Where is Asp.Net Core source code for EphemeralKeyRing Class? - security

Question

Was EphemeralKeyRing omitted from GitHub for Security Reasons?
This one is a brain teaser. I've spent quite a bit of time lately reading and and absorbing the hierarchy of classes that relate to asp.net core session storage and asp.net core data protection. In those journeys, I have come across a reference to a EphemeralKeyRing class. However, the code for this class does not seem to be in the Asp.Net Core source code repository on GitHub. Equally odd, when doing a google search on this class name, I can find no references anywhere on the internet that are about this asp.net core class other than the one GitHub source code file that uses it.
Here is the class that news up a EphemeralKeyRing object: https://github.com/aspnet/DataProtection/blob/rel/1.1.0/src/Microsoft.AspNetCore.DataProtection/EphemeralDataProtectionProvider.cs
Here's the results of a GitHub search for the EphemeralKeyRing class in the Asp.Net Core repository:
:
And here is the an amazingly sparse set of google results when searching for EphemeralKeyRing. Note the first entry is the code file on GitHub that I mentioned above which uses the object and the other results are unrelated to this asp.net core class.
So my question is this: Was the source code for the EphemeralKeyRing class omitted from GitHub purposely for security reasons? Or is it there and I'm just searching wrong?

Answer 1

Here is the link:
https://github.com/aspnet/DataProtection/blob/master/src/Microsoft.AspNetCore.DataProtection/EphemeralDataProtectionProvider.cs
which I see you found and clicked on it already. If you go to the bottom of the page youll see the class you are looking for, I'll paste the code just in case:
private sealed class EphemeralKeyRing<T> : IKeyRing, IKeyRingProvider
where T : IInternalAuthenticatedEncryptionSettings, new()
{
// Currently hardcoded to a 512-bit KDK.
private const int NUM_BYTES_IN_KDK = 512 / 8;
public IAuthenticatedEncryptor DefaultAuthenticatedEncryptor { get; } = new T().ToConfiguration(services: null).CreateNewDescriptor().CreateEncryptorInstance();
public Guid DefaultKeyId { get; } = default(Guid);
public IAuthenticatedEncryptor GetAuthenticatedEncryptorByKeyId(Guid keyId, out bool isRevoked)
{
isRevoked = false;
return (keyId == default(Guid)) ? DefaultAuthenticatedEncryptor : null;
}
public IKeyRing GetCurrentKeyRing()
{
return this;
}
}