[RFC PATCH v2 3/9] selftests/landlock: Support LANDLOCK_ACCESS_NET_LISTEN_TCP
Günther Noack
gnoack at google.com
Mon Aug 19 21:53:44 UTC 2024
Some comment nits I forgot, see below.
On Wed, Aug 14, 2024 at 11:01:45AM +0800, Mikhail Ivanov wrote:
> * Add listen_variant() to simplify listen(2) return code checking.
> * Rename test_bind_and_connect() to test_restricted_net_fixture().
> * Extend current net rules with LANDLOCK_ACCESS_NET_LISTEN_TCP access.
> * Rename test port_specific.bind_connect_1023 to
> port_specific.port_1023.
> * Check little endian port restriction for listen in
> ipv4_tcp.port_endianness.
> * Some local renames and comment changes.
>
> Signed-off-by: Mikhail Ivanov <ivanov.mikhail1 at huawei-partners.com>
> ---
> tools/testing/selftests/landlock/net_test.c | 198 +++++++++++---------
> 1 file changed, 107 insertions(+), 91 deletions(-)
>
> diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
> index f21cfbbc3638..8126f5c0160f 100644
> --- a/tools/testing/selftests/landlock/net_test.c
> +++ b/tools/testing/selftests/landlock/net_test.c
> @@ -2,7 +2,7 @@
> /*
> * Landlock tests - Network
> *
> - * Copyright © 2022-2023 Huawei Tech. Co., Ltd.
> + * Copyright © 2022-2024 Huawei Tech. Co., Ltd.
> * Copyright © 2023 Microsoft Corporation
> */
>
> @@ -22,6 +22,17 @@
>
> #include "common.h"
>
> +/* clang-format off */
> +
> +#define ACCESS_LAST LANDLOCK_ACCESS_NET_LISTEN_TCP
> +
> +#define ACCESS_ALL ( \
> + LANDLOCK_ACCESS_NET_BIND_TCP | \
> + LANDLOCK_ACCESS_NET_CONNECT_TCP | \
> + LANDLOCK_ACCESS_NET_LISTEN_TCP)
> +
> +/* clang-format on */
> +
> const short sock_port_start = (1 << 10);
>
> static const char loopback_ipv4[] = "127.0.0.1";
> @@ -282,6 +293,16 @@ static int connect_variant(const int sock_fd,
> return connect_variant_addrlen(sock_fd, srv, get_addrlen(srv, false));
> }
>
> +static int listen_variant(const int sock_fd, const int backlog)
> +{
> + int ret;
> +
> + ret = listen(sock_fd, backlog);
> + if (ret < 0)
> + return -errno;
> + return ret;
> +}
> +
> FIXTURE(protocol)
> {
> struct service_fixture srv0, srv1, srv2, unspec_any0, unspec_srv0;
> @@ -438,9 +459,11 @@ FIXTURE_VARIANT_ADD(protocol, tcp_sandbox_with_unix_datagram) {
> },
> };
>
> -static void test_bind_and_connect(struct __test_metadata *const _metadata,
> - const struct service_fixture *const srv,
> - const bool deny_bind, const bool deny_connect)
> +static void test_restricted_net_fixture(struct __test_metadata *const _metadata,
> + const struct service_fixture *const srv,
> + const bool deny_bind,
> + const bool deny_connect,
> + const bool deny_listen)
> {
> char buf = '\0';
> int inval_fd, bind_fd, client_fd, status, ret;
> @@ -512,8 +535,14 @@ static void test_bind_and_connect(struct __test_metadata *const _metadata,
> EXPECT_EQ(0, ret);
>
> /* Creates a listening socket. */
> - if (srv->protocol.type == SOCK_STREAM)
> - EXPECT_EQ(0, listen(bind_fd, backlog));
> + if (srv->protocol.type == SOCK_STREAM) {
> + ret = listen_variant(bind_fd, backlog);
> + if (deny_listen) {
> + EXPECT_EQ(-EACCES, ret);
> + } else {
> + EXPECT_EQ(0, ret);
> + }
> + }
> }
>
> child = fork();
> @@ -530,7 +559,7 @@ static void test_bind_and_connect(struct __test_metadata *const _metadata,
> ret = connect_variant(connect_fd, srv);
> if (deny_connect) {
> EXPECT_EQ(-EACCES, ret);
> - } else if (deny_bind) {
> + } else if (deny_bind || deny_listen) {
> /* No listening server. */
> EXPECT_EQ(-ECONNREFUSED, ret);
> } else {
> @@ -545,7 +574,7 @@ static void test_bind_and_connect(struct __test_metadata *const _metadata,
>
> /* Accepts connection from the child. */
> client_fd = bind_fd;
> - if (!deny_bind && !deny_connect) {
> + if (!deny_bind && !deny_connect && !deny_listen) {
> if (srv->protocol.type == SOCK_STREAM) {
> client_fd = accept(bind_fd, NULL, 0);
> ASSERT_LE(0, client_fd);
> @@ -571,16 +600,15 @@ TEST_F(protocol, bind)
> {
> if (variant->sandbox == TCP_SANDBOX) {
> const struct landlock_ruleset_attr ruleset_attr = {
> - .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + .handled_access_net = ACCESS_ALL,
> };
> - const struct landlock_net_port_attr tcp_bind_connect_p0 = {
> - .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr tcp_not_restricted_p0 = {
> + .allowed_access = ACCESS_ALL,
> .port = self->srv0.port,
> };
> - const struct landlock_net_port_attr tcp_connect_p1 = {
> - .allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr tcp_denied_bind_p1 = {
> + .allowed_access = ACCESS_ALL &
> + ~LANDLOCK_ACCESS_NET_BIND_TCP,
> .port = self->srv1.port,
> };
> int ruleset_fd;
> @@ -589,48 +617,47 @@ TEST_F(protocol, bind)
> sizeof(ruleset_attr), 0);
> ASSERT_LE(0, ruleset_fd);
>
> - /* Allows connect and bind for the first port. */
> + /* Allows all actions for the first port. */
> ASSERT_EQ(0,
> landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &tcp_bind_connect_p0, 0));
> + &tcp_not_restricted_p0, 0));
>
> - /* Allows connect and denies bind for the second port. */
> + /* Allows all actions despite bind. */
s/despite/except/ would be more conventional English, I believe.
> ASSERT_EQ(0,
> landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &tcp_connect_p1, 0));
> + &tcp_denied_bind_p1, 0));
>
> enforce_ruleset(_metadata, ruleset_fd);
> EXPECT_EQ(0, close(ruleset_fd));
> }
> + bool restricted = is_restricted(&variant->prot, variant->sandbox);
>
> /* Binds a socket to the first port. */
> - test_bind_and_connect(_metadata, &self->srv0, false, false);
> + test_restricted_net_fixture(_metadata, &self->srv0, false, false,
> + false);
>
> /* Binds a socket to the second port. */
> - test_bind_and_connect(_metadata, &self->srv1,
> - is_restricted(&variant->prot, variant->sandbox),
> - false);
> + test_restricted_net_fixture(_metadata, &self->srv1, restricted, false,
> + false);
>
> /* Binds a socket to the third port. */
> - test_bind_and_connect(_metadata, &self->srv2,
> - is_restricted(&variant->prot, variant->sandbox),
> - is_restricted(&variant->prot, variant->sandbox));
> + test_restricted_net_fixture(_metadata, &self->srv2, restricted,
> + restricted, restricted);
> }
>
> TEST_F(protocol, connect)
> {
> if (variant->sandbox == TCP_SANDBOX) {
> const struct landlock_ruleset_attr ruleset_attr = {
> - .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + .handled_access_net = ACCESS_ALL,
> };
> - const struct landlock_net_port_attr tcp_bind_connect_p0 = {
> - .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr tcp_not_restricted_p0 = {
> + .allowed_access = ACCESS_ALL,
> .port = self->srv0.port,
> };
> - const struct landlock_net_port_attr tcp_bind_p1 = {
> - .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP,
> + const struct landlock_net_port_attr tcp_denied_connect_p1 = {
> + .allowed_access = ACCESS_ALL &
> + ~LANDLOCK_ACCESS_NET_CONNECT_TCP,
> .port = self->srv1.port,
> };
> int ruleset_fd;
> @@ -639,28 +666,27 @@ TEST_F(protocol, connect)
> sizeof(ruleset_attr), 0);
> ASSERT_LE(0, ruleset_fd);
>
> - /* Allows connect and bind for the first port. */
> + /* Allows all actions for the first port. */
> ASSERT_EQ(0,
> landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &tcp_bind_connect_p0, 0));
> + &tcp_not_restricted_p0, 0));
>
> - /* Allows bind and denies connect for the second port. */
> + /* Allows all actions despite connect. */
Same here.
> ASSERT_EQ(0,
> landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &tcp_bind_p1, 0));
> + &tcp_denied_connect_p1, 0));
>
> enforce_ruleset(_metadata, ruleset_fd);
> EXPECT_EQ(0, close(ruleset_fd));
> }
> -
> - test_bind_and_connect(_metadata, &self->srv0, false, false);
> -
> - test_bind_and_connect(_metadata, &self->srv1, false,
> - is_restricted(&variant->prot, variant->sandbox));
> -
> - test_bind_and_connect(_metadata, &self->srv2,
> - is_restricted(&variant->prot, variant->sandbox),
> - is_restricted(&variant->prot, variant->sandbox));
> + bool restricted = is_restricted(&variant->prot, variant->sandbox);
> +
> + test_restricted_net_fixture(_metadata, &self->srv0, false, false,
> + false);
> + test_restricted_net_fixture(_metadata, &self->srv1, false, restricted,
> + false);
> + test_restricted_net_fixture(_metadata, &self->srv2, restricted,
> + restricted, restricted);
> }
>
> TEST_F(protocol, bind_unspec)
> @@ -761,7 +787,7 @@ TEST_F(protocol, connect_unspec)
> ASSERT_LE(0, bind_fd);
> EXPECT_EQ(0, bind_variant(bind_fd, &self->srv0));
> if (self->srv0.protocol.type == SOCK_STREAM)
> - EXPECT_EQ(0, listen(bind_fd, backlog));
> + EXPECT_EQ(0, listen_variant(bind_fd, backlog));
>
> child = fork();
> ASSERT_LE(0, child);
> @@ -1127,8 +1153,8 @@ TEST_F(tcp_layers, ruleset_overlap)
> * Forbids to connect to the socket because only one ruleset layer
> * allows connect.
> */
> - test_bind_and_connect(_metadata, &self->srv0, false,
> - variant->num_layers >= 2);
> + test_restricted_net_fixture(_metadata, &self->srv0, false,
> + variant->num_layers >= 2, false);
> }
>
> TEST_F(tcp_layers, ruleset_expand)
> @@ -1208,11 +1234,12 @@ TEST_F(tcp_layers, ruleset_expand)
> EXPECT_EQ(0, close(ruleset_fd));
> }
>
> - test_bind_and_connect(_metadata, &self->srv0, false,
> - variant->num_layers >= 3);
> + test_restricted_net_fixture(_metadata, &self->srv0, false,
> + variant->num_layers >= 3, false);
>
> - test_bind_and_connect(_metadata, &self->srv1, variant->num_layers >= 1,
> - variant->num_layers >= 2);
> + test_restricted_net_fixture(_metadata, &self->srv1,
> + variant->num_layers >= 1,
> + variant->num_layers >= 2, false);
> }
>
> /* clang-format off */
> @@ -1230,16 +1257,6 @@ FIXTURE_TEARDOWN(mini)
> {
> }
>
> -/* clang-format off */
> -
> -#define ACCESS_LAST LANDLOCK_ACCESS_NET_CONNECT_TCP
> -
> -#define ACCESS_ALL ( \
> - LANDLOCK_ACCESS_NET_BIND_TCP | \
> - LANDLOCK_ACCESS_NET_CONNECT_TCP)
> -
> -/* clang-format on */
> -
> TEST_F(mini, network_access_rights)
> {
> const struct landlock_ruleset_attr ruleset_attr = {
> @@ -1454,8 +1471,9 @@ TEST_F(mini, tcp_port_overflow)
>
> enforce_ruleset(_metadata, ruleset_fd);
>
> - test_bind_and_connect(_metadata, &srv_denied, true, true);
> - test_bind_and_connect(_metadata, &srv_max_allowed, false, false);
> + test_restricted_net_fixture(_metadata, &srv_denied, true, true, false);
> + test_restricted_net_fixture(_metadata, &srv_max_allowed, false, false,
> + false);
> }
>
> FIXTURE(ipv4_tcp)
> @@ -1485,22 +1503,21 @@ FIXTURE_TEARDOWN(ipv4_tcp)
> TEST_F(ipv4_tcp, port_endianness)
> {
> const struct landlock_ruleset_attr ruleset_attr = {
> - .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + .handled_access_net = ACCESS_ALL,
> };
> const struct landlock_net_port_attr bind_host_endian_p0 = {
> .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP,
> /* Host port format. */
> .port = self->srv0.port,
> };
> - const struct landlock_net_port_attr connect_big_endian_p0 = {
> - .allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr connect_listen_big_endian_p0 = {
> + .allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP |
> + LANDLOCK_ACCESS_NET_LISTEN_TCP,
> /* Big endian port format. */
> .port = htons(self->srv0.port),
> };
> - const struct landlock_net_port_attr bind_connect_host_endian_p1 = {
> - .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr not_restricted_host_endian_p1 = {
> + .allowed_access = ACCESS_ALL,
> /* Host port format. */
> .port = self->srv1.port,
> };
> @@ -1514,16 +1531,18 @@ TEST_F(ipv4_tcp, port_endianness)
> ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> &bind_host_endian_p0, 0));
> ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &connect_big_endian_p0, 0));
> + &connect_listen_big_endian_p0, 0));
> ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &bind_connect_host_endian_p1, 0));
> + ¬_restricted_host_endian_p1, 0));
> enforce_ruleset(_metadata, ruleset_fd);
>
> /* No restriction for big endinan CPU. */
> - test_bind_and_connect(_metadata, &self->srv0, false, little_endian);
> + test_restricted_net_fixture(_metadata, &self->srv0, false,
> + little_endian, little_endian);
>
> /* No restriction for any CPU. */
> - test_bind_and_connect(_metadata, &self->srv1, false, false);
> + test_restricted_net_fixture(_metadata, &self->srv1, false, false,
> + false);
> }
>
> TEST_F(ipv4_tcp, with_fs)
> @@ -1691,7 +1710,7 @@ TEST_F(port_specific, bind_connect_zero)
> ret = bind_variant(bind_fd, &self->srv0);
> EXPECT_EQ(0, ret);
>
> - EXPECT_EQ(0, listen(bind_fd, backlog));
> + EXPECT_EQ(0, listen_variant(bind_fd, backlog));
>
> /* Connects on port 0. */
> ret = connect_variant(connect_fd, &self->srv0);
> @@ -1714,26 +1733,23 @@ TEST_F(port_specific, bind_connect_zero)
> EXPECT_EQ(0, close(bind_fd));
> }
>
> -TEST_F(port_specific, bind_connect_1023)
> +TEST_F(port_specific, port_1023)
> {
> int bind_fd, connect_fd, ret;
>
> - /* Adds a rule layer with bind and connect actions. */
> + /* Adds a rule layer with all actions. */
> if (variant->sandbox == TCP_SANDBOX) {
> const struct landlock_ruleset_attr ruleset_attr = {
> - .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP
> + .handled_access_net = ACCESS_ALL
> };
> /* A rule with port value less than 1024. */
> - const struct landlock_net_port_attr tcp_bind_connect_low_range = {
> - .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr tcp_low_range_port = {
> + .allowed_access = ACCESS_ALL,
> .port = 1023,
> };
> /* A rule with 1024 port. */
> - const struct landlock_net_port_attr tcp_bind_connect = {
> - .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
> - LANDLOCK_ACCESS_NET_CONNECT_TCP,
> + const struct landlock_net_port_attr tcp_port_1024 = {
> + .allowed_access = ACCESS_ALL,
> .port = 1024,
> };
> int ruleset_fd;
> @@ -1744,10 +1760,10 @@ TEST_F(port_specific, bind_connect_1023)
>
> ASSERT_EQ(0,
> landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &tcp_bind_connect_low_range, 0));
> + &tcp_low_range_port, 0));
> ASSERT_EQ(0,
> landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> - &tcp_bind_connect, 0));
> + &tcp_port_1024, 0));
>
> enforce_ruleset(_metadata, ruleset_fd);
> EXPECT_EQ(0, close(ruleset_fd));
> @@ -1771,7 +1787,7 @@ TEST_F(port_specific, bind_connect_1023)
> ret = bind_variant(bind_fd, &self->srv0);
> clear_cap(_metadata, CAP_NET_BIND_SERVICE);
> EXPECT_EQ(0, ret);
> - EXPECT_EQ(0, listen(bind_fd, backlog));
> + EXPECT_EQ(0, listen_variant(bind_fd, backlog));
>
> /* Connects on the binded port 1023. */
> ret = connect_variant(connect_fd, &self->srv0);
> @@ -1791,7 +1807,7 @@ TEST_F(port_specific, bind_connect_1023)
> /* Binds on port 1024. */
> ret = bind_variant(bind_fd, &self->srv0);
> EXPECT_EQ(0, ret);
> - EXPECT_EQ(0, listen(bind_fd, backlog));
> + EXPECT_EQ(0, listen_variant(bind_fd, backlog));
>
> /* Connects on the binded port 1024. */
> ret = connect_variant(connect_fd, &self->srv0);
> --
> 2.34.1
>
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