test_ipa_subdom_server: Workaround for slow krb5 + SELinux

There is an overhead caused by SELinux after fixing memory leak
in krb5. https://bugzilla.redhat.com/show_bug.cgi?id=1311287.

The overhead is mainly visible with valgrind and moreover
it causes failures due to timeouts.

sh$ time libtool --mode=execute ./test_ipa_subdom_server

enabled/permissive SELinux
real    0m7.976s
user    0m6.680s
sys     0m0.189s

disabled SELinux
real    0m2.111s
user    0m0.071s
sys     0m0.043s

valgrind + enabled/permissive SELinux
real    2m7.310s
user    2m17.080s
sys     0m0.786s

valgrind + disabled SELinux
real    0m5.510s
user    0m3.396s
sys     0m0.309s

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/src/tests/cmocka/test_ipa_subdomains_server.c b/src/tests/cmocka/test_ipa_subdomains_server.c
index 3c40f04e3..0fddc9518 100644
--- a/src/tests/cmocka/test_ipa_subdomains_server.c
+++ b/src/tests/cmocka/test_ipa_subdomains_server.c
@@ -69,6 +69,26 @@
 
 static bool global_rename_called;
 
+#ifdef HAVE_SELINUX
+/* Provide faster implementation of kerberos function
+ * krb5int_labeled_[f]?open. Real functions take care also
+ * about SELinux context which is very expensive operation
+ * and cause failures due to timeout when executing with valgrind.
+ * It's approximately 40 times slower with real function
+ */
+FILE *
+krb5int_labeled_fopen(const char *path, const char *mode)
+{
+    return fopen(path, mode);
+}
+
+int
+krb5int_labeled_open(const char *path, int flags, mode_t mode)
+{
+    return open(path, flags, mode);
+}
+#endif /* HAVE_SELINUX */
+
 krb5_error_code __wrap_krb5_kt_default(krb5_context context, krb5_keytab *id)
 {
     return krb5_kt_resolve(context, KEYTAB_PATH, id);