Local IP Checker

Simple ruby gem that provides checking if given URL resolves to local IPv4/IPv6 address.

Abstract

If your system makes HTTP requests to an URL provided by 3rd-party it's important to check if this URL resolves to some kind of local IP address. This gem performs checks against the following types of local IP addresses:

1. IPv4 and IPv6 localhost addresses.
2. IPv4 0.0.0.0 and IPv6 :: addresses.
3. IPv4 private address ranges (e. g. 10.0.0.0/8).
4. IPv6 unique local addresses (fc00::/7).
5. IPv6 site-local address (fec0::/10)
6. IPv4 and IPv6 link-local addresses.

Usage

Example:

require "local_ip_checker"

LocalIPChecker.local?("google.com") # => false
LocalIPChecker.nonlocal?("google.com") => true
LocalIPChecker.local?("localhost") => true
LocalIPChecker.local?("::") # => true