mirror of https://gitee.com/openkylin/linux.git
80 lines
2.4 KiB
C
80 lines
2.4 KiB
C
/* SCTP kernel reference Implementation
|
|
* Copyright (c) 1999-2001 Motorola, Inc.
|
|
* Copyright (c) 2001-2003 International Business Machines, Corp.
|
|
*
|
|
* This file is part of the SCTP kernel reference Implementation
|
|
*
|
|
* SCTP Checksum functions
|
|
*
|
|
* The SCTP reference implementation is free software;
|
|
* you can redistribute it and/or modify it under the terms of
|
|
* the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2, or (at your option)
|
|
* any later version.
|
|
*
|
|
* The SCTP reference implementation 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with GNU CC; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, 59 Temple Place - Suite 330,
|
|
* Boston, MA 02111-1307, USA.
|
|
*
|
|
* Please send any bug reports or fixes you make to the
|
|
* email address(es):
|
|
* lksctp developers <linux-sctp@vger.kernel.org>
|
|
*
|
|
* Written or modified by:
|
|
* Dinakaran Joseph
|
|
* Jon Grimm <jgrimm@us.ibm.com>
|
|
* Sridhar Samudrala <sri@us.ibm.com>
|
|
*
|
|
* Rewritten to use libcrc32c by:
|
|
* Vlad Yasevich <vladislav.yasevich@hp.com>
|
|
*/
|
|
|
|
#ifndef __sctp_checksum_h__
|
|
#define __sctp_checksum_h__
|
|
|
|
#include <linux/types.h>
|
|
#include <net/sctp/sctp.h>
|
|
#include <linux/crc32c.h>
|
|
#include <linux/crc32.h>
|
|
|
|
static inline __wsum sctp_csum_update(const void *buff, int len, __wsum sum)
|
|
{
|
|
/* This uses the crypto implementation of crc32c, which is either
|
|
* implemented w/ hardware support or resolves to __crc32c_le().
|
|
*/
|
|
return crc32c(sum, buff, len);
|
|
}
|
|
|
|
static inline __wsum sctp_csum_combine(__wsum csum, __wsum csum2,
|
|
int offset, int len)
|
|
{
|
|
return __crc32c_le_combine(csum, csum2, len);
|
|
}
|
|
|
|
static inline __le32 sctp_compute_cksum(const struct sk_buff *skb,
|
|
unsigned int offset)
|
|
{
|
|
struct sctphdr *sh = sctp_hdr(skb);
|
|
__le32 ret, old = sh->checksum;
|
|
const struct skb_checksum_ops ops = {
|
|
.update = sctp_csum_update,
|
|
.combine = sctp_csum_combine,
|
|
};
|
|
|
|
sh->checksum = 0;
|
|
ret = cpu_to_le32(~__skb_checksum(skb, offset, skb->len - offset,
|
|
~(__u32)0, &ops));
|
|
sh->checksum = old;
|
|
|
|
return ret;
|
|
}
|
|
|
|
#endif /* __sctp_checksum_h__ */
|