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+/*
+ * llmnrd -- LLMNR (RFC 4705) responder daemon.
+ *
+ * Copyright (C) 2014-2015 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * This file is part of llmnrd.
+ *
+ * llmnrd 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, version 2 of the License.
+ *
+ * llmnrd 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 llmnrd. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <getopt.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/ioctl.h>
+
+#include "compiler.h"
+#include "log.h"
+#include "util.h"
+
+#include "iface.h"
+#include "llmnr.h"
+#include "llmnr-packet.h"
+
+static const char *short_opts = "H:p:dh";
+static const struct option long_opts[] = {
+ { "hostname", required_argument, NULL, 'H' },
+ { "port", required_argument, NULL, 'p' },
+ { "daemonize", no_argument, NULL, 'd' },
+ { "help", no_argument, NULL, 'h' },
+ { NULL, 0, NULL, 0 },
+};
+
+static void __noreturn usage_and_exit(int status)
+{
+ fprintf(stdout, "Usage: llmnrd [OPTIONS]\n"
+ "Options:\n"
+ " -H, --hostname <name> set hostname to respond with (default: system hostname)\n"
+ " -p, --port <number> set port number to listen on (default: %d)\n"
+ " -d, --daemonize run as daemon in the background\n"
+ " -h, --help show this help and exit\n",
+ LLMNR_UDP_PORT);
+ exit(status);
+}
+
+static void signal_handler(int sig)
+{
+ switch (sig) {
+ case SIGINT:
+ case SIGQUIT:
+ case SIGTERM:
+ log_info("Interrupt received. Stopping llmnrd.\n");
+ iface_stop();
+ llmnr_stop();
+ break;
+ case SIGHUP:
+ default:
+ /* ignore */
+ break;
+ }
+}
+
+static void register_signal(int sig, void (*handler)(int))
+{
+ sigset_t block_mask;
+ struct sigaction saction;
+
+ sigfillset(&block_mask);
+
+ saction.sa_handler = handler;
+ saction.sa_mask = block_mask;
+
+ if (sigaction(sig, &saction, NULL) != 0) {
+ log_err("Failed to register signal handler for %s (%d)\n",
+ strsignal(sig), sig);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ int c, ret = EXIT_FAILURE;
+ long num_arg;
+ bool daemonize = false;
+ char *hostname = "";
+ uint16_t port = LLMNR_UDP_PORT;
+
+ while ((c = getopt_long(argc, argv, short_opts, long_opts, NULL)) != -1) {
+ switch (c) {
+ case 'd':
+ daemonize = true;
+ break;
+ case 'H':
+ hostname = xstrdup(optarg);
+ break;
+ case 'p':
+ num_arg = strtol(optarg, NULL, 0);
+ if (num_arg < 0 || num_arg > UINT16_MAX) {
+ log_err("Invalid port number: %ld\n", num_arg);
+ return EXIT_FAILURE;
+ }
+ port = num_arg;
+ case 'h':
+ ret = EXIT_SUCCESS;
+ /* fall through */
+ default:
+ usage_and_exit(ret);
+ }
+ }
+
+ register_signal(SIGINT, signal_handler);
+ register_signal(SIGQUIT, signal_handler);
+ register_signal(SIGTERM, signal_handler);
+ register_signal(SIGHUP, signal_handler);
+
+ if (hostname[0] == '\0') {
+ /* TODO: Consider hostname changing at runtime */
+ hostname = xmalloc(255);
+ if (gethostname(hostname, 255) != 0) {
+ log_err("Failed to get hostname");
+ return EXIT_FAILURE;
+ }
+ }
+
+ if (daemonize) {
+ /* TODO */
+ }
+
+ if (iface_start_thread() < 0)
+ goto out;
+
+ ret = llmnr_run(hostname, port);
+out:
+ free(hostname);
+ return ret;
+}