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-common.h"
25 #include "qapi/error.h"
26 #include "qemu/cutils.h"
27 #include "sysemu/block-backend.h"
28 #include "block/block_int.h"
29 #include "block/nbd.h"
30 #include "qemu/main-loop.h"
31 #include "qemu/module.h"
32 #include "qemu/option.h"
33 #include "qemu/error-report.h"
34 #include "qemu/config-file.h"
35 #include "qemu/bswap.h"
36 #include "qemu/log.h"
37 #include "qemu/systemd.h"
38 #include "block/snapshot.h"
39 #include "qapi/qmp/qdict.h"
40 #include "qapi/qmp/qstring.h"
41 #include "qom/object_interfaces.h"
42 #include "io/channel-socket.h"
43 #include "io/net-listener.h"
44 #include "crypto/init.h"
45 #include "trace/control.h"
46 #include "qemu-version.h"
47
48 #ifdef __linux__
49 #define HAVE_NBD_DEVICE 1
50 #else
51 #define HAVE_NBD_DEVICE 0
52 #endif
53
54 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
55 #define QEMU_NBD_OPT_CACHE 256
56 #define QEMU_NBD_OPT_AIO 257
57 #define QEMU_NBD_OPT_DISCARD 258
58 #define QEMU_NBD_OPT_DETECT_ZEROES 259
59 #define QEMU_NBD_OPT_OBJECT 260
60 #define QEMU_NBD_OPT_TLSCREDS 261
61 #define QEMU_NBD_OPT_IMAGE_OPTS 262
62 #define QEMU_NBD_OPT_FORK 263
63 #define QEMU_NBD_OPT_TLSAUTHZ 264
64 #define QEMU_NBD_OPT_PID_FILE 265
65
66 #define MBR_SIZE 512
67
68 static NBDExport *export;
69 static int verbose;
70 static char *srcpath;
71 static SocketAddress *saddr;
72 static int persistent = 0;
73 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
74 static int shared = 1;
75 static int nb_fds;
76 static QIONetListener *server;
77 static QCryptoTLSCreds *tlscreds;
78 static const char *tlsauthz;
79
usage(const char * name)80 static void usage(const char *name)
81 {
82 (printf) (
83 "Usage: %s [OPTIONS] FILE\n"
84 " or: %s -L [OPTIONS]\n"
85 "QEMU Disk Network Block Device Utility\n"
86 "\n"
87 " -h, --help display this help and exit\n"
88 " -V, --version output version information and exit\n"
89 "\n"
90 "Connection properties:\n"
91 " -p, --port=PORT port to listen on (default `%d')\n"
92 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
93 " -k, --socket=PATH path to the unix socket\n"
94 " (default '"SOCKET_PATH"')\n"
95 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
96 " -t, --persistent don't exit on the last connection\n"
97 " -v, --verbose display extra debugging information\n"
98 " -x, --export-name=NAME expose export by name (default is empty string)\n"
99 " -D, --description=TEXT export a human-readable description\n"
100 "\n"
101 "Exposing part of the image:\n"
102 " -o, --offset=OFFSET offset into the image\n"
103 " -P, --partition=NUM only expose partition NUM\n"
104 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
105 "\n"
106 "General purpose options:\n"
107 " -L, --list list exports available from another NBD server\n"
108 " --object type,id=ID,... define an object such as 'secret' for providing\n"
109 " passwords and/or encryption keys\n"
110 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
111 " --tls-authz=ID use id of an earlier --object to provide\n"
112 " authorization\n"
113 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
114 " specify tracing options\n"
115 " --fork fork off the server process and exit the parent\n"
116 " once the server is running\n"
117 " --pid-file=PATH store the server's process ID in the given file\n"
118 #if HAVE_NBD_DEVICE
119 "\n"
120 "Kernel NBD client support:\n"
121 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
122 " -d, --disconnect disconnect the specified device\n"
123 #endif
124 "\n"
125 "Block device options:\n"
126 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
127 " -r, --read-only export read-only\n"
128 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
129 " file with backing_file=FILE, redirect the write to\n"
130 " the temporary one\n"
131 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
132 " load an internal snapshot inside FILE and export it\n"
133 " as an read-only device, SNAPSHOT_PARAM format is\n"
134 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
135 " '[ID_OR_NAME]'\n"
136 " -n, --nocache disable host cache\n"
137 " --cache=MODE set cache mode (none, writeback, ...)\n"
138 " --aio=MODE set AIO mode (native or threads)\n"
139 " --discard=MODE set discard mode (ignore, unmap)\n"
140 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
141 " --image-opts treat FILE as a full set of image options\n"
142 "\n"
143 QEMU_HELP_BOTTOM "\n"
144 , name, name, NBD_DEFAULT_PORT, "DEVICE");
145 }
146
version(const char * name)147 static void version(const char *name)
148 {
149 printf(
150 "%s " QEMU_FULL_VERSION "\n"
151 "Written by Anthony Liguori.\n"
152 "\n"
153 QEMU_COPYRIGHT "\n"
154 "This is free software; see the source for copying conditions. There is NO\n"
155 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
156 , name);
157 }
158
159 struct partition_record
160 {
161 uint8_t bootable;
162 uint8_t start_head;
163 uint32_t start_cylinder;
164 uint8_t start_sector;
165 uint8_t system;
166 uint8_t end_head;
167 uint8_t end_cylinder;
168 uint8_t end_sector;
169 uint32_t start_sector_abs;
170 uint32_t nb_sectors_abs;
171 };
172
read_partition(uint8_t * p,struct partition_record * r)173 static void read_partition(uint8_t *p, struct partition_record *r)
174 {
175 r->bootable = p[0];
176 r->start_head = p[1];
177 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
178 r->start_sector = p[2] & 0x3f;
179 r->system = p[4];
180 r->end_head = p[5];
181 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
182 r->end_sector = p[6] & 0x3f;
183
184 r->start_sector_abs = ldl_le_p(p + 8);
185 r->nb_sectors_abs = ldl_le_p(p + 12);
186 }
187
find_partition(BlockBackend * blk,int partition,uint64_t * offset,uint64_t * size)188 static int find_partition(BlockBackend *blk, int partition,
189 uint64_t *offset, uint64_t *size)
190 {
191 struct partition_record mbr[4];
192 uint8_t data[MBR_SIZE];
193 int i;
194 int ext_partnum = 4;
195 int ret;
196
197 ret = blk_pread(blk, 0, data, sizeof(data));
198 if (ret < 0) {
199 error_report("error while reading: %s", strerror(-ret));
200 exit(EXIT_FAILURE);
201 }
202
203 if (data[510] != 0x55 || data[511] != 0xaa) {
204 return -EINVAL;
205 }
206
207 for (i = 0; i < 4; i++) {
208 read_partition(&data[446 + 16 * i], &mbr[i]);
209
210 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
211 continue;
212 }
213
214 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
215 struct partition_record ext[4];
216 uint8_t data1[MBR_SIZE];
217 int j;
218
219 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE,
220 data1, sizeof(data1));
221 if (ret < 0) {
222 error_report("error while reading: %s", strerror(-ret));
223 exit(EXIT_FAILURE);
224 }
225
226 for (j = 0; j < 4; j++) {
227 read_partition(&data1[446 + 16 * j], &ext[j]);
228 if (!ext[j].system || !ext[j].nb_sectors_abs) {
229 continue;
230 }
231
232 if ((ext_partnum + j + 1) == partition) {
233 *offset = (uint64_t)ext[j].start_sector_abs << 9;
234 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
235 return 0;
236 }
237 }
238 ext_partnum += 4;
239 } else if ((i + 1) == partition) {
240 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
241 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
242 return 0;
243 }
244 }
245
246 return -ENOENT;
247 }
248
termsig_handler(int signum)249 static void termsig_handler(int signum)
250 {
251 atomic_cmpxchg(&state, RUNNING, TERMINATE);
252 qemu_notify_event();
253 }
254
255
qemu_nbd_client_list(SocketAddress * saddr,QCryptoTLSCreds * tls,const char * hostname)256 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
257 const char *hostname)
258 {
259 int ret = EXIT_FAILURE;
260 int rc;
261 Error *err = NULL;
262 QIOChannelSocket *sioc;
263 NBDExportInfo *list;
264 int i, j;
265
266 sioc = qio_channel_socket_new();
267 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
268 error_report_err(err);
269 return EXIT_FAILURE;
270 }
271 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
272 &err);
273 if (rc < 0) {
274 if (err) {
275 error_report_err(err);
276 }
277 goto out;
278 }
279 printf("exports available: %d\n", rc);
280 for (i = 0; i < rc; i++) {
281 printf(" export: '%s'\n", list[i].name);
282 if (list[i].description && *list[i].description) {
283 printf(" description: %s\n", list[i].description);
284 }
285 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
286 static const char *const flag_names[] = {
287 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
288 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
289 [NBD_FLAG_SEND_FUA_BIT] = "fua",
290 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
291 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
292 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
293 [NBD_FLAG_SEND_DF_BIT] = "df",
294 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
295 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
296 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
297 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
298 };
299
300 printf(" size: %" PRIu64 "\n", list[i].size);
301 printf(" flags: 0x%x (", list[i].flags);
302 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
303 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
304 printf(" %s", flag_names[bit]);
305 }
306 }
307 printf(" )\n");
308 }
309 if (list[i].min_block) {
310 printf(" min block: %u\n", list[i].min_block);
311 printf(" opt block: %u\n", list[i].opt_block);
312 printf(" max block: %u\n", list[i].max_block);
313 }
314 if (list[i].n_contexts) {
315 printf(" available meta contexts: %d\n", list[i].n_contexts);
316 for (j = 0; j < list[i].n_contexts; j++) {
317 printf(" %s\n", list[i].contexts[j]);
318 }
319 }
320 }
321 nbd_free_export_list(list, rc);
322
323 ret = EXIT_SUCCESS;
324 out:
325 object_unref(OBJECT(sioc));
326 return ret;
327 }
328
329
330 #if HAVE_NBD_DEVICE
show_parts(void * arg)331 static void *show_parts(void *arg)
332 {
333 char *device = arg;
334 int nbd;
335
336 /* linux just needs an open() to trigger
337 * the partition table update
338 * but remember to load the module with max_part != 0 :
339 * modprobe nbd max_part=63
340 */
341 nbd = open(device, O_RDWR);
342 if (nbd >= 0) {
343 close(nbd);
344 }
345 return NULL;
346 }
347
nbd_client_thread(void * arg)348 static void *nbd_client_thread(void *arg)
349 {
350 char *device = arg;
351 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
352 QIOChannelSocket *sioc;
353 int fd;
354 int ret;
355 pthread_t show_parts_thread;
356 Error *local_error = NULL;
357
358 sioc = qio_channel_socket_new();
359 if (qio_channel_socket_connect_sync(sioc,
360 saddr,
361 &local_error) < 0) {
362 error_report_err(local_error);
363 goto out;
364 }
365
366 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
367 NULL, NULL, NULL, &info, &local_error);
368 if (ret < 0) {
369 if (local_error) {
370 error_report_err(local_error);
371 }
372 goto out_socket;
373 }
374
375 fd = open(device, O_RDWR);
376 if (fd < 0) {
377 /* Linux-only, we can use %m in printf. */
378 error_report("Failed to open %s: %m", device);
379 goto out_socket;
380 }
381
382 ret = nbd_init(fd, sioc, &info, &local_error);
383 if (ret < 0) {
384 error_report_err(local_error);
385 goto out_fd;
386 }
387
388 /* update partition table */
389 pthread_create(&show_parts_thread, NULL, show_parts, device);
390
391 if (verbose) {
392 fprintf(stderr, "NBD device %s is now connected to %s\n",
393 device, srcpath);
394 } else {
395 /* Close stderr so that the qemu-nbd process exits. */
396 dup2(STDOUT_FILENO, STDERR_FILENO);
397 }
398
399 ret = nbd_client(fd);
400 if (ret) {
401 goto out_fd;
402 }
403 close(fd);
404 object_unref(OBJECT(sioc));
405 g_free(info.name);
406 kill(getpid(), SIGTERM);
407 return (void *) EXIT_SUCCESS;
408
409 out_fd:
410 close(fd);
411 out_socket:
412 object_unref(OBJECT(sioc));
413 out:
414 g_free(info.name);
415 kill(getpid(), SIGTERM);
416 return (void *) EXIT_FAILURE;
417 }
418 #endif /* HAVE_NBD_DEVICE */
419
nbd_can_accept(void)420 static int nbd_can_accept(void)
421 {
422 return state == RUNNING && nb_fds < shared;
423 }
424
nbd_export_closed(NBDExport * export)425 static void nbd_export_closed(NBDExport *export)
426 {
427 assert(state == TERMINATING);
428 state = TERMINATED;
429 }
430
431 static void nbd_update_server_watch(void);
432
nbd_client_closed(NBDClient * client,bool negotiated)433 static void nbd_client_closed(NBDClient *client, bool negotiated)
434 {
435 nb_fds--;
436 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
437 state = TERMINATE;
438 }
439 nbd_update_server_watch();
440 nbd_client_put(client);
441 }
442
nbd_accept(QIONetListener * listener,QIOChannelSocket * cioc,gpointer opaque)443 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
444 gpointer opaque)
445 {
446 if (state >= TERMINATE) {
447 return;
448 }
449
450 nb_fds++;
451 nbd_update_server_watch();
452 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
453 }
454
nbd_update_server_watch(void)455 static void nbd_update_server_watch(void)
456 {
457 if (nbd_can_accept()) {
458 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
459 } else {
460 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
461 }
462 }
463
464
nbd_build_socket_address(const char * sockpath,const char * bindto,const char * port)465 static SocketAddress *nbd_build_socket_address(const char *sockpath,
466 const char *bindto,
467 const char *port)
468 {
469 SocketAddress *saddr;
470
471 saddr = g_new0(SocketAddress, 1);
472 if (sockpath) {
473 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
474 saddr->u.q_unix.path = g_strdup(sockpath);
475 } else {
476 InetSocketAddress *inet;
477 saddr->type = SOCKET_ADDRESS_TYPE_INET;
478 inet = &saddr->u.inet;
479 inet->host = g_strdup(bindto);
480 if (port) {
481 inet->port = g_strdup(port);
482 } else {
483 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
484 }
485 }
486
487 return saddr;
488 }
489
490
491 static QemuOptsList file_opts = {
492 .name = "file",
493 .implied_opt_name = "file",
494 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
495 .desc = {
496 /* no elements => accept any params */
497 { /* end of list */ }
498 },
499 };
500
501 static QemuOptsList qemu_object_opts = {
502 .name = "object",
503 .implied_opt_name = "qom-type",
504 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
505 .desc = {
506 { }
507 },
508 };
509
qemu_nbd_object_print_help(const char * type,QemuOpts * opts)510 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts)
511 {
512 if (user_creatable_print_help(type, opts)) {
513 exit(0);
514 }
515 return true;
516 }
517
518
nbd_get_tls_creds(const char * id,bool list,Error ** errp)519 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
520 Error **errp)
521 {
522 Object *obj;
523 QCryptoTLSCreds *creds;
524
525 obj = object_resolve_path_component(
526 object_get_objects_root(), id);
527 if (!obj) {
528 error_setg(errp, "No TLS credentials with id '%s'",
529 id);
530 return NULL;
531 }
532 creds = (QCryptoTLSCreds *)
533 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
534 if (!creds) {
535 error_setg(errp, "Object with id '%s' is not TLS credentials",
536 id);
537 return NULL;
538 }
539
540 if (list) {
541 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
542 error_setg(errp,
543 "Expecting TLS credentials with a client endpoint");
544 return NULL;
545 }
546 } else {
547 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
548 error_setg(errp,
549 "Expecting TLS credentials with a server endpoint");
550 return NULL;
551 }
552 }
553 object_ref(obj);
554 return creds;
555 }
556
setup_address_and_port(const char ** address,const char ** port)557 static void setup_address_and_port(const char **address, const char **port)
558 {
559 if (*address == NULL) {
560 *address = "0.0.0.0";
561 }
562
563 if (*port == NULL) {
564 *port = stringify(NBD_DEFAULT_PORT);
565 }
566 }
567
568 /*
569 * Check socket parameters compatibility when socket activation is used.
570 */
socket_activation_validate_opts(const char * device,const char * sockpath,const char * address,const char * port,bool list)571 static const char *socket_activation_validate_opts(const char *device,
572 const char *sockpath,
573 const char *address,
574 const char *port,
575 bool list)
576 {
577 if (device != NULL) {
578 return "NBD device can't be set when using socket activation";
579 }
580
581 if (sockpath != NULL) {
582 return "Unix socket can't be set when using socket activation";
583 }
584
585 if (address != NULL) {
586 return "The interface can't be set when using socket activation";
587 }
588
589 if (port != NULL) {
590 return "TCP port number can't be set when using socket activation";
591 }
592
593 if (list) {
594 return "List mode is incompatible with socket activation";
595 }
596
597 return NULL;
598 }
599
qemu_nbd_shutdown(void)600 static void qemu_nbd_shutdown(void)
601 {
602 job_cancel_sync_all();
603 bdrv_close_all();
604 }
605
main(int argc,char ** argv)606 int main(int argc, char **argv)
607 {
608 BlockBackend *blk;
609 BlockDriverState *bs;
610 uint64_t dev_offset = 0;
611 bool readonly = false;
612 bool disconnect = false;
613 const char *bindto = NULL;
614 const char *port = NULL;
615 char *sockpath = NULL;
616 char *device = NULL;
617 int64_t fd_size;
618 QemuOpts *sn_opts = NULL;
619 const char *sn_id_or_name = NULL;
620 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:L";
621 struct option lopt[] = {
622 { "help", no_argument, NULL, 'h' },
623 { "version", no_argument, NULL, 'V' },
624 { "bind", required_argument, NULL, 'b' },
625 { "port", required_argument, NULL, 'p' },
626 { "socket", required_argument, NULL, 'k' },
627 { "offset", required_argument, NULL, 'o' },
628 { "read-only", no_argument, NULL, 'r' },
629 { "partition", required_argument, NULL, 'P' },
630 { "bitmap", required_argument, NULL, 'B' },
631 { "connect", required_argument, NULL, 'c' },
632 { "disconnect", no_argument, NULL, 'd' },
633 { "list", no_argument, NULL, 'L' },
634 { "snapshot", no_argument, NULL, 's' },
635 { "load-snapshot", required_argument, NULL, 'l' },
636 { "nocache", no_argument, NULL, 'n' },
637 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
638 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
639 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
640 { "detect-zeroes", required_argument, NULL,
641 QEMU_NBD_OPT_DETECT_ZEROES },
642 { "shared", required_argument, NULL, 'e' },
643 { "format", required_argument, NULL, 'f' },
644 { "persistent", no_argument, NULL, 't' },
645 { "verbose", no_argument, NULL, 'v' },
646 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
647 { "export-name", required_argument, NULL, 'x' },
648 { "description", required_argument, NULL, 'D' },
649 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
650 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
651 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
652 { "trace", required_argument, NULL, 'T' },
653 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
654 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
655 { NULL, 0, NULL, 0 }
656 };
657 int ch;
658 int opt_ind = 0;
659 int flags = BDRV_O_RDWR;
660 int partition = 0;
661 int ret = 0;
662 bool seen_cache = false;
663 bool seen_discard = false;
664 bool seen_aio = false;
665 pthread_t client_thread;
666 const char *fmt = NULL;
667 Error *local_err = NULL;
668 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
669 QDict *options = NULL;
670 const char *export_name = NULL; /* defaults to "" later for server mode */
671 const char *export_description = NULL;
672 const char *bitmap = NULL;
673 const char *tlscredsid = NULL;
674 bool imageOpts = false;
675 bool writethrough = true;
676 char *trace_file = NULL;
677 bool fork_process = false;
678 bool list = false;
679 int old_stderr = -1;
680 unsigned socket_activation;
681 const char *pid_file_name = NULL;
682
683 /* The client thread uses SIGTERM to interrupt the server. A signal
684 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
685 */
686 struct sigaction sa_sigterm;
687 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
688 sa_sigterm.sa_handler = termsig_handler;
689 sigaction(SIGTERM, &sa_sigterm, NULL);
690
691 #ifdef CONFIG_POSIX
692 signal(SIGPIPE, SIG_IGN);
693 #endif
694
695 error_init(argv[0]);
696 module_call_init(MODULE_INIT_TRACE);
697 qcrypto_init(&error_fatal);
698
699 module_call_init(MODULE_INIT_QOM);
700 qemu_add_opts(&qemu_object_opts);
701 qemu_add_opts(&qemu_trace_opts);
702 qemu_init_exec_dir(argv[0]);
703
704 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
705 switch (ch) {
706 case 's':
707 flags |= BDRV_O_SNAPSHOT;
708 break;
709 case 'n':
710 optarg = (char *) "none";
711 /* fallthrough */
712 case QEMU_NBD_OPT_CACHE:
713 if (seen_cache) {
714 error_report("-n and --cache can only be specified once");
715 exit(EXIT_FAILURE);
716 }
717 seen_cache = true;
718 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
719 error_report("Invalid cache mode `%s'", optarg);
720 exit(EXIT_FAILURE);
721 }
722 break;
723 case QEMU_NBD_OPT_AIO:
724 if (seen_aio) {
725 error_report("--aio can only be specified once");
726 exit(EXIT_FAILURE);
727 }
728 seen_aio = true;
729 if (!strcmp(optarg, "native")) {
730 flags |= BDRV_O_NATIVE_AIO;
731 } else if (!strcmp(optarg, "threads")) {
732 /* this is the default */
733 } else {
734 error_report("invalid aio mode `%s'", optarg);
735 exit(EXIT_FAILURE);
736 }
737 break;
738 case QEMU_NBD_OPT_DISCARD:
739 if (seen_discard) {
740 error_report("--discard can only be specified once");
741 exit(EXIT_FAILURE);
742 }
743 seen_discard = true;
744 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
745 error_report("Invalid discard mode `%s'", optarg);
746 exit(EXIT_FAILURE);
747 }
748 break;
749 case QEMU_NBD_OPT_DETECT_ZEROES:
750 detect_zeroes =
751 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
752 optarg,
753 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
754 &local_err);
755 if (local_err) {
756 error_reportf_err(local_err,
757 "Failed to parse detect_zeroes mode: ");
758 exit(EXIT_FAILURE);
759 }
760 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
761 !(flags & BDRV_O_UNMAP)) {
762 error_report("setting detect-zeroes to unmap is not allowed "
763 "without setting discard operation to unmap");
764 exit(EXIT_FAILURE);
765 }
766 break;
767 case 'b':
768 bindto = optarg;
769 break;
770 case 'p':
771 port = optarg;
772 break;
773 case 'o':
774 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
775 error_report("Invalid offset '%s'", optarg);
776 exit(EXIT_FAILURE);
777 }
778 break;
779 case 'l':
780 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
781 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
782 optarg, false);
783 if (!sn_opts) {
784 error_report("Failed in parsing snapshot param `%s'",
785 optarg);
786 exit(EXIT_FAILURE);
787 }
788 } else {
789 sn_id_or_name = optarg;
790 }
791 /* fall through */
792 case 'r':
793 readonly = true;
794 flags &= ~BDRV_O_RDWR;
795 break;
796 case 'P':
797 warn_report("The '-P' option is deprecated; use --image-opts with "
798 "a raw device wrapper for subset exports instead");
799 if (qemu_strtoi(optarg, NULL, 0, &partition) < 0 ||
800 partition < 1 || partition > 8) {
801 error_report("Invalid partition '%s'", optarg);
802 exit(EXIT_FAILURE);
803 }
804 break;
805 case 'B':
806 bitmap = optarg;
807 break;
808 case 'k':
809 sockpath = optarg;
810 if (sockpath[0] != '/') {
811 error_report("socket path must be absolute");
812 exit(EXIT_FAILURE);
813 }
814 break;
815 case 'd':
816 disconnect = true;
817 break;
818 case 'c':
819 device = optarg;
820 break;
821 case 'e':
822 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
823 shared < 1) {
824 error_report("Invalid shared device number '%s'", optarg);
825 exit(EXIT_FAILURE);
826 }
827 break;
828 case 'f':
829 fmt = optarg;
830 break;
831 case 't':
832 persistent = 1;
833 break;
834 case 'x':
835 export_name = optarg;
836 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
837 error_report("export name '%s' too long", export_name);
838 exit(EXIT_FAILURE);
839 }
840 break;
841 case 'D':
842 export_description = optarg;
843 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
844 error_report("export description '%s' too long",
845 export_description);
846 exit(EXIT_FAILURE);
847 }
848 break;
849 case 'v':
850 verbose = 1;
851 break;
852 case 'V':
853 version(argv[0]);
854 exit(0);
855 break;
856 case 'h':
857 usage(argv[0]);
858 exit(0);
859 break;
860 case '?':
861 error_report("Try `%s --help' for more information.", argv[0]);
862 exit(EXIT_FAILURE);
863 case QEMU_NBD_OPT_OBJECT: {
864 QemuOpts *opts;
865 opts = qemu_opts_parse_noisily(&qemu_object_opts,
866 optarg, true);
867 if (!opts) {
868 exit(EXIT_FAILURE);
869 }
870 } break;
871 case QEMU_NBD_OPT_TLSCREDS:
872 tlscredsid = optarg;
873 break;
874 case QEMU_NBD_OPT_IMAGE_OPTS:
875 imageOpts = true;
876 break;
877 case 'T':
878 g_free(trace_file);
879 trace_file = trace_opt_parse(optarg);
880 break;
881 case QEMU_NBD_OPT_TLSAUTHZ:
882 tlsauthz = optarg;
883 break;
884 case QEMU_NBD_OPT_FORK:
885 fork_process = true;
886 break;
887 case 'L':
888 list = true;
889 break;
890 case QEMU_NBD_OPT_PID_FILE:
891 pid_file_name = optarg;
892 break;
893 }
894 }
895
896 if (list) {
897 if (argc != optind) {
898 error_report("List mode is incompatible with a file name");
899 exit(EXIT_FAILURE);
900 }
901 if (export_name || export_description || dev_offset || partition ||
902 device || disconnect || fmt || sn_id_or_name || bitmap ||
903 seen_aio || seen_discard || seen_cache) {
904 error_report("List mode is incompatible with per-device settings");
905 exit(EXIT_FAILURE);
906 }
907 if (fork_process) {
908 error_report("List mode is incompatible with forking");
909 exit(EXIT_FAILURE);
910 }
911 } else if ((argc - optind) != 1) {
912 error_report("Invalid number of arguments");
913 error_printf("Try `%s --help' for more information.\n", argv[0]);
914 exit(EXIT_FAILURE);
915 } else if (!export_name) {
916 export_name = "";
917 }
918
919 qemu_opts_foreach(&qemu_object_opts,
920 user_creatable_add_opts_foreach,
921 qemu_nbd_object_print_help, &error_fatal);
922
923 if (!trace_init_backends()) {
924 exit(1);
925 }
926 trace_init_file(trace_file);
927 qemu_set_log(LOG_TRACE);
928
929 socket_activation = check_socket_activation();
930 if (socket_activation == 0) {
931 setup_address_and_port(&bindto, &port);
932 } else {
933 /* Using socket activation - check user didn't use -p etc. */
934 const char *err_msg = socket_activation_validate_opts(device, sockpath,
935 bindto, port,
936 list);
937 if (err_msg != NULL) {
938 error_report("%s", err_msg);
939 exit(EXIT_FAILURE);
940 }
941
942 /* qemu-nbd can only listen on a single socket. */
943 if (socket_activation > 1) {
944 error_report("qemu-nbd does not support socket activation with %s > 1",
945 "LISTEN_FDS");
946 exit(EXIT_FAILURE);
947 }
948 }
949
950 if (tlscredsid) {
951 if (sockpath) {
952 error_report("TLS is only supported with IPv4/IPv6");
953 exit(EXIT_FAILURE);
954 }
955 if (device) {
956 error_report("TLS is not supported with a host device");
957 exit(EXIT_FAILURE);
958 }
959 if (tlsauthz && list) {
960 error_report("TLS authorization is incompatible with export list");
961 exit(EXIT_FAILURE);
962 }
963 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
964 if (local_err) {
965 error_report("Failed to get TLS creds %s",
966 error_get_pretty(local_err));
967 exit(EXIT_FAILURE);
968 }
969 } else {
970 if (tlsauthz) {
971 error_report("--tls-authz is not permitted without --tls-creds");
972 exit(EXIT_FAILURE);
973 }
974 }
975
976 if (list) {
977 saddr = nbd_build_socket_address(sockpath, bindto, port);
978 return qemu_nbd_client_list(saddr, tlscreds, bindto);
979 }
980
981 #if !HAVE_NBD_DEVICE
982 if (disconnect || device) {
983 error_report("Kernel /dev/nbdN support not available");
984 exit(EXIT_FAILURE);
985 }
986 #else /* HAVE_NBD_DEVICE */
987 if (disconnect) {
988 int nbdfd = open(argv[optind], O_RDWR);
989 if (nbdfd < 0) {
990 error_report("Cannot open %s: %s", argv[optind],
991 strerror(errno));
992 exit(EXIT_FAILURE);
993 }
994 nbd_disconnect(nbdfd);
995
996 close(nbdfd);
997
998 printf("%s disconnected\n", argv[optind]);
999
1000 return 0;
1001 }
1002 #endif
1003
1004 if ((device && !verbose) || fork_process) {
1005 int stderr_fd[2];
1006 pid_t pid;
1007 int ret;
1008
1009 if (qemu_pipe(stderr_fd) < 0) {
1010 error_report("Error setting up communication pipe: %s",
1011 strerror(errno));
1012 exit(EXIT_FAILURE);
1013 }
1014
1015 /* Now daemonize, but keep a communication channel open to
1016 * print errors and exit with the proper status code.
1017 */
1018 pid = fork();
1019 if (pid < 0) {
1020 error_report("Failed to fork: %s", strerror(errno));
1021 exit(EXIT_FAILURE);
1022 } else if (pid == 0) {
1023 close(stderr_fd[0]);
1024
1025 /* Remember parent's stderr if we will be restoring it. */
1026 if (fork_process) {
1027 old_stderr = dup(STDERR_FILENO);
1028 }
1029
1030 ret = qemu_daemon(1, 0);
1031
1032 /* Temporarily redirect stderr to the parent's pipe... */
1033 dup2(stderr_fd[1], STDERR_FILENO);
1034 if (ret < 0) {
1035 error_report("Failed to daemonize: %s", strerror(errno));
1036 exit(EXIT_FAILURE);
1037 }
1038
1039 /* ... close the descriptor we inherited and go on. */
1040 close(stderr_fd[1]);
1041 } else {
1042 bool errors = false;
1043 char *buf;
1044
1045 /* In the parent. Print error messages from the child until
1046 * it closes the pipe.
1047 */
1048 close(stderr_fd[1]);
1049 buf = g_malloc(1024);
1050 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
1051 errors = true;
1052 ret = qemu_write_full(STDERR_FILENO, buf, ret);
1053 if (ret < 0) {
1054 exit(EXIT_FAILURE);
1055 }
1056 }
1057 if (ret < 0) {
1058 error_report("Cannot read from daemon: %s",
1059 strerror(errno));
1060 exit(EXIT_FAILURE);
1061 }
1062
1063 /* Usually the daemon should not print any message.
1064 * Exit with zero status in that case.
1065 */
1066 exit(errors);
1067 }
1068 }
1069
1070 if (device != NULL && sockpath == NULL) {
1071 sockpath = g_malloc(128);
1072 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
1073 }
1074
1075 server = qio_net_listener_new();
1076 if (socket_activation == 0) {
1077 saddr = nbd_build_socket_address(sockpath, bindto, port);
1078 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) {
1079 object_unref(OBJECT(server));
1080 error_report_err(local_err);
1081 exit(EXIT_FAILURE);
1082 }
1083 } else {
1084 size_t i;
1085 /* See comment in check_socket_activation above. */
1086 for (i = 0; i < socket_activation; i++) {
1087 QIOChannelSocket *sioc;
1088 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1089 &local_err);
1090 if (sioc == NULL) {
1091 object_unref(OBJECT(server));
1092 error_report("Failed to use socket activation: %s",
1093 error_get_pretty(local_err));
1094 exit(EXIT_FAILURE);
1095 }
1096 qio_net_listener_add(server, sioc);
1097 object_unref(OBJECT(sioc));
1098 }
1099 }
1100
1101 if (qemu_init_main_loop(&local_err)) {
1102 error_report_err(local_err);
1103 exit(EXIT_FAILURE);
1104 }
1105 bdrv_init();
1106 atexit(qemu_nbd_shutdown);
1107
1108 srcpath = argv[optind];
1109 if (imageOpts) {
1110 QemuOpts *opts;
1111 if (fmt) {
1112 error_report("--image-opts and -f are mutually exclusive");
1113 exit(EXIT_FAILURE);
1114 }
1115 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1116 if (!opts) {
1117 qemu_opts_reset(&file_opts);
1118 exit(EXIT_FAILURE);
1119 }
1120 options = qemu_opts_to_qdict(opts, NULL);
1121 qemu_opts_reset(&file_opts);
1122 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1123 } else {
1124 if (fmt) {
1125 options = qdict_new();
1126 qdict_put_str(options, "driver", fmt);
1127 }
1128 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1129 }
1130
1131 if (!blk) {
1132 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1133 argv[optind]);
1134 exit(EXIT_FAILURE);
1135 }
1136 bs = blk_bs(blk);
1137
1138 blk_set_enable_write_cache(blk, !writethrough);
1139
1140 if (sn_opts) {
1141 ret = bdrv_snapshot_load_tmp(bs,
1142 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1143 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1144 &local_err);
1145 } else if (sn_id_or_name) {
1146 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1147 &local_err);
1148 }
1149 if (ret < 0) {
1150 error_reportf_err(local_err, "Failed to load snapshot: ");
1151 exit(EXIT_FAILURE);
1152 }
1153
1154 bs->detect_zeroes = detect_zeroes;
1155 fd_size = blk_getlength(blk);
1156 if (fd_size < 0) {
1157 error_report("Failed to determine the image length: %s",
1158 strerror(-fd_size));
1159 exit(EXIT_FAILURE);
1160 }
1161
1162 if (dev_offset >= fd_size) {
1163 error_report("Offset (%" PRIu64 ") has to be smaller than the image "
1164 "size (%" PRId64 ")", dev_offset, fd_size);
1165 exit(EXIT_FAILURE);
1166 }
1167 fd_size -= dev_offset;
1168
1169 if (partition) {
1170 uint64_t limit;
1171
1172 if (dev_offset) {
1173 error_report("Cannot request partition and offset together");
1174 exit(EXIT_FAILURE);
1175 }
1176 ret = find_partition(blk, partition, &dev_offset, &limit);
1177 if (ret < 0) {
1178 error_report("Could not find partition %d: %s", partition,
1179 strerror(-ret));
1180 exit(EXIT_FAILURE);
1181 }
1182 /*
1183 * MBR partition limits are (32-bit << 9); this assert lets
1184 * the compiler know that we can't overflow 64 bits.
1185 */
1186 assert(dev_offset + limit >= dev_offset);
1187 if (dev_offset + limit > fd_size) {
1188 error_report("Discovered partition %d at offset %" PRIu64
1189 " size %" PRIu64 ", but size exceeds file length %"
1190 PRId64, partition, dev_offset, limit, fd_size);
1191 exit(EXIT_FAILURE);
1192 }
1193 fd_size = limit;
1194 }
1195
1196 export = nbd_export_new(bs, dev_offset, fd_size, export_name,
1197 export_description, bitmap, readonly, shared > 1,
1198 nbd_export_closed, writethrough, NULL,
1199 &error_fatal);
1200
1201 if (device) {
1202 #if HAVE_NBD_DEVICE
1203 int ret;
1204
1205 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1206 if (ret != 0) {
1207 error_report("Failed to create client thread: %s", strerror(ret));
1208 exit(EXIT_FAILURE);
1209 }
1210 #endif
1211 } else {
1212 /* Shut up GCC warnings. */
1213 memset(&client_thread, 0, sizeof(client_thread));
1214 }
1215
1216 nbd_update_server_watch();
1217
1218 if (pid_file_name) {
1219 qemu_write_pidfile(pid_file_name, &error_fatal);
1220 }
1221
1222 /* now when the initialization is (almost) complete, chdir("/")
1223 * to free any busy filesystems */
1224 if (chdir("/") < 0) {
1225 error_report("Could not chdir to root directory: %s",
1226 strerror(errno));
1227 exit(EXIT_FAILURE);
1228 }
1229
1230 if (fork_process) {
1231 dup2(old_stderr, STDERR_FILENO);
1232 close(old_stderr);
1233 }
1234
1235 state = RUNNING;
1236 do {
1237 main_loop_wait(false);
1238 if (state == TERMINATE) {
1239 state = TERMINATING;
1240 nbd_export_close(export);
1241 nbd_export_put(export);
1242 export = NULL;
1243 }
1244 } while (state != TERMINATED);
1245
1246 blk_unref(blk);
1247 if (sockpath) {
1248 unlink(sockpath);
1249 }
1250
1251 qemu_opts_del(sn_opts);
1252
1253 if (device) {
1254 void *ret;
1255 pthread_join(client_thread, &ret);
1256 exit(ret != NULL);
1257 } else {
1258 exit(EXIT_SUCCESS);
1259 }
1260 }
1261