python-telegram-bot/telegram/_passport/credentials.py
Bibo-Joshi 0a614e4bab
Documentation Improvements (#3370, #3376, #3366)
Co-authored-by: Viicos <65306057+Viicos@users.noreply.github.com>
2022-11-22 10:39:20 +01:00

462 lines
18 KiB
Python

#!/usr/bin/env python
#
# A library that provides a Python interface to the Telegram Bot API
# Copyright (C) 2015-2022
# Leandro Toledo de Souza <devs@python-telegram-bot.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser Public License for more details.
#
# You should have received a copy of the GNU Lesser Public License
# along with this program. If not, see [http://www.gnu.org/licenses/].
# pylint: disable=missing-module-docstring, redefined-builtin
import json
from base64 import b64decode
from typing import TYPE_CHECKING, List, Optional, no_type_check
try:
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.asymmetric.padding import MGF1, OAEP
from cryptography.hazmat.primitives.ciphers import Cipher
from cryptography.hazmat.primitives.ciphers.algorithms import AES
from cryptography.hazmat.primitives.ciphers.modes import CBC
from cryptography.hazmat.primitives.hashes import SHA1, SHA256, SHA512, Hash
CRYPTO_INSTALLED = True
except ImportError:
default_backend = None # type: ignore[assignment]
MGF1, OAEP, Cipher, AES, CBC = (None, None, None, None, None) # type: ignore[misc,assignment]
SHA1, SHA256, SHA512, Hash = (None, None, None, None) # type: ignore[misc,assignment]
CRYPTO_INSTALLED = False
from telegram._telegramobject import TelegramObject
from telegram._utils.types import JSONDict
from telegram.error import PassportDecryptionError
if TYPE_CHECKING:
from telegram import Bot
@no_type_check
def decrypt(secret, hash, data): # skipcq: PYL-W0622
"""
Decrypt per telegram docs at https://core.telegram.org/passport.
Args:
secret (:obj:`str` or :obj:`bytes`): The encryption secret, either as bytes or as a
base64 encoded string.
hash (:obj:`str` or :obj:`bytes`): The hash, either as bytes or as a
base64 encoded string.
data (:obj:`str` or :obj:`bytes`): The data to decrypt, either as bytes or as a
base64 encoded string.
file (:obj:`bool`): Force data to be treated as raw data, instead of trying to
b64decode it.
Raises:
:class:`PassportDecryptionError`: Given hash does not match hash of decrypted data.
Returns:
:obj:`bytes`: The decrypted data as bytes.
"""
if not CRYPTO_INSTALLED:
raise RuntimeError(
"To use Telegram Passports, PTB must be installed via `pip install "
"python-telegram-bot[passport]`."
)
# Make a SHA512 hash of secret + update
digest = Hash(SHA512(), backend=default_backend())
digest.update(secret + hash)
secret_hash_hash = digest.finalize()
# First 32 chars is our key, next 16 is the initialisation vector
key, init_vector = secret_hash_hash[:32], secret_hash_hash[32 : 32 + 16]
# Init a AES-CBC cipher and decrypt the data
cipher = Cipher(AES(key), CBC(init_vector), backend=default_backend())
decryptor = cipher.decryptor()
data = decryptor.update(data) + decryptor.finalize()
# Calculate SHA256 hash of the decrypted data
digest = Hash(SHA256(), backend=default_backend())
digest.update(data)
data_hash = digest.finalize()
# If the newly calculated hash did not match the one telegram gave us
if data_hash != hash:
# Raise a error that is caught inside telegram.PassportData and transformed into a warning
raise PassportDecryptionError(f"Hashes are not equal! {data_hash} != {hash}")
# Return data without padding
return data[data[0] :]
@no_type_check
def decrypt_json(secret, hash, data): # skipcq: PYL-W0622
"""Decrypts data using secret and hash and then decodes utf-8 string and loads json"""
return json.loads(decrypt(secret, hash, data).decode("utf-8"))
class EncryptedCredentials(TelegramObject):
"""Contains data required for decrypting and authenticating EncryptedPassportElement. See the
Telegram Passport Documentation for a complete description of the data decryption and
authentication processes.
Objects of this class are comparable in terms of equality. Two objects of this class are
considered equal, if their :attr:`data`, :attr:`hash` and :attr:`secret` are equal.
Note:
This object is decrypted only when originating from
:obj:`telegram.PassportData.decrypted_credentials`.
Args:
data (:class:`telegram.Credentials` or :obj:`str`): Decrypted data with unique user's
nonce, data hashes and secrets used for EncryptedPassportElement decryption and
authentication or base64 encrypted data.
hash (:obj:`str`): Base64-encoded data hash for data authentication.
secret (:obj:`str`): Decrypted or encrypted secret used for decryption.
Attributes:
data (:class:`telegram.Credentials` or :obj:`str`): Decrypted data with unique user's
nonce, data hashes and secrets used for EncryptedPassportElement decryption and
authentication or base64 encrypted data.
hash (:obj:`str`): Base64-encoded data hash for data authentication.
secret (:obj:`str`): Decrypted or encrypted secret used for decryption.
"""
__slots__ = (
"hash",
"secret",
"data",
"_decrypted_secret",
"_decrypted_data",
)
def __init__(
self,
data: str,
hash: str, # skipcq: PYL-W0622
secret: str,
*,
api_kwargs: JSONDict = None,
):
super().__init__(api_kwargs=api_kwargs)
# Required
self.data = data
self.hash = hash
self.secret = secret
self._id_attrs = (self.data, self.hash, self.secret)
self._decrypted_secret: Optional[str] = None
self._decrypted_data: Optional["Credentials"] = None
@property
def decrypted_secret(self) -> str:
"""
:obj:`str`: Lazily decrypt and return secret.
Raises:
telegram.error.PassportDecryptionError: Decryption failed. Usually due to bad
private/public key but can also suggest malformed/tampered data.
"""
if self._decrypted_secret is None:
if not CRYPTO_INSTALLED:
raise RuntimeError(
"To use Telegram Passports, PTB must be installed via `pip install "
"python-telegram-bot[passport]`."
)
# Try decrypting according to step 1 at
# https://core.telegram.org/passport#decrypting-data
# We make sure to base64 decode the secret first.
# Telegram says to use OAEP padding so we do that. The Mask Generation Function
# is the default for OAEP, the algorithm is the default for PHP which is what
# Telegram's backend servers run.
try:
self._decrypted_secret = self.get_bot().private_key.decrypt( # type: ignore
b64decode(self.secret),
OAEP(mgf=MGF1(algorithm=SHA1()), algorithm=SHA1(), label=None), # skipcq
)
except ValueError as exception:
# If decryption fails raise exception
raise PassportDecryptionError(exception) from exception
return self._decrypted_secret
@property
def decrypted_data(self) -> "Credentials":
"""
:class:`telegram.Credentials`: Lazily decrypt and return credentials data. This object
also contains the user specified nonce as
`decrypted_data.nonce`.
Raises:
telegram.error.PassportDecryptionError: Decryption failed. Usually due to bad
private/public key but can also suggest malformed/tampered data.
"""
if self._decrypted_data is None:
self._decrypted_data = Credentials.de_json(
decrypt_json(self.decrypted_secret, b64decode(self.hash), b64decode(self.data)),
self.get_bot(),
)
return self._decrypted_data # type: ignore[return-value]
class Credentials(TelegramObject):
"""
Attributes:
secure_data (:class:`telegram.SecureData`): Credentials for encrypted data
nonce (:obj:`str`): Bot-specified nonce
"""
__slots__ = ("nonce", "secure_data")
def __init__(
self,
secure_data: "SecureData",
nonce: str,
*,
api_kwargs: JSONDict = None,
):
super().__init__(api_kwargs=api_kwargs)
# Required
self.secure_data = secure_data
self.nonce = nonce
@classmethod
def de_json(cls, data: Optional[JSONDict], bot: "Bot") -> Optional["Credentials"]:
"""See :meth:`telegram.TelegramObject.de_json`."""
data = cls._parse_data(data)
if not data:
return None
data["secure_data"] = SecureData.de_json(data.get("secure_data"), bot=bot)
return super().de_json(data=data, bot=bot)
class SecureData(TelegramObject):
"""
This object represents the credentials that were used to decrypt the encrypted data.
All fields are optional and depend on fields that were requested.
Attributes:
personal_details (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
personal details.
passport (:class:`telegram.SecureValue`): Optional. Credentials for encrypted passport.
internal_passport (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
internal passport.
driver_license (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
driver license.
identity_card (:class:`telegram.SecureValue`): Optional. Credentials for encrypted ID card
address (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
residential address.
utility_bill (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
utility bill.
bank_statement (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
bank statement.
rental_agreement (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
rental agreement.
passport_registration (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
registration from internal passport.
temporary_registration (:class:`telegram.SecureValue`): Optional. Credentials for encrypted
temporary registration.
"""
__slots__ = (
"utility_bill",
"personal_details",
"temporary_registration",
"address",
"driver_license",
"rental_agreement",
"internal_passport",
"identity_card",
"bank_statement",
"passport",
"passport_registration",
)
def __init__(
self,
personal_details: "SecureValue" = None,
passport: "SecureValue" = None,
internal_passport: "SecureValue" = None,
driver_license: "SecureValue" = None,
identity_card: "SecureValue" = None,
address: "SecureValue" = None,
utility_bill: "SecureValue" = None,
bank_statement: "SecureValue" = None,
rental_agreement: "SecureValue" = None,
passport_registration: "SecureValue" = None,
temporary_registration: "SecureValue" = None,
*,
api_kwargs: JSONDict = None,
):
super().__init__(api_kwargs=api_kwargs)
# Optionals
self.temporary_registration = temporary_registration
self.passport_registration = passport_registration
self.rental_agreement = rental_agreement
self.bank_statement = bank_statement
self.utility_bill = utility_bill
self.address = address
self.identity_card = identity_card
self.driver_license = driver_license
self.internal_passport = internal_passport
self.passport = passport
self.personal_details = personal_details
@classmethod
def de_json(cls, data: Optional[JSONDict], bot: "Bot") -> Optional["SecureData"]:
"""See :meth:`telegram.TelegramObject.de_json`."""
data = cls._parse_data(data)
if not data:
return None
data["temporary_registration"] = SecureValue.de_json(
data.get("temporary_registration"), bot=bot
)
data["passport_registration"] = SecureValue.de_json(
data.get("passport_registration"), bot=bot
)
data["rental_agreement"] = SecureValue.de_json(data.get("rental_agreement"), bot=bot)
data["bank_statement"] = SecureValue.de_json(data.get("bank_statement"), bot=bot)
data["utility_bill"] = SecureValue.de_json(data.get("utility_bill"), bot=bot)
data["address"] = SecureValue.de_json(data.get("address"), bot=bot)
data["identity_card"] = SecureValue.de_json(data.get("identity_card"), bot=bot)
data["driver_license"] = SecureValue.de_json(data.get("driver_license"), bot=bot)
data["internal_passport"] = SecureValue.de_json(data.get("internal_passport"), bot=bot)
data["passport"] = SecureValue.de_json(data.get("passport"), bot=bot)
data["personal_details"] = SecureValue.de_json(data.get("personal_details"), bot=bot)
return super().de_json(data=data, bot=bot)
class SecureValue(TelegramObject):
"""
This object represents the credentials that were used to decrypt the encrypted value.
All fields are optional and depend on the type of field.
Attributes:
data (:class:`telegram.DataCredentials`): Optional. Credentials for encrypted Telegram
Passport data. Available for "personal_details", "passport", "driver_license",
"identity_card", "identity_passport" and "address" types.
front_side (:class:`telegram.FileCredentials`): Optional. Credentials for encrypted
document's front side. Available for "passport", "driver_license", "identity_card"
and "internal_passport".
reverse_side (:class:`telegram.FileCredentials`): Optional. Credentials for encrypted
document's reverse side. Available for "driver_license" and "identity_card".
selfie (:class:`telegram.FileCredentials`): Optional. Credentials for encrypted selfie
of the user with a document. Can be available for "passport", "driver_license",
"identity_card" and "internal_passport".
translation (List[:class:`telegram.FileCredentials`]): Optional. Credentials for an
encrypted translation of the document. Available for "passport", "driver_license",
"identity_card", "internal_passport", "utility_bill", "bank_statement",
"rental_agreement", "passport_registration" and "temporary_registration".
files (List[:class:`telegram.FileCredentials`]): Optional. Credentials for encrypted
files. Available for "utility_bill", "bank_statement", "rental_agreement",
"passport_registration" and "temporary_registration" types.
"""
__slots__ = ("data", "front_side", "reverse_side", "selfie", "files", "translation")
def __init__(
self,
data: "DataCredentials" = None,
front_side: "FileCredentials" = None,
reverse_side: "FileCredentials" = None,
selfie: "FileCredentials" = None,
files: List["FileCredentials"] = None,
translation: List["FileCredentials"] = None,
*,
api_kwargs: JSONDict = None,
):
super().__init__(api_kwargs=api_kwargs)
self.data = data
self.front_side = front_side
self.reverse_side = reverse_side
self.selfie = selfie
self.files = files
self.translation = translation
@classmethod
def de_json(cls, data: Optional[JSONDict], bot: "Bot") -> Optional["SecureValue"]:
"""See :meth:`telegram.TelegramObject.de_json`."""
data = cls._parse_data(data)
if not data:
return None
data["data"] = DataCredentials.de_json(data.get("data"), bot=bot)
data["front_side"] = FileCredentials.de_json(data.get("front_side"), bot=bot)
data["reverse_side"] = FileCredentials.de_json(data.get("reverse_side"), bot=bot)
data["selfie"] = FileCredentials.de_json(data.get("selfie"), bot=bot)
data["files"] = FileCredentials.de_list(data.get("files"), bot=bot)
data["translation"] = FileCredentials.de_list(data.get("translation"), bot=bot)
return super().de_json(data=data, bot=bot)
class _CredentialsBase(TelegramObject):
"""Base class for DataCredentials and FileCredentials."""
__slots__ = ("hash", "secret", "file_hash", "data_hash")
def __init__(
self, hash: str, secret: str, *, api_kwargs: JSONDict = None # skipcq: PYL-W0622
):
super().__init__(api_kwargs=api_kwargs)
self.hash = hash
self.secret = secret
# Aliases just to be sure
self.file_hash = self.hash
self.data_hash = self.hash
class DataCredentials(_CredentialsBase):
"""
These credentials can be used to decrypt encrypted data from the data field in
EncryptedPassportData.
Args:
data_hash (:obj:`str`): Checksum of encrypted data
secret (:obj:`str`): Secret of encrypted data
Attributes:
hash (:obj:`str`): Checksum of encrypted data
secret (:obj:`str`): Secret of encrypted data
"""
__slots__ = ()
def __init__(self, data_hash: str, secret: str, *, api_kwargs: JSONDict = None):
super().__init__(hash=data_hash, secret=secret, api_kwargs=api_kwargs)
class FileCredentials(_CredentialsBase):
"""
These credentials can be used to decrypt encrypted files from the front_side,
reverse_side, selfie and files fields in EncryptedPassportData.
Args:
file_hash (:obj:`str`): Checksum of encrypted file
secret (:obj:`str`): Secret of encrypted file
Attributes:
hash (:obj:`str`): Checksum of encrypted file
secret (:obj:`str`): Secret of encrypted file
"""
__slots__ = ()
def __init__(self, file_hash: str, secret: str, *, api_kwargs: JSONDict = None):
super().__init__(hash=file_hash, secret=secret, api_kwargs=api_kwargs)