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tott/ip_in_range.php

Created November 27, 2013 22:46
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  1. tott created this gist Nov 27, 2013.
    18 changes: 18 additions & 0 deletions ip_in_range.php
    View file
    Original file line number Diff line number Diff line change
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    /**
    * Check if a given ip is in a network
    * @param string $ip IP to check in IPV4 format eg. 127.0.0.1
    * @param string $range IP/CIDR netmask eg. 127.0.0.0/24, also 127.0.0.1 is accepted and /32 assumed
    * @return boolean true if the ip is in this range / false if not.
    */
    function ip_in_range( $ip, $range ) {
    if ( strpos( $range, '/' ) == false ) {
    $range .= '/32';
    }
    // $range is in IP/CIDR format eg 127.0.0.1/24
    list( $range, $netmask ) = explode( '/', $range, 2 );
    $range_decimal = ip2long( $range );
    $ip_decimal = ip2long( $ip );
    $wildcard_decimal = pow( 2, ( 32 - $netmask ) ) - 1;
    $netmask_decimal = ~ $wildcard_decimal;
    return ( ( $ip_decimal & $netmask_decimal ) == ( $range_decimal & $netmask_decimal ) );
    }