EdDsa and Curve25519 keys in C#

DidiSoft OpenPGP Library for .NET version 1.9.3 offers support for the creation of Elliptic Curve Cryptography (ECC) PGP keys based on Curve-25519.

What is Curve-25519?

Curve-25519  is one of the fastest ECC curves and is not covered by any known attack patents.

The first Elliptic Curves introduced in OpenPGP standard were the NIST curves. Their first alternative was the set of Brainpool curves that unfortunately suffered in performance.

Curve-25519 comes as a higher speed, high-security alternative to the NIST curves.

Creating a Curve-25519 key pair

The example below will create an OpenPGP key pair with a master key based on EdDsa over Curve 25519 and an encryption subkey based on Elliptic Curve Diffie-Hellman (ECDH) over Curve-25519.

C# example

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using System;
using DidiSoft.Pgp;
 
public class GenerateEccKeyPairDemo
{
   public void Demo()			
   {
       KeyStore ks = new KeyStore();
 
       // EC curve for this key   
       EcCurve curve = EcCurve.Curve25519;
       // primary User Id of the key
       string userId = "Demo <demo@didisoft.com>";
       // password for the private key
       string privateKeyPassword = "changeit";
 
       KeyPairInformation newKey = ks.GenerateEccKeyPair(curve, userId, privateKeyPassword);
   }
}

VB.NET example

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Imports System
Imports DidiSoft.Pgp
 
Public Class GenerateEccKeyPairDemo
   Public Sub Test()
       Dim ks As New KeyStore()
 
       '  EC curve for this key
       Dim curve As EcCurve = EcCurve.Curve25519
       ' primary User Id of the key
       Dim userId As String = "Demo <demo@didisoft.com>"
       ' password for the private key
       Dim privateKeyPassword As String = "changeit"
 
       Dim newKey As KeyPairInformation = ks.GenerateEccKeyPair(curve, userId, privateKeyPassword)
   End Sub
End Class

 

Curve-22519 cryptography operations

Cryptography operations with keys based on Curve-22519 are available transparently without any need for code modifications.