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 "qapi/error.h"
25 #include "qemu/cutils.h"
26 #include "sysemu/block-backend.h"
27 #include "block/block_int.h"
28 #include "block/nbd.h"
29 #include "qemu/main-loop.h"
30 #include "qemu/option.h"
31 #include "qemu/error-report.h"
32 #include "qemu/config-file.h"
33 #include "qemu/bswap.h"
34 #include "qemu/log.h"
35 #include "qemu/systemd.h"
36 #include "block/snapshot.h"
37 #include "qapi/qmp/qdict.h"
38 #include "qapi/qmp/qstring.h"
39 #include "qom/object_interfaces.h"
40 #include "io/channel-socket.h"
41 #include "io/net-listener.h"
42 #include "crypto/init.h"
43 #include "trace/control.h"
44 #include "qemu-version.h"
45
46 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
47 #define QEMU_NBD_OPT_CACHE 256
48 #define QEMU_NBD_OPT_AIO 257
49 #define QEMU_NBD_OPT_DISCARD 258
50 #define QEMU_NBD_OPT_DETECT_ZEROES 259
51 #define QEMU_NBD_OPT_OBJECT 260
52 #define QEMU_NBD_OPT_TLSCREDS 261
53 #define QEMU_NBD_OPT_IMAGE_OPTS 262
54 #define QEMU_NBD_OPT_FORK 263
55
56 #define MBR_SIZE 512
57
58 static NBDExport *exp;
59 static int verbose;
60 static char *srcpath;
61 static SocketAddress *saddr;
62 static int persistent = 0;
63 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
64 static int shared = 1;
65 static int nb_fds;
66 static QIONetListener *server;
67 static QCryptoTLSCreds *tlscreds;
68
usage(const char * name)69 static void usage(const char *name)
70 {
71 (printf) (
72 "Usage: %s [OPTIONS] FILE\n"
73 "QEMU Disk Network Block Device Server\n"
74 "\n"
75 " -h, --help display this help and exit\n"
76 " -V, --version output version information and exit\n"
77 "\n"
78 "Connection properties:\n"
79 " -p, --port=PORT port to listen on (default `%d')\n"
80 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
81 " -k, --socket=PATH path to the unix socket\n"
82 " (default '"SOCKET_PATH"')\n"
83 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
84 " -t, --persistent don't exit on the last connection\n"
85 " -v, --verbose display extra debugging information\n"
86 " -x, --export-name=NAME expose export by name (default is empty string)\n"
87 " -D, --description=TEXT export a human-readable description\n"
88 "\n"
89 "Exposing part of the image:\n"
90 " -o, --offset=OFFSET offset into the image\n"
91 " -P, --partition=NUM only expose partition NUM\n"
92 "\n"
93 "General purpose options:\n"
94 " --object type,id=ID,... define an object such as 'secret' for providing\n"
95 " passwords and/or encryption keys\n"
96 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
97 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
98 " specify tracing options\n"
99 " --fork fork off the server process and exit the parent\n"
100 " once the server is running\n"
101 #ifdef __linux__
102 "Kernel NBD client support:\n"
103 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
104 " -d, --disconnect disconnect the specified device\n"
105 "\n"
106 #endif
107 "\n"
108 "Block device options:\n"
109 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
110 " -r, --read-only export read-only\n"
111 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
112 " file with backing_file=FILE, redirect the write to\n"
113 " the temporary one\n"
114 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
115 " load an internal snapshot inside FILE and export it\n"
116 " as an read-only device, SNAPSHOT_PARAM format is\n"
117 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
118 " '[ID_OR_NAME]'\n"
119 " -n, --nocache disable host cache\n"
120 " --cache=MODE set cache mode (none, writeback, ...)\n"
121 " --aio=MODE set AIO mode (native or threads)\n"
122 " --discard=MODE set discard mode (ignore, unmap)\n"
123 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
124 " --image-opts treat FILE as a full set of image options\n"
125 "\n"
126 QEMU_HELP_BOTTOM "\n"
127 , name, NBD_DEFAULT_PORT, "DEVICE");
128 }
129
version(const char * name)130 static void version(const char *name)
131 {
132 printf(
133 "%s " QEMU_FULL_VERSION "\n"
134 "Written by Anthony Liguori.\n"
135 "\n"
136 QEMU_COPYRIGHT "\n"
137 "This is free software; see the source for copying conditions. There is NO\n"
138 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
139 , name);
140 }
141
142 struct partition_record
143 {
144 uint8_t bootable;
145 uint8_t start_head;
146 uint32_t start_cylinder;
147 uint8_t start_sector;
148 uint8_t system;
149 uint8_t end_head;
150 uint8_t end_cylinder;
151 uint8_t end_sector;
152 uint32_t start_sector_abs;
153 uint32_t nb_sectors_abs;
154 };
155
read_partition(uint8_t * p,struct partition_record * r)156 static void read_partition(uint8_t *p, struct partition_record *r)
157 {
158 r->bootable = p[0];
159 r->start_head = p[1];
160 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
161 r->start_sector = p[2] & 0x3f;
162 r->system = p[4];
163 r->end_head = p[5];
164 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
165 r->end_sector = p[6] & 0x3f;
166
167 r->start_sector_abs = ldl_le_p(p + 8);
168 r->nb_sectors_abs = ldl_le_p(p + 12);
169 }
170
find_partition(BlockBackend * blk,int partition,off_t * offset,off_t * size)171 static int find_partition(BlockBackend *blk, int partition,
172 off_t *offset, off_t *size)
173 {
174 struct partition_record mbr[4];
175 uint8_t data[MBR_SIZE];
176 int i;
177 int ext_partnum = 4;
178 int ret;
179
180 ret = blk_pread(blk, 0, data, sizeof(data));
181 if (ret < 0) {
182 error_report("error while reading: %s", strerror(-ret));
183 exit(EXIT_FAILURE);
184 }
185
186 if (data[510] != 0x55 || data[511] != 0xaa) {
187 return -EINVAL;
188 }
189
190 for (i = 0; i < 4; i++) {
191 read_partition(&data[446 + 16 * i], &mbr[i]);
192
193 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
194 continue;
195 }
196
197 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
198 struct partition_record ext[4];
199 uint8_t data1[MBR_SIZE];
200 int j;
201
202 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE,
203 data1, sizeof(data1));
204 if (ret < 0) {
205 error_report("error while reading: %s", strerror(-ret));
206 exit(EXIT_FAILURE);
207 }
208
209 for (j = 0; j < 4; j++) {
210 read_partition(&data1[446 + 16 * j], &ext[j]);
211 if (!ext[j].system || !ext[j].nb_sectors_abs) {
212 continue;
213 }
214
215 if ((ext_partnum + j + 1) == partition) {
216 *offset = (uint64_t)ext[j].start_sector_abs << 9;
217 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
218 return 0;
219 }
220 }
221 ext_partnum += 4;
222 } else if ((i + 1) == partition) {
223 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
224 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
225 return 0;
226 }
227 }
228
229 return -ENOENT;
230 }
231
termsig_handler(int signum)232 static void termsig_handler(int signum)
233 {
234 atomic_cmpxchg(&state, RUNNING, TERMINATE);
235 qemu_notify_event();
236 }
237
238
show_parts(void * arg)239 static void *show_parts(void *arg)
240 {
241 char *device = arg;
242 int nbd;
243
244 /* linux just needs an open() to trigger
245 * the partition table update
246 * but remember to load the module with max_part != 0 :
247 * modprobe nbd max_part=63
248 */
249 nbd = open(device, O_RDWR);
250 if (nbd >= 0) {
251 close(nbd);
252 }
253 return NULL;
254 }
255
nbd_client_thread(void * arg)256 static void *nbd_client_thread(void *arg)
257 {
258 char *device = arg;
259 NBDExportInfo info = { .request_sizes = false, };
260 QIOChannelSocket *sioc;
261 int fd;
262 int ret;
263 pthread_t show_parts_thread;
264 Error *local_error = NULL;
265
266 sioc = qio_channel_socket_new();
267 if (qio_channel_socket_connect_sync(sioc,
268 saddr,
269 &local_error) < 0) {
270 error_report_err(local_error);
271 goto out;
272 }
273
274 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL,
275 NULL, NULL, NULL, &info, &local_error);
276 if (ret < 0) {
277 if (local_error) {
278 error_report_err(local_error);
279 }
280 goto out_socket;
281 }
282
283 fd = open(device, O_RDWR);
284 if (fd < 0) {
285 /* Linux-only, we can use %m in printf. */
286 error_report("Failed to open %s: %m", device);
287 goto out_socket;
288 }
289
290 ret = nbd_init(fd, sioc, &info, &local_error);
291 if (ret < 0) {
292 error_report_err(local_error);
293 goto out_fd;
294 }
295
296 /* update partition table */
297 pthread_create(&show_parts_thread, NULL, show_parts, device);
298
299 if (verbose) {
300 fprintf(stderr, "NBD device %s is now connected to %s\n",
301 device, srcpath);
302 } else {
303 /* Close stderr so that the qemu-nbd process exits. */
304 dup2(STDOUT_FILENO, STDERR_FILENO);
305 }
306
307 ret = nbd_client(fd);
308 if (ret) {
309 goto out_fd;
310 }
311 close(fd);
312 object_unref(OBJECT(sioc));
313 kill(getpid(), SIGTERM);
314 return (void *) EXIT_SUCCESS;
315
316 out_fd:
317 close(fd);
318 out_socket:
319 object_unref(OBJECT(sioc));
320 out:
321 kill(getpid(), SIGTERM);
322 return (void *) EXIT_FAILURE;
323 }
324
nbd_can_accept(void)325 static int nbd_can_accept(void)
326 {
327 return state == RUNNING && nb_fds < shared;
328 }
329
nbd_export_closed(NBDExport * exp)330 static void nbd_export_closed(NBDExport *exp)
331 {
332 assert(state == TERMINATING);
333 state = TERMINATED;
334 }
335
336 static void nbd_update_server_watch(void);
337
nbd_client_closed(NBDClient * client,bool negotiated)338 static void nbd_client_closed(NBDClient *client, bool negotiated)
339 {
340 nb_fds--;
341 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
342 state = TERMINATE;
343 }
344 nbd_update_server_watch();
345 nbd_client_put(client);
346 }
347
nbd_accept(QIONetListener * listener,QIOChannelSocket * cioc,gpointer opaque)348 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
349 gpointer opaque)
350 {
351 if (state >= TERMINATE) {
352 return;
353 }
354
355 nb_fds++;
356 nbd_update_server_watch();
357 nbd_client_new(cioc, tlscreds, NULL, nbd_client_closed);
358 }
359
nbd_update_server_watch(void)360 static void nbd_update_server_watch(void)
361 {
362 if (nbd_can_accept()) {
363 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
364 } else {
365 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
366 }
367 }
368
369
nbd_build_socket_address(const char * sockpath,const char * bindto,const char * port)370 static SocketAddress *nbd_build_socket_address(const char *sockpath,
371 const char *bindto,
372 const char *port)
373 {
374 SocketAddress *saddr;
375
376 saddr = g_new0(SocketAddress, 1);
377 if (sockpath) {
378 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
379 saddr->u.q_unix.path = g_strdup(sockpath);
380 } else {
381 InetSocketAddress *inet;
382 saddr->type = SOCKET_ADDRESS_TYPE_INET;
383 inet = &saddr->u.inet;
384 inet->host = g_strdup(bindto);
385 if (port) {
386 inet->port = g_strdup(port);
387 } else {
388 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
389 }
390 }
391
392 return saddr;
393 }
394
395
396 static QemuOptsList file_opts = {
397 .name = "file",
398 .implied_opt_name = "file",
399 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
400 .desc = {
401 /* no elements => accept any params */
402 { /* end of list */ }
403 },
404 };
405
406 static QemuOptsList qemu_object_opts = {
407 .name = "object",
408 .implied_opt_name = "qom-type",
409 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
410 .desc = {
411 { }
412 },
413 };
414
415
416
nbd_get_tls_creds(const char * id,Error ** errp)417 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
418 {
419 Object *obj;
420 QCryptoTLSCreds *creds;
421
422 obj = object_resolve_path_component(
423 object_get_objects_root(), id);
424 if (!obj) {
425 error_setg(errp, "No TLS credentials with id '%s'",
426 id);
427 return NULL;
428 }
429 creds = (QCryptoTLSCreds *)
430 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
431 if (!creds) {
432 error_setg(errp, "Object with id '%s' is not TLS credentials",
433 id);
434 return NULL;
435 }
436
437 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
438 error_setg(errp,
439 "Expecting TLS credentials with a server endpoint");
440 return NULL;
441 }
442 object_ref(obj);
443 return creds;
444 }
445
setup_address_and_port(const char ** address,const char ** port)446 static void setup_address_and_port(const char **address, const char **port)
447 {
448 if (*address == NULL) {
449 *address = "0.0.0.0";
450 }
451
452 if (*port == NULL) {
453 *port = stringify(NBD_DEFAULT_PORT);
454 }
455 }
456
457 /*
458 * Check socket parameters compatibility when socket activation is used.
459 */
socket_activation_validate_opts(const char * device,const char * sockpath,const char * address,const char * port)460 static const char *socket_activation_validate_opts(const char *device,
461 const char *sockpath,
462 const char *address,
463 const char *port)
464 {
465 if (device != NULL) {
466 return "NBD device can't be set when using socket activation";
467 }
468
469 if (sockpath != NULL) {
470 return "Unix socket can't be set when using socket activation";
471 }
472
473 if (address != NULL) {
474 return "The interface can't be set when using socket activation";
475 }
476
477 if (port != NULL) {
478 return "TCP port number can't be set when using socket activation";
479 }
480
481 return NULL;
482 }
483
qemu_nbd_shutdown(void)484 static void qemu_nbd_shutdown(void)
485 {
486 job_cancel_sync_all();
487 bdrv_close_all();
488 }
489
main(int argc,char ** argv)490 int main(int argc, char **argv)
491 {
492 BlockBackend *blk;
493 BlockDriverState *bs;
494 off_t dev_offset = 0;
495 uint16_t nbdflags = 0;
496 bool disconnect = false;
497 const char *bindto = NULL;
498 const char *port = NULL;
499 char *sockpath = NULL;
500 char *device = NULL;
501 off_t fd_size;
502 QemuOpts *sn_opts = NULL;
503 const char *sn_id_or_name = NULL;
504 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:";
505 struct option lopt[] = {
506 { "help", no_argument, NULL, 'h' },
507 { "version", no_argument, NULL, 'V' },
508 { "bind", required_argument, NULL, 'b' },
509 { "port", required_argument, NULL, 'p' },
510 { "socket", required_argument, NULL, 'k' },
511 { "offset", required_argument, NULL, 'o' },
512 { "read-only", no_argument, NULL, 'r' },
513 { "partition", required_argument, NULL, 'P' },
514 { "connect", required_argument, NULL, 'c' },
515 { "disconnect", no_argument, NULL, 'd' },
516 { "snapshot", no_argument, NULL, 's' },
517 { "load-snapshot", required_argument, NULL, 'l' },
518 { "nocache", no_argument, NULL, 'n' },
519 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
520 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
521 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
522 { "detect-zeroes", required_argument, NULL,
523 QEMU_NBD_OPT_DETECT_ZEROES },
524 { "shared", required_argument, NULL, 'e' },
525 { "format", required_argument, NULL, 'f' },
526 { "persistent", no_argument, NULL, 't' },
527 { "verbose", no_argument, NULL, 'v' },
528 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
529 { "export-name", required_argument, NULL, 'x' },
530 { "description", required_argument, NULL, 'D' },
531 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
532 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
533 { "trace", required_argument, NULL, 'T' },
534 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
535 { NULL, 0, NULL, 0 }
536 };
537 int ch;
538 int opt_ind = 0;
539 char *end;
540 int flags = BDRV_O_RDWR;
541 int partition = -1;
542 int ret = 0;
543 bool seen_cache = false;
544 bool seen_discard = false;
545 bool seen_aio = false;
546 pthread_t client_thread;
547 const char *fmt = NULL;
548 Error *local_err = NULL;
549 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
550 QDict *options = NULL;
551 const char *export_name = ""; /* Default export name */
552 const char *export_description = NULL;
553 const char *tlscredsid = NULL;
554 bool imageOpts = false;
555 bool writethrough = true;
556 char *trace_file = NULL;
557 bool fork_process = false;
558 int old_stderr = -1;
559 unsigned socket_activation;
560
561 /* The client thread uses SIGTERM to interrupt the server. A signal
562 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
563 */
564 struct sigaction sa_sigterm;
565 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
566 sa_sigterm.sa_handler = termsig_handler;
567 sigaction(SIGTERM, &sa_sigterm, NULL);
568
569 #ifdef CONFIG_POSIX
570 signal(SIGPIPE, SIG_IGN);
571 #endif
572
573 module_call_init(MODULE_INIT_TRACE);
574 qcrypto_init(&error_fatal);
575
576 module_call_init(MODULE_INIT_QOM);
577 qemu_add_opts(&qemu_object_opts);
578 qemu_add_opts(&qemu_trace_opts);
579 qemu_init_exec_dir(argv[0]);
580
581 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
582 switch (ch) {
583 case 's':
584 flags |= BDRV_O_SNAPSHOT;
585 break;
586 case 'n':
587 optarg = (char *) "none";
588 /* fallthrough */
589 case QEMU_NBD_OPT_CACHE:
590 if (seen_cache) {
591 error_report("-n and --cache can only be specified once");
592 exit(EXIT_FAILURE);
593 }
594 seen_cache = true;
595 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
596 error_report("Invalid cache mode `%s'", optarg);
597 exit(EXIT_FAILURE);
598 }
599 break;
600 case QEMU_NBD_OPT_AIO:
601 if (seen_aio) {
602 error_report("--aio can only be specified once");
603 exit(EXIT_FAILURE);
604 }
605 seen_aio = true;
606 if (!strcmp(optarg, "native")) {
607 flags |= BDRV_O_NATIVE_AIO;
608 } else if (!strcmp(optarg, "threads")) {
609 /* this is the default */
610 } else {
611 error_report("invalid aio mode `%s'", optarg);
612 exit(EXIT_FAILURE);
613 }
614 break;
615 case QEMU_NBD_OPT_DISCARD:
616 if (seen_discard) {
617 error_report("--discard can only be specified once");
618 exit(EXIT_FAILURE);
619 }
620 seen_discard = true;
621 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
622 error_report("Invalid discard mode `%s'", optarg);
623 exit(EXIT_FAILURE);
624 }
625 break;
626 case QEMU_NBD_OPT_DETECT_ZEROES:
627 detect_zeroes =
628 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
629 optarg,
630 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
631 &local_err);
632 if (local_err) {
633 error_reportf_err(local_err,
634 "Failed to parse detect_zeroes mode: ");
635 exit(EXIT_FAILURE);
636 }
637 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
638 !(flags & BDRV_O_UNMAP)) {
639 error_report("setting detect-zeroes to unmap is not allowed "
640 "without setting discard operation to unmap");
641 exit(EXIT_FAILURE);
642 }
643 break;
644 case 'b':
645 bindto = optarg;
646 break;
647 case 'p':
648 port = optarg;
649 break;
650 case 'o':
651 dev_offset = strtoll (optarg, &end, 0);
652 if (*end) {
653 error_report("Invalid offset `%s'", optarg);
654 exit(EXIT_FAILURE);
655 }
656 if (dev_offset < 0) {
657 error_report("Offset must be positive `%s'", optarg);
658 exit(EXIT_FAILURE);
659 }
660 break;
661 case 'l':
662 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
663 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
664 optarg, false);
665 if (!sn_opts) {
666 error_report("Failed in parsing snapshot param `%s'",
667 optarg);
668 exit(EXIT_FAILURE);
669 }
670 } else {
671 sn_id_or_name = optarg;
672 }
673 /* fall through */
674 case 'r':
675 nbdflags |= NBD_FLAG_READ_ONLY;
676 flags &= ~BDRV_O_RDWR;
677 break;
678 case 'P':
679 partition = strtol(optarg, &end, 0);
680 if (*end) {
681 error_report("Invalid partition `%s'", optarg);
682 exit(EXIT_FAILURE);
683 }
684 if (partition < 1 || partition > 8) {
685 error_report("Invalid partition %d", partition);
686 exit(EXIT_FAILURE);
687 }
688 break;
689 case 'k':
690 sockpath = optarg;
691 if (sockpath[0] != '/') {
692 error_report("socket path must be absolute");
693 exit(EXIT_FAILURE);
694 }
695 break;
696 case 'd':
697 disconnect = true;
698 break;
699 case 'c':
700 device = optarg;
701 break;
702 case 'e':
703 shared = strtol(optarg, &end, 0);
704 if (*end) {
705 error_report("Invalid shared device number '%s'", optarg);
706 exit(EXIT_FAILURE);
707 }
708 if (shared < 1) {
709 error_report("Shared device number must be greater than 0");
710 exit(EXIT_FAILURE);
711 }
712 break;
713 case 'f':
714 fmt = optarg;
715 break;
716 case 't':
717 persistent = 1;
718 break;
719 case 'x':
720 export_name = optarg;
721 break;
722 case 'D':
723 export_description = optarg;
724 break;
725 case 'v':
726 verbose = 1;
727 break;
728 case 'V':
729 version(argv[0]);
730 exit(0);
731 break;
732 case 'h':
733 usage(argv[0]);
734 exit(0);
735 break;
736 case '?':
737 error_report("Try `%s --help' for more information.", argv[0]);
738 exit(EXIT_FAILURE);
739 case QEMU_NBD_OPT_OBJECT: {
740 QemuOpts *opts;
741 opts = qemu_opts_parse_noisily(&qemu_object_opts,
742 optarg, true);
743 if (!opts) {
744 exit(EXIT_FAILURE);
745 }
746 } break;
747 case QEMU_NBD_OPT_TLSCREDS:
748 tlscredsid = optarg;
749 break;
750 case QEMU_NBD_OPT_IMAGE_OPTS:
751 imageOpts = true;
752 break;
753 case 'T':
754 g_free(trace_file);
755 trace_file = trace_opt_parse(optarg);
756 break;
757 case QEMU_NBD_OPT_FORK:
758 fork_process = true;
759 break;
760 }
761 }
762
763 if ((argc - optind) != 1) {
764 error_report("Invalid number of arguments");
765 error_printf("Try `%s --help' for more information.\n", argv[0]);
766 exit(EXIT_FAILURE);
767 }
768
769 if (qemu_opts_foreach(&qemu_object_opts,
770 user_creatable_add_opts_foreach,
771 NULL, NULL)) {
772 exit(EXIT_FAILURE);
773 }
774
775 if (!trace_init_backends()) {
776 exit(1);
777 }
778 trace_init_file(trace_file);
779 qemu_set_log(LOG_TRACE);
780
781 socket_activation = check_socket_activation();
782 if (socket_activation == 0) {
783 setup_address_and_port(&bindto, &port);
784 } else {
785 /* Using socket activation - check user didn't use -p etc. */
786 const char *err_msg = socket_activation_validate_opts(device, sockpath,
787 bindto, port);
788 if (err_msg != NULL) {
789 error_report("%s", err_msg);
790 exit(EXIT_FAILURE);
791 }
792
793 /* qemu-nbd can only listen on a single socket. */
794 if (socket_activation > 1) {
795 error_report("qemu-nbd does not support socket activation with %s > 1",
796 "LISTEN_FDS");
797 exit(EXIT_FAILURE);
798 }
799 }
800
801 if (tlscredsid) {
802 if (sockpath) {
803 error_report("TLS is only supported with IPv4/IPv6");
804 exit(EXIT_FAILURE);
805 }
806 if (device) {
807 error_report("TLS is not supported with a host device");
808 exit(EXIT_FAILURE);
809 }
810 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err);
811 if (local_err) {
812 error_report("Failed to get TLS creds %s",
813 error_get_pretty(local_err));
814 exit(EXIT_FAILURE);
815 }
816 }
817
818 if (disconnect) {
819 int nbdfd = open(argv[optind], O_RDWR);
820 if (nbdfd < 0) {
821 error_report("Cannot open %s: %s", argv[optind],
822 strerror(errno));
823 exit(EXIT_FAILURE);
824 }
825 nbd_disconnect(nbdfd);
826
827 close(nbdfd);
828
829 printf("%s disconnected\n", argv[optind]);
830
831 return 0;
832 }
833
834 if ((device && !verbose) || fork_process) {
835 int stderr_fd[2];
836 pid_t pid;
837 int ret;
838
839 if (qemu_pipe(stderr_fd) < 0) {
840 error_report("Error setting up communication pipe: %s",
841 strerror(errno));
842 exit(EXIT_FAILURE);
843 }
844
845 /* Now daemonize, but keep a communication channel open to
846 * print errors and exit with the proper status code.
847 */
848 pid = fork();
849 if (pid < 0) {
850 error_report("Failed to fork: %s", strerror(errno));
851 exit(EXIT_FAILURE);
852 } else if (pid == 0) {
853 close(stderr_fd[0]);
854 ret = qemu_daemon(1, 0);
855
856 /* Temporarily redirect stderr to the parent's pipe... */
857 old_stderr = dup(STDERR_FILENO);
858 dup2(stderr_fd[1], STDERR_FILENO);
859 if (ret < 0) {
860 error_report("Failed to daemonize: %s", strerror(errno));
861 exit(EXIT_FAILURE);
862 }
863
864 /* ... close the descriptor we inherited and go on. */
865 close(stderr_fd[1]);
866 } else {
867 bool errors = false;
868 char *buf;
869
870 /* In the parent. Print error messages from the child until
871 * it closes the pipe.
872 */
873 close(stderr_fd[1]);
874 buf = g_malloc(1024);
875 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
876 errors = true;
877 ret = qemu_write_full(STDERR_FILENO, buf, ret);
878 if (ret < 0) {
879 exit(EXIT_FAILURE);
880 }
881 }
882 if (ret < 0) {
883 error_report("Cannot read from daemon: %s",
884 strerror(errno));
885 exit(EXIT_FAILURE);
886 }
887
888 /* Usually the daemon should not print any message.
889 * Exit with zero status in that case.
890 */
891 exit(errors);
892 }
893 }
894
895 if (device != NULL && sockpath == NULL) {
896 sockpath = g_malloc(128);
897 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
898 }
899
900 server = qio_net_listener_new();
901 if (socket_activation == 0) {
902 saddr = nbd_build_socket_address(sockpath, bindto, port);
903 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) {
904 object_unref(OBJECT(server));
905 error_report_err(local_err);
906 exit(EXIT_FAILURE);
907 }
908 } else {
909 size_t i;
910 /* See comment in check_socket_activation above. */
911 for (i = 0; i < socket_activation; i++) {
912 QIOChannelSocket *sioc;
913 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
914 &local_err);
915 if (sioc == NULL) {
916 object_unref(OBJECT(server));
917 error_report("Failed to use socket activation: %s",
918 error_get_pretty(local_err));
919 exit(EXIT_FAILURE);
920 }
921 qio_net_listener_add(server, sioc);
922 object_unref(OBJECT(sioc));
923 }
924 }
925
926 if (qemu_init_main_loop(&local_err)) {
927 error_report_err(local_err);
928 exit(EXIT_FAILURE);
929 }
930 bdrv_init();
931 atexit(qemu_nbd_shutdown);
932
933 srcpath = argv[optind];
934 if (imageOpts) {
935 QemuOpts *opts;
936 if (fmt) {
937 error_report("--image-opts and -f are mutually exclusive");
938 exit(EXIT_FAILURE);
939 }
940 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
941 if (!opts) {
942 qemu_opts_reset(&file_opts);
943 exit(EXIT_FAILURE);
944 }
945 options = qemu_opts_to_qdict(opts, NULL);
946 qemu_opts_reset(&file_opts);
947 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
948 } else {
949 if (fmt) {
950 options = qdict_new();
951 qdict_put_str(options, "driver", fmt);
952 }
953 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
954 }
955
956 if (!blk) {
957 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
958 argv[optind]);
959 exit(EXIT_FAILURE);
960 }
961 bs = blk_bs(blk);
962
963 blk_set_enable_write_cache(blk, !writethrough);
964
965 if (sn_opts) {
966 ret = bdrv_snapshot_load_tmp(bs,
967 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
968 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
969 &local_err);
970 } else if (sn_id_or_name) {
971 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
972 &local_err);
973 }
974 if (ret < 0) {
975 error_reportf_err(local_err, "Failed to load snapshot: ");
976 exit(EXIT_FAILURE);
977 }
978
979 bs->detect_zeroes = detect_zeroes;
980 fd_size = blk_getlength(blk);
981 if (fd_size < 0) {
982 error_report("Failed to determine the image length: %s",
983 strerror(-fd_size));
984 exit(EXIT_FAILURE);
985 }
986
987 if (dev_offset >= fd_size) {
988 error_report("Offset (%lld) has to be smaller than the image size "
989 "(%lld)",
990 (long long int)dev_offset, (long long int)fd_size);
991 exit(EXIT_FAILURE);
992 }
993 fd_size -= dev_offset;
994
995 if (partition != -1) {
996 ret = find_partition(blk, partition, &dev_offset, &fd_size);
997 if (ret < 0) {
998 error_report("Could not find partition %d: %s", partition,
999 strerror(-ret));
1000 exit(EXIT_FAILURE);
1001 }
1002 }
1003
1004 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed,
1005 writethrough, NULL, &local_err);
1006 if (!exp) {
1007 error_report_err(local_err);
1008 exit(EXIT_FAILURE);
1009 }
1010 nbd_export_set_name(exp, export_name);
1011 nbd_export_set_description(exp, export_description);
1012
1013 if (device) {
1014 int ret;
1015
1016 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1017 if (ret != 0) {
1018 error_report("Failed to create client thread: %s", strerror(ret));
1019 exit(EXIT_FAILURE);
1020 }
1021 } else {
1022 /* Shut up GCC warnings. */
1023 memset(&client_thread, 0, sizeof(client_thread));
1024 }
1025
1026 nbd_update_server_watch();
1027
1028 /* now when the initialization is (almost) complete, chdir("/")
1029 * to free any busy filesystems */
1030 if (chdir("/") < 0) {
1031 error_report("Could not chdir to root directory: %s",
1032 strerror(errno));
1033 exit(EXIT_FAILURE);
1034 }
1035
1036 if (fork_process) {
1037 dup2(old_stderr, STDERR_FILENO);
1038 close(old_stderr);
1039 }
1040
1041 state = RUNNING;
1042 do {
1043 main_loop_wait(false);
1044 if (state == TERMINATE) {
1045 state = TERMINATING;
1046 nbd_export_close(exp);
1047 nbd_export_put(exp);
1048 exp = NULL;
1049 }
1050 } while (state != TERMINATED);
1051
1052 blk_unref(blk);
1053 if (sockpath) {
1054 unlink(sockpath);
1055 }
1056
1057 qemu_opts_del(sn_opts);
1058
1059 if (device) {
1060 void *ret;
1061 pthread_join(client_thread, &ret);
1062 exit(ret != NULL);
1063 } else {
1064 exit(EXIT_SUCCESS);
1065 }
1066 }
1067