From nobody Sat Feb 7 05:49:32 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1566317539; cv=none; d=zoho.com; s=zohoarc; b=UsmcOGjMj/5AJZlk+JU5OouYGUZ6RZotn3su3Pg1VkyYGQSJuFGYE2/q2wbWvzONmVrlrAQXeo/If2rraHhb31BX2zYuJ2MRm0G/ra5F9i1BuNKF2acCQWfBTgXmJH61BBtKVXyMQ7yhzM7L8a1BwxBZM5ReU4PpCu1UiU+cSao= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1566317539; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=kSqQczDHV0mNJ668vrzz9ceGsM/0WRapa2gtCV0EhSM=; b=Vd1tIjNg+fwwH9TYFE4ZSk/TJtyDWpXDvuniim+jn3Fmn/K2Hi1bCMtCpkq00v30tyFOwklPF5SckNIJTX/rSMOfaWFCl6w7L7PMtlSVjX87pzeYAZzCdGYiURsSNHKYLjt1ZNpdOKnp2kpdpJjtaGra7jqlKHjXAyEVJiBvVYI= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1566317539193877.8214916865137; Tue, 20 Aug 2019 09:12:19 -0700 (PDT) Received: from localhost ([::1]:39378 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i06k6-0008LE-4W for importer@patchew.org; Tue, 20 Aug 2019 12:12:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42138) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i06eQ-0000QI-4V for qemu-devel@nongnu.org; Tue, 20 Aug 2019 12:06:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i06eO-0002Vo-SO for qemu-devel@nongnu.org; Tue, 20 Aug 2019 12:06:25 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57978) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i06eO-0002VG-LC for qemu-devel@nongnu.org; Tue, 20 Aug 2019 12:06:24 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 01D2969099; Tue, 20 Aug 2019 16:06:24 +0000 (UTC) Received: from thinkpad.redhat.com (ovpn-117-179.ams2.redhat.com [10.36.117.179]) by smtp.corp.redhat.com (Postfix) with ESMTP id CEB7087A1; Tue, 20 Aug 2019 16:06:21 +0000 (UTC) From: Laurent Vivier To: qemu-devel@nongnu.org Date: Tue, 20 Aug 2019 18:06:13 +0200 Message-Id: <20190820160615.14616-2-lvivier@redhat.com> In-Reply-To: <20190820160615.14616-1-lvivier@redhat.com> References: <20190820160615.14616-1-lvivier@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 20 Aug 2019 16:06:24 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v8 1/3] rng-builtin: add an RNG backend that uses qemu_guest_getrandom() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= , Kashyap Chamarthy , Amit Shah , Richard Henderson , "Richard W . M . Jones" , Markus Armbruster , "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" Add a new RNG backend using QEMU builtin getrandom function. It can be created and used with something like: ... -object rng-builtin,id=3Drng0 -device virtio-rng,rng=3Drng0 ... Signed-off-by: Laurent Vivier --- backends/Makefile.objs | 2 +- backends/rng-builtin.c | 78 ++++++++++++++++++++++++++++++++++++++++++ qemu-options.hx | 7 ++++ 3 files changed, 86 insertions(+), 1 deletion(-) create mode 100644 backends/rng-builtin.c diff --git a/backends/Makefile.objs b/backends/Makefile.objs index 981e8e122f2c..f0691116e86e 100644 --- a/backends/Makefile.objs +++ b/backends/Makefile.objs @@ -1,4 +1,4 @@ -common-obj-y +=3D rng.o rng-egd.o +common-obj-y +=3D rng.o rng-egd.o rng-builtin.o common-obj-$(CONFIG_POSIX) +=3D rng-random.o =20 common-obj-$(CONFIG_TPM) +=3D tpm.o diff --git a/backends/rng-builtin.c b/backends/rng-builtin.c new file mode 100644 index 000000000000..3381d47174df --- /dev/null +++ b/backends/rng-builtin.c @@ -0,0 +1,78 @@ +/* + * QEMU Builtin Random Number Generator Backend + * + * This work is licensed under the terms of the GNU GPL, version 2 or late= r. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include "sysemu/rng.h" +#include "qemu/main-loop.h" +#include "qemu/guest-random.h" + +#define TYPE_RNG_BUILTIN "rng-builtin" +#define RNG_BUILTIN(obj) OBJECT_CHECK(RngBuiltin, (obj), TYPE_RNG_BUILTIN) + +typedef struct RngBuiltin { + RngBackend parent; + QEMUBH *bh; +} RngBuiltin; + +static void rng_builtin_receive_entropy_bh(void *opaque) +{ + RngBuiltin *s =3D opaque; + + while (!QSIMPLEQ_EMPTY(&s->parent.requests)) { + RngRequest *req =3D QSIMPLEQ_FIRST(&s->parent.requests); + + qemu_guest_getrandom_nofail(req->data, req->size); + + req->receive_entropy(req->opaque, req->data, req->size); + + rng_backend_finalize_request(&s->parent, req); + } +} + +static void rng_builtin_request_entropy(RngBackend *b, RngRequest *req) +{ + RngBuiltin *s =3D RNG_BUILTIN(b); + + qemu_bh_schedule(s->bh); +} + +static void rng_builtin_init(Object *obj) +{ + RngBuiltin *s =3D RNG_BUILTIN(obj); + + s->bh =3D qemu_bh_new(rng_builtin_receive_entropy_bh, s); +} + +static void rng_builtin_finalize(Object *obj) +{ + RngBuiltin *s =3D RNG_BUILTIN(obj); + + qemu_bh_delete(s->bh); +} + +static void rng_builtin_class_init(ObjectClass *klass, void *data) +{ + RngBackendClass *rbc =3D RNG_BACKEND_CLASS(klass); + + rbc->request_entropy =3D rng_builtin_request_entropy; +} + +static const TypeInfo rng_builtin_info =3D { + .name =3D TYPE_RNG_BUILTIN, + .parent =3D TYPE_RNG_BACKEND, + .instance_size =3D sizeof(RngBuiltin), + .instance_init =3D rng_builtin_init, + .instance_finalize =3D rng_builtin_finalize, + .class_init =3D rng_builtin_class_init, +}; + +static void register_types(void) +{ + type_register_static(&rng_builtin_info); +} + +type_init(register_types); diff --git a/qemu-options.hx b/qemu-options.hx index 9621e934c0bf..312586cc18f8 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4323,6 +4323,13 @@ other options. =20 The @option{share} boolean option is @var{on} by default with memfd. =20 +@item -object rng-builtin,id=3D@var{id} + +Creates a random number generator backend which obtains entropy from +QEMU builtin functions. The @option{id} parameter is a unique ID that +will be used to reference this entropy backend from the @option{virtio-rng} +device. + @item -object rng-random,id=3D@var{id},filename=3D@var{/dev/random} =20 Creates a random number generator backend which obtains entropy from --=20 2.21.0