mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 02:30:34 +02:00
ee62a5c6bb
Netlink helpers I added in 8bbb77b7c7 ("libbpf: Add various netlink
helpers") used char * casts everywhere, and there were a few more that
existed from before.
Convert all of them to void * cast, as it is treated equivalently by
clang/gcc for the purposes of pointer arithmetic and to follow the
convention elsewhere in the kernel/libbpf.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210619041454.417577-2-memxor@gmail.com
164 lines
3.9 KiB
C
164 lines
3.9 KiB
C
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
|
|
|
|
/*
|
|
* NETLINK Netlink attributes
|
|
*
|
|
* Copyright (c) 2003-2013 Thomas Graf <tgraf@suug.ch>
|
|
*/
|
|
|
|
#ifndef __LIBBPF_NLATTR_H
|
|
#define __LIBBPF_NLATTR_H
|
|
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
#include <linux/netlink.h>
|
|
#include <linux/rtnetlink.h>
|
|
|
|
/* avoid multiple definition of netlink features */
|
|
#define __LINUX_NETLINK_H
|
|
|
|
/**
|
|
* Standard attribute types to specify validation policy
|
|
*/
|
|
enum {
|
|
LIBBPF_NLA_UNSPEC, /**< Unspecified type, binary data chunk */
|
|
LIBBPF_NLA_U8, /**< 8 bit integer */
|
|
LIBBPF_NLA_U16, /**< 16 bit integer */
|
|
LIBBPF_NLA_U32, /**< 32 bit integer */
|
|
LIBBPF_NLA_U64, /**< 64 bit integer */
|
|
LIBBPF_NLA_STRING, /**< NUL terminated character string */
|
|
LIBBPF_NLA_FLAG, /**< Flag */
|
|
LIBBPF_NLA_MSECS, /**< Micro seconds (64bit) */
|
|
LIBBPF_NLA_NESTED, /**< Nested attributes */
|
|
__LIBBPF_NLA_TYPE_MAX,
|
|
};
|
|
|
|
#define LIBBPF_NLA_TYPE_MAX (__LIBBPF_NLA_TYPE_MAX - 1)
|
|
|
|
/**
|
|
* @ingroup attr
|
|
* Attribute validation policy.
|
|
*
|
|
* See section @core_doc{core_attr_parse,Attribute Parsing} for more details.
|
|
*/
|
|
struct libbpf_nla_policy {
|
|
/** Type of attribute or LIBBPF_NLA_UNSPEC */
|
|
uint16_t type;
|
|
|
|
/** Minimal length of payload required */
|
|
uint16_t minlen;
|
|
|
|
/** Maximal length of payload allowed */
|
|
uint16_t maxlen;
|
|
};
|
|
|
|
struct libbpf_nla_req {
|
|
struct nlmsghdr nh;
|
|
union {
|
|
struct ifinfomsg ifinfo;
|
|
struct tcmsg tc;
|
|
};
|
|
char buf[128];
|
|
};
|
|
|
|
/**
|
|
* @ingroup attr
|
|
* Iterate over a stream of attributes
|
|
* @arg pos loop counter, set to current attribute
|
|
* @arg head head of attribute stream
|
|
* @arg len length of attribute stream
|
|
* @arg rem initialized to len, holds bytes currently remaining in stream
|
|
*/
|
|
#define libbpf_nla_for_each_attr(pos, head, len, rem) \
|
|
for (pos = head, rem = len; \
|
|
nla_ok(pos, rem); \
|
|
pos = nla_next(pos, &(rem)))
|
|
|
|
/**
|
|
* libbpf_nla_data - head of payload
|
|
* @nla: netlink attribute
|
|
*/
|
|
static inline void *libbpf_nla_data(const struct nlattr *nla)
|
|
{
|
|
return (void *)nla + NLA_HDRLEN;
|
|
}
|
|
|
|
static inline uint8_t libbpf_nla_getattr_u8(const struct nlattr *nla)
|
|
{
|
|
return *(uint8_t *)libbpf_nla_data(nla);
|
|
}
|
|
|
|
static inline uint32_t libbpf_nla_getattr_u32(const struct nlattr *nla)
|
|
{
|
|
return *(uint32_t *)libbpf_nla_data(nla);
|
|
}
|
|
|
|
static inline const char *libbpf_nla_getattr_str(const struct nlattr *nla)
|
|
{
|
|
return (const char *)libbpf_nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* libbpf_nla_len - length of payload
|
|
* @nla: netlink attribute
|
|
*/
|
|
static inline int libbpf_nla_len(const struct nlattr *nla)
|
|
{
|
|
return nla->nla_len - NLA_HDRLEN;
|
|
}
|
|
|
|
int libbpf_nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head,
|
|
int len, struct libbpf_nla_policy *policy);
|
|
int libbpf_nla_parse_nested(struct nlattr *tb[], int maxtype,
|
|
struct nlattr *nla,
|
|
struct libbpf_nla_policy *policy);
|
|
|
|
int libbpf_nla_dump_errormsg(struct nlmsghdr *nlh);
|
|
|
|
static inline struct nlattr *nla_data(struct nlattr *nla)
|
|
{
|
|
return (struct nlattr *)((void *)nla + NLA_HDRLEN);
|
|
}
|
|
|
|
static inline struct nlattr *req_tail(struct libbpf_nla_req *req)
|
|
{
|
|
return (struct nlattr *)((void *)req + NLMSG_ALIGN(req->nh.nlmsg_len));
|
|
}
|
|
|
|
static inline int nlattr_add(struct libbpf_nla_req *req, int type,
|
|
const void *data, int len)
|
|
{
|
|
struct nlattr *nla;
|
|
|
|
if (NLMSG_ALIGN(req->nh.nlmsg_len) + NLA_ALIGN(NLA_HDRLEN + len) > sizeof(*req))
|
|
return -EMSGSIZE;
|
|
if (!!data != !!len)
|
|
return -EINVAL;
|
|
|
|
nla = req_tail(req);
|
|
nla->nla_type = type;
|
|
nla->nla_len = NLA_HDRLEN + len;
|
|
if (data)
|
|
memcpy(nla_data(nla), data, len);
|
|
req->nh.nlmsg_len = NLMSG_ALIGN(req->nh.nlmsg_len) + NLA_ALIGN(nla->nla_len);
|
|
return 0;
|
|
}
|
|
|
|
static inline struct nlattr *nlattr_begin_nested(struct libbpf_nla_req *req, int type)
|
|
{
|
|
struct nlattr *tail;
|
|
|
|
tail = req_tail(req);
|
|
if (nlattr_add(req, type | NLA_F_NESTED, NULL, 0))
|
|
return NULL;
|
|
return tail;
|
|
}
|
|
|
|
static inline void nlattr_end_nested(struct libbpf_nla_req *req,
|
|
struct nlattr *tail)
|
|
{
|
|
tail->nla_len = (void *)req_tail(req) - (void *)tail;
|
|
}
|
|
|
|
#endif /* __LIBBPF_NLATTR_H */
|