Merge pull request #4536 from poettering/seccomp-namespaces

core: add new RestrictNamespaces= unit file setting

Merging, not rebasing, because this touches many files and there were tree-wide cleanups in the mean time.
This commit is contained in:
Zbigniew Jędrzejewski-Szmek
2016-11-08 19:54:21 -05:00
committed by GitHub
15 changed files with 534 additions and 23 deletions
+94
View File
@@ -20,10 +20,15 @@
#include <stdlib.h>
#include <sys/eventfd.h>
#include <unistd.h>
#include <sched.h>
#include "alloc-util.h"
#include "fd-util.h"
#include "macro.h"
#include "missing.h"
#include "nsflags.h"
#include "process-util.h"
#include "raw-clone.h"
#include "seccomp-util.h"
#include "string-util.h"
#include "util.h"
@@ -125,12 +130,101 @@ static void test_filter_sets(void) {
}
}
static void test_restrict_namespace(void) {
_cleanup_free_ char *s = NULL;
pid_t pid;
unsigned long ul;
assert_se(namespace_flag_to_string(0) == NULL);
assert_se(streq(namespace_flag_to_string(CLONE_NEWNS), "mnt"));
assert_se(namespace_flag_to_string(CLONE_NEWNS|CLONE_NEWIPC) == NULL);
assert_se(streq(namespace_flag_to_string(CLONE_NEWCGROUP), "cgroup"));
assert_se(namespace_flag_from_string("mnt") == CLONE_NEWNS);
assert_se(namespace_flag_from_string(NULL) == 0);
assert_se(namespace_flag_from_string("") == 0);
assert_se(namespace_flag_from_string("uts") == CLONE_NEWUTS);
assert_se(namespace_flag_from_string(namespace_flag_to_string(CLONE_NEWUTS)) == CLONE_NEWUTS);
assert_se(streq(namespace_flag_to_string(namespace_flag_from_string("ipc")), "ipc"));
assert_se(namespace_flag_from_string_many(NULL, &ul) == 0 && ul == 0);
assert_se(namespace_flag_from_string_many("", &ul) == 0 && ul == 0);
assert_se(namespace_flag_from_string_many("mnt uts ipc", &ul) == 0 && ul == (CLONE_NEWNS|CLONE_NEWUTS|CLONE_NEWIPC));
assert_se(namespace_flag_to_string_many(NAMESPACE_FLAGS_ALL, &s) == 0);
assert_se(streq(s, "cgroup ipc net mnt pid user uts"));
assert_se(namespace_flag_from_string_many(s, &ul) == 0 && ul == NAMESPACE_FLAGS_ALL);
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
assert_se(seccomp_restrict_namespaces(CLONE_NEWNS|CLONE_NEWNET) >= 0);
assert_se(unshare(CLONE_NEWNS) == 0);
assert_se(unshare(CLONE_NEWNET) == 0);
assert_se(unshare(CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
assert_se(unshare(CLONE_NEWIPC) == -1);
assert_se(errno == EPERM);
assert_se(unshare(CLONE_NEWNET|CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
/* We use fd 0 (stdin) here, which of course will fail with EINVAL on setns(). Except of course our
* seccomp filter worked, and hits first and makes it return EPERM */
assert_se(setns(0, CLONE_NEWNS) == -1);
assert_se(errno == EINVAL);
assert_se(setns(0, CLONE_NEWNET) == -1);
assert_se(errno == EINVAL);
assert_se(setns(0, CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
assert_se(setns(0, CLONE_NEWIPC) == -1);
assert_se(errno == EPERM);
assert_se(setns(0, CLONE_NEWNET|CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
assert_se(setns(0, 0) == -1);
assert_se(errno == EPERM);
pid = raw_clone(CLONE_NEWNS);
assert_se(pid >= 0);
if (pid == 0)
_exit(EXIT_SUCCESS);
pid = raw_clone(CLONE_NEWNET);
assert_se(pid >= 0);
if (pid == 0)
_exit(EXIT_SUCCESS);
pid = raw_clone(CLONE_NEWUTS);
assert_se(pid < 0);
assert_se(errno == EPERM);
pid = raw_clone(CLONE_NEWIPC);
assert_se(pid < 0);
assert_se(errno == EPERM);
pid = raw_clone(CLONE_NEWNET|CLONE_NEWUTS);
assert_se(pid < 0);
assert_se(errno == EPERM);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_warn("nsseccomp", pid, true) == EXIT_SUCCESS);
}
int main(int argc, char *argv[]) {
log_set_max_level(LOG_DEBUG);
test_seccomp_arch_to_string();
test_architecture_table();
test_syscall_filter_set_find();
test_filter_sets();
test_restrict_namespace();
return 0;
}