[PATCH 2/2] selftests/landlock: Create 'listen_zero', 'deny_listen_zero' tests
Ivanov Mikhail
ivanov.mikhail1 at huawei-partners.com
Mon May 13 12:18:32 UTC 2024
4/30/2024 4:36 PM, Mickaël Salaün wrote:
> The subject should be something like:
> "selftests/landlock: Test listening on socket without binding"
thanks, will be fixed.
>
> On Mon, Apr 08, 2024 at 05:47:47PM +0800, Ivanov Mikhail wrote:
>> Suggested code test scenarios where listen(2) call without explicit
>> bind(2) is allowed and forbidden.
>>
>> Signed-off-by: Ivanov Mikhail <ivanov.mikhail1 at huawei-partners.com>
>> Reviewed-by: Konstantin Meskhidze <konstantin.meskhidze at huawei.com>
>> ---
>> tools/testing/selftests/landlock/net_test.c | 89 +++++++++++++++++++++
>> 1 file changed, 89 insertions(+)
>>
>> diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
>> index 936cfc879f1d..6d6b5aef387f 100644
>> --- a/tools/testing/selftests/landlock/net_test.c
>> +++ b/tools/testing/selftests/landlock/net_test.c
>> @@ -1714,6 +1714,95 @@ TEST_F(port_specific, bind_connect_zero)
>> EXPECT_EQ(0, close(bind_fd));
>> }
>>
>> +TEST_F(port_specific, listen_zero)
>> +{
>> + int listen_fd, connect_fd;
>> + uint16_t port;
>> +
>> + /* Adds a rule layer with bind actions. */
>> + if (variant->sandbox == TCP_SANDBOX) {
>> + const struct landlock_ruleset_attr ruleset_attr = {
>> + .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP,
>> + };
>> + const struct landlock_net_port_attr tcp_bind_zero = {
>> + .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP,
>> + .port = 0,
>> + };
>> + int ruleset_fd;
>> +
>> + ruleset_fd = landlock_create_ruleset(&ruleset_attr,
>> + sizeof(ruleset_attr), 0);
>> + ASSERT_LE(0, ruleset_fd);
>> +
>> + /* Checks zero port value on bind action. */
>> + EXPECT_EQ(0,
>> + landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
>> + &tcp_bind_zero, 0));
>> +
>> + enforce_ruleset(_metadata, ruleset_fd);
>> + EXPECT_EQ(0, close(ruleset_fd));
>> + }
>> +
>> + listen_fd = socket_variant(&self->srv0);
>> + ASSERT_LE(0, listen_fd);
>> +
>> + connect_fd = socket_variant(&self->srv0);
>> + ASSERT_LE(0, listen_fd);
>> + /*
>> + * Allow listen(2) to select a random port for the socket,
>> + * since bind(2) wasn't called.
>> + */
>> + EXPECT_EQ(0, listen(listen_fd, backlog));
>> +
>> + /* Sets binded (by listen(2)) port for both protocol families. */
>> + port = get_binded_port(listen_fd, &variant->prot);
>> + EXPECT_NE(0, port);
>> + set_port(&self->srv0, port);
>> +
>> + /* Connects on the binded port. */
>> + EXPECT_EQ(0, connect_variant(connect_fd, &self->srv0));
>> +
>> + EXPECT_EQ(0, close(listen_fd));
>> + EXPECT_EQ(0, close(connect_fd));
>> +}
>> +
>> +TEST_F(port_specific, deny_listen_zero)
>> +{
>> + int listen_fd, ret;
>> +
>> + /* Adds a rule layer with bind actions. */
>> + if (variant->sandbox == TCP_SANDBOX) {
>> + const struct landlock_ruleset_attr ruleset_attr = {
>> + .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP,
>> + };
>> + int ruleset_fd;
>> +
>> + ruleset_fd = landlock_create_ruleset(&ruleset_attr,
>> + sizeof(ruleset_attr), 0);
>> + ASSERT_LE(0, ruleset_fd);
>> +
>> + /* Forbid binding to any port. */
>> + enforce_ruleset(_metadata, ruleset_fd);
>> + EXPECT_EQ(0, close(ruleset_fd));
>> + }
>> +
>> + listen_fd = socket_variant(&self->srv0);
>> + ASSERT_LE(0, listen_fd);
>> + /*
>
> nit: Extra space
will be fixed
>
>> + * Check that listen(2) call is prohibited without first calling bind(2).
>
> This should fit in 80 columns.
will be fixed
>
>> + */
>> + ret = listen(listen_fd, backlog);
>> + if (is_restricted(&variant->prot, variant->sandbox)) {
>> + /* Denied by Landlock. */
>> + EXPECT_NE(0, ret);
>> + EXPECT_EQ(EACCES, errno);
>> + } else {
>> + EXPECT_EQ(0, ret);
>> + }
>> +
>> + EXPECT_EQ(0, close(listen_fd));
>> +}
>
> These tests look good!
>
>> +
>> TEST_F(port_specific, bind_connect_1023)
>> {
>> int bind_fd, connect_fd, ret;
>> --
>> 2.34.1
>>
>>
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