diff options
Diffstat (limited to 'include/net/sctp/checksum.h')
-rw-r--r-- | include/net/sctp/checksum.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/include/net/sctp/checksum.h b/include/net/sctp/checksum.h new file mode 100644 index 0000000..ba75c67 --- /dev/null +++ b/include/net/sctp/checksum.h @@ -0,0 +1,78 @@ +/* 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 <lksctp-developers@lists.sourceforge.net> + * + * Or submit a bug report through the following website: + * http://www.sf.net/projects/lksctp + * + * 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> + * + * Any bugs reported given to us we will try to fix... any fixes shared will + * be incorporated into the next SCTP release. + */ + +#include <linux/types.h> +#include <net/sctp/sctp.h> +#include <linux/crc32c.h> + +static inline __u32 sctp_start_cksum(__u8 *buffer, __u16 length) +{ + __u32 crc = ~(__u32) 0; + __u8 zero[sizeof(__u32)] = {0}; + + /* Optimize this routine to be SCTP specific, knowing how + * to skip the checksum field of the SCTP header. + */ + + /* Calculate CRC up to the checksum. */ + crc = crc32c(crc, buffer, sizeof(struct sctphdr) - sizeof(__u32)); + + /* Skip checksum field of the header. */ + crc = crc32c(crc, zero, sizeof(__u32)); + + /* Calculate the rest of the CRC. */ + crc = crc32c(crc, &buffer[sizeof(struct sctphdr)], + length - sizeof(struct sctphdr)); + return crc; +} + +static inline __u32 sctp_update_cksum(__u8 *buffer, __u16 length, __u32 crc32) +{ + return crc32c(crc32, buffer, length); +} + +static inline __u32 sctp_end_cksum(__u32 crc32) +{ + return ntohl(~crc32); +} |