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[mirrors/Programs.git] / php / ipv6wildcard.php

diff --git a/php/ipv6wildcard.php b/php/ipv6wildcard.php
old mode 100644 (file)
new mode 100755 (executable)
index 15c3ad5..458b3b3
--- a/php/ipv6wildcard.php
+++ b/php/ipv6wildcard.php
@@ -1,10 +1,15 @@
+#!/usr/bin/php
 <?php
 
 /**
+ * (c) 2020 - Tomas Mudrunka <harvie@github>
+ *
  * Given IPv6 address and prefix creates array of * wildcard suffixed
  * addresses to be used for as reverse DNS records
  */
 function ipv6_prefix2wildcards($address, $prefix) {
+       //Special case of /0 prefix
+       if($prefix == 0) return ['*'];
 
        //Parse ip and prefix
        echo("IPv6 prefix: ".$address."/".$prefix."\n");
@@ -13,9 +18,10 @@ function ipv6_prefix2wildcards($address, $prefix) {
        $a = gmp_import($addr);
 
        //Separate maskable octets
-       $pref_hex = ceil($pref / 4)*4; //Prefix rounded up to full octets
-       $pref_rem = $pref_hex - $pref; //Remainder of prefix
-       echo("Rounding prefix: ".$pref_hex."-".$pref_rem."\n");
+       $pref_hex = ceil($pref / 4); //Number of prefix octets
+       $pref_bin = $pref_hex*4; //Number of prefix octets in bits
+       $pref_rem = $pref_bin - $pref; //Remainder of prefix
+       echo("Rounding prefix: ".$pref_bin."-".$pref_rem."\n");
 
        $a = gmp_div_q($a, gmp_pow(2,128-$prefix)); //Truncate to just prefix
        $a = gmp_mul($a, gmp_pow(2,$pref_rem)); //Fill remaining bits in last wildcard octet with zeros
@@ -25,12 +31,19 @@ function ipv6_prefix2wildcards($address, $prefix) {
        for($i = 0; $i < (2**$pref_rem) ; $i++) {
                //echo("ADDED: ".$i." = ".decbin($i)."\n");
                $ap = gmp_or($a, gmp_init($i));
-               $wildcards[] = $ap;
+               $w = gmp_strval($ap, 16);
+               $w = str_repeat('0', $pref_hex-strlen($w)).$w;
+               if(strlen($w) < 32) $w.='*';
+               $wildcards[] = $w;
        }
 
        return $wildcards;
 }
 
+function ipv6_string2rev($str) {
+       return implode('.',str_split(strrev($str)));
+}
+
 if(isset($argv[2])) {
        $wcs = ipv6_prefix2wildcards($argv[1],$argv[2]);
 } else {
@@ -39,6 +52,10 @@ if(isset($argv[2])) {
 
 echo("\n");
 foreach($wcs as $w) {
-  //echo(gmp_strval($w, 2)."* :-)\n");
-  echo(gmp_strval($w, 16)."*\n");
+       echo($w."\n");
+}
+
+echo("\n");
+foreach($wcs as $w) {
+       echo(ipv6_string2rev($w)."\n");
 }