1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2019 Facebook */ 3 #include <test_progs.h> 4 #include <network_helpers.h> 5 #include <bpf/btf.h> 6 #include "bind4_prog.skel.h" 7 #include "freplace_progmap.skel.h" 8 #include "xdp_dummy.skel.h" 9 10 typedef int (*test_cb)(struct bpf_object *obj); 11 12 static int check_data_map(struct bpf_object *obj, int prog_cnt, bool reset) 13 { 14 struct bpf_map *data_map = NULL, *map; 15 __u64 *result = NULL; 16 const int zero = 0; 17 __u32 duration = 0; 18 int ret = -1, i; 19 20 result = malloc((prog_cnt + 32 /* spare */) * sizeof(__u64)); 21 if (CHECK(!result, "alloc_memory", "failed to alloc memory")) 22 return -ENOMEM; 23 24 bpf_object__for_each_map(map, obj) 25 if (bpf_map__is_internal(map)) { 26 data_map = map; 27 break; 28 } 29 if (CHECK(!data_map, "find_data_map", "data map not found\n")) 30 goto out; 31 32 ret = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, result); 33 if (CHECK(ret, "get_result", 34 "failed to get output data: %d\n", ret)) 35 goto out; 36 37 for (i = 0; i < prog_cnt; i++) { 38 if (CHECK(result[i] != 1, "result", 39 "fexit_bpf2bpf result[%d] failed err %llu\n", 40 i, result[i])) 41 goto out; 42 result[i] = 0; 43 } 44 if (reset) { 45 ret = bpf_map_update_elem(bpf_map__fd(data_map), &zero, result, 0); 46 if (CHECK(ret, "reset_result", "failed to reset result\n")) 47 goto out; 48 } 49 50 ret = 0; 51 out: 52 free(result); 53 return ret; 54 } 55 56 static void test_fexit_bpf2bpf_common(const char *obj_file, 57 const char *target_obj_file, 58 int prog_cnt, 59 const char **prog_name, 60 bool run_prog, 61 test_cb cb) 62 { 63 struct bpf_object *obj = NULL, *tgt_obj; 64 __u32 tgt_prog_id, info_len; 65 struct bpf_prog_info prog_info = {}; 66 struct bpf_program **prog = NULL, *p; 67 struct bpf_link **link = NULL; 68 int err, tgt_fd, i; 69 struct btf *btf; 70 LIBBPF_OPTS(bpf_test_run_opts, topts, 71 .data_in = &pkt_v6, 72 .data_size_in = sizeof(pkt_v6), 73 .repeat = 1, 74 ); 75 76 err = bpf_prog_test_load(target_obj_file, BPF_PROG_TYPE_UNSPEC, 77 &tgt_obj, &tgt_fd); 78 if (!ASSERT_OK(err, "tgt_prog_load")) 79 return; 80 81 info_len = sizeof(prog_info); 82 err = bpf_prog_get_info_by_fd(tgt_fd, &prog_info, &info_len); 83 if (!ASSERT_OK(err, "tgt_fd_get_info")) 84 goto close_prog; 85 86 tgt_prog_id = prog_info.id; 87 btf = bpf_object__btf(tgt_obj); 88 89 link = calloc(sizeof(struct bpf_link *), prog_cnt); 90 if (!ASSERT_OK_PTR(link, "link_ptr")) 91 goto close_prog; 92 93 prog = calloc(sizeof(struct bpf_program *), prog_cnt); 94 if (!ASSERT_OK_PTR(prog, "prog_ptr")) 95 goto close_prog; 96 97 obj = bpf_object__open_file(obj_file, NULL); 98 if (!ASSERT_OK_PTR(obj, "obj_open")) 99 goto close_prog; 100 101 bpf_object__for_each_program(p, obj) { 102 err = bpf_program__set_attach_target(p, tgt_fd, NULL); 103 ASSERT_OK(err, "set_attach_target"); 104 } 105 106 err = bpf_object__load(obj); 107 if (!ASSERT_OK(err, "obj_load")) 108 goto close_prog; 109 110 for (i = 0; i < prog_cnt; i++) { 111 struct bpf_link_info link_info; 112 struct bpf_program *pos; 113 const char *pos_sec_name; 114 const char *tgt_name; 115 __s32 btf_id; 116 117 tgt_name = strstr(prog_name[i], "/"); 118 if (!ASSERT_OK_PTR(tgt_name, "tgt_name")) 119 goto close_prog; 120 btf_id = btf__find_by_name_kind(btf, tgt_name + 1, BTF_KIND_FUNC); 121 122 prog[i] = NULL; 123 bpf_object__for_each_program(pos, obj) { 124 pos_sec_name = bpf_program__section_name(pos); 125 if (pos_sec_name && !strcmp(pos_sec_name, prog_name[i])) { 126 prog[i] = pos; 127 break; 128 } 129 } 130 if (!ASSERT_OK_PTR(prog[i], prog_name[i])) 131 goto close_prog; 132 133 link[i] = bpf_program__attach_trace(prog[i]); 134 if (!ASSERT_OK_PTR(link[i], "attach_trace")) 135 goto close_prog; 136 137 info_len = sizeof(link_info); 138 memset(&link_info, 0, sizeof(link_info)); 139 err = bpf_link_get_info_by_fd(bpf_link__fd(link[i]), 140 &link_info, &info_len); 141 ASSERT_OK(err, "link_fd_get_info"); 142 ASSERT_EQ(link_info.tracing.attach_type, 143 bpf_program__expected_attach_type(prog[i]), 144 "link_attach_type"); 145 ASSERT_EQ(link_info.tracing.target_obj_id, tgt_prog_id, "link_tgt_obj_id"); 146 ASSERT_EQ(link_info.tracing.target_btf_id, btf_id, "link_tgt_btf_id"); 147 } 148 149 if (cb) { 150 err = cb(obj); 151 if (err) 152 goto close_prog; 153 } 154 155 if (!run_prog) 156 goto close_prog; 157 158 err = bpf_prog_test_run_opts(tgt_fd, &topts); 159 ASSERT_OK(err, "prog_run"); 160 ASSERT_EQ(topts.retval, 0, "prog_run_ret"); 161 162 if (check_data_map(obj, prog_cnt, false)) 163 goto close_prog; 164 165 close_prog: 166 for (i = 0; i < prog_cnt; i++) 167 bpf_link__destroy(link[i]); 168 bpf_object__close(obj); 169 bpf_object__close(tgt_obj); 170 free(link); 171 free(prog); 172 } 173 174 static void test_target_no_callees(void) 175 { 176 const char *prog_name[] = { 177 "fexit/test_pkt_md_access", 178 }; 179 test_fexit_bpf2bpf_common("./fexit_bpf2bpf_simple.bpf.o", 180 "./test_pkt_md_access.bpf.o", 181 ARRAY_SIZE(prog_name), 182 prog_name, true, NULL); 183 } 184 185 static void test_target_yes_callees(void) 186 { 187 const char *prog_name[] = { 188 "fexit/test_pkt_access", 189 "fexit/test_pkt_access_subprog1", 190 "fexit/test_pkt_access_subprog2", 191 "fexit/test_pkt_access_subprog3", 192 }; 193 test_fexit_bpf2bpf_common("./fexit_bpf2bpf.bpf.o", 194 "./test_pkt_access.bpf.o", 195 ARRAY_SIZE(prog_name), 196 prog_name, true, NULL); 197 } 198 199 static void test_func_replace(void) 200 { 201 const char *prog_name[] = { 202 "fexit/test_pkt_access", 203 "fexit/test_pkt_access_subprog1", 204 "fexit/test_pkt_access_subprog2", 205 "fexit/test_pkt_access_subprog3", 206 "freplace/get_skb_len", 207 "freplace/get_skb_ifindex", 208 "freplace/get_constant", 209 "freplace/test_pkt_write_access_subprog", 210 }; 211 test_fexit_bpf2bpf_common("./fexit_bpf2bpf.bpf.o", 212 "./test_pkt_access.bpf.o", 213 ARRAY_SIZE(prog_name), 214 prog_name, true, NULL); 215 } 216 217 static void test_func_replace_verify(void) 218 { 219 const char *prog_name[] = { 220 "freplace/do_bind", 221 }; 222 test_fexit_bpf2bpf_common("./freplace_connect4.bpf.o", 223 "./connect4_prog.bpf.o", 224 ARRAY_SIZE(prog_name), 225 prog_name, false, NULL); 226 } 227 228 static int test_second_attach(struct bpf_object *obj) 229 { 230 const char *prog_name = "security_new_get_constant"; 231 const char *tgt_name = "get_constant"; 232 const char *tgt_obj_file = "./test_pkt_access.bpf.o"; 233 struct bpf_program *prog = NULL; 234 struct bpf_object *tgt_obj; 235 struct bpf_link *link; 236 int err = 0, tgt_fd; 237 LIBBPF_OPTS(bpf_test_run_opts, topts, 238 .data_in = &pkt_v6, 239 .data_size_in = sizeof(pkt_v6), 240 .repeat = 1, 241 ); 242 243 prog = bpf_object__find_program_by_name(obj, prog_name); 244 if (!ASSERT_OK_PTR(prog, "find_prog")) 245 return -ENOENT; 246 247 err = bpf_prog_test_load(tgt_obj_file, BPF_PROG_TYPE_UNSPEC, 248 &tgt_obj, &tgt_fd); 249 if (!ASSERT_OK(err, "second_prog_load")) 250 return err; 251 252 link = bpf_program__attach_freplace(prog, tgt_fd, tgt_name); 253 if (!ASSERT_OK_PTR(link, "second_link")) 254 goto out; 255 256 err = bpf_prog_test_run_opts(tgt_fd, &topts); 257 if (!ASSERT_OK(err, "ipv6 test_run")) 258 goto out; 259 if (!ASSERT_OK(topts.retval, "ipv6 retval")) 260 goto out; 261 262 err = check_data_map(obj, 1, true); 263 if (err) 264 goto out; 265 266 out: 267 bpf_link__destroy(link); 268 bpf_object__close(tgt_obj); 269 return err; 270 } 271 272 static void test_func_replace_multi(void) 273 { 274 const char *prog_name[] = { 275 "freplace/get_constant", 276 }; 277 test_fexit_bpf2bpf_common("./freplace_get_constant.bpf.o", 278 "./test_pkt_access.bpf.o", 279 ARRAY_SIZE(prog_name), 280 prog_name, true, test_second_attach); 281 } 282 283 static void test_fmod_ret_freplace(void) 284 { 285 struct bpf_object *freplace_obj = NULL, *pkt_obj, *fmod_obj = NULL; 286 const char *freplace_name = "./freplace_get_constant.bpf.o"; 287 const char *fmod_ret_name = "./fmod_ret_freplace.bpf.o"; 288 DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts); 289 const char *tgt_name = "./test_pkt_access.bpf.o"; 290 struct bpf_link *freplace_link = NULL; 291 struct bpf_program *prog; 292 __u32 duration = 0; 293 int err, pkt_fd, attach_prog_fd; 294 295 err = bpf_prog_test_load(tgt_name, BPF_PROG_TYPE_UNSPEC, 296 &pkt_obj, &pkt_fd); 297 /* the target prog should load fine */ 298 if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n", 299 tgt_name, err, errno)) 300 return; 301 302 freplace_obj = bpf_object__open_file(freplace_name, NULL); 303 if (!ASSERT_OK_PTR(freplace_obj, "freplace_obj_open")) 304 goto out; 305 306 prog = bpf_object__next_program(freplace_obj, NULL); 307 err = bpf_program__set_attach_target(prog, pkt_fd, NULL); 308 ASSERT_OK(err, "freplace__set_attach_target"); 309 310 err = bpf_object__load(freplace_obj); 311 if (CHECK(err, "freplace_obj_load", "err %d\n", err)) 312 goto out; 313 314 freplace_link = bpf_program__attach_trace(prog); 315 if (!ASSERT_OK_PTR(freplace_link, "freplace_attach_trace")) 316 goto out; 317 318 fmod_obj = bpf_object__open_file(fmod_ret_name, NULL); 319 if (!ASSERT_OK_PTR(fmod_obj, "fmod_obj_open")) 320 goto out; 321 322 attach_prog_fd = bpf_program__fd(prog); 323 prog = bpf_object__next_program(fmod_obj, NULL); 324 err = bpf_program__set_attach_target(prog, attach_prog_fd, NULL); 325 ASSERT_OK(err, "fmod_ret_set_attach_target"); 326 327 err = bpf_object__load(fmod_obj); 328 if (CHECK(!err, "fmod_obj_load", "loading fmod_ret should fail\n")) 329 goto out; 330 331 out: 332 bpf_link__destroy(freplace_link); 333 bpf_object__close(freplace_obj); 334 bpf_object__close(fmod_obj); 335 bpf_object__close(pkt_obj); 336 } 337 338 static void test_func_replace_void(void) 339 { 340 const char *prog_name[] = { 341 "freplace/foo", 342 }; 343 test_fexit_bpf2bpf_common("./freplace_void.bpf.o", 344 "./test_global_func7.bpf.o", 345 ARRAY_SIZE(prog_name), 346 prog_name, false, NULL); 347 } 348 349 static void test_obj_load_failure_common(const char *obj_file, 350 const char *target_obj_file, 351 const char *exp_msg) 352 { 353 /* 354 * standalone test that asserts failure to load freplace prog 355 * because of invalid return code. 356 */ 357 struct bpf_object *obj = NULL, *pkt_obj; 358 struct bpf_program *prog; 359 char log_buf[64 * 1024]; 360 int err, pkt_fd; 361 __u32 duration = 0; 362 363 err = bpf_prog_test_load(target_obj_file, BPF_PROG_TYPE_UNSPEC, 364 &pkt_obj, &pkt_fd); 365 /* the target prog should load fine */ 366 if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n", 367 target_obj_file, err, errno)) 368 return; 369 370 obj = bpf_object__open_file(obj_file, NULL); 371 if (!ASSERT_OK_PTR(obj, "obj_open")) 372 goto close_prog; 373 374 prog = bpf_object__next_program(obj, NULL); 375 err = bpf_program__set_attach_target(prog, pkt_fd, NULL); 376 ASSERT_OK(err, "set_attach_target"); 377 378 log_buf[0] = '\0'; 379 if (exp_msg) 380 bpf_program__set_log_buf(prog, log_buf, sizeof(log_buf)); 381 if (env.verbosity > VERBOSE_NONE) 382 bpf_program__set_log_level(prog, 2); 383 384 /* It should fail to load the program */ 385 err = bpf_object__load(obj); 386 if (env.verbosity > VERBOSE_NONE && exp_msg) /* we overtook log */ 387 printf("VERIFIER LOG:\n================\n%s\n================\n", log_buf); 388 if (CHECK(!err, "bpf_obj_load should fail", "err %d\n", err)) 389 goto close_prog; 390 391 if (exp_msg) 392 ASSERT_HAS_SUBSTR(log_buf, exp_msg, "fail_msg"); 393 close_prog: 394 bpf_object__close(obj); 395 bpf_object__close(pkt_obj); 396 } 397 398 static void test_func_replace_return_code(void) 399 { 400 /* test invalid return code in the replaced program */ 401 test_obj_load_failure_common("./freplace_connect_v4_prog.bpf.o", 402 "./connect4_prog.bpf.o", NULL); 403 } 404 405 static void test_func_map_prog_compatibility(void) 406 { 407 /* test with spin lock map value in the replaced program */ 408 test_obj_load_failure_common("./freplace_attach_probe.bpf.o", 409 "./test_attach_probe.bpf.o", NULL); 410 } 411 412 static void test_func_replace_unreliable(void) 413 { 414 /* freplace'ing unreliable main prog should fail with error 415 * "Cannot replace static functions" 416 */ 417 test_obj_load_failure_common("freplace_unreliable_prog.bpf.o", 418 "./verifier_btf_unreliable_prog.bpf.o", 419 "Cannot replace static functions"); 420 } 421 422 static void test_func_replace_global_func(void) 423 { 424 const char *prog_name[] = { 425 "freplace/test_pkt_access", 426 }; 427 428 test_fexit_bpf2bpf_common("./freplace_global_func.bpf.o", 429 "./test_pkt_access.bpf.o", 430 ARRAY_SIZE(prog_name), 431 prog_name, false, NULL); 432 } 433 434 static void test_func_replace_int_with_void(void) 435 { 436 /* Make sure we can't freplace with the wrong type */ 437 test_obj_load_failure_common("freplace_int_with_void.bpf.o", 438 "./test_global_func2.bpf.o", 439 "Return type UNKNOWN of test_freplace_int_with_void()" 440 " doesn't match type INT of global_func2()"); 441 } 442 443 static int find_prog_btf_id(const char *name, __u32 attach_prog_fd) 444 { 445 struct bpf_prog_info info = {}; 446 __u32 info_len = sizeof(info); 447 struct btf *btf; 448 int ret; 449 450 ret = bpf_prog_get_info_by_fd(attach_prog_fd, &info, &info_len); 451 if (ret) 452 return ret; 453 454 if (!info.btf_id) 455 return -EINVAL; 456 457 btf = btf__load_from_kernel_by_id(info.btf_id); 458 ret = libbpf_get_error(btf); 459 if (ret) 460 return ret; 461 462 ret = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); 463 btf__free(btf); 464 return ret; 465 } 466 467 static int load_fentry(int attach_prog_fd, int attach_btf_id) 468 { 469 LIBBPF_OPTS(bpf_prog_load_opts, opts, 470 .expected_attach_type = BPF_TRACE_FENTRY, 471 .attach_prog_fd = attach_prog_fd, 472 .attach_btf_id = attach_btf_id, 473 ); 474 struct bpf_insn insns[] = { 475 BPF_MOV64_IMM(BPF_REG_0, 0), 476 BPF_EXIT_INSN(), 477 }; 478 479 return bpf_prog_load(BPF_PROG_TYPE_TRACING, 480 "bind4_fentry", 481 "GPL", 482 insns, 483 ARRAY_SIZE(insns), 484 &opts); 485 } 486 487 static void test_fentry_to_cgroup_bpf(void) 488 { 489 struct bind4_prog *skel = NULL; 490 struct bpf_prog_info info = {}; 491 __u32 info_len = sizeof(info); 492 int cgroup_fd = -1; 493 int fentry_fd = -1; 494 int btf_id; 495 496 cgroup_fd = test__join_cgroup("/fentry_to_cgroup_bpf"); 497 if (!ASSERT_GE(cgroup_fd, 0, "cgroup_fd")) 498 return; 499 500 skel = bind4_prog__open_and_load(); 501 if (!ASSERT_OK_PTR(skel, "skel")) 502 goto cleanup; 503 504 skel->links.bind_v4_prog = bpf_program__attach_cgroup(skel->progs.bind_v4_prog, cgroup_fd); 505 if (!ASSERT_OK_PTR(skel->links.bind_v4_prog, "bpf_program__attach_cgroup")) 506 goto cleanup; 507 508 btf_id = find_prog_btf_id("bind_v4_prog", bpf_program__fd(skel->progs.bind_v4_prog)); 509 if (!ASSERT_GE(btf_id, 0, "find_prog_btf_id")) 510 goto cleanup; 511 512 fentry_fd = load_fentry(bpf_program__fd(skel->progs.bind_v4_prog), btf_id); 513 if (!ASSERT_GE(fentry_fd, 0, "load_fentry")) 514 goto cleanup; 515 516 /* Make sure bpf_prog_get_info_by_fd works correctly when attaching 517 * to another BPF program. 518 */ 519 520 ASSERT_OK(bpf_prog_get_info_by_fd(fentry_fd, &info, &info_len), 521 "bpf_prog_get_info_by_fd"); 522 523 ASSERT_EQ(info.btf_id, 0, "info.btf_id"); 524 ASSERT_EQ(info.attach_btf_id, btf_id, "info.attach_btf_id"); 525 ASSERT_GT(info.attach_btf_obj_id, 0, "info.attach_btf_obj_id"); 526 527 cleanup: 528 if (cgroup_fd >= 0) 529 close(cgroup_fd); 530 if (fentry_fd >= 0) 531 close(fentry_fd); 532 bind4_prog__destroy(skel); 533 } 534 535 static void test_func_replace_progmap(void) 536 { 537 struct bpf_cpumap_val value = { .qsize = 1 }; 538 struct freplace_progmap *skel = NULL; 539 struct xdp_dummy *tgt_skel = NULL; 540 __u32 key = 0; 541 int err; 542 543 skel = freplace_progmap__open(); 544 if (!ASSERT_OK_PTR(skel, "prog_open")) 545 return; 546 547 tgt_skel = xdp_dummy__open_and_load(); 548 if (!ASSERT_OK_PTR(tgt_skel, "tgt_prog_load")) 549 goto out; 550 551 err = bpf_program__set_attach_target(skel->progs.xdp_cpumap_prog, 552 bpf_program__fd(tgt_skel->progs.xdp_dummy_prog), 553 "xdp_dummy_prog"); 554 if (!ASSERT_OK(err, "set_attach_target")) 555 goto out; 556 557 err = freplace_progmap__load(skel); 558 if (!ASSERT_OK(err, "obj_load")) 559 goto out; 560 561 /* Prior to fixing the kernel, loading the PROG_TYPE_EXT 'redirect' 562 * program above will cause the map owner type of 'cpumap' to be set to 563 * PROG_TYPE_EXT. This in turn will cause the bpf_map_update_elem() 564 * below to fail, because the program we are inserting into the map is 565 * of PROG_TYPE_XDP. After fixing the kernel, the initial ownership will 566 * be correctly resolved to the *target* of the PROG_TYPE_EXT program 567 * (i.e., PROG_TYPE_XDP) and the map update will succeed. 568 */ 569 value.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_drop_prog); 570 err = bpf_map_update_elem(bpf_map__fd(skel->maps.cpu_map), 571 &key, &value, 0); 572 ASSERT_OK(err, "map_update"); 573 574 out: 575 xdp_dummy__destroy(tgt_skel); 576 freplace_progmap__destroy(skel); 577 } 578 579 /* NOTE: affect other tests, must run in serial mode */ 580 void serial_test_fexit_bpf2bpf(void) 581 { 582 if (test__start_subtest("target_no_callees")) 583 test_target_no_callees(); 584 if (test__start_subtest("target_yes_callees")) 585 test_target_yes_callees(); 586 if (test__start_subtest("func_replace")) 587 test_func_replace(); 588 if (test__start_subtest("func_replace_verify")) 589 test_func_replace_verify(); 590 if (test__start_subtest("func_replace_return_code")) 591 test_func_replace_return_code(); 592 if (test__start_subtest("func_map_prog_compatibility")) 593 test_func_map_prog_compatibility(); 594 if (test__start_subtest("func_replace_unreliable")) 595 test_func_replace_unreliable(); 596 if (test__start_subtest("func_replace_multi")) 597 test_func_replace_multi(); 598 if (test__start_subtest("fmod_ret_freplace")) 599 test_fmod_ret_freplace(); 600 if (test__start_subtest("func_replace_global_func")) 601 test_func_replace_global_func(); 602 if (test__start_subtest("fentry_to_cgroup_bpf")) 603 test_fentry_to_cgroup_bpf(); 604 if (test__start_subtest("func_replace_progmap")) 605 test_func_replace_progmap(); 606 if (test__start_subtest("freplace_int_with_void")) 607 test_func_replace_int_with_void(); 608 if (test__start_subtest("freplace_void")) 609 test_func_replace_void(); 610 } 611