diff --git a/unit/test-simutil.c b/unit/test-simutil.c
index 490e288f..b45ae41b 100644
--- a/unit/test-simutil.c
+++ b/unit/test-simutil.c
@@ -496,6 +496,110 @@ static void test_get_2g_path(void)
 	g_assert(!memcmp(path, path1, len));
 }
 
+static void test_auth_build_parse(void)
+{
+	unsigned char auth_cmd[40];
+	const unsigned char rand[16] = { 0x00, 0x01, 0x02, 0x03, 0x04,0x05,
+			0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d,
+			0x0e, 0x0f };
+	const unsigned char sres[4] = { 0x00, 0x11, 0x22, 0x33 };
+	const unsigned char *sres_p;
+	const unsigned char kc[8] = { 0xab, 0xcd, 0xef, 0x12, 0x34, 0x56,
+			0x78, 0x9a };
+	const unsigned char *kc_p;
+	const unsigned char gsm_success[] = { 0x04, 0x00, 0x11, 0x22, 0x33,
+			0x08,0xab, 0xcd, 0xef, 0x12, 0x34, 0x56, 0x78, 0x9a };
+	const unsigned char autn[16] = { 0x0f, 0x0e, 0x0d, 0x0c, 0x0b, 0x0a,
+			0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02,
+			0x01, 0x00 };
+	const unsigned char res[8] = { 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa,
+			0x11, 0x22 };
+	const unsigned char *res_p;
+	const unsigned char ck[16] = { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66,
+			0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff };
+	const unsigned char *ck_p;
+	const unsigned char ik[16] = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd,
+			0xef, 0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10 };
+	const unsigned char *ik_p;
+	const unsigned char auts[16] = { 0xde, 0xea, 0xbe, 0xef, 0xde, 0xea,
+			0xbe, 0xef, 0xde, 0xea, 0xbe, 0xef, 0xde, 0xea,
+			0xbe, 0xef };
+	const unsigned char *auts_p;
+
+	const unsigned char umts_success[] = { 0xdb, 0x08, 0xff, 0xee, 0xdd,
+			0xcc, 0xbb, 0xaa, 0x11, 0x22, 0x10, 0x00, 0x11, 0x22,
+			0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb,
+			0xcc, 0xdd, 0xee, 0xff, 0x10, 0x01, 0x23, 0x45, 0x67,
+			0x89, 0xab, 0xcd, 0xef, 0xfe, 0xdc, 0xba, 0x98, 0x76,
+			0x54, 0x32, 0x10 };
+	const unsigned char umts_success_kc[] = { 0xdb, 0x08, 0xff, 0xee, 0xdd,
+			0xcc, 0xbb, 0xaa, 0x11, 0x22, 0x10, 0x00, 0x11, 0x22,
+			0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb,
+			0xcc, 0xdd, 0xee, 0xff, 0x10, 0x01, 0x23, 0x45, 0x67,
+			0x89, 0xab, 0xcd, 0xef, 0xfe, 0xdc, 0xba, 0x98, 0x76,
+			0x54, 0x32, 0x10, 0x08, 0xab, 0xcd, 0xef, 0x12, 0x34,
+			0x56, 0x78, 0x9a };
+	const unsigned char umts_sync_failure[] = { 0xdc, 0x10, 0xde, 0xea,
+			0xbe, 0xef, 0xde, 0xea, 0xbe, 0xef, 0xde, 0xea, 0xbe,
+			0xef, 0xde, 0xea, 0xbe, 0xef };
+	int len = 0;
+
+	/* test GSM auth command */
+	len = sim_build_gsm_authenticate(auth_cmd, 40, rand);
+
+	g_assert(len == 22);
+	g_assert(auth_cmd[0] == 0x00);
+	g_assert(auth_cmd[1] == 0x88);
+	g_assert(auth_cmd[2] == 0x00);
+	g_assert(auth_cmd[3] == 0x80);
+	g_assert(auth_cmd[4] == 0x11);
+	g_assert(auth_cmd[5] == 0x10);
+	g_assert(!memcmp(auth_cmd + 6, rand, 16));
+
+	/* test UMTS auth command */
+	len = sim_build_umts_authenticate(auth_cmd, 40, rand, autn);
+
+	g_assert(len == 40);
+	g_assert(auth_cmd[0] == 0x00);
+	g_assert(auth_cmd[1] == 0x88);
+	g_assert(auth_cmd[2] == 0x00);
+	g_assert(auth_cmd[3] == 0x81);
+	g_assert(auth_cmd[4] == 0x22);
+	g_assert(auth_cmd[5] == 0x10);
+	g_assert(!memcmp(auth_cmd + 6, rand, 16));
+	g_assert(auth_cmd[22] == 0x10);
+	g_assert(!memcmp(auth_cmd + 23, autn, 16));
+
+	/* test GSM parse */
+	g_assert(sim_parse_gsm_authenticate(gsm_success, sizeof(gsm_success),
+			&sres_p, &kc_p));
+	g_assert(!memcmp(sres_p, sres, 4));
+	g_assert(!memcmp(kc_p, kc, 8));
+
+	/* test UMTS success parse, no kc */
+	g_assert(sim_parse_umts_authenticate(umts_success, sizeof(umts_success),
+			&res_p, &ck_p, &ik_p, &auts_p, &kc_p));
+	g_assert(!memcmp(res_p, res, 8));
+	g_assert(!memcmp(ck_p, ck, 16));
+	g_assert(!memcmp(ik_p, ik, 16));
+	g_assert(!auts_p && !kc_p);
+
+	/* test UMTS sync failure */
+	g_assert(sim_parse_umts_authenticate(umts_sync_failure, sizeof(umts_sync_failure),
+			&res_p, &ck_p, &ik_p, &auts_p, &kc_p));
+	g_assert(!memcmp(auts_p, auts, 16));
+
+	/* test UMTS success parse, with kc */
+	g_assert(sim_parse_umts_authenticate(umts_success_kc, sizeof(umts_success_kc),
+			&res_p, &ck_p, &ik_p, &auts_p, &kc_p));
+	g_assert(!memcmp(res_p, res, 8));
+	g_assert(!memcmp(ck_p, ck, 16));
+	g_assert(!memcmp(ik_p, ik, 16));
+	g_assert(!memcmp(kc_p, kc, 8));
+	g_assert(!auts_p);
+
+}
+
 int main(int argc, char **argv)
 {
 	g_test_init(&argc, &argv, NULL);
@@ -514,6 +618,7 @@ int main(int argc, char **argv)
 			test_application_entry_decode);
 	g_test_add_func("/testsimutil/3G path", test_get_3g_path);
 	g_test_add_func("/testsimutil/2G path", test_get_2g_path);
+	g_test_add_func("/testsimutil/auth build parse", test_auth_build_parse);
 
 	return g_test_run();
 }