Java数字签名不同于C＃

Question

我有以下c＃代码从私钥生成数字签名：

    static string Sign(string text, string certificate)
    {

        X509Certificate2 cert = new X509Certificate2(certificate, "TestPassword", X509KeyStorageFlags.Exportable);
        RSACryptoServiceProvider rsa = (RSACryptoServiceProvider)cert.PrivateKey;
        // Hash the data
        SHA1Managed sha1 = new SHA1Managed();
        ASCIIEncoding encoding = new ASCIIEncoding();
        byte[] data = encoding.GetBytes(text);
        byte[] hash = sha1.ComputeHash(data);
        // Sign the hash
        return System.Convert.ToBase64String(rsa.SignHash(hash, CryptoConfig.MapNameToOID("SHA1")));            
    }

然后，我创建了我认为等效的Java代码：

public static String signData(String dataToSign, String keyFile) { 
  FileInputStream keyfis = null;
  try {
    keyfis = new FileInputStream(fileName);
    KeyStore store = KeyStore.getInstance("PKCS12");
    store.load(keyfis, "TestPassword".toCharArray());
    KeyStore.PrivateKeyEntry pvk = (KeyStore.PrivateKeyEntry)store.
          getEntry("testkey", 
          new KeyStore.PasswordProtection("TestPassword".toCharArray()));
    PrivateKey privateKey = (PrivateKey)pvk.getPrivateKey();
    byte[] data = dataToSign.getBytes("US-ASCII");
    MessageDigest md = MessageDigest.getInstance("SHA1");
    byte[] hashed = md.digest(data);
    Signature rsa = Signature.getInstance("SHA1withRSA");
    rsa.initSign(privateKey);
    rsa.update(data);
    return Base64.encode(rsa.sign());
  } catch (Exception ex) {
    Logger.getLogger(this.getClass().getName()).log(Level.SEVERE, null, ex);
  } finally {
    if ( keyfis != null ) {
      try { keyfis.close() } catch (Exception ex) { keyfis = null; }
    }
  }
  return null;
}

不幸的是，数字签名不匹配。

任何帮助将不胜感激。提前致谢。

编辑 ：如果我从Java代码中删除MessageDigest，则输出是相同的。为什么？我以为需要哈希。

问候，尤金

Answer 1

Java sign方法基于Signature类的getInstance方法提供的算法进行哈希和签名，因此基本上您在Java中进行了两次哈希。