1 files changed, 139 insertions, 0 deletions
diff --git a/src/utils/common/util_conf.c b/src/utils/common/util_conf.c
new file mode 100644
index 0000000..231f800
--- /dev/null
+++ b/src/utils/common/util_conf.c
@@ -0,0 +1,139 @@
+/*  Copyright (C) 2022 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program 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 General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "utils/common/util_conf.h"
+
+#include "contrib/string.h"
+#include "knot/common/log.h"
+#include "knot/conf/conf.h"
+#include "libknot/attribute.h"
+#include "utils/common/msg.h"
+
+bool util_conf_initialized(void)
+{
+	return (conf() != NULL);
+}
+
+int util_conf_init_confdb(const char *confdb)
+{
+	if (util_conf_initialized()) {
+		ERR2("configuration already initialized");
+		util_conf_deinit();
+		return KNOT_ESEMCHECK;
+	}
+
+	size_t max_conf_size = (size_t)CONF_MAPSIZE * 1024 * 1024;
+
+	conf_flag_t flags = CONF_FNOHOSTNAME | CONF_FOPTMODULES;
+	if (confdb != NULL) {
+		flags |= CONF_FREADONLY;
+	}
+
+	log_init();
+	log_levels_set(LOG_TARGET_STDOUT, LOG_SOURCE_ANY, 0);
+	log_levels_set(LOG_TARGET_STDERR, LOG_SOURCE_ANY, LOG_UPTO(LOG_WARNING));
+	log_levels_set(LOG_TARGET_SYSLOG, LOG_SOURCE_ANY, 0);
+	log_flag_set(LOG_FLAG_NOTIMESTAMP | LOG_FLAG_NOINFO);
+
+	conf_t *new_conf = NULL;
+	int ret = conf_new(&new_conf, conf_schema, confdb, max_conf_size, flags);
+	if (ret != KNOT_EOK) {
+		ERR2("failed opening configuration database '%s' (%s)",
+		     (confdb == NULL ? "" : confdb), knot_strerror(ret));
+	} else {
+		conf_update(new_conf, CONF_UPD_FNONE);
+	}
+	return ret;
+}
+
+int util_conf_init_file(const char *conffile)
+{
+	int ret = util_conf_init_confdb(NULL);
+	if (ret != KNOT_EOK) {
+		return ret;
+	}
+
+	ret = conf_import(conf(), conffile, true, false);
+	if (ret != KNOT_EOK) {
+		ERR2("failed opening configuration file '%s' (%s)",
+		     conffile, knot_strerror(ret));
+	}
+	return ret;
+}
+
+int util_conf_init_justdb(const char *db_type, const char *db_path)
+{
+	int ret = util_conf_init_confdb(NULL);
+	if (ret != KNOT_EOK) {
+		return ret;
+	}
+
+	char *conf_str = sprintf_alloc("database:\n"
+	                               "  storage: .\n"
+	                               "  %s: \"%s\"\n", db_type, db_path);
+	if (conf_str == NULL) {
+		return KNOT_ENOMEM;
+	}
+
+	ret = conf_import(conf(), conf_str, false, false);
+	free(conf_str);
+	if (ret != KNOT_EOK) {
+		ERR2("failed creating temporary configuration (%s)", knot_strerror(ret));
+	}
+	return ret;
+}
+
+int util_conf_init_default(bool allow_db)
+{
+	struct stat st;
+	if (util_conf_initialized()) {
+		return KNOT_EOK;
+	} else if (conf_db_exists(CONF_DEFAULT_DBDIR)) {
+		return util_conf_init_confdb(CONF_DEFAULT_DBDIR);
+	} else if (stat(CONF_DEFAULT_FILE, &st) == 0) {
+		return util_conf_init_file(CONF_DEFAULT_FILE);
+	} else {
+		ERR2("couldn't initialize configuration, please provide %s option",
+		     (allow_db ? "-c, -C, or -D" : "-c or -C"));
+		return KNOT_EINVAL;
+	}
+}
+
+void util_update_privileges(void)
+{
+	int uid, gid;
+	if (conf_user(conf(), &uid, &gid) != KNOT_EOK) {
+		return;
+	}
+
+	// Just try to alter process privileges if different from configured.
+	_unused_ int unused;
+	if ((gid_t)gid != getgid()) {
+		unused = setregid(gid, gid);
+	}
+	if ((uid_t)uid != getuid()) {
+		unused = setreuid(uid, uid);
+	}
+}
+
+void util_conf_deinit(void)
+{
+	log_close();
+	conf_update(NULL, CONF_UPD_FNONE);
+}