qemu-nbd: add support for --object command line arg

Allow creation of user creatable object types with qemu-nbd
via a new --object command line arg. This will be used to supply
passwords and/or encryption keys to the various block driver
backends via the recently added 'secret' object type.

 # printf letmein > mypasswd.txt
 # qemu-nbd --object secret,id=sec0,file=mypasswd.txt \
      ...other nbd args...

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-3-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Daniel P. Berrange 2016-02-10 18:41:00 +00:00 committed by Paolo Bonzini
parent 90998d5896
commit 0ab3b3375b
2 changed files with 40 additions and 0 deletions

View File

@ -24,9 +24,11 @@
#include "qemu/main-loop.h"
#include "qemu/sockets.h"
#include "qemu/error-report.h"
#include "qemu/config-file.h"
#include "block/snapshot.h"
#include "qapi/util.h"
#include "qapi/qmp/qstring.h"
#include "qom/object_interfaces.h"
#include <getopt.h>
#include <sys/socket.h>
@ -41,6 +43,7 @@
#define QEMU_NBD_OPT_AIO 2
#define QEMU_NBD_OPT_DISCARD 3
#define QEMU_NBD_OPT_DETECT_ZEROES 4
#define QEMU_NBD_OPT_OBJECT 5
static NBDExport *exp;
static int verbose;
@ -74,6 +77,9 @@ static void usage(const char *name)
" -o, --offset=OFFSET offset into the image\n"
" -P, --partition=NUM only expose partition NUM\n"
"\n"
"General purpose options:\n"
" --object type,id=ID,... define an object such as 'secret' for providing\n"
" passwords and/or encryption keys\n"
#ifdef __linux__
"Kernel NBD client support:\n"
" -c, --connect=DEV connect FILE to the local NBD device DEV\n"
@ -371,6 +377,16 @@ static SocketAddress *nbd_build_socket_address(const char *sockpath,
}
static QemuOptsList qemu_object_opts = {
.name = "object",
.implied_opt_name = "qom-type",
.head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
.desc = {
{ }
},
};
int main(int argc, char **argv)
{
BlockBackend *blk;
@ -408,6 +424,7 @@ int main(int argc, char **argv)
{ "format", 1, NULL, 'f' },
{ "persistent", 0, NULL, 't' },
{ "verbose", 0, NULL, 'v' },
{ "object", 1, NULL, QEMU_NBD_OPT_OBJECT },
{ NULL, 0, NULL, 0 }
};
int ch;
@ -433,6 +450,8 @@ int main(int argc, char **argv)
memset(&sa_sigterm, 0, sizeof(sa_sigterm));
sa_sigterm.sa_handler = termsig_handler;
sigaction(SIGTERM, &sa_sigterm, NULL);
module_call_init(MODULE_INIT_QOM);
qemu_add_opts(&qemu_object_opts);
qemu_init_exec_dir(argv[0]);
while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
@ -588,6 +607,14 @@ int main(int argc, char **argv)
case '?':
error_report("Try `%s --help' for more information.", argv[0]);
exit(EXIT_FAILURE);
case QEMU_NBD_OPT_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
optarg, true);
if (!opts) {
exit(EXIT_FAILURE);
}
} break;
}
}
@ -597,6 +624,13 @@ int main(int argc, char **argv)
exit(EXIT_FAILURE);
}
if (qemu_opts_foreach(&qemu_object_opts,
user_creatable_add_opts_foreach,
NULL, &local_err)) {
error_report_err(local_err);
exit(EXIT_FAILURE);
}
if (disconnect) {
fd = open(argv[optind], O_RDWR);
if (fd < 0) {

View File

@ -18,6 +18,12 @@ Export a QEMU disk image using the NBD protocol.
@var{dev} is an NBD device.
@table @option
@item --object type,id=@var{id},...props...
Define a new instance of the @var{type} object class identified by @var{id}.
See the @code{qemu(1)} manual page for full details of the properties
supported. The common object type that it makes sense to define is the
@code{secret} object, which is used to supply passwords and/or encryption
keys.
@item -p, --port=@var{port}
The TCP port to listen on (default @samp{10809})
@item -o, --offset=@var{offset}