Fix encryption: support direct RSA-OAEP and hybrid RSA+AES-GCM modes

encryption.py

@@ -188,32 +188,29 @@ def decrypt_multiple_blocks(encrypted_data: str) -> list[Any]:
     """
     Decrypt multiple concatenated encrypted blocks.
     
-    Each block is a complete base64 JSON payload. Since blocks can vary in size,
-    we need to find block boundaries by looking for valid JSON structures.
+    The input is expected to be a comma-separated list of base64 strings.
     
     Args:
-        encrypted_data: Concatenated base64-encoded encrypted blocks
+        encrypted_data: Comma-separated base64-encoded encrypted blocks
         
     Returns:
         List of decrypted data objects
     """
     results = []
     
-    # If it looks like a single block (starts with valid base64 for JSON)
-    # Try single block first
-    if encrypted_data:
-        result = decrypt_data(encrypted_data)
-        if result and "decryption_error" not in result:
-            results.append(result)
-            return results
-    
-    # If single block fails, the data might be multiple blocks
-    # Since each block is base64(JSON), we need to find block boundaries
-    # Common approach: try to find where one base64 ends and another begins
-    # For now, store the error result from single attempt
-    if not results:
-        result = decrypt_data(encrypted_data)
-        if result:
-            results.append(result)
-    
+    if not encrypted_data:
+        return results
+        
+    # Split by comma to separate blocks
+    # Base64 does not use commas, so this is safe
+    blocks = encrypted_data.split(',')
+    
+    for block in blocks:
+        block = block.strip()
+        if not block:
+            continue
+            
+        result = decrypt_data(block)
+        results.append(result)
+            
     return results