Question

我正在使用RSA加密/解密和证书。具体来说，我尝试使用证书的公钥进行加密，然后，当尝试使用与该证书对应的私钥进行解密时，会收到错误：

System.Security.Cryptography.CryptographicException: Bad Key.

   at System.Security.Cryptography.CryptographicException.ThrowCryptographicException(Int32 hr)
   at System.Security.Cryptography.RSACryptoServiceProvider.DecryptKey(SafeKeyHandle pKeyContext, Byte[] pbEncryptedKey, Int3
2 cbEncryptedKey, Boolean fOAEP, ObjectHandleOnStack ohRetDecryptedKey)
   at System.Security.Cryptography.RSACryptoServiceProvider.Decrypt(Byte[] rgb, Boolean fOAEP)

代码是：

private void TestCertificates2()
{
    //////////////////////////////////////////////////////
    // SENDER CODE
    //////////////////////////////////////////////////////

    // get certificate
    var certSender = new X509Certificate2(@"C:\Test.cer");

    // encrypt with public key
    var providerSender = (RSACryptoServiceProvider)certSender.PublicKey.Key;
    var plainSender = Encoding.Default.GetBytes("this is plain text");
    var cipher = providerSender.Encrypt(plainSender, false);

    //////////////////////////////////////////////////////
    // RECEIVER CODE
    //////////////////////////////////////////////////////

    // get certificate
    var store = new X509Store("MY", StoreLocation.LocalMachine);
    store.Open(OpenFlags.ReadOnly | OpenFlags.OpenExistingOnly);
    var certReceiver = store.Certificates.Find(X509FindType.FindBySubjectName, "Test Subject", false)[0];

    // decrypt with private key
    var providerReceiver = (RSACryptoServiceProvider)certReceiver.PrivateKey;
    var plainReceiver = providerReceiver.Decrypt(cipher, false);

    // check they are same
    if (plainSender.Equals(plainReceiver))
    {
        Console.WriteLine("Same!");
    }
}

作为参考，证书是通过

创建和安装的

makecert.exe Test.cer -n "CN=Test Subject" -sr LocalMachine -ss My

有人能发现我做错了吗？提前谢谢！

Answer 1

好的，发现问题所在：需要告诉makecert 1）证书的主题密钥类型是“交换” 2）将私钥标记为可导出

所以makecert看起来像是

makecert.exe Test.cer -r -n "CN=Test Subject" -sr LocalMachine -ss My -sky Exchange -pe

“System.Security.Cryptography.CryptographicException：Bad Key。”对于RSACryptoServiceProvider.Decrypt（）

1 个答案: