From patchwork Wed Aug 19 05:46:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Gerd Hoffmann X-Patchwork-Id: 276084 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B73C2C433E1 for ; Wed, 19 Aug 2020 05:57:19 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 826F920772 for ; Wed, 19 Aug 2020 05:57:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cxLMqOux" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 826F920772 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:48928 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k8H66-0006ar-RZ for qemu-devel@archiver.kernel.org; Wed, 19 Aug 2020 01:57:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50310) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k8GwQ-0007lN-QZ for qemu-devel@nongnu.org; Wed, 19 Aug 2020 01:47:18 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:55289 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1k8GwH-0006iA-NZ for qemu-devel@nongnu.org; Wed, 19 Aug 2020 01:47:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1597816016; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RBGqP8EFZYGK8U5Mb1X88W+B9neqleFAVo0mDjdtZo8=; b=cxLMqOuxzBDAdogliKegtrmT7rH4FVaQp2rMHRbabnaLIA/Q50PzY7nbWgrV7rAgtZG/sb 3hg1NtopjV8kqIjuwXYJVcTXSsYVwWC0mT7zRI663+4uFtkx4M8CNB/XLs0hfoRFf3esIC lpxsT9SPJ1U/RY1W0EYWoNJrPEAlPIY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-337-EzwyMOUoN7uiaF0kxollQw-1; Wed, 19 Aug 2020 01:46:54 -0400 X-MC-Unique: EzwyMOUoN7uiaF0kxollQw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1BB7A801ADD; Wed, 19 Aug 2020 05:46:53 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-112-195.ams2.redhat.com [10.36.112.195]) by smtp.corp.redhat.com (Postfix) with ESMTP id DF4C57A1FA; Wed, 19 Aug 2020 05:46:48 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 87F5B1FCE8; Wed, 19 Aug 2020 07:46:44 +0200 (CEST) From: Gerd Hoffmann To: qemu-devel@nongnu.org Subject: [PULL 06/17] docs: Add USB U2F key device documentation Date: Wed, 19 Aug 2020 07:46:33 +0200 Message-Id: <20200819054644.30610-7-kraxel@redhat.com> In-Reply-To: <20200819054644.30610-1-kraxel@redhat.com> References: <20200819054644.30610-1-kraxel@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kraxel@redhat.com X-Mimecast-Spam-Score: 0.001 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=kraxel@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/18 22:38:38 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , =?utf-8?q?C=C3=A9sar_Belley?= , Gerd Hoffmann , Cleber Rosa , Paolo Bonzini , Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: César Belley Add USB U2F key device documentation: - USB U2F key device - Building - Using u2f-emulated - Using u2f-passthru - Libu2f-emu Signed-off-by: César Belley Message-id: 20200812094135.20550-3-cesar.belley@lse.epita.fr Signed-off-by: Gerd Hoffmann --- docs/u2f.txt | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 docs/u2f.txt diff --git a/docs/u2f.txt b/docs/u2f.txt new file mode 100644 index 000000000000..f60052882ec3 --- /dev/null +++ b/docs/u2f.txt @@ -0,0 +1,101 @@ +QEMU U2F Key Device Documentation. + +Contents +1. USB U2F key device +2. Building +3. Using u2f-emulated +4. Using u2f-passthru +5. Libu2f-emu + +1. USB U2F key device + +U2F is an open authentication standard that enables relying parties +exposed to the internet to offer a strong second factor option for end +user authentication. + +The standard brings many advantages to both parties, client and server, +allowing to reduce over-reliance on passwords, it increases authentication +security and simplifies passwords. + +The second factor is materialized by a device implementing the U2F +protocol. In case of a USB U2F security key, it is a USB HID device +that implements the U2F protocol. + +In Qemu, the USB U2F key device offers a dedicated support of U2F, allowing +guest USB FIDO/U2F security keys operating in two possible modes: +pass-through and emulated. + +The pass-through mode consists of passing all requests made from the guest +to the physical security key connected to the host machine and vice versa. +In addition, the dedicated pass-through allows to have a U2F security key +shared on several guests which is not possible with a simple host device +assignment pass-through. + +The emulated mode consists of completely emulating the behavior of an +U2F device through software part. Libu2f-emu is used for that. + + +2. Building + +To ensure the build of the u2f-emulated device variant which depends +on libu2f-emu: configuring and building: + + ./configure --enable-u2f && make + + +3. Using u2f-emulated + +To work, an emulated U2F device must have four elements: + * ec x509 certificate + * ec private key + * counter (four bytes value) + * 48 bytes of entropy (random bits) + +To use this type of device, this one has to be configured, and these +four elements must be passed one way or another. + +Assuming that you have a working libu2f-emu installed on the host. +There are three possible ways of configurations: + * ephemeral + * setup directory + * manual + +Ephemeral is the simplest way to configure, it lets the device generate +all the elements it needs for a single use of the lifetime of the device. + + qemu -usb -device u2f-emulated + +Setup directory allows to configure the device from a directory containing +four files: + * certificate.pem: ec x509 certificate + * private-key.pem: ec private key + * counter: counter value + * entropy: 48 bytes of entropy + + qemu -usb -device u2f-emulated,dir=$dir + +Manual allows to configure the device more finely by specifying each +of the elements necessary for the device: + * cert + * priv + * counter + * entropy + + qemu -usb -device u2f-emulated,cert=$DIR1/$FILE1,priv=$DIR2/$FILE2,counter=$DIR3/$FILE3,entropy=$DIR4/$FILE4 + + +4. Using u2f-passthru + +On the host specify the u2f-passthru device with a suitable hidraw: + + qemu -usb -device u2f-passthru,hidraw=/dev/hidraw0 + + +5. Libu2f-emu + +The u2f-emulated device uses libu2f-emu for the U2F key emulation. Libu2f-emu +implements completely the U2F protocol device part for all specified +transport given by the FIDO Alliance. + +For more information about libu2f-emu see this page: +https://github.com/MattGorko/libu2f-emu.