Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751856AbdFJC7b (ORCPT ); Fri, 9 Jun 2017 22:59:31 -0400 Received: from frisell.zx2c4.com ([192.95.5.64]:52679 "EHLO frisell.zx2c4.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbdFJC73 (ORCPT ); Fri, 9 Jun 2017 22:59:29 -0400 From: "Jason A. Donenfeld" To: linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com Cc: "Jason A. Donenfeld" , Gilad Ben-Yossef , Greg Kroah-Hartman , stable@vger.kernel.org Subject: [PATCH 3/6] ccree: use constant time memory comparison for macs and tags Date: Sat, 10 Jun 2017 04:59:09 +0200 Message-Id: <20170610025912.6499-4-Jason@zx2c4.com> In-Reply-To: <20170610025912.6499-1-Jason@zx2c4.com> References: <20170610025912.6499-1-Jason@zx2c4.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4743 Lines: 100 Otherwise, we enable several different forgeries via timing attack. While the C inside this file is nearly incomprehensible, I did notice a high volume of "FIPS" and "NIST", which makes this kind of bug slightly more embarrassing. Signed-off-by: Jason A. Donenfeld Cc: Gilad Ben-Yossef Cc: Greg Kroah-Hartman Cc: stable@vger.kernel.org --- drivers/staging/ccree/ssi_fips_ll.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/staging/ccree/ssi_fips_ll.c b/drivers/staging/ccree/ssi_fips_ll.c index d573574bbb98..3310997d8e3e 100644 --- a/drivers/staging/ccree/ssi_fips_ll.c +++ b/drivers/staging/ccree/ssi_fips_ll.c @@ -19,6 +19,7 @@ This file defines the driver FIPS Low Level implmentaion functions, that executes the KAT. ***************************************************************/ #include +#include #include "ssi_driver.h" #include "ssi_fips_local.h" @@ -462,7 +463,7 @@ ssi_cipher_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffe } /* compare actual dout to expected */ - if (memcmp(virt_ctx->dout, cipherData->dataOut, cipherData->dataInSize) != 0) + if (crypto_memneq(virt_ctx->dout, cipherData->dataOut, cipherData->dataInSize)) { FIPS_LOG("dout comparison error %d - oprMode=%d, isAes=%d\n", i, cipherData->oprMode, cipherData->isAes); FIPS_LOG(" i expected received \n"); @@ -586,7 +587,7 @@ ssi_cmac_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, } /* compare actual mac result to expected */ - if (memcmp(virt_ctx->mac_res, cmac_data->mac_res, cmac_data->mac_res_size) != 0) + if (crypto_memneq(virt_ctx->mac_res, cmac_data->mac_res, cmac_data->mac_res_size)) { FIPS_LOG("comparison error %d - digest_size=%d \n", i, cmac_data->mac_res_size); FIPS_LOG(" i expected received \n"); @@ -760,7 +761,7 @@ ssi_hash_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, } /* compare actual mac result to expected */ - if (memcmp(virt_ctx->mac_res, hash_data->mac_res, digest_size) != 0) + if (crypto_memneq(virt_ctx->mac_res, hash_data->mac_res, digest_size)) { FIPS_LOG("comparison error %d - hash_mode=%d digest_size=%d \n", i, hash_data->hash_mode, digest_size); FIPS_LOG(" i expected received \n"); @@ -1093,7 +1094,7 @@ ssi_hmac_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, } /* compare actual mac result to expected */ - if (memcmp(virt_ctx->mac_res, hmac_data->mac_res, digest_size) != 0) + if (crypto_memneq(virt_ctx->mac_res, hmac_data->mac_res, digest_size)) { FIPS_LOG("comparison error %d - hash_mode=%d digest_size=%d \n", i, hmac_data->hash_mode, digest_size); FIPS_LOG(" i expected received \n"); @@ -1310,7 +1311,7 @@ ssi_ccm_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, } /* compare actual dout to expected */ - if (memcmp(virt_ctx->dout, ccmData->dataOut, ccmData->dataInSize) != 0) + if (crypto_memneq(virt_ctx->dout, ccmData->dataOut, ccmData->dataInSize)) { FIPS_LOG("dout comparison error %d - size=%d \n", i, ccmData->dataInSize); error = CC_REE_FIPS_ERROR_AESCCM_PUT; @@ -1318,7 +1319,7 @@ ssi_ccm_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, } /* compare actual mac result to expected */ - if (memcmp(virt_ctx->mac_res, ccmData->macResOut, ccmData->tagSize) != 0) + if (crypto_memneq(virt_ctx->mac_res, ccmData->macResOut, ccmData->tagSize)) { FIPS_LOG("mac_res comparison error %d - mac_size=%d \n", i, ccmData->tagSize); FIPS_LOG(" i expected received \n"); @@ -1633,7 +1634,7 @@ ssi_gcm_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, if (gcmData->direction == DRV_CRYPTO_DIRECTION_ENCRYPT) { /* compare actual dout to expected */ - if (memcmp(virt_ctx->dout, gcmData->dataOut, gcmData->dataInSize) != 0) + if (crypto_memneq(virt_ctx->dout, gcmData->dataOut, gcmData->dataInSize)) { FIPS_LOG("dout comparison error %d - size=%d \n", i, gcmData->dataInSize); FIPS_LOG(" i expected received \n"); @@ -1649,7 +1650,7 @@ ssi_gcm_fips_power_up_tests(struct ssi_drvdata *drvdata, void *cpu_addr_buffer, } /* compare actual mac result to expected */ - if (memcmp(virt_ctx->mac_res, gcmData->macResOut, gcmData->tagSize) != 0) + if (crypto_memneq(virt_ctx->mac_res, gcmData->macResOut, gcmData->tagSize)) { FIPS_LOG("mac_res comparison error %d - mac_size=%d \n", i, gcmData->tagSize); FIPS_LOG(" i expected received \n"); -- 2.13.1