[PATCH 09/20] uuidd: factor out dropping of privileges into separate function

Petr Uzel
2012-03-29T16:45:42Z

Simplify main by moving dropping of privileges into newly
introduced drop_privileges() function.

Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
---
misc-utils/uuidd.c | 47 +++++++++++++++++++++++++++++------------------
1 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/misc-utils/uuidd.c b/misc-utils/uuidd.c
index aae5dbf..10c3019 100644
--- a/misc-utils/uuidd.c
+++ b/misc-utils/uuidd.c
@@ -486,6 +486,33 @@ socket_ready:
}
}

+/*
+ * Drop privileges of the process
+ *
+ * Set real uid, effective uid and - if supported by the system - also
+ * saved set-user-id. Similarly for gid.
+ *
+ * Exits the program with error upon failure.
+ */
+static void drop_privileges(uid_t uid, gid_t gid)
+{
+#ifdef HAVE_SETRESGID
+ if (setresgid(gid, gid, gid) < 0)
+ err(EXIT_FAILURE, "setresgid");
+#else
+ if (setregid(gid, gid) < 0)
+ err(EXIT_FAILURE, "setregid");
+#endif
+
+#ifdef HAVE_SETRESUID
+ if (setresuid(uid, uid, uid) < 0)
+ err(EXIT_FAILURE, "setresuid");
+#else
+ if (setreuid(uid, uid) < 0)
+ err(EXIT_FAILURE, "setreuid");
+#endif
+}
+
static void __attribute__ ((__noreturn__)) unexpected_size(int size)
{
errx(EXIT_FAILURE, _("Unexpected reply length from server %d"), size);
@@ -501,7 +528,6 @@ int main(int argc, char **argv)
char str[UUID_STR_LEN], *tmp;
uuid_t uu;
uid_t uid;
- gid_t gid;
int i, c, ret;
int debug = 0, do_type = 0, do_kill = 0, num = 0;
int timeout = 0, quiet = 0, drop_privs = 0;
@@ -624,24 +650,9 @@ int main(int argc, char **argv)
"Ignoring --socket\n"));

uid = getuid();
- if (uid && drop_privs) {
- gid = getgid();
-#ifdef HAVE_SETRESGID
- if (setresgid(gid, gid, gid) < 0)
- err(EXIT_FAILURE, "setresgid");
-#else
- if (setregid(gid, gid) < 0)
- err(EXIT_FAILURE, "setregid");
-#endif
+ if (uid && drop_privs)
+ drop_privileges(uid, getgid());

-#ifdef HAVE_SETRESUID
- if (setresuid(uid, uid, uid) < 0)
- err(EXIT_FAILURE, "setresuid");
-#else
- if (setreuid(uid, uid) < 0)
- err(EXIT_FAILURE, "setreuid");
-#endif
- }
if (num && do_type) {
ret = call_daemon(socket_path, do_type + 2, buf,
sizeof(buf), &num, &err_context);
--
1.7.7