1 /* 2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws> 3 * 4 * Network Block Device 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; under version 2 of the License. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "qemu/osdep.h" 20 #include <getopt.h> 21 #include <libgen.h> 22 #include <pthread.h> 23 24 #include "qemu/help-texts.h" 25 #include "qapi/error.h" 26 #include "qemu/cutils.h" 27 #include "sysemu/block-backend.h" 28 #include "sysemu/runstate.h" /* for qemu_system_killed() prototype */ 29 #include "block/block_int.h" 30 #include "block/nbd.h" 31 #include "qemu/main-loop.h" 32 #include "qemu/module.h" 33 #include "qemu/option.h" 34 #include "qemu/error-report.h" 35 #include "qemu/config-file.h" 36 #include "qemu/bswap.h" 37 #include "qemu/log.h" 38 #include "qemu/systemd.h" 39 #include "block/snapshot.h" 40 #include "qapi/qmp/qdict.h" 41 #include "qapi/qmp/qstring.h" 42 #include "qom/object_interfaces.h" 43 #include "io/channel-socket.h" 44 #include "io/net-listener.h" 45 #include "crypto/init.h" 46 #include "crypto/tlscreds.h" 47 #include "trace/control.h" 48 #include "qemu-version.h" 49 50 #ifdef CONFIG_SELINUX 51 #include <selinux/selinux.h> 52 #endif 53 54 #ifdef __linux__ 55 #define HAVE_NBD_DEVICE 1 56 #else 57 #define HAVE_NBD_DEVICE 0 58 #endif 59 60 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 61 #define QEMU_NBD_OPT_CACHE 256 62 #define QEMU_NBD_OPT_AIO 257 63 #define QEMU_NBD_OPT_DISCARD 258 64 #define QEMU_NBD_OPT_DETECT_ZEROES 259 65 #define QEMU_NBD_OPT_OBJECT 260 66 #define QEMU_NBD_OPT_TLSCREDS 261 67 #define QEMU_NBD_OPT_IMAGE_OPTS 262 68 #define QEMU_NBD_OPT_FORK 263 69 #define QEMU_NBD_OPT_TLSAUTHZ 264 70 #define QEMU_NBD_OPT_PID_FILE 265 71 #define QEMU_NBD_OPT_SELINUX_LABEL 266 72 #define QEMU_NBD_OPT_TLSHOSTNAME 267 73 74 #define MBR_SIZE 512 75 76 static int persistent = 0; 77 static enum { RUNNING, TERMINATE, TERMINATED } state; 78 static int shared = 1; 79 static int nb_fds; 80 static QIONetListener *server; 81 static QCryptoTLSCreds *tlscreds; 82 static const char *tlsauthz; 83 84 static void usage(const char *name) 85 { 86 (printf) ( 87 "Usage: %s [OPTIONS] FILE\n" 88 " or: %s -L [OPTIONS]\n" 89 "QEMU Disk Network Block Device Utility\n" 90 "\n" 91 " -h, --help display this help and exit\n" 92 " -V, --version output version information and exit\n" 93 "\n" 94 "Connection properties:\n" 95 " -p, --port=PORT port to listen on (default `%d')\n" 96 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 97 " -k, --socket=PATH path to the unix socket\n" 98 " (default '"SOCKET_PATH"')\n" 99 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 100 " -t, --persistent don't exit on the last connection\n" 101 " -v, --verbose display extra debugging information\n" 102 " -x, --export-name=NAME expose export by name (default is empty string)\n" 103 " -D, --description=TEXT export a human-readable description\n" 104 "\n" 105 "Exposing part of the image:\n" 106 " -o, --offset=OFFSET offset into the image\n" 107 " -A, --allocation-depth expose the allocation depth\n" 108 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 109 "\n" 110 "General purpose options:\n" 111 " -L, --list list exports available from another NBD server\n" 112 " --object type,id=ID,... define an object such as 'secret' for providing\n" 113 " passwords and/or encryption keys\n" 114 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 115 " --tls-authz=ID use id of an earlier --object to provide\n" 116 " authorization\n" 117 " --tls-hostname=HOSTNAME override hostname used to check x509 certificate\n" 118 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 119 " specify tracing options\n" 120 " --fork fork off the server process and exit the parent\n" 121 " once the server is running\n" 122 " --pid-file=PATH store the server's process ID in the given file\n" 123 #ifdef CONFIG_SELINUX 124 " --selinux-label=LABEL set SELinux process label on listening socket\n" 125 #endif 126 #if HAVE_NBD_DEVICE 127 "\n" 128 "Kernel NBD client support:\n" 129 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 130 " -d, --disconnect disconnect the specified device\n" 131 #endif 132 "\n" 133 "Block device options:\n" 134 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 135 " -r, --read-only export read-only\n" 136 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 137 " file with backing_file=FILE, redirect the write to\n" 138 " the temporary one\n" 139 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 140 " load an internal snapshot inside FILE and export it\n" 141 " as an read-only device, SNAPSHOT_PARAM format is\n" 142 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 143 " '[ID_OR_NAME]'\n" 144 " -n, --nocache disable host cache\n" 145 " --cache=MODE set cache mode used to access the disk image, the\n" 146 " valid options are: 'none', 'writeback' (default),\n" 147 " 'writethrough', 'directsync' and 'unsafe'\n" 148 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 149 " --discard=MODE set discard mode (ignore, unmap)\n" 150 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 151 " --image-opts treat FILE as a full set of image options\n" 152 "\n" 153 QEMU_HELP_BOTTOM "\n" 154 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 155 } 156 157 static void version(const char *name) 158 { 159 printf( 160 "%s " QEMU_FULL_VERSION "\n" 161 "Written by Anthony Liguori.\n" 162 "\n" 163 QEMU_COPYRIGHT "\n" 164 "This is free software; see the source for copying conditions. There is NO\n" 165 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 166 , name); 167 } 168 169 #ifdef CONFIG_POSIX 170 /* 171 * The client thread uses SIGTERM to interrupt the server. A signal 172 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 173 */ 174 void qemu_system_killed(int signum, pid_t pid) 175 { 176 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 177 qemu_notify_event(); 178 } 179 #endif /* CONFIG_POSIX */ 180 181 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 182 const char *hostname) 183 { 184 int ret = EXIT_FAILURE; 185 int rc; 186 Error *err = NULL; 187 QIOChannelSocket *sioc; 188 NBDExportInfo *list; 189 int i, j; 190 191 sioc = qio_channel_socket_new(); 192 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 193 error_report_err(err); 194 goto out; 195 } 196 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 197 &err); 198 if (rc < 0) { 199 if (err) { 200 error_report_err(err); 201 } 202 goto out; 203 } 204 printf("exports available: %d\n", rc); 205 for (i = 0; i < rc; i++) { 206 printf(" export: '%s'\n", list[i].name); 207 if (list[i].description && *list[i].description) { 208 printf(" description: %s\n", list[i].description); 209 } 210 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 211 static const char *const flag_names[] = { 212 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 213 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 214 [NBD_FLAG_SEND_FUA_BIT] = "fua", 215 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 216 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 217 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 218 [NBD_FLAG_SEND_DF_BIT] = "df", 219 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 220 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 221 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 222 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 223 [NBD_FLAG_BLOCK_STAT_PAYLOAD_BIT] = "block-status-payload", 224 }; 225 226 printf(" size: %" PRIu64 "\n", list[i].size); 227 printf(" flags: 0x%x (", list[i].flags); 228 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 229 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 230 printf(" %s", flag_names[bit]); 231 } 232 } 233 printf(" )\n"); 234 } 235 if (list[i].min_block) { 236 printf(" min block: %u\n", list[i].min_block); 237 printf(" opt block: %u\n", list[i].opt_block); 238 printf(" max block: %u\n", list[i].max_block); 239 } 240 printf(" transaction size: %s\n", 241 list[i].mode >= NBD_MODE_EXTENDED ? 242 "64-bit" : "32-bit"); 243 if (list[i].n_contexts) { 244 printf(" available meta contexts: %d\n", list[i].n_contexts); 245 for (j = 0; j < list[i].n_contexts; j++) { 246 printf(" %s\n", list[i].contexts[j]); 247 } 248 } 249 } 250 nbd_free_export_list(list, rc); 251 252 ret = EXIT_SUCCESS; 253 out: 254 object_unref(OBJECT(sioc)); 255 return ret; 256 } 257 258 259 struct NbdClientOpts { 260 char *device; 261 char *srcpath; 262 SocketAddress *saddr; 263 int old_stderr; 264 bool fork_process; 265 bool verbose; 266 }; 267 268 static void nbd_client_release_pipe(int old_stderr) 269 { 270 /* Close stderr so that the qemu-nbd process exits. */ 271 if (dup2(old_stderr, STDERR_FILENO) < 0) { 272 error_report("Could not release pipe to parent: %s", 273 strerror(errno)); 274 exit(EXIT_FAILURE); 275 } 276 if (old_stderr != STDOUT_FILENO && close(old_stderr) < 0) { 277 error_report("Could not release qemu-nbd: %s", strerror(errno)); 278 exit(EXIT_FAILURE); 279 } 280 } 281 282 #if HAVE_NBD_DEVICE 283 static void *show_parts(void *arg) 284 { 285 char *device = arg; 286 int nbd; 287 288 /* linux just needs an open() to trigger 289 * the partition table update 290 * but remember to load the module with max_part != 0 : 291 * modprobe nbd max_part=63 292 */ 293 nbd = open(device, O_RDWR); 294 if (nbd >= 0) { 295 close(nbd); 296 } 297 return NULL; 298 } 299 300 static void *nbd_client_thread(void *arg) 301 { 302 struct NbdClientOpts *opts = arg; 303 /* TODO: Revisit this if nbd.ko ever gains support for structured reply */ 304 NBDExportInfo info = { .request_sizes = false, .name = g_strdup(""), 305 .mode = NBD_MODE_SIMPLE }; 306 QIOChannelSocket *sioc; 307 int fd = -1; 308 int ret = EXIT_FAILURE; 309 pthread_t show_parts_thread; 310 Error *local_error = NULL; 311 312 sioc = qio_channel_socket_new(); 313 if (qio_channel_socket_connect_sync(sioc, 314 opts->saddr, 315 &local_error) < 0) { 316 error_report_err(local_error); 317 goto out; 318 } 319 320 if (nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, NULL, NULL, 321 &info, &local_error) < 0) { 322 if (local_error) { 323 error_report_err(local_error); 324 } 325 goto out; 326 } 327 328 fd = open(opts->device, O_RDWR); 329 if (fd < 0) { 330 /* Linux-only, we can use %m in printf. */ 331 error_report("Failed to open %s: %m", opts->device); 332 goto out; 333 } 334 335 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 336 error_report_err(local_error); 337 goto out; 338 } 339 340 /* update partition table */ 341 pthread_create(&show_parts_thread, NULL, show_parts, opts->device); 342 343 if (opts->verbose && !opts->fork_process) { 344 fprintf(stderr, "NBD device %s is now connected to %s\n", 345 opts->device, opts->srcpath); 346 } else { 347 nbd_client_release_pipe(opts->old_stderr); 348 } 349 350 if (nbd_client(fd) < 0) { 351 goto out; 352 } 353 354 ret = EXIT_SUCCESS; 355 356 out: 357 if (fd >= 0) { 358 close(fd); 359 } 360 object_unref(OBJECT(sioc)); 361 g_free(info.name); 362 kill(getpid(), SIGTERM); 363 return (void *) (intptr_t) ret; 364 } 365 #endif /* HAVE_NBD_DEVICE */ 366 367 static int nbd_can_accept(void) 368 { 369 return state == RUNNING && (shared == 0 || nb_fds < shared); 370 } 371 372 static void nbd_update_server_watch(void); 373 374 static void nbd_client_closed(NBDClient *client, bool negotiated) 375 { 376 nb_fds--; 377 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 378 state = TERMINATE; 379 } 380 nbd_update_server_watch(); 381 nbd_client_put(client); 382 } 383 384 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 385 gpointer opaque) 386 { 387 if (state >= TERMINATE) { 388 return; 389 } 390 391 nb_fds++; 392 nbd_update_server_watch(); 393 /* TODO - expose handshake timeout as command line option */ 394 nbd_client_new(cioc, NBD_DEFAULT_HANDSHAKE_MAX_SECS, 395 tlscreds, tlsauthz, nbd_client_closed, NULL); 396 } 397 398 static void nbd_update_server_watch(void) 399 { 400 if (nbd_can_accept()) { 401 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 402 } else { 403 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 404 } 405 } 406 407 408 static SocketAddress *nbd_build_socket_address(const char *sockpath, 409 const char *bindto, 410 const char *port) 411 { 412 SocketAddress *saddr; 413 414 saddr = g_new0(SocketAddress, 1); 415 if (sockpath) { 416 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 417 saddr->u.q_unix.path = g_strdup(sockpath); 418 } else { 419 InetSocketAddress *inet; 420 saddr->type = SOCKET_ADDRESS_TYPE_INET; 421 inet = &saddr->u.inet; 422 inet->host = g_strdup(bindto); 423 if (port) { 424 inet->port = g_strdup(port); 425 } else { 426 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 427 } 428 } 429 430 return saddr; 431 } 432 433 434 static QemuOptsList file_opts = { 435 .name = "file", 436 .implied_opt_name = "file", 437 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 438 .desc = { 439 /* no elements => accept any params */ 440 { /* end of list */ } 441 }, 442 }; 443 444 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 445 Error **errp) 446 { 447 Object *obj; 448 QCryptoTLSCreds *creds; 449 450 obj = object_resolve_path_component( 451 object_get_objects_root(), id); 452 if (!obj) { 453 error_setg(errp, "No TLS credentials with id '%s'", 454 id); 455 return NULL; 456 } 457 creds = (QCryptoTLSCreds *) 458 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 459 if (!creds) { 460 error_setg(errp, "Object with id '%s' is not TLS credentials", 461 id); 462 return NULL; 463 } 464 465 if (!qcrypto_tls_creds_check_endpoint(creds, 466 list 467 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT 468 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, 469 errp)) { 470 return NULL; 471 } 472 object_ref(obj); 473 return creds; 474 } 475 476 static void setup_address_and_port(const char **address, const char **port) 477 { 478 if (*address == NULL) { 479 *address = "0.0.0.0"; 480 } 481 482 if (*port == NULL) { 483 *port = stringify(NBD_DEFAULT_PORT); 484 } 485 } 486 487 /* 488 * Check socket parameters compatibility when socket activation is used. 489 */ 490 static const char *socket_activation_validate_opts(const char *device, 491 const char *sockpath, 492 const char *address, 493 const char *port, 494 const char *selinux, 495 bool list) 496 { 497 if (device != NULL) { 498 return "NBD device can't be set when using socket activation"; 499 } 500 501 if (sockpath != NULL) { 502 return "Unix socket can't be set when using socket activation"; 503 } 504 505 if (address != NULL) { 506 return "The interface can't be set when using socket activation"; 507 } 508 509 if (port != NULL) { 510 return "TCP port number can't be set when using socket activation"; 511 } 512 513 if (selinux != NULL) { 514 return "SELinux label can't be set when using socket activation"; 515 } 516 517 if (list) { 518 return "List mode is incompatible with socket activation"; 519 } 520 521 return NULL; 522 } 523 524 static void qemu_nbd_shutdown(void) 525 { 526 job_cancel_sync_all(); 527 blk_exp_close_all(); 528 bdrv_close_all(); 529 } 530 531 int main(int argc, char **argv) 532 { 533 BlockBackend *blk; 534 BlockDriverState *bs; 535 uint64_t dev_offset = 0; 536 bool readonly = false; 537 bool disconnect = false; 538 const char *bindto = NULL; 539 const char *port = NULL; 540 char *sockpath = NULL; 541 QemuOpts *sn_opts = NULL; 542 const char *sn_id_or_name = NULL; 543 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 544 struct option lopt[] = { 545 { "help", no_argument, NULL, 'h' }, 546 { "version", no_argument, NULL, 'V' }, 547 { "bind", required_argument, NULL, 'b' }, 548 { "port", required_argument, NULL, 'p' }, 549 { "socket", required_argument, NULL, 'k' }, 550 { "offset", required_argument, NULL, 'o' }, 551 { "read-only", no_argument, NULL, 'r' }, 552 { "allocation-depth", no_argument, NULL, 'A' }, 553 { "bitmap", required_argument, NULL, 'B' }, 554 { "connect", required_argument, NULL, 'c' }, 555 { "disconnect", no_argument, NULL, 'd' }, 556 { "list", no_argument, NULL, 'L' }, 557 { "snapshot", no_argument, NULL, 's' }, 558 { "load-snapshot", required_argument, NULL, 'l' }, 559 { "nocache", no_argument, NULL, 'n' }, 560 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 561 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 562 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 563 { "detect-zeroes", required_argument, NULL, 564 QEMU_NBD_OPT_DETECT_ZEROES }, 565 { "shared", required_argument, NULL, 'e' }, 566 { "format", required_argument, NULL, 'f' }, 567 { "persistent", no_argument, NULL, 't' }, 568 { "verbose", no_argument, NULL, 'v' }, 569 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 570 { "export-name", required_argument, NULL, 'x' }, 571 { "description", required_argument, NULL, 'D' }, 572 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 573 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME }, 574 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 575 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 576 { "trace", required_argument, NULL, 'T' }, 577 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 578 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 579 { "selinux-label", required_argument, NULL, 580 QEMU_NBD_OPT_SELINUX_LABEL }, 581 { NULL, 0, NULL, 0 } 582 }; 583 int ch; 584 int opt_ind = 0; 585 int flags = BDRV_O_RDWR; 586 int ret = 0; 587 bool seen_cache = false; 588 bool seen_discard = false; 589 bool seen_aio = false; 590 pthread_t client_thread; 591 const char *fmt = NULL; 592 Error *local_err = NULL; 593 BlockdevDetectZeroesOptions detect_zeroes = 594 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 595 QDict *options = NULL; 596 const char *export_name = NULL; /* defaults to "" later for server mode */ 597 const char *export_description = NULL; 598 BlockDirtyBitmapOrStrList *bitmaps = NULL; 599 bool alloc_depth = false; 600 const char *tlscredsid = NULL; 601 const char *tlshostname = NULL; 602 bool imageOpts = false; 603 bool writethrough = false; /* Client will flush as needed. */ 604 bool list = false; 605 unsigned socket_activation; 606 const char *pid_file_name = NULL; 607 const char *selinux_label = NULL; 608 BlockExportOptions *export_opts; 609 struct NbdClientOpts opts = { 610 .fork_process = false, 611 .verbose = false, 612 .device = NULL, 613 .srcpath = NULL, 614 .saddr = NULL, 615 .old_stderr = STDOUT_FILENO, 616 }; 617 618 #ifdef CONFIG_POSIX 619 os_setup_early_signal_handling(); 620 os_setup_signal_handling(); 621 #endif 622 623 socket_init(); 624 error_init(argv[0]); 625 module_call_init(MODULE_INIT_TRACE); 626 qcrypto_init(&error_fatal); 627 628 module_call_init(MODULE_INIT_QOM); 629 qemu_add_opts(&qemu_trace_opts); 630 qemu_init_exec_dir(argv[0]); 631 632 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 633 switch (ch) { 634 case 's': 635 flags |= BDRV_O_SNAPSHOT; 636 break; 637 case 'n': 638 optarg = (char *) "none"; 639 /* fallthrough */ 640 case QEMU_NBD_OPT_CACHE: 641 if (seen_cache) { 642 error_report("-n and --cache can only be specified once"); 643 exit(EXIT_FAILURE); 644 } 645 seen_cache = true; 646 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 647 error_report("Invalid cache mode `%s'", optarg); 648 exit(EXIT_FAILURE); 649 } 650 break; 651 case QEMU_NBD_OPT_AIO: 652 if (seen_aio) { 653 error_report("--aio can only be specified once"); 654 exit(EXIT_FAILURE); 655 } 656 seen_aio = true; 657 if (bdrv_parse_aio(optarg, &flags) < 0) { 658 error_report("Invalid aio mode '%s'", optarg); 659 exit(EXIT_FAILURE); 660 } 661 break; 662 case QEMU_NBD_OPT_DISCARD: 663 if (seen_discard) { 664 error_report("--discard can only be specified once"); 665 exit(EXIT_FAILURE); 666 } 667 seen_discard = true; 668 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 669 error_report("Invalid discard mode `%s'", optarg); 670 exit(EXIT_FAILURE); 671 } 672 break; 673 case QEMU_NBD_OPT_DETECT_ZEROES: 674 detect_zeroes = 675 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 676 optarg, 677 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 678 &local_err); 679 if (local_err) { 680 error_reportf_err(local_err, 681 "Failed to parse detect_zeroes mode: "); 682 exit(EXIT_FAILURE); 683 } 684 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 685 !(flags & BDRV_O_UNMAP)) { 686 error_report("setting detect-zeroes to unmap is not allowed " 687 "without setting discard operation to unmap"); 688 exit(EXIT_FAILURE); 689 } 690 break; 691 case 'b': 692 bindto = optarg; 693 break; 694 case 'p': 695 port = optarg; 696 break; 697 case 'o': 698 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 699 error_report("Invalid offset '%s'", optarg); 700 exit(EXIT_FAILURE); 701 } 702 break; 703 case 'l': 704 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 705 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 706 optarg, false); 707 if (!sn_opts) { 708 error_report("Failed in parsing snapshot param `%s'", 709 optarg); 710 exit(EXIT_FAILURE); 711 } 712 } else { 713 sn_id_or_name = optarg; 714 } 715 /* fall through */ 716 case 'r': 717 readonly = true; 718 flags &= ~BDRV_O_RDWR; 719 break; 720 case 'A': 721 alloc_depth = true; 722 break; 723 case 'B': 724 { 725 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1); 726 *el = (BlockDirtyBitmapOrStr) { 727 .type = QTYPE_QSTRING, 728 .u.local = g_strdup(optarg), 729 }; 730 QAPI_LIST_PREPEND(bitmaps, el); 731 } 732 break; 733 case 'k': 734 sockpath = optarg; 735 if (sockpath[0] != '/') { 736 error_report("socket path must be absolute"); 737 exit(EXIT_FAILURE); 738 } 739 break; 740 case 'd': 741 disconnect = true; 742 break; 743 case 'c': 744 opts.device = optarg; 745 break; 746 case 'e': 747 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 748 shared < 0) { 749 error_report("Invalid shared device number '%s'", optarg); 750 exit(EXIT_FAILURE); 751 } 752 break; 753 case 'f': 754 fmt = optarg; 755 break; 756 case 't': 757 persistent = 1; 758 break; 759 case 'x': 760 export_name = optarg; 761 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 762 error_report("export name '%s' too long", export_name); 763 exit(EXIT_FAILURE); 764 } 765 break; 766 case 'D': 767 export_description = optarg; 768 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 769 error_report("export description '%s' too long", 770 export_description); 771 exit(EXIT_FAILURE); 772 } 773 break; 774 case 'v': 775 opts.verbose = true; 776 break; 777 case 'V': 778 version(argv[0]); 779 exit(0); 780 break; 781 case 'h': 782 usage(argv[0]); 783 exit(0); 784 break; 785 case '?': 786 error_report("Try `%s --help' for more information.", argv[0]); 787 exit(EXIT_FAILURE); 788 case QEMU_NBD_OPT_OBJECT: 789 user_creatable_process_cmdline(optarg); 790 break; 791 case QEMU_NBD_OPT_TLSCREDS: 792 tlscredsid = optarg; 793 break; 794 case QEMU_NBD_OPT_TLSHOSTNAME: 795 tlshostname = optarg; 796 break; 797 case QEMU_NBD_OPT_IMAGE_OPTS: 798 imageOpts = true; 799 break; 800 case 'T': 801 trace_opt_parse(optarg); 802 break; 803 case QEMU_NBD_OPT_TLSAUTHZ: 804 tlsauthz = optarg; 805 break; 806 case QEMU_NBD_OPT_FORK: 807 opts.fork_process = true; 808 break; 809 case 'L': 810 list = true; 811 break; 812 case QEMU_NBD_OPT_PID_FILE: 813 pid_file_name = optarg; 814 break; 815 case QEMU_NBD_OPT_SELINUX_LABEL: 816 selinux_label = optarg; 817 break; 818 } 819 } 820 821 if (list) { 822 if (argc != optind) { 823 error_report("List mode is incompatible with a file name"); 824 exit(EXIT_FAILURE); 825 } 826 if (export_name || export_description || dev_offset || 827 opts.device || disconnect || fmt || sn_id_or_name || bitmaps || 828 alloc_depth || seen_aio || seen_discard || seen_cache) { 829 error_report("List mode is incompatible with per-device settings"); 830 exit(EXIT_FAILURE); 831 } 832 if (opts.fork_process) { 833 error_report("List mode is incompatible with forking"); 834 exit(EXIT_FAILURE); 835 } 836 } else if ((argc - optind) != 1) { 837 error_report("Invalid number of arguments"); 838 error_printf("Try `%s --help' for more information.\n", argv[0]); 839 exit(EXIT_FAILURE); 840 } else if (!export_name) { 841 export_name = ""; 842 } 843 844 if (!trace_init_backends()) { 845 exit(1); 846 } 847 trace_init_file(); 848 qemu_set_log(LOG_TRACE, &error_fatal); 849 850 socket_activation = check_socket_activation(); 851 if (socket_activation == 0) { 852 if (!sockpath) { 853 setup_address_and_port(&bindto, &port); 854 } 855 } else { 856 /* Using socket activation - check user didn't use -p etc. */ 857 const char *err_msg = socket_activation_validate_opts(opts.device, 858 sockpath, 859 bindto, port, 860 selinux_label, 861 list); 862 if (err_msg != NULL) { 863 error_report("%s", err_msg); 864 exit(EXIT_FAILURE); 865 } 866 867 /* qemu-nbd can only listen on a single socket. */ 868 if (socket_activation > 1) { 869 error_report("qemu-nbd does not support socket activation with %s > 1", 870 "LISTEN_FDS"); 871 exit(EXIT_FAILURE); 872 } 873 } 874 875 if (tlscredsid) { 876 if (opts.device) { 877 error_report("TLS is not supported with a host device"); 878 exit(EXIT_FAILURE); 879 } 880 if (tlsauthz && list) { 881 error_report("TLS authorization is incompatible with export list"); 882 exit(EXIT_FAILURE); 883 } 884 if (tlshostname && !list) { 885 error_report("TLS hostname is only supported with export list"); 886 exit(EXIT_FAILURE); 887 } 888 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 889 if (local_err) { 890 error_reportf_err(local_err, "Failed to get TLS creds: "); 891 exit(EXIT_FAILURE); 892 } 893 } else { 894 if (tlsauthz) { 895 error_report("--tls-authz is not permitted without --tls-creds"); 896 exit(EXIT_FAILURE); 897 } 898 if (tlshostname) { 899 error_report("--tls-hostname is not permitted without --tls-creds"); 900 exit(EXIT_FAILURE); 901 } 902 } 903 904 if (selinux_label) { 905 #ifdef CONFIG_SELINUX 906 if (sockpath == NULL && opts.device == NULL) { 907 error_report("--selinux-label is not permitted without --socket"); 908 exit(EXIT_FAILURE); 909 } 910 #else 911 error_report("SELinux support not enabled in this binary"); 912 exit(EXIT_FAILURE); 913 #endif 914 } 915 916 if (list) { 917 opts.saddr = nbd_build_socket_address(sockpath, bindto, port); 918 return qemu_nbd_client_list(opts.saddr, tlscreds, 919 tlshostname ? tlshostname : bindto); 920 } 921 922 #if !HAVE_NBD_DEVICE 923 if (disconnect || opts.device) { 924 error_report("Kernel /dev/nbdN support not available"); 925 exit(EXIT_FAILURE); 926 } 927 #else /* HAVE_NBD_DEVICE */ 928 if (disconnect) { 929 int nbdfd = open(argv[optind], O_RDWR); 930 if (nbdfd < 0) { 931 error_report("Cannot open %s: %s", argv[optind], 932 strerror(errno)); 933 exit(EXIT_FAILURE); 934 } 935 nbd_disconnect(nbdfd); 936 937 close(nbdfd); 938 939 printf("%s disconnected\n", argv[optind]); 940 941 return 0; 942 } 943 #endif 944 945 if ((opts.device && !opts.verbose) || opts.fork_process) { 946 #ifndef WIN32 947 g_autoptr(GError) err = NULL; 948 int stderr_fd[2]; 949 pid_t pid; 950 951 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) { 952 error_report("Error setting up communication pipe: %s", 953 err->message); 954 exit(EXIT_FAILURE); 955 } 956 957 /* Now daemonize, but keep a communication channel open to 958 * print errors and exit with the proper status code. 959 */ 960 pid = fork(); 961 if (pid < 0) { 962 error_report("Failed to fork: %s", strerror(errno)); 963 exit(EXIT_FAILURE); 964 } else if (pid == 0) { 965 int saved_errno; 966 967 close(stderr_fd[0]); 968 969 /* Remember parent's stderr if we will be restoring it. */ 970 if (opts.verbose /* fork_process is set */) { 971 opts.old_stderr = dup(STDERR_FILENO); 972 if (opts.old_stderr < 0) { 973 error_report("Could not dup original stderr: %s", 974 strerror(errno)); 975 exit(EXIT_FAILURE); 976 } 977 } 978 979 ret = qemu_daemon(1, 0); 980 saved_errno = errno; /* dup2 will overwrite error below */ 981 982 /* Temporarily redirect stderr to the parent's pipe... */ 983 if (dup2(stderr_fd[1], STDERR_FILENO) < 0) { 984 char str[256]; 985 snprintf(str, sizeof(str), 986 "%s: Failed to link stderr to the pipe: %s\n", 987 g_get_prgname(), strerror(errno)); 988 /* 989 * We are unable to use error_report() here as we need to get 990 * stderr pointed to the parent's pipe. Write to that pipe 991 * manually. 992 */ 993 ret = write(stderr_fd[1], str, strlen(str)); 994 exit(EXIT_FAILURE); 995 } 996 997 if (ret < 0) { 998 error_report("Failed to daemonize: %s", strerror(saved_errno)); 999 exit(EXIT_FAILURE); 1000 } 1001 1002 /* ... close the descriptor we inherited and go on. */ 1003 close(stderr_fd[1]); 1004 } else { 1005 bool errors = false; 1006 char *buf; 1007 1008 /* In the parent. Print error messages from the child until 1009 * it closes the pipe. 1010 */ 1011 close(stderr_fd[1]); 1012 buf = g_malloc(1024); 1013 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 1014 errors = true; 1015 ret = qemu_write_full(STDERR_FILENO, buf, ret); 1016 if (ret < 0) { 1017 exit(EXIT_FAILURE); 1018 } 1019 } 1020 if (ret < 0) { 1021 error_report("Cannot read from daemon: %s", 1022 strerror(errno)); 1023 exit(EXIT_FAILURE); 1024 } 1025 1026 /* Usually the daemon should not print any message. 1027 * Exit with zero status in that case. 1028 */ 1029 exit(errors); 1030 } 1031 #else /* WIN32 */ 1032 error_report("Unable to fork into background on Windows hosts"); 1033 exit(EXIT_FAILURE); 1034 #endif /* WIN32 */ 1035 } 1036 1037 if (opts.device != NULL && sockpath == NULL) { 1038 sockpath = g_malloc(128); 1039 snprintf(sockpath, 128, SOCKET_PATH, basename(opts.device)); 1040 } 1041 1042 server = qio_net_listener_new(); 1043 if (socket_activation == 0) { 1044 int backlog; 1045 1046 if (persistent || shared == 0) { 1047 backlog = SOMAXCONN; 1048 } else { 1049 backlog = MIN(shared, SOMAXCONN); 1050 } 1051 #ifdef CONFIG_SELINUX 1052 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) { 1053 error_report("Cannot set SELinux socket create context to %s: %s", 1054 selinux_label, strerror(errno)); 1055 exit(EXIT_FAILURE); 1056 } 1057 #endif 1058 opts.saddr = nbd_build_socket_address(sockpath, bindto, port); 1059 if (qio_net_listener_open_sync(server, opts.saddr, backlog, 1060 &local_err) < 0) { 1061 object_unref(OBJECT(server)); 1062 error_report_err(local_err); 1063 exit(EXIT_FAILURE); 1064 } 1065 #ifdef CONFIG_SELINUX 1066 if (selinux_label && setsockcreatecon_raw(NULL) == -1) { 1067 error_report("Cannot clear SELinux socket create context: %s", 1068 strerror(errno)); 1069 exit(EXIT_FAILURE); 1070 } 1071 #endif 1072 } else { 1073 size_t i; 1074 /* See comment in check_socket_activation above. */ 1075 for (i = 0; i < socket_activation; i++) { 1076 QIOChannelSocket *sioc; 1077 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 1078 &local_err); 1079 if (sioc == NULL) { 1080 object_unref(OBJECT(server)); 1081 error_reportf_err(local_err, 1082 "Failed to use socket activation: "); 1083 exit(EXIT_FAILURE); 1084 } 1085 qio_net_listener_add(server, sioc); 1086 object_unref(OBJECT(sioc)); 1087 } 1088 } 1089 1090 qemu_init_main_loop(&error_fatal); 1091 bdrv_init(); 1092 atexit(qemu_nbd_shutdown); 1093 1094 opts.srcpath = argv[optind]; 1095 if (imageOpts) { 1096 QemuOpts *o; 1097 if (fmt) { 1098 error_report("--image-opts and -f are mutually exclusive"); 1099 exit(EXIT_FAILURE); 1100 } 1101 o = qemu_opts_parse_noisily(&file_opts, opts.srcpath, true); 1102 if (!o) { 1103 qemu_opts_reset(&file_opts); 1104 exit(EXIT_FAILURE); 1105 } 1106 options = qemu_opts_to_qdict(o, NULL); 1107 qemu_opts_reset(&file_opts); 1108 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1109 } else { 1110 if (fmt) { 1111 options = qdict_new(); 1112 qdict_put_str(options, "driver", fmt); 1113 } 1114 blk = blk_new_open(opts.srcpath, NULL, options, flags, &local_err); 1115 } 1116 1117 if (!blk) { 1118 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1119 argv[optind]); 1120 exit(EXIT_FAILURE); 1121 } 1122 bs = blk_bs(blk); 1123 1124 if (dev_offset) { 1125 QDict *raw_opts = qdict_new(); 1126 qdict_put_str(raw_opts, "driver", "raw"); 1127 qdict_put_str(raw_opts, "file", bs->node_name); 1128 qdict_put_int(raw_opts, "offset", dev_offset); 1129 1130 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1131 1132 blk_remove_bs(blk); 1133 blk_insert_bs(blk, bs, &error_fatal); 1134 bdrv_unref(bs); 1135 } 1136 1137 blk_set_enable_write_cache(blk, !writethrough); 1138 1139 if (sn_opts) { 1140 ret = bdrv_snapshot_load_tmp(bs, 1141 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1142 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1143 &local_err); 1144 } else if (sn_id_or_name) { 1145 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1146 &local_err); 1147 } 1148 if (ret < 0) { 1149 error_reportf_err(local_err, "Failed to load snapshot: "); 1150 exit(EXIT_FAILURE); 1151 } 1152 1153 bs->detect_zeroes = detect_zeroes; 1154 1155 nbd_server_is_qemu_nbd(shared); 1156 1157 export_opts = g_new(BlockExportOptions, 1); 1158 *export_opts = (BlockExportOptions) { 1159 .type = BLOCK_EXPORT_TYPE_NBD, 1160 .id = g_strdup("qemu-nbd-export"), 1161 .node_name = g_strdup(bdrv_get_node_name(bs)), 1162 .has_writethrough = true, 1163 .writethrough = writethrough, 1164 .has_writable = true, 1165 .writable = !readonly, 1166 .u.nbd = { 1167 .name = g_strdup(export_name), 1168 .description = g_strdup(export_description), 1169 .has_bitmaps = !!bitmaps, 1170 .bitmaps = bitmaps, 1171 .has_allocation_depth = alloc_depth, 1172 .allocation_depth = alloc_depth, 1173 }, 1174 }; 1175 blk_exp_add(export_opts, &error_fatal); 1176 qapi_free_BlockExportOptions(export_opts); 1177 1178 if (opts.device) { 1179 #if HAVE_NBD_DEVICE 1180 ret = pthread_create(&client_thread, NULL, nbd_client_thread, &opts); 1181 if (ret != 0) { 1182 error_report("Failed to create client thread: %s", strerror(ret)); 1183 exit(EXIT_FAILURE); 1184 } 1185 #endif 1186 } else { 1187 /* Shut up GCC warnings. */ 1188 memset(&client_thread, 0, sizeof(client_thread)); 1189 } 1190 1191 nbd_update_server_watch(); 1192 1193 if (pid_file_name) { 1194 qemu_write_pidfile(pid_file_name, &error_fatal); 1195 } 1196 1197 /* now when the initialization is (almost) complete, chdir("/") 1198 * to free any busy filesystems */ 1199 if (chdir("/") < 0) { 1200 error_report("Could not chdir to root directory: %s", 1201 strerror(errno)); 1202 exit(EXIT_FAILURE); 1203 } 1204 1205 if (opts.fork_process) { 1206 nbd_client_release_pipe(opts.old_stderr); 1207 } 1208 1209 state = RUNNING; 1210 do { 1211 main_loop_wait(false); 1212 if (state == TERMINATE) { 1213 blk_exp_close_all(); 1214 state = TERMINATED; 1215 } 1216 } while (state != TERMINATED); 1217 1218 blk_unref(blk); 1219 if (sockpath) { 1220 unlink(sockpath); 1221 } 1222 1223 qemu_opts_del(sn_opts); 1224 1225 if (opts.device) { 1226 void *result; 1227 pthread_join(client_thread, &result); 1228 ret = (intptr_t)result; 1229 exit(ret); 1230 } else { 1231 exit(EXIT_SUCCESS); 1232 } 1233 } 1234