bbf6d9b026
Bugfix for feeds
- removed categories related and up
- load new books now working
- category random now working
login page is free of non accessible elements
boolean custom column is vivible in UI
books with only with certain languages can be shown
book shelfs can be deleted from UI
Anonymous user view is more resticted
Added browse of series in sidebar
Dependencys in vendor folder are updated to newer versions (licencs files are now present)
Bugfix editing Authors names
Made upload on windows working
872 lines
31 KiB
Python
872 lines
31 KiB
Python
# -*- coding: utf-8 -*-
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"""
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itsdangerous
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~~~~~~~~~~~~
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A module that implements various functions to deal with untrusted
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sources. Mainly useful for web applications.
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:copyright: (c) 2014 by Armin Ronacher and the Django Software Foundation.
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:license: BSD, see LICENSE for more details.
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"""
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import sys
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import hmac
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import zlib
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import time
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import base64
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import hashlib
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import operator
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from datetime import datetime
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PY2 = sys.version_info[0] == 2
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if PY2:
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from itertools import izip
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text_type = unicode
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int_to_byte = chr
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number_types = (int, long, float)
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else:
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from functools import reduce
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izip = zip
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text_type = str
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int_to_byte = operator.methodcaller('to_bytes', 1, 'big')
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number_types = (int, float)
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try:
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import simplejson as json
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except ImportError:
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import json
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class _CompactJSON(object):
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"""Wrapper around simplejson that strips whitespace.
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"""
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def loads(self, payload):
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return json.loads(payload)
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def dumps(self, obj):
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return json.dumps(obj, separators=(',', ':'))
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compact_json = _CompactJSON()
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# 2011/01/01 in UTC
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EPOCH = 1293840000
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def want_bytes(s, encoding='utf-8', errors='strict'):
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if isinstance(s, text_type):
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s = s.encode(encoding, errors)
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return s
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def is_text_serializer(serializer):
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"""Checks wheather a serializer generates text or binary."""
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return isinstance(serializer.dumps({}), text_type)
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# Starting with 3.3 the standard library has a c-implementation for
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# constant time string compares.
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_builtin_constant_time_compare = getattr(hmac, 'compare_digest', None)
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def constant_time_compare(val1, val2):
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"""Returns True if the two strings are equal, False otherwise.
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The time taken is independent of the number of characters that match. Do
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not use this function for anything else than comparision with known
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length targets.
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This is should be implemented in C in order to get it completely right.
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"""
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if _builtin_constant_time_compare is not None:
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return _builtin_constant_time_compare(val1, val2)
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len_eq = len(val1) == len(val2)
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if len_eq:
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result = 0
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left = val1
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else:
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result = 1
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left = val2
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for x, y in izip(bytearray(left), bytearray(val2)):
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result |= x ^ y
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return result == 0
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class BadData(Exception):
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"""Raised if bad data of any sort was encountered. This is the
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base for all exceptions that itsdangerous is currently using.
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.. versionadded:: 0.15
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"""
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message = None
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def __init__(self, message):
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Exception.__init__(self, message)
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self.message = message
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def __str__(self):
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return text_type(self.message)
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if PY2:
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__unicode__ = __str__
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def __str__(self):
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return self.__unicode__().encode('utf-8')
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class BadPayload(BadData):
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"""This error is raised in situations when payload is loaded without
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checking the signature first and an exception happend as a result of
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that. The original exception that caused that will be stored on the
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exception as :attr:`original_error`.
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This can also happen with a :class:`JSONWebSignatureSerializer` that
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is subclassed and uses a different serializer for the payload than
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the expected one.
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.. versionadded:: 0.15
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"""
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def __init__(self, message, original_error=None):
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BadData.__init__(self, message)
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#: If available, the error that indicates why the payload
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#: was not valid. This might be `None`.
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self.original_error = original_error
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class BadSignature(BadData):
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"""This error is raised if a signature does not match. As of
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itsdangerous 0.14 there are helpful attributes on the exception
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instances. You can also catch down the baseclass :exc:`BadData`.
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"""
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def __init__(self, message, payload=None):
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BadData.__init__(self, message)
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#: The payload that failed the signature test. In some
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#: situations you might still want to inspect this, even if
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#: you know it was tampered with.
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#:
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#: .. versionadded:: 0.14
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self.payload = payload
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class BadTimeSignature(BadSignature):
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"""Raised for time based signatures that fail. This is a subclass
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of :class:`BadSignature` so you can catch those down as well.
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"""
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def __init__(self, message, payload=None, date_signed=None):
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BadSignature.__init__(self, message, payload)
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#: If the signature expired this exposes the date of when the
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#: signature was created. This can be helpful in order to
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#: tell the user how long a link has been gone stale.
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#:
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#: .. versionadded:: 0.14
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self.date_signed = date_signed
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class BadHeader(BadSignature):
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"""Raised if a signed header is invalid in some form. This only
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happens for serializers that have a header that goes with the
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signature.
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.. versionadded:: 0.24
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"""
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def __init__(self, message, payload=None, header=None,
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original_error=None):
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BadSignature.__init__(self, message, payload)
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#: If the header is actually available but just malformed it
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#: might be stored here.
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self.header = header
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#: If available, the error that indicates why the payload
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#: was not valid. This might be `None`.
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self.original_error = original_error
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class SignatureExpired(BadTimeSignature):
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"""Signature timestamp is older than required max_age. This is a
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subclass of :exc:`BadTimeSignature` so you can use the baseclass for
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catching the error.
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"""
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def base64_encode(string):
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"""base64 encodes a single bytestring (and is tolerant to getting
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called with a unicode string).
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The resulting bytestring is safe for putting into URLs.
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"""
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string = want_bytes(string)
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return base64.urlsafe_b64encode(string).strip(b'=')
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def base64_decode(string):
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"""base64 decodes a single bytestring (and is tolerant to getting
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called with a unicode string).
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The result is also a bytestring.
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"""
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string = want_bytes(string, encoding='ascii', errors='ignore')
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return base64.urlsafe_b64decode(string + b'=' * (-len(string) % 4))
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def int_to_bytes(num):
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assert num >= 0
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rv = []
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while num:
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rv.append(int_to_byte(num & 0xff))
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num >>= 8
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return b''.join(reversed(rv))
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def bytes_to_int(bytestr):
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return reduce(lambda a, b: a << 8 | b, bytearray(bytestr), 0)
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class SigningAlgorithm(object):
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"""Subclasses of `SigningAlgorithm` have to implement `get_signature` to
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provide signature generation functionality.
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"""
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def get_signature(self, key, value):
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"""Returns the signature for the given key and value"""
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raise NotImplementedError()
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def verify_signature(self, key, value, sig):
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"""Verifies the given signature matches the expected signature"""
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return constant_time_compare(sig, self.get_signature(key, value))
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class NoneAlgorithm(SigningAlgorithm):
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"""This class provides a algorithm that does not perform any signing and
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returns an empty signature.
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"""
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def get_signature(self, key, value):
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return b''
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class HMACAlgorithm(SigningAlgorithm):
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"""This class provides signature generation using HMACs."""
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#: The digest method to use with the MAC algorithm. This defaults to sha1
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#: but can be changed for any other function in the hashlib module.
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default_digest_method = staticmethod(hashlib.sha1)
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def __init__(self, digest_method=None):
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if digest_method is None:
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digest_method = self.default_digest_method
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self.digest_method = digest_method
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def get_signature(self, key, value):
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mac = hmac.new(key, msg=value, digestmod=self.digest_method)
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return mac.digest()
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class Signer(object):
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"""This class can sign bytes and unsign it and validate the signature
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provided.
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Salt can be used to namespace the hash, so that a signed string is only
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valid for a given namespace. Leaving this at the default value or re-using
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a salt value across different parts of your application where the same
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signed value in one part can mean something different in another part
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is a security risk.
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See :ref:`the-salt` for an example of what the salt is doing and how you
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can utilize it.
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.. versionadded:: 0.14
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`key_derivation` and `digest_method` were added as arguments to the
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class constructor.
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.. versionadded:: 0.18
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`algorithm` was added as an argument to the class constructor.
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"""
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#: The digest method to use for the signer. This defaults to sha1 but can
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#: be changed for any other function in the hashlib module.
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#:
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#: .. versionchanged:: 0.14
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default_digest_method = staticmethod(hashlib.sha1)
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#: Controls how the key is derived. The default is Django style
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#: concatenation. Possible values are ``concat``, ``django-concat``
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#: and ``hmac``. This is used for deriving a key from the secret key
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#: with an added salt.
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#:
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#: .. versionadded:: 0.14
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default_key_derivation = 'django-concat'
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def __init__(self, secret_key, salt=None, sep='.', key_derivation=None,
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digest_method=None, algorithm=None):
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self.secret_key = want_bytes(secret_key)
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self.sep = sep
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self.salt = 'itsdangerous.Signer' if salt is None else salt
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if key_derivation is None:
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key_derivation = self.default_key_derivation
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self.key_derivation = key_derivation
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if digest_method is None:
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digest_method = self.default_digest_method
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self.digest_method = digest_method
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if algorithm is None:
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algorithm = HMACAlgorithm(self.digest_method)
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self.algorithm = algorithm
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def derive_key(self):
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"""This method is called to derive the key. If you're unhappy with
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the default key derivation choices you can override them here.
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Keep in mind that the key derivation in itsdangerous is not intended
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to be used as a security method to make a complex key out of a short
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password. Instead you should use large random secret keys.
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"""
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salt = want_bytes(self.salt)
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if self.key_derivation == 'concat':
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return self.digest_method(salt + self.secret_key).digest()
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elif self.key_derivation == 'django-concat':
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return self.digest_method(salt + b'signer' +
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self.secret_key).digest()
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elif self.key_derivation == 'hmac':
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mac = hmac.new(self.secret_key, digestmod=self.digest_method)
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mac.update(salt)
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return mac.digest()
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elif self.key_derivation == 'none':
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return self.secret_key
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else:
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raise TypeError('Unknown key derivation method')
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def get_signature(self, value):
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"""Returns the signature for the given value"""
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value = want_bytes(value)
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key = self.derive_key()
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sig = self.algorithm.get_signature(key, value)
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return base64_encode(sig)
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def sign(self, value):
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"""Signs the given string."""
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return value + want_bytes(self.sep) + self.get_signature(value)
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def verify_signature(self, value, sig):
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"""Verifies the signature for the given value."""
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key = self.derive_key()
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try:
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sig = base64_decode(sig)
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except Exception:
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return False
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return self.algorithm.verify_signature(key, value, sig)
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def unsign(self, signed_value):
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"""Unsigns the given string."""
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signed_value = want_bytes(signed_value)
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sep = want_bytes(self.sep)
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if sep not in signed_value:
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raise BadSignature('No %r found in value' % self.sep)
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value, sig = signed_value.rsplit(sep, 1)
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if self.verify_signature(value, sig):
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return value
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raise BadSignature('Signature %r does not match' % sig,
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payload=value)
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def validate(self, signed_value):
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"""Just validates the given signed value. Returns `True` if the
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signature exists and is valid, `False` otherwise."""
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try:
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self.unsign(signed_value)
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return True
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except BadSignature:
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return False
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class TimestampSigner(Signer):
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"""Works like the regular :class:`Signer` but also records the time
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of the signing and can be used to expire signatures. The unsign
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method can rause a :exc:`SignatureExpired` method if the unsigning
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failed because the signature is expired. This exception is a subclass
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of :exc:`BadSignature`.
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"""
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def get_timestamp(self):
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"""Returns the current timestamp. This implementation returns the
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seconds since 1/1/2011. The function must return an integer.
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"""
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return int(time.time() - EPOCH)
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def timestamp_to_datetime(self, ts):
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"""Used to convert the timestamp from `get_timestamp` into a
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datetime object.
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"""
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return datetime.utcfromtimestamp(ts + EPOCH)
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def sign(self, value):
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"""Signs the given string and also attaches a time information."""
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value = want_bytes(value)
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timestamp = base64_encode(int_to_bytes(self.get_timestamp()))
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sep = want_bytes(self.sep)
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value = value + sep + timestamp
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return value + sep + self.get_signature(value)
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def unsign(self, value, max_age=None, return_timestamp=False):
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"""Works like the regular :meth:`~Signer.unsign` but can also
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validate the time. See the base docstring of the class for
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the general behavior. If `return_timestamp` is set to `True`
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the timestamp of the signature will be returned as naive
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:class:`datetime.datetime` object in UTC.
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"""
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try:
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result = Signer.unsign(self, value)
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sig_error = None
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except BadSignature as e:
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sig_error = e
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result = e.payload or b''
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sep = want_bytes(self.sep)
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# If there is no timestamp in the result there is something
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# seriously wrong. In case there was a signature error, we raise
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# that one directly, otherwise we have a weird situation in which
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# we shouldn't have come except someone uses a time-based serializer
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# on non-timestamp data, so catch that.
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if not sep in result:
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if sig_error:
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raise sig_error
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raise BadTimeSignature('timestamp missing', payload=result)
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value, timestamp = result.rsplit(sep, 1)
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try:
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timestamp = bytes_to_int(base64_decode(timestamp))
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except Exception:
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timestamp = None
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# Signature is *not* okay. Raise a proper error now that we have
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# split the value and the timestamp.
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if sig_error is not None:
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raise BadTimeSignature(text_type(sig_error), payload=value,
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date_signed=timestamp)
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# Signature was okay but the timestamp is actually not there or
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# malformed. Should not happen, but well. We handle it nonetheless
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if timestamp is None:
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raise BadTimeSignature('Malformed timestamp', payload=value)
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# Check timestamp is not older than max_age
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if max_age is not None:
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age = self.get_timestamp() - timestamp
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if age > max_age:
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raise SignatureExpired(
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'Signature age %s > %s seconds' % (age, max_age),
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payload=value,
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date_signed=self.timestamp_to_datetime(timestamp))
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if return_timestamp:
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return value, self.timestamp_to_datetime(timestamp)
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return value
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def validate(self, signed_value, max_age=None):
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"""Just validates the given signed value. Returns `True` if the
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signature exists and is valid, `False` otherwise."""
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try:
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self.unsign(signed_value, max_age=max_age)
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return True
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except BadSignature:
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return False
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class Serializer(object):
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"""This class provides a serialization interface on top of the
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signer. It provides a similar API to json/pickle and other modules but is
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slightly differently structured internally. If you want to change the
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underlying implementation for parsing and loading you have to override the
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:meth:`load_payload` and :meth:`dump_payload` functions.
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This implementation uses simplejson if available for dumping and loading
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and will fall back to the standard library's json module if it's not
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available.
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Starting with 0.14 you do not need to subclass this class in order to
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switch out or customer the :class:`Signer`. You can instead also pass a
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different class to the constructor as well as keyword arguments as
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dictionary that should be forwarded::
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s = Serializer(signer_kwargs={'key_derivation': 'hmac'})
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.. versionchanged:: 0.14:
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The `signer` and `signer_kwargs` parameters were added to the
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constructor.
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"""
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#: If a serializer module or class is not passed to the constructor
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#: this one is picked up. This currently defaults to :mod:`json`.
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default_serializer = json
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#: The default :class:`Signer` class that is being used by this
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#: serializer.
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#:
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#: .. versionadded:: 0.14
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default_signer = Signer
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def __init__(self, secret_key, salt=b'itsdangerous', serializer=None,
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signer=None, signer_kwargs=None):
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self.secret_key = want_bytes(secret_key)
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self.salt = want_bytes(salt)
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if serializer is None:
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serializer = self.default_serializer
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self.serializer = serializer
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self.is_text_serializer = is_text_serializer(serializer)
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if signer is None:
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signer = self.default_signer
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self.signer = signer
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self.signer_kwargs = signer_kwargs or {}
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def load_payload(self, payload, serializer=None):
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"""Loads the encoded object. This function raises :class:`BadPayload`
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if the payload is not valid. The `serializer` parameter can be used to
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override the serializer stored on the class. The encoded payload is
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always byte based.
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"""
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if serializer is None:
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serializer = self.serializer
|
|
is_text = self.is_text_serializer
|
|
else:
|
|
is_text = is_text_serializer(serializer)
|
|
try:
|
|
if is_text:
|
|
payload = payload.decode('utf-8')
|
|
return serializer.loads(payload)
|
|
except Exception as e:
|
|
raise BadPayload('Could not load the payload because an '
|
|
'exception occurred on unserializing the data',
|
|
original_error=e)
|
|
|
|
def dump_payload(self, obj):
|
|
"""Dumps the encoded object. The return value is always a
|
|
bytestring. If the internal serializer is text based the value
|
|
will automatically be encoded to utf-8.
|
|
"""
|
|
return want_bytes(self.serializer.dumps(obj))
|
|
|
|
def make_signer(self, salt=None):
|
|
"""A method that creates a new instance of the signer to be used.
|
|
The default implementation uses the :class:`Signer` baseclass.
|
|
"""
|
|
if salt is None:
|
|
salt = self.salt
|
|
return self.signer(self.secret_key, salt=salt, **self.signer_kwargs)
|
|
|
|
def dumps(self, obj, salt=None):
|
|
"""Returns a signed string serialized with the internal serializer.
|
|
The return value can be either a byte or unicode string depending
|
|
on the format of the internal serializer.
|
|
"""
|
|
payload = want_bytes(self.dump_payload(obj))
|
|
rv = self.make_signer(salt).sign(payload)
|
|
if self.is_text_serializer:
|
|
rv = rv.decode('utf-8')
|
|
return rv
|
|
|
|
def dump(self, obj, f, salt=None):
|
|
"""Like :meth:`dumps` but dumps into a file. The file handle has
|
|
to be compatible with what the internal serializer expects.
|
|
"""
|
|
f.write(self.dumps(obj, salt))
|
|
|
|
def loads(self, s, salt=None):
|
|
"""Reverse of :meth:`dumps`, raises :exc:`BadSignature` if the
|
|
signature validation fails.
|
|
"""
|
|
s = want_bytes(s)
|
|
return self.load_payload(self.make_signer(salt).unsign(s))
|
|
|
|
def load(self, f, salt=None):
|
|
"""Like :meth:`loads` but loads from a file."""
|
|
return self.loads(f.read(), salt)
|
|
|
|
def loads_unsafe(self, s, salt=None):
|
|
"""Like :meth:`loads` but without verifying the signature. This is
|
|
potentially very dangerous to use depending on how your serializer
|
|
works. The return value is ``(signature_okay, payload)`` instead of
|
|
just the payload. The first item will be a boolean that indicates
|
|
if the signature is okay (``True``) or if it failed. This function
|
|
never fails.
|
|
|
|
Use it for debugging only and if you know that your serializer module
|
|
is not exploitable (eg: do not use it with a pickle serializer).
|
|
|
|
.. versionadded:: 0.15
|
|
"""
|
|
return self._loads_unsafe_impl(s, salt)
|
|
|
|
def _loads_unsafe_impl(self, s, salt, load_kwargs=None,
|
|
load_payload_kwargs=None):
|
|
"""Lowlevel helper function to implement :meth:`loads_unsafe` in
|
|
serializer subclasses.
|
|
"""
|
|
try:
|
|
return True, self.loads(s, salt=salt, **(load_kwargs or {}))
|
|
except BadSignature as e:
|
|
if e.payload is None:
|
|
return False, None
|
|
try:
|
|
return False, self.load_payload(e.payload,
|
|
**(load_payload_kwargs or {}))
|
|
except BadPayload:
|
|
return False, None
|
|
|
|
def load_unsafe(self, f, *args, **kwargs):
|
|
"""Like :meth:`loads_unsafe` but loads from a file.
|
|
|
|
.. versionadded:: 0.15
|
|
"""
|
|
return self.loads_unsafe(f.read(), *args, **kwargs)
|
|
|
|
|
|
class TimedSerializer(Serializer):
|
|
"""Uses the :class:`TimestampSigner` instead of the default
|
|
:meth:`Signer`.
|
|
"""
|
|
|
|
default_signer = TimestampSigner
|
|
|
|
def loads(self, s, max_age=None, return_timestamp=False, salt=None):
|
|
"""Reverse of :meth:`dumps`, raises :exc:`BadSignature` if the
|
|
signature validation fails. If a `max_age` is provided it will
|
|
ensure the signature is not older than that time in seconds. In
|
|
case the signature is outdated, :exc:`SignatureExpired` is raised
|
|
which is a subclass of :exc:`BadSignature`. All arguments are
|
|
forwarded to the signer's :meth:`~TimestampSigner.unsign` method.
|
|
"""
|
|
base64d, timestamp = self.make_signer(salt) \
|
|
.unsign(s, max_age, return_timestamp=True)
|
|
payload = self.load_payload(base64d)
|
|
if return_timestamp:
|
|
return payload, timestamp
|
|
return payload
|
|
|
|
def loads_unsafe(self, s, max_age=None, salt=None):
|
|
load_kwargs = {'max_age': max_age}
|
|
load_payload_kwargs = {}
|
|
return self._loads_unsafe_impl(s, salt, load_kwargs, load_payload_kwargs)
|
|
|
|
|
|
class JSONWebSignatureSerializer(Serializer):
|
|
"""This serializer implements JSON Web Signature (JWS) support. Only
|
|
supports the JWS Compact Serialization.
|
|
"""
|
|
|
|
jws_algorithms = {
|
|
'HS256': HMACAlgorithm(hashlib.sha256),
|
|
'HS384': HMACAlgorithm(hashlib.sha384),
|
|
'HS512': HMACAlgorithm(hashlib.sha512),
|
|
'none': NoneAlgorithm(),
|
|
}
|
|
|
|
#: The default algorithm to use for signature generation
|
|
default_algorithm = 'HS256'
|
|
|
|
default_serializer = compact_json
|
|
|
|
def __init__(self, secret_key, salt=None, serializer=None,
|
|
signer=None, signer_kwargs=None, algorithm_name=None):
|
|
Serializer.__init__(self, secret_key, salt, serializer,
|
|
signer, signer_kwargs)
|
|
if algorithm_name is None:
|
|
algorithm_name = self.default_algorithm
|
|
self.algorithm_name = algorithm_name
|
|
self.algorithm = self.make_algorithm(algorithm_name)
|
|
|
|
def load_payload(self, payload, return_header=False):
|
|
payload = want_bytes(payload)
|
|
if b'.' not in payload:
|
|
raise BadPayload('No "." found in value')
|
|
base64d_header, base64d_payload = payload.split(b'.', 1)
|
|
try:
|
|
json_header = base64_decode(base64d_header)
|
|
except Exception as e:
|
|
raise BadHeader('Could not base64 decode the header because of '
|
|
'an exception', original_error=e)
|
|
try:
|
|
json_payload = base64_decode(base64d_payload)
|
|
except Exception as e:
|
|
raise BadPayload('Could not base64 decode the payload because of '
|
|
'an exception', original_error=e)
|
|
try:
|
|
header = Serializer.load_payload(self, json_header,
|
|
serializer=json)
|
|
except BadData as e:
|
|
raise BadHeader('Could not unserialize header because it was '
|
|
'malformed', original_error=e)
|
|
if not isinstance(header, dict):
|
|
raise BadHeader('Header payload is not a JSON object',
|
|
header=header)
|
|
payload = Serializer.load_payload(self, json_payload)
|
|
if return_header:
|
|
return payload, header
|
|
return payload
|
|
|
|
def dump_payload(self, header, obj):
|
|
base64d_header = base64_encode(self.serializer.dumps(header))
|
|
base64d_payload = base64_encode(self.serializer.dumps(obj))
|
|
return base64d_header + b'.' + base64d_payload
|
|
|
|
def make_algorithm(self, algorithm_name):
|
|
try:
|
|
return self.jws_algorithms[algorithm_name]
|
|
except KeyError:
|
|
raise NotImplementedError('Algorithm not supported')
|
|
|
|
def make_signer(self, salt=None, algorithm=None):
|
|
if salt is None:
|
|
salt = self.salt
|
|
key_derivation = 'none' if salt is None else None
|
|
if algorithm is None:
|
|
algorithm = self.algorithm
|
|
return self.signer(self.secret_key, salt=salt, sep='.',
|
|
key_derivation=key_derivation, algorithm=algorithm)
|
|
|
|
def make_header(self, header_fields):
|
|
header = header_fields.copy() if header_fields else {}
|
|
header['alg'] = self.algorithm_name
|
|
return header
|
|
|
|
def dumps(self, obj, salt=None, header_fields=None):
|
|
"""Like :meth:`~Serializer.dumps` but creates a JSON Web Signature. It
|
|
also allows for specifying additional fields to be included in the JWS
|
|
Header.
|
|
"""
|
|
header = self.make_header(header_fields)
|
|
signer = self.make_signer(salt, self.algorithm)
|
|
return signer.sign(self.dump_payload(header, obj))
|
|
|
|
def loads(self, s, salt=None, return_header=False):
|
|
"""Reverse of :meth:`dumps`. If requested via `return_header` it will
|
|
return a tuple of payload and header.
|
|
"""
|
|
payload, header = self.load_payload(
|
|
self.make_signer(salt, self.algorithm).unsign(want_bytes(s)),
|
|
return_header=True)
|
|
if header.get('alg') != self.algorithm_name:
|
|
raise BadHeader('Algorithm mismatch', header=header,
|
|
payload=payload)
|
|
if return_header:
|
|
return payload, header
|
|
return payload
|
|
|
|
def loads_unsafe(self, s, salt=None, return_header=False):
|
|
kwargs = {'return_header': return_header}
|
|
return self._loads_unsafe_impl(s, salt, kwargs, kwargs)
|
|
|
|
|
|
class TimedJSONWebSignatureSerializer(JSONWebSignatureSerializer):
|
|
"""Works like the regular :class:`JSONWebSignatureSerializer` but also
|
|
records the time of the signing and can be used to expire signatures.
|
|
|
|
JWS currently does not specify this behavior but it mentions a possibility
|
|
extension like this in the spec. Expiry date is encoded into the header
|
|
similarily as specified in `draft-ietf-oauth-json-web-token
|
|
<http://self-issued.info/docs/draft-ietf-oauth-json-web-token.html#expDef`_.
|
|
|
|
The unsign method can raise a :exc:`SignatureExpired` method if the
|
|
unsigning failed because the signature is expired. This exception is a
|
|
subclass of :exc:`BadSignature`.
|
|
"""
|
|
|
|
DEFAULT_EXPIRES_IN = 3600
|
|
|
|
def __init__(self, secret_key, expires_in=None, **kwargs):
|
|
JSONWebSignatureSerializer.__init__(self, secret_key, **kwargs)
|
|
if expires_in is None:
|
|
expires_in = self.DEFAULT_EXPIRES_IN
|
|
self.expires_in = expires_in
|
|
|
|
def make_header(self, header_fields):
|
|
header = JSONWebSignatureSerializer.make_header(self, header_fields)
|
|
iat = self.now()
|
|
exp = iat + self.expires_in
|
|
header['iat'] = iat
|
|
header['exp'] = exp
|
|
return header
|
|
|
|
def loads(self, s, salt=None, return_header=False):
|
|
payload, header = JSONWebSignatureSerializer.loads(
|
|
self, s, salt, return_header=True)
|
|
|
|
if 'exp' not in header:
|
|
raise BadSignature('Missing expiry date', payload=payload)
|
|
|
|
if not (isinstance(header['exp'], number_types)
|
|
and header['exp'] > 0):
|
|
raise BadSignature('expiry date is not an IntDate',
|
|
payload=payload)
|
|
|
|
if header['exp'] < self.now():
|
|
raise SignatureExpired('Signature expired', payload=payload,
|
|
date_signed=self.get_issue_date(header))
|
|
|
|
if return_header:
|
|
return payload, header
|
|
return payload
|
|
|
|
def get_issue_date(self, header):
|
|
rv = header.get('iat')
|
|
if isinstance(rv, number_types):
|
|
return datetime.utcfromtimestamp(int(rv))
|
|
|
|
def now(self):
|
|
return int(time.time())
|
|
|
|
|
|
class URLSafeSerializerMixin(object):
|
|
"""Mixed in with a regular serializer it will attempt to zlib compress
|
|
the string to make it shorter if necessary. It will also base64 encode
|
|
the string so that it can safely be placed in a URL.
|
|
"""
|
|
|
|
def load_payload(self, payload):
|
|
decompress = False
|
|
if payload.startswith(b'.'):
|
|
payload = payload[1:]
|
|
decompress = True
|
|
try:
|
|
json = base64_decode(payload)
|
|
except Exception as e:
|
|
raise BadPayload('Could not base64 decode the payload because of '
|
|
'an exception', original_error=e)
|
|
if decompress:
|
|
try:
|
|
json = zlib.decompress(json)
|
|
except Exception as e:
|
|
raise BadPayload('Could not zlib decompress the payload before '
|
|
'decoding the payload', original_error=e)
|
|
return super(URLSafeSerializerMixin, self).load_payload(json)
|
|
|
|
def dump_payload(self, obj):
|
|
json = super(URLSafeSerializerMixin, self).dump_payload(obj)
|
|
is_compressed = False
|
|
compressed = zlib.compress(json)
|
|
if len(compressed) < (len(json) - 1):
|
|
json = compressed
|
|
is_compressed = True
|
|
base64d = base64_encode(json)
|
|
if is_compressed:
|
|
base64d = b'.' + base64d
|
|
return base64d
|
|
|
|
|
|
class URLSafeSerializer(URLSafeSerializerMixin, Serializer):
|
|
"""Works like :class:`Serializer` but dumps and loads into a URL
|
|
safe string consisting of the upper and lowercase character of the
|
|
alphabet as well as ``'_'``, ``'-'`` and ``'.'``.
|
|
"""
|
|
default_serializer = compact_json
|
|
|
|
|
|
class URLSafeTimedSerializer(URLSafeSerializerMixin, TimedSerializer):
|
|
"""Works like :class:`TimedSerializer` but dumps and loads into a URL
|
|
safe string consisting of the upper and lowercase character of the
|
|
alphabet as well as ``'_'``, ``'-'`` and ``'.'``.
|
|
"""
|
|
default_serializer = compact_json
|