pull the config file opening up considerably earlier to fail fast.

parsing is still done in the child, so we can't guarantee success, but if
the file is missing entirely we won't daemonize in that state.

1 files changed, 16 insertions, 14 deletions

diff --git a/usr.sbin/rebound/rebound.c b/usr.sbin/rebound/rebound.c
index 27dda5d4c00..7ab495bd906 100644
--- a/usr.sbin/rebound/rebound.c
+++ b/usr.sbin/rebound/rebound.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: rebound.c,v 1.53 2015/12/04 16:44:20 tedu Exp $ */
+/* $OpenBSD: rebound.c,v 1.54 2015/12/05 10:24:17 tedu Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
  *
@@ -427,7 +427,7 @@ readconfig(FILE *conf, struct sockaddr_storage *remoteaddr)
 }
 
 static int
-launch(const char *confname, int ud, int ld, int kq)
+launch(FILE *conf, int ud, int ld, int kq)
 {
 	struct sockaddr_storage remoteaddr;
 	struct kevent ch[2], kev[4];
@@ -435,16 +435,9 @@ launch(const char *confname, int ud, int ld, int kq)
 	struct request reqkey, *req;
 	struct dnscache *ent;
 	struct passwd *pwd;
-	FILE *conf;
 	int i, r, af;
 	pid_t parent, child;
 
-	conf = fopen(confname, "r");
-	if (!conf) {
-		logmsg(LOG_ERR, "failed to open config %s", confname);
-		return -1;
-	}
-
 	parent = getpid();
 	if (!debug) {
 		if ((child = fork())) {
@@ -478,7 +471,7 @@ launch(const char *confname, int ud, int ld, int kq)
 	af = readconfig(conf, &remoteaddr);
 	fclose(conf);
 	if (af == -1)
-		logerr("failed to read config %s", confname);
+		logerr("parse error in config file");
 
 	EV_SET(&kev[0], ud, EVFILT_READ, EV_ADD, 0, 0, NULL);
 	EV_SET(&kev[1], ld, EVFILT_READ, EV_ADD, 0, 0, NULL);
@@ -627,7 +620,8 @@ main(int argc, char **argv)
 	struct kevent kev;
 	struct rlimit rlim;
 	struct timespec ts, *timeout = NULL;
-	const char *conffile = "/etc/rebound.conf";
+	const char *confname = "/etc/rebound.conf";
+	FILE *conf;
 
 	if (pledge("stdio rpath getpw inet proc id", NULL) == -1)
 		logerr("pledge failed");
@@ -635,7 +629,7 @@ main(int argc, char **argv)
 	while ((ch = getopt(argc, argv, "c:d")) != -1) {
 		switch (ch) {
 		case 'c':
-			conffile = optarg;
+			confname = optarg;
 			break;
 		case 'd':
 			debug = 1;
@@ -693,8 +687,12 @@ main(int argc, char **argv)
 	if (listen(ld, 10) == -1)
 		logerr("listen: %s", strerror(errno));
 
+	conf = fopen(confname, "r");
+	if (!conf)
+		logerr("failed to open config %s", confname);
+
 	if (debug) {
-		launch(conffile, ud, ld, -1);
+		launch(conf, ud, ld, -1);
 		return 1;
 	}
 
@@ -711,7 +709,7 @@ main(int argc, char **argv)
 	while (1) {
 		hupped = 0;
 		childdead = 0;
-		child = launch(conffile, ud, ld, kq);
+		child = launch(conf, ud, ld, kq);
 		if (child == -1)
 			logerr("failed to launch");
 
@@ -735,6 +733,10 @@ main(int argc, char **argv)
 				if (childdead)
 					break;
 				kill(child, SIGHUP);
+				conf = fopen(confname, "r");
+				if (!conf)
+					logerr("failed to open config %s",
+					    confname);
 			} else if (kev.filter == EVFILT_PROC) {
 				/* child died. wait for our own HUP. */
 				logmsg(LOG_INFO, "observed child exit");