From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx07-00178001.pphosted.com (mx08-00178001.pphosted.com [91.207.212.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 730F92D321A; Wed, 25 Jun 2025 16:31:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.207.212.93 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750869084; cv=none; b=dNghOEJpW0dF7SMuICok794K9/d3bHS+6IkxuUvxDaSjHQFowW9Qpu5qaOYL/aQhKsR1VWfJ4xIVjFcbjmqtvQwmGPhB3spE1XOia3cKLY7oVeHZiGp0/EZYm36eLuYvGAMpDfMFmK2UjBtwW9X4KJRPqD9OgPDIWa3aUU/QWbA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750869084; c=relaxed/simple; bh=Zj0315h1+Ugs/regjOq5i5dG08rRrPa2Cmoyc3sj6SU=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=WWurkyqeuC934uhqmdun4PCPdL8rCPrUn3yuaYv7r1TkLl5FJ0n5kUKIjPzsLdedKKPIee/pgWLglhryhoIoO/XH9SSQ2G1UIMGc5sCl61FjDSBHkycjnEJU3qDfqHyDwm+Amtxjo2jFrSQSwqpzuVe7uiRMnRUf3pJcCZotylE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com; spf=pass smtp.mailfrom=foss.st.com; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b=snHTUn8v; arc=none smtp.client-ip=91.207.212.93 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foss.st.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="snHTUn8v" Received: from pps.filterd (m0046661.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 55PFvITO009480; Wed, 25 Jun 2025 18:30:47 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=selector1; bh= Ar5cY3eqwri9AVFjIOQsbTDZ2wnQ244y0/ufHL/uq/A=; b=snHTUn8v8zy4BnVf bkKsMzALzX/hWB50aMj4MxIHi4bX+SsAYGY3Ta0qS9W+Qov86Hf3IFmC6wwbjXKe z+7twjq4QjRMRhSZLUxgBzx2nUR3tozW2d6dCqKxErksVbCQU6VU/JiwQwzNDwcn U/1p4bdqn33j4ByolMt6WwqjLdE3h61JA8R5yccQhLkGEskbTqOvCPUA7/8p3XmS 3qkplYuF9MJHqCdFCqu0QAWkYnOvwX3wSSg4FJ6n+6+HrXVAi9jrPcnDQBoDD8cW 6WJ6dlJDiRbtJNS8vh0xlq+UK3j8XGCWgrXg1kalJWT759R+wTleuCh44x8N8dF3 PYWGSA== Received: from beta.dmz-ap.st.com (beta.dmz-ap.st.com [138.198.100.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 47dkmjtf7e-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 25 Jun 2025 18:30:47 +0200 (MEST) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id 5E1194002D; Wed, 25 Jun 2025 18:29:58 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node3.st.com [10.75.129.71]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id DD36CBF53B0; Wed, 25 Jun 2025 18:29:23 +0200 (CEST) Received: from [10.48.86.103] (10.48.86.103) by SHFDAG1NODE3.st.com (10.75.129.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39; Wed, 25 Jun 2025 18:29:23 +0200 Message-ID: Date: Wed, 25 Jun 2025 18:29:17 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] fscrypt: don't use hardware offload Crypto API drivers To: Eric Biggers CC: , , , , , , References: <20250611205859.80819-1-ebiggers@kernel.org> <8f4c2f36-71af-4c84-bcee-2554cea991d0@foss.st.com> <20250613144239.GA1287@sol> Content-Language: en-US From: Maxime MERE In-Reply-To: <20250613144239.GA1287@sol> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: EQNCAS1NODE4.st.com (10.75.129.82) To SHFDAG1NODE3.st.com (10.75.129.71) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.7,FMLib:17.12.80.40 definitions=2025-06-25_05,2025-06-25_01,2025-03-28_01 On 6/13/25 16:42, Eric Biggers wrote: > Honestly, the responses to this thread so far have made it even more clear that > this patch is the right decision. The chaining system I previously presented is just an example intended to demonstrate the value of hardware drivers in the context of ST platforms. The key point is that our hardware IP allows us to securely embed encryption keys directly in hardware, making sure they are never visible or accessible from Linux, which runs in a non-secure environment. Our software architectures rely on a Secure OS running in parallel with Linux, similar to what is done on Android. This Secure OS is responsible for sensitive cryptographic operations. This Secure OS can manages the keys with a dedicated hardware peripheral (SAES). The Linux side never sees the keys directly. Instead, the Secure OS prepares the keys and shares them securely with the cryptographic engine (CRYP) through a dedicated hardware bus. This architecture improves security boundary: keys isolated from the non-secure Linux environment. But decryption can be processed by the linux kernel. In addition, ST’s hardware crypto peripherals come with built-in protections against side-channel attacks and have been certified with SESIP and PSA level 3 security assurance, providing a level of security difficult to achieve with software alone. Regarding robustness and maintenance, ST ensures regular updates of its drivers and can fix any reported bugs. We have conducted internal tests with dm-crypt that demonstrate the proper functioning of these drivers for this type of application. Maxime