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 [NBD_FLAG_BLOCK_STAT_PAYLOAD_BIT] = "block-status-payload", 223 }; 224 225 printf(" size: %" PRIu64 "\n", list[i].size); 226 printf(" flags: 0x%x (", list[i].flags); 227 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 228 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 229 printf(" %s", flag_names[bit]); 230 } 231 } 232 printf(" )\n"); 233 } 234 if (list[i].min_block) { 235 printf(" min block: %u\n", list[i].min_block); 236 printf(" opt block: %u\n", list[i].opt_block); 237 printf(" max block: %u\n", list[i].max_block); 238 } 239 printf(" transaction size: %s\n", 240 list[i].mode >= NBD_MODE_EXTENDED ? 241 "64-bit" : "32-bit"); 242 if (list[i].n_contexts) { 243 printf(" available meta contexts: %d\n", list[i].n_contexts); 244 for (j = 0; j < list[i].n_contexts; j++) { 245 printf(" %s\n", list[i].contexts[j]); 246 } 247 } 248 } 249 nbd_free_export_list(list, rc); 250 251 ret = EXIT_SUCCESS; 252 out: 253 object_unref(OBJECT(sioc)); 254 return ret; 255 } 256 257 258 struct NbdClientOpts { 259 char *device; 260 char *srcpath; 261 SocketAddress *saddr; 262 int old_stderr; 263 bool fork_process; 264 bool verbose; 265 }; 266 267 static void nbd_client_release_pipe(int old_stderr) 268 { 269 /* Close stderr so that the qemu-nbd process exits. */ 270 if (dup2(old_stderr, STDERR_FILENO) < 0) { 271 error_report("Could not release pipe to parent: %s", 272 strerror(errno)); 273 exit(EXIT_FAILURE); 274 } 275 if (old_stderr != STDOUT_FILENO && close(old_stderr) < 0) { 276 error_report("Could not release qemu-nbd: %s", strerror(errno)); 277 exit(EXIT_FAILURE); 278 } 279 } 280 281 #if HAVE_NBD_DEVICE 282 static void *show_parts(void *arg) 283 { 284 char *device = arg; 285 int nbd; 286 287 /* linux just needs an open() to trigger 288 * the partition table update 289 * but remember to load the module with max_part != 0 : 290 * modprobe nbd max_part=63 291 */ 292 nbd = open(device, O_RDWR); 293 if (nbd >= 0) { 294 close(nbd); 295 } 296 return NULL; 297 } 298 299 static void *nbd_client_thread(void *arg) 300 { 301 struct NbdClientOpts *opts = arg; 302 /* TODO: Revisit this if nbd.ko ever gains support for structured reply */ 303 NBDExportInfo info = { .request_sizes = false, .name = g_strdup(""), 304 .mode = NBD_MODE_SIMPLE }; 305 QIOChannelSocket *sioc; 306 int fd = -1; 307 int ret = EXIT_FAILURE; 308 pthread_t show_parts_thread; 309 Error *local_error = NULL; 310 311 sioc = qio_channel_socket_new(); 312 if (qio_channel_socket_connect_sync(sioc, 313 opts->saddr, 314 &local_error) < 0) { 315 error_report_err(local_error); 316 goto out; 317 } 318 319 if (nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, NULL, NULL, 320 &info, &local_error) < 0) { 321 if (local_error) { 322 error_report_err(local_error); 323 } 324 goto out; 325 } 326 327 fd = open(opts->device, O_RDWR); 328 if (fd < 0) { 329 /* Linux-only, we can use %m in printf. */ 330 error_report("Failed to open %s: %m", opts->device); 331 goto out; 332 } 333 334 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 335 error_report_err(local_error); 336 goto out; 337 } 338 339 /* update partition table */ 340 pthread_create(&show_parts_thread, NULL, show_parts, opts->device); 341 342 if (opts->verbose && !opts->fork_process) { 343 fprintf(stderr, "NBD device %s is now connected to %s\n", 344 opts->device, opts->srcpath); 345 } else { 346 nbd_client_release_pipe(opts->old_stderr); 347 } 348 349 if (nbd_client(fd) < 0) { 350 goto out; 351 } 352 353 ret = EXIT_SUCCESS; 354 355 out: 356 if (fd >= 0) { 357 close(fd); 358 } 359 object_unref(OBJECT(sioc)); 360 g_free(info.name); 361 kill(getpid(), SIGTERM); 362 return (void *) (intptr_t) ret; 363 } 364 #endif /* HAVE_NBD_DEVICE */ 365 366 static int nbd_can_accept(void) 367 { 368 return state == RUNNING && (shared == 0 || nb_fds < shared); 369 } 370 371 static void nbd_update_server_watch(void); 372 373 static void nbd_client_closed(NBDClient *client, bool negotiated) 374 { 375 nb_fds--; 376 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 377 state = TERMINATE; 378 } 379 nbd_update_server_watch(); 380 nbd_client_put(client); 381 } 382 383 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 384 gpointer opaque) 385 { 386 if (state >= TERMINATE) { 387 return; 388 } 389 390 nb_fds++; 391 nbd_update_server_watch(); 392 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 393 } 394 395 static void nbd_update_server_watch(void) 396 { 397 if (nbd_can_accept()) { 398 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 399 } else { 400 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 401 } 402 } 403 404 405 static SocketAddress *nbd_build_socket_address(const char *sockpath, 406 const char *bindto, 407 const char *port) 408 { 409 SocketAddress *saddr; 410 411 saddr = g_new0(SocketAddress, 1); 412 if (sockpath) { 413 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 414 saddr->u.q_unix.path = g_strdup(sockpath); 415 } else { 416 InetSocketAddress *inet; 417 saddr->type = SOCKET_ADDRESS_TYPE_INET; 418 inet = &saddr->u.inet; 419 inet->host = g_strdup(bindto); 420 if (port) { 421 inet->port = g_strdup(port); 422 } else { 423 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 424 } 425 } 426 427 return saddr; 428 } 429 430 431 static QemuOptsList file_opts = { 432 .name = "file", 433 .implied_opt_name = "file", 434 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 435 .desc = { 436 /* no elements => accept any params */ 437 { /* end of list */ } 438 }, 439 }; 440 441 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 442 Error **errp) 443 { 444 Object *obj; 445 QCryptoTLSCreds *creds; 446 447 obj = object_resolve_path_component( 448 object_get_objects_root(), id); 449 if (!obj) { 450 error_setg(errp, "No TLS credentials with id '%s'", 451 id); 452 return NULL; 453 } 454 creds = (QCryptoTLSCreds *) 455 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 456 if (!creds) { 457 error_setg(errp, "Object with id '%s' is not TLS credentials", 458 id); 459 return NULL; 460 } 461 462 if (!qcrypto_tls_creds_check_endpoint(creds, 463 list 464 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT 465 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, 466 errp)) { 467 return NULL; 468 } 469 object_ref(obj); 470 return creds; 471 } 472 473 static void setup_address_and_port(const char **address, const char **port) 474 { 475 if (*address == NULL) { 476 *address = "0.0.0.0"; 477 } 478 479 if (*port == NULL) { 480 *port = stringify(NBD_DEFAULT_PORT); 481 } 482 } 483 484 /* 485 * Check socket parameters compatibility when socket activation is used. 486 */ 487 static const char *socket_activation_validate_opts(const char *device, 488 const char *sockpath, 489 const char *address, 490 const char *port, 491 const char *selinux, 492 bool list) 493 { 494 if (device != NULL) { 495 return "NBD device can't be set when using socket activation"; 496 } 497 498 if (sockpath != NULL) { 499 return "Unix socket can't be set when using socket activation"; 500 } 501 502 if (address != NULL) { 503 return "The interface can't be set when using socket activation"; 504 } 505 506 if (port != NULL) { 507 return "TCP port number can't be set when using socket activation"; 508 } 509 510 if (selinux != NULL) { 511 return "SELinux label can't be set when using socket activation"; 512 } 513 514 if (list) { 515 return "List mode is incompatible with socket activation"; 516 } 517 518 return NULL; 519 } 520 521 static void qemu_nbd_shutdown(void) 522 { 523 job_cancel_sync_all(); 524 blk_exp_close_all(); 525 bdrv_close_all(); 526 } 527 528 int main(int argc, char **argv) 529 { 530 BlockBackend *blk; 531 BlockDriverState *bs; 532 uint64_t dev_offset = 0; 533 bool readonly = false; 534 bool disconnect = false; 535 const char *bindto = NULL; 536 const char *port = NULL; 537 char *sockpath = NULL; 538 QemuOpts *sn_opts = NULL; 539 const char *sn_id_or_name = NULL; 540 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 541 struct option lopt[] = { 542 { "help", no_argument, NULL, 'h' }, 543 { "version", no_argument, NULL, 'V' }, 544 { "bind", required_argument, NULL, 'b' }, 545 { "port", required_argument, NULL, 'p' }, 546 { "socket", required_argument, NULL, 'k' }, 547 { "offset", required_argument, NULL, 'o' }, 548 { "read-only", no_argument, NULL, 'r' }, 549 { "allocation-depth", no_argument, NULL, 'A' }, 550 { "bitmap", required_argument, NULL, 'B' }, 551 { "connect", required_argument, NULL, 'c' }, 552 { "disconnect", no_argument, NULL, 'd' }, 553 { "list", no_argument, NULL, 'L' }, 554 { "snapshot", no_argument, NULL, 's' }, 555 { "load-snapshot", required_argument, NULL, 'l' }, 556 { "nocache", no_argument, NULL, 'n' }, 557 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 558 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 559 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 560 { "detect-zeroes", required_argument, NULL, 561 QEMU_NBD_OPT_DETECT_ZEROES }, 562 { "shared", required_argument, NULL, 'e' }, 563 { "format", required_argument, NULL, 'f' }, 564 { "persistent", no_argument, NULL, 't' }, 565 { "verbose", no_argument, NULL, 'v' }, 566 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 567 { "export-name", required_argument, NULL, 'x' }, 568 { "description", required_argument, NULL, 'D' }, 569 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 570 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME }, 571 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 572 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 573 { "trace", required_argument, NULL, 'T' }, 574 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 575 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 576 { "selinux-label", required_argument, NULL, 577 QEMU_NBD_OPT_SELINUX_LABEL }, 578 { NULL, 0, NULL, 0 } 579 }; 580 int ch; 581 int opt_ind = 0; 582 int flags = BDRV_O_RDWR; 583 int ret = 0; 584 bool seen_cache = false; 585 bool seen_discard = false; 586 bool seen_aio = false; 587 pthread_t client_thread; 588 const char *fmt = NULL; 589 Error *local_err = NULL; 590 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 591 QDict *options = NULL; 592 const char *export_name = NULL; /* defaults to "" later for server mode */ 593 const char *export_description = NULL; 594 BlockDirtyBitmapOrStrList *bitmaps = NULL; 595 bool alloc_depth = false; 596 const char *tlscredsid = NULL; 597 const char *tlshostname = NULL; 598 bool imageOpts = false; 599 bool writethrough = false; /* Client will flush as needed. */ 600 bool list = false; 601 unsigned socket_activation; 602 const char *pid_file_name = NULL; 603 const char *selinux_label = NULL; 604 BlockExportOptions *export_opts; 605 struct NbdClientOpts opts = { 606 .fork_process = false, 607 .verbose = false, 608 .device = NULL, 609 .srcpath = NULL, 610 .saddr = NULL, 611 .old_stderr = STDOUT_FILENO, 612 }; 613 614 #ifdef CONFIG_POSIX 615 os_setup_early_signal_handling(); 616 os_setup_signal_handling(); 617 #endif 618 619 socket_init(); 620 error_init(argv[0]); 621 module_call_init(MODULE_INIT_TRACE); 622 qcrypto_init(&error_fatal); 623 624 module_call_init(MODULE_INIT_QOM); 625 qemu_add_opts(&qemu_trace_opts); 626 qemu_init_exec_dir(argv[0]); 627 628 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 629 switch (ch) { 630 case 's': 631 flags |= BDRV_O_SNAPSHOT; 632 break; 633 case 'n': 634 optarg = (char *) "none"; 635 /* fallthrough */ 636 case QEMU_NBD_OPT_CACHE: 637 if (seen_cache) { 638 error_report("-n and --cache can only be specified once"); 639 exit(EXIT_FAILURE); 640 } 641 seen_cache = true; 642 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 643 error_report("Invalid cache mode `%s'", optarg); 644 exit(EXIT_FAILURE); 645 } 646 break; 647 case QEMU_NBD_OPT_AIO: 648 if (seen_aio) { 649 error_report("--aio can only be specified once"); 650 exit(EXIT_FAILURE); 651 } 652 seen_aio = true; 653 if (bdrv_parse_aio(optarg, &flags) < 0) { 654 error_report("Invalid aio mode '%s'", optarg); 655 exit(EXIT_FAILURE); 656 } 657 break; 658 case QEMU_NBD_OPT_DISCARD: 659 if (seen_discard) { 660 error_report("--discard can only be specified once"); 661 exit(EXIT_FAILURE); 662 } 663 seen_discard = true; 664 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 665 error_report("Invalid discard mode `%s'", optarg); 666 exit(EXIT_FAILURE); 667 } 668 break; 669 case QEMU_NBD_OPT_DETECT_ZEROES: 670 detect_zeroes = 671 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 672 optarg, 673 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 674 &local_err); 675 if (local_err) { 676 error_reportf_err(local_err, 677 "Failed to parse detect_zeroes mode: "); 678 exit(EXIT_FAILURE); 679 } 680 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 681 !(flags & BDRV_O_UNMAP)) { 682 error_report("setting detect-zeroes to unmap is not allowed " 683 "without setting discard operation to unmap"); 684 exit(EXIT_FAILURE); 685 } 686 break; 687 case 'b': 688 bindto = optarg; 689 break; 690 case 'p': 691 port = optarg; 692 break; 693 case 'o': 694 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 695 error_report("Invalid offset '%s'", optarg); 696 exit(EXIT_FAILURE); 697 } 698 break; 699 case 'l': 700 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 701 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 702 optarg, false); 703 if (!sn_opts) { 704 error_report("Failed in parsing snapshot param `%s'", 705 optarg); 706 exit(EXIT_FAILURE); 707 } 708 } else { 709 sn_id_or_name = optarg; 710 } 711 /* fall through */ 712 case 'r': 713 readonly = true; 714 flags &= ~BDRV_O_RDWR; 715 break; 716 case 'A': 717 alloc_depth = true; 718 break; 719 case 'B': 720 { 721 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1); 722 *el = (BlockDirtyBitmapOrStr) { 723 .type = QTYPE_QSTRING, 724 .u.local = g_strdup(optarg), 725 }; 726 QAPI_LIST_PREPEND(bitmaps, el); 727 } 728 break; 729 case 'k': 730 sockpath = optarg; 731 if (sockpath[0] != '/') { 732 error_report("socket path must be absolute"); 733 exit(EXIT_FAILURE); 734 } 735 break; 736 case 'd': 737 disconnect = true; 738 break; 739 case 'c': 740 opts.device = optarg; 741 break; 742 case 'e': 743 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 744 shared < 0) { 745 error_report("Invalid shared device number '%s'", optarg); 746 exit(EXIT_FAILURE); 747 } 748 break; 749 case 'f': 750 fmt = optarg; 751 break; 752 case 't': 753 persistent = 1; 754 break; 755 case 'x': 756 export_name = optarg; 757 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 758 error_report("export name '%s' too long", export_name); 759 exit(EXIT_FAILURE); 760 } 761 break; 762 case 'D': 763 export_description = optarg; 764 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 765 error_report("export description '%s' too long", 766 export_description); 767 exit(EXIT_FAILURE); 768 } 769 break; 770 case 'v': 771 opts.verbose = true; 772 break; 773 case 'V': 774 version(argv[0]); 775 exit(0); 776 break; 777 case 'h': 778 usage(argv[0]); 779 exit(0); 780 break; 781 case '?': 782 error_report("Try `%s --help' for more information.", argv[0]); 783 exit(EXIT_FAILURE); 784 case QEMU_NBD_OPT_OBJECT: 785 user_creatable_process_cmdline(optarg); 786 break; 787 case QEMU_NBD_OPT_TLSCREDS: 788 tlscredsid = optarg; 789 break; 790 case QEMU_NBD_OPT_TLSHOSTNAME: 791 tlshostname = optarg; 792 break; 793 case QEMU_NBD_OPT_IMAGE_OPTS: 794 imageOpts = true; 795 break; 796 case 'T': 797 trace_opt_parse(optarg); 798 break; 799 case QEMU_NBD_OPT_TLSAUTHZ: 800 tlsauthz = optarg; 801 break; 802 case QEMU_NBD_OPT_FORK: 803 opts.fork_process = true; 804 break; 805 case 'L': 806 list = true; 807 break; 808 case QEMU_NBD_OPT_PID_FILE: 809 pid_file_name = optarg; 810 break; 811 case QEMU_NBD_OPT_SELINUX_LABEL: 812 selinux_label = optarg; 813 break; 814 } 815 } 816 817 if (list) { 818 if (argc != optind) { 819 error_report("List mode is incompatible with a file name"); 820 exit(EXIT_FAILURE); 821 } 822 if (export_name || export_description || dev_offset || 823 opts.device || disconnect || fmt || sn_id_or_name || bitmaps || 824 alloc_depth || seen_aio || seen_discard || seen_cache) { 825 error_report("List mode is incompatible with per-device settings"); 826 exit(EXIT_FAILURE); 827 } 828 if (opts.fork_process) { 829 error_report("List mode is incompatible with forking"); 830 exit(EXIT_FAILURE); 831 } 832 } else if ((argc - optind) != 1) { 833 error_report("Invalid number of arguments"); 834 error_printf("Try `%s --help' for more information.\n", argv[0]); 835 exit(EXIT_FAILURE); 836 } else if (!export_name) { 837 export_name = ""; 838 } 839 840 if (!trace_init_backends()) { 841 exit(1); 842 } 843 trace_init_file(); 844 qemu_set_log(LOG_TRACE, &error_fatal); 845 846 socket_activation = check_socket_activation(); 847 if (socket_activation == 0) { 848 if (!sockpath) { 849 setup_address_and_port(&bindto, &port); 850 } 851 } else { 852 /* Using socket activation - check user didn't use -p etc. */ 853 const char *err_msg = socket_activation_validate_opts(opts.device, 854 sockpath, 855 bindto, port, 856 selinux_label, 857 list); 858 if (err_msg != NULL) { 859 error_report("%s", err_msg); 860 exit(EXIT_FAILURE); 861 } 862 863 /* qemu-nbd can only listen on a single socket. */ 864 if (socket_activation > 1) { 865 error_report("qemu-nbd does not support socket activation with %s > 1", 866 "LISTEN_FDS"); 867 exit(EXIT_FAILURE); 868 } 869 } 870 871 if (tlscredsid) { 872 if (opts.device) { 873 error_report("TLS is not supported with a host device"); 874 exit(EXIT_FAILURE); 875 } 876 if (tlsauthz && list) { 877 error_report("TLS authorization is incompatible with export list"); 878 exit(EXIT_FAILURE); 879 } 880 if (tlshostname && !list) { 881 error_report("TLS hostname is only supported with export list"); 882 exit(EXIT_FAILURE); 883 } 884 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 885 if (local_err) { 886 error_reportf_err(local_err, "Failed to get TLS creds: "); 887 exit(EXIT_FAILURE); 888 } 889 } else { 890 if (tlsauthz) { 891 error_report("--tls-authz is not permitted without --tls-creds"); 892 exit(EXIT_FAILURE); 893 } 894 if (tlshostname) { 895 error_report("--tls-hostname is not permitted without --tls-creds"); 896 exit(EXIT_FAILURE); 897 } 898 } 899 900 if (selinux_label) { 901 #ifdef CONFIG_SELINUX 902 if (sockpath == NULL && opts.device == NULL) { 903 error_report("--selinux-label is not permitted without --socket"); 904 exit(EXIT_FAILURE); 905 } 906 #else 907 error_report("SELinux support not enabled in this binary"); 908 exit(EXIT_FAILURE); 909 #endif 910 } 911 912 if (list) { 913 opts.saddr = nbd_build_socket_address(sockpath, bindto, port); 914 return qemu_nbd_client_list(opts.saddr, tlscreds, 915 tlshostname ? tlshostname : bindto); 916 } 917 918 #if !HAVE_NBD_DEVICE 919 if (disconnect || opts.device) { 920 error_report("Kernel /dev/nbdN support not available"); 921 exit(EXIT_FAILURE); 922 } 923 #else /* HAVE_NBD_DEVICE */ 924 if (disconnect) { 925 int nbdfd = open(argv[optind], O_RDWR); 926 if (nbdfd < 0) { 927 error_report("Cannot open %s: %s", argv[optind], 928 strerror(errno)); 929 exit(EXIT_FAILURE); 930 } 931 nbd_disconnect(nbdfd); 932 933 close(nbdfd); 934 935 printf("%s disconnected\n", argv[optind]); 936 937 return 0; 938 } 939 #endif 940 941 if ((opts.device && !opts.verbose) || opts.fork_process) { 942 #ifndef WIN32 943 g_autoptr(GError) err = NULL; 944 int stderr_fd[2]; 945 pid_t pid; 946 947 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) { 948 error_report("Error setting up communication pipe: %s", 949 err->message); 950 exit(EXIT_FAILURE); 951 } 952 953 /* Now daemonize, but keep a communication channel open to 954 * print errors and exit with the proper status code. 955 */ 956 pid = fork(); 957 if (pid < 0) { 958 error_report("Failed to fork: %s", strerror(errno)); 959 exit(EXIT_FAILURE); 960 } else if (pid == 0) { 961 int saved_errno; 962 963 close(stderr_fd[0]); 964 965 /* Remember parent's stderr if we will be restoring it. */ 966 if (opts.verbose /* fork_process is set */) { 967 opts.old_stderr = dup(STDERR_FILENO); 968 if (opts.old_stderr < 0) { 969 error_report("Could not dup original stderr: %s", 970 strerror(errno)); 971 exit(EXIT_FAILURE); 972 } 973 } 974 975 ret = qemu_daemon(1, 0); 976 saved_errno = errno; /* dup2 will overwrite error below */ 977 978 /* Temporarily redirect stderr to the parent's pipe... */ 979 if (dup2(stderr_fd[1], STDERR_FILENO) < 0) { 980 char str[256]; 981 snprintf(str, sizeof(str), 982 "%s: Failed to link stderr to the pipe: %s\n", 983 g_get_prgname(), strerror(errno)); 984 /* 985 * We are unable to use error_report() here as we need to get 986 * stderr pointed to the parent's pipe. Write to that pipe 987 * manually. 988 */ 989 ret = write(stderr_fd[1], str, strlen(str)); 990 exit(EXIT_FAILURE); 991 } 992 993 if (ret < 0) { 994 error_report("Failed to daemonize: %s", strerror(saved_errno)); 995 exit(EXIT_FAILURE); 996 } 997 998 /* ... close the descriptor we inherited and go on. */ 999 close(stderr_fd[1]); 1000 } else { 1001 bool errors = false; 1002 char *buf; 1003 1004 /* In the parent. Print error messages from the child until 1005 * it closes the pipe. 1006 */ 1007 close(stderr_fd[1]); 1008 buf = g_malloc(1024); 1009 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 1010 errors = true; 1011 ret = qemu_write_full(STDERR_FILENO, buf, ret); 1012 if (ret < 0) { 1013 exit(EXIT_FAILURE); 1014 } 1015 } 1016 if (ret < 0) { 1017 error_report("Cannot read from daemon: %s", 1018 strerror(errno)); 1019 exit(EXIT_FAILURE); 1020 } 1021 1022 /* Usually the daemon should not print any message. 1023 * Exit with zero status in that case. 1024 */ 1025 exit(errors); 1026 } 1027 #else /* WIN32 */ 1028 error_report("Unable to fork into background on Windows hosts"); 1029 exit(EXIT_FAILURE); 1030 #endif /* WIN32 */ 1031 } 1032 1033 if (opts.device != NULL && sockpath == NULL) { 1034 sockpath = g_malloc(128); 1035 snprintf(sockpath, 128, SOCKET_PATH, basename(opts.device)); 1036 } 1037 1038 server = qio_net_listener_new(); 1039 if (socket_activation == 0) { 1040 int backlog; 1041 1042 if (persistent || shared == 0) { 1043 backlog = SOMAXCONN; 1044 } else { 1045 backlog = MIN(shared, SOMAXCONN); 1046 } 1047 #ifdef CONFIG_SELINUX 1048 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) { 1049 error_report("Cannot set SELinux socket create context to %s: %s", 1050 selinux_label, strerror(errno)); 1051 exit(EXIT_FAILURE); 1052 } 1053 #endif 1054 opts.saddr = nbd_build_socket_address(sockpath, bindto, port); 1055 if (qio_net_listener_open_sync(server, opts.saddr, backlog, 1056 &local_err) < 0) { 1057 object_unref(OBJECT(server)); 1058 error_report_err(local_err); 1059 exit(EXIT_FAILURE); 1060 } 1061 #ifdef CONFIG_SELINUX 1062 if (selinux_label && setsockcreatecon_raw(NULL) == -1) { 1063 error_report("Cannot clear SELinux socket create context: %s", 1064 strerror(errno)); 1065 exit(EXIT_FAILURE); 1066 } 1067 #endif 1068 } else { 1069 size_t i; 1070 /* See comment in check_socket_activation above. */ 1071 for (i = 0; i < socket_activation; i++) { 1072 QIOChannelSocket *sioc; 1073 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 1074 &local_err); 1075 if (sioc == NULL) { 1076 object_unref(OBJECT(server)); 1077 error_reportf_err(local_err, 1078 "Failed to use socket activation: "); 1079 exit(EXIT_FAILURE); 1080 } 1081 qio_net_listener_add(server, sioc); 1082 object_unref(OBJECT(sioc)); 1083 } 1084 } 1085 1086 qemu_init_main_loop(&error_fatal); 1087 bdrv_init(); 1088 atexit(qemu_nbd_shutdown); 1089 1090 opts.srcpath = argv[optind]; 1091 if (imageOpts) { 1092 QemuOpts *o; 1093 if (fmt) { 1094 error_report("--image-opts and -f are mutually exclusive"); 1095 exit(EXIT_FAILURE); 1096 } 1097 o = qemu_opts_parse_noisily(&file_opts, opts.srcpath, true); 1098 if (!o) { 1099 qemu_opts_reset(&file_opts); 1100 exit(EXIT_FAILURE); 1101 } 1102 options = qemu_opts_to_qdict(o, NULL); 1103 qemu_opts_reset(&file_opts); 1104 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1105 } else { 1106 if (fmt) { 1107 options = qdict_new(); 1108 qdict_put_str(options, "driver", fmt); 1109 } 1110 blk = blk_new_open(opts.srcpath, NULL, options, flags, &local_err); 1111 } 1112 1113 if (!blk) { 1114 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1115 argv[optind]); 1116 exit(EXIT_FAILURE); 1117 } 1118 bs = blk_bs(blk); 1119 1120 if (dev_offset) { 1121 QDict *raw_opts = qdict_new(); 1122 qdict_put_str(raw_opts, "driver", "raw"); 1123 qdict_put_str(raw_opts, "file", bs->node_name); 1124 qdict_put_int(raw_opts, "offset", dev_offset); 1125 1126 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1127 1128 blk_remove_bs(blk); 1129 blk_insert_bs(blk, bs, &error_fatal); 1130 bdrv_unref(bs); 1131 } 1132 1133 blk_set_enable_write_cache(blk, !writethrough); 1134 1135 if (sn_opts) { 1136 ret = bdrv_snapshot_load_tmp(bs, 1137 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1138 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1139 &local_err); 1140 } else if (sn_id_or_name) { 1141 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1142 &local_err); 1143 } 1144 if (ret < 0) { 1145 error_reportf_err(local_err, "Failed to load snapshot: "); 1146 exit(EXIT_FAILURE); 1147 } 1148 1149 bs->detect_zeroes = detect_zeroes; 1150 1151 nbd_server_is_qemu_nbd(shared); 1152 1153 export_opts = g_new(BlockExportOptions, 1); 1154 *export_opts = (BlockExportOptions) { 1155 .type = BLOCK_EXPORT_TYPE_NBD, 1156 .id = g_strdup("qemu-nbd-export"), 1157 .node_name = g_strdup(bdrv_get_node_name(bs)), 1158 .has_writethrough = true, 1159 .writethrough = writethrough, 1160 .has_writable = true, 1161 .writable = !readonly, 1162 .u.nbd = { 1163 .name = g_strdup(export_name), 1164 .description = g_strdup(export_description), 1165 .has_bitmaps = !!bitmaps, 1166 .bitmaps = bitmaps, 1167 .has_allocation_depth = alloc_depth, 1168 .allocation_depth = alloc_depth, 1169 }, 1170 }; 1171 blk_exp_add(export_opts, &error_fatal); 1172 qapi_free_BlockExportOptions(export_opts); 1173 1174 if (opts.device) { 1175 #if HAVE_NBD_DEVICE 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 *result; 1223 pthread_join(client_thread, &result); 1224 ret = (intptr_t)result; 1225 exit(ret); 1226 } else { 1227 exit(EXIT_SUCCESS); 1228 } 1229 } 1230