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