Fix file encryption

Signed-off-by: Tiago Garcia <tiago.rgarcia@ua.pt>

delivery2/client/bin/rep_add_doc

@@ -51,10 +51,10 @@ def addDoc(args):
         args.session = json.load(f)
 
     #Encrypt content
-    key, content, nonce = encrypt_file(BASE_DIR + args.file, BASE_DIR + 'encryptedText')
+    key, content = encrypt_file(BASE_DIR + args.file, BASE_DIR + 'encryptedText')
 
     #Upload document metadata
-    doc = {'document_name' : args.name, 'key' : key.hex(), 'alg' : 'AES-CFB', 'nonce' : nonce.hex() }
+    doc = {'document_name' : args.name, 'key' : key.hex(), 'alg' : 'AES-CFB' }
     
     try:
         req = requests.post(f'http://{state['REP_ADDRESS']}/file/upload/metadata', json=json.dumps(doc),

delivery2/lib/symmetric_encryption.py

@@ -6,41 +6,49 @@ from cryptography.hazmat.backends import default_backend
 
 # Function to encrypt a file using a salt
 def encrypt_file(input_file, output_file=None):
-	key = os.urandom(16)
-	iv = os.urandom(16)
+    key = os.urandom(16)
+    iv = os.urandom(16)
 
-	cipher = Cipher(algorithms.AES(key), modes.CFB(iv))
-	encryptor = cipher.encryptor()
+    cipher = Cipher(algorithms.AES(key), modes.CFB(iv))
+    encryptor = cipher.encryptor()
 
-	with open(input_file, 'rb') as f:
-		plaintext = f.read()
+    encrypted_content = b""
 
-	ciphertext = encryptor.update(plaintext) + encryptor.finalize()
-	ciphertext = iv + ciphertext
+    if output_file is not None:
+        with open(input_file, 'rb') as infile, open(output_file, 'wb') as outfile:
+            # Write the IV to the output file first
+            outfile.write(iv)
+            encrypted_content += iv
 
-	if output_file is not None:
-		with open(output_file, 'wb') as f:
-			f.write(ciphertext)
+            while chunk := infile.read(2048):
+                ciphertext = encryptor.update(chunk)
+                outfile.write(ciphertext)
+                encrypted_content += ciphertext
 
-	print(iv.hex())
+            # Finalize encryption
+            final_chunk = encryptor.finalize()
+            outfile.write(final_chunk)
+            encrypted_content += final_chunk
 
-	return key, ciphertext, iv
+    return key, encrypted_content
 
 
 # Function to decrypt a file
-def decrypt_file(nonce, key, input_file, output_file=None):
-	with open(input_file, 'rb') as f:
-		encrypted_data = f.read()
+def decrypt_file(key, input_file, output_file=None):
+    with open(input_file, 'rb') as infile:
+        # Read the IV from the input file
+        iv = infile.read(16)
+        cipher = Cipher(algorithms.AES(key), modes.CFB(iv))
+        decryptor = cipher.decryptor()
 
-	ciphertext = encrypted_data
+        if output_file is not None:
+            with open(output_file, 'wb') as outfile:
+                while chunk := infile.read(2048):
+                    plaintext = decryptor.update(chunk)
+                    outfile.write(plaintext)
 
-	cipher = Cipher(algorithms.AES(key), modes.CFB(nonce))
-	decryptor = cipher.decryptor()
+                # Finalize decryption
+                outfile.write(decryptor.finalize())
 
-	plaintext = decryptor.update(ciphertext) + decryptor.finalize()
+    return True
 
-	if output_file is not None:
-		with open(output_file, 'wb') as f:
-			f.write(plaintext)
-
-	return plaintext.hex()

delivery2/server/models/file.py

@@ -11,7 +11,6 @@ class File(db_connection.Model):
     created_at = db_connection.Column(db_connection.Integer, nullable=False)
     key = db_connection.Column(db_connection.String, nullable=False)
     alg = db_connection.Column(db_connection.String, nullable=False)
-    nonce = db_connection.Column(db_connection.String, nullable=False)
     org_id = db_connection.Column(db_connection.Integer, db_connection.ForeignKey('organizations.id'), nullable=False)
     creator_id = db_connection.Column(db_connection.Integer, db_connection.ForeignKey('users.id'), nullable=False)
     org = db_connection.relationship('Organization', backref=db_connection.backref('org_files', uselist=False))
@@ -26,7 +25,6 @@ class File(db_connection.Model):
             "created_at": self.created_at,
             "key": self.key,
             "alg": self.alg,
-            "nonce": self.nonce,
             "org": {"id": self.org.id, "name": self.org.name},
             "creator": {"id": self.creator.id, "username": self.creator.username}
         }

delivery2/server/routes/file.py

@@ -48,7 +48,7 @@ def file_upload_metadata():
     data = request.json
     if type(data) is str:
         data = json.loads(data)
-    if "document_name" not in data or "key" not in data or "alg" not in data or "nonce" not in data:
+    if "document_name" not in data or "key" not in data or "alg" not in data:
         return jsonify({"error": "Missing required fields"}), 400
 
     org = OrganizationService.get_organization(session.org_id)
@@ -59,7 +59,7 @@ def file_upload_metadata():
     if not user:
         return jsonify({"error": "User not found"}), 404
 
-    file = upload_service.create_file(session.token, org, user, data["document_name"], data["key"], data["alg"], data["nonce"])
+    file = upload_service.create_file(session.token, org, user, data["document_name"], data["key"], data["alg"])
     return jsonify(file.to_dict()), 201
 
 

delivery2/server/services/files.py

@@ -13,7 +13,7 @@ class FileService:
     def __init__(self):
         self.current_requests = {}
 
-    def create_file(self, session_token: str, org: Organization, user: User, file_name: str, key: str, alg: str, nonce: str) -> File:
+    def create_file(self, session_token: str, org: Organization, user: User, file_name: str, key: str, alg: str) -> File:
         file = File(
             file_handle = None,
             document_handle = get_hash(file_name),
@@ -21,7 +21,6 @@ class FileService:
             created_at = int(datetime.now().timestamp()),
             key = key,
             alg = alg,
-            nonce = nonce,
             org_id = org.id,
             creator_id = user.id,
             org = org,