Use indirection to implement the default KeyStore

src/env/tock/mod.rs

@@ -16,6 +16,7 @@ pub use self::storage::{TockStorage, TockUpgradeStorage};
 use crate::api::connection::{HidConnection, SendOrRecvError, SendOrRecvResult, SendOrRecvStatus};
 use crate::api::customization::{CustomizationImpl, DEFAULT_CUSTOMIZATION};
 use crate::api::firmware_protection::FirmwareProtection;
+use crate::api::key_store;
 use crate::api::user_presence::{UserPresence, UserPresenceError, UserPresenceResult};
 use crate::clock::{ClockInt, KEEPALIVE_DELAY_MS};
 use crate::env::Env;
@@ -193,6 +194,8 @@ impl FirmwareProtection for TockEnv {
     }
 }
 
+impl key_store::Helper for TockEnv {}
+
 impl Env for TockEnv {
     type Rng = TockRng256;
     type UserPresence = Self;