mirror of
https://github.com/bjc/prosody.git
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We have SRV resolving \o/
This commit is contained in:
Matthew Wild
parent
d73e81900b
commit
801e99fcbb
4 changed files with 1188 additions and 6 deletions
795
net/dns.lua
Normal file
795
net/dns.lua
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@ -0,0 +1,795 @@
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-- public domain 20080404 lua@ztact.com
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-- 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 =
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ipairs, next, pairs, print, setmetatable, tostring
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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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-- dns type & class codes ------------------------------ dns type & class codes
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local append = table.insert
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local function highbyte (i) -- - - - - - - - - - - - - - - - - - - highbyte
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return (i-(i%0x100))/0x100
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end
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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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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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local function prune (rrs, time, soft) -- - - - - - - - - - - - - - - prune
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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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-- 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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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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end
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local rrs_metatable = {} -- - - - - - - - - - - - - - - - - - rrs_metatable
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function rrs_metatable.__tostring (rrs)
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t = {}
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for i,rr in pairs (rrs) do append (t, tostring (rr)..'\n') end
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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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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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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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for k,v in pairs (h) do h[k] = v-v%1 end
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return h
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end
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function resolver:name () -- - - - - - - - - - - - - - - - - - - - - - name
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local remember, pointers = nil, 0
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local len = self:byte ()
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local n = {}
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while len > 0 do
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if len >= 0xc0 then -- name is "compressed"
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pointers = pointers + 1
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if pointers >= 20 then error ('dns error: 20 pointers') end
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local offset = ((len-0xc0)*0x100) + self:byte ()
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remember = remember or self.offset
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self.offset = offset + 1 -- +1 for lua
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else -- name is not compressed
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append (n, self:sub (len)..'.')
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end
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len = self:byte ()
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end
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self.offset = remember or self.offset
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return table.concat (n)
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end
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function resolver:question () -- - - - - - - - - - - - - - - - - - question
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local q = {}
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q.name = self:name ()
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q.type = dns.type[self:word ()]
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q.class = dns.type[self:word ()]
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return q
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end
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function resolver:A (rr) -- - - - - - - - - - - - - - - - - - - - - - - - A
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local b1, b2, b3, b4 = self:byte (4)
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rr.a = string.format ('%i.%i.%i.%i', b1, b2, b3, b4)
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end
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function resolver:CNAME (rr) -- - - - - - - - - - - - - - - - - - - - CNAME
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rr.cname = self:name ()
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end
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function resolver:MX (rr) -- - - - - - - - - - - - - - - - - - - - - - - MX
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rr.pref = self:word ()
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rr.mx = self:name ()
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end
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function resolver:LOC_nibble_power () -- - - - - - - - - - LOC_nibble_power
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local b = self:byte ()
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-- print ('nibbles', ((b-(b%0x10))/0x10), (b%0x10))
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return ((b-(b%0x10))/0x10) * (10^(b%0x10))
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end
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function resolver:LOC (rr) -- - - - - - - - - - - - - - - - - - - - - - LOC
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rr.version = self:byte ()
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if rr.version == 0 then
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rr.loc = rr.loc or {}
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rr.loc.size = self:LOC_nibble_power ()
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rr.loc.horiz_pre = self:LOC_nibble_power ()
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rr.loc.vert_pre = self:LOC_nibble_power ()
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rr.loc.latitude = self:dword ()
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rr.loc.longitude = self:dword ()
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rr.loc.altitude = self:dword ()
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end end
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local function LOC_tostring_degrees (f, pos, neg) -- - - - - - - - - - - - -
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f = f - 0x80000000
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if f < 0 then pos = neg f = -f end
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local deg, min, msec
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msec = f%60000
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f = (f-msec)/60000
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min = f%60
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deg = (f-min)/60
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return string.format ('%3d %2d %2.3f %s', deg, min, msec/1000, pos)
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end
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function resolver.LOC_tostring (rr) -- - - - - - - - - - - - - LOC_tostring
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local t = {}
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--[[
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for k,name in pairs { 'size', 'horiz_pre', 'vert_pre',
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'latitude', 'longitude', 'altitude' } do
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append (t, string.format ('%4s%-10s: %12.0f\n', '', name, rr.loc[name]))
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end
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--]]
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append ( t, string.format (
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'%s %s %.2fm %.2fm %.2fm %.2fm',
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LOC_tostring_degrees (rr.loc.latitude, 'N', 'S'),
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LOC_tostring_degrees (rr.loc.longitude, 'E', 'W'),
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(rr.loc.altitude - 10000000) / 100,
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rr.loc.size / 100,
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rr.loc.horiz_pre / 100,
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rr.loc.vert_pre / 100 ) )
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return table.concat (t)
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end
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function resolver:NS (rr) -- - - - - - - - - - - - - - - - - - - - - - - NS
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rr.ns = self:name ()
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end
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function resolver:SOA (rr) -- - - - - - - - - - - - - - - - - - - - - - SOA
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end
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function resolver:SRV (rr) -- - - - - - - - - - - - - - - - - - - - - - SRV
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rr.srv = {}
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rr.srv.priority = self:word ()
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rr.srv.weight = self:word ()
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rr.srv.port = self:word ()
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rr.srv.target = self:name ()
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end
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function SRV_tostring (rr) -- - - - - - - - - - - - - - - - - - SRV_tostring
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local s = rr.srv
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return string.format ( '%5d %5d %5d %s',
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s.priority, s.weight, s.port, s.target )
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end
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function resolver:TXT (rr) -- - - - - - - - - - - - - - - - - - - - - - TXT
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rr.txt = self:sub (rr.rdlength)
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end
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function resolver:rr () -- - - - - - - - - - - - - - - - - - - - - - - - rr
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local rr = {}
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setmetatable (rr, rr_metatable)
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rr.name = self:name (self)
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rr.type = dns.type[self:word ()] or rr.type
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rr.class = dns.class[self:word ()] or rr.class
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rr.ttl = 0x10000*self:word () + self:word ()
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rr.rdlength = self:word ()
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if rr.ttl == 0 then -- pass
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else rr.tod = self.time + rr.ttl end
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local remember = self.offset
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local rr_parser = self[dns.type[rr.type]]
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if rr_parser then rr_parser (self, rr) end
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self.offset = remember
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rr.rdata = self:sub (rr.rdlength)
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return rr
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end
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function resolver:rrs (count) -- - - - - - - - - - - - - - - - - - - - - rrs
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local rrs = {}
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for i = 1,count do append (rrs, self:rr ()) end
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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
|
||||
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
|
||||
|
||||
|
||||
-- socket layer -------------------------------------------------- socket layer
|
||||
|
||||
|
||||
resolver.delays = { 1, 3, 11, 45 }
|
||||
|
||||
|
||||
function resolver:addnameserver (address) -- - - - - - - - - - addnameserver
|
||||
self.server = self.server or {}
|
||||
append (self.server, address)
|
||||
end
|
||||
|
||||
|
||||
function resolver:setnameserver (address) -- - - - - - - - - - setnameserver
|
||||
self.server = {}
|
||||
self:addnameserver (address)
|
||||
end
|
||||
|
||||
|
||||
function resolver:adddefaultnameservers () -- - - - - adddefaultnameservers
|
||||
for line in io.lines ('/etc/resolv.conf') do
|
||||
address = string.match (line, 'nameserver%s+(%d+%.%d+%.%d+%.%d+)')
|
||||
if address then self:addnameserver (address) end
|
||||
end end
|
||||
|
||||
|
||||
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
|
||||
|
||||
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
|
||||
|
||||
|
||||
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
|
||||
|
||||
|
||||
function resolver:remember (rr, type) -- - - - - - - - - - - - - - remember
|
||||
|
||||
-- print ('remember', type, rr.class, rr.type, rr.name)
|
||||
|
||||
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
|
||||
|
||||
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)
|
||||
|
||||
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
|
||||
|
||||
|
||||
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, 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 = question or 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 not self.yielded[co] 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: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)
|
||||
self.socket[o.server]:send (o.packet)
|
||||
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 socket.select (self.socket, nil, 4) end
|
||||
-- print (self.cache)
|
||||
return self:peek (qname, qtype, qclass)
|
||||
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', tmp, t))
|
||||
end end end end end
|
||||
|
||||
|
||||
-- module api ------------------------------------------------------ module api
|
||||
|
||||
|
||||
local function resolve (func, ...) -- - - - - - - - - - - - - - resolver_get
|
||||
dns._resolver = dns._resolver or dns.resolver ()
|
||||
return func (dns._resolver, ...)
|
||||
end
|
||||
|
||||
|
||||
function dns.resolver () -- - - - - - - - - - - - - - - - - - - - - resolver
|
||||
|
||||
-- this function seems to be redundant with resolver.new ()
|
||||
|
||||
r = { active = {}, cache = {}, unsorted = {}, wanted = {}, yielded = {} }
|
||||
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
|
||||
|
||||
|
||||
function dns.purge (...) -- - - - - - - - - - - - - - - - - - - - - - purge
|
||||
return resolve (resolver.purge, ...) end
|
||||
|
||||
function dns.peek (...) -- - - - - - - - - - - - - - - - - - - - - - - peek
|
||||
return resolve (resolver.peek, ...) end
|
||||
|
||||
|
||||
function dns.query (...) -- - - - - - - - - - - - - - - - - - - - - - query
|
||||
return resolve (resolver.query, ...) end
|
||||
|
||||
|
||||
function dns:socket_wrapper_set (...) -- - - - - - - - - socket_wrapper_set
|
||||
return resolve (resolver.socket_wrapper_set, ...) end
|
||||
|
||||
|
||||
return dns
|
||||
Loading…
Add table
Add a link
Reference in a new issue