From patchwork Wed Dec 8 22:39:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tedd Ho-Jeong An X-Patchwork-Id: 522298 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD3FFC433FE for ; Wed, 8 Dec 2021 22:39:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237914AbhLHWnB (ORCPT ); Wed, 8 Dec 2021 17:43:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233943AbhLHWnA (ORCPT ); Wed, 8 Dec 2021 17:43:00 -0500 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14798C061746 for ; Wed, 8 Dec 2021 14:39:28 -0800 (PST) Received: by mail-pf1-x432.google.com with SMTP id 8so3716115pfo.4 for ; Wed, 08 Dec 2021 14:39:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=cKwLht1AACZk6fY2XTuSMIVRhpq9sgqQiDy1auNtIpo=; b=G+G+CWTVOYKMm90YPOZBK1utnL4CDd8jHEL21/ltlxRblDUJH5eIdd+vfgK8ZgAdIP JkMeDrozhbt5h1IEwhB0FjmI6HmD2YrpIfUb72wirFGMucBMT1gIcKFq743a/C2HXKPX RTIQD0Q3d80qk4cU7L/nJtJ6cevhANiAVO0Me623CQF5FwYFoKGJ1eOIyq0yREsAiaxo 9QgBiMB1+EXvk0mMjeG1m7a+t+7k7AU4iK7nwwYn75cLVUinCRYIapWf+/AliiSCERwl 0VSaHoHgqooOIGcvamhTgYMvTUM1A3/slSGr7xqk1hPjHVQsYH5LCatnfRfXh+49QDLw 7UMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=cKwLht1AACZk6fY2XTuSMIVRhpq9sgqQiDy1auNtIpo=; b=nSHRT2ACKyUsuy6NkgQO24bLgkAKPRSXLbUrDWwiZf+g0vhNwgkMIFXXehoDHrgSj/ 93dAmGnoTz6+/qw8mePUBv8GDTYRNoNRf9HUqLbNF6XNhdDXPSyuHt6iSmTkFzqcPVoL i22ErdmBAKCgEr4XtS8ivoe+AK7O8zQO4l0oMXw7lNGdHqginbBnf+va3aar6+seCc/W saYF4WhCF2wsV0szApCd/4josoYxYVFzX8WsBGXirf7WpA3joPRqoa346zgbHA6MdG+T tzYN0YrlgJv9qvHX3ZkGTAI3v3lZhf5/qXpccVYMFOE9IQ51IgggntbFRixriL/9bITN ACYg== X-Gm-Message-State: AOAM531Slbc0b1KYdiLuvAVVvyf9B9mmOAJCKfinK5E+pRWWon+KvaTi otG/4z8s+AKdEBZhKlgeU7SXodZl16k= X-Google-Smtp-Source: ABdhPJzwdhgTAZCahqS73LnwB7ZO5qHFizt/347dY+mRNbakhK03KZEuvaRl4QXF/Ixo8C3LeBxhoQ== X-Received: by 2002:a62:d0c3:0:b0:4ad:51e9:963e with SMTP id p186-20020a62d0c3000000b004ad51e9963emr8176792pfg.36.1639003167298; Wed, 08 Dec 2021 14:39:27 -0800 (PST) Received: from localhost.localdomain ([2601:1c0:6a01:d830:6e9a:66a9:f3af:51f3]) by smtp.gmail.com with ESMTPSA id n16sm3757948pja.46.2021.12.08.14.39.26 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Dec 2021 14:39:26 -0800 (PST) From: Tedd Ho-Jeong An To: linux-bluetooth@vger.kernel.org Subject: [BlueZ V2 PATCH 1/5] emulator: Replace random number generation function Date: Wed, 8 Dec 2021 14:39:19 -0800 Message-Id: <20211208223923.519664-2-hj.tedd.an@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211208223923.519664-1-hj.tedd.an@gmail.com> References: <20211208223923.519664-1-hj.tedd.an@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org From: Tedd Ho-Jeong An This patch replaces the rand() function to the getrandom() syscall. It was reported by the Coverity scan rand() should not be used for security-related applications, because linear congruential algorithms are too easy to break --- emulator/le.c | 11 +++++++++-- emulator/phy.c | 10 ++++++++-- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/emulator/le.c b/emulator/le.c index 07a44c5f1..f8f313f2c 100644 --- a/emulator/le.c +++ b/emulator/le.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include "lib/bluetooth.h" @@ -503,11 +504,17 @@ static void send_adv_pkt(struct bt_le *hci, uint8_t channel) static unsigned int get_adv_delay(void) { + unsigned int val; + /* The advertising delay is a pseudo-random value with a range * of 0 ms to 10 ms generated for each advertising event. */ - srand(time(NULL)); - return (rand() % 11); + if (getrandom(&val, sizeof(val), 0) < 0) { + /* If it fails to get the random number, use a static value */ + val = 5; + } + + return (val % 11); } static void adv_timeout_callback(int id, void *user_data) diff --git a/emulator/phy.c b/emulator/phy.c index 2ae6ad3a2..44cace438 100644 --- a/emulator/phy.c +++ b/emulator/phy.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -173,8 +174,13 @@ struct bt_phy *bt_phy_new(void) mainloop_add_fd(phy->rx_fd, EPOLLIN, phy_rx_callback, phy, NULL); if (!get_random_bytes(&phy->id, sizeof(phy->id))) { - srandom(time(NULL)); - phy->id = random(); + if (getrandom(&phy->id, sizeof(phy->id), 0) < 0) { + mainloop_remove_fd(phy->rx_fd); + close(phy->tx_fd); + close(phy->rx_fd); + free(phy); + return NULL; + } } bt_phy_send(phy, BT_PHY_PKT_NULL, NULL, 0);