Python binascii 模块，Error() 实例源码

def b64decode(s, altchars=None, validate=False):
    """Decode the Base64 encoded bytes-like object or ASCII string s.

    Optional altchars must be a bytes-like object or ASCII string of length 2
    which specifies the alternative alphabet used instead of the '+' and '/'
    characters.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded.

    If validate is False (the default), characters that are neither in the
    normal base-64 alphabet nor the alternative alphabet are discarded prior
    to the padding check.  If validate is True, these non-alphabet characters
    in the input result in a binascii.Error.
    """
    s = _bytes_from_decode_data(s)
    if altchars is not None:
        altchars = _bytes_from_decode_data(altchars)
        assert len(altchars) == 2, repr(altchars)
        s = s.translate(bytes.maketrans(altchars, b'+/'))
    if validate and not re.match(b'^[A-Za-z0-9+/]*={0,2}$', s):
        raise binascii.Error('Non-base64 digit found')
    return binascii.a2b_base64(s)

def urlsafe_b64decode(s):
    """Decode bytes using the URL- and filesystem-safe Base64 alphabet.

    Argument s is a bytes-like object or ASCII string to decode.  The result
    is returned as a bytes object.  A binascii.Error is raised if the input
    is incorrectly padded.  Characters that are not in the URL-safe base-64
    alphabet, and are not a plus '+' or slash '/', are discarded prior to the
    padding check.

    The alphabet uses '-' instead of '+' and '_' instead of '/'.
    """
    s = _bytes_from_decode_data(s)
    s = s.translate(_urlsafe_decode_translation)
    return b64decode(s)



# Base32 encoding/decoding must be done in Python

def b16decode(s, casefold=False):
    """Decode the Base16 encoded bytes-like object or ASCII string s.

    Optional casefold is a flag specifying whether a lowercase alphabet is
    acceptable as input.  For security purposes, the default is False.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded or if there are non-alphabet characters present
    in the input.
    """
    s = _bytes_from_decode_data(s)
    if casefold:
        s = s.upper()
    if re.search(b'[^0-9A-F]', s):
        raise binascii.Error('Non-base16 digit found')
    return binascii.unhexlify(s)

#
# Ascii85 encoding/decoding
#

def b64decode(s, altchars=None):
    """Decode a Base64 encoded string.

    s is the string to decode.  Optional altchars must be a string of at least
    length 2 (additional characters are ignored) which specifies the
    alternative alphabet used instead of the '+' and '/' characters.

    The decoded string is returned.  A TypeError is raised if s were
    incorrectly padded or if there are non-alphabet characters present in the
    string.
    """
    if altchars is not None:
        s = _translate(s, {altchars[0]: '+', altchars[1]: '/'})
    try:
        return binascii.a2b_base64(s)
    except binascii.Error, msg:
        # Transform this exception for consistency
        raise TypeError(msg)

def _handle_request_exception(self, e):
        if isinstance(e, Finish):
            # Not an error; just finish the request without logging.
            if not self._finished:
                self.finish(*e.args)
            return
        try:
            self.log_exception(*sys.exc_info())
        except Exception:
            # An error here should still get a best-effort send_error()
            # to avoid leaking the connection.
            app_log.error("Error in exception logger", exc_info=True)
        if self._finished:
            # Extra errors after the request has been finished should
            # be logged, but there is no reason to continue to try and
            # send a response.
            return
        if isinstance(e, HTTPError):
            if e.status_code not in httputil.responses and not e.reason:
                gen_log.error("Bad HTTP status code: %d", e.status_code)
                self.send_error(500, exc_info=sys.exc_info())
            else:
                self.send_error(e.status_code, exc_info=sys.exc_info())
        else:
            self.send_error(500, exc_info=sys.exc_info())

def _handle_request_exception(self, e):
        if isinstance(e, Finish):
            # Not an error; just finish the request without logging.
            if not self._finished:
                self.finish(*e.args)
            return
        try:
            self.log_exception(*sys.exc_info())
        except Exception:
            # An error here should still get a best-effort send_error()
            # to avoid leaking the connection.
            app_log.error("Error in exception logger", exc_info=True)
        if self._finished:
            # Extra errors after the request has been finished should
            # be logged, but there is no reason to continue to try and
            # send a response.
            return
        if isinstance(e, HTTPError):
            if e.status_code not in httputil.responses and not e.reason:
                gen_log.error("Bad HTTP status code: %d", e.status_code)
                self.send_error(500, exc_info=sys.exc_info())
            else:
                self.send_error(e.status_code, exc_info=sys.exc_info())
        else:
            self.send_error(500, exc_info=sys.exc_info())

def parse_netntlm_resp_msg(headers, resp_header, seq):
    '''
    Parse the client response to the challenge
    '''
    try:
        header_val3 = headers[resp_header]
    except KeyError:
        return
    header_val3 = header_val3.split(' ', 1)

    # The header value can either start with NTLM or Negotiate
    if header_val3[0] == 'NTLM' or header_val3[0] == 'Negotiate':
        try:
            msg3 = base64.decodestring(header_val3[1])
        except binascii.Error:
            return
        return parse_ntlm_resp(msg3, seq)

def _authorize(self):
        # Authorization, (mostly) per the RFC
        try:
            authh = self.getHeader("Authorization")
            if not authh:
                self.user = self.password = ''
                return
            bas, upw = authh.split()
            if bas.lower() != "basic":
                raise ValueError
            upw = base64.decodestring(upw)
            self.user, self.password = upw.split(':', 1)
        except (binascii.Error, ValueError):
            self.user = self.password = ""
        except:
            log.err()
            self.user = self.password = ""

def _authResponse(self, auth, challenge):
        self._failresponse = self.esmtpAUTHDeclined

        try:
            challenge = base64.decodestring(challenge)
        except binascii.Error, e:
            # Illegal challenge, give up, then quit
            self.sendLine('*')
            self._okresponse = self.esmtpAUTHMalformedChallenge
            self._failresponse = self.esmtpAUTHMalformedChallenge
        else:
            resp = auth.challengeResponse(self.secret, challenge)
            self._expected = [235]
            self._okresponse = self.smtpState_from
            self.sendLine(encode_base64(resp, eol=""))

        if auth.getName() == "LOGIN" and challenge == "Username:":
            self._expected = [334]
            self._authinfo = auth
            self._okresponse = self.esmtpState_challenge

def b64decode(s, altchars=None):
    """Decode a Base64 encoded string.

    s is the string to decode.  Optional altchars must be a string of at least
    length 2 (additional characters are ignored) which specifies the
    alternative alphabet used instead of the '+' and '/' characters.

    The decoded string is returned.  A TypeError is raised if s were
    incorrectly padded or if there are non-alphabet characters present in the
    string.
    """
    if altchars is not None:
        s = _translate(s, {altchars[0]: '+', altchars[1]: '/'})
    try:
        return binascii.a2b_base64(s)
    except binascii.Error, msg:
        # Transform this exception for consistency
        raise TypeError(msg)

def test_ctor_w_key_and_format(self):
        """constructor -- 'key' and 'format' parameters"""

        # handle base32 encoding (the default)
        self.assertEqual(TOTP(KEY1).key, KEY1_RAW)

            # .. w/ lower case
        self.assertEqual(TOTP(KEY1.lower()).key, KEY1_RAW)

            # .. w/ spaces (e.g. user-entered data)
        self.assertEqual(TOTP(' 4aog gdbb qsyh ntuz ').key, KEY1_RAW)

            # .. w/ invalid char
        self.assertRaises(Base32DecodeError, TOTP, 'ao!ggdbbqsyhntuz')

        # handle hex encoding
        self.assertEqual(TOTP('e01c630c2184b076ce99', 'hex').key, KEY1_RAW)

            # .. w/ invalid char
        self.assertRaises(Base16DecodeError, TOTP, 'X01c630c2184b076ce99', 'hex')

        # handle raw bytes
        self.assertEqual(TOTP(KEY1_RAW, "raw").key, KEY1_RAW)

def _get_basicauth_credentials(request):
    authorization = AUTHORIZATION(request.environ)
    try:
        authmeth, auth = authorization.split(' ', 1)
    except ValueError:  # not enough values to unpack
        return None
    if authmeth.lower() == 'basic':
        try:
            auth = base64.b64decode(auth.strip().encode('ascii'))
        except binascii.Error:  # can't decode
            return None
        try:
            login, password = auth.decode('utf8').split(':', 1)
        except ValueError:  # not enough values to unpack
            return None
        return {'login': login, 'password': password}

    return None

def decode_b64jose(data, size=None, minimum=False):
    """Decode JOSE Base-64 field.

    :param unicode data:
    :param int size: Required length (after decoding).
    :param bool minimum: If ``True``, then `size` will be treated as
        minimum required length, as opposed to exact equality.

    :rtype: bytes

    """
    error_cls = TypeError if six.PY2 else binascii.Error
    try:
        decoded = b64.b64decode(data.encode())
    except error_cls as error:
        raise errors.DeserializationError(error)

    if size is not None and ((not minimum and len(decoded) != size) or
                             (minimum and len(decoded) < size)):
        raise errors.DeserializationError(
            "Expected at least or exactly {0} bytes".format(size))

    return decoded

def decode_hex16(value, size=None, minimum=False):
    """Decode hexlified field.

    :param unicode value:
    :param int size: Required length (after decoding).
    :param bool minimum: If ``True``, then `size` will be treated as
        minimum required length, as opposed to exact equality.

    :rtype: bytes

    """
    value = value.encode()
    if size is not None and ((not minimum and len(value) != size * 2) or
                             (minimum and len(value) < size * 2)):
        raise errors.DeserializationError()
    error_cls = TypeError if six.PY2 else binascii.Error
    try:
        return binascii.unhexlify(value)
    except error_cls as error:
        raise errors.DeserializationError(error)

def b64decode(s, altchars=None, validate=False):
    """Decode the Base64 encoded bytes-like object or ASCII string s.

    Optional altchars must be a bytes-like object or ASCII string of length 2
    which specifies the alternative alphabet used instead of the '+' and '/'
    characters.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded.

    If validate is False (the default), characters that are neither in the
    normal base-64 alphabet nor the alternative alphabet are discarded prior
    to the padding check.  If validate is True, these non-alphabet characters
    in the input result in a binascii.Error.
    """
    s = _bytes_from_decode_data(s)
    if altchars is not None:
        altchars = _bytes_from_decode_data(altchars)
        assert len(altchars) == 2, repr(altchars)
        s = s.translate(bytes.maketrans(altchars, b'+/'))
    if validate and not re.match(b'^[A-Za-z0-9+/]*={0,2}$', s):
        raise binascii.Error('Non-base64 digit found')
    return binascii.a2b_base64(s)

def urlsafe_b64decode(s):
    """Decode bytes using the URL- and filesystem-safe Base64 alphabet.

    Argument s is a bytes-like object or ASCII string to decode.  The result
    is returned as a bytes object.  A binascii.Error is raised if the input
    is incorrectly padded.  Characters that are not in the URL-safe base-64
    alphabet, and are not a plus '+' or slash '/', are discarded prior to the
    padding check.

    The alphabet uses '-' instead of '+' and '_' instead of '/'.
    """
    s = _bytes_from_decode_data(s)
    s = s.translate(_urlsafe_decode_translation)
    return b64decode(s)



# Base32 encoding/decoding must be done in Python

def b16decode(s, casefold=False):
    """Decode the Base16 encoded bytes-like object or ASCII string s.

    Optional casefold is a flag specifying whether a lowercase alphabet is
    acceptable as input.  For security purposes, the default is False.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded or if there are non-alphabet characters present
    in the input.
    """
    s = _bytes_from_decode_data(s)
    if casefold:
        s = s.upper()
    if re.search(b'[^0-9A-F]', s):
        raise binascii.Error('Non-base16 digit found')
    return binascii.unhexlify(s)

#
# Ascii85 encoding/decoding
#

def deserialize_compact(jwt):
    """ Deserialization of a compact representation of a :class:`~jwt.JWE`

    :param jwt: The serialized JWT to deserialize.
    :rtype: :class:`~jose.JWT`.
    :raises: :class:`~jose.Error` if the JWT is malformed
    """
    parts = jwt.split(six.b('.'))

    # http://tools.ietf.org/html/
    # draft-ietf-jose-json-web-encryption-23#section-9
    if len(parts) == 3:
        token_type = JWS
    elif len(parts) == 5:
        token_type = JWE
    else:
        raise Error('Malformed JWT')

    return token_type(*parts)

def parse_netntlm_resp_msg(headers, resp_header, seq):
    '''
    Parse the client response to the challenge
    '''
    try:
        header_val3 = headers[resp_header]
    except KeyError:
        return
    header_val3 = header_val3.split(' ', 1)

    # The header value can either start with NTLM or Negotiate
    if header_val3[0] == 'NTLM' or header_val3[0] == 'Negotiate':
        try:
            msg3 = base64.decodestring(header_val3[1])
        except binascii.Error:
            return
        return parse_ntlm_resp(msg3, seq)

def b64decode(s, altchars=None):
    """Decode a Base64 encoded string.

    s is the string to decode.  Optional altchars must be a string of at least
    length 2 (additional characters are ignored) which specifies the
    alternative alphabet used instead of the '+' and '/' characters.

    The decoded string is returned.  A TypeError is raised if s were
    incorrectly padded or if there are non-alphabet characters present in the
    string.
    """
    if altchars is not None:
        s = s.translate(string.maketrans(altchars[:2], '+/'))
    try:
        return binascii.a2b_base64(s)
    except binascii.Error, msg:
        # Transform this exception for consistency
        raise TypeError(msg)

def _get_user(self, environ):
        user = None
        http_auth = environ.get("HTTP_AUTHORIZATION")
        if http_auth and http_auth.startswith('Basic'):
            auth = http_auth.split(" ", 1)
            if len(auth) == 2:
                try:
                    # b64decode doesn't accept unicode in Python < 3.3
                    # so we need to convert it to a byte string
                    auth = base64.b64decode(auth[1].strip().encode('utf-8'))
                    if PY3:  # b64decode returns a byte string in Python 3
                        auth = auth.decode('utf-8')
                    auth = auth.split(":", 1)
                except TypeError as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                except binascii.Error as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                if len(auth) == 2:
                    user = auth[0]
        return user

def parse_as_public_pair(s):
    try:
        if s[:2] in (["02", "03", "04"]):
            return encoding.sec_to_public_pair(h2b(s))
    except (encoding.EncodingError, binascii.Error):
        pass
    for c in ",/":
        if c in s:
            s0, s1 = s.split(c, 1)
            v0 = parse_as_number(s0)
            if v0:
                if s1 in ("even", "odd"):
                    return ecdsa.public_pair_for_x(ecdsa.generator_secp256k1, v0, is_even=(s1=='even'))
                v1 = parse_as_number(s1)
                if v1:
                    if not ecdsa.is_public_pair_valid(ecdsa.generator_secp256k1, (v0, v1)):
                        sys.stderr.write("invalid (x, y) pair\n")
                        sys.exit(1)
                    return (v0, v1)

def netcode_and_type_for_text(text):
    # check for "public pair"
    try:
        LENGTH_LOOKUP = {
            33: "public_pair",
            65: "public_pair",
            16: "elc_seed",
            32: "elc_prv",
            64: "elc_pub",
        }
        as_bin = h2b(text)
        l = len(as_bin)
        if l in LENGTH_LOOKUP:
            return None, LENGTH_LOOKUP[l], as_bin
    except (binascii.Error, TypeError):
        pass

    data = encoding.a2b_hashed_base58(text)
    netcode, the_type = netcode_and_type_for_data(data)
    length = 1 if the_type in ["wif", "address"] else 4
    return netcode, the_type, data[length:]

def authenticate(self, request):
        """
        Returns a `User` if a correct username and password have been supplied
        using HTTP Basic authentication.  Otherwise returns `None`.
        """
        auth = get_authorization_header(request).split()

        if not auth or auth[0].lower() != b'basic':
            return None

        if len(auth) == 1:
            msg = _('Invalid basic header. No credentials provided.')
            raise exceptions.AuthenticationFailed(msg)
        elif len(auth) > 2:
            msg = _('Invalid basic header. Credentials string should not contain spaces.')
            raise exceptions.AuthenticationFailed(msg)

        try:
            auth_parts = base64.b64decode(auth[1]).decode(HTTP_HEADER_ENCODING).partition(':')
        except (TypeError, UnicodeDecodeError, binascii.Error):
            msg = _('Invalid basic header. Credentials not correctly base64 encoded.')
            raise exceptions.AuthenticationFailed(msg)

        userid, password = auth_parts[0], auth_parts[2]
        return self.authenticate_credentials(userid, password)

def b64decode(s, altchars=None):
    """Decode a Base64 encoded string.

    s is the string to decode.  Optional altchars must be a string of at least
    length 2 (additional characters are ignored) which specifies the
    alternative alphabet used instead of the '+' and '/' characters.

    The decoded string is returned.  A TypeError is raised if s were
    incorrectly padded or if there are non-alphabet characters present in the
    string.
    """
    if altchars is not None:
        s = s.translate(string.maketrans(altchars[:2], '+/'))
    try:
        return binascii.a2b_base64(s)
    except binascii.Error, msg:
        # Transform this exception for consistency
        raise TypeError(msg)

def LoadPlugins(plugins, plugindir, verbose):
    if plugins == '':
        return

    if plugindir == '':
        scriptPath = os.path.dirname(sys.argv[0])
    else:
        scriptPath = plugindir

    for plugin in sum(map(ProcessAt, plugins.split(',')), []):
        try:
            if not plugin.lower().endswith('.py'):
                plugin += '.py'
            if os.path.dirname(plugin) == '':
                if not os.path.exists(plugin):
                    scriptPlugin = os.path.join(scriptPath, plugin)
                    if os.path.exists(scriptPlugin):
                        plugin = scriptPlugin
            exec open(plugin, 'r') in globals(), globals()
        except Exception as e:
            print('Error loading plugin: %s' % plugin)
            if verbose:
                raise e

def deserialize_compact(jwt):
    """ Deserialization of a compact representation of a :class:`~jwt.JWE`

    :param jwt: The serialized JWT to deserialize.
    :rtype: :class:`~jose.JWT`.
    :raises: :class:`~jose.Error` if the JWT is malformed
    """
    parts = jwt.split(b'.')

    # http://tools.ietf.org/html/
    # draft-ietf-jose-json-web-encryption-23#section-9
    if len(parts) == 3:
        token_type = JWS
    elif len(parts) == 5:
        token_type = JWE
    else:
        raise Error('Malformed JWT')

    return token_type(*parts)

def normalize_transactiontest_fixture(fixture):
    normalized_fixture = {}

    if 'blocknumber' in fixture:
        normalized_fixture['blocknumber'] = to_int(fixture['blocknumber'])

    try:
        normalized_fixture['rlp'] = decode_hex(fixture['rlp'])
    except binascii.Error:
        normalized_fixture['rlpHex'] = fixture['rlp']

    if "sender" in fixture:
        # intentionally not normalized.
        normalized_fixture["transaction"] = fixture['transaction']
        # intentionally not normalized.
        normalized_fixture['sender'] = fixture['sender']

    return normalized_fixture

def _try_potential_passwords(self):
        valid_passwords = list()

        for potential_password in self._potential_passwords:
            try:
                potential_password = base64.b64decode(potential_password)
            except binascii.Error:
                continue
            else:
                try:
                    user, password = potential_password.split(':', maxsplit=1)
                    valid_passwords.append((user, password))
                except IndexError:
                    continue

        return valid_passwords

def test_uu(self):
        MAX_UU = 45
        lines = []
        for i in range(0, len(self.data), MAX_UU):
            b = self.type2test(self.rawdata[i:i+MAX_UU])
            a = binascii.b2a_uu(b)
            lines.append(a)
        res = bytes()
        for line in lines:
            a = self.type2test(line)
            b = binascii.a2b_uu(a)
            res += b
        self.assertEqual(res, self.rawdata)

        self.assertEqual(binascii.a2b_uu(b"\x7f"), b"\x00"*31)
        self.assertEqual(binascii.a2b_uu(b"\x80"), b"\x00"*32)
        self.assertEqual(binascii.a2b_uu(b"\xff"), b"\x00"*31)
        self.assertRaises(binascii.Error, binascii.a2b_uu, b"\xff\x00")
        self.assertRaises(binascii.Error, binascii.a2b_uu, b"!!!!")

        self.assertRaises(binascii.Error, binascii.b2a_uu, 46*b"!")

        # Issue #7701 (crash on a pydebug build)
        self.assertEqual(binascii.b2a_uu(b'x'), b'!>   \n')

def b64decode(s, altchars=None, validate=False):
    """Decode a Base64 encoded byte string.

    s is the byte string to decode.  Optional altchars must be a
    string of length 2 which specifies the alternative alphabet used
    instead of the '+' and '/' characters.

    The decoded string is returned.  A binascii.Error is raised if s is
    incorrectly padded.

    If validate is False (the default), non-base64-alphabet characters are
    discarded prior to the padding check.  If validate is True,
    non-base64-alphabet characters in the input result in a binascii.Error.
    """
    if not isinstance(s, bytes_types):
        raise TypeError("expected bytes, not %s" % s.__class__.__name__)
    if altchars is not None:
        if not isinstance(altchars, bytes_types):
            raise TypeError("expected bytes, not %s"
                            % altchars.__class__.__name__)
        assert len(altchars) == 2, repr(altchars)
        s = _translate(s, {chr(altchars[0]): b'+', chr(altchars[1]): b'/'})
    if validate and not re.match(b'^[A-Za-z0-9+/]*={0,2}$', s):
        raise binascii.Error('Non-base64 digit found')
    return binascii.a2b_base64(s)

def b16decode(s, casefold=False):
    """Decode a Base16 encoded byte string.

    s is the byte string to decode.  Optional casefold is a flag
    specifying whether a lowercase alphabet is acceptable as input.
    For security purposes, the default is False.

    The decoded byte string is returned.  binascii.Error is raised if
    s were incorrectly padded or if there are non-alphabet characters
    present in the string.
    """
    if not isinstance(s, bytes_types):
        raise TypeError("expected bytes, not %s" % s.__class__.__name__)
    if casefold:
        s = s.upper()
    if re.search(b'[^0-9A-F]', s):
        raise binascii.Error('Non-base16 digit found')
    return binascii.unhexlify(s)



# Legacy interface.  This code could be cleaned up since I don't believe
# binascii has any line length limitations.  It just doesn't seem worth it
# though.  The files should be opened in binary mode.

def b64decode(s, altchars=None, validate=False):
    """Decode the Base64 encoded bytes-like object or ASCII string s.

    Optional altchars must be a bytes-like object or ASCII string of length 2
    which specifies the alternative alphabet used instead of the '+' and '/'
    characters.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded.

    If validate is False (the default), characters that are neither in the
    normal base-64 alphabet nor the alternative alphabet are discarded prior
    to the padding check.  If validate is True, these non-alphabet characters
    in the input result in a binascii.Error.
    """
    s = _bytes_from_decode_data(s)
    if altchars is not None:
        altchars = _bytes_from_decode_data(altchars)
        assert len(altchars) == 2, repr(altchars)
        s = s.translate(bytes.maketrans(altchars, b'+/'))
    if validate and not re.match(b'^[A-Za-z0-9+/]*={0,2}$', s):
        raise binascii.Error('Non-base64 digit found')
    return binascii.a2b_base64(s)

def urlsafe_b64decode(s):
    """Decode bytes using the URL- and filesystem-safe Base64 alphabet.

    Argument s is a bytes-like object or ASCII string to decode.  The result
    is returned as a bytes object.  A binascii.Error is raised if the input
    is incorrectly padded.  Characters that are not in the URL-safe base-64
    alphabet, and are not a plus '+' or slash '/', are discarded prior to the
    padding check.

    The alphabet uses '-' instead of '+' and '_' instead of '/'.
    """
    s = _bytes_from_decode_data(s)
    s = s.translate(_urlsafe_decode_translation)
    return b64decode(s)



# Base32 encoding/decoding must be done in Python

def b16decode(s, casefold=False):
    """Decode the Base16 encoded bytes-like object or ASCII string s.

    Optional casefold is a flag specifying whether a lowercase alphabet is
    acceptable as input.  For security purposes, the default is False.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded or if there are non-alphabet characters present
    in the input.
    """
    s = _bytes_from_decode_data(s)
    if casefold:
        s = s.upper()
    if re.search(b'[^0-9A-F]', s):
        raise binascii.Error('Non-base16 digit found')
    return binascii.unhexlify(s)

#
# Ascii85 encoding/decoding
#

def _get_user(self, environ):
        user = None
        http_auth = environ.get("HTTP_AUTHORIZATION")
        if http_auth and http_auth.startswith('Basic'):
            auth = http_auth.split(" ", 1)
            if len(auth) == 2:
                try:
                    # b64decode doesn't accept unicode in Python < 3.3
                    # so we need to convert it to a byte string
                    auth = base64.b64decode(auth[1].strip().encode('utf-8'))
                    if PY3:  # b64decode returns a byte string in Python 3
                        auth = auth.decode('utf-8')
                    auth = auth.split(":", 1)
                except TypeError as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                except binascii.Error as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                if len(auth) == 2:
                    user = auth[0]
        return user

def _get_user(self, environ):
        user = None
        http_auth = environ.get("HTTP_AUTHORIZATION")
        if http_auth and http_auth.startswith('Basic'):
            auth = http_auth.split(" ", 1)
            if len(auth) == 2:
                try:
                    # b64decode doesn't accept unicode in Python < 3.3
                    # so we need to convert it to a byte string
                    auth = base64.b64decode(auth[1].strip().encode('utf-8'))
                    if PY3:  # b64decode returns a byte string in Python 3
                        auth = auth.decode('utf-8')
                    auth = auth.split(":", 1)
                except TypeError as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                except binascii.Error as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                if len(auth) == 2:
                    user = auth[0]
        return user

def decode_b64jose(data, size=None, minimum=False):
    """Decode JOSE Base-64 field.

    :param unicode data:
    :param int size: Required length (after decoding).
    :param bool minimum: If ``True``, then `size` will be treated as
        minimum required length, as opposed to exact equality.

    :rtype: bytes

    """
    error_cls = TypeError if six.PY2 else binascii.Error
    try:
        decoded = b64.b64decode(data.encode())
    except error_cls as error:
        raise errors.DeserializationError(error)

    if size is not None and ((not minimum and len(decoded) != size) or
                             (minimum and len(decoded) < size)):
        raise errors.DeserializationError(
            "Expected at least or exactly {0} bytes".format(size))

    return decoded

def decode_hex16(value, size=None, minimum=False):
    """Decode hexlified field.

    :param unicode value:
    :param int size: Required length (after decoding).
    :param bool minimum: If ``True``, then `size` will be treated as
        minimum required length, as opposed to exact equality.

    :rtype: bytes

    """
    value = value.encode()
    if size is not None and ((not minimum and len(value) != size * 2) or
                             (minimum and len(value) < size * 2)):
        raise errors.DeserializationError()
    error_cls = TypeError if six.PY2 else binascii.Error
    try:
        return binascii.unhexlify(value)
    except error_cls as error:
        raise errors.DeserializationError(error)

def b64decode(s, altchars=None, validate=False):
    """Decode the Base64 encoded bytes-like object or ASCII string s.

    Optional altchars must be a bytes-like object or ASCII string of length 2
    which specifies the alternative alphabet used instead of the '+' and '/'
    characters.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded.

    If validate is False (the default), characters that are neither in the
    normal base-64 alphabet nor the alternative alphabet are discarded prior
    to the padding check.  If validate is True, these non-alphabet characters
    in the input result in a binascii.Error.
    """
    s = _bytes_from_decode_data(s)
    if altchars is not None:
        altchars = _bytes_from_decode_data(altchars)
        assert len(altchars) == 2, repr(altchars)
        s = s.translate(bytes.maketrans(altchars, b'+/'))
    if validate and not re.match(b'^[A-Za-z0-9+/]*={0,2}$', s):
        raise binascii.Error('Non-base64 digit found')
    return binascii.a2b_base64(s)

def urlsafe_b64decode(s):
    """Decode bytes using the URL- and filesystem-safe Base64 alphabet.

    Argument s is a bytes-like object or ASCII string to decode.  The result
    is returned as a bytes object.  A binascii.Error is raised if the input
    is incorrectly padded.  Characters that are not in the URL-safe base-64
    alphabet, and are not a plus '+' or slash '/', are discarded prior to the
    padding check.

    The alphabet uses '-' instead of '+' and '_' instead of '/'.
    """
    s = _bytes_from_decode_data(s)
    s = s.translate(_urlsafe_decode_translation)
    return b64decode(s)



# Base32 encoding/decoding must be done in Python

def b16decode(s, casefold=False):
    """Decode the Base16 encoded bytes-like object or ASCII string s.

    Optional casefold is a flag specifying whether a lowercase alphabet is
    acceptable as input.  For security purposes, the default is False.

    The result is returned as a bytes object.  A binascii.Error is raised if
    s is incorrectly padded or if there are non-alphabet characters present
    in the input.
    """
    s = _bytes_from_decode_data(s)
    if casefold:
        s = s.upper()
    if re.search(b'[^0-9A-F]', s):
        raise binascii.Error('Non-base16 digit found')
    return binascii.unhexlify(s)

#
# Ascii85 encoding/decoding
#

def parse_netntlm_resp_msg(headers, resp_header, seq):
    '''
    Parse the client response to the challenge
    '''
    try:
        header_val3 = headers[resp_header]
    except KeyError:
        return
    header_val3 = header_val3.split(' ', 1)

    # The header value can either start with NTLM or Negotiate
    if header_val3[0] == 'NTLM' or header_val3[0] == 'Negotiate':
        try:
            msg3 = base64.decodestring(header_val3[1])
        except binascii.Error:
            return
        return parse_ntlm_resp(msg3, seq)

def LoadPlugins(plugins, verbose):
    if plugins == '':
        return
    scriptPath = os.path.dirname(sys.argv[0])
    for plugin in sum(map(ProcessAt, plugins.split(',')), []):
        try:
            if not plugin.lower().endswith('.py'):
                plugin += '.py'
            if os.path.dirname(plugin) == '':
                if not os.path.exists(plugin):
                    scriptPlugin = os.path.join(scriptPath, plugin)
                    if os.path.exists(scriptPlugin):
                        plugin = scriptPlugin
            exec open(plugin, 'r') in globals(), globals()
        except Exception as e:
            print('Error loading plugin: %s' % plugin)
            if verbose:
                raise e

def _get_user(self, environ):
        user = None
        http_auth = environ.get("HTTP_AUTHORIZATION")
        if http_auth and http_auth.startswith('Basic'):
            auth = http_auth.split(" ", 1)
            if len(auth) == 2:
                try:
                    # b64decode doesn't accept unicode in Python < 3.3
                    # so we need to convert it to a byte string
                    auth = base64.b64decode(auth[1].strip().encode('utf-8'))
                    if PY3:  # b64decode returns a byte string in Python 3
                        auth = auth.decode('utf-8')
                    auth = auth.split(":", 1)
                except TypeError as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                except binascii.Error as exc:
                    self.debug("Couldn't get username: %s", exc)
                    return user
                if len(auth) == 2:
                    user = auth[0]
        return user

def test_uu(self):
        MAX_UU = 45
        lines = []
        for i in range(0, len(self.data), MAX_UU):
            b = self.type2test(self.rawdata[i:i+MAX_UU])
            a = binascii.b2a_uu(b)
            lines.append(a)
        res = ""
        for line in lines:
            a = self.type2test(line)
            b = binascii.a2b_uu(a)
            res += b
        self.assertEqual(res, self.rawdata)

        self.assertEqual(binascii.a2b_uu("\x7f"), "\x00"*31)
        self.assertEqual(binascii.a2b_uu("\x80"), "\x00"*32)
        self.assertEqual(binascii.a2b_uu("\xff"), "\x00"*31)
        self.assertRaises(binascii.Error, binascii.a2b_uu, "\xff\x00")
        self.assertRaises(binascii.Error, binascii.a2b_uu, "!!!!")

        self.assertRaises(binascii.Error, binascii.b2a_uu, 46*"!")

        # Issue #7701 (crash on a pydebug build)
        self.assertEqual(binascii.b2a_uu('x'), '!>   \n')

def test_uu(self):
        MAX_UU = 45
        lines = []
        for i in range(0, len(self.data), MAX_UU):
            b = self.type2test(self.rawdata[i:i+MAX_UU])
            a = binascii.b2a_uu(b)
            lines.append(a)
        res = ""
        for line in lines:
            a = self.type2test(line)
            b = binascii.a2b_uu(a)
            res += b
        self.assertEqual(res, self.rawdata)

        self.assertEqual(binascii.a2b_uu("\x7f"), "\x00"*31)
        self.assertEqual(binascii.a2b_uu("\x80"), "\x00"*32)
        self.assertEqual(binascii.a2b_uu("\xff"), "\x00"*31)
        self.assertRaises(binascii.Error, binascii.a2b_uu, "\xff\x00")
        self.assertRaises(binascii.Error, binascii.a2b_uu, "!!!!")

        self.assertRaises(binascii.Error, binascii.b2a_uu, 46*"!")

        # Issue #7701 (crash on a pydebug build)
        self.assertEqual(binascii.b2a_uu('x'), '!>   \n')

def uu_decode(input, errors='strict'):
    assert errors == 'strict'
    infile = BytesIO(input)
    outfile = BytesIO()
    readline = infile.readline
    write = outfile.write

    # Find start of encoded data
    while 1:
        s = readline()
        if not s:
            raise ValueError('Missing "begin" line in input data')
        if s[:5] == b'begin':
            break

    # Decode
    while True:
        s = readline()
        if not s or s == b'end\n':
            break
        try:
            data = binascii.a2b_uu(s)
        except binascii.Error as v:
            # Workaround for broken uuencoders by /Fredrik Lundh
            nbytes = (((s[0]-32) & 63) * 4 + 5) // 3
            data = binascii.a2b_uu(s[:nbytes])
            #sys.stderr.write("Warning: %s\n" % str(v))
        write(data)
    if not s:
        raise ValueError('Truncated input data')

    return (outfile.getvalue(), len(input))

def standard_b64decode(s):
    """Decode bytes encoded with the standard Base64 alphabet.

    Argument s is a bytes-like object or ASCII string to decode.  The result
    is returned as a bytes object.  A binascii.Error is raised if the input
    is incorrectly padded.  Characters that are not in the standard alphabet
    are discarded prior to the padding check.
    """
    return b64decode(s)

def validate_token(key, token, user_id, action_id="", current_time=None):
    """Validates that the given token authorizes the user for the action.

    Tokens are invalid if the time of issue is too old or if the token
    does not match what generateToken outputs (i.e. the token was forged).

    Args:
        key: secret key to use.
        token: a string of the token generated by generateToken.
        user_id: the user ID of the authenticated user.
        action_id: a string identifier of the action they requested
                   authorization for.

    Returns:
        A boolean - True if the user is authorized for the action, False
        otherwise.
    """
    if not token:
        return False
    try:
        decoded = base64.urlsafe_b64decode(token)
        token_time = int(decoded.split(DELIMITER)[-1])
    except (TypeError, ValueError, binascii.Error):
        return False
    if current_time is None:
        current_time = time.time()
    # If the token is too old it's not valid.
    if current_time - token_time > DEFAULT_TIMEOUT_SECS:
        return False

    # The given token should match the generated one with the same time.
    expected_token = generate_token(key, user_id, action_id=action_id,
                                    when=token_time)
    if len(token) != len(expected_token):
        return False

    # Perform constant time comparison to avoid timing attacks
    different = 0
    for x, y in zip(bytearray(token), bytearray(expected_token)):
        different |= x ^ y
    return not different