def open_backup_file(file_path, private_key):
backup_file_text = file_path.read_text()
backup_file_json = json.loads(backup_file_text)
meta_data = backup_file_json["meta_data"]
meta_data_bytes = json.dumps(meta_data).encode()
sig = backup_file_json["signature"]
backup_pk = master_sk_to_backup_sk(private_key)
my_pubkey = backup_pk.get_g1()
key_base_64 = base64.b64encode(bytes(backup_pk))
f = Fernet(key_base_64)
encrypted_data = backup_file_json["data"].encode()
msg = std_hash(encrypted_data) + std_hash(meta_data_bytes)
signature = SignatureMPL.from_bytes(hexstr_to_bytes(sig))
pubkey = PublicKeyMPL.from_bytes(hexstr_to_bytes(meta_data["pubkey"]))
sig_match_my = AugSchemeMPL.verify(my_pubkey, msg, signature)
sig_match_backup = AugSchemeMPL.verify(pubkey, msg, signature)
assert sig_match_my is True
assert sig_match_backup is True
data_bytes = f.decrypt(encrypted_data)
data_text = data_bytes.decode()
data_json = json.loads(data_text)
unencrypted = {}
unencrypted["data"] = data_json
unencrypted["meta_data"] = meta_data
return unencrypted
def validate_alert(text: str, pubkey: str) -> bool:
json_obj = json.loads(text)
data = json_obj["data"]
message = bytes(data, "UTF-8")
signature = json_obj["signature"]
signature = SignatureMPL.from_bytes(hexstr_to_bytes(signature))
pubkey_bls = PublicKeyMPL.from_bytes(hexstr_to_bytes(pubkey))
sig_match_my = AugSchemeMPL.verify(pubkey_bls, message, signature)
return sig_match_my