From patchwork Thu Oct 15 09:24:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "tianjia.zhang" X-Patchwork-Id: 11838817 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B824D14B2 for ; Thu, 15 Oct 2020 09:24:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 96BEE21D7F for ; Thu, 15 Oct 2020 09:24:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726583AbgJOJYn (ORCPT ); Thu, 15 Oct 2020 05:24:43 -0400 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:49307 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726426AbgJOJYn (ORCPT ); Thu, 15 Oct 2020 05:24:43 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04420;MF=tianjia.zhang@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0UC5QX1p_1602753881; Received: from localhost(mailfrom:tianjia.zhang@linux.alibaba.com fp:SMTPD_---0UC5QX1p_1602753881) by smtp.aliyun-inc.com(127.0.0.1); Thu, 15 Oct 2020 17:24:41 +0800 From: Tianjia Zhang To: Herbert Xu , "David S. Miller" , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Tianjia Zhang Subject: [PATCH] crypto: sm2 - remove unnecessary reset operations Date: Thu, 15 Oct 2020 17:24:41 +0800 Message-Id: <20201015092441.12939-1-tianjia.zhang@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.3.ge56e4f7 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org This is an algorithm optimization. The reset operation when setting the public key is repeated and redundant, so remove it. At the same time, `sm2_ecc_os2ec()` is optimized to make the function more simpler and more in line with the Linux code style. Signed-off-by: Tianjia Zhang --- crypto/sm2.c | 75 ++++++++++++++++++++-------------------------------- 1 file changed, 29 insertions(+), 46 deletions(-) diff --git a/crypto/sm2.c b/crypto/sm2.c index 767e160333f6..b21addc3ac06 100644 --- a/crypto/sm2.c +++ b/crypto/sm2.c @@ -119,12 +119,6 @@ static void sm2_ec_ctx_deinit(struct mpi_ec_ctx *ec) memset(ec, 0, sizeof(*ec)); } -static int sm2_ec_ctx_reset(struct mpi_ec_ctx *ec) -{ - sm2_ec_ctx_deinit(ec); - return sm2_ec_ctx_init(ec); -} - /* RESULT must have been initialized and is set on success to the * point given by VALUE. */ @@ -132,55 +126,48 @@ static int sm2_ecc_os2ec(MPI_POINT result, MPI value) { int rc; size_t n; - const unsigned char *buf; - unsigned char *buf_memory; + unsigned char *buf; MPI x, y; - n = (mpi_get_nbits(value)+7)/8; - buf_memory = kmalloc(n, GFP_KERNEL); - rc = mpi_print(GCRYMPI_FMT_USG, buf_memory, n, &n, value); - if (rc) { - kfree(buf_memory); - return rc; - } - buf = buf_memory; + n = MPI_NBYTES(value); + buf = kmalloc(n, GFP_KERNEL); + if (!buf) + return -ENOMEM; - if (n < 1) { - kfree(buf_memory); - return -EINVAL; - } - if (*buf != 4) { - kfree(buf_memory); - return -EINVAL; /* No support for point compression. */ - } - if (((n-1)%2)) { - kfree(buf_memory); - return -EINVAL; - } - n = (n-1)/2; + rc = mpi_print(GCRYMPI_FMT_USG, buf, n, &n, value); + if (rc) + goto err_freebuf; + + rc = -EINVAL; + if (n < 1 || ((n - 1) % 2)) + goto err_freebuf; + /* No support for point compression */ + if (*buf != 0x4) + goto err_freebuf; + + rc = -ENOMEM; + n = (n - 1) / 2; x = mpi_read_raw_data(buf + 1, n); - if (!x) { - kfree(buf_memory); - return -ENOMEM; - } + if (!x) + goto err_freebuf; y = mpi_read_raw_data(buf + 1 + n, n); - kfree(buf_memory); - if (!y) { - mpi_free(x); - return -ENOMEM; - } + if (!y) + goto err_freex; mpi_normalize(x); mpi_normalize(y); - mpi_set(result->x, x); mpi_set(result->y, y); mpi_set_ui(result->z, 1); - mpi_free(x); - mpi_free(y); + rc = 0; - return 0; + mpi_free(y); +err_freex: + mpi_free(x); +err_freebuf: + kfree(buf); + return rc; } struct sm2_signature_ctx { @@ -399,10 +386,6 @@ static int sm2_set_pub_key(struct crypto_akcipher *tfm, MPI a; int rc; - rc = sm2_ec_ctx_reset(ec); - if (rc) - return rc; - ec->Q = mpi_point_new(0); if (!ec->Q) return -ENOMEM;