Token cache

[sreeise]

Token cache for storing OAuth tokens and support for eviction policies.

All Platforms and all Application Types

• All platforms at the base level will be supported by an internal memory cache.
• Azure Key Vault

Desktops

The implementation will be different across platforms. The goal is to support Linux (Debian/Ubuntu based distros), Windows, and MacOS.

Documentation or relevant references:

• https://github.com/AzureAD/microsoft-authentication-extensions-for-dotnet/blob/main/src/Microsoft.Identity.Client.Extensions.Msal/Cache%20Architecture.png
• https://github.com/AzureAD/microsoft-authentication-extensions-for-dotnet/wiki/Cross-platform-Token-Cache#encryption-and-storage

Some of these will be dependent upon support for these use cases in Rust such as the Windows api's.

On Windows:

• Using DPAPI: https://learn.microsoft.com/en-us/dotnet/standard/security/how-to-use-data-protection

The Rust Windows crate has an example using data-protection: https://github.com/microsoft/windows-rs/blob/0.48.0/crates/samples/windows/data_protection/src/main.rs

On MacOS:

• Using MacOS KeyChain

Linux

• Using Linux Libsecret

Ticket Progress

• In Memory Token Cache - Part of pre-release 2.0.0-beta.0 and 2.0.0
• Azure Key Vault - Token Cache - Azure Key Vault #474 - 2.1.0
• Desktop - Windows DPAPI - Token Cache - Windows DPAPI (Desktop) #475 - 2.2.0
• Desktop - MacOS KeyChain Token Cache - Desktop - MacOS KeyChain #476 - 2.2.0
• Desktop - Linux KeyRing Token Cache - Desktop - Linux Libsecret #477 - - 2.2.0