diff --git a/lib_cryptomator_utils/aes.py b/lib_cryptomator_utils/aes.py
index 7f8def9..4b2b205 100644
--- a/lib_cryptomator_utils/aes.py
+++ b/lib_cryptomator_utils/aes.py
@@ -1,5 +1,5 @@
 #   cryptomator-utils: Python utilities for inspecting Cryptomator drives
-#   Copyright (C) 2024  Lee Yingtong Li (RunasSudo)
+#   Copyright (C) 2024-2025  Lee Yingtong Li (RunasSudo)
 #
 #   This program is free software: you can redistribute it and/or modify
 #   it under the terms of the GNU Affero General Public License as published by
@@ -25,16 +25,6 @@ def aes_siv_encrypt(primary_master_key, hmac_master_key, plaintext, associated_d
 	Encrypt the given bytes using AES-SIV
 	"""
 	
-	if len(plaintext) == 0:
-		# https://github.com/pyca/cryptography/issues/10958 - cryptography AESSIV does not accept empty plaintext (e.g. root directory has empty directory ID)
-		
-		# Manually calculate the synthetic IV
-		siv = aes_siv_s2v(hmac_master_key, plaintext, associated_data)
-		
-		# Empty plaintext equals empty ciphertext, so result is just the SIV
-		return siv
-	
-	# In all other cases, use cryptography AESSIV
 	siv_and_ciphertext = AESSIV(hmac_master_key + primary_master_key).encrypt(plaintext, associated_data)
 	return siv_and_ciphertext
 
@@ -44,54 +34,3 @@ def aes_siv_decrypt(primary_master_key, hmac_master_key, siv_and_ciphertext, ass
 	"""
 	
 	return AESSIV(hmac_master_key + primary_master_key).decrypt(siv_and_ciphertext, associated_data)
-
-def aes_cmac(hmac_master_key, data):
-	mac = CMAC(AES(hmac_master_key))
-	mac.update(data)
-	return mac.finalize()
-
-def aes_siv_dbl(data):
-	# Based on miscreant.py by Phil Rogaway, MIT License
-	
-	overflow = 0
-	words = struct.unpack(b'!LLLL', data)
-	output_words = []
-	
-	for word in reversed(words):
-		new_word = (word << 1) & 0xFFFFFFFF
-		new_word |= overflow
-		overflow = int((word & 0x80000000) >= 0x80000000)
-		output_words.append(new_word)
-	
-	result = bytearray(struct.pack(b'!LLLL', *reversed(output_words)))
-	if overflow:
-		result[-1] ^= 0x87  # Foot-gun! Not constant time
-	
-	return result
-
-def aes_siv_s2v(hmac_master_key, plaintext, associated_data):
-	# Based on miscreant.py by Phil Rogaway, MIT License
-	
-	# Note: The standalone S2V returns CMAC(1) if the number of passed vectors is zero, however in SIV construction this case is never triggered, since we always pass plaintext as the last vector, so we omit this case.
-	
-	d = bytes(128//8)  # 128-bit blocks
-	d = aes_cmac(hmac_master_key, d)
-	
-	if associated_data:
-		for ad in associated_data:
-			d = aes_siv_dbl(d)
-			d = bytes(x ^ y for x, y in zip(d, aes_cmac(hmac_master_key, ad)))  # d ^= aes_cmac(hmac_master_key, ad)
-	
-	if len(plaintext) >= 128//8:  # 128 bits
-		mac = CMAC(AES(hmac_master_key))
-		difference = len(plaintext) - 128/8
-		mac.update(plaintext[:difference])
-		d = bytes(x ^ y for x, y in zip(d, plaintext[difference:]))  # d ^= plaintext[difference:]
-		mac.update(d)
-		return mac.finalize()
-	
-	d = aes_siv_dbl(d)
-	for i in range(len(plaintext)):
-		d[i] ^= plaintext[i]
-	d[len(plaintext)] ^= 0x80
-	return aes_cmac(hmac_master_key, d)