qemu-e2k/authz/listfile.c

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authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
/*
* QEMU access control list file authorization driver
*
* Copyright (c) 2018 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 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 "authz/listfile.h"
#include "trace.h"
authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"
authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
#include "qemu/sockets.h"
#include "qemu/filemonitor.h"
#include "qom/object_interfaces.h"
#include "qapi/qapi-visit-authz.h"
#include "qapi/qmp/qjson.h"
#include "qapi/qmp/qobject.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qobject-input-visitor.h"
static bool
qauthz_list_file_is_allowed(QAuthZ *authz,
const char *identity,
Error **errp)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(authz);
if (fauthz->list) {
return qauthz_is_allowed(fauthz->list, identity, errp);
}
return false;
}
static QAuthZ *
qauthz_list_file_load(QAuthZListFile *fauthz, Error **errp)
{
GError *err = NULL;
gchar *content = NULL;
gsize len;
QObject *obj = NULL;
QDict *pdict;
Visitor *v = NULL;
QAuthZ *ret = NULL;
trace_qauthz_list_file_load(fauthz, fauthz->filename);
if (!g_file_get_contents(fauthz->filename, &content, &len, &err)) {
error_setg(errp, "Unable to read '%s': %s",
fauthz->filename, err->message);
goto cleanup;
}
obj = qobject_from_json(content, errp);
if (!obj) {
goto cleanup;
}
pdict = qobject_to(QDict, obj);
if (!pdict) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE, "obj", "dict");
goto cleanup;
}
v = qobject_input_visitor_new(obj);
ret = (QAuthZ *)user_creatable_add_type(TYPE_QAUTHZ_LIST,
NULL, pdict, v, errp);
cleanup:
visit_free(v);
qobject_unref(obj);
if (err) {
g_error_free(err);
}
g_free(content);
return ret;
}
static void
qauthz_list_file_event(int64_t wd G_GNUC_UNUSED,
authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
QFileMonitorEvent ev G_GNUC_UNUSED,
const char *name G_GNUC_UNUSED,
void *opaque)
{
QAuthZListFile *fauthz = opaque;
Error *err = NULL;
if (ev != QFILE_MONITOR_EVENT_MODIFIED &&
ev != QFILE_MONITOR_EVENT_CREATED) {
return;
}
object_unref(OBJECT(fauthz->list));
fauthz->list = qauthz_list_file_load(fauthz, &err);
trace_qauthz_list_file_refresh(fauthz,
fauthz->filename, fauthz->list ? 1 : 0);
if (!fauthz->list) {
error_report_err(err);
}
}
static void
qauthz_list_file_complete(UserCreatable *uc, Error **errp)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(uc);
gchar *dir = NULL, *file = NULL;
fauthz->list = qauthz_list_file_load(fauthz, errp);
if (!fauthz->refresh) {
return;
}
fauthz->file_monitor = qemu_file_monitor_new(errp);
if (!fauthz->file_monitor) {
return;
}
dir = g_path_get_dirname(fauthz->filename);
if (g_str_equal(dir, ".")) {
error_setg(errp, "Filename must be an absolute path");
goto cleanup;
}
file = g_path_get_basename(fauthz->filename);
if (g_str_equal(file, ".")) {
error_setg(errp, "Path has no trailing filename component");
goto cleanup;
}
fauthz->file_watch = qemu_file_monitor_add_watch(
fauthz->file_monitor, dir, file,
qauthz_list_file_event, fauthz, errp);
if (fauthz->file_watch < 0) {
goto cleanup;
}
cleanup:
g_free(file);
g_free(dir);
}
static void
qauthz_list_file_prop_set_filename(Object *obj,
const char *value,
Error **errp G_GNUC_UNUSED)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
g_free(fauthz->filename);
fauthz->filename = g_strdup(value);
}
static char *
qauthz_list_file_prop_get_filename(Object *obj,
Error **errp G_GNUC_UNUSED)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
return g_strdup(fauthz->filename);
}
static void
qauthz_list_file_prop_set_refresh(Object *obj,
bool value,
Error **errp G_GNUC_UNUSED)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
fauthz->refresh = value;
}
static bool
qauthz_list_file_prop_get_refresh(Object *obj,
Error **errp G_GNUC_UNUSED)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
return fauthz->refresh;
}
static void
qauthz_list_file_finalize(Object *obj)
{
QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
object_unref(OBJECT(fauthz->list));
g_free(fauthz->filename);
qemu_file_monitor_free(fauthz->file_monitor);
}
static void
qauthz_list_file_class_init(ObjectClass *oc, void *data)
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
QAuthZClass *authz = QAUTHZ_CLASS(oc);
ucc->complete = qauthz_list_file_complete;
object_class_property_add_str(oc, "filename",
qauthz_list_file_prop_get_filename,
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]
2020-05-05 17:29:22 +02:00
qauthz_list_file_prop_set_filename);
authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
object_class_property_add_bool(oc, "refresh",
qauthz_list_file_prop_get_refresh,
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]
2020-05-05 17:29:22 +02:00
qauthz_list_file_prop_set_refresh);
authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
authz->is_allowed = qauthz_list_file_is_allowed;
}
static void
qauthz_list_file_init(Object *obj)
{
QAuthZListFile *authz = QAUTHZ_LIST_FILE(obj);
authz->file_watch = -1;
#ifdef CONFIG_INOTIFY1
authz->refresh = true;
authz: add QAuthZListFile object type for a file access control list Add a QAuthZListFile object type that implements the QAuthZ interface. This built-in implementation is a proxy around the QAuthZList object type, initializing it from an external file, and optionally, automatically reloading it whenever it changes. To create an instance of this object via the QMP monitor, the syntax used would be: { "execute": "object-add", "arguments": { "qom-type": "authz-list-file", "id": "authz0", "props": { "filename": "/etc/qemu/vnc.acl", "refresh": true } } } If "refresh" is "yes", inotify is used to monitor the file, automatically reloading changes. If an error occurs during reloading, all authorizations will fail until the file is next successfully loaded. The /etc/qemu/vnc.acl file would contain a JSON representation of a QAuthZList object { "rules": [ { "match": "fred", "policy": "allow", "format": "exact" }, { "match": "bob", "policy": "allow", "format": "exact" }, { "match": "danb", "policy": "deny", "format": "glob" }, { "match": "dan*", "policy": "allow", "format": "exact" }, ], "policy": "deny" } This sets up an authorization rule that allows 'fred', 'bob' and anyone whose name starts with 'dan', except for 'danb'. Everyone unmatched is denied. The object can be loaded on the comand line using -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-11 13:19:59 +02:00
#endif
}
QAuthZListFile *qauthz_list_file_new(const char *id,
const char *filename,
bool refresh,
Error **errp)
{
return QAUTHZ_LIST_FILE(
object_new_with_props(TYPE_QAUTHZ_LIST_FILE,
object_get_objects_root(),
id, errp,
"filename", filename,
"refresh", refresh ? "yes" : "no",
NULL));
}
static const TypeInfo qauthz_list_file_info = {
.parent = TYPE_QAUTHZ,
.name = TYPE_QAUTHZ_LIST_FILE,
.instance_init = qauthz_list_file_init,
.instance_size = sizeof(QAuthZListFile),
.instance_finalize = qauthz_list_file_finalize,
.class_size = sizeof(QAuthZListFileClass),
.class_init = qauthz_list_file_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void
qauthz_list_file_register_types(void)
{
type_register_static(&qauthz_list_file_info);
}
type_init(qauthz_list_file_register_types);