1#!/usr/bin/env python
2# Copyright 2017 The Chromium Authors
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8#     https://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15
16"""Generates a variety of chains where the target certificate varies in its key
17type and key usages."""
18
19import sys
20sys.path += ['../..']
21
22import gencerts
23
24# Self-signed root certificate (used as trust anchor).
25root = gencerts.create_self_signed_root_certificate('Root')
26
27# Intermediate certificate.
28intermediate = gencerts.create_intermediate_certificate('Intermediate', root)
29
30# Use either an RSA key, or an EC key for the target certificate. Generate the
31# possible keys ahead of time so as not to duplicate the work.
32
33KEYS = {
34  'rsa': gencerts.get_or_generate_rsa_key(
35      2048, gencerts.create_key_path('Target-rsa')),
36  'ec': gencerts.get_or_generate_ec_key(
37      'secp384r1', gencerts.create_key_path('Target-ec'))
38};
39
40KEY_USAGES = [ 'decipherOnly',
41               'digitalSignature',
42               'keyAgreement',
43               'keyEncipherment' ]
44
45# The proper key usage depends on the key purpose (serverAuth in this case),
46# and the key type. Generate a variety of combinations.
47for key_type in sorted(KEYS.keys()):
48  for key_usage in KEY_USAGES:
49    # Target certificate.
50    target = gencerts.create_end_entity_certificate('Target', intermediate)
51    target.get_extensions().set_property('extendedKeyUsage', 'serverAuth')
52    target.get_extensions().set_property('keyUsage',
53                                         'critical,%s' % (key_usage))
54
55    # Set the key.
56    target.set_key(KEYS[key_type])
57
58    # Write the chain.
59    chain = [target, intermediate, root]
60    description = ('Certificate chain where the target certificate uses a %s '
61                   'key and has the single key usage %s') % (key_type.upper(),
62                                                             key_usage)
63    gencerts.write_chain(description, chain,
64                         '%s-%s.pem' % (key_type, key_usage))
65