/**
* Crypt_RSA_KeyPair constructor.
*
* @param int $key_len bit length of key pair, which will be generated in constructor
* @param string $wrapper_name
* Name of math wrapper, which will be used to
* perform different operations with big integers.
* See contents of Crypt/RSA/Math folder for examples of wrappers.
* Read docs/Crypt_RSA/docs/math_wrappers.txt for details.
* @param string $error_handler name of error handler function
* @param callback $random_generator function which will be used as random generator
*
* @access public
*/
function Crypt_RSA_KeyPair($key_len, $wrapper_name = 'default', $error_handler = '', $random_generator = null)
{
// set error handler
$this->setErrorHandler($error_handler);
// try to load math wrapper
$obj =& Crypt_RSA_MathLoader::loadWrapper($wrapper_name);
if ($this->isError($obj)) {
// error during loading of math wrapper
$this->pushError($obj);
return;
}
$this->_math_obj =& $obj;
// set random generator
if (!$this->setRandomGenerator($random_generator)) {
// error in setRandomGenerator() function
return;
}
if (is_array($key_len)) {
// ugly BC hack - it is possible to pass RSA private key attributes [version, n, e, d, p, q, dmp1, dmq1, iqmp]
// as associative array instead of key length to Crypt_RSA_KeyPair constructor
$rsa_attrs = $key_len;
// convert attributes to big integers
$attr_names = $this->_get_attr_names();
foreach ($attr_names as $attr) {
if (!isset($rsa_attrs[$attr])) {
$this->pushError("missing required RSA attribute [{$attr}]");
return;
}
${$attr} = $this->_math_obj->bin2int($rsa_attrs[$attr]);
}
// check primality of p and q
if (!$this->_math_obj->isPrime($p)) {
$this->pushError("[p] must be prime");
return;
}
if (!$this->_math_obj->isPrime($q)) {
$this->pushError("[q] must be prime");
return;
}
// check n = p * q
$n1 = $this->_math_obj->mul($p, $q);
if ($this->_math_obj->cmpAbs($n, $n1)) {
$this->pushError("n != p * q");
return;
}
// check e * d = 1 mod (p-1) * (q-1)
$p1 = $this->_math_obj->dec($p);
$q1 = $this->_math_obj->dec($q);
$p1q1 = $this->_math_obj->mul($p1, $q1);
$ed = $this->_math_obj->mul($e, $d);
$one = $this->_math_obj->mod($ed, $p1q1);
if (!$this->_math_obj->isOne($one)) {
$this->pushError("e * d != 1 mod (p-1)*(q-1)");
return;
}
// check dmp1 = d mod (p-1)
$dmp = $this->_math_obj->mod($d, $p1);
if ($this->_math_obj->cmpAbs($dmp, $dmp1)) {
$this->pushError("dmp1 != d mod (p-1)");
return;
}
// check dmq1 = d mod (q-1)
$dmq = $this->_math_obj->mod($d, $q1);
if ($this->_math_obj->cmpAbs($dmq, $dmq1)) {
$this->pushError("dmq1 != d mod (q-1)");
return;
}
// check iqmp = 1/q mod p
$q1 = $this->_math_obj->invmod($iqmp, $p);
if ($this->_math_obj->cmpAbs($q, $q1)) {
$this->pushError("iqmp != 1/q mod p");
return;
}
// try to create public key object
$public_key = new Crypt_RSA_Key($rsa_attrs['n'], $rsa_attrs['e'], 'public', $wrapper_name, $error_handler);
if ($public_key->isError()) {
// error during creating public object
$this->pushError($public_key->getLastError());
return;
}
// try to create private key object
$private_key = new Crypt_RSA_Key($rsa_attrs['n'], $rsa_attrs['d'], 'private', $wrapper_name, $error_handler);
if ($private_key->isError()) {
// error during creating private key object
$this->pushError($private_key->getLastError());
return;
}
$this->_public_key = $public_key;
$this->_private_key = $private_key;
$this->_key_len = $public_key->getKeyLength();
$this->_attrs = $rsa_attrs;
} else {
// generate key pair
if (!$this->generate($key_len)) {
// error during generating key pair
return;
}
}
}
