src/test/test-bpf.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <linux/libbpf.h>
   4 #include <string.h>
   5 #include <unistd.h>
   6
   7 #include "bpf-firewall.h"
   8 #include "bpf-program.h"
   9 #include "load-fragment.h"
  10 #include "manager.h"
  11 #include "rm-rf.h"
  12 #include "service.h"
  13 #include "test-helper.h"
  14 #include "tests.h"
  15 #include "unit.h"
  16
  17 int main(int argc, char *argv[]) {
  18         struct bpf_insn exit_insn[] = {
  19                 BPF_MOV64_IMM(BPF_REG_0, 1),
  20                 BPF_EXIT_INSN()
  21         };
  22
  23         _cleanup_(rm_rf_physical_and_freep) char *runtime_dir = NULL;
  24         CGroupContext *cc = NULL;
  25         _cleanup_(bpf_program_unrefp) BPFProgram *p = NULL;
  26         _cleanup_(manager_freep) Manager *m = NULL;
  27         Unit *u;
  28         char log_buf[65535];
  29         int r;
  30
  31         test_setup_logging(LOG_DEBUG);
  32
  33         r = enter_cgroup_subroot();
  34         if (r == -ENOMEDIUM)
  35                 return log_tests_skipped("cgroupfs not available");
  36
  37         assert_se(set_unit_path(get_testdata_dir()) >= 0);
  38         assert_se(runtime_dir = setup_fake_runtime_dir());
  39
  40         r = bpf_program_new(BPF_PROG_TYPE_CGROUP_SKB, &p);
  41         assert(r == 0);
  42
  43         r = bpf_program_add_instructions(p, exit_insn, ELEMENTSOF(exit_insn));
  44         assert(r == 0);
  45
  46         if (getuid() != 0)
  47                 return log_tests_skipped("not running as root");
  48
  49         r = bpf_firewall_supported();
  50         if (r == BPF_FIREWALL_UNSUPPORTED)
  51                 return log_tests_skipped("BPF firewalling not supported");
  52         assert_se(r > 0);
  53
  54         if (r == BPF_FIREWALL_SUPPORTED_WITH_MULTI)
  55                 log_notice("BPF firewalling with BPF_F_ALLOW_MULTI supported. Yay!");
  56         else
  57                 log_notice("BPF firewalling (though without BPF_F_ALLOW_MULTI) supported. Good.");
  58
  59         r = bpf_program_load_kernel(p, log_buf, ELEMENTSOF(log_buf));
  60         assert(r >= 0);
  61
  62         p = bpf_program_unref(p);
  63
  64         /* The simple tests suceeded. Now let's try full unit-based use-case. */
  65
  66         assert_se(manager_new(UNIT_FILE_USER, MANAGER_TEST_RUN_BASIC, &m) >= 0);
  67         assert_se(manager_startup(m, NULL, NULL) >= 0);
  68
  69         assert_se(u = unit_new(m, sizeof(Service)));
  70         assert_se(unit_add_name(u, "foo.service") == 0);
  71         assert_se(cc = unit_get_cgroup_context(u));
  72         u->perpetual = true;
  73
  74         cc->ip_accounting = true;
  75
  76         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);
  77         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);
  78         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);
  79         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);
  80         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);
  81         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);
  82
  83         assert(cc->ip_address_allow);
  84         assert(cc->ip_address_allow->items_next);
  85         assert(!cc->ip_address_allow->items_next->items_next);
  86
  87         /* The deny list is defined redundantly, let's ensure it got properly reduced */
  88         assert(cc->ip_address_deny);
  89         assert(cc->ip_address_deny->items_next);
  90         assert(!cc->ip_address_deny->items_next->items_next);
  91
  92         assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "/bin/ping -c 1 127.0.0.2 -W 5", SERVICE(u)->exec_command, u) == 0);
  93         assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "/bin/ping -c 1 127.0.0.3 -W 5", SERVICE(u)->exec_command, u) == 0);
  94
  95         assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]);
  96         assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next);
  97         assert_se(!SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->command_next);
  98
  99         SERVICE(u)->type = SERVICE_ONESHOT;
 100         u->load_state = UNIT_LOADED;
 101
 102         unit_dump(u, stdout, NULL);
 103
 104         r = bpf_firewall_compile(u);
 105         if (IN_SET(r, -ENOTTY, -ENOSYS, -EPERM))
 106                 return log_tests_skipped("Kernel doesn't support the necessary bpf bits (masked out via seccomp?)");
 107         assert_se(r >= 0);
 108
 109         assert(u->ip_bpf_ingress);
 110         assert(u->ip_bpf_egress);
 111
 112         r = bpf_program_load_kernel(u->ip_bpf_ingress, log_buf, ELEMENTSOF(log_buf));
 113
 114         log_notice("log:");
 115         log_notice("-------");
 116         log_notice("%s", log_buf);
 117         log_notice("-------");
 118
 119         assert(r >= 0);
 120
 121         r = bpf_program_load_kernel(u->ip_bpf_egress, log_buf, ELEMENTSOF(log_buf));
 122
 123         log_notice("log:");
 124         log_notice("-------");
 125         log_notice("%s", log_buf);
 126         log_notice("-------");
 127
 128         assert(r >= 0);
 129
 130         assert_se(unit_start(u) >= 0);
 131
 132         while (!IN_SET(SERVICE(u)->state, SERVICE_DEAD, SERVICE_FAILED))
 133                 assert_se(sd_event_run(m->event, UINT64_MAX) >= 0);
 134
 135         assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.code == CLD_EXITED &&
 136                   SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.status == EXIT_SUCCESS);
 137
 138         assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->exec_status.code != CLD_EXITED ||
 139                   SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->exec_status.status != EXIT_SUCCESS);
 140
 141         return 0;
 142 }