class IPAddress::IPv6

Name

IPAddress::IPv6 - IP version 6 address manipulation library

Synopsis

require 'ipaddress'

Description

Class IPAddress::IPv6 is used to handle IPv6 type addresses.

IPv6 addresses

IPv6 addresses are 128 bits long, in contrast with IPv4 addresses which are only 32 bits long. An IPv6 address is generally written as eight groups of four hexadecimal digits, each group representing 16 bits or two octect. For example, the following is a valid IPv6 address:

2001:0db8:0000:0000:0008:0800:200c:417a

Letters in an IPv6 address are usually written downcase, as per RFC. You can create a new IPv6 object using uppercase letters, but they will be converted.

Compression

Since IPv6 addresses are very long to write, there are some semplifications and compressions that you can use to shorten them.

Using compression, the IPv6 address written above can be shorten into the following, equivalent, address

2001:db8::8:800:200c:417a

This short version is often used in human representation.

Network Mask

As we used to do with IPv4 addresses, an IPv6 address can be written using the prefix notation to specify the subnet mask:

2001:db8::8:800:200c:417a/64

The /64 part means that the first 64 bits of the address are representing the network portion, and the last 64 bits are the host portion.

Constants

IN6FORMAT

Format string to pretty print IPv6 addresses

Public Class Methods

compress(str) click to toggle source

Compress an IPv6 address in its compressed form

IPAddress::IPv6.compress "2001:0DB8:0000:CD30:0000:0000:0000:0000"
  #=> "2001:db8:0:cd30::"
# File lib/ipaddress_2/ipv6.rb, line 925
def self.compress(str)
  self.new(str).compressed
end
expand(str) click to toggle source

Expands an IPv6 address in the canocical form

IPAddress::IPv6.expand "2001:0DB8:0:CD30::"
  #=> "2001:0DB8:0000:CD30:0000:0000:0000:0000"
# File lib/ipaddress_2/ipv6.rb, line 915
def self.expand(str)
  self.new(str).address
end
groups(str) click to toggle source

Extract 16 bits groups from a string

# File lib/ipaddress_2/ipv6.rb, line 974
def self.groups(str)
  l, r = if str =~ /^(.*)::(.*)$/
           [$1,$2].map {|i| i.split ":"}
         else
           [str.split(":"),[]]
         end
  (l + Array.new(8-l.size-r.size, '0') + r).map {|i| i.hex}
end
new(str) click to toggle source

Creates a new IPv6 address object.

An IPv6 address can be expressed in any of the following forms:

  • “2001:0db8:0000:0000:0008:0800:200C:417A”: IPv6 address with no compression

  • “2001:db8:0:0:8:800:200C:417A”: IPv6 address with leading zeros compression

  • “2001:db8::8:800:200C:417A”: IPv6 address with full compression

In all these 3 cases, a new IPv6 address object will be created, using the default subnet mask /128

You can also specify the subnet mask as with IPv4 addresses:

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 89
def initialize(str)
  raise ArgumentError, "Nil IP" unless str
  ip, netmask = str.split("/")

  if str =~ /:.+\./
    raise ArgumentError, "Please use #{self.class}::Mapped for IPv4 mapped addresses"
  end

  if IPAddress.valid_ipv6?(ip)
    @groups = self.class.groups(ip)
    @address = IN6FORMAT % @groups
    @compressed = compress_address
  else
    raise ArgumentError, "Invalid IP #{ip.inspect}"
  end

  @prefix = Prefix128.new(netmask ? netmask : 128)
  @allocator = 0

end
parse_data(str) click to toggle source

Creates a new IPv6 object from binary data, like the one you get from a network stream.

For example, on a network stream the IP

"2001:db8::8:800:200c:417a"

is represented with the binary data

" \001\r\270\000\000\000\000\000\b\b\000 \fAz"

With that data you can create a new IPv6 object:

ip6 = IPAddress::IPv6::parse_data " \001\r\270\000\000\000\000\000\b\b\000 \fAz"
ip6.prefix = 64

ip6.to_s
  #=> "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 1003
def self.parse_data(str)
  self.new(IN6FORMAT % str.unpack("n8"))
end
parse_hex(hex, prefix=128) click to toggle source

Creates a new IPv6 object from a number expressed in hexdecimal format:

ip6 = IPAddress::IPv6::parse_hex("20010db80000000000080800200c417a")
ip6.prefix = 64

ip6.to_string
  #=> "2001:db8::8:800:200c:417a/64"

The prefix parameter is optional:

ip6 = IPAddress::IPv6::parse_hex("20010db80000000000080800200c417a", 64)

ip6.to_string
  #=> "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 1046
def self.parse_hex(hex, prefix=128)
  self.parse_u128(hex.hex, prefix)
end
parse_u128(u128, prefix=128) click to toggle source

Creates a new IPv6 object from an unsigned 128 bits integer.

ip6 = IPAddress::IPv6::parse_u128(42540766411282592856906245548098208122)
ip6.prefix = 64

ip6.to_string
  #=> "2001:db8::8:800:200c:417a/64"

The prefix parameter is optional:

ip6 = IPAddress::IPv6::parse_u128(42540766411282592856906245548098208122, 64)

ip6.to_string
  #=> "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 1024
def self.parse_u128(u128, prefix=128)
  str = IN6FORMAT % (0..7).map{|i| (u128>>(112-16*i))&0xffff}
  self.new(str + "/#{prefix}")
end
summarize(*args) click to toggle source

Summarization (or aggregation) is the process when two or more networks are taken together to check if a supernet, including all and only these networks, exists. If it exists then this supernet is called the summarized (or aggregated) network.

It is very important to understand that summarization can only occur if there are no holes in the aggregated network, or, in other words, if the given networks fill completely the address space of the supernet. So the two rules are:

1) The aggregate network must contain all the IP addresses of the

original networks;

2) The aggregate network must contain only the IP addresses of the

original networks;

A few examples will help clarify the above. Let's consider for instance the following two networks:

ip1 = IPAddress("2001:db8:8:800::1/64")
ip2 = IPAddress("2001:0db8:8:801::2/64")

These two networks can be expressed using only one IP address network if we change the prefix. Let Ruby do the work:

IPAddress::IPv6::summarize(ip1,ip2).to_s
  #=> "2001:db8:8:800::/63"

We note how the network “2001:db8:8:800::/63” includes all the addresses specified in the above networks, and (more important) includes ONLY those addresses.

If we summarized ip1 and ip2 with the following network:

"2001:db8::/32"

we would have satisfied rule #1 above, but not rule #2. So “2001:db8::/32” is not an aggregate network for ip1 and ip2.

If it's not possible to compute a single aggregated network for all the original networks, the method returns an array with all the aggregate networks found. For example, the following four networks can be aggregated in a single /22:

ip1 = IPAddress("2001:db8:8:800::1/64")
ip2 = IPAddress("2001:db8:8:801::1/64")
ip3 = IPAddress("2001:db8:8:802::1/64")
ip4 = IPAddress("2001:db8:8:803::1/64")

IPAddress::IPv6::summarize(ip1,ip2,ip3,ip4).to_string
  #=> "2001:db8:8:800::/62",

But the following networks can't be summarized in a single network:

ip1 = IPAddress("2001:db8:8:801::1/64")
ip2 = IPAddress("2001:db8:8:802::1/64")
ip3 = IPAddress("2001:db8:8:803::1/64")
ip4 = IPAddress("2001:db8:8:804::1/64")

IPAddress::IPv6::summarize(ip1,ip2,ip3,ip4).map{|i| i.to_string}
  #=> ["2001:db8:8:801::/64","2001:db8:8:802::/63","2001:db8:8:804::/64"]
# File lib/ipaddress_2/ipv6.rb, line 1112
def self.summarize(*args)
  # one network? no need to summarize
  return [args.first.network] if args.size == 1
  args_size = args.size 

  i = 0
  result = args.sort.map{|ip| ip.network}
  while i < result.size-1
    sum = result[i] + result[i+1]
    result[i..i+1] = sum.first if sum.size == 1
    i += 1
  end

  result.flatten!
  if result.size == args_size
    # nothing more to summarize
    return result
  else
    # keep on summarizing
    return self.summarize(*result)
  end
end

Public Instance Methods

+(oth) click to toggle source

Returns a new IPv6 object which is the result of the summarization, if possible, of the two objects

Example:

ip1 = IPAddress("172.16.10.1/24")
ip2 = IPAddress("172.16.11.2/24")

p (ip1 + ip2).map {|i| i.to_string}
  #=> ["172.16.10.0/23"]

If the networks are not contiguous, returns the two network numbers from the objects

ip1 = IPAddress("10.0.0.1/24")
ip2 = IPAddress("10.0.2.1/24")

p (ip1 + ip2).map {|i| i.to_string}
  #=> ["10.0.0.0/24","10.0.2.0/24"]
# File lib/ipaddress_2/ipv6.rb, line 733
def +(oth)
  aggregate(*[self,oth].sort.map{|i| i.network})
end
/(subnets=2)
Alias for: split
<=>(oth) click to toggle source

Spaceship operator to compare IPv6 objects

Comparing IPv6 addresses is useful to ordinate them into lists that match our intuitive perception of ordered IP addresses.

The first comparison criteria is the u128 value. For example, 2001:db8:1::1 will be considered to be less than 2001:db8:2::1, because, in a ordered list, we expect 2001:db8:1::1 to come before 2001:db8:2::1.

The second criteria, in case two IPv6 objects have identical addresses, is the prefix. An higher prefix will be considered greater than a lower prefix. This is because we expect to see 2001:db8:1::1/64 come before 2001:db8:1::1/65

Example:

ip1 = IPAddress "2001:db8:1::1/64"
ip2 = IPAddress "2001:db8:2::1/64"
ip3 = IPAddress "2001:db8:1::1/65"

ip1 < ip2
  #=> true
ip1 < ip3
  #=> false

[ip1,ip2,ip3].sort.map{|i| i.to_string}
  #=> ["2001:db8:1::1/64","2001:db8:1::1/65","2001:db8:2::1/64"]
# File lib/ipaddress_2/ipv6.rb, line 890
def <=>(oth)
  return nil unless oth.is_a?(self.class)
  return prefix <=> oth.prefix if to_u128 == oth.to_u128
  to_u128 <=> oth.to_u128
end
[](index) click to toggle source

Returns the 16-bits value specified by index

ip = IPAddress("2001:db8::8:800:200c:417a/64")

ip[0]
  #=> 8193
ip[1]
  #=> 3512
ip[2]
  #=> 0
ip[3]
  #=> 0
# File lib/ipaddress_2/ipv6.rb, line 320
def [](index)
  @groups[index]
end
Also aliased as: group
[]=(index, value) click to toggle source

Updated the octet specified at index

# File lib/ipaddress_2/ipv6.rb, line 328
def []=(index, value)
  @groups[index] = value
  initialize("#{IN6FORMAT % @groups}/#{prefix}")
end
Also aliased as: group=
add(oth, validating=true) click to toggle source

Returns a new IPv6 object which is the result of advancing this IP address by a given value. In other words, this arithmetically adds IP addresses.

Will raise an error if the resulting address is in a different subnet, except validating is set to false.

Example:

ip = IPAddress::IPv6.new("fc42:1337::/64")
ip.add(5).to_string
  #=> "fc42:1337::5/64"
# File lib/ipaddress_2/ipv6.rb, line 411
def add(oth, validating=true)
  oth = oth.to_i if oth.kind_of? IPAddress::IPv6 # oth shall be integer
  
  new_obj = self.class.parse_u128(self.to_i + oth, prefix)
  
  if validating and self.network_u128 != new_obj.network_u128
    raise RuntimeError, "Subnet (/#{@prefix}) is not large enough."
  end
  
  new_obj
end
address() click to toggle source

Returns the IPv6 address in uncompressed form:

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.address
  #=> "2001:0db8:0000:0000:0008:0800:200c:417a"
# File lib/ipaddress_2/ipv6.rb, line 118
def address
  @address
end
advance_network(amount) click to toggle source

Returns the network address of the n-th network succeeding this one.

Example:

ip = IPAddress::IPv6.new("fc42:1337:0:0::/64")
ip.advance_network(5).to_string
  #=> "fc42:1337:0:5::/64"
# File lib/ipaddress_2/ipv6.rb, line 449
def advance_network(amount)
  IPAddress::IPv6.parse_u128(self.network.to_i + amount*self.size, @prefix)
end
allocate(skip=0) click to toggle source

Allocates a new ip from the current subnet. Optional skip parameter can be used to skip addresses.

Will raise StopIteration exception when all addresses have been allocated

Example:

ip = IPAddress("10.0.0.0/24")
ip.allocate
  #=> "10.0.0.1/24"
ip.allocate
  #=> "10.0.0.2/24"
ip.allocate(2)
  #=> "10.0.0.5/24"

Uses an internal @allocator which tracks the state of allocated addresses.

# File lib/ipaddress_2/ipv6.rb, line 1155
def allocate(skip=0)
    @allocator += 1 + skip

    next_ip = network_u128+@allocator
    if next_ip > broadcast_u128
        raise StopIteration
    end
    self.class.parse_u128(next_ip, @prefix)
end
arpa()
Alias for: reverse
as_json() click to toggle source

When serializing to JSON format, just use the string representation

ip = IPAddress "2001:db8::8:800:200c:417a/64"

ip.as_json
  #=> "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 129
def as_json
  to_string
end
bits() click to toggle source

Returns the address portion of an IP in binary format, as a string containing a sequence of 0 and 1

ip6 = IPAddress("2001:db8::8:800:200c:417a")

ip6.bits
  #=> "0010000000000001000011011011100000 [...] "
# File lib/ipaddress_2/ipv6.rb, line 905
def bits
  data.unpack("B*").first
end
broadcast() click to toggle source

Returns the broadcast address for the given IP. As this is IPv6 it is just the last IP

ip = IPAddress("2001:db8:8:800::/64")

ip.broadcast.to_s
  #=> "2001:db8:8:800::"
# File lib/ipaddress_2/ipv6.rb, line 963
def broadcast
  if prefix == 128
    return self
  else
    IPAddress::IPv6::parse_u128(broadcast_u128)
  end
end
broadcast_u128() click to toggle source

Returns the broadcast address in Unsigned 128bits format

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.broadcast_u128
  #=> 42540766411282592875350729025363378175

Please note that there is no Broadcast concept in IPv6 addresses as in IPv4 addresses, and this method is just an helper to other functions.

# File lib/ipaddress_2/ipv6.rb, line 583
def broadcast_u128
  network_u128 + size - 1
end
compressed() click to toggle source

Compressed form of the IPv6 address

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.compressed
  #=> "2001:db8::8:800:200c:417a"
# File lib/ipaddress_2/ipv6.rb, line 652
def compressed
  @compressed
end
data() click to toggle source

Returns the address portion of an IPv6 object in a network byte order format.

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.data
  #=> " \001\r\270\000\000\000\000\000\b\b\000 \fAz"

It is usually used to include an IP address in a data packet to be sent over a socket

a = Socket.open(params) # socket details here
ip6 = IPAddress "2001:db8::8:800:200c:417a/64"
binary_data = ["Address: "].pack("a*") + ip.data

# Send binary data
a.puts binary_data
# File lib/ipaddress_2/ipv6.rb, line 365
def data
  @groups.pack("n8")
end
each() { |class.parse_u128(i, prefix)| ... } click to toggle source

Iterates over all the IP addresses for the given network (or IP address).

The object yielded is a new IPv6 object created from the iteration.

ip6 = IPAddress("2001:db8::4/125")

ip6.each do |i|
  p i.compressed
end
  #=> "2001:db8::"
  #=> "2001:db8::1"
  #=> "2001:db8::2"
  #=> "2001:db8::3"
  #=> "2001:db8::4"
  #=> "2001:db8::5"
  #=> "2001:db8::6"
  #=> "2001:db8::7"

WARNING: if the host portion is very large, this method can be very slow and possibly hang your system!

# File lib/ipaddress_2/ipv6.rb, line 823
def each
  (network_u128..broadcast_u128).each do |i|
    yield self.class.parse_u128(i, @prefix)
  end
end
find_adjacent_subnet() click to toggle source

Finds the adjacent block to a subnet.

Example:

ip = IPAddress("2001:db8::/32")
ip.find_adjacent_subnet
  #=> "2001:db9::/32"
# File lib/ipaddress_2/ipv6.rb, line 1174
def find_adjacent_subnet
  return false if prefix == 0
  current_subnet = to_string
  self.prefix = @prefix - 1
  adjacent_subnet = (split.map{|i| i.to_string} - [current_subnet])[0]
  self.prefix = @prefix + 1
  return adjacent_subnet
end
first() click to toggle source

Returns a new IPv6 object with the first host IP address in the range.

Example: given the 2001:db8:8:800::/64 network, the first

host IP address is 2001:db8:8:800

ip = IPAddress(“2001:db8:8:800::/64”)

ip.first.to_s

#=> "2001:db8:8:800::"

The object IP doesn't need to be a network: the method automatically gets the network number from it

ip = IPAddress("2001:db8:9:800::2/64")

ip.first.to_s
  #=> "2001:db8:9:800::"
# File lib/ipaddress_2/ipv6.rb, line 269
def first
  if prefix == 128
    return self
  else
    IPAddress::IPv6::parse_u128(network_u128)
  end
end
group(index)
Alias for: []
group=(index, value)
Alias for: []=
groups() click to toggle source

Returns an array with the 16 bits groups in decimal format:

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.groups
  #=> [8193, 3512, 0, 0, 8, 2048, 8204, 16762]
# File lib/ipaddress_2/ipv6.rb, line 142
def groups
  @groups
end
hexs() click to toggle source

Returns an array of the 16 bits groups in hexdecimal format:

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.hexs
  #=> ["2001", "0db8", "0000", "0000", "0008", "0800", "200c", "417a"]

Not to be confused with the similar IPv6#to_hex method.

# File lib/ipaddress_2/ipv6.rb, line 380
def hexs
  @address.split(":")
end
hostpart() click to toggle source

Returns a new IPv6 object containing only the host part of this IP.

ip = IPAddress::IPv6.new("fc42:1337:0:5::7/64")

ip.hostpart.to_s
  #=> "::7"
# File lib/ipaddress_2/ipv6.rb, line 497
def hostpart
  self.class.parse_u128(hostpart_u128, 128)
end
hostpart_u128() click to toggle source

Returns this address' host part in unsigned 128bits format

ip = IPAddress::IPv6.new("fc42:1337:0:5::7/64")

ip.host_u128
  #=> 7
# File lib/ipaddress_2/ipv6.rb, line 567
def hostpart_u128
  to_u128 & ~@prefix.to_u128
end
include?(oth) click to toggle source

Checks whether a subnet includes the given IP address.

Example:

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"
addr = IPAddress "2001:db8::8:800:200c:1/128"

ip6.include? addr
  #=> true

ip6.include? IPAddress("2001:db8:1::8:800:200c:417a/76")
  #=> false

ip6.include? "2001:db8::8:800:200c:1"
  #=> true
# File lib/ipaddress_2/ipv6.rb, line 618
def include?(oth)
  unless oth.is_a? IPAddress::IPv6
    oth = IPv6.new(oth)
  end
  @prefix <= oth.prefix and network_u128 == self.class.new(oth.address+"/#@prefix").network_u128
end
include_all?(*others) click to toggle source

Checks whether a subnet includes all the given IPv4 objects or strings.

ip = IPAddress("2001:db8:8:800::1/64")

addr1 = IPAddress("2001:db8:8:800::2/64")
addr2 = IPAddress("2001:db8:8:800::8/64")

ip.include_all?(addr1,addr2)
  #=> true

ip.include_all?("2001:db8:8:800::2/64", "2001:db8:8:800::8/64")
  #=> true
# File lib/ipaddress_2/ipv6.rb, line 640
def include_all?(*others)
  others.all? {|oth| include?(oth)}
end
last() click to toggle source

Like its sibling method IPv4#first, this method returns a new IPv4 object with the last host IP address in the range.

Example: given the 192.168.100.0/24 network, the last host IP address is 192.168.100.254

ip = IPAddress("2001:db8:8:800::/64")

ip.last.to_s
  #=> "2001:db8:8:800:ffff:ffff:ffff:ffff"

The object IP doesn't need to be a network: the method automatically gets the network number from it

ip = IPAddress("2001:db8:9:800::2/64")

ip.last.to_s
  #=> "2001:db8:9:800:ffff:ffff:ffff:ffff"
# File lib/ipaddress_2/ipv6.rb, line 298
def last
  if prefix == 128
    return self
  else
    IPAddress::IPv6::parse_u128(broadcast_u128)
  end
end
literal() click to toggle source

Literal version of the IPv6 address

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.literal
  #=> "2001-0db8-0000-0000-0008-0800-200c-417a.ipv6-literal.net"
# File lib/ipaddress_2/ipv6.rb, line 937
def literal
  @address.gsub(":","-") + ".ipv6-literal.net"
end
loopback?() click to toggle source

Returns true if the address is a loopback address

See IPAddress::IPv6::Loopback for more information

# File lib/ipaddress_2/ipv6.rb, line 670
def loopback?
  @prefix == 128 and @compressed == "::1"
end
mapped?() click to toggle source

Returns true if the address is a mapped address

See IPAddress::IPv6::Mapped for more information

# File lib/ipaddress_2/ipv6.rb, line 707
def mapped?
  to_u128 >> 32 == 0xffff
end
network() click to toggle source

Returns a new IPv6 object with the network number for the given IP.

ip = IPAddress "2001:db8:1:1:1:1:1:1/32"

ip.network.to_string
  #=> "2001:db8::/32"
# File lib/ipaddress_2/ipv6.rb, line 950
def network
  self.class.parse_u128(network_u128, @prefix)
end
network?() click to toggle source

True if the IPv6 address is a network

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.network?
  #=> false

ip6 = IPAddress "2001:db8:8:800::/64"

ip6.network?
  #=> true
# File lib/ipaddress_2/ipv6.rb, line 245
def network?
  to_u128 | @prefix.to_u128 == @prefix.to_u128
end
network_u128() click to toggle source

Returns the network number in Unsigned 128bits format

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.network_u128
  #=> 42540766411282592856903984951653826560
# File lib/ipaddress_2/ipv6.rb, line 555
def network_u128
  to_u128 & @prefix.to_u128
end
next()
Alias for: succ
next_network() click to toggle source

Returns the network address of the network succeeding this one.

Example:

ip = IPAddress::IPv6.new("fc42:1337:0:0::/64")
ip.next_network.to_string
  #=> "fc42:1337:0:1::/64"
# File lib/ipaddress_2/ipv6.rb, line 461
def next_network
  advance_network 1
end
pred() click to toggle source

Returns the predecessor to the IP address

Example:

ip6 = IPAddress("2001:db8::8:800:200c:417a/64")

ip6.pred.to_string
  => "2001:db8::8:800:200c:4179/64"
# File lib/ipaddress_2/ipv6.rb, line 854
def pred
  IPAddress::IPv6.parse_u128(to_u128.pred, prefix)
end
prefix() click to toggle source

Returns an instance of the prefix object

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.prefix
  #=> 64
# File lib/ipaddress_2/ipv6.rb, line 154
def prefix
  @prefix
end
prefix=(num) click to toggle source

Set a new prefix number for the object

This is useful if you want to change the prefix to an object created with IPv6::parse_u128 or if the object was created using the default prefix of 128 bits.

ip6 = IPAddress("2001:db8::8:800:200c:417a")

puts ip6.to_string
  #=> "2001:db8::8:800:200c:417a/128"

ip6.prefix = 64
puts ip6.to_string
  #=> "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 175
def prefix=(num)
  @prefix = Prefix128.new(num)
end
previous_network() click to toggle source

Returns the network address of the network preceeding this one.

Example:

ip = IPAddress::IPv6.new("fc42:1337:0:5::/64")
ip.previous_network.to_string
  #=> "fc42:1337:0:4::/64"
# File lib/ipaddress_2/ipv6.rb, line 485
def previous_network
  regress_network 1
end
regress_network(amount) click to toggle source

Returns the network address of the n-th network preceeding this one.

Example:

ip = IPAddress::IPv6.new("fc42:1337:0:5::/64")
ip.regress_network(4).to_string
  #=> "fc42:1337:0:1::/64"
# File lib/ipaddress_2/ipv6.rb, line 473
def regress_network(amount)
  advance_network(-amount)
end
reverse() click to toggle source

Returns the IPv6 address in a DNS reverse lookup string, as per RFC3172 and RFC2874.

ip6 = IPAddress "3ffe:505:2::f"

ip6.reverse
  #=> "f.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.0.0.0.5.0.5.0.e.f.f.3.ip6.arpa"
# File lib/ipaddress_2/ipv6.rb, line 393
def reverse
  to_hex.reverse.gsub(/./){|c| c+"."} + "ip6.arpa"
end
Also aliased as: arpa
size() click to toggle source

Returns the number of IP addresses included in the network. It also counts the network address and the broadcast address.

ip6 = IPAddress("2001:db8::8:800:200c:417a/64")

ip6.size
  #=> 18446744073709551616
# File lib/ipaddress_2/ipv6.rb, line 597
def size
  2 ** @prefix.host_prefix
end
split(subnets=2) click to toggle source

Splits a network into different subnets

NOTE: Will allow you to split past /64 against RFC 5375

If the IP Address is a network, it can be divided into multiple networks. If self is not a network, this method will calculate the network from the IP and then subnet it.

If subnets is an power of two number, the resulting networks will be divided evenly from the supernet.

network = IPAddress("2001:db8:8::/48")

network / 4   # implies map{|i| i.to_string}
  #=> ["2001:db8:8::/50",
  #=>  "2001:db8:8:4000::/50",
  #=>  "2001:db8:8:8000::/50",
  #=>  "2001:db8:8:c000::/50"]

If num is any other number, the supernet will be divided into some networks with a even number of hosts and other networks with the remaining addresses.

network = IPAddress("2001:db8:8::/48")

network / 3   # implies map{|i| i.to_string}

  #=> ["2001:db8:8::/50",
  #=>  "2001:db8:8:4000::/50",
  #=>  "2001:db8:8:8000::/49"]

Returns an array of IPv6 objects

# File lib/ipaddress_2/ipv6.rb, line 535
def split(subnets=2)
  unless (1..(2**@prefix.host_prefix)).include? subnets
    raise ArgumentError, "Value #{subnets} out of range" 
  end
  networks = subnet(newprefix(subnets))
  until networks.size == subnets
    networks = sum_first_found(networks)
  end
  return networks
end
Also aliased as: /
subnet(subprefix) click to toggle source

This method implements the subnetting function similar to the one described in RFC3531.

By specifying a new prefix, the method calculates the network number for the given IPv4 object and calculates the subnets associated to the new prefix.

For example, given the following network:

ip = IPAddress "172.16.10.0/24"

we can calculate the subnets with a /26 prefix

ip.subnet(26).map{&:to_string)
  #=> ["172.16.10.0/26", "172.16.10.64/26",
       "172.16.10.128/26", "172.16.10.192/26"]

The resulting number of subnets will of course always be a power of two.

# File lib/ipaddress_2/ipv6.rb, line 789
def subnet(subprefix)
  unless ((@prefix.to_i)..128).include? subprefix
    raise ArgumentError, "New prefix must be between #@prefix and 128"
  end
  Array.new(2**(subprefix-@prefix.to_i)) do |i|
    self.class.parse_u128(network_u128+(i*(2**(128-subprefix))), subprefix)
  end
end
subtract(oth, validating=true) click to toggle source

Returns a new IPv6 object which is the result of decreasing this IP address by a given value. In other words, this arithmetically subtracts IP addresses.

Will raise an error if the resulting address is in a different subnet, except validating is set to false.

Example:

ip = IPAddress::IPv6.new("fc42:1337::a/64")
ip.subtract(5).to_string
  #=> "fc42:1337::5/64"
# File lib/ipaddress_2/ipv6.rb, line 436
def subtract(oth, validating=true)
  oth = oth.to_i if oth.kind_of? IPAddress::IPv6 # oth shall be integer
  add(-oth, validating)
end
succ() click to toggle source

Returns the successor to the IP address

Example:

ip6 = IPAddress("2001:db8::8:800:200c:417a/64")

ip6.succ.to_string
  => "2001:db8::8:800:200c:417b/64"
# File lib/ipaddress_2/ipv6.rb, line 839
def succ
  IPAddress::IPv6.parse_u128(to_u128.succ, prefix)
end
Also aliased as: next
supernet(new_prefix) click to toggle source

Returns a new IPv4 object from the supernetting of the instance network.

Supernetting is similar to subnetting, except that you getting as a result a network with a smaller prefix (bigger host space). For example, given the network

ip = IPAddress("2001:db8:8:800::1/64")

you can supernet it with a new /32 prefix

ip.supernet(32).to_string
  #=> "2001:db8::/32"

However if you supernet it with a /22 prefix, the network address will change:

ip.supernet(22).to_string
  #=> "2001:c00::/22"

If new_prefix is less than 1, returns 0000:0000:0000:0000:0000:0000:0000:0000/0

# File lib/ipaddress_2/ipv6.rb, line 761
def supernet(new_prefix)
  raise ArgumentError, "New prefix must be smaller than existing prefix" if new_prefix >= @prefix.to_i
  return self.class.new("0000:0000:0000:0000:0000:0000:0000:0000/0") if new_prefix < 1
  return self.class.new(@address+"/#{new_prefix}").network
end
to_hex() click to toggle source

Returns a Base16 number representing the IPv6 address

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.to_hex
  #=> "20010db80000000000080800200c417a"
# File lib/ipaddress_2/ipv6.rb, line 343
def to_hex
  hexs.join("")
end
to_i() click to toggle source

Returns a decimal format (unsigned 128 bit) of the IPv6 address

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.to_i
  #=> 42540766411282592856906245548098208122
# File lib/ipaddress_2/ipv6.rb, line 227
def to_i
  to_hex.hex
end
Also aliased as: to_u128
to_s() click to toggle source

Returns the IPv6 address in a human readable form, using the compressed address.

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.to_s
  #=> "2001:db8::8:800:200c:417a"
# File lib/ipaddress_2/ipv6.rb, line 214
def to_s
  @compressed
end
to_string() click to toggle source

Returns the IPv6 address in a human readable form, using the compressed address.

ip6 = IPAddress "2001:0db8:0000:0000:0008:0800:200c:417a/64"

ip6.to_string
  #=> "2001:db8::8:800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 201
def to_string
  "#@compressed/#@prefix"
end
to_string_uncompressed() click to toggle source

Unlike its counterpart IPv6#to_string method, IPv6#to_string_uncompressed returns the whole IPv6 address and prefix in an uncompressed form

ip6 = IPAddress "2001:db8::8:800:200c:417a/64"

ip6.to_string_uncompressed
  #=> "2001:0db8:0000:0000:0008:0800:200c:417a/64"
# File lib/ipaddress_2/ipv6.rb, line 188
def to_string_uncompressed
  "#@address/#@prefix"
end
to_u128()
Alias for: to_i
unique_local?() click to toggle source

Checks if an IPv6 address objects belongs to a unique-local network RFC4193

Example:

ip = IPAddress "fc00::1"
ip.unique_local?
  #=> true
# File lib/ipaddress_2/ipv6.rb, line 698
def unique_local?
  [self.class.new("fc00::/7")].any? {|i| i.include? self}
end
unspecified?() click to toggle source

Returns true if the address is an unspecified address

See IPAddress::IPv6::Unspecified for more information

# File lib/ipaddress_2/ipv6.rb, line 661
def unspecified?
  @prefix == 128 and @compressed == "::"
end

Private Instance Methods

aggregate(ip1,ip2) click to toggle source
# File lib/ipaddress_2/ipv6.rb, line 1216
def aggregate(ip1,ip2)
  return [ip1] if ip1.include? ip2

  snet = ip1.supernet(ip1.prefix-1)
  if snet.include_all?(ip1, ip2) && ((ip1.size + ip2.size) == snet.size)
    return [snet]
  else
    return [ip1, ip2]
  end
end
compress_address() click to toggle source
# File lib/ipaddress_2/ipv6.rb, line 1201
def compress_address
  str = @groups.map{|i| i.to_s 16}.join ":"
  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,}/, '::')
end
newprefix(num) click to toggle source
# File lib/ipaddress_2/ipv6.rb, line 1185
def newprefix(num)
  return @prefix + (Math::log2(num).ceil )
end
sum_first_found(arr) click to toggle source
# File lib/ipaddress_2/ipv6.rb, line 1189
def sum_first_found(arr)
  dup = arr.dup.reverse
  dup.each_with_index do |obj,i|
    a = [self.class.summarize(obj,dup[i+1])].flatten
    if a.size == 1
      dup[i..i+1] = a
      return dup.reverse
    end
  end
  return dup.reverse
end