From patchwork Sun May 19 16:04:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hsin-Yi Wang X-Patchwork-Id: 10949479 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1A47D112C for ; Sun, 19 May 2019 16:05:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 072D526B39 for ; Sun, 19 May 2019 16:05:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EC0C22845E; Sun, 19 May 2019 16:05:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 610D026B39 for ; Sun, 19 May 2019 16:05:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=KN01NZoootDbSFOa9As8JBBPu8xrOAtTiE/gwpfat0E=; b=ZZ1QMty3+4KaWn dzUBvkhg2p/SHRCsjbZShOMFryrOuuhwkPJ4xByy/4qdpbxhuC2+Ki2ufipcwQ4B+7NjxK7/4K5B9 6MxbMJm7SKRvb6oeYthkYwnzR+P334iKwnautM+TvjF4dMrn9HTUNr6RQtAWuYANecPBBzV7rxCUf H3Y5gfzo0j5nBx9FoyTju6iqUObSNr65G6MtBsDu7cRRANRX0eq7eLlCTaCMPlvBPp3iQ+T2wNSqw iO40f2k399lQyzF+gSZJFhu1AhjDfXPS7Xi4qWRy2xxNcEkPMsn+1Wa75pogRrba21xkuQxwdk66Y OlTLBLUREcOBPNMdghrg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hSOJJ-0006FM-Lj; Sun, 19 May 2019 16:05:17 +0000 Received: from mail-pf1-x444.google.com ([2607:f8b0:4864:20::444]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hSOJE-00069A-0Y for linux-arm-kernel@lists.infradead.org; Sun, 19 May 2019 16:05:15 +0000 Received: by mail-pf1-x444.google.com with SMTP id t87so6014264pfa.2 for ; Sun, 19 May 2019 09:05:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=gCFKWEfomzC/p8Cp2zu9+tMCVjDMCf+wEVZ+N8bS+5w=; b=T/7IReFvKjKaF14U1oGtHscyU/22SyS4d7KmRC5r07CtvxiAbogbfeuIroE/8H2wz0 nLTWIIZriLKgXnWDXlyBKjqUAsl9SsAMjTTs4IMZaZBFvDrupg39ZL7WTW3wXN2yB8aj f8BzAcUBvMPTNeGH08JCB9Xs2xfvt2oFwNK1Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=gCFKWEfomzC/p8Cp2zu9+tMCVjDMCf+wEVZ+N8bS+5w=; b=SPjzfkYbPYVHSaXhr2CCIS3OmHVrJsuFH1iR6vblM/Zp/NMuDTHDqqtTH4rcx779/Q nA2spXTmYqLHU+SXe9IAgPE6gUDzQ2nV2dEXyZdvnoWQzmUlDHCMfXCMOnhbG3+oali/ KVfbC1csCgz/yzI9OMdSmB2CuE3nk5hMH628NelzHANXeLeyygQNhtA7c38nAf6cyFsD dNE6vj3J1F3BdXs94ZMWUw3M6s+UmBqsfydMt3ef7N4vrQchxJ6H5UuBZgqr/6aCgiUR mpi0F2ZRt7AY0KHJRtCNmz7TbBP4i/Xayz8edPQuQrtQbGeCHC43cp8brqwqyT99t9D+ QYIg== X-Gm-Message-State: APjAAAUh4XRd06I7UlO59zseuI0U0V9g3c2gdIFUAaIE8jiJ/G1sDTgk FgzVB5PAxmvTqk7lfsoexeq+KKrk78W6ng== X-Google-Smtp-Source: APXvYqy+Gmvo5+tw39P1k0XyadavsTQNx3uwPq73xdTjt//OfTcVKyZMNiRhgh9F9ySQ8HBIePPR/g== X-Received: by 2002:a63:a08:: with SMTP id 8mr69721219pgk.46.1558281910923; Sun, 19 May 2019 09:05:10 -0700 (PDT) Received: from hsinyi-z840.tpe.corp.google.com ([2401:fa00:1:10:b852:bd51:9305:4261]) by smtp.gmail.com with ESMTPSA id b23sm17547007pfi.6.2019.05.19.09.05.07 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 19 May 2019 09:05:10 -0700 (PDT) From: Hsin-Yi Wang To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 2/3] fdt: add support for rng-seed Date: Mon, 20 May 2019 00:04:45 +0800 Message-Id: <20190519160446.320-2-hsinyi@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190519160446.320-1-hsinyi@chromium.org> References: <20190519160446.320-1-hsinyi@chromium.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190519_090512_231439_CB208B31 X-CRM114-Status: GOOD ( 15.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Yu Zhao , Kees Cook , Ard Biesheuvel , Catalin Marinas , Stephen Boyd , Will Deacon , linux-kernel@vger.kernel.org, Mike Rapoport , Jun Yao , Miles Chen , Rob Herring , James Morse , Hsin-Yi Wang , Andrew Murray , Andrew Morton , Laura Abbott , Frank Rowand , Robin Murphy Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Introducing a chosen node, rng-seed, which is an entropy that can be passed to kernel called very early to increase initial device randomness. Bootloader should provide this entropy and the value is read from /chosen/rng-seed in DT. Signed-off-by: Hsin-Yi Wang --- change log v2->v4: * v3 abandoned * fix doc error --- Documentation/devicetree/bindings/chosen.txt | 14 ++++++++++++++ drivers/of/fdt.c | 10 ++++++++++ 2 files changed, 24 insertions(+) diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index 45e79172a646..678e81bc4383 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -28,6 +28,20 @@ mode) when EFI_RNG_PROTOCOL is supported, it will be overwritten by the Linux EFI stub (which will populate the property itself, using EFI_RNG_PROTOCOL). +rng-seed +----------- + +This property serves as an entropy to add device randomness. It is parsed +as a byte array, e.g. + +/ { + chosen { + rng-seed = <0x31 0x95 0x1b 0x3c 0xc9 0xfa 0xb3 ...>; + }; +}; + +This random value should be provided by bootloader. + stdout-path ----------- diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index de893c9616a1..7f3d72921b23 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -24,6 +24,7 @@ #include #include #include +#include #include /* for COMMAND_LINE_SIZE */ #include @@ -1079,6 +1080,7 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, { int l; const char *p; + const void *rng_seed; pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname); @@ -1113,6 +1115,14 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, pr_debug("Command line is: %s\n", (char*)data); + rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l); + if (rng_seed && l > 0) { + add_device_randomness(rng_seed, l); + + /* try to clear seed so it won't be found. */ + fdt_delprop(initial_boot_params, node, "rng-seed"); + } + /* break now */ return 1; }