Hashing a password using SHA256 and .NET/Node.js

Question

Im Storing SHA256 hashes of user passwords in my database generated by .NET and I need to be able to check them with Node.js. The only problem is that .NET and Node.js create different hashes for the same password.

Password: ThisPassword  

.NET:

var ue = new UnicodeEncoding();  
var byteSourceText = ue.GetBytes("ThisPassword");  
var byteHash = new System.Security.Cryptography.SHA256Managed().ComputeHash(byteSourceText);  
return Convert.ToBase64String(byteHash);

//Tlwxyd7HIQhXkN6DrWJtmB9Ag2fz84P/QgMtbi9XS6Q=

Node.js (Using Crypto):

var crypto = require('crypto');
return crypto.createHash('sha256').update('ThisPassword').digest('base64')

//d7I986+YD1zS6Wz2XAcDv2K8yw3xIVUp7u/OZiDzhSY=

I found this, but was unable to figure out how to implement his solution.

Answer 1

Edit: You are using UTF-16 in C#, you must use same encoding in both languages:

Node.js:

var crypto = require("crypto");
var sha256 = crypto.createHash("sha256");
sha256.update("ThisPassword", "utf8");//utf8 here
var result = sha256.digest("base64");
console.log(result); //d7I986+YD1zS6Wz2XAcDv2K8yw3xIVUp7u/OZiDzhSY=

C#:

SHA256 sha256 = SHA256Managed.Create(); //utf8 here as well
byte[] bytes = sha256.ComputeHash(Encoding.UTF8.GetBytes("ThisPassword"));
string result = Convert.ToBase64String(bytes);
Console.WriteLine(result); //d7I986+YD1zS6Wz2XAcDv2K8yw3xIVUp7u/OZiDzhSY=

Answer 2

If you're using the .NET Framework's built-in SqlMembershipProvider Class from System.Web.Security, the hash incorporates a salt value as well as the password material when it is generated. Simply hashing the password alone in your node.js will never produce the same result as the hash in the database.

See Microsoft ASP.NET 2.0 Providers: Introduction for a link to .NET source code for the provider that will let you see how the salt value is applied.

You need to include your code if you need more help than this.