qga/main.c

   1 /*
   2  * QEMU Guest Agent
   3  *
   4  * Copyright IBM Corp. 2011
   5  *
   6  * Authors:
   7  *  Adam Litke        <aglitke@linux.vnet.ibm.com>
   8  *  Michael Roth      <mdroth@linux.vnet.ibm.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  11  * See the COPYING file in the top-level directory.
  12  */
  13 #include <stdlib.h>
  14 #include <stdio.h>
  15 #include <stdbool.h>
  16 #include <glib.h>
  17 #include <getopt.h>
  18 #ifndef _WIN32
  19 #include <syslog.h>
  20 #include <sys/wait.h>
  21 #include <sys/stat.h>
  22 #endif
  23 #include "qapi/qmp/json-streamer.h"
  24 #include "qapi/qmp/json-parser.h"
  25 #include "qapi/qmp/qint.h"
  26 #include "qapi/qmp/qjson.h"
  27 #include "qga/guest-agent-core.h"
  28 #include "qemu/module.h"
  29 #include "signal.h"
  30 #include "qapi/qmp/qerror.h"
  31 #include "qapi/qmp/dispatch.h"
  32 #include "qga/channel.h"
  33 #ifdef _WIN32
  34 #include "qga/service-win32.h"
  35 #include <windows.h>
  36 #endif
  37 #ifdef __linux__
  38 #include <linux/fs.h>
  39 #ifdef FIFREEZE
  40 #define CONFIG_FSFREEZE
  41 #endif
  42 #endif
  43
  44 #ifndef _WIN32
  45 #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
  46 #else
  47 #define QGA_VIRTIO_PATH_DEFAULT "\\\\.\\Global\\org.qemu.guest_agent.0"
  48 #endif
  49 #define QGA_STATEDIR_DEFAULT CONFIG_QEMU_LOCALSTATEDIR "/run"
  50 #define QGA_PIDFILE_DEFAULT QGA_STATEDIR_DEFAULT "/qemu-ga.pid"
  51 #ifdef CONFIG_FSFREEZE
  52 #define QGA_FSFREEZE_HOOK_DEFAULT CONFIG_QEMU_CONFDIR "/fsfreeze-hook"
  53 #endif
  54 #define QGA_SENTINEL_BYTE 0xFF
  55
  56 struct GAState {
  57     JSONMessageParser parser;
  58     GMainLoop *main_loop;
  59     GAChannel *channel;
  60     bool virtio; /* fastpath to check for virtio to deal with poll() quirks */
  61     GACommandState *command_state;
  62     GLogLevelFlags log_level;
  63     FILE *log_file;
  64     bool logging_enabled;
  65 #ifdef _WIN32
  66     GAService service;
  67 #endif
  68     bool delimit_response;
  69     bool frozen;
  70     GList *blacklist;
  71     const char *state_filepath_isfrozen;
  72     struct {
  73         const char *log_filepath;
  74         const char *pid_filepath;
  75     } deferred_options;
  76 #ifdef CONFIG_FSFREEZE
  77     const char *fsfreeze_hook;
  78 #endif
  79 };
  80
  81 struct GAState *ga_state;
  82
  83 /* commands that are safe to issue while filesystems are frozen */
  84 static const char *ga_freeze_whitelist[] = {
  85     "guest-ping",
  86     "guest-info",
  87     "guest-sync",
  88     "guest-fsfreeze-status",
  89     "guest-fsfreeze-thaw",
  90     NULL
  91 };
  92
  93 #ifdef _WIN32
  94 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
  95                                   LPVOID ctx);
  96 VOID WINAPI service_main(DWORD argc, TCHAR *argv[]);
  97 #endif
  98
  99 static void quit_handler(int sig)
 100 {
 101     /* if we're frozen, don't exit unless we're absolutely forced to,
 102      * because it's basically impossible for graceful exit to complete
 103      * unless all log/pid files are on unfreezable filesystems. there's
 104      * also a very likely chance killing the agent before unfreezing
 105      * the filesystems is a mistake (or will be viewed as one later).
 106      */
 107     if (ga_is_frozen(ga_state)) {
 108         return;
 109     }
 110     g_debug("received signal num %d, quitting", sig);
 111
 112     if (g_main_loop_is_running(ga_state->main_loop)) {
 113         g_main_loop_quit(ga_state->main_loop);
 114     }
 115 }
 116
 117 #ifndef _WIN32
 118 static gboolean register_signal_handlers(void)
 119 {
 120     struct sigaction sigact;
 121     int ret;
 122
 123     memset(&sigact, 0, sizeof(struct sigaction));
 124     sigact.sa_handler = quit_handler;
 125
 126     ret = sigaction(SIGINT, &sigact, NULL);
 127     if (ret == -1) {
 128         g_error("error configuring signal handler: %s", strerror(errno));
 129     }
 130     ret = sigaction(SIGTERM, &sigact, NULL);
 131     if (ret == -1) {
 132         g_error("error configuring signal handler: %s", strerror(errno));
 133     }
 134
 135     return true;
 136 }
 137
 138 /* TODO: use this in place of all post-fork() fclose(std*) callers */
 139 void reopen_fd_to_null(int fd)
 140 {
 141     int nullfd;
 142
 143     nullfd = open("/dev/null", O_RDWR);
 144     if (nullfd < 0) {
 145         return;
 146     }
 147
 148     dup2(nullfd, fd);
 149
 150     if (nullfd != fd) {
 151         close(nullfd);
 152     }
 153 }
 154 #endif
 155
 156 static void usage(const char *cmd)
 157 {
 158     printf(
 159 "Usage: %s [-m <method> -p <path>] [<options>]\n"
 160 "QEMU Guest Agent %s\n"
 161 "\n"
 162 "  -m, --method      transport method: one of unix-listen, virtio-serial, or\n"
 163 "                    isa-serial (virtio-serial is the default)\n"
 164 "  -p, --path        device/socket path (the default for virtio-serial is:\n"
 165 "                    %s)\n"
 166 "  -l, --logfile     set logfile path, logs to stderr by default\n"
 167 "  -f, --pidfile     specify pidfile (default is %s)\n"
 168 #ifdef CONFIG_FSFREEZE
 169 "  -F, --fsfreeze-hook\n"
 170 "                    enable fsfreeze hook. Accepts an optional argument that\n"
 171 "                    specifies script to run on freeze/thaw. Script will be\n"
 172 "                    called with 'freeze'/'thaw' arguments accordingly.\n"
 173 "                    (default is %s)\n"
 174 "                    If using -F with an argument, do not follow -F with a\n"
 175 "                    space.\n"
 176 "                    (for example: -F/var/run/fsfreezehook.sh)\n"
 177 #endif
 178 "  -t, --statedir    specify dir to store state information (absolute paths\n"
 179 "                    only, default is %s)\n"
 180 "  -v, --verbose     log extra debugging information\n"
 181 "  -V, --version     print version information and exit\n"
 182 "  -d, --daemonize   become a daemon\n"
 183 #ifdef _WIN32
 184 "  -s, --service     service commands: install, uninstall\n"
 185 #endif
 186 "  -b, --blacklist   comma-separated list of RPCs to disable (no spaces, \"?\"\n"
 187 "                    to list available RPCs)\n"
 188 "  -h, --help        display this help and exit\n"
 189 "\n"
 190 "Report bugs to <mdroth@linux.vnet.ibm.com>\n"
 191     , cmd, QEMU_VERSION, QGA_VIRTIO_PATH_DEFAULT, QGA_PIDFILE_DEFAULT,
 192 #ifdef CONFIG_FSFREEZE
 193     QGA_FSFREEZE_HOOK_DEFAULT,
 194 #endif
 195     QGA_STATEDIR_DEFAULT);
 196 }
 197
 198 static const char *ga_log_level_str(GLogLevelFlags level)
 199 {
 200     switch (level & G_LOG_LEVEL_MASK) {
 201         case G_LOG_LEVEL_ERROR:
 202             return "error";
 203         case G_LOG_LEVEL_CRITICAL:
 204             return "critical";
 205         case G_LOG_LEVEL_WARNING:
 206             return "warning";
 207         case G_LOG_LEVEL_MESSAGE:
 208             return "message";
 209         case G_LOG_LEVEL_INFO:
 210             return "info";
 211         case G_LOG_LEVEL_DEBUG:
 212             return "debug";
 213         default:
 214             return "user";
 215     }
 216 }
 217
 218 bool ga_logging_enabled(GAState *s)
 219 {
 220     return s->logging_enabled;
 221 }
 222
 223 void ga_disable_logging(GAState *s)
 224 {
 225     s->logging_enabled = false;
 226 }
 227
 228 void ga_enable_logging(GAState *s)
 229 {
 230     s->logging_enabled = true;
 231 }
 232
 233 static void ga_log(const gchar *domain, GLogLevelFlags level,
 234                    const gchar *msg, gpointer opaque)
 235 {
 236     GAState *s = opaque;
 237     GTimeVal time;
 238     const char *level_str = ga_log_level_str(level);
 239
 240     if (!ga_logging_enabled(s)) {
 241         return;
 242     }
 243
 244     level &= G_LOG_LEVEL_MASK;
 245 #ifndef _WIN32
 246     if (domain && strcmp(domain, "syslog") == 0) {
 247         syslog(LOG_INFO, "%s: %s", level_str, msg);
 248     } else if (level & s->log_level) {
 249 #else
 250     if (level & s->log_level) {
 251 #endif
 252         g_get_current_time(&time);
 253         fprintf(s->log_file,
 254                 "%lu.%lu: %s: %s\n", time.tv_sec, time.tv_usec, level_str, msg);
 255         fflush(s->log_file);
 256     }
 257 }
 258
 259 void ga_set_response_delimited(GAState *s)
 260 {
 261     s->delimit_response = true;
 262 }
 263
 264 static FILE *ga_open_logfile(const char *logfile)
 265 {
 266     FILE *f;
 267
 268     f = fopen(logfile, "a");
 269     if (!f) {
 270         return NULL;
 271     }
 272
 273     qemu_set_cloexec(fileno(f));
 274     return f;
 275 }
 276
 277 #ifndef _WIN32
 278 static bool ga_open_pidfile(const char *pidfile)
 279 {
 280     int pidfd;
 281     char pidstr[32];
 282
 283     pidfd = qemu_open(pidfile, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR);
 284     if (pidfd == -1 || lockf(pidfd, F_TLOCK, 0)) {
 285         g_critical("Cannot lock pid file, %s", strerror(errno));
 286         if (pidfd != -1) {
 287             close(pidfd);
 288         }
 289         return false;
 290     }
 291
 292     if (ftruncate(pidfd, 0) || lseek(pidfd, 0, SEEK_SET)) {
 293         g_critical("Failed to truncate pid file");
 294         goto fail;
 295     }
 296     snprintf(pidstr, sizeof(pidstr), "%d\n", getpid());
 297     if (write(pidfd, pidstr, strlen(pidstr)) != strlen(pidstr)) {
 298         g_critical("Failed to write pid file");
 299         goto fail;
 300     }
 301
 302     return true;
 303
 304 fail:
 305     unlink(pidfile);
 306     return false;
 307 }
 308 #else /* _WIN32 */
 309 static bool ga_open_pidfile(const char *pidfile)
 310 {
 311     return true;
 312 }
 313 #endif
 314
 315 static gint ga_strcmp(gconstpointer str1, gconstpointer str2)
 316 {
 317     return strcmp(str1, str2);
 318 }
 319
 320 /* disable commands that aren't safe for fsfreeze */
 321 static void ga_disable_non_whitelisted(void)
 322 {
 323     char **list_head, **list;
 324     bool whitelisted;
 325     int i;
 326
 327     list_head = list = qmp_get_command_list();
 328     while (*list != NULL) {
 329         whitelisted = false;
 330         i = 0;
 331         while (ga_freeze_whitelist[i] != NULL) {
 332             if (strcmp(*list, ga_freeze_whitelist[i]) == 0) {
 333                 whitelisted = true;
 334             }
 335             i++;
 336         }
 337         if (!whitelisted) {
 338             g_debug("disabling command: %s", *list);
 339             qmp_disable_command(*list);
 340         }
 341         g_free(*list);
 342         list++;
 343     }
 344     g_free(list_head);
 345 }
 346
 347 /* [re-]enable all commands, except those explicitly blacklisted by user */
 348 static void ga_enable_non_blacklisted(GList *blacklist)
 349 {
 350     char **list_head, **list;
 351
 352     list_head = list = qmp_get_command_list();
 353     while (*list != NULL) {
 354         if (g_list_find_custom(blacklist, *list, ga_strcmp) == NULL &&
 355             !qmp_command_is_enabled(*list)) {
 356             g_debug("enabling command: %s", *list);
 357             qmp_enable_command(*list);
 358         }
 359         g_free(*list);
 360         list++;
 361     }
 362     g_free(list_head);
 363 }
 364
 365 static bool ga_create_file(const char *path)
 366 {
 367     int fd = open(path, O_CREAT | O_WRONLY, S_IWUSR | S_IRUSR);
 368     if (fd == -1) {
 369         g_warning("unable to open/create file %s: %s", path, strerror(errno));
 370         return false;
 371     }
 372     close(fd);
 373     return true;
 374 }
 375
 376 static bool ga_delete_file(const char *path)
 377 {
 378     int ret = unlink(path);
 379     if (ret == -1) {
 380         g_warning("unable to delete file: %s: %s", path, strerror(errno));
 381         return false;
 382     }
 383
 384     return true;
 385 }
 386
 387 bool ga_is_frozen(GAState *s)
 388 {
 389     return s->frozen;
 390 }
 391
 392 void ga_set_frozen(GAState *s)
 393 {
 394     if (ga_is_frozen(s)) {
 395         return;
 396     }
 397     /* disable all non-whitelisted (for frozen state) commands */
 398     ga_disable_non_whitelisted();
 399     g_warning("disabling logging due to filesystem freeze");
 400     ga_disable_logging(s);
 401     s->frozen = true;
 402     if (!ga_create_file(s->state_filepath_isfrozen)) {
 403         g_warning("unable to create %s, fsfreeze may not function properly",
 404                   s->state_filepath_isfrozen);
 405     }
 406 }
 407
 408 void ga_unset_frozen(GAState *s)
 409 {
 410     if (!ga_is_frozen(s)) {
 411         return;
 412     }
 413
 414     /* if we delayed creation/opening of pid/log files due to being
 415      * in a frozen state at start up, do it now
 416      */
 417     if (s->deferred_options.log_filepath) {
 418         s->log_file = ga_open_logfile(s->deferred_options.log_filepath);
 419         if (!s->log_file) {
 420             s->log_file = stderr;
 421         }
 422         s->deferred_options.log_filepath = NULL;
 423     }
 424     ga_enable_logging(s);
 425     g_warning("logging re-enabled due to filesystem unfreeze");
 426     if (s->deferred_options.pid_filepath) {
 427         if (!ga_open_pidfile(s->deferred_options.pid_filepath)) {
 428             g_warning("failed to create/open pid file");
 429         }
 430         s->deferred_options.pid_filepath = NULL;
 431     }
 432
 433     /* enable all disabled, non-blacklisted commands */
 434     ga_enable_non_blacklisted(s->blacklist);
 435     s->frozen = false;
 436     if (!ga_delete_file(s->state_filepath_isfrozen)) {
 437         g_warning("unable to delete %s, fsfreeze may not function properly",
 438                   s->state_filepath_isfrozen);
 439     }
 440 }
 441
 442 #ifdef CONFIG_FSFREEZE
 443 const char *ga_fsfreeze_hook(GAState *s)
 444 {
 445     return s->fsfreeze_hook;
 446 }
 447 #endif
 448
 449 static void become_daemon(const char *pidfile)
 450 {
 451 #ifndef _WIN32
 452     pid_t pid, sid;
 453
 454     pid = fork();
 455     if (pid < 0) {
 456         exit(EXIT_FAILURE);
 457     }
 458     if (pid > 0) {
 459         exit(EXIT_SUCCESS);
 460     }
 461
 462     if (pidfile) {
 463         if (!ga_open_pidfile(pidfile)) {
 464             g_critical("failed to create pidfile");
 465             exit(EXIT_FAILURE);
 466         }
 467     }
 468
 469     umask(0);
 470     sid = setsid();
 471     if (sid < 0) {
 472         goto fail;
 473     }
 474     if ((chdir("/")) < 0) {
 475         goto fail;
 476     }
 477
 478     reopen_fd_to_null(STDIN_FILENO);
 479     reopen_fd_to_null(STDOUT_FILENO);
 480     reopen_fd_to_null(STDERR_FILENO);
 481     return;
 482
 483 fail:
 484     if (pidfile) {
 485         unlink(pidfile);
 486     }
 487     g_critical("failed to daemonize");
 488     exit(EXIT_FAILURE);
 489 #endif
 490 }
 491
 492 static int send_response(GAState *s, QObject *payload)
 493 {
 494     const char *buf;
 495     QString *payload_qstr, *response_qstr;
 496     GIOStatus status;
 497
 498     g_assert(payload && s->channel);
 499
 500     payload_qstr = qobject_to_json(payload);
 501     if (!payload_qstr) {
 502         return -EINVAL;
 503     }
 504
 505     if (s->delimit_response) {
 506         s->delimit_response = false;
 507         response_qstr = qstring_new();
 508         qstring_append_chr(response_qstr, QGA_SENTINEL_BYTE);
 509         qstring_append(response_qstr, qstring_get_str(payload_qstr));
 510         QDECREF(payload_qstr);
 511     } else {
 512         response_qstr = payload_qstr;
 513     }
 514
 515     qstring_append_chr(response_qstr, '\n');
 516     buf = qstring_get_str(response_qstr);
 517     status = ga_channel_write_all(s->channel, buf, strlen(buf));
 518     QDECREF(response_qstr);
 519     if (status != G_IO_STATUS_NORMAL) {
 520         return -EIO;
 521     }
 522
 523     return 0;
 524 }
 525
 526 static void process_command(GAState *s, QDict *req)
 527 {
 528     QObject *rsp = NULL;
 529     int ret;
 530
 531     g_assert(req);
 532     g_debug("processing command");
 533     rsp = qmp_dispatch(QOBJECT(req));
 534     if (rsp) {
 535         ret = send_response(s, rsp);
 536         if (ret) {
 537             g_warning("error sending response: %s", strerror(ret));
 538         }
 539         qobject_decref(rsp);
 540     }
 541 }
 542
 543 /* handle requests/control events coming in over the channel */
 544 static void process_event(JSONMessageParser *parser, QList *tokens)
 545 {
 546     GAState *s = container_of(parser, GAState, parser);
 547     QObject *obj;
 548     QDict *qdict;
 549     Error *err = NULL;
 550     int ret;
 551
 552     g_assert(s && parser);
 553
 554     g_debug("process_event: called");
 555     obj = json_parser_parse_err(tokens, NULL, &err);
 556     if (err || !obj || qobject_type(obj) != QTYPE_QDICT) {
 557         qobject_decref(obj);
 558         qdict = qdict_new();
 559         if (!err) {
 560             g_warning("failed to parse event: unknown error");
 561             error_set(&err, QERR_JSON_PARSING);
 562         } else {
 563             g_warning("failed to parse event: %s", error_get_pretty(err));
 564         }
 565         qdict_put_obj(qdict, "error", qmp_build_error_object(err));
 566         error_free(err);
 567     } else {
 568         qdict = qobject_to_qdict(obj);
 569     }
 570
 571     g_assert(qdict);
 572
 573     /* handle host->guest commands */
 574     if (qdict_haskey(qdict, "execute")) {
 575         process_command(s, qdict);
 576     } else {
 577         if (!qdict_haskey(qdict, "error")) {
 578             QDECREF(qdict);
 579             qdict = qdict_new();
 580             g_warning("unrecognized payload format");
 581             error_set(&err, QERR_UNSUPPORTED);
 582             qdict_put_obj(qdict, "error", qmp_build_error_object(err));
 583             error_free(err);
 584         }
 585         ret = send_response(s, QOBJECT(qdict));
 586         if (ret) {
 587             g_warning("error sending error response: %s", strerror(ret));
 588         }
 589     }
 590
 591     QDECREF(qdict);
 592 }
 593
 594 /* false return signals GAChannel to close the current client connection */
 595 static gboolean channel_event_cb(GIOCondition condition, gpointer data)
 596 {
 597     GAState *s = data;
 598     gchar buf[QGA_READ_COUNT_DEFAULT+1];
 599     gsize count;
 600     GError *err = NULL;
 601     GIOStatus status = ga_channel_read(s->channel, buf, QGA_READ_COUNT_DEFAULT, &count);
 602     if (err != NULL) {
 603         g_warning("error reading channel: %s", err->message);
 604         g_error_free(err);
 605         return false;
 606     }
 607     switch (status) {
 608     case G_IO_STATUS_ERROR:
 609         g_warning("error reading channel");
 610         return false;
 611     case G_IO_STATUS_NORMAL:
 612         buf[count] = 0;
 613         g_debug("read data, count: %d, data: %s", (int)count, buf);
 614         json_message_parser_feed(&s->parser, (char *)buf, (int)count);
 615         break;
 616     case G_IO_STATUS_EOF:
 617         g_debug("received EOF");
 618         if (!s->virtio) {
 619             return false;
 620         }
 621         /* fall through */
 622     case G_IO_STATUS_AGAIN:
 623         /* virtio causes us to spin here when no process is attached to
 624          * host-side chardev. sleep a bit to mitigate this
 625          */
 626         if (s->virtio) {
 627             usleep(100*1000);
 628         }
 629         return true;
 630     default:
 631         g_warning("unknown channel read status, closing");
 632         return false;
 633     }
 634     return true;
 635 }
 636
 637 static gboolean channel_init(GAState *s, const gchar *method, const gchar *path)
 638 {
 639     GAChannelMethod channel_method;
 640
 641     if (method == NULL) {
 642         method = "virtio-serial";
 643     }
 644
 645     if (path == NULL) {
 646         if (strcmp(method, "virtio-serial") != 0) {
 647             g_critical("must specify a path for this channel");
 648             return false;
 649         }
 650         /* try the default path for the virtio-serial port */
 651         path = QGA_VIRTIO_PATH_DEFAULT;
 652     }
 653
 654     if (strcmp(method, "virtio-serial") == 0) {
 655         s->virtio = true; /* virtio requires special handling in some cases */
 656         channel_method = GA_CHANNEL_VIRTIO_SERIAL;
 657     } else if (strcmp(method, "isa-serial") == 0) {
 658         channel_method = GA_CHANNEL_ISA_SERIAL;
 659     } else if (strcmp(method, "unix-listen") == 0) {
 660         channel_method = GA_CHANNEL_UNIX_LISTEN;
 661     } else {
 662         g_critical("unsupported channel method/type: %s", method);
 663         return false;
 664     }
 665
 666     s->channel = ga_channel_new(channel_method, path, channel_event_cb, s);
 667     if (!s->channel) {
 668         g_critical("failed to create guest agent channel");
 669         return false;
 670     }
 671
 672     return true;
 673 }
 674
 675 #ifdef _WIN32
 676 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
 677                                   LPVOID ctx)
 678 {
 679     DWORD ret = NO_ERROR;
 680     GAService *service = &ga_state->service;
 681
 682     switch (ctrl)
 683     {
 684         case SERVICE_CONTROL_STOP:
 685         case SERVICE_CONTROL_SHUTDOWN:
 686             quit_handler(SIGTERM);
 687             service->status.dwCurrentState = SERVICE_STOP_PENDING;
 688             SetServiceStatus(service->status_handle, &service->status);
 689             break;
 690
 691         default:
 692             ret = ERROR_CALL_NOT_IMPLEMENTED;
 693     }
 694     return ret;
 695 }
 696
 697 VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
 698 {
 699     GAService *service = &ga_state->service;
 700
 701     service->status_handle = RegisterServiceCtrlHandlerEx(QGA_SERVICE_NAME,
 702         service_ctrl_handler, NULL);
 703
 704     if (service->status_handle == 0) {
 705         g_critical("Failed to register extended requests function!\n");
 706         return;
 707     }
 708
 709     service->status.dwServiceType = SERVICE_WIN32;
 710     service->status.dwCurrentState = SERVICE_RUNNING;
 711     service->status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 712     service->status.dwWin32ExitCode = NO_ERROR;
 713     service->status.dwServiceSpecificExitCode = NO_ERROR;
 714     service->status.dwCheckPoint = 0;
 715     service->status.dwWaitHint = 0;
 716     SetServiceStatus(service->status_handle, &service->status);
 717
 718     g_main_loop_run(ga_state->main_loop);
 719
 720     service->status.dwCurrentState = SERVICE_STOPPED;
 721     SetServiceStatus(service->status_handle, &service->status);
 722 }
 723 #endif
 724
 725 int main(int argc, char **argv)
 726 {
 727     const char *sopt = "hVvdm:p:l:f:F::b:s:t:";
 728     const char *method = NULL, *path = NULL;
 729     const char *log_filepath = NULL;
 730     const char *pid_filepath = QGA_PIDFILE_DEFAULT;
 731 #ifdef CONFIG_FSFREEZE
 732     const char *fsfreeze_hook = NULL;
 733 #endif
 734     const char *state_dir = QGA_STATEDIR_DEFAULT;
 735 #ifdef _WIN32
 736     const char *service = NULL;
 737 #endif
 738     const struct option lopt[] = {
 739         { "help", 0, NULL, 'h' },
 740         { "version", 0, NULL, 'V' },
 741         { "logfile", 1, NULL, 'l' },
 742         { "pidfile", 1, NULL, 'f' },
 743 #ifdef CONFIG_FSFREEZE
 744         { "fsfreeze-hook", 2, NULL, 'F' },
 745 #endif
 746         { "verbose", 0, NULL, 'v' },
 747         { "method", 1, NULL, 'm' },
 748         { "path", 1, NULL, 'p' },
 749         { "daemonize", 0, NULL, 'd' },
 750         { "blacklist", 1, NULL, 'b' },
 751 #ifdef _WIN32
 752         { "service", 1, NULL, 's' },
 753 #endif
 754         { "statedir", 1, NULL, 't' },
 755         { NULL, 0, NULL, 0 }
 756     };
 757     int opt_ind = 0, ch, daemonize = 0, i, j, len;
 758     GLogLevelFlags log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
 759     GList *blacklist = NULL;
 760     GAState *s;
 761
 762     module_call_init(MODULE_INIT_QAPI);
 763
 764     while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
 765         switch (ch) {
 766         case 'm':
 767             method = optarg;
 768             break;
 769         case 'p':
 770             path = optarg;
 771             break;
 772         case 'l':
 773             log_filepath = optarg;
 774             break;
 775         case 'f':
 776             pid_filepath = optarg;
 777             break;
 778 #ifdef CONFIG_FSFREEZE
 779         case 'F':
 780             fsfreeze_hook = optarg ? optarg : QGA_FSFREEZE_HOOK_DEFAULT;
 781             break;
 782 #endif
 783         case 't':
 784              state_dir = optarg;
 785              break;
 786         case 'v':
 787             /* enable all log levels */
 788             log_level = G_LOG_LEVEL_MASK;
 789             break;
 790         case 'V':
 791             printf("QEMU Guest Agent %s\n", QEMU_VERSION);
 792             return 0;
 793         case 'd':
 794             daemonize = 1;
 795             break;
 796         case 'b': {
 797             char **list_head, **list;
 798             if (is_help_option(optarg)) {
 799                 list_head = list = qmp_get_command_list();
 800                 while (*list != NULL) {
 801                     printf("%s\n", *list);
 802                     g_free(*list);
 803                     list++;
 804                 }
 805                 g_free(list_head);
 806                 return 0;
 807             }
 808             for (j = 0, i = 0, len = strlen(optarg); i < len; i++) {
 809                 if (optarg[i] == ',') {
 810                     optarg[i] = 0;
 811                     blacklist = g_list_append(blacklist, &optarg[j]);
 812                     j = i + 1;
 813                 }
 814             }
 815             if (j < i) {
 816                 blacklist = g_list_append(blacklist, &optarg[j]);
 817             }
 818             break;
 819         }
 820 #ifdef _WIN32
 821         case 's':
 822             service = optarg;
 823             if (strcmp(service, "install") == 0) {
 824                 return ga_install_service(path, log_filepath);
 825             } else if (strcmp(service, "uninstall") == 0) {
 826                 return ga_uninstall_service();
 827             } else {
 828                 printf("Unknown service command.\n");
 829                 return EXIT_FAILURE;
 830             }
 831             break;
 832 #endif
 833         case 'h':
 834             usage(argv[0]);
 835             return 0;
 836         case '?':
 837             g_print("Unknown option, try '%s --help' for more information.\n",
 838                     argv[0]);
 839             return EXIT_FAILURE;
 840         }
 841     }
 842
 843     s = g_malloc0(sizeof(GAState));
 844     s->log_level = log_level;
 845     s->log_file = stderr;
 846 #ifdef CONFIG_FSFREEZE
 847     s->fsfreeze_hook = fsfreeze_hook;
 848 #endif
 849     g_log_set_default_handler(ga_log, s);
 850     g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
 851     ga_enable_logging(s);
 852     s->state_filepath_isfrozen = g_strdup_printf("%s/qga.state.isfrozen",
 853                                                  state_dir);
 854     s->frozen = false;
 855 #ifndef _WIN32
 856     /* check if a previous instance of qemu-ga exited with filesystems' state
 857      * marked as frozen. this could be a stale value (a non-qemu-ga process
 858      * or reboot may have since unfrozen them), but better to require an
 859      * uneeded unfreeze than to risk hanging on start-up
 860      */
 861     struct stat st;
 862     if (stat(s->state_filepath_isfrozen, &st) == -1) {
 863         /* it's okay if the file doesn't exist, but if we can't access for
 864          * some other reason, such as permissions, there's a configuration
 865          * that needs to be addressed. so just bail now before we get into
 866          * more trouble later
 867          */
 868         if (errno != ENOENT) {
 869             g_critical("unable to access state file at path %s: %s",
 870                        s->state_filepath_isfrozen, strerror(errno));
 871             return EXIT_FAILURE;
 872         }
 873     } else {
 874         g_warning("previous instance appears to have exited with frozen"
 875                   " filesystems. deferring logging/pidfile creation and"
 876                   " disabling non-fsfreeze-safe commands until"
 877                   " guest-fsfreeze-thaw is issued, or filesystems are"
 878                   " manually unfrozen and the file %s is removed",
 879                   s->state_filepath_isfrozen);
 880         s->frozen = true;
 881     }
 882 #endif
 883
 884     if (ga_is_frozen(s)) {
 885         if (daemonize) {
 886             /* delay opening/locking of pidfile till filesystem are unfrozen */
 887             s->deferred_options.pid_filepath = pid_filepath;
 888             become_daemon(NULL);
 889         }
 890         if (log_filepath) {
 891             /* delay opening the log file till filesystems are unfrozen */
 892             s->deferred_options.log_filepath = log_filepath;
 893         }
 894         ga_disable_logging(s);
 895         ga_disable_non_whitelisted();
 896     } else {
 897         if (daemonize) {
 898             become_daemon(pid_filepath);
 899         }
 900         if (log_filepath) {
 901             FILE *log_file = ga_open_logfile(log_filepath);
 902             if (!log_file) {
 903                 g_critical("unable to open specified log file: %s",
 904                            strerror(errno));
 905                 goto out_bad;
 906             }
 907             s->log_file = log_file;
 908         }
 909     }
 910
 911     if (blacklist) {
 912         s->blacklist = blacklist;
 913         do {
 914             g_debug("disabling command: %s", (char *)blacklist->data);
 915             qmp_disable_command(blacklist->data);
 916             blacklist = g_list_next(blacklist);
 917         } while (blacklist);
 918     }
 919     s->command_state = ga_command_state_new();
 920     ga_command_state_init(s, s->command_state);
 921     ga_command_state_init_all(s->command_state);
 922     json_message_parser_init(&s->parser, process_event);
 923     ga_state = s;
 924 #ifndef _WIN32
 925     if (!register_signal_handlers()) {
 926         g_critical("failed to register signal handlers");
 927         goto out_bad;
 928     }
 929 #endif
 930
 931     s->main_loop = g_main_loop_new(NULL, false);
 932     if (!channel_init(ga_state, method, path)) {
 933         g_critical("failed to initialize guest agent channel");
 934         goto out_bad;
 935     }
 936 #ifndef _WIN32
 937     g_main_loop_run(ga_state->main_loop);
 938 #else
 939     if (daemonize) {
 940         SERVICE_TABLE_ENTRY service_table[] = {
 941             { (char *)QGA_SERVICE_NAME, service_main }, { NULL, NULL } };
 942         StartServiceCtrlDispatcher(service_table);
 943     } else {
 944         g_main_loop_run(ga_state->main_loop);
 945     }
 946 #endif
 947
 948     ga_command_state_cleanup_all(ga_state->command_state);
 949     ga_channel_free(ga_state->channel);
 950
 951     if (daemonize) {
 952         unlink(pid_filepath);
 953     }
 954     return 0;
 955
 956 out_bad:
 957     if (daemonize) {
 958         unlink(pid_filepath);
 959     }
 960     return EXIT_FAILURE;
 961 }