C# vs Java HmacSHA1，然后是base64

Question

我有一个java代码示例，使用HMAC-SHA1算法(RFC2104.)计算摘要，然后使用Base64编码(RFC2045)进行编码。

下面是java代码

public static String buildDigest(String key, String idString) throws SignatureException {


 try {
    String algorithm = "HmacSHA1";
    Charset charset = Charset.forName("utf-8");
    SecretKeySpec signingKey = new SecretKeySpec(key.getBytes(), algorithm);
    Mac mac = Mac.getInstance(algorithm);
    mac.init(signingKey);
    return new String(Base64.encodeBase64(mac.doFinal(idString.getBytes(charset))), charset);
  } catch (Exception e) {
    throw new SignatureException("Failed to generate HMAC : " + e.getMessage());
  }
}

我在Stack Overflow中找到了答案，下面是C#代码

   private string EncodeHMAC(string input, byte[] key)
    {
        HMACSHA1 myhmacsha1 = new HMACSHA1(key);
        byte[] byteArray = Encoding.UTF8.GetBytes(input);
       // MemoryStream stream = new MemoryStream(byteArray);
        var hashValue = myhmacsha1.ComputeHash(byteArray);
        return hashValue.Aggregate("", (s, e) => s + String.Format("{0:x2}", e), s => s);
    }

    private string EncodeTo64(string toEncode)
    {
        byte[] toEncodeAsBytes = System.Text.UTF8Encoding.UTF8.GetBytes(toEncode);

        string returnValue = System.Convert.ToBase64String(toEncodeAsBytes);

        return returnValue;
    }

我没有得到在tutorial that I am following中显示的正确结果

Answer 1

试试这个：

// This method will return the base 64 encoded string using the given input and key.
private string EncodeHMAC(string input, byte[] key)
{
    HMACSHA1 hmac = new HMACSHA1(key);
    byte[] stringBytes = Encoding.UTF8.GetBytes(input);
    byte[] hashedValue = hmac.ComputeHash(stringBytes);
    return Convert.ToBase64String(hashedValue);
}

我认为您没有正确地将散列值转换为base64字符串。

Answer 2

我使用此函数来实现REST web服务调用的身份验证。发送者和接收者使用相同的编码是很重要的。

不幸的是，我花了一段时间才找到与这个C#版本相匹配的PHP。

private bool ValidateHash(String uid, String hash, DataToSign data) {
        StringBuilder strToSign = new StringBuilder();

        strToSign.Append(data.HttpMethod + '\n');
        strToSign.Append(data.Date.ToString("r") + '\n');
        strToSign.Append(data.Uri);

        Byte[] secretBytes = UTF8Encoding.UTF8.GetBytes(this._secretKey);
        HMACSHA1 hmac = new HMACSHA1(secretBytes);

        Byte[] dataBytes = UTF8Encoding.UTF8.GetBytes(strToSign.ToString());
        Byte[] calcHash = hmac.ComputeHash(dataBytes);
        String calcHashString = Convert.ToBase64String(calcHash);

        if (calcHashString.Equals(hash)) {
            if (log.IsDebugEnabled) log.Debug(uid + " - [ValidateHash] HMAC is valid.");
            return true;
        }
        return false;
    }

希望这能有所帮助！