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
  14 #include "qemu/osdep.h"
  15 #include <getopt.h>
  16 #include <glib/gstdio.h>
  17 #ifndef _WIN32
  18 #include <syslog.h>
  19 #include <sys/wait.h>
  20 #endif
  21 #include "qapi/qmp/json-parser.h"
  22 #include "qapi/qmp/qdict.h"
  23 #include "qapi/qmp/qjson.h"
  24 #include "qapi/qmp/qstring.h"
  25 #include "guest-agent-core.h"
  26 #include "qemu/module.h"
  27 #include "qga-qapi-commands.h"
  28 #include "qapi/qmp/qerror.h"
  29 #include "qapi/error.h"
  30 #include "channel.h"
  31 #include "qemu/bswap.h"
  32 #include "qemu/help_option.h"
  33 #include "qemu/sockets.h"
  34 #include "qemu/systemd.h"
  35 #include "qemu-version.h"
  36 #ifdef _WIN32
  37 #include "qga/service-win32.h"
  38 #include "qga/vss-win32.h"
  39 #endif
  40 #ifdef __linux__
  41 #include <linux/fs.h>
  42 #ifdef FIFREEZE
  43 #define CONFIG_FSFREEZE
  44 #endif
  45 #endif
  46
  47 #ifndef _WIN32
  48 #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
  49 #define QGA_STATE_RELATIVE_DIR  "run"
  50 #define QGA_SERIAL_PATH_DEFAULT "/dev/ttyS0"
  51 #else
  52 #define QGA_VIRTIO_PATH_DEFAULT "\\\\.\\Global\\org.qemu.guest_agent.0"
  53 #define QGA_STATE_RELATIVE_DIR  "qemu-ga"
  54 #define QGA_SERIAL_PATH_DEFAULT "COM1"
  55 #endif
  56 #ifdef CONFIG_FSFREEZE
  57 #define QGA_FSFREEZE_HOOK_DEFAULT CONFIG_QEMU_CONFDIR "/fsfreeze-hook"
  58 #endif
  59 #define QGA_SENTINEL_BYTE 0xFF
  60 #define QGA_CONF_DEFAULT CONFIG_QEMU_CONFDIR G_DIR_SEPARATOR_S "qemu-ga.conf"
  61
  62 static struct {
  63     const char *state_dir;
  64     const char *pidfile;
  65 } dfl_pathnames;
  66
  67 typedef struct GAPersistentState {
  68 #define QGA_PSTATE_DEFAULT_FD_COUNTER 1000
  69     int64_t fd_counter;
  70 } GAPersistentState;
  71
  72 struct GAState {
  73     JSONMessageParser parser;
  74     GMainLoop *main_loop;
  75     GAChannel *channel;
  76     bool virtio; /* fastpath to check for virtio to deal with poll() quirks */
  77     GACommandState *command_state;
  78     GLogLevelFlags log_level;
  79     FILE *log_file;
  80     bool logging_enabled;
  81 #ifdef _WIN32
  82     GAService service;
  83 #endif
  84     bool delimit_response;
  85     bool frozen;
  86     GList *blacklist;
  87     char *state_filepath_isfrozen;
  88     struct {
  89         const char *log_filepath;
  90         const char *pid_filepath;
  91     } deferred_options;
  92 #ifdef CONFIG_FSFREEZE
  93     const char *fsfreeze_hook;
  94 #endif
  95     gchar *pstate_filepath;
  96     GAPersistentState pstate;
  97 };
  98
  99 struct GAState *ga_state;
 100 QmpCommandList ga_commands;
 101
 102 /* commands that are safe to issue while filesystems are frozen */
 103 static const char *ga_freeze_whitelist[] = {
 104     "guest-ping",
 105     "guest-info",
 106     "guest-sync",
 107     "guest-sync-delimited",
 108     "guest-fsfreeze-status",
 109     "guest-fsfreeze-thaw",
 110     NULL
 111 };
 112
 113 #ifdef _WIN32
 114 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
 115                                   LPVOID ctx);
 116 VOID WINAPI service_main(DWORD argc, TCHAR *argv[]);
 117 #endif
 118
 119 static void
 120 init_dfl_pathnames(void)
 121 {
 122     g_assert(dfl_pathnames.state_dir == NULL);
 123     g_assert(dfl_pathnames.pidfile == NULL);
 124     dfl_pathnames.state_dir = qemu_get_local_state_pathname(
 125       QGA_STATE_RELATIVE_DIR);
 126     dfl_pathnames.pidfile   = qemu_get_local_state_pathname(
 127       QGA_STATE_RELATIVE_DIR G_DIR_SEPARATOR_S "qemu-ga.pid");
 128 }
 129
 130 static void quit_handler(int sig)
 131 {
 132     /* if we're frozen, don't exit unless we're absolutely forced to,
 133      * because it's basically impossible for graceful exit to complete
 134      * unless all log/pid files are on unfreezable filesystems. there's
 135      * also a very likely chance killing the agent before unfreezing
 136      * the filesystems is a mistake (or will be viewed as one later).
 137      * On Windows the freeze interval is limited to 10 seconds, so
 138      * we should quit, but first we should wait for the timeout, thaw
 139      * the filesystem and quit.
 140      */
 141     if (ga_is_frozen(ga_state)) {
 142 #ifdef _WIN32
 143         int i = 0;
 144         Error *err = NULL;
 145         HANDLE hEventTimeout;
 146
 147         g_debug("Thawing filesystems before exiting");
 148
 149         hEventTimeout = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_TIMEOUT);
 150         if (hEventTimeout) {
 151             WaitForSingleObject(hEventTimeout, 0);
 152             CloseHandle(hEventTimeout);
 153         }
 154         qga_vss_fsfreeze(&i, false, &err);
 155         if (err) {
 156             g_debug("Error unfreezing filesystems prior to exiting: %s",
 157                 error_get_pretty(err));
 158             error_free(err);
 159         }
 160 #else
 161         return;
 162 #endif
 163     }
 164     g_debug("received signal num %d, quitting", sig);
 165
 166     if (g_main_loop_is_running(ga_state->main_loop)) {
 167         g_main_loop_quit(ga_state->main_loop);
 168     }
 169 }
 170
 171 #ifndef _WIN32
 172 static gboolean register_signal_handlers(void)
 173 {
 174     struct sigaction sigact;
 175     int ret;
 176
 177     memset(&sigact, 0, sizeof(struct sigaction));
 178     sigact.sa_handler = quit_handler;
 179
 180     ret = sigaction(SIGINT, &sigact, NULL);
 181     if (ret == -1) {
 182         g_error("error configuring signal handler: %s", strerror(errno));
 183     }
 184     ret = sigaction(SIGTERM, &sigact, NULL);
 185     if (ret == -1) {
 186         g_error("error configuring signal handler: %s", strerror(errno));
 187     }
 188
 189     sigact.sa_handler = SIG_IGN;
 190     if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
 191         g_error("error configuring SIGPIPE signal handler: %s",
 192                 strerror(errno));
 193     }
 194
 195     return true;
 196 }
 197
 198 /* TODO: use this in place of all post-fork() fclose(std*) callers */
 199 void reopen_fd_to_null(int fd)
 200 {
 201     int nullfd;
 202
 203     nullfd = open("/dev/null", O_RDWR);
 204     if (nullfd < 0) {
 205         return;
 206     }
 207
 208     dup2(nullfd, fd);
 209
 210     if (nullfd != fd) {
 211         close(nullfd);
 212     }
 213 }
 214 #endif
 215
 216 static void usage(const char *cmd)
 217 {
 218     printf(
 219 "Usage: %s [-m <method> -p <path>] [<options>]\n"
 220 "QEMU Guest Agent " QEMU_FULL_VERSION "\n"
 221 QEMU_COPYRIGHT "\n"
 222 "\n"
 223 "  -m, --method      transport method: one of unix-listen, virtio-serial,\n"
 224 "                    isa-serial, or vsock-listen (virtio-serial is the default)\n"
 225 "  -p, --path        device/socket path (the default for virtio-serial is:\n"
 226 "                    %s,\n"
 227 "                    the default for isa-serial is:\n"
 228 "                    %s)\n"
 229 "  -l, --logfile     set logfile path, logs to stderr by default\n"
 230 "  -f, --pidfile     specify pidfile (default is %s)\n"
 231 #ifdef CONFIG_FSFREEZE
 232 "  -F, --fsfreeze-hook\n"
 233 "                    enable fsfreeze hook. Accepts an optional argument that\n"
 234 "                    specifies script to run on freeze/thaw. Script will be\n"
 235 "                    called with 'freeze'/'thaw' arguments accordingly.\n"
 236 "                    (default is %s)\n"
 237 "                    If using -F with an argument, do not follow -F with a\n"
 238 "                    space.\n"
 239 "                    (for example: -F/var/run/fsfreezehook.sh)\n"
 240 #endif
 241 "  -t, --statedir    specify dir to store state information (absolute paths\n"
 242 "                    only, default is %s)\n"
 243 "  -v, --verbose     log extra debugging information\n"
 244 "  -V, --version     print version information and exit\n"
 245 "  -d, --daemonize   become a daemon\n"
 246 #ifdef _WIN32
 247 "  -s, --service     service commands: install, uninstall, vss-install, vss-uninstall\n"
 248 #endif
 249 "  -b, --blacklist   comma-separated list of RPCs to disable (no spaces, \"?\"\n"
 250 "                    to list available RPCs)\n"
 251 "  -D, --dump-conf   dump a qemu-ga config file based on current config\n"
 252 "                    options / command-line parameters to stdout\n"
 253 "  -h, --help        display this help and exit\n"
 254 "\n"
 255 QEMU_HELP_BOTTOM "\n"
 256     , cmd, QGA_VIRTIO_PATH_DEFAULT, QGA_SERIAL_PATH_DEFAULT,
 257     dfl_pathnames.pidfile,
 258 #ifdef CONFIG_FSFREEZE
 259     QGA_FSFREEZE_HOOK_DEFAULT,
 260 #endif
 261     dfl_pathnames.state_dir);
 262 }
 263
 264 static const char *ga_log_level_str(GLogLevelFlags level)
 265 {
 266     switch (level & G_LOG_LEVEL_MASK) {
 267         case G_LOG_LEVEL_ERROR:
 268             return "error";
 269         case G_LOG_LEVEL_CRITICAL:
 270             return "critical";
 271         case G_LOG_LEVEL_WARNING:
 272             return "warning";
 273         case G_LOG_LEVEL_MESSAGE:
 274             return "message";
 275         case G_LOG_LEVEL_INFO:
 276             return "info";
 277         case G_LOG_LEVEL_DEBUG:
 278             return "debug";
 279         default:
 280             return "user";
 281     }
 282 }
 283
 284 bool ga_logging_enabled(GAState *s)
 285 {
 286     return s->logging_enabled;
 287 }
 288
 289 void ga_disable_logging(GAState *s)
 290 {
 291     s->logging_enabled = false;
 292 }
 293
 294 void ga_enable_logging(GAState *s)
 295 {
 296     s->logging_enabled = true;
 297 }
 298
 299 static void ga_log(const gchar *domain, GLogLevelFlags level,
 300                    const gchar *msg, gpointer opaque)
 301 {
 302     GAState *s = opaque;
 303     GTimeVal time;
 304     const char *level_str = ga_log_level_str(level);
 305
 306     if (!ga_logging_enabled(s)) {
 307         return;
 308     }
 309
 310     level &= G_LOG_LEVEL_MASK;
 311 #ifndef _WIN32
 312     if (g_strcmp0(domain, "syslog") == 0) {
 313         syslog(LOG_INFO, "%s: %s", level_str, msg);
 314     } else if (level & s->log_level) {
 315 #else
 316     if (level & s->log_level) {
 317 #endif
 318         g_get_current_time(&time);
 319         fprintf(s->log_file,
 320                 "%lu.%lu: %s: %s\n", time.tv_sec, time.tv_usec, level_str, msg);
 321         fflush(s->log_file);
 322     }
 323 }
 324
 325 void ga_set_response_delimited(GAState *s)
 326 {
 327     s->delimit_response = true;
 328 }
 329
 330 static FILE *ga_open_logfile(const char *logfile)
 331 {
 332     FILE *f;
 333
 334     f = fopen(logfile, "a");
 335     if (!f) {
 336         return NULL;
 337     }
 338
 339     qemu_set_cloexec(fileno(f));
 340     return f;
 341 }
 342
 343 #ifndef _WIN32
 344 static bool ga_open_pidfile(const char *pidfile)
 345 {
 346     int pidfd;
 347     char pidstr[32];
 348
 349     pidfd = qemu_open(pidfile, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR);
 350     if (pidfd == -1 || lockf(pidfd, F_TLOCK, 0)) {
 351         g_critical("Cannot lock pid file, %s", strerror(errno));
 352         if (pidfd != -1) {
 353             close(pidfd);
 354         }
 355         return false;
 356     }
 357
 358     if (ftruncate(pidfd, 0)) {
 359         g_critical("Failed to truncate pid file");
 360         goto fail;
 361     }
 362     snprintf(pidstr, sizeof(pidstr), "%d\n", getpid());
 363     if (write(pidfd, pidstr, strlen(pidstr)) != strlen(pidstr)) {
 364         g_critical("Failed to write pid file");
 365         goto fail;
 366     }
 367
 368     /* keep pidfile open & locked forever */
 369     return true;
 370
 371 fail:
 372     unlink(pidfile);
 373     close(pidfd);
 374     return false;
 375 }
 376 #else /* _WIN32 */
 377 static bool ga_open_pidfile(const char *pidfile)
 378 {
 379     return true;
 380 }
 381 #endif
 382
 383 static gint ga_strcmp(gconstpointer str1, gconstpointer str2)
 384 {
 385     return strcmp(str1, str2);
 386 }
 387
 388 /* disable commands that aren't safe for fsfreeze */
 389 static void ga_disable_non_whitelisted(QmpCommand *cmd, void *opaque)
 390 {
 391     bool whitelisted = false;
 392     int i = 0;
 393     const char *name = qmp_command_name(cmd);
 394
 395     while (ga_freeze_whitelist[i] != NULL) {
 396         if (strcmp(name, ga_freeze_whitelist[i]) == 0) {
 397             whitelisted = true;
 398         }
 399         i++;
 400     }
 401     if (!whitelisted) {
 402         g_debug("disabling command: %s", name);
 403         qmp_disable_command(&ga_commands, name);
 404     }
 405 }
 406
 407 /* [re-]enable all commands, except those explicitly blacklisted by user */
 408 static void ga_enable_non_blacklisted(QmpCommand *cmd, void *opaque)
 409 {
 410     GList *blacklist = opaque;
 411     const char *name = qmp_command_name(cmd);
 412
 413     if (g_list_find_custom(blacklist, name, ga_strcmp) == NULL &&
 414         !qmp_command_is_enabled(cmd)) {
 415         g_debug("enabling command: %s", name);
 416         qmp_enable_command(&ga_commands, name);
 417     }
 418 }
 419
 420 static bool ga_create_file(const char *path)
 421 {
 422     int fd = open(path, O_CREAT | O_WRONLY, S_IWUSR | S_IRUSR);
 423     if (fd == -1) {
 424         g_warning("unable to open/create file %s: %s", path, strerror(errno));
 425         return false;
 426     }
 427     close(fd);
 428     return true;
 429 }
 430
 431 static bool ga_delete_file(const char *path)
 432 {
 433     int ret = unlink(path);
 434     if (ret == -1) {
 435         g_warning("unable to delete file: %s: %s", path, strerror(errno));
 436         return false;
 437     }
 438
 439     return true;
 440 }
 441
 442 bool ga_is_frozen(GAState *s)
 443 {
 444     return s->frozen;
 445 }
 446
 447 void ga_set_frozen(GAState *s)
 448 {
 449     if (ga_is_frozen(s)) {
 450         return;
 451     }
 452     /* disable all non-whitelisted (for frozen state) commands */
 453     qmp_for_each_command(&ga_commands, ga_disable_non_whitelisted, NULL);
 454     g_warning("disabling logging due to filesystem freeze");
 455     ga_disable_logging(s);
 456     s->frozen = true;
 457     if (!ga_create_file(s->state_filepath_isfrozen)) {
 458         g_warning("unable to create %s, fsfreeze may not function properly",
 459                   s->state_filepath_isfrozen);
 460     }
 461 }
 462
 463 void ga_unset_frozen(GAState *s)
 464 {
 465     if (!ga_is_frozen(s)) {
 466         return;
 467     }
 468
 469     /* if we delayed creation/opening of pid/log files due to being
 470      * in a frozen state at start up, do it now
 471      */
 472     if (s->deferred_options.log_filepath) {
 473         s->log_file = ga_open_logfile(s->deferred_options.log_filepath);
 474         if (!s->log_file) {
 475             s->log_file = stderr;
 476         }
 477         s->deferred_options.log_filepath = NULL;
 478     }
 479     ga_enable_logging(s);
 480     g_warning("logging re-enabled due to filesystem unfreeze");
 481     if (s->deferred_options.pid_filepath) {
 482         if (!ga_open_pidfile(s->deferred_options.pid_filepath)) {
 483             g_warning("failed to create/open pid file");
 484         }
 485         s->deferred_options.pid_filepath = NULL;
 486     }
 487
 488     /* enable all disabled, non-blacklisted commands */
 489     qmp_for_each_command(&ga_commands, ga_enable_non_blacklisted, s->blacklist);
 490     s->frozen = false;
 491     if (!ga_delete_file(s->state_filepath_isfrozen)) {
 492         g_warning("unable to delete %s, fsfreeze may not function properly",
 493                   s->state_filepath_isfrozen);
 494     }
 495 }
 496
 497 #ifdef CONFIG_FSFREEZE
 498 const char *ga_fsfreeze_hook(GAState *s)
 499 {
 500     return s->fsfreeze_hook;
 501 }
 502 #endif
 503
 504 static void become_daemon(const char *pidfile)
 505 {
 506 #ifndef _WIN32
 507     pid_t pid, sid;
 508
 509     pid = fork();
 510     if (pid < 0) {
 511         exit(EXIT_FAILURE);
 512     }
 513     if (pid > 0) {
 514         exit(EXIT_SUCCESS);
 515     }
 516
 517     if (pidfile) {
 518         if (!ga_open_pidfile(pidfile)) {
 519             g_critical("failed to create pidfile");
 520             exit(EXIT_FAILURE);
 521         }
 522     }
 523
 524     umask(S_IRWXG | S_IRWXO);
 525     sid = setsid();
 526     if (sid < 0) {
 527         goto fail;
 528     }
 529     if ((chdir("/")) < 0) {
 530         goto fail;
 531     }
 532
 533     reopen_fd_to_null(STDIN_FILENO);
 534     reopen_fd_to_null(STDOUT_FILENO);
 535     reopen_fd_to_null(STDERR_FILENO);
 536     return;
 537
 538 fail:
 539     if (pidfile) {
 540         unlink(pidfile);
 541     }
 542     g_critical("failed to daemonize");
 543     exit(EXIT_FAILURE);
 544 #endif
 545 }
 546
 547 static int send_response(GAState *s, QDict *payload)
 548 {
 549     const char *buf;
 550     QString *payload_qstr, *response_qstr;
 551     GIOStatus status;
 552
 553     g_assert(payload && s->channel);
 554
 555     payload_qstr = qobject_to_json(QOBJECT(payload));
 556     if (!payload_qstr) {
 557         return -EINVAL;
 558     }
 559
 560     if (s->delimit_response) {
 561         s->delimit_response = false;
 562         response_qstr = qstring_new();
 563         qstring_append_chr(response_qstr, QGA_SENTINEL_BYTE);
 564         qstring_append(response_qstr, qstring_get_str(payload_qstr));
 565         qobject_unref(payload_qstr);
 566     } else {
 567         response_qstr = payload_qstr;
 568     }
 569
 570     qstring_append_chr(response_qstr, '\n');
 571     buf = qstring_get_str(response_qstr);
 572     status = ga_channel_write_all(s->channel, buf, strlen(buf));
 573     qobject_unref(response_qstr);
 574     if (status != G_IO_STATUS_NORMAL) {
 575         return -EIO;
 576     }
 577
 578     return 0;
 579 }
 580
 581 static void process_command(GAState *s, QDict *req)
 582 {
 583     QDict *rsp;
 584     int ret;
 585
 586     g_assert(req);
 587     g_debug("processing command");
 588     rsp = qmp_dispatch(&ga_commands, QOBJECT(req), false);
 589     if (rsp) {
 590         ret = send_response(s, rsp);
 591         if (ret < 0) {
 592             g_warning("error sending response: %s", strerror(-ret));
 593         }
 594         qobject_unref(rsp);
 595     }
 596 }
 597
 598 /* handle requests/control events coming in over the channel */
 599 static void process_event(void *opaque, QObject *obj, Error *err)
 600 {
 601     GAState *s = opaque;
 602     QDict *req, *rsp;
 603     int ret;
 604
 605     g_debug("process_event: called");
 606     assert(!obj != !err);
 607     if (err) {
 608         goto err;
 609     }
 610     req = qobject_to(QDict, obj);
 611     if (!req) {
 612         error_setg(&err, "Input must be a JSON object");
 613         goto err;
 614     }
 615     if (!qdict_haskey(req, "execute")) {
 616         g_warning("unrecognized payload format");
 617         error_setg(&err, QERR_UNSUPPORTED);
 618         goto err;
 619     }
 620
 621     process_command(s, req);
 622     qobject_unref(obj);
 623     return;
 624
 625 err:
 626     g_warning("failed to parse event: %s", error_get_pretty(err));
 627     rsp = qmp_error_response(err);
 628     ret = send_response(s, rsp);
 629     if (ret < 0) {
 630         g_warning("error sending error response: %s", strerror(-ret));
 631     }
 632     qobject_unref(rsp);
 633     qobject_unref(obj);
 634 }
 635
 636 /* false return signals GAChannel to close the current client connection */
 637 static gboolean channel_event_cb(GIOCondition condition, gpointer data)
 638 {
 639     GAState *s = data;
 640     gchar buf[QGA_READ_COUNT_DEFAULT+1];
 641     gsize count;
 642     GIOStatus status = ga_channel_read(s->channel, buf, QGA_READ_COUNT_DEFAULT, &count);
 643     switch (status) {
 644     case G_IO_STATUS_ERROR:
 645         g_warning("error reading channel");
 646         return false;
 647     case G_IO_STATUS_NORMAL:
 648         buf[count] = 0;
 649         g_debug("read data, count: %d, data: %s", (int)count, buf);
 650         json_message_parser_feed(&s->parser, (char *)buf, (int)count);
 651         break;
 652     case G_IO_STATUS_EOF:
 653         g_debug("received EOF");
 654         if (!s->virtio) {
 655             return false;
 656         }
 657         /* fall through */
 658     case G_IO_STATUS_AGAIN:
 659         /* virtio causes us to spin here when no process is attached to
 660          * host-side chardev. sleep a bit to mitigate this
 661          */
 662         if (s->virtio) {
 663             usleep(100*1000);
 664         }
 665         return true;
 666     default:
 667         g_warning("unknown channel read status, closing");
 668         return false;
 669     }
 670     return true;
 671 }
 672
 673 static gboolean channel_init(GAState *s, const gchar *method, const gchar *path,
 674                              int listen_fd)
 675 {
 676     GAChannelMethod channel_method;
 677
 678     if (strcmp(method, "virtio-serial") == 0) {
 679         s->virtio = true; /* virtio requires special handling in some cases */
 680         channel_method = GA_CHANNEL_VIRTIO_SERIAL;
 681     } else if (strcmp(method, "isa-serial") == 0) {
 682         channel_method = GA_CHANNEL_ISA_SERIAL;
 683     } else if (strcmp(method, "unix-listen") == 0) {
 684         channel_method = GA_CHANNEL_UNIX_LISTEN;
 685     } else if (strcmp(method, "vsock-listen") == 0) {
 686         channel_method = GA_CHANNEL_VSOCK_LISTEN;
 687     } else {
 688         g_critical("unsupported channel method/type: %s", method);
 689         return false;
 690     }
 691
 692     s->channel = ga_channel_new(channel_method, path, listen_fd,
 693                                 channel_event_cb, s);
 694     if (!s->channel) {
 695         g_critical("failed to create guest agent channel");
 696         return false;
 697     }
 698
 699     return true;
 700 }
 701
 702 #ifdef _WIN32
 703 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
 704                                   LPVOID ctx)
 705 {
 706     DWORD ret = NO_ERROR;
 707     GAService *service = &ga_state->service;
 708
 709     switch (ctrl)
 710     {
 711         case SERVICE_CONTROL_STOP:
 712         case SERVICE_CONTROL_SHUTDOWN:
 713             quit_handler(SIGTERM);
 714             service->status.dwCurrentState = SERVICE_STOP_PENDING;
 715             SetServiceStatus(service->status_handle, &service->status);
 716             break;
 717
 718         default:
 719             ret = ERROR_CALL_NOT_IMPLEMENTED;
 720     }
 721     return ret;
 722 }
 723
 724 VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
 725 {
 726     GAService *service = &ga_state->service;
 727
 728     service->status_handle = RegisterServiceCtrlHandlerEx(QGA_SERVICE_NAME,
 729         service_ctrl_handler, NULL);
 730
 731     if (service->status_handle == 0) {
 732         g_critical("Failed to register extended requests function!\n");
 733         return;
 734     }
 735
 736     service->status.dwServiceType = SERVICE_WIN32;
 737     service->status.dwCurrentState = SERVICE_RUNNING;
 738     service->status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 739     service->status.dwWin32ExitCode = NO_ERROR;
 740     service->status.dwServiceSpecificExitCode = NO_ERROR;
 741     service->status.dwCheckPoint = 0;
 742     service->status.dwWaitHint = 0;
 743     SetServiceStatus(service->status_handle, &service->status);
 744
 745     g_main_loop_run(ga_state->main_loop);
 746
 747     service->status.dwCurrentState = SERVICE_STOPPED;
 748     SetServiceStatus(service->status_handle, &service->status);
 749 }
 750 #endif
 751
 752 static void set_persistent_state_defaults(GAPersistentState *pstate)
 753 {
 754     g_assert(pstate);
 755     pstate->fd_counter = QGA_PSTATE_DEFAULT_FD_COUNTER;
 756 }
 757
 758 static void persistent_state_from_keyfile(GAPersistentState *pstate,
 759                                           GKeyFile *keyfile)
 760 {
 761     g_assert(pstate);
 762     g_assert(keyfile);
 763     /* if any fields are missing, either because the file was tampered with
 764      * by agents of chaos, or because the field wasn't present at the time the
 765      * file was created, the best we can ever do is start over with the default
 766      * values. so load them now, and ignore any errors in accessing key-value
 767      * pairs
 768      */
 769     set_persistent_state_defaults(pstate);
 770
 771     if (g_key_file_has_key(keyfile, "global", "fd_counter", NULL)) {
 772         pstate->fd_counter =
 773             g_key_file_get_integer(keyfile, "global", "fd_counter", NULL);
 774     }
 775 }
 776
 777 static void persistent_state_to_keyfile(const GAPersistentState *pstate,
 778                                         GKeyFile *keyfile)
 779 {
 780     g_assert(pstate);
 781     g_assert(keyfile);
 782
 783     g_key_file_set_integer(keyfile, "global", "fd_counter", pstate->fd_counter);
 784 }
 785
 786 static gboolean write_persistent_state(const GAPersistentState *pstate,
 787                                        const gchar *path)
 788 {
 789     GKeyFile *keyfile = g_key_file_new();
 790     GError *gerr = NULL;
 791     gboolean ret = true;
 792     gchar *data = NULL;
 793     gsize data_len;
 794
 795     g_assert(pstate);
 796
 797     persistent_state_to_keyfile(pstate, keyfile);
 798     data = g_key_file_to_data(keyfile, &data_len, &gerr);
 799     if (gerr) {
 800         g_critical("failed to convert persistent state to string: %s",
 801                    gerr->message);
 802         ret = false;
 803         goto out;
 804     }
 805
 806     g_file_set_contents(path, data, data_len, &gerr);
 807     if (gerr) {
 808         g_critical("failed to write persistent state to %s: %s",
 809                     path, gerr->message);
 810         ret = false;
 811         goto out;
 812     }
 813
 814 out:
 815     if (gerr) {
 816         g_error_free(gerr);
 817     }
 818     if (keyfile) {
 819         g_key_file_free(keyfile);
 820     }
 821     g_free(data);
 822     return ret;
 823 }
 824
 825 static gboolean read_persistent_state(GAPersistentState *pstate,
 826                                       const gchar *path, gboolean frozen)
 827 {
 828     GKeyFile *keyfile = NULL;
 829     GError *gerr = NULL;
 830     struct stat st;
 831     gboolean ret = true;
 832
 833     g_assert(pstate);
 834
 835     if (stat(path, &st) == -1) {
 836         /* it's okay if state file doesn't exist, but any other error
 837          * indicates a permissions issue or some other misconfiguration
 838          * that we likely won't be able to recover from.
 839          */
 840         if (errno != ENOENT) {
 841             g_critical("unable to access state file at path %s: %s",
 842                        path, strerror(errno));
 843             ret = false;
 844             goto out;
 845         }
 846
 847         /* file doesn't exist. initialize state to default values and
 848          * attempt to save now. (we could wait till later when we have
 849          * modified state we need to commit, but if there's a problem,
 850          * such as a missing parent directory, we want to catch it now)
 851          *
 852          * there is a potential scenario where someone either managed to
 853          * update the agent from a version that didn't use a key store
 854          * while qemu-ga thought the filesystem was frozen, or
 855          * deleted the key store prior to issuing a fsfreeze, prior
 856          * to restarting the agent. in this case we go ahead and defer
 857          * initial creation till we actually have modified state to
 858          * write, otherwise fail to recover from freeze.
 859          */
 860         set_persistent_state_defaults(pstate);
 861         if (!frozen) {
 862             ret = write_persistent_state(pstate, path);
 863             if (!ret) {
 864                 g_critical("unable to create state file at path %s", path);
 865                 ret = false;
 866                 goto out;
 867             }
 868         }
 869         ret = true;
 870         goto out;
 871     }
 872
 873     keyfile = g_key_file_new();
 874     g_key_file_load_from_file(keyfile, path, 0, &gerr);
 875     if (gerr) {
 876         g_critical("error loading persistent state from path: %s, %s",
 877                    path, gerr->message);
 878         ret = false;
 879         goto out;
 880     }
 881
 882     persistent_state_from_keyfile(pstate, keyfile);
 883
 884 out:
 885     if (keyfile) {
 886         g_key_file_free(keyfile);
 887     }
 888     if (gerr) {
 889         g_error_free(gerr);
 890     }
 891
 892     return ret;
 893 }
 894
 895 int64_t ga_get_fd_handle(GAState *s, Error **errp)
 896 {
 897     int64_t handle;
 898
 899     g_assert(s->pstate_filepath);
 900     /* we blacklist commands and avoid operations that potentially require
 901      * writing to disk when we're in a frozen state. this includes opening
 902      * new files, so we should never get here in that situation
 903      */
 904     g_assert(!ga_is_frozen(s));
 905
 906     handle = s->pstate.fd_counter++;
 907
 908     /* This should never happen on a reasonable timeframe, as guest-file-open
 909      * would have to be issued 2^63 times */
 910     if (s->pstate.fd_counter == INT64_MAX) {
 911         abort();
 912     }
 913
 914     if (!write_persistent_state(&s->pstate, s->pstate_filepath)) {
 915         error_setg(errp, "failed to commit persistent state to disk");
 916         return -1;
 917     }
 918
 919     return handle;
 920 }
 921
 922 static void ga_print_cmd(QmpCommand *cmd, void *opaque)
 923 {
 924     printf("%s\n", qmp_command_name(cmd));
 925 }
 926
 927 static GList *split_list(const gchar *str, const gchar *delim)
 928 {
 929     GList *list = NULL;
 930     int i;
 931     gchar **strv;
 932
 933     strv = g_strsplit(str, delim, -1);
 934     for (i = 0; strv[i]; i++) {
 935         list = g_list_prepend(list, strv[i]);
 936     }
 937     g_free(strv);
 938
 939     return list;
 940 }
 941
 942 typedef struct GAConfig {
 943     char *channel_path;
 944     char *method;
 945     char *log_filepath;
 946     char *pid_filepath;
 947 #ifdef CONFIG_FSFREEZE
 948     char *fsfreeze_hook;
 949 #endif
 950     char *state_dir;
 951 #ifdef _WIN32
 952     const char *service;
 953 #endif
 954     gchar *bliststr; /* blacklist may point to this string */
 955     GList *blacklist;
 956     int daemonize;
 957     GLogLevelFlags log_level;
 958     int dumpconf;
 959 } GAConfig;
 960
 961 static void config_load(GAConfig *config)
 962 {
 963     GError *gerr = NULL;
 964     GKeyFile *keyfile;
 965     const char *conf = g_getenv("QGA_CONF") ?: QGA_CONF_DEFAULT;
 966
 967     /* read system config */
 968     keyfile = g_key_file_new();
 969     if (!g_key_file_load_from_file(keyfile, conf, 0, &gerr)) {
 970         goto end;
 971     }
 972     if (g_key_file_has_key(keyfile, "general", "daemon", NULL)) {
 973         config->daemonize =
 974             g_key_file_get_boolean(keyfile, "general", "daemon", &gerr);
 975     }
 976     if (g_key_file_has_key(keyfile, "general", "method", NULL)) {
 977         config->method =
 978             g_key_file_get_string(keyfile, "general", "method", &gerr);
 979     }
 980     if (g_key_file_has_key(keyfile, "general", "path", NULL)) {
 981         config->channel_path =
 982             g_key_file_get_string(keyfile, "general", "path", &gerr);
 983     }
 984     if (g_key_file_has_key(keyfile, "general", "logfile", NULL)) {
 985         config->log_filepath =
 986             g_key_file_get_string(keyfile, "general", "logfile", &gerr);
 987     }
 988     if (g_key_file_has_key(keyfile, "general", "pidfile", NULL)) {
 989         config->pid_filepath =
 990             g_key_file_get_string(keyfile, "general", "pidfile", &gerr);
 991     }
 992 #ifdef CONFIG_FSFREEZE
 993     if (g_key_file_has_key(keyfile, "general", "fsfreeze-hook", NULL)) {
 994         config->fsfreeze_hook =
 995             g_key_file_get_string(keyfile,
 996                                   "general", "fsfreeze-hook", &gerr);
 997     }
 998 #endif
 999     if (g_key_file_has_key(keyfile, "general", "statedir", NULL)) {
1000         config->state_dir =
1001             g_key_file_get_string(keyfile, "general", "statedir", &gerr);
1002     }
1003     if (g_key_file_has_key(keyfile, "general", "verbose", NULL) &&
1004         g_key_file_get_boolean(keyfile, "general", "verbose", &gerr)) {
1005         /* enable all log levels */
1006         config->log_level = G_LOG_LEVEL_MASK;
1007     }
1008     if (g_key_file_has_key(keyfile, "general", "blacklist", NULL)) {
1009         config->bliststr =
1010             g_key_file_get_string(keyfile, "general", "blacklist", &gerr);
1011         config->blacklist = g_list_concat(config->blacklist,
1012                                           split_list(config->bliststr, ","));
1013     }
1014
1015 end:
1016     g_key_file_free(keyfile);
1017     if (gerr &&
1018         !(gerr->domain == G_FILE_ERROR && gerr->code == G_FILE_ERROR_NOENT)) {
1019         g_critical("error loading configuration from path: %s, %s",
1020                    QGA_CONF_DEFAULT, gerr->message);
1021         exit(EXIT_FAILURE);
1022     }
1023     g_clear_error(&gerr);
1024 }
1025
1026 static gchar *list_join(GList *list, const gchar separator)
1027 {
1028     GString *str = g_string_new("");
1029
1030     while (list) {
1031         str = g_string_append(str, (gchar *)list->data);
1032         list = g_list_next(list);
1033         if (list) {
1034             str = g_string_append_c(str, separator);
1035         }
1036     }
1037
1038     return g_string_free(str, FALSE);
1039 }
1040
1041 static void config_dump(GAConfig *config)
1042 {
1043     GError *error = NULL;
1044     GKeyFile *keyfile;
1045     gchar *tmp;
1046
1047     keyfile = g_key_file_new();
1048     g_assert(keyfile);
1049
1050     g_key_file_set_boolean(keyfile, "general", "daemon", config->daemonize);
1051     g_key_file_set_string(keyfile, "general", "method", config->method);
1052     if (config->channel_path) {
1053         g_key_file_set_string(keyfile, "general", "path", config->channel_path);
1054     }
1055     if (config->log_filepath) {
1056         g_key_file_set_string(keyfile, "general", "logfile",
1057                               config->log_filepath);
1058     }
1059     g_key_file_set_string(keyfile, "general", "pidfile", config->pid_filepath);
1060 #ifdef CONFIG_FSFREEZE
1061     if (config->fsfreeze_hook) {
1062         g_key_file_set_string(keyfile, "general", "fsfreeze-hook",
1063                               config->fsfreeze_hook);
1064     }
1065 #endif
1066     g_key_file_set_string(keyfile, "general", "statedir", config->state_dir);
1067     g_key_file_set_boolean(keyfile, "general", "verbose",
1068                            config->log_level == G_LOG_LEVEL_MASK);
1069     tmp = list_join(config->blacklist, ',');
1070     g_key_file_set_string(keyfile, "general", "blacklist", tmp);
1071     g_free(tmp);
1072
1073     tmp = g_key_file_to_data(keyfile, NULL, &error);
1074     if (error) {
1075         g_critical("Failed to dump keyfile: %s", error->message);
1076         g_clear_error(&error);
1077     } else {
1078         printf("%s", tmp);
1079     }
1080
1081     g_free(tmp);
1082     g_key_file_free(keyfile);
1083 }
1084
1085 static void config_parse(GAConfig *config, int argc, char **argv)
1086 {
1087     const char *sopt = "hVvdm:p:l:f:F::b:s:t:D";
1088     int opt_ind = 0, ch;
1089     const struct option lopt[] = {
1090         { "help", 0, NULL, 'h' },
1091         { "version", 0, NULL, 'V' },
1092         { "dump-conf", 0, NULL, 'D' },
1093         { "logfile", 1, NULL, 'l' },
1094         { "pidfile", 1, NULL, 'f' },
1095 #ifdef CONFIG_FSFREEZE
1096         { "fsfreeze-hook", 2, NULL, 'F' },
1097 #endif
1098         { "verbose", 0, NULL, 'v' },
1099         { "method", 1, NULL, 'm' },
1100         { "path", 1, NULL, 'p' },
1101         { "daemonize", 0, NULL, 'd' },
1102         { "blacklist", 1, NULL, 'b' },
1103 #ifdef _WIN32
1104         { "service", 1, NULL, 's' },
1105 #endif
1106         { "statedir", 1, NULL, 't' },
1107         { NULL, 0, NULL, 0 }
1108     };
1109
1110     while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
1111         switch (ch) {
1112         case 'm':
1113             g_free(config->method);
1114             config->method = g_strdup(optarg);
1115             break;
1116         case 'p':
1117             g_free(config->channel_path);
1118             config->channel_path = g_strdup(optarg);
1119             break;
1120         case 'l':
1121             g_free(config->log_filepath);
1122             config->log_filepath = g_strdup(optarg);
1123             break;
1124         case 'f':
1125             g_free(config->pid_filepath);
1126             config->pid_filepath = g_strdup(optarg);
1127             break;
1128 #ifdef CONFIG_FSFREEZE
1129         case 'F':
1130             g_free(config->fsfreeze_hook);
1131             config->fsfreeze_hook = g_strdup(optarg ?: QGA_FSFREEZE_HOOK_DEFAULT);
1132             break;
1133 #endif
1134         case 't':
1135             g_free(config->state_dir);
1136             config->state_dir = g_strdup(optarg);
1137             break;
1138         case 'v':
1139             /* enable all log levels */
1140             config->log_level = G_LOG_LEVEL_MASK;
1141             break;
1142         case 'V':
1143             printf("QEMU Guest Agent %s\n", QEMU_VERSION);
1144             exit(EXIT_SUCCESS);
1145         case 'd':
1146             config->daemonize = 1;
1147             break;
1148         case 'D':
1149             config->dumpconf = 1;
1150             break;
1151         case 'b': {
1152             if (is_help_option(optarg)) {
1153                 qmp_for_each_command(&ga_commands, ga_print_cmd, NULL);
1154                 exit(EXIT_SUCCESS);
1155             }
1156             config->blacklist = g_list_concat(config->blacklist,
1157                                              split_list(optarg, ","));
1158             break;
1159         }
1160 #ifdef _WIN32
1161         case 's':
1162             config->service = optarg;
1163             if (strcmp(config->service, "install") == 0) {
1164                 if (ga_install_vss_provider()) {
1165                     exit(EXIT_FAILURE);
1166                 }
1167                 if (ga_install_service(config->channel_path,
1168                                        config->log_filepath, config->state_dir)) {
1169                     exit(EXIT_FAILURE);
1170                 }
1171                 exit(EXIT_SUCCESS);
1172             } else if (strcmp(config->service, "uninstall") == 0) {
1173                 ga_uninstall_vss_provider();
1174                 exit(ga_uninstall_service());
1175             } else if (strcmp(config->service, "vss-install") == 0) {
1176                 if (ga_install_vss_provider()) {
1177                     exit(EXIT_FAILURE);
1178                 }
1179                 exit(EXIT_SUCCESS);
1180             } else if (strcmp(config->service, "vss-uninstall") == 0) {
1181                 ga_uninstall_vss_provider();
1182                 exit(EXIT_SUCCESS);
1183             } else {
1184                 printf("Unknown service command.\n");
1185                 exit(EXIT_FAILURE);
1186             }
1187             break;
1188 #endif
1189         case 'h':
1190             usage(argv[0]);
1191             exit(EXIT_SUCCESS);
1192         case '?':
1193             g_print("Unknown option, try '%s --help' for more information.\n",
1194                     argv[0]);
1195             exit(EXIT_FAILURE);
1196         }
1197     }
1198 }
1199
1200 static void config_free(GAConfig *config)
1201 {
1202     g_free(config->method);
1203     g_free(config->log_filepath);
1204     g_free(config->pid_filepath);
1205     g_free(config->state_dir);
1206     g_free(config->channel_path);
1207     g_free(config->bliststr);
1208 #ifdef CONFIG_FSFREEZE
1209     g_free(config->fsfreeze_hook);
1210 #endif
1211     g_list_free_full(config->blacklist, g_free);
1212     g_free(config);
1213 }
1214
1215 static bool check_is_frozen(GAState *s)
1216 {
1217 #ifndef _WIN32
1218     /* check if a previous instance of qemu-ga exited with filesystems' state
1219      * marked as frozen. this could be a stale value (a non-qemu-ga process
1220      * or reboot may have since unfrozen them), but better to require an
1221      * uneeded unfreeze than to risk hanging on start-up
1222      */
1223     struct stat st;
1224     if (stat(s->state_filepath_isfrozen, &st) == -1) {
1225         /* it's okay if the file doesn't exist, but if we can't access for
1226          * some other reason, such as permissions, there's a configuration
1227          * that needs to be addressed. so just bail now before we get into
1228          * more trouble later
1229          */
1230         if (errno != ENOENT) {
1231             g_critical("unable to access state file at path %s: %s",
1232                        s->state_filepath_isfrozen, strerror(errno));
1233             return EXIT_FAILURE;
1234         }
1235     } else {
1236         g_warning("previous instance appears to have exited with frozen"
1237                   " filesystems. deferring logging/pidfile creation and"
1238                   " disabling non-fsfreeze-safe commands until"
1239                   " guest-fsfreeze-thaw is issued, or filesystems are"
1240                   " manually unfrozen and the file %s is removed",
1241                   s->state_filepath_isfrozen);
1242         return true;
1243     }
1244 #endif
1245     return false;
1246 }
1247
1248 static int run_agent(GAState *s, GAConfig *config, int socket_activation)
1249 {
1250     ga_state = s;
1251
1252     g_log_set_default_handler(ga_log, s);
1253     g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
1254     ga_enable_logging(s);
1255
1256 #ifdef _WIN32
1257     /* On win32 the state directory is application specific (be it the default
1258      * or a user override). We got past the command line parsing; let's create
1259      * the directory (with any intermediate directories). If we run into an
1260      * error later on, we won't try to clean up the directory, it is considered
1261      * persistent.
1262      */
1263     if (g_mkdir_with_parents(config->state_dir, S_IRWXU) == -1) {
1264         g_critical("unable to create (an ancestor of) the state directory"
1265                    " '%s': %s", config->state_dir, strerror(errno));
1266         return EXIT_FAILURE;
1267     }
1268 #endif
1269
1270     if (ga_is_frozen(s)) {
1271         if (config->daemonize) {
1272             /* delay opening/locking of pidfile till filesystems are unfrozen */
1273             s->deferred_options.pid_filepath = config->pid_filepath;
1274             become_daemon(NULL);
1275         }
1276         if (config->log_filepath) {
1277             /* delay opening the log file till filesystems are unfrozen */
1278             s->deferred_options.log_filepath = config->log_filepath;
1279         }
1280         ga_disable_logging(s);
1281         qmp_for_each_command(&ga_commands, ga_disable_non_whitelisted, NULL);
1282     } else {
1283         if (config->daemonize) {
1284             become_daemon(config->pid_filepath);
1285         }
1286         if (config->log_filepath) {
1287             FILE *log_file = ga_open_logfile(config->log_filepath);
1288             if (!log_file) {
1289                 g_critical("unable to open specified log file: %s",
1290                            strerror(errno));
1291                 return EXIT_FAILURE;
1292             }
1293             s->log_file = log_file;
1294         }
1295     }
1296
1297     /* load persistent state from disk */
1298     if (!read_persistent_state(&s->pstate,
1299                                s->pstate_filepath,
1300                                ga_is_frozen(s))) {
1301         g_critical("failed to load persistent state");
1302         return EXIT_FAILURE;
1303     }
1304
1305     config->blacklist = ga_command_blacklist_init(config->blacklist);
1306     if (config->blacklist) {
1307         GList *l = config->blacklist;
1308         s->blacklist = config->blacklist;
1309         do {
1310             g_debug("disabling command: %s", (char *)l->data);
1311             qmp_disable_command(&ga_commands, l->data);
1312             l = g_list_next(l);
1313         } while (l);
1314     }
1315     s->command_state = ga_command_state_new();
1316     ga_command_state_init(s, s->command_state);
1317     ga_command_state_init_all(s->command_state);
1318     json_message_parser_init(&s->parser, process_event, s, NULL);
1319
1320 #ifndef _WIN32
1321     if (!register_signal_handlers()) {
1322         g_critical("failed to register signal handlers");
1323         return EXIT_FAILURE;
1324     }
1325 #endif
1326
1327     s->main_loop = g_main_loop_new(NULL, false);
1328
1329     if (!channel_init(ga_state, config->method, config->channel_path,
1330                       socket_activation ? FIRST_SOCKET_ACTIVATION_FD : -1)) {
1331         g_critical("failed to initialize guest agent channel");
1332         return EXIT_FAILURE;
1333     }
1334 #ifndef _WIN32
1335     g_main_loop_run(ga_state->main_loop);
1336 #else
1337     if (config->daemonize) {
1338         SERVICE_TABLE_ENTRY service_table[] = {
1339             { (char *)QGA_SERVICE_NAME, service_main }, { NULL, NULL } };
1340         StartServiceCtrlDispatcher(service_table);
1341     } else {
1342         g_main_loop_run(ga_state->main_loop);
1343     }
1344 #endif
1345
1346     return EXIT_SUCCESS;
1347 }
1348
1349 int main(int argc, char **argv)
1350 {
1351     int ret = EXIT_SUCCESS;
1352     GAState *s = g_new0(GAState, 1);
1353     GAConfig *config = g_new0(GAConfig, 1);
1354     int socket_activation;
1355
1356     config->log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
1357
1358     qga_qmp_init_marshal(&ga_commands);
1359
1360     init_dfl_pathnames();
1361     config_load(config);
1362     config_parse(config, argc, argv);
1363
1364     if (config->pid_filepath == NULL) {
1365         config->pid_filepath = g_strdup(dfl_pathnames.pidfile);
1366     }
1367
1368     if (config->state_dir == NULL) {
1369         config->state_dir = g_strdup(dfl_pathnames.state_dir);
1370     }
1371
1372     if (config->method == NULL) {
1373         config->method = g_strdup("virtio-serial");
1374     }
1375
1376     socket_activation = check_socket_activation();
1377     if (socket_activation > 1) {
1378         g_critical("qemu-ga only supports listening on one socket");
1379         ret = EXIT_FAILURE;
1380         goto end;
1381     }
1382     if (socket_activation) {
1383         SocketAddress *addr;
1384
1385         g_free(config->method);
1386         g_free(config->channel_path);
1387         config->method = NULL;
1388         config->channel_path = NULL;
1389
1390         addr = socket_local_address(FIRST_SOCKET_ACTIVATION_FD, NULL);
1391         if (addr) {
1392             if (addr->type == SOCKET_ADDRESS_TYPE_UNIX) {
1393                 config->method = g_strdup("unix-listen");
1394             } else if (addr->type == SOCKET_ADDRESS_TYPE_VSOCK) {
1395                 config->method = g_strdup("vsock-listen");
1396             }
1397
1398             qapi_free_SocketAddress(addr);
1399         }
1400
1401         if (!config->method) {
1402             g_critical("unsupported listen fd type");
1403             ret = EXIT_FAILURE;
1404             goto end;
1405         }
1406     } else if (config->channel_path == NULL) {
1407         if (strcmp(config->method, "virtio-serial") == 0) {
1408             /* try the default path for the virtio-serial port */
1409             config->channel_path = g_strdup(QGA_VIRTIO_PATH_DEFAULT);
1410         } else if (strcmp(config->method, "isa-serial") == 0) {
1411             /* try the default path for the serial port - COM1 */
1412             config->channel_path = g_strdup(QGA_SERIAL_PATH_DEFAULT);
1413         } else {
1414             g_critical("must specify a path for this channel");
1415             ret = EXIT_FAILURE;
1416             goto end;
1417         }
1418     }
1419
1420     s->log_level = config->log_level;
1421     s->log_file = stderr;
1422 #ifdef CONFIG_FSFREEZE
1423     s->fsfreeze_hook = config->fsfreeze_hook;
1424 #endif
1425     s->pstate_filepath = g_strdup_printf("%s/qga.state", config->state_dir);
1426     s->state_filepath_isfrozen = g_strdup_printf("%s/qga.state.isfrozen",
1427                                                  config->state_dir);
1428     s->frozen = check_is_frozen(s);
1429
1430     if (config->dumpconf) {
1431         config_dump(config);
1432         goto end;
1433     }
1434
1435     ret = run_agent(s, config, socket_activation);
1436
1437 end:
1438     if (s->command_state) {
1439         ga_command_state_cleanup_all(s->command_state);
1440         ga_command_state_free(s->command_state);
1441         json_message_parser_destroy(&s->parser);
1442     }
1443     if (s->channel) {
1444         ga_channel_free(s->channel);
1445     }
1446     g_free(s->pstate_filepath);
1447     g_free(s->state_filepath_isfrozen);
1448
1449     if (config->daemonize) {
1450         unlink(config->pid_filepath);
1451     }
1452
1453     config_free(config);
1454     if (s->main_loop) {
1455         g_main_loop_unref(s->main_loop);
1456     }
1457     g_free(s);
1458
1459     return ret;
1460 }