From: "Darrick J. Wong" Subject: [PATCH 2/3] libcrc32c: Expose big-endian version of crc32c Date: Wed, 31 Aug 2011 17:33:30 -0700 Message-ID: <20110901003330.32645.32586.stgit@elm3c44.beaverton.ibm.com> References: <20110901003317.32645.16843.stgit@elm3c44.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Bob Pearson , linux-kernel , Mingming Cao , linux-crypto , linux-fsdevel , linux-ext4@vger.kernel.org To: Andreas Dilger , Herbert Xu , Theodore Tso , David Miller , "Darrick J. Wong" Return-path: In-Reply-To: <20110901003317.32645.16843.stgit@elm3c44.beaverton.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org Provide a big-endian version of crc32c for modules that want it. Signed-off-by: Darrick J. Wong --- include/linux/crc32c.h | 5 +++-- lib/libcrc32c.c | 43 ++++++++++++++++++++++++++++++++++--------- 2 files changed, 37 insertions(+), 11 deletions(-) diff --git a/include/linux/crc32c.h b/include/linux/crc32c.h index bd8b44d..33320e1 100644 --- a/include/linux/crc32c.h +++ b/include/linux/crc32c.h @@ -3,9 +3,10 @@ #include -extern u32 crc32c(u32 crc, const void *address, unsigned int length); +extern u32 crc32c_le(u32 crc, const void *address, unsigned int length); +extern u32 crc32c_be(u32 crc, const void *address, unsigned int length); /* This macro exists for backwards-compatibility. */ -#define crc32c_le crc32c +#define crc32c crc32c_le #endif /* _LINUX_CRC32C_H */ diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c index 244f548..e421ff5 100644 --- a/lib/libcrc32c.c +++ b/lib/libcrc32c.c @@ -37,17 +37,17 @@ #include #include -static struct crypto_shash *tfm; +static struct crypto_shash *tfm_le, *tfm_be; -u32 crc32c(u32 crc, const void *address, unsigned int length) +u32 crc32c_le(u32 crc, const void *address, unsigned int length) { struct { struct shash_desc shash; - char ctx[crypto_shash_descsize(tfm)]; + char ctx[crypto_shash_descsize(tfm_le)]; } desc; int err; - desc.shash.tfm = tfm; + desc.shash.tfm = tfm_le; desc.shash.flags = 0; *(u32 *)desc.ctx = crc; @@ -56,21 +56,46 @@ u32 crc32c(u32 crc, const void *address, unsigned int length) return *(u32 *)desc.ctx; } +EXPORT_SYMBOL(crc32c_le); -EXPORT_SYMBOL(crc32c); +u32 crc32c_be(u32 crc, const void *address, unsigned int length) +{ + struct { + struct shash_desc shash; + char ctx[crypto_shash_descsize(tfm_be)]; + } desc; + int err; + + desc.shash.tfm = tfm_be; + desc.shash.flags = 0; + *(u32 *)desc.ctx = crc; + + err = crypto_shash_update(&desc.shash, address, length); + BUG_ON(err); + + return *(u32 *)desc.ctx; +} +EXPORT_SYMBOL(crc32c_be); static int __init libcrc32c_mod_init(void) { - tfm = crypto_alloc_shash("crc32c", 0, 0); - if (IS_ERR(tfm)) - return PTR_ERR(tfm); + tfm_le = crypto_alloc_shash("crc32c", 0, 0); + if (IS_ERR(tfm_le)) + return PTR_ERR(tfm_le); + + tfm_be = crypto_alloc_shash("crc32c-be", 0, 0); + if (IS_ERR(tfm_be)) { + crypto_free_shash(tfm_le); + return PTR_ERR(tfm_be); + } return 0; } static void __exit libcrc32c_mod_fini(void) { - crypto_free_shash(tfm); + crypto_free_shash(tfm_be); + crypto_free_shash(tfm_le); } module_init(libcrc32c_mod_init);