[PATCH v4 4/7] selftests/landlock: Add UDP bind/connect tests

Matthieu Buffet
2026-05-02T12:44:37Z

Make basic changes to the existing bind() and connect() test suite to
cover UDP restriction.

Signed-off-by: Matthieu Buffet <matthieu@buffet.re>
---
tools/testing/selftests/landlock/net_test.c | 488 ++++++++++++++++----
1 file changed, 401 insertions(+), 87 deletions(-)

diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
index 016c7277e370..568a6ed7139c 100644
--- a/tools/testing/selftests/landlock/net_test.c
+++ b/tools/testing/selftests/landlock/net_test.c
@@ -35,6 +35,7 @@ enum sandbox_type {
NO_SANDBOX,
/* This may be used to test rules that allow *and* deny accesses. */
TCP_SANDBOX,
+ UDP_SANDBOX,
};

static int set_service(struct service_fixture *const srv,
@@ -93,23 +94,53 @@ static bool prot_is_tcp(const struct protocol_variant *const prot)
(prot->protocol == IPPROTO_TCP || prot->protocol == IPPROTO_IP);
}

+static bool prot_is_udp(const struct protocol_variant *const prot)
+{
+ return (prot->domain == AF_INET || prot->domain == AF_INET6) &&
+ prot->type == SOCK_DGRAM &&
+ (prot->protocol == IPPROTO_UDP || prot->protocol == IPPROTO_IP);
+}
+
static bool is_restricted(const struct protocol_variant *const prot,
const enum sandbox_type sandbox)
{
if (sandbox == TCP_SANDBOX)
return prot_is_tcp(prot);
+ else if (sandbox == UDP_SANDBOX)
+ return prot_is_udp(prot);
return false;
}

static int socket_variant(const struct service_fixture *const srv)
{
+ /* Arbitrary value just to not block other tests indefinitely. */
+ const struct timeval timeout = {
+ .tv_sec = 0,
+ .tv_usec = 100000,
+ };
+ int sockfd;
int ret;

- ret = socket(srv->protocol.domain, srv->protocol.type | SOCK_CLOEXEC,
- srv->protocol.protocol);
- if (ret < 0)
+ sockfd = socket(srv->protocol.domain, srv->protocol.type | SOCK_CLOEXEC,
+ srv->protocol.protocol);
+ if (sockfd < 0)
return -errno;
- return ret;
+
+ ret = setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, &timeout,
+ sizeof(timeout));
+ if (ret != 0) {
+ ret = -errno;
+ close(sockfd);
+ return ret;
+ }
+ ret = setsockopt(sockfd, SOL_SOCKET, SO_SNDTIMEO, &timeout,
+ sizeof(timeout));
+ if (ret != 0) {
+ ret = -errno;
+ close(sockfd);
+ return ret;
+ }
+ return sockfd;
}

#ifndef SIN6_LEN_RFC2133
@@ -271,10 +302,9 @@ FIXTURE_VARIANT(protocol)

FIXTURE_SETUP(protocol)
{
- const struct protocol_variant prot_unspec = {
- .domain = AF_UNSPEC,
- .type = SOCK_STREAM,
- };
+ struct protocol_variant prot_unspec = variant->prot;
+
+ prot_unspec.domain = AF_UNSPEC;

disable_caps(_metadata);

@@ -510,6 +540,92 @@ FIXTURE_VARIANT_ADD(protocol, tcp_sandbox_with_unix_datagram) {
},
};

+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_ipv4_udp1) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET,
+ .type = SOCK_DGRAM,
+ .protocol = IPPROTO_UDP,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_ipv4_udp2) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET,
+ .type = SOCK_DGRAM,
+ /* IPPROTO_IP == 0 */
+ .protocol = IPPROTO_IP,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_ipv6_udp1) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET6,
+ .type = SOCK_DGRAM,
+ .protocol = IPPROTO_UDP,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_ipv6_udp2) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET6,
+ .type = SOCK_DGRAM,
+ /* IPPROTO_IP == 0 */
+ .protocol = IPPROTO_IP,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_ipv4_tcp) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET,
+ .type = SOCK_STREAM,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_ipv6_tcp) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET6,
+ .type = SOCK_STREAM,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_unix_stream) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_UNIX,
+ .type = SOCK_STREAM,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(protocol, udp_sandbox_with_unix_datagram) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_UNIX,
+ .type = SOCK_DGRAM,
+ },
+};
+
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)
@@ -602,7 +718,7 @@ 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 && srv->protocol.type == SOCK_STREAM) {
/* No listening server. */
EXPECT_EQ(-ECONNREFUSED, ret);
} else {
@@ -641,18 +757,25 @@ static void test_bind_and_connect(struct __test_metadata *const _metadata,

TEST_F(protocol, bind)
{
- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
+ const __u64 bind_access =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_BIND_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP);
+ const __u64 conn_access =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .handled_access_net = bind_access | conn_access,
};
- 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 bind_connect_p0 = {
+ .allowed_access = bind_access | conn_access,
.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 connect_p1 = {
+ .allowed_access = conn_access,
.port = self->srv1.port,
};
int ruleset_fd;
@@ -664,12 +787,26 @@ TEST_F(protocol, bind)
/* Allows connect and bind for the first port. */
ASSERT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_bind_connect_p0, 0));
+ &bind_connect_p0, 0));

/* Allows connect and denies bind for the second port. */
ASSERT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_connect_p1, 0));
+ &connect_p1, 0));
+
+ /*
+ * For UDP sockets, allows binding to ephemeral ports
+ * (required to connect or send a first datagram)
+ */
+ if (variant->sandbox == UDP_SANDBOX) {
+ const struct landlock_net_port_attr bind_ephemeral = {
+ .allowed_access = bind_access,
+ .port = 0,
+ };
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd,
+ LANDLOCK_RULE_NET_PORT,
+ &bind_ephemeral, 0));
+ }

enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));
@@ -691,18 +828,25 @@ TEST_F(protocol, bind)

TEST_F(protocol, connect)
{
- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
+ const __u64 bind_access =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_BIND_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP);
+ const __u64 conn_access =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .handled_access_net = bind_access | conn_access,
};
- 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 bind_connect_p0 = {
+ .allowed_access = bind_access | conn_access,
.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 bind_p1 = {
+ .allowed_access = bind_access,
.port = self->srv1.port,
};
int ruleset_fd;
@@ -714,12 +858,26 @@ TEST_F(protocol, connect)
/* Allows connect and bind for the first port. */
ASSERT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_bind_connect_p0, 0));
+ &bind_connect_p0, 0));

/* Allows bind and denies connect for the second port. */
ASSERT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_bind_p1, 0));
+ &bind_p1, 0));
+
+ /*
+ * For UDP sockets, allows binding to ephemeral ports
+ * (required to connect or send a first datagram)
+ */
+ if (variant->sandbox == UDP_SANDBOX) {
+ const struct landlock_net_port_attr bind_ephemeral = {
+ .allowed_access = bind_access,
+ .port = 0,
+ };
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd,
+ LANDLOCK_RULE_NET_PORT,
+ &bind_ephemeral, 0));
+ }

enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));
@@ -737,16 +895,20 @@ TEST_F(protocol, connect)

TEST_F(protocol, bind_unspec)
{
+ const int bind_access = (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_BIND_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP,
+ .handled_access_net = bind_access,
};
- const struct landlock_net_port_attr tcp_bind = {
- .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP,
+ const struct landlock_net_port_attr rule_bind = {
+ .allowed_access = bind_access,
.port = self->srv0.port,
};
int bind_fd, ret;

- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
const int ruleset_fd = landlock_create_ruleset(
&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
@@ -754,7 +916,7 @@ TEST_F(protocol, bind_unspec)
/* Allows bind. */
ASSERT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_bind, 0));
+ &rule_bind, 0));
enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));
}
@@ -782,7 +944,8 @@ TEST_F(protocol, bind_unspec)
}
EXPECT_EQ(0, close(bind_fd));

- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
const int ruleset_fd = landlock_create_ruleset(
&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
@@ -828,11 +991,15 @@ TEST_F(protocol, bind_unspec)

TEST_F(protocol, connect_unspec)
{
+ const __u64 connect_right =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .handled_access_net = connect_right,
};
- const struct landlock_net_port_attr tcp_connect = {
- .allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ const struct landlock_net_port_attr rule_connect = {
+ .allowed_access = connect_right,
.port = self->srv0.port,
};
int bind_fd, client_fd, status;
@@ -865,7 +1032,8 @@ TEST_F(protocol, connect_unspec)
EXPECT_EQ(0, ret);
}

- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
const int ruleset_fd = landlock_create_ruleset(
&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
@@ -873,7 +1041,7 @@ TEST_F(protocol, connect_unspec)
/* Allows connect. */
ASSERT_EQ(0, landlock_add_rule(ruleset_fd,
LANDLOCK_RULE_NET_PORT,
- &tcp_connect, 0));
+ &rule_connect, 0));
enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));
}
@@ -896,7 +1064,8 @@ TEST_F(protocol, connect_unspec)
EXPECT_EQ(0, ret);
}

- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
const int ruleset_fd = landlock_create_ruleset(
&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
@@ -975,6 +1144,13 @@ FIXTURE_VARIANT_ADD(ipv4, tcp_sandbox_with_tcp) {
.type = SOCK_STREAM,
};

+/* clang-format off */
+FIXTURE_VARIANT_ADD(ipv4, udp_sandbox_with_tcp) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .type = SOCK_STREAM,
+};
+
/* clang-format off */
FIXTURE_VARIANT_ADD(ipv4, no_sandbox_with_udp) {
/* clang-format on */
@@ -989,6 +1165,13 @@ FIXTURE_VARIANT_ADD(ipv4, tcp_sandbox_with_udp) {
.type = SOCK_DGRAM,
};

+/* clang-format off */
+FIXTURE_VARIANT_ADD(ipv4, udp_sandbox_with_udp) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .type = SOCK_DGRAM,
+};
+
FIXTURE_SETUP(ipv4)
{
const struct protocol_variant prot = {
@@ -1012,14 +1195,19 @@ TEST_F(ipv4, from_unix_to_inet)
{
int unix_stream_fd, unix_dgram_fd;

- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
+ const int access_rights =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP |
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .handled_access_net = access_rights,
};
const struct landlock_net_port_attr tcp_bind_connect_p0 = {
- .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .allowed_access = access_rights,
.port = self->srv0.port,
};
int ruleset_fd;
@@ -1680,6 +1868,7 @@ TEST_F(ipv4_tcp, with_fs)
FIXTURE(port_specific)
{
struct service_fixture srv0;
+ struct service_fixture cli1;
};

FIXTURE_VARIANT(port_specific)
@@ -1699,7 +1888,7 @@ FIXTURE_VARIANT_ADD(port_specific, no_sandbox_with_ipv4) {
};

/* clang-format off */
-FIXTURE_VARIANT_ADD(port_specific, sandbox_with_ipv4) {
+FIXTURE_VARIANT_ADD(port_specific, tcp_sandbox_with_ipv4) {
/* clang-format on */
.sandbox = TCP_SANDBOX,
.prot = {
@@ -1708,6 +1897,16 @@ FIXTURE_VARIANT_ADD(port_specific, sandbox_with_ipv4) {
},
};

+/* clang-format off */
+FIXTURE_VARIANT_ADD(port_specific, udp_sandbox_with_ipv4) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET,
+ .type = SOCK_DGRAM,
+ },
+};
+
/* clang-format off */
FIXTURE_VARIANT_ADD(port_specific, no_sandbox_with_ipv6) {
/* clang-format on */
@@ -1719,7 +1918,7 @@ FIXTURE_VARIANT_ADD(port_specific, no_sandbox_with_ipv6) {
};

/* clang-format off */
-FIXTURE_VARIANT_ADD(port_specific, sandbox_with_ipv6) {
+FIXTURE_VARIANT_ADD(port_specific, tcp_sandbox_with_ipv6) {
/* clang-format on */
.sandbox = TCP_SANDBOX,
.prot = {
@@ -1728,11 +1927,22 @@ FIXTURE_VARIANT_ADD(port_specific, sandbox_with_ipv6) {
},
};

+/* clang-format off */
+FIXTURE_VARIANT_ADD(port_specific, udp_sandbox_with_ipv6) {
+ /* clang-format on */
+ .sandbox = UDP_SANDBOX,
+ .prot = {
+ .domain = AF_INET6,
+ .type = SOCK_DGRAM,
+ },
+};
+
FIXTURE_SETUP(port_specific)
{
disable_caps(_metadata);

ASSERT_EQ(0, set_service(&self->srv0, variant->prot, 0));
+ ASSERT_EQ(0, set_service(&self->cli1, variant->prot, 1));

setup_loopback(_metadata);
};
@@ -1747,14 +1957,19 @@ TEST_F(port_specific, bind_connect_zero)
uint16_t port;

/* Adds a rule layer with bind and connect actions. */
- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
+ const int access_rights =
+ (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP |
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP
+ .handled_access_net = access_rights,
};
- const struct landlock_net_port_attr tcp_bind_connect_zero = {
- .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ const struct landlock_net_port_attr bind_connect_zero = {
+ .allowed_access = access_rights,
.port = 0,
};
int ruleset_fd;
@@ -1766,7 +1981,7 @@ TEST_F(port_specific, bind_connect_zero)
/* Checks zero port value on bind and connect actions. */
EXPECT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_bind_connect_zero, 0));
+ &bind_connect_zero, 0));

enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));
@@ -1787,11 +2002,16 @@ 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));
+ if (variant->prot.type == SOCK_STREAM)
+ EXPECT_EQ(0, listen(bind_fd, backlog));

/* Connects on port 0. */
ret = connect_variant(connect_fd, &self->srv0);
- EXPECT_EQ(-ECONNREFUSED, ret);
+ if (variant->prot.type == SOCK_STREAM) {
+ EXPECT_EQ(-ECONNREFUSED, ret);
+ } else {
+ EXPECT_EQ(0, ret);
+ }

/* Sets binded port for both protocol families. */
port = get_binded_port(bind_fd, &variant->prot);
@@ -1815,23 +2035,35 @@ TEST_F(port_specific, bind_connect_1023)
int bind_fd, connect_fd, ret;

/* Adds a rule layer with bind and connect actions. */
- if (variant->sandbox == TCP_SANDBOX) {
+ if (variant->sandbox == TCP_SANDBOX ||
+ variant->sandbox == UDP_SANDBOX) {
+ const int bind_right = (variant->sandbox == TCP_SANDBOX ?
+ LANDLOCK_ACCESS_NET_BIND_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP);
+ const int access_rights =
+ (variant->sandbox == TCP_SANDBOX ?
+ (LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP) :
+ (LANDLOCK_ACCESS_NET_BIND_UDP |
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP));
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP
+ .handled_access_net = access_rights,
};
/* 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 bind_connect_low_range = {
+ .allowed_access = access_rights,
.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 bind_connect = {
+ .allowed_access = access_rights,
.port = 1024,
};
+ /* A rule with cli1's port, to use as source port. */
+ const struct landlock_net_port_attr srcport = {
+ .allowed_access = bind_right,
+ .port = self->cli1.port,
+ };
int ruleset_fd;

ruleset_fd = landlock_create_ruleset(&ruleset_attr,
@@ -1840,10 +2072,15 @@ 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));
+ &bind_connect_low_range, 0));
ASSERT_EQ(0,
landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
- &tcp_bind_connect, 0));
+ &bind_connect, 0));
+ if (variant->sandbox == UDP_SANDBOX) {
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd,
+ LANDLOCK_RULE_NET_PORT,
+ &srcport, 0));
+ }

enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));
@@ -1867,8 +2104,19 @@ 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));
+ if (variant->prot.type == SOCK_STREAM)
+ EXPECT_EQ(0, listen(bind_fd, backlog));

+ connect_fd = socket_variant(&self->srv0);
+ ASSERT_LE(0, connect_fd);
+ if (variant->prot.type == SOCK_DGRAM) {
+ /*
+ * We are about to connect(), but bind() is restricted, so for
+ * UDP sockets we need to use cli1's port as source port (the
+ * only one we are allowed to use).
+ */
+ EXPECT_EQ(0, bind_variant(connect_fd, &self->cli1));
+ }
/* Connects on the binded port 1023. */
ret = connect_variant(connect_fd, &self->srv0);
EXPECT_EQ(0, ret);
@@ -1887,7 +2135,10 @@ 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));
+ if (variant->prot.type == SOCK_STREAM)
+ EXPECT_EQ(0, listen(bind_fd, backlog));
+ if (variant->prot.type == SOCK_DGRAM)
+ EXPECT_EQ(0, bind_variant(connect_fd, &self->cli1));

/* Connects on the binded port 1024. */
ret = connect_variant(connect_fd, &self->srv0);
@@ -1897,23 +2148,30 @@ TEST_F(port_specific, bind_connect_1023)
EXPECT_EQ(0, close(bind_fd));
}

-static int matches_log_tcp(const int audit_fd, const char *const blockers,
- const char *const dir_addr, const char *const addr,
- const char *const dir_port)
+static int matches_auditlog(const int audit_fd, const char *const blockers,
+ const char *const dir_addr, const char *const addr,
+ const char *const dir_port)
{
- static const char log_template[] = REGEX_LANDLOCK_PREFIX
+ static const char log_with_addrport_tmpl[] = REGEX_LANDLOCK_PREFIX
" blockers=%s %s=%s %s=1024$";
+ static const char log_without_addrport_tmpl[] = REGEX_LANDLOCK_PREFIX
+ " blockers=%s";
/*
* Max strlen(blockers): 16
* Max strlen(dir_addr): 5
* Max strlen(addr): 12
* Max strlen(dir_port): 4
*/
- char log_match[sizeof(log_template) + 37];
+ char log_match[sizeof(log_with_addrport_tmpl) + 37];
int log_match_len;

- log_match_len = snprintf(log_match, sizeof(log_match), log_template,
- blockers, dir_addr, addr, dir_port);
+ if (addr == NULL)
+ log_match_len = snprintf(log_match, sizeof(log_match),
+ log_without_addrport_tmpl, blockers);
+ else
+ log_match_len = snprintf(log_match, sizeof(log_match),
+ log_with_addrport_tmpl, blockers,
+ dir_addr, addr, dir_port);
if (log_match_len > sizeof(log_match))
return -E2BIG;

@@ -1924,6 +2182,7 @@ static int matches_log_tcp(const int audit_fd, const char *const blockers,
FIXTURE(audit)
{
struct service_fixture srv0;
+ struct service_fixture srv1;
struct audit_filter audit_filter;
int audit_fd;
};
@@ -1935,7 +2194,7 @@ FIXTURE_VARIANT(audit)
};

/* clang-format off */
-FIXTURE_VARIANT_ADD(audit, ipv4) {
+FIXTURE_VARIANT_ADD(audit, ipv4_tcp) {
/* clang-format on */
.addr = "127\\.0\\.0\\.1",
.prot = {
@@ -1945,7 +2204,17 @@ FIXTURE_VARIANT_ADD(audit, ipv4) {
};

/* clang-format off */
-FIXTURE_VARIANT_ADD(audit, ipv6) {
+FIXTURE_VARIANT_ADD(audit, ipv4_udp) {
+ /* clang-format on */
+ .addr = "127\\.0\\.0\\.1",
+ .prot = {
+ .domain = AF_INET,
+ .type = SOCK_DGRAM,
+ },
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(audit, ipv6_tcp) {
/* clang-format on */
.addr = "::1",
.prot = {
@@ -1954,9 +2223,21 @@ FIXTURE_VARIANT_ADD(audit, ipv6) {
},
};

+/* clang-format off */
+FIXTURE_VARIANT_ADD(audit, ipv6_udp) {
+ /* clang-format on */
+ .addr = "::1",
+ .prot = {
+ .domain = AF_INET6,
+ .type = SOCK_DGRAM,
+ },
+};
+
FIXTURE_SETUP(audit)
{
ASSERT_EQ(0, set_service(&self->srv0, variant->prot, 0));
+ ASSERT_EQ(0, set_service(&self->srv1, variant->prot, 1));
+
setup_loopback(_metadata);

set_cap(_metadata, CAP_AUDIT_CONTROL);
@@ -1974,9 +2255,17 @@ FIXTURE_TEARDOWN(audit)

TEST_F(audit, bind)
{
+ const char *audit_evt = (variant->prot.type == SOCK_STREAM ?
+ "net\\.bind_tcp" :
+ "net\\.bind_udp");
+ const int access_rights =
+ (variant->prot.type == SOCK_STREAM ?
+ LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP |
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .handled_access_net = access_rights,
};
struct audit_records records;
int ruleset_fd, sock_fd;
@@ -1990,8 +2279,8 @@ TEST_F(audit, bind)
sock_fd = socket_variant(&self->srv0);
ASSERT_LE(0, sock_fd);
EXPECT_EQ(-EACCES, bind_variant(sock_fd, &self->srv0));
- EXPECT_EQ(0, matches_log_tcp(self->audit_fd, "net\\.bind_tcp", "saddr",
- variant->addr, "src"));
+ EXPECT_EQ(0, matches_auditlog(self->audit_fd, audit_evt, "saddr",
+ variant->addr, "src"));

EXPECT_EQ(0, audit_count_records(self->audit_fd, &records));
EXPECT_EQ(0, records.access);
@@ -2002,9 +2291,22 @@ TEST_F(audit, bind)

TEST_F(audit, connect)
{
+ const char *audit_evt = (variant->prot.type == SOCK_STREAM ?
+ "net\\.connect_tcp" :
+ "net\\.connect_send_udp");
+ const int bind_right = (variant->prot.type == SOCK_STREAM ?
+ LANDLOCK_ACCESS_NET_BIND_TCP :
+ LANDLOCK_ACCESS_NET_BIND_UDP);
+ const int conn_right = (variant->prot.type == SOCK_STREAM ?
+ LANDLOCK_ACCESS_NET_CONNECT_TCP :
+ LANDLOCK_ACCESS_NET_CONNECT_SEND_UDP);
+ const int access_rights = bind_right | conn_right;
const struct landlock_ruleset_attr ruleset_attr = {
- .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
- LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .handled_access_net = access_rights,
+ };
+ const struct landlock_net_port_attr rule_connect_p1 = {
+ .allowed_access = conn_right,
+ .port = self->srv1.port,
};
struct audit_records records;
int ruleset_fd, sock_fd;
@@ -2012,19 +2314,31 @@ TEST_F(audit, connect)
ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
+ &rule_connect_p1, 0));
enforce_ruleset(_metadata, ruleset_fd);
EXPECT_EQ(0, close(ruleset_fd));

sock_fd = socket_variant(&self->srv0);
ASSERT_LE(0, sock_fd);
EXPECT_EQ(-EACCES, connect_variant(sock_fd, &self->srv0));
- EXPECT_EQ(0, matches_log_tcp(self->audit_fd, "net\\.connect_tcp",
- "daddr", variant->addr, "dest"));
+ EXPECT_EQ(0, matches_auditlog(self->audit_fd, audit_evt, "daddr",
+ variant->addr, "dest"));

EXPECT_EQ(0, audit_count_records(self->audit_fd, &records));
EXPECT_EQ(0, records.access);
EXPECT_EQ(1, records.domain);

+ if (variant->prot.type == SOCK_DGRAM) {
+ /* Check that autobind generates a denied bind event. */
+ EXPECT_EQ(-EACCES, connect_variant(sock_fd, &self->srv1));
+
+ EXPECT_EQ(0, matches_auditlog(self->audit_fd, "net\\.bind_udp",
+ NULL, NULL, NULL));
+ EXPECT_EQ(0, records.access);
+ EXPECT_EQ(1, records.domain);
+ }
+
EXPECT_EQ(0, close(sock_fd));
}

--
2.39.5