Merge tag 'pull-la-20220704' of https://gitlab.com/rth7680/qemu into staging
[qemu.git] / qga / commands.c
1 /*
2 * QEMU Guest Agent common/cross-platform command implementations
3 *
4 * Copyright IBM Corp. 2012
5 *
6 * Authors:
7 * Michael Roth <mdroth@linux.vnet.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include "qemu/units.h"
15 #include "guest-agent-core.h"
16 #include "qga-qapi-commands.h"
17 #include "qapi/error.h"
18 #include "qapi/qmp/qerror.h"
19 #include "qemu/base64.h"
20 #include "qemu/cutils.h"
21 #include "commands-common.h"
22
23 /* Maximum captured guest-exec out_data/err_data - 16MB */
24 #define GUEST_EXEC_MAX_OUTPUT (16 * 1024 * 1024)
25 /* Allocation and I/O buffer for reading guest-exec out_data/err_data - 4KB */
26 #define GUEST_EXEC_IO_SIZE (4 * 1024)
27 /*
28 * Maximum file size to read - 48MB
29 *
30 * (48MB + Base64 3:4 overhead = JSON parser 64 MB limit)
31 */
32 #define GUEST_FILE_READ_COUNT_MAX (48 * MiB)
33
34 /* Note: in some situations, like with the fsfreeze, logging may be
35 * temporarilly disabled. if it is necessary that a command be able
36 * to log for accounting purposes, check ga_logging_enabled() beforehand,
37 * and use the QERR_QGA_LOGGING_DISABLED to generate an error
38 */
39 void slog(const gchar *fmt, ...)
40 {
41 va_list ap;
42
43 va_start(ap, fmt);
44 g_logv("syslog", G_LOG_LEVEL_INFO, fmt, ap);
45 va_end(ap);
46 }
47
48 int64_t qmp_guest_sync_delimited(int64_t id, Error **errp)
49 {
50 ga_set_response_delimited(ga_state);
51 return id;
52 }
53
54 int64_t qmp_guest_sync(int64_t id, Error **errp)
55 {
56 return id;
57 }
58
59 void qmp_guest_ping(Error **errp)
60 {
61 slog("guest-ping called");
62 }
63
64 static void qmp_command_info(const QmpCommand *cmd, void *opaque)
65 {
66 GuestAgentInfo *info = opaque;
67 GuestAgentCommandInfo *cmd_info;
68
69 cmd_info = g_new0(GuestAgentCommandInfo, 1);
70 cmd_info->name = g_strdup(qmp_command_name(cmd));
71 cmd_info->enabled = qmp_command_is_enabled(cmd);
72 cmd_info->success_response = qmp_has_success_response(cmd);
73
74 QAPI_LIST_PREPEND(info->supported_commands, cmd_info);
75 }
76
77 struct GuestAgentInfo *qmp_guest_info(Error **errp)
78 {
79 GuestAgentInfo *info = g_new0(GuestAgentInfo, 1);
80
81 info->version = g_strdup(QEMU_VERSION);
82 qmp_for_each_command(&ga_commands, qmp_command_info, info);
83 return info;
84 }
85
86 struct GuestExecIOData {
87 guchar *data;
88 gsize size;
89 gsize length;
90 bool closed;
91 bool truncated;
92 const char *name;
93 };
94 typedef struct GuestExecIOData GuestExecIOData;
95
96 struct GuestExecInfo {
97 GPid pid;
98 int64_t pid_numeric;
99 gint status;
100 bool has_output;
101 bool finished;
102 GuestExecIOData in;
103 GuestExecIOData out;
104 GuestExecIOData err;
105 QTAILQ_ENTRY(GuestExecInfo) next;
106 };
107 typedef struct GuestExecInfo GuestExecInfo;
108
109 static struct {
110 QTAILQ_HEAD(, GuestExecInfo) processes;
111 } guest_exec_state = {
112 .processes = QTAILQ_HEAD_INITIALIZER(guest_exec_state.processes),
113 };
114
115 static int64_t gpid_to_int64(GPid pid)
116 {
117 #ifdef G_OS_WIN32
118 return GetProcessId(pid);
119 #else
120 return (int64_t)pid;
121 #endif
122 }
123
124 static GuestExecInfo *guest_exec_info_add(GPid pid)
125 {
126 GuestExecInfo *gei;
127
128 gei = g_new0(GuestExecInfo, 1);
129 gei->pid = pid;
130 gei->pid_numeric = gpid_to_int64(pid);
131 QTAILQ_INSERT_TAIL(&guest_exec_state.processes, gei, next);
132
133 return gei;
134 }
135
136 static GuestExecInfo *guest_exec_info_find(int64_t pid_numeric)
137 {
138 GuestExecInfo *gei;
139
140 QTAILQ_FOREACH(gei, &guest_exec_state.processes, next) {
141 if (gei->pid_numeric == pid_numeric) {
142 return gei;
143 }
144 }
145
146 return NULL;
147 }
148
149 GuestExecStatus *qmp_guest_exec_status(int64_t pid, Error **errp)
150 {
151 GuestExecInfo *gei;
152 GuestExecStatus *ges;
153
154 slog("guest-exec-status called, pid: %u", (uint32_t)pid);
155
156 gei = guest_exec_info_find(pid);
157 if (gei == NULL) {
158 error_setg(errp, QERR_INVALID_PARAMETER, "pid");
159 return NULL;
160 }
161
162 ges = g_new0(GuestExecStatus, 1);
163
164 bool finished = gei->finished;
165
166 /* need to wait till output channels are closed
167 * to be sure we captured all output at this point */
168 if (gei->has_output) {
169 finished &= gei->out.closed && gei->err.closed;
170 }
171
172 ges->exited = finished;
173 if (finished) {
174 /* Glib has no portable way to parse exit status.
175 * On UNIX, we can get either exit code from normal termination
176 * or signal number.
177 * On Windows, it is either the same exit code or the exception
178 * value for an unhandled exception that caused the process
179 * to terminate.
180 * See MSDN for GetExitCodeProcess() and ntstatus.h for possible
181 * well-known codes, e.g. C0000005 ACCESS_DENIED - analog of SIGSEGV
182 * References:
183 * https://msdn.microsoft.com/en-us/library/windows/desktop/ms683189(v=vs.85).aspx
184 * https://msdn.microsoft.com/en-us/library/aa260331(v=vs.60).aspx
185 */
186 #ifdef G_OS_WIN32
187 /* Additionally WIN32 does not provide any additional information
188 * on whether the child exited or terminated via signal.
189 * We use this simple range check to distinguish application exit code
190 * (usually value less then 256) and unhandled exception code with
191 * ntstatus (always value greater then 0xC0000005). */
192 if ((uint32_t)gei->status < 0xC0000000U) {
193 ges->has_exitcode = true;
194 ges->exitcode = gei->status;
195 } else {
196 ges->has_signal = true;
197 ges->signal = gei->status;
198 }
199 #else
200 if (WIFEXITED(gei->status)) {
201 ges->has_exitcode = true;
202 ges->exitcode = WEXITSTATUS(gei->status);
203 } else if (WIFSIGNALED(gei->status)) {
204 ges->has_signal = true;
205 ges->signal = WTERMSIG(gei->status);
206 }
207 #endif
208 if (gei->out.length > 0) {
209 ges->has_out_data = true;
210 ges->out_data = g_base64_encode(gei->out.data, gei->out.length);
211 g_free(gei->out.data);
212 ges->has_out_truncated = gei->out.truncated;
213 }
214
215 if (gei->err.length > 0) {
216 ges->has_err_data = true;
217 ges->err_data = g_base64_encode(gei->err.data, gei->err.length);
218 g_free(gei->err.data);
219 ges->has_err_truncated = gei->err.truncated;
220 }
221
222 QTAILQ_REMOVE(&guest_exec_state.processes, gei, next);
223 g_free(gei);
224 }
225
226 return ges;
227 }
228
229 /* Get environment variables or arguments array for execve(). */
230 static char **guest_exec_get_args(const strList *entry, bool log)
231 {
232 const strList *it;
233 int count = 1, i = 0; /* reserve for NULL terminator */
234 char **args;
235 char *str; /* for logging array of arguments */
236 size_t str_size = 1;
237
238 for (it = entry; it != NULL; it = it->next) {
239 count++;
240 str_size += 1 + strlen(it->value);
241 }
242
243 str = g_malloc(str_size);
244 *str = 0;
245 args = g_new(char *, count);
246 for (it = entry; it != NULL; it = it->next) {
247 args[i++] = it->value;
248 pstrcat(str, str_size, it->value);
249 if (it->next) {
250 pstrcat(str, str_size, " ");
251 }
252 }
253 args[i] = NULL;
254
255 if (log) {
256 slog("guest-exec called: \"%s\"", str);
257 }
258 g_free(str);
259
260 return args;
261 }
262
263 static void guest_exec_child_watch(GPid pid, gint status, gpointer data)
264 {
265 GuestExecInfo *gei = (GuestExecInfo *)data;
266
267 g_debug("guest_exec_child_watch called, pid: %d, status: %u",
268 (int32_t)gpid_to_int64(pid), (uint32_t)status);
269
270 gei->status = status;
271 gei->finished = true;
272
273 g_spawn_close_pid(pid);
274 }
275
276 /** Reset ignored signals back to default. */
277 static void guest_exec_task_setup(gpointer data)
278 {
279 #if !defined(G_OS_WIN32)
280 struct sigaction sigact;
281
282 memset(&sigact, 0, sizeof(struct sigaction));
283 sigact.sa_handler = SIG_DFL;
284
285 if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
286 slog("sigaction() failed to reset child process's SIGPIPE: %s",
287 strerror(errno));
288 }
289 #endif
290 }
291
292 static gboolean guest_exec_input_watch(GIOChannel *ch,
293 GIOCondition cond, gpointer p_)
294 {
295 GuestExecIOData *p = (GuestExecIOData *)p_;
296 gsize bytes_written = 0;
297 GIOStatus status;
298 GError *gerr = NULL;
299
300 /* nothing left to write */
301 if (p->size == p->length) {
302 goto done;
303 }
304
305 status = g_io_channel_write_chars(ch, (gchar *)p->data + p->length,
306 p->size - p->length, &bytes_written, &gerr);
307
308 /* can be not 0 even if not G_IO_STATUS_NORMAL */
309 if (bytes_written != 0) {
310 p->length += bytes_written;
311 }
312
313 /* continue write, our callback will be called again */
314 if (status == G_IO_STATUS_NORMAL || status == G_IO_STATUS_AGAIN) {
315 return true;
316 }
317
318 if (gerr) {
319 g_warning("qga: i/o error writing to input_data channel: %s",
320 gerr->message);
321 g_error_free(gerr);
322 }
323
324 done:
325 g_io_channel_shutdown(ch, true, NULL);
326 g_io_channel_unref(ch);
327 p->closed = true;
328 g_free(p->data);
329
330 return false;
331 }
332
333 static gboolean guest_exec_output_watch(GIOChannel *ch,
334 GIOCondition cond, gpointer p_)
335 {
336 GuestExecIOData *p = (GuestExecIOData *)p_;
337 gsize bytes_read;
338 GIOStatus gstatus;
339
340 if (cond == G_IO_HUP || cond == G_IO_ERR) {
341 goto close;
342 }
343
344 if (p->size == p->length) {
345 gpointer t = NULL;
346 if (!p->truncated && p->size < GUEST_EXEC_MAX_OUTPUT) {
347 t = g_try_realloc(p->data, p->size + GUEST_EXEC_IO_SIZE);
348 }
349 if (t == NULL) {
350 /* ignore truncated output */
351 gchar buf[GUEST_EXEC_IO_SIZE];
352
353 p->truncated = true;
354 gstatus = g_io_channel_read_chars(ch, buf, sizeof(buf),
355 &bytes_read, NULL);
356 if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) {
357 goto close;
358 }
359
360 return true;
361 }
362 p->size += GUEST_EXEC_IO_SIZE;
363 p->data = t;
364 }
365
366 /* Calling read API once.
367 * On next available data our callback will be called again */
368 gstatus = g_io_channel_read_chars(ch, (gchar *)p->data + p->length,
369 p->size - p->length, &bytes_read, NULL);
370 if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) {
371 goto close;
372 }
373
374 p->length += bytes_read;
375
376 return true;
377
378 close:
379 g_io_channel_shutdown(ch, true, NULL);
380 g_io_channel_unref(ch);
381 p->closed = true;
382 return false;
383 }
384
385 GuestExec *qmp_guest_exec(const char *path,
386 bool has_arg, strList *arg,
387 bool has_env, strList *env,
388 bool has_input_data, const char *input_data,
389 bool has_capture_output, bool capture_output,
390 Error **errp)
391 {
392 GPid pid;
393 GuestExec *ge = NULL;
394 GuestExecInfo *gei;
395 char **argv, **envp;
396 strList arglist;
397 gboolean ret;
398 GError *gerr = NULL;
399 gint in_fd, out_fd, err_fd;
400 GIOChannel *in_ch, *out_ch, *err_ch;
401 GSpawnFlags flags;
402 bool has_output = (has_capture_output && capture_output);
403 g_autofree uint8_t *input = NULL;
404 size_t ninput = 0;
405
406 arglist.value = (char *)path;
407 arglist.next = has_arg ? arg : NULL;
408
409 if (has_input_data) {
410 input = qbase64_decode(input_data, -1, &ninput, errp);
411 if (!input) {
412 return NULL;
413 }
414 }
415
416 argv = guest_exec_get_args(&arglist, true);
417 envp = has_env ? guest_exec_get_args(env, false) : NULL;
418
419 flags = G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD |
420 G_SPAWN_SEARCH_PATH_FROM_ENVP;
421 if (!has_output) {
422 flags |= G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL;
423 }
424
425 ret = g_spawn_async_with_pipes(NULL, argv, envp, flags,
426 guest_exec_task_setup, NULL, &pid, has_input_data ? &in_fd : NULL,
427 has_output ? &out_fd : NULL, has_output ? &err_fd : NULL, &gerr);
428 if (!ret) {
429 error_setg(errp, QERR_QGA_COMMAND_FAILED, gerr->message);
430 g_error_free(gerr);
431 goto done;
432 }
433
434 ge = g_new0(GuestExec, 1);
435 ge->pid = gpid_to_int64(pid);
436
437 gei = guest_exec_info_add(pid);
438 gei->has_output = has_output;
439 g_child_watch_add(pid, guest_exec_child_watch, gei);
440
441 if (has_input_data) {
442 gei->in.data = g_steal_pointer(&input);
443 gei->in.size = ninput;
444 #ifdef G_OS_WIN32
445 in_ch = g_io_channel_win32_new_fd(in_fd);
446 #else
447 in_ch = g_io_channel_unix_new(in_fd);
448 #endif
449 g_io_channel_set_encoding(in_ch, NULL, NULL);
450 g_io_channel_set_buffered(in_ch, false);
451 g_io_channel_set_flags(in_ch, G_IO_FLAG_NONBLOCK, NULL);
452 g_io_channel_set_close_on_unref(in_ch, true);
453 g_io_add_watch(in_ch, G_IO_OUT, guest_exec_input_watch, &gei->in);
454 }
455
456 if (has_output) {
457 #ifdef G_OS_WIN32
458 out_ch = g_io_channel_win32_new_fd(out_fd);
459 err_ch = g_io_channel_win32_new_fd(err_fd);
460 #else
461 out_ch = g_io_channel_unix_new(out_fd);
462 err_ch = g_io_channel_unix_new(err_fd);
463 #endif
464 g_io_channel_set_encoding(out_ch, NULL, NULL);
465 g_io_channel_set_encoding(err_ch, NULL, NULL);
466 g_io_channel_set_buffered(out_ch, false);
467 g_io_channel_set_buffered(err_ch, false);
468 g_io_channel_set_close_on_unref(out_ch, true);
469 g_io_channel_set_close_on_unref(err_ch, true);
470 g_io_add_watch(out_ch, G_IO_IN | G_IO_HUP,
471 guest_exec_output_watch, &gei->out);
472 g_io_add_watch(err_ch, G_IO_IN | G_IO_HUP,
473 guest_exec_output_watch, &gei->err);
474 }
475
476 done:
477 g_free(argv);
478 g_free(envp);
479
480 return ge;
481 }
482
483 /* Convert GuestFileWhence (either a raw integer or an enum value) into
484 * the guest's SEEK_ constants. */
485 int ga_parse_whence(GuestFileWhence *whence, Error **errp)
486 {
487 /*
488 * Exploit the fact that we picked values to match QGA_SEEK_*;
489 * however, we have to use a temporary variable since the union
490 * members may have different size.
491 */
492 if (whence->type == QTYPE_QSTRING) {
493 int value = whence->u.name;
494 whence->type = QTYPE_QNUM;
495 whence->u.value = value;
496 }
497 switch (whence->u.value) {
498 case QGA_SEEK_SET:
499 return SEEK_SET;
500 case QGA_SEEK_CUR:
501 return SEEK_CUR;
502 case QGA_SEEK_END:
503 return SEEK_END;
504 }
505 error_setg(errp, "invalid whence code %"PRId64, whence->u.value);
506 return -1;
507 }
508
509 GuestHostName *qmp_guest_get_host_name(Error **errp)
510 {
511 GuestHostName *result = NULL;
512 g_autofree char *hostname = qga_get_host_name(errp);
513
514 /*
515 * We want to avoid using g_get_host_name() because that
516 * caches the result and we wouldn't reflect changes in the
517 * host name.
518 */
519
520 if (!hostname) {
521 hostname = g_strdup("localhost");
522 }
523
524 result = g_new0(GuestHostName, 1);
525 result->host_name = g_steal_pointer(&hostname);
526 return result;
527 }
528
529 GuestTimezone *qmp_guest_get_timezone(Error **errp)
530 {
531 GuestTimezone *info = NULL;
532 GTimeZone *tz = NULL;
533 gint64 now = 0;
534 gint32 intv = 0;
535 gchar const *name = NULL;
536
537 info = g_new0(GuestTimezone, 1);
538 tz = g_time_zone_new_local();
539 if (tz == NULL) {
540 error_setg(errp, QERR_QGA_COMMAND_FAILED,
541 "Couldn't retrieve local timezone");
542 goto error;
543 }
544
545 now = g_get_real_time() / G_USEC_PER_SEC;
546 intv = g_time_zone_find_interval(tz, G_TIME_TYPE_UNIVERSAL, now);
547 info->offset = g_time_zone_get_offset(tz, intv);
548 name = g_time_zone_get_abbreviation(tz, intv);
549 if (name != NULL) {
550 info->has_zone = true;
551 info->zone = g_strdup(name);
552 }
553 g_time_zone_unref(tz);
554
555 return info;
556
557 error:
558 g_free(info);
559 return NULL;
560 }
561
562 GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count,
563 int64_t count, Error **errp)
564 {
565 GuestFileHandle *gfh = guest_file_handle_find(handle, errp);
566 GuestFileRead *read_data;
567
568 if (!gfh) {
569 return NULL;
570 }
571 if (!has_count) {
572 count = QGA_READ_COUNT_DEFAULT;
573 } else if (count < 0 || count > GUEST_FILE_READ_COUNT_MAX) {
574 error_setg(errp, "value '%" PRId64 "' is invalid for argument count",
575 count);
576 return NULL;
577 }
578
579 read_data = guest_file_read_unsafe(gfh, count, errp);
580 if (!read_data) {
581 slog("guest-file-write failed, handle: %" PRId64, handle);
582 }
583
584 return read_data;
585 }
586
587 int64_t qmp_guest_get_time(Error **errp)
588 {
589 return g_get_real_time() * 1000;
590 }