From nobody Thu Nov 6 03:22:10 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; envelope-from=libvir-list-bounces@redhat.com; helo=mx1.redhat.com; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mx.zohomail.com with SMTPS id 1539091478085545.9961752821865; Tue, 9 Oct 2018 06:24:38 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CCB9230DF710; Tue, 9 Oct 2018 13:24:36 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 940A2798CA; Tue, 9 Oct 2018 13:24:36 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 4EBF04CAA0; Tue, 9 Oct 2018 13:24:36 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id w99DOZW2002706 for ; Tue, 9 Oct 2018 09:24:35 -0400 Received: by smtp.corp.redhat.com (Postfix) id 3C0196A96E; Tue, 9 Oct 2018 13:24:35 +0000 (UTC) Received: from localhost.localdomain.com (unknown [10.42.22.189]) by smtp.corp.redhat.com (Postfix) with ESMTP id 105E66A03C; Tue, 9 Oct 2018 13:24:20 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Date: Tue, 9 Oct 2018 14:23:29 +0100 Message-Id: <20181009132330.7549-6-berrange@redhat.com> In-Reply-To: <20181009132330.7549-1-berrange@redhat.com> References: <20181009132330.7549-1-berrange@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-loop: libvir-list@redhat.com Cc: Kevin Wolf , qemu-block@nongnu.org, Juan Quintela , libvir-list@redhat.com, Max Reitz , Gerd Hoffmann , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Paolo Bonzini , "Dr. David Alan Gilbert" Subject: [libvirt] [PATCH v3 5/6] vnc: allow specifying a custom authorization object name X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Tue, 09 Oct 2018 13:24:37 +0000 (UTC) X-ZohoMail: RDMRC_0 RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" From: "Daniel P. Berrange" The VNC server has historically had support for ACLs to check both the SASL username and the TLS x509 distinguished name. The VNC server was responsible for creating the initial ACL, and the client app was then responsible for populating it with rules using the HMP 'acl_add' command. This is not satisfactory for a variety of reasons. There is no way to populate the ACLs from the command line, users are forced to use the HMP. With multiple network services all supporting TLS and ACLs now, it is desirable to be able to define a single ACL that is referenced by all services. To address these limitations, two new options are added to the VNC server CLI. The 'tls-authz' option takes the ID of a QAuthZ object to use for checking TLS x509 distinguished names, and the 'sasl-authz' option takes the ID of another object to use for checking SASL usernames. In this example, we setup two authorization rules. The first allows any client with a certificate issued by the 'RedHat' organization in the 'London' locality. The second ACL allows clients with either the 'joe@REDHAT.COM' or 'fred@REDHAT.COM' kerberos usernames. Both checks must pass for the user to be allowed. $QEMU -object tls-creds-x509,id=3Dtls0,dir=3D/home/berrange/qemutls,\ endpoint=3Dserver,verify-peer=3Dyes \ -object authz-simple,id=3Dauthz0,policy=3Ddeny,\ rules.0.match=3DO=3DRedHat,,L=3DLondon,rules.0.policy=3Da= llow \ -object authz-simple,id=3Dauthz1,policy=3Ddeny,\ rules.0.match=3Dfred@REDHAT.COM,rules.0.policy=3Dallow \ rules.0.match=3Djoe@REDHAT.COM,rules.0.policy=3Dallow \ -vnc 0.0.0.0:1,tls-creds=3Dtls0,tls-authz=3Dauthz0, sasl,sasl-authz=3Dauthz1 \ ...other QEMU args... Signed-off-by: Daniel P. Berrange Reviewed-by: Juan Quintela --- qemu-deprecated.texi | 5 ++++ qemu-options.hx | 35 ++++++++++++++++++-------- ui/vnc.c | 58 +++++++++++++++++++++++++++++++++++++------- 3 files changed, 79 insertions(+), 19 deletions(-) diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi index 16ff946b55..d74d9ea02c 100644 --- a/qemu-deprecated.texi +++ b/qemu-deprecated.texi @@ -93,6 +93,11 @@ for these file types is 'host_cdrom' or 'host_device' as= appropriate. The @option{name} parameter of the @option{-net} option is a synonym for the @option{id} parameter, which should now be used instead. =20 +@subsection -vnc acl (since 3.1.0) + +The @code{acl} option to the @code{-vnc} argument has been replaced +by the @code{tls-authz} and @code{sasl-authz} options. + @section QEMU Machine Protocol (QMP) commands =20 @subsection block-dirty-bitmap-add "autoload" parameter (since 2.12.0) diff --git a/qemu-options.hx b/qemu-options.hx index 5079074088..6c3eef8b32 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -1626,6 +1626,14 @@ will cause the VNC server socket to enable the VeNCr= ypt auth mechanism. The credentials should have been previously created using the @option{-object tls-creds} argument. =20 +@item tls-authz=3D@var{ID} + +Provides the ID of the QAuthZ authorization object against which +the client's x509 distinguished name will validated. This object is +only resolved at time of use, so can be deleted and recreated on the +fly while the VNC server is active. If missing, it will default +to denying access. + @item sasl =20 Require that the client use SASL to authenticate with the VNC server. @@ -1641,18 +1649,25 @@ ensures a data encryption preventing compromise of = authentication credentials. See the @ref{vnc_security} section for details on using SASL authentication. =20 +@item sasl-authz=3D@var{ID} + +Provides the ID of the QAuthZ authorization object against which +the client's SASL username will validated. This object is +only resolved at time of use, so can be deleted and recreated on the +fly while the VNC server is active. If missing, it will default +to denying access. + @item acl =20 -Turn on access control lists for checking of the x509 client certificate -and SASL party. For x509 certs, the ACL check is made against the -certificate's distinguished name. This is something that looks like -@code{C=3DGB,O=3DACME,L=3DBoston,CN=3Dbob}. For SASL party, the ACL check = is -made against the username, which depending on the SASL plugin, may -include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. -When the @option{acl} flag is set, the initial access list will be -empty, with a @code{deny} policy. Thus no one will be allowed to -use the VNC server until the ACLs have been loaded. This can be -achieved using the @code{acl} monitor command. +Legacy method for enabling authorization of clients against the +x509 distinguished name and SASL username. It results in the creation +of two @code{authz-list} objects with IDs of @code{vnc.username} and +@code{vnc.x509dname}. The rules for these objects must be configured +with the HMP ACL commands. + +This option is deprecated and should no longer be used. The new +@option{sasl-authz} and @option{tls-authz} options are a +replacement. =20 @item lossy =20 diff --git a/ui/vnc.c b/ui/vnc.c index 60cb7c2d3d..8624b10e48 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -3395,6 +3395,12 @@ static QemuOptsList qemu_vnc_opts =3D { },{ .name =3D "acl", .type =3D QEMU_OPT_BOOL, + },{ + .name =3D "tls-authz", + .type =3D QEMU_OPT_STRING, + },{ + .name =3D "sasl-authz", + .type =3D QEMU_OPT_STRING, },{ .name =3D "lossy", .type =3D QEMU_OPT_BOOL, @@ -3834,6 +3840,8 @@ void vnc_display_open(const char *id, Error **errp) const char *credid; bool sasl =3D false; int acl =3D 0; + const char *tlsauthz; + const char *saslauthz; int lock_key_sync =3D 1; int key_delay_ms; =20 @@ -3905,7 +3913,33 @@ void vnc_display_open(const char *id, Error **errp) goto fail; } } + if (qemu_opt_get(opts, "acl")) { + error_report("The 'acl' option to -vnc is deprecated. " + "Please use the 'tls-authz' and 'sasl-authz' " + "options instead"); + } acl =3D qemu_opt_get_bool(opts, "acl", false); + tlsauthz =3D qemu_opt_get(opts, "tls-authz"); + if (acl && tlsauthz) { + error_setg(errp, "'acl' option is mutually exclusive with the " + "'tls-authz' option"); + goto fail; + } + if (tlsauthz && !vd->tlscreds) { + error_setg(errp, "'tls-authz' provided but TLS is not enabled"); + goto fail; + } + + saslauthz =3D qemu_opt_get(opts, "sasl-authz"); + if (acl && saslauthz) { + error_setg(errp, "'acl' option is mutually exclusive with the " + "'sasl-authz' option"); + goto fail; + } + if (saslauthz && !sasl) { + error_setg(errp, "'sasl-authz' provided but SASL auth is not enabl= ed"); + goto fail; + } =20 share =3D qemu_opt_get(opts, "share"); if (share) { @@ -3935,7 +3969,9 @@ void vnc_display_open(const char *id, Error **errp) vd->non_adaptive =3D true; } =20 - if (acl) { + if (tlsauthz) { + vd->tlsauthzid =3D g_strdup(tlsauthz); + } else if (acl) { if (strcmp(vd->id, "default") =3D=3D 0) { vd->tlsauthzid =3D g_strdup("vnc.x509dname"); } else { @@ -3946,15 +3982,19 @@ void vnc_display_open(const char *id, Error **errp) &error_abort)); } #ifdef CONFIG_VNC_SASL - if (acl && sasl) { - if (strcmp(vd->id, "default") =3D=3D 0) { - vd->sasl.authzid =3D g_strdup("vnc.username"); - } else { - vd->sasl.authzid =3D g_strdup_printf("vnc.%s.username", vd->id= ); + if (sasl) { + if (saslauthz) { + vd->sasl.authzid =3D g_strdup(saslauthz); + } else if (acl) { + if (strcmp(vd->id, "default") =3D=3D 0) { + vd->sasl.authzid =3D g_strdup("vnc.username"); + } else { + vd->sasl.authzid =3D g_strdup_printf("vnc.%s.username", vd= ->id); + } + vd->sasl.authz =3D QAUTHZ(qauthz_list_new(vd->sasl.authzid, + QAUTHZ_LIST_POLICY_DEN= Y, + &error_abort)); } - vd->sasl.authz =3D QAUTHZ(qauthz_list_new(vd->sasl.authzid, - QAUTHZ_LIST_POLICY_DENY, - &error_abort)); } #endif =20 --=20 2.17.1 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list