From patchwork Thu Sep 29 23:23:34 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 12994729 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EB3A4C433FE for ; Thu, 29 Sep 2022 23:25:48 +0000 (UTC) Received: from localhost ([::1]:46244 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oe2uZ-0006mo-Pi for qemu-devel@archiver.kernel.org; Thu, 29 Sep 2022 19:25:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40968) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oe2sp-0004q7-8U for qemu-devel@nongnu.org; Thu, 29 Sep 2022 19:23:59 -0400 Received: from ams.source.kernel.org ([145.40.68.75]:50434) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oe2sn-0008VD-Hd for qemu-devel@nongnu.org; Thu, 29 Sep 2022 19:23:58 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 31759B8267F; Thu, 29 Sep 2022 23:23:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D13EC433C1; Thu, 29 Sep 2022 23:23:52 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="PDjBpkXD" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1664493829; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=s4iMmrVnKX4fWtisVeaMk48H8te3Kjy/7gY9G+U0Yws=; b=PDjBpkXDpT3TzvY1RJUbLEqYU6B0N2jPyu6aXkuySZM6+tsjvKuL2VGi+iBmPXZB8gb7aj WGW0jdoNHEMgrdlRIKM6fsaCx+S2UwR2RsKjTAAbORhiRpkPbKjH6r/fqNTcyVI44TkgXe 4MHrifYxMApW0WftMQYiulvE/OPAM1E= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 94819b2a (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 29 Sep 2022 23:23:48 +0000 (UTC) From: "Jason A. Donenfeld" To: qemu-devel@nongnu.org, peter.maydell@linaro.org Cc: "Jason A. Donenfeld" , Alistair Francis , David Gibson Subject: [PATCH 1/6] device-tree: add re-randomization helper function Date: Fri, 30 Sep 2022 01:23:34 +0200 Message-Id: <20220929232339.372813-1-Jason@zx2c4.com> MIME-Version: 1.0 Received-SPF: pass client-ip=145.40.68.75; envelope-from=SRS0=kpRN=2A=zx2c4.com=Jason@kernel.org; helo=ams.source.kernel.org X-Spam_score_int: -67 X-Spam_score: -6.8 X-Spam_bar: ------ X-Spam_report: (-6.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.25, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" When the system reboots, the rng-seed that the FDT has should be re-randomized, so that the new boot gets a new seed. Several architectures require this functionality, so export a function for injecting a new seed into the given FDT. Cc: Alistair Francis Cc: David Gibson Signed-off-by: Jason A. Donenfeld Reviewed-by: Bin Meng --- include/sysemu/device_tree.h | 9 +++++++++ softmmu/device_tree.c | 21 +++++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h index ef060a9759..d552f324b6 100644 --- a/include/sysemu/device_tree.h +++ b/include/sysemu/device_tree.h @@ -196,6 +196,15 @@ int qemu_fdt_setprop_sized_cells_from_array(void *fdt, qdt_tmp); \ }) + +/** + * qemu_fdt_randomize_seeds: + * @fdt: device tree blob + * + * Re-randomize all "rng-seed" properties with new seeds. + */ +void qemu_fdt_randomize_seeds(void *fdt); + #define FDT_PCI_RANGE_RELOCATABLE 0x80000000 #define FDT_PCI_RANGE_PREFETCHABLE 0x40000000 #define FDT_PCI_RANGE_ALIASED 0x20000000 diff --git a/softmmu/device_tree.c b/softmmu/device_tree.c index 6ca3fad285..d986c7b7b3 100644 --- a/softmmu/device_tree.c +++ b/softmmu/device_tree.c @@ -22,6 +22,7 @@ #include "qemu/option.h" #include "qemu/bswap.h" #include "qemu/cutils.h" +#include "qemu/guest-random.h" #include "sysemu/device_tree.h" #include "hw/loader.h" #include "hw/boards.h" @@ -643,3 +644,23 @@ out: g_free(propcells); return ret; } + +void qemu_fdt_randomize_seeds(void *fdt) +{ + int noffset, poffset, len; + const char *name; + uint8_t *data; + + for (noffset = fdt_next_node(fdt, 0, NULL); + noffset >= 0; + noffset = fdt_next_node(fdt, noffset, NULL)) { + for (poffset = fdt_first_property_offset(fdt, noffset); + poffset >= 0; + poffset = fdt_next_property_offset(fdt, poffset)) { + data = (uint8_t *)fdt_getprop_by_offset(fdt, poffset, &name, &len); + if (!data || strcmp(name, "rng-seed")) + continue; + qemu_guest_getrandom_nofail(data, len); + } + } +}