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mirror of https://github.com/edk2-porting/linux-next.git synced 2025-01-06 20:53:54 +08:00
linux-next/tools/lib/bpf/bpf.c
Andrii Nakryiko d10ef2b825 libbpf: Unify low-level BPF_PROG_LOAD APIs into bpf_prog_load()
Add a new unified OPTS-based low-level API for program loading,
bpf_prog_load() ([0]).  bpf_prog_load() accepts few "mandatory"
parameters as input arguments (program type, name, license,
instructions) and all the other optional (as in not required to specify
for all types of BPF programs) fields into struct bpf_prog_load_opts.

This makes all the other non-extensible APIs variant for BPF_PROG_LOAD
obsolete and they are slated for deprecation in libbpf v0.7:
  - bpf_load_program();
  - bpf_load_program_xattr();
  - bpf_verify_program().

Implementation-wise, internal helper libbpf__bpf_prog_load is refactored
to become a public bpf_prog_load() API. struct bpf_prog_load_params used
internally is replaced by public struct bpf_prog_load_opts.

Unfortunately, while conceptually all this is pretty straightforward,
the biggest complication comes from the already existing bpf_prog_load()
*high-level* API, which has nothing to do with BPF_PROG_LOAD command.

We try really hard to have a new API named bpf_prog_load(), though,
because it maps naturally to BPF_PROG_LOAD command.

For that, we rename old bpf_prog_load() into bpf_prog_load_deprecated()
and mark it as COMPAT_VERSION() for shared library users compiled
against old version of libbpf. Statically linked users and shared lib
users compiled against new version of libbpf headers will get "rerouted"
to bpf_prog_deprecated() through a macro helper that decides whether to
use new or old bpf_prog_load() based on number of input arguments (see
___libbpf_overload in libbpf_common.h).

To test that existing
bpf_prog_load()-using code compiles and works as expected, I've compiled
and ran selftests as is. I had to remove (locally) selftest/bpf/Makefile
-Dbpf_prog_load=bpf_prog_test_load hack because it was conflicting with
the macro-based overload approach. I don't expect anyone else to do
something like this in practice, though. This is testing-specific way to
replace bpf_prog_load() calls with special testing variant of it, which
adds extra prog_flags value. After testing I kept this selftests hack,
but ensured that we use a new bpf_prog_load_deprecated name for this.

This patch also marks bpf_prog_load() and bpf_prog_load_xattr() as deprecated.
bpf_object interface has to be used for working with struct bpf_program.
Libbpf doesn't support loading just a bpf_program.

The silver lining is that when we get to libbpf 1.0 all these
complication will be gone and we'll have one clean bpf_prog_load()
low-level API with no backwards compatibility hackery surrounding it.

  [0] Closes: https://github.com/libbpf/libbpf/issues/284

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211103220845.2676888-4-andrii@kernel.org
2021-11-07 08:34:23 -08:00

1138 lines
29 KiB
C

// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/*
* common eBPF ELF operations.
*
* Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
* Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
* Copyright (C) 2015 Huawei Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License (not later!)
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see <http://www.gnu.org/licenses>
*/
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <unistd.h>
#include <asm/unistd.h>
#include <errno.h>
#include <linux/bpf.h>
#include <limits.h>
#include "bpf.h"
#include "libbpf.h"
#include "libbpf_internal.h"
/*
* When building perf, unistd.h is overridden. __NR_bpf is
* required to be defined explicitly.
*/
#ifndef __NR_bpf
# if defined(__i386__)
# define __NR_bpf 357
# elif defined(__x86_64__)
# define __NR_bpf 321
# elif defined(__aarch64__)
# define __NR_bpf 280
# elif defined(__sparc__)
# define __NR_bpf 349
# elif defined(__s390__)
# define __NR_bpf 351
# elif defined(__arc__)
# define __NR_bpf 280
# else
# error __NR_bpf not defined. libbpf does not support your arch.
# endif
#endif
static inline __u64 ptr_to_u64(const void *ptr)
{
return (__u64) (unsigned long) ptr;
}
static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
unsigned int size)
{
return syscall(__NR_bpf, cmd, attr, size);
}
static inline int sys_bpf_fd(enum bpf_cmd cmd, union bpf_attr *attr,
unsigned int size)
{
int fd;
fd = sys_bpf(cmd, attr, size);
return ensure_good_fd(fd);
}
#define PROG_LOAD_ATTEMPTS 5
static inline int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts)
{
int fd;
do {
fd = sys_bpf_fd(BPF_PROG_LOAD, attr, size);
} while (fd < 0 && errno == EAGAIN && --attempts > 0);
return fd;
}
int libbpf__bpf_create_map_xattr(const struct bpf_create_map_params *create_attr)
{
union bpf_attr attr;
int fd;
memset(&attr, '\0', sizeof(attr));
attr.map_type = create_attr->map_type;
attr.key_size = create_attr->key_size;
attr.value_size = create_attr->value_size;
attr.max_entries = create_attr->max_entries;
attr.map_flags = create_attr->map_flags;
if (create_attr->name)
memcpy(attr.map_name, create_attr->name,
min(strlen(create_attr->name), BPF_OBJ_NAME_LEN - 1));
attr.numa_node = create_attr->numa_node;
attr.btf_fd = create_attr->btf_fd;
attr.btf_key_type_id = create_attr->btf_key_type_id;
attr.btf_value_type_id = create_attr->btf_value_type_id;
attr.map_ifindex = create_attr->map_ifindex;
if (attr.map_type == BPF_MAP_TYPE_STRUCT_OPS)
attr.btf_vmlinux_value_type_id =
create_attr->btf_vmlinux_value_type_id;
else
attr.inner_map_fd = create_attr->inner_map_fd;
attr.map_extra = create_attr->map_extra;
fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr)
{
struct bpf_create_map_params p = {};
p.map_type = create_attr->map_type;
p.key_size = create_attr->key_size;
p.value_size = create_attr->value_size;
p.max_entries = create_attr->max_entries;
p.map_flags = create_attr->map_flags;
p.name = create_attr->name;
p.numa_node = create_attr->numa_node;
p.btf_fd = create_attr->btf_fd;
p.btf_key_type_id = create_attr->btf_key_type_id;
p.btf_value_type_id = create_attr->btf_value_type_id;
p.map_ifindex = create_attr->map_ifindex;
if (p.map_type == BPF_MAP_TYPE_STRUCT_OPS)
p.btf_vmlinux_value_type_id =
create_attr->btf_vmlinux_value_type_id;
else
p.inner_map_fd = create_attr->inner_map_fd;
return libbpf__bpf_create_map_xattr(&p);
}
int bpf_create_map_node(enum bpf_map_type map_type, const char *name,
int key_size, int value_size, int max_entries,
__u32 map_flags, int node)
{
struct bpf_create_map_attr map_attr = {};
map_attr.name = name;
map_attr.map_type = map_type;
map_attr.map_flags = map_flags;
map_attr.key_size = key_size;
map_attr.value_size = value_size;
map_attr.max_entries = max_entries;
if (node >= 0) {
map_attr.numa_node = node;
map_attr.map_flags |= BPF_F_NUMA_NODE;
}
return bpf_create_map_xattr(&map_attr);
}
int bpf_create_map(enum bpf_map_type map_type, int key_size,
int value_size, int max_entries, __u32 map_flags)
{
struct bpf_create_map_attr map_attr = {};
map_attr.map_type = map_type;
map_attr.map_flags = map_flags;
map_attr.key_size = key_size;
map_attr.value_size = value_size;
map_attr.max_entries = max_entries;
return bpf_create_map_xattr(&map_attr);
}
int bpf_create_map_name(enum bpf_map_type map_type, const char *name,
int key_size, int value_size, int max_entries,
__u32 map_flags)
{
struct bpf_create_map_attr map_attr = {};
map_attr.name = name;
map_attr.map_type = map_type;
map_attr.map_flags = map_flags;
map_attr.key_size = key_size;
map_attr.value_size = value_size;
map_attr.max_entries = max_entries;
return bpf_create_map_xattr(&map_attr);
}
int bpf_create_map_in_map_node(enum bpf_map_type map_type, const char *name,
int key_size, int inner_map_fd, int max_entries,
__u32 map_flags, int node)
{
union bpf_attr attr;
int fd;
memset(&attr, '\0', sizeof(attr));
attr.map_type = map_type;
attr.key_size = key_size;
attr.value_size = 4;
attr.inner_map_fd = inner_map_fd;
attr.max_entries = max_entries;
attr.map_flags = map_flags;
if (name)
memcpy(attr.map_name, name,
min(strlen(name), BPF_OBJ_NAME_LEN - 1));
if (node >= 0) {
attr.map_flags |= BPF_F_NUMA_NODE;
attr.numa_node = node;
}
fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_create_map_in_map(enum bpf_map_type map_type, const char *name,
int key_size, int inner_map_fd, int max_entries,
__u32 map_flags)
{
return bpf_create_map_in_map_node(map_type, name, key_size,
inner_map_fd, max_entries, map_flags,
-1);
}
static void *
alloc_zero_tailing_info(const void *orecord, __u32 cnt,
__u32 actual_rec_size, __u32 expected_rec_size)
{
__u64 info_len = (__u64)actual_rec_size * cnt;
void *info, *nrecord;
int i;
info = malloc(info_len);
if (!info)
return NULL;
/* zero out bytes kernel does not understand */
nrecord = info;
for (i = 0; i < cnt; i++) {
memcpy(nrecord, orecord, expected_rec_size);
memset(nrecord + expected_rec_size, 0,
actual_rec_size - expected_rec_size);
orecord += actual_rec_size;
nrecord += actual_rec_size;
}
return info;
}
DEFAULT_VERSION(bpf_prog_load_v0_6_0, bpf_prog_load, LIBBPF_0.6.0)
int bpf_prog_load_v0_6_0(enum bpf_prog_type prog_type,
const char *prog_name, const char *license,
const struct bpf_insn *insns, size_t insn_cnt,
const struct bpf_prog_load_opts *opts)
{
void *finfo = NULL, *linfo = NULL;
const char *func_info, *line_info;
__u32 log_size, log_level, attach_prog_fd, attach_btf_obj_fd;
__u32 func_info_rec_size, line_info_rec_size;
int fd, attempts;
union bpf_attr attr;
char *log_buf;
if (!OPTS_VALID(opts, bpf_prog_load_opts))
return libbpf_err(-EINVAL);
attempts = OPTS_GET(opts, attempts, 0);
if (attempts < 0)
return libbpf_err(-EINVAL);
if (attempts == 0)
attempts = PROG_LOAD_ATTEMPTS;
memset(&attr, 0, sizeof(attr));
attr.prog_type = prog_type;
attr.expected_attach_type = OPTS_GET(opts, expected_attach_type, 0);
attr.prog_btf_fd = OPTS_GET(opts, prog_btf_fd, 0);
attr.prog_flags = OPTS_GET(opts, prog_flags, 0);
attr.prog_ifindex = OPTS_GET(opts, prog_ifindex, 0);
attr.kern_version = OPTS_GET(opts, kern_version, 0);
if (prog_name)
strncat(attr.prog_name, prog_name, sizeof(attr.prog_name) - 1);
attr.license = ptr_to_u64(license);
if (insn_cnt > UINT_MAX)
return libbpf_err(-E2BIG);
attr.insns = ptr_to_u64(insns);
attr.insn_cnt = (__u32)insn_cnt;
attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0);
attach_btf_obj_fd = OPTS_GET(opts, attach_btf_obj_fd, 0);
if (attach_prog_fd && attach_btf_obj_fd)
return libbpf_err(-EINVAL);
attr.attach_btf_id = OPTS_GET(opts, attach_btf_id, 0);
if (attach_prog_fd)
attr.attach_prog_fd = attach_prog_fd;
else
attr.attach_btf_obj_fd = attach_btf_obj_fd;
log_buf = OPTS_GET(opts, log_buf, NULL);
log_size = OPTS_GET(opts, log_size, 0);
log_level = OPTS_GET(opts, log_level, 0);
if (!!log_buf != !!log_size)
return libbpf_err(-EINVAL);
if (log_level > (4 | 2 | 1))
return libbpf_err(-EINVAL);
if (log_level && !log_buf)
return libbpf_err(-EINVAL);
attr.log_level = log_level;
attr.log_buf = ptr_to_u64(log_buf);
attr.log_size = log_size;
func_info_rec_size = OPTS_GET(opts, func_info_rec_size, 0);
func_info = OPTS_GET(opts, func_info, NULL);
attr.func_info_rec_size = func_info_rec_size;
attr.func_info = ptr_to_u64(func_info);
attr.func_info_cnt = OPTS_GET(opts, func_info_cnt, 0);
line_info_rec_size = OPTS_GET(opts, line_info_rec_size, 0);
line_info = OPTS_GET(opts, line_info, NULL);
attr.line_info_rec_size = line_info_rec_size;
attr.line_info = ptr_to_u64(line_info);
attr.line_info_cnt = OPTS_GET(opts, line_info_cnt, 0);
attr.fd_array = ptr_to_u64(OPTS_GET(opts, fd_array, NULL));
fd = sys_bpf_prog_load(&attr, sizeof(attr), attempts);
if (fd >= 0)
return fd;
/* After bpf_prog_load, the kernel may modify certain attributes
* to give user space a hint how to deal with loading failure.
* Check to see whether we can make some changes and load again.
*/
while (errno == E2BIG && (!finfo || !linfo)) {
if (!finfo && attr.func_info_cnt &&
attr.func_info_rec_size < func_info_rec_size) {
/* try with corrected func info records */
finfo = alloc_zero_tailing_info(func_info,
attr.func_info_cnt,
func_info_rec_size,
attr.func_info_rec_size);
if (!finfo) {
errno = E2BIG;
goto done;
}
attr.func_info = ptr_to_u64(finfo);
attr.func_info_rec_size = func_info_rec_size;
} else if (!linfo && attr.line_info_cnt &&
attr.line_info_rec_size < line_info_rec_size) {
linfo = alloc_zero_tailing_info(line_info,
attr.line_info_cnt,
line_info_rec_size,
attr.line_info_rec_size);
if (!linfo) {
errno = E2BIG;
goto done;
}
attr.line_info = ptr_to_u64(linfo);
attr.line_info_rec_size = line_info_rec_size;
} else {
break;
}
fd = sys_bpf_prog_load(&attr, sizeof(attr), attempts);
if (fd >= 0)
goto done;
}
if (log_level || !log_buf)
goto done;
/* Try again with log */
log_buf[0] = 0;
attr.log_buf = ptr_to_u64(log_buf);
attr.log_size = log_size;
attr.log_level = 1;
fd = sys_bpf_prog_load(&attr, sizeof(attr), attempts);
done:
/* free() doesn't affect errno, so we don't need to restore it */
free(finfo);
free(linfo);
return libbpf_err_errno(fd);
}
int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
char *log_buf, size_t log_buf_sz)
{
LIBBPF_OPTS(bpf_prog_load_opts, p);
if (!load_attr || !log_buf != !log_buf_sz)
return libbpf_err(-EINVAL);
p.expected_attach_type = load_attr->expected_attach_type;
switch (load_attr->prog_type) {
case BPF_PROG_TYPE_STRUCT_OPS:
case BPF_PROG_TYPE_LSM:
p.attach_btf_id = load_attr->attach_btf_id;
break;
case BPF_PROG_TYPE_TRACING:
case BPF_PROG_TYPE_EXT:
p.attach_btf_id = load_attr->attach_btf_id;
p.attach_prog_fd = load_attr->attach_prog_fd;
break;
default:
p.prog_ifindex = load_attr->prog_ifindex;
p.kern_version = load_attr->kern_version;
}
p.log_level = load_attr->log_level;
p.log_buf = log_buf;
p.log_size = log_buf_sz;
p.prog_btf_fd = load_attr->prog_btf_fd;
p.func_info_rec_size = load_attr->func_info_rec_size;
p.func_info_cnt = load_attr->func_info_cnt;
p.func_info = load_attr->func_info;
p.line_info_rec_size = load_attr->line_info_rec_size;
p.line_info_cnt = load_attr->line_info_cnt;
p.line_info = load_attr->line_info;
p.prog_flags = load_attr->prog_flags;
return bpf_prog_load(load_attr->prog_type, load_attr->name, load_attr->license,
load_attr->insns, load_attr->insns_cnt, &p);
}
int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, const char *license,
__u32 kern_version, char *log_buf,
size_t log_buf_sz)
{
struct bpf_load_program_attr load_attr;
memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
load_attr.prog_type = type;
load_attr.expected_attach_type = 0;
load_attr.name = NULL;
load_attr.insns = insns;
load_attr.insns_cnt = insns_cnt;
load_attr.license = license;
load_attr.kern_version = kern_version;
return bpf_load_program_xattr(&load_attr, log_buf, log_buf_sz);
}
int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, __u32 prog_flags, const char *license,
__u32 kern_version, char *log_buf, size_t log_buf_sz,
int log_level)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.prog_type = type;
attr.insn_cnt = (__u32)insns_cnt;
attr.insns = ptr_to_u64(insns);
attr.license = ptr_to_u64(license);
attr.log_buf = ptr_to_u64(log_buf);
attr.log_size = log_buf_sz;
attr.log_level = log_level;
log_buf[0] = 0;
attr.kern_version = kern_version;
attr.prog_flags = prog_flags;
fd = sys_bpf_prog_load(&attr, sizeof(attr), PROG_LOAD_ATTEMPTS);
return libbpf_err_errno(fd);
}
int bpf_map_update_elem(int fd, const void *key, const void *value,
__u64 flags)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
attr.value = ptr_to_u64(value);
attr.flags = flags;
ret = sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_map_lookup_elem(int fd, const void *key, void *value)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
attr.value = ptr_to_u64(value);
ret = sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
attr.value = ptr_to_u64(value);
attr.flags = flags;
ret = sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
attr.value = ptr_to_u64(value);
ret = sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_map_lookup_and_delete_elem_flags(int fd, const void *key, void *value, __u64 flags)
{
union bpf_attr attr;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
attr.value = ptr_to_u64(value);
attr.flags = flags;
return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
}
int bpf_map_delete_elem(int fd, const void *key)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
ret = sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_map_get_next_key(int fd, const void *key, void *next_key)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
attr.key = ptr_to_u64(key);
attr.next_key = ptr_to_u64(next_key);
ret = sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_map_freeze(int fd)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.map_fd = fd;
ret = sys_bpf(BPF_MAP_FREEZE, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
static int bpf_map_batch_common(int cmd, int fd, void *in_batch,
void *out_batch, void *keys, void *values,
__u32 *count,
const struct bpf_map_batch_opts *opts)
{
union bpf_attr attr;
int ret;
if (!OPTS_VALID(opts, bpf_map_batch_opts))
return libbpf_err(-EINVAL);
memset(&attr, 0, sizeof(attr));
attr.batch.map_fd = fd;
attr.batch.in_batch = ptr_to_u64(in_batch);
attr.batch.out_batch = ptr_to_u64(out_batch);
attr.batch.keys = ptr_to_u64(keys);
attr.batch.values = ptr_to_u64(values);
attr.batch.count = *count;
attr.batch.elem_flags = OPTS_GET(opts, elem_flags, 0);
attr.batch.flags = OPTS_GET(opts, flags, 0);
ret = sys_bpf(cmd, &attr, sizeof(attr));
*count = attr.batch.count;
return libbpf_err_errno(ret);
}
int bpf_map_delete_batch(int fd, void *keys, __u32 *count,
const struct bpf_map_batch_opts *opts)
{
return bpf_map_batch_common(BPF_MAP_DELETE_BATCH, fd, NULL,
NULL, keys, NULL, count, opts);
}
int bpf_map_lookup_batch(int fd, void *in_batch, void *out_batch, void *keys,
void *values, __u32 *count,
const struct bpf_map_batch_opts *opts)
{
return bpf_map_batch_common(BPF_MAP_LOOKUP_BATCH, fd, in_batch,
out_batch, keys, values, count, opts);
}
int bpf_map_lookup_and_delete_batch(int fd, void *in_batch, void *out_batch,
void *keys, void *values, __u32 *count,
const struct bpf_map_batch_opts *opts)
{
return bpf_map_batch_common(BPF_MAP_LOOKUP_AND_DELETE_BATCH,
fd, in_batch, out_batch, keys, values,
count, opts);
}
int bpf_map_update_batch(int fd, void *keys, void *values, __u32 *count,
const struct bpf_map_batch_opts *opts)
{
return bpf_map_batch_common(BPF_MAP_UPDATE_BATCH, fd, NULL, NULL,
keys, values, count, opts);
}
int bpf_obj_pin(int fd, const char *pathname)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.pathname = ptr_to_u64((void *)pathname);
attr.bpf_fd = fd;
ret = sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_obj_get(const char *pathname)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.pathname = ptr_to_u64((void *)pathname);
fd = sys_bpf_fd(BPF_OBJ_GET, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
unsigned int flags)
{
DECLARE_LIBBPF_OPTS(bpf_prog_attach_opts, opts,
.flags = flags,
);
return bpf_prog_attach_xattr(prog_fd, target_fd, type, &opts);
}
int bpf_prog_attach_xattr(int prog_fd, int target_fd,
enum bpf_attach_type type,
const struct bpf_prog_attach_opts *opts)
{
union bpf_attr attr;
int ret;
if (!OPTS_VALID(opts, bpf_prog_attach_opts))
return libbpf_err(-EINVAL);
memset(&attr, 0, sizeof(attr));
attr.target_fd = target_fd;
attr.attach_bpf_fd = prog_fd;
attr.attach_type = type;
attr.attach_flags = OPTS_GET(opts, flags, 0);
attr.replace_bpf_fd = OPTS_GET(opts, replace_prog_fd, 0);
ret = sys_bpf(BPF_PROG_ATTACH, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.target_fd = target_fd;
attr.attach_type = type;
ret = sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.target_fd = target_fd;
attr.attach_bpf_fd = prog_fd;
attr.attach_type = type;
ret = sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_link_create(int prog_fd, int target_fd,
enum bpf_attach_type attach_type,
const struct bpf_link_create_opts *opts)
{
__u32 target_btf_id, iter_info_len;
union bpf_attr attr;
int fd;
if (!OPTS_VALID(opts, bpf_link_create_opts))
return libbpf_err(-EINVAL);
iter_info_len = OPTS_GET(opts, iter_info_len, 0);
target_btf_id = OPTS_GET(opts, target_btf_id, 0);
/* validate we don't have unexpected combinations of non-zero fields */
if (iter_info_len || target_btf_id) {
if (iter_info_len && target_btf_id)
return libbpf_err(-EINVAL);
if (!OPTS_ZEROED(opts, target_btf_id))
return libbpf_err(-EINVAL);
}
memset(&attr, 0, sizeof(attr));
attr.link_create.prog_fd = prog_fd;
attr.link_create.target_fd = target_fd;
attr.link_create.attach_type = attach_type;
attr.link_create.flags = OPTS_GET(opts, flags, 0);
if (target_btf_id) {
attr.link_create.target_btf_id = target_btf_id;
goto proceed;
}
switch (attach_type) {
case BPF_TRACE_ITER:
attr.link_create.iter_info = ptr_to_u64(OPTS_GET(opts, iter_info, (void *)0));
attr.link_create.iter_info_len = iter_info_len;
break;
case BPF_PERF_EVENT:
attr.link_create.perf_event.bpf_cookie = OPTS_GET(opts, perf_event.bpf_cookie, 0);
if (!OPTS_ZEROED(opts, perf_event))
return libbpf_err(-EINVAL);
break;
default:
if (!OPTS_ZEROED(opts, flags))
return libbpf_err(-EINVAL);
break;
}
proceed:
fd = sys_bpf_fd(BPF_LINK_CREATE, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_link_detach(int link_fd)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.link_detach.link_fd = link_fd;
ret = sys_bpf(BPF_LINK_DETACH, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_link_update(int link_fd, int new_prog_fd,
const struct bpf_link_update_opts *opts)
{
union bpf_attr attr;
int ret;
if (!OPTS_VALID(opts, bpf_link_update_opts))
return libbpf_err(-EINVAL);
memset(&attr, 0, sizeof(attr));
attr.link_update.link_fd = link_fd;
attr.link_update.new_prog_fd = new_prog_fd;
attr.link_update.flags = OPTS_GET(opts, flags, 0);
attr.link_update.old_prog_fd = OPTS_GET(opts, old_prog_fd, 0);
ret = sys_bpf(BPF_LINK_UPDATE, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}
int bpf_iter_create(int link_fd)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.iter_create.link_fd = link_fd;
fd = sys_bpf_fd(BPF_ITER_CREATE, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,
__u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.query.target_fd = target_fd;
attr.query.attach_type = type;
attr.query.query_flags = query_flags;
attr.query.prog_cnt = *prog_cnt;
attr.query.prog_ids = ptr_to_u64(prog_ids);
ret = sys_bpf(BPF_PROG_QUERY, &attr, sizeof(attr));
if (attach_flags)
*attach_flags = attr.query.attach_flags;
*prog_cnt = attr.query.prog_cnt;
return libbpf_err_errno(ret);
}
int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
void *data_out, __u32 *size_out, __u32 *retval,
__u32 *duration)
{
union bpf_attr attr;
int ret;
memset(&attr, 0, sizeof(attr));
attr.test.prog_fd = prog_fd;
attr.test.data_in = ptr_to_u64(data);
attr.test.data_out = ptr_to_u64(data_out);
attr.test.data_size_in = size;
attr.test.repeat = repeat;
ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
if (size_out)
*size_out = attr.test.data_size_out;
if (retval)
*retval = attr.test.retval;
if (duration)
*duration = attr.test.duration;
return libbpf_err_errno(ret);
}
int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
{
union bpf_attr attr;
int ret;
if (!test_attr->data_out && test_attr->data_size_out > 0)
return libbpf_err(-EINVAL);
memset(&attr, 0, sizeof(attr));
attr.test.prog_fd = test_attr->prog_fd;
attr.test.data_in = ptr_to_u64(test_attr->data_in);
attr.test.data_out = ptr_to_u64(test_attr->data_out);
attr.test.data_size_in = test_attr->data_size_in;
attr.test.data_size_out = test_attr->data_size_out;
attr.test.ctx_in = ptr_to_u64(test_attr->ctx_in);
attr.test.ctx_out = ptr_to_u64(test_attr->ctx_out);
attr.test.ctx_size_in = test_attr->ctx_size_in;
attr.test.ctx_size_out = test_attr->ctx_size_out;
attr.test.repeat = test_attr->repeat;
ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
test_attr->data_size_out = attr.test.data_size_out;
test_attr->ctx_size_out = attr.test.ctx_size_out;
test_attr->retval = attr.test.retval;
test_attr->duration = attr.test.duration;
return libbpf_err_errno(ret);
}
int bpf_prog_test_run_opts(int prog_fd, struct bpf_test_run_opts *opts)
{
union bpf_attr attr;
int ret;
if (!OPTS_VALID(opts, bpf_test_run_opts))
return libbpf_err(-EINVAL);
memset(&attr, 0, sizeof(attr));
attr.test.prog_fd = prog_fd;
attr.test.cpu = OPTS_GET(opts, cpu, 0);
attr.test.flags = OPTS_GET(opts, flags, 0);
attr.test.repeat = OPTS_GET(opts, repeat, 0);
attr.test.duration = OPTS_GET(opts, duration, 0);
attr.test.ctx_size_in = OPTS_GET(opts, ctx_size_in, 0);
attr.test.ctx_size_out = OPTS_GET(opts, ctx_size_out, 0);
attr.test.data_size_in = OPTS_GET(opts, data_size_in, 0);
attr.test.data_size_out = OPTS_GET(opts, data_size_out, 0);
attr.test.ctx_in = ptr_to_u64(OPTS_GET(opts, ctx_in, NULL));
attr.test.ctx_out = ptr_to_u64(OPTS_GET(opts, ctx_out, NULL));
attr.test.data_in = ptr_to_u64(OPTS_GET(opts, data_in, NULL));
attr.test.data_out = ptr_to_u64(OPTS_GET(opts, data_out, NULL));
ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
OPTS_SET(opts, data_size_out, attr.test.data_size_out);
OPTS_SET(opts, ctx_size_out, attr.test.ctx_size_out);
OPTS_SET(opts, duration, attr.test.duration);
OPTS_SET(opts, retval, attr.test.retval);
return libbpf_err_errno(ret);
}
static int bpf_obj_get_next_id(__u32 start_id, __u32 *next_id, int cmd)
{
union bpf_attr attr;
int err;
memset(&attr, 0, sizeof(attr));
attr.start_id = start_id;
err = sys_bpf(cmd, &attr, sizeof(attr));
if (!err)
*next_id = attr.next_id;
return libbpf_err_errno(err);
}
int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
{
return bpf_obj_get_next_id(start_id, next_id, BPF_PROG_GET_NEXT_ID);
}
int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
{
return bpf_obj_get_next_id(start_id, next_id, BPF_MAP_GET_NEXT_ID);
}
int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id)
{
return bpf_obj_get_next_id(start_id, next_id, BPF_BTF_GET_NEXT_ID);
}
int bpf_link_get_next_id(__u32 start_id, __u32 *next_id)
{
return bpf_obj_get_next_id(start_id, next_id, BPF_LINK_GET_NEXT_ID);
}
int bpf_prog_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.prog_id = id;
fd = sys_bpf_fd(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_map_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.map_id = id;
fd = sys_bpf_fd(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_btf_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.btf_id = id;
fd = sys_bpf_fd(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_link_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.link_id = id;
fd = sys_bpf_fd(BPF_LINK_GET_FD_BY_ID, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len)
{
union bpf_attr attr;
int err;
memset(&attr, 0, sizeof(attr));
attr.info.bpf_fd = bpf_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 libbpf_err_errno(err);
}
int bpf_raw_tracepoint_open(const char *name, int prog_fd)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.raw_tracepoint.name = ptr_to_u64(name);
attr.raw_tracepoint.prog_fd = prog_fd;
fd = sys_bpf_fd(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_load_btf(const void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size,
bool do_log)
{
union bpf_attr attr = {};
int fd;
attr.btf = ptr_to_u64(btf);
attr.btf_size = btf_size;
retry:
if (do_log && log_buf && log_buf_size) {
attr.btf_log_level = 1;
attr.btf_log_size = log_buf_size;
attr.btf_log_buf = ptr_to_u64(log_buf);
}
fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, sizeof(attr));
if (fd < 0 && !do_log && log_buf && log_buf_size) {
do_log = true;
goto retry;
}
return libbpf_err_errno(fd);
}
int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len,
__u32 *prog_id, __u32 *fd_type, __u64 *probe_offset,
__u64 *probe_addr)
{
union bpf_attr attr = {};
int err;
attr.task_fd_query.pid = pid;
attr.task_fd_query.fd = fd;
attr.task_fd_query.flags = flags;
attr.task_fd_query.buf = ptr_to_u64(buf);
attr.task_fd_query.buf_len = *buf_len;
err = sys_bpf(BPF_TASK_FD_QUERY, &attr, sizeof(attr));
*buf_len = attr.task_fd_query.buf_len;
*prog_id = attr.task_fd_query.prog_id;
*fd_type = attr.task_fd_query.fd_type;
*probe_offset = attr.task_fd_query.probe_offset;
*probe_addr = attr.task_fd_query.probe_addr;
return libbpf_err_errno(err);
}
int bpf_enable_stats(enum bpf_stats_type type)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.enable_stats.type = type;
fd = sys_bpf_fd(BPF_ENABLE_STATS, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
int bpf_prog_bind_map(int prog_fd, int map_fd,
const struct bpf_prog_bind_opts *opts)
{
union bpf_attr attr;
int ret;
if (!OPTS_VALID(opts, bpf_prog_bind_opts))
return libbpf_err(-EINVAL);
memset(&attr, 0, sizeof(attr));
attr.prog_bind_map.prog_fd = prog_fd;
attr.prog_bind_map.map_fd = map_fd;
attr.prog_bind_map.flags = OPTS_GET(opts, flags, 0);
ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, sizeof(attr));
return libbpf_err_errno(ret);
}