fix(e2ee): propagate worker decryption errors and reject corresponding promises (#1729)

Co-authored-by: lukasIO <mail@lukasseiler.de>

Author: CSantosM

.changeset/gorgeous-llamas-whisper.md

@@ -0,0 +1,5 @@
+---
+"livekit-client": patch
+---
+
+fix(e2ee): propagate worker data decryption errors and reject corresponding promises

src/e2ee/E2eeManager.ts

@@ -144,6 +144,24 @@ export class E2EEManager
     switch (kind) {
       case 'error':
         log.error(data.error.message);
+
+        // If error has uuid, it's from an async operation (encrypt/decrypt)
+        // Reject the corresponding future
+        if (data.uuid) {
+          const decryptFuture = this.decryptDataRequests.get(data.uuid);
+          if (decryptFuture?.reject) {
+            decryptFuture.reject(data.error);
+            break; // Don't emit general error if it's handled by future
+          }
+
+          const encryptFuture = this.encryptDataRequests.get(data.uuid);
+          if (encryptFuture?.reject) {
+            encryptFuture.reject(data.error);
+            break; // Don't emit general error if it's handled by future
+          }
+        }
+
+        // Emit general error event for unhandled errors
         this.emit(EncryptionEvent.EncryptionError, data.error, data.participantIdentity);
         break;
       case 'initAck':

src/e2ee/types.ts

@@ -92,6 +92,7 @@ export interface ErrorMessage extends BaseMessage {
   data: {
     error: Error;
     participantIdentity?: string;
+    uuid?: string; // Optional: used for async operation errors (decrypt/encrypt)
   };
 }
 

src/e2ee/worker/e2ee.worker.ts

@@ -111,21 +111,32 @@ onmessage = (ev) => {
         break;
 
       case 'decryptDataRequest':
-        const { payload: decryptedPayload } = await DataCryptor.decrypt(
-          data.payload,
-          data.iv,
-          getParticipantKeyHandler(data.participantIdentity),
-          data.keyIndex,
-        );
-        console.log('decrypted payload', {
-          original: data.payload,
-          decrypted: decryptedPayload,
-          iv: data.iv,
-        });
-        postMessage({
-          kind: 'decryptDataResponse',
-          data: { payload: decryptedPayload, uuid: data.uuid },
-        } satisfies DecryptDataResponseMessage);
+        try {
+          const { payload: decryptedPayload } = await DataCryptor.decrypt(
+            data.payload,
+            data.iv,
+            getParticipantKeyHandler(data.participantIdentity),
+            data.keyIndex,
+          );
+          postMessage({
+            kind: 'decryptDataResponse',
+            data: { payload: decryptedPayload, uuid: data.uuid },
+          } satisfies DecryptDataResponseMessage);
+        } catch (error) {
+          // Send error back to main thread with uuid so it can reject the corresponding promise
+          workerLogger.error('DataCryptor decryption failed', {
+            error,
+            participantIdentity: data.participantIdentity,
+            uuid: data.uuid,
+          });
+          postMessage({
+            kind: 'error',
+            data: {
+              error: error instanceof Error ? error : new Error(String(error)),
+              uuid: data.uuid, // Include uuid to match with the pending request
+            },
+          } satisfies ErrorMessage);
+        }
         break;
 
       case 'setKey':