mirrors/qemu
0
0
Fork 0
mirror of https://github.com/qemu/qemu.git synced 2024-12-11 12:43:55 +08:00
Code Issues Packages Projects Releases Wiki Activity
8b94ec53f3
qemu/qemu-nbd.c
Denis V. Lunev e5b815b0de qemu-nbd: regression with arguments passing into nbd_client_thread() 
Unfortunately
    commit 03b6762144
    Author: Denis V. Lunev <den@openvz.org>
    Date:   Mon Jul 17 16:55:40 2023 +0200
    qemu-nbd: pass structure into nbd_client_thread instead of plain char*
has introduced a regression. struct NbdClientOpts resides on stack inside
'if' block. This specifically means that this stack space could be reused
once the execution will leave that block of the code.

This means that parameters passed into nbd_client_thread could be
overwritten at any moment.

The patch moves the data to the namespace of main() function effectively
preserving it for the whole process lifetime.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
CC: <qemu-stable@nongnu.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230727105828.324314-1-den@openvz.org>
Signed-off-by: Eric Blake <eblake@redhat.com>
2023-07-27 08:33:44 -05:00

1214 lines
39 KiB
C
Raw Blame History

/*
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; under version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include <getopt.h>
#include <libgen.h>
#include <pthread.h>
#include "qemu/help-texts.h"
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "sysemu/block-backend.h"
#include "sysemu/runstate.h" /* for qemu_system_killed() prototype */
#include "block/block_int.h"
#include "block/nbd.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"
#include "qemu/option.h"
#include "qemu/error-report.h"
#include "qemu/config-file.h"
#include "qemu/bswap.h"
#include "qemu/log.h"
#include "qemu/systemd.h"
#include "block/snapshot.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qstring.h"
#include "qom/object_interfaces.h"
#include "io/channel-socket.h"
#include "io/net-listener.h"
#include "crypto/init.h"
#include "crypto/tlscreds.h"
#include "trace/control.h"
#include "qemu-version.h"
#ifdef CONFIG_SELINUX
#include <selinux/selinux.h>
#endif
#ifdef __linux__
#define HAVE_NBD_DEVICE 1
#else
#define HAVE_NBD_DEVICE 0
#endif
#define SOCKET_PATH "/var/lock/qemu-nbd-%s"
#define QEMU_NBD_OPT_CACHE 256
#define QEMU_NBD_OPT_AIO 257
#define QEMU_NBD_OPT_DISCARD 258
#define QEMU_NBD_OPT_DETECT_ZEROES 259
#define QEMU_NBD_OPT_OBJECT 260
#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 QEMU_NBD_OPT_PID_FILE 265
#define QEMU_NBD_OPT_SELINUX_LABEL 266
#define QEMU_NBD_OPT_TLSHOSTNAME 267
#define MBR_SIZE 512
static char *srcpath;
static SocketAddress *saddr;
static int persistent = 0;
static enum { RUNNING, TERMINATE, TERMINATED } state;
static int shared = 1;
static int nb_fds;
static QIONetListener *server;
static QCryptoTLSCreds *tlscreds;
static const char *tlsauthz;
static void usage(const char *name)
{
(printf) (
"Usage: %s [OPTIONS] FILE\n"
" or: %s -L [OPTIONS]\n"
"QEMU Disk Network Block Device Utility\n"
"\n"
" -h, --help display this help and exit\n"
" -V, --version output version information and exit\n"
"\n"
"Connection properties:\n"
" -p, --port=PORT port to listen on (default `%d')\n"
" -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
" -k, --socket=PATH path to the unix socket\n"
" (default '"SOCKET_PATH"')\n"
" -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
" -t, --persistent don't exit on the last connection\n"
" -v, --verbose display extra debugging information\n"
" -x, --export-name=NAME expose export by name (default is empty string)\n"
" -D, --description=TEXT export a human-readable description\n"
"\n"
"Exposing part of the image:\n"
" -o, --offset=OFFSET offset into the image\n"
" -A, --allocation-depth expose the allocation depth\n"
" -B, --bitmap=NAME expose a persistent dirty bitmap\n"
"\n"
"General purpose options:\n"
" -L, --list list exports available from another NBD server\n"
" --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"
" once the server is running\n"
" --pid-file=PATH store the server's process ID in the given file\n"
#ifdef CONFIG_SELINUX
" --selinux-label=LABEL set SELinux process label on listening socket\n"
#endif
#if HAVE_NBD_DEVICE
"\n"
"Kernel NBD client support:\n"
" -c, --connect=DEV connect FILE to the local NBD device DEV\n"
" -d, --disconnect disconnect the specified device\n"
#endif
"\n"
"Block device options:\n"
" -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
" -r, --read-only export read-only\n"
" -s, --snapshot use FILE as an external snapshot, create a temporary\n"
" file with backing_file=FILE, redirect the write to\n"
" the temporary one\n"
" -l, --load-snapshot=SNAPSHOT_PARAM\n"
" load an internal snapshot inside FILE and export it\n"
" as an read-only device, SNAPSHOT_PARAM format is\n"
" 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
" '[ID_OR_NAME]'\n"
" -n, --nocache disable host cache\n"
" --cache=MODE set cache mode used to access the disk image, the\n"
" valid options are: 'none', 'writeback' (default),\n"
" 'writethrough', 'directsync' and 'unsafe'\n"
" --aio=MODE set AIO mode (native, io_uring or threads)\n"
" --discard=MODE set discard mode (ignore, unmap)\n"
" --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
" --image-opts treat FILE as a full set of image options\n"
"\n"
QEMU_HELP_BOTTOM "\n"
, name, name, NBD_DEFAULT_PORT, "DEVICE");
}
static void version(const char *name)
{
printf(
"%s " QEMU_FULL_VERSION "\n"
"Written by Anthony Liguori.\n"
"\n"
QEMU_COPYRIGHT "\n"
"This is free software; see the source for copying conditions. There is NO\n"
"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
, name);
}
#ifdef CONFIG_POSIX
/*
* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
*/
void qemu_system_killed(int signum, pid_t pid)
{
qatomic_cmpxchg(&state, RUNNING, TERMINATE);
qemu_notify_event();
}
#endif /* CONFIG_POSIX */
static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
const char *hostname)
{
int ret = EXIT_FAILURE;
int rc;
Error *err = NULL;
QIOChannelSocket *sioc;
NBDExportInfo *list;
int i, j;
sioc = qio_channel_socket_new();
if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
error_report_err(err);
goto out;
}
rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
&err);
if (rc < 0) {
if (err) {
error_report_err(err);
}
goto out;
}
printf("exports available: %d\n", rc);
for (i = 0; i < rc; i++) {
printf(" export: '%s'\n", list[i].name);
if (list[i].description && *list[i].description) {
printf(" description: %s\n", list[i].description);
}
if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
static const char *const flag_names[] = {
[NBD_FLAG_READ_ONLY_BIT] = "readonly",
[NBD_FLAG_SEND_FLUSH_BIT] = "flush",
[NBD_FLAG_SEND_FUA_BIT] = "fua",
[NBD_FLAG_ROTATIONAL_BIT] = "rotational",
[NBD_FLAG_SEND_TRIM_BIT] = "trim",
[NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
[NBD_FLAG_SEND_DF_BIT] = "df",
[NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
[NBD_FLAG_SEND_RESIZE_BIT] = "resize",
[NBD_FLAG_SEND_CACHE_BIT] = "cache",
[NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
};
printf(" size: %" PRIu64 "\n", list[i].size);
printf(" flags: 0x%x (", list[i].flags);
for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
if (flag_names[bit] && (list[i].flags & (1 << bit))) {
printf(" %s", flag_names[bit]);
}
}
printf(" )\n");
}
if (list[i].min_block) {
printf(" min block: %u\n", list[i].min_block);
printf(" opt block: %u\n", list[i].opt_block);
printf(" max block: %u\n", list[i].max_block);
}
if (list[i].n_contexts) {
printf(" available meta contexts: %d\n", list[i].n_contexts);
for (j = 0; j < list[i].n_contexts; j++) {
printf(" %s\n", list[i].contexts[j]);
}
}
}
nbd_free_export_list(list, rc);
ret = EXIT_SUCCESS;
out:
object_unref(OBJECT(sioc));
return ret;
}
#if HAVE_NBD_DEVICE
static void *show_parts(void *arg)
{
char *device = arg;
int nbd;
/* linux just needs an open() to trigger
* the partition table update
* but remember to load the module with max_part != 0 :
* modprobe nbd max_part=63
*/
nbd = open(device, O_RDWR);
if (nbd >= 0) {
close(nbd);
}
return NULL;
}
struct NbdClientOpts {
char *device;
bool fork_process;
bool verbose;
};
static void *nbd_client_thread(void *arg)
{
struct NbdClientOpts *opts = arg;
NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
QIOChannelSocket *sioc;
int fd = -1;
int ret = EXIT_FAILURE;
pthread_t show_parts_thread;
Error *local_error = NULL;
sioc = qio_channel_socket_new();
if (qio_channel_socket_connect_sync(sioc,
saddr,
&local_error) < 0) {
error_report_err(local_error);
goto out;
}
if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
NULL, NULL, NULL, &info, &local_error) < 0) {
if (local_error) {
error_report_err(local_error);
}
goto out;
}
fd = open(opts->device, O_RDWR);
if (fd < 0) {
/* Linux-only, we can use %m in printf. */
error_report("Failed to open %s: %m", opts->device);
goto out;
}
if (nbd_init(fd, sioc, &info, &local_error) < 0) {
error_report_err(local_error);
goto out;
}
/* update partition table */
pthread_create(&show_parts_thread, NULL, show_parts, opts->device);
if (opts->verbose && !opts->fork_process) {
fprintf(stderr, "NBD device %s is now connected to %s\n",
opts->device, srcpath);
} else {
/* Close stderr so that the qemu-nbd process exits. */
if (dup2(STDOUT_FILENO, STDERR_FILENO) < 0) {
error_report("Could not set stderr to /dev/null: %s",
strerror(errno));
exit(EXIT_FAILURE);
}
}
if (nbd_client(fd) < 0) {
goto out;
}
ret = EXIT_SUCCESS;
out:
if (fd >= 0) {
close(fd);
}
object_unref(OBJECT(sioc));
g_free(info.name);
kill(getpid(), SIGTERM);
return (void *) (intptr_t) ret;
}
#endif /* HAVE_NBD_DEVICE */
static int nbd_can_accept(void)
{
return state == RUNNING && (shared == 0 || nb_fds < shared);
}
static void nbd_update_server_watch(void);
static void nbd_client_closed(NBDClient *client, bool negotiated)
{
nb_fds--;
if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
state = TERMINATE;
}
nbd_update_server_watch();
nbd_client_put(client);
}
static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
gpointer opaque)
{
if (state >= TERMINATE) {
return;
}
nb_fds++;
nbd_update_server_watch();
nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
}
static void nbd_update_server_watch(void)
{
if (nbd_can_accept()) {
qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
} else {
qio_net_listener_set_client_func(server, NULL, NULL, NULL);
}
}
static SocketAddress *nbd_build_socket_address(const char *sockpath,
const char *bindto,
const char *port)
{
SocketAddress *saddr;
saddr = g_new0(SocketAddress, 1);
if (sockpath) {
saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
saddr->u.q_unix.path = g_strdup(sockpath);
} else {
InetSocketAddress *inet;
saddr->type = SOCKET_ADDRESS_TYPE_INET;
inet = &saddr->u.inet;
inet->host = g_strdup(bindto);
if (port) {
inet->port = g_strdup(port);
} else {
inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
}
}
return saddr;
}
static QemuOptsList file_opts = {
.name = "file",
.implied_opt_name = "file",
.head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
.desc = {
/* no elements => accept any params */
{ /* end of list */ }
},
};
static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
Error **errp)
{
Object *obj;
QCryptoTLSCreds *creds;
obj = object_resolve_path_component(
object_get_objects_root(), id);
if (!obj) {
error_setg(errp, "No TLS credentials with id '%s'",
id);
return NULL;
}
creds = (QCryptoTLSCreds *)
object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
if (!creds) {
error_setg(errp, "Object with id '%s' is not TLS credentials",
id);
return NULL;
}
if (!qcrypto_tls_creds_check_endpoint(creds,
list
? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT
: QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
errp)) {
return NULL;
}
object_ref(obj);
return creds;
}
static void setup_address_and_port(const char **address, const char **port)
{
if (*address == NULL) {
*address = "0.0.0.0";
}
if (*port == NULL) {
*port = stringify(NBD_DEFAULT_PORT);
}
}
/*
* Check socket parameters compatibility when socket activation is used.
*/
static const char *socket_activation_validate_opts(const char *device,
const char *sockpath,
const char *address,
const char *port,
const char *selinux,
bool list)
{
if (device != NULL) {
return "NBD device can't be set when using socket activation";
}
if (sockpath != NULL) {
return "Unix socket can't be set when using socket activation";
}
if (address != NULL) {
return "The interface can't be set when using socket activation";
}
if (port != NULL) {
return "TCP port number can't be set when using socket activation";
}
if (selinux != NULL) {
return "SELinux label can't be set when using socket activation";
}
if (list) {
return "List mode is incompatible with socket activation";
}
return NULL;
}
static void qemu_nbd_shutdown(void)
{
job_cancel_sync_all();
blk_exp_close_all();
bdrv_close_all();
}
int main(int argc, char **argv)
{
BlockBackend *blk;
BlockDriverState *bs;
uint64_t dev_offset = 0;
bool readonly = false;
bool disconnect = false;
const char *bindto = NULL;
const char *port = NULL;
char *sockpath = NULL;
char *device = NULL;
QemuOpts *sn_opts = NULL;
const char *sn_id_or_name = NULL;
const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
struct option lopt[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
{ "bind", required_argument, NULL, 'b' },
{ "port", required_argument, NULL, 'p' },
{ "socket", required_argument, NULL, 'k' },
{ "offset", required_argument, NULL, 'o' },
{ "read-only", no_argument, NULL, 'r' },
{ "allocation-depth", no_argument, NULL, 'A' },
{ "bitmap", required_argument, NULL, 'B' },
{ "connect", required_argument, NULL, 'c' },
{ "disconnect", no_argument, NULL, 'd' },
{ "list", no_argument, NULL, 'L' },
{ "snapshot", no_argument, NULL, 's' },
{ "load-snapshot", required_argument, NULL, 'l' },
{ "nocache", no_argument, NULL, 'n' },
{ "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
{ "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
{ "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
{ "detect-zeroes", required_argument, NULL,
QEMU_NBD_OPT_DETECT_ZEROES },
{ "shared", required_argument, NULL, 'e' },
{ "format", required_argument, NULL, 'f' },
{ "persistent", no_argument, NULL, 't' },
{ "verbose", no_argument, NULL, 'v' },
{ "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
{ "export-name", required_argument, NULL, 'x' },
{ "description", required_argument, NULL, 'D' },
{ "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
{ "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME },
{ "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 },
{ "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
{ "selinux-label", required_argument, NULL,
QEMU_NBD_OPT_SELINUX_LABEL },
{ NULL, 0, NULL, 0 }
};
int ch;
int opt_ind = 0;
int flags = BDRV_O_RDWR;
int ret = 0;
bool seen_cache = false;
bool seen_discard = false;
bool seen_aio = false;
pthread_t client_thread;
const char *fmt = NULL;
Error *local_err = NULL;
BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
QDict *options = NULL;
const char *export_name = NULL; /* defaults to "" later for server mode */
const char *export_description = NULL;
BlockDirtyBitmapOrStrList *bitmaps = NULL;
bool alloc_depth = false;
const char *tlscredsid = NULL;
const char *tlshostname = NULL;
bool imageOpts = false;
bool writethrough = false; /* Client will flush as needed. */
bool verbose = false;
bool fork_process = false;
bool list = false;
unsigned socket_activation;
const char *pid_file_name = NULL;
const char *selinux_label = NULL;
BlockExportOptions *export_opts;
#if HAVE_NBD_DEVICE
struct NbdClientOpts opts;
#endif
#ifdef CONFIG_POSIX
os_setup_early_signal_handling();
os_setup_signal_handling();
#endif
socket_init();
error_init(argv[0]);
module_call_init(MODULE_INIT_TRACE);
qcrypto_init(&error_fatal);
module_call_init(MODULE_INIT_QOM);
qemu_add_opts(&qemu_trace_opts);
qemu_init_exec_dir(argv[0]);
while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
switch (ch) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
optarg = (char *) "none";
/* fallthrough */
case QEMU_NBD_OPT_CACHE:
if (seen_cache) {
error_report("-n and --cache can only be specified once");
exit(EXIT_FAILURE);
}
seen_cache = true;
if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
error_report("Invalid cache mode `%s'", optarg);
exit(EXIT_FAILURE);
}
break;
case QEMU_NBD_OPT_AIO:
if (seen_aio) {
error_report("--aio can only be specified once");
exit(EXIT_FAILURE);
}
seen_aio = true;
if (bdrv_parse_aio(optarg, &flags) < 0) {
error_report("Invalid aio mode '%s'", optarg);
exit(EXIT_FAILURE);
}
break;
case QEMU_NBD_OPT_DISCARD:
if (seen_discard) {
error_report("--discard can only be specified once");
exit(EXIT_FAILURE);
}
seen_discard = true;
if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
error_report("Invalid discard mode `%s'", optarg);
exit(EXIT_FAILURE);
}
break;
case QEMU_NBD_OPT_DETECT_ZEROES:
detect_zeroes =
qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
optarg,
BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
&local_err);
if (local_err) {
error_reportf_err(local_err,
"Failed to parse detect_zeroes mode: ");
exit(EXIT_FAILURE);
}
if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
!(flags & BDRV_O_UNMAP)) {
error_report("setting detect-zeroes to unmap is not allowed "
"without setting discard operation to unmap");
exit(EXIT_FAILURE);
}
break;
case 'b':
bindto = optarg;
break;
case 'p':
port = optarg;
break;
case 'o':
if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
error_report("Invalid offset '%s'", optarg);
exit(EXIT_FAILURE);
}
break;
case 'l':
if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
optarg, false);
if (!sn_opts) {
error_report("Failed in parsing snapshot param `%s'",
optarg);
exit(EXIT_FAILURE);
}
} else {
sn_id_or_name = optarg;
}
/* fall through */
case 'r':
readonly = true;
flags &= ~BDRV_O_RDWR;
break;
case 'A':
alloc_depth = true;
break;
case 'B':
{
BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1);
*el = (BlockDirtyBitmapOrStr) {
.type = QTYPE_QSTRING,
.u.local = g_strdup(optarg),
};
QAPI_LIST_PREPEND(bitmaps, el);
}
break;
case 'k':
sockpath = optarg;
if (sockpath[0] != '/') {
error_report("socket path must be absolute");
exit(EXIT_FAILURE);
}
break;
case 'd':
disconnect = true;
break;
case 'c':
device = optarg;
break;
case 'e':
if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
shared < 0) {
error_report("Invalid shared device number '%s'", optarg);
exit(EXIT_FAILURE);
}
break;
case 'f':
fmt = optarg;
break;
case 't':
persistent = 1;
break;
case 'x':
export_name = optarg;
if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
error_report("export name '%s' too long", export_name);
exit(EXIT_FAILURE);
}
break;
case 'D':
export_description = optarg;
if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
error_report("export description '%s' too long",
export_description);
exit(EXIT_FAILURE);
}
break;
case 'v':
verbose = true;
break;
case 'V':
version(argv[0]);
exit(0);
break;
case 'h':
usage(argv[0]);
exit(0);
break;
case '?':
error_report("Try `%s --help' for more information.", argv[0]);
exit(EXIT_FAILURE);
case QEMU_NBD_OPT_OBJECT:
user_creatable_process_cmdline(optarg);
break;
case QEMU_NBD_OPT_TLSCREDS:
tlscredsid = optarg;
break;
case QEMU_NBD_OPT_TLSHOSTNAME:
tlshostname = optarg;
break;
case QEMU_NBD_OPT_IMAGE_OPTS:
imageOpts = true;
break;
case 'T':
trace_opt_parse(optarg);
break;
case QEMU_NBD_OPT_TLSAUTHZ:
tlsauthz = optarg;
break;
case QEMU_NBD_OPT_FORK:
fork_process = true;
break;
case 'L':
list = true;
break;
case QEMU_NBD_OPT_PID_FILE:
pid_file_name = optarg;
break;
case QEMU_NBD_OPT_SELINUX_LABEL:
selinux_label = optarg;
break;
}
}
if (list) {
if (argc != optind) {
error_report("List mode is incompatible with a file name");
exit(EXIT_FAILURE);
}
if (export_name || export_description || dev_offset ||
device || disconnect || fmt || sn_id_or_name || bitmaps ||
alloc_depth || seen_aio || seen_discard || seen_cache) {
error_report("List mode is incompatible with per-device settings");
exit(EXIT_FAILURE);
}
if (fork_process) {
error_report("List mode is incompatible with forking");
exit(EXIT_FAILURE);
}
} else if ((argc - optind) != 1) {
error_report("Invalid number of arguments");
error_printf("Try `%s --help' for more information.\n", argv[0]);
exit(EXIT_FAILURE);
} else if (!export_name) {
export_name = "";
}
if (!trace_init_backends()) {
exit(1);
}
trace_init_file();
qemu_set_log(LOG_TRACE, &error_fatal);
socket_activation = check_socket_activation();
if (socket_activation == 0) {
if (!sockpath) {
setup_address_and_port(&bindto, &port);
}
} else {
/* Using socket activation - check user didn't use -p etc. */
const char *err_msg = socket_activation_validate_opts(device, sockpath,
bindto, port,
selinux_label,
list);
if (err_msg != NULL) {
error_report("%s", err_msg);
exit(EXIT_FAILURE);
}
/* qemu-nbd can only listen on a single socket. */
if (socket_activation > 1) {
error_report("qemu-nbd does not support socket activation with %s > 1",
"LISTEN_FDS");
exit(EXIT_FAILURE);
}
}
if (tlscredsid) {
if (device) {
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);
}
if (tlshostname && !list) {
error_report("TLS hostname is only supported with export list");
exit(EXIT_FAILURE);
}
tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
if (local_err) {
error_reportf_err(local_err, "Failed to get TLS creds: ");
exit(EXIT_FAILURE);
}
} else {
if (tlsauthz) {
error_report("--tls-authz is not permitted without --tls-creds");
exit(EXIT_FAILURE);
}
if (tlshostname) {
error_report("--tls-hostname is not permitted without --tls-creds");
exit(EXIT_FAILURE);
}
}
if (selinux_label) {
#ifdef CONFIG_SELINUX
if (sockpath == NULL && device == NULL) {
error_report("--selinux-label is not permitted without --socket");
exit(EXIT_FAILURE);
}
#else
error_report("SELinux support not enabled in this binary");
exit(EXIT_FAILURE);
#endif
}
if (list) {
saddr = nbd_build_socket_address(sockpath, bindto, port);
return qemu_nbd_client_list(saddr, tlscreds,
tlshostname ? tlshostname : bindto);
}
#if !HAVE_NBD_DEVICE
if (disconnect || device) {
error_report("Kernel /dev/nbdN support not available");
exit(EXIT_FAILURE);
}
#else /* HAVE_NBD_DEVICE */
if (disconnect) {
int nbdfd = open(argv[optind], O_RDWR);
if (nbdfd < 0) {
error_report("Cannot open %s: %s", argv[optind],
strerror(errno));
exit(EXIT_FAILURE);
}
nbd_disconnect(nbdfd);
close(nbdfd);
printf("%s disconnected\n", argv[optind]);
return 0;
}
#endif
if ((device && !verbose) || fork_process) {
#ifndef WIN32
g_autoptr(GError) err = NULL;
int stderr_fd[2];
pid_t pid;
int ret;
if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) {
error_report("Error setting up communication pipe: %s",
err->message);
exit(EXIT_FAILURE);
}
/* Now daemonize, but keep a communication channel open to
* print errors and exit with the proper status code.
*/
pid = fork();
if (pid < 0) {
error_report("Failed to fork: %s", strerror(errno));
exit(EXIT_FAILURE);
} else if (pid == 0) {
int saved_errno;
close(stderr_fd[0]);
ret = qemu_daemon(1, 0);
saved_errno = errno; /* dup2 will overwrite error below */
/* Temporarily redirect stderr to the parent's pipe... */
if (dup2(stderr_fd[1], STDERR_FILENO) < 0) {
char str[256];
snprintf(str, sizeof(str),
"%s: Failed to link stderr to the pipe: %s\n",
g_get_prgname(), strerror(errno));
/*
* We are unable to use error_report() here as we need to get
* stderr pointed to the parent's pipe. Write to that pipe
* manually.
*/
ret = write(stderr_fd[1], str, strlen(str));
exit(EXIT_FAILURE);
}
if (ret < 0) {
error_report("Failed to daemonize: %s", strerror(saved_errno));
exit(EXIT_FAILURE);
}
/* ... close the descriptor we inherited and go on. */
close(stderr_fd[1]);
} else {
bool errors = false;
char *buf;
/* In the parent. Print error messages from the child until
* it closes the pipe.
*/
close(stderr_fd[1]);
buf = g_malloc(1024);
while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
errors = true;
ret = qemu_write_full(STDERR_FILENO, buf, ret);
if (ret < 0) {
exit(EXIT_FAILURE);
}
}
if (ret < 0) {
error_report("Cannot read from daemon: %s",
strerror(errno));
exit(EXIT_FAILURE);
}
/* Usually the daemon should not print any message.
* Exit with zero status in that case.
*/
exit(errors);
}
#else /* WIN32 */
error_report("Unable to fork into background on Windows hosts");
exit(EXIT_FAILURE);
#endif /* WIN32 */
}
if (device != NULL && sockpath == NULL) {
sockpath = g_malloc(128);
snprintf(sockpath, 128, SOCKET_PATH, basename(device));
}
server = qio_net_listener_new();
if (socket_activation == 0) {
int backlog;
if (persistent || shared == 0) {
backlog = SOMAXCONN;
} else {
backlog = MIN(shared, SOMAXCONN);
}
#ifdef CONFIG_SELINUX
if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) {
error_report("Cannot set SELinux socket create context to %s: %s",
selinux_label, strerror(errno));
exit(EXIT_FAILURE);
}
#endif
saddr = nbd_build_socket_address(sockpath, bindto, port);
if (qio_net_listener_open_sync(server, saddr, backlog,
&local_err) < 0) {
object_unref(OBJECT(server));
error_report_err(local_err);
exit(EXIT_FAILURE);
}
#ifdef CONFIG_SELINUX
if (selinux_label && setsockcreatecon_raw(NULL) == -1) {
error_report("Cannot clear SELinux socket create context: %s",
strerror(errno));
exit(EXIT_FAILURE);
}
#endif
} else {
size_t i;
/* See comment in check_socket_activation above. */
for (i = 0; i < socket_activation; i++) {
QIOChannelSocket *sioc;
sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
&local_err);
if (sioc == NULL) {
object_unref(OBJECT(server));
error_reportf_err(local_err,
"Failed to use socket activation: ");
exit(EXIT_FAILURE);
}
qio_net_listener_add(server, sioc);
object_unref(OBJECT(sioc));
}
}
qemu_init_main_loop(&error_fatal);
bdrv_init();
atexit(qemu_nbd_shutdown);
srcpath = argv[optind];
if (imageOpts) {
QemuOpts *opts;
if (fmt) {
error_report("--image-opts and -f are mutually exclusive");
exit(EXIT_FAILURE);
}
opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
if (!opts) {
qemu_opts_reset(&file_opts);
exit(EXIT_FAILURE);
}
options = qemu_opts_to_qdict(opts, NULL);
qemu_opts_reset(&file_opts);
blk = blk_new_open(NULL, NULL, options, flags, &local_err);
} else {
if (fmt) {
options = qdict_new();
qdict_put_str(options, "driver", fmt);
}
blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
}
if (!blk) {
error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
argv[optind]);
exit(EXIT_FAILURE);
}
bs = blk_bs(blk);
if (dev_offset) {
QDict *raw_opts = qdict_new();
qdict_put_str(raw_opts, "driver", "raw");
qdict_put_str(raw_opts, "file", bs->node_name);
qdict_put_int(raw_opts, "offset", dev_offset);
aio_context_acquire(qemu_get_aio_context());
bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
aio_context_release(qemu_get_aio_context());
blk_remove_bs(blk);
blk_insert_bs(blk, bs, &error_fatal);
bdrv_unref(bs);
}
blk_set_enable_write_cache(blk, !writethrough);
if (sn_opts) {
ret = bdrv_snapshot_load_tmp(bs,
qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
&local_err);
} else if (sn_id_or_name) {
ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
&local_err);
}
if (ret < 0) {
error_reportf_err(local_err, "Failed to load snapshot: ");
exit(EXIT_FAILURE);
}
bs->detect_zeroes = detect_zeroes;
nbd_server_is_qemu_nbd(shared);
export_opts = g_new(BlockExportOptions, 1);
*export_opts = (BlockExportOptions) {
.type = BLOCK_EXPORT_TYPE_NBD,
.id = g_strdup("qemu-nbd-export"),
.node_name = g_strdup(bdrv_get_node_name(bs)),
.has_writethrough = true,
.writethrough = writethrough,
.has_writable = true,
.writable = !readonly,
.u.nbd = {
.name = g_strdup(export_name),
.description = g_strdup(export_description),
.has_bitmaps = !!bitmaps,
.bitmaps = bitmaps,
.has_allocation_depth = alloc_depth,
.allocation_depth = alloc_depth,
},
};
blk_exp_add(export_opts, &error_fatal);
qapi_free_BlockExportOptions(export_opts);
if (device) {
#if HAVE_NBD_DEVICE
int ret;
opts = (struct NbdClientOpts) {
.device = device,
.fork_process = fork_process,
.verbose = verbose,
};
ret = pthread_create(&client_thread, NULL, nbd_client_thread, &opts);
if (ret != 0) {
error_report("Failed to create client thread: %s", strerror(ret));
exit(EXIT_FAILURE);
}
#endif
} else {
/* Shut up GCC warnings. */
memset(&client_thread, 0, sizeof(client_thread));
}
nbd_update_server_watch();
if (pid_file_name) {
qemu_write_pidfile(pid_file_name, &error_fatal);
}
/* now when the initialization is (almost) complete, chdir("/")
* to free any busy filesystems */
if (chdir("/") < 0) {
error_report("Could not chdir to root directory: %s",
strerror(errno));
exit(EXIT_FAILURE);
}
if (fork_process) {
if (dup2(STDOUT_FILENO, STDERR_FILENO) < 0) {
error_report("Could not set stderr to /dev/null: %s",
strerror(errno));
exit(EXIT_FAILURE);
}
}
state = RUNNING;
do {
main_loop_wait(false);
if (state == TERMINATE) {
blk_exp_close_all();
state = TERMINATED;
}
} while (state != TERMINATED);
blk_unref(blk);
if (sockpath) {
unlink(sockpath);
}
qemu_opts_del(sn_opts);
if (device) {
void *ret;
pthread_join(client_thread, &ret);
exit(ret != NULL);
} else {
exit(EXIT_SUCCESS);
}
}
Reference in New Issue View Git Blame Copy Permalink