On 19/05/2022 14:10, Konstantin Meskhidze wrote:
5/17/2022 12:11 AM, Mickaël Salaün пишет:
On 16/05/2022 17:20, Konstantin Meskhidze wrote:
Adds selftests for bind socket action.
The first is with no landlock restrictions:
- bind_no_restrictions_ip4;
- bind_no_restrictions_ip6;
The second ones is with mixed landlock rules:
- bind_with_restrictions_ip4;
- bind_with_restrictions_ip6;
Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@xxxxxxxxxx>
---
Changes since v3:
* Split commit.
* Add helper create_socket.
* Add FIXTURE_SETUP.
Changes since v4:
* Adds port[MAX_SOCKET_NUM], struct sockaddr_in addr4
and struct sockaddr_in addr6 in FIXTURE.
* Refactoring FIXTURE_SETUP:
- initializing self->port, self->addr4 and self->addr6.
- adding network namespace.
* Refactoring code with self->port, self->addr4 and
self->addr6 variables.
* Adds selftests for IP6 family:
- bind_no_restrictions_ip6.
- bind_with_restrictions_ip6.
* Refactoring selftests/landlock/config
* Moves enforce_ruleset() into common.h
---
tools/testing/selftests/landlock/common.h | 9 +
tools/testing/selftests/landlock/config | 5 +-
tools/testing/selftests/landlock/fs_test.c | 10 -
tools/testing/selftests/landlock/net_test.c | 237 ++++++++++++++++++++
4 files changed, 250 insertions(+), 11 deletions(-)
create mode 100644 tools/testing/selftests/landlock/net_test.c
diff --git a/tools/testing/selftests/landlock/common.h
b/tools/testing/selftests/landlock/common.h
index 7ba18eb23783..c5381e641dfd 100644
--- a/tools/testing/selftests/landlock/common.h
+++ b/tools/testing/selftests/landlock/common.h
@@ -102,6 +102,15 @@ static inline int landlock_restrict_self(const
int ruleset_fd,
}
#endif
+static void enforce_ruleset(struct __test_metadata *const _metadata,
+ const int ruleset_fd)
+{
+ ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+ ASSERT_EQ(0, landlock_restrict_self(ruleset_fd, 0)) {
+ TH_LOG("Failed to enforce ruleset: %s", strerror(errno));
+ }
+}
+
Please create a commit which moves all the needed code for all network
tests. I think there is only this helper though.
Ok. I will create one additional commit for moving this helper.
But after I have moved the helper to common.h, I got warnings while
compiling seltests where I don't use the one (base_test and ptrace_test)
Move it after clear_cap() and use the same attributes.
[...]
>>> diff --git a/tools/testing/selftests/landlock/config
>>> b/tools/testing/selftests/landlock/config
>>> index 0f0a65287bac..b56f3274d3f5 100644
>>> --- a/tools/testing/selftests/landlock/config
>>> +++ b/tools/testing/selftests/landlock/config
>>> @@ -1,7 +1,10 @@
>>> +CONFIG_INET=y
>>> +CONFIG_IPV6=y
>>> +CONFIG_NET=y
>>> CONFIG_OVERLAY_FS=y
>>> CONFIG_SECURITY_LANDLOCK=y
>>> CONFIG_SECURITY_PATH=y
>>> CONFIG_SECURITY=y
>>> CONFIG_SHMEM=y
>>> CONFIG_TMPFS_XATTR=y
>>> -CONFIG_TMPFS=y
>>> +CONFIG_TMPFS=y
>>> \ No newline at end of file
You also need to add CONFIG_NET_NS.
[...]
+ self->port[i] = SOCK_PORT_START + SOCK_PORT_ADD*i;
+ self->addr4[i].sin_family = AF_INET;
+ self->addr4[i].sin_port = htons(self->port[i]);
+ self->addr4[i].sin_addr.s_addr = htonl(INADDR_ANY);
Could you use the local addr (127.0.0.1) instead?
Why cant I use INADDR_ANY here?
You can, but it is cleaner to bind to a specified address (i.e. you
control where a connection come from), and I guess this variable/address
could be used to establish connections as well.
+ memset(&(self->addr4[i].sin_zero), '\0', 8);
+ }
+
+ /* Creates IP6 socket addresses */
+ for (i = 0; i < MAX_SOCKET_NUM; i++) {
+ self->port[i] = SOCK_PORT_START + SOCK_PORT_ADD*i;
+ self->addr6[i].sin6_family = AF_INET6;
+ self->addr6[i].sin6_port = htons(self->port[i]);
+ self->addr6[i].sin6_addr = in6addr_any;
ditto
Why cant I use in6addr_any here?
Same as for IPV4.
+ }
+
+ set_cap(_metadata, CAP_SYS_ADMIN);
+ ASSERT_EQ(0, unshare(CLONE_NEWNET));
+ ASSERT_EQ(0, system("ip link set dev lo up"));
If this is really required, could you avoid calling system() but set
up the network in C? You can strace it to see what is going on
underneath.
I did check. It's a lot of code to be run under the hood (more than
one line) and it will just will complicate the test so I suggest to
leave just ONE line of code here.
OK
+ clear_cap(_metadata, CAP_SYS_ADMIN);
+}
+
+FIXTURE_TEARDOWN(socket_test)
+{ }
+
+TEST_F_FORK(socket_test, bind_no_restrictions_ip4) {
+
+ int sockfd;
+
+ sockfd = create_socket(_metadata, false, false);
+ ASSERT_LE(0, sockfd);
+
+ /* Binds a socket to port[0] */
This comment is not very useful in this context considering the below
line. It will be even more clear with the bind_variant() call.
Ok. I will fix it.
+ ASSERT_EQ(0, bind(sockfd, (struct sockaddr *)&self->addr4[0],
sizeof(self->addr4[0])));
+
+ ASSERT_EQ(0, close(sockfd));
+}
+
+TEST_F_FORK(socket_test, bind_no_restrictions_ip6) {
+
+ int sockfd;
+
+ sockfd = create_socket(_metadata, true, false);
+ ASSERT_LE(0, sockfd);
+
+ /* Binds a socket to port[0] */
+ ASSERT_EQ(0, bind(sockfd, (struct sockaddr *)&self->addr6[0],
sizeof(self->addr6[0])));
+
+ ASSERT_EQ(0, close(sockfd));
+}
+
+TEST_F_FORK(socket_test, bind_with_restrictions_ip4) {
+
+ int sockfd;
+
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ };
+ struct landlock_net_service_attr net_service_1 = {
+ .allowed_access = LANDLOCK_ACCESS_NET_BIND_TCP |
+ LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .port = self->port[0],
+ };
+ struct landlock_net_service_attr net_service_2 = {
+ .allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP,
+ .port = self->port[1],
+ };
+ struct landlock_net_service_attr net_service_3 = {
+ .allowed_access = 0,
+ .port = self->port[2],
+ };
+
+ const int ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+ sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Allows connect and bind operations to the port[0] socket. */
This comment is useful though because the below call is more complex.
So I can leave it as it's, cant I?
Yes, keep it, I'd just like a fair amount of useful comments. ;)
