.NET Core Crypto Extensions

Konscious.Security.Cryptography.Blake2

NuGet package

An implementation of Blake2 per RFC 7693 in C# and available for .NET core

https://blake2.net/

Usage follows standard types found in System.Security.Cryptography in corefx. Specifically HMAC algorithms.

Usage

You can use Blake2B interchangeably with any code that uses System.Security.Cryptography.HashAlgorithm Or System.Security.Cryptography.HMAC And usage is generally consistent with both.

In the project.json:

"dependencies":
{
  "Konscious.Security.Cryptography.Blake2": "1.0.*"
}

Create an instance of the algorithm:

using Konscious.Security.Cryptography;

var hashAlgorithm = new Blake2B(512);

This will give you a default implementation with no salt that generates a 512 bit key

byte[] key = ...
var hashAlgorithm = new Blake2B(key, 512);

This will specify some salt to use for the 512 bit hash. Hash size can be any 8 bit aligned value between 8 and 512. The key can be any size between 0 and 64 bytes.

The algorithm needs to be initialized before use:

hashAlgorithm.Initialize();

Then it can be used with any of the standard HashAlgorithm overloads

Stream p = ...
hashAlgorithm.Hash(p);

byte[] a = ...
hashAlgorithm.Hash(a);

And as consistent with any other HMAC implementation:

hashAlgorithm.Key = otherByteArray;

Konscious.Security.Cryptography.Argon2

NuGet package

An implementation of Argon2 winner of PHC

https://password-hashing.net/#argon2

Usage follows standard types found in System.Security.Cryptography in corefx. Specifically DeriveBytes.

Usage

There is both an Argon2i and Argon2d implementation included in this library. Argon2d is less intensive but subject to timing attacks. That is, if an attacker is appropriately positioned, they can observe the nanosecond differences in processing keys to perform a non-naive brute force attack to reverse the key. Argon2i is non-deterministic so there is no way for an attacker to deduce qualities of the password even if they can observe individual clock cycles and is thus more secure where timing attacks are possible.

Both are standard implementations of the System.Security.Cryptography.DeriveBytes type from corefx. This is commonly used for less secure password hashing via System.Security.Cryptography.Rfc2898DeriveBytes which implements the standard PBKDF2 scheme. Argon2 provides a more secure alternative for password hashing.

Project.json:

  "dependencies":
  {
      "Konscious.Security.Cryptography.Argon2": "1.0.*"
  }

As with Rfc2898DeriveBytes, an Argon2 object is constructed with the password to be hashed:

using Konscious.Security.Cryptography;

byte[] password = ...
var argon2 = new Argon2i(password);

or

var argon2 = new Argon2d(password);

or

var argon2 = new Argon2id(password);

Various attributes can be added to secure the hash:

And the primary hash method:

byte[] GetBytes(int)

Which takes the number of bytes to generate. This implementation will accept only up to 1024 bytes as input.

byte[] salt;
byte[] userUuidBytes;
...
argon2.DegreeOfParallelism = 16;
argon2.MemorySize = 8192;
argon2.Iterations = 40;
argon2.Salt = salt;
argon2.AssociatedData = userUuidBytes;

var hash = argon2.GetBytes(128);