diff -r 1cc8a038ad20 -r e4bbd6fb8df3 includes/math.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/math.php	Sat Mar 01 18:56:37 2008 -0500
@@ -0,0 +1,308 @@
+<?php
+
+/*
+ * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
+ * Version 1.1.2 (Caoineag alpha 2)
+ * Copyright (C) 2006-2007 Dan Fuhry
+ * diffiehellman.php - Diffie Hellman key exchange and supporting functions
+ *
+ * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.
+ */
+
+/**
+ * EnanoMath GMP backend
+ */
+
+class EnanoMath_GMP
+{
+  var $api = 'GMP';
+  
+  /**
+   * Initializes a number to a GMP integer.
+   * @param string String representation of the number
+   * @param int Base the number is currently in, defaults to 10
+   * @return resource
+   */
+  
+  function init($int, $base = 10)
+  {
+    return ( is_resource($int) ) ? $int : gmp_init($int, $base);
+  }
+  
+  /**
+   * Converts a number from a GMP integer to a string
+   * @param resource
+   * @param int Base, default is 10
+   * @return string
+   */
+  
+  function str($int, $base = 10)
+  {
+    return ( is_string($int) ) ? $int : gmp_strval($int, $base);
+  }
+  
+  /**
+   * Converts a number between bases.
+   * @param resource BigInt to convert
+   * @param int Base to convert from
+   * @param int Base to convert to
+   */
+   
+  function basecon($int, $from, $to)
+  {
+    return $this->init(gmp_strval(gmp_init($this->str($int), $from), $to));
+  }
+  
+  /**
+   * Generates a random integer.
+   * @param int Length
+   * @return resource
+   */
+  
+  function random($len)
+  {
+    return gmp_random($len);
+  }
+  
+  /**
+   * Powmod operation (calculates (a ^ b) mod m)
+   * @param resource a
+   * @param resource b
+   * @param resource m
+   * @return resource
+   */
+  
+  function powmod($a, $b, $m)
+  {
+    $a = $this->init($a);
+    $b = $this->init($b);
+    $m = $this->init($m);
+    return ( function_exists('gmp_powm') ) ? gmp_powm($a, $b, $m) : gmp_mod(gmp_pow($a, $b), $m);
+  }
+}
+
+/**
+ * EnanoMath big_int backend
+ */
+
+class EnanoMath_BigInt
+{
+  var $api = 'big_int';
+  
+  /**
+   * Initializes a number to a BigInt integer.
+   * @param string String representation of the number
+   * @param int Base the number is in, defaults to 10
+   * @return resource
+   */
+  
+  function init($int, $base = 10)
+  {
+    return (is_resource($int)) ? $int : bi_from_str($int, $base);
+  }
+  
+  /**
+   * Converts a number from a BigInt integer to a string
+   * @param resource
+   * @param int Base, default is 10
+   * @return string
+   */
+  
+  function str($int, $base = 10)
+  {
+    return ( is_string($int) ) ? $int : bi_to_str($int, $base);
+  }
+  
+  /**
+   * Generates a random integer
+   * @param int Length (bits)
+   * @return resource
+   */
+  
+  function random($len)
+  {
+    return bi_rand($len);
+  }
+  
+  /**
+   * Converts a number between bases.
+   * @param resource BigInt to convert
+   * @param int Base to convert from
+   * @param int Base to convert to
+   */
+  
+  function basecon($int, $from, $to)
+  {
+    return bi_base_convert($this->str($int, $from), $from, $to);
+  }
+  
+  /**
+   * Powmod operation (calculates (a ^ b) mod m)
+   * @param resource a
+   * @param resource b
+   * @param resource m
+   * @return resource
+   */
+  
+  function powmod($a, $b, $m)
+  {
+    $a = $this->init($a);
+    $b = $this->init($b);
+    $m = $this->init($m);
+    return bi_powmod($a, $b, $m);
+  }
+}
+
+/**
+ * EnanoMath BCMath backend
+ */
+
+class EnanoMath_BCMath
+{
+  var $api = 'BCMath';
+  
+  /**
+   * Initializes a number to a BCMath integer.
+   * @param string String representation of the number
+   * @param int Base the number is in, defaults to 10
+   * @return resource
+   */
+  
+  function init($int, $base = 10)
+  {
+    return $this->basecon($int, $base, 10);
+  }
+  
+  /**
+   * Converts a number from a BCMath integer to a string
+   * @param resource
+   * @param int Base, default is 10
+   * @return string
+   */
+   
+  function str($res)
+  {
+    return ( is_string($res) ) ? $res : strval($this->basecon($res, 10, $base));
+  }
+  
+  /**
+   * Generates a random integer
+   * @param int Length in bits
+   * @return resource
+   */
+  
+  function random($len)
+  {
+    $len = 4 * $len;
+    $chars = '0123456789abcdef';
+    $ret = '';
+    for ( $i = 0; $i < $len; $i++ )
+    {
+      $chid = mt_rand ( 0, strlen($chars) - 1 );
+      $chr = $chars{$chid};
+      $ret .= $chr;
+    }
+    return $this->basecon($this->init($ret), 16, 10);
+  }
+  
+  /**
+   * Converts a number between bases.
+   * @param resource BigInt to convert
+   * @param int Base to convert from
+   * @param int Base to convert to
+   */
+  
+  function basecon($int, $from, $to)
+  {
+    if ( $from != 10 )
+      $int = $this->_bcmath_base2dec($int, $from);
+    if ( $to != 10 )
+      $int = $this->_bcmath_dec2base($int, $to);
+    return $int;
+  }
+  
+  /**
+   * Powmod operation (calculates (a ^ b) mod m)
+   * @param resource a
+   * @param resource b
+   * @param resource m
+   * @return resource
+   */
+  
+  function powmod($a, $b, $m)
+  {
+    $a = $this->init($a);
+    $b = $this->init($b);
+    $m = $this->init($m);
+    return ( function_exists('bcpowmod') ) ? bcpowmod($a, $b, $m) : bcmod( bcpow($a, $b), $m );
+  }
+  
+  // from us.php.net/bc:
+  // convert a decimal value to any other base value
+  function _bcmath_dec2base($dec,$base,$digits=FALSE) {
+      if($base<2 or $base>256) die("Invalid Base: ".$base);
+      bcscale(0);
+      $value="";
+      if(!$digits) $digits=$this->_bcmath_digits($base);
+      while($dec>$base-1) {
+          $rest=bcmod($dec,$base);
+          $dec=bcdiv($dec,$base);
+          $value=$digits[$rest].$value;
+      }
+      $value=$digits[intval($dec)].$value;
+      return (string) $value;
+  }
+  
+  // convert another base value to its decimal value
+  function _bcmath_base2dec($value,$base,$digits=FALSE) {
+      if($base<2 or $base>256) die("Invalid Base: ".$base);
+      bcscale(0);
+      if($base<37) $value=strtolower($value);
+      if(!$digits) $digits=$this->_bcmath_digits($base);
+      $size=strlen($value);
+      $dec="0";
+      for($loop=0;$loop<$size;$loop++) {
+          $element=strpos($digits,$value[$loop]);
+          $power=bcpow($base,$size-$loop-1);
+          $dec=bcadd($dec,bcmul($element,$power));
+      }
+      return (string) $dec;
+  }
+  
+  function _bcmath_digits($base) {
+      if($base>64) {
+          $digits="";
+          for($loop=0;$loop<256;$loop++) {
+              $digits.=chr($loop);
+          }
+      } else {
+          $digits ="0123456789abcdefghijklmnopqrstuvwxyz";
+          $digits.="ABCDEFGHIJKLMNOPQRSTUVWXYZ-_";
+      }
+      $digits=substr($digits,0,$base);
+      return (string) $digits;
+  }
+}
+
+/**
+ * Creates a new math object based on what libraries are available.
+ * @return object
+ */
+
+function enanomath_create()
+{
+  if ( function_exists('gmp_init') )
+    return new EnanoMath_GMP();
+  else if ( function_exists('bi_from_str') )
+    return new EnanoMath_BigInt();
+  else if ( function_exists('bcadd') )
+    return new EnanoMath_BCMath();
+  else
+    throw new Exception('dh_err_not_supported');
+}
+
+?>