// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020 Google LLC.
*/
#include <test_progs.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <unistd.h>
#include <malloc.h>
#include <stdlib.h>
#include "lsm.skel.h"
#include "lsm_tailcall.skel.h"
char *CMD_ARGS[] = {"true", NULL};
#define GET_PAGE_ADDR(ADDR, PAGE_SIZE) \
(char *)(((unsigned long) (ADDR + PAGE_SIZE)) & ~(PAGE_SIZE-1))
int stack_mprotect(void)
{
void *buf;
long sz;
int ret;
sz = sysconf(_SC_PAGESIZE);
if (sz < 0)
return sz;
buf = alloca(sz * 3);
ret = mprotect(GET_PAGE_ADDR(buf, sz), sz,
PROT_READ | PROT_WRITE | PROT_EXEC);
return ret;
}
int exec_cmd(int *monitored_pid)
{
int child_pid, child_status;
child_pid = fork();
if (child_pid == 0) {
*monitored_pid = getpid();
execvp(CMD_ARGS[0], CMD_ARGS);
return -EINVAL;
} else if (child_pid > 0) {
waitpid(child_pid, &child_status, 0);
return child_status;
}
return -EINVAL;
}
static int test_lsm(struct lsm *skel)
{
struct bpf_link *link;
int buf = 1234;
int err;
err = lsm__attach(skel);
if (!ASSERT_OK(err, "attach"))
return err;
/* Check that already linked program can't be attached again. */
link = bpf_program__attach(skel->progs.test_int_hook);
if (!ASSERT_ERR_PTR(link, "attach_link"))
return -1;
err = exec_cmd(&skel->bss->monitored_pid);
if (!ASSERT_OK(err, "exec_cmd"))
return err;
ASSERT_EQ(skel->bss->bprm_count, 1, "bprm_count");
skel->bss->monitored_pid = getpid();
err = stack_mprotect();
if (!ASSERT_EQ(err, -1, "stack_mprotect") ||
!ASSERT_EQ(errno, EPERM, "stack_mprotect"))
return err;
ASSERT_EQ(skel->bss->mprotect_count, 1, "mprotect_count");
syscall(__NR_setdomainname, &buf, -2L);
syscall(__NR_setdomainname, 0, -3L);
syscall(__NR_setdomainname, ~0L, -4L);
ASSERT_EQ(skel->bss->copy_test, 3, "copy_test");
lsm__detach(skel);
skel->bss->copy_test = 0;
skel->bss->bprm_count = 0;
skel->bss->mprotect_count = 0;
return 0;
}
static void test_lsm_basic(void)
{
struct lsm *skel = NULL;
int err;
skel = lsm__open_and_load();
if (!ASSERT_OK_PTR(skel, "lsm_skel_load"))
goto close_prog;
err = test_lsm(skel);
if (!ASSERT_OK(err, "test_lsm_first_attach"))
goto close_prog;
err = test_lsm(skel);
ASSERT_OK(err, "test_lsm_second_attach");
close_prog:
lsm__destroy(skel);
}
static void test_lsm_tailcall(void)
{
struct lsm_tailcall *skel = NULL;
int map_fd, prog_fd;
int err, key;
skel = lsm_tailcall__open_and_load();
if (!ASSERT_OK_PTR(skel, "lsm_tailcall__skel_load"))
goto close_prog;
map_fd = bpf_map__fd(skel->maps.jmp_table);
if (CHECK_FAIL(map_fd < 0))
goto close_prog;
prog_fd = bpf_program__fd(skel->progs.lsm_file_permission_prog);
if (CHECK_FAIL(prog_fd < 0))
goto close_prog;
key = 0;
err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY);
if (CHECK_FAIL(!err))
goto close_prog;
prog_fd = bpf_program__fd(skel->progs.lsm_file_alloc_security_prog);
if (CHECK_FAIL(prog_fd < 0))
goto close_prog;
err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY);
if (CHECK_FAIL(err))
goto close_prog;
close_prog:
lsm_tailcall__destroy(skel);
}
void test_test_lsm(void)
{
if (test__start_subtest("lsm_basic"))
test_lsm_basic();
if (test__start_subtest("lsm_tailcall"))
test_lsm_tailcall();
}