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
check_data_map(struct bpf_object * obj,int prog_cnt,bool reset)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
test_fexit_bpf2bpf_common(const char * obj_file,const char * target_obj_file,int prog_cnt,const char ** prog_name,bool run_prog,test_cb cb)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 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
test_target_no_callees(void)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
test_target_yes_callees(void)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
test_func_replace(void)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
test_func_replace_verify(void)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
test_second_attach(struct bpf_object * obj)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
test_func_replace_multi(void)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
test_fmod_ret_freplace(void)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
test_func_sockmap_update(void)339 static void test_func_sockmap_update(void)
340 {
341 const char *prog_name[] = {
342 "freplace/cls_redirect",
343 };
344 test_fexit_bpf2bpf_common("./freplace_cls_redirect.bpf.o",
345 "./test_cls_redirect.bpf.o",
346 ARRAY_SIZE(prog_name),
347 prog_name, false, NULL);
348 }
349
test_obj_load_failure_common(const char * obj_file,const char * target_obj_file,const char * exp_msg)350 static void test_obj_load_failure_common(const char *obj_file,
351 const char *target_obj_file,
352 const char *exp_msg)
353 {
354 /*
355 * standalone test that asserts failure to load freplace prog
356 * because of invalid return code.
357 */
358 struct bpf_object *obj = NULL, *pkt_obj;
359 struct bpf_program *prog;
360 char log_buf[64 * 1024];
361 int err, pkt_fd;
362 __u32 duration = 0;
363
364 err = bpf_prog_test_load(target_obj_file, BPF_PROG_TYPE_UNSPEC,
365 &pkt_obj, &pkt_fd);
366 /* the target prog should load fine */
367 if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n",
368 target_obj_file, err, errno))
369 return;
370
371 obj = bpf_object__open_file(obj_file, NULL);
372 if (!ASSERT_OK_PTR(obj, "obj_open"))
373 goto close_prog;
374
375 prog = bpf_object__next_program(obj, NULL);
376 err = bpf_program__set_attach_target(prog, pkt_fd, NULL);
377 ASSERT_OK(err, "set_attach_target");
378
379 log_buf[0] = '\0';
380 if (exp_msg)
381 bpf_program__set_log_buf(prog, log_buf, sizeof(log_buf));
382 if (env.verbosity > VERBOSE_NONE)
383 bpf_program__set_log_level(prog, 2);
384
385 /* It should fail to load the program */
386 err = bpf_object__load(obj);
387 if (env.verbosity > VERBOSE_NONE && exp_msg) /* we overtook log */
388 printf("VERIFIER LOG:\n================\n%s\n================\n", log_buf);
389 if (CHECK(!err, "bpf_obj_load should fail", "err %d\n", err))
390 goto close_prog;
391
392 if (exp_msg)
393 ASSERT_HAS_SUBSTR(log_buf, exp_msg, "fail_msg");
394 close_prog:
395 bpf_object__close(obj);
396 bpf_object__close(pkt_obj);
397 }
398
test_func_replace_return_code(void)399 static void test_func_replace_return_code(void)
400 {
401 /* test invalid return code in the replaced program */
402 test_obj_load_failure_common("./freplace_connect_v4_prog.bpf.o",
403 "./connect4_prog.bpf.o", NULL);
404 }
405
test_func_map_prog_compatibility(void)406 static void test_func_map_prog_compatibility(void)
407 {
408 /* test with spin lock map value in the replaced program */
409 test_obj_load_failure_common("./freplace_attach_probe.bpf.o",
410 "./test_attach_probe.bpf.o", NULL);
411 }
412
test_func_replace_unreliable(void)413 static void test_func_replace_unreliable(void)
414 {
415 /* freplace'ing unreliable main prog should fail with error
416 * "Cannot replace static functions"
417 */
418 test_obj_load_failure_common("freplace_unreliable_prog.bpf.o",
419 "./verifier_btf_unreliable_prog.bpf.o",
420 "Cannot replace static functions");
421 }
422
test_func_replace_global_func(void)423 static void test_func_replace_global_func(void)
424 {
425 const char *prog_name[] = {
426 "freplace/test_pkt_access",
427 };
428
429 test_fexit_bpf2bpf_common("./freplace_global_func.bpf.o",
430 "./test_pkt_access.bpf.o",
431 ARRAY_SIZE(prog_name),
432 prog_name, false, NULL);
433 }
434
find_prog_btf_id(const char * name,__u32 attach_prog_fd)435 static int find_prog_btf_id(const char *name, __u32 attach_prog_fd)
436 {
437 struct bpf_prog_info info = {};
438 __u32 info_len = sizeof(info);
439 struct btf *btf;
440 int ret;
441
442 ret = bpf_prog_get_info_by_fd(attach_prog_fd, &info, &info_len);
443 if (ret)
444 return ret;
445
446 if (!info.btf_id)
447 return -EINVAL;
448
449 btf = btf__load_from_kernel_by_id(info.btf_id);
450 ret = libbpf_get_error(btf);
451 if (ret)
452 return ret;
453
454 ret = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC);
455 btf__free(btf);
456 return ret;
457 }
458
load_fentry(int attach_prog_fd,int attach_btf_id)459 static int load_fentry(int attach_prog_fd, int attach_btf_id)
460 {
461 LIBBPF_OPTS(bpf_prog_load_opts, opts,
462 .expected_attach_type = BPF_TRACE_FENTRY,
463 .attach_prog_fd = attach_prog_fd,
464 .attach_btf_id = attach_btf_id,
465 );
466 struct bpf_insn insns[] = {
467 BPF_MOV64_IMM(BPF_REG_0, 0),
468 BPF_EXIT_INSN(),
469 };
470
471 return bpf_prog_load(BPF_PROG_TYPE_TRACING,
472 "bind4_fentry",
473 "GPL",
474 insns,
475 ARRAY_SIZE(insns),
476 &opts);
477 }
478
test_fentry_to_cgroup_bpf(void)479 static void test_fentry_to_cgroup_bpf(void)
480 {
481 struct bind4_prog *skel = NULL;
482 struct bpf_prog_info info = {};
483 __u32 info_len = sizeof(info);
484 int cgroup_fd = -1;
485 int fentry_fd = -1;
486 int btf_id;
487
488 cgroup_fd = test__join_cgroup("/fentry_to_cgroup_bpf");
489 if (!ASSERT_GE(cgroup_fd, 0, "cgroup_fd"))
490 return;
491
492 skel = bind4_prog__open_and_load();
493 if (!ASSERT_OK_PTR(skel, "skel"))
494 goto cleanup;
495
496 skel->links.bind_v4_prog = bpf_program__attach_cgroup(skel->progs.bind_v4_prog, cgroup_fd);
497 if (!ASSERT_OK_PTR(skel->links.bind_v4_prog, "bpf_program__attach_cgroup"))
498 goto cleanup;
499
500 btf_id = find_prog_btf_id("bind_v4_prog", bpf_program__fd(skel->progs.bind_v4_prog));
501 if (!ASSERT_GE(btf_id, 0, "find_prog_btf_id"))
502 goto cleanup;
503
504 fentry_fd = load_fentry(bpf_program__fd(skel->progs.bind_v4_prog), btf_id);
505 if (!ASSERT_GE(fentry_fd, 0, "load_fentry"))
506 goto cleanup;
507
508 /* Make sure bpf_prog_get_info_by_fd works correctly when attaching
509 * to another BPF program.
510 */
511
512 ASSERT_OK(bpf_prog_get_info_by_fd(fentry_fd, &info, &info_len),
513 "bpf_prog_get_info_by_fd");
514
515 ASSERT_EQ(info.btf_id, 0, "info.btf_id");
516 ASSERT_EQ(info.attach_btf_id, btf_id, "info.attach_btf_id");
517 ASSERT_GT(info.attach_btf_obj_id, 0, "info.attach_btf_obj_id");
518
519 cleanup:
520 if (cgroup_fd >= 0)
521 close(cgroup_fd);
522 if (fentry_fd >= 0)
523 close(fentry_fd);
524 bind4_prog__destroy(skel);
525 }
526
test_func_replace_progmap(void)527 static void test_func_replace_progmap(void)
528 {
529 struct bpf_cpumap_val value = { .qsize = 1 };
530 struct freplace_progmap *skel = NULL;
531 struct xdp_dummy *tgt_skel = NULL;
532 __u32 key = 0;
533 int err;
534
535 skel = freplace_progmap__open();
536 if (!ASSERT_OK_PTR(skel, "prog_open"))
537 return;
538
539 tgt_skel = xdp_dummy__open_and_load();
540 if (!ASSERT_OK_PTR(tgt_skel, "tgt_prog_load"))
541 goto out;
542
543 err = bpf_program__set_attach_target(skel->progs.xdp_cpumap_prog,
544 bpf_program__fd(tgt_skel->progs.xdp_dummy_prog),
545 "xdp_dummy_prog");
546 if (!ASSERT_OK(err, "set_attach_target"))
547 goto out;
548
549 err = freplace_progmap__load(skel);
550 if (!ASSERT_OK(err, "obj_load"))
551 goto out;
552
553 /* Prior to fixing the kernel, loading the PROG_TYPE_EXT 'redirect'
554 * program above will cause the map owner type of 'cpumap' to be set to
555 * PROG_TYPE_EXT. This in turn will cause the bpf_map_update_elem()
556 * below to fail, because the program we are inserting into the map is
557 * of PROG_TYPE_XDP. After fixing the kernel, the initial ownership will
558 * be correctly resolved to the *target* of the PROG_TYPE_EXT program
559 * (i.e., PROG_TYPE_XDP) and the map update will succeed.
560 */
561 value.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_drop_prog);
562 err = bpf_map_update_elem(bpf_map__fd(skel->maps.cpu_map),
563 &key, &value, 0);
564 ASSERT_OK(err, "map_update");
565
566 out:
567 xdp_dummy__destroy(tgt_skel);
568 freplace_progmap__destroy(skel);
569 }
570
571 /* NOTE: affect other tests, must run in serial mode */
serial_test_fexit_bpf2bpf(void)572 void serial_test_fexit_bpf2bpf(void)
573 {
574 if (test__start_subtest("target_no_callees"))
575 test_target_no_callees();
576 if (test__start_subtest("target_yes_callees"))
577 test_target_yes_callees();
578 if (test__start_subtest("func_replace"))
579 test_func_replace();
580 if (test__start_subtest("func_replace_verify"))
581 test_func_replace_verify();
582 if (test__start_subtest("func_sockmap_update"))
583 test_func_sockmap_update();
584 if (test__start_subtest("func_replace_return_code"))
585 test_func_replace_return_code();
586 if (test__start_subtest("func_map_prog_compatibility"))
587 test_func_map_prog_compatibility();
588 if (test__start_subtest("func_replace_unreliable"))
589 test_func_replace_unreliable();
590 if (test__start_subtest("func_replace_multi"))
591 test_func_replace_multi();
592 if (test__start_subtest("fmod_ret_freplace"))
593 test_fmod_ret_freplace();
594 if (test__start_subtest("func_replace_global_func"))
595 test_func_replace_global_func();
596 if (test__start_subtest("fentry_to_cgroup_bpf"))
597 test_fentry_to_cgroup_bpf();
598 if (test__start_subtest("func_replace_progmap"))
599 test_func_replace_progmap();
600 }
601