diff options
Diffstat (limited to 'synapse/util/stringutils.py')
-rw-r--r-- | synapse/util/stringutils.py | 102 |
1 files changed, 35 insertions, 67 deletions
diff --git a/synapse/util/stringutils.py b/synapse/util/stringutils.py index 982c6d81ca..08c86e92b8 100644 --- a/synapse/util/stringutils.py +++ b/synapse/util/stringutils.py @@ -1,5 +1,6 @@ # -*- coding: utf-8 -*- # Copyright 2014-2016 OpenMarket Ltd +# Copyright 2020 The Matrix.org Foundation C.I.C. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. @@ -12,16 +13,21 @@ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. - +import itertools import random +import re import string +from collections import Iterable -import six -from six import PY2, PY3 -from six.moves import range +from synapse.api.errors import Codes, SynapseError _string_with_symbols = string.digits + string.ascii_letters + ".,;:^&*-_+=#~@" +# https://matrix.org/docs/spec/client_server/r0.6.0#post-matrix-client-r0-register-email-requesttoken +# Note: The : character is allowed here for older clients, but will be removed in a +# future release. Context: https://github.com/matrix-org/synapse/issues/6766 +client_secret_regex = re.compile(r"^[0-9a-zA-Z\.\=\_\-\:]+$") + # random_string and random_string_with_symbols are used for a range of things, # some cryptographically important, some less so. We use SystemRandom to make sure # we get cryptographically-secure randoms. @@ -37,75 +43,37 @@ def random_string_with_symbols(length): def is_ascii(s): - - if PY3: - if isinstance(s, bytes): - try: - s.decode("ascii").encode("ascii") - except UnicodeDecodeError: - return False - except UnicodeEncodeError: - return False - return True - - try: - s.encode("ascii") - except UnicodeEncodeError: - return False - except UnicodeDecodeError: - return False - else: + if isinstance(s, bytes): + try: + s.decode("ascii").encode("ascii") + except UnicodeDecodeError: + return False + except UnicodeEncodeError: + return False return True -def to_ascii(s): - """Converts a string to ascii if it is ascii, otherwise leave it alone. - - If given None then will return None. - """ - if PY3: - return s - - if s is None: - return None +def assert_valid_client_secret(client_secret): + """Validate that a given string matches the client_secret regex defined by the spec""" + if client_secret_regex.match(client_secret) is None: + raise SynapseError( + 400, "Invalid client_secret parameter", errcode=Codes.INVALID_PARAM + ) - try: - return s.encode("ascii") - except UnicodeEncodeError: - return s +def shortstr(iterable: Iterable, maxitems: int = 5) -> str: + """If iterable has maxitems or fewer, return the stringification of a list + containing those items. -def exception_to_unicode(e): - """Helper function to extract the text of an exception as a unicode string + Otherwise, return the stringification of a a list with the first maxitems items, + followed by "...". Args: - e (Exception): exception to be stringified - - Returns: - unicode + iterable: iterable to truncate + maxitems: number of items to return before truncating """ - # urgh, this is a mess. The basic problem here is that psycopg2 constructs its - # exceptions with PyErr_SetString, with a (possibly non-ascii) argument. str() will - # then produce the raw byte sequence. Under Python 2, this will then cause another - # error if it gets mixed with a `unicode` object, as per - # https://github.com/matrix-org/synapse/issues/4252 - - # First of all, if we're under python3, everything is fine because it will sort this - # nonsense out for us. - if not PY2: - return str(e) - - # otherwise let's have a stab at decoding the exception message. We'll circumvent - # Exception.__str__(), which would explode if someone raised Exception(u'non-ascii') - # and instead look at what is in the args member. - - if len(e.args) == 0: - return "" - elif len(e.args) > 1: - return six.text_type(repr(e.args)) - - msg = e.args[0] - if isinstance(msg, bytes): - return msg.decode("utf-8", errors="replace") - else: - return msg + + items = list(itertools.islice(iterable, maxitems + 1)) + if len(items) <= maxitems: + return str(items) + return "[" + ", ".join(repr(r) for r in items[:maxitems]) + ", ...]" |