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// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2025 Google LLC. */
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <test_progs.h>
#include <bpf/btf.h>
#include "map_excl.skel.h"
#include "bpf_iter_bpf_array_map.skel.h"
#ifndef SHA256_DIGEST_SIZE
#define SHA256_DIGEST_SIZE 32
#endif
static void test_map_excl_allowed(void)
{
struct map_excl *skel = map_excl__open();
int err;
err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
if (!ASSERT_OK(err, "bpf_map__set_exclusive_program"))
goto out;
bpf_program__set_autoload(skel->progs.should_have_access, true);
bpf_program__set_autoload(skel->progs.should_not_have_access, false);
err = map_excl__load(skel);
ASSERT_OK(err, "map_excl__load");
out:
map_excl__destroy(skel);
}
static void test_map_excl_denied(void)
{
struct map_excl *skel = map_excl__open();
int err;
err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
if (!ASSERT_OK(err, "bpf_map__make_exclusive"))
goto out;
bpf_program__set_autoload(skel->progs.should_have_access, false);
bpf_program__set_autoload(skel->progs.should_not_have_access, true);
err = map_excl__load(skel);
ASSERT_EQ(err, -EACCES, "exclusive map access not denied\n");
out:
map_excl__destroy(skel);
}
static void test_map_excl_no_map_in_map(void)
{
__u8 hash[SHA256_DIGEST_SIZE] = {};
LIBBPF_OPTS(bpf_map_create_opts, excl_opts,
.excl_prog_hash = hash,
.excl_prog_hash_size = sizeof(hash));
LIBBPF_OPTS(bpf_map_create_opts, outer_opts);
int excl_fd, tmpl_fd = -1, outer_fd = -1, err;
__u32 key = 0;
excl_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl_inner", 4, 4, 1, &excl_opts);
if (!ASSERT_OK_FD(excl_fd, "create exclusive map"))
return;
outer_opts.inner_map_fd = excl_fd;
err = bpf_map_create(BPF_MAP_TYPE_ARRAY_OF_MAPS, "outer_from_excl",
4, 4, 1, &outer_opts);
if (err >= 0)
close(err);
ASSERT_EQ(err, -ENOTSUPP, "reject exclusive map as map-in-map template");
tmpl_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "tmpl", 4, 4, 1, NULL);
if (!ASSERT_OK_FD(tmpl_fd, "create inner template"))
goto out;
outer_opts.inner_map_fd = tmpl_fd;
outer_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY_OF_MAPS, "outer", 4, 4, 1, &outer_opts);
if (!ASSERT_OK_FD(outer_fd, "create map-of-maps"))
goto out;
err = bpf_map_update_elem(outer_fd, &key, &excl_fd, 0);
ASSERT_EQ(err, -ENOTSUPP, "reject exclusive map as map-in-map element");
out:
if (outer_fd >= 0)
close(outer_fd);
if (tmpl_fd >= 0)
close(tmpl_fd);
close(excl_fd);
}
static void test_map_excl_no_map_iter(void)
{
__u8 hash[SHA256_DIGEST_SIZE] = {};
LIBBPF_OPTS(bpf_map_create_opts, excl_opts,
.excl_prog_hash = hash,
.excl_prog_hash_size = sizeof(hash));
DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
struct bpf_iter_bpf_array_map *skel = NULL;
union bpf_iter_link_info linfo;
struct bpf_link *link;
int excl_fd;
excl_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl_iter", 4, 8, 3, &excl_opts);
if (!ASSERT_OK_FD(excl_fd, "create exclusive map"))
return;
skel = bpf_iter_bpf_array_map__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_array_map__open_and_load"))
goto out;
memset(&linfo, 0, sizeof(linfo));
linfo.map.map_fd = excl_fd;
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
link = bpf_program__attach_iter(skel->progs.dump_bpf_array_map, &opts);
if (!ASSERT_ERR_PTR(link, "reject exclusive map as iter target")) {
bpf_link__destroy(link);
goto out;
}
ASSERT_EQ(libbpf_get_error(link), -EPERM, "iter attach errno");
out:
bpf_iter_bpf_array_map__destroy(skel);
close(excl_fd);
}
static void test_map_excl_create_validation(void)
{
LIBBPF_OPTS(bpf_map_create_opts, o);
__u8 hash[SHA256_DIGEST_SIZE] = {};
int fd;
o.excl_prog_hash = hash;
o.excl_prog_hash_size = SHA256_DIGEST_SIZE / 2;
fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl", 4, 4, 1, &o);
if (fd >= 0)
close(fd);
ASSERT_EQ(fd, -EINVAL, "reject short excl_prog_hash_size");
o.excl_prog_hash = hash;
o.excl_prog_hash_size = SHA256_DIGEST_SIZE * 2;
fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl", 4, 4, 1, &o);
if (fd >= 0)
close(fd);
ASSERT_EQ(fd, -EINVAL, "reject long excl_prog_hash_size");
o.excl_prog_hash = hash;
o.excl_prog_hash_size = 0;
fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl", 4, 4, 1, &o);
if (fd >= 0)
close(fd);
ASSERT_EQ(fd, -EINVAL, "reject hash pointer with zero size");
o.excl_prog_hash = NULL;
o.excl_prog_hash_size = SHA256_DIGEST_SIZE;
fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl", 4, 4, 1, &o);
if (fd >= 0)
close(fd);
ASSERT_EQ(fd, -EINVAL, "reject size with NULL hash pointer");
}
/*
* The exclusive map bound through a continuous fd_array rather than by an
* insn. The kernel resolves the array before it verifies the program, so it
* has to have the digest of the program at hand by then.
*/
static void test_map_excl_fd_array(void)
{
struct map_excl *skel = map_excl__open();
LIBBPF_OPTS(bpf_prog_load_opts, opts);
int err, fd, map_fd;
if (!ASSERT_OK_PTR(skel, "map_excl__open"))
return;
err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
if (!ASSERT_OK(err, "bpf_map__set_exclusive_program"))
goto out;
bpf_program__set_autoload(skel->progs.should_have_access, true);
bpf_program__set_autoload(skel->progs.should_not_have_access, true);
err = bpf_object__prepare(skel->obj);
if (!ASSERT_OK(err, "map_excl prepare"))
goto out;
map_fd = bpf_map__fd(skel->maps.excl_map);
opts.fd_array = &map_fd;
opts.fd_array_cnt = 1;
fd = bpf_program__clone(skel->progs.should_have_access, &opts);
if (ASSERT_GE(fd, 0, "exclusive program with the map in fd_array"))
close(fd);
fd = bpf_program__clone(skel->progs.should_not_have_access, &opts);
ASSERT_EQ(fd, -EACCES, "other program with the map in fd_array");
out:
map_excl__destroy(skel);
}
void test_map_excl(void)
{
if (test__start_subtest("map_excl_allowed"))
test_map_excl_allowed();
if (test__start_subtest("map_excl_denied"))
test_map_excl_denied();
if (test__start_subtest("map_excl_fd_array"))
test_map_excl_fd_array();
if (test__start_subtest("map_excl_no_map_in_map"))
test_map_excl_no_map_in_map();
if (test__start_subtest("map_excl_no_map_iter"))
test_map_excl_no_map_iter();
if (test__start_subtest("map_excl_create_validation"))
test_map_excl_create_validation();
}
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