Extract another couple of chunks from main() into helper functions,

get_routefd() and set_user().

1 files changed, 51 insertions, 33 deletions

diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c
index 05760697a75..3238da5a7b2 100644
--- a/sbin/dhclient/dhclient.c
+++ b/sbin/dhclient/dhclient.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhclient.c,v 1.687 2020/11/27 14:52:36 krw Exp $	*/
+/*	$OpenBSD: dhclient.c,v 1.688 2020/12/01 14:55:40 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -118,8 +118,10 @@ void		 get_name(struct interface_info *, int, char *);
 void		 get_address(struct interface_info *);
 void		 get_ssid(struct interface_info *, int);
 void		 get_sockets(struct interface_info *);
+int		 get_routefd(int);
 void		 set_autoconf(struct interface_info *, int);
 void		 set_iff_up(struct interface_info *, int);
+void		 set_user(char *);
 int		 get_ifa_family(char *, int);
 struct ifaddrs	*get_link_ifa(const char *, struct ifaddrs *);
 void		 interface_state(struct interface_info *);
@@ -413,6 +415,29 @@ set_iff_up(struct interface_info *ifi, int ioctlfd)
 }
 
 void
+set_user(char *user)
+{
+	struct passwd		*pw;
+
+	pw = getpwnam(user);
+	if (pw == NULL)
+		fatalx("no such user: %s", user);
+
+	if (chroot(pw->pw_dir) == -1)
+		fatal("chroot(%s)", pw->pw_dir);
+	if (chdir("/") == -1)
+		fatal("chdir(\"/\")");
+	if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
+		fatal("setresgid");
+	if (setgroups(1, &pw->pw_gid) == -1)
+		fatal("setgroups");
+	if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
+		fatal("setresuid");
+
+	endpwent();
+}
+
+void
 get_sockets(struct interface_info *ifi)
 {
 	unsigned char		*newp;
@@ -430,6 +455,28 @@ get_sockets(struct interface_info *ifi)
 	}
 }
 
+int
+get_routefd(int rdomain)
+{
+	int		routefd, rtfilter;
+
+	if ((routefd = socket(AF_ROUTE, SOCK_RAW, AF_INET)) == -1)
+		fatal("socket(AF_ROUTE, SOCK_RAW)");
+
+	rtfilter = ROUTE_FILTER(RTM_PROPOSAL) | ROUTE_FILTER(RTM_IFINFO) |
+	    ROUTE_FILTER(RTM_NEWADDR) | ROUTE_FILTER(RTM_DELADDR) |
+	    ROUTE_FILTER(RTM_IFANNOUNCE) | ROUTE_FILTER(RTM_80211INFO);
+
+	if (setsockopt(routefd, AF_ROUTE, ROUTE_MSGFILTER,
+	    &rtfilter, sizeof(rtfilter)) == -1)
+		fatal("setsockopt(ROUTE_MSGFILTER)");
+	if (setsockopt(routefd, AF_ROUTE, ROUTE_TABLEFILTER, &rdomain,
+	    sizeof(rdomain)) == -1)
+		fatal("setsockopt(ROUTE_TABLEFILTER)");
+
+	return routefd;
+}
+
 void
 routefd_handler(struct interface_info *ifi, int routefd)
 {
@@ -578,10 +625,9 @@ main(int argc, char *argv[])
 {
 	struct stat		 sb;
 	struct interface_info	*ifi;
-	struct passwd		*pw;
 	char			*ignore_list = NULL;
 	int			 fd, socket_fd[2];
-	int			 rtfilter, routefd;
+	int			 routefd;
 	int			 ch;
 
 	if (isatty(STDERR_FILENO) != 0)
@@ -684,26 +730,10 @@ main(int argc, char *argv[])
 	if ((cmd_opts & OPT_NOACTION) != 0)
 		return 0;
 
-	if ((pw = getpwnam("_dhcp")) == NULL)
-		fatalx("no such user: _dhcp");
-
 	if (asprintf(&path_lease_db, "%s.%s", _PATH_LEASE_DB, ifi->name) == -1)
 		fatal("path_lease_db");
 
-	if ((routefd = socket(AF_ROUTE, SOCK_RAW, AF_INET)) == -1)
-		fatal("socket(AF_ROUTE, SOCK_RAW)");
-
-	rtfilter = ROUTE_FILTER(RTM_PROPOSAL) | ROUTE_FILTER(RTM_IFINFO) |
-	    ROUTE_FILTER(RTM_NEWADDR) | ROUTE_FILTER(RTM_DELADDR) |
-	    ROUTE_FILTER(RTM_IFANNOUNCE) | ROUTE_FILTER(RTM_80211INFO);
-
-	if (setsockopt(routefd, AF_ROUTE, ROUTE_MSGFILTER,
-	    &rtfilter, sizeof(rtfilter)) == -1)
-		fatal("setsockopt(ROUTE_MSGFILTER)");
-	if (setsockopt(routefd, AF_ROUTE, ROUTE_TABLEFILTER, &ifi->rdomain,
-	    sizeof(ifi->rdomain)) == -1)
-		fatal("setsockopt(ROUTE_TABLEFILTER)");
-
+	routefd = get_routefd(ifi->rdomain);
 	fd = take_charge(ifi, routefd, path_lease_db);
 	if (fd != -1)
 		read_lease_db(&ifi->lease_db);
@@ -712,19 +742,7 @@ main(int argc, char *argv[])
 		log_warn("%s: fopen(%s)", log_procname, path_lease_db);
 	write_lease_db(&ifi->lease_db);
 
-	if (chroot(pw->pw_dir) == -1)
-		fatal("chroot(%s)", pw->pw_dir);
-	if (chdir("/") == -1)
-		fatal("chdir(\"/\")");
-
-	if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
-		fatal("setresgid");
-	if (setgroups(1, &pw->pw_gid) == -1)
-		fatal("setgroups");
-	if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
-		fatal("setresuid");
-
-	endpwent();
+	set_user("_dhcp");
 
 	if ((cmd_opts & OPT_FOREGROUND) == 0) {
 		if (pledge("stdio inet dns route proc", NULL) == -1)