src/test/test-bpf-foreign-programs.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <fcntl.h>
   4 #include <linux/bpf_insn.h>
   5 #include <string.h>
   6 #include <sys/mman.h>
   7 #include <unistd.h>
   8
   9 #include "bpf-foreign.h"
  10 #include "load-fragment.h"
  11 #include "manager.h"
  12 #include "process-util.h"
  13 #include "rlimit-util.h"
  14 #include "rm-rf.h"
  15 #include "service.h"
  16 #include "tests.h"
  17 #include "unit.h"
  18 #include "virt.h"
  19
  20 struct Test {
  21         const char *option_name;
  22         enum bpf_prog_type prog_type;
  23         enum bpf_attach_type attach_type;
  24         const char *bpffs_path;
  25 };
  26
  27 typedef struct Test Test;
  28
  29 #define BPFFS_PATH(prog_suffix) ("/sys/fs/bpf/test-bpf-foreing-" # prog_suffix)
  30 static const Test single_prog[] = {
  31         {
  32                 .option_name = "BPFProgram",
  33                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
  34                 .attach_type = BPF_CGROUP_INET_INGRESS,
  35                 .bpffs_path = BPFFS_PATH("trivial-skb"),
  36         },
  37 };
  38 static const Test path_split_test[] = {
  39         {
  40                 .option_name = "BPFProgram",
  41                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
  42                 .attach_type = BPF_CGROUP_INET_INGRESS,
  43                 .bpffs_path = BPFFS_PATH("path:split:test"),
  44         },
  45 };
  46
  47 static const Test same_prog_same_hook[] = {
  48         {
  49                 .option_name = "BPFProgram",
  50                 .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
  51                 .attach_type = BPF_CGROUP_INET_SOCK_CREATE,
  52                 .bpffs_path = BPFFS_PATH("trivial-sock"),
  53         },
  54         {
  55                 .option_name = "BPFProgram",
  56                 .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
  57                 .attach_type = BPF_CGROUP_INET_SOCK_CREATE,
  58                 .bpffs_path = BPFFS_PATH("trivial-sock"),
  59         }
  60 };
  61
  62 static const Test multi_prog_same_hook[] = {
  63         {
  64                 .option_name = "BPFProgram",
  65                 .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
  66                 .attach_type = BPF_CGROUP_INET_SOCK_CREATE,
  67                 .bpffs_path = BPFFS_PATH("trivial-sock-0"),
  68         },
  69         {
  70                 .option_name = "BPFProgram",
  71                 .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
  72                 .attach_type = BPF_CGROUP_INET_SOCK_CREATE,
  73                 .bpffs_path = BPFFS_PATH("trivial-sock-1"),
  74         }
  75 };
  76
  77 static const Test same_prog_multi_hook[] = {
  78         {
  79                 .option_name = "BPFProgram",
  80                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
  81                 .attach_type = BPF_CGROUP_INET_INGRESS,
  82                 .bpffs_path = BPFFS_PATH("trivial-skb"),
  83         },
  84         {
  85                 .option_name = "BPFProgram",
  86                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
  87                 .attach_type = BPF_CGROUP_INET_EGRESS,
  88                 .bpffs_path = BPFFS_PATH("trivial-skb"),
  89         }
  90 };
  91
  92 static const Test same_prog_multi_option_0[] = {
  93         {
  94                 .option_name = "BPFProgram",
  95                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
  96                 .attach_type = BPF_CGROUP_INET_INGRESS,
  97                 .bpffs_path = BPFFS_PATH("trivial-skb"),
  98         },
  99         {
 100                 .option_name = "IPIngressFilterPath",
 101                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
 102                 .attach_type = BPF_CGROUP_INET_INGRESS,
 103                 .bpffs_path = BPFFS_PATH("trivial-skb"),
 104         }
 105 };
 106
 107 static const Test same_prog_multi_option_1[] = {
 108         {
 109                 .option_name = "IPEgressFilterPath",
 110                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
 111                 .attach_type = BPF_CGROUP_INET_EGRESS,
 112                 .bpffs_path = BPFFS_PATH("trivial-skb"),
 113         },
 114         {
 115                 .option_name = "BPFProgram",
 116                 .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
 117                 .attach_type = BPF_CGROUP_INET_EGRESS,
 118                 .bpffs_path = BPFFS_PATH("trivial-skb"),
 119         }
 120 };
 121 #undef BPFFS_PATH
 122
 123 static int bpf_foreign_test_to_string(enum bpf_attach_type attach_type, const char *bpffs_path, char **ret_str) {
 124         const char *s = NULL;
 125
 126         assert_se(bpffs_path);
 127         assert_se(ret_str);
 128
 129         assert_se(s = bpf_cgroup_attach_type_to_string(attach_type));
 130         assert_se(*ret_str = strjoin(s, ":", bpffs_path));
 131
 132         return 0;
 133 }
 134
 135 static char **unlink_paths_and_free(char **paths) {
 136         STRV_FOREACH(i, paths)
 137                 (void) unlink(*i);
 138
 139         return strv_free(paths);
 140 }
 141
 142 DEFINE_TRIVIAL_CLEANUP_FUNC(char **, unlink_paths_and_free);
 143
 144 static int pin_programs(Unit *u, CGroupContext *cc, const Test *test_suite, size_t test_suite_size, char ***paths_ret) {
 145         _cleanup_(unlink_paths_and_freep) char **bpffs_paths = NULL;
 146         static const struct bpf_insn trivial[] = {
 147                 BPF_MOV64_IMM(BPF_REG_0, 0),
 148                 BPF_EXIT_INSN()
 149         };
 150         char log_buf[0xffff];
 151         int r;
 152
 153         assert_se(paths_ret);
 154
 155         for (size_t i = 0; i < test_suite_size; i++) {
 156                 _cleanup_(bpf_program_freep) BPFProgram *prog = NULL;
 157                 _cleanup_free_ char *str = NULL;
 158
 159                 r = bpf_foreign_test_to_string(test_suite[i].attach_type, test_suite[i].bpffs_path, &str);
 160                 if (r < 0)
 161                         return log_error_errno(r, "Failed to convert program to string");
 162
 163                 r = bpf_program_new(test_suite[i].prog_type, "sd_trivial", &prog);
 164                 if (r < 0)
 165                         return log_error_errno(r, "Failed to create program '%s'", str);
 166
 167                 r = bpf_program_add_instructions(prog, trivial, ELEMENTSOF(trivial));
 168                 if (r < 0)
 169                         return log_error_errno(r, "Failed to add trivial instructions for '%s'", str);
 170
 171                 r = bpf_program_load_kernel(prog, log_buf, ELEMENTSOF(log_buf));
 172                 if (r < 0)
 173                         return log_error_errno(r, "Failed to load BPF program '%s'", str);
 174
 175                 if (strv_contains(bpffs_paths, test_suite[i].bpffs_path))
 176                         continue;
 177
 178                 r = strv_extend(&bpffs_paths, test_suite[i].bpffs_path);
 179                 if (r < 0)
 180                         return log_error_errno(r, "Failed to put path into a vector: %m");
 181
 182                 r = bpf_program_pin(prog->kernel_fd, test_suite[i].bpffs_path);
 183                 if (r < 0)
 184                         return log_error_errno(r, "Failed to pin BPF program '%s'", str);
 185         }
 186
 187         *paths_ret = TAKE_PTR(bpffs_paths);
 188         return 0;
 189 }
 190
 191 static int test_bpf_cgroup_programs(Manager *m, const char *unit_name, const Test *test_suite, size_t test_suite_size) {
 192         _cleanup_(unlink_paths_and_freep) char **bpffs_paths = NULL;
 193         _cleanup_(unit_freep) Unit *u = NULL;
 194         CGroupContext *cc = NULL;
 195         int cld_code, r;
 196
 197         assert_se(u = unit_new(m, sizeof(Service)));
 198         assert_se(unit_add_name(u, unit_name) == 0);
 199         assert_se(cc = unit_get_cgroup_context(u));
 200
 201         r = pin_programs(u, cc, test_suite, test_suite_size, &bpffs_paths);
 202         if (r < 0)
 203                 return log_error_errno(r, "Failed to pin programs: %m");
 204
 205         for (size_t i = 0; i < test_suite_size; i++) {
 206                 if (streq(test_suite[i].option_name, "BPFProgram")) {
 207                         _cleanup_free_ char *option = NULL;
 208                         r = bpf_foreign_test_to_string(test_suite[i].attach_type, test_suite[i].bpffs_path, &option);
 209                         if (r < 0)
 210                                 return log_error_errno(r, "Failed to compose option string: %m");
 211                         r = config_parse_bpf_foreign_program(
 212                                         u->id, "filename", 1, "Service", 1, test_suite[i].option_name, 0, option, cc, u);
 213
 214                         if (r < 0)
 215                                 return log_error_errno(r, "Failed to parse option string '%s': %m", option);
 216                 } else if (STR_IN_SET(test_suite[i].option_name, "IPIngressFilterPath", "IPEgressFilterPath")) {
 217                         const char *option = test_suite[i].bpffs_path;
 218                         void *paths = NULL;
 219
 220                         if (streq(test_suite[i].option_name, "IPIngressFilterPath"))
 221                                 paths = &cc->ip_filters_ingress;
 222                         else
 223                                 paths = &cc->ip_filters_egress;
 224
 225                         r = config_parse_ip_filter_bpf_progs(
 226                                         u->id, "filename", 1, "Service", 1, test_suite[i].option_name, 0, option, paths, u);
 227                         if (r < 0)
 228                                 return log_error_errno(r, "Failed to parse option string '%s': %m", option);
 229                 }
 230         }
 231
 232         r = config_parse_exec(
 233                         u->id,
 234                         "filename",
 235                         1,
 236                         "Service",
 237                         1,
 238                         "ExecStart",
 239                         SERVICE_EXEC_START,
 240                         "-/bin/ping -c 5 127.0.0.1 -W 1",
 241                         SERVICE(u)->exec_command,
 242                         u);
 243         if (r < 0)
 244                 return log_error_errno(r, "Failed to parse ExecStart");
 245
 246         SERVICE(u)->type = SERVICE_ONESHOT;
 247         u->load_state = UNIT_LOADED;
 248
 249         r = unit_start(u);
 250         if (r < 0)
 251                 return log_error_errno(r, "Unit start failed %m");
 252
 253         while (!IN_SET(SERVICE(u)->state, SERVICE_DEAD, SERVICE_FAILED)) {
 254                 r = sd_event_run(m->event, UINT64_MAX);
 255                 if (r < 0)
 256                         return log_error_errno(errno, "Event run failed %m");
 257         }
 258
 259         cld_code = SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.code;
 260         if (cld_code != CLD_EXITED)
 261                 return log_error_errno(SYNTHETIC_ERRNO(EBUSY),
 262                                 "Child didn't exit normally, code='%s'", sigchld_code_to_string(cld_code));
 263
 264         if (SERVICE(u)->state != SERVICE_DEAD)
 265                 return log_error_errno(SYNTHETIC_ERRNO(EBUSY), "Service is not dead");
 266
 267         return r;
 268 }
 269
 270 int main(int argc, char *argv[]) {
 271         _cleanup_(rm_rf_physical_and_freep) char *runtime_dir = NULL;
 272         _cleanup_(manager_freep) Manager *m = NULL;
 273         _cleanup_free_ char *unit_dir = NULL;
 274         struct rlimit rl;
 275         int r;
 276
 277         test_setup_logging(LOG_DEBUG);
 278
 279         if (detect_container() > 0)
 280                 return log_tests_skipped("test-bpf fails inside LXC and Docker containers: https://github.com/systemd/systemd/issues/9666");
 281
 282         if (getuid() != 0)
 283                 return log_tests_skipped("not running as root");
 284
 285         assert_se(getrlimit(RLIMIT_MEMLOCK, &rl) >= 0);
 286         rl.rlim_cur = rl.rlim_max = MAX(rl.rlim_max, CAN_MEMLOCK_SIZE);
 287         (void) setrlimit_closest(RLIMIT_MEMLOCK, &rl);
 288
 289         if (!can_memlock())
 290                 return log_tests_skipped("Can't use mlock()");
 291
 292         r = cg_all_unified();
 293         if (r <= 0)
 294                 return log_tests_skipped("Unified hierarchy is required");
 295
 296         r = enter_cgroup_subroot(NULL);
 297         if (r == -ENOMEDIUM)
 298                 return log_tests_skipped("cgroupfs not available");
 299
 300         assert_se(get_testdata_dir("units", &unit_dir) >= 0);
 301         assert_se(set_unit_path(unit_dir) >= 0);
 302         assert_se(runtime_dir = setup_fake_runtime_dir());
 303
 304         assert_se(manager_new(UNIT_FILE_USER, MANAGER_TEST_RUN_BASIC, &m) >= 0);
 305         assert_se(manager_startup(m, NULL, NULL, NULL) >= 0);
 306
 307         assert_se(test_bpf_cgroup_programs(m,
 308                                 "single_prog.service", single_prog, ELEMENTSOF(single_prog)) >= 0);
 309         assert_se(test_bpf_cgroup_programs(m,
 310                                 "multi_prog_same_hook.service",
 311                                 multi_prog_same_hook, ELEMENTSOF(multi_prog_same_hook)) >= 0);
 312         assert_se(test_bpf_cgroup_programs(m,
 313                                 "same_prog_multi_hook.service",
 314                                 same_prog_multi_hook, ELEMENTSOF(same_prog_multi_hook)) >= 0);
 315         assert_se(test_bpf_cgroup_programs(m,
 316                                 "same_prog_multi_option_0.service",
 317                                 same_prog_multi_option_0, ELEMENTSOF(same_prog_multi_option_0)) >= 0);
 318         assert_se(test_bpf_cgroup_programs(m,
 319                                 "same_prog_multi_option_1.service",
 320                                 same_prog_multi_option_1, ELEMENTSOF(same_prog_multi_option_1)) >= 0);
 321         assert_se(test_bpf_cgroup_programs(m,
 322                                 "same_prog_same_hook.service",
 323                                 same_prog_same_hook,
 324                                 ELEMENTSOF(same_prog_same_hook)) >= 0);
 325         assert_se(test_bpf_cgroup_programs(m,
 326                                 "path_split_test.service",
 327                                 path_split_test,
 328                                 ELEMENTSOF(path_split_test)) >= 0);
 329         return 0;
 330 }