From nobody Tue Dec 16 22:12:19 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B542F235079; Fri, 30 May 2025 16:10:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748621423; cv=none; b=tD3veXPr459F4PDJb6RogKsLa4JDwwGYtdRUNCdU+zHlmCqBOL7byPCiQeT47vnIAXKYYg1t4Tmk6dNsVyXOkvU6llRqqP6m2KDi+r0nNWcUaf5X5QRwy3E5XLd5vCmIXNBwCOLFWUrwDY8hidX/XbOOMWF+xRYkRNlkCo5714E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748621423; c=relaxed/simple; bh=HrdqjSxm8EooDpiNXtzK0jxkcPuOsCkYBWG/5ijU9Vs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=CD5FzBMT3OOlMC/qo6HRwEZh/R+yhW5bU8F1Bf7ad39t9Hl9VSHtgajF4AgWUKIBe5XW7x1K4UiY1Rc4F0S1Oc/byQWOY/JBVXQL85BLNQ4dk5TPKLy5pS5DRVvwyXZfuKAWs9fcUd/24NBoU+/Igw/Q7tw7v5gtUg54FO+1pLQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rENlBUYw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rENlBUYw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D5F3C4CEE9; Fri, 30 May 2025 16:10:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1748621423; bh=HrdqjSxm8EooDpiNXtzK0jxkcPuOsCkYBWG/5ijU9Vs=; h=From:To:Cc:Subject:Date:From; b=rENlBUYwKHO69VBi1tQWKmiFmZKnZkVvbn5HBMT3R64ZgNRBclAKQkB/9eMyW/pKk uohi9UOcylwxV1RCNjbGiCFdkUBAipd/F5KH1jfJyZjnBBb6B9aGp0EblFKvPX2KHR hdJ7E1KATkw9G7mzMT7ugxwZ2pC5nk/TBrgJ7sAgaE4NSMI5X8bm/2EcYjMOx79mSC lrudjoTV35igerXVBEFaThQ7dsDxrM9DH36pFn1tktsxlfnOXDrfO6udw3u9WyvZh7 F/P864zWPv4vZ3QYq/1c361XXgW68Dlc7YXVY5xpBJ9Wce2ES+xewr3dL54PxwcCUn HuG3XXOrGNAfw== From: Eric Biggers To: linux-kernel@vger.kernel.org Cc: linux-crypto@vger.kernel.org, Ard Biesheuvel Subject: [PATCH] crypto/crc32: register only one shash_alg Date: Fri, 30 May 2025 09:09:40 -0700 Message-ID: <20250530160940.12761-1-ebiggers@kernel.org> X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Eric Biggers Stop unnecessarily registering a "crc32-generic" shash_alg when a "crc32-$(ARCH)" shash_alg is registered too. While every algorithm does need to have a generic implementation to ensure uniformity of support across platforms, that doesn't mean that we need to make the generic implementation available through crypto_shash when an optimized implementation is also available. Registering the generic shash_alg did allow users of the crypto_shash or crypto_ahash APIs to request the generic implementation specifically, instead of an optimized one. However, the only known use case for that was the differential fuzz tests in crypto/testmgr.c. Equivalent test coverage is now provided by crc_kunit. Signed-off-by: Eric Biggers --- I'm planning to take this through the crc tree. crypto/crc32.c | 69 ++++++++------------------------------------------ 1 file changed, 11 insertions(+), 58 deletions(-) diff --git a/crypto/crc32.c b/crypto/crc32.c index cc371d42601fd..b61d5663d0bac 100644 --- a/crypto/crc32.c +++ b/crypto/crc32.c @@ -57,33 +57,16 @@ static int crc32_init(struct shash_desc *desc) static int crc32_update(struct shash_desc *desc, const u8 *data, unsigned int len) { u32 *crcp =3D shash_desc_ctx(desc); =20 - *crcp =3D crc32_le_base(*crcp, data, len); - return 0; -} - -static int crc32_update_arch(struct shash_desc *desc, const u8 *data, - unsigned int len) -{ - u32 *crcp =3D shash_desc_ctx(desc); - *crcp =3D crc32_le(*crcp, data, len); return 0; } =20 /* No final XOR 0xFFFFFFFF, like crc32_le */ -static int __crc32_finup(u32 *crcp, const u8 *data, unsigned int len, - u8 *out) -{ - put_unaligned_le32(crc32_le_base(*crcp, data, len), out); - return 0; -} - -static int __crc32_finup_arch(u32 *crcp, const u8 *data, unsigned int len, - u8 *out) +static int __crc32_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *= out) { put_unaligned_le32(crc32_le(*crcp, data, len), out); return 0; } =20 @@ -91,16 +74,10 @@ static int crc32_finup(struct shash_desc *desc, const u= 8 *data, unsigned int len, u8 *out) { return __crc32_finup(shash_desc_ctx(desc), data, len, out); } =20 -static int crc32_finup_arch(struct shash_desc *desc, const u8 *data, - unsigned int len, u8 *out) -{ - return __crc32_finup_arch(shash_desc_ctx(desc), data, len, out); -} - static int crc32_final(struct shash_desc *desc, u8 *out) { u32 *crcp =3D shash_desc_ctx(desc); =20 put_unaligned_le32(*crcp, out); @@ -111,72 +88,48 @@ static int crc32_digest(struct shash_desc *desc, const= u8 *data, unsigned int len, u8 *out) { return __crc32_finup(crypto_shash_ctx(desc->tfm), data, len, out); } =20 -static int crc32_digest_arch(struct shash_desc *desc, const u8 *data, - unsigned int len, u8 *out) -{ - return __crc32_finup_arch(crypto_shash_ctx(desc->tfm), data, len, out); -} - -static struct shash_alg algs[] =3D {{ +static struct shash_alg alg =3D { .setkey =3D crc32_setkey, .init =3D crc32_init, .update =3D crc32_update, .final =3D crc32_final, .finup =3D crc32_finup, .digest =3D crc32_digest, .descsize =3D sizeof(u32), .digestsize =3D CHKSUM_DIGEST_SIZE, =20 .base.cra_name =3D "crc32", - .base.cra_driver_name =3D "crc32-generic", .base.cra_priority =3D 100, .base.cra_flags =3D CRYPTO_ALG_OPTIONAL_KEY, .base.cra_blocksize =3D CHKSUM_BLOCK_SIZE, .base.cra_ctxsize =3D sizeof(u32), .base.cra_module =3D THIS_MODULE, .base.cra_init =3D crc32_cra_init, -}, { - .setkey =3D crc32_setkey, - .init =3D crc32_init, - .update =3D crc32_update_arch, - .final =3D crc32_final, - .finup =3D crc32_finup_arch, - .digest =3D crc32_digest_arch, - .descsize =3D sizeof(u32), - .digestsize =3D CHKSUM_DIGEST_SIZE, - - .base.cra_name =3D "crc32", - .base.cra_driver_name =3D "crc32-" __stringify(ARCH), - .base.cra_priority =3D 150, - .base.cra_flags =3D CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_blocksize =3D CHKSUM_BLOCK_SIZE, - .base.cra_ctxsize =3D sizeof(u32), - .base.cra_module =3D THIS_MODULE, - .base.cra_init =3D crc32_cra_init, -}}; - -static int num_algs; +}; =20 static int __init crc32_mod_init(void) { - /* register the arch flavor only if it differs from the generic one */ - num_algs =3D 1 + ((crc32_optimizations() & CRC32_LE_OPTIMIZATION) !=3D 0); + const char *driver_name =3D + (crc32_optimizations() & CRC32_LE_OPTIMIZATION) ? + "crc32-" __stringify(ARCH) : + "crc32-generic"; + + strscpy(alg.base.cra_driver_name, driver_name, CRYPTO_MAX_ALG_NAME); =20 - return crypto_register_shashes(algs, num_algs); + return crypto_register_shash(&alg); } =20 static void __exit crc32_mod_fini(void) { - crypto_unregister_shashes(algs, num_algs); + crypto_unregister_shash(&alg); } =20 module_init(crc32_mod_init); module_exit(crc32_mod_fini); =20 MODULE_AUTHOR("Alexander Boyko "); MODULE_DESCRIPTION("CRC32 calculations wrapper for lib/crc32"); MODULE_LICENSE("GPL"); MODULE_ALIAS_CRYPTO("crc32"); -MODULE_ALIAS_CRYPTO("crc32-generic"); base-commit: f66bc387efbee59978e076ce9bf123ac353b389c --=20 2.49.0