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