qemu/crypto/tlscredsanon.c
Markus Armbruster d2623129a7 qom: Drop parameter @errp of object_property_add() & friends
The only way object_property_add() can fail is when a property with
the same name already exists.  Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.

Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent.  Parentage is
also under program control, so this is a programming error, too.

We have a bit over 500 callers.  Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.

The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.

Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.

When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.

Drop parameter @errp and assert the preconditions instead.

There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification".  Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
2020-05-15 07:07:58 +02:00

215 lines
5.6 KiB
C

/*
* QEMU crypto TLS anonymous credential support
*
* Copyright (c) 2015 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*/
#include "qemu/osdep.h"
#include "crypto/tlscredsanon.h"
#include "tlscredspriv.h"
#include "qapi/error.h"
#include "qemu/module.h"
#include "qom/object_interfaces.h"
#include "trace.h"
#ifdef CONFIG_GNUTLS
static int
qcrypto_tls_creds_anon_load(QCryptoTLSCredsAnon *creds,
Error **errp)
{
g_autofree char *dhparams = NULL;
int ret;
trace_qcrypto_tls_creds_anon_load(creds,
creds->parent_obj.dir ? creds->parent_obj.dir : "<nodir>");
if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
if (qcrypto_tls_creds_get_path(&creds->parent_obj,
QCRYPTO_TLS_CREDS_DH_PARAMS,
false, &dhparams, errp) < 0) {
return -1;
}
ret = gnutls_anon_allocate_server_credentials(&creds->data.server);
if (ret < 0) {
error_setg(errp, "Cannot allocate credentials: %s",
gnutls_strerror(ret));
return -1;
}
if (qcrypto_tls_creds_get_dh_params_file(&creds->parent_obj, dhparams,
&creds->parent_obj.dh_params,
errp) < 0) {
return -1;
}
gnutls_anon_set_server_dh_params(creds->data.server,
creds->parent_obj.dh_params);
} else {
ret = gnutls_anon_allocate_client_credentials(&creds->data.client);
if (ret < 0) {
error_setg(errp, "Cannot allocate credentials: %s",
gnutls_strerror(ret));
return -1;
}
}
return 0;
}
static void
qcrypto_tls_creds_anon_unload(QCryptoTLSCredsAnon *creds)
{
if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
if (creds->data.client) {
gnutls_anon_free_client_credentials(creds->data.client);
creds->data.client = NULL;
}
} else {
if (creds->data.server) {
gnutls_anon_free_server_credentials(creds->data.server);
creds->data.server = NULL;
}
}
if (creds->parent_obj.dh_params) {
gnutls_dh_params_deinit(creds->parent_obj.dh_params);
creds->parent_obj.dh_params = NULL;
}
}
#else /* ! CONFIG_GNUTLS */
static void
qcrypto_tls_creds_anon_load(QCryptoTLSCredsAnon *creds G_GNUC_UNUSED,
Error **errp)
{
error_setg(errp, "TLS credentials support requires GNUTLS");
}
static void
qcrypto_tls_creds_anon_unload(QCryptoTLSCredsAnon *creds G_GNUC_UNUSED)
{
/* nada */
}
#endif /* ! CONFIG_GNUTLS */
static void
qcrypto_tls_creds_anon_prop_set_loaded(Object *obj,
bool value,
Error **errp)
{
QCryptoTLSCredsAnon *creds = QCRYPTO_TLS_CREDS_ANON(obj);
if (value) {
qcrypto_tls_creds_anon_load(creds, errp);
} else {
qcrypto_tls_creds_anon_unload(creds);
}
}
#ifdef CONFIG_GNUTLS
static bool
qcrypto_tls_creds_anon_prop_get_loaded(Object *obj,
Error **errp G_GNUC_UNUSED)
{
QCryptoTLSCredsAnon *creds = QCRYPTO_TLS_CREDS_ANON(obj);
if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
return creds->data.server != NULL;
} else {
return creds->data.client != NULL;
}
}
#else /* ! CONFIG_GNUTLS */
static bool
qcrypto_tls_creds_anon_prop_get_loaded(Object *obj G_GNUC_UNUSED,
Error **errp G_GNUC_UNUSED)
{
return false;
}
#endif /* ! CONFIG_GNUTLS */
static void
qcrypto_tls_creds_anon_complete(UserCreatable *uc, Error **errp)
{
object_property_set_bool(OBJECT(uc), true, "loaded", errp);
}
static void
qcrypto_tls_creds_anon_finalize(Object *obj)
{
QCryptoTLSCredsAnon *creds = QCRYPTO_TLS_CREDS_ANON(obj);
qcrypto_tls_creds_anon_unload(creds);
}
static void
qcrypto_tls_creds_anon_class_init(ObjectClass *oc, void *data)
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
ucc->complete = qcrypto_tls_creds_anon_complete;
object_class_property_add_bool(oc, "loaded",
qcrypto_tls_creds_anon_prop_get_loaded,
qcrypto_tls_creds_anon_prop_set_loaded);
}
static const TypeInfo qcrypto_tls_creds_anon_info = {
.parent = TYPE_QCRYPTO_TLS_CREDS,
.name = TYPE_QCRYPTO_TLS_CREDS_ANON,
.instance_size = sizeof(QCryptoTLSCredsAnon),
.instance_finalize = qcrypto_tls_creds_anon_finalize,
.class_size = sizeof(QCryptoTLSCredsAnonClass),
.class_init = qcrypto_tls_creds_anon_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void
qcrypto_tls_creds_anon_register_types(void)
{
type_register_static(&qcrypto_tls_creds_anon_info);
}
type_init(qcrypto_tls_creds_anon_register_types);