def attack(decrypt_oracle, iv, c, t):
"""
Uses a chosen-ciphertext attack to decrypt the ciphertext.
:param decrypt_oracle: the decryption oracle
:param iv: the initialization vector
:param c: the ciphertext
:param t: the tag corresponding to the ciphertext
:return: the plaintext
"""
c_ = iv + c
p_ = decrypt_oracle(bytes(16), c_, c[-16:])
return p_[16:]
