* [Qemu-devel] [PULL 1/4] qemu-nbd: add support for authorization of TLS clients
2019-03-08 17:39 [Qemu-devel] [PULL 0/4] NBD patches for 2019-03-08, 4.0 softfreeze Eric Blake
@ 2019-03-08 17:39 ` Eric Blake
2019-03-08 17:39 ` [Qemu-devel] [PULL 2/4] nbd: allow authorization with nbd-server-start QMP command Eric Blake
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Eric Blake @ 2019-03-08 17:39 UTC (permalink / raw)
To: qemu-devel
Cc: Daniel P. Berrange, Juan Quintela, Kevin Wolf, Max Reitz,
open list:Network Block Dev...
From: "Daniel P. Berrange" <berrange@redhat.com>
Currently any client which can complete the TLS handshake is able to use
the NBD 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 NBD server. This is still a fairly
low bar to cross.
This adds a '--tls-authz OBJECT-ID' option to the qemu-nbd command 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 authorization check will not be permitted to use the NBD
server.
For example to setup authorization that only allows connection from a client
whose x509 certificate distinguished name is
CN=laptop.example.com,O=Example Org,L=London,ST=London,C=GB
escape the commas in the name and use:
qemu-nbd --object tls-creds-x509,id=tls0,dir=/home/berrange/qemutls,\
endpoint=server,verify-peer=yes \
--object 'authz-simple,id=auth0,identity=CN=laptop.example.com,,\
O=Example Org,,L=London,,ST=London,,C=GB' \
--tls-creds tls0 \
--tls-authz authz0 \
....other qemu-nbd args...
NB: a real shell command line would not have leading whitespace after
the line continuation, it is just included here for clarity.
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20190227162035.18543-2-berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: split long line in --help text, tweak 233 to show that whitespace
after ,, in identity= portion is actually okay]
Signed-off-by: Eric Blake <eblake@redhat.com>
---
qemu-nbd.texi | 11 +++++++++--
include/block/nbd.h | 2 +-
nbd/server.c | 10 +++++-----
qemu-nbd.c | 19 ++++++++++++++++++-
tests/qemu-iotests/233 | 32 +++++++++++++++++++++++++++++---
tests/qemu-iotests/233.out | 11 +++++++++++
6 files changed, 73 insertions(+), 12 deletions(-)
diff --git a/qemu-nbd.texi b/qemu-nbd.texi
index d0c51828149..de342c76b87 100644
--- a/qemu-nbd.texi
+++ b/qemu-nbd.texi
@@ -117,6 +117,10 @@ option; or provide the credentials needed for connecting as a client
in list mode.
@item --fork
Fork off the server process and exit the parent once the server is running.
+@item --tls-authz=ID
+Specify the ID of a qauthz object previously created with the
+--object option. This will be used to authorize connecting users
+against their x509 distinguished name.
@item -v, --verbose
Display extra debugging information.
@item -h, --help
@@ -142,13 +146,16 @@ qemu-nbd -f qcow2 file.qcow2
@end example
Start a long-running server listening with encryption on port 10810,
-and require clients to have a correct X.509 certificate to connect to
+and whitelist clients with a specific X.509 certificate to connect to
a 1 megabyte subset of a raw file, using the export name 'subset':
@example
qemu-nbd \
--object tls-creds-x509,id=tls0,endpoint=server,dir=/path/to/qemutls \
- --tls-creds tls0 -t -x subset -p 10810 \
+ --object 'authz-simple,id=auth0,identity=CN=laptop.example.com,,\
+ O=Example Org,,L=London,,ST=London,,C=GB' \
+ --tls-creds tls0 --tls-authz auth0 \
+ -t -x subset -p 10810 \
--image-opts driver=raw,offset=1M,size=1M,file.driver=file,file.filename=file.raw
@end example
diff --git a/include/block/nbd.h b/include/block/nbd.h
index c6ef1ef42e8..b742ec4a89b 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -326,7 +326,7 @@ void nbd_export_close_all(void);
void nbd_client_new(QIOChannelSocket *sioc,
QCryptoTLSCreds *tlscreds,
- const char *tlsaclname,
+ const char *tlsauthz,
void (*close_fn)(NBDClient *, bool));
void nbd_client_get(NBDClient *client);
void nbd_client_put(NBDClient *client);
diff --git a/nbd/server.c b/nbd/server.c
index 0910d09a6d4..8ddfd3e3198 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -111,7 +111,7 @@ struct NBDClient {
NBDExport *exp;
QCryptoTLSCreds *tlscreds;
- char *tlsaclname;
+ char *tlsauthz;
QIOChannelSocket *sioc; /* The underlying data channel */
QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */
@@ -686,7 +686,7 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client,
tioc = qio_channel_tls_new_server(ioc,
client->tlscreds,
- client->tlsaclname,
+ client->tlsauthz,
errp);
if (!tioc) {
return NULL;
@@ -1348,7 +1348,7 @@ void nbd_client_put(NBDClient *client)
if (client->tlscreds) {
object_unref(OBJECT(client->tlscreds));
}
- g_free(client->tlsaclname);
+ g_free(client->tlsauthz);
if (client->exp) {
QTAILQ_REMOVE(&client->exp->clients, client, next);
nbd_export_put(client->exp);
@@ -2425,7 +2425,7 @@ static coroutine_fn void nbd_co_client_start(void *opaque)
*/
void nbd_client_new(QIOChannelSocket *sioc,
QCryptoTLSCreds *tlscreds,
- const char *tlsaclname,
+ const char *tlsauthz,
void (*close_fn)(NBDClient *, bool))
{
NBDClient *client;
@@ -2437,7 +2437,7 @@ void nbd_client_new(QIOChannelSocket *sioc,
if (tlscreds) {
object_ref(OBJECT(client->tlscreds));
}
- client->tlsaclname = g_strdup(tlsaclname);
+ client->tlsauthz = g_strdup(tlsauthz);
client->sioc = sioc;
object_ref(OBJECT(client->sioc));
client->ioc = QIO_CHANNEL(sioc);
diff --git a/qemu-nbd.c b/qemu-nbd.c
index 00c07fd27ea..941ba729c2f 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -58,6 +58,7 @@
#define QEMU_NBD_OPT_TLSCREDS 261
#define QEMU_NBD_OPT_IMAGE_OPTS 262
#define QEMU_NBD_OPT_FORK 263
+#define QEMU_NBD_OPT_TLSAUTHZ 264
#define MBR_SIZE 512
@@ -71,6 +72,7 @@ static int shared = 1;
static int nb_fds;
static QIONetListener *server;
static QCryptoTLSCreds *tlscreds;
+static const char *tlsauthz;
static void usage(const char *name)
{
@@ -103,6 +105,8 @@ static void usage(const char *name)
" --object type,id=ID,... define an object such as 'secret' for providing\n"
" passwords and/or encryption keys\n"
" --tls-creds=ID use id of an earlier --object to provide TLS\n"
+" --tls-authz=ID use id of an earlier --object to provide\n"
+" authorization\n"
" -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
" specify tracing options\n"
" --fork fork off the server process and exit the parent\n"
@@ -452,7 +456,7 @@ static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
nb_fds++;
nbd_update_server_watch();
- nbd_client_new(cioc, tlscreds, NULL, nbd_client_closed);
+ nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
}
static void nbd_update_server_watch(void)
@@ -643,6 +647,7 @@ int main(int argc, char **argv)
{ "export-name", required_argument, NULL, 'x' },
{ "description", required_argument, NULL, 'D' },
{ "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
+ { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
{ "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
{ "trace", required_argument, NULL, 'T' },
{ "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
@@ -862,6 +867,9 @@ int main(int argc, char **argv)
g_free(trace_file);
trace_file = trace_opt_parse(optarg);
break;
+ case QEMU_NBD_OPT_TLSAUTHZ:
+ tlsauthz = optarg;
+ break;
case QEMU_NBD_OPT_FORK:
fork_process = true;
break;
@@ -934,12 +942,21 @@ int main(int argc, char **argv)
error_report("TLS is not supported with a host device");
exit(EXIT_FAILURE);
}
+ if (tlsauthz && list) {
+ error_report("TLS authorization is incompatible with export list");
+ exit(EXIT_FAILURE);
+ }
tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
if (local_err) {
error_report("Failed to get TLS creds %s",
error_get_pretty(local_err));
exit(EXIT_FAILURE);
}
+ } else {
+ if (tlsauthz) {
+ error_report("--tls-authz is not permitted without --tls-creds");
+ exit(EXIT_FAILURE);
+ }
}
if (list) {
diff --git a/tests/qemu-iotests/233 b/tests/qemu-iotests/233
index adb742fafb0..5e5fe1e8cdb 100755
--- a/tests/qemu-iotests/233
+++ b/tests/qemu-iotests/233
@@ -61,6 +61,7 @@ tls_x509_create_root_ca "ca2"
tls_x509_create_server "ca1" "server1"
tls_x509_create_client "ca1" "client1"
tls_x509_create_client "ca2" "client2"
+tls_x509_create_client "ca1" "client3"
echo
echo "== preparing image =="
@@ -93,11 +94,15 @@ $QEMU_NBD_PROG -L -b $nbd_tcp_addr -p $nbd_tcp_port
echo
echo "== check TLS works =="
-obj=tls-creds-x509,dir=${tls_dir}/client1,endpoint=client,id=tls0
-$QEMU_IMG info --image-opts --object $obj \
+obj1=tls-creds-x509,dir=${tls_dir}/client1,endpoint=client,id=tls0
+obj2=tls-creds-x509,dir=${tls_dir}/client3,endpoint=client,id=tls0
+$QEMU_IMG info --image-opts --object $obj1 \
driver=nbd,host=$nbd_tcp_addr,port=$nbd_tcp_port,tls-creds=tls0 \
2>&1 | sed "s/$nbd_tcp_port/PORT/g"
-$QEMU_NBD_PROG -L -b $nbd_tcp_addr -p $nbd_tcp_port --object $obj \
+$QEMU_IMG info --image-opts --object $obj2 \
+ driver=nbd,host=$nbd_tcp_addr,port=$nbd_tcp_port,tls-creds=tls0 \
+ 2>&1 | sed "s/$nbd_tcp_port/PORT/g"
+$QEMU_NBD_PROG -L -b $nbd_tcp_addr -p $nbd_tcp_port --object $obj1 \
--tls-creds=tls0
echo
@@ -119,6 +124,27 @@ $QEMU_IO -c 'r -P 0x11 1m 1m' -c 'w -P 0x22 1m 1m' --image-opts \
$QEMU_IO -f $IMGFMT -r -U -c 'r -P 0x22 1m 1m' "$TEST_IMG" | _filter_qemu_io
+echo
+echo "== check TLS with authorization =="
+
+nbd_server_stop
+
+nbd_server_start_tcp_socket \
+ --object tls-creds-x509,dir=${tls_dir}/server1,endpoint=server,id=tls0,verify-peer=yes \
+ --object "authz-simple,id=authz0,identity=CN=localhost,, \
+ O=Cthulu Dark Lord Enterprises client1,,L=R'lyeh,,C=South Pacific" \
+ --tls-authz authz0 \
+ --tls-creds tls0 \
+ -f $IMGFMT "$TEST_IMG" 2>> "$TEST_DIR/server.log"
+
+$QEMU_IMG info --image-opts \
+ --object tls-creds-x509,dir=${tls_dir}/client1,endpoint=client,id=tls0 \
+ driver=nbd,host=$nbd_tcp_addr,port=$nbd_tcp_port,tls-creds=tls0
+
+$QEMU_IMG info --image-opts \
+ --object tls-creds-x509,dir=${tls_dir}/client3,endpoint=client,id=tls0 \
+ driver=nbd,host=$nbd_tcp_addr,port=$nbd_tcp_port,tls-creds=tls0
+
echo
echo "== final server log =="
cat "$TEST_DIR/server.log"
diff --git a/tests/qemu-iotests/233.out b/tests/qemu-iotests/233.out
index 6d45f3b2304..5acbc13b54a 100644
--- a/tests/qemu-iotests/233.out
+++ b/tests/qemu-iotests/233.out
@@ -6,6 +6,7 @@ Generating a self signed certificate...
Generating a signed certificate...
Generating a signed certificate...
Generating a signed certificate...
+Generating a signed certificate...
== preparing image ==
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
@@ -29,6 +30,10 @@ image: nbd://127.0.0.1:PORT
file format: nbd
virtual size: 64M (67108864 bytes)
disk size: unavailable
+image: nbd://127.0.0.1:PORT
+file format: nbd
+virtual size: 64M (67108864 bytes)
+disk size: unavailable
exports available: 1
export: ''
size: 67108864
@@ -51,7 +56,13 @@ wrote 1048576/1048576 bytes at offset 1048576
read 1048576/1048576 bytes at offset 1048576
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+== check TLS with authorization ==
+qemu-img: Could not open 'driver=nbd,host=127.0.0.1,port=10809,tls-creds=tls0': Failed to read option reply: Cannot read from TLS channel: Software caused connection abort
+qemu-img: Could not open 'driver=nbd,host=127.0.0.1,port=10809,tls-creds=tls0': Failed to read option reply: Cannot read from TLS channel: Software caused connection abort
+
== final server log ==
qemu-nbd: option negotiation failed: Verify failed: No certificate was found.
qemu-nbd: option negotiation failed: Verify failed: No certificate was found.
+qemu-nbd: option negotiation failed: TLS x509 authz check for CN=localhost,O=Cthulhu Dark Lord Enterprises client1,L=R'lyeh,C=South Pacific is denied
+qemu-nbd: option negotiation failed: TLS x509 authz check for CN=localhost,O=Cthulhu Dark Lord Enterprises client3,L=R'lyeh,C=South Pacific is denied
*** done
--
2.20.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [Qemu-devel] [PULL 2/4] nbd: allow authorization with nbd-server-start QMP command
2019-03-08 17:39 [Qemu-devel] [PULL 0/4] NBD patches for 2019-03-08, 4.0 softfreeze Eric Blake
2019-03-08 17:39 ` [Qemu-devel] [PULL 1/4] qemu-nbd: add support for authorization of TLS clients Eric Blake
@ 2019-03-08 17:39 ` Eric Blake
2019-03-08 17:39 ` [Qemu-devel] [PULL 3/4] nbd: fix outdated qapi docs syntax for tls-creds Eric Blake
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Eric Blake @ 2019-03-08 17:39 UTC (permalink / raw)
To: qemu-devel
Cc: Daniel P. Berrange, Juan Quintela, Kevin Wolf, Max Reitz,
Dr. David Alan Gilbert, Markus Armbruster,
open list:Network Block Dev...
From: "Daniel P. Berrange" <berrange@redhat.com>
As with the previous patch to qemu-nbd, the nbd-server-start QMP command
also needs to be able to specify authorization when enabling TLS encryption.
First the client must create a QAuthZ object instance using the
'object-add' command:
{
'execute': 'object-add',
'arguments': {
'qom-type': 'authz-list',
'id': 'authz0',
'parameters': {
'policy': 'deny',
'rules': [
{
'match': '*CN=fred',
'policy': 'allow'
}
]
}
}
}
They can then reference this in the new 'tls-authz' parameter when
executing the 'nbd-server-start' command:
{
'execute': 'nbd-server-start',
'arguments': {
'addr': {
'type': 'inet',
'host': '127.0.0.1',
'port': '9000'
},
'tls-creds': 'tls0',
'tls-authz': 'authz0'
}
}
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20190227162035.18543-3-berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
qapi/block.json | 8 +++++++-
include/block/nbd.h | 2 +-
blockdev-nbd.c | 11 ++++++++---
hmp.c | 2 +-
4 files changed, 17 insertions(+), 6 deletions(-)
diff --git a/qapi/block.json b/qapi/block.json
index 5a79d639e8c..79623088e72 100644
--- a/qapi/block.json
+++ b/qapi/block.json
@@ -225,6 +225,11 @@
#
# @addr: Address on which to listen.
# @tls-creds: (optional) ID of the TLS credentials object. Since 2.6
+# @tls-authz: ID of the QAuthZ authorization object used to validate
+# the client's x509 distinguished name. This object is
+# is only resolved at time of use, so can be deleted and
+# recreated on the fly while the NBD server is active.
+# If missing, it will default to denying access (since 4.0).
#
# Returns: error if the server is already running.
#
@@ -232,7 +237,8 @@
##
{ 'command': 'nbd-server-start',
'data': { 'addr': 'SocketAddressLegacy',
- '*tls-creds': 'str'} }
+ '*tls-creds': 'str',
+ '*tls-authz': 'str'} }
##
# @nbd-server-add:
diff --git a/include/block/nbd.h b/include/block/nbd.h
index b742ec4a89b..6d05983a55f 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -332,7 +332,7 @@ void nbd_client_get(NBDClient *client);
void nbd_client_put(NBDClient *client);
void nbd_server_start(SocketAddress *addr, const char *tls_creds,
- Error **errp);
+ const char *tls_authz, Error **errp);
/* nbd_read
* Reads @size bytes from @ioc. Returns 0 on success.
diff --git a/blockdev-nbd.c b/blockdev-nbd.c
index d73ac1b026a..66eebab3187 100644
--- a/blockdev-nbd.c
+++ b/blockdev-nbd.c
@@ -23,6 +23,7 @@
typedef struct NBDServerData {
QIONetListener *listener;
QCryptoTLSCreds *tlscreds;
+ char *tlsauthz;
} NBDServerData;
static NBDServerData *nbd_server;
@@ -36,7 +37,7 @@ static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
gpointer opaque)
{
qio_channel_set_name(QIO_CHANNEL(cioc), "nbd-server");
- nbd_client_new(cioc, nbd_server->tlscreds, NULL,
+ nbd_client_new(cioc, nbd_server->tlscreds, nbd_server->tlsauthz,
nbd_blockdev_client_closed);
}
@@ -52,6 +53,7 @@ static void nbd_server_free(NBDServerData *server)
if (server->tlscreds) {
object_unref(OBJECT(server->tlscreds));
}
+ g_free(server->tlsauthz);
g_free(server);
}
@@ -87,7 +89,7 @@ static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
void nbd_server_start(SocketAddress *addr, const char *tls_creds,
- Error **errp)
+ const char *tls_authz, Error **errp)
{
if (nbd_server) {
error_setg(errp, "NBD server already running");
@@ -117,6 +119,8 @@ void nbd_server_start(SocketAddress *addr, const char *tls_creds,
}
}
+ nbd_server->tlsauthz = g_strdup(tls_authz);
+
qio_net_listener_set_client_func(nbd_server->listener,
nbd_accept,
NULL,
@@ -131,11 +135,12 @@ void nbd_server_start(SocketAddress *addr, const char *tls_creds,
void qmp_nbd_server_start(SocketAddressLegacy *addr,
bool has_tls_creds, const char *tls_creds,
+ bool has_tls_authz, const char *tls_authz,
Error **errp)
{
SocketAddress *addr_flat = socket_address_flatten(addr);
- nbd_server_start(addr_flat, tls_creds, errp);
+ nbd_server_start(addr_flat, tls_creds, tls_authz, errp);
qapi_free_SocketAddress(addr_flat);
}
diff --git a/hmp.c b/hmp.c
index c2ad3f8251e..4a702d5b977 100644
--- a/hmp.c
+++ b/hmp.c
@@ -2373,7 +2373,7 @@ void hmp_nbd_server_start(Monitor *mon, const QDict *qdict)
goto exit;
}
- nbd_server_start(addr, NULL, &local_err);
+ nbd_server_start(addr, NULL, NULL, &local_err);
qapi_free_SocketAddress(addr);
if (local_err != NULL) {
goto exit;
--
2.20.1
^ permalink raw reply related [flat|nested] 6+ messages in thread