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 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
394 }
395
nbd_update_server_watch(void)396 static void nbd_update_server_watch(void)
397 {
398 if (nbd_can_accept()) {
399 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
400 } else {
401 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
402 }
403 }
404
405
nbd_build_socket_address(const char * sockpath,const char * bindto,const char * port)406 static SocketAddress *nbd_build_socket_address(const char *sockpath,
407 const char *bindto,
408 const char *port)
409 {
410 SocketAddress *saddr;
411
412 saddr = g_new0(SocketAddress, 1);
413 if (sockpath) {
414 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
415 saddr->u.q_unix.path = g_strdup(sockpath);
416 } else {
417 InetSocketAddress *inet;
418 saddr->type = SOCKET_ADDRESS_TYPE_INET;
419 inet = &saddr->u.inet;
420 inet->host = g_strdup(bindto);
421 if (port) {
422 inet->port = g_strdup(port);
423 } else {
424 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
425 }
426 }
427
428 return saddr;
429 }
430
431
432 static QemuOptsList file_opts = {
433 .name = "file",
434 .implied_opt_name = "file",
435 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
436 .desc = {
437 /* no elements => accept any params */
438 { /* end of list */ }
439 },
440 };
441
nbd_get_tls_creds(const char * id,bool list,Error ** errp)442 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
443 Error **errp)
444 {
445 Object *obj;
446 QCryptoTLSCreds *creds;
447
448 obj = object_resolve_path_component(
449 object_get_objects_root(), id);
450 if (!obj) {
451 error_setg(errp, "No TLS credentials with id '%s'",
452 id);
453 return NULL;
454 }
455 creds = (QCryptoTLSCreds *)
456 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
457 if (!creds) {
458 error_setg(errp, "Object with id '%s' is not TLS credentials",
459 id);
460 return NULL;
461 }
462
463 if (!qcrypto_tls_creds_check_endpoint(creds,
464 list
465 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT
466 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
467 errp)) {
468 return NULL;
469 }
470 object_ref(obj);
471 return creds;
472 }
473
setup_address_and_port(const char ** address,const char ** port)474 static void setup_address_and_port(const char **address, const char **port)
475 {
476 if (*address == NULL) {
477 *address = "0.0.0.0";
478 }
479
480 if (*port == NULL) {
481 *port = stringify(NBD_DEFAULT_PORT);
482 }
483 }
484
485 /*
486 * Check socket parameters compatibility when socket activation is used.
487 */
socket_activation_validate_opts(const char * device,const char * sockpath,const char * address,const char * port,const char * selinux,bool list)488 static const char *socket_activation_validate_opts(const char *device,
489 const char *sockpath,
490 const char *address,
491 const char *port,
492 const char *selinux,
493 bool list)
494 {
495 if (device != NULL) {
496 return "NBD device can't be set when using socket activation";
497 }
498
499 if (sockpath != NULL) {
500 return "Unix socket can't be set when using socket activation";
501 }
502
503 if (address != NULL) {
504 return "The interface can't be set when using socket activation";
505 }
506
507 if (port != NULL) {
508 return "TCP port number can't be set when using socket activation";
509 }
510
511 if (selinux != NULL) {
512 return "SELinux label can't be set when using socket activation";
513 }
514
515 if (list) {
516 return "List mode is incompatible with socket activation";
517 }
518
519 return NULL;
520 }
521
qemu_nbd_shutdown(void)522 static void qemu_nbd_shutdown(void)
523 {
524 job_cancel_sync_all();
525 blk_exp_close_all();
526 bdrv_close_all();
527 }
528
main(int argc,char ** argv)529 int main(int argc, char **argv)
530 {
531 BlockBackend *blk;
532 BlockDriverState *bs;
533 uint64_t dev_offset = 0;
534 bool readonly = false;
535 bool disconnect = false;
536 const char *bindto = NULL;
537 const char *port = NULL;
538 char *sockpath = NULL;
539 QemuOpts *sn_opts = NULL;
540 const char *sn_id_or_name = NULL;
541 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
542 struct option lopt[] = {
543 { "help", no_argument, NULL, 'h' },
544 { "version", no_argument, NULL, 'V' },
545 { "bind", required_argument, NULL, 'b' },
546 { "port", required_argument, NULL, 'p' },
547 { "socket", required_argument, NULL, 'k' },
548 { "offset", required_argument, NULL, 'o' },
549 { "read-only", no_argument, NULL, 'r' },
550 { "allocation-depth", no_argument, NULL, 'A' },
551 { "bitmap", required_argument, NULL, 'B' },
552 { "connect", required_argument, NULL, 'c' },
553 { "disconnect", no_argument, NULL, 'd' },
554 { "list", no_argument, NULL, 'L' },
555 { "snapshot", no_argument, NULL, 's' },
556 { "load-snapshot", required_argument, NULL, 'l' },
557 { "nocache", no_argument, NULL, 'n' },
558 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
559 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
560 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
561 { "detect-zeroes", required_argument, NULL,
562 QEMU_NBD_OPT_DETECT_ZEROES },
563 { "shared", required_argument, NULL, 'e' },
564 { "format", required_argument, NULL, 'f' },
565 { "persistent", no_argument, NULL, 't' },
566 { "verbose", no_argument, NULL, 'v' },
567 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
568 { "export-name", required_argument, NULL, 'x' },
569 { "description", required_argument, NULL, 'D' },
570 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
571 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME },
572 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
573 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
574 { "trace", required_argument, NULL, 'T' },
575 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
576 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
577 { "selinux-label", required_argument, NULL,
578 QEMU_NBD_OPT_SELINUX_LABEL },
579 { NULL, 0, NULL, 0 }
580 };
581 int ch;
582 int opt_ind = 0;
583 int flags = BDRV_O_RDWR;
584 int ret = 0;
585 bool seen_cache = false;
586 bool seen_discard = false;
587 bool seen_aio = false;
588 pthread_t client_thread;
589 const char *fmt = NULL;
590 Error *local_err = NULL;
591 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
592 QDict *options = NULL;
593 const char *export_name = NULL; /* defaults to "" later for server mode */
594 const char *export_description = NULL;
595 BlockDirtyBitmapOrStrList *bitmaps = NULL;
596 bool alloc_depth = false;
597 const char *tlscredsid = NULL;
598 const char *tlshostname = NULL;
599 bool imageOpts = false;
600 bool writethrough = false; /* Client will flush as needed. */
601 bool list = false;
602 unsigned socket_activation;
603 const char *pid_file_name = NULL;
604 const char *selinux_label = NULL;
605 BlockExportOptions *export_opts;
606 struct NbdClientOpts opts = {
607 .fork_process = false,
608 .verbose = false,
609 .device = NULL,
610 .srcpath = NULL,
611 .saddr = NULL,
612 .old_stderr = STDOUT_FILENO,
613 };
614
615 #ifdef CONFIG_POSIX
616 os_setup_early_signal_handling();
617 os_setup_signal_handling();
618 #endif
619
620 socket_init();
621 error_init(argv[0]);
622 module_call_init(MODULE_INIT_TRACE);
623 qcrypto_init(&error_fatal);
624
625 module_call_init(MODULE_INIT_QOM);
626 qemu_add_opts(&qemu_trace_opts);
627 qemu_init_exec_dir(argv[0]);
628
629 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
630 switch (ch) {
631 case 's':
632 flags |= BDRV_O_SNAPSHOT;
633 break;
634 case 'n':
635 optarg = (char *) "none";
636 /* fallthrough */
637 case QEMU_NBD_OPT_CACHE:
638 if (seen_cache) {
639 error_report("-n and --cache can only be specified once");
640 exit(EXIT_FAILURE);
641 }
642 seen_cache = true;
643 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
644 error_report("Invalid cache mode `%s'", optarg);
645 exit(EXIT_FAILURE);
646 }
647 break;
648 case QEMU_NBD_OPT_AIO:
649 if (seen_aio) {
650 error_report("--aio can only be specified once");
651 exit(EXIT_FAILURE);
652 }
653 seen_aio = true;
654 if (bdrv_parse_aio(optarg, &flags) < 0) {
655 error_report("Invalid aio mode '%s'", optarg);
656 exit(EXIT_FAILURE);
657 }
658 break;
659 case QEMU_NBD_OPT_DISCARD:
660 if (seen_discard) {
661 error_report("--discard can only be specified once");
662 exit(EXIT_FAILURE);
663 }
664 seen_discard = true;
665 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
666 error_report("Invalid discard mode `%s'", optarg);
667 exit(EXIT_FAILURE);
668 }
669 break;
670 case QEMU_NBD_OPT_DETECT_ZEROES:
671 detect_zeroes =
672 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
673 optarg,
674 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
675 &local_err);
676 if (local_err) {
677 error_reportf_err(local_err,
678 "Failed to parse detect_zeroes mode: ");
679 exit(EXIT_FAILURE);
680 }
681 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
682 !(flags & BDRV_O_UNMAP)) {
683 error_report("setting detect-zeroes to unmap is not allowed "
684 "without setting discard operation to unmap");
685 exit(EXIT_FAILURE);
686 }
687 break;
688 case 'b':
689 bindto = optarg;
690 break;
691 case 'p':
692 port = optarg;
693 break;
694 case 'o':
695 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
696 error_report("Invalid offset '%s'", optarg);
697 exit(EXIT_FAILURE);
698 }
699 break;
700 case 'l':
701 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
702 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
703 optarg, false);
704 if (!sn_opts) {
705 error_report("Failed in parsing snapshot param `%s'",
706 optarg);
707 exit(EXIT_FAILURE);
708 }
709 } else {
710 sn_id_or_name = optarg;
711 }
712 /* fall through */
713 case 'r':
714 readonly = true;
715 flags &= ~BDRV_O_RDWR;
716 break;
717 case 'A':
718 alloc_depth = true;
719 break;
720 case 'B':
721 {
722 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1);
723 *el = (BlockDirtyBitmapOrStr) {
724 .type = QTYPE_QSTRING,
725 .u.local = g_strdup(optarg),
726 };
727 QAPI_LIST_PREPEND(bitmaps, el);
728 }
729 break;
730 case 'k':
731 sockpath = optarg;
732 if (sockpath[0] != '/') {
733 error_report("socket path must be absolute");
734 exit(EXIT_FAILURE);
735 }
736 break;
737 case 'd':
738 disconnect = true;
739 break;
740 case 'c':
741 opts.device = optarg;
742 break;
743 case 'e':
744 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
745 shared < 0) {
746 error_report("Invalid shared device number '%s'", optarg);
747 exit(EXIT_FAILURE);
748 }
749 break;
750 case 'f':
751 fmt = optarg;
752 break;
753 case 't':
754 persistent = 1;
755 break;
756 case 'x':
757 export_name = optarg;
758 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
759 error_report("export name '%s' too long", export_name);
760 exit(EXIT_FAILURE);
761 }
762 break;
763 case 'D':
764 export_description = optarg;
765 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
766 error_report("export description '%s' too long",
767 export_description);
768 exit(EXIT_FAILURE);
769 }
770 break;
771 case 'v':
772 opts.verbose = true;
773 break;
774 case 'V':
775 version(argv[0]);
776 exit(0);
777 break;
778 case 'h':
779 usage(argv[0]);
780 exit(0);
781 break;
782 case '?':
783 error_report("Try `%s --help' for more information.", argv[0]);
784 exit(EXIT_FAILURE);
785 case QEMU_NBD_OPT_OBJECT:
786 user_creatable_process_cmdline(optarg);
787 break;
788 case QEMU_NBD_OPT_TLSCREDS:
789 tlscredsid = optarg;
790 break;
791 case QEMU_NBD_OPT_TLSHOSTNAME:
792 tlshostname = optarg;
793 break;
794 case QEMU_NBD_OPT_IMAGE_OPTS:
795 imageOpts = true;
796 break;
797 case 'T':
798 trace_opt_parse(optarg);
799 break;
800 case QEMU_NBD_OPT_TLSAUTHZ:
801 tlsauthz = optarg;
802 break;
803 case QEMU_NBD_OPT_FORK:
804 opts.fork_process = true;
805 break;
806 case 'L':
807 list = true;
808 break;
809 case QEMU_NBD_OPT_PID_FILE:
810 pid_file_name = optarg;
811 break;
812 case QEMU_NBD_OPT_SELINUX_LABEL:
813 selinux_label = optarg;
814 break;
815 }
816 }
817
818 if (list) {
819 if (argc != optind) {
820 error_report("List mode is incompatible with a file name");
821 exit(EXIT_FAILURE);
822 }
823 if (export_name || export_description || dev_offset ||
824 opts.device || disconnect || fmt || sn_id_or_name || bitmaps ||
825 alloc_depth || seen_aio || seen_discard || seen_cache) {
826 error_report("List mode is incompatible with per-device settings");
827 exit(EXIT_FAILURE);
828 }
829 if (opts.fork_process) {
830 error_report("List mode is incompatible with forking");
831 exit(EXIT_FAILURE);
832 }
833 } else if ((argc - optind) != 1) {
834 error_report("Invalid number of arguments");
835 error_printf("Try `%s --help' for more information.\n", argv[0]);
836 exit(EXIT_FAILURE);
837 } else if (!export_name) {
838 export_name = "";
839 }
840
841 if (!trace_init_backends()) {
842 exit(1);
843 }
844 trace_init_file();
845 qemu_set_log(LOG_TRACE, &error_fatal);
846
847 socket_activation = check_socket_activation();
848 if (socket_activation == 0) {
849 if (!sockpath) {
850 setup_address_and_port(&bindto, &port);
851 }
852 } else {
853 /* Using socket activation - check user didn't use -p etc. */
854 const char *err_msg = socket_activation_validate_opts(opts.device,
855 sockpath,
856 bindto, port,
857 selinux_label,
858 list);
859 if (err_msg != NULL) {
860 error_report("%s", err_msg);
861 exit(EXIT_FAILURE);
862 }
863
864 /* qemu-nbd can only listen on a single socket. */
865 if (socket_activation > 1) {
866 error_report("qemu-nbd does not support socket activation with %s > 1",
867 "LISTEN_FDS");
868 exit(EXIT_FAILURE);
869 }
870 }
871
872 if (tlscredsid) {
873 if (opts.device) {
874 error_report("TLS is not supported with a host device");
875 exit(EXIT_FAILURE);
876 }
877 if (tlsauthz && list) {
878 error_report("TLS authorization is incompatible with export list");
879 exit(EXIT_FAILURE);
880 }
881 if (tlshostname && !list) {
882 error_report("TLS hostname is only supported with export list");
883 exit(EXIT_FAILURE);
884 }
885 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
886 if (local_err) {
887 error_reportf_err(local_err, "Failed to get TLS creds: ");
888 exit(EXIT_FAILURE);
889 }
890 } else {
891 if (tlsauthz) {
892 error_report("--tls-authz is not permitted without --tls-creds");
893 exit(EXIT_FAILURE);
894 }
895 if (tlshostname) {
896 error_report("--tls-hostname is not permitted without --tls-creds");
897 exit(EXIT_FAILURE);
898 }
899 }
900
901 if (selinux_label) {
902 #ifdef CONFIG_SELINUX
903 if (sockpath == NULL && opts.device == NULL) {
904 error_report("--selinux-label is not permitted without --socket");
905 exit(EXIT_FAILURE);
906 }
907 #else
908 error_report("SELinux support not enabled in this binary");
909 exit(EXIT_FAILURE);
910 #endif
911 }
912
913 if (list) {
914 opts.saddr = nbd_build_socket_address(sockpath, bindto, port);
915 return qemu_nbd_client_list(opts.saddr, tlscreds,
916 tlshostname ? tlshostname : bindto);
917 }
918
919 #if !HAVE_NBD_DEVICE
920 if (disconnect || opts.device) {
921 error_report("Kernel /dev/nbdN support not available");
922 exit(EXIT_FAILURE);
923 }
924 #else /* HAVE_NBD_DEVICE */
925 if (disconnect) {
926 int nbdfd = open(argv[optind], O_RDWR);
927 if (nbdfd < 0) {
928 error_report("Cannot open %s: %s", argv[optind],
929 strerror(errno));
930 exit(EXIT_FAILURE);
931 }
932 nbd_disconnect(nbdfd);
933
934 close(nbdfd);
935
936 printf("%s disconnected\n", argv[optind]);
937
938 return 0;
939 }
940 #endif
941
942 if ((opts.device && !opts.verbose) || opts.fork_process) {
943 #ifndef WIN32
944 g_autoptr(GError) err = NULL;
945 int stderr_fd[2];
946 pid_t pid;
947
948 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) {
949 error_report("Error setting up communication pipe: %s",
950 err->message);
951 exit(EXIT_FAILURE);
952 }
953
954 /* Now daemonize, but keep a communication channel open to
955 * print errors and exit with the proper status code.
956 */
957 pid = fork();
958 if (pid < 0) {
959 error_report("Failed to fork: %s", strerror(errno));
960 exit(EXIT_FAILURE);
961 } else if (pid == 0) {
962 int saved_errno;
963
964 close(stderr_fd[0]);
965
966 /* Remember parent's stderr if we will be restoring it. */
967 if (opts.verbose /* fork_process is set */) {
968 opts.old_stderr = dup(STDERR_FILENO);
969 if (opts.old_stderr < 0) {
970 error_report("Could not dup original stderr: %s",
971 strerror(errno));
972 exit(EXIT_FAILURE);
973 }
974 }
975
976 ret = qemu_daemon(1, 0);
977 saved_errno = errno; /* dup2 will overwrite error below */
978
979 /* Temporarily redirect stderr to the parent's pipe... */
980 if (dup2(stderr_fd[1], STDERR_FILENO) < 0) {
981 char str[256];
982 snprintf(str, sizeof(str),
983 "%s: Failed to link stderr to the pipe: %s\n",
984 g_get_prgname(), strerror(errno));
985 /*
986 * We are unable to use error_report() here as we need to get
987 * stderr pointed to the parent's pipe. Write to that pipe
988 * manually.
989 */
990 ret = write(stderr_fd[1], str, strlen(str));
991 exit(EXIT_FAILURE);
992 }
993
994 if (ret < 0) {
995 error_report("Failed to daemonize: %s", strerror(saved_errno));
996 exit(EXIT_FAILURE);
997 }
998
999 /* ... close the descriptor we inherited and go on. */
1000 close(stderr_fd[1]);
1001 } else {
1002 bool errors = false;
1003 char *buf;
1004
1005 /* In the parent. Print error messages from the child until
1006 * it closes the pipe.
1007 */
1008 close(stderr_fd[1]);
1009 buf = g_malloc(1024);
1010 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
1011 errors = true;
1012 ret = qemu_write_full(STDERR_FILENO, buf, ret);
1013 if (ret < 0) {
1014 exit(EXIT_FAILURE);
1015 }
1016 }
1017 if (ret < 0) {
1018 error_report("Cannot read from daemon: %s",
1019 strerror(errno));
1020 exit(EXIT_FAILURE);
1021 }
1022
1023 /* Usually the daemon should not print any message.
1024 * Exit with zero status in that case.
1025 */
1026 exit(errors);
1027 }
1028 #else /* WIN32 */
1029 error_report("Unable to fork into background on Windows hosts");
1030 exit(EXIT_FAILURE);
1031 #endif /* WIN32 */
1032 }
1033
1034 if (opts.device != NULL && sockpath == NULL) {
1035 sockpath = g_malloc(128);
1036 snprintf(sockpath, 128, SOCKET_PATH, basename(opts.device));
1037 }
1038
1039 server = qio_net_listener_new();
1040 if (socket_activation == 0) {
1041 int backlog;
1042
1043 if (persistent || shared == 0) {
1044 backlog = SOMAXCONN;
1045 } else {
1046 backlog = MIN(shared, SOMAXCONN);
1047 }
1048 #ifdef CONFIG_SELINUX
1049 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) {
1050 error_report("Cannot set SELinux socket create context to %s: %s",
1051 selinux_label, strerror(errno));
1052 exit(EXIT_FAILURE);
1053 }
1054 #endif
1055 opts.saddr = nbd_build_socket_address(sockpath, bindto, port);
1056 if (qio_net_listener_open_sync(server, opts.saddr, backlog,
1057 &local_err) < 0) {
1058 object_unref(OBJECT(server));
1059 error_report_err(local_err);
1060 exit(EXIT_FAILURE);
1061 }
1062 #ifdef CONFIG_SELINUX
1063 if (selinux_label && setsockcreatecon_raw(NULL) == -1) {
1064 error_report("Cannot clear SELinux socket create context: %s",
1065 strerror(errno));
1066 exit(EXIT_FAILURE);
1067 }
1068 #endif
1069 } else {
1070 size_t i;
1071 /* See comment in check_socket_activation above. */
1072 for (i = 0; i < socket_activation; i++) {
1073 QIOChannelSocket *sioc;
1074 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1075 &local_err);
1076 if (sioc == NULL) {
1077 object_unref(OBJECT(server));
1078 error_reportf_err(local_err,
1079 "Failed to use socket activation: ");
1080 exit(EXIT_FAILURE);
1081 }
1082 qio_net_listener_add(server, sioc);
1083 object_unref(OBJECT(sioc));
1084 }
1085 }
1086
1087 qemu_init_main_loop(&error_fatal);
1088 bdrv_init();
1089 atexit(qemu_nbd_shutdown);
1090
1091 opts.srcpath = argv[optind];
1092 if (imageOpts) {
1093 QemuOpts *o;
1094 if (fmt) {
1095 error_report("--image-opts and -f are mutually exclusive");
1096 exit(EXIT_FAILURE);
1097 }
1098 o = qemu_opts_parse_noisily(&file_opts, opts.srcpath, true);
1099 if (!o) {
1100 qemu_opts_reset(&file_opts);
1101 exit(EXIT_FAILURE);
1102 }
1103 options = qemu_opts_to_qdict(o, NULL);
1104 qemu_opts_reset(&file_opts);
1105 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1106 } else {
1107 if (fmt) {
1108 options = qdict_new();
1109 qdict_put_str(options, "driver", fmt);
1110 }
1111 blk = blk_new_open(opts.srcpath, NULL, options, flags, &local_err);
1112 }
1113
1114 if (!blk) {
1115 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1116 argv[optind]);
1117 exit(EXIT_FAILURE);
1118 }
1119 bs = blk_bs(blk);
1120
1121 if (dev_offset) {
1122 QDict *raw_opts = qdict_new();
1123 qdict_put_str(raw_opts, "driver", "raw");
1124 qdict_put_str(raw_opts, "file", bs->node_name);
1125 qdict_put_int(raw_opts, "offset", dev_offset);
1126
1127 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1128
1129 blk_remove_bs(blk);
1130 blk_insert_bs(blk, bs, &error_fatal);
1131 bdrv_unref(bs);
1132 }
1133
1134 blk_set_enable_write_cache(blk, !writethrough);
1135
1136 if (sn_opts) {
1137 ret = bdrv_snapshot_load_tmp(bs,
1138 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1139 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1140 &local_err);
1141 } else if (sn_id_or_name) {
1142 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1143 &local_err);
1144 }
1145 if (ret < 0) {
1146 error_reportf_err(local_err, "Failed to load snapshot: ");
1147 exit(EXIT_FAILURE);
1148 }
1149
1150 bs->detect_zeroes = detect_zeroes;
1151
1152 nbd_server_is_qemu_nbd(shared);
1153
1154 export_opts = g_new(BlockExportOptions, 1);
1155 *export_opts = (BlockExportOptions) {
1156 .type = BLOCK_EXPORT_TYPE_NBD,
1157 .id = g_strdup("qemu-nbd-export"),
1158 .node_name = g_strdup(bdrv_get_node_name(bs)),
1159 .has_writethrough = true,
1160 .writethrough = writethrough,
1161 .has_writable = true,
1162 .writable = !readonly,
1163 .u.nbd = {
1164 .name = g_strdup(export_name),
1165 .description = g_strdup(export_description),
1166 .has_bitmaps = !!bitmaps,
1167 .bitmaps = bitmaps,
1168 .has_allocation_depth = alloc_depth,
1169 .allocation_depth = alloc_depth,
1170 },
1171 };
1172 blk_exp_add(export_opts, &error_fatal);
1173 qapi_free_BlockExportOptions(export_opts);
1174
1175 if (opts.device) {
1176 #if HAVE_NBD_DEVICE
1177 ret = pthread_create(&client_thread, NULL, nbd_client_thread, &opts);
1178 if (ret != 0) {
1179 error_report("Failed to create client thread: %s", strerror(ret));
1180 exit(EXIT_FAILURE);
1181 }
1182 #endif
1183 } else {
1184 /* Shut up GCC warnings. */
1185 memset(&client_thread, 0, sizeof(client_thread));
1186 }
1187
1188 nbd_update_server_watch();
1189
1190 if (pid_file_name) {
1191 qemu_write_pidfile(pid_file_name, &error_fatal);
1192 }
1193
1194 /* now when the initialization is (almost) complete, chdir("/")
1195 * to free any busy filesystems */
1196 if (chdir("/") < 0) {
1197 error_report("Could not chdir to root directory: %s",
1198 strerror(errno));
1199 exit(EXIT_FAILURE);
1200 }
1201
1202 if (opts.fork_process) {
1203 nbd_client_release_pipe(opts.old_stderr);
1204 }
1205
1206 state = RUNNING;
1207 do {
1208 main_loop_wait(false);
1209 if (state == TERMINATE) {
1210 blk_exp_close_all();
1211 state = TERMINATED;
1212 }
1213 } while (state != TERMINATED);
1214
1215 blk_unref(blk);
1216 if (sockpath) {
1217 unlink(sockpath);
1218 }
1219
1220 qemu_opts_del(sn_opts);
1221
1222 if (opts.device) {
1223 void *result;
1224 pthread_join(client_thread, &result);
1225 ret = (intptr_t)result;
1226 exit(ret);
1227 } else {
1228 exit(EXIT_SUCCESS);
1229 }
1230 }
1231