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 "qapi/error.h" 25 #include "qemu-common.h" 26 #include "qemu/cutils.h" 27 #include "sysemu/block-backend.h" 28 #include "block/block_int.h" 29 #include "block/nbd.h" 30 #include "qemu/main-loop.h" 31 #include "qemu/error-report.h" 32 #include "qemu/config-file.h" 33 #include "qemu/bswap.h" 34 #include "qemu/log.h" 35 #include "qemu/systemd.h" 36 #include "block/snapshot.h" 37 #include "qapi/qmp/qstring.h" 38 #include "qom/object_interfaces.h" 39 #include "io/channel-socket.h" 40 #include "crypto/init.h" 41 #include "trace/control.h" 42 #include "qemu-version.h" 43 44 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 45 #define QEMU_NBD_OPT_CACHE 256 46 #define QEMU_NBD_OPT_AIO 257 47 #define QEMU_NBD_OPT_DISCARD 258 48 #define QEMU_NBD_OPT_DETECT_ZEROES 259 49 #define QEMU_NBD_OPT_OBJECT 260 50 #define QEMU_NBD_OPT_TLSCREDS 261 51 #define QEMU_NBD_OPT_IMAGE_OPTS 262 52 #define QEMU_NBD_OPT_FORK 263 53 54 #define MBR_SIZE 512 55 56 static NBDExport *exp; 57 static bool newproto; 58 static int verbose; 59 static char *srcpath; 60 static SocketAddress *saddr; 61 static int persistent = 0; 62 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 63 static int shared = 1; 64 static int nb_fds; 65 static QIOChannelSocket *server_ioc; 66 static int server_watch = -1; 67 static QCryptoTLSCreds *tlscreds; 68 69 static void usage(const char *name) 70 { 71 (printf) ( 72 "Usage: %s [OPTIONS] FILE\n" 73 "QEMU Disk Network Block Device Server\n" 74 "\n" 75 " -h, --help display this help and exit\n" 76 " -V, --version output version information and exit\n" 77 "\n" 78 "Connection properties:\n" 79 " -p, --port=PORT port to listen on (default `%d')\n" 80 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 81 " -k, --socket=PATH path to the unix socket\n" 82 " (default '"SOCKET_PATH"')\n" 83 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 84 " -t, --persistent don't exit on the last connection\n" 85 " -v, --verbose display extra debugging information\n" 86 " -x, --export-name=NAME expose export by name\n" 87 " -D, --description=TEXT with -x, also export a human-readable description\n" 88 "\n" 89 "Exposing part of the image:\n" 90 " -o, --offset=OFFSET offset into the image\n" 91 " -P, --partition=NUM only expose partition NUM\n" 92 "\n" 93 "General purpose options:\n" 94 " --object type,id=ID,... define an object such as 'secret' for providing\n" 95 " passwords and/or encryption keys\n" 96 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 97 " specify tracing options\n" 98 " --fork fork off the server process and exit the parent\n" 99 " once the server is running\n" 100 #ifdef __linux__ 101 "Kernel NBD client support:\n" 102 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 103 " -d, --disconnect disconnect the specified device\n" 104 "\n" 105 #endif 106 "\n" 107 "Block device options:\n" 108 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 109 " -r, --read-only export read-only\n" 110 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 111 " file with backing_file=FILE, redirect the write to\n" 112 " the temporary one\n" 113 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 114 " load an internal snapshot inside FILE and export it\n" 115 " as an read-only device, SNAPSHOT_PARAM format is\n" 116 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 117 " '[ID_OR_NAME]'\n" 118 " -n, --nocache disable host cache\n" 119 " --cache=MODE set cache mode (none, writeback, ...)\n" 120 " --aio=MODE set AIO mode (native or threads)\n" 121 " --discard=MODE set discard mode (ignore, unmap)\n" 122 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 123 " --image-opts treat FILE as a full set of image options\n" 124 "\n" 125 QEMU_HELP_BOTTOM "\n" 126 , name, NBD_DEFAULT_PORT, "DEVICE"); 127 } 128 129 static void version(const char *name) 130 { 131 printf( 132 "%s " QEMU_VERSION QEMU_PKGVERSION "\n" 133 "Written by Anthony Liguori.\n" 134 "\n" 135 QEMU_COPYRIGHT "\n" 136 "This is free software; see the source for copying conditions. There is NO\n" 137 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 138 , name); 139 } 140 141 struct partition_record 142 { 143 uint8_t bootable; 144 uint8_t start_head; 145 uint32_t start_cylinder; 146 uint8_t start_sector; 147 uint8_t system; 148 uint8_t end_head; 149 uint8_t end_cylinder; 150 uint8_t end_sector; 151 uint32_t start_sector_abs; 152 uint32_t nb_sectors_abs; 153 }; 154 155 static void read_partition(uint8_t *p, struct partition_record *r) 156 { 157 r->bootable = p[0]; 158 r->start_head = p[1]; 159 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 160 r->start_sector = p[2] & 0x3f; 161 r->system = p[4]; 162 r->end_head = p[5]; 163 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 164 r->end_sector = p[6] & 0x3f; 165 166 r->start_sector_abs = ldl_le_p(p + 8); 167 r->nb_sectors_abs = ldl_le_p(p + 12); 168 } 169 170 static int find_partition(BlockBackend *blk, int partition, 171 off_t *offset, off_t *size) 172 { 173 struct partition_record mbr[4]; 174 uint8_t data[MBR_SIZE]; 175 int i; 176 int ext_partnum = 4; 177 int ret; 178 179 ret = blk_pread(blk, 0, data, sizeof(data)); 180 if (ret < 0) { 181 error_report("error while reading: %s", strerror(-ret)); 182 exit(EXIT_FAILURE); 183 } 184 185 if (data[510] != 0x55 || data[511] != 0xaa) { 186 return -EINVAL; 187 } 188 189 for (i = 0; i < 4; i++) { 190 read_partition(&data[446 + 16 * i], &mbr[i]); 191 192 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 193 continue; 194 } 195 196 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 197 struct partition_record ext[4]; 198 uint8_t data1[MBR_SIZE]; 199 int j; 200 201 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 202 data1, sizeof(data1)); 203 if (ret < 0) { 204 error_report("error while reading: %s", strerror(-ret)); 205 exit(EXIT_FAILURE); 206 } 207 208 for (j = 0; j < 4; j++) { 209 read_partition(&data1[446 + 16 * j], &ext[j]); 210 if (!ext[j].system || !ext[j].nb_sectors_abs) { 211 continue; 212 } 213 214 if ((ext_partnum + j + 1) == partition) { 215 *offset = (uint64_t)ext[j].start_sector_abs << 9; 216 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 217 return 0; 218 } 219 } 220 ext_partnum += 4; 221 } else if ((i + 1) == partition) { 222 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 223 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 224 return 0; 225 } 226 } 227 228 return -ENOENT; 229 } 230 231 static void termsig_handler(int signum) 232 { 233 atomic_cmpxchg(&state, RUNNING, TERMINATE); 234 qemu_notify_event(); 235 } 236 237 238 static void *show_parts(void *arg) 239 { 240 char *device = arg; 241 int nbd; 242 243 /* linux just needs an open() to trigger 244 * the partition table update 245 * but remember to load the module with max_part != 0 : 246 * modprobe nbd max_part=63 247 */ 248 nbd = open(device, O_RDWR); 249 if (nbd >= 0) { 250 close(nbd); 251 } 252 return NULL; 253 } 254 255 static void *nbd_client_thread(void *arg) 256 { 257 char *device = arg; 258 NBDExportInfo info = { .request_sizes = false, }; 259 QIOChannelSocket *sioc; 260 int fd; 261 int ret; 262 pthread_t show_parts_thread; 263 Error *local_error = NULL; 264 265 sioc = qio_channel_socket_new(); 266 if (qio_channel_socket_connect_sync(sioc, 267 saddr, 268 &local_error) < 0) { 269 error_report_err(local_error); 270 goto out; 271 } 272 273 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, 274 NULL, NULL, NULL, &info, &local_error); 275 if (ret < 0) { 276 if (local_error) { 277 error_report_err(local_error); 278 } 279 goto out_socket; 280 } 281 282 fd = open(device, O_RDWR); 283 if (fd < 0) { 284 /* Linux-only, we can use %m in printf. */ 285 error_report("Failed to open %s: %m", device); 286 goto out_socket; 287 } 288 289 ret = nbd_init(fd, sioc, &info, &local_error); 290 if (ret < 0) { 291 error_report_err(local_error); 292 goto out_fd; 293 } 294 295 /* update partition table */ 296 pthread_create(&show_parts_thread, NULL, show_parts, device); 297 298 if (verbose) { 299 fprintf(stderr, "NBD device %s is now connected to %s\n", 300 device, srcpath); 301 } else { 302 /* Close stderr so that the qemu-nbd process exits. */ 303 dup2(STDOUT_FILENO, STDERR_FILENO); 304 } 305 306 ret = nbd_client(fd); 307 if (ret) { 308 goto out_fd; 309 } 310 close(fd); 311 object_unref(OBJECT(sioc)); 312 kill(getpid(), SIGTERM); 313 return (void *) EXIT_SUCCESS; 314 315 out_fd: 316 close(fd); 317 out_socket: 318 object_unref(OBJECT(sioc)); 319 out: 320 kill(getpid(), SIGTERM); 321 return (void *) EXIT_FAILURE; 322 } 323 324 static int nbd_can_accept(void) 325 { 326 return state == RUNNING && nb_fds < shared; 327 } 328 329 static void nbd_export_closed(NBDExport *exp) 330 { 331 assert(state == TERMINATING); 332 state = TERMINATED; 333 } 334 335 static void nbd_update_server_watch(void); 336 337 static void nbd_client_closed(NBDClient *client, bool negotiated) 338 { 339 nb_fds--; 340 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 341 state = TERMINATE; 342 } 343 nbd_update_server_watch(); 344 nbd_client_put(client); 345 } 346 347 static gboolean nbd_accept(QIOChannel *ioc, GIOCondition cond, gpointer opaque) 348 { 349 QIOChannelSocket *cioc; 350 351 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc), 352 NULL); 353 if (!cioc) { 354 return TRUE; 355 } 356 357 if (state >= TERMINATE) { 358 object_unref(OBJECT(cioc)); 359 return TRUE; 360 } 361 362 nb_fds++; 363 nbd_update_server_watch(); 364 nbd_client_new(newproto ? NULL : exp, cioc, 365 tlscreds, NULL, nbd_client_closed); 366 object_unref(OBJECT(cioc)); 367 368 return TRUE; 369 } 370 371 static void nbd_update_server_watch(void) 372 { 373 if (nbd_can_accept()) { 374 if (server_watch == -1) { 375 server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc), 376 G_IO_IN, 377 nbd_accept, 378 NULL, NULL); 379 } 380 } else { 381 if (server_watch != -1) { 382 g_source_remove(server_watch); 383 server_watch = -1; 384 } 385 } 386 } 387 388 389 static SocketAddress *nbd_build_socket_address(const char *sockpath, 390 const char *bindto, 391 const char *port) 392 { 393 SocketAddress *saddr; 394 395 saddr = g_new0(SocketAddress, 1); 396 if (sockpath) { 397 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 398 saddr->u.q_unix.path = g_strdup(sockpath); 399 } else { 400 InetSocketAddress *inet; 401 saddr->type = SOCKET_ADDRESS_TYPE_INET; 402 inet = &saddr->u.inet; 403 inet->host = g_strdup(bindto); 404 if (port) { 405 inet->port = g_strdup(port); 406 } else { 407 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 408 } 409 } 410 411 return saddr; 412 } 413 414 415 static QemuOptsList file_opts = { 416 .name = "file", 417 .implied_opt_name = "file", 418 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 419 .desc = { 420 /* no elements => accept any params */ 421 { /* end of list */ } 422 }, 423 }; 424 425 static QemuOptsList qemu_object_opts = { 426 .name = "object", 427 .implied_opt_name = "qom-type", 428 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 429 .desc = { 430 { } 431 }, 432 }; 433 434 435 436 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, 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 (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 457 error_setg(errp, 458 "Expecting TLS credentials with a server endpoint"); 459 return NULL; 460 } 461 object_ref(obj); 462 return creds; 463 } 464 465 static void setup_address_and_port(const char **address, const char **port) 466 { 467 if (*address == NULL) { 468 *address = "0.0.0.0"; 469 } 470 471 if (*port == NULL) { 472 *port = stringify(NBD_DEFAULT_PORT); 473 } 474 } 475 476 /* 477 * Check socket parameters compatibility when socket activation is used. 478 */ 479 static const char *socket_activation_validate_opts(const char *device, 480 const char *sockpath, 481 const char *address, 482 const char *port) 483 { 484 if (device != NULL) { 485 return "NBD device can't be set when using socket activation"; 486 } 487 488 if (sockpath != NULL) { 489 return "Unix socket can't be set when using socket activation"; 490 } 491 492 if (address != NULL) { 493 return "The interface can't be set when using socket activation"; 494 } 495 496 if (port != NULL) { 497 return "TCP port number can't be set when using socket activation"; 498 } 499 500 return NULL; 501 } 502 503 int main(int argc, char **argv) 504 { 505 BlockBackend *blk; 506 BlockDriverState *bs; 507 off_t dev_offset = 0; 508 uint16_t nbdflags = 0; 509 bool disconnect = false; 510 const char *bindto = NULL; 511 const char *port = NULL; 512 char *sockpath = NULL; 513 char *device = NULL; 514 off_t fd_size; 515 QemuOpts *sn_opts = NULL; 516 const char *sn_id_or_name = NULL; 517 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 518 struct option lopt[] = { 519 { "help", no_argument, NULL, 'h' }, 520 { "version", no_argument, NULL, 'V' }, 521 { "bind", required_argument, NULL, 'b' }, 522 { "port", required_argument, NULL, 'p' }, 523 { "socket", required_argument, NULL, 'k' }, 524 { "offset", required_argument, NULL, 'o' }, 525 { "read-only", no_argument, NULL, 'r' }, 526 { "partition", required_argument, NULL, 'P' }, 527 { "connect", required_argument, NULL, 'c' }, 528 { "disconnect", no_argument, NULL, 'd' }, 529 { "snapshot", no_argument, NULL, 's' }, 530 { "load-snapshot", required_argument, NULL, 'l' }, 531 { "nocache", no_argument, NULL, 'n' }, 532 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 533 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 534 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 535 { "detect-zeroes", required_argument, NULL, 536 QEMU_NBD_OPT_DETECT_ZEROES }, 537 { "shared", required_argument, NULL, 'e' }, 538 { "format", required_argument, NULL, 'f' }, 539 { "persistent", no_argument, NULL, 't' }, 540 { "verbose", no_argument, NULL, 'v' }, 541 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 542 { "export-name", required_argument, NULL, 'x' }, 543 { "description", required_argument, NULL, 'D' }, 544 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 545 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 546 { "trace", required_argument, NULL, 'T' }, 547 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 548 { NULL, 0, NULL, 0 } 549 }; 550 int ch; 551 int opt_ind = 0; 552 char *end; 553 int flags = BDRV_O_RDWR; 554 int partition = -1; 555 int ret = 0; 556 bool seen_cache = false; 557 bool seen_discard = false; 558 bool seen_aio = false; 559 pthread_t client_thread; 560 const char *fmt = NULL; 561 Error *local_err = NULL; 562 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 563 QDict *options = NULL; 564 const char *export_name = NULL; 565 const char *export_description = NULL; 566 const char *tlscredsid = NULL; 567 bool imageOpts = false; 568 bool writethrough = true; 569 char *trace_file = NULL; 570 bool fork_process = false; 571 int old_stderr = -1; 572 unsigned socket_activation; 573 574 /* The client thread uses SIGTERM to interrupt the server. A signal 575 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 576 */ 577 struct sigaction sa_sigterm; 578 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 579 sa_sigterm.sa_handler = termsig_handler; 580 sigaction(SIGTERM, &sa_sigterm, NULL); 581 582 #ifdef CONFIG_POSIX 583 signal(SIGPIPE, SIG_IGN); 584 #endif 585 586 module_call_init(MODULE_INIT_TRACE); 587 qcrypto_init(&error_fatal); 588 589 module_call_init(MODULE_INIT_QOM); 590 qemu_add_opts(&qemu_object_opts); 591 qemu_add_opts(&qemu_trace_opts); 592 qemu_init_exec_dir(argv[0]); 593 594 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 595 switch (ch) { 596 case 's': 597 flags |= BDRV_O_SNAPSHOT; 598 break; 599 case 'n': 600 optarg = (char *) "none"; 601 /* fallthrough */ 602 case QEMU_NBD_OPT_CACHE: 603 if (seen_cache) { 604 error_report("-n and --cache can only be specified once"); 605 exit(EXIT_FAILURE); 606 } 607 seen_cache = true; 608 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 609 error_report("Invalid cache mode `%s'", optarg); 610 exit(EXIT_FAILURE); 611 } 612 break; 613 case QEMU_NBD_OPT_AIO: 614 if (seen_aio) { 615 error_report("--aio can only be specified once"); 616 exit(EXIT_FAILURE); 617 } 618 seen_aio = true; 619 if (!strcmp(optarg, "native")) { 620 flags |= BDRV_O_NATIVE_AIO; 621 } else if (!strcmp(optarg, "threads")) { 622 /* this is the default */ 623 } else { 624 error_report("invalid aio mode `%s'", optarg); 625 exit(EXIT_FAILURE); 626 } 627 break; 628 case QEMU_NBD_OPT_DISCARD: 629 if (seen_discard) { 630 error_report("--discard can only be specified once"); 631 exit(EXIT_FAILURE); 632 } 633 seen_discard = true; 634 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 635 error_report("Invalid discard mode `%s'", optarg); 636 exit(EXIT_FAILURE); 637 } 638 break; 639 case QEMU_NBD_OPT_DETECT_ZEROES: 640 detect_zeroes = 641 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 642 optarg, 643 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 644 &local_err); 645 if (local_err) { 646 error_reportf_err(local_err, 647 "Failed to parse detect_zeroes mode: "); 648 exit(EXIT_FAILURE); 649 } 650 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 651 !(flags & BDRV_O_UNMAP)) { 652 error_report("setting detect-zeroes to unmap is not allowed " 653 "without setting discard operation to unmap"); 654 exit(EXIT_FAILURE); 655 } 656 break; 657 case 'b': 658 bindto = optarg; 659 break; 660 case 'p': 661 port = optarg; 662 break; 663 case 'o': 664 dev_offset = strtoll (optarg, &end, 0); 665 if (*end) { 666 error_report("Invalid offset `%s'", optarg); 667 exit(EXIT_FAILURE); 668 } 669 if (dev_offset < 0) { 670 error_report("Offset must be positive `%s'", optarg); 671 exit(EXIT_FAILURE); 672 } 673 break; 674 case 'l': 675 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 676 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 677 optarg, false); 678 if (!sn_opts) { 679 error_report("Failed in parsing snapshot param `%s'", 680 optarg); 681 exit(EXIT_FAILURE); 682 } 683 } else { 684 sn_id_or_name = optarg; 685 } 686 /* fall through */ 687 case 'r': 688 nbdflags |= NBD_FLAG_READ_ONLY; 689 flags &= ~BDRV_O_RDWR; 690 break; 691 case 'P': 692 partition = strtol(optarg, &end, 0); 693 if (*end) { 694 error_report("Invalid partition `%s'", optarg); 695 exit(EXIT_FAILURE); 696 } 697 if (partition < 1 || partition > 8) { 698 error_report("Invalid partition %d", partition); 699 exit(EXIT_FAILURE); 700 } 701 break; 702 case 'k': 703 sockpath = optarg; 704 if (sockpath[0] != '/') { 705 error_report("socket path must be absolute"); 706 exit(EXIT_FAILURE); 707 } 708 break; 709 case 'd': 710 disconnect = true; 711 break; 712 case 'c': 713 device = optarg; 714 break; 715 case 'e': 716 shared = strtol(optarg, &end, 0); 717 if (*end) { 718 error_report("Invalid shared device number '%s'", optarg); 719 exit(EXIT_FAILURE); 720 } 721 if (shared < 1) { 722 error_report("Shared device number must be greater than 0"); 723 exit(EXIT_FAILURE); 724 } 725 break; 726 case 'f': 727 fmt = optarg; 728 break; 729 case 't': 730 persistent = 1; 731 break; 732 case 'x': 733 export_name = optarg; 734 break; 735 case 'D': 736 export_description = optarg; 737 break; 738 case 'v': 739 verbose = 1; 740 break; 741 case 'V': 742 version(argv[0]); 743 exit(0); 744 break; 745 case 'h': 746 usage(argv[0]); 747 exit(0); 748 break; 749 case '?': 750 error_report("Try `%s --help' for more information.", argv[0]); 751 exit(EXIT_FAILURE); 752 case QEMU_NBD_OPT_OBJECT: { 753 QemuOpts *opts; 754 opts = qemu_opts_parse_noisily(&qemu_object_opts, 755 optarg, true); 756 if (!opts) { 757 exit(EXIT_FAILURE); 758 } 759 } break; 760 case QEMU_NBD_OPT_TLSCREDS: 761 tlscredsid = optarg; 762 break; 763 case QEMU_NBD_OPT_IMAGE_OPTS: 764 imageOpts = true; 765 break; 766 case 'T': 767 g_free(trace_file); 768 trace_file = trace_opt_parse(optarg); 769 break; 770 case QEMU_NBD_OPT_FORK: 771 fork_process = true; 772 break; 773 } 774 } 775 776 if ((argc - optind) != 1) { 777 error_report("Invalid number of arguments"); 778 error_printf("Try `%s --help' for more information.\n", argv[0]); 779 exit(EXIT_FAILURE); 780 } 781 782 if (qemu_opts_foreach(&qemu_object_opts, 783 user_creatable_add_opts_foreach, 784 NULL, NULL)) { 785 exit(EXIT_FAILURE); 786 } 787 788 if (!trace_init_backends()) { 789 exit(1); 790 } 791 trace_init_file(trace_file); 792 qemu_set_log(LOG_TRACE); 793 794 socket_activation = check_socket_activation(); 795 if (socket_activation == 0) { 796 setup_address_and_port(&bindto, &port); 797 } else { 798 /* Using socket activation - check user didn't use -p etc. */ 799 const char *err_msg = socket_activation_validate_opts(device, sockpath, 800 bindto, port); 801 if (err_msg != NULL) { 802 error_report("%s", err_msg); 803 exit(EXIT_FAILURE); 804 } 805 806 /* qemu-nbd can only listen on a single socket. */ 807 if (socket_activation > 1) { 808 error_report("qemu-nbd does not support socket activation with %s > 1", 809 "LISTEN_FDS"); 810 exit(EXIT_FAILURE); 811 } 812 } 813 814 if (tlscredsid) { 815 if (sockpath) { 816 error_report("TLS is only supported with IPv4/IPv6"); 817 exit(EXIT_FAILURE); 818 } 819 if (device) { 820 error_report("TLS is not supported with a host device"); 821 exit(EXIT_FAILURE); 822 } 823 if (!export_name) { 824 /* Set the default NBD protocol export name, since 825 * we *must* use new style protocol for TLS */ 826 export_name = ""; 827 } 828 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 829 if (local_err) { 830 error_report("Failed to get TLS creds %s", 831 error_get_pretty(local_err)); 832 exit(EXIT_FAILURE); 833 } 834 } 835 836 if (disconnect) { 837 int nbdfd = open(argv[optind], O_RDWR); 838 if (nbdfd < 0) { 839 error_report("Cannot open %s: %s", argv[optind], 840 strerror(errno)); 841 exit(EXIT_FAILURE); 842 } 843 nbd_disconnect(nbdfd); 844 845 close(nbdfd); 846 847 printf("%s disconnected\n", argv[optind]); 848 849 return 0; 850 } 851 852 if ((device && !verbose) || fork_process) { 853 int stderr_fd[2]; 854 pid_t pid; 855 int ret; 856 857 if (qemu_pipe(stderr_fd) < 0) { 858 error_report("Error setting up communication pipe: %s", 859 strerror(errno)); 860 exit(EXIT_FAILURE); 861 } 862 863 /* Now daemonize, but keep a communication channel open to 864 * print errors and exit with the proper status code. 865 */ 866 pid = fork(); 867 if (pid < 0) { 868 error_report("Failed to fork: %s", strerror(errno)); 869 exit(EXIT_FAILURE); 870 } else if (pid == 0) { 871 close(stderr_fd[0]); 872 ret = qemu_daemon(1, 0); 873 874 /* Temporarily redirect stderr to the parent's pipe... */ 875 old_stderr = dup(STDERR_FILENO); 876 dup2(stderr_fd[1], STDERR_FILENO); 877 if (ret < 0) { 878 error_report("Failed to daemonize: %s", strerror(errno)); 879 exit(EXIT_FAILURE); 880 } 881 882 /* ... close the descriptor we inherited and go on. */ 883 close(stderr_fd[1]); 884 } else { 885 bool errors = false; 886 char *buf; 887 888 /* In the parent. Print error messages from the child until 889 * it closes the pipe. 890 */ 891 close(stderr_fd[1]); 892 buf = g_malloc(1024); 893 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 894 errors = true; 895 ret = qemu_write_full(STDERR_FILENO, buf, ret); 896 if (ret < 0) { 897 exit(EXIT_FAILURE); 898 } 899 } 900 if (ret < 0) { 901 error_report("Cannot read from daemon: %s", 902 strerror(errno)); 903 exit(EXIT_FAILURE); 904 } 905 906 /* Usually the daemon should not print any message. 907 * Exit with zero status in that case. 908 */ 909 exit(errors); 910 } 911 } 912 913 if (device != NULL && sockpath == NULL) { 914 sockpath = g_malloc(128); 915 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 916 } 917 918 if (socket_activation == 0) { 919 server_ioc = qio_channel_socket_new(); 920 saddr = nbd_build_socket_address(sockpath, bindto, port); 921 if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) { 922 object_unref(OBJECT(server_ioc)); 923 error_report_err(local_err); 924 return 1; 925 } 926 } else { 927 /* See comment in check_socket_activation above. */ 928 assert(socket_activation == 1); 929 server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD, 930 &local_err); 931 if (server_ioc == NULL) { 932 error_report("Failed to use socket activation: %s", 933 error_get_pretty(local_err)); 934 exit(EXIT_FAILURE); 935 } 936 } 937 938 if (qemu_init_main_loop(&local_err)) { 939 error_report_err(local_err); 940 exit(EXIT_FAILURE); 941 } 942 bdrv_init(); 943 atexit(bdrv_close_all); 944 945 srcpath = argv[optind]; 946 if (imageOpts) { 947 QemuOpts *opts; 948 if (fmt) { 949 error_report("--image-opts and -f are mutually exclusive"); 950 exit(EXIT_FAILURE); 951 } 952 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 953 if (!opts) { 954 qemu_opts_reset(&file_opts); 955 exit(EXIT_FAILURE); 956 } 957 options = qemu_opts_to_qdict(opts, NULL); 958 qemu_opts_reset(&file_opts); 959 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 960 } else { 961 if (fmt) { 962 options = qdict_new(); 963 qdict_put_str(options, "driver", fmt); 964 } 965 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 966 } 967 968 if (!blk) { 969 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 970 argv[optind]); 971 exit(EXIT_FAILURE); 972 } 973 bs = blk_bs(blk); 974 975 blk_set_enable_write_cache(blk, !writethrough); 976 977 if (sn_opts) { 978 ret = bdrv_snapshot_load_tmp(bs, 979 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 980 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 981 &local_err); 982 } else if (sn_id_or_name) { 983 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 984 &local_err); 985 } 986 if (ret < 0) { 987 error_reportf_err(local_err, "Failed to load snapshot: "); 988 exit(EXIT_FAILURE); 989 } 990 991 bs->detect_zeroes = detect_zeroes; 992 fd_size = blk_getlength(blk); 993 if (fd_size < 0) { 994 error_report("Failed to determine the image length: %s", 995 strerror(-fd_size)); 996 exit(EXIT_FAILURE); 997 } 998 999 if (dev_offset >= fd_size) { 1000 error_report("Offset (%lld) has to be smaller than the image size " 1001 "(%lld)", 1002 (long long int)dev_offset, (long long int)fd_size); 1003 exit(EXIT_FAILURE); 1004 } 1005 fd_size -= dev_offset; 1006 1007 if (partition != -1) { 1008 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1009 if (ret < 0) { 1010 error_report("Could not find partition %d: %s", partition, 1011 strerror(-ret)); 1012 exit(EXIT_FAILURE); 1013 } 1014 } 1015 1016 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1017 writethrough, NULL, &local_err); 1018 if (!exp) { 1019 error_report_err(local_err); 1020 exit(EXIT_FAILURE); 1021 } 1022 if (export_name) { 1023 nbd_export_set_name(exp, export_name); 1024 nbd_export_set_description(exp, export_description); 1025 newproto = true; 1026 } else if (export_description) { 1027 error_report("Export description requires an export name"); 1028 exit(EXIT_FAILURE); 1029 } 1030 1031 if (device) { 1032 int ret; 1033 1034 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1035 if (ret != 0) { 1036 error_report("Failed to create client thread: %s", strerror(ret)); 1037 exit(EXIT_FAILURE); 1038 } 1039 } else { 1040 /* Shut up GCC warnings. */ 1041 memset(&client_thread, 0, sizeof(client_thread)); 1042 } 1043 1044 nbd_update_server_watch(); 1045 1046 /* now when the initialization is (almost) complete, chdir("/") 1047 * to free any busy filesystems */ 1048 if (chdir("/") < 0) { 1049 error_report("Could not chdir to root directory: %s", 1050 strerror(errno)); 1051 exit(EXIT_FAILURE); 1052 } 1053 1054 if (fork_process) { 1055 dup2(old_stderr, STDERR_FILENO); 1056 close(old_stderr); 1057 } 1058 1059 state = RUNNING; 1060 do { 1061 main_loop_wait(false); 1062 if (state == TERMINATE) { 1063 state = TERMINATING; 1064 nbd_export_close(exp); 1065 nbd_export_put(exp); 1066 exp = NULL; 1067 } 1068 } while (state != TERMINATED); 1069 1070 blk_unref(blk); 1071 if (sockpath) { 1072 unlink(sockpath); 1073 } 1074 1075 qemu_opts_del(sn_opts); 1076 1077 if (device) { 1078 void *ret; 1079 pthread_join(client_thread, &ret); 1080 exit(ret != NULL); 1081 } else { 1082 exit(EXIT_SUCCESS); 1083 } 1084 } 1085