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 000000000..4a5b9a306 --- /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, see + * <http://www.gnu.org/licenses/>. + * + * 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__ */ |