79 lines
2.4 KiB
C
79 lines
2.4 KiB
C
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/* SCTP kernel reference Implementation
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* Copyright (c) 1999-2001 Motorola, Inc.
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* Copyright (c) 2001-2003 International Business Machines, Corp.
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*
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* This file is part of the SCTP kernel reference Implementation
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*
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* SCTP Checksum functions
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*
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* The SCTP reference implementation is free software;
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* you can redistribute it and/or modify it under the terms of
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* the GNU General Public License as published by
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* the Free Software Foundation; either version 2, or (at your option)
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* any later version.
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*
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* The SCTP reference implementation is distributed in the hope that it
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* will be useful, but WITHOUT ANY WARRANTY; without even the implied
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* ************************
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* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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* See the GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with GNU CC; see the file COPYING. If not, write to
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* the Free Software Foundation, 59 Temple Place - Suite 330,
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* Boston, MA 02111-1307, USA.
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*
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* Please send any bug reports or fixes you make to the
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* email address(es):
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* lksctp developers <lksctp-developers@lists.sourceforge.net>
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*
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* Or submit a bug report through the following website:
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* http://www.sf.net/projects/lksctp
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*
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* Written or modified by:
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* Dinakaran Joseph
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* Jon Grimm <jgrimm@us.ibm.com>
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* Sridhar Samudrala <sri@us.ibm.com>
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*
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* Rewritten to use libcrc32c by:
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* Vlad Yasevich <vladislav.yasevich@hp.com>
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*
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* Any bugs reported given to us we will try to fix... any fixes shared will
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* be incorporated into the next SCTP release.
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*/
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#include <linux/types.h>
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#include <net/sctp/sctp.h>
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#include <linux/crc32c.h>
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static inline __u32 sctp_start_cksum(__u8 *buffer, __u16 length)
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{
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__u32 crc = ~(__u32) 0;
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__u8 zero[sizeof(__u32)] = {0};
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/* Optimize this routine to be SCTP specific, knowing how
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* to skip the checksum field of the SCTP header.
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*/
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/* Calculate CRC up to the checksum. */
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crc = crc32c(crc, buffer, sizeof(struct sctphdr) - sizeof(__u32));
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/* Skip checksum field of the header. */
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crc = crc32c(crc, zero, sizeof(__u32));
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/* Calculate the rest of the CRC. */
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crc = crc32c(crc, &buffer[sizeof(struct sctphdr)],
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length - sizeof(struct sctphdr));
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return crc;
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}
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static inline __u32 sctp_update_cksum(__u8 *buffer, __u16 length, __u32 crc32)
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{
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return crc32c(crc32, buffer, length);
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}
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static inline __u32 sctp_end_cksum(__u32 crc32)
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{
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return ntohl(~crc32);
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}
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