Question

使用PHP代码对消息进行签名（使用phpseclib 2.0）：

function sign($plaintext, $key, $password) {
    $rsa = new RSA();

    $rsa->setPassword($password);
    $rsa->loadKey(file_get_contents($key));

    $rsa->setSignatureMode(CRYPT_RSA_SIGNATURE_PKCS1);
    $signature = $rsa->sign(hash('sha256', $plaintext));

    return base64_encode($signature);
}

公钥和私钥格式为PEM。我需要用C＃验证这个签名。我正在尝试此代码，但它返回false：

public static bool VerifyData(string originalMessage, string signedMessage, RSAParameters publicKey)
{
    bool success = false;
    using (var rsa = new RSACryptoServiceProvider())
    {
    var encoder = new UTF8Encoding();
    byte[] bytesToVerify = encoder.GetBytes(originalMessage);
    byte[] signedBytes = Convert.FromBase64String(signedMessage);
    try
    {
        rsa.ImportParameters(publicKey);

        SHA256Managed Hash = new SHA256Managed();

        byte[] hashedData = Hash.ComputeHash(bytesToVerify);
        success = rsa.VerifyData(hashedData, CryptoConfig.MapNameToOID("SHA256"), signedBytes);
    }
    catch (CryptographicException e)
    {
        Console.WriteLine(e.Message);
    }
    finally
    {
        rsa.PersistKeyInCsp = false;
    }
    }
    return success;
}

用法：

RSACryptoServiceProvider rsa = PemKeyUtils.PemKeyUtils.GetRSAProviderFromPemFile("public.key");
MessageBox.Show(VerifyData("my message", @"ZpQMPYlMIgME/H0sRYBnyEf/yJ/eBc5bznYZ2nMFn/I6Ts3u8P3x0QgzbUxPnhUgfKhcrEC2UgffyzWzCfwT3Bs+lm6Q89N5bkWK08WKnWaFxr2GQ6+gNyPyUKUgfy851xIHU7EMR6bZt/IndPC+lAAXSxxddPwLelrI8ktgyMVvMUzfCh3AeNCBuY5sSRwkAKH2myPBThJKNjKSZVEb4tO4oiPPWlBuifqmWvbQeMFuKANY0dZNCUFVjlnkaHnwVNzVs1BhNTEML2MKmWvKofafbtcG8J1F+7PapppZwT7OFqhosCSrrzRX49cR4y/7b0syJozmJSebKDpy6FPefA==", rsa.ExportParameters(false)).ToString());

来自this answer的PemKeyUtils课程。

出了什么问题？如何用C＃验证签名？

Answer 1

VerifyData()计算哈希本身，因此您最终会在C＃代码中对数据进行两次哈希处理。只需将数据直接提供给VerifyData()，而无需自己进行散列。

编辑：好的，现在我看到你在php端也是两次哈希，第一次用SHA1，第二次用SHA256。只需使用SHA256哈希一次，就像显示in the examples一样。

function sign($plaintext, $key, $password) {
    $rsa = new RSA();

    $rsa->setPassword($password);
    $rsa->loadKey(file_get_contents($key));

    $rsa->setSignatureMode(CRYPT_RSA_SIGNATURE_PKCS1);
    $rsa->setHash('sha256')
    $signature = $rsa->sign($plaintext);

    return base64_encode($signature);
}

用PHP签名，用C＃验证

1 个答案: