
|
748 |
||
749 |
||
750 |
local function hint (p, s) -- - - - - - - - - - - - - - - - - - - - - - hint |
|
751 |
return (hints[s] and hints[s][p[s]]) or '' end |
|
752 |
||
753 |
||
754 |
function resolver.print (response) -- - - - - - - - - - - - - resolver.print |
|
755 |
||
756 |
for s,s in pairs { 'id', 'qr', 'opcode', 'aa', 'tc', 'rd', 'ra', 'z', |
|
757 |
'rcode', 'qdcount', 'ancount', 'nscount', 'arcount' } do |
|
758 |
print ( string.format ('%-30s', 'header.'..s), |
|
759 |
response.header[s], hint (response.header, s) ) |
|
760 |
end |
|
761 |
||
762 |
for i,question in ipairs (response.question) do |
|
763 |
print (string.format ('question[%i].name ', i), question.name) |
|
764 |
print (string.format ('question[%i].type ', i), question.type) |
|
765 |
print (string.format ('question[%i].class ', i), question.class) |
|
766 |
end |
|
767 |
||
768 |
local common = { name=1, type=1, class=1, ttl=1, rdlength=1, rdata=1 } |
|
769 |
local tmp |
|
770 |
for s,s in pairs {'answer', 'authority', 'additional'} do |
|
771 |
for i,rr in pairs (response[s]) do |
|
772 |
for j,t in pairs { 'name', 'type', 'class', 'ttl', 'rdlength' } do |
|
773 |
tmp = string.format ('%s[%i].%s', s, i, t) |
|
774 |
print (string.format ('%-30s', tmp), rr[t], hint (rr, t)) |
|
775 |
end |
|
776 |
for j,t in pairs (rr) do |
|
777 |
if not common[j] then |
|
778 |
tmp = string.format ('%s[%i].%s', s, i, j) |
|
779 |
print (string.format ('%-30s %s', tmp, t)) |
|
780 |
end end end end end |
|
781 |
||
782 |
||
783 |
-- module api ------------------------------------------------------ module api |
|
784 |
||
785 |
||
786 |
local function resolve (func, ...) -- - - - - - - - - - - - - - resolver_get |
|
787 |
dns._resolver = dns._resolver or dns.resolver () |
|
788 |
return func (dns._resolver, ...) |
|
789 |
end |
|
790 |
||
791 |
||
792 |
function dns.resolver () -- - - - - - - - - - - - - - - - - - - - - resolver |
|
793 |
||
794 |
-- this function seems to be redundant with resolver.new () |
|
795 |
||
379
c5617678cd7b
Fix various mistakes in dns.lua
Matthew Wild <mwild1@gmail.com>
parents:
378
diff
changeset
|
796 |
local r = { active = {}, cache = {}, unsorted = {}, wanted = {}, yielded = {} } |
337 | 797 |
setmetatable (r, resolver) |
798 |
setmetatable (r.cache, cache_metatable) |
|
799 |
setmetatable (r.unsorted, { __mode = 'kv' }) |
|
800 |
return r |
|
801 |
end |
|
802 |
||
803 |
||
804 |
function dns.lookup (...) -- - - - - - - - - - - - - - - - - - - - - lookup |
|
805 |
return resolve (resolver.lookup, ...) end |
|
806 |
||
807 |
||
808 |
function dns.purge (...) -- - - - - - - - - - - - - - - - - - - - - - purge |
|
809 |
return resolve (resolver.purge, ...) end |
|
810 |
||
811 |
function dns.peek (...) -- - - - - - - - - - - - - - - - - - - - - - - peek |
|
812 |
return resolve (resolver.peek, ...) end |
|
813 |
||
814 |
||
815 |
function dns.query (...) -- - - - - - - - - - - - - - - - - - - - - - query |
|
816 |
return resolve (resolver.query, ...) end |
|
817 |
||
818 |
||
819 |
function dns:socket_wrapper_set (...) -- - - - - - - - - socket_wrapper_set |
|
820 |
return resolve (resolver.socket_wrapper_set, ...) end |
|
821 |
||
822 |
||
823 |
return dns |