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