keymgr: Make Keystore::generate() return a Result.

crates/tor-keymgr/src/keystore.rs

@@ -83,7 +83,7 @@ pub trait EncodableKey: Downcast {
         Self: Sized;
 
     /// Generate a new key of this type.
-    fn generate(rng: &mut dyn KeygenRng) -> Self
+    fn generate(rng: &mut dyn KeygenRng) -> Result<Self>
     where
         Self: Sized;
 
@@ -101,11 +101,11 @@ impl EncodableKey for curve25519::StaticSecret {
         KeyType::X25519StaticSecret
     }
 
-    fn generate(rng: &mut dyn KeygenRng) -> Self
+    fn generate(rng: &mut dyn KeygenRng) -> Result<Self>
     where
         Self: Sized,
     {
-        curve25519::StaticSecret::new(rng)
+        Ok(curve25519::StaticSecret::new(rng))
     }
 
     fn to_bytes(&self) -> Result<Zeroizing<Vec<u8>>> {
@@ -121,13 +121,13 @@ impl EncodableKey for ed25519::Keypair {
         KeyType::Ed25519Keypair
     }
 
-    fn generate(rng: &mut dyn KeygenRng) -> Self
+    fn generate(rng: &mut dyn KeygenRng) -> Result<Self>
     where
         Self: Sized,
     {
         use tor_llcrypto::util::rand_compat::RngCompatExt;
 
-        ed25519::Keypair::generate(&mut rng.rng_compat())
+        Ok(ed25519::Keypair::generate(&mut rng.rng_compat()))
     }
 
     fn to_bytes(&self) -> Result<Zeroizing<Vec<u8>>> {

crates/tor-keymgr/src/mgr.rs

@@ -61,7 +61,7 @@ impl KeyMgr {
         let key_type = K::Key::key_type();
 
         if overwrite || !store.contains(key_spec, key_type)? {
-            let key = K::Key::generate(rng);
+            let key = K::Key::generate(rng)?;
             store.insert(&key, key_spec, key_type)
         } else {
             Ok(())
@@ -189,11 +189,11 @@ mod tests {
             KeyType::Ed25519Keypair
         }
 
-        fn generate(_rng: &mut dyn KeygenRng) -> Self
+        fn generate(_rng: &mut dyn KeygenRng) -> Result<Self>
         where
             Self: Sized,
         {
-            "generated_test_key".into()
+            Ok("generated_test_key".into())
         }
 
         fn to_bytes(&self) -> Result<zeroize::Zeroizing<Vec<u8>>> {