Example #1
0
void ga_unset_frozen(GAState *s)
{
    if (!ga_is_frozen(s)) {
        return;
    }

    /* if we delayed creation/opening of pid/log files due to being
     * in a frozen state at start up, do it now
     */
    if (s->deferred_options.log_filepath) {
        s->log_file = ga_open_logfile(s->deferred_options.log_filepath);
        if (!s->log_file) {
            s->log_file = stderr;
        }
        s->deferred_options.log_filepath = NULL;
    }
    ga_enable_logging(s);
    g_warning("logging re-enabled due to filesystem unfreeze");
    if (s->deferred_options.pid_filepath) {
        if (!ga_open_pidfile(s->deferred_options.pid_filepath)) {
            g_warning("failed to create/open pid file");
        }
        s->deferred_options.pid_filepath = NULL;
    }

    /* enable all disabled, non-blacklisted commands */
    qmp_for_each_command(&ga_commands, ga_enable_non_blacklisted, s->blacklist);
    s->frozen = false;
    if (!ga_delete_file(s->state_filepath_isfrozen)) {
        g_warning("unable to delete %s, fsfreeze may not function properly",
                  s->state_filepath_isfrozen);
    }
}
Example #2
0
int main(int argc, char **argv)
{
    const char *sopt = "hVvdm:p:l:f:F::b:s:t:";
    const char *method = NULL, *path = NULL;
    const char *log_filepath = NULL;
    const char *pid_filepath;
#ifdef CONFIG_FSFREEZE
    const char *fsfreeze_hook = NULL;
#endif
    const char *state_dir;
#ifdef _WIN32
    const char *service = NULL;
#endif
    const struct option lopt[] = {
        { "help", 0, NULL, 'h' },
        { "version", 0, NULL, 'V' },
        { "logfile", 1, NULL, 'l' },
        { "pidfile", 1, NULL, 'f' },
#ifdef CONFIG_FSFREEZE
        { "fsfreeze-hook", 2, NULL, 'F' },
#endif
        { "verbose", 0, NULL, 'v' },
        { "method", 1, NULL, 'm' },
        { "path", 1, NULL, 'p' },
        { "daemonize", 0, NULL, 'd' },
        { "blacklist", 1, NULL, 'b' },
#ifdef _WIN32
        { "service", 1, NULL, 's' },
#endif
        { "statedir", 1, NULL, 't' },
        { NULL, 0, NULL, 0 }
    };
    int opt_ind = 0, ch, daemonize = 0, i, j, len;
    GLogLevelFlags log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
    GList *blacklist = NULL;
    GAState *s;

    module_call_init(MODULE_INIT_QAPI);

    init_dfl_pathnames();
    pid_filepath = dfl_pathnames.pidfile;
    state_dir = dfl_pathnames.state_dir;

    while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
        switch (ch) {
        case 'm':
            method = optarg;
            break;
        case 'p':
            path = optarg;
            break;
        case 'l':
            log_filepath = optarg;
            break;
        case 'f':
            pid_filepath = optarg;
            break;
#ifdef CONFIG_FSFREEZE
        case 'F':
            fsfreeze_hook = optarg ? optarg : QGA_FSFREEZE_HOOK_DEFAULT;
            break;
#endif
        case 't':
             state_dir = optarg;
             break;
        case 'v':
            /* enable all log levels */
            log_level = G_LOG_LEVEL_MASK;
            break;
        case 'V':
            printf("QEMU Guest Agent %s\n", QEMU_VERSION);
            return 0;
        case 'd':
            daemonize = 1;
            break;
        case 'b': {
            if (is_help_option(optarg)) {
                qmp_for_each_command(ga_print_cmd, NULL);
                return 0;
            }
            for (j = 0, i = 0, len = strlen(optarg); i < len; i++) {
                if (optarg[i] == ',') {
                    optarg[i] = 0;
                    blacklist = g_list_append(blacklist, &optarg[j]);
                    j = i + 1;
                }
            }
            if (j < i) {
                blacklist = g_list_append(blacklist, &optarg[j]);
            }
            break;
        }
#ifdef _WIN32
        case 's':
            service = optarg;
            if (strcmp(service, "install") == 0) {
                const char *fixed_state_dir;

                /* If the user passed the "-t" option, we save that state dir
                 * in the service. Otherwise we let the service fetch the state
                 * dir from the environment when it starts.
                 */
                fixed_state_dir = (state_dir == dfl_pathnames.state_dir) ?
                                  NULL :
                                  state_dir;
                if (ga_install_vss_provider()) {
                    return EXIT_FAILURE;
                }
                if (ga_install_service(path, log_filepath, fixed_state_dir)) {
                    return EXIT_FAILURE;
                }
                return 0;
            } else if (strcmp(service, "uninstall") == 0) {
                ga_uninstall_vss_provider();
                return ga_uninstall_service();
            } else {
                printf("Unknown service command.\n");
                return EXIT_FAILURE;
            }
            break;
#endif
        case 'h':
            usage(argv[0]);
            return 0;
        case '?':
            g_print("Unknown option, try '%s --help' for more information.\n",
                    argv[0]);
            return EXIT_FAILURE;
        }
    }

#ifdef _WIN32
    /* On win32 the state directory is application specific (be it the default
     * or a user override). We got past the command line parsing; let's create
     * the directory (with any intermediate directories). If we run into an
     * error later on, we won't try to clean up the directory, it is considered
     * persistent.
     */
    if (g_mkdir_with_parents(state_dir, S_IRWXU) == -1) {
        g_critical("unable to create (an ancestor of) the state directory"
                   " '%s': %s", state_dir, strerror(errno));
        return EXIT_FAILURE;
    }
#endif

    s = g_malloc0(sizeof(GAState));
    s->log_level = log_level;
    s->log_file = stderr;
#ifdef CONFIG_FSFREEZE
    s->fsfreeze_hook = fsfreeze_hook;
#endif
    g_log_set_default_handler(ga_log, s);
    g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
    ga_enable_logging(s);
    s->state_filepath_isfrozen = g_strdup_printf("%s/qga.state.isfrozen",
                                                 state_dir);
    s->pstate_filepath = g_strdup_printf("%s/qga.state", state_dir);
    s->frozen = false;

#ifndef _WIN32
    /* check if a previous instance of qemu-ga exited with filesystems' state
     * marked as frozen. this could be a stale value (a non-qemu-ga process
     * or reboot may have since unfrozen them), but better to require an
     * uneeded unfreeze than to risk hanging on start-up
     */
    struct stat st;
    if (stat(s->state_filepath_isfrozen, &st) == -1) {
        /* it's okay if the file doesn't exist, but if we can't access for
         * some other reason, such as permissions, there's a configuration
         * that needs to be addressed. so just bail now before we get into
         * more trouble later
         */
        if (errno != ENOENT) {
            g_critical("unable to access state file at path %s: %s",
                       s->state_filepath_isfrozen, strerror(errno));
            return EXIT_FAILURE;
        }
    } else {
        g_warning("previous instance appears to have exited with frozen"
                  " filesystems. deferring logging/pidfile creation and"
                  " disabling non-fsfreeze-safe commands until"
                  " guest-fsfreeze-thaw is issued, or filesystems are"
                  " manually unfrozen and the file %s is removed",
                  s->state_filepath_isfrozen);
        s->frozen = true;
    }
#endif

    if (ga_is_frozen(s)) {
        if (daemonize) {
            /* delay opening/locking of pidfile till filesystems are unfrozen */
            s->deferred_options.pid_filepath = pid_filepath;
            become_daemon(NULL);
        }
        if (log_filepath) {
            /* delay opening the log file till filesystems are unfrozen */
            s->deferred_options.log_filepath = log_filepath;
        }
        ga_disable_logging(s);
        qmp_for_each_command(ga_disable_non_whitelisted, NULL);
    } else {
        if (daemonize) {
            become_daemon(pid_filepath);
        }
        if (log_filepath) {
            FILE *log_file = ga_open_logfile(log_filepath);
            if (!log_file) {
                g_critical("unable to open specified log file: %s",
                           strerror(errno));
                goto out_bad;
            }
            s->log_file = log_file;
        }
    }

    /* load persistent state from disk */
    if (!read_persistent_state(&s->pstate,
                               s->pstate_filepath,
                               ga_is_frozen(s))) {
        g_critical("failed to load persistent state");
        goto out_bad;
    }

    blacklist = ga_command_blacklist_init(blacklist);
    if (blacklist) {
        s->blacklist = blacklist;
        do {
            g_debug("disabling command: %s", (char *)blacklist->data);
            qmp_disable_command(blacklist->data);
            blacklist = g_list_next(blacklist);
        } while (blacklist);
    }
    s->command_state = ga_command_state_new();
    ga_command_state_init(s, s->command_state);
    ga_command_state_init_all(s->command_state);
    json_message_parser_init(&s->parser, process_event);
    ga_state = s;
#ifndef _WIN32
    if (!register_signal_handlers()) {
        g_critical("failed to register signal handlers");
        goto out_bad;
    }
#endif

    s->main_loop = g_main_loop_new(NULL, false);
    if (!channel_init(ga_state, method, path)) {
        g_critical("failed to initialize guest agent channel");
        goto out_bad;
    }
#ifndef _WIN32
    g_main_loop_run(ga_state->main_loop);
#else
    if (daemonize) {
        SERVICE_TABLE_ENTRY service_table[] = {
            { (char *)QGA_SERVICE_NAME, service_main }, { NULL, NULL } };
        StartServiceCtrlDispatcher(service_table);
    } else {
        g_main_loop_run(ga_state->main_loop);
    }
#endif

    ga_command_state_cleanup_all(ga_state->command_state);
    ga_channel_free(ga_state->channel);

    if (daemonize) {
        unlink(pid_filepath);
    }
    return 0;

out_bad:
    if (daemonize) {
        unlink(pid_filepath);
    }
    return EXIT_FAILURE;
}