capabilities: Add support for securebits flags

This adds securebits flags for start-stop-daemon and supervise-daemon
by adding --secbits option. As a result, the user can specify
securebits the program should run with. see capabilities(7)

man/start-stop-daemon.8

@@ -164,6 +164,10 @@ log it or send it to another location.
 .It Fl -capabilities Ar cap-list
 Start the daemon with the listed inheritable, ambient and bounding capabilities.
 The format is the same as in cap_iab(3).
+.It Fl -secbits Ar sec-bits
+Set the security-bits for the program.
+The numeric value of the security-bits can be found in <sys/secbits.h> header file.
+The format is the same as in strtoul(3).
 .It Fl w , -wait Ar milliseconds
 Wait
 .Ar milliseconds

man/supervise-daemon.8

@@ -161,6 +161,10 @@ but with the standard error output.
 .It Fl -capabilities Ar cap-list
 Start the daemon with the listed inheritable, ambient and bounding capabilities.
 The format is the same as in cap_iab(3).
+.It Fl -secbits Ar sec-bits
+Set the security-bits for the program.
+The numeric value of the security-bits can be found in <sys/secbits.h> header file.
+The format is the same as in strtoul(3).
 .El
 .Sh ENVIRONMENT
 .Va SSD_IONICELEVEL

sh/start-stop-daemon.sh

@@ -54,6 +54,7 @@ ssd_start()
 		${output_logger_arg} \
 		${error_logger_arg} \
 		${capabilities+--capabilities} "$capabilities" \
+		${secbits:+--secbits} "$secbits" \
 		${procname:+--name} $procname \
 		${pidfile:+--pidfile} $pidfile \
 		${command_user+--user} $command_user \

sh/supervise-daemon.sh

@@ -37,6 +37,7 @@ supervise_start()
 		${healthcheck_delay:+--healthcheck-delay} $healthcheck_delay \
 		${healthcheck_timer:+--healthcheck-timer} $healthcheck_timer \
 		${capabilities+--capabilities} "$capabilities" \
+		${secbits:+--secbits} "$secbits" \
 		${command_user+--user} $command_user \
 		${umask+--umask} $umask \
 		${supervise_daemon_args:-${start_stop_daemon_args}} \

src/rc/start-stop-daemon.c

@@ -74,6 +74,7 @@ const char getoptstring[] = "I:KN:PR:Sa:bc:d:e:g:ik:mn:op:s:tu:r:w:x:1:2:3:4:" \
 	getoptstring_COMMON;
 const struct option longopts[] = {
 	{ "capabilities", 1, NULL, 0x100},
+	{ "secbits",      1, NULL, 0x101},
 	{ "ionice",       1, NULL, 'I'},
 	{ "stop",         0, NULL, 'K'},
 	{ "nicelevel",    1, NULL, 'N'},
@@ -107,6 +108,7 @@ const struct option longopts[] = {
 };
 const char * const longopts_help[] = {
 	"Set the inheritable, ambient and bounding capabilities",
+	"Set the security-bits for the program",
 	"Set an ionice class:data when starting",
 	"Stop daemon",
 	"Set a nicelevel when starting",
@@ -315,6 +317,7 @@ int main(int argc, char **argv)
 	unsigned int start_wait = 0;
 #ifdef HAVE_CAP
 	cap_iab_t cap_iab = NULL;
+	unsigned secbits = 0;
 #endif
 
 	applet = basename_c(argv[0]);
@@ -372,6 +375,21 @@ int main(int argc, char **argv)
 #endif
 			break;
 
+		case 0x101:
+#ifdef HAVE_CAP
+			if (*optarg == '\0')
+				eerrorx("Secbits are empty");
+
+			tmp = NULL;
+			secbits = strtoul(optarg, &tmp, 0);
+			if (*tmp != '\0')
+				eerrorx("Could not parse secbits: invalid char %c", *tmp);
+#else
+			eerrorx("Capabilities support not enabled");
+#endif
+			break;
+
+
 		case 'I': /* --ionice */
 			if (sscanf(optarg, "%d:%d", &ionicec, &ioniced) == 0)
 				eerrorx("%s: invalid ionice `%s'",
@@ -890,6 +908,11 @@ int main(int argc, char **argv)
 			if (i != 0)
 				eerrorx("Could not set iab: %s", strerror(errno));
 		}
+
+		if (secbits != 0) {
+			if (cap_set_secbits(secbits) < 0)
+				eerrorx("Could not set securebits to 0x%x: %s", secbits, strerror(errno));
+		}
 #endif
 
 #ifdef TIOCNOTTY

src/rc/supervise-daemon.c

@@ -78,6 +78,7 @@ const struct option longopts[] = {
 	{ "healthcheck-timer",        1, NULL, 'a'},
 	{ "healthcheck-delay",        1, NULL, 'A'},
 	{ "capabilities", 1, NULL, 0x100},
+	{ "secbits", 1, NULL, 0x101},
 	{ "respawn-delay",        1, NULL, 'D'},
 	{ "chdir",        1, NULL, 'd'},
 	{ "env",          1, NULL, 'e'},
@@ -104,6 +105,7 @@ const char * const longopts_help[] = {
 	"set an initial health check delay",
 	"set a health check timer",
 	"Set the inheritable, ambient and bounding capabilities",
+	"Set the security-bits for the program",
 	"Set a respawn delay",
 	"Change the PWD",
 	"Set an environment string",
@@ -160,6 +162,7 @@ static char *svcname = NULL;
 static bool verbose = false;
 #ifdef HAVE_CAP
 static cap_iab_t cap_iab = NULL;
+static unsigned secbits = 0;
 #endif
 
 extern char **environ;
@@ -427,6 +430,11 @@ static void child_process(char *exec, char **argv)
 		if (i != 0)
 			eerrorx("Could not set iab: %s", strerror(errno));
 	}
+
+	if (secbits != 0) {
+		if (cap_set_secbits(secbits) < 0)
+			eerrorx("Could not set securebits to 0x%x: %s", secbits, strerror(errno));
+	}
 #endif
 
 	/* remove the controlling tty */
@@ -832,6 +840,20 @@ int main(int argc, char **argv)
 #endif
 			break;
 
+        case 0x101:
+#ifdef HAVE_CAP
+			if (*optarg == '\0')
+				eerrorx("Secbits are empty");
+
+			tmp = NULL;
+			secbits = strtoul(optarg, &tmp, 0);
+			if (*tmp != '\0')
+				eerrorx("Could not parse secbits: invalid char %c", *tmp);
+#else
+			eerrorx("Capabilities support not enabled");
+#endif
+			break;
+
 		case 'D':  /* --respawn-delay time */
 			n = sscanf(optarg, "%d", &respawn_delay);
 			if (n	!= 1 || respawn_delay < 1)