AWS S3直接上传返回无效签名(版本4签名)C#

本文介绍了AWS S3直接上传返回无效签名(版本4签名)C#的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在尝试直接从浏览器将文件上传到Amazon S3.我阅读了文档，并按照示例由亚马逊提供

I am trying to upload file to Amazon S3 directly from browser. I read the documentation and followed the example provided by amazon

除post方法外，示例方法均有效.错误消息为我们计算出的请求签名与您提供的签名不匹配.检查您的密钥和签名方法.

the example methods works except post method. the error message is The request signature we calculated does not match the signature you provided. Check your key and signing method.

我还检查了此代码样本.并将答案应用到代码中，仍然出现相同的错误.

I also checked this code sample. and applied the answer to the code and still getting the same error.

public class PolicyBuilder
{
    public static string Key = "Key";
    public static string Secret = "Secret";

    public static string GetS3PolicySignatureV4()
    {
        var policyBuilder = new StringBuilder();

        policyBuilder.AppendFormat("{{ \"expiration\": \"{0}\",\r\n", "2018-12-30T12:00:00.000Z");
        policyBuilder.Append("  \"conditions\": [\r\n");
        policyBuilder.Append("    [\"starts-with\", \"$key\", \"\"],\r\n");
        policyBuilder.AppendFormat("    {{\"x-amz-credential\": \"{0}\"}},\r\n",  Key + "/20180308/us-east-1/s3/aws4_request");
        policyBuilder.Append("    {\"x-amz-algorithm\": \"AWS4-HMAC-SHA256\"},\r\n");
        policyBuilder.Append("    {\"x-amz-date\": \"20180308T000000Z\" }\r\n");
        policyBuilder.Append("  ]\r\n}");

        var policyString = policyBuilder.ToString();
        var policyStringBytes = Encoding.UTF8.GetBytes(policyString);
        var policy = Convert.ToBase64String(policyStringBytes);

        byte[] signingKey = GetSignatureKey(Key, "20180308", "us-east-1", "s3");
        byte[] signature = HmacSHA256(policy, signingKey);
        var sig = ToHexString(signature, true);
        return sig;
    }

    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;
    }

    public static string ToHexString(byte[] data, bool lowercase)
    {
        var sb = new StringBuilder();
        for (var i = 0; i < data.Length; i++)
        {
            sb.Append(data[i].ToString(lowercase ? "x2" : "X2"));
        }
        return sb.ToString();
    }
}

这是表格:

<!DOCTYPE html>

<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="utf-8" />
    <title></title>
</head>
<body>
    <form action="http://MyBucket.s3.amazonaws.com/" method="post" enctype="multipart/form-data">
        <input type="hidden" name="key" value="/images/a5827206-ea2c-4fc6-a66b-aebde27d0ea3.jpg" />
        <input type="hidden" name="x-amz-credential" value="Key/20180308/us-east-1/s3/aws4_request" />
        <input type="hidden" name="x-amz-algorithm" value="AWS4-HMAC-SHA256" />
        <input type="hidden" name="x-amz-date" value="20180308T000000Z" />
        <input type="hidden" name="policy" value='<Base64PolicyResult>' />
        <input type="hidden" name="x-amz-signature" value="<GenerateSignature>" />
        File:
        <input type="file" name="file" /> <br />
        <input type="submit" name="submit" value="Upload to Amazon S3" />
    </form>
</body>
</html>

我仍然遇到相同的错误.我应该为Amazon S3的存储桶设置任何特定的策略吗?我的代码有什么问题吗? :(

I am still getting the same error. Should I set any specific policy for my bucket on amazon s3?is there anything wrong in my code? :(

版本4签名

AWS S3直接上传返回无效签名(版本4签名)C#

问题描述

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