1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (c) 2021 Facebook */
  3#include <test_progs.h>
  4#include <network_helpers.h>
  5#include "kfunc_call_fail.skel.h"
  6#include "kfunc_call_test.skel.h"
  7#include "kfunc_call_test.lskel.h"
  8#include "kfunc_call_test_subprog.skel.h"
  9#include "kfunc_call_test_subprog.lskel.h"
 10#include "kfunc_call_destructive.skel.h"
 11
 12#include "cap_helpers.h"
 13
 14static size_t log_buf_sz = 1048576; /* 1 MB */
 15static char obj_log_buf[1048576];
 16
 17enum kfunc_test_type {
 18	tc_test = 0,
 19	syscall_test,
 20	syscall_null_ctx_test,
 21};
 22
 23struct kfunc_test_params {
 24	const char *prog_name;
 25	unsigned long lskel_prog_desc_offset;
 26	int retval;
 27	enum kfunc_test_type test_type;
 28	const char *expected_err_msg;
 29};
 30
 31#define __BPF_TEST_SUCCESS(name, __retval, type) \
 32	{ \
 33	  .prog_name = #name, \
 34	  .lskel_prog_desc_offset = offsetof(struct kfunc_call_test_lskel, progs.name), \
 35	  .retval = __retval, \
 36	  .test_type = type, \
 37	  .expected_err_msg = NULL, \
 38	}
 39
 40#define __BPF_TEST_FAIL(name, __retval, type, error_msg) \
 41	{ \
 42	  .prog_name = #name, \
 43	  .lskel_prog_desc_offset = 0 /* unused when test is failing */, \
 44	  .retval = __retval, \
 45	  .test_type = type, \
 46	  .expected_err_msg = error_msg, \
 47	}
 48
 49#define TC_TEST(name, retval) __BPF_TEST_SUCCESS(name, retval, tc_test)
 50#define SYSCALL_TEST(name, retval) __BPF_TEST_SUCCESS(name, retval, syscall_test)
 51#define SYSCALL_NULL_CTX_TEST(name, retval) __BPF_TEST_SUCCESS(name, retval, syscall_null_ctx_test)
 52
 53#define TC_FAIL(name, retval, error_msg) __BPF_TEST_FAIL(name, retval, tc_test, error_msg)
 54#define SYSCALL_NULL_CTX_FAIL(name, retval, error_msg) \
 55	__BPF_TEST_FAIL(name, retval, syscall_null_ctx_test, error_msg)
 56
 57static struct kfunc_test_params kfunc_tests[] = {
 58	/* failure cases:
 59	 * if retval is 0 -> the program will fail to load and the error message is an error
 60	 * if retval is not 0 -> the program can be loaded but running it will gives the
 61	 *                       provided return value. The error message is thus the one
 62	 *                       from a successful load
 63	 */
 64	SYSCALL_NULL_CTX_FAIL(kfunc_syscall_test_fail, -EINVAL, "processed 4 insns"),
 65	SYSCALL_NULL_CTX_FAIL(kfunc_syscall_test_null_fail, -EINVAL, "processed 4 insns"),
 66	TC_FAIL(kfunc_call_test_get_mem_fail_rdonly, 0, "R0 cannot write into rdonly_mem"),
 67	TC_FAIL(kfunc_call_test_get_mem_fail_use_after_free, 0, "invalid mem access 'scalar'"),
 68	TC_FAIL(kfunc_call_test_get_mem_fail_oob, 0, "min value is outside of the allowed memory range"),
 69	TC_FAIL(kfunc_call_test_get_mem_fail_not_const, 0, "is not a const"),
 70	TC_FAIL(kfunc_call_test_mem_acquire_fail, 0, "acquire kernel function does not return PTR_TO_BTF_ID"),
 71
 72	/* success cases */
 73	TC_TEST(kfunc_call_test1, 12),
 74	TC_TEST(kfunc_call_test2, 3),
 75	TC_TEST(kfunc_call_test_ref_btf_id, 0),
 76	TC_TEST(kfunc_call_test_get_mem, 42),
 77	SYSCALL_TEST(kfunc_syscall_test, 0),
 78	SYSCALL_NULL_CTX_TEST(kfunc_syscall_test_null, 0),
 79};
 80
 81struct syscall_test_args {
 82	__u8 data[16];
 83	size_t size;
 84};
 85
 86static void verify_success(struct kfunc_test_params *param)
 87{
 88	struct kfunc_call_test_lskel *lskel = NULL;
 89	LIBBPF_OPTS(bpf_test_run_opts, topts);
 90	struct bpf_prog_desc *lskel_prog;
 91	struct kfunc_call_test *skel;
 92	struct bpf_program *prog;
 93	int prog_fd, err;
 94	struct syscall_test_args args = {
 95		.size = 10,
 96	};
 97
 98	switch (param->test_type) {
 99	case syscall_test:
100		topts.ctx_in = &args;
101		topts.ctx_size_in = sizeof(args);
102		/* fallthrough */
103	case syscall_null_ctx_test:
104		break;
105	case tc_test:
106		topts.data_in = &pkt_v4;
107		topts.data_size_in = sizeof(pkt_v4);
108		topts.repeat = 1;
109		break;
110	}
111
112	/* first test with normal libbpf */
113	skel = kfunc_call_test__open_and_load();
114	if (!ASSERT_OK_PTR(skel, "skel"))
115		return;
116
117	prog = bpf_object__find_program_by_name(skel->obj, param->prog_name);
118	if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
119		goto cleanup;
120
121	prog_fd = bpf_program__fd(prog);
122	err = bpf_prog_test_run_opts(prog_fd, &topts);
123	if (!ASSERT_OK(err, param->prog_name))
124		goto cleanup;
125
126	if (!ASSERT_EQ(topts.retval, param->retval, "retval"))
127		goto cleanup;
128
129	/* second test with light skeletons */
130	lskel = kfunc_call_test_lskel__open_and_load();
131	if (!ASSERT_OK_PTR(lskel, "lskel"))
132		goto cleanup;
133
134	lskel_prog = (struct bpf_prog_desc *)((char *)lskel + param->lskel_prog_desc_offset);
135
136	prog_fd = lskel_prog->prog_fd;
137	err = bpf_prog_test_run_opts(prog_fd, &topts);
138	if (!ASSERT_OK(err, param->prog_name))
139		goto cleanup;
140
141	ASSERT_EQ(topts.retval, param->retval, "retval");
142
143cleanup:
144	kfunc_call_test__destroy(skel);
145	if (lskel)
146		kfunc_call_test_lskel__destroy(lskel);
147}
148
149static void verify_fail(struct kfunc_test_params *param)
150{
151	LIBBPF_OPTS(bpf_object_open_opts, opts);
152	LIBBPF_OPTS(bpf_test_run_opts, topts);
153	struct bpf_program *prog;
154	struct kfunc_call_fail *skel;
155	int prog_fd, err;
156	struct syscall_test_args args = {
157		.size = 10,
158	};
159
160	opts.kernel_log_buf = obj_log_buf;
161	opts.kernel_log_size = log_buf_sz;
162	opts.kernel_log_level = 1;
163
164	switch (param->test_type) {
165	case syscall_test:
166		topts.ctx_in = &args;
167		topts.ctx_size_in = sizeof(args);
168		/* fallthrough */
169	case syscall_null_ctx_test:
170		break;
171	case tc_test:
172		topts.data_in = &pkt_v4;
173		topts.data_size_in = sizeof(pkt_v4);
174		break;
175		topts.repeat = 1;
176	}
177
178	skel = kfunc_call_fail__open_opts(&opts);
179	if (!ASSERT_OK_PTR(skel, "kfunc_call_fail__open_opts"))
180		goto cleanup;
181
182	prog = bpf_object__find_program_by_name(skel->obj, param->prog_name);
183	if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
184		goto cleanup;
185
186	bpf_program__set_autoload(prog, true);
187
188	err = kfunc_call_fail__load(skel);
189	if (!param->retval) {
190		/* the verifier is supposed to complain and refuses to load */
191		if (!ASSERT_ERR(err, "unexpected load success"))
192			goto out_err;
193
194	} else {
195		/* the program is loaded but must dynamically fail */
196		if (!ASSERT_OK(err, "unexpected load error"))
197			goto out_err;
198
199		prog_fd = bpf_program__fd(prog);
200		err = bpf_prog_test_run_opts(prog_fd, &topts);
201		if (!ASSERT_EQ(err, param->retval, param->prog_name))
202			goto out_err;
203	}
204
205out_err:
206	if (!ASSERT_OK_PTR(strstr(obj_log_buf, param->expected_err_msg), "expected_err_msg")) {
207		fprintf(stderr, "Expected err_msg: %s\n", param->expected_err_msg);
208		fprintf(stderr, "Verifier output: %s\n", obj_log_buf);
209	}
210
211cleanup:
212	kfunc_call_fail__destroy(skel);
213}
214
215static void test_main(void)
216{
217	int i;
218
219	for (i = 0; i < ARRAY_SIZE(kfunc_tests); i++) {
220		if (!test__start_subtest(kfunc_tests[i].prog_name))
221			continue;
222
223		if (!kfunc_tests[i].expected_err_msg)
224			verify_success(&kfunc_tests[i]);
225		else
226			verify_fail(&kfunc_tests[i]);
227	}
228}
229
230static void test_subprog(void)
231{
232	struct kfunc_call_test_subprog *skel;
233	int prog_fd, err;
234	LIBBPF_OPTS(bpf_test_run_opts, topts,
235		.data_in = &pkt_v4,
236		.data_size_in = sizeof(pkt_v4),
237		.repeat = 1,
238	);
239
240	skel = kfunc_call_test_subprog__open_and_load();
241	if (!ASSERT_OK_PTR(skel, "skel"))
242		return;
243
244	prog_fd = bpf_program__fd(skel->progs.kfunc_call_test1);
245	err = bpf_prog_test_run_opts(prog_fd, &topts);
246	ASSERT_OK(err, "bpf_prog_test_run(test1)");
247	ASSERT_EQ(topts.retval, 10, "test1-retval");
248	ASSERT_NEQ(skel->data->active_res, -1, "active_res");
249	ASSERT_EQ(skel->data->sk_state_res, BPF_TCP_CLOSE, "sk_state_res");
250
251	kfunc_call_test_subprog__destroy(skel);
252}
253
254static void test_subprog_lskel(void)
255{
256	struct kfunc_call_test_subprog_lskel *skel;
257	int prog_fd, err;
258	LIBBPF_OPTS(bpf_test_run_opts, topts,
259		.data_in = &pkt_v4,
260		.data_size_in = sizeof(pkt_v4),
261		.repeat = 1,
262	);
263
264	skel = kfunc_call_test_subprog_lskel__open_and_load();
265	if (!ASSERT_OK_PTR(skel, "skel"))
266		return;
267
268	prog_fd = skel->progs.kfunc_call_test1.prog_fd;
269	err = bpf_prog_test_run_opts(prog_fd, &topts);
270	ASSERT_OK(err, "bpf_prog_test_run(test1)");
271	ASSERT_EQ(topts.retval, 10, "test1-retval");
272	ASSERT_NEQ(skel->data->active_res, -1, "active_res");
273	ASSERT_EQ(skel->data->sk_state_res, BPF_TCP_CLOSE, "sk_state_res");
274
275	kfunc_call_test_subprog_lskel__destroy(skel);
276}
277
278static int test_destructive_open_and_load(void)
279{
280	struct kfunc_call_destructive *skel;
281	int err;
282
283	skel = kfunc_call_destructive__open();
284	if (!ASSERT_OK_PTR(skel, "prog_open"))
285		return -1;
286
287	err = kfunc_call_destructive__load(skel);
288
289	kfunc_call_destructive__destroy(skel);
290
291	return err;
292}
293
294static void test_destructive(void)
295{
296	__u64 save_caps = 0;
297
298	ASSERT_OK(test_destructive_open_and_load(), "successful_load");
299
300	if (!ASSERT_OK(cap_disable_effective(1ULL << CAP_SYS_BOOT, &save_caps), "drop_caps"))
301		return;
302
303	ASSERT_EQ(test_destructive_open_and_load(), -13, "no_caps_failure");
304
305	cap_enable_effective(save_caps, NULL);
306}
307
308void test_kfunc_call(void)
309{
310	test_main();
311
312	if (test__start_subtest("subprog"))
313		test_subprog();
314
315	if (test__start_subtest("subprog_lskel"))
316		test_subprog_lskel();
317
318	if (test__start_subtest("destructive"))
319		test_destructive();
320}