时间戳

首页 > 解决方案 > Amazon product lookup signature mismatch

api - Amazon product lookup signature mismatch

问题描述

This is the response I'm getting: The request signature we calculated does not match the signature you provided.

Here is the code I'm using to generate the signature:

static byte[] HmacSHA256(String data, byte[] key)
{
    String algorithm = "HmacSHA256";
    KeyedHashAlgorithm kha = KeyedHashAlgorithm.Create(algorithm);
    kha.Key = key;

    return kha.ComputeHash(Encoding.UTF8.GetBytes(data));
}

static byte[] getSignatureKey(String key, String dateStamp, String regionName, String serviceName)
{
    byte[] kSecret = Encoding.UTF8.GetBytes(("AWS4" + key).ToCharArray());
    byte[] kDate = HmacSHA256(dateStamp, kSecret);
    byte[] kRegion = HmacSHA256(regionName, kDate);
    byte[] kService = HmacSHA256(serviceName, kRegion);
    byte[] kSigning = HmacSHA256("aws4_request", kService);

    return kSigning;
}

When I use Amazon's test settings, I get the correct signature 

key = 'wJalrXUtnFEMI/K7MDENG+bPxRfiCYEXAMPLEKEY'
dateStamp = '20120215'
regionName = 'us-east-1'
serviceName = 'iam'

However, when I put my live settings in, I get the not matching error.

Here is what I'm using to get my signature:

var reqSig = getSignatureKey("[my secret key]", dateStamp, "us-west-2","AWSECommerceService");

This is what I'm submitting (I'm just testing it in a browser, for now):

ecs.amazonaws.com/onca/xml?Service=AWSECommerceService&AWSAccessKeyId=[my
access key that corresponds with the secret
key]&Operation=ItemLookup&IdType=UPC&ItemId=635753490879&Timestamp=2019-01-24T19:14:55.2644840Z&Signature=32BA07ECE67F3177BF2EA02923E624D612A45FAA144ED0E43BDDC0DF6574EAC3

I'm not sure if it has to do with the region -- us-west-2 in my case -- because there is no place on the request for a region. I'm not sure how Amazon can test my signature against my parameters if I can't specify what region it is and I've used the region to calculate the signature.

What am I missing?

标签： apirequestamazonsignature

解决方案

好的。在花了几天的时间经历这个之后，这是我必须做的：

/*

    DOCUMENTATION: https://docs.aws.amazon.com/AWSECommerceService/latest/DG/rest-signature.html#rest_detailedexample
*/

    var itemID = "0679722769";
    var accessKeyID = "AKIAIOSFODNN7EXAMPLE";
    var timeStamp = DateTime.UtcNow.ToString("o");
    var req = $"Service=AWSECommerceService&AWSAccessKeyId={accessKeyID}&Operation=ItemLookup&IdType=UPC&ItemId={itemID}&Version=2013-08-01&Timestamp={timeStamp}";
    req = req.Replace(":", "%3A").Replace(",", "%2C"); //UrlDecode certain characters
    var reqlist = req.Split('&').ToArray(); //we need to sort our key/value pairs
    Array.Sort(reqlist);
    req = String.Join("&", reqlist); //join everything back
    var reqToSign = $@"GET
webservices.amazon.com
/onca/xml
{req}".Replace("\r", ""); //create the request for signing. We need to replace microsofts's crlf with just a lf; Make sure there are no leading spaces after the linefeeds.

    var signage = getSignatureKey("1234567890",reqToSign);
    req = $"http://webservices.amazon.com/onca/xml?{req}&Signature={signage}"; //create our request with the signature appended.
    return req;
}

private static byte[] HmacSHA256(String data, byte[] key)
{
    String algorithm = "HmacSHA256";
    KeyedHashAlgorithm kha = KeyedHashAlgorithm.Create(algorithm);
    kha.Key = key;

    return kha.ComputeHash(Encoding.UTF8.GetBytes(data));
}


private static string getSignatureKey(string key, string stringToSign)
{
    byte[] kSecret = Encoding.UTF8.GetBytes(key.ToCharArray());
    byte[] kSigning = HmacSHA256(stringToSign, kSecret);
    return WebUtility.UrlEncode(Convert.ToBase64String(kSigning));
}

与在这里和其他地方找到的大多数答案相反，这是唯一可行的方法。必须对整个请求进行哈希处理，而不仅仅是特定参数。我无法与其他亚马逊服务交谈，但商务服务必须这样做。

相当多的答案引用了这个：https ://docs.aws.amazon.com/general/latest/gr/sigv4-calculate-signature.html或这个：Amazon API 在 C# .NET 中生成请求签名

正如我在问题中所说，这肯定是不正确的。如果您没有传递区域参数，亚马逊如何创建相同的签名，因为它没有所有信息。

无论如何，这现在有效。

推荐阅读