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Diffstat (limited to 'trunk/lib/resolv.rb')
| -rw-r--r-- | trunk/lib/resolv.rb | 2262 |
1 files changed, 2262 insertions, 0 deletions
diff --git a/trunk/lib/resolv.rb b/trunk/lib/resolv.rb new file mode 100644 index 0000000000..d1494b46c9 --- /dev/null +++ b/trunk/lib/resolv.rb @@ -0,0 +1,2262 @@ +require 'socket' +require 'fcntl' +require 'timeout' +require 'thread' + +begin + require 'securerandom' +rescue LoadError +end + +# Resolv is a thread-aware DNS resolver library written in Ruby. Resolv can +# handle multiple DNS requests concurrently without blocking. The ruby +# interpreter. +# +# See also resolv-replace.rb to replace the libc resolver with # Resolv. +# +# Resolv can look up various DNS resources using the DNS module directly. +# +# Examples: +# +# p Resolv.getaddress "www.ruby-lang.org" +# p Resolv.getname "210.251.121.214" +# +# Resolv::DNS.open do |dns| +# ress = dns.getresources "www.ruby-lang.org", Resolv::DNS::Resource::IN::A +# p ress.map { |r| r.address } +# ress = dns.getresources "ruby-lang.org", Resolv::DNS::Resource::IN::MX +# p ress.map { |r| [r.exchange.to_s, r.preference] } +# end +# +# +# == Bugs +# +# * NIS is not supported. +# * /etc/nsswitch.conf is not supported. + +class Resolv + + ## + # Looks up the first IP address for +name+. + + def self.getaddress(name) + DefaultResolver.getaddress(name) + end + + ## + # Looks up all IP address for +name+. + + def self.getaddresses(name) + DefaultResolver.getaddresses(name) + end + + ## + # Iterates over all IP addresses for +name+. + + def self.each_address(name, &block) + DefaultResolver.each_address(name, &block) + end + + ## + # Looks up the hostname of +address+. + + def self.getname(address) + DefaultResolver.getname(address) + end + + ## + # Looks up all hostnames for +address+. + + def self.getnames(address) + DefaultResolver.getnames(address) + end + + ## + # Iterates over all hostnames for +address+. + + def self.each_name(address, &proc) + DefaultResolver.each_name(address, &proc) + end + + ## + # Creates a new Resolv using +resolvers+. + + def initialize(resolvers=[Hosts.new, DNS.new]) + @resolvers = resolvers + end + + ## + # Looks up the first IP address for +name+. + + def getaddress(name) + each_address(name) {|address| return address} + raise ResolvError.new("no address for #{name}") + end + + ## + # Looks up all IP address for +name+. + + def getaddresses(name) + ret = [] + each_address(name) {|address| ret << address} + return ret + end + + ## + # Iterates over all IP addresses for +name+. + + def each_address(name) + if AddressRegex =~ name + yield name + return + end + yielded = false + @resolvers.each {|r| + r.each_address(name) {|address| + yield address.to_s + yielded = true + } + return if yielded + } + end + + ## + # Looks up the hostname of +address+. + + def getname(address) + each_name(address) {|name| return name} + raise ResolvError.new("no name for #{address}") + end + + ## + # Looks up all hostnames for +address+. + + def getnames(address) + ret = [] + each_name(address) {|name| ret << name} + return ret + end + + ## + # Iterates over all hostnames for +address+. + + def each_name(address) + yielded = false + @resolvers.each {|r| + r.each_name(address) {|name| + yield name.to_s + yielded = true + } + return if yielded + } + end + + ## + # Indicates a failure to resolve a name or address. + + class ResolvError < StandardError; end + + ## + # Indicates a timeout resolving a name or address. + + class ResolvTimeout < TimeoutError; end + + ## + # DNS::Hosts is a hostname resolver that uses the system hosts file. + + class Hosts + if /mswin32|mingw|bccwin/ =~ RUBY_PLATFORM + require 'win32/resolv' + DefaultFileName = Win32::Resolv.get_hosts_path + else + DefaultFileName = '/etc/hosts' + end + + ## + # Creates a new DNS::Hosts, using +filename+ for its data source. + + def initialize(filename = DefaultFileName) + @filename = filename + @mutex = Mutex.new + @initialized = nil + end + + def lazy_initialize # :nodoc: + @mutex.synchronize { + unless @initialized + @name2addr = {} + @addr2name = {} + open(@filename) {|f| + f.each {|line| + line.sub!(/#.*/, '') + addr, hostname, *aliases = line.split(/\s+/) + next unless addr + addr.untaint + hostname.untaint + @addr2name[addr] = [] unless @addr2name.include? addr + @addr2name[addr] << hostname + @addr2name[addr] += aliases + @name2addr[hostname] = [] unless @name2addr.include? hostname + @name2addr[hostname] << addr + aliases.each {|n| + n.untaint + @name2addr[n] = [] unless @name2addr.include? n + @name2addr[n] << addr + } + } + } + @name2addr.each {|name, arr| arr.reverse!} + @initialized = true + end + } + self + end + + ## + # Gets the IP address of +name+ from the hosts file. + + def getaddress(name) + each_address(name) {|address| return address} + raise ResolvError.new("#{@filename} has no name: #{name}") + end + + ## + # Gets all IP addresses for +name+ from the hosts file. + + def getaddresses(name) + ret = [] + each_address(name) {|address| ret << address} + return ret + end + + ## + # Iterates over all IP addresses for +name+ retrieved from the hosts file. + + def each_address(name, &proc) + lazy_initialize + if @name2addr.include?(name) + @name2addr[name].each(&proc) + end + end + + ## + # Gets the hostname of +address+ from the hosts file. + + def getname(address) + each_name(address) {|name| return name} + raise ResolvError.new("#{@filename} has no address: #{address}") + end + + ## + # Gets all hostnames for +address+ from the hosts file. + + def getnames(address) + ret = [] + each_name(address) {|name| ret << name} + return ret + end + + ## + # Iterates over all hostnames for +address+ retrieved from the hosts file. + + def each_name(address, &proc) + lazy_initialize + if @addr2name.include?(address) + @addr2name[address].each(&proc) + end + end + end + + ## + # Resolv::DNS is a DNS stub resolver. + # + # Information taken from the following places: + # + # * STD0013 + # * RFC 1035 + # * ftp://ftp.isi.edu/in-notes/iana/assignments/dns-parameters + # * etc. + + class DNS + + ## + # Default DNS Port + + Port = 53 + + ## + # Default DNS UDP packet size + + UDPSize = 512 + + ## + # Creates a new DNS resolver. See Resolv::DNS.new for argument details. + # + # Yields the created DNS resolver to the block, if given, otherwise + # returns it. + + def self.open(*args) + dns = new(*args) + return dns unless block_given? + begin + yield dns + ensure + dns.close + end + end + + ## + # Creates a new DNS resolver. + # + # +config_info+ can be: + # + # nil:: Uses /etc/resolv.conf. + # String:: Path to a file using /etc/resolv.conf's format. + # Hash:: Must contain :nameserver, :search and :ndots keys. + # + # Example: + # + # Resolv::DNS.new(:nameserver => ['210.251.121.21'], + # :search => ['ruby-lang.org'], + # :ndots => 1) + + def initialize(config_info=nil) + @mutex = Mutex.new + @config = Config.new(config_info) + @initialized = nil + end + + def lazy_initialize # :nodoc: + @mutex.synchronize { + unless @initialized + @config.lazy_initialize + @initialized = true + end + } + self + end + + ## + # Closes the DNS resolver. + + def close + @mutex.synchronize { + if @initialized + @initialized = false + end + } + end + + ## + # Gets the IP address of +name+ from the DNS resolver. + # + # +name+ can be a Resolv::DNS::Name or a String. Retrieved address will + # be a Resolv::IPv4 or Resolv::IPv6 + + def getaddress(name) + each_address(name) {|address| return address} + raise ResolvError.new("DNS result has no information for #{name}") + end + + ## + # Gets all IP addresses for +name+ from the DNS resolver. + # + # +name+ can be a Resolv::DNS::Name or a String. Retrieved addresses will + # be a Resolv::IPv4 or Resolv::IPv6 + + def getaddresses(name) + ret = [] + each_address(name) {|address| ret << address} + return ret + end + + ## + # Iterates over all IP addresses for +name+ retrieved from the DNS + # resolver. + # + # +name+ can be a Resolv::DNS::Name or a String. Retrieved addresses will + # be a Resolv::IPv4 or Resolv::IPv6 + + def each_address(name) + each_resource(name, Resource::IN::A) {|resource| yield resource.address} + each_resource(name, Resource::IN::AAAA) {|resource| yield resource.address} + end + + ## + # Gets the hostname for +address+ from the DNS resolver. + # + # +address+ must be a Resolv::IPv4, Resolv::IPv6 or a String. Retrieved + # name will be a Resolv::DNS::Name. + + def getname(address) + each_name(address) {|name| return name} + raise ResolvError.new("DNS result has no information for #{address}") + end + + ## + # Gets all hostnames for +address+ from the DNS resolver. + # + # +address+ must be a Resolv::IPv4, Resolv::IPv6 or a String. Retrieved + # names will be Resolv::DNS::Name instances. + + def getnames(address) + ret = [] + each_name(address) {|name| ret << name} + return ret + end + + ## + # Iterates over all hostnames for +address+ retrieved from the DNS + # resolver. + # + # +address+ must be a Resolv::IPv4, Resolv::IPv6 or a String. Retrieved + # names will be Resolv::DNS::Name instances. + + def each_name(address) + case address + when Name + ptr = address + when IPv4::Regex + ptr = IPv4.create(address).to_name + when IPv6::Regex + ptr = IPv6.create(address).to_name + else + raise ResolvError.new("cannot interpret as address: #{address}") + end + each_resource(ptr, Resource::IN::PTR) {|resource| yield resource.name} + end + + ## + # Look up the +typeclass+ DNS resource of +name+. + # + # +name+ must be a Resolv::DNS::Name or a String. + # + # +typeclass+ should be one of the following: + # + # * Resolv::DNS::Resource::IN::A + # * Resolv::DNS::Resource::IN::AAAA + # * Resolv::DNS::Resource::IN::ANY + # * Resolv::DNS::Resource::IN::CNAME + # * Resolv::DNS::Resource::IN::HINFO + # * Resolv::DNS::Resource::IN::MINFO + # * Resolv::DNS::Resource::IN::MX + # * Resolv::DNS::Resource::IN::NS + # * Resolv::DNS::Resource::IN::PTR + # * Resolv::DNS::Resource::IN::SOA + # * Resolv::DNS::Resource::IN::TXT + # * Resolv::DNS::Resource::IN::WKS + # + # Returned resource is represented as a Resolv::DNS::Resource instance, + # i.e. Resolv::DNS::Resource::IN::A. + + def getresource(name, typeclass) + each_resource(name, typeclass) {|resource| return resource} + raise ResolvError.new("DNS result has no information for #{name}") + end + + ## + # Looks up all +typeclass+ DNS resources for +name+. See #getresource for + # argument details. + + def getresources(name, typeclass) + ret = [] + each_resource(name, typeclass) {|resource| ret << resource} + return ret + end + + ## + # Iterates over all +typeclass+ DNS resources for +name+. See + # #getresource for argument details. + + def each_resource(name, typeclass, &proc) + lazy_initialize + requester = make_requester + senders = {} + begin + @config.resolv(name) {|candidate, tout, nameserver| + msg = Message.new + msg.rd = 1 + msg.add_question(candidate, typeclass) + unless sender = senders[[candidate, nameserver]] + sender = senders[[candidate, nameserver]] = + requester.sender(msg, candidate, nameserver) + end + reply, reply_name = requester.request(sender, tout) + case reply.rcode + when RCode::NoError + extract_resources(reply, reply_name, typeclass, &proc) + return + when RCode::NXDomain + raise Config::NXDomain.new(reply_name.to_s) + else + raise Config::OtherResolvError.new(reply_name.to_s) + end + } + ensure + requester.close + end + end + + def make_requester # :nodoc: + if nameserver = @config.single? + Requester::ConnectedUDP.new(nameserver) + else + Requester::UnconnectedUDP.new + end + end + + def extract_resources(msg, name, typeclass) # :nodoc: + if typeclass < Resource::ANY + n0 = Name.create(name) + msg.each_answer {|n, ttl, data| + yield data if n0 == n + } + end + yielded = false + n0 = Name.create(name) + msg.each_answer {|n, ttl, data| + if n0 == n + case data + when typeclass + yield data + yielded = true + when Resource::CNAME + n0 = data.name + end + end + } + return if yielded + msg.each_answer {|n, ttl, data| + if n0 == n + case data + when typeclass + yield data + end + end + } + end + + if defined? SecureRandom + def self.random(arg) # :nodoc: + begin + SecureRandom.random_number(arg) + rescue NotImplementedError + rand(arg) + end + end + else + def self.random(arg) # :nodoc: + rand(arg) + end + end + + + def self.rangerand(range) # :nodoc: + base = range.begin + len = range.end - range.begin + if !range.exclude_end? + len += 1 + end + base + random(len) + end + + RequestID = {} + RequestIDMutex = Mutex.new + + def self.allocate_request_id(host, port) # :nodoc: + id = nil + RequestIDMutex.synchronize { + h = (RequestID[[host, port]] ||= {}) + begin + id = rangerand(0x0000..0xffff) + end while h[id] + h[id] = true + } + id + end + + def self.free_request_id(host, port, id) # :nodoc: + RequestIDMutex.synchronize { + key = [host, port] + if h = RequestID[key] + h.delete id + if h.empty? + RequestID.delete key + end + end + } + end + + def self.bind_random_port(udpsock) # :nodoc: + begin + port = rangerand(1024..65535) + udpsock.bind("", port) + rescue Errno::EADDRINUSE + retry + end + end + + class Requester # :nodoc: + def initialize + @senders = {} + @sock = nil + end + + def request(sender, tout) + timelimit = Time.now + tout + sender.send + while (now = Time.now) < timelimit + timeout = timelimit - now + if !IO.select([@sock], nil, nil, timeout) + raise ResolvTimeout + end + reply, from = recv_reply + begin + msg = Message.decode(reply) + rescue DecodeError + next # broken DNS message ignored + end + if s = @senders[[from,msg.id]] + break + else + # unexpected DNS message ignored + end + end + return msg, s.data + end + + def close + sock = @sock + @sock = nil + sock.close if sock + end + + class Sender # :nodoc: + def initialize(msg, data, sock) + @msg = msg + @data = data + @sock = sock + end + end + + class UnconnectedUDP < Requester # :nodoc: + def initialize + super() + @sock = UDPSocket.new + @sock.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC) if defined? Fcntl::F_SETFD + DNS.bind_random_port(@sock) + end + + def recv_reply + reply, from = @sock.recvfrom(UDPSize) + return reply, [from[3],from[1]] + end + + def sender(msg, data, host, port=Port) + service = [host, port] + id = DNS.allocate_request_id(host, port) + request = msg.encode + request[0,2] = [id].pack('n') + return @senders[[service, id]] = + Sender.new(request, data, @sock, host, port) + end + + def close + super + @senders.each_key {|service, id| + DNS.free_request_id(service[0], service[1], id) + } + end + + class Sender < Requester::Sender # :nodoc: + def initialize(msg, data, sock, host, port) + super(msg, data, sock) + @host = host + @port = port + end + attr_reader :data + + def send + @sock.send(@msg, 0, @host, @port) + end + end + end + + class ConnectedUDP < Requester # :nodoc: + def initialize(host, port=Port) + super() + @host = host + @port = port + @sock = UDPSocket.new(host.index(':') ? Socket::AF_INET6 : Socket::AF_INET) + DNS.bind_random_port(@sock) + @sock.connect(host, port) + @sock.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC) if defined? Fcntl::F_SETFD + end + + def recv_reply + reply = @sock.recv(UDPSize) + return reply, nil + end + + def sender(msg, data, host=@host, port=@port) + unless host == @host && port == @port + raise RequestError.new("host/port don't match: #{host}:#{port}") + end + id = DNS.allocate_request_id(@host, @port) + request = msg.encode + request[0,2] = [id].pack('n') + return @senders[[nil,id]] = Sender.new(request, data, @sock) + end + + def close + super + @senders.each_key {|from, id| + DNS.free_request_id(@host, @port, id) + } + end + + class Sender < Requester::Sender # :nodoc: + def send + @sock.send(@msg, 0) + end + attr_reader :data + end + end + + class TCP < Requester # :nodoc: + def initialize(host, port=Port) + super() + @host = host + @port = port + @sock = TCPSocket.new(@host, @port) + @sock.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC) if defined? Fcntl::F_SETFD + @senders = {} + end + + def recv_reply + len = @sock.read(2).unpack('n')[0] + reply = @sock.read(len) + return reply, nil + end + + def sender(msg, data, host=@host, port=@port) + unless host == @host && port == @port + raise RequestError.new("host/port don't match: #{host}:#{port}") + end + id = DNS.allocate_request_id(@host, @port) + request = msg.encode + request[0,2] = [request.length, id].pack('nn') + return @senders[[nil,id]] = Sender.new(request, data, @sock) + end + + class Sender < Requester::Sender # :nodoc: + def send + @sock.print(@msg) + @sock.flush + end + attr_reader :data + end + + def close + super + @senders.each_key {|from,id| + DNS.free_request_id(@host, @port, id) + } + end + end + + ## + # Indicates a problem with the DNS request. + + class RequestError < StandardError + end + end + + class Config # :nodoc: + def initialize(config_info=nil) + @mutex = Mutex.new + @config_info = config_info + @initialized = nil + end + + def Config.parse_resolv_conf(filename) + nameserver = [] + search = nil + ndots = 1 + open(filename) {|f| + f.each {|line| + line.sub!(/[#;].*/, '') + keyword, *args = line.split(/\s+/) + args.each { |arg| + arg.untaint + } + next unless keyword + case keyword + when 'nameserver' + nameserver += args + when 'domain' + next if args.empty? + search = [args[0]] + when 'search' + next if args.empty? + search = args + when 'options' + args.each {|arg| + case arg + when /\Andots:(\d+)\z/ + ndots = $1.to_i + end + } + end + } + } + return { :nameserver => nameserver, :search => search, :ndots => ndots } + end + + def Config.default_config_hash(filename="/etc/resolv.conf") + if File.exist? filename + config_hash = Config.parse_resolv_conf(filename) + else + if /mswin32|cygwin|mingw|bccwin/ =~ RUBY_PLATFORM + require 'win32/resolv' + search, nameserver = Win32::Resolv.get_resolv_info + config_hash = {} + config_hash[:nameserver] = nameserver if nameserver + config_hash[:search] = [search].flatten if search + end + end + config_hash + end + + def lazy_initialize + @mutex.synchronize { + unless @initialized + @nameserver = [] + @search = nil + @ndots = 1 + case @config_info + when nil + config_hash = Config.default_config_hash + when String + config_hash = Config.parse_resolv_conf(@config_info) + when Hash + config_hash = @config_info.dup + if String === config_hash[:nameserver] + config_hash[:nameserver] = [config_hash[:nameserver]] + end + if String === config_hash[:search] + config_hash[:search] = [config_hash[:search]] + end + else + raise ArgumentError.new("invalid resolv configuration: #{@config_info.inspect}") + end + @nameserver = config_hash[:nameserver] if config_hash.include? :nameserver + @search = config_hash[:search] if config_hash.include? :search + @ndots = config_hash[:ndots] if config_hash.include? :ndots + + @nameserver = ['0.0.0.0'] if @nameserver.empty? + if @search + @search = @search.map {|arg| Label.split(arg) } + else + hostname = Socket.gethostname + if /\./ =~ hostname + @search = [Label.split($')] + else + @search = [[]] + end + end + + if !@nameserver.kind_of?(Array) || + !@nameserver.all? {|ns| String === ns } + raise ArgumentError.new("invalid nameserver config: #{@nameserver.inspect}") + end + + if !@search.kind_of?(Array) || + !@search.all? {|ls| ls.all? {|l| Label::Str === l } } + raise ArgumentError.new("invalid search config: #{@search.inspect}") + end + + if !@ndots.kind_of?(Integer) + raise ArgumentError.new("invalid ndots config: #{@ndots.inspect}") + end + + @initialized = true + end + } + self + end + + def single? + lazy_initialize + if @nameserver.length == 1 + return @nameserver[0] + else + return nil + end + end + + def generate_candidates(name) + candidates = nil + name = Name.create(name) + if name.absolute? + candidates = [name] + else + if @ndots <= name.length - 1 + candidates = [Name.new(name.to_a)] + else + candidates = [] + end + candidates.concat(@search.map {|domain| Name.new(name.to_a + domain)}) + end + return candidates + end + + InitialTimeout = 5 + + def generate_timeouts + ts = [InitialTimeout] + ts << ts[-1] * 2 / @nameserver.length + ts << ts[-1] * 2 + ts << ts[-1] * 2 + return ts + end + + def resolv(name) + candidates = generate_candidates(name) + timeouts = generate_timeouts + begin + candidates.each {|candidate| + begin + timeouts.each {|tout| + @nameserver.each {|nameserver| + begin + yield candidate, tout, nameserver + rescue ResolvTimeout + end + } + } + raise ResolvError.new("DNS resolv timeout: #{name}") + rescue NXDomain + end + } + rescue ResolvError + end + end + + ## + # Indicates no such domain was found. + + class NXDomain < ResolvError + end + + ## + # Indicates some other unhandled resolver error was encountered. + + class OtherResolvError < ResolvError + end + end + + module OpCode # :nodoc: + Query = 0 + IQuery = 1 + Status = 2 + Notify = 4 + Update = 5 + end + + module RCode # :nodoc: + NoError = 0 + FormErr = 1 + ServFail = 2 + NXDomain = 3 + NotImp = 4 + Refused = 5 + YXDomain = 6 + YXRRSet = 7 + NXRRSet = 8 + NotAuth = 9 + NotZone = 10 + BADVERS = 16 + BADSIG = 16 + BADKEY = 17 + BADTIME = 18 + BADMODE = 19 + BADNAME = 20 + BADALG = 21 + end + + ## + # Indicates that the DNS response was unable to be decoded. + + class DecodeError < StandardError + end + + ## + # Indicates that the DNS request was unable to be encoded. + + class EncodeError < StandardError + end + + module Label # :nodoc: + def self.split(arg) + labels = [] + arg.scan(/[^\.]+/) {labels << Str.new($&)} + return labels + end + + class Str # :nodoc: + def initialize(string) + @string = string + @downcase = string.downcase + end + attr_reader :string, :downcase + + def to_s + return @string + end + + def inspect + return "#<#{self.class} #{self.to_s}>" + end + + def ==(other) + return @downcase == other.downcase + end + + def eql?(other) + return self == other + end + + def hash + return @downcase.hash + end + end + end + + ## + # A representation of a DNS name. + + class Name + + ## + # Creates a new DNS name from +arg+. +arg+ can be: + # + # Name:: returns +arg+. + # String:: Creates a new Name. + + def self.create(arg) + case arg + when Name + return arg + when String + return Name.new(Label.split(arg), /\.\z/ =~ arg ? true : false) + else + raise ArgumentError.new("cannot interpret as DNS name: #{arg.inspect}") + end + end + + def initialize(labels, absolute=true) # :nodoc: + @labels = labels + @absolute = absolute + end + + def inspect # :nodoc: + "#<#{self.class}: #{self.to_s}#{@absolute ? '.' : ''}>" + end + + ## + # True if this name is absolute. + + def absolute? + return @absolute + end + + def ==(other) # :nodoc: + return false unless Name === other + return @labels.join == other.to_a.join && @absolute == other.absolute? + end + + alias eql? == # :nodoc: + + ## + # Returns true if +other+ is a subdomain. + # + # Example: + # + # domain = Resolv::DNS::Name.create("y.z") + # p Resolv::DNS::Name.create("w.x.y.z").subdomain_of?(domain) #=> true + # p Resolv::DNS::Name.create("x.y.z").subdomain_of?(domain) #=> true + # p Resolv::DNS::Name.create("y.z").subdomain_of?(domain) #=> false + # p Resolv::DNS::Name.create("z").subdomain_of?(domain) #=> false + # p Resolv::DNS::Name.create("x.y.z.").subdomain_of?(domain) #=> false + # p Resolv::DNS::Name.create("w.z").subdomain_of?(domain) #=> false + # + + def subdomain_of?(other) + raise ArgumentError, "not a domain name: #{other.inspect}" unless Name === other + return false if @absolute != other.absolute? + other_len = other.length + return false if @labels.length <= other_len + return @labels[-other_len, other_len] == other.to_a + end + + def hash # :nodoc: + return @labels.hash ^ @absolute.hash + end + + def to_a # :nodoc: + return @labels + end + + def length # :nodoc: + return @labels.length + end + + def [](i) # :nodoc: + return @labels[i] + end + + ## + # returns the domain name as a string. + # + # The domain name doesn't have a trailing dot even if the name object is + # absolute. + # + # Example: + # + # p Resolv::DNS::Name.create("x.y.z.").to_s #=> "x.y.z" + # p Resolv::DNS::Name.create("x.y.z").to_s #=> "x.y.z" + + def to_s + return @labels.join('.') + end + end + + class Message # :nodoc: + @@identifier = -1 + + def initialize(id = (@@identifier += 1) & 0xffff) + @id = id + @qr = 0 + @opcode = 0 + @aa = 0 + @tc = 0 + @rd = 0 # recursion desired + @ra = 0 # recursion available + @rcode = 0 + @question = [] + @answer = [] + @authority = [] + @additional = [] + end + + attr_accessor :id, :qr, :opcode, :aa, :tc, :rd, :ra, :rcode + attr_reader :question, :answer, :authority, :additional + + def ==(other) + return @id == other.id && + @qr == other.qr && + @opcode == other.opcode && + @aa == other.aa && + @tc == other.tc && + @rd == other.rd && + @ra == other.ra && + @rcode == other.rcode && + @question == other.question && + @answer == other.answer && + @authority == other.authority && + @additional == other.additional + end + + def add_question(name, typeclass) + @question << [Name.create(name), typeclass] + end + + def each_question + @question.each {|name, typeclass| + yield name, typeclass + } + end + + def add_answer(name, ttl, data) + @answer << [Name.create(name), ttl, data] + end + + def each_answer + @answer.each {|name, ttl, data| + yield name, ttl, data + } + end + + def add_authority(name, ttl, data) + @authority << [Name.create(name), ttl, data] + end + + def each_authority + @authority.each {|name, ttl, data| + yield name, ttl, data + } + end + + def add_additional(name, ttl, data) + @additional << [Name.create(name), ttl, data] + end + + def each_additional + @additional.each {|name, ttl, data| + yield name, ttl, data + } + end + + def each_resource + each_answer {|name, ttl, data| yield name, ttl, data} + each_authority {|name, ttl, data| yield name, ttl, data} + each_additional {|name, ttl, data| yield name, ttl, data} + end + + def encode + return MessageEncoder.new {|msg| + msg.put_pack('nnnnnn', + @id, + (@qr & 1) << 15 | + (@opcode & 15) << 11 | + (@aa & 1) << 10 | + (@tc & 1) << 9 | + (@rd & 1) << 8 | + (@ra & 1) << 7 | + (@rcode & 15), + @question.length, + @answer.length, + @authority.length, + @additional.length) + @question.each {|q| + name, typeclass = q + msg.put_name(name) + msg.put_pack('nn', typeclass::TypeValue, typeclass::ClassValue) + } + [@answer, @authority, @additional].each {|rr| + rr.each {|r| + name, ttl, data = r + msg.put_name(name) + msg.put_pack('nnN', data.class::TypeValue, data.class::ClassValue, ttl) + msg.put_length16 {data.encode_rdata(msg)} + } + } + }.to_s + end + + class MessageEncoder # :nodoc: + def initialize + @data = '' + @names = {} + yield self + end + + def to_s + return @data + end + + def put_bytes(d) + @data << d + end + + def put_pack(template, *d) + @data << d.pack(template) + end + + def put_length16 + length_index = @data.length + @data << "\0\0" + data_start = @data.length + yield + data_end = @data.length + @data[length_index, 2] = [data_end - data_start].pack("n") + end + + def put_string(d) + self.put_pack("C", d.length) + @data << d + end + + def put_string_list(ds) + ds.each {|d| + self.put_string(d) + } + end + + def put_name(d) + put_labels(d.to_a) + end + + def put_labels(d) + d.each_index {|i| + domain = d[i..-1] + if idx = @names[domain] + self.put_pack("n", 0xc000 | idx) + return + else + @names[domain] = @data.length + self.put_label(d[i]) + end + } + @data << "\0" + end + + def put_label(d) + self.put_string(d.to_s) + end + end + + def Message.decode(m) + o = Message.new(0) + MessageDecoder.new(m) {|msg| + id, flag, qdcount, ancount, nscount, arcount = + msg.get_unpack('nnnnnn') + o.id = id + o.qr = (flag >> 15) & 1 + o.opcode = (flag >> 11) & 15 + o.aa = (flag >> 10) & 1 + o.tc = (flag >> 9) & 1 + o.rd = (flag >> 8) & 1 + o.ra = (flag >> 7) & 1 + o.rcode = flag & 15 + (1..qdcount).each { + name, typeclass = msg.get_question + o.add_question(name, typeclass) + } + (1..ancount).each { + name, ttl, data = msg.get_rr + o.add_answer(name, ttl, data) + } + (1..nscount).each { + name, ttl, data = msg.get_rr + o.add_authority(name, ttl, data) + } + (1..arcount).each { + name, ttl, data = msg.get_rr + o.add_additional(name, ttl, data) + } + } + return o + end + + class MessageDecoder # :nodoc: + def initialize(data) + @data = data + @index = 0 + @limit = data.length + yield self + end + + def get_length16 + len, = self.get_unpack('n') + save_limit = @limit + @limit = @index + len + d = yield(len) + if @index < @limit + raise DecodeError.new("junk exists") + elsif @limit < @index + raise DecodeError.new("limit exceeded") + end + @limit = save_limit + return d + end + + def get_bytes(len = @limit - @index) + d = @data[@index, len] + @index += len + return d + end + + def get_unpack(template) + len = 0 + template.each_byte {|byte| + byte = "%c" % byte + case byte + when ?c, ?C + len += 1 + when ?n + len += 2 + when ?N + len += 4 + else + raise StandardError.new("unsupported template: '#{byte.chr}' in '#{template}'") + end + } + raise DecodeError.new("limit exceeded") if @limit < @index + len + arr = @data.unpack("@#{@index}#{template}") + @index += len + return arr + end + + def get_string + len = @data[@index].ord + raise DecodeError.new("limit exceeded") if @limit < @index + 1 + len + d = @data[@index + 1, len] + @index += 1 + len + return d + end + + def get_string_list + strings = [] + while @index < @limit + strings << self.get_string + end + strings + end + + def get_name + return Name.new(self.get_labels) + end + + def get_labels(limit=nil) + limit = @index if !limit || @index < limit + d = [] + while true + case @data[@index].ord + when 0 + @index += 1 + return d + when 192..255 + idx = self.get_unpack('n')[0] & 0x3fff + if limit <= idx + raise DecodeError.new("non-backward name pointer") + end + save_index = @index + @index = idx + d += self.get_labels(limit) + @index = save_index + return d + else + d << self.get_label + end + end + return d + end + + def get_label + return Label::Str.new(self.get_string) + end + + def get_question + name = self.get_name + type, klass = self.get_unpack("nn") + return name, Resource.get_class(type, klass) + end + + def get_rr + name = self.get_name + type, klass, ttl = self.get_unpack('nnN') + typeclass = Resource.get_class(type, klass) + res = self.get_length16 { typeclass.decode_rdata self } + res.instance_variable_set :@ttl, ttl + return name, ttl, res + end + end + end + + ## + # A DNS query abstract class. + + class Query + def encode_rdata(msg) # :nodoc: + raise EncodeError.new("#{self.class} is query.") + end + + def self.decode_rdata(msg) # :nodoc: + raise DecodeError.new("#{self.class} is query.") + end + end + + ## + # A DNS resource abstract class. + + class Resource < Query + + ## + # Remaining Time To Live for this Resource. + + attr_reader :ttl + + ClassHash = {} # :nodoc: + + def encode_rdata(msg) # :nodoc: + raise NotImplementedError.new + end + + def self.decode_rdata(msg) # :nodoc: + raise NotImplementedError.new + end + + def ==(other) # :nodoc: + return false unless self.class == other.class + s_ivars = self.instance_variables + s_ivars.sort! + s_ivars.delete "@ttl" + o_ivars = other.instance_variables + o_ivars.sort! + o_ivars.delete "@ttl" + return s_ivars == o_ivars && + s_ivars.collect {|name| self.instance_variable_get name} == + o_ivars.collect {|name| other.instance_variable_get name} + end + + def eql?(other) # :nodoc: + return self == other + end + + def hash # :nodoc: + h = 0 + vars = self.instance_variables + vars.delete "@ttl" + vars.each {|name| + h ^= self.instance_variable_get(name).hash + } + return h + end + + def self.get_class(type_value, class_value) # :nodoc: + return ClassHash[[type_value, class_value]] || + Generic.create(type_value, class_value) + end + + ## + # A generic resource abstract class. + + class Generic < Resource + + ## + # Creates a new generic resource. + + def initialize(data) + @data = data + end + + ## + # Data for this generic resource. + + attr_reader :data + + def encode_rdata(msg) # :nodoc: + msg.put_bytes(data) + end + + def self.decode_rdata(msg) # :nodoc: + return self.new(msg.get_bytes) + end + + def self.create(type_value, class_value) # :nodoc: + c = Class.new(Generic) + c.const_set(:TypeValue, type_value) + c.const_set(:ClassValue, class_value) + Generic.const_set("Type#{type_value}_Class#{class_value}", c) + ClassHash[[type_value, class_value]] = c + return c + end + end + + ## + # Domain Name resource abstract class. + + class DomainName < Resource + + ## + # Creates a new DomainName from +name+. + + def initialize(name) + @name = name + end + + ## + # The name of this DomainName. + + attr_reader :name + + def encode_rdata(msg) # :nodoc: + msg.put_name(@name) + end + + def self.decode_rdata(msg) # :nodoc: + return self.new(msg.get_name) + end + end + + # Standard (class generic) RRs + + ClassValue = nil # :nodoc: + + ## + # An authoritative name server. + + class NS < DomainName + TypeValue = 2 # :nodoc: + end + + ## + # The canonical name for an alias. + + class CNAME < DomainName + TypeValue = 5 # :nodoc: + end + + ## + # Start Of Authority resource. + + class SOA < Resource + + TypeValue = 6 # :nodoc: + + ## + # Creates a new SOA record. See the attr documentation for the + # details of each argument. + + def initialize(mname, rname, serial, refresh, retry_, expire, minimum) + @mname = mname + @rname = rname + @serial = serial + @refresh = refresh + @retry = retry_ + @expire = expire + @minimum = minimum + end + + ## + # Name of the host where the master zone file for this zone resides. + + attr_reader :mname + + ## + # The person responsible for this domain name. + + attr_reader :rname + + ## + # The version number of the zone file. + + attr_reader :serial + + ## + # How often, in seconds, a secondary name server is to check for + # updates from the primary name server. + + attr_reader :refresh + + ## + # How often, in seconds, a secondary name server is to retry after a + # failure to check for a refresh. + + attr_reader :retry + + ## + # Time in seconds that a secondary name server is to use the data + # before refreshing from the primary name server. + + attr_reader :expire + + ## + # The minimum number of seconds to be used for TTL values in RRs. + + attr_reader :minimum + + def encode_rdata(msg) # :nodoc: + msg.put_name(@mname) + msg.put_name(@rname) + msg.put_pack('NNNNN', @serial, @refresh, @retry, @expire, @minimum) + end + + def self.decode_rdata(msg) # :nodoc: + mname = msg.get_name + rname = msg.get_name + serial, refresh, retry_, expire, minimum = msg.get_unpack('NNNNN') + return self.new( + mname, rname, serial, refresh, retry_, expire, minimum) + end + end + + ## + # A Pointer to another DNS name. + + class PTR < DomainName + TypeValue = 12 # :nodoc: + end + + ## + # Host Information resource. + + class HINFO < Resource + + TypeValue = 13 # :nodoc: + + ## + # Creates a new HINFO running +os+ on +cpu+. + + def initialize(cpu, os) + @cpu = cpu + @os = os + end + + ## + # CPU architecture for this resource. + + attr_reader :cpu + + ## + # Operating system for this resource. + + attr_reader :os + + def encode_rdata(msg) # :nodoc: + msg.put_string(@cpu) + msg.put_string(@os) + end + + def self.decode_rdata(msg) # :nodoc: + cpu = msg.get_string + os = msg.get_string + return self.new(cpu, os) + end + end + + ## + # Mailing list or mailbox information. + + class MINFO < Resource + + TypeValue = 14 # :nodoc: + + def initialize(rmailbx, emailbx) + @rmailbx = rmailbx + @emailbx = emailbx + end + + ## + # Domain name responsible for this mail list or mailbox. + + attr_reader :rmailbx + + ## + # Mailbox to use for error messages related to the mail list or mailbox. + + attr_reader :emailbx + + def encode_rdata(msg) # :nodoc: + msg.put_name(@rmailbx) + msg.put_name(@emailbx) + end + + def self.decode_rdata(msg) # :nodoc: + rmailbx = msg.get_string + emailbx = msg.get_string + return self.new(rmailbx, emailbx) + end + end + + ## + # Mail Exchanger resource. + + class MX < Resource + + TypeValue= 15 # :nodoc: + + ## + # Creates a new MX record with +preference+, accepting mail at + # +exchange+. + + def initialize(preference, exchange) + @preference = preference + @exchange = exchange + end + + ## + # The preference for this MX. + + attr_reader :preference + + ## + # The host of this MX. + + attr_reader :exchange + + def encode_rdata(msg) # :nodoc: + msg.put_pack('n', @preference) + msg.put_name(@exchange) + end + + def self.decode_rdata(msg) # :nodoc: + preference, = msg.get_unpack('n') + exchange = msg.get_name + return self.new(preference, exchange) + end + end + + ## + # Unstructured text resource. + + class TXT < Resource + + TypeValue = 16 # :nodoc: + + def initialize(first_string, *rest_strings) + @strings = [first_string, *rest_strings] + end + + ## + # Returns an Array of Strings for this TXT record. + + attr_reader :strings + + ## + # Returns the first string from +strings+. + + def data + @strings[0] + end + + def encode_rdata(msg) # :nodoc: + msg.put_string_list(@strings) + end + + def self.decode_rdata(msg) # :nodoc: + strings = msg.get_string_list + return self.new(*strings) + end + end + + ## + # A Query type requesting any RR. + + class ANY < Query + TypeValue = 255 # :nodoc: + end + + ClassInsensitiveTypes = [ # :nodoc: + NS, CNAME, SOA, PTR, HINFO, MINFO, MX, TXT, ANY + ] + + ## + # module IN contains ARPA Internet specific RRs. + + module IN + + ClassValue = 1 # :nodoc: + + ClassInsensitiveTypes.each {|s| + c = Class.new(s) + c.const_set(:TypeValue, s::TypeValue) + c.const_set(:ClassValue, ClassValue) + ClassHash[[s::TypeValue, ClassValue]] = c + self.const_set(s.name.sub(/.*::/, ''), c) + } + + ## + # IPv4 Address resource + + class A < Resource + TypeValue = 1 + ClassValue = IN::ClassValue + ClassHash[[TypeValue, ClassValue]] = self # :nodoc: + + ## + # Creates a new A for +address+. + + def initialize(address) + @address = IPv4.create(address) + end + + ## + # The Resolv::IPv4 address for this A. + + attr_reader :address + + def encode_rdata(msg) # :nodoc: + msg.put_bytes(@address.address) + end + + def self.decode_rdata(msg) # :nodoc: + return self.new(IPv4.new(msg.get_bytes(4))) + end + end + + ## + # Well Known Service resource. + + class WKS < Resource + TypeValue = 11 + ClassValue = IN::ClassValue + ClassHash[[TypeValue, ClassValue]] = self # :nodoc: + + def initialize(address, protocol, bitmap) + @address = IPv4.create(address) + @protocol = protocol + @bitmap = bitmap + end + + ## + # The host these services run on. + + attr_reader :address + + ## + # IP protocol number for these services. + + attr_reader :protocol + + ## + # A bit map of enabled services on this host. + # + # If protocol is 6 (TCP) then the 26th bit corresponds to the SMTP + # service (port 25). If this bit is set, then an SMTP server should + # be listening on TCP port 25; if zero, SMTP service is not + # supported. + + attr_reader :bitmap + + def encode_rdata(msg) # :nodoc: + msg.put_bytes(@address.address) + msg.put_pack("n", @protocol) + msg.put_bytes(@bitmap) + end + + def self.decode_rdata(msg) # :nodoc: + address = IPv4.new(msg.get_bytes(4)) + protocol, = msg.get_unpack("n") + bitmap = msg.get_bytes + return self.new(address, protocol, bitmap) + end + end + + ## + # An IPv6 address record. + + class AAAA < Resource + TypeValue = 28 + ClassValue = IN::ClassValue + ClassHash[[TypeValue, ClassValue]] = self # :nodoc: + + ## + # Creates a new AAAA for +address+. + + def initialize(address) + @address = IPv6.create(address) + end + + ## + # The Resolv::IPv6 address for this AAAA. + + attr_reader :address + + def encode_rdata(msg) # :nodoc: + msg.put_bytes(@address.address) + end + + def self.decode_rdata(msg) # :nodoc: + return self.new(IPv6.new(msg.get_bytes(16))) + end + end + + ## + # SRV resource record defined in RFC 2782 + # + # These records identify the hostname and port that a service is + # available at. + + class SRV < Resource + TypeValue = 33 + ClassValue = IN::ClassValue + ClassHash[[TypeValue, ClassValue]] = self # :nodoc: + + # Create a SRV resource record. + # + # See the documentation for #priority, #weight, #port and #target + # for +priority+, +weight+, +port and +target+ respectively. + + def initialize(priority, weight, port, target) + @priority = priority.to_int + @weight = weight.to_int + @port = port.to_int + @target = Name.create(target) + end + + # The priority of this target host. + # + # A client MUST attempt to contact the target host with the + # lowest-numbered priority it can reach; target hosts with the same + # priority SHOULD be tried in an order defined by the weight field. + # The range is 0-65535. Note that it is not widely implemented and + # should be set to zero. + + attr_reader :priority + + # A server selection mechanism. + # + # The weight field specifies a relative weight for entries with the + # same priority. Larger weights SHOULD be given a proportionately + # higher probability of being selected. The range of this number is + # 0-65535. Domain administrators SHOULD use Weight 0 when there + # isn't any server selection to do, to make the RR easier to read + # for humans (less noisy). Note that it is not widely implemented + # and should be set to zero. + + attr_reader :weight + + # The port on this target host of this service. + # + # The range is 0-65535. + + attr_reader :port + + # The domain name of the target host. + # + # A target of "." means that the service is decidedly not available + # at this domain. + + attr_reader :target + + def encode_rdata(msg) # :nodoc: + msg.put_pack("n", @priority) + msg.put_pack("n", @weight) + msg.put_pack("n", @port) + msg.put_name(@target) + end + + def self.decode_rdata(msg) # :nodoc: + priority, = msg.get_unpack("n") + weight, = msg.get_unpack("n") + port, = msg.get_unpack("n") + target = msg.get_name + return self.new(priority, weight, port, target) + end + end + end + end + end + + ## + # A Resolv::DNS IPv4 address. + + class IPv4 + + ## + # Regular expression IPv4 addresses must match. + + Regex = /\A(\d+)\.(\d+)\.(\d+)\.(\d+)\z/ + + def self.create(arg) + case arg + when IPv4 + return arg + when Regex + if (0..255) === (a = $1.to_i) && + (0..255) === (b = $2.to_i) && + (0..255) === (c = $3.to_i) && + (0..255) === (d = $4.to_i) + return self.new([a, b, c, d].pack("CCCC")) + else + raise ArgumentError.new("IPv4 address with invalid value: " + arg) + end + else + raise ArgumentError.new("cannot interpret as IPv4 address: #{arg.inspect}") + end + end + + def initialize(address) # :nodoc: + unless address.kind_of?(String) && address.length == 4 + raise ArgumentError.new('IPv4 address must be 4 bytes') + end + @address = address + end + + ## + # A String representation of this IPv4 address. + + ## + # The raw IPv4 address as a String. + + attr_reader :address + + def to_s # :nodoc: + return sprintf("%d.%d.%d.%d", *@address.unpack("CCCC")) + end + + def inspect # :nodoc: + return "#<#{self.class} #{self.to_s}>" + end + + ## + # Turns this IPv4 address into a Resolv::DNS::Name. + + def to_name + return DNS::Name.create( + '%d.%d.%d.%d.in-addr.arpa.' % @address.unpack('CCCC').reverse) + end + + def ==(other) # :nodoc: + return @address == other.address + end + + def eql?(other) # :nodoc: + return self == other + end + + def hash # :nodoc: + return @address.hash + end + end + + ## + # A Resolv::DNS IPv6 address. + + class IPv6 + + ## + # IPv6 address format a:b:c:d:e:f:g:h + Regex_8Hex = /\A + (?:[0-9A-Fa-f]{1,4}:){7} + [0-9A-Fa-f]{1,4} + \z/x + + ## + # Compressed IPv6 address format a::b + + Regex_CompressedHex = /\A + ((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?) :: + ((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?) + \z/x + + ## + # IPv4 mapped IPv6 address format a:b:c:d:e:f:w.x.y.z + + Regex_6Hex4Dec = /\A + ((?:[0-9A-Fa-f]{1,4}:){6,6}) + (\d+)\.(\d+)\.(\d+)\.(\d+) + \z/x + + ## + # Compressed IPv4 mapped IPv6 address format a::b:w.x.y.z + + Regex_CompressedHex4Dec = /\A + ((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?) :: + ((?:[0-9A-Fa-f]{1,4}:)*) + (\d+)\.(\d+)\.(\d+)\.(\d+) + \z/x + + ## + # A composite IPv6 address Regexp. + + Regex = / + (?:#{Regex_8Hex}) | + (?:#{Regex_CompressedHex}) | + (?:#{Regex_6Hex4Dec}) | + (?:#{Regex_CompressedHex4Dec})/x + + ## + # Creates a new IPv6 address from +arg+ which may be: + # + # IPv6:: returns +arg+. + # String:: +arg+ must match one of the IPv6::Regex* constants + + def self.create(arg) + case arg + when IPv6 + return arg + when String + address = '' + if Regex_8Hex =~ arg + arg.scan(/[0-9A-Fa-f]+/) {|hex| address << [hex.hex].pack('n')} + elsif Regex_CompressedHex =~ arg + prefix = $1 + suffix = $2 + a1 = '' + a2 = '' + prefix.scan(/[0-9A-Fa-f]+/) {|hex| a1 << [hex.hex].pack('n')} + suffix.scan(/[0-9A-Fa-f]+/) {|hex| a2 << [hex.hex].pack('n')} + omitlen = 16 - a1.length - a2.length + address << a1 << "\0" * omitlen << a2 + elsif Regex_6Hex4Dec =~ arg + prefix, a, b, c, d = $1, $2.to_i, $3.to_i, $4.to_i, $5.to_i + if (0..255) === a && (0..255) === b && (0..255) === c && (0..255) === d + prefix.scan(/[0-9A-Fa-f]+/) {|hex| address << [hex.hex].pack('n')} + address << [a, b, c, d].pack('CCCC') + else + raise ArgumentError.new("not numeric IPv6 address: " + arg) + end + elsif Regex_CompressedHex4Dec =~ arg + prefix, suffix, a, b, c, d = $1, $2, $3.to_i, $4.to_i, $5.to_i, $6.to_i + if (0..255) === a && (0..255) === b && (0..255) === c && (0..255) === d + a1 = '' + a2 = '' + prefix.scan(/[0-9A-Fa-f]+/) {|hex| a1 << [hex.hex].pack('n')} + suffix.scan(/[0-9A-Fa-f]+/) {|hex| a2 << [hex.hex].pack('n')} + omitlen = 12 - a1.length - a2.length + address << a1 << "\0" * omitlen << a2 << [a, b, c, d].pack('CCCC') + else + raise ArgumentError.new("not numeric IPv6 address: " + arg) + end + else + raise ArgumentError.new("not numeric IPv6 address: " + arg) + end + return IPv6.new(address) + else + raise ArgumentError.new("cannot interpret as IPv6 address: #{arg.inspect}") + end + end + + def initialize(address) # :nodoc: + unless address.kind_of?(String) && address.length == 16 + raise ArgumentError.new('IPv6 address must be 16 bytes') + end + @address = address + end + + ## + # The raw IPv6 address as a String. + + attr_reader :address + + def to_s # :nodoc: + address = sprintf("%X:%X:%X:%X:%X:%X:%X:%X", *@address.unpack("nnnnnnnn")) + unless address.sub!(/(^|:)0(:0)+(:|$)/, '::') + address.sub!(/(^|:)0(:|$)/, '::') + end + return address + end + + def inspect # :nodoc: + return "#<#{self.class} #{self.to_s}>" + end + + ## + # Turns this IPv6 address into a Resolv::DNS::Name. + #-- + # ip6.arpa should be searched too. [RFC3152] + + def to_name + return DNS::Name.new( + @address.unpack("H32")[0].split(//).reverse + ['ip6', 'arpa']) + end + + def ==(other) # :nodoc: + return @address == other.address + end + + def eql?(other) # :nodoc: + return self == other + end + + def hash # :nodoc: + return @address.hash + end + end + + ## + # Default resolver to use for Resolv class methods. + + DefaultResolver = self.new + + ## + # Address Regexp to use for matching IP addresses. + + AddressRegex = /(?:#{IPv4::Regex})|(?:#{IPv6::Regex})/ + +end + |