int get_map_fd_by_prog_id(int prog_id)
{
struct bpf_prog_info info = {};
__u32 info_len = sizeof(info);
__u32 map_ids[1];
int prog_fd = -1;
int map_fd = -1;
prog_fd = bpf_prog_get_fd_by_id(prog_id);
if (prog_fd < 0) {
log_err("Failed to get fd by prog id %d", prog_id);
goto err;
}
info.nr_map_ids = 1;
info.map_ids = (__u64) (unsigned long) map_ids;
if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) {
log_err("Failed to get info by prog fd %d", prog_fd);
goto err;
}
if (!info.nr_map_ids) {
log_err("No maps found for prog fd %d", prog_fd);
goto err;
}
map_fd = bpf_map_get_fd_by_id(map_ids[0]);
if (map_fd < 0)
log_err("Failed to get fd by map id %d", map_ids[0]);
err:
if (prog_fd >= 0)
close(prog_fd);
return map_fd;
}
static int show_bpf_prog(int id, const char *attach_type_str,
const char *attach_flags_str,
int level)
{
struct bpf_prog_info info = {};
__u32 info_len = sizeof(info);
int prog_fd;
prog_fd = bpf_prog_get_fd_by_id(id);
if (prog_fd < 0)
return -1;
if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) {
close(prog_fd);
return -1;
}
if (json_output) {
jsonw_start_object(json_wtr);
jsonw_uint_field(json_wtr, "id", info.id);
jsonw_string_field(json_wtr, "attach_type",
attach_type_str);
jsonw_string_field(json_wtr, "attach_flags",
attach_flags_str);
jsonw_string_field(json_wtr, "name", info.name);
jsonw_end_object(json_wtr);
} else {
printf("%s%-8u %-15s %-15s %-15s\n", level ? " " : "",
info.id,
attach_type_str,
attach_flags_str,
info.name);
}
close(prog_fd);
return 0;
}
static void test_bpf_obj_id(void)
{
const __u64 array_magic_value = 0xfaceb00c;
const __u32 array_key = 0;
const int nr_iters = 2;
const char *file = "./test_obj_id.o";
const char *jit_sysctl = "/proc/sys/net/core/bpf_jit_enable";
const char *expected_prog_name = "test_obj_id";
const char *expected_map_name = "test_map_id";
const __u64 nsec_per_sec = 1000000000;
struct bpf_object *objs[nr_iters];
int prog_fds[nr_iters], map_fds[nr_iters];
/* +1 to test for the info_len returned by kernel */
struct bpf_prog_info prog_infos[nr_iters + 1];
struct bpf_map_info map_infos[nr_iters + 1];
/* Each prog only uses one map. +1 to test nr_map_ids
* returned by kernel.
*/
__u32 map_ids[nr_iters + 1];
char jited_insns[128], xlated_insns[128], zeros[128];
__u32 i, next_id, info_len, nr_id_found, duration = 0;
struct timespec real_time_ts, boot_time_ts;
int sysctl_fd, jit_enabled = 0, err = 0;
__u64 array_value;
uid_t my_uid = getuid();
time_t now, load_time;
sysctl_fd = open(jit_sysctl, 0, O_RDONLY);
if (sysctl_fd != -1) {
char tmpc;
if (read(sysctl_fd, &tmpc, sizeof(tmpc)) == 1)
jit_enabled = (tmpc != '0');
close(sysctl_fd);
}
err = bpf_prog_get_fd_by_id(0);
CHECK(err >= 0 || errno != ENOENT,
"get-fd-by-notexist-prog-id", "err %d errno %d\n", err, errno);
err = bpf_map_get_fd_by_id(0);
CHECK(err >= 0 || errno != ENOENT,
"get-fd-by-notexist-map-id", "err %d errno %d\n", err, errno);
for (i = 0; i < nr_iters; i++)
objs[i] = NULL;
/* Check bpf_obj_get_info_by_fd() */
bzero(zeros, sizeof(zeros));
for (i = 0; i < nr_iters; i++) {
now = time(NULL);
err = bpf_prog_load(file, BPF_PROG_TYPE_SOCKET_FILTER,
&objs[i], &prog_fds[i]);
/* test_obj_id.o is a dumb prog. It should never fail
* to load.
*/
if (err)
error_cnt++;
assert(!err);
/* Insert a magic value to the map */
map_fds[i] = bpf_find_map(__func__, objs[i], "test_map_id");
assert(map_fds[i] >= 0);
err = bpf_map_update_elem(map_fds[i], &array_key,
&array_magic_value, 0);
assert(!err);
/* Check getting map info */
info_len = sizeof(struct bpf_map_info) * 2;
bzero(&map_infos[i], info_len);
err = bpf_obj_get_info_by_fd(map_fds[i], &map_infos[i],
&info_len);
if (CHECK(err ||
map_infos[i].type != BPF_MAP_TYPE_ARRAY ||
map_infos[i].key_size != sizeof(__u32) ||
map_infos[i].value_size != sizeof(__u64) ||
map_infos[i].max_entries != 1 ||
map_infos[i].map_flags != 0 ||
info_len != sizeof(struct bpf_map_info) ||
strcmp((char *)map_infos[i].name, expected_map_name),
"get-map-info(fd)",
"err %d errno %d type %d(%d) info_len %u(%lu) key_size %u value_size %u max_entries %u map_flags %X name %s(%s)\n",
err, errno,
map_infos[i].type, BPF_MAP_TYPE_ARRAY,
info_len, sizeof(struct bpf_map_info),
map_infos[i].key_size,
map_infos[i].value_size,
map_infos[i].max_entries,
map_infos[i].map_flags,
map_infos[i].name, expected_map_name))
goto done;
/* Check getting prog info */
info_len = sizeof(struct bpf_prog_info) * 2;
bzero(&prog_infos[i], info_len);
bzero(jited_insns, sizeof(jited_insns));
bzero(xlated_insns, sizeof(xlated_insns));
prog_infos[i].jited_prog_insns = ptr_to_u64(jited_insns);
prog_infos[i].jited_prog_len = sizeof(jited_insns);
prog_infos[i].xlated_prog_insns = ptr_to_u64(xlated_insns);
prog_infos[i].xlated_prog_len = sizeof(xlated_insns);
prog_infos[i].map_ids = ptr_to_u64(map_ids + i);
prog_infos[i].nr_map_ids = 2;
err = clock_gettime(CLOCK_REALTIME, &real_time_ts);
assert(!err);
err = clock_gettime(CLOCK_BOOTTIME, &boot_time_ts);
assert(!err);
err = bpf_obj_get_info_by_fd(prog_fds[i], &prog_infos[i],
&info_len);
load_time = (real_time_ts.tv_sec - boot_time_ts.tv_sec)
+ (prog_infos[i].load_time / nsec_per_sec);
if (CHECK(err ||
prog_infos[i].type != BPF_PROG_TYPE_SOCKET_FILTER ||
info_len != sizeof(struct bpf_prog_info) ||
(jit_enabled && !prog_infos[i].jited_prog_len) ||
(jit_enabled &&
!memcmp(jited_insns, zeros, sizeof(zeros))) ||
!prog_infos[i].xlated_prog_len ||
!memcmp(xlated_insns, zeros, sizeof(zeros)) ||
load_time < now - 60 || load_time > now + 60 ||
prog_infos[i].created_by_uid != my_uid ||
prog_infos[i].nr_map_ids != 1 ||
*(int *)prog_infos[i].map_ids != map_infos[i].id ||
strcmp((char *)prog_infos[i].name, expected_prog_name),
"get-prog-info(fd)",
"err %d errno %d i %d type %d(%d) info_len %u(%lu) jit_enabled %d jited_prog_len %u xlated_prog_len %u jited_prog %d xlated_prog %d load_time %lu(%lu) uid %u(%u) nr_map_ids %u(%u) map_id %u(%u) name %s(%s)\n",
err, errno, i,
prog_infos[i].type, BPF_PROG_TYPE_SOCKET_FILTER,
info_len, sizeof(struct bpf_prog_info),
jit_enabled,
prog_infos[i].jited_prog_len,
prog_infos[i].xlated_prog_len,
!!memcmp(jited_insns, zeros, sizeof(zeros)),
!!memcmp(xlated_insns, zeros, sizeof(zeros)),
load_time, now,
prog_infos[i].created_by_uid, my_uid,
prog_infos[i].nr_map_ids, 1,
*(int *)prog_infos[i].map_ids, map_infos[i].id,
prog_infos[i].name, expected_prog_name))
goto done;
}
/* Check bpf_prog_get_next_id() */
nr_id_found = 0;
next_id = 0;
while (!bpf_prog_get_next_id(next_id, &next_id)) {
struct bpf_prog_info prog_info = {};
__u32 saved_map_id;
int prog_fd;
info_len = sizeof(prog_info);
prog_fd = bpf_prog_get_fd_by_id(next_id);
if (prog_fd < 0 && errno == ENOENT)
/* The bpf_prog is in the dead row */
continue;
if (CHECK(prog_fd < 0, "get-prog-fd(next_id)",
"prog_fd %d next_id %d errno %d\n",
prog_fd, next_id, errno))
break;
for (i = 0; i < nr_iters; i++)
if (prog_infos[i].id == next_id)
break;
if (i == nr_iters)
continue;
nr_id_found++;
/* Negative test:
* prog_info.nr_map_ids = 1
* prog_info.map_ids = NULL
*/
prog_info.nr_map_ids = 1;
err = bpf_obj_get_info_by_fd(prog_fd, &prog_info, &info_len);
if (CHECK(!err || errno != EFAULT,
"get-prog-fd-bad-nr-map-ids", "err %d errno %d(%d)",
err, errno, EFAULT))
break;
bzero(&prog_info, sizeof(prog_info));
info_len = sizeof(prog_info);
saved_map_id = *(int *)(prog_infos[i].map_ids);
prog_info.map_ids = prog_infos[i].map_ids;
prog_info.nr_map_ids = 2;
err = bpf_obj_get_info_by_fd(prog_fd, &prog_info, &info_len);
prog_infos[i].jited_prog_insns = 0;
prog_infos[i].xlated_prog_insns = 0;
CHECK(err || info_len != sizeof(struct bpf_prog_info) ||
memcmp(&prog_info, &prog_infos[i], info_len) ||
*(int *)prog_info.map_ids != saved_map_id,
"get-prog-info(next_id->fd)",
"err %d errno %d info_len %u(%lu) memcmp %d map_id %u(%u)\n",
err, errno, info_len, sizeof(struct bpf_prog_info),
memcmp(&prog_info, &prog_infos[i], info_len),
*(int *)prog_info.map_ids, saved_map_id);
close(prog_fd);
}
CHECK(nr_id_found != nr_iters,
"check total prog id found by get_next_id",
"nr_id_found %u(%u)\n",
nr_id_found, nr_iters);
/* Check bpf_map_get_next_id() */
nr_id_found = 0;
next_id = 0;
while (!bpf_map_get_next_id(next_id, &next_id)) {
struct bpf_map_info map_info = {};
int map_fd;
info_len = sizeof(map_info);
map_fd = bpf_map_get_fd_by_id(next_id);
if (map_fd < 0 && errno == ENOENT)
/* The bpf_map is in the dead row */
continue;
if (CHECK(map_fd < 0, "get-map-fd(next_id)",
"map_fd %d next_id %u errno %d\n",
map_fd, next_id, errno))
break;
for (i = 0; i < nr_iters; i++)
if (map_infos[i].id == next_id)
break;
if (i == nr_iters)
continue;
nr_id_found++;
err = bpf_map_lookup_elem(map_fd, &array_key, &array_value);
assert(!err);
err = bpf_obj_get_info_by_fd(map_fd, &map_info, &info_len);
CHECK(err || info_len != sizeof(struct bpf_map_info) ||
memcmp(&map_info, &map_infos[i], info_len) ||
array_value != array_magic_value,
"check get-map-info(next_id->fd)",
"err %d errno %d info_len %u(%lu) memcmp %d array_value %llu(%llu)\n",
err, errno, info_len, sizeof(struct bpf_map_info),
memcmp(&map_info, &map_infos[i], info_len),
array_value, array_magic_value);
close(map_fd);
}
CHECK(nr_id_found != nr_iters,
"check total map id found by get_next_id",
"nr_id_found %u(%u)\n",
nr_id_found, nr_iters);
done:
for (i = 0; i < nr_iters; i++)
bpf_object__close(objs[i]);
}
