/* SPDX-License-Identifier: GPL-2.0-or-later
* Copyright 2023 Red Hat GmbH
* Author: Alice Frosi <afrosi@redhat.com>
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <check.h>
#include "cooker/filter.h"
#include "disasm.h"
#include "testutil.h"
char tfilter[] = "/tmp/test-filter.bpf";
static bool filter_eq(struct sock_filter *f1, struct sock_filter *f2,
unsigned int n)
{
unsigned i;
for (i = 0; i < n; i++) {
if (memcmp((void *)(f1 + i), (void *)(f2 + i),
sizeof(struct sock_filter)) != 0) {
printf("expected:\n");
bpf_disasm(f1[i], i);
printf("got:\n");
bpf_disasm(f2[i], i);
return false;
}
}
return true;
}
START_TEST(test_single_instr)
{
struct sock_filter result[10];
unsigned int size;
long nr = 42;
struct sock_filter expected[] = {
/* l0 */ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, arch))),
/* l1 */
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, SEITAN_AUDIT_ARCH, 1, 0),
/* l10 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l2 */
BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, nr))),
/* l3 */ EQ(nr, 1, 0),
/* l4 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l5 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
};
filter_notify(nr);
filter_flush_args(nr);
filter_write(tfilter);
size = read_filter(result, tfilter);
bpf_disasm_all(result, size);
ck_assert(filter_eq(expected, result, ARRAY_SIZE(expected)));
}
END_TEST
START_TEST(test_single_instr_two_args)
{
unsigned int size;
long nr = 42;
struct bpf_field a1 = {
.arg = 1, .cmp = EQ, .value = { .v32 = 0x123 }, .type = BPF_U32
};
struct bpf_field a2 = {
.arg = 2, .cmp = EQ, .value = { .v32 = 0x321 }, .type = BPF_U32
};
struct sock_filter result[20];
struct sock_filter expected[] = {
/* l0 */ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, arch))),
/* l1 */
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, SEITAN_AUDIT_ARCH, 1, 0),
/* l2 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l3 */
BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, nr))),
/* l4 */ EQ(nr, 2, 0),
/* l5 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l6 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l7 */ LOAD(offsetof(struct seccomp_data, args[1])),
/* l8 */ EQ(0x123, 0, 3),
/* l9 */ LOAD(offsetof(struct seccomp_data, args[2])),
/* l10 */ EQ(0x321, 0, 1),
/* l11 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l12 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
};
filter_notify(nr);
filter_add_check(&a1);
filter_add_check(&a2);
filter_flush_args(nr);
filter_write(tfilter);
size = read_filter(result, tfilter);
bpf_disasm_all(result, size);
ck_assert(filter_eq(expected, result, ARRAY_SIZE(expected)));
}
END_TEST
START_TEST(test_two_instr)
{
unsigned int size;
struct sock_filter expected[] = {
/* l0 */ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, arch))),
/* l1 */
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, SEITAN_AUDIT_ARCH, 1, 0),
/* l2 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l3 */
BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, nr))),
/* ------- level0 -------- */
/* l4 */ JGE(49, 1, 0),
/* ------- leaves -------- */
/* l5 */ EQ(42, 2, 1),
/* l6 */ EQ(49, 1, 0),
/* l7 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l8 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
};
struct sock_filter result[30];
filter_notify(42);
filter_flush_args(42);
filter_notify(49);
filter_flush_args(49);
filter_write(tfilter);
size = read_filter(result, tfilter);
bpf_disasm_all(result, size);
ck_assert(filter_eq(expected, result, ARRAY_SIZE(expected)));
}
END_TEST
START_TEST(test_multiple_instr_no_args)
{
unsigned long nrs[] = { 42, 43, 44, 45, 46 };
unsigned int size;
struct sock_filter expected[] = {
/* l0 */ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, arch))),
/* l1 */
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, SEITAN_AUDIT_ARCH, 1, 0),
/* l2 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l3 */
BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, nr))),
/* ------- level0 -------- */
/* l4 */ JGE(46, 1, 0),
/* ------- level1 -------- */
/* l5 */ JGE(45, 2, 1),
/* l6 */ JGE(46, 3, 2),
/* ------- level2 -------- */
/* l7 */ JGE(43, 4, 3),
/* l8 */ JGE(45, 5, 4),
/* l9 */ JGE(46, 6, 5),
/* l10 */ JUMPA(5),
/* -------- leaves ------- */
/* l11 */ EQ(42, 5, 4),
/* l12 */ EQ(43, 4, 3),
/* l13 */ EQ(44, 3, 2),
/* l14 */ EQ(45, 2, 1),
/* l15 */ EQ(46, 1, 0),
/* l16 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l17 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
};
struct sock_filter result[sizeof(expected) / sizeof(expected[0]) + 10];
for(unsigned int i = 0; i < ARRAY_SIZE(nrs); i++) {
filter_notify(nrs[i]);
filter_flush_args(nrs[i]);
}
filter_write(tfilter);
size = read_filter(result, tfilter);
bpf_disasm_all(result, size);
ck_assert(filter_eq(expected, result, ARRAY_SIZE(expected)));
}
END_TEST
START_TEST(test_multiple_instr_with_args)
{
unsigned int size;
struct bpf_field a1 = {
.arg = 1, .cmp = EQ, .value = { .v32 = 0x123 }, .type = BPF_U32
};
struct bpf_field a2 = {
.arg = 2, .cmp = EQ, .value = { .v32 = 0x321 }, .type = BPF_U32
};
struct sock_filter expected[] = {
/* l0 */ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, arch))),
/* l1 */
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, SEITAN_AUDIT_ARCH, 1, 0),
/* l2 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l3 */
BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, nr))),
/* ------- level0 -------- */
/* l4 */ JGE(46, 1, 0),
/* ------- level1 -------- */
/* l5 */ JGE(45, 2, 1),
/* l6 */ JGE(46, 3, 2),
/* ------- level2 -------- */
/* l7 */ JGE(43, 4, 3),
/* l8 */ JGE(45, 5, 4),
/* l9 */ JGE(46, 6, 5),
/* l10 */ JUMPA(5),
/* -------- leaves ------- */
/* l11 */ EQ(42, 6, 4),
/* l12 */ EQ(43, 4, 3),
/* l13 */ EQ(44, 3, 2),
/* l14 */ EQ(45, 9, 1),
/* l15 */ EQ(46, 1, 0),
/* l16 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l17 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* ------- args ---------- */
/* l18 */ LOAD(offsetof(struct seccomp_data, args[1])),
/* l19 */ EQ(0x123, 0, 3),
/* l20 */ LOAD(offsetof(struct seccomp_data, args[2])),
/* l21 */ EQ(0x321, 0, 1),
/* l22 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l23 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* ----- end call42 ------ */
/* l24 */ LOAD(offsetof(struct seccomp_data, args[1])),
/* l25 */ EQ(0x123, 0, 3),
/* l26 */ LOAD(offsetof(struct seccomp_data, args[2])),
/* l27 */ EQ(0x321, 0, 1),
/* l28 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l29 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* ----- end call45 ------ */
};
struct sock_filter result[sizeof(expected) / sizeof(expected[0]) + 10];
filter_notify(42);
filter_add_check(&a1);
filter_add_check(&a2);
filter_flush_args(42);
filter_notify(43);
filter_notify(44);
filter_notify(45);
filter_add_check(&a1);
filter_add_check(&a2);
filter_flush_args(45);
filter_notify(46);
filter_write(tfilter);
size = read_filter(result, tfilter);
bpf_disasm_all(result, size);
ck_assert(filter_eq(expected, result, ARRAY_SIZE(expected)));
}
END_TEST
START_TEST(test_multiple_instance_same_instr)
{
unsigned int size;
struct bpf_field a1 = {
.arg = 1, .cmp = EQ, .value = { .v32 = 0x123 }, .type = BPF_U32
};
struct bpf_field a2 = {
.arg = 2, .cmp = EQ, .value = { .v32 = 0x321 }, .type = BPF_U32
};
struct sock_filter expected[] = {
/* l0 */ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, arch))),
/* l1 */
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, SEITAN_AUDIT_ARCH, 1, 0),
/* l2 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l3 */
BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
(offsetof(struct seccomp_data, nr))),
/* ------- level0 -------- */
/* l4 */ JGE(46, 1, 0),
/* ------- level1 -------- */
/* l5 */ JGE(45, 2, 1),
/* l6 */ JGE(46, 3, 2),
/* ------- level2 -------- */
/* l7 */ JGE(43, 4, 3),
/* l8 */ JGE(45, 5, 4),
/* l9 */ JGE(46, 6, 5),
/* l10 */ JUMPA(5),
/* -------- leaves ------- */
/* l11 */ EQ(42, 6, 4),
/* l12 */ EQ(43, 4, 3),
/* l13 */ EQ(44, 3, 2),
/* l14 */ EQ(45, 10, 1),
/* l15 */ EQ(46, 1, 0),
/* l16 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* l17 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* ------- args ---------- */
/* l18 */ LOAD(offsetof(struct seccomp_data, args[1])),
/* l19 */ EQ(0x123, 0, 1),
/* l20 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l21 */ LOAD(offsetof(struct seccomp_data, args[2])),
/* l22 */ EQ(0x321, 0, 1),
/* l24 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l23 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* ----- end call42 ------ */
/* l25 */ LOAD(offsetof(struct seccomp_data, args[1])),
/* l26 */ EQ(0x123, 0, 1),
/* l24 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l28 */ LOAD(offsetof(struct seccomp_data, args[2])),
/* l29 */ EQ(0x321, 0, 1),
/* l31 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_USER_NOTIF),
/* l30 */ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
/* ----- end call45 ------ */
};
struct sock_filter result[sizeof(expected) / sizeof(expected[0]) + 10];
filter_notify(42);
filter_add_check(&a1);
filter_flush_args(42);
filter_notify(42);
filter_add_check(&a2);
filter_flush_args(42);
filter_notify(43);
filter_notify(44);
filter_notify(45);
filter_add_check(&a1);
filter_flush_args(45);
filter_notify(45);
filter_add_check(&a2);
filter_flush_args(45);
filter_notify(46);
filter_write(tfilter);
size = read_filter(result, tfilter);
bpf_disasm_all(result, size);
ck_assert(filter_eq(expected, result, ARRAY_SIZE(expected)));
}
END_TEST
Suite *bpf_suite(void)
{
Suite *s;
TCase *tsingle_instr, *tmultiple_instr;
s = suite_create("Create BPF filter");
tsingle_instr = tcase_create("single instruction");
tmultiple_instr = tcase_create("multiple instructions");
tcase_add_test(tsingle_instr, test_single_instr);
tcase_add_test(tsingle_instr, test_single_instr_two_args);
tcase_add_test(tmultiple_instr, test_two_instr);
tcase_add_test(tmultiple_instr, test_multiple_instr_no_args);
tcase_add_test(tmultiple_instr, test_multiple_instr_with_args);
tcase_add_test(tmultiple_instr, test_multiple_instance_same_instr);
suite_add_tcase(s, tsingle_instr);
suite_add_tcase(s, tmultiple_instr);
return s;
}
int main(void)
{
int no_failed = 0;
Suite *s;
SRunner *runner;
s = bpf_suite();
runner = srunner_create(s);
srunner_run_all(runner, CK_VERBOSE);
no_failed = srunner_ntests_failed(runner);
srunner_free(runner);
return (no_failed == 0) ? EXIT_SUCCESS : EXIT_FAILURE;
}