1 /*
2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
3 *
4 * Network Block Device
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; under version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
17 */
18
19 #include "qemu/osdep.h"
20 #include <getopt.h>
21 #include <libgen.h>
22 #include <pthread.h>
23
24 #include "qemu/help-texts.h"
25 #include "qapi/error.h"
26 #include "qemu/cutils.h"
27 #include "sysemu/block-backend.h"
28 #include "sysemu/runstate.h" /* for qemu_system_killed() prototype */
29 #include "block/block_int.h"
30 #include "block/nbd.h"
31 #include "qemu/main-loop.h"
32 #include "qemu/module.h"
33 #include "qemu/option.h"
34 #include "qemu/error-report.h"
35 #include "qemu/config-file.h"
36 #include "qemu/bswap.h"
37 #include "qemu/log.h"
38 #include "qemu/systemd.h"
39 #include "block/snapshot.h"
40 #include "qapi/qmp/qdict.h"
41 #include "qapi/qmp/qstring.h"
42 #include "qom/object_interfaces.h"
43 #include "io/channel-socket.h"
44 #include "io/net-listener.h"
45 #include "crypto/init.h"
46 #include "crypto/tlscreds.h"
47 #include "trace/control.h"
48 #include "qemu-version.h"
49
50 #ifdef CONFIG_SELINUX
51 #include <selinux/selinux.h>
52 #endif
53
54 #ifdef __linux__
55 #define HAVE_NBD_DEVICE 1
56 #else
57 #define HAVE_NBD_DEVICE 0
58 #endif
59
60 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
61 #define QEMU_NBD_OPT_CACHE 256
62 #define QEMU_NBD_OPT_AIO 257
63 #define QEMU_NBD_OPT_DISCARD 258
64 #define QEMU_NBD_OPT_DETECT_ZEROES 259
65 #define QEMU_NBD_OPT_OBJECT 260
66 #define QEMU_NBD_OPT_TLSCREDS 261
67 #define QEMU_NBD_OPT_IMAGE_OPTS 262
68 #define QEMU_NBD_OPT_FORK 263
69 #define QEMU_NBD_OPT_TLSAUTHZ 264
70 #define QEMU_NBD_OPT_PID_FILE 265
71 #define QEMU_NBD_OPT_SELINUX_LABEL 266
72 #define QEMU_NBD_OPT_TLSHOSTNAME 267
73
74 #define MBR_SIZE 512
75
76 static int persistent = 0;
77 static enum { RUNNING, TERMINATE, TERMINATED } state;
78 static int shared = 1;
79 static int nb_fds;
80 static QIONetListener *server;
81 static QCryptoTLSCreds *tlscreds;
82 static const char *tlsauthz;
83
usage(const char * name)84 static void usage(const char *name)
85 {
86 (printf) (
87 "Usage: %s [OPTIONS] FILE\n"
88 " or: %s -L [OPTIONS]\n"
89 "QEMU Disk Network Block Device Utility\n"
90 "\n"
91 " -h, --help display this help and exit\n"
92 " -V, --version output version information and exit\n"
93 "\n"
94 "Connection properties:\n"
95 " -p, --port=PORT port to listen on (default `%d')\n"
96 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
97 " -k, --socket=PATH path to the unix socket\n"
98 " (default '"SOCKET_PATH"')\n"
99 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
100 " -t, --persistent don't exit on the last connection\n"
101 " -v, --verbose display extra debugging information\n"
102 " -x, --export-name=NAME expose export by name (default is empty string)\n"
103 " -D, --description=TEXT export a human-readable description\n"
104 "\n"
105 "Exposing part of the image:\n"
106 " -o, --offset=OFFSET offset into the image\n"
107 " -A, --allocation-depth expose the allocation depth\n"
108 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
109 "\n"
110 "General purpose options:\n"
111 " -L, --list list exports available from another NBD server\n"
112 " --object type,id=ID,... define an object such as 'secret' for providing\n"
113 " passwords and/or encryption keys\n"
114 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
115 " --tls-authz=ID use id of an earlier --object to provide\n"
116 " authorization\n"
117 " --tls-hostname=HOSTNAME override hostname used to check x509 certificate\n"
118 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
119 " specify tracing options\n"
120 " --fork fork off the server process and exit the parent\n"
121 " once the server is running\n"
122 " --pid-file=PATH store the server's process ID in the given file\n"
123 #ifdef CONFIG_SELINUX
124 " --selinux-label=LABEL set SELinux process label on listening socket\n"
125 #endif
126 #if HAVE_NBD_DEVICE
127 "\n"
128 "Kernel NBD client support:\n"
129 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
130 " -d, --disconnect disconnect the specified device\n"
131 #endif
132 "\n"
133 "Block device options:\n"
134 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
135 " -r, --read-only export read-only\n"
136 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
137 " file with backing_file=FILE, redirect the write to\n"
138 " the temporary one\n"
139 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
140 " load an internal snapshot inside FILE and export it\n"
141 " as an read-only device, SNAPSHOT_PARAM format is\n"
142 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
143 " '[ID_OR_NAME]'\n"
144 " -n, --nocache disable host cache\n"
145 " --cache=MODE set cache mode used to access the disk image, the\n"
146 " valid options are: 'none', 'writeback' (default),\n"
147 " 'writethrough', 'directsync' and 'unsafe'\n"
148 " --aio=MODE set AIO mode (native, io_uring or threads)\n"
149 " --discard=MODE set discard mode (ignore, unmap)\n"
150 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
151 " --image-opts treat FILE as a full set of image options\n"
152 "\n"
153 QEMU_HELP_BOTTOM "\n"
154 , name, name, NBD_DEFAULT_PORT, "DEVICE");
155 }
156
version(const char * name)157 static void version(const char *name)
158 {
159 printf(
160 "%s " QEMU_FULL_VERSION "\n"
161 "Written by Anthony Liguori.\n"
162 "\n"
163 QEMU_COPYRIGHT "\n"
164 "This is free software; see the source for copying conditions. There is NO\n"
165 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
166 , name);
167 }
168
169 #ifdef CONFIG_POSIX
170 /*
171 * The client thread uses SIGTERM to interrupt the server. A signal
172 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
173 */
qemu_system_killed(int signum,pid_t pid)174 void qemu_system_killed(int signum, pid_t pid)
175 {
176 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
177 qemu_notify_event();
178 }
179 #endif /* CONFIG_POSIX */
180
qemu_nbd_client_list(SocketAddress * saddr,QCryptoTLSCreds * tls,const char * hostname)181 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
182 const char *hostname)
183 {
184 int ret = EXIT_FAILURE;
185 int rc;
186 Error *err = NULL;
187 QIOChannelSocket *sioc;
188 NBDExportInfo *list;
189 int i, j;
190
191 sioc = qio_channel_socket_new();
192 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
193 error_report_err(err);
194 goto out;
195 }
196 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
197 &err);
198 if (rc < 0) {
199 if (err) {
200 error_report_err(err);
201 }
202 goto out;
203 }
204 printf("exports available: %d\n", rc);
205 for (i = 0; i < rc; i++) {
206 printf(" export: '%s'\n", list[i].name);
207 if (list[i].description && *list[i].description) {
208 printf(" description: %s\n", list[i].description);
209 }
210 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
211 static const char *const flag_names[] = {
212 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
213 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
214 [NBD_FLAG_SEND_FUA_BIT] = "fua",
215 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
216 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
217 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
218 [NBD_FLAG_SEND_DF_BIT] = "df",
219 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
220 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
221 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
222 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
223 [NBD_FLAG_BLOCK_STAT_PAYLOAD_BIT] = "block-status-payload",
224 };
225
226 printf(" size: %" PRIu64 "\n", list[i].size);
227 printf(" flags: 0x%x (", list[i].flags);
228 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
229 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
230 printf(" %s", flag_names[bit]);
231 }
232 }
233 printf(" )\n");
234 }
235 if (list[i].min_block) {
236 printf(" min block: %u\n", list[i].min_block);
237 printf(" opt block: %u\n", list[i].opt_block);
238 printf(" max block: %u\n", list[i].max_block);
239 }
240 printf(" transaction size: %s\n",
241 list[i].mode >= NBD_MODE_EXTENDED ?
242 "64-bit" : "32-bit");
243 if (list[i].n_contexts) {
244 printf(" available meta contexts: %d\n", list[i].n_contexts);
245 for (j = 0; j < list[i].n_contexts; j++) {
246 printf(" %s\n", list[i].contexts[j]);
247 }
248 }
249 }
250 nbd_free_export_list(list, rc);
251
252 ret = EXIT_SUCCESS;
253 out:
254 object_unref(OBJECT(sioc));
255 return ret;
256 }
257
258
259 struct NbdClientOpts {
260 char *device;
261 char *srcpath;
262 SocketAddress *saddr;
263 int old_stderr;
264 bool fork_process;
265 bool verbose;
266 };
267
nbd_client_release_pipe(int old_stderr)268 static void nbd_client_release_pipe(int old_stderr)
269 {
270 /* Close stderr so that the qemu-nbd process exits. */
271 if (dup2(old_stderr, STDERR_FILENO) < 0) {
272 error_report("Could not release pipe to parent: %s",
273 strerror(errno));
274 exit(EXIT_FAILURE);
275 }
276 if (old_stderr != STDOUT_FILENO && close(old_stderr) < 0) {
277 error_report("Could not release qemu-nbd: %s", strerror(errno));
278 exit(EXIT_FAILURE);
279 }
280 }
281
282 #if HAVE_NBD_DEVICE
show_parts(void * arg)283 static void *show_parts(void *arg)
284 {
285 char *device = arg;
286 int nbd;
287
288 /* linux just needs an open() to trigger
289 * the partition table update
290 * but remember to load the module with max_part != 0 :
291 * modprobe nbd max_part=63
292 */
293 nbd = open(device, O_RDWR);
294 if (nbd >= 0) {
295 close(nbd);
296 }
297 return NULL;
298 }
299
nbd_client_thread(void * arg)300 static void *nbd_client_thread(void *arg)
301 {
302 struct NbdClientOpts *opts = arg;
303 /* TODO: Revisit this if nbd.ko ever gains support for structured reply */
304 NBDExportInfo info = { .request_sizes = false, .name = g_strdup(""),
305 .mode = NBD_MODE_SIMPLE };
306 QIOChannelSocket *sioc;
307 int fd = -1;
308 int ret = EXIT_FAILURE;
309 pthread_t show_parts_thread;
310 Error *local_error = NULL;
311
312 sioc = qio_channel_socket_new();
313 if (qio_channel_socket_connect_sync(sioc,
314 opts->saddr,
315 &local_error) < 0) {
316 error_report_err(local_error);
317 goto out;
318 }
319
320 if (nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, NULL, NULL,
321 &info, &local_error) < 0) {
322 if (local_error) {
323 error_report_err(local_error);
324 }
325 goto out;
326 }
327
328 fd = open(opts->device, O_RDWR);
329 if (fd < 0) {
330 /* Linux-only, we can use %m in printf. */
331 error_report("Failed to open %s: %m", opts->device);
332 goto out;
333 }
334
335 if (nbd_init(fd, sioc, &info, &local_error) < 0) {
336 error_report_err(local_error);
337 goto out;
338 }
339
340 /* update partition table */
341 pthread_create(&show_parts_thread, NULL, show_parts, opts->device);
342
343 if (opts->verbose && !opts->fork_process) {
344 fprintf(stderr, "NBD device %s is now connected to %s\n",
345 opts->device, opts->srcpath);
346 } else {
347 nbd_client_release_pipe(opts->old_stderr);
348 }
349
350 if (nbd_client(fd) < 0) {
351 goto out;
352 }
353
354 ret = EXIT_SUCCESS;
355
356 out:
357 if (fd >= 0) {
358 close(fd);
359 }
360 object_unref(OBJECT(sioc));
361 g_free(info.name);
362 kill(getpid(), SIGTERM);
363 return (void *) (intptr_t) ret;
364 }
365 #endif /* HAVE_NBD_DEVICE */
366
nbd_can_accept(void)367 static int nbd_can_accept(void)
368 {
369 return state == RUNNING && (shared == 0 || nb_fds < shared);
370 }
371
372 static void nbd_update_server_watch(void);
373
nbd_client_closed(NBDClient * client,bool negotiated)374 static void nbd_client_closed(NBDClient *client, bool negotiated)
375 {
376 nb_fds--;
377 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
378 state = TERMINATE;
379 }
380 nbd_update_server_watch();
381 nbd_client_put(client);
382 }
383
nbd_accept(QIONetListener * listener,QIOChannelSocket * cioc,gpointer opaque)384 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
385 gpointer opaque)
386 {
387 if (state >= TERMINATE) {
388 return;
389 }
390
391 nb_fds++;
392 nbd_update_server_watch();
393 /* TODO - expose handshake timeout as command line option */
394 nbd_client_new(cioc, NBD_DEFAULT_HANDSHAKE_MAX_SECS,
395 tlscreds, tlsauthz, nbd_client_closed, NULL);
396 }
397
nbd_update_server_watch(void)398 static void nbd_update_server_watch(void)
399 {
400 if (nbd_can_accept()) {
401 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
402 } else {
403 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
404 }
405 }
406
407
nbd_build_socket_address(const char * sockpath,const char * bindto,const char * port)408 static SocketAddress *nbd_build_socket_address(const char *sockpath,
409 const char *bindto,
410 const char *port)
411 {
412 SocketAddress *saddr;
413
414 saddr = g_new0(SocketAddress, 1);
415 if (sockpath) {
416 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
417 saddr->u.q_unix.path = g_strdup(sockpath);
418 } else {
419 InetSocketAddress *inet;
420 saddr->type = SOCKET_ADDRESS_TYPE_INET;
421 inet = &saddr->u.inet;
422 inet->host = g_strdup(bindto);
423 if (port) {
424 inet->port = g_strdup(port);
425 } else {
426 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
427 }
428 }
429
430 return saddr;
431 }
432
433
434 static QemuOptsList file_opts = {
435 .name = "file",
436 .implied_opt_name = "file",
437 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
438 .desc = {
439 /* no elements => accept any params */
440 { /* end of list */ }
441 },
442 };
443
nbd_get_tls_creds(const char * id,bool list,Error ** errp)444 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
445 Error **errp)
446 {
447 Object *obj;
448 QCryptoTLSCreds *creds;
449
450 obj = object_resolve_path_component(
451 object_get_objects_root(), id);
452 if (!obj) {
453 error_setg(errp, "No TLS credentials with id '%s'",
454 id);
455 return NULL;
456 }
457 creds = (QCryptoTLSCreds *)
458 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
459 if (!creds) {
460 error_setg(errp, "Object with id '%s' is not TLS credentials",
461 id);
462 return NULL;
463 }
464
465 if (!qcrypto_tls_creds_check_endpoint(creds,
466 list
467 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT
468 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
469 errp)) {
470 return NULL;
471 }
472 object_ref(obj);
473 return creds;
474 }
475
setup_address_and_port(const char ** address,const char ** port)476 static void setup_address_and_port(const char **address, const char **port)
477 {
478 if (*address == NULL) {
479 *address = "0.0.0.0";
480 }
481
482 if (*port == NULL) {
483 *port = stringify(NBD_DEFAULT_PORT);
484 }
485 }
486
487 /*
488 * Check socket parameters compatibility when socket activation is used.
489 */
socket_activation_validate_opts(const char * device,const char * sockpath,const char * address,const char * port,const char * selinux,bool list)490 static const char *socket_activation_validate_opts(const char *device,
491 const char *sockpath,
492 const char *address,
493 const char *port,
494 const char *selinux,
495 bool list)
496 {
497 if (device != NULL) {
498 return "NBD device can't be set when using socket activation";
499 }
500
501 if (sockpath != NULL) {
502 return "Unix socket can't be set when using socket activation";
503 }
504
505 if (address != NULL) {
506 return "The interface can't be set when using socket activation";
507 }
508
509 if (port != NULL) {
510 return "TCP port number can't be set when using socket activation";
511 }
512
513 if (selinux != NULL) {
514 return "SELinux label can't be set when using socket activation";
515 }
516
517 if (list) {
518 return "List mode is incompatible with socket activation";
519 }
520
521 return NULL;
522 }
523
qemu_nbd_shutdown(void)524 static void qemu_nbd_shutdown(void)
525 {
526 job_cancel_sync_all();
527 blk_exp_close_all();
528 bdrv_close_all();
529 }
530
main(int argc,char ** argv)531 int main(int argc, char **argv)
532 {
533 BlockBackend *blk;
534 BlockDriverState *bs;
535 uint64_t dev_offset = 0;
536 bool readonly = false;
537 bool disconnect = false;
538 const char *bindto = NULL;
539 const char *port = NULL;
540 char *sockpath = NULL;
541 QemuOpts *sn_opts = NULL;
542 const char *sn_id_or_name = NULL;
543 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
544 struct option lopt[] = {
545 { "help", no_argument, NULL, 'h' },
546 { "version", no_argument, NULL, 'V' },
547 { "bind", required_argument, NULL, 'b' },
548 { "port", required_argument, NULL, 'p' },
549 { "socket", required_argument, NULL, 'k' },
550 { "offset", required_argument, NULL, 'o' },
551 { "read-only", no_argument, NULL, 'r' },
552 { "allocation-depth", no_argument, NULL, 'A' },
553 { "bitmap", required_argument, NULL, 'B' },
554 { "connect", required_argument, NULL, 'c' },
555 { "disconnect", no_argument, NULL, 'd' },
556 { "list", no_argument, NULL, 'L' },
557 { "snapshot", no_argument, NULL, 's' },
558 { "load-snapshot", required_argument, NULL, 'l' },
559 { "nocache", no_argument, NULL, 'n' },
560 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
561 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
562 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
563 { "detect-zeroes", required_argument, NULL,
564 QEMU_NBD_OPT_DETECT_ZEROES },
565 { "shared", required_argument, NULL, 'e' },
566 { "format", required_argument, NULL, 'f' },
567 { "persistent", no_argument, NULL, 't' },
568 { "verbose", no_argument, NULL, 'v' },
569 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
570 { "export-name", required_argument, NULL, 'x' },
571 { "description", required_argument, NULL, 'D' },
572 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
573 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME },
574 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
575 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
576 { "trace", required_argument, NULL, 'T' },
577 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
578 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
579 { "selinux-label", required_argument, NULL,
580 QEMU_NBD_OPT_SELINUX_LABEL },
581 { NULL, 0, NULL, 0 }
582 };
583 int ch;
584 int opt_ind = 0;
585 int flags = BDRV_O_RDWR;
586 int ret = 0;
587 bool seen_cache = false;
588 bool seen_discard = false;
589 bool seen_aio = false;
590 pthread_t client_thread;
591 const char *fmt = NULL;
592 Error *local_err = NULL;
593 BlockdevDetectZeroesOptions detect_zeroes =
594 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
595 QDict *options = NULL;
596 const char *export_name = NULL; /* defaults to "" later for server mode */
597 const char *export_description = NULL;
598 BlockDirtyBitmapOrStrList *bitmaps = NULL;
599 bool alloc_depth = false;
600 const char *tlscredsid = NULL;
601 const char *tlshostname = NULL;
602 bool imageOpts = false;
603 bool writethrough = false; /* Client will flush as needed. */
604 bool list = false;
605 unsigned socket_activation;
606 const char *pid_file_name = NULL;
607 const char *selinux_label = NULL;
608 BlockExportOptions *export_opts;
609 struct NbdClientOpts opts = {
610 .fork_process = false,
611 .verbose = false,
612 .device = NULL,
613 .srcpath = NULL,
614 .saddr = NULL,
615 .old_stderr = STDOUT_FILENO,
616 };
617
618 #ifdef CONFIG_POSIX
619 os_setup_early_signal_handling();
620 os_setup_signal_handling();
621 #endif
622
623 socket_init();
624 error_init(argv[0]);
625 module_call_init(MODULE_INIT_TRACE);
626 qcrypto_init(&error_fatal);
627
628 module_call_init(MODULE_INIT_QOM);
629 qemu_add_opts(&qemu_trace_opts);
630 qemu_init_exec_dir(argv[0]);
631
632 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
633 switch (ch) {
634 case 's':
635 flags |= BDRV_O_SNAPSHOT;
636 break;
637 case 'n':
638 optarg = (char *) "none";
639 /* fallthrough */
640 case QEMU_NBD_OPT_CACHE:
641 if (seen_cache) {
642 error_report("-n and --cache can only be specified once");
643 exit(EXIT_FAILURE);
644 }
645 seen_cache = true;
646 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
647 error_report("Invalid cache mode `%s'", optarg);
648 exit(EXIT_FAILURE);
649 }
650 break;
651 case QEMU_NBD_OPT_AIO:
652 if (seen_aio) {
653 error_report("--aio can only be specified once");
654 exit(EXIT_FAILURE);
655 }
656 seen_aio = true;
657 if (bdrv_parse_aio(optarg, &flags) < 0) {
658 error_report("Invalid aio mode '%s'", optarg);
659 exit(EXIT_FAILURE);
660 }
661 break;
662 case QEMU_NBD_OPT_DISCARD:
663 if (seen_discard) {
664 error_report("--discard can only be specified once");
665 exit(EXIT_FAILURE);
666 }
667 seen_discard = true;
668 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
669 error_report("Invalid discard mode `%s'", optarg);
670 exit(EXIT_FAILURE);
671 }
672 break;
673 case QEMU_NBD_OPT_DETECT_ZEROES:
674 detect_zeroes =
675 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
676 optarg,
677 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
678 &local_err);
679 if (local_err) {
680 error_reportf_err(local_err,
681 "Failed to parse detect_zeroes mode: ");
682 exit(EXIT_FAILURE);
683 }
684 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
685 !(flags & BDRV_O_UNMAP)) {
686 error_report("setting detect-zeroes to unmap is not allowed "
687 "without setting discard operation to unmap");
688 exit(EXIT_FAILURE);
689 }
690 break;
691 case 'b':
692 bindto = optarg;
693 break;
694 case 'p':
695 port = optarg;
696 break;
697 case 'o':
698 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
699 error_report("Invalid offset '%s'", optarg);
700 exit(EXIT_FAILURE);
701 }
702 break;
703 case 'l':
704 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
705 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
706 optarg, false);
707 if (!sn_opts) {
708 error_report("Failed in parsing snapshot param `%s'",
709 optarg);
710 exit(EXIT_FAILURE);
711 }
712 } else {
713 sn_id_or_name = optarg;
714 }
715 /* fall through */
716 case 'r':
717 readonly = true;
718 flags &= ~BDRV_O_RDWR;
719 break;
720 case 'A':
721 alloc_depth = true;
722 break;
723 case 'B':
724 {
725 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1);
726 *el = (BlockDirtyBitmapOrStr) {
727 .type = QTYPE_QSTRING,
728 .u.local = g_strdup(optarg),
729 };
730 QAPI_LIST_PREPEND(bitmaps, el);
731 }
732 break;
733 case 'k':
734 sockpath = optarg;
735 if (sockpath[0] != '/') {
736 error_report("socket path must be absolute");
737 exit(EXIT_FAILURE);
738 }
739 break;
740 case 'd':
741 disconnect = true;
742 break;
743 case 'c':
744 opts.device = optarg;
745 break;
746 case 'e':
747 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
748 shared < 0) {
749 error_report("Invalid shared device number '%s'", optarg);
750 exit(EXIT_FAILURE);
751 }
752 break;
753 case 'f':
754 fmt = optarg;
755 break;
756 case 't':
757 persistent = 1;
758 break;
759 case 'x':
760 export_name = optarg;
761 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
762 error_report("export name '%s' too long", export_name);
763 exit(EXIT_FAILURE);
764 }
765 break;
766 case 'D':
767 export_description = optarg;
768 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
769 error_report("export description '%s' too long",
770 export_description);
771 exit(EXIT_FAILURE);
772 }
773 break;
774 case 'v':
775 opts.verbose = true;
776 break;
777 case 'V':
778 version(argv[0]);
779 exit(0);
780 break;
781 case 'h':
782 usage(argv[0]);
783 exit(0);
784 break;
785 case '?':
786 error_report("Try `%s --help' for more information.", argv[0]);
787 exit(EXIT_FAILURE);
788 case QEMU_NBD_OPT_OBJECT:
789 user_creatable_process_cmdline(optarg);
790 break;
791 case QEMU_NBD_OPT_TLSCREDS:
792 tlscredsid = optarg;
793 break;
794 case QEMU_NBD_OPT_TLSHOSTNAME:
795 tlshostname = optarg;
796 break;
797 case QEMU_NBD_OPT_IMAGE_OPTS:
798 imageOpts = true;
799 break;
800 case 'T':
801 trace_opt_parse(optarg);
802 break;
803 case QEMU_NBD_OPT_TLSAUTHZ:
804 tlsauthz = optarg;
805 break;
806 case QEMU_NBD_OPT_FORK:
807 opts.fork_process = true;
808 break;
809 case 'L':
810 list = true;
811 break;
812 case QEMU_NBD_OPT_PID_FILE:
813 pid_file_name = optarg;
814 break;
815 case QEMU_NBD_OPT_SELINUX_LABEL:
816 selinux_label = optarg;
817 break;
818 }
819 }
820
821 if (list) {
822 if (argc != optind) {
823 error_report("List mode is incompatible with a file name");
824 exit(EXIT_FAILURE);
825 }
826 if (export_name || export_description || dev_offset ||
827 opts.device || disconnect || fmt || sn_id_or_name || bitmaps ||
828 alloc_depth || seen_aio || seen_discard || seen_cache) {
829 error_report("List mode is incompatible with per-device settings");
830 exit(EXIT_FAILURE);
831 }
832 if (opts.fork_process) {
833 error_report("List mode is incompatible with forking");
834 exit(EXIT_FAILURE);
835 }
836 } else if ((argc - optind) != 1) {
837 error_report("Invalid number of arguments");
838 error_printf("Try `%s --help' for more information.\n", argv[0]);
839 exit(EXIT_FAILURE);
840 } else if (!export_name) {
841 export_name = "";
842 }
843
844 if (!trace_init_backends()) {
845 exit(1);
846 }
847 trace_init_file();
848 qemu_set_log(LOG_TRACE, &error_fatal);
849
850 socket_activation = check_socket_activation();
851 if (socket_activation == 0) {
852 if (!sockpath) {
853 setup_address_and_port(&bindto, &port);
854 }
855 } else {
856 /* Using socket activation - check user didn't use -p etc. */
857 const char *err_msg = socket_activation_validate_opts(opts.device,
858 sockpath,
859 bindto, port,
860 selinux_label,
861 list);
862 if (err_msg != NULL) {
863 error_report("%s", err_msg);
864 exit(EXIT_FAILURE);
865 }
866
867 /* qemu-nbd can only listen on a single socket. */
868 if (socket_activation > 1) {
869 error_report("qemu-nbd does not support socket activation with %s > 1",
870 "LISTEN_FDS");
871 exit(EXIT_FAILURE);
872 }
873 }
874
875 if (tlscredsid) {
876 if (opts.device) {
877 error_report("TLS is not supported with a host device");
878 exit(EXIT_FAILURE);
879 }
880 if (tlsauthz && list) {
881 error_report("TLS authorization is incompatible with export list");
882 exit(EXIT_FAILURE);
883 }
884 if (tlshostname && !list) {
885 error_report("TLS hostname is only supported with export list");
886 exit(EXIT_FAILURE);
887 }
888 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
889 if (local_err) {
890 error_reportf_err(local_err, "Failed to get TLS creds: ");
891 exit(EXIT_FAILURE);
892 }
893 } else {
894 if (tlsauthz) {
895 error_report("--tls-authz is not permitted without --tls-creds");
896 exit(EXIT_FAILURE);
897 }
898 if (tlshostname) {
899 error_report("--tls-hostname is not permitted without --tls-creds");
900 exit(EXIT_FAILURE);
901 }
902 }
903
904 if (selinux_label) {
905 #ifdef CONFIG_SELINUX
906 if (sockpath == NULL && opts.device == NULL) {
907 error_report("--selinux-label is not permitted without --socket");
908 exit(EXIT_FAILURE);
909 }
910 #else
911 error_report("SELinux support not enabled in this binary");
912 exit(EXIT_FAILURE);
913 #endif
914 }
915
916 if (list) {
917 opts.saddr = nbd_build_socket_address(sockpath, bindto, port);
918 return qemu_nbd_client_list(opts.saddr, tlscreds,
919 tlshostname ? tlshostname : bindto);
920 }
921
922 #if !HAVE_NBD_DEVICE
923 if (disconnect || opts.device) {
924 error_report("Kernel /dev/nbdN support not available");
925 exit(EXIT_FAILURE);
926 }
927 #else /* HAVE_NBD_DEVICE */
928 if (disconnect) {
929 int nbdfd = open(argv[optind], O_RDWR);
930 if (nbdfd < 0) {
931 error_report("Cannot open %s: %s", argv[optind],
932 strerror(errno));
933 exit(EXIT_FAILURE);
934 }
935 nbd_disconnect(nbdfd);
936
937 close(nbdfd);
938
939 printf("%s disconnected\n", argv[optind]);
940
941 return 0;
942 }
943 #endif
944
945 if ((opts.device && !opts.verbose) || opts.fork_process) {
946 #ifndef WIN32
947 g_autoptr(GError) err = NULL;
948 int stderr_fd[2];
949 pid_t pid;
950
951 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) {
952 error_report("Error setting up communication pipe: %s",
953 err->message);
954 exit(EXIT_FAILURE);
955 }
956
957 /* Now daemonize, but keep a communication channel open to
958 * print errors and exit with the proper status code.
959 */
960 pid = fork();
961 if (pid < 0) {
962 error_report("Failed to fork: %s", strerror(errno));
963 exit(EXIT_FAILURE);
964 } else if (pid == 0) {
965 int saved_errno;
966
967 close(stderr_fd[0]);
968
969 /* Remember parent's stderr if we will be restoring it. */
970 if (opts.verbose /* fork_process is set */) {
971 opts.old_stderr = dup(STDERR_FILENO);
972 if (opts.old_stderr < 0) {
973 error_report("Could not dup original stderr: %s",
974 strerror(errno));
975 exit(EXIT_FAILURE);
976 }
977 }
978
979 ret = qemu_daemon(1, 0);
980 saved_errno = errno; /* dup2 will overwrite error below */
981
982 /* Temporarily redirect stderr to the parent's pipe... */
983 if (dup2(stderr_fd[1], STDERR_FILENO) < 0) {
984 char str[256];
985 snprintf(str, sizeof(str),
986 "%s: Failed to link stderr to the pipe: %s\n",
987 g_get_prgname(), strerror(errno));
988 /*
989 * We are unable to use error_report() here as we need to get
990 * stderr pointed to the parent's pipe. Write to that pipe
991 * manually.
992 */
993 ret = write(stderr_fd[1], str, strlen(str));
994 exit(EXIT_FAILURE);
995 }
996
997 if (ret < 0) {
998 error_report("Failed to daemonize: %s", strerror(saved_errno));
999 exit(EXIT_FAILURE);
1000 }
1001
1002 /* ... close the descriptor we inherited and go on. */
1003 close(stderr_fd[1]);
1004 } else {
1005 bool errors = false;
1006 char *buf;
1007
1008 /* In the parent. Print error messages from the child until
1009 * it closes the pipe.
1010 */
1011 close(stderr_fd[1]);
1012 buf = g_malloc(1024);
1013 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
1014 errors = true;
1015 ret = qemu_write_full(STDERR_FILENO, buf, ret);
1016 if (ret < 0) {
1017 exit(EXIT_FAILURE);
1018 }
1019 }
1020 if (ret < 0) {
1021 error_report("Cannot read from daemon: %s",
1022 strerror(errno));
1023 exit(EXIT_FAILURE);
1024 }
1025
1026 /* Usually the daemon should not print any message.
1027 * Exit with zero status in that case.
1028 */
1029 exit(errors);
1030 }
1031 #else /* WIN32 */
1032 error_report("Unable to fork into background on Windows hosts");
1033 exit(EXIT_FAILURE);
1034 #endif /* WIN32 */
1035 }
1036
1037 if (opts.device != NULL && sockpath == NULL) {
1038 sockpath = g_malloc(128);
1039 snprintf(sockpath, 128, SOCKET_PATH, basename(opts.device));
1040 }
1041
1042 server = qio_net_listener_new();
1043 if (socket_activation == 0) {
1044 int backlog;
1045
1046 if (persistent || shared == 0) {
1047 backlog = SOMAXCONN;
1048 } else {
1049 backlog = MIN(shared, SOMAXCONN);
1050 }
1051 #ifdef CONFIG_SELINUX
1052 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) {
1053 error_report("Cannot set SELinux socket create context to %s: %s",
1054 selinux_label, strerror(errno));
1055 exit(EXIT_FAILURE);
1056 }
1057 #endif
1058 opts.saddr = nbd_build_socket_address(sockpath, bindto, port);
1059 if (qio_net_listener_open_sync(server, opts.saddr, backlog,
1060 &local_err) < 0) {
1061 object_unref(OBJECT(server));
1062 error_report_err(local_err);
1063 exit(EXIT_FAILURE);
1064 }
1065 #ifdef CONFIG_SELINUX
1066 if (selinux_label && setsockcreatecon_raw(NULL) == -1) {
1067 error_report("Cannot clear SELinux socket create context: %s",
1068 strerror(errno));
1069 exit(EXIT_FAILURE);
1070 }
1071 #endif
1072 } else {
1073 size_t i;
1074 /* See comment in check_socket_activation above. */
1075 for (i = 0; i < socket_activation; i++) {
1076 QIOChannelSocket *sioc;
1077 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1078 &local_err);
1079 if (sioc == NULL) {
1080 object_unref(OBJECT(server));
1081 error_reportf_err(local_err,
1082 "Failed to use socket activation: ");
1083 exit(EXIT_FAILURE);
1084 }
1085 qio_net_listener_add(server, sioc);
1086 object_unref(OBJECT(sioc));
1087 }
1088 }
1089
1090 qemu_init_main_loop(&error_fatal);
1091 bdrv_init();
1092 atexit(qemu_nbd_shutdown);
1093
1094 opts.srcpath = argv[optind];
1095 if (imageOpts) {
1096 QemuOpts *o;
1097 if (fmt) {
1098 error_report("--image-opts and -f are mutually exclusive");
1099 exit(EXIT_FAILURE);
1100 }
1101 o = qemu_opts_parse_noisily(&file_opts, opts.srcpath, true);
1102 if (!o) {
1103 qemu_opts_reset(&file_opts);
1104 exit(EXIT_FAILURE);
1105 }
1106 options = qemu_opts_to_qdict(o, NULL);
1107 qemu_opts_reset(&file_opts);
1108 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1109 } else {
1110 if (fmt) {
1111 options = qdict_new();
1112 qdict_put_str(options, "driver", fmt);
1113 }
1114 blk = blk_new_open(opts.srcpath, NULL, options, flags, &local_err);
1115 }
1116
1117 if (!blk) {
1118 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1119 argv[optind]);
1120 exit(EXIT_FAILURE);
1121 }
1122 bs = blk_bs(blk);
1123
1124 if (dev_offset) {
1125 QDict *raw_opts = qdict_new();
1126 qdict_put_str(raw_opts, "driver", "raw");
1127 qdict_put_str(raw_opts, "file", bs->node_name);
1128 qdict_put_int(raw_opts, "offset", dev_offset);
1129
1130 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1131
1132 blk_remove_bs(blk);
1133 blk_insert_bs(blk, bs, &error_fatal);
1134 bdrv_unref(bs);
1135 }
1136
1137 blk_set_enable_write_cache(blk, !writethrough);
1138
1139 if (sn_opts) {
1140 ret = bdrv_snapshot_load_tmp(bs,
1141 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1142 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1143 &local_err);
1144 } else if (sn_id_or_name) {
1145 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1146 &local_err);
1147 }
1148 if (ret < 0) {
1149 error_reportf_err(local_err, "Failed to load snapshot: ");
1150 exit(EXIT_FAILURE);
1151 }
1152
1153 bs->detect_zeroes = detect_zeroes;
1154
1155 nbd_server_is_qemu_nbd(shared);
1156
1157 export_opts = g_new(BlockExportOptions, 1);
1158 *export_opts = (BlockExportOptions) {
1159 .type = BLOCK_EXPORT_TYPE_NBD,
1160 .id = g_strdup("qemu-nbd-export"),
1161 .node_name = g_strdup(bdrv_get_node_name(bs)),
1162 .has_writethrough = true,
1163 .writethrough = writethrough,
1164 .has_writable = true,
1165 .writable = !readonly,
1166 .u.nbd = {
1167 .name = g_strdup(export_name),
1168 .description = g_strdup(export_description),
1169 .has_bitmaps = !!bitmaps,
1170 .bitmaps = bitmaps,
1171 .has_allocation_depth = alloc_depth,
1172 .allocation_depth = alloc_depth,
1173 },
1174 };
1175 blk_exp_add(export_opts, &error_fatal);
1176 qapi_free_BlockExportOptions(export_opts);
1177
1178 if (opts.device) {
1179 #if HAVE_NBD_DEVICE
1180 ret = pthread_create(&client_thread, NULL, nbd_client_thread, &opts);
1181 if (ret != 0) {
1182 error_report("Failed to create client thread: %s", strerror(ret));
1183 exit(EXIT_FAILURE);
1184 }
1185 #endif
1186 } else {
1187 /* Shut up GCC warnings. */
1188 memset(&client_thread, 0, sizeof(client_thread));
1189 }
1190
1191 nbd_update_server_watch();
1192
1193 if (pid_file_name) {
1194 qemu_write_pidfile(pid_file_name, &error_fatal);
1195 }
1196
1197 /* now when the initialization is (almost) complete, chdir("/")
1198 * to free any busy filesystems */
1199 if (chdir("/") < 0) {
1200 error_report("Could not chdir to root directory: %s",
1201 strerror(errno));
1202 exit(EXIT_FAILURE);
1203 }
1204
1205 if (opts.fork_process) {
1206 nbd_client_release_pipe(opts.old_stderr);
1207 }
1208
1209 state = RUNNING;
1210 do {
1211 main_loop_wait(false);
1212 if (state == TERMINATE) {
1213 blk_exp_close_all();
1214 state = TERMINATED;
1215 }
1216 } while (state != TERMINATED);
1217
1218 blk_unref(blk);
1219 if (sockpath) {
1220 unlink(sockpath);
1221 }
1222
1223 qemu_opts_del(sn_opts);
1224
1225 if (opts.device) {
1226 void *result;
1227 pthread_join(client_thread, &result);
1228 ret = (intptr_t)result;
1229 exit(ret);
1230 } else {
1231 exit(EXIT_SUCCESS);
1232 }
1233 }
1234