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 "system/block-backend.h"
28 #include "system/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 "qobject/qdict.h"
41 #include "qobject/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 #define QEMU_NBD_OPT_HANDSHAKE_LIMIT 268
74
75 #define MBR_SIZE 512
76
77 static int persistent = 0;
78 static enum { RUNNING, TERMINATE, TERMINATED } state;
79 static int shared = 1;
80 static int nb_fds;
81 static QIONetListener *server;
82 static QCryptoTLSCreds *tlscreds;
83 static const char *tlsauthz;
84 static int handshake_limit = NBD_DEFAULT_HANDSHAKE_MAX_SECS;
85
usage(const char * name)86 static void usage(const char *name)
87 {
88 (printf) (
89 "Usage: %s [OPTIONS] FILE\n"
90 " or: %s -L [OPTIONS]\n"
91 "QEMU Disk Network Block Device Utility\n"
92 "\n"
93 " -h, --help display this help and exit\n"
94 " -V, --version output version information and exit\n"
95 "\n"
96 "Connection properties:\n"
97 " -p, --port=PORT port to listen on (default `%d')\n"
98 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
99 " -k, --socket=PATH path to the unix socket\n"
100 " (default '"SOCKET_PATH"')\n"
101 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
102 " -t, --persistent don't exit on the last connection\n"
103 " -v, --verbose display extra debugging information\n"
104 " -x, --export-name=NAME expose export by name (default is empty string)\n"
105 " -D, --description=TEXT export a human-readable description\n"
106 " --handshake-limit=N limit client's handshake to N seconds (default 10)\n"
107 "\n"
108 "Exposing part of the image:\n"
109 " -o, --offset=OFFSET offset into the image\n"
110 " -A, --allocation-depth expose the allocation depth\n"
111 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
112 "\n"
113 "General purpose options:\n"
114 " -L, --list list exports available from another NBD server\n"
115 " --object type,id=ID,... define an object such as 'secret' for providing\n"
116 " passwords and/or encryption keys\n"
117 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
118 " --tls-authz=ID use id of an earlier --object to provide\n"
119 " authorization\n"
120 " --tls-hostname=HOSTNAME override hostname used to check x509 certificate\n"
121 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
122 " specify tracing options\n"
123 " --fork fork off the server process and exit the parent\n"
124 " once the server is running\n"
125 " --pid-file=PATH store the server's process ID in the given file\n"
126 #ifdef CONFIG_SELINUX
127 " --selinux-label=LABEL set SELinux process label on listening socket\n"
128 #endif
129 #if HAVE_NBD_DEVICE
130 "\n"
131 "Kernel NBD client support:\n"
132 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
133 " -d, --disconnect disconnect the specified device\n"
134 #endif
135 "\n"
136 "Block device options:\n"
137 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
138 " -r, --read-only export read-only\n"
139 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
140 " file with backing_file=FILE, redirect the write to\n"
141 " the temporary one\n"
142 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
143 " load an internal snapshot inside FILE and export it\n"
144 " as an read-only device, SNAPSHOT_PARAM format is\n"
145 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
146 " '[ID_OR_NAME]'\n"
147 " -n, --nocache disable host cache\n"
148 " --cache=MODE set cache mode used to access the disk image, the\n"
149 " valid options are: 'none', 'writeback' (default),\n"
150 " 'writethrough', 'directsync' and 'unsafe'\n"
151 " --aio=MODE set AIO mode (native, io_uring or threads)\n"
152 " --discard=MODE set discard mode (ignore, unmap)\n"
153 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
154 " --image-opts treat FILE as a full set of image options\n"
155 "\n"
156 QEMU_HELP_BOTTOM "\n"
157 , name, name, NBD_DEFAULT_PORT, "DEVICE");
158 }
159
version(const char * name)160 static void version(const char *name)
161 {
162 printf(
163 "%s " QEMU_FULL_VERSION "\n"
164 "Written by Anthony Liguori.\n"
165 "\n"
166 QEMU_COPYRIGHT "\n"
167 "This is free software; see the source for copying conditions. There is NO\n"
168 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
169 , name);
170 }
171
172 #ifdef CONFIG_POSIX
173 /*
174 * The client thread uses SIGTERM to interrupt the server. A signal
175 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
176 */
qemu_system_killed(int signum,pid_t pid)177 void qemu_system_killed(int signum, pid_t pid)
178 {
179 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
180 qemu_notify_event();
181 }
182 #endif /* CONFIG_POSIX */
183
qemu_nbd_client_list(SocketAddress * saddr,QCryptoTLSCreds * tls,const char * hostname)184 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
185 const char *hostname)
186 {
187 int ret = EXIT_FAILURE;
188 int rc;
189 Error *err = NULL;
190 QIOChannelSocket *sioc;
191 NBDExportInfo *list;
192 int i, j;
193
194 sioc = qio_channel_socket_new();
195 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
196 error_report_err(err);
197 goto out;
198 }
199 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
200 &err);
201 if (rc < 0) {
202 if (err) {
203 error_report_err(err);
204 }
205 goto out;
206 }
207 printf("exports available: %d\n", rc);
208 for (i = 0; i < rc; i++) {
209 printf(" export: '%s'\n", list[i].name);
210 if (list[i].description && *list[i].description) {
211 printf(" description: %s\n", list[i].description);
212 }
213 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
214 static const char *const flag_names[] = {
215 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
216 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
217 [NBD_FLAG_SEND_FUA_BIT] = "fua",
218 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
219 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
220 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
221 [NBD_FLAG_SEND_DF_BIT] = "df",
222 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
223 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
224 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
225 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
226 [NBD_FLAG_BLOCK_STAT_PAYLOAD_BIT] = "block-status-payload",
227 };
228
229 printf(" size: %" PRIu64 "\n", list[i].size);
230 printf(" flags: 0x%x (", list[i].flags);
231 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
232 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
233 printf(" %s", flag_names[bit]);
234 }
235 }
236 printf(" )\n");
237 }
238 if (list[i].min_block) {
239 printf(" min block: %u\n", list[i].min_block);
240 printf(" opt block: %u\n", list[i].opt_block);
241 printf(" max block: %u\n", list[i].max_block);
242 }
243 printf(" transaction size: %s\n",
244 list[i].mode >= NBD_MODE_EXTENDED ?
245 "64-bit" : "32-bit");
246 if (list[i].n_contexts) {
247 printf(" available meta contexts: %d\n", list[i].n_contexts);
248 for (j = 0; j < list[i].n_contexts; j++) {
249 printf(" %s\n", list[i].contexts[j]);
250 }
251 }
252 }
253 nbd_free_export_list(list, rc);
254
255 ret = EXIT_SUCCESS;
256 out:
257 object_unref(OBJECT(sioc));
258 return ret;
259 }
260
261
262 struct NbdClientOpts {
263 char *device;
264 char *srcpath;
265 SocketAddress *saddr;
266 int old_stderr;
267 bool fork_process;
268 bool verbose;
269 };
270
nbd_client_release_pipe(int old_stderr)271 static void nbd_client_release_pipe(int old_stderr)
272 {
273 /* Close stderr so that the qemu-nbd process exits. */
274 if (dup2(old_stderr, STDERR_FILENO) < 0) {
275 error_report("Could not release pipe to parent: %s",
276 strerror(errno));
277 exit(EXIT_FAILURE);
278 }
279 if (old_stderr != STDOUT_FILENO && close(old_stderr) < 0) {
280 error_report("Could not release qemu-nbd: %s", strerror(errno));
281 exit(EXIT_FAILURE);
282 }
283 }
284
285 #if HAVE_NBD_DEVICE
show_parts(void * arg)286 static void *show_parts(void *arg)
287 {
288 char *device = arg;
289 int nbd;
290
291 /* linux just needs an open() to trigger
292 * the partition table update
293 * but remember to load the module with max_part != 0 :
294 * modprobe nbd max_part=63
295 */
296 nbd = open(device, O_RDWR);
297 if (nbd >= 0) {
298 close(nbd);
299 }
300 return NULL;
301 }
302
nbd_client_thread(void * arg)303 static void *nbd_client_thread(void *arg)
304 {
305 struct NbdClientOpts *opts = arg;
306 /* TODO: Revisit this if nbd.ko ever gains support for structured reply */
307 NBDExportInfo info = { .request_sizes = false, .name = g_strdup(""),
308 .mode = NBD_MODE_SIMPLE };
309 QIOChannelSocket *sioc;
310 int fd = -1;
311 int ret = EXIT_FAILURE;
312 pthread_t show_parts_thread;
313 Error *local_error = NULL;
314
315 sioc = qio_channel_socket_new();
316 if (qio_channel_socket_connect_sync(sioc,
317 opts->saddr,
318 &local_error) < 0) {
319 error_report_err(local_error);
320 goto out;
321 }
322
323 if (nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, NULL, NULL,
324 &info, &local_error) < 0) {
325 if (local_error) {
326 error_report_err(local_error);
327 }
328 goto out;
329 }
330
331 fd = open(opts->device, O_RDWR);
332 if (fd < 0) {
333 /* Linux-only, we can use %m in printf. */
334 error_report("Failed to open %s: %m", opts->device);
335 goto out;
336 }
337
338 if (nbd_init(fd, sioc, &info, &local_error) < 0) {
339 error_report_err(local_error);
340 goto out;
341 }
342
343 /* update partition table */
344 pthread_create(&show_parts_thread, NULL, show_parts, opts->device);
345
346 if (opts->verbose && !opts->fork_process) {
347 fprintf(stderr, "NBD device %s is now connected to %s\n",
348 opts->device, opts->srcpath);
349 } else {
350 nbd_client_release_pipe(opts->old_stderr);
351 }
352
353 if (nbd_client(fd) < 0) {
354 goto out;
355 }
356
357 ret = EXIT_SUCCESS;
358
359 out:
360 if (fd >= 0) {
361 close(fd);
362 }
363 object_unref(OBJECT(sioc));
364 g_free(info.name);
365 kill(getpid(), SIGTERM);
366 return (void *) (intptr_t) ret;
367 }
368 #endif /* HAVE_NBD_DEVICE */
369
nbd_can_accept(void)370 static int nbd_can_accept(void)
371 {
372 return state == RUNNING && (shared == 0 || nb_fds < shared);
373 }
374
375 static void nbd_update_server_watch(void);
376
nbd_client_closed(NBDClient * client,bool negotiated)377 static void nbd_client_closed(NBDClient *client, bool negotiated)
378 {
379 nb_fds--;
380 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
381 state = TERMINATE;
382 }
383 nbd_update_server_watch();
384 nbd_client_put(client);
385 }
386
nbd_accept(QIONetListener * listener,QIOChannelSocket * cioc,gpointer opaque)387 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
388 gpointer opaque)
389 {
390 if (state >= TERMINATE) {
391 return;
392 }
393
394 nb_fds++;
395 nbd_update_server_watch();
396 nbd_client_new(cioc, handshake_limit,
397 tlscreds, tlsauthz, nbd_client_closed, NULL);
398 }
399
nbd_update_server_watch(void)400 static void nbd_update_server_watch(void)
401 {
402 if (nbd_can_accept()) {
403 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
404 } else {
405 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
406 }
407 }
408
409
nbd_build_socket_address(const char * sockpath,const char * bindto,const char * port)410 static SocketAddress *nbd_build_socket_address(const char *sockpath,
411 const char *bindto,
412 const char *port)
413 {
414 SocketAddress *saddr;
415
416 saddr = g_new0(SocketAddress, 1);
417 if (sockpath) {
418 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
419 saddr->u.q_unix.path = g_strdup(sockpath);
420 } else {
421 InetSocketAddress *inet;
422 saddr->type = SOCKET_ADDRESS_TYPE_INET;
423 inet = &saddr->u.inet;
424 inet->host = g_strdup(bindto);
425 if (port) {
426 inet->port = g_strdup(port);
427 } else {
428 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
429 }
430 }
431
432 return saddr;
433 }
434
435
436 static QemuOptsList file_opts = {
437 .name = "file",
438 .implied_opt_name = "file",
439 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
440 .desc = {
441 /* no elements => accept any params */
442 { /* end of list */ }
443 },
444 };
445
nbd_get_tls_creds(const char * id,bool list,Error ** errp)446 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
447 Error **errp)
448 {
449 Object *obj;
450 QCryptoTLSCreds *creds;
451
452 obj = object_resolve_path_component(
453 object_get_objects_root(), id);
454 if (!obj) {
455 error_setg(errp, "No TLS credentials with id '%s'",
456 id);
457 return NULL;
458 }
459 creds = (QCryptoTLSCreds *)
460 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
461 if (!creds) {
462 error_setg(errp, "Object with id '%s' is not TLS credentials",
463 id);
464 return NULL;
465 }
466
467 if (!qcrypto_tls_creds_check_endpoint(creds,
468 list
469 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT
470 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
471 errp)) {
472 return NULL;
473 }
474 object_ref(obj);
475 return creds;
476 }
477
setup_address_and_port(const char ** address,const char ** port)478 static void setup_address_and_port(const char **address, const char **port)
479 {
480 if (*address == NULL) {
481 *address = "0.0.0.0";
482 }
483
484 if (*port == NULL) {
485 *port = stringify(NBD_DEFAULT_PORT);
486 }
487 }
488
489 /*
490 * Check socket parameters compatibility when socket activation is used.
491 */
socket_activation_validate_opts(const char * device,const char * sockpath,const char * address,const char * port,const char * selinux,bool list)492 static const char *socket_activation_validate_opts(const char *device,
493 const char *sockpath,
494 const char *address,
495 const char *port,
496 const char *selinux,
497 bool list)
498 {
499 if (device != NULL) {
500 return "NBD device can't be set when using socket activation";
501 }
502
503 if (sockpath != NULL) {
504 return "Unix socket can't be set when using socket activation";
505 }
506
507 if (address != NULL) {
508 return "The interface can't be set when using socket activation";
509 }
510
511 if (port != NULL) {
512 return "TCP port number can't be set when using socket activation";
513 }
514
515 if (selinux != NULL) {
516 return "SELinux label can't be set when using socket activation";
517 }
518
519 if (list) {
520 return "List mode is incompatible with socket activation";
521 }
522
523 return NULL;
524 }
525
qemu_nbd_shutdown(void)526 static void qemu_nbd_shutdown(void)
527 {
528 job_cancel_sync_all();
529 blk_exp_close_all();
530 bdrv_close_all();
531 }
532
main(int argc,char ** argv)533 int main(int argc, char **argv)
534 {
535 BlockBackend *blk;
536 BlockDriverState *bs;
537 uint64_t dev_offset = 0;
538 bool readonly = false;
539 bool disconnect = false;
540 const char *bindto = NULL;
541 const char *port = NULL;
542 char *sockpath = NULL;
543 QemuOpts *sn_opts = NULL;
544 const char *sn_id_or_name = NULL;
545 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
546 struct option lopt[] = {
547 { "help", no_argument, NULL, 'h' },
548 { "version", no_argument, NULL, 'V' },
549 { "bind", required_argument, NULL, 'b' },
550 { "port", required_argument, NULL, 'p' },
551 { "socket", required_argument, NULL, 'k' },
552 { "offset", required_argument, NULL, 'o' },
553 { "read-only", no_argument, NULL, 'r' },
554 { "allocation-depth", no_argument, NULL, 'A' },
555 { "bitmap", required_argument, NULL, 'B' },
556 { "connect", required_argument, NULL, 'c' },
557 { "disconnect", no_argument, NULL, 'd' },
558 { "list", no_argument, NULL, 'L' },
559 { "snapshot", no_argument, NULL, 's' },
560 { "load-snapshot", required_argument, NULL, 'l' },
561 { "nocache", no_argument, NULL, 'n' },
562 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
563 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
564 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
565 { "detect-zeroes", required_argument, NULL,
566 QEMU_NBD_OPT_DETECT_ZEROES },
567 { "shared", required_argument, NULL, 'e' },
568 { "format", required_argument, NULL, 'f' },
569 { "persistent", no_argument, NULL, 't' },
570 { "verbose", no_argument, NULL, 'v' },
571 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
572 { "export-name", required_argument, NULL, 'x' },
573 { "description", required_argument, NULL, 'D' },
574 { "handshake-limit", required_argument, NULL,
575 QEMU_NBD_OPT_HANDSHAKE_LIMIT },
576 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
577 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME },
578 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
579 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
580 { "trace", required_argument, NULL, 'T' },
581 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
582 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
583 { "selinux-label", required_argument, NULL,
584 QEMU_NBD_OPT_SELINUX_LABEL },
585 { NULL, 0, NULL, 0 }
586 };
587 int ch;
588 int opt_ind = 0;
589 int flags = BDRV_O_RDWR;
590 int ret = 0;
591 bool seen_cache = false;
592 bool seen_discard = false;
593 bool seen_aio = false;
594 pthread_t client_thread;
595 const char *fmt = NULL;
596 Error *local_err = NULL;
597 BlockdevDetectZeroesOptions detect_zeroes =
598 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
599 QDict *options = NULL;
600 const char *export_name = NULL; /* defaults to "" later for server mode */
601 const char *export_description = NULL;
602 BlockDirtyBitmapOrStrList *bitmaps = NULL;
603 bool alloc_depth = false;
604 const char *tlscredsid = NULL;
605 const char *tlshostname = NULL;
606 bool imageOpts = false;
607 bool writethrough = false; /* Client will flush as needed. */
608 bool list = false;
609 unsigned socket_activation;
610 const char *pid_file_name = NULL;
611 const char *selinux_label = NULL;
612 BlockExportOptions *export_opts;
613 struct NbdClientOpts opts = {
614 .fork_process = false,
615 .verbose = false,
616 .device = NULL,
617 .srcpath = NULL,
618 .saddr = NULL,
619 .old_stderr = STDOUT_FILENO,
620 };
621
622 #ifdef CONFIG_POSIX
623 os_setup_early_signal_handling();
624 os_setup_signal_handling();
625 #endif
626
627 socket_init();
628 error_init(argv[0]);
629 module_call_init(MODULE_INIT_TRACE);
630 qcrypto_init(&error_fatal);
631
632 module_call_init(MODULE_INIT_QOM);
633 qemu_add_opts(&qemu_trace_opts);
634 qemu_init_exec_dir(argv[0]);
635
636 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
637 switch (ch) {
638 case 's':
639 flags |= BDRV_O_SNAPSHOT;
640 break;
641 case 'n':
642 optarg = (char *) "none";
643 /* fallthrough */
644 case QEMU_NBD_OPT_CACHE:
645 if (seen_cache) {
646 error_report("-n and --cache can only be specified once");
647 exit(EXIT_FAILURE);
648 }
649 seen_cache = true;
650 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
651 error_report("Invalid cache mode `%s'", optarg);
652 exit(EXIT_FAILURE);
653 }
654 break;
655 case QEMU_NBD_OPT_AIO:
656 if (seen_aio) {
657 error_report("--aio can only be specified once");
658 exit(EXIT_FAILURE);
659 }
660 seen_aio = true;
661 if (bdrv_parse_aio(optarg, &flags) < 0) {
662 error_report("Invalid aio mode '%s'", optarg);
663 exit(EXIT_FAILURE);
664 }
665 break;
666 case QEMU_NBD_OPT_DISCARD:
667 if (seen_discard) {
668 error_report("--discard can only be specified once");
669 exit(EXIT_FAILURE);
670 }
671 seen_discard = true;
672 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
673 error_report("Invalid discard mode `%s'", optarg);
674 exit(EXIT_FAILURE);
675 }
676 break;
677 case QEMU_NBD_OPT_DETECT_ZEROES:
678 detect_zeroes =
679 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
680 optarg,
681 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
682 &local_err);
683 if (local_err) {
684 error_reportf_err(local_err,
685 "Failed to parse detect_zeroes mode: ");
686 exit(EXIT_FAILURE);
687 }
688 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
689 !(flags & BDRV_O_UNMAP)) {
690 error_report("setting detect-zeroes to unmap is not allowed "
691 "without setting discard operation to unmap");
692 exit(EXIT_FAILURE);
693 }
694 break;
695 case 'b':
696 bindto = optarg;
697 break;
698 case 'p':
699 port = optarg;
700 break;
701 case 'o':
702 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
703 error_report("Invalid offset '%s'", optarg);
704 exit(EXIT_FAILURE);
705 }
706 break;
707 case 'l':
708 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
709 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
710 optarg, false);
711 if (!sn_opts) {
712 error_report("Failed in parsing snapshot param `%s'",
713 optarg);
714 exit(EXIT_FAILURE);
715 }
716 } else {
717 sn_id_or_name = optarg;
718 }
719 /* fall through */
720 case 'r':
721 readonly = true;
722 flags &= ~BDRV_O_RDWR;
723 break;
724 case 'A':
725 alloc_depth = true;
726 break;
727 case 'B':
728 {
729 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1);
730 *el = (BlockDirtyBitmapOrStr) {
731 .type = QTYPE_QSTRING,
732 .u.local = g_strdup(optarg),
733 };
734 QAPI_LIST_PREPEND(bitmaps, el);
735 }
736 break;
737 case 'k':
738 sockpath = optarg;
739 if (sockpath[0] != '/') {
740 error_report("socket path must be absolute");
741 exit(EXIT_FAILURE);
742 }
743 break;
744 case 'd':
745 disconnect = true;
746 break;
747 case 'c':
748 opts.device = optarg;
749 break;
750 case 'e':
751 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
752 shared < 0) {
753 error_report("Invalid shared device number '%s'", optarg);
754 exit(EXIT_FAILURE);
755 }
756 break;
757 case 'f':
758 fmt = optarg;
759 break;
760 case 't':
761 persistent = 1;
762 break;
763 case 'x':
764 export_name = optarg;
765 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
766 error_report("export name '%s' too long", export_name);
767 exit(EXIT_FAILURE);
768 }
769 break;
770 case 'D':
771 export_description = optarg;
772 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
773 error_report("export description '%s' too long",
774 export_description);
775 exit(EXIT_FAILURE);
776 }
777 break;
778 case 'v':
779 opts.verbose = true;
780 break;
781 case 'V':
782 version(argv[0]);
783 exit(0);
784 break;
785 case 'h':
786 usage(argv[0]);
787 exit(0);
788 break;
789 case '?':
790 error_report("Try `%s --help' for more information.", argv[0]);
791 exit(EXIT_FAILURE);
792 case QEMU_NBD_OPT_OBJECT:
793 user_creatable_process_cmdline(optarg);
794 break;
795 case QEMU_NBD_OPT_TLSCREDS:
796 tlscredsid = optarg;
797 break;
798 case QEMU_NBD_OPT_TLSHOSTNAME:
799 tlshostname = optarg;
800 break;
801 case QEMU_NBD_OPT_IMAGE_OPTS:
802 imageOpts = true;
803 break;
804 case 'T':
805 trace_opt_parse(optarg);
806 break;
807 case QEMU_NBD_OPT_TLSAUTHZ:
808 tlsauthz = optarg;
809 break;
810 case QEMU_NBD_OPT_FORK:
811 opts.fork_process = true;
812 break;
813 case 'L':
814 list = true;
815 break;
816 case QEMU_NBD_OPT_PID_FILE:
817 pid_file_name = optarg;
818 break;
819 case QEMU_NBD_OPT_SELINUX_LABEL:
820 selinux_label = optarg;
821 break;
822 case QEMU_NBD_OPT_HANDSHAKE_LIMIT:
823 if (qemu_strtoi(optarg, NULL, 0, &handshake_limit) < 0 ||
824 handshake_limit < 0) {
825 error_report("Invalid handshake limit '%s'", optarg);
826 exit(EXIT_FAILURE);
827 }
828 break;
829 }
830 }
831
832 if (list) {
833 if (argc != optind) {
834 error_report("List mode is incompatible with a file name");
835 exit(EXIT_FAILURE);
836 }
837 if (export_name || export_description || dev_offset ||
838 opts.device || disconnect || fmt || sn_id_or_name || bitmaps ||
839 alloc_depth || seen_aio || seen_discard || seen_cache) {
840 error_report("List mode is incompatible with per-device settings");
841 exit(EXIT_FAILURE);
842 }
843 if (opts.fork_process) {
844 error_report("List mode is incompatible with forking");
845 exit(EXIT_FAILURE);
846 }
847 } else if ((argc - optind) != 1) {
848 error_report("Invalid number of arguments");
849 error_printf("Try `%s --help' for more information.\n", argv[0]);
850 exit(EXIT_FAILURE);
851 } else if (!export_name) {
852 export_name = "";
853 }
854
855 qemu_set_log(LOG_TRACE, &error_fatal);
856
857 socket_activation = check_socket_activation();
858 if (socket_activation == 0) {
859 if (!sockpath) {
860 setup_address_and_port(&bindto, &port);
861 }
862 } else {
863 /* Using socket activation - check user didn't use -p etc. */
864 const char *err_msg = socket_activation_validate_opts(opts.device,
865 sockpath,
866 bindto, port,
867 selinux_label,
868 list);
869 if (err_msg != NULL) {
870 error_report("%s", err_msg);
871 exit(EXIT_FAILURE);
872 }
873
874 /* qemu-nbd can only listen on a single socket. */
875 if (socket_activation > 1) {
876 error_report("qemu-nbd does not support socket activation with %s > 1",
877 "LISTEN_FDS");
878 exit(EXIT_FAILURE);
879 }
880 }
881
882 if (tlscredsid) {
883 if (opts.device) {
884 error_report("TLS is not supported with a host device");
885 exit(EXIT_FAILURE);
886 }
887 if (tlsauthz && list) {
888 error_report("TLS authorization is incompatible with export list");
889 exit(EXIT_FAILURE);
890 }
891 if (tlshostname && !list) {
892 error_report("TLS hostname is only supported with export list");
893 exit(EXIT_FAILURE);
894 }
895 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
896 if (local_err) {
897 error_reportf_err(local_err, "Failed to get TLS creds: ");
898 exit(EXIT_FAILURE);
899 }
900 } else {
901 if (tlsauthz) {
902 error_report("--tls-authz is not permitted without --tls-creds");
903 exit(EXIT_FAILURE);
904 }
905 if (tlshostname) {
906 error_report("--tls-hostname is not permitted without --tls-creds");
907 exit(EXIT_FAILURE);
908 }
909 }
910
911 if (selinux_label) {
912 #ifdef CONFIG_SELINUX
913 if (sockpath == NULL && opts.device == NULL) {
914 error_report("--selinux-label is not permitted without --socket");
915 exit(EXIT_FAILURE);
916 }
917 #else
918 error_report("SELinux support not enabled in this binary");
919 exit(EXIT_FAILURE);
920 #endif
921 }
922
923 if (list) {
924 opts.saddr = nbd_build_socket_address(sockpath, bindto, port);
925 return qemu_nbd_client_list(opts.saddr, tlscreds,
926 tlshostname ? tlshostname : bindto);
927 }
928
929 #if !HAVE_NBD_DEVICE
930 if (disconnect || opts.device) {
931 error_report("Kernel /dev/nbdN support not available");
932 exit(EXIT_FAILURE);
933 }
934 #else /* HAVE_NBD_DEVICE */
935 if (disconnect) {
936 int nbdfd = open(argv[optind], O_RDWR);
937 if (nbdfd < 0) {
938 error_report("Cannot open %s: %s", argv[optind],
939 strerror(errno));
940 exit(EXIT_FAILURE);
941 }
942 nbd_disconnect(nbdfd);
943
944 close(nbdfd);
945
946 printf("%s disconnected\n", argv[optind]);
947
948 return 0;
949 }
950 #endif
951
952 if ((opts.device && !opts.verbose) || opts.fork_process) {
953 #ifndef WIN32
954 g_autoptr(GError) err = NULL;
955 int stderr_fd[2];
956 pid_t pid;
957
958 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) {
959 error_report("Error setting up communication pipe: %s",
960 err->message);
961 exit(EXIT_FAILURE);
962 }
963
964 /* Now daemonize, but keep a communication channel open to
965 * print errors and exit with the proper status code.
966 */
967 pid = fork();
968 if (pid < 0) {
969 error_report("Failed to fork: %s", strerror(errno));
970 exit(EXIT_FAILURE);
971 } else if (pid == 0) {
972 int saved_errno;
973
974 close(stderr_fd[0]);
975
976 /* Remember parent's stderr if we will be restoring it. */
977 if (opts.verbose /* fork_process is set */) {
978 opts.old_stderr = dup(STDERR_FILENO);
979 if (opts.old_stderr < 0) {
980 error_report("Could not dup original stderr: %s",
981 strerror(errno));
982 exit(EXIT_FAILURE);
983 }
984 }
985
986 ret = qemu_daemon(1, 0);
987 saved_errno = errno; /* dup2 will overwrite error below */
988
989 /* Temporarily redirect stderr to the parent's pipe... */
990 if (dup2(stderr_fd[1], STDERR_FILENO) < 0) {
991 char str[256];
992 snprintf(str, sizeof(str),
993 "%s: Failed to link stderr to the pipe: %s\n",
994 g_get_prgname(), strerror(errno));
995 /*
996 * We are unable to use error_report() here as we need to get
997 * stderr pointed to the parent's pipe. Write to that pipe
998 * manually.
999 */
1000 ret = write(stderr_fd[1], str, strlen(str));
1001 exit(EXIT_FAILURE);
1002 }
1003
1004 if (ret < 0) {
1005 error_report("Failed to daemonize: %s", strerror(saved_errno));
1006 exit(EXIT_FAILURE);
1007 }
1008
1009 /* ... close the descriptor we inherited and go on. */
1010 close(stderr_fd[1]);
1011 } else {
1012 bool errors = false;
1013 char *buf;
1014
1015 /* In the parent. Print error messages from the child until
1016 * it closes the pipe.
1017 */
1018 close(stderr_fd[1]);
1019 buf = g_malloc(1024);
1020 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
1021 errors = true;
1022 ret = qemu_write_full(STDERR_FILENO, buf, ret);
1023 if (ret < 0) {
1024 exit(EXIT_FAILURE);
1025 }
1026 }
1027 if (ret < 0) {
1028 error_report("Cannot read from daemon: %s",
1029 strerror(errno));
1030 exit(EXIT_FAILURE);
1031 }
1032
1033 /* Usually the daemon should not print any message.
1034 * Exit with zero status in that case.
1035 */
1036 exit(errors);
1037 }
1038 #else /* WIN32 */
1039 error_report("Unable to fork into background on Windows hosts");
1040 exit(EXIT_FAILURE);
1041 #endif /* WIN32 */
1042 }
1043
1044 /*
1045 * trace_init must be done after daemonization. Why? Because at
1046 * least the simple backend spins up a helper thread as well as an
1047 * atexit() handler that waits on that thread, but the helper
1048 * thread won't survive a fork, leading to deadlock in the child
1049 * if we initialized pre-fork.
1050 */
1051 if (!trace_init_backends()) {
1052 exit(1);
1053 }
1054 trace_init_file();
1055
1056 if (opts.device != NULL && sockpath == NULL) {
1057 sockpath = g_malloc(128);
1058 snprintf(sockpath, 128, SOCKET_PATH, basename(opts.device));
1059 }
1060
1061 server = qio_net_listener_new();
1062 if (socket_activation == 0) {
1063 int backlog;
1064
1065 if (persistent || shared == 0) {
1066 backlog = SOMAXCONN;
1067 } else {
1068 backlog = MIN(shared, SOMAXCONN);
1069 }
1070 #ifdef CONFIG_SELINUX
1071 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) {
1072 error_report("Cannot set SELinux socket create context to %s: %s",
1073 selinux_label, strerror(errno));
1074 exit(EXIT_FAILURE);
1075 }
1076 #endif
1077 opts.saddr = nbd_build_socket_address(sockpath, bindto, port);
1078 if (qio_net_listener_open_sync(server, opts.saddr, backlog,
1079 &local_err) < 0) {
1080 object_unref(OBJECT(server));
1081 error_report_err(local_err);
1082 exit(EXIT_FAILURE);
1083 }
1084 #ifdef CONFIG_SELINUX
1085 if (selinux_label && setsockcreatecon_raw(NULL) == -1) {
1086 error_report("Cannot clear SELinux socket create context: %s",
1087 strerror(errno));
1088 exit(EXIT_FAILURE);
1089 }
1090 #endif
1091 } else {
1092 size_t i;
1093 /* See comment in check_socket_activation above. */
1094 for (i = 0; i < socket_activation; i++) {
1095 QIOChannelSocket *sioc;
1096 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1097 &local_err);
1098 if (sioc == NULL) {
1099 object_unref(OBJECT(server));
1100 error_reportf_err(local_err,
1101 "Failed to use socket activation: ");
1102 exit(EXIT_FAILURE);
1103 }
1104 qio_net_listener_add(server, sioc);
1105 object_unref(OBJECT(sioc));
1106 }
1107 }
1108
1109 qemu_init_main_loop(&error_fatal);
1110 bdrv_init();
1111 atexit(qemu_nbd_shutdown);
1112
1113 opts.srcpath = argv[optind];
1114 if (imageOpts) {
1115 QemuOpts *o;
1116 if (fmt) {
1117 error_report("--image-opts and -f are mutually exclusive");
1118 exit(EXIT_FAILURE);
1119 }
1120 o = qemu_opts_parse_noisily(&file_opts, opts.srcpath, true);
1121 if (!o) {
1122 qemu_opts_reset(&file_opts);
1123 exit(EXIT_FAILURE);
1124 }
1125 options = qemu_opts_to_qdict(o, NULL);
1126 qemu_opts_reset(&file_opts);
1127 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1128 } else {
1129 if (fmt) {
1130 options = qdict_new();
1131 qdict_put_str(options, "driver", fmt);
1132 }
1133 blk = blk_new_open(opts.srcpath, NULL, options, flags, &local_err);
1134 }
1135
1136 if (!blk) {
1137 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1138 argv[optind]);
1139 exit(EXIT_FAILURE);
1140 }
1141 bs = blk_bs(blk);
1142
1143 if (dev_offset) {
1144 QDict *raw_opts = qdict_new();
1145 qdict_put_str(raw_opts, "driver", "raw");
1146 qdict_put_str(raw_opts, "file", bs->node_name);
1147 qdict_put_int(raw_opts, "offset", dev_offset);
1148
1149 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1150
1151 blk_remove_bs(blk);
1152 blk_insert_bs(blk, bs, &error_fatal);
1153 bdrv_unref(bs);
1154 }
1155
1156 blk_set_enable_write_cache(blk, !writethrough);
1157
1158 if (sn_opts) {
1159 ret = bdrv_snapshot_load_tmp(bs,
1160 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1161 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1162 &local_err);
1163 } else if (sn_id_or_name) {
1164 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1165 &local_err);
1166 }
1167 if (ret < 0) {
1168 error_reportf_err(local_err, "Failed to load snapshot: ");
1169 exit(EXIT_FAILURE);
1170 }
1171
1172 bs->detect_zeroes = detect_zeroes;
1173
1174 nbd_server_is_qemu_nbd(shared);
1175
1176 export_opts = g_new(BlockExportOptions, 1);
1177 *export_opts = (BlockExportOptions) {
1178 .type = BLOCK_EXPORT_TYPE_NBD,
1179 .id = g_strdup("qemu-nbd-export"),
1180 .node_name = g_strdup(bdrv_get_node_name(bs)),
1181 .has_writethrough = true,
1182 .writethrough = writethrough,
1183 .has_writable = true,
1184 .writable = !readonly,
1185 .u.nbd = {
1186 .name = g_strdup(export_name),
1187 .description = g_strdup(export_description),
1188 .has_bitmaps = !!bitmaps,
1189 .bitmaps = bitmaps,
1190 .has_allocation_depth = alloc_depth,
1191 .allocation_depth = alloc_depth,
1192 },
1193 };
1194 blk_exp_add(export_opts, &error_fatal);
1195 qapi_free_BlockExportOptions(export_opts);
1196
1197 if (opts.device) {
1198 #if HAVE_NBD_DEVICE
1199 ret = pthread_create(&client_thread, NULL, nbd_client_thread, &opts);
1200 if (ret != 0) {
1201 error_report("Failed to create client thread: %s", strerror(ret));
1202 exit(EXIT_FAILURE);
1203 }
1204 #endif
1205 } else {
1206 /* Shut up GCC warnings. */
1207 memset(&client_thread, 0, sizeof(client_thread));
1208 }
1209
1210 nbd_update_server_watch();
1211
1212 if (pid_file_name) {
1213 qemu_write_pidfile(pid_file_name, &error_fatal);
1214 }
1215
1216 /* now when the initialization is (almost) complete, chdir("/")
1217 * to free any busy filesystems */
1218 if (chdir("/") < 0) {
1219 error_report("Could not chdir to root directory: %s",
1220 strerror(errno));
1221 exit(EXIT_FAILURE);
1222 }
1223
1224 if (opts.fork_process) {
1225 nbd_client_release_pipe(opts.old_stderr);
1226 }
1227
1228 state = RUNNING;
1229 do {
1230 main_loop_wait(false);
1231 if (state == TERMINATE) {
1232 blk_exp_close_all();
1233 state = TERMINATED;
1234 }
1235 } while (state != TERMINATED);
1236
1237 blk_unref(blk);
1238 if (sockpath) {
1239 unlink(sockpath);
1240 }
1241
1242 qemu_opts_del(sn_opts);
1243
1244 if (opts.device) {
1245 void *result;
1246 pthread_join(client_thread, &result);
1247 ret = (intptr_t)result;
1248 exit(ret);
1249 } else {
1250 exit(EXIT_SUCCESS);
1251 }
1252 }
1253