$config = array(   //"digest_alg" => "sha512",   "private_key_bits" => 512,           //字節數  512 1024 2048  4096 等   "private_key_type" => OPENSSL_KEYTYPE_RSA,   //加密類型 );    //1.創建公鑰和私鑰  返回資源 $res = openssl_pkey_new($config);  //從得到的資源中獲取私鑰  并把私鑰賦給$privKeyopenssl_pkey_export($res, $privKey);  //從得到的資源中獲取私鑰  并把私鑰賦給$pubKey$pubKey = openssl_pkey_get_details($res);  $pubKey = $pubKey["key"]; var_dump(array('privKey'=>$privKey,'pubKey'=>$pubKey)); die; //2.加密解密數據 要加密的數據 $data = 'plaintext data goes here';             //對$data進行加密 要加密的數據字符串 得到加密后的數據 加密所需要的公鑰openssl_public_encrypt($data, $encrypted, $pubKey); echo base64_encode($encrypted);  //對加密后的數據進行解密 解密的數據 得到解密后的數據 解密所需要的私鑰$decrypted = base64_decode($encrypted);openssl_private_decrypt($encrypted, $decrypted, $privKey); echo $decrypted;  //3.一個加密解密類 class rsa {   private $public_key = ''; //公密鑰   private $private_key = ''; //私密鑰   private $public_key_resource = ''; //公密鑰資源   private $private_key_resource = ''; //私密鑰資源   /**    * 架構函數    * @param [string] $public_key_file [公密鑰文件地址]    * @param [string] $private_key_file [私密鑰文件地址]    */   public function __construct($public_key,$private_key) {     $this->public_key = $public_key;    $this->private_key = $private_key;  if(false == ($this->public_key_resource = $this->is_bad_public_key($this->public_key)) || false == ($this->private_key_resource = $this->is_bad_private_key($this->private_key))) {   throw new Exception('public key or private key no usable');  }   }   private function is_bad_public_key($public_key) {     return openssl_pkey_get_public($public_key);   }   private function is_bad_private_key($private_key) {     return openssl_pkey_get_private($private_key);   }   /**    * 生成一對公私密鑰 成功返回 公私密鑰數組 失敗 返回 false    */   public function create_key() {     $res = openssl_pkey_new();     if($res == false) return false;     openssl_pkey_export($res, $private_key);     $public_key = openssl_pkey_get_details($res);     return array('public_key'=>$public_key["key"],'private_key'=>$private_key);   }   /**    * 用私密鑰加密    */   public function private_encrypt($input) {     openssl_private_encrypt($input,$output,$this->private_key_resource);     return base64_encode($output);   }   /**    * 解密 私密鑰加密后的密文    */   public function public_decrypt($input) {     openssl_public_decrypt(base64_decode($input),$output,$this->public_key_resource);     return $output;   }   /**    * 用公密鑰加密    */   public function public_encrypt($input) {     openssl_public_encrypt($input,$output,$this->public_key_resource);     return base64_encode($output);   }   /**    * 解密 公密鑰加密后的密文    */   public function private_decrypt($input) {     openssl_private_decrypt(base64_decode($input),$output,$this->private_key_resource);     return $output;   } } $private_key = '-----BEGIN RSA PRIVATE KEY----- MIICXQIBAAKBgQC3//sR2tXw0wrC2DySx8vNGlqt3Y7ldU9+LBLI6e1KS5lfc5jl TGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2klBd6h4wrbbHA2XE1sq21ykja/ Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o2n1vP1D+tD3amHsK7QIDAQAB AoGBAKH14bMitESqD4PYwODWmy7rrrvyFPEnJJTECLjvKB7IkrVxVDkp1XiJnGKH 2h5syHQ5qslPSGYJ1M/XkDnGINwaLVHVD3BoKKgKg1bZn7ao5pXT+herqxaVwWs6 ga63yVSIC8jcODxiuvxJnUMQRLaqoF6aUb/2VWc2T5MDmxLhAkEA3pwGpvXgLiWL 3h7QLYZLrLrbFRuRN4CYl4UYaAKokkAvZly04Glle8ycgOc2DzL4eiL4l/+x/gaq deJU/cHLRQJBANOZY0mEoVkwhU4bScSdnfM6usQowYBEwHYYh/OTv1a3SqcCE1f+ qbAclCqeNiHajCcDmgYJ53LfIgyv0wCS54kCQAXaPkaHclRkQlAdqUV5IWYyJ25f oiq+Y8SgCCs73qixrU1YpJy9yKA/meG9smsl4Oh9IOIGI+zUygh9YdSmEq0CQQC2 4G3IP2G3lNDRdZIm5NZ7PfnmyRabxk/UgVUWdk47IwTZHFkdhxKfC8QepUhBsAHL QjifGXY4eJKUBm3FpDGJAkAFwUxYssiJjvrHwnHFbg0rFkvvY63OSmnRxiL4X6EY yI9lblCsyfpl25l7l5zmJrAHn45zAiOoBrWqpM5edu7c -----END RSA PRIVATE KEY-----';$public_key = '-----BEGIN PUBLIC KEY----- MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC3//sR2tXw0wrC2DySx8vNGlqt 3Y7ldU9+LBLI6e1KS5lfc5jlTGF7KBTSkCHBM3ouEHWqp1ZJ85iJe59aF5gIB2kl Bd6h4wrbbHA2XE1sq21ykja/Gqx7/IRia3zQfxGv/qEkyGOx+XALVoOlZqDwh76o 2n1vP1D+tD3amHsK7QIDAQAB -----END PUBLIC KEY-----';$rsa = new rsa($public_key,$private_key);  $str = '加密解密'; $str = $rsa->public_encrypt($str); //用公密鑰加密 echo $str,'</br>'; $str = $rsa->private_decrypt($str); //用私密鑰解密 echo $str,'</br>'; //============================================================= $str = $rsa->private_encrypt($str); //用私密鑰加密 echo $str,'</br>'; $str = $rsa->public_decrypt($str); //用公密鑰解密 echo $str,'</br>';