From patchwork Fri Feb 15 17:14:34 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 10815609 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4A784922 for ; Fri, 15 Feb 2019 17:33:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3770F2FCF6 for ; Fri, 15 Feb 2019 17:33:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2BB732FCFE; Fri, 15 Feb 2019 17:33:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 7E5E62FCF6 for ; Fri, 15 Feb 2019 17:33:27 +0000 (UTC) Received: from localhost ([127.0.0.1]:43863 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1guhMc-0000wf-Sp for patchwork-qemu-devel@patchwork.kernel.org; Fri, 15 Feb 2019 12:33:26 -0500 Received: from eggs.gnu.org ([209.51.188.92]:37156) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1guh5l-0005Sn-QZ for qemu-devel@nongnu.org; Fri, 15 Feb 2019 12:16:04 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1guh5k-0006bH-DW for qemu-devel@nongnu.org; Fri, 15 Feb 2019 12:16:01 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57424) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1guh5h-0006TQ-93; Fri, 15 Feb 2019 12:15:57 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id EE9E1C0467E4; Fri, 15 Feb 2019 17:15:48 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-112-65.ams2.redhat.com [10.36.112.65]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0FA6F60C69; Fri, 15 Feb 2019 17:15:44 +0000 (UTC) From: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= To: qemu-devel@nongnu.org Date: Fri, 15 Feb 2019 17:14:34 +0000 Message-Id: <20190215171436.30457-5-berrange@redhat.com> In-Reply-To: <20190215171436.30457-1-berrange@redhat.com> References: <20190215171436.30457-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Fri, 15 Feb 2019 17:15:49 +0000 (UTC) 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 v4 4/6] chardev: add support for authorization for TLS clients X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , qemu-block@nongnu.org, Juan Quintela , libvir-list@redhat.com, Markus Armbruster , Max Reitz , Gerd Hoffmann , Paolo Bonzini , =?utf-8?q?Marc-Andr=C3=A9_Lureau?= , "Dr. David Alan Gilbert" Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: "Daniel P. Berrange" Currently any client which can complete the TLS handshake is able to use a chardev server. The server admin can turn on the 'verify-peer' option for the x509 creds to require the client to provide a x509 certificate. This means the client will have to acquire a certificate from the CA before they are permitted to use the chardev server. This is still a fairly low bar. This adds a 'tls-authz=OBJECT-ID' option to the socket chardev backend which takes the ID of a previously added 'QAuthZ' object instance. This will be used to validate the client's x509 distinguished name. Clients failing the check will not be permitted to use the chardev server. For example to setup authorization that only allows connection from a client whose x509 certificate distinguished name contains 'CN=fred', you would use: $QEMU -object tls-creds-x509,id=tls0,dir=/home/berrange/qemutls,\ endpoint=server,verify-peer=yes \ -object authz-simple,id=authz0,identity=CN=laptop.example.com,,\ O=Example Org,,L=London,,ST=London,,C=GB \ -chardev socket,host=127.0.0.1,port=9000,server,\ tls-creds=tls0,tls-authz=authz0 \ ...other qemu args... Reviewed-by: Juan Quintela Signed-off-by: Daniel P. Berrange --- chardev/char-socket.c | 12 +++++++++++- chardev/char.c | 3 +++ qapi/char.json | 6 ++++++ qemu-options.hx | 9 +++++++-- 4 files changed, 27 insertions(+), 3 deletions(-) diff --git a/chardev/char-socket.c b/chardev/char-socket.c index 4fcdd8aedd..e4c8ba5798 100644 --- a/chardev/char-socket.c +++ b/chardev/char-socket.c @@ -59,6 +59,7 @@ typedef struct { QIONetListener *listener; GSource *hup_source; QCryptoTLSCreds *tls_creds; + char *tls_authz; TCPChardevState state; int max_size; int do_telnetopt; @@ -807,7 +808,7 @@ static void tcp_chr_tls_init(Chardev *chr) if (s->is_listen) { tioc = qio_channel_tls_new_server( s->ioc, s->tls_creds, - NULL, /* XXX Use an ACL */ + s->tls_authz, &err); } else { tioc = qio_channel_tls_new_client( @@ -1055,6 +1056,7 @@ static void char_socket_finalize(Object *obj) if (s->tls_creds) { object_unref(OBJECT(s->tls_creds)); } + g_free(s->tls_authz); qemu_chr_be_event(chr, CHR_EVENT_CLOSED); } @@ -1320,6 +1322,7 @@ static void qmp_chardev_open_socket(Chardev *chr, } } } + s->tls_authz = g_strdup(sock->tls_authz); s->addr = addr = socket_address_flatten(sock->addr); @@ -1358,6 +1361,7 @@ static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend, const char *port = qemu_opt_get(opts, "port"); const char *fd = qemu_opt_get(opts, "fd"); SocketAddressLegacy *addr; + const char *tls_authz = qemu_opt_get(opts, "tls-authz"); ChardevSocket *sock; if ((!!path + !!fd + !!host) != 1) { @@ -1370,6 +1374,10 @@ static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend, error_setg(errp, "chardev: socket: no port given"); return; } + if (tls_authz && !tls_creds) { + error_setg(errp, "Authorization can only be used when TLS is enabled"); + return; + } backend->type = CHARDEV_BACKEND_KIND_SOCKET; sock = backend->u.socket.data = g_new0(ChardevSocket, 1); @@ -1399,6 +1407,8 @@ static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend, sock->reconnect = qemu_opt_get_number(opts, "reconnect", 0); sock->has_tls_creds = qemu_opt_get(opts, "tls-creds"); sock->tls_creds = g_strdup(qemu_opt_get(opts, "tls-creds")); + sock->has_tls_authz = qemu_opt_get(opts, "tls-authz"); + sock->tls_authz = g_strdup(qemu_opt_get(opts, "tls-authz")); addr = g_new0(SocketAddressLegacy, 1); if (path) { diff --git a/chardev/char.c b/chardev/char.c index f6d61fa5f8..514cd6b0c3 100644 --- a/chardev/char.c +++ b/chardev/char.c @@ -880,6 +880,9 @@ QemuOptsList qemu_chardev_opts = { },{ .name = "tls-creds", .type = QEMU_OPT_STRING, + },{ + .name = "tls-authz", + .type = QEMU_OPT_STRING, },{ .name = "websocket", .type = QEMU_OPT_BOOL, diff --git a/qapi/char.json b/qapi/char.json index 77ed847972..7847c98d05 100644 --- a/qapi/char.json +++ b/qapi/char.json @@ -248,6 +248,11 @@ # @addr: socket address to listen on (server=true) # or connect to (server=false) # @tls-creds: the ID of the TLS credentials object (since 2.6) +# @tls-authz: 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 chardev server is active. +# If missing, it will default to denying access (since 4.0) # @server: create server socket (default: true) # @wait: wait for incoming connection on server # sockets (default: false). @@ -268,6 +273,7 @@ { 'struct': 'ChardevSocket', 'data': { 'addr': 'SocketAddressLegacy', '*tls-creds': 'str', + '*tls-authz' : 'str', '*server': 'bool', '*wait': 'bool', '*nodelay': 'bool', diff --git a/qemu-options.hx b/qemu-options.hx index 22cfb32489..2bbcc743a4 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -2408,7 +2408,7 @@ DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" " [,server][,nowait][,telnet][,websocket][,reconnect=seconds][,mux=on|off]\n" - " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" + " [,logfile=PATH][,logappend=on|off][,tls-creds=ID][,tls-authz=ID] (tcp)\n" "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,websocket][,reconnect=seconds]\n" " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" @@ -2537,7 +2537,7 @@ The available backends are: A void device. This device will not emit any data, and will drop any data it receives. The null backend does not take any options. -@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,websocket][,reconnect=@var{seconds}][,tls-creds=@var{id}] +@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,websocket][,reconnect=@var{seconds}][,tls-creds=@var{id}][,tls-authz=@var{id}] Create a two-way stream socket, which can be either a TCP or a unix socket. A unix socket will be created if @option{path} is specified. Behaviour is @@ -2563,6 +2563,11 @@ and specifies the id of the TLS credentials to use for the handshake. The credentials must be previously created with the @option{-object tls-creds} argument. +@option{tls-auth} 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 +chardev server is active. If missing, it will default to denying access. + TCP and unix socket options are given below: @table @option