async def decrypt_from_keystore(keystore: Keystore, password: str):
""" Get the phrase from the keystore
Args:
keystore (Keystore): keystore
password (str): password
Raises:
Exception: if password is incorrect
Exception: any inner exceptions
Returns:
[type]: the phrase from keystore
"""
if not isinstance(keystore, Keystore):
keystore = Keystore.from_dict(keystore)
kdfparams = keystore.crypto.kdfparams
try:
derived_key = await utils.pbkdf2(
password,
bytes.fromhex(kdfparams.salt),
kdfparams.c,
kdfparams.dklen,
HASHFUNCTION,
)
cipherbytes = bytes.fromhex(keystore.crypto.ciphertext)
blake256 = BLAKE2b.new(digest_bits=256)
blake256.update((derived_key[16:32] + cipherbytes))
mac = blake256.hexdigest()
if mac != keystore.crypto.mac:
raise Exception("Invalid Password")
ctr = Counter.new(NBITS,
initial_value=int(keystore.crypto.cipherparams.iv,
16))
aes_decipher = AES.new(derived_key[0:16], AES.MODE_CTR, counter=ctr)
decipher_bytes = aes_decipher.decrypt(cipherbytes)
res = bytes.decode(decipher_bytes)
return res
except Exception as err:
raise Exception(err)
async def encrypt_to_keystore(phrase: str, password: str):
"""Get the Keystore from the given phrase and password.
Args:
phrase (str): phrase
password (str): password
Raises:
Exception: if phrase is invalid
Returns:
[type]: Keystore
"""
if not validate_phrase(phrase):
raise Exception("Invalid BIP39 Phrase")
ID = str(uuid.uuid4())
salt = get_random_bytes(32)
iv = get_random_bytes(16)
kdfparams = KdfParams(prf=PRF , dklen=DKLEN , salt=salt.hex(),c=C)
ciptherparams = CipherParams(iv.hex())
derived_key = await utils.pbkdf2(
password, salt, kdfparams.c, kdfparams.dklen, HASHFUNCTION
)
ctr = Counter.new(NBITS, initial_value=int(iv.hex(), 16))
aes_cipher = AES.new(derived_key[0:16], AES.MODE_CTR, counter=ctr)
cipherbytes = aes_cipher.encrypt(phrase.encode("utf8"))
blake256 = BLAKE2b.new(digest_bits=256)
blake256.update((derived_key[16:32] + cipherbytes))
mac = blake256.hexdigest()
crypto_struct = CryptoStruct("aes-128-ctr" , cipherbytes.hex() , ciptherparams ,KDF,kdfparams,mac)
keystore = Keystore(crypto_struct , ID, 1 , META)
return keystore
