From patchwork Sun Mar 22 12:04:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: George Spelvin X-Patchwork-Id: 11451661 X-Patchwork-Delegate: johannes@sipsolutions.net 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 CEB1F913 for ; Sun, 22 Mar 2020 12:14:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ABF7E20637 for ; Sun, 22 Mar 2020 12:14:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726901AbgCVMOY (ORCPT ); Sun, 22 Mar 2020 08:14:24 -0400 Received: from mx.sdf.org ([205.166.94.20]:55775 "EHLO mx.sdf.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725997AbgCVMOY (ORCPT ); Sun, 22 Mar 2020 08:14:24 -0400 X-Greylist: delayed 603 seconds by postgrey-1.27 at vger.kernel.org; Sun, 22 Mar 2020 08:14:23 EDT Received: from sdf.org (IDENT:lkml@sdf.lonestar.org [205.166.94.16]) by mx.sdf.org (8.15.2/8.14.5) with ESMTPS id 02MC48xc007050 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits) verified NO); Sun, 22 Mar 2020 12:04:08 GMT Received: (from lkml@localhost) by sdf.org (8.15.2/8.12.8/Submit) id 02MC4847008847; Sun, 22 Mar 2020 12:04:08 GMT Date: Sun, 22 Mar 2020 12:04:08 +0000 From: George Spelvin To: Adham Abozaeid , Ajay Singh Cc: linux-wireless@vger.kernel.org, lkml@sdf.org Subject: [PATCH] wilc1000: Use crc7 in lib/ rather than a private copy Message-ID: <20200322120408.GA19411@SDF.ORG> MIME-Version: 1.0 Content-Disposition: inline Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org The code in lib/ is the desired polynomial, and even includes the 1-bit left shift in the table rather than needing to code it explicitly. Signed-off-by: George Spelvin Cc: Adham Abozaeid Cc: Ajay Singh Cc: linux-wireless@vger.kernel.org --- Just a drive-by fix I happened to spot. Another possible bug I found in the code is in wilc_wfi_cfg_tx_vendor_spec: get_random_bytes(&priv->p2p.local_random, 1); priv->p2p.local_random++; What is the point of the increment? Since local_random is an 8-bit variable, the result is 8 random bits in the range [0..255], the same thing that was there before the increment. Also, I was thinking it could be replaced by prandom_u32(); does this application call for crypto-grade randomness? drivers/staging/wilc1000/Kconfig | 1 + drivers/staging/wilc1000/spi.c | 56 ++------------------------------ 2 files changed, 3 insertions(+), 54 deletions(-) diff --git a/drivers/staging/wilc1000/Kconfig b/drivers/staging/wilc1000/Kconfig index 59e58550d1397..09242cc7c04b7 100644 --- a/drivers/staging/wilc1000/Kconfig +++ b/drivers/staging/wilc1000/Kconfig @@ -22,6 +22,7 @@ config WILC1000_SPI tristate "Atmel WILC1000 SPI (WiFi only)" depends on CFG80211 && INET && SPI select WILC1000 + select CRC7 help This module adds support for the SPI interface of adapters using WILC1000 chipset. The Atmel WILC1000 has a Serial Peripheral diff --git a/drivers/staging/wilc1000/spi.c b/drivers/staging/wilc1000/spi.c index 55f8757325f0f..431aee27e7212 100644 --- a/drivers/staging/wilc1000/spi.c +++ b/drivers/staging/wilc1000/spi.c @@ -6,6 +6,7 @@ #include #include +#include #include "netdev.h" #include "cfg80211.h" @@ -18,59 +19,6 @@ struct wilc_spi { static const struct wilc_hif_func wilc_hif_spi; -/******************************************** - * - * Crc7 - * - ********************************************/ - -static const u8 crc7_syndrome_table[256] = { - 0x00, 0x09, 0x12, 0x1b, 0x24, 0x2d, 0x36, 0x3f, - 0x48, 0x41, 0x5a, 0x53, 0x6c, 0x65, 0x7e, 0x77, - 0x19, 0x10, 0x0b, 0x02, 0x3d, 0x34, 0x2f, 0x26, - 0x51, 0x58, 0x43, 0x4a, 0x75, 0x7c, 0x67, 0x6e, - 0x32, 0x3b, 0x20, 0x29, 0x16, 0x1f, 0x04, 0x0d, - 0x7a, 0x73, 0x68, 0x61, 0x5e, 0x57, 0x4c, 0x45, - 0x2b, 0x22, 0x39, 0x30, 0x0f, 0x06, 0x1d, 0x14, - 0x63, 0x6a, 0x71, 0x78, 0x47, 0x4e, 0x55, 0x5c, - 0x64, 0x6d, 0x76, 0x7f, 0x40, 0x49, 0x52, 0x5b, - 0x2c, 0x25, 0x3e, 0x37, 0x08, 0x01, 0x1a, 0x13, - 0x7d, 0x74, 0x6f, 0x66, 0x59, 0x50, 0x4b, 0x42, - 0x35, 0x3c, 0x27, 0x2e, 0x11, 0x18, 0x03, 0x0a, - 0x56, 0x5f, 0x44, 0x4d, 0x72, 0x7b, 0x60, 0x69, - 0x1e, 0x17, 0x0c, 0x05, 0x3a, 0x33, 0x28, 0x21, - 0x4f, 0x46, 0x5d, 0x54, 0x6b, 0x62, 0x79, 0x70, - 0x07, 0x0e, 0x15, 0x1c, 0x23, 0x2a, 0x31, 0x38, - 0x41, 0x48, 0x53, 0x5a, 0x65, 0x6c, 0x77, 0x7e, - 0x09, 0x00, 0x1b, 0x12, 0x2d, 0x24, 0x3f, 0x36, - 0x58, 0x51, 0x4a, 0x43, 0x7c, 0x75, 0x6e, 0x67, - 0x10, 0x19, 0x02, 0x0b, 0x34, 0x3d, 0x26, 0x2f, - 0x73, 0x7a, 0x61, 0x68, 0x57, 0x5e, 0x45, 0x4c, - 0x3b, 0x32, 0x29, 0x20, 0x1f, 0x16, 0x0d, 0x04, - 0x6a, 0x63, 0x78, 0x71, 0x4e, 0x47, 0x5c, 0x55, - 0x22, 0x2b, 0x30, 0x39, 0x06, 0x0f, 0x14, 0x1d, - 0x25, 0x2c, 0x37, 0x3e, 0x01, 0x08, 0x13, 0x1a, - 0x6d, 0x64, 0x7f, 0x76, 0x49, 0x40, 0x5b, 0x52, - 0x3c, 0x35, 0x2e, 0x27, 0x18, 0x11, 0x0a, 0x03, - 0x74, 0x7d, 0x66, 0x6f, 0x50, 0x59, 0x42, 0x4b, - 0x17, 0x1e, 0x05, 0x0c, 0x33, 0x3a, 0x21, 0x28, - 0x5f, 0x56, 0x4d, 0x44, 0x7b, 0x72, 0x69, 0x60, - 0x0e, 0x07, 0x1c, 0x15, 0x2a, 0x23, 0x38, 0x31, - 0x46, 0x4f, 0x54, 0x5d, 0x62, 0x6b, 0x70, 0x79 -}; - -static u8 crc7_byte(u8 crc, u8 data) -{ - return crc7_syndrome_table[(crc << 1) ^ data]; -} - -static u8 crc7(u8 crc, const u8 *buffer, u32 len) -{ - while (len--) - crc = crc7_byte(crc, *buffer++); - return crc; -} - /******************************************** * * Spi protocol Function @@ -396,7 +344,7 @@ static int spi_cmd_complete(struct wilc *wilc, u8 cmd, u32 adr, u8 *b, u32 sz, return result; if (!spi_priv->crc_off) - wb[len - 1] = (crc7(0x7f, (const u8 *)&wb[0], len - 1)) << 1; + wb[len - 1] = crc7_be(0xfe, wb, len - 1); else len -= 1;