EchoHub/docs/auriondocs/Code/src/EchoHub.Client/Services/RoomKeyStore.cs.md

RoomKeyStore

File: src/EchoHub.Client/Services/RoomKeyStore.cs
Kind: class

public sealed class RoomKeyStore

Holds and manages room content keys for end-to-end encrypted channels for the active session and the persisted per-server client configuration. Use RoomKeyStore when you need a single place to cache decrypted room keys in memory, persist them encrypted to the local config (so users don't retype passphrases on each launch), and track which channels are known to be end-to-end encrypted.

Remarks

RoomKeyStore is the in-process authority for room keys: it keeps a memory cache (_keys) for the running session and a set (_encryptedChannels) to mark channels that are treated as encrypted. It delegates on-disk protection to RoomKeyProtector so keys never leave the machine in plaintext. Calling LoadForServer binds the store to a specific server URL, loads that server's SavedServer.ChannelKeys via ConfigManager.Load(), and hydates the in-memory cache (skipping unreadable entries). Legacy plaintext/legacy-storage entries detected by RoomKeyProtector.TryUnprotect are re-encrypted and re-persisted as a one-way upgrade. All public mutation and lookup methods synchronize on the internal Lock (_lock) to provide basic thread-safety for concurrent callers.

Notes

• TryGetKey returns the stored byte array reference from the internal _keys map (no defensive copy). Callers must not mutate the returned byte[] in-place — clone it first if modification is required.
• Channel name lookup is case-insensitive because the internal collections use StringComparer.OrdinalIgnoreCase. Treat channel names consistently to avoid duplicate/lookup surprises.
• Loading ignores unreadable cached entries and will re-persist only entries that RoomKeyProtector could successfully unprotect; TryStoreFromEnvelope returns false when the provided KEK fails to unwrap the envelope and will leave the cache unchanged. Storing or removing a key persists the corresponding SavedServer.ChannelKeys entry immediately (via the store's persistence path).