There are multiple ways of generating an encryption key. Most implementations rely on a random object. All examples mentioned here use a secure cryptographic randomizer.
PowerShell
Base64
Add-Type -AssemblyName System.Security
[Reflection.Assembly]::LoadWithPartialName("System.Security")
$rijndael = new-Object System.Security.Cryptography.RijndaelManaged
$rijndael.GenerateKey()
Write-Host([Convert]::ToBase64String($rijndael.Key))
$rijndael.Dispose()
Hex
Add-Type -AssemblyName System.Security
[Reflection.Assembly]::LoadWithPartialName("System.Security")
$rijndael = new-Object System.Security.Cryptography.RijndaelManaged
$rijndael.GenerateKey()
Write-Host([System.BitConverter]::ToString($rijndael.Key).Replace("-", "").ToLowerInvariant())
$rijndael.Dispose()
C#
The code snippets below can be run from LINQPad or by copying the following code into a new project and referencing System..
Base64
using (var rijndael = System.Security.Cryptography.Rijndael.Create())
{
rijndael.GenerateKey();
var key = Convert.ToBase64String(rijndael.Key);
Console.WriteLine(key);
}
Hex
using (var rijndael = System.Security.Cryptography.Rijndael.Create())
{
rijndael.GenerateKey();
var key = BitConverter.ToString(rijndael.Key)
.Replace("-", string.Empty)
.ToLowerInvariant();
Console.WriteLine(key);
}
OpenSSL
OpenSSL is well known for its ability to generate certificates but it can also be used to generate random data.
Base64
Generates 32 random bytes (256bits) in a base64 encoded output:
openssl rand -base64 32
Plaintext
Generates 32 random characters (256bits):
openssl rand 32
Be aware that strings parsed by NServiceBus do not use extended ASCII which limits the key range to 7 bits per character.