1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (C) 2021. Huawei Technologies Co., Ltd */
  3#include <test_progs.h>
  4#include "strncmp_test.skel.h"
  5
  6static int trigger_strncmp(const struct strncmp_test *skel)
  7{
  8	int cmp;
  9
 10	usleep(1);
 11
 12	cmp = skel->bss->cmp_ret;
 13	if (cmp > 0)
 14		return 1;
 15	if (cmp < 0)
 16		return -1;
 17	return 0;
 18}
 19
 20/*
 21 * Compare str and target after making str[i] != target[i].
 22 * When exp is -1, make str[i] < target[i] and delta = -1.
 23 */
 24static void strncmp_full_str_cmp(struct strncmp_test *skel, const char *name,
 25				 int exp)
 26{
 27	size_t nr = sizeof(skel->bss->str);
 28	char *str = skel->bss->str;
 29	int delta = exp;
 30	int got;
 31	size_t i;
 32
 33	memcpy(str, skel->rodata->target, nr);
 34	for (i = 0; i < nr - 1; i++) {
 35		str[i] += delta;
 36
 37		got = trigger_strncmp(skel);
 38		ASSERT_EQ(got, exp, name);
 39
 40		str[i] -= delta;
 41	}
 42}
 43
 44static void test_strncmp_ret(void)
 45{
 46	struct strncmp_test *skel;
 47	int err, got;
 48
 49	skel = strncmp_test__open();
 50	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
 51		return;
 52
 53	bpf_program__set_autoload(skel->progs.do_strncmp, true);
 54
 55	err = strncmp_test__load(skel);
 56	if (!ASSERT_EQ(err, 0, "strncmp_test load"))
 57		goto out;
 58
 59	err = strncmp_test__attach(skel);
 60	if (!ASSERT_EQ(err, 0, "strncmp_test attach"))
 61		goto out;
 62
 63	skel->bss->target_pid = getpid();
 64
 65	/* Empty str */
 66	skel->bss->str[0] = '\0';
 67	got = trigger_strncmp(skel);
 68	ASSERT_EQ(got, -1, "strncmp: empty str");
 69
 70	/* Same string */
 71	memcpy(skel->bss->str, skel->rodata->target, sizeof(skel->bss->str));
 72	got = trigger_strncmp(skel);
 73	ASSERT_EQ(got, 0, "strncmp: same str");
 74
 75	/* Not-null-terminated string  */
 76	memcpy(skel->bss->str, skel->rodata->target, sizeof(skel->bss->str));
 77	skel->bss->str[sizeof(skel->bss->str) - 1] = 'A';
 78	got = trigger_strncmp(skel);
 79	ASSERT_EQ(got, 1, "strncmp: not-null-term str");
 80
 81	strncmp_full_str_cmp(skel, "strncmp: less than", -1);
 82	strncmp_full_str_cmp(skel, "strncmp: greater than", 1);
 83out:
 84	strncmp_test__destroy(skel);
 85}
 86
 87static void test_strncmp_bad_not_const_str_size(void)
 88{
 89	struct strncmp_test *skel;
 90	int err;
 91
 92	skel = strncmp_test__open();
 93	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
 94		return;
 95
 96	bpf_program__set_autoload(skel->progs.strncmp_bad_not_const_str_size, true);
 97
 98	err = strncmp_test__load(skel);
 99	ASSERT_ERR(err, "strncmp_test load bad_not_const_str_size");
100
101	strncmp_test__destroy(skel);
102}
103
104static void test_strncmp_bad_writable_target(void)
105{
106	struct strncmp_test *skel;
107	int err;
108
109	skel = strncmp_test__open();
110	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
111		return;
112
113	bpf_program__set_autoload(skel->progs.strncmp_bad_writable_target, true);
114
115	err = strncmp_test__load(skel);
116	ASSERT_ERR(err, "strncmp_test load bad_writable_target");
117
118	strncmp_test__destroy(skel);
119}
120
121static void test_strncmp_bad_not_null_term_target(void)
122{
123	struct strncmp_test *skel;
124	int err;
125
126	skel = strncmp_test__open();
127	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
128		return;
129
130	bpf_program__set_autoload(skel->progs.strncmp_bad_not_null_term_target, true);
131
132	err = strncmp_test__load(skel);
133	ASSERT_ERR(err, "strncmp_test load bad_not_null_term_target");
134
135	strncmp_test__destroy(skel);
136}
137
138void test_test_strncmp(void)
139{
140	if (test__start_subtest("strncmp_ret"))
141		test_strncmp_ret();
142	if (test__start_subtest("strncmp_bad_not_const_str_size"))
143		test_strncmp_bad_not_const_str_size();
144	if (test__start_subtest("strncmp_bad_writable_target"))
145		test_strncmp_bad_writable_target();
146	if (test__start_subtest("strncmp_bad_not_null_term_target"))
147		test_strncmp_bad_not_null_term_target();
148}