listfile.c (7568B)
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);