-/***
- This file is part of systemd
-
- Copyright 2014 Ronny Chevalier
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
+/* SPDX-License-Identifier: LGPL-2.1+ */
#include <netinet/in.h>
#include <pwd.h>
#include <sys/capability.h>
+#include <sys/prctl.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
+#include "alloc-util.h"
#include "capability-util.h"
#include "fd-util.h"
+#include "fileio.h"
#include "macro.h"
+#include "missing_prctl.h"
+#include "parse-util.h"
+#include "tests.h"
#include "util.h"
static uid_t test_uid = -1;
static gid_t test_gid = -1;
+#if HAS_FEATURE_ADDRESS_SANITIZER
+/* Keep CAP_SYS_PTRACE when running under Address Sanitizer */
+static const uint64_t test_flags = UINT64_C(1) << CAP_SYS_PTRACE;
+#else
/* We keep CAP_DAC_OVERRIDE to avoid errors with gcov when doing test coverage */
-static uint64_t test_flags = 1ULL << CAP_DAC_OVERRIDE;
+static const uint64_t test_flags = UINT64_C(1) << CAP_DAC_OVERRIDE;
+#endif
+
+/* verify cap_last_cap() against /proc/sys/kernel/cap_last_cap */
+static void test_last_cap_file(void) {
+ _cleanup_free_ char *content = NULL;
+ unsigned long val = 0;
+ int r;
+
+ r = read_one_line_file("/proc/sys/kernel/cap_last_cap", &content);
+ assert_se(r >= 0);
+
+ r = safe_atolu(content, &val);
+ assert_se(r >= 0);
+ assert_se(val != 0);
+ assert_se(val == cap_last_cap());
+}
+
+/* verify cap_last_cap() against syscall probing */
+static void test_last_cap_probe(void) {
+ unsigned long p = (unsigned long)CAP_LAST_CAP;
+
+ if (prctl(PR_CAPBSET_READ, p) < 0) {
+ for (p--; p > 0; p --)
+ if (prctl(PR_CAPBSET_READ, p) >= 0)
+ break;
+ } else {
+ for (;; p++)
+ if (prctl(PR_CAPBSET_READ, p+1) < 0)
+ break;
+ }
+
+ assert_se(p != 0);
+ assert_se(p == cap_last_cap());
+}
static void fork_test(void (*test_func)(void)) {
pid_t pid = 0;
assert_se(pid >= 0);
if (pid == 0) {
test_func();
- exit(0);
+ exit(EXIT_SUCCESS);
} else if (pid > 0) {
int status;
cap_free(text);
}
-static int setup_tests(void) {
+static int setup_tests(bool *run_ambient) {
struct passwd *nobody;
+ int r;
+
+ nobody = getpwnam(NOBODY_USER_NAME);
+ if (!nobody)
+ return log_error_errno(errno, "Could not find nobody user: %m");
- nobody = getpwnam("nobody");
- if (!nobody) {
- log_error_errno(errno, "Could not find nobody user: %m");
- return -EXIT_TEST_SKIP;
- }
test_uid = nobody->pw_uid;
test_gid = nobody->pw_gid;
+ *run_ambient = false;
+
+ r = prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_CLEAR_ALL, 0, 0, 0);
+
+ /* There's support for PR_CAP_AMBIENT if the prctl() call
+ * succeeded or error code was something else than EINVAL. The
+ * EINVAL check should be good enough to rule out false
+ * positives. */
+
+ if (r >= 0 || errno != EINVAL)
+ *run_ambient = true;
+
return 0;
}
assert_se(!have_effective_cap(CAP_CHOWN));
}
+static void test_update_inherited_set(void) {
+ cap_t caps;
+ uint64_t set = 0;
+ cap_flag_value_t fv;
+
+ caps = cap_get_proc();
+ assert_se(caps);
+
+ set = (UINT64_C(1) << CAP_CHOWN);
+
+ assert_se(!capability_update_inherited_set(caps, set));
+ assert_se(!cap_get_flag(caps, CAP_CHOWN, CAP_INHERITABLE, &fv));
+ assert(fv == CAP_SET);
+
+ cap_free(caps);
+}
+
+static void test_set_ambient_caps(void) {
+ cap_t caps;
+ uint64_t set = 0;
+ cap_flag_value_t fv;
+
+ assert_se(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, CAP_CHOWN, 0, 0) == 0);
+
+ set = (UINT64_C(1) << CAP_CHOWN);
+
+ assert_se(!capability_ambient_set_apply(set, true));
+
+ caps = cap_get_proc();
+ assert_se(!cap_get_flag(caps, CAP_CHOWN, CAP_INHERITABLE, &fv));
+ assert(fv == CAP_SET);
+ cap_free(caps);
+
+ assert_se(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, CAP_CHOWN, 0, 0) == 1);
+}
+
int main(int argc, char *argv[]) {
- int r;
+ bool run_ambient;
+
+ test_setup_logging(LOG_INFO);
+
+ test_last_cap_file();
+ test_last_cap_probe();
- log_parse_environment();
- log_open();
+ log_info("have ambient caps: %s", yes_no(ambient_capabilities_supported()));
if (getuid() != 0)
- return EXIT_TEST_SKIP;
+ return log_tests_skipped("not running as root");
- r = setup_tests();
- if (r < 0)
- return -r;
+ if (setup_tests(&run_ambient) < 0)
+ return log_tests_skipped("setup failed");
show_capabilities();
test_drop_privileges();
+ test_update_inherited_set();
+
fork_test(test_have_effective_cap);
+ if (run_ambient)
+ fork_test(test_set_ambient_caps);
+
return 0;
}