class RSAEncryptTest {
  const PRIVATE_KEY = "-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: DES-EDE3-CBC,C222ABDFB89D4349
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-----END RSA PRIVATE KEY-----
";
  const PUBLIC_KEY = "-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDXZaD7aXaL6WOGFqfu8M1C55z2
d8gylu2y6jRdyc9wPt14tmkKofJE9vosD4mCRAArw0yS633g0b0Ln9f1IVFg2ZE1
5kBASpQf42D08Jb/L93GHPBUhvFBUy8pUAKwqa6braW/4ZMNj40f5PGhqkyH0VIV
03aeS8yd1lPPMtX1XwIDAQAB
-----END PUBLIC KEY-----";
  private static $private_key;
  private static $public_key;
 
  public static function private_encrypt($str){
    self::setup_key();
    if(openssl_private_encrypt($str, $encrypted, self::$private_key))
      return $encrypted;
  }
  public static function private_decrypt($str){
    self::setup_key();
    if(openssl_private_decrypt($str, $decrypted, self::$private_key))
      return $decrypted;
  }
  public static function public_decrypt($str){
    self::setup_key();
    if(openssl_public_decrypt($str, $decrypted, self::$public_key))
      return $decrypted;
  }
  public static function public_encrypt($str){
    self::setup_key();
    if(openssl_public_encrypt($str, $encrypted, self::$public_key))
      return $encrypted;
  }
  private static function setup_key(){
    if (!self::$private_key){
      // 这里的test就是在生成证书的时候设置的私钥密码
      self::$private_key = openssl_pkey_get_private(self::PRIVATE_KEY, "1234");
    }
    if (!self::$public_key)
      self::$public_key = openssl_pkey_get_public(self::PUBLIC_KEY);
  }
}
//公钥加密字符串 xxx
$public_encrypt=RSAEncryptTest::public_encrypt("xxx");
echo  "public_encrypt:\n";
echo  base64_encode($private_encrypt) ;
echo  "\n";

//私钥解密
$private_decrypt=RSAEncryptTest::private_decrypt($public_encrypt);