From: Benny Halevy Subject: Re: [PATCH] libcrc32c: keep intermediate crc state in cpu order Date: Thu, 08 Nov 2007 21:29:10 +0200 Message-ID: <47336386.50406@panasas.com> References: <473186E9.5080300@panasas.com> <4731A5C5.3030109@panasas.com> <4731D387.5090901@panasas.com> <20071108001400O.tomof@acm.org> <4731DA0C.5090702@panasas.com> <4731FD41.1090704@panasas.com> <4732C6D2.5000904@panasas.com> <47335857.20303@mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: open-iscsi@googlegroups.com, linux-crypto@vger.kernel.org, "David S. Miller" , Clay Haapala , fujita.tomonori@lab.ntt.co.jp, michaelc@cs.wisc.edu, Herbert Xu To: Dave Jiang Return-path: Received: from gw-colo-pa.panasas.com ([66.238.117.130]:1390 "EHLO cassoulet.panasas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759958AbXKHTh4 (ORCPT ); Thu, 8 Nov 2007 14:37:56 -0500 In-Reply-To: <47335857.20303@mvista.com> Sender: linux-crypto-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org On Nov. 08, 2007, 20:41 +0200, Dave Jiang wrote: > Resolved my issue with BE open-iscsi initiator and LE IET target. Thanks! Super! Thanks for testing! And many thanks to Tomo for identifying the byte-order problem in the crypto code. Benny > > Benny Halevy wrote: >> crypto/crc32.c:chksum_final() is computing the digest as >> *(__le32 *)out = ~cpu_to_le32(mctx->crc); >> so the low-level crc32c_le routines should just keep >> the crc in cpu order, otherwise it is getting swabbed >> one too many times on big-endian machines. >> >> Signed-off-by: Benny Halevy >> --- >> lib/libcrc32c.c | 7 ++----- >> 1 files changed, 2 insertions(+), 5 deletions(-) >> >> diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c >> index 802f11f..b5c3287 100644 >> --- a/lib/libcrc32c.c >> +++ b/lib/libcrc32c.c >> @@ -33,7 +33,6 @@ >> #include >> #include >> #include >> -#include >> >> MODULE_AUTHOR("Clay Haapala "); >> MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations"); >> @@ -161,15 +160,13 @@ static const u32 crc32c_table[256] = { >> */ >> >> u32 __pure >> -crc32c_le(u32 seed, unsigned char const *data, size_t length) >> +crc32c_le(u32 crc, unsigned char const *data, size_t length) >> { >> - u32 crc = __cpu_to_le32(seed); >> - >> while (length--) >> crc = >> crc32c_table[(crc ^ *data++) & 0xFFL] ^ (crc >> 8); >> >> - return __le32_to_cpu(crc); >> + return crc; >> } >> >> #endif /* CRC_LE_BITS == 8 */ > >