如何在C#中生成HMAC-SHA1？

Question

我正在尝试使用C#来使用REST API.API创建者提供了PHP,Ruby和Java的示例库.我被挂在它的一部分,我需要生成一个HMAC.

以下是它们提供的示例库中的完成方式.

PHP

hash_hmac('sha1', $signatureString, $secretKey, false);

红宝石

digest = OpenSSL::Digest::Digest.new('sha1')
return OpenSSL::HMAC.hexdigest(digest, secretKey, signatureString)

Java的

SecretKeySpec signingKey = new SecretKeySpec(secretKey.getBytes(), HMAC_SHA1_ALGORITHM);

Mac mac = null;
mac = Mac.getInstance(HMAC_SHA1_ALGORITHM);
mac.init(signingKey);

byte[] bytes = mac.doFinal(signatureString.getBytes());

String form = "";
for (int i = 0; i < bytes.length; i++)
{
    String str = Integer.toHexString(((int)bytes[i]) & 0xff);
    if (str.length() == 1)
    {
        str = "0" + str;
    }

    form = form + str;
}
return form;

这是我在C#中的尝试.它不起作用.更新:下面的C#示例工作得很好.我发现真正的问题是由于我的换行符中的一些跨平台差异signatureString.

var enc = Encoding.ASCII;
HMACSHA1 hmac = new HMACSHA1(enc.GetBytes(secretKey));
hmac.Initialize();

byte[] buffer = enc.GetBytes(signatureString);
return BitConverter.ToString(hmac.ComputeHash(buffer)).Replace("-", "").ToLower();

Answer 1

Vimvq1987答案的扩展:

return hashValue.ToString();不会产生您想要/需要的输出.您必须将数组中的字节转换为hashValue十六进制字符串表示形式.
可以return BitConverter.toString(hashValue);这么简单(打印大写字母AF)或者如果你喜欢它有点复杂:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security.Cryptography;
using System.IO;

namespace ConsoleApplication1
{
    class Program
    {
        public static string Encode(string input, byte[] key)
        {
            HMACSHA1 myhmacsha1 = new HMACSHA1(key);
            byte[] byteArray = Encoding.ASCII.GetBytes(input);
            MemoryStream stream = new MemoryStream(byteArray);
            return myhmacsha1.ComputeHash(stream).Aggregate("", (s, e) => s + String.Format("{0:x2}",e), s => s );
        }


        static void Main(string[] args)
        {
            byte[] key = Encoding.ASCII.GetBytes("abcdefghijklmnopqrstuvwxyz");
            string input = "";
            foreach (string s in new string[] { "Marry", " had", " a", " little", " lamb" })
            {
                input += s;
                System.Console.WriteLine( Encode(input, key) );
            }
            return;
        }
    }
}

打印

3545e064fb59bc4bfc02b6e1c3d4925c898aa504
3249f4c8468d4d67f465937da05b809eaff22fdb
87baaadf5d096677f944015e53d283834eb1e943
6325376820c29a09e3ab30db000033aa71d6927d
54579b0146e2476595381d837ee38863be358213

我得到了完全相同的结果

<?php
$secretKey = 'abcdefghijklmnopqrstuvwxyz';

$signatureString = '';
foreach( array('Marry',' had',' a',' little',' lamb') as $s ) {
    $signatureString .= $s;
    echo hash_hmac('sha1', $signatureString, $secretKey, false), "\n";
}

编辑:Dmitriy Nemykin建议进行以下编辑

public static string Encode(string input, byte[] key)
{
    byte[] byteArray = Encoding.ASCII.GetBytes(input);
    using(var myhmacsha1 = new HMACSHA1(key))
    {
        var hashArray = myhmacsha1.ComputeHash(byteArray);
        return hashArray.Aggregate("", (s, e) => s + String.Format("{0:x2}",e), s => s );
    }
}

被拒绝了.但正如詹姆斯在对这个答案的评论中已经指出的那样,至少使用声明 是一个好点.

Answer 2

这个网站有很多不同语言的例子:http://jokecamp.wordpress.com/2012/10/21/examples-of-creating-base64-hashes-using-hmac-sha256-in-different-languages/

编写本文时的c#实现是:

private string CreateToken(string message, string secret)
{
 secret = secret ?? "";
 var encoding = new System.Text.ASCIIEncoding();
 byte[] keyByte = encoding.GetBytes(secret);
 byte[] messageBytes = encoding.GetBytes(message);
 using (var hmacsha256 = new HMACSHA256(keyByte))
 {
 byte[] hashmessage = hmacsha256.ComputeHash(messageBytes);
 return Convert.ToBase64String(hashmessage);
 }
}

Answer 3

试试这个:

http://msdn.microsoft.com/en-us/library/system.security.cryptography.hmacsha1.aspx

快速而肮脏的代码:

public string Encode(string input, byte [] key)
{
        HMACSHA1 myhmacsha1 = new HMACSHA1(key);
        byte[] byteArray = Encoding.ASCII.GetBytes( input );
        MemoryStream stream = new MemoryStream( byteArray ); 
        byte[] hashValue = myhmacsha1.ComputeHash(stream);
        return hashValue.ToString();
}