C# implementation to obtain smtp password from signed secret key for AWS SES

program.cs

public class Program
{
    public static void Main(string[] args)
    {
        Console.WriteLine(GetCredential("YOUR_SECRET_KEY"));
    }
    
    private static byte[] sign(byte[] key, string value)
    {
        return new System.Security.Cryptography.HMACSHA256(key).ComputeHash(System.Text.Encoding.UTF8.GetBytes(value));
    }

    private static string GetCredential(string secret, string region = "us-east-1") //'us-east-1','us-west-2','eu-west-1'
    {
        string DATE = "11111111";
        string SERVICE = "ses";
        string MESSAGE = "SendRawEmail";
        string TERMINAL = "aws4_request";
        byte[] VERSION = new byte[] { 0x04 };

        var signature = sign(System.Text.Encoding.UTF8.GetBytes("AWS4" + secret), DATE);
        signature = sign(signature, region);
        signature = sign(signature, SERVICE);
        signature = sign(signature, TERMINAL);
        signature = sign(signature, MESSAGE);
        var signatureAndVersion = VERSION.Concat(signature).ToArray();

        return System.Convert.ToBase64String(signatureAndVersion);
    }
}

ping back https://docs.aws.amazon.com/ses/latest/DeveloperGuide/smtp-credentials.html

IAM secret key to SMTP password