Why does this method for computing a SHA-256 hash always return a string of 44 characters?
First off, please ignore that there is no salt. I removed the salt in order to simplify things as much as possible.
The following always outputs a 44 character string:
using System;
using System.Collections.Generic;
using System.Text;
using System.Security.Cryptography;
namespace ConsoleApplication1
{
class Program
{
private static HashAlgorithm hashAlgorithm = new SHA256CryptoServiceProvider();
static void Main(string[] args)
{
string blah = ComputeHash("PasswordLongBlah646468468Robble");
Console.WriteLine(blah.Length);
Console.WriteLine(blah);
}
private static string ComputeHash(string input)
{
Byte[] inputBytes = En开发者_如何学运维coding.UTF8.GetBytes(input);
Byte[] hashedBytes = hashAlgorithm.ComputeHash(inputBytes);
return Convert.ToBase64String(hashedBytes);
}
}
}
Output of this application:
44
K5NtMqCN7IuYjzccr1bAdajtfiyKD2xL15Eyg5oFCOc=
If I am not mistaken, the output should be:
64
2b936d32a08dec8b988f371caf56c075a8ed7e2c8a0f6c4b979132839a0508e7
What is going on here?
See where it says Convert.ToBase64String(hashedBytes)
? It's not giving you a hexadecimal string (4 bits per character) - it's in base 64 (6 bits per character).
You're converting it to a Base64 string...
You might want to use this instead:
// Cut bad code
Edit: which once again is a poor man's implementation of the BitConverter.ToString() posted above. Why is the internet filled with reimplementations of existing framework functionality when searching for common functionality like "string to hex"? ;-(
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