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
10typedef int (*test_cb)(struct bpf_object *obj);
11
12static 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;
51out:
52	free(result);
53	return ret;
54}
55
56static 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
165close_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
174static 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
185static 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
199static 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
217static 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
228static 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
266out:
267	bpf_link__destroy(link);
268	bpf_object__close(tgt_obj);
269	return err;
270}
271
272static 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
283static 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
331out:
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
339static 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
350static 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");
394close_prog:
395	bpf_object__close(obj);
396	bpf_object__close(pkt_obj);
397}
398
399static 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
406static 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
413static 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
423static 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
435static 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
459static 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
479static 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
519cleanup:
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
527static 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
566out:
567	xdp_dummy__destroy(tgt_skel);
568	freplace_progmap__destroy(skel);
569}
570
571/* NOTE: affect other tests, must run in serial mode */
572void 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