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/qobject-input-visitor.h" 34 35 36 static bool 37 qauthz_list_file_is_allowed(QAuthZ *authz, 38 const char *identity, 39 Error **errp) 40 { 41 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(authz); 42 if (fauthz->list) { 43 return qauthz_is_allowed(fauthz->list, identity, errp); 44 } 45 46 return false; 47 } 48 49 50 static QAuthZ * 51 qauthz_list_file_load(QAuthZListFile *fauthz, Error **errp) 52 { 53 GError *err = NULL; 54 gchar *content = NULL; 55 gsize len; 56 QObject *obj = NULL; 57 QDict *pdict; 58 Visitor *v = NULL; 59 QAuthZ *ret = NULL; 60 61 trace_qauthz_list_file_load(fauthz, fauthz->filename); 62 if (!g_file_get_contents(fauthz->filename, &content, &len, &err)) { 63 error_setg(errp, "Unable to read '%s': %s", 64 fauthz->filename, err->message); 65 goto cleanup; 66 } 67 68 obj = qobject_from_json(content, errp); 69 if (!obj) { 70 goto cleanup; 71 } 72 73 pdict = qobject_to(QDict, obj); 74 if (!pdict) { 75 error_setg(errp, "File '%s' must contain a JSON object", 76 fauthz->filename); 77 goto cleanup; 78 } 79 80 v = qobject_input_visitor_new(obj); 81 82 ret = (QAuthZ *)user_creatable_add_type(TYPE_QAUTHZ_LIST, 83 NULL, pdict, v, errp); 84 85 cleanup: 86 visit_free(v); 87 qobject_unref(obj); 88 if (err) { 89 g_error_free(err); 90 } 91 g_free(content); 92 return ret; 93 } 94 95 96 static void 97 qauthz_list_file_event(int64_t wd G_GNUC_UNUSED, 98 QFileMonitorEvent ev G_GNUC_UNUSED, 99 const char *name G_GNUC_UNUSED, 100 void *opaque) 101 { 102 QAuthZListFile *fauthz = opaque; 103 Error *err = NULL; 104 105 if (ev != QFILE_MONITOR_EVENT_MODIFIED && 106 ev != QFILE_MONITOR_EVENT_CREATED) { 107 return; 108 } 109 110 object_unref(OBJECT(fauthz->list)); 111 fauthz->list = qauthz_list_file_load(fauthz, &err); 112 trace_qauthz_list_file_refresh(fauthz, 113 fauthz->filename, fauthz->list ? 1 : 0); 114 if (!fauthz->list) { 115 error_report_err(err); 116 } 117 } 118 119 static void 120 qauthz_list_file_complete(UserCreatable *uc, Error **errp) 121 { 122 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(uc); 123 gchar *dir = NULL, *file = NULL; 124 125 if (!fauthz->filename) { 126 error_setg(errp, "filename not provided"); 127 return; 128 } 129 130 fauthz->list = qauthz_list_file_load(fauthz, errp); 131 if (!fauthz->list) { 132 return; 133 } 134 135 if (!fauthz->refresh) { 136 return; 137 } 138 139 fauthz->file_monitor = qemu_file_monitor_new(errp); 140 if (!fauthz->file_monitor) { 141 return; 142 } 143 144 dir = g_path_get_dirname(fauthz->filename); 145 if (g_str_equal(dir, ".")) { 146 error_setg(errp, "Filename must be an absolute path"); 147 goto cleanup; 148 } 149 file = g_path_get_basename(fauthz->filename); 150 if (g_str_equal(file, ".")) { 151 error_setg(errp, "Path has no trailing filename component"); 152 goto cleanup; 153 } 154 155 fauthz->file_watch = qemu_file_monitor_add_watch( 156 fauthz->file_monitor, dir, file, 157 qauthz_list_file_event, fauthz, errp); 158 if (fauthz->file_watch < 0) { 159 goto cleanup; 160 } 161 162 cleanup: 163 g_free(file); 164 g_free(dir); 165 } 166 167 168 static void 169 qauthz_list_file_prop_set_filename(Object *obj, 170 const char *value, 171 Error **errp G_GNUC_UNUSED) 172 { 173 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj); 174 175 g_free(fauthz->filename); 176 fauthz->filename = g_strdup(value); 177 } 178 179 180 static char * 181 qauthz_list_file_prop_get_filename(Object *obj, 182 Error **errp G_GNUC_UNUSED) 183 { 184 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj); 185 186 return g_strdup(fauthz->filename); 187 } 188 189 190 static void 191 qauthz_list_file_prop_set_refresh(Object *obj, 192 bool value, 193 Error **errp G_GNUC_UNUSED) 194 { 195 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj); 196 197 fauthz->refresh = value; 198 } 199 200 201 static bool 202 qauthz_list_file_prop_get_refresh(Object *obj, 203 Error **errp G_GNUC_UNUSED) 204 { 205 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj); 206 207 return fauthz->refresh; 208 } 209 210 211 static void 212 qauthz_list_file_finalize(Object *obj) 213 { 214 QAuthZListFile *fauthz = QAUTHZ_LIST_FILE(obj); 215 216 object_unref(OBJECT(fauthz->list)); 217 g_free(fauthz->filename); 218 qemu_file_monitor_free(fauthz->file_monitor); 219 } 220 221 222 static void 223 qauthz_list_file_class_init(ObjectClass *oc, void *data) 224 { 225 UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); 226 QAuthZClass *authz = QAUTHZ_CLASS(oc); 227 228 ucc->complete = qauthz_list_file_complete; 229 230 object_class_property_add_str(oc, "filename", 231 qauthz_list_file_prop_get_filename, 232 qauthz_list_file_prop_set_filename); 233 object_class_property_add_bool(oc, "refresh", 234 qauthz_list_file_prop_get_refresh, 235 qauthz_list_file_prop_set_refresh); 236 237 authz->is_allowed = qauthz_list_file_is_allowed; 238 } 239 240 241 static void 242 qauthz_list_file_init(Object *obj) 243 { 244 QAuthZListFile *authz = QAUTHZ_LIST_FILE(obj); 245 246 authz->file_watch = -1; 247 #ifdef CONFIG_INOTIFY1 248 authz->refresh = true; 249 #endif 250 } 251 252 253 QAuthZListFile *qauthz_list_file_new(const char *id, 254 const char *filename, 255 bool refresh, 256 Error **errp) 257 { 258 return QAUTHZ_LIST_FILE( 259 object_new_with_props(TYPE_QAUTHZ_LIST_FILE, 260 object_get_objects_root(), 261 id, errp, 262 "filename", filename, 263 "refresh", refresh ? "yes" : "no", 264 NULL)); 265 } 266 267 268 static const TypeInfo qauthz_list_file_info = { 269 .parent = TYPE_QAUTHZ, 270 .name = TYPE_QAUTHZ_LIST_FILE, 271 .instance_init = qauthz_list_file_init, 272 .instance_size = sizeof(QAuthZListFile), 273 .instance_finalize = qauthz_list_file_finalize, 274 .class_init = qauthz_list_file_class_init, 275 .interfaces = (InterfaceInfo[]) { 276 { TYPE_USER_CREATABLE }, 277 { } 278 } 279 }; 280 281 282 static void 283 qauthz_list_file_register_types(void) 284 { 285 type_register_static(&qauthz_list_file_info); 286 } 287 288 289 type_init(qauthz_list_file_register_types); 290