bpf: Test for bpf ID

Add test to exercise the bpf_prog/map id generation,
bpf_(prog|map)_get_next_id(), bpf_(prog|map)_get_fd_by_id() and
bpf_get_obj_info_by_fd().

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Martin KaFai Lau 2017-06-05 12:15:53 -07:00 committed by David S. Miller
parent 1e27097690
commit 95b9afd398
6 changed files with 341 additions and 1 deletions

View File

@ -82,6 +82,11 @@ enum bpf_cmd {
BPF_PROG_ATTACH,
BPF_PROG_DETACH,
BPF_PROG_TEST_RUN,
BPF_PROG_GET_NEXT_ID,
BPF_MAP_GET_NEXT_ID,
BPF_PROG_GET_FD_BY_ID,
BPF_MAP_GET_FD_BY_ID,
BPF_OBJ_GET_INFO_BY_FD,
};
enum bpf_map_type {
@ -209,6 +214,21 @@ union bpf_attr {
__u32 repeat;
__u32 duration;
} test;
struct { /* anonymous struct used by BPF_*_GET_*_ID */
union {
__u32 start_id;
__u32 prog_id;
__u32 map_id;
};
__u32 next_id;
};
struct { /* anonymous struct used by BPF_OBJ_GET_INFO_BY_FD */
__u32 bpf_fd;
__u32 info_len;
__aligned_u64 info;
} info;
} __attribute__((aligned(8)));
/* BPF helper function descriptions:
@ -673,4 +693,25 @@ struct xdp_md {
__u32 data_end;
};
#define BPF_TAG_SIZE 8
struct bpf_prog_info {
__u32 type;
__u32 id;
__u8 tag[BPF_TAG_SIZE];
__u32 jited_prog_len;
__u32 xlated_prog_len;
__aligned_u64 jited_prog_insns;
__aligned_u64 xlated_prog_insns;
} __attribute__((aligned(8)));
struct bpf_map_info {
__u32 type;
__u32 id;
__u32 key_size;
__u32 value_size;
__u32 max_entries;
__u32 map_flags;
} __attribute__((aligned(8)));
#endif /* _UAPI__LINUX_BPF_H__ */

View File

@ -257,3 +257,71 @@ int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
*duration = attr.test.duration;
return ret;
}
int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
{
union bpf_attr attr;
int err;
bzero(&attr, sizeof(attr));
attr.start_id = start_id;
err = sys_bpf(BPF_PROG_GET_NEXT_ID, &attr, sizeof(attr));
if (!err)
*next_id = attr.next_id;
return err;
}
int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
{
union bpf_attr attr;
int err;
bzero(&attr, sizeof(attr));
attr.start_id = start_id;
err = sys_bpf(BPF_MAP_GET_NEXT_ID, &attr, sizeof(attr));
if (!err)
*next_id = attr.next_id;
return err;
}
int bpf_prog_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
bzero(&attr, sizeof(attr));
attr.prog_id = id;
return sys_bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr));
}
int bpf_map_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
bzero(&attr, sizeof(attr));
attr.map_id = id;
return sys_bpf(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr));
}
int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len)
{
union bpf_attr attr;
int err;
bzero(&attr, sizeof(attr));
bzero(info, *info_len);
attr.info.bpf_fd = prog_fd;
attr.info.info_len = *info_len;
attr.info.info = ptr_to_u64(info);
err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr));
if (!err)
*info_len = attr.info.info_len;
return err;
}

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@ -54,5 +54,10 @@ int bpf_prog_detach(int attachable_fd, enum bpf_attach_type type);
int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
void *data_out, __u32 *size_out, __u32 *retval,
__u32 *duration);
int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id);
int bpf_map_get_next_id(__u32 start_id, __u32 *next_id);
int bpf_prog_get_fd_by_id(__u32 id);
int bpf_map_get_fd_by_id(__u32 id);
int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len);
#endif

View File

@ -14,7 +14,7 @@ LDLIBS += -lcap -lelf
TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
test_align
TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o
TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o
TEST_PROGS := test_kmod.sh

View File

@ -0,0 +1,35 @@
/* Copyright (c) 2017 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#include <stddef.h>
#include <linux/bpf.h>
#include <linux/pkt_cls.h>
#include "bpf_helpers.h"
/* It is a dumb bpf program such that it must have no
* issue to be loaded since testing the verifier is
* not the focus here.
*/
int _version SEC("version") = 1;
struct bpf_map_def SEC("maps") test_map_id = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(__u32),
.value_size = sizeof(__u64),
.max_entries = 1,
};
SEC("test_prog_id")
int test_prog_id(struct __sk_buff *skb)
{
__u32 key = 0;
__u64 *value;
value = bpf_map_lookup_elem(&test_map_id, &key);
return TC_ACT_OK;
}

View File

@ -22,6 +22,8 @@ typedef __u16 __sum16;
#include <sys/wait.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <pwd.h>
#include <linux/bpf.h>
#include <linux/err.h>
@ -70,6 +72,7 @@ static struct {
pass_cnt++; \
printf("%s:PASS:%s %d nsec\n", __func__, tag, duration);\
} \
__ret; \
})
static int bpf_prog_load(const char *file, enum bpf_prog_type type,
@ -283,6 +286,193 @@ static void test_tcp_estats(void)
bpf_object__close(obj);
}
static inline __u64 ptr_to_u64(const void *ptr)
{
return (__u64) (unsigned long) ptr;
}
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";
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];
char jited_insns[128], xlated_insns[128];
__u32 i, next_id, info_len, nr_id_found, duration = 0;
int err = 0;
__u64 array_value;
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() */
for (i = 0; i < nr_iters; i++) {
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.
*/
assert(!err);
/* Check getting prog info */
info_len = sizeof(struct bpf_prog_info) * 2;
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);
err = bpf_obj_get_info_by_fd(prog_fds[i], &prog_infos[i],
&info_len);
if (CHECK(err ||
prog_infos[i].type != BPF_PROG_TYPE_SOCKET_FILTER ||
info_len != sizeof(struct bpf_prog_info) ||
!prog_infos[i].jited_prog_len ||
!prog_infos[i].xlated_prog_len,
"get-prog-info(fd)",
"err %d errno %d i %d type %d(%d) info_len %u(%lu) jited_prog_len %u xlated_prog_len %u\n",
err, errno, i,
prog_infos[i].type, BPF_PROG_TYPE_SOCKET_FILTER,
info_len, sizeof(struct bpf_prog_info),
prog_infos[i].jited_prog_len,
prog_infos[i].xlated_prog_len))
goto done;
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;
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),
"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\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))
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;
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++;
err = bpf_obj_get_info_by_fd(prog_fd, &prog_info, &info_len);
CHECK(err || info_len != sizeof(struct bpf_prog_info) ||
memcmp(&prog_info, &prog_infos[i], info_len),
"get-prog-info(next_id->fd)",
"err %d errno %d info_len %u(%lu) memcmp %d\n",
err, errno, info_len, sizeof(struct bpf_prog_info),
memcmp(&prog_info, &prog_infos[i], info_len));
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]);
}
int main(void)
{
struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
@ -293,6 +483,7 @@ int main(void)
test_xdp();
test_l4lb();
test_tcp_estats();
test_bpf_obj_id();
printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
return 0;