tests/qtest/migration: Add a NULL parameters test for TLS

Make sure the TLS options handling is working correctly with a NULL
parameter. This is relevant due to the usage of StrOrNull for the
tls-creds, tls-authz and tls-hostname options.

With this, all manners of passing TLS options are somehow covered by
the tests, we should not need to do manual testing when touching TLS
options code.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20251215220041.12657-5-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>

tests/qtest/migration/migration-qmp.c

@@ -458,6 +458,15 @@ void migrate_set_parameter_strv(QTestState *who, const char *parameter,
     qtest_qmp_assert_success(who, command, parameter);
 }
 
+void migrate_set_parameter_null(QTestState *who, const char *parameter)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-parameters',"
+                             "'arguments': { %s: null } }",
+                             parameter);
+    migrate_check_parameter_str(who, parameter, "");
+}
+
 static long long migrate_get_parameter_bool(QTestState *who,
                                             const char *parameter)
 {

tests/qtest/migration/migration-qmp.h

@@ -36,6 +36,7 @@ void migrate_set_parameter_str(QTestState *who, const char *parameter,
                                const char *value);
 void migrate_set_parameter_strv(QTestState *who, const char *parameter,
                                 char **strv);
+void migrate_set_parameter_null(QTestState *who, const char *parameter);
 void migrate_set_parameter_bool(QTestState *who, const char *parameter,
                                 int value);
 void migrate_ensure_non_converge(QTestState *who);

tests/qtest/migration/tls-tests.c

@@ -507,6 +507,57 @@ static void test_precopy_tcp_tls_psk_mismatch(void)
     test_precopy_common(&args);
 }
 
+static void *migrate_hook_start_no_tls(QTestState *from, QTestState *to)
+{
+    struct TestMigrateTLSPSKData *data =
+        g_new0(struct TestMigrateTLSPSKData, 1);
+
+    migrate_set_parameter_null(from, "tls-creds");
+    migrate_set_parameter_null(to, "tls-creds");
+
+    return data;
+}
+
+static void test_precopy_tcp_no_tls(void)
+{
+    MigrateCommon args = {
+        .listen_uri = "tcp:127.0.0.1:0",
+        .start_hook = migrate_hook_start_no_tls,
+        .end_hook = migrate_hook_end_tls_psk,
+    };
+
+    test_precopy_common(&args);
+}
+
+static void *
+migrate_hook_start_tls_x509_no_host(QTestState *from, QTestState *to)
+{
+    TestMigrateTLSX509 args = {
+        .verifyclient = true,
+        .clientcert = true,
+        .authzclient = true,
+    };
+    TestMigrateTLSX509Data *data = migrate_hook_start_tls_x509_common(from, to,
+                                                                      &args);
+    migrate_set_parameter_null(from, "tls-hostname");
+    migrate_set_parameter_null(to, "tls-hostname");
+
+    return data;
+}
+
+static void test_precopy_tcp_tls_no_hostname(void)
+{
+    MigrateCommon args = {
+        .listen_uri = "tcp:127.0.0.1:0",
+        .start_hook = migrate_hook_start_tls_x509_no_host,
+        .end_hook = migrate_hook_end_tls_x509,
+        .result = MIG_TEST_FAIL_DEST_QUIT_ERR,
+        .start.hide_stderr = true,
+    };
+
+    test_precopy_common(&args);
+}
+
 #ifdef CONFIG_TASN1
 static void test_precopy_tcp_tls_x509_default_host(void)
 {
@@ -799,6 +850,11 @@ void migration_test_add_tls(MigrationTestEnv *env)
         return;
     }
 
+    migration_test_add("/migration/precopy/tcp/no-tls",
+                       test_precopy_tcp_no_tls);
+    migration_test_add("/migration/precopy/tcp/tls/no-hostname",
+                       test_precopy_tcp_tls_no_hostname);
+
     migration_test_add("/migration/precopy/unix/tls/psk",
                        test_precopy_unix_tls_psk);