From patchwork Wed Nov 12 04:26:03 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephan Mueller X-Patchwork-Id: 5285071 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Original-To: patchwork-linux-crypto@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 861A1C11AC for ; Wed, 12 Nov 2014 04:34:34 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 780552010B for ; Wed, 12 Nov 2014 04:34:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60DBE20108 for ; Wed, 12 Nov 2014 04:34:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754537AbaKLEco (ORCPT ); Tue, 11 Nov 2014 23:32:44 -0500 Received: from mail.eperm.de ([89.247.134.16]:54423 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754093AbaKLEcn (ORCPT ); Tue, 11 Nov 2014 23:32:43 -0500 X-AuthUser: sm@eperm.de Received: from tachyon.chronox.de by mail.eperm.de with [XMail 1.27 ESMTP Server] id for from ; Wed, 12 Nov 2014 05:32:39 +0100 From: Stephan Mueller To: Herbert Xu Cc: Marek Vasut , "David S. Miller" , Jason Cooper , Grant Likely , 'Geert Uytterhoeven' , "Joy M. Latten" , Jonathan Corbet , LKML , linux-crypto@vger.kernel.org Subject: [PATCH v3 05/13] crypto: Documentation - hash data structures Date: Wed, 12 Nov 2014 05:26:03 +0100 Message-ID: <4953641.UTgIXoZCd4@tachyon.chronox.de> User-Agent: KMail/4.14.2 (Linux/3.17.2-300.fc21.x86_64; KDE/4.14.2; x86_64; ; ) In-Reply-To: <1800066.efQ8hkST4U@tachyon.chronox.de> References: <1800066.efQ8hkST4U@tachyon.chronox.de> MIME-Version: 1.0 Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The hash data structures needed to be filled in by cipher developers are documented. Signed-off-by: Stephan Mueller --- include/crypto/hash.h | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 74b13ec..bf458fc 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -17,6 +17,28 @@ struct crypto_ahash; +/** + * DOC: Message Digest Algorithm Definitions + * + * These data structures define modular message digest algorithm + * implementations, managed via crypto_register_ahash(), + * crypto_register_shash(), crypto_unregister_ahash() and + * crypto_unregister_shash(). + */ + +/** + * struct hash_alg_common - define properties of message digest + * @digestsize: Size of the result of the transformation. A buffer of this size + * must be available to the @final and @finup calls, so they can + * store the resulting hash into it. For various predefined sizes, + * search include/crypto/ using + * git grep _DIGEST_SIZE include/crypto. + * @statesize: Size of the block for partial state of the transformation. A + * buffer of this size must be passed to the @export function as it + * will save the partial state of the transformation into it. On the + * other side, the @import function will load the state from a + * buffer of this size as well. + */ struct hash_alg_common { unsigned int digestsize; unsigned int statesize; @@ -37,6 +59,62 @@ struct ahash_request { void *__ctx[] CRYPTO_MINALIGN_ATTR; }; +/** + * struct ahash_alg - asynchronous message digest definition + * @init: Initialize the transformation context. Intended only to initialize the + * state of the HASH transformation at the begining. This shall fill in + * the internal structures used during the entire duration of the whole + * transformation. No data processing happens at this point. + * @update: Push a chunk of data into the driver for transformation. This + * function actually pushes blocks of data from upper layers into the + * driver, which then passes those to the hardware as seen fit. This + * function must not finalize the HASH transformation by calculating the + * final message digest as this only adds more data into the + * transformation. This function shall not modify the transformation + * context, as this function may be called in parallel with the same + * transformation object. Data processing can happen synchronously + * [SHASH] or asynchronously [AHASH] at this point. + * @final: Retrieve result from the driver. This function finalizes the + * transformation and retrieves the resulting hash from the driver and + * pushes it back to upper layers. No data processing happens at this + * point. + * @finup: Combination of @update and @final. This function is effectively a + * combination of @update and @final calls issued in sequence. As some + * hardware cannot do @update and @final separately, this callback was + * added to allow such hardware to be used at least by IPsec. Data + * processing can happen synchronously [SHASH] or asynchronously [AHASH] + * at this point. + * @digest: Combination of @init and @update and @final. This function + * effectively behaves as the entire chain of operations, @init, + * @update and @final issued in sequence. Just like @finup, this was + * added for hardware which cannot do even the @finup, but can only do + * the whole transformation in one run. Data processing can happen + * synchronously [SHASH] or asynchronously [AHASH] at this point. + * @setkey: Set optional key used by the hashing algorithm. Intended to push + * optional key used by the hashing algorithm from upper layers into + * the driver. This function can store the key in the transformation + * context or can outright program it into the hardware. In the former + * case, one must be careful to program the key into the hardware at + * appropriate time and one must be careful that .setkey() can be + * called multiple times during the existence of the transformation + * object. Not all hashing algorithms do implement this function as it + * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT + * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement + * this function. This function must be called before any other of the + * @init, @update, @final, @finup, @digest is called. No data + * processing happens at this point. + * @export: Export partial state of the transformation. This function dumps the + * entire state of the ongoing transformation into a provided block of + * data so it can be @import 'ed back later on. This is useful in case + * you want to save partial result of the transformation after + * processing certain amount of data and reload this partial result + * multiple times later on for multiple re-use. No data processing + * happens at this point. + * @import: Import partial state of the transformation. This function loads the + * entire state of the ongoing transformation from a provided block of + * data so the transformation can continue from this point onward. No + * data processing happens at this point. + */ struct ahash_alg { int (*init)(struct ahash_request *req); int (*update)(struct ahash_request *req); @@ -63,6 +141,23 @@ struct shash_desc { crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \ struct shash_desc *shash = (struct shash_desc *)__##shash##_desc +/** + * struct shash_alg - synchronous message digest definition + * @init: see struct ahash_alg + * @update: see struct ahash_alg + * @final: see struct ahash_alg + * @finup: see struct ahash_alg + * @digest: see struct ahash_alg + * @export: see struct ahash_alg + * @import: see struct ahash_alg + * @setkey: see struct ahash_alg + * @digestsize: see struct ahash_alg + * @statesize: see struct ahash_alg + * @dedcsize: Size of the operational state for the message digest. This state + * size is the memory size that needs to be allocated for + * shash_desc.__ctx + * @base: internally used + */ struct shash_alg { int (*init)(struct shash_desc *desc); int (*update)(struct shash_desc *desc, const u8 *data,