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