From patchwork Fri Oct 14 02:16:48 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: 13006594 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 719AFC43217 for ; Fri, 14 Oct 2022 02:21:01 +0000 (UTC) Received: from localhost ([::1]:34312 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ojAJo-0000Hk-Hs for qemu-devel@archiver.kernel.org; Thu, 13 Oct 2022 22:21:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41592) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ojAG5-0000Nr-2v for qemu-devel@nongnu.org; Thu, 13 Oct 2022 22:17:09 -0400 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]:39724) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ojAG3-0001fb-Ej for qemu-devel@nongnu.org; Thu, 13 Oct 2022 22:17:08 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 8EBF6619C0; Fri, 14 Oct 2022 02:17:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 46520C433C1; Fri, 14 Oct 2022 02:17:05 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="etPOn/YE" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1665713823; 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: in-reply-to:in-reply-to:references:references; bh=s4iMmrVnKX4fWtisVeaMk48H8te3Kjy/7gY9G+U0Yws=; b=etPOn/YEhrs2IAt0ab+GMLFtY6dbhfQ2OrVDQXzsoi+V6X/ml1T9CeyQk+cigNcppPgAm4 q5bh1Z7rp+A2tf4df7IQcGb6frQe+KKOOKiEdhBumzYlq11f3nFzA6PWplxlZAF6Zv47IS cPDj2C1BVyEj2qPqUWaNyscJTnVIuic= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 8636cc58 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Fri, 14 Oct 2022 02:17:03 +0000 (UTC) From: "Jason A. Donenfeld" To: peter.maydell@linaro.org, pbonzini@redhat.com, qemu-devel@nongnu.org, richard.henderson@linaro.org Cc: "Jason A. Donenfeld" , Alistair Francis , David Gibson Subject: [PATCH v3 3/8] device-tree: add re-randomization helper function Date: Thu, 13 Oct 2022 20:16:48 -0600 Message-Id: <20221014021653.1461512-4-Jason@zx2c4.com> In-Reply-To: <20221014021653.1461512-1-Jason@zx2c4.com> References: <20221014021653.1461512-1-Jason@zx2c4.com> MIME-Version: 1.0 Received-SPF: pass client-ip=2604:1380:4641:c500::1; envelope-from=SRS0=NTzD=2P=zx2c4.com=Jason@kernel.org; helo=dfw.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 --- 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); + } + } +}