class NetAddr::EUI

EUI - Extended Unique Identifier

A class & series of methods for creating and manipulating Extended Unique Identifier (EUI) addresses. Two types of address formats are supported EUI-48 and EUI-64. The most common use for this class will be to manipulate MAC addresses (which are essentially a type of EUI-48 address).

EUI addresses are separated into two parts, the Organizationally Unique Identifier (OUI) and the Extended Identifier (EI). The OUI is assigned by the IEEE and is used to identify a particular hardware manufacturer. The EI is assigned by the hardware manufacturer as a per device unique address.

Probably the most useful feature of this class, and thus the reason it was created, is to help automate certain address assignments within IP. For example, IPv6 Link Local addresses use MAC addresses for IP auto-assignment and multicast MAC addresses are determined based on the multicast IP address.

Public Class Methods

create(eui) click to toggle source

Synopsis

Create a new EUI48 or EUI64 object.

Example:
addr = NetAddr::EUI.create('aa-bb-cc-dd-ee-ff')
addr = NetAddr::EUI.create('aa:bb:cc:dd:ee:ff')
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr = NetAddr::EUI.create('aa-bb-cc-dd-ee-ff-00-01')

Arguments

  • eui = EUI as a String

Returns

# File lib/eui.rb, line 93
def EUI.create(eui)
    if (!eui.kind_of? String)
        raise ArgumentError, "Expected String, but #{eui.class} provided."
    end

    # validate
    NetAddr.validate_eui(eui)

    # remove formatting characters
    eui.gsub!(/[\.\:\-]/, '')

    if (eui.length == 12)
        eui = NetAddr::EUI48.new(eui)
    else
        eui = NetAddr::EUI64.new(eui)
    end

    return(eui)
end
new(eui) click to toggle source

Synopsis

This method performs absolutely no error checking, and is meant to be used only by
other internal methods for the sake of the speedier creation of EUI objects.
Please consider using #create unless you know what you are doing with 100% certainty.

Example:
NetAddr::EUI48.new('aabbccddeeff')

Arguments:

  • EUI as a String or Integer. Strings should contain no formatting characters.

# File lib/eui.rb, line 45
def initialize(eui)

    if (eui.kind_of?(Integer))
        @eui_i = eui
        @eui = eui.to_s(16)
        if ( self.kind_of?(NetAddr::EUI48) )
            @eui = '0' * (12 - @eui.length) << @eui if (@eui.length < 12)
        else
            @eui = '0' * (16 - @eui.length) << @eui if (@eui.length < 16)
        end

    elsif(eui.kind_of?(String))
        @eui = eui
        @eui_i = eui.to_i(16)
    else
        raise ArgumentError, "Expected String or Integer, but #{eui.class} provided."
    end

    # set ei & oui
    if ( self.kind_of?(NetAddr::EUI48) )
        @ei = @eui.slice(6..11)
    else
        @ei = @eui.slice(6..15)
    end

    @oui = @eui.slice(0..5)

end

Public Instance Methods

address(options=nil) click to toggle source

Synopsis

Returns EUI address. The default address format is xxxx.xxxx.xxxx

Example:
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr.address(:Delimiter => '-') => "aa-bb-cc-dd-ee-ff"
addr.address(:Delimiter => ':') => "aa:bb:cc:dd:ee:ff"

Arguments:

  • options = Hash with the following fields:

    :Delimiter -- delimitation character. valid values are (- : .)

Returns:

  • String

# File lib/eui.rb, line 132
def address(options=nil)
    known_args = [:Delimiter]
    delimiter = '-'

    if (options)
        if (!options.kind_of? Hash)
            raise ArgumentError, "Expected Hash, but #{options.class} provided."
        end
        NetAddr.validate_args(options.keys,known_args)

        if (options.has_key?(:Delimiter))
            delimiter = options[:Delimiter]
            delimiter = '-' if (delimiter != ':' && delimiter != '.')
        end
    end

    if (delimiter == '-' || delimiter == ':')
        addr = octets.join(delimiter)
    elsif (delimiter == '.')
            toggle = 0
            octets.each do |x|
                if (!addr)
                    addr = x
                    toggle = 1
                elsif (toggle == 0)
                    addr = addr  << '.' << x
                    toggle = 1
                else
                    addr = addr << x
                    toggle = 0
                end
            end
    end

    return(addr)
end
ei(options=nil) click to toggle source

Synopsis

Returns Extended Identifier portion of an EUI address (the vendor assigned ID). The default address format is xx-xx-xx

Example:
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr.ei(:Delimiter => '-') => "dd-ee-ff"

Arguments:

  • options = Hash with the following fields:

    :Delimiter -- delimitation character. valid values are (-, and :)

Returns:

  • String

# File lib/eui.rb, line 188
def ei(options=nil)
    known_args = [:Delimiter]
    delimiter = '-'

    if (options)
        if (!options.kind_of? Hash)
            raise ArgumentError, "Expected Hash, but #{options.class} provided."
        end
        NetAddr.validate_args(options.keys,known_args)

        if (options.has_key?(:Delimiter))
            if (options[:Delimiter] == ':')
                delimiter = options[:Delimiter]
            end
        end
    end

    if ( self.kind_of?(NetAddr::EUI48) )
        ei = octets[3..5].join(delimiter)
    else
        ei = octets[3..7].join(delimiter)
    end

    return(ei)
end
oui(options=nil) click to toggle source

Synopsis

Returns Organizationally Unique Identifier portion of an EUI address (the vendor ID). The default address format is xx-xx-xx.

Example:
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr.oui(:Delimiter => '-') => "aa-bb-cc"

Arguments:

  • options = Hash with the following fields:

    :Delimiter -- delimitation character. valid values are (-, and :)

Returns:

  • String

# File lib/eui.rb, line 256
def oui(options=nil)
    known_args = [:Delimiter]
    delimiter = '-'

    if (options)
        if (!options.kind_of? Hash)
            raise ArgumentError, "Expected Hash, but #{options.class} provided."
        end
        NetAddr.validate_args(options.keys,known_args)

        if (options.has_key?(:Delimiter))
            if (options[:Delimiter] == ':')
                delimiter = options[:Delimiter]
            end
        end
    end
    oui = octets[0..2].join(delimiter)

    return(oui)
end
to_i() click to toggle source

Synopsis

Returns the EUI as an Integer.

Example:
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr.to_i => 187723572702975

Arguments:

  • none

Returns:

  • Integer

# File lib/eui.rb, line 294
def to_i()
    return(@eui_i)
end
to_ipv6(cidr, options=nil) click to toggle source

Synopsis

Given a valid IPv6 subnet, return an IPv6 address based on the current EUI.

Example:
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr.to_ipv6('3ffe::/64') => "3ffe:0000:0000:0000:a8bb:ccff:fedd:eeff"

Arguments:

  • options = Hash with the following fields:

    :Short -- if true, return IPv6 addresses in short-hand notation
    :Objectify -- if true, return CIDR objects

Returns:

# File lib/eui.rb, line 317
def to_ipv6(cidr, options=nil)
    known_args = [:Short, :Objectify]
    objectify = false
    short = false

    if ( !cidr.kind_of?(NetAddr::CIDR) )
        begin
            cidr = NetAddr::CIDR.create(cidr)
        rescue Exception => error
            raise ArgumentError, "CIDR raised the following errors: #{error}"
        end
    elsif (cidr.kind_of?(NetAddr::CIDRv4)  )
        raise ArgumentError, "Expected CIDRv6, but #{cidr.class} provided."
    end

    if (cidr.bits > 64)
        raise ValidationError, "Prefix length of provided CIDR must be /64 or less but was #{cidr.netmask}."
    end

    if (options)
        if (!options.kind_of? Hash)
            raise ArgumentError, "Expected Hash, but #{options.class} provided."
        end
        NetAddr.validate_args(options.keys,known_args)

        if (options.has_key?(:Objectify) && options[:Objectify] == true)
            objectify = true
        end

        if (options.has_key?(:Short) && options[:Short] == true)
            short = true
        end
    end

    # get integer equiv of addr. conver eui48 to eui64 if needed
    if ( self.kind_of?(NetAddr::EUI48) )
        eui_i = self.to_eui64.to_i
    else
        eui_i = self.to_i
    end
  
    # toggle u/l bit
    eui_i = eui_i ^ 0x0200000000000000

    # create ipv6 address
    ipv6 = cidr.to_i | eui_i

    if (!objectify)
        ipv6 = NetAddr.i_to_ip(ipv6, :Version => 6)
        ipv6 = NetAddr.shorten(ipv6) if (short)
    else
        ipv6 = NetAddr::CIDRv6.new(ipv6)
    end

    return(ipv6)
end
to_s() click to toggle source

Synopsis

Returns the EUI as an unformatted String.

Example:
addr = NetAddr::EUI.create('aabb.ccdd.eeff')
addr.to_s => "aabbccddeeff"

Arguments:

  • none

Returns:

  • String

# File lib/eui.rb, line 391
def to_s()
    return(@eui)
end

Private Instance Methods

octets() click to toggle source

Returns array with each element representing a single octet of the eui.

# File lib/eui.rb, line 403
def octets()
    return(@octets) if (@octets)

    @octets = []
    str = ''
    @eui.each_byte do |chr|
        str = str << chr
        if (str.length == 2)
            @octets.push(str)
            str = ''
        end
    end

    return(@octets)
end