from copy import deepcopy
from Crypto.Cipher import AES
from base64 import b64decode, b64encode
+from osm_common.common_utils import FakeLock
+from threading import Lock
__author__ = "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>"
class DbBase(object):
- def __init__(self, logger_name='db'):
+ def __init__(self, logger_name='db', lock=False):
"""
- Constructor od dbBase
+ Constructor of dbBase
:param logger_name: logging name
+ :param lock: Used to protect simultaneous access to the same instance class by several threads:
+ False, None: Do not protect, this object will only be accessed by one thread
+ True: This object needs to be protected by several threads accessing.
+ Lock object. Use thi Lock for the threads access protection
"""
self.logger = logging.getLogger(logger_name)
- self.master_password = None
- self.secret_key = None
+ self.secret_key = None # 32 bytes length array used for encrypt/decrypt
+ if not lock:
+ self.lock = FakeLock()
+ elif lock is True:
+ self.lock = Lock()
+ elif isinstance(lock, Lock):
+ self.lock = lock
+ else:
+ raise ValueError("lock parameter must be a Lock classclass or boolean")
def db_connect(self, config, target_version=None):
"""
name: database name (mandatory)
user: database username
password: database password
- masterpassword: database password used for sensible information encryption
+ commonkey: common OSM key used for sensible information encryption
+ materpassword: same as commonkey, for backward compatibility. Deprecated, to be removed in the future
:param target_version: if provided it checks if database contains required version, raising exception otherwise.
:return: None or raises DbException on error
"""
"""
raise DbException("Method 'create' not implemented")
- def set_one(self, table, q_filter, update_dict, fail_on_empty=True):
+ def set_one(self, table, q_filter, update_dict, fail_on_empty=True, unset=None, pull=None, push=None):
"""
Modifies an entry at database
:param table: collection or table
:param update_dict: Plain dictionary with the content to be updated. It is a dot separated keys and a value
:param fail_on_empty: If nothing matches filter it returns None unless this flag is set tu True, in which case
it raises a DbException
+ :param unset: Plain dictionary with the content to be removed if exist. It is a dot separated keys, value is
+ ignored. If not exist, it is ignored
+ :param pull: Plain dictionary with the content to be removed from an array. It is a dot separated keys and value
+ if exist in the array is removed. If not exist, it is ignored
+ :param push: Plain dictionary with the content to be appended to an array. It is a dot separated keys and value
+ is appended to the end of the array
:return: Dict with the number of entries modified. None if no matching is found.
"""
raise DbException("Method 'set_one' not implemented")
"""
raise DbException("Method 'replace' not implemented")
- @staticmethod
- def _join_passwords(passwd_byte, passwd_str):
+ def _join_secret_key(self, update_key):
"""
- Modifies passwd_byte with the xor of passwd_str. Used for adding salt, join passwords, etc
- :param passwd_byte: original password in bytes, 32 byte length
- :param passwd_str: string salt to be added
- :return: modified password in bytes
+ Returns a xor byte combination of the internal secret_key and the provided update_key.
+ It does not modify the internal secret_key. Used for adding salt, join keys, etc.
+ :param update_key: Can be a string, byte or None. Recommended a long one (e.g. 32 byte length)
+ :return: joined key in bytes with a 32 bytes length. Can be None if both internal secret_key and update_key
+ are None
"""
- if not passwd_str:
- return passwd_byte
- secret_key = bytearray(passwd_byte)
- for i, b in enumerate(passwd_str.encode()):
- secret_key[i % 32] ^= b
- return bytes(secret_key)
-
- def set_secret_key(self, secret_key):
+ if not update_key:
+ return self.secret_key
+ elif isinstance(update_key, str):
+ update_key_bytes = update_key.encode()
+ else:
+ update_key_bytes = update_key
+
+ new_secret_key = bytearray(self.secret_key) if self.secret_key else bytearray(32)
+ for i, b in enumerate(update_key_bytes):
+ new_secret_key[i % 32] ^= b
+ return bytes(new_secret_key)
+
+ def set_secret_key(self, new_secret_key, replace=False):
"""
- Set internal secret key used for encryption
- :param secret_key: byte array length 32 with the secret_key
+ Updates internal secret_key used for encryption, with a byte xor
+ :param new_secret_key: string or byte array. It is recommended a 32 byte length
+ :param replace: if True, old value of internal secret_key is ignored and replaced. If false, a byte xor is used
:return: None
"""
- assert (len(secret_key) == 32)
- self.secret_key = self._join_passwords(secret_key, self.master_password)
+ if replace:
+ self.secret_key = None
+ self.secret_key = self._join_secret_key(new_secret_key)
def encrypt(self, value, schema_version=None, salt=None):
"""
:param salt: optional salt to be used. Must be str
:return: Encrypted content of value
"""
- if not schema_version or schema_version == '1.0':
+ if not self.secret_key or not schema_version or schema_version == '1.0':
return value
else:
- if not self.secret_key:
- raise DbException("Cannot encrypt. Missing secret_key", http_code=HTTPStatus.INTERNAL_SERVER_ERROR)
- secret_key = self._join_passwords(self.secret_key, salt)
+ secret_key = self._join_secret_key(salt)
cipher = AES.new(secret_key)
padded_private_msg = value + ('\0' * ((16-len(value)) % 16))
encrypted_msg = cipher.encrypt(padded_private_msg)
:param salt: optional salt to be used
:return: Plain content of value
"""
- if not schema_version or schema_version == '1.0':
+ if not self.secret_key or not schema_version or schema_version == '1.0':
return value
else:
- if not self.secret_key:
- raise DbException("Cannot decrypt. Missing secret_key", http_code=HTTPStatus.INTERNAL_SERVER_ERROR)
- secret_key = self._join_passwords(self.secret_key, salt)
+ secret_key = self._join_secret_key(salt)
encrypted_msg = b64decode(value)
cipher = AES.new(secret_key)
decrypted_msg = cipher.decrypt(encrypted_msg)