base: Properly handle crypto related errors in the sled store

matrix_sdk_base/src/store/mod.rs

@@ -25,8 +25,6 @@ use matrix_sdk_common::{
     locks::RwLock,
 };
 
-use sled::transaction::TransactionError;
-
 use crate::{
     deserialized_responses::{MemberEvent, StrippedMemberEvent},
     rooms::{RoomInfo, RoomType, StrippedRoom},
@@ -44,15 +42,12 @@ pub enum StoreError {
     Json(#[from] serde_json::Error),
     #[error(transparent)]
     Identifier(#[from] matrix_sdk_common::identifiers::Error),
-}
-
-impl From<TransactionError<serde_json::Error>> for StoreError {
-    fn from(e: TransactionError<serde_json::Error>) -> Self {
-        match e {
-            TransactionError::Abort(e) => Self::Json(e),
-            TransactionError::Storage(e) => Self::Sled(e),
-        }
-    }
+    #[error("The store failed to be unlocked")]
+    StoreLocked,
+    #[error("The store is not encrypted but was tried to be opened with a passphrase")]
+    UnencryptedStore,
+    #[error("Error encrypting or decrypting data from the store: {0}")]
+    Encryption(String),
 }
 
 /// A `StateStore` specific result type.

matrix_sdk_base/src/store/sled_store/mod.rs

@@ -45,6 +45,35 @@ pub enum DatabaseType {
     Encrypted(store_key::EncryptedStoreKey),
 }
 
+#[derive(Debug, thiserror::Error)]
+pub enum SerializationError {
+    #[error(transparent)]
+    Json(#[from] serde_json::Error),
+    #[error(transparent)]
+    Encryption(#[from] store_key::Error),
+}
+
+impl From<TransactionError<SerializationError>> for StoreError {
+    fn from(e: TransactionError<SerializationError>) -> Self {
+        match e {
+            TransactionError::Abort(e) => e.into(),
+            TransactionError::Storage(e) => StoreError::Sled(e),
+        }
+    }
+}
+
+impl From<SerializationError> for StoreError {
+    fn from(e: SerializationError) -> Self {
+        match e {
+            SerializationError::Json(e) => StoreError::Json(e),
+            SerializationError::Encryption(e) => match e {
+                store_key::Error::Serialization(e) => StoreError::Json(e),
+                store_key::Error::Encryption(e) => StoreError::Encryption(e),
+            },
+        }
+    }
+}
+
 #[derive(Debug, Clone)]
 pub struct SledStore {
     inner: Db,
@@ -119,10 +148,9 @@ impl SledStore {
 
         let store_key = if let Some(key) = store_key {
             if let DatabaseType::Encrypted(k) = key {
-                let key = StoreKey::import(passphrase, k).unwrap();
-                key
+                StoreKey::import(passphrase, k).map_err(|_| StoreError::StoreLocked)?
             } else {
-                panic!("Trying to open an unencrypted store with a passphrase");
+                return Err(StoreError::UnencryptedStore);
             }
         } else {
             let key = StoreKey::new();
@@ -144,24 +172,24 @@ impl SledStore {
     fn serialize_event(
         &self,
         event: &impl Serialize,
-    ) -> std::result::Result<Vec<u8>, serde_json::Error> {
+    ) -> std::result::Result<Vec<u8>, SerializationError> {
         if let Some(key) = &*self.store_key {
-            let encrypted = key.encrypt(event).unwrap();
-            serde_json::to_vec(&encrypted)
+            let encrypted = key.encrypt(event)?;
+            Ok(serde_json::to_vec(&encrypted)?)
         } else {
-            serde_json::to_vec(event)
+            Ok(serde_json::to_vec(event)?)
         }
     }
 
     fn deserialize_event<T: for<'b> Deserialize<'b>>(
         &self,
         event: &[u8],
-    ) -> std::result::Result<T, serde_json::Error> {
+    ) -> std::result::Result<T, SerializationError> {
         if let Some(key) = &*self.store_key {
             let encrypted: EncryptedEvent = serde_json::from_slice(&event)?;
-            Ok(key.decrypt(encrypted).unwrap())
+            Ok(key.decrypt(encrypted)?)
         } else {
-            serde_json::from_slice(event)
+            Ok(serde_json::from_slice(event)?)
         }
     }
 
@@ -189,7 +217,7 @@ impl SledStore {
     pub async fn save_changes(&self, changes: &StateChanges) -> Result<()> {
         let now = SystemTime::now();
 
-        let ret: std::result::Result<(), TransactionError<serde_json::Error>> = (
+        let ret: std::result::Result<(), TransactionError<SerializationError>> = (
             &self.session,
             &self.account_data,
             &self.members,
@@ -440,7 +468,7 @@ impl SledStore {
         stream::iter(
             self.room_info
                 .iter()
-                .map(move |r| db.deserialize_event(&r?.1).map_err(StoreError::Json)),
+                .map(move |r| db.deserialize_event(&r?.1).map_err(|e| e.into())),
         )
     }
 }

matrix_sdk_base/src/store/sled_store/store_key.rs

@@ -44,8 +44,6 @@ pub enum Error {
     Serialization(#[from] serde_json::Error),
     #[error("Error encrypting or decrypting an event {0}")]
     Encryption(String),
-    #[error("Unknown ciphertext version")]
-    InvalidVersion,
 }
 
 impl From<EncryptionError> for Error {
@@ -129,6 +127,7 @@ impl StoreKey {
         Default::default()
     }
 
+    /// Expand the given passphrase into a KEY_SIZE long key.
     fn expand_key(passphrase: &str, salt: &[u8], rounds: u32) -> Zeroizing<Vec<u8>> {
         let mut key = Zeroizing::from(vec![0u8; KEY_SIZE]);
         pbkdf2::<Hmac<Sha256>>(passphrase.as_bytes(), &salt, rounds, &mut *key);
@@ -172,7 +171,7 @@ impl StoreKey {
 
     fn get_nonce() -> Vec<u8> {
         let mut nonce = vec![0u8; XNONCE_SIZE];
-        getrandom(&mut nonce).expect("Can't generate nonce");
+        getrandom(&mut nonce).expect("Can't get random nonce");
         nonce
     }
 
@@ -194,7 +193,9 @@ impl StoreKey {
 
     pub fn decrypt<T: for<'b> Deserialize<'b>>(&self, event: EncryptedEvent) -> Result<T, Error> {
         if event.version != VERSION {
-            return Err(Error::InvalidVersion);
+            return Err(Error::Encryption(
+                "Error decrypting: Unknown ciphertext version".to_string(),
+            ));
         }
 
         let cipher = XChaCha20Poly1305::new(self.key());