Add test for eBPF firewall code

src/test/meson.build

@@ -339,6 +339,17 @@ tests += [
          [libbasic],
          []],
 
+        [['src/test/test-bpf.c',
+          'src/test/test-helper.c'],
+         [libcore,
+          libshared],
+         [libmount,
+          threads,
+          librt,
+          libseccomp,
+          libselinux,
+          libblkid]],
+
         [['src/test/test-hashmap.c',
           'src/test/test-hashmap-plain.c',
           test_hashmap_ordered_c],

src/test/test-bpf.c

@@ -0,0 +1,162 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2016 Daniel Mack
+
+  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/>.
+***/
+
+#include <linux/libbpf.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "bpf-firewall.h"
+#include "bpf-program.h"
+#include "load-fragment.h"
+#include "manager.h"
+#include "rm-rf.h"
+#include "service.h"
+#include "test-helper.h"
+#include "tests.h"
+#include "unit.h"
+
+int main(int argc, char *argv[]) {
+        struct bpf_insn exit_insn[] = {
+                BPF_MOV64_IMM(BPF_REG_0, 1),
+                BPF_EXIT_INSN()
+        };
+
+        _cleanup_(rm_rf_physical_and_freep) char *runtime_dir = NULL;
+        CGroupContext *cc = NULL;
+        _cleanup_(bpf_program_unrefp) BPFProgram *p = NULL;
+        Manager *m = NULL;
+        Unit *u;
+        char log_buf[65535];
+        int r;
+
+        log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
+        log_open();
+
+        enter_cgroup_subroot();
+        assert_se(set_unit_path(get_testdata_dir("")) >= 0);
+        assert_se(runtime_dir = setup_fake_runtime_dir());
+
+        r = bpf_program_new(BPF_PROG_TYPE_CGROUP_SKB, &p);
+        assert(r == 0);
+
+        r = bpf_program_add_instructions(p, exit_insn, ELEMENTSOF(exit_insn));
+        assert(r == 0);
+
+        if (getuid() != 0) {
+                log_notice("Not running as root, skipping kernel related tests.");
+                return EXIT_TEST_SKIP;
+        }
+
+        r = bpf_firewall_supported();
+        if (r == 0) {
+                log_notice("BPF firewalling not supported, skipping");
+                return EXIT_TEST_SKIP;
+        }
+        assert_se(r > 0);
+
+        r = bpf_program_load_kernel(p, log_buf, ELEMENTSOF(log_buf));
+        assert(r >= 0);
+
+        p = bpf_program_unref(p);
+
+        /* The simple tests suceeded. Now let's try full unit-based use-case. */
+
+        assert_se(manager_new(UNIT_FILE_USER, true, &m) >= 0);
+        assert_se(manager_startup(m, NULL, NULL) >= 0);
+
+        assert_se(u = unit_new(m, sizeof(Service)));
+        assert_se(unit_add_name(u, "foo.service") == 0);
+        assert_se(cc = unit_get_cgroup_context(u));
+        u->perpetual = true;
+
+        cc->ip_accounting = true;
+
+        assert_se(config_parse_ip_address_access(u->id, "filename", 1, "Service", 1, "IPAddressAllow", 0, "10.0.1.0/24", &cc->ip_address_allow, NULL) == 0);
+        assert_se(config_parse_ip_address_access(u->id, "filename", 1, "Service", 1, "IPAddressAllow", 0, "127.0.0.2", &cc->ip_address_allow, NULL) == 0);
+        assert_se(config_parse_ip_address_access(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "127.0.0.3", &cc->ip_address_deny, NULL) == 0);
+        assert_se(config_parse_ip_address_access(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "10.0.3.2/24", &cc->ip_address_deny, NULL) == 0);
+        assert_se(config_parse_ip_address_access(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "127.0.0.1/25", &cc->ip_address_deny, NULL) == 0);
+        assert_se(config_parse_ip_address_access(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "127.0.0.4", &cc->ip_address_deny, NULL) == 0);
+
+        assert(cc->ip_address_allow);
+        assert(cc->ip_address_allow->items_next);
+        assert(!cc->ip_address_allow->items_next->items_next);
+
+        /* The deny list is defined redundantly, let's ensure it got properly reduced */
+        assert(cc->ip_address_deny);
+        assert(cc->ip_address_deny->items_next);
+        assert(!cc->ip_address_deny->items_next->items_next);
+
+        assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "/usr/bin/ping -c 1 127.0.0.2 -W 5", SERVICE(u)->exec_command, u) == 0);
+        assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "/usr/bin/ping -c 1 127.0.0.3 -W 5", SERVICE(u)->exec_command, u) == 0);
+
+        assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]);
+        assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next);
+        assert_se(!SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->command_next);
+
+        SERVICE(u)->type = SERVICE_ONESHOT;
+        u->load_state = UNIT_LOADED;
+
+        unit_dump(u, stdout, NULL);
+
+        r = bpf_firewall_compile(u);
+        if (IN_SET(r, -ENOTTY, -ENOSYS, -EPERM )) {
+                /* Kernel doesn't support the necessary bpf bits, or masked out via seccomp? */
+                manager_free(m);
+                return EXIT_TEST_SKIP;
+        }
+        assert_se(r >= 0);
+
+        assert(u->ip_bpf_ingress);
+        assert(u->ip_bpf_egress);
+
+        r = bpf_program_load_kernel(u->ip_bpf_ingress, log_buf, ELEMENTSOF(log_buf));
+
+        log_notice("log:");
+        log_notice("-------");
+        log_notice("%s", log_buf);
+        log_notice("-------");
+
+        assert(r >= 0);
+
+        r = bpf_program_load_kernel(u->ip_bpf_egress, log_buf, ELEMENTSOF(log_buf));
+
+        log_notice("log:");
+        log_notice("-------");
+        log_notice("%s", log_buf);
+        log_notice("-------");
+
+        assert(r >= 0);
+
+        assert(unit_start(u) >= 0);
+
+        while (!IN_SET(SERVICE(u)->state, SERVICE_DEAD, SERVICE_FAILED))
+                assert_se(sd_event_run(m->event, UINT64_MAX) >= 0);
+
+        assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.code == CLD_EXITED &&
+                  SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.status == EXIT_SUCCESS);
+
+        assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->exec_status.code != CLD_EXITED ||
+                  SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->exec_status.status != EXIT_SUCCESS);
+
+        manager_free(m);
+
+        return 0;
+}