class IPAddr

IPAddr provides a set of methods to manipulate an IP address. Both IPv4 and IPv6 are supported.

Example

require 'ipaddr'

ipaddr1 = IPAddr.new "3ffe:505:2::1"

p ipaddr1                   #=> #<IPAddr: IPv6:3ffe:0505:0002:0000:0000:0000:0000:0001/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>

p ipaddr1.to_s              #=> "3ffe:505:2::1"

ipaddr2 = ipaddr1.mask(48)  #=> #<IPAddr: IPv6:3ffe:0505:0002:0000:0000:0000:0000:0000/ffff:ffff:ffff:0000:0000:0000:0000:0000>

p ipaddr2.to_s              #=> "3ffe:505:2::"

ipaddr3 = IPAddr.new "192.168.2.0/24"

p ipaddr3                   #=> #<IPAddr: IPv4:192.168.2.0/255.255.255.0>

Constants

IN4MASK

32 bit mask for IPv4

IN6FORMAT

Format string for IPv6

IN6MASK

128 bit mask for IPv6

RE_IPV4ADDRLIKE

Regexp internally used for parsing IPv4 address.

RE_IPV6ADDRLIKE_COMPRESSED

Regexp internally used for parsing IPv6 address.

RE_IPV6ADDRLIKE_FULL

Regexp internally used for parsing IPv6 address.

VERSION

Attributes

family[R]

Returns the address family of this IP address.

Public Class Methods

new(addr = '::', family = Socket::AF_UNSPEC) click to toggle source

Creates a new ipaddr object either from a human readable IP address representation in string, or from a packed in_addr value followed by an address family.

In the former case, the following are the valid formats that will be recognized: “address”, “address/prefixlen” and “address/mask”, where IPv6 address may be enclosed in square brackets (‘[’ and ‘]’). If a prefixlen or a mask is specified, it returns a masked IP address. Although the address family is determined automatically from a specified string, you can specify one explicitly by the optional second argument.

Otherwise an IP address is generated from a packed in_addr value and an address family.

The IPAddr class defines many methods and operators, and some of those, such as &, |, include? and ==, accept a string, or a packed in_addr value instead of an IPAddr object.

# File ipaddr.rb, line 591
def initialize(addr = '::', family = Socket::AF_UNSPEC)
  @mask_addr = nil
  if !addr.kind_of?(String)
    case family
    when Socket::AF_INET, Socket::AF_INET6
      set(addr.to_i, family)
      @mask_addr = (family == Socket::AF_INET) ? IN4MASK : IN6MASK
      return
    when Socket::AF_UNSPEC
      raise AddressFamilyError, "address family must be specified"
    else
      raise AddressFamilyError, "unsupported address family: #{family}"
    end
  end
  prefix, prefixlen = addr.split('/', 2)
  if prefix =~ /\A\[(.*)\]\z/i
    prefix = $1
    family = Socket::AF_INET6
  end
  if prefix =~ /\A(.*)(%\w+)\z/
    prefix = $1
    zone_id = $2
    family = Socket::AF_INET6
  end
  # It seems AI_NUMERICHOST doesn't do the job.
  #Socket.getaddrinfo(left, nil, Socket::AF_INET6, Socket::SOCK_STREAM, nil,
  #                  Socket::AI_NUMERICHOST)
  @addr = @family = nil
  if family == Socket::AF_UNSPEC || family == Socket::AF_INET
    @addr = in_addr(prefix)
    if @addr
      @family = Socket::AF_INET
    end
  end
  if !@addr && (family == Socket::AF_UNSPEC || family == Socket::AF_INET6)
    @addr = in6_addr(prefix)
    @family = Socket::AF_INET6
  end
  @zone_id = zone_id
  if family != Socket::AF_UNSPEC && @family != family
    raise AddressFamilyError, "address family mismatch"
  end
  if prefixlen
    mask!(prefixlen)
  else
    @mask_addr = (@family == Socket::AF_INET) ? IN4MASK : IN6MASK
  end
end
new_ntoh(addr) click to toggle source

Creates a new ipaddr containing the given network byte ordered string form of an IP address.

# File ipaddr.rb, line 107
def self.new_ntoh(addr)
  return new(ntop(addr))
end
ntop(addr) click to toggle source

Convert a network byte ordered string form of an IP address into human readable form.

# File ipaddr.rb, line 113
def self.ntop(addr)
  case addr.size
  when 4
    addr.unpack('C4').join('.')
  when 16
    IN6FORMAT % addr.unpack('n8')
  else
    raise AddressFamilyError, "unsupported address family"
  end
end

Public Instance Methods

&(other) click to toggle source

Returns a new ipaddr built by bitwise AND.

# File ipaddr.rb, line 125
def &(other)
  return self.clone.set(@addr & coerce_other(other).to_i)
end
<<(num) click to toggle source

Returns a new ipaddr built by bitwise left shift.

# File ipaddr.rb, line 140
def <<(num)
  return self.clone.set(addr_mask(@addr << num))
end
<=>(other) click to toggle source

Compares the ipaddr with another.

# File ipaddr.rb, line 388
def <=>(other)
  other = coerce_other(other)
rescue
  nil
else
  @addr <=> other.to_i if other.family == @family
end
==(other) click to toggle source

Returns true if two ipaddrs are equal.

# File ipaddr.rb, line 150
def ==(other)
  other = coerce_other(other)
rescue
  false
else
  @family == other.family && @addr == other.to_i
end
===(other)
Alias for: include?
>>(num) click to toggle source

Returns a new ipaddr built by bitwise right-shift.

# File ipaddr.rb, line 135
def >>(num)
  return self.clone.set(@addr >> num)
end
eql?(other) click to toggle source

Checks equality used by Hash.

# File ipaddr.rb, line 398
def eql?(other)
  return self.class == other.class && self.hash == other.hash && self == other
end
hash() click to toggle source

Returns a hash value used by Hash, Set, and Array classes

# File ipaddr.rb, line 403
def hash
  return ([@addr, @mask_addr, @zone_id].hash << 1) | (ipv4? ? 0 : 1)
end
hton() click to toggle source

Returns a network byte ordered string form of the IP address.

# File ipaddr.rb, line 228
def hton
  case @family
  when Socket::AF_INET
    return [@addr].pack('N')
  when Socket::AF_INET6
    return (0..7).map { |i|
      (@addr >> (112 - 16 * i)) & 0xffff
    }.pack('n8')
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
include?(other) click to toggle source

Returns true if the given ipaddr is in the range.

e.g.:

require 'ipaddr'
net1 = IPAddr.new("192.168.2.0/24")
net2 = IPAddr.new("192.168.2.100")
net3 = IPAddr.new("192.168.3.0")
net4 = IPAddr.new("192.168.2.0/16")
p net1.include?(net2)     #=> true
p net1.include?(net3)     #=> false
p net1.include?(net4)     #=> false
p net4.include?(net1)     #=> true
# File ipaddr.rb, line 176
def include?(other)
  other = coerce_other(other)
  return false unless other.family == family
  range = to_range
  other = other.to_range
  range.begin <= other.begin && range.end >= other.end
end
Also aliased as: ===
inspect() click to toggle source

Returns a string containing a human-readable representation of the ipaddr. (“#<IPAddr: family:address/mask>”)

# File ipaddr.rb, line 454
def inspect
  case @family
  when Socket::AF_INET
    af = "IPv4"
  when Socket::AF_INET6
    af = "IPv6"
    zone_id = @zone_id.to_s
  else
    raise AddressFamilyError, "unsupported address family"
  end
  return sprintf("#<%s: %s:%s%s/%s>", self.class.name,
                 af, _to_string(@addr), zone_id, _to_string(@mask_addr))
end
ip6_arpa() click to toggle source

Returns a string for DNS reverse lookup compatible with RFC3172.

# File ipaddr.rb, line 367
def ip6_arpa
  if !ipv6?
    raise InvalidAddressError, "not an IPv6 address: #{@addr}"
  end
  return _reverse + ".ip6.arpa"
end
ip6_int() click to toggle source

Returns a string for DNS reverse lookup compatible with RFC1886.

# File ipaddr.rb, line 375
def ip6_int
  if !ipv6?
    raise InvalidAddressError, "not an IPv6 address: #{@addr}"
  end
  return _reverse + ".ip6.int"
end
ipv4?() click to toggle source

Returns true if the ipaddr is an IPv4 address.

# File ipaddr.rb, line 242
def ipv4?
  return @family == Socket::AF_INET
end
ipv4_compat() click to toggle source

Returns a new ipaddr built by converting the native IPv4 address into an IPv4-compatible IPv6 address.

# File ipaddr.rb, line 335
def ipv4_compat
  warn "IPAddr\##{__callee__} is obsolete", uplevel: 1 if $VERBOSE
  if !ipv4?
    raise InvalidAddressError, "not an IPv4 address: #{@addr}"
  end
  return self.clone.set(@addr, Socket::AF_INET6)
end
ipv4_compat?() click to toggle source

Returns true if the ipaddr is an IPv4-compatible IPv6 address.

# File ipaddr.rb, line 307
def ipv4_compat?
  warn "IPAddr\##{__callee__} is obsolete", uplevel: 1 if $VERBOSE
  _ipv4_compat?
end
ipv4_mapped() click to toggle source

Returns a new ipaddr built by converting the native IPv4 address into an IPv4-mapped IPv6 address.

# File ipaddr.rb, line 324
def ipv4_mapped
  if !ipv4?
    raise InvalidAddressError, "not an IPv4 address: #{@addr}"
  end
  clone = self.clone.set(@addr | 0xffff00000000, Socket::AF_INET6)
  clone.instance_variable_set(:@mask_addr, @mask_addr | 0xffffffffffffffffffffffff00000000)
  clone
end
ipv4_mapped?() click to toggle source

Returns true if the ipaddr is an IPv4-mapped IPv6 address.

# File ipaddr.rb, line 302
def ipv4_mapped?
  return ipv6? && (@addr >> 32) == 0xffff
end
ipv6?() click to toggle source

Returns true if the ipaddr is an IPv6 address.

# File ipaddr.rb, line 247
def ipv6?
  return @family == Socket::AF_INET6
end
loopback?() click to toggle source

Returns true if the ipaddr is a loopback address.

# File ipaddr.rb, line 252
def loopback?
  case @family
  when Socket::AF_INET
    @addr & 0xff000000 == 0x7f000000
  when Socket::AF_INET6
    @addr == 1
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
mask(prefixlen) click to toggle source

Returns a new ipaddr built by masking IP address with the given prefixlen/netmask. (e.g. 8, 64, “255.255.255.0”, etc.)

# File ipaddr.rb, line 160
def mask(prefixlen)
  return self.clone.mask!(prefixlen)
end
native() click to toggle source

Returns a new ipaddr built by converting the IPv6 address into a native IPv4 address. If the IP address is not an IPv4-mapped or IPv4-compatible IPv6 address, returns self.

# File ipaddr.rb, line 346
def native
  if !ipv4_mapped? && !_ipv4_compat?
    return self
  end
  return self.clone.set(@addr & IN4MASK, Socket::AF_INET)
end
netmask() click to toggle source

Returns the netmask in string format e.g. 255.255.0.0

# File ipaddr.rb, line 469
def netmask
  _to_string(@mask_addr)
end
prefix() click to toggle source

Returns the prefix length in bits for the ipaddr.

# File ipaddr.rb, line 424
def prefix
  case @family
  when Socket::AF_INET
    n = IN4MASK ^ @mask_addr
    i = 32
  when Socket::AF_INET6
    n = IN6MASK ^ @mask_addr
    i = 128
  else
    raise AddressFamilyError, "unsupported address family"
  end
  while n.positive?
    n >>= 1
    i -= 1
  end
  i
end
prefix=(prefix) click to toggle source

Sets the prefix length in bits

# File ipaddr.rb, line 443
def prefix=(prefix)
  case prefix
  when Integer
    mask!(prefix)
  else
    raise InvalidPrefixError, "prefix must be an integer: #{@addr}"
  end
end
private?() click to toggle source

Returns true if the ipaddr is a private address. IPv4 addresses in 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16 as defined in RFC 1918 and IPv6 Unique Local Addresses in fc00::/7 as defined in RFC 4193 are considered private. Private IPv4 addresses in the IPv4-mapped IPv6 address range are also considered private.

# File ipaddr.rb, line 268
def private?
  case @family
  when Socket::AF_INET
    @addr & 0xff000000 == 0x0a000000 ||    # 10.0.0.0/8
      @addr & 0xfff00000 == 0xac100000 ||  # 172.16.0.0/12
      @addr & 0xffff0000 == 0xc0a80000     # 192.168.0.0/16
  when Socket::AF_INET6
    @addr & 0xfe00_0000_0000_0000_0000_0000_0000_0000 == 0xfc00_0000_0000_0000_0000_0000_0000_0000 ||
      (@addr & 0xffff_0000_0000 == 0xffff_0000_0000 && (
        @addr & 0xff000000 == 0x0a000000 ||  # ::ffff:10.0.0.0/8
        @addr & 0xfff00000 == 0xac100000 ||  # ::ffff::172.16.0.0/12
        @addr & 0xffff0000 == 0xc0a80000     # ::ffff::192.168.0.0/16
      ))
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
reverse() click to toggle source

Returns a string for DNS reverse lookup. It returns a string in RFC3172 form for an IPv6 address.

# File ipaddr.rb, line 355
def reverse
  case @family
  when Socket::AF_INET
    return _reverse + ".in-addr.arpa"
  when Socket::AF_INET6
    return ip6_arpa
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
succ() click to toggle source

Returns the successor to the ipaddr.

# File ipaddr.rb, line 383
def succ
  return self.clone.set(@addr + 1, @family)
end
to_i() click to toggle source

Returns the integer representation of the ipaddr.

# File ipaddr.rb, line 186
def to_i
  return @addr
end
to_range() click to toggle source

Creates a Range object for the network address.

# File ipaddr.rb, line 408
def to_range
  begin_addr = (@addr & @mask_addr)

  case @family
  when Socket::AF_INET
    end_addr = (@addr | (IN4MASK ^ @mask_addr))
  when Socket::AF_INET6
    end_addr = (@addr | (IN6MASK ^ @mask_addr))
  else
    raise AddressFamilyError, "unsupported address family"
  end

  self.class.new(begin_addr, @family)..self.class.new(end_addr, @family)
end
to_s() click to toggle source

Returns a string containing the IP address representation.

# File ipaddr.rb, line 191
def to_s
  str = to_string
  return str if ipv4?

  str.gsub!(/\b0{1,3}([\da-f]+)\b/i, '\1')
  loop do
    break if str.sub!(/\A0:0:0:0:0:0:0:0\z/, '::')
    break if str.sub!(/\b0:0:0:0:0:0:0\b/, ':')
    break if str.sub!(/\b0:0:0:0:0:0\b/, ':')
    break if str.sub!(/\b0:0:0:0:0\b/, ':')
    break if str.sub!(/\b0:0:0:0\b/, ':')
    break if str.sub!(/\b0:0:0\b/, ':')
    break if str.sub!(/\b0:0\b/, ':')
    break
  end
  str.sub!(/:{3,}/, '::')

  if /\A::(ffff:)?([\da-f]{1,4}):([\da-f]{1,4})\z/i =~ str
    str = sprintf('::%s%d.%d.%d.%d', $1, $2.hex / 256, $2.hex % 256, $3.hex / 256, $3.hex % 256)
  end

  str
end
to_string() click to toggle source

Returns a string containing the IP address representation in canonical form.

# File ipaddr.rb, line 217
def to_string
  str = _to_string(@addr)

  if @family == Socket::AF_INET6
    str << zone_id.to_s
  end

  return str
end
zone_id() click to toggle source

Returns the IPv6 zone identifier, if present. Raises InvalidAddressError if not an IPv6 address.

# File ipaddr.rb, line 475
def zone_id
  if @family == Socket::AF_INET6
    @zone_id
  else
    raise InvalidAddressError, "not an IPv6 address"
  end
end
zone_id=(zid) click to toggle source

Returns the IPv6 zone identifier, if present. Raises InvalidAddressError if not an IPv6 address.

# File ipaddr.rb, line 485
def zone_id=(zid)
  if @family == Socket::AF_INET6
    case zid
    when nil, /\A%(\w+)\z/
      @zone_id = zid
    else
      raise InvalidAddressError, "invalid zone identifier for address"
    end
  else
    raise InvalidAddressError, "not an IPv6 address"
  end
end
|(other) click to toggle source

Returns a new ipaddr built by bitwise OR.

# File ipaddr.rb, line 130
def |(other)
  return self.clone.set(@addr | coerce_other(other).to_i)
end
~() click to toggle source

Returns a new ipaddr built by bitwise negation.

# File ipaddr.rb, line 145
def ~
  return self.clone.set(addr_mask(~@addr))
end

Protected Instance Methods

mask!(mask) click to toggle source

Set current netmask to given mask.

# File ipaddr.rb, line 527
def mask!(mask)
  case mask
  when String
    case mask
    when /\A(0|[1-9]+\d*)\z/
      prefixlen = mask.to_i
    when /\A\d+\z/
      raise InvalidPrefixError, "leading zeros in prefix"
    else
      m = IPAddr.new(mask)
      if m.family != @family
        raise InvalidPrefixError, "address family is not same: #{@addr}"
      end
      @mask_addr = m.to_i
      n = @mask_addr ^ m.instance_variable_get(:@mask_addr)
      unless ((n + 1) & n).zero?
        raise InvalidPrefixError, "invalid mask #{mask}: #{@addr}"
      end
      @addr &= @mask_addr
      return self
    end
  else
    prefixlen = mask
  end
  case @family
  when Socket::AF_INET
    if prefixlen < 0 || prefixlen > 32
      raise InvalidPrefixError, "invalid length: #{@addr}"
    end
    masklen = 32 - prefixlen
    @mask_addr = ((IN4MASK >> masklen) << masklen)
  when Socket::AF_INET6
    if prefixlen < 0 || prefixlen > 128
      raise InvalidPrefixError, "invalid length: #{@addr}"
    end
    masklen = 128 - prefixlen
    @mask_addr = ((IN6MASK >> masklen) << masklen)
  else
    raise AddressFamilyError, "unsupported address family"
  end
  @addr = ((@addr >> masklen) << masklen)
  return self
end
set(addr, *family) click to toggle source

Set +@addr+, the internal stored ip address, to given addr. The parameter addr is validated using the first family member, which is Socket::AF_INET or Socket::AF_INET6.

# File ipaddr.rb, line 503
def set(addr, *family)
  case family[0] ? family[0] : @family
  when Socket::AF_INET
    if addr < 0 || addr > IN4MASK
      raise InvalidAddressError, "invalid address: #{@addr}"
    end
  when Socket::AF_INET6
    if addr < 0 || addr > IN6MASK
      raise InvalidAddressError, "invalid address: #{@addr}"
    end
  else
    raise AddressFamilyError, "unsupported address family"
  end
  @addr = addr
  if family[0]
    @family = family[0]
    if @family == Socket::AF_INET
      @mask_addr &= IN4MASK
    end
  end
  return self
end

Private Instance Methods

_ipv4_compat?() click to toggle source
# File ipaddr.rb, line 312
def _ipv4_compat?
  if !ipv6? || (@addr >> 32) != 0
    return false
  end
  a = (@addr & IN4MASK)
  return a != 0 && a != 1
end
_reverse() click to toggle source
# File ipaddr.rb, line 714
def _reverse
  case @family
  when Socket::AF_INET
    return (0..3).map { |i|
      (@addr >> (8 * i)) & 0xff
    }.join('.')
  when Socket::AF_INET6
    return ("%.32x" % @addr).reverse!.gsub!(/.(?!$)/, '\&.')
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
_to_string(addr) click to toggle source
# File ipaddr.rb, line 727
def _to_string(addr)
  case @family
  when Socket::AF_INET
    return (0..3).map { |i|
      (addr >> (24 - 8 * i)) & 0xff
    }.join('.')
  when Socket::AF_INET6
    return (("%.32x" % addr).gsub!(/.{4}(?!$)/, '\&:'))
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
addr_mask(addr) click to toggle source
# File ipaddr.rb, line 703
def addr_mask(addr)
  case @family
  when Socket::AF_INET
    return addr & IN4MASK
  when Socket::AF_INET6
    return addr & IN6MASK
  else
    raise AddressFamilyError, "unsupported address family"
  end
end
coerce_other(other) click to toggle source
# File ipaddr.rb, line 640
def coerce_other(other)
  case other
  when IPAddr
    other
  when String
    self.class.new(other)
  else
    self.class.new(other, @family)
  end
end
in6_addr(left) click to toggle source
# File ipaddr.rb, line 666
def in6_addr(left)
  case left
  when RE_IPV6ADDRLIKE_FULL
    if $2
      addr = in_addr($~[2,4])
      left = $1 + ':'
    else
      addr = 0
    end
    right = ''
  when RE_IPV6ADDRLIKE_COMPRESSED
    if $4
      left.count(':') <= 6 or raise InvalidAddressError, "invalid address: #{@addr}"
      addr = in_addr($~[4,4])
      left = $1
      right = $3 + '0:0'
    else
      left.count(':') <= ($1.empty? || $2.empty? ? 8 : 7) or
        raise InvalidAddressError, "invalid address: #{@addr}"
      left = $1
      right = $2
      addr = 0
    end
  else
    raise InvalidAddressError, "invalid address: #{@addr}"
  end
  l = left.split(':')
  r = right.split(':')
  rest = 8 - l.size - r.size
  if rest < 0
    return nil
  end
  (l + Array.new(rest, '0') + r).inject(0) { |i, s|
    i << 16 | s.hex
  } | addr
end
in_addr(addr) click to toggle source
# File ipaddr.rb, line 651
def in_addr(addr)
  case addr
  when Array
    octets = addr
  else
    m = RE_IPV4ADDRLIKE.match(addr) or return nil
    octets = m.captures
  end
  octets.inject(0) { |i, s|
    (n = s.to_i) < 256 or raise InvalidAddressError, "invalid address: #{@addr}"
    s.match(/\A0./) and raise InvalidAddressError, "zero-filled number in IPv4 address is ambiguous: #{@addr}"
    i << 8 | n
  }
end