Mercurial > libervia-backend
view sat/memory/crypto.py @ 3728:b15644cae50d
component AP gateway: JID/node ⟺ AP outbox conversion:
- convert a combination of JID and optional pubsub node to AP actor handle (see
`getJIDAndNode` for details) and vice versa
- the gateway now provides a Pubsub service
- retrieve pubsub node and convert it to AP collection, AP pagination is converted to RSM
- do the opposite: convert AP collection to pubsub and handle RSM request. Due to
ActivityStream collection pagination limitations, some RSM request produce inefficient
requests, but caching should be used most of the time in the future and avoid the
problem.
- set specific name to HTTP Server
- new `local_only` setting (`True` by default) to indicate if the gateway can request or
not XMPP Pubsub nodes from other servers
- disco info now specifies important features such as Pubsub RSM, and nodes metadata
ticket 363
author | Goffi <goffi@goffi.org> |
---|---|
date | Tue, 25 Jan 2022 17:54:06 +0100 |
parents | be6d91572633 |
children | 524856bd7b19 |
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#!/usr/bin/env python3 # SAT: a jabber client # Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org) # Copyright (C) 2013-2016 Adrien Cossa (souliane@mailoo.org) # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Affero General 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 Affero General Public License for more details. # You should have received a copy of the GNU Affero General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. from os import urandom from base64 import b64encode, b64decode from cryptography.hazmat.primitives import hashes from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes from cryptography.hazmat.backends import default_backend crypto_backend = default_backend() class BlockCipher: BLOCK_SIZE = 16 MAX_KEY_SIZE = 32 IV_SIZE = BLOCK_SIZE # initialization vector size, 16 bits @staticmethod def encrypt(key, text, leave_empty=True): """Encrypt a message. Based on http://stackoverflow.com/a/12525165 @param key (unicode): the encryption key @param text (unicode): the text to encrypt @param leave_empty (bool): if True, empty text will be returned "as is" @return (D(str)): base-64 encoded encrypted message """ if leave_empty and text == "": return "" iv = BlockCipher.getRandomKey() key = key.encode() key = ( key[: BlockCipher.MAX_KEY_SIZE] if len(key) >= BlockCipher.MAX_KEY_SIZE else BlockCipher.pad(key) ) cipher = Cipher(algorithms.AES(key), modes.CFB8(iv), backend=crypto_backend) encryptor = cipher.encryptor() encrypted = encryptor.update(BlockCipher.pad(text.encode())) + encryptor.finalize() return b64encode(iv + encrypted).decode() @staticmethod def decrypt(key, ciphertext, leave_empty=True): """Decrypt a message. Based on http://stackoverflow.com/a/12525165 @param key (unicode): the decryption key @param ciphertext (base-64 encoded str): the text to decrypt @param leave_empty (bool): if True, empty ciphertext will be returned "as is" @return: Deferred: str or None if the password could not be decrypted """ if leave_empty and ciphertext == "": return "" ciphertext = b64decode(ciphertext) iv, ciphertext = ( ciphertext[: BlockCipher.IV_SIZE], ciphertext[BlockCipher.IV_SIZE :], ) key = key.encode() key = ( key[: BlockCipher.MAX_KEY_SIZE] if len(key) >= BlockCipher.MAX_KEY_SIZE else BlockCipher.pad(key) ) cipher = Cipher(algorithms.AES(key), modes.CFB8(iv), backend=crypto_backend) decryptor = cipher.decryptor() decrypted = decryptor.update(ciphertext) + decryptor.finalize() return BlockCipher.unpad(decrypted) @staticmethod def getRandomKey(size=None, base64=False): """Return a random key suitable for block cipher encryption. Note: a good value for the key length is to make it as long as the block size. @param size: key length in bytes, positive or null (default: BlockCipher.IV_SIZE) @param base64: if True, encode the result to base-64 @return: str (eventually base-64 encoded) """ if size is None or size < 0: size = BlockCipher.IV_SIZE key = urandom(size) return b64encode(key) if base64 else key @staticmethod def pad(s): """Method from http://stackoverflow.com/a/12525165""" bs = BlockCipher.BLOCK_SIZE return s + (bs - len(s) % bs) * (chr(bs - len(s) % bs)).encode() @staticmethod def unpad(s): """Method from http://stackoverflow.com/a/12525165""" s = s.decode() return s[0 : -ord(s[-1])] class PasswordHasher: SALT_LEN = 16 # 128 bits @staticmethod def hash(password, salt=None, leave_empty=True): """Hash a password. @param password (str): the password to hash @param salt (base-64 encoded str): if not None, use the given salt instead of a random value @param leave_empty (bool): if True, empty password will be returned "as is" @return: Deferred: base-64 encoded str """ if leave_empty and password == "": return "" salt = ( b64decode(salt)[: PasswordHasher.SALT_LEN] if salt else urandom(PasswordHasher.SALT_LEN) ) # we use PyCrypto's PBKDF2 arguments while porting to crytography, to stay # compatible with existing installations. But this is temporary and we need # to update them to more secure values. kdf = PBKDF2HMAC( # FIXME: SHA1() is not secure, it is used here for historical reasons # and must be changed as soon as possible algorithm=hashes.SHA1(), length=16, salt=salt, iterations=1000, backend=crypto_backend ) key = kdf.derive(password.encode()) return b64encode(salt + key).decode() @staticmethod def verify(attempt, pwd_hash): """Verify a password attempt. @param attempt (str): the attempt to check @param pwd_hash (str): the hash of the password @return: Deferred: boolean """ assert isinstance(attempt, str) assert isinstance(pwd_hash, str) leave_empty = pwd_hash == "" attempt_hash = PasswordHasher.hash(attempt, pwd_hash, leave_empty) assert isinstance(attempt_hash, str) return attempt_hash == pwd_hash