InetCidr

Classless Inter-Domain Routing (CIDR) library for Elixir that is compatible with Erlang's :inet and supports both IPv4 and IPv6.

Install

Add :inet_cidr to your list of dependencies in mix.exs:

defp deps do
  [
    {:inet_cidr, "~> 1.0.0"}
  ]
end

Usage

Parsing a CIDR string (IPv4 or IPv6)

iex> InetCidr.parse_cidr("192.168.0.0/16")
{:ok, {{192,168,0,0}, {192,168,255,255}, 16}}

iex> InetCidr.parse_cidr!("192.168.0.0/16")
{{192,168,0,0}, {192,168,255,255}, 16}

iex> InetCidr.parse_cidr("2001:abcd::/32")
{:ok, {{8193, 43981, 0, 0, 0, 0, 0, 0}, {8193, 43981, 65535, 65535, 65535, 65535, 65535, 65535}, 32}}

iex> InetCidr.parse_cidr!("2001:abcd::/32")
{{8193, 43981, 0, 0, 0, 0, 0, 0}, {8193, 43981, 65535, 65535, 65535, 65535, 65535, 65535}, 32}

Printing a CIDR block to string

iex> "192.168.0.0/16" |> InetCidr.parse_cidr! |> InetCidr.to_string
"192.168.0.0/16"

iex> "2001:abcd::/32" |> InetCidr.parse_cidr! |> InetCidr.to_string
"2001:ABCD::/32"

Check whether a CIDR block contains an IP address

There are also parse_cidr/1 and parse_address/1 versions that return {:ok,_cidr} and {:error,_msg} tuples.

IPv4

iex> cidr = InetCidr.parse_cidr!("192.168.0.0/16")
{{192,168,0,0}, {192,168,255,255}, 16}

iex> address1 = InetCidr.parse_address!("192.168.15.20")
{192,168,15,20}

iex> InetCidr.contains?(cidr, address1)
true

iex> address2 = InetCidr.parse_address!("10.168.15.20")
{10,168,15,20}

iex> InetCidr.contains?(cidr, address2)
false

IPv6

iex> cidr = InetCidr.parse_cidr!("2001:abcd::/32")
{{8193, 43981, 0, 0, 0, 0, 0, 0}, {8193, 43981, 65535, 65535, 65535, 65535, 65535, 65535}, 32}

iex> address1 = InetCidr.parse_address!("2001:abcd::")
{8193, 43981, 0, 0, 0, 0, 0, 0}

iex> InetCidr.contains?(cidr, address1)
true

iex> address2 = InetCidr.parse_address!("abcd:2001::")
{43981, 8193, 0, 0, 0, 0, 0, 0}

iex> InetCidr.contains?(cidr, address2)
false

Get the end of a CIDR block

iex> InetCidr.calc_end_address({192, 168, 0, 0}, 16)
{:ok, {192, 168, 255, 255}}

iex> InetCidr.calc_end_address!({192, 168, 0, 0}, 16)
{192, 168, 255, 255}

License

Copyright (c) 2015-2024 Cobenian and Bryan Weber

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.