4 * Copyright IBM Corp. 2011
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.
23 #include "json-streamer.h"
24 #include "json-parser.h"
27 #include "qga/guest-agent-core.h"
31 #include "error_int.h"
32 #include "qapi/qmp-core.h"
33 #include "qga/channel.h"
35 #include "qga/service-win32.h"
40 #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
42 #define QGA_VIRTIO_PATH_DEFAULT "\\\\.\\Global\\org.qemu.guest_agent.0"
44 #define QGA_PIDFILE_DEFAULT "/var/run/qemu-ga.pid"
45 #define QGA_STATEDIR_DEFAULT "/tmp"
46 #define QGA_SENTINEL_BYTE 0xFF
49 JSONMessageParser parser;
52 bool virtio; /* fastpath to check for virtio to deal with poll() quirks */
53 GACommandState *command_state;
54 GLogLevelFlags log_level;
60 bool delimit_response;
63 const char *state_filepath_isfrozen;
65 const char *log_filepath;
66 const char *pid_filepath;
70 struct GAState *ga_state;
72 /* commands that are safe to issue while filesystems are frozen */
73 static const char *ga_freeze_whitelist[] = {
77 "guest-fsfreeze-status",
78 "guest-fsfreeze-thaw",
83 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
85 VOID WINAPI service_main(DWORD argc, TCHAR *argv[]);
88 static void quit_handler(int sig)
90 /* if we're frozen, don't exit unless we're absolutely forced to,
91 * because it's basically impossible for graceful exit to complete
92 * unless all log/pid files are on unfreezable filesystems. there's
93 * also a very likely chance killing the agent before unfreezing
94 * the filesystems is a mistake (or will be viewed as one later).
96 if (ga_is_frozen(ga_state)) {
99 g_debug("received signal num %d, quitting", sig);
101 if (g_main_loop_is_running(ga_state->main_loop)) {
102 g_main_loop_quit(ga_state->main_loop);
107 static gboolean register_signal_handlers(void)
109 struct sigaction sigact;
112 memset(&sigact, 0, sizeof(struct sigaction));
113 sigact.sa_handler = quit_handler;
115 ret = sigaction(SIGINT, &sigact, NULL);
117 g_error("error configuring signal handler: %s", strerror(errno));
120 ret = sigaction(SIGTERM, &sigact, NULL);
122 g_error("error configuring signal handler: %s", strerror(errno));
129 /* TODO: use this in place of all post-fork() fclose(std*) callers */
130 void reopen_fd_to_null(int fd)
134 nullfd = open("/dev/null", O_RDWR);
147 static void usage(const char *cmd)
150 "Usage: %s [-m <method> -p <path>] [<options>]\n"
151 "QEMU Guest Agent %s\n"
153 " -m, --method transport method: one of unix-listen, virtio-serial, or\n"
154 " isa-serial (virtio-serial is the default)\n"
155 " -p, --path device/socket path (the default for virtio-serial is:\n"
157 " -l, --logfile set logfile path, logs to stderr by default\n"
158 " -f, --pidfile specify pidfile (default is %s)\n"
159 " -t, --statedir specify dir to store state information (absolute paths\n"
160 " only, default is %s)\n"
161 " -v, --verbose log extra debugging information\n"
162 " -V, --version print version information and exit\n"
163 " -d, --daemonize become a daemon\n"
165 " -s, --service service commands: install, uninstall\n"
167 " -b, --blacklist comma-separated list of RPCs to disable (no spaces, \"?\"\n"
168 " to list available RPCs)\n"
169 " -h, --help display this help and exit\n"
172 , cmd, QEMU_VERSION, QGA_VIRTIO_PATH_DEFAULT, QGA_PIDFILE_DEFAULT,
173 QGA_STATEDIR_DEFAULT);
176 static const char *ga_log_level_str(GLogLevelFlags level)
178 switch (level & G_LOG_LEVEL_MASK) {
179 case G_LOG_LEVEL_ERROR:
181 case G_LOG_LEVEL_CRITICAL:
183 case G_LOG_LEVEL_WARNING:
185 case G_LOG_LEVEL_MESSAGE:
187 case G_LOG_LEVEL_INFO:
189 case G_LOG_LEVEL_DEBUG:
196 bool ga_logging_enabled(GAState *s)
198 return s->logging_enabled;
201 void ga_disable_logging(GAState *s)
203 s->logging_enabled = false;
206 void ga_enable_logging(GAState *s)
208 s->logging_enabled = true;
211 static void ga_log(const gchar *domain, GLogLevelFlags level,
212 const gchar *msg, gpointer opaque)
216 const char *level_str = ga_log_level_str(level);
218 if (!ga_logging_enabled(s)) {
222 level &= G_LOG_LEVEL_MASK;
224 if (domain && strcmp(domain, "syslog") == 0) {
225 syslog(LOG_INFO, "%s: %s", level_str, msg);
226 } else if (level & s->log_level) {
228 if (level & s->log_level) {
230 g_get_current_time(&time);
232 "%lu.%lu: %s: %s\n", time.tv_sec, time.tv_usec, level_str, msg);
237 void ga_set_response_delimited(GAState *s)
239 s->delimit_response = true;
243 static bool ga_open_pidfile(const char *pidfile)
248 pidfd = open(pidfile, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR);
249 if (pidfd == -1 || lockf(pidfd, F_TLOCK, 0)) {
250 g_critical("Cannot lock pid file, %s", strerror(errno));
254 if (ftruncate(pidfd, 0) || lseek(pidfd, 0, SEEK_SET)) {
255 g_critical("Failed to truncate pid file");
258 sprintf(pidstr, "%d", getpid());
259 if (write(pidfd, pidstr, strlen(pidstr)) != strlen(pidstr)) {
260 g_critical("Failed to write pid file");
271 static bool ga_open_pidfile(const char *pidfile)
277 static gint ga_strcmp(gconstpointer str1, gconstpointer str2)
279 return strcmp(str1, str2);
282 /* disable commands that aren't safe for fsfreeze */
283 static void ga_disable_non_whitelisted(void)
285 char **list_head, **list;
289 list_head = list = qmp_get_command_list();
290 while (*list != NULL) {
293 while (ga_freeze_whitelist[i] != NULL) {
294 if (strcmp(*list, ga_freeze_whitelist[i]) == 0) {
300 g_debug("disabling command: %s", *list);
301 qmp_disable_command(*list);
309 /* [re-]enable all commands, except those explicitly blacklisted by user */
310 static void ga_enable_non_blacklisted(GList *blacklist)
312 char **list_head, **list;
314 list_head = list = qmp_get_command_list();
315 while (*list != NULL) {
316 if (g_list_find_custom(blacklist, *list, ga_strcmp) == NULL &&
317 !qmp_command_is_enabled(*list)) {
318 g_debug("enabling command: %s", *list);
319 qmp_enable_command(*list);
327 static bool ga_create_file(const char *path)
329 int fd = open(path, O_CREAT | O_WRONLY, S_IWUSR | S_IRUSR);
331 g_warning("unable to open/create file %s: %s", path, strerror(errno));
338 static bool ga_delete_file(const char *path)
340 int ret = unlink(path);
342 g_warning("unable to delete file: %s: %s", path, strerror(errno));
349 bool ga_is_frozen(GAState *s)
354 void ga_set_frozen(GAState *s)
356 if (ga_is_frozen(s)) {
359 /* disable all non-whitelisted (for frozen state) commands */
360 ga_disable_non_whitelisted();
361 g_warning("disabling logging due to filesystem freeze");
362 ga_disable_logging(s);
364 if (!ga_create_file(s->state_filepath_isfrozen)) {
365 g_warning("unable to create %s, fsfreeze may not function properly",
366 s->state_filepath_isfrozen);
370 void ga_unset_frozen(GAState *s)
372 if (!ga_is_frozen(s)) {
376 /* if we delayed creation/opening of pid/log files due to being
377 * in a frozen state at start up, do it now
379 if (s->deferred_options.log_filepath) {
380 s->log_file = fopen(s->deferred_options.log_filepath, "a");
382 s->log_file = stderr;
384 s->deferred_options.log_filepath = NULL;
386 ga_enable_logging(s);
387 g_warning("logging re-enabled due to filesystem unfreeze");
388 if (s->deferred_options.pid_filepath) {
389 if (!ga_open_pidfile(s->deferred_options.pid_filepath)) {
390 g_warning("failed to create/open pid file");
392 s->deferred_options.pid_filepath = NULL;
395 /* enable all disabled, non-blacklisted commands */
396 ga_enable_non_blacklisted(s->blacklist);
398 if (!ga_delete_file(s->state_filepath_isfrozen)) {
399 g_warning("unable to delete %s, fsfreeze may not function properly",
400 s->state_filepath_isfrozen);
404 static void become_daemon(const char *pidfile)
418 if (!ga_open_pidfile(pidfile)) {
419 g_critical("failed to create pidfile");
429 if ((chdir("/")) < 0) {
433 reopen_fd_to_null(STDIN_FILENO);
434 reopen_fd_to_null(STDOUT_FILENO);
435 reopen_fd_to_null(STDERR_FILENO);
440 g_critical("failed to daemonize");
445 static int send_response(GAState *s, QObject *payload)
448 QString *payload_qstr, *response_qstr;
451 g_assert(payload && s->channel);
453 payload_qstr = qobject_to_json(payload);
458 if (s->delimit_response) {
459 s->delimit_response = false;
460 response_qstr = qstring_new();
461 qstring_append_chr(response_qstr, QGA_SENTINEL_BYTE);
462 qstring_append(response_qstr, qstring_get_str(payload_qstr));
463 QDECREF(payload_qstr);
465 response_qstr = payload_qstr;
468 qstring_append_chr(response_qstr, '\n');
469 buf = qstring_get_str(response_qstr);
470 status = ga_channel_write_all(s->channel, buf, strlen(buf));
471 QDECREF(response_qstr);
472 if (status != G_IO_STATUS_NORMAL) {
479 static void process_command(GAState *s, QDict *req)
485 g_debug("processing command");
486 rsp = qmp_dispatch(QOBJECT(req));
488 ret = send_response(s, rsp);
490 g_warning("error sending response: %s", strerror(ret));
496 /* handle requests/control events coming in over the channel */
497 static void process_event(JSONMessageParser *parser, QList *tokens)
499 GAState *s = container_of(parser, GAState, parser);
505 g_assert(s && parser);
507 g_debug("process_event: called");
508 obj = json_parser_parse_err(tokens, NULL, &err);
509 if (err || !obj || qobject_type(obj) != QTYPE_QDICT) {
513 g_warning("failed to parse event: unknown error");
514 error_set(&err, QERR_JSON_PARSING);
516 g_warning("failed to parse event: %s", error_get_pretty(err));
518 qdict_put_obj(qdict, "error", error_get_qobject(err));
521 qdict = qobject_to_qdict(obj);
526 /* handle host->guest commands */
527 if (qdict_haskey(qdict, "execute")) {
528 process_command(s, qdict);
530 if (!qdict_haskey(qdict, "error")) {
533 g_warning("unrecognized payload format");
534 error_set(&err, QERR_UNSUPPORTED);
535 qdict_put_obj(qdict, "error", error_get_qobject(err));
538 ret = send_response(s, QOBJECT(qdict));
540 g_warning("error sending error response: %s", strerror(ret));
547 /* false return signals GAChannel to close the current client connection */
548 static gboolean channel_event_cb(GIOCondition condition, gpointer data)
551 gchar buf[QGA_READ_COUNT_DEFAULT+1];
554 GIOStatus status = ga_channel_read(s->channel, buf, QGA_READ_COUNT_DEFAULT, &count);
556 g_warning("error reading channel: %s", err->message);
561 case G_IO_STATUS_ERROR:
562 g_warning("error reading channel");
564 case G_IO_STATUS_NORMAL:
566 g_debug("read data, count: %d, data: %s", (int)count, buf);
567 json_message_parser_feed(&s->parser, (char *)buf, (int)count);
569 case G_IO_STATUS_EOF:
570 g_debug("received EOF");
574 case G_IO_STATUS_AGAIN:
575 /* virtio causes us to spin here when no process is attached to
576 * host-side chardev. sleep a bit to mitigate this
583 g_warning("unknown channel read status, closing");
589 static gboolean channel_init(GAState *s, const gchar *method, const gchar *path)
591 GAChannelMethod channel_method;
593 if (method == NULL) {
594 method = "virtio-serial";
598 if (strcmp(method, "virtio-serial") != 0) {
599 g_critical("must specify a path for this channel");
602 /* try the default path for the virtio-serial port */
603 path = QGA_VIRTIO_PATH_DEFAULT;
606 if (strcmp(method, "virtio-serial") == 0) {
607 s->virtio = true; /* virtio requires special handling in some cases */
608 channel_method = GA_CHANNEL_VIRTIO_SERIAL;
609 } else if (strcmp(method, "isa-serial") == 0) {
610 channel_method = GA_CHANNEL_ISA_SERIAL;
611 } else if (strcmp(method, "unix-listen") == 0) {
612 channel_method = GA_CHANNEL_UNIX_LISTEN;
614 g_critical("unsupported channel method/type: %s", method);
618 s->channel = ga_channel_new(channel_method, path, channel_event_cb, s);
620 g_critical("failed to create guest agent channel");
628 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
631 DWORD ret = NO_ERROR;
632 GAService *service = &ga_state->service;
636 case SERVICE_CONTROL_STOP:
637 case SERVICE_CONTROL_SHUTDOWN:
638 quit_handler(SIGTERM);
639 service->status.dwCurrentState = SERVICE_STOP_PENDING;
640 SetServiceStatus(service->status_handle, &service->status);
644 ret = ERROR_CALL_NOT_IMPLEMENTED;
649 VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
651 GAService *service = &ga_state->service;
653 service->status_handle = RegisterServiceCtrlHandlerEx(QGA_SERVICE_NAME,
654 service_ctrl_handler, NULL);
656 if (service->status_handle == 0) {
657 g_critical("Failed to register extended requests function!\n");
661 service->status.dwServiceType = SERVICE_WIN32;
662 service->status.dwCurrentState = SERVICE_RUNNING;
663 service->status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
664 service->status.dwWin32ExitCode = NO_ERROR;
665 service->status.dwServiceSpecificExitCode = NO_ERROR;
666 service->status.dwCheckPoint = 0;
667 service->status.dwWaitHint = 0;
668 SetServiceStatus(service->status_handle, &service->status);
670 g_main_loop_run(ga_state->main_loop);
672 service->status.dwCurrentState = SERVICE_STOPPED;
673 SetServiceStatus(service->status_handle, &service->status);
677 int main(int argc, char **argv)
679 const char *sopt = "hVvdm:p:l:f:b:s:t:";
680 const char *method = NULL, *path = NULL;
681 const char *log_filepath = NULL;
682 const char *pid_filepath = QGA_PIDFILE_DEFAULT;
683 const char *state_dir = QGA_STATEDIR_DEFAULT;
685 const char *service = NULL;
687 const struct option lopt[] = {
688 { "help", 0, NULL, 'h' },
689 { "version", 0, NULL, 'V' },
690 { "logfile", 1, NULL, 'l' },
691 { "pidfile", 1, NULL, 'f' },
692 { "verbose", 0, NULL, 'v' },
693 { "method", 1, NULL, 'm' },
694 { "path", 1, NULL, 'p' },
695 { "daemonize", 0, NULL, 'd' },
696 { "blacklist", 1, NULL, 'b' },
698 { "service", 1, NULL, 's' },
700 { "statedir", 1, NULL, 't' },
703 int opt_ind = 0, ch, daemonize = 0, i, j, len;
704 GLogLevelFlags log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
705 GList *blacklist = NULL;
708 module_call_init(MODULE_INIT_QAPI);
710 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
719 log_filepath = optarg;
722 pid_filepath = optarg;
728 /* enable all log levels */
729 log_level = G_LOG_LEVEL_MASK;
732 printf("QEMU Guest Agent %s\n", QEMU_VERSION);
738 char **list_head, **list;
739 if (*optarg == '?') {
740 list_head = list = qmp_get_command_list();
741 while (*list != NULL) {
742 printf("%s\n", *list);
749 for (j = 0, i = 0, len = strlen(optarg); i < len; i++) {
750 if (optarg[i] == ',') {
752 blacklist = g_list_append(blacklist, &optarg[j]);
757 blacklist = g_list_append(blacklist, &optarg[j]);
764 if (strcmp(service, "install") == 0) {
765 return ga_install_service(path, log_filepath);
766 } else if (strcmp(service, "uninstall") == 0) {
767 return ga_uninstall_service();
769 printf("Unknown service command.\n");
778 g_print("Unknown option, try '%s --help' for more information.\n",
784 s = g_malloc0(sizeof(GAState));
785 s->log_level = log_level;
786 s->log_file = stderr;
787 g_log_set_default_handler(ga_log, s);
788 g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
789 ga_enable_logging(s);
790 s->state_filepath_isfrozen = g_strdup_printf("%s/qga.state.isfrozen",
794 /* check if a previous instance of qemu-ga exited with filesystems' state
795 * marked as frozen. this could be a stale value (a non-qemu-ga process
796 * or reboot may have since unfrozen them), but better to require an
797 * uneeded unfreeze than to risk hanging on start-up
800 if (stat(s->state_filepath_isfrozen, &st) == -1) {
801 /* it's okay if the file doesn't exist, but if we can't access for
802 * some other reason, such as permissions, there's a configuration
803 * that needs to be addressed. so just bail now before we get into
806 if (errno != ENOENT) {
807 g_critical("unable to access state file at path %s: %s",
808 s->state_filepath_isfrozen, strerror(errno));
812 g_warning("previous instance appears to have exited with frozen"
813 " filesystems. deferring logging/pidfile creation and"
814 " disabling non-fsfreeze-safe commands until"
815 " guest-fsfreeze-thaw is issued, or filesystems are"
816 " manually unfrozen and the file %s is removed",
817 s->state_filepath_isfrozen);
822 if (ga_is_frozen(s)) {
824 /* delay opening/locking of pidfile till filesystem are unfrozen */
825 s->deferred_options.pid_filepath = pid_filepath;
829 /* delay opening the log file till filesystems are unfrozen */
830 s->deferred_options.log_filepath = log_filepath;
832 ga_disable_logging(s);
833 ga_disable_non_whitelisted();
836 become_daemon(pid_filepath);
839 FILE *log_file = fopen(log_filepath, "a");
841 g_critical("unable to open specified log file: %s",
845 s->log_file = log_file;
850 s->blacklist = blacklist;
852 g_debug("disabling command: %s", (char *)blacklist->data);
853 qmp_disable_command(blacklist->data);
854 blacklist = g_list_next(blacklist);
857 s->command_state = ga_command_state_new();
858 ga_command_state_init(s, s->command_state);
859 ga_command_state_init_all(s->command_state);
860 json_message_parser_init(&s->parser, process_event);
863 if (!register_signal_handlers()) {
864 g_critical("failed to register signal handlers");
869 s->main_loop = g_main_loop_new(NULL, false);
870 if (!channel_init(ga_state, method, path)) {
871 g_critical("failed to initialize guest agent channel");
875 g_main_loop_run(ga_state->main_loop);
878 SERVICE_TABLE_ENTRY service_table[] = {
879 { (char *)QGA_SERVICE_NAME, service_main }, { NULL, NULL } };
880 StartServiceCtrlDispatcher(service_table);
882 g_main_loop_run(ga_state->main_loop);
886 ga_command_state_cleanup_all(ga_state->command_state);
887 ga_channel_free(ga_state->channel);
890 unlink(pid_filepath);
896 unlink(pid_filepath);