使用openssl实现rsa非对称加密算法示例_php实例

代码如下:
/**
* 使用openssl实现非对称加密
* @since 2010-07-08
*/
class Rsa
{
/**
* private key
*/
private $_privKey;

/**
* public key
*/
private $_pubKey;

/**
* the keys saving path
*/
private $_keyPath;

/**
* the construtor,the param $path is the keys saving path
*/
public function __construct($path)
{
if(empty($path) || !is_dir($path)){
throw new Exception('Must set the keys save path');
}

$this->_keyPath = $path;
}

/**
* create the key pair,save the key to $this->_keyPath
*/
public function createKey()
{
$r = openssl_pkey_new();
openssl_pkey_export($r, $privKey);
file_put_contents($this->_keyPath . DIRECTORY_SEPARATOR . 'priv.key', $privKey);
$this->_privKey = openssl_pkey_get_public($privKey);

$rp = openssl_pkey_get_details($r);
$pubKey = $rp['key'];
file_put_contents($this->_keyPath . DIRECTORY_SEPARATOR . 'pub.key', $pubKey);
$this->_pubKey = openssl_pkey_get_public($pubKey);
}

/**
* setup the private key
*/
public function setupPrivKey()
{
if(is_resource($this->_privKey)){
return true;
}
$file = $this->_keyPath . DIRECTORY_SEPARATOR . 'priv.key';
$prk = file_get_contents($file);
$this->_privKey = openssl_pkey_get_private($prk);
return true;
}

/**
* setup the public key
*/
public function setupPubKey()
{
if(is_resource($this->_pubKey)){
return true;
}
$file = $this->_keyPath . DIRECTORY_SEPARATOR . 'pub.key';
$puk = file_get_contents($file);
$this->_pubKey = openssl_pkey_get_public($puk);
return true;
}

/**
* encrypt with the private key
*/
public function privEncrypt($data)
{
if(!is_string($data)){
return null;
}

$this->setupPrivKey();

$r = openssl_private_encrypt($data, $encrypted, $this->_privKey);
if($r){
return base64_encode($encrypted);
}
return null;
}

/**
* decrypt with the private key
*/
public function privDecrypt($encrypted)
{
if(!is_string($encrypted)){
return null;
}

$this->setupPrivKey();

$encrypted = base64_decode($encrypted);

$r = openssl_private_decrypt($encrypted, $decrypted, $this->_privKey);
if($r){
return $decrypted;
}
return null;
}

/**
* encrypt with public key
*/
public function pubEncrypt($data)
{
if(!is_string($data)){
return null;
}

$this->setupPubKey();

$r = openssl_public_encrypt($data, $encrypted, $this->_pubKey);
if($r){
return base64_encode($encrypted);
}
return null;
}

/**
* decrypt with the public key
*/
public function pubDecrypt($crypted)
{
if(!is_string($crypted)){
return null;
}

$this->setupPubKey();

$crypted = base64_decode($crypted);

$r = openssl_public_decrypt($crypted, $decrypted, $this->_pubKey);
if($r){
return $decrypted;
}
return null;
}

public function __destruct()
{
@ fclose($this->_privKey);
@ fclose($this->_pubKey);
}

}

//以下是一个简单的测试demo，如果不需要请删除
$rsa = new Rsa('ssl-key');

//私钥加密，公钥解密
echo 'source：我是老鳖
';
$pre = $rsa->privEncrypt('我是老鳖');
echo 'private encrypted:
' . $pre . '
';

$pud = $rsa->pubDecrypt($pre);
echo 'public decrypted:' . $pud . '
';

//公钥加密，私钥解密
echo 'source:干IT的
';
$pue = $rsa->pubEncrypt('干IT的');
echo 'public encrypt:
' . $pue . '
';

$prd = $rsa->privDecrypt($pue);
echo 'private decrypt:' . $prd;
?>


需要注意的是apache要支持OpenSSL