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-rw-r--r--lib/resolv.rb586
1 files changed, 559 insertions, 27 deletions
diff --git a/lib/resolv.rb b/lib/resolv.rb
index 61c9c7d5cf..e36dbce259 100644
--- a/lib/resolv.rb
+++ b/lib/resolv.rb
@@ -37,6 +37,8 @@ end
class Resolv
+ VERSION = "0.4.0"
+
##
# Looks up the first IP address for +name+.
@@ -82,8 +84,8 @@ class Resolv
##
# Creates a new Resolv using +resolvers+.
- def initialize(resolvers=[Hosts.new, DNS.new])
- @resolvers = resolvers
+ def initialize(resolvers=nil, use_ipv6: nil)
+ @resolvers = resolvers || [Hosts.new, DNS.new(DNS::Config.default_config_hash.merge(use_ipv6: use_ipv6))]
end
##
@@ -192,17 +194,10 @@ class Resolv
File.open(@filename, 'rb') {|f|
f.each {|line|
line.sub!(/#.*/, '')
- addr, hostname, *aliases = line.split(/\s+/)
+ addr, *hostnames = line.split(/\s+/)
next unless addr
- @addr2name[addr] = [] unless @addr2name.include? addr
- @addr2name[addr] << hostname
- @addr2name[addr] += aliases
- @name2addr[hostname] = [] unless @name2addr.include? hostname
- @name2addr[hostname] << addr
- aliases.each {|n|
- @name2addr[n] = [] unless @name2addr.include? n
- @name2addr[n] << addr
- }
+ (@addr2name[addr] ||= []).concat(hostnames)
+ hostnames.each {|hostname| (@name2addr[hostname] ||= []) << addr}
}
}
@name2addr.each {|name, arr| arr.reverse!}
@@ -310,6 +305,8 @@ class Resolv
# 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.
+ # :raise_timeout_errors can be used to raise timeout errors
+ # as exceptions instead of treating the same as an NXDOMAIN response.
#
# The value of :nameserver should be an address string or
# an array of address strings.
@@ -406,6 +403,11 @@ class Resolv
end
def use_ipv6? # :nodoc:
+ use_ipv6 = @config.use_ipv6?
+ unless use_ipv6.nil?
+ return use_ipv6
+ end
+
begin
list = Socket.ip_address_list
rescue NotImplementedError
@@ -748,7 +750,7 @@ class Resolv
next if @socks_hash[bind_host]
begin
sock = UDPSocket.new(af)
- rescue Errno::EAFNOSUPPORT
+ rescue Errno::EAFNOSUPPORT, Errno::EPROTONOSUPPORT
next # The kernel doesn't support the address family.
end
@socks << sock
@@ -965,7 +967,7 @@ class Resolv
next unless keyword
case keyword
when 'nameserver'
- nameserver += args
+ nameserver.concat(args)
when 'domain'
next if args.empty?
search = [args[0]]
@@ -1004,6 +1006,7 @@ class Resolv
@mutex.synchronize {
unless @initialized
@nameserver_port = []
+ @use_ipv6 = nil
@search = nil
@ndots = 1
case @config_info
@@ -1028,8 +1031,12 @@ class Resolv
if config_hash.include? :nameserver_port
@nameserver_port = config_hash[:nameserver_port].map {|ns, port| [ns, (port || Port)] }
end
+ if config_hash.include? :use_ipv6
+ @use_ipv6 = config_hash[:use_ipv6]
+ end
@search = config_hash[:search] if config_hash.include? :search
@ndots = config_hash[:ndots] if config_hash.include? :ndots
+ @raise_timeout_errors = config_hash[:raise_timeout_errors]
if @nameserver_port.empty?
@nameserver_port << ['0.0.0.0', Port]
@@ -1083,6 +1090,10 @@ class Resolv
@nameserver_port
end
+ def use_ipv6?
+ @use_ipv6
+ end
+
def generate_candidates(name)
candidates = nil
name = Name.create(name)
@@ -1116,6 +1127,7 @@ class Resolv
def resolv(name)
candidates = generate_candidates(name)
timeouts = @timeouts || generate_timeouts
+ timeout_error = false
begin
candidates.each {|candidate|
begin
@@ -1127,11 +1139,13 @@ class Resolv
end
}
}
+ timeout_error = true
raise ResolvError.new("DNS resolv timeout: #{name}")
rescue NXDomain
end
}
rescue ResolvError
+ raise if @raise_timeout_errors && timeout_error
end
end
@@ -1487,14 +1501,14 @@ class Resolv
}
end
- def put_name(d)
- put_labels(d.to_a)
+ def put_name(d, compress: true)
+ put_labels(d.to_a, compress: compress)
end
- def put_labels(d)
+ def put_labels(d, compress: true)
d.each_index {|i|
domain = d[i..-1]
- if idx = @names[domain]
+ if compress && idx = @names[domain]
self.put_pack("n", 0xc000 | idx)
return
else
@@ -1518,13 +1532,15 @@ class Resolv
id, flag, qdcount, ancount, nscount, arcount =
msg.get_unpack('nnnnnn')
o.id = id
+ o.tc = (flag >> 9) & 1
+ o.rcode = flag & 15
+ return o unless o.tc.zero?
+
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)
@@ -1616,6 +1632,14 @@ class Resolv
strings
end
+ def get_list
+ [].tap do |values|
+ while @index < @limit
+ values << yield
+ end
+ end
+ end
+
def get_name
return Name.new(self.get_labels)
end
@@ -1677,6 +1701,378 @@ class Resolv
end
##
+ # SvcParams for service binding RRs. [RFC9460]
+
+ class SvcParams
+ include Enumerable
+
+ ##
+ # Create a list of SvcParams with the given initial content.
+ #
+ # +params+ has to be an enumerable of +SvcParam+s.
+ # If its content has +SvcParam+s with the duplicate key,
+ # the one appears last takes precedence.
+
+ def initialize(params = [])
+ @params = {}
+
+ params.each do |param|
+ add param
+ end
+ end
+
+ ##
+ # Get SvcParam for the given +key+ in this list.
+
+ def [](key)
+ @params[canonical_key(key)]
+ end
+
+ ##
+ # Get the number of SvcParams in this list.
+
+ def count
+ @params.count
+ end
+
+ ##
+ # Get whether this list is empty.
+
+ def empty?
+ @params.empty?
+ end
+
+ ##
+ # Add the SvcParam +param+ to this list, overwriting the existing one with the same key.
+
+ def add(param)
+ @params[param.class.key_number] = param
+ end
+
+ ##
+ # Remove the +SvcParam+ with the given +key+ and return it.
+
+ def delete(key)
+ @params.delete(canonical_key(key))
+ end
+
+ ##
+ # Enumerate the +SvcParam+s in this list.
+
+ def each(&block)
+ return enum_for(:each) unless block
+ @params.each_value(&block)
+ end
+
+ def encode(msg) # :nodoc:
+ @params.keys.sort.each do |key|
+ msg.put_pack('n', key)
+ msg.put_length16 do
+ @params.fetch(key).encode(msg)
+ end
+ end
+ end
+
+ def self.decode(msg) # :nodoc:
+ params = msg.get_list do
+ key, = msg.get_unpack('n')
+ msg.get_length16 do
+ SvcParam::ClassHash[key].decode(msg)
+ end
+ end
+
+ return self.new(params)
+ end
+
+ private
+
+ def canonical_key(key) # :nodoc:
+ case key
+ when Integer
+ key
+ when /\Akey(\d+)\z/
+ Integer($1)
+ when Symbol
+ SvcParam::ClassHash[key].key_number
+ else
+ raise TypeError, 'key must be either String or Symbol'
+ end
+ end
+ end
+
+
+ ##
+ # Base class for SvcParam. [RFC9460]
+
+ class SvcParam
+
+ ##
+ # Get the presentation name of the SvcParamKey.
+
+ def self.key_name
+ const_get(:KeyName)
+ end
+
+ ##
+ # Get the registered number of the SvcParamKey.
+
+ def self.key_number
+ const_get(:KeyNumber)
+ end
+
+ ClassHash = Hash.new do |h, key| # :nodoc:
+ case key
+ when Integer
+ Generic.create(key)
+ when /\Akey(?<key>\d+)\z/
+ Generic.create(key.to_int)
+ when Symbol
+ raise KeyError, "unknown key #{key}"
+ else
+ raise TypeError, 'key must be either String or Symbol'
+ end
+ end
+
+ ##
+ # Generic SvcParam abstract class.
+
+ class Generic < SvcParam
+
+ ##
+ # SvcParamValue in wire-format byte string.
+
+ attr_reader :value
+
+ ##
+ # Create generic SvcParam
+
+ def initialize(value)
+ @value = value
+ end
+
+ def encode(msg) # :nodoc:
+ msg.put_bytes(@value)
+ end
+
+ def self.decode(msg) # :nodoc:
+ return self.new(msg.get_bytes)
+ end
+
+ def self.create(key_number)
+ c = Class.new(Generic)
+ key_name = :"key#{key_number}"
+ c.const_set(:KeyName, key_name)
+ c.const_set(:KeyNumber, key_number)
+ self.const_set(:"Key#{key_number}", c)
+ ClassHash[key_name] = ClassHash[key_number] = c
+ return c
+ end
+ end
+
+ ##
+ # "mandatory" SvcParam -- Mandatory keys in service binding RR
+
+ class Mandatory < SvcParam
+ KeyName = :mandatory
+ KeyNumber = 0
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ ##
+ # Mandatory keys.
+
+ attr_reader :keys
+
+ ##
+ # Initialize "mandatory" ScvParam.
+
+ def initialize(keys)
+ @keys = keys.map(&:to_int)
+ end
+
+ def encode(msg) # :nodoc:
+ @keys.sort.each do |key|
+ msg.put_pack('n', key)
+ end
+ end
+
+ def self.decode(msg) # :nodoc:
+ keys = msg.get_list { msg.get_unpack('n')[0] }
+ return self.new(keys)
+ end
+ end
+
+ ##
+ # "alpn" SvcParam -- Additional supported protocols
+
+ class ALPN < SvcParam
+ KeyName = :alpn
+ KeyNumber = 1
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ ##
+ # Supported protocol IDs.
+
+ attr_reader :protocol_ids
+
+ ##
+ # Initialize "alpn" ScvParam.
+
+ def initialize(protocol_ids)
+ @protocol_ids = protocol_ids.map(&:to_str)
+ end
+
+ def encode(msg) # :nodoc:
+ msg.put_string_list(@protocol_ids)
+ end
+
+ def self.decode(msg) # :nodoc:
+ return self.new(msg.get_string_list)
+ end
+ end
+
+ ##
+ # "no-default-alpn" SvcParam -- No support for default protocol
+
+ class NoDefaultALPN < SvcParam
+ KeyName = :'no-default-alpn'
+ KeyNumber = 2
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ def encode(msg) # :nodoc:
+ # no payload
+ end
+
+ def self.decode(msg) # :nodoc:
+ return self.new
+ end
+ end
+
+ ##
+ # "port" SvcParam -- Port for alternative endpoint
+
+ class Port < SvcParam
+ KeyName = :port
+ KeyNumber = 3
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ ##
+ # Port number.
+
+ attr_reader :port
+
+ ##
+ # Initialize "port" ScvParam.
+
+ def initialize(port)
+ @port = port.to_int
+ end
+
+ def encode(msg) # :nodoc:
+ msg.put_pack('n', @port)
+ end
+
+ def self.decode(msg) # :nodoc:
+ port, = msg.get_unpack('n')
+ return self.new(port)
+ end
+ end
+
+ ##
+ # "ipv4hint" SvcParam -- IPv4 address hints
+
+ class IPv4Hint < SvcParam
+ KeyName = :ipv4hint
+ KeyNumber = 4
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ ##
+ # Set of IPv4 addresses.
+
+ attr_reader :addresses
+
+ ##
+ # Initialize "ipv4hint" ScvParam.
+
+ def initialize(addresses)
+ @addresses = addresses.map {|address| IPv4.create(address) }
+ end
+
+ def encode(msg) # :nodoc:
+ @addresses.each do |address|
+ msg.put_bytes(address.address)
+ end
+ end
+
+ def self.decode(msg) # :nodoc:
+ addresses = msg.get_list { IPv4.new(msg.get_bytes(4)) }
+ return self.new(addresses)
+ end
+ end
+
+ ##
+ # "ipv6hint" SvcParam -- IPv6 address hints
+
+ class IPv6Hint < SvcParam
+ KeyName = :ipv6hint
+ KeyNumber = 6
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ ##
+ # Set of IPv6 addresses.
+
+ attr_reader :addresses
+
+ ##
+ # Initialize "ipv6hint" ScvParam.
+
+ def initialize(addresses)
+ @addresses = addresses.map {|address| IPv6.create(address) }
+ end
+
+ def encode(msg) # :nodoc:
+ @addresses.each do |address|
+ msg.put_bytes(address.address)
+ end
+ end
+
+ def self.decode(msg) # :nodoc:
+ addresses = msg.get_list { IPv6.new(msg.get_bytes(16)) }
+ return self.new(addresses)
+ end
+ end
+
+ ##
+ # "dohpath" SvcParam -- DNS over HTTPS path template [RFC9461]
+
+ class DoHPath < SvcParam
+ KeyName = :dohpath
+ KeyNumber = 7
+ ClassHash[KeyName] = ClassHash[KeyNumber] = self # :nodoc:
+
+ ##
+ # URI template for DoH queries.
+
+ attr_reader :template
+
+ ##
+ # Initialize "dohpath" ScvParam.
+
+ def initialize(template)
+ @template = template.encode('utf-8')
+ end
+
+ def encode(msg) # :nodoc:
+ msg.put_bytes(@template)
+ end
+
+ def self.decode(msg) # :nodoc:
+ template = msg.get_bytes.force_encoding('utf-8')
+ return self.new(template)
+ end
+ end
+ end
+
+ ##
# A DNS query abstract class.
class Query
@@ -2141,8 +2537,70 @@ class Resolv
TypeValue = 255 # :nodoc:
end
+ ##
+ # CAA resource record defined in RFC 8659
+ #
+ # These records identify certificate authority allowed to issue
+ # certificates for the given domain.
+
+ class CAA < Resource
+ TypeValue = 257
+
+ ##
+ # Creates a new CAA for +flags+, +tag+ and +value+.
+
+ def initialize(flags, tag, value)
+ unless (0..255) === flags
+ raise ArgumentError.new('flags must be an Integer between 0 and 255')
+ end
+ unless (1..15) === tag.bytesize
+ raise ArgumentError.new('length of tag must be between 1 and 15')
+ end
+
+ @flags = flags
+ @tag = tag
+ @value = value
+ end
+
+ ##
+ # Flags for this proprty:
+ # - Bit 0 : 0 = not critical, 1 = critical
+
+ attr_reader :flags
+
+ ##
+ # Property tag ("issue", "issuewild", "iodef"...).
+
+ attr_reader :tag
+
+ ##
+ # Property value.
+
+ attr_reader :value
+
+ ##
+ # Whether the critical flag is set on this property.
+
+ def critical?
+ flags & 0x80 != 0
+ end
+
+ def encode_rdata(msg) # :nodoc:
+ msg.put_pack('C', @flags)
+ msg.put_string(@tag)
+ msg.put_bytes(@value)
+ end
+
+ def self.decode_rdata(msg) # :nodoc:
+ flags, = msg.get_unpack('C')
+ tag = msg.get_string
+ value = msg.get_bytes
+ self.new flags, tag, value
+ end
+ end
+
ClassInsensitiveTypes = [ # :nodoc:
- NS, CNAME, SOA, PTR, HINFO, MINFO, MX, TXT, LOC, ANY
+ NS, CNAME, SOA, PTR, HINFO, MINFO, MX, TXT, LOC, ANY, CAA
]
##
@@ -2328,7 +2786,7 @@ class Resolv
msg.put_pack("n", @priority)
msg.put_pack("n", @weight)
msg.put_pack("n", @port)
- msg.put_name(@target)
+ msg.put_name(@target, compress: false)
end
def self.decode_rdata(msg) # :nodoc:
@@ -2339,6 +2797,84 @@ class Resolv
return self.new(priority, weight, port, target)
end
end
+
+ ##
+ # Common implementation for SVCB-compatible resource records.
+
+ class ServiceBinding
+
+ ##
+ # Create a service binding resource record.
+
+ def initialize(priority, target, params = [])
+ @priority = priority.to_int
+ @target = Name.create(target)
+ @params = SvcParams.new(params)
+ end
+
+ ##
+ # The priority of this target host.
+ #
+ # The range is 0-65535.
+ # If set to 0, this RR is in AliasMode. Otherwise, it is in ServiceMode.
+
+ attr_reader :priority
+
+ ##
+ # The domain name of the target host.
+
+ attr_reader :target
+
+ ##
+ # The service parameters for the target host.
+
+ attr_reader :params
+
+ ##
+ # Whether this RR is in AliasMode.
+
+ def alias_mode?
+ self.priority == 0
+ end
+
+ ##
+ # Whether this RR is in ServiceMode.
+
+ def service_mode?
+ !alias_mode?
+ end
+
+ def encode_rdata(msg) # :nodoc:
+ msg.put_pack("n", @priority)
+ msg.put_name(@target, compress: false)
+ @params.encode(msg)
+ end
+
+ def self.decode_rdata(msg) # :nodoc:
+ priority, = msg.get_unpack("n")
+ target = msg.get_name
+ params = SvcParams.decode(msg)
+ return self.new(priority, target, params)
+ end
+ end
+
+ ##
+ # SVCB resource record [RFC9460]
+
+ class SVCB < ServiceBinding
+ TypeValue = 64
+ ClassValue = IN::ClassValue
+ ClassHash[[TypeValue, ClassValue]] = self # :nodoc:
+ end
+
+ ##
+ # HTTPS resource record [RFC9460]
+
+ class HTTPS < ServiceBinding
+ TypeValue = 65
+ ClassValue = IN::ClassValue
+ ClassHash[[TypeValue, ClassValue]] = self # :nodoc:
+ end
end
end
end
@@ -2558,11 +3094,7 @@ class Resolv
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(:|$)/, '::')
- end
- return address
+ sprintf("%x:%x:%x:%x:%x:%x:%x:%x", *@address.unpack("nnnnnnnn")).sub(/(^|:)0(:0)+(:|$)/, '::')
end
def inspect # :nodoc:
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-19 10:38:56 +0000