Allows execution with suid bit

Allow to call the executable from normal user.
The reset of the environment is for security reasons.

Signed-off-by: Frediano Ziglio <fziglio@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/latency.c b/latency.c
index fab0a8b..1c91761 100644
--- a/latency.c
+++ b/latency.c
@@ -83,8 +83,20 @@ static const unit rate_units[] = {
 int
 main(int argc, char **argv)
 {
+	uid_t ruid = getuid(), euid = geteuid();
+	if (ruid != euid && euid == 0) {
+		clearenv();
+		setenv("HOME", "/root", 1);
+		setenv("PATH", "/sbin:/bin:/usr/sbin:/usr/bin", 1);
+		setenv("SHELL", "/bin/sh", 1);
+		setuid(0);
+	}
+
 	tun_fd = tun_setup();
 
+	if (ruid != euid)
+		setuid(ruid);
+
 	if (argc < 3)
 		usage();