How Can i use the key file Generated by RSACryptoServiceProvider to encrypt with php?

Question

I need to be able to encrypt data in PHP using a public key generate by .NET(RSACryptoServiceProvider).  I will then decrypt the data later in C# using the private key.
Code Snippet
<RSAKeyValue><Modulus>xU5JyaPNDKXI/h/uo5Vk89wZSz3zsB1+c+1IMYIQa+mCmuRCRPuoBI7ODSV2ndP6grfhdrWEzhpZtkI3SThbBh/3t+tfZ2PF8Iyv9ECN07V64nPCiJGhAnfENE+J9UD9Kw5czXHgZcBbpM5N0VfXmLSleaS65DDoNPtoStVy7ss=</Modulus><Exponent>AQAB</Exponent><P>4ScAjVrPZii/6lICAP2yDQiNEmNL74+5AcxNVDI0IombfDPIygrqEWmuDu0pngApQak7XnEnLbaDChILFiHPZQ==</P><Q>4FaYlse+cjrlPD/jk+GsTJeuP7yuQx8ztjVnQWVh6GKQP+uk1dAl6kcZOfLNR6LWwE3CSygt8PthTEw96Zbabw==</Q><DP>XvXtNLE9UjATqYeHEtXtV7Pok/3PVC3A8PIzFzTJaluxeXP51sU9rbRt1hvO9rXIsMnooU+GH7Cfmgq8JEyERQ==</DP><DQ>HXkC/vwq9xLpvuqd2XXSjxV2XQVK16Knxo5pjFvnawJX9S3eMADymj7Q/534firUj9snZXxX3MsJ015I3AFnnQ==</DQ><InverseQ>AM0fVCE3n2FKf2zb3CcDEge1Ko35VvMEL+LXgR87QwO2HScZSuLevGLi2SSAkB1vu8RSNzB028SZReeOZWnq4Q==</InverseQ><D>fI+GKdRNOTTYhQZnw8Im74T+OvArjf2wvUMJlqfD8jyDBYIhDCfL1MTK9KW4Er+moSuxHR5Pb0ZXaKa4/HKlk0aJ1jB2C+jg7zTSuPRNuS16BpVHaJYsQurCwZwElXMum+GxeXK/h3wXWq5HwebjqZr0aLUMZKRcweDPRoVFiRE=</D></RSAKeyValue>
As you see this code snippet is a xml format private key. at .net platform,which can use encrypt or dencrypt.
i have try the Extension Crypt RSA ( http://pear.php.net/reference/Crypt_RSA-1.0.0/elementindex_Crypt_RSA.html ) to help me encrypt data by php.but it haven't return a currect result. the data encrypted by php cann't dencrypt by c#.
does the RSA algorithm provider by Crypt_RSA can give a stand result as c#?
BTW :i just use the xmlkeystring like this.
Code Snippet
<?php
require_once("Crypt/RSA.php");
require_once("includes/Utils.class.php");
    $public_key_string = simplexml_load_string("<RSAKeyValue><Modulus>xU5JyaPNDKXI/h/uo5Vk89wZSz3zsB1+c+1IMYIQa+mCmuRCRPuoBI7ODSV2ndP6grfhdrWEzhpZtkI3SThbBh/3t+tfZ2PF8Iyv9ECN07V64nPCiJGhAnfENE+J9UD9Kw5czXHgZcBbpM5N0VfXmLSleaS65DDoNPtoStVy7ss=</Modulus><Exponent>AQAB</Exponent><P>4ScAjVrPZii/6lICAP2yDQiNEmNL74+5AcxNVDI0IombfDPIygrqEWmuDu0pngApQak7XnEnLbaDChILFiHPZQ==</P><Q>4FaYlse+cjrlPD/jk+GsTJeuP7yuQx8ztjVnQWVh6GKQP+uk1dAl6kcZOfLNR6LWwE3CSygt8PthTEw96Zbabw==</Q><DP>XvXtNLE9UjATqYeHEtXtV7Pok/3PVC3A8PIzFzTJaluxeXP51sU9rbRt1hvO9rXIsMnooU+GH7Cfmgq8JEyERQ==</DP><DQ>HXkC/vwq9xLpvuqd2XXSjxV2XQVK16Knxo5pjFvnawJX9S3eMADymj7Q/534firUj9snZXxX3MsJ015I3AFnnQ==</DQ><InverseQ>AM0fVCE3n2FKf2zb3CcDEge1Ko35VvMEL+LXgR87QwO2HScZSuLevGLi2SSAkB1vu8RSNzB028SZReeOZWnq4Q==</InverseQ><D>fI+GKdRNOTTYhQZnw8Im74T+OvArjf2wvUMJlqfD8jyDBYIhDCfL1MTK9KW4Er+moSuxHR5Pb0ZXaKa4/HKlk0aJ1jB2C+jg7zTSuPRNuS16BpVHaJYsQurCwZwElXMum+GxeXK/h3wXWq5HwebjqZr0aLUMZKRcweDPRoVFiRE=</D></RSAKeyValue>");
    $key =new Crypt_RSA_Key(base64_decode($public_key_string->Modulus),base64_decode($public_key_string->Exponent),"public");
    echo "<pre>";
    print_r($key);
    echo "</pre>";
    $rsa_obj = new Crypt_RSA();
    //try encrypt data
    echo "encrypted result is:<br/>".$rsa_obj->encrypt("this is a smple text.",$key)
    ?>
but the encrypted data cann't decrypt by c#?where is the problem?what should i do with php codes?

Answer 1

thank you for your reply, i also found this article by google.but this does not meet scene,  thank you all the same.
i have already solved the problem now,i'd like to post the Solution .infact it's so easy to use rsakey file generated by .net .
-------------rsa.class.php-------------------
Code Snippet
<?php
 * Some constants
define("BCCOMP_LARGER", 1);
class RSA
  * PHP implementation of the RSA algorithm
  * (C) Copyright 2004 Edsko de Vries, Ireland
  * Licensed under the GNU Public License (GPL)
  * This implementation has been verified against [3]
  * (tested Java/PHP interoperability).
  * References:
  * [1] "Applied Cryptography", Bruce Schneier, John Wiley & Sons, 1996
  * [2] "Prime Number Hide-and-Seek", Brian Raiter, Muppetlabs (online)
  * [3] "The Bouncy Castle Crypto Package", Legion of the Bouncy Castle,
  *      (open source cryptography library for Java, online)
  * [4] "PKCS #1: RSA Encryption Standard", RSA Laboratories Technical Note,
  *      version 1.5, revised November 1, 1993
  * Functions that are meant to be used by the user of this PHP module.
  * Notes:
  * - $key and $modulus should be numbers in (decimal) string format
  * - $message is expected to be binary data
  * - $keylength should be a multiple of 8, and should be in bits
  * - For rsa_encrypt/rsa_sign, the length of $message should not exceed
  *   ($keylength / 8) - 11 (as mandated by [4]).
  * - rsa_encrypt and rsa_sign will automatically add padding to the message.
  *   For rsa_encrypt, this padding will consist of random values; for rsa_sign,
  *   padding will consist of the appropriate number of 0xFF values (see [4])
  * - rsa_decrypt and rsa_verify will automatically remove message padding.
  * - Blocks for decoding (rsa_decrypt, rsa_verify) should be exactly
  *   ($keylength / 8) bytes long.
  * - rsa_encrypt and rsa_verify expect a public key; rsa_decrypt and rsa_sign
  *   expect a private key.
  * rsa encrypt data
  * @param binary string $message
  * @param unknown_type $public_key
  * @param numbers $modulus
  * @param numbers $keylength
  * @return binary data
 function rsa_encrypt($message, $public_key, $modulus, $keylength)
  $padded = RSA::add_PKCS1_padding($message, true, $keylength / 8);
  $number = RSA::binary_to_number($padded);
  $encrypted = RSA::pow_mod($number, $public_key, $modulus);
  $result = RSA::number_to_binary($encrypted, $keylength / 8);
  return $result;
 function rsa_decrypt($message, $private_key, $modulus, $keylength)
  $number = RSA::binary_to_number($message);
  $decrypted = RSA::pow_mod($number, $private_key, $modulus);
  $result = RSA::number_to_binary($decrypted, $keylength / 8);
  return RSA::remove_PKCS1_padding($result, $keylength / 8);
 function rsa_sign($message, $private_key, $modulus, $keylength)
  $padded = RSA::add_PKCS1_padding($message, false, $keylength / 8);
  $number = RSA::binary_to_number($padded);
  $signed = RSA::pow_mod($number, $private_key, $modulus);
  $result = RSA::number_to_binary($signed, $keylength / 8);
  return $result;
 function rsa_verify($message, $public_key, $modulus, $keylength)
  return RSA::rsa_decrypt($message, $public_key, $modulus, $keylength);
 function rsa_kyp_verify($message, $public_key, $modulus, $keylength)
  $number = RSA::binary_to_number($message);
  $decrypted = RSA::pow_mod($number, $public_key, $modulus);
  $result = RSA::number_to_binary($decrypted, $keylength / 8);
  return RSA::remove_KYP_padding($result, $keylength / 8);
  * The actual implementation.
  * Requires BCMath support in PHP (compile with --enable-bcmath)
 // Calculate (p ^ q) mod r
 // We need some trickery to [2]:
 //   (a) Avoid calculating (p ^ q) before (p ^ q) mod r, because for typical RSA
 //       applications, (p ^ q) is going to be _WAY_ too large.
 //       (I mean, __WAY__ too large - won't fit in your computer's memory.)
 //   (b) Still be reasonably efficient.
 // We assume p, q and r are all positive, and that r is non-zero.
 // Note that the more simple algorithm of multiplying $p by itself $q times, and
 // applying "mod $r" at every step is also valid, but is O($q), whereas this
 // algorithm is O(log $q). Big difference.
 // As far as I can see, the algorithm I use is optimal; there is no redundancy
 // in the calculation of the partial results.
 function pow_mod($p, $q, $r)
  // Extract powers of 2 from $q
  $factors = array();
  $div = $q;
  $power_of_two = 0;
  while(bccomp($div, "0") == BCCOMP_LARGER)
   $rem = bcmod($div, 2);
   $div = bcdiv($div, 2);
   if($rem) array_push($factors, $power_of_two);
   $power_of_two++;
  // Calculate partial results for each factor, using each partial result as a
  // starting point for the next. This depends of the factors of two being
  // generated in increasing order.
  $partial_results = array();
  $part_res = $p;
  $idx = 0;
  foreach($factors as $factor)
   while($idx < $factor)
    $part_res = bcpow($part_res, "2");
    $part_res = bcmod($part_res, $r);
    $idx++;
   array_push($partial_results, $part_res);
  // Calculate final result
  $result = "1";
  foreach($partial_results as $part_res)
   $result = bcmul($result, $part_res);
   $result = bcmod($result, $r);
  return $result;
 // Function to add padding to a decrypted string
 // We need to know if this is a private or a public key operation [4]
 function add_PKCS1_padding($data, $isPublicKey, $blocksize)
  $pad_length = $blocksize - 3 - strlen($data);
  if($isPublicKey)
   $block_type = "\x02";
   $padding = "";
   for($i = 0; $i < $pad_length; $i++)
    $rnd = mt_rand(1, 255);
    $padding .= chr($rnd);
  else
   $block_type = "\x01";
   $padding = str_repeat("\xFF", $pad_length);
  return "\x00" . $block_type . $padding . "\x00" . $data;
 // Remove padding from a decrypted string
 // See [4] for more details.
 function remove_PKCS1_padding($data, $blocksize)
  assert(strlen($data) == $blocksize);
  $data = substr($data, 1);
  // We cannot deal with block type 0
  if($data{0} == '\0')
  die("Block type 0 not implemented.");
  // Then the block type must be 1 or 2
  assert(($data{0} == "\x01") || ($data{0} == "\x02"));
  // Remove the padding
  $offset = strpos($data, "\0", 1);
  return substr($data, $offset + 1);
 // Remove "kyp" padding
 // (Non standard)
 function remove_KYP_padding($data, $blocksize)
  assert(strlen($data) == $blocksize);
  $offset = strpos($data, "\0");
  return substr($data, 0, $offset);
 // Convert binary data to a decimal number
 function binary_to_number($data)
  $base = "256";
  $radix = "1";
  $result = "0";
  for($i = strlen($data) - 1; $i >= 0; $i--)
   $digit = ord($data{$i});
   $part_res = bcmul($digit, $radix);
   $result = bcadd($result, $part_res);
   $radix = bcmul($radix, $base);
  return $result;
 // Convert a number back into binary form
 function number_to_binary($number, $blocksize)
  $base = "256";
  $result = "";
  $div = $number;
  while($div > 0)
   $mod = bcmod($div, $base);
   $div = bcdiv($div, $base);
   $result = chr($mod) . $result;
  return str_pad($result, $blocksize, "\x00", STR_PAD_LEFT);
?>
-------------RSAProcessor.class.php------------------------
Code Snippet
<?php
require_once("rsa.class.php");
class RSAProcessor
 private $public_key = null;
 private $private_key = null;
 private $modulus = null;
 private $key_length = "1024";
 public function __construct($xmlRsakey=null,$type=null)
         $xmlObj = null;
   if($xmlRsakey==null)
           $xmlObj = simplexml_load_file("xmlfile/RSAKey.xml");
          elseif($type==RSAKeyType::XMLFile)
           $xmlObj = simplexml_load_file($xmlRsakey);
          else
           $xmlObj = simplexml_load_string($xmlRsakey);
         $this->modulus = RSA::binary_to_number(base64_decode($xmlObj->Modulus));
   $this->public_key = RSA::binary_to_number(base64_decode($xmlObj->Exponent));
   $this->key_length = strlen(base64_decode($xmlObj->Modulus))*8;
  * get public key
  * @return string public key
 public function getPublicKey()
  //return base64_encode(RSA::number_to_binary($this->public_key,($this->key_length)/8));
  return $this->public_key;
 public function getPrivateKey()
  //return base64_encode(RSA::number_to_binary($this->private_key,($this->key_length)/8));
  return $this->private_key;
 public function getKeyLength()
  return $this->key_length;
 public function getModulus()
  return $this->modulus;
  * encrypt data
  * @param string $data
  * @return base64 encoded  binary string
 public function encrypt($data)
  return base64_encode(RSA::rsa_encrypt($data,$this->public_key,$this->modulus,$this->key_length));
 public function dencrypt($data)
  return RSA::rsa_decrypt($data,$this->private_key,$this->modulus,$this->key_length);
 public function sign($data)
  return RSA::rsa_sign($data,$this->private_key,$this->modulus,$this->key_length);
 public function verify($data)
  return RSA::rsa_verify($data,$this->public_key,$this->modulus,$this->key_length);
class RSAKeyType
 const XMLFile = 0;
 const XMLString = 1;
?>
-------------- encrypt data with public key-----------------
Code Snippet
<?php
require_once("RSAProcessor.class.php");
$processor = new RSAProcessor
("<RSAKeyValue><Modulus>m6ljoeWhmnd0oRnsVEH5iNw3B8+vKVu7v7CVfMyf6bnKEzHa62TRmT/baJiSevoI/vgm2ph/s1JrQQTaGiErHicigwSC
Aw7+i05WFbnz7tOyiiJJVMfsdd+v7Xan9Hiud05FzxoMbM8vpiMHPEIDbGJ1MiXyupTVkz2WcMHyBoJ4S189opktZ43pviUhy0PeuWkyoU7zR54akPmK
Yg+z5Zr1r7K8lUZ1a3TThfJGxTQR/uZMtZz/q8QF0AANVQ/eyahTv9icBzBoDuncS0Y5l3vqogW1C/ltJvhJpvSn/OgjbRjuixCAptOUmRd13sDWU95/
x0bMq+Lg68lj2OjJ1Q==</Modulus><Exponent>AQAB</Exponent><P>zfvdBsMLlmo+4PAUYLgSV2xyyVa7ZqFjkJaAE4EbYuH24EoZjrzeiJR++D
FUT/GUhjfZ5eZ/5e29dXwk0sKUw6nHzBdBtOPp5fr4t5SKLEcWY+J+zLUSOlhG9NUkohFf6+Miy2Y7BLpXVrcl6UwXV0ak8KkTPB2l/aIMwYj5dgc=</
P><Q>wXV0sA3nDzoSDQA/4QSu/WIlBhkA3jZ7K7G9Z9rpP1A0vH+bZeyCIyo52u8ahGuYbubaizF1XMp+Xv3Mh2KmRbt7+UptwEwbFAUiiad2a312mqm
j7IJd7gRjGkyzKEm+6fpNeY3NFLNVNhccBqzhNkRoM22xnvQcImD10XVAakM=</Q><DP>wd1HdCLEWCfc0DYE59a2pINUMXyo2foRTDbpifHcRZ+ojAY
Rsc6+nsssCQnccXVMNVqBgSgEvfGYe+eAfMBX5SN5APPuioJrVGF2DsoFlZC+WPoGH0JYSoNlHO8yEDrMDaXzzH2GFHgQ1XOAged0nFbHzB1FFjJNVL5
cxRXWu6c=</DP><DQ>QDKuCk5SwubOXqoaiJ15RHRxPNjHRPZnYVSWOgSXKn9/QJ5H/0bA2NKGaHS4JAFgkEzjcRV0kNpRnUwztymxa6qPtWZRjWK0Ca
y6jVuZHIqB9UkeMLoCWZ3zFSMmwNPYGuUJGLFJwPjR6iU5E64C/nMs8QQR0WHIhFAQwvVZ7uk=</DQ><InverseQ>JckMSlJR10VZdnp83VPjrZ/Z+63
CGu3tWHm7f4DJ8IwjJWr8FlCpbSwiP6a4e9Upv6bUn/tOj2gY6MMq5G5yTKm2SCRvpUKRu4NCmWAt7vlFv0Z6pkXlTOpzvVjv3v16+dIZOA5Zn+v7+r1
xbdYdH20KRAbiBO3MfQP7s+VJJvM=</InverseQ><D>W1xrBr2hQOj1wgxWAgoK7IHbprEFrK+TnWmGA46SGPsbmHJ9fAVbY6fwHg7Wgmk4WHXLUCeLY
/Nu0eWIISfwh60Oe3ls2WC2k4qxyeSvQDBuLNb81U7WAUT9m9E1uK4QMCP3oxs1ybM80zTh7UMNgVK0WG+fbFUomVffcWTTqW+Fu12PEIO+UR/85oq+x
qVlTzYAEzt1OE9IhkYiRzi99ePXeH2gFltzJ/fb/7jLsDTkhM2eiYTGyOTZmBnen6c6a8b9LFTY4Bc0bGpk5ezHkub6F8p2ZgL/JgIOJMyRZICjDjs+9
k9PTmMTFsCF6xzHY15Fg25xIDYzIyx1rrRUjQ==</D></RSAKeyValue>",RSAKeyType::XMLString);
$rs =  $processor->encrypt("Hello,It's Works.");
echo $rs;
?>
with the front codes.you can easy to encrypt data by public key generate by .net programe.