用Cryptico.js加密,用OpenSSL解密

时间:2013-05-12 09:29:43

标签: javascript encryption openssl rsa cryptico

我正在服务器上创建一个公钥/私钥,将密钥发送到JavaScript客户端,用于加密用户密码。客户端将密码发送到服务器,服务器使用私钥对其进行解密,但密码将返回null。我已经验证了支持这种情况的所有值都是正确的,所以具体来说就是加密/解密。我哪里错了?

可能,cryptico.js与php openssl不兼容吗?

图书馆信息:

https://github.com/wwwtyro/cryptico

http://www.php.net/manual/en/function.openssl-pkey-new.php

以下是相关的代码段:

PHP - 创建公钥/私钥

$config = array(
    "digest_alg" => "sha512",
    "private_key_bits" => 2048,
    "private_key_type" => OPENSSL_KEYTYPE_RSA,
);

// Create the private and public key
$res = openssl_pkey_new($config);

// Extract the private key from $res to $privateKey
openssl_pkey_export($res, $privateKey);

// Extract the public key from $res to $publicKey
$publicKey = openssl_pkey_get_details($res);
$publicKey = $publicKey["key"];

JavaScript - 客户端使用公钥加密数据。

var xhr = new XMLHttpRequest();
var data = new FormData();
xhr.open('POST', '/signUp2.php');
data.append('user', User);

var encryptedPassword = cryptico.encrypt(password, localStorage["publicKey"]);
data.append('password', encryptedPassword.cipher);

xhr.onreadystatechange = function()
{
    if(xhr.readyState == 4 && xhr.status == 200)
    {
        var jsonArray = JSON.parse(xhr.responseText);

        if(jsonArray[0] == "0")
        {
            alert("Account created.  You may now sign in.");
        }
        else
            alert("Error Code: " + jsonArray[0]);
    }
}
xhr.send(data);

PHP - 服务器收到加密密码并尝试解密失败

openssl_private_decrypt($encryptedPassword, $decryptedPassword, $row[1]);

1 个答案:

答案 0 :(得分:4)

cryptico.js可以与openssl一起使用,但我们必须对它进行一些修改。

它不直接识别pem格式的公钥(使用openssl)。我们必须在php端提取公钥的'n'和'e'部分:

$key = openssl_pkey_new(array( 
  'private_key_bits' => 1024,
  'private_key_type' => OPENSSL_KEYTYPE_RSA,
  'digest_alg' => 'sha256'
));

$detail = openssl_pkey_get_details($key);
$n = base64_encode($detail['rsa']['n']);
$e = bin2hex($detail['rsa']['e']);

另外,cryptico.js硬编码了公钥的'e'部分(参见api.js中publicKeyFromString的定义),所以我们需要解决这个问题:

my.publicKeyFromString = function(string)
{
  var tokens = string.split("|");
  var N = my.b64to16(tokens[0]);
  var E = tokens.length > 1 ? tokens[1] : "03";
  var rsa = new RSAKey();
  rsa.setPublic(N, E);
  return rsa
}

现在我们可以加密字符串了:

var publicKey = "{$n}|{$e}",
    encrypted = cryptico.encrypt("plain text", publicKey);

工作尚未完成。 cryptico.encrypt的结果不仅仅是由RSA加密。实际上,它由两部分组合而成:一个由RSA加密的aes密钥,以及由AES用该密钥加密的明文密码。如果我们只需要RSA,我们可以修改my.encrypt:

my.encrypt = function(plaintext, publickeystring, signingkey)
{
  var cipherblock = "";
  try
  {
    var publickey = my.publicKeyFromString(publickeystring);
    cipherblock += my.b16to64(publickey.encrypt(plaintext));
  }
  catch(err)
  {
    return {status: "Invalid public key"};
  } 
  return {status: "success", cipher: cipherblock};
}

现在我们可以使用openssl解密密码:

$private = openssl_pkey_get_private("YOUR PRIVATE KEY STRING IN PEM");
// $encrypted is the result of cryptico.encrypt() in javascript side
openssl_private_decrypt(base64_decode($encrypted), $decrypted, $private);
// now $decrypted holds the decrypted plain text