Merge remote-tracking branch 'remotes/dgilbert-gitlab/tags/pull-virtiofs-20210916...
[qemu.git] / authz / listfile.c
1 /*
2 * QEMU access control list file authorization driver
3 *
4 * Copyright (c) 2018 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "authz/listfile.h"
23 #include "trace.h"
24 #include "qemu/error-report.h"
25 #include "qemu/main-loop.h"
26 #include "qemu/module.h"
27 #include "qemu/sockets.h"
28 #include "qemu/filemonitor.h"
29 #include "qom/object_interfaces.h"
30 #include "qapi/qapi-visit-authz.h"
31 #include "qapi/qmp/qjson.h"
32 #include "qapi/qmp/qobject.h"
33 #include "qapi/qmp/qerror.h"
34 #include "qapi/qobject-input-visitor.h"
35
36
37 static bool
38 qauthz_list_file_is_allowed(QAuthZ *authz,
39 const char *identity,
40 Error **errp)
41 {
42 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(authz);
43 if (fauthz->list) {
44 return qauthz_is_allowed(fauthz->list, identity, errp);
45 }
46
47 return false;
48 }
49
50
51 static QAuthZ *
52 qauthz_list_file_load(QAuthZListFile *fauthz, Error **errp)
53 {
54 GError *err = NULL;
55 gchar *content = NULL;
56 gsize len;
57 QObject *obj = NULL;
58 QDict *pdict;
59 Visitor *v = NULL;
60 QAuthZ *ret = NULL;
61
62 trace_qauthz_list_file_load(fauthz, fauthz->filename);
63 if (!g_file_get_contents(fauthz->filename, &content, &len, &err)) {
64 error_setg(errp, "Unable to read '%s': %s",
65 fauthz->filename, err->message);
66 goto cleanup;
67 }
68
69 obj = qobject_from_json(content, errp);
70 if (!obj) {
71 goto cleanup;
72 }
73
74 pdict = qobject_to(QDict, obj);
75 if (!pdict) {
76 error_setg(errp, "File '%s' must contain a JSON object",
77 fauthz->filename);
78 goto cleanup;
79 }
80
81 v = qobject_input_visitor_new(obj);
82
83 ret = (QAuthZ *)user_creatable_add_type(TYPE_QAUTHZ_LIST,
84 NULL, pdict, v, errp);
85
86 cleanup:
87 visit_free(v);
88 qobject_unref(obj);
89 if (err) {
90 g_error_free(err);
91 }
92 g_free(content);
93 return ret;
94 }
95
96
97 static void
98 qauthz_list_file_event(int64_t wd G_GNUC_UNUSED,
99 QFileMonitorEvent ev G_GNUC_UNUSED,
100 const char *name G_GNUC_UNUSED,
101 void *opaque)
102 {
103 QAuthZListFile *fauthz = opaque;
104 Error *err = NULL;
105
106 if (ev != QFILE_MONITOR_EVENT_MODIFIED &&
107 ev != QFILE_MONITOR_EVENT_CREATED) {
108 return;
109 }
110
111 object_unref(OBJECT(fauthz->list));
112 fauthz->list = qauthz_list_file_load(fauthz, &err);
113 trace_qauthz_list_file_refresh(fauthz,
114 fauthz->filename, fauthz->list ? 1 : 0);
115 if (!fauthz->list) {
116 error_report_err(err);
117 }
118 }
119
120 static void
121 qauthz_list_file_complete(UserCreatable *uc, Error **errp)
122 {
123 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(uc);
124 gchar *dir = NULL, *file = NULL;
125
126 if (!fauthz->filename) {
127 error_setg(errp, "filename not provided");
128 return;
129 }
130
131 fauthz->list = qauthz_list_file_load(fauthz, errp);
132 if (!fauthz->list) {
133 return;
134 }
135
136 if (!fauthz->refresh) {
137 return;
138 }
139
140 fauthz->file_monitor = qemu_file_monitor_new(errp);
141 if (!fauthz->file_monitor) {
142 return;
143 }
144
145 dir = g_path_get_dirname(fauthz->filename);
146 if (g_str_equal(dir, ".")) {
147 error_setg(errp, "Filename must be an absolute path");
148 goto cleanup;
149 }
150 file = g_path_get_basename(fauthz->filename);
151 if (g_str_equal(file, ".")) {
152 error_setg(errp, "Path has no trailing filename component");
153 goto cleanup;
154 }
155
156 fauthz->file_watch = qemu_file_monitor_add_watch(
157 fauthz->file_monitor, dir, file,
158 qauthz_list_file_event, fauthz, errp);
159 if (fauthz->file_watch < 0) {
160 goto cleanup;
161 }
162
163 cleanup:
164 g_free(file);
165 g_free(dir);
166 }
167
168
169 static void
170 qauthz_list_file_prop_set_filename(Object *obj,
171 const char *value,
172 Error **errp G_GNUC_UNUSED)
173 {
174 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
175
176 g_free(fauthz->filename);
177 fauthz->filename = g_strdup(value);
178 }
179
180
181 static char *
182 qauthz_list_file_prop_get_filename(Object *obj,
183 Error **errp G_GNUC_UNUSED)
184 {
185 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
186
187 return g_strdup(fauthz->filename);
188 }
189
190
191 static void
192 qauthz_list_file_prop_set_refresh(Object *obj,
193 bool value,
194 Error **errp G_GNUC_UNUSED)
195 {
196 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
197
198 fauthz->refresh = value;
199 }
200
201
202 static bool
203 qauthz_list_file_prop_get_refresh(Object *obj,
204 Error **errp G_GNUC_UNUSED)
205 {
206 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
207
208 return fauthz->refresh;
209 }
210
211
212 static void
213 qauthz_list_file_finalize(Object *obj)
214 {
215 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj);
216
217 object_unref(OBJECT(fauthz->list));
218 g_free(fauthz->filename);
219 qemu_file_monitor_free(fauthz->file_monitor);
220 }
221
222
223 static void
224 qauthz_list_file_class_init(ObjectClass *oc, void *data)
225 {
226 UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
227 QAuthZClass *authz = QAUTHZ_CLASS(oc);
228
229 ucc->complete = qauthz_list_file_complete;
230
231 object_class_property_add_str(oc, "filename",
232 qauthz_list_file_prop_get_filename,
233 qauthz_list_file_prop_set_filename);
234 object_class_property_add_bool(oc, "refresh",
235 qauthz_list_file_prop_get_refresh,
236 qauthz_list_file_prop_set_refresh);
237
238 authz->is_allowed = qauthz_list_file_is_allowed;
239 }
240
241
242 static void
243 qauthz_list_file_init(Object *obj)
244 {
245 QAuthZListFile *authz = QAUTHZ_LIST_FILE(obj);
246
247 authz->file_watch = -1;
248 #ifdef CONFIG_INOTIFY1
249 authz->refresh = true;
250 #endif
251 }
252
253
254 QAuthZListFile *qauthz_list_file_new(const char *id,
255 const char *filename,
256 bool refresh,
257 Error **errp)
258 {
259 return QAUTHZ_LIST_FILE(
260 object_new_with_props(TYPE_QAUTHZ_LIST_FILE,
261 object_get_objects_root(),
262 id, errp,
263 "filename", filename,
264 "refresh", refresh ? "yes" : "no",
265 NULL));
266 }
267
268
269 static const TypeInfo qauthz_list_file_info = {
270 .parent = TYPE_QAUTHZ,
271 .name = TYPE_QAUTHZ_LIST_FILE,
272 .instance_init = qauthz_list_file_init,
273 .instance_size = sizeof(QAuthZListFile),
274 .instance_finalize = qauthz_list_file_finalize,
275 .class_init = qauthz_list_file_class_init,
276 .interfaces = (InterfaceInfo[]) {
277 { TYPE_USER_CREATABLE },
278 { }
279 }
280 };
281
282
283 static void
284 qauthz_list_file_register_types(void)
285 {
286 type_register_static(&qauthz_list_file_info);
287 }
288
289
290 type_init(qauthz_list_file_register_types);