What is the equivalent to PersistKeysToDbContext in ASP.NET 4.6?

Question

I am attempting to share my authentication Cookies between a ASP.NET Core application and a ASP.NET 4.X application.

I am following this tutorial: Share authentication cookies among ASP.NET apps . However I am stuck because our .NET Core application uses the PersistKeysToDbContext to share the Cookie keys:

 services.AddDataProtection()
       .SetApplicationName("MyApplicationName")
       .PersistKeysToDbContext<MyDatabaseContext>();

And, as per the tutorial, I will use the following code in my .NET 4.6 application:

app.UseCookieAuthentication(new CookieAuthenticationOptions
{
    AuthenticationType = "Identity.Application",
    CookieName = ".AspNet.SharedCookie",
    LoginPath = new PathString("/Account/Login"),
    Provider = new CookieAuthenticationProvider
    {
        OnValidateIdentity =
            SecurityStampValidator
                .OnValidateIdentity<ApplicationUserManager, ApplicationUser>(
                    validateInterval: TimeSpan.FromMinutes(30),
                    regenerateIdentity: (manager, user) =>
                        user.GenerateUserIdentityAsync(manager))
    },
    TicketDataFormat = new AspNetTicketDataFormat(
        new DataProtectorShim(
            DataProtectionProvider.Create("{PATH TO COMMON KEY RING FOLDER}",
                (builder) => { builder.SetApplicationName("SharedCookieApp"); })
            .CreateProtector(
                "Microsoft.AspNetCore.Authentication.Cookies." +
                    "CookieAuthenticationMiddleware",
                "Identity.Application",
                "v2"))),
    CookieManager = new ChunkingCookieManager()
});

The DataProtectionProvider.Create does not seem to allow for either database storage or for custom storage. I am completely stuck - how do I use SQL server to share the keys from .NET Core to .NET 4.6?

Answer 1

In the end I did find the solution. I implemented my own version of PersistKeysToDbContext . Now the code for "TicketDataFormat" (in Startup.Auth.cs) looks like this:

    TicketDataFormat = new AspNetTicketDataFormat(
                new DataProtectorShim(
                        DataProtectionProvider.Create(
                            new DirectoryInfo("{PATH TO COMMON KEY RING FOLDER}"),
                            (builder) => { 
                                builder.SetApplicationName("SharedCookieApp");
                                builder.Services.AddSingleton<IConfigureOptions<KeyManagementOptions>>(services =>
                                {
                                    return new ConfigureOptions<KeyManagementOptions>(options =>
                                    {
                                        options.XmlRepository = new MyXmlRepository();
                                    });
                                });
                         }).CreateProtector(
                        "Microsoft.AspNetCore.Authentication.Cookies." +
                            "CookieAuthenticationMiddleware",
                        "Cookies",
                        "v2"))),

You must now implement a class that reads and writes to the database, which must implement the interface Microsoft.AspNetCore.DataProtection.Repositories.IXmlRepository :

public class MyXmlRepository : IXmlRepository
{

    public virtual IReadOnlyCollection<XElement> GetAllElements()
    {
        // This function must return a list of all the elements in the database
    }

    public void StoreElement(XElement element, string friendlyName)
    {
        // This function must write to the database (this is optional if this
        // service never provides the authentication, only uses it)
    }
}