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Added resolv.rb, resolv-replace.rb from 1.9.2p290.

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commit 918ed1c54254d1698c300eb555668803341302b0 1 parent c516b71
@brixen brixen authored
Showing with 2,415 additions and 0 deletions.
  1. +75 −0 lib/19/resolv-replace.rb
  2. +2,340 −0 lib/19/resolv.rb
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75 lib/19/resolv-replace.rb
@@ -0,0 +1,75 @@
+require 'socket'
+require 'resolv'
+
+class << IPSocket
+ # :stopdoc:
+ alias original_resolv_getaddress getaddress
+ # :startdoc:
+ def getaddress(host)
+ begin
+ return Resolv.getaddress(host).to_s
+ rescue Resolv::ResolvError
+ raise SocketError, "Hostname not known: #{host}"
+ end
+ end
+end
+
+class TCPSocket < IPSocket
+ # :stopdoc:
+ alias original_resolv_initialize initialize
+ # :startdoc:
+ def initialize(host, serv, *rest)
+ rest[0] = IPSocket.getaddress(rest[0]) unless rest.empty?
+ original_resolv_initialize(IPSocket.getaddress(host), serv, *rest)
+ end
+end
+
+class UDPSocket < IPSocket
+ # :stopdoc:
+ alias original_resolv_bind bind
+ # :startdoc:
+ def bind(host, port)
+ host = IPSocket.getaddress(host) if host != ""
+ original_resolv_bind(host, port)
+ end
+
+ # :stopdoc:
+ alias original_resolv_connect connect
+ # :startdoc:
+ def connect(host, port)
+ original_resolv_connect(IPSocket.getaddress(host), port)
+ end
+
+ # :stopdoc:
+ alias original_resolv_send send
+ # :startdoc:
+ def send(mesg, flags, *rest)
+ if rest.length == 2
+ host, port = rest
+ begin
+ addrs = Resolv.getaddresses(host)
+ rescue Resolv::ResolvError
+ raise SocketError, "Hostname not known: #{host}"
+ end
+ err = nil
+ addrs[0...-1].each {|addr|
+ begin
+ return original_resolv_send(mesg, flags, addr, port)
+ rescue SystemCallError
+ end
+ }
+ original_resolv_send(mesg, flags, addrs[-1], port)
+ else
+ original_resolv_send(mesg, flags, *rest)
+ end
+ end
+end
+
+class SOCKSSocket < TCPSocket
+ # :stopdoc:
+ alias original_resolv_initialize initialize
+ # :startdoc:
+ def initialize(host, serv)
+ original_resolv_initialize(IPSocket.getaddress(host), port)
+ end
+end if defined? SOCKSSocket
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2,340 lib/19/resolv.rb
@@ -0,0 +1,2340 @@
+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 entire 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
+
+ ##
+ # Resolv::Hosts is a hostname resolver that uses the system hosts file.
+
+ class Hosts
+ if /mswin|mingw|bccwin/ =~ RUBY_PLATFORM
+ require 'win32/resolv'
+ DefaultFileName = Win32::Resolv.get_hosts_path
+ else
+ DefaultFileName = '/etc/hosts'
+ end
+
+ ##
+ # Creates a new Resolv::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.
+ # :nameserver_port can be used to specify port number of nameserver address.
+ #
+ # The value of :nameserver should be an address string or
+ # an array of address strings.
+ # - :nameserver => '8.8.8.8'
+ # - :nameserver => ['8.8.8.8', '8.8.4.4']
+ #
+ # The value of :nameserver_port should be an array of
+ # pair of nameserver address and port number.
+ # - :nameserver_port => [['8.8.8.8', 53], ['8.8.4.4', 53]]
+ #
+ # 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}
+ if use_ipv6?
+ each_resource(name, Resource::IN::AAAA) {|resource| yield resource.address}
+ end
+ end
+
+ def use_ipv6?
+ begin
+ list = Socket.ip_address_list
+ rescue NotImplementedError
+ return true
+ end
+ list.any? {|a| a.ipv6? && !a.ipv6_loopback? && !a.ipv6_linklocal? }
+ end
+ private :use_ipv6?
+
+ ##
+ # 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, port|
+ msg = Message.new
+ msg.rd = 1
+ msg.add_question(candidate, typeclass)
+ unless sender = senders[[candidate, nameserver, port]]
+ sender = senders[[candidate, nameserver, port]] =
+ requester.sender(msg, candidate, nameserver, port)
+ 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:
+ nameserver_port = @config.nameserver_port
+ if nameserver_port.length == 1
+ Requester::ConnectedUDP.new(*nameserver_port[0])
+ else
+ Requester::UnconnectedUDP.new(*nameserver_port)
+ 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, bind_host="0.0.0.0") # :nodoc:
+ begin
+ port = rangerand(1024..65535)
+ udpsock.bind(bind_host, port)
+ rescue Errno::EADDRINUSE
+ retry
+ end
+ end
+
+ class Requester # :nodoc:
+ def initialize
+ @senders = {}
+ @socks = nil
+ end
+
+ def request(sender, tout)
+ timelimit = Time.now + tout
+ sender.send
+ while true
+ now = Time.now
+ timeout = timelimit - now
+ if timeout <= 0
+ raise ResolvTimeout
+ end
+ select_result = IO.select(@socks, nil, nil, timeout)
+ if !select_result
+ raise ResolvTimeout
+ end
+ reply, from = recv_reply(select_result[0])
+ 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
+ socks = @socks
+ @socks = nil
+ if socks
+ socks.each {|sock| sock.close }
+ end
+ end
+
+ class Sender # :nodoc:
+ def initialize(msg, data, sock)
+ @msg = msg
+ @data = data
+ @sock = sock
+ end
+ end
+
+ class UnconnectedUDP < Requester # :nodoc:
+ def initialize(*nameserver_port)
+ super()
+ @nameserver_port = nameserver_port
+ @socks_hash = {}
+ @socks = []
+ nameserver_port.each {|host, port|
+ if host.index(':')
+ bind_host = "::"
+ af = Socket::AF_INET6
+ else
+ bind_host = "0.0.0.0"
+ af = Socket::AF_INET
+ end
+ next if @socks_hash[bind_host]
+ sock = UDPSocket.new(af)
+ sock.do_not_reverse_lookup = true
+ sock.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC) if defined? Fcntl::F_SETFD
+ DNS.bind_random_port(sock, bind_host)
+ @socks << sock
+ @socks_hash[bind_host] = sock
+ }
+ end
+
+ def recv_reply(readable_socks)
+ reply, from = readable_socks[0].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')
+ sock = @socks_hash[host.index(':') ? "::" : "0.0.0.0"]
+ 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
+ is_ipv6 = host.index(':')
+ sock = UDPSocket.new(is_ipv6 ? Socket::AF_INET6 : Socket::AF_INET)
+ @socks = [sock]
+ sock.do_not_reverse_lookup = true
+ sock.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC) if defined? Fcntl::F_SETFD
+ DNS.bind_random_port(sock, is_ipv6 ? "::" : "0.0.0.0")
+ sock.connect(host, port)
+ end
+
+ def recv_reply(readable_socks)
+ reply = readable_socks[0].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, @socks[0])
+ 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)
+ @socks = [sock]
+ sock.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC) if defined? Fcntl::F_SETFD
+ @senders = {}
+ end
+
+ def recv_reply(readable_socks)
+ len = readable_socks[0].read(2).unpack('n')[0]
+ reply = @socks[0].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, @socks[0])
+ 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 = $1.to_i
+ end
+ }
+ end
+ }
+ }
+ return { :nameserver => nameserver, :search => search, :ndots => ndots }
+ end
+
+ def Config.default_config_hash(filename="/etc/resolv.conf")
+ if File.exist? filename
+ config_hash = Config.parse_resolv_conf(filename)
+ else
+ if /mswin|cygwin|mingw|bccwin/ =~ RUBY_PLATFORM
+ require 'win32/resolv'
+ search, nameserver = Win32::Resolv.get_resolv_info
+ config_hash = {}
+ config_hash[:nameserver] = nameserver if nameserver
+ config_hash[:search] = [search].flatten if search
+ end
+ end
+ config_hash || {}
+ end
+
+ def lazy_initialize
+ @mutex.synchronize {
+ unless @initialized
+ @nameserver_port = []
+ @search = nil
+ @ndots = 1
+ case @config_info
+ when nil
+ config_hash = Config.default_config_hash
+ when String
+ config_hash = Config.parse_resolv_conf(@config_info)
+ when Hash
+ config_hash = @config_info.dup
+ if String === config_hash[:nameserver]
+ config_hash[:nameserver] = [config_hash[:nameserver]]
+ end
+ if String === config_hash[:search]
+ config_hash[:search] = [config_hash[:search]]
+ end
+ else
+ raise ArgumentError.new("invalid resolv configuration: #{@config_info.inspect}")
+ end
+ if config_hash.include? :nameserver
+ @nameserver_port = config_hash[:nameserver].map {|ns| [ns, Port] }
+ end
+ if config_hash.include? :nameserver_port
+ @nameserver_port = config_hash[:nameserver_port].map {|ns, port| [ns, (port || Port)] }
+ end
+ @search = config_hash[:search] if config_hash.include? :search
+ @ndots = config_hash[:ndots] if config_hash.include? :ndots
+
+ if @nameserver_port.empty?
+ @nameserver_port << ['0.0.0.0', Port]
+ end
+ if @search
+ @search = @search.map {|arg| Label.split(arg) }
+ else
+ hostname = Socket.gethostname
+ if /\./ =~ hostname
+ @search = [Label.split($')]
+ else
+ @search = [[]]
+ end
+ end
+
+ if !@nameserver_port.kind_of?(Array) ||
+ @nameserver_port.any? {|ns_port|
+ !(Array === ns_port) ||
+ ns_port.length != 2
+ !(String === ns_port[0]) ||
+ !(Integer === ns_port[1])
+ }
+ raise ArgumentError.new("invalid nameserver config: #{@nameserver_port.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_port.length == 1
+ return @nameserver_port[0]
+ else
+ return nil
+ end
+ end
+
+ def nameserver_port
+ @nameserver_port
+ 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_port.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_port.each {|nameserver, port|
+ begin
+ yield candidate, tout, nameserver, port
+ 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 inspect
+ "\#<#{self.class}: #{@data[0, @index].inspect} #{@data[@index..-1].inspect}>"
+ 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.
+
+ Regex256 = /0
+ |1(?:[0-9][0-9]?)?
+ |2(?:[0-4][0-9]?|5[0-5]?|[6-9])?
+ |[3-9][0-9]?/x
+ Regex = /\A(#{Regex256})\.(#{Regex256})\.(#{Regex256})\.(#{Regex256})\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)
+ raise ArgumentError, 'IPv4 address must be a string'
+ end
+ unless address.length == 4
+ raise ArgumentError, "IPv4 address expects 4 bytes but #{address.length} 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
+
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