README.md
1Copyright (C) Internet Systems Consortium, Inc. ("ISC")
2
3SPDX-License-Identifier: MPL-2.0
4
5This Source Code Form is subject to the terms of the Mozilla Public
6License, v. 2.0. If a copy of the MPL was not distributed with this
7file, you can obtain one at https://mozilla.org/MPL/2.0/.
8
9See the COPYRIGHT file distributed with this work for additional
10information regarding copyright ownership.
11
12The `rsabigexponent` test is used to `check max-rsa-exponent-size`.
13
14We only run this test on builds without PKCS#11, as we have control over
15the RSA exponent size with plain OpenSSL. We have not explored how to do
16this with PKCS#11, which would require generating such a key and then
17signing a zone with it. Additionally, even with control of the exponent
18size with PKCS#11, generating a DNSKEY with this property and signing
19such a zone would be slow and undesirable for each test run; instead, we
20use a pregenerated DNSKEY and a saved signed zone. These are located in
21`rsabigexponent/ns2` and currently use RSASHA1 for the `DNSKEY`
22algorithm; however, that may need to be changed in the future.
23
24To generate the `DNSKEY` used in this test, we used `bigkey.c`, as
25dnssec-keygen is not capable of generating such keys.
26
27Do **not** remove `bigkey.c` as it may be needed to generate a new
28`DNSKEY` for testing purposes.
29
30`bigkey` is used to both test that we are not running under PKCS#11 and
31generate a `DNSKEY` key with a large RSA exponent.
32
33To regenerate `ns2/example.db.bad` comment out the range test in
34opensslrsa_parse before signing the zone with a ZSK key generated
35by `bigkey`.
36
37 if (BN_num_bits(e) > RSA_MAX_PUBEXP_BITS) {
38 DST_RET(ISC_R_RANGE);
39 }
40