IPv4 and IPv6 regexp by jteeuven & Chetan Hanumantha

ipv4_and_ipv6_regexp.rb

      # IP v4 and v6 (with compression) validation regexp
      # http://regexlib.com/REDetails.aspx?regexp_id=1000
      # http://regexlib.com/REDetails.aspx?regexp_id=2685

      VALID_IP = %r{
          (^(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[0-9]{1,2})(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[0-9]{1,2})){3}$)                                                         | # ip v4
          (^(
           (([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4})                                                                                                                   | # ip v6 not abbreviated
           (([0-9A-Fa-f]{1,4}:){6}:[0-9A-Fa-f]{1,4})                                                                                                                  | # ip v6 with double colon in the end
           (([0-9A-Fa-f]{1,4}:){5}:([0-9A-Fa-f]{1,4}:)?[0-9A-Fa-f]{1,4})                                                                                              | # - ip addresses v6
           (([0-9A-Fa-f]{1,4}:){4}:([0-9A-Fa-f]{1,4}:){0,2}[0-9A-Fa-f]{1,4})                                                                                          | # - with
           (([0-9A-Fa-f]{1,4}:){3}:([0-9A-Fa-f]{1,4}:){0,3}[0-9A-Fa-f]{1,4})                                                                                          | # - double colon
           (([0-9A-Fa-f]{1,4}:){2}:([0-9A-Fa-f]{1,4}:){0,4}[0-9A-Fa-f]{1,4})                                                                                          | # - in the middle
           (([0-9A-Fa-f]{1,4}:){6} ((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3} (\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))                            | # ip v6 with compatible to v4
           (([0-9A-Fa-f]{1,4}:){1,5}:((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))                           | # ip v6 with compatible to v4
           (([0-9A-Fa-f]{1,4}:){1}:([0-9A-Fa-f]{1,4}:){0,4}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))     | # ip v6 with compatible to v4
           (([0-9A-Fa-f]{1,4}:){0,2}:([0-9A-Fa-f]{1,4}:){0,3}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))   | # ip v6 with compatible to v4
           (([0-9A-Fa-f]{1,4}:){0,3}:([0-9A-Fa-f]{1,4}:){0,2}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))   | # ip v6 with compatible to v4
           (([0-9A-Fa-f]{1,4}:){0,4}:([0-9A-Fa-f]{1,4}:){1}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))     | # ip v6 with compatible to v4
           (::([0-9A-Fa-f]{1,4}:){0,5}((\b((25[0-5])|(1\d{2})|(2[0-4]\d) |(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))                         | # ip v6 with compatible to v4
           ([0-9A-Fa-f]{1,4}::([0-9A-Fa-f]{1,4}:){0,5}[0-9A-Fa-f]{1,4})                                                                                               | # ip v6 with compatible to v4
           (::([0-9A-Fa-f]{1,4}:){0,6}[0-9A-Fa-f]{1,4})                                                                                                               | # ip v6 with double colon at the begining
           (([0-9A-Fa-f]{1,4}:){1,7}:)                                                                                                                                  # ip v6 without ending
          )$)
        }x