dirmngr: Add framework to implement a fake CRL feature.

* dirmngr/fakecrl.c: New.
* dirmngr/dirmngr.h (opt): Add fake_crl.
* dirmngr/dirmngr.c (enum cmd_and_opt_values): Add oFakeCRL.
(opts): Add "fake-crl"
(parse_rereadable_options): Set opt.fake_crl.
* dirmngr/server.c (cmd_isvalid): Take care of fakce CRLs.

1 files changed, 63 insertions, 0 deletions

diff --git a/dirmngr/fakecrl.c b/dirmngr/fakecrl.c
new file mode 100644
index 000000000..43b68a57a
--- /dev/null
+++ b/dirmngr/fakecrl.c
@@ -0,0 +1,63 @@
+/* fakecrl.c - Debug code to test revocations.
+ * Copyright (C) 2023 g10 Code GmbH
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+/*
+ * For regression testing it is useful to have a way to claim that
+ * certain certificates are revoked.  We achieve this with the
+ * --fake-crl option which takes a file name as argument.  The format
+ * of the file is: empty lines and lines starting with a hash sign are
+ * ignored.  A line with the issuer DN in brackets starts entries for
+ * this issuer.  All following lines up to the next line with a
+ * bracket list revoked certificates.  For each revoked certificate
+ * the hexadecimal encoded serial number is listed, followed by the
+ * revocation date in ISO 14 byte notation, optionally followed by a
+ * reason keyword.  Example:
+ *---------------------
+ * # Sample Fake CRL
+ * [CN=Bayern-Softtoken-Issuing-CA-2019,OU=IT-DLZ,O=Freistaat Bayern,C=DE]
+ * 7FD62B1A9EA5BBC84971183080717004 20221125T074346
+ * 11223344556677                   20230101T000000  key_compromise
+ * 0000000000000042                 20221206T121200  certificate_hold
+ *
+ * [CN=CA IVBB Deutsche Telekom AG 18,OU=Bund,O=PKI-1-Verwaltung,C=DE]
+ * 735D1B97389F   20230210T083947
+ *---------------------
+ */
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "dirmngr.h"
+#include "crlcache.h"
+
+
+
+/* Returns 0 if the given certificate is not listed in the faked CRL
+ * or no fake CRL is configured.  It is expected that the caller then
+ * consults the real CRL.  */
+gpg_error_t
+fakecrl_isvalid (ctrl_t ctrl, const char *issuer_hash, const char *cert_id)
+{
+  (void)ctrl;
+  (void)issuer_hash;
+  (void)cert_id;
+  return 0;
+}