import yaml
import logging
+import re
from http import HTTPStatus
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', master_password=None):
+ def __init__(self, logger_name='db', lock=False):
"""
- Constructor od dbBase
+ Constructor of dbBase
:param logger_name: logging name
- :param master_password: master password used for encrypt decrypt methods
+ :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 = master_password
- 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):
"""
Connect to database
- :param config: Configuration of database
+ :param config: Configuration of database. Contains among others:
+ host: database host (mandatory)
+ port: database port (mandatory)
+ name: database name (mandatory)
+ user: database username
+ password: database password
+ 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 'get_list' not implemented")
+ def count(self, table, q_filter=None):
+ """
+ Count the number of entries matching q_filter
+ :param table: collection or table
+ :param q_filter: Filter
+ :return: number of entries found (can be zero)
+ :raise: DbException on error
+ """
+ raise DbException("Method 'count' not implemented")
+
def get_one(self, table, q_filter=None, fail_on_empty=True, fail_on_more=True):
"""
Obtain one entry matching q_filter
"""
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")
- def set_list(self, table, q_filter, update_dict):
+ def set_list(self, table, q_filter, update_dict, unset=None, pull=None, push=None):
"""
Modifies al matching entries at database
:param table: collection or table
:param q_filter: Filter
:param update_dict: Plain dictionary with the content to be updated. It is a dot separated keys and a value
+ :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
"""
raise DbException("Method 'set_list' 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)
+ 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
- def set_secret_key(self, secret_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 get_secret_key(self):
+ """
+ Get the database secret key in case it is not done when "connect" is called. It can happens when database is
+ empty after an initial install. It should skip if secret is already obtained.
+ """
+ pass
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':
+ self.get_secret_key()
+ 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':
+ self.get_secret_key()
+ 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)
- unpadded_private_msg = decrypted_msg.decode().rstrip('\0')
+ try:
+ unpadded_private_msg = decrypted_msg.decode().rstrip('\0')
+ except UnicodeDecodeError:
+ raise DbException("Cannot decrypt information. Are you using same COMMONKEY in all OSM components?",
+ http_code=HTTPStatus.INTERNAL_SERVER_ERROR)
return unpadded_private_msg
+ def encrypt_decrypt_fields(self, item, action, fields=None, flags=re.I, schema_version=None, salt=None):
+ if not fields:
+ return
+ self.get_secret_key()
+ actions = ['encrypt', 'decrypt']
+ if action.lower() not in actions:
+ raise DbException("Unknown action ({}): Must be one of {}".format(action, actions),
+ http_code=HTTPStatus.INTERNAL_SERVER_ERROR)
+ method = self.encrypt if action.lower() == 'encrypt' else self.decrypt
+
+ def process(item):
+ if isinstance(item, list):
+ for elem in item:
+ process(elem)
+ elif isinstance(item, dict):
+ for key, val in item.items():
+ if any(re.search(f, key, flags) for f in fields) and isinstance(val, str):
+ item[key] = method(val, schema_version, salt)
+ else:
+ process(val)
+
+ process(item)
+
def deep_update_rfc7396(dict_to_change, dict_reference, key_list=None):
"""
Nothing happens if no match is found. If the value is None the matched elements are deleted.
$key: val In case a dictionary is passed in yaml format, if looks for all items in the array dict_to_change
that are dictionaries and contains this <key> equal to <val>. Several keys can be used by yaml
- format '{key: val, key: val, ...}'; and all of them mast match. Nothing happens if no match is
+ format '{key: val, key: val, ...}'; and all of them must match. Nothing happens if no match is
found. If value is None the matched items are deleted, otherwise they are edited.
$+val If no match if found (see '$val'), the value is appended to the array. If any match is found nothing
is changed. A value of None has not sense.